fs/ext4/super.c

   1 /*
   2  *  linux/fs/ext4/super.c
   3  *
   4  * Copyright (C) 1992, 1993, 1994, 1995
   5  * Remy Card (card@masi.ibp.fr)
   6  * Laboratoire MASI - Institut Blaise Pascal
   7  * Universite Pierre et Marie Curie (Paris VI)
   8  *
   9  *  from
  10  *
  11  *  linux/fs/minix/inode.c
  12  *
  13  *  Copyright (C) 1991, 1992  Linus Torvalds
  14  *
  15  *  Big-endian to little-endian byte-swapping/bitmaps by
  16  *        David S. Miller (davem@caip.rutgers.edu), 1995
  17  */
  18
  19 #include <linux/module.h>
  20 #include <linux/string.h>
  21 #include <linux/fs.h>
  22 #include <linux/time.h>
  23 #include <linux/vmalloc.h>
  24 #include <linux/slab.h>
  25 #include <linux/init.h>
  26 #include <linux/blkdev.h>
  27 #include <linux/backing-dev.h>
  28 #include <linux/parser.h>
  29 #include <linux/buffer_head.h>
  30 #include <linux/exportfs.h>
  31 #include <linux/vfs.h>
  32 #include <linux/random.h>
  33 #include <linux/mount.h>
  34 #include <linux/namei.h>
  35 #include <linux/quotaops.h>
  36 #include <linux/seq_file.h>
  37 #include <linux/ctype.h>
  38 #include <linux/log2.h>
  39 #include <linux/crc16.h>
  40 #include <linux/cleancache.h>
  41 #include <asm/uaccess.h>
  42
  43 #include <linux/kthread.h>
  44 #include <linux/freezer.h>
  45
  46 #include "ext4.h"
  47 #include "ext4_extents.h"       /* Needed for trace points definition */
  48 #include "ext4_jbd2.h"
  49 #include "xattr.h"
  50 #include "acl.h"
  51 #include "mballoc.h"
  52
  53 #define CREATE_TRACE_POINTS
  54 #include <trace/events/ext4.h>
  55
  56 static struct ext4_lazy_init *ext4_li_info;
  57 static struct mutex ext4_li_mtx;
  58 static struct ratelimit_state ext4_mount_msg_ratelimit;
  59
  60 static int ext4_load_journal(struct super_block *, struct ext4_super_block *,
  61                              unsigned long journal_devnum);
  62 static int ext4_show_options(struct seq_file *seq, struct dentry *root);
  63 static int ext4_commit_super(struct super_block *sb, int sync);
  64 static void ext4_mark_recovery_complete(struct super_block *sb,
  65                                         struct ext4_super_block *es);
  66 static void ext4_clear_journal_err(struct super_block *sb,
  67                                    struct ext4_super_block *es);
  68 static int ext4_sync_fs(struct super_block *sb, int wait);
  69 static int ext4_remount(struct super_block *sb, int *flags, char *data);
  70 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf);
  71 static int ext4_unfreeze(struct super_block *sb);
  72 static int ext4_freeze(struct super_block *sb);
  73 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
  74                        const char *dev_name, void *data);
  75 static inline int ext2_feature_set_ok(struct super_block *sb);
  76 static inline int ext3_feature_set_ok(struct super_block *sb);
  77 static int ext4_feature_set_ok(struct super_block *sb, int readonly);
  78 static void ext4_destroy_lazyinit_thread(void);
  79 static void ext4_unregister_li_request(struct super_block *sb);
  80 static void ext4_clear_request_list(void);
  81 static struct inode *ext4_get_journal_inode(struct super_block *sb,
  82                                             unsigned int journal_inum);
  83
  84 /*
  85  * Lock ordering
  86  *
  87  * Note the difference between i_mmap_sem (EXT4_I(inode)->i_mmap_sem) and
  88  * i_mmap_rwsem (inode->i_mmap_rwsem)!
  89  *
  90  * page fault path:
  91  * mmap_sem -> sb_start_pagefault -> i_mmap_sem (r) -> transaction start ->
  92  *   page lock -> i_data_sem (rw)
  93  *
  94  * buffered write path:
  95  * sb_start_write -> i_mutex -> mmap_sem
  96  * sb_start_write -> i_mutex -> transaction start -> page lock ->
  97  *   i_data_sem (rw)
  98  *
  99  * truncate:
 100  * sb_start_write -> i_mutex -> EXT4_STATE_DIOREAD_LOCK (w) -> i_mmap_sem (w) ->
 101  *   i_mmap_rwsem (w) -> page lock
 102  * sb_start_write -> i_mutex -> EXT4_STATE_DIOREAD_LOCK (w) -> i_mmap_sem (w) ->
 103  *   transaction start -> i_data_sem (rw)
 104  *
 105  * direct IO:
 106  * sb_start_write -> i_mutex -> EXT4_STATE_DIOREAD_LOCK (r) -> mmap_sem
 107  * sb_start_write -> i_mutex -> EXT4_STATE_DIOREAD_LOCK (r) ->
 108  *   transaction start -> i_data_sem (rw)
 109  *
 110  * writepages:
 111  * transaction start -> page lock(s) -> i_data_sem (rw)
 112  */
 113
 114 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
 115 static struct file_system_type ext2_fs_type = {
 116         .owner          = THIS_MODULE,
 117         .name           = "ext2",
 118         .mount          = ext4_mount,
 119         .kill_sb        = kill_block_super,
 120         .fs_flags       = FS_REQUIRES_DEV,
 121 };
 122 MODULE_ALIAS_FS("ext2");
 123 MODULE_ALIAS("ext2");
 124 #define IS_EXT2_SB(sb) ((sb)->s_bdev->bd_holder == &ext2_fs_type)
 125 #else
 126 #define IS_EXT2_SB(sb) (0)
 127 #endif
 128
 129
 130 static struct file_system_type ext3_fs_type = {
 131         .owner          = THIS_MODULE,
 132         .name           = "ext3",
 133         .mount          = ext4_mount,
 134         .kill_sb        = kill_block_super,
 135         .fs_flags       = FS_REQUIRES_DEV,
 136 };
 137 MODULE_ALIAS_FS("ext3");
 138 MODULE_ALIAS("ext3");
 139 #define IS_EXT3_SB(sb) ((sb)->s_bdev->bd_holder == &ext3_fs_type)
 140
 141 static int ext4_verify_csum_type(struct super_block *sb,
 142                                  struct ext4_super_block *es)
 143 {
 144         if (!ext4_has_feature_metadata_csum(sb))
 145                 return 1;
 146
 147         return es->s_checksum_type == EXT4_CRC32C_CHKSUM;
 148 }
 149
 150 static __le32 ext4_superblock_csum(struct super_block *sb,
 151                                    struct ext4_super_block *es)
 152 {
 153         struct ext4_sb_info *sbi = EXT4_SB(sb);
 154         int offset = offsetof(struct ext4_super_block, s_checksum);
 155         __u32 csum;
 156
 157         csum = ext4_chksum(sbi, ~0, (char *)es, offset);
 158
 159         return cpu_to_le32(csum);
 160 }
 161
 162 static int ext4_superblock_csum_verify(struct super_block *sb,
 163                                        struct ext4_super_block *es)
 164 {
 165         if (!ext4_has_metadata_csum(sb))
 166                 return 1;
 167
 168         return es->s_checksum == ext4_superblock_csum(sb, es);
 169 }
 170
 171 void ext4_superblock_csum_set(struct super_block *sb)
 172 {
 173         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 174
 175         if (!ext4_has_metadata_csum(sb))
 176                 return;
 177
 178         es->s_checksum = ext4_superblock_csum(sb, es);
 179 }
 180
 181 void *ext4_kvmalloc(size_t size, gfp_t flags)
 182 {
 183         void *ret;
 184
 185         ret = kmalloc(size, flags | __GFP_NOWARN);
 186         if (!ret)
 187                 ret = __vmalloc(size, flags, PAGE_KERNEL);
 188         return ret;
 189 }
 190
 191 void *ext4_kvzalloc(size_t size, gfp_t flags)
 192 {
 193         void *ret;
 194
 195         ret = kzalloc(size, flags | __GFP_NOWARN);
 196         if (!ret)
 197                 ret = __vmalloc(size, flags | __GFP_ZERO, PAGE_KERNEL);
 198         return ret;
 199 }
 200
 201 ext4_fsblk_t ext4_block_bitmap(struct super_block *sb,
 202                                struct ext4_group_desc *bg)
 203 {
 204         return le32_to_cpu(bg->bg_block_bitmap_lo) |
 205                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 206                  (ext4_fsblk_t)le32_to_cpu(bg->bg_block_bitmap_hi) << 32 : 0);
 207 }
 208
 209 ext4_fsblk_t ext4_inode_bitmap(struct super_block *sb,
 210                                struct ext4_group_desc *bg)
 211 {
 212         return le32_to_cpu(bg->bg_inode_bitmap_lo) |
 213                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 214                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_bitmap_hi) << 32 : 0);
 215 }
 216
 217 ext4_fsblk_t ext4_inode_table(struct super_block *sb,
 218                               struct ext4_group_desc *bg)
 219 {
 220         return le32_to_cpu(bg->bg_inode_table_lo) |
 221                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 222                  (ext4_fsblk_t)le32_to_cpu(bg->bg_inode_table_hi) << 32 : 0);
 223 }
 224
 225 __u32 ext4_free_group_clusters(struct super_block *sb,
 226                                struct ext4_group_desc *bg)
 227 {
 228         return le16_to_cpu(bg->bg_free_blocks_count_lo) |
 229                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 230                  (__u32)le16_to_cpu(bg->bg_free_blocks_count_hi) << 16 : 0);
 231 }
 232
 233 __u32 ext4_free_inodes_count(struct super_block *sb,
 234                               struct ext4_group_desc *bg)
 235 {
 236         return le16_to_cpu(bg->bg_free_inodes_count_lo) |
 237                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 238                  (__u32)le16_to_cpu(bg->bg_free_inodes_count_hi) << 16 : 0);
 239 }
 240
 241 __u32 ext4_used_dirs_count(struct super_block *sb,
 242                               struct ext4_group_desc *bg)
 243 {
 244         return le16_to_cpu(bg->bg_used_dirs_count_lo) |
 245                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 246                  (__u32)le16_to_cpu(bg->bg_used_dirs_count_hi) << 16 : 0);
 247 }
 248
 249 __u32 ext4_itable_unused_count(struct super_block *sb,
 250                               struct ext4_group_desc *bg)
 251 {
 252         return le16_to_cpu(bg->bg_itable_unused_lo) |
 253                 (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT ?
 254                  (__u32)le16_to_cpu(bg->bg_itable_unused_hi) << 16 : 0);
 255 }
 256
 257 void ext4_block_bitmap_set(struct super_block *sb,
 258                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 259 {
 260         bg->bg_block_bitmap_lo = cpu_to_le32((u32)blk);
 261         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 262                 bg->bg_block_bitmap_hi = cpu_to_le32(blk >> 32);
 263 }
 264
 265 void ext4_inode_bitmap_set(struct super_block *sb,
 266                            struct ext4_group_desc *bg, ext4_fsblk_t blk)
 267 {
 268         bg->bg_inode_bitmap_lo  = cpu_to_le32((u32)blk);
 269         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 270                 bg->bg_inode_bitmap_hi = cpu_to_le32(blk >> 32);
 271 }
 272
 273 void ext4_inode_table_set(struct super_block *sb,
 274                           struct ext4_group_desc *bg, ext4_fsblk_t blk)
 275 {
 276         bg->bg_inode_table_lo = cpu_to_le32((u32)blk);
 277         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 278                 bg->bg_inode_table_hi = cpu_to_le32(blk >> 32);
 279 }
 280
 281 void ext4_free_group_clusters_set(struct super_block *sb,
 282                                   struct ext4_group_desc *bg, __u32 count)
 283 {
 284         bg->bg_free_blocks_count_lo = cpu_to_le16((__u16)count);
 285         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 286                 bg->bg_free_blocks_count_hi = cpu_to_le16(count >> 16);
 287 }
 288
 289 void ext4_free_inodes_set(struct super_block *sb,
 290                           struct ext4_group_desc *bg, __u32 count)
 291 {
 292         bg->bg_free_inodes_count_lo = cpu_to_le16((__u16)count);
 293         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 294                 bg->bg_free_inodes_count_hi = cpu_to_le16(count >> 16);
 295 }
 296
 297 void ext4_used_dirs_set(struct super_block *sb,
 298                           struct ext4_group_desc *bg, __u32 count)
 299 {
 300         bg->bg_used_dirs_count_lo = cpu_to_le16((__u16)count);
 301         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 302                 bg->bg_used_dirs_count_hi = cpu_to_le16(count >> 16);
 303 }
 304
 305 void ext4_itable_unused_set(struct super_block *sb,
 306                           struct ext4_group_desc *bg, __u32 count)
 307 {
 308         bg->bg_itable_unused_lo = cpu_to_le16((__u16)count);
 309         if (EXT4_DESC_SIZE(sb) >= EXT4_MIN_DESC_SIZE_64BIT)
 310                 bg->bg_itable_unused_hi = cpu_to_le16(count >> 16);
 311 }
 312
 313
 314 static void __save_error_info(struct super_block *sb, const char *func,
 315                             unsigned int line)
 316 {
 317         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 318
 319         EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
 320         if (bdev_read_only(sb->s_bdev))
 321                 return;
 322         es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
 323         es->s_last_error_time = cpu_to_le32(get_seconds());
 324         strncpy(es->s_last_error_func, func, sizeof(es->s_last_error_func));
 325         es->s_last_error_line = cpu_to_le32(line);
 326         if (!es->s_first_error_time) {
 327                 es->s_first_error_time = es->s_last_error_time;
 328                 strncpy(es->s_first_error_func, func,
 329                         sizeof(es->s_first_error_func));
 330                 es->s_first_error_line = cpu_to_le32(line);
 331                 es->s_first_error_ino = es->s_last_error_ino;
 332                 es->s_first_error_block = es->s_last_error_block;
 333         }
 334         /*
 335          * Start the daily error reporting function if it hasn't been
 336          * started already
 337          */
 338         if (!es->s_error_count)
 339                 mod_timer(&EXT4_SB(sb)->s_err_report, jiffies + 24*60*60*HZ);
 340         le32_add_cpu(&es->s_error_count, 1);
 341 }
 342
 343 static void save_error_info(struct super_block *sb, const char *func,
 344                             unsigned int line)
 345 {
 346         __save_error_info(sb, func, line);
 347         if (!bdev_read_only(sb->s_bdev))
 348                 ext4_commit_super(sb, 1);
 349 }
 350
 351 /*
 352  * The del_gendisk() function uninitializes the disk-specific data
 353  * structures, including the bdi structure, without telling anyone
 354  * else.  Once this happens, any attempt to call mark_buffer_dirty()
 355  * (for example, by ext4_commit_super), will cause a kernel OOPS.
 356  * This is a kludge to prevent these oops until we can put in a proper
 357  * hook in del_gendisk() to inform the VFS and file system layers.
 358  */
 359 static int block_device_ejected(struct super_block *sb)
 360 {
 361         struct inode *bd_inode = sb->s_bdev->bd_inode;
 362         struct backing_dev_info *bdi = inode_to_bdi(bd_inode);
 363
 364         return bdi->dev == NULL;
 365 }
 366
 367 static void ext4_journal_commit_callback(journal_t *journal, transaction_t *txn)
 368 {
 369         struct super_block              *sb = journal->j_private;
 370         struct ext4_sb_info             *sbi = EXT4_SB(sb);
 371         int                             error = is_journal_aborted(journal);
 372         struct ext4_journal_cb_entry    *jce;
 373
 374         BUG_ON(txn->t_state == T_FINISHED);
 375         spin_lock(&sbi->s_md_lock);
 376         while (!list_empty(&txn->t_private_list)) {
 377                 jce = list_entry(txn->t_private_list.next,
 378                                  struct ext4_journal_cb_entry, jce_list);
 379                 list_del_init(&jce->jce_list);
 380                 spin_unlock(&sbi->s_md_lock);
 381                 jce->jce_func(sb, jce, error);
 382                 spin_lock(&sbi->s_md_lock);
 383         }
 384         spin_unlock(&sbi->s_md_lock);
 385 }
 386
 387 /* Deal with the reporting of failure conditions on a filesystem such as
 388  * inconsistencies detected or read IO failures.
 389  *
 390  * On ext2, we can store the error state of the filesystem in the
 391  * superblock.  That is not possible on ext4, because we may have other
 392  * write ordering constraints on the superblock which prevent us from
 393  * writing it out straight away; and given that the journal is about to
 394  * be aborted, we can't rely on the current, or future, transactions to
 395  * write out the superblock safely.
 396  *
 397  * We'll just use the jbd2_journal_abort() error code to record an error in
 398  * the journal instead.  On recovery, the journal will complain about
 399  * that error until we've noted it down and cleared it.
 400  */
 401
 402 static void ext4_handle_error(struct super_block *sb)
 403 {
 404         if (sb->s_flags & MS_RDONLY)
 405                 return;
 406
 407         if (!test_opt(sb, ERRORS_CONT)) {
 408                 journal_t *journal = EXT4_SB(sb)->s_journal;
 409
 410                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 411                 if (journal)
 412                         jbd2_journal_abort(journal, -EIO);
 413         }
 414         if (test_opt(sb, ERRORS_RO)) {
 415                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 416                 /*
 417                  * Make sure updated value of ->s_mount_flags will be visible
 418                  * before ->s_flags update
 419                  */
 420                 smp_wmb();
 421                 sb->s_flags |= MS_RDONLY;
 422         }
 423         if (test_opt(sb, ERRORS_PANIC)) {
 424                 if (EXT4_SB(sb)->s_journal &&
 425                   !(EXT4_SB(sb)->s_journal->j_flags & JBD2_REC_ERR))
 426                         return;
 427                 panic("EXT4-fs (device %s): panic forced after error\n",
 428                         sb->s_id);
 429         }
 430 }
 431
 432 #define ext4_error_ratelimit(sb)                                        \
 433                 ___ratelimit(&(EXT4_SB(sb)->s_err_ratelimit_state),     \
 434                              "EXT4-fs error")
 435
 436 void __ext4_error(struct super_block *sb, const char *function,
 437                   unsigned int line, const char *fmt, ...)
 438 {
 439         struct va_format vaf;
 440         va_list args;
 441
 442         if (ext4_error_ratelimit(sb)) {
 443                 va_start(args, fmt);
 444                 vaf.fmt = fmt;
 445                 vaf.va = &args;
 446                 printk(KERN_CRIT
 447                        "EXT4-fs error (device %s): %s:%d: comm %s: %pV\n",
 448                        sb->s_id, function, line, current->comm, &vaf);
 449                 va_end(args);
 450         }
 451         save_error_info(sb, function, line);
 452         ext4_handle_error(sb);
 453 }
 454
 455 void __ext4_error_inode(struct inode *inode, const char *function,
 456                         unsigned int line, ext4_fsblk_t block,
 457                         const char *fmt, ...)
 458 {
 459         va_list args;
 460         struct va_format vaf;
 461         struct ext4_super_block *es = EXT4_SB(inode->i_sb)->s_es;
 462
 463         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 464         es->s_last_error_block = cpu_to_le64(block);
 465         if (ext4_error_ratelimit(inode->i_sb)) {
 466                 va_start(args, fmt);
 467                 vaf.fmt = fmt;
 468                 vaf.va = &args;
 469                 if (block)
 470                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 471                                "inode #%lu: block %llu: comm %s: %pV\n",
 472                                inode->i_sb->s_id, function, line, inode->i_ino,
 473                                block, current->comm, &vaf);
 474                 else
 475                         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: "
 476                                "inode #%lu: comm %s: %pV\n",
 477                                inode->i_sb->s_id, function, line, inode->i_ino,
 478                                current->comm, &vaf);
 479                 va_end(args);
 480         }
 481         save_error_info(inode->i_sb, function, line);
 482         ext4_handle_error(inode->i_sb);
 483 }
 484
 485 void __ext4_error_file(struct file *file, const char *function,
 486                        unsigned int line, ext4_fsblk_t block,
 487                        const char *fmt, ...)
 488 {
 489         va_list args;
 490         struct va_format vaf;
 491         struct ext4_super_block *es;
 492         struct inode *inode = file_inode(file);
 493         char pathname[80], *path;
 494
 495         es = EXT4_SB(inode->i_sb)->s_es;
 496         es->s_last_error_ino = cpu_to_le32(inode->i_ino);
 497         if (ext4_error_ratelimit(inode->i_sb)) {
 498                 path = file_path(file, pathname, sizeof(pathname));
 499                 if (IS_ERR(path))
 500                         path = "(unknown)";
 501                 va_start(args, fmt);
 502                 vaf.fmt = fmt;
 503                 vaf.va = &args;
 504                 if (block)
 505                         printk(KERN_CRIT
 506                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 507                                "block %llu: comm %s: path %s: %pV\n",
 508                                inode->i_sb->s_id, function, line, inode->i_ino,
 509                                block, current->comm, path, &vaf);
 510                 else
 511                         printk(KERN_CRIT
 512                                "EXT4-fs error (device %s): %s:%d: inode #%lu: "
 513                                "comm %s: path %s: %pV\n",
 514                                inode->i_sb->s_id, function, line, inode->i_ino,
 515                                current->comm, path, &vaf);
 516                 va_end(args);
 517         }
 518         save_error_info(inode->i_sb, function, line);
 519         ext4_handle_error(inode->i_sb);
 520 }
 521
 522 const char *ext4_decode_error(struct super_block *sb, int errno,
 523                               char nbuf[16])
 524 {
 525         char *errstr = NULL;
 526
 527         switch (errno) {
 528         case -EFSCORRUPTED:
 529                 errstr = "Corrupt filesystem";
 530                 break;
 531         case -EFSBADCRC:
 532                 errstr = "Filesystem failed CRC";
 533                 break;
 534         case -EIO:
 535                 errstr = "IO failure";
 536                 break;
 537         case -ENOMEM:
 538                 errstr = "Out of memory";
 539                 break;
 540         case -EROFS:
 541                 if (!sb || (EXT4_SB(sb)->s_journal &&
 542                             EXT4_SB(sb)->s_journal->j_flags & JBD2_ABORT))
 543                         errstr = "Journal has aborted";
 544                 else
 545                         errstr = "Readonly filesystem";
 546                 break;
 547         default:
 548                 /* If the caller passed in an extra buffer for unknown
 549                  * errors, textualise them now.  Else we just return
 550                  * NULL. */
 551                 if (nbuf) {
 552                         /* Check for truncated error codes... */
 553                         if (snprintf(nbuf, 16, "error %d", -errno) >= 0)
 554                                 errstr = nbuf;
 555                 }
 556                 break;
 557         }
 558
 559         return errstr;
 560 }
 561
 562 /* __ext4_std_error decodes expected errors from journaling functions
 563  * automatically and invokes the appropriate error response.  */
 564
 565 void __ext4_std_error(struct super_block *sb, const char *function,
 566                       unsigned int line, int errno)
 567 {
 568         char nbuf[16];
 569         const char *errstr;
 570
 571         /* Special case: if the error is EROFS, and we're not already
 572          * inside a transaction, then there's really no point in logging
 573          * an error. */
 574         if (errno == -EROFS && journal_current_handle() == NULL &&
 575             (sb->s_flags & MS_RDONLY))
 576                 return;
 577
 578         if (ext4_error_ratelimit(sb)) {
 579                 errstr = ext4_decode_error(sb, errno, nbuf);
 580                 printk(KERN_CRIT "EXT4-fs error (device %s) in %s:%d: %s\n",
 581                        sb->s_id, function, line, errstr);
 582         }
 583
 584         save_error_info(sb, function, line);
 585         ext4_handle_error(sb);
 586 }
 587
 588 /*
 589  * ext4_abort is a much stronger failure handler than ext4_error.  The
 590  * abort function may be used to deal with unrecoverable failures such
 591  * as journal IO errors or ENOMEM at a critical moment in log management.
 592  *
 593  * We unconditionally force the filesystem into an ABORT|READONLY state,
 594  * unless the error response on the fs has been set to panic in which
 595  * case we take the easy way out and panic immediately.
 596  */
 597
 598 void __ext4_abort(struct super_block *sb, const char *function,
 599                 unsigned int line, const char *fmt, ...)
 600 {
 601         struct va_format vaf;
 602         va_list args;
 603
 604         save_error_info(sb, function, line);
 605         va_start(args, fmt);
 606         vaf.fmt = fmt;
 607         vaf.va = &args;
 608         printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: %pV\n",
 609                sb->s_id, function, line, &vaf);
 610         va_end(args);
 611
 612         if ((sb->s_flags & MS_RDONLY) == 0) {
 613                 ext4_msg(sb, KERN_CRIT, "Remounting filesystem read-only");
 614                 EXT4_SB(sb)->s_mount_flags |= EXT4_MF_FS_ABORTED;
 615                 /*
 616                  * Make sure updated value of ->s_mount_flags will be visible
 617                  * before ->s_flags update
 618                  */
 619                 smp_wmb();
 620                 sb->s_flags |= MS_RDONLY;
 621                 if (EXT4_SB(sb)->s_journal)
 622                         jbd2_journal_abort(EXT4_SB(sb)->s_journal, -EIO);
 623                 save_error_info(sb, function, line);
 624         }
 625         if (test_opt(sb, ERRORS_PANIC)) {
 626                 if (EXT4_SB(sb)->s_journal &&
 627                   !(EXT4_SB(sb)->s_journal->j_flags & JBD2_REC_ERR))
 628                         return;
 629                 panic("EXT4-fs panic from previous error\n");
 630         }
 631 }
 632
 633 void __ext4_msg(struct super_block *sb,
 634                 const char *prefix, const char *fmt, ...)
 635 {
 636         struct va_format vaf;
 637         va_list args;
 638
 639         if (!___ratelimit(&(EXT4_SB(sb)->s_msg_ratelimit_state), "EXT4-fs"))
 640                 return;
 641
 642         va_start(args, fmt);
 643         vaf.fmt = fmt;
 644         vaf.va = &args;
 645         printk("%sEXT4-fs (%s): %pV\n", prefix, sb->s_id, &vaf);
 646         va_end(args);
 647 }
 648
 649 #define ext4_warning_ratelimit(sb)                                      \
 650                 ___ratelimit(&(EXT4_SB(sb)->s_warning_ratelimit_state), \
 651                              "EXT4-fs warning")
 652
 653 void __ext4_warning(struct super_block *sb, const char *function,
 654                     unsigned int line, const char *fmt, ...)
 655 {
 656         struct va_format vaf;
 657         va_list args;
 658
 659         if (!ext4_warning_ratelimit(sb))
 660                 return;
 661
 662         va_start(args, fmt);
 663         vaf.fmt = fmt;
 664         vaf.va = &args;
 665         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: %pV\n",
 666                sb->s_id, function, line, &vaf);
 667         va_end(args);
 668 }
 669
 670 void __ext4_warning_inode(const struct inode *inode, const char *function,
 671                           unsigned int line, const char *fmt, ...)
 672 {
 673         struct va_format vaf;
 674         va_list args;
 675
 676         if (!ext4_warning_ratelimit(inode->i_sb))
 677                 return;
 678
 679         va_start(args, fmt);
 680         vaf.fmt = fmt;
 681         vaf.va = &args;
 682         printk(KERN_WARNING "EXT4-fs warning (device %s): %s:%d: "
 683                "inode #%lu: comm %s: %pV\n", inode->i_sb->s_id,
 684                function, line, inode->i_ino, current->comm, &vaf);
 685         va_end(args);
 686 }
 687
 688 void __ext4_grp_locked_error(const char *function, unsigned int line,
 689                              struct super_block *sb, ext4_group_t grp,
 690                              unsigned long ino, ext4_fsblk_t block,
 691                              const char *fmt, ...)
 692 __releases(bitlock)
 693 __acquires(bitlock)
 694 {
 695         struct va_format vaf;
 696         va_list args;
 697         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 698
 699         es->s_last_error_ino = cpu_to_le32(ino);
 700         es->s_last_error_block = cpu_to_le64(block);
 701         __save_error_info(sb, function, line);
 702
 703         if (ext4_error_ratelimit(sb)) {
 704                 va_start(args, fmt);
 705                 vaf.fmt = fmt;
 706                 vaf.va = &args;
 707                 printk(KERN_CRIT "EXT4-fs error (device %s): %s:%d: group %u, ",
 708                        sb->s_id, function, line, grp);
 709                 if (ino)
 710                         printk(KERN_CONT "inode %lu: ", ino);
 711                 if (block)
 712                         printk(KERN_CONT "block %llu:",
 713                                (unsigned long long) block);
 714                 printk(KERN_CONT "%pV\n", &vaf);
 715                 va_end(args);
 716         }
 717
 718         if (test_opt(sb, ERRORS_CONT)) {
 719                 ext4_commit_super(sb, 0);
 720                 return;
 721         }
 722
 723         ext4_unlock_group(sb, grp);
 724         ext4_commit_super(sb, 1);
 725         ext4_handle_error(sb);
 726         /*
 727          * We only get here in the ERRORS_RO case; relocking the group
 728          * may be dangerous, but nothing bad will happen since the
 729          * filesystem will have already been marked read/only and the
 730          * journal has been aborted.  We return 1 as a hint to callers
 731          * who might what to use the return value from
 732          * ext4_grp_locked_error() to distinguish between the
 733          * ERRORS_CONT and ERRORS_RO case, and perhaps return more
 734          * aggressively from the ext4 function in question, with a
 735          * more appropriate error code.
 736          */
 737         ext4_lock_group(sb, grp);
 738         return;
 739 }
 740
 741 void ext4_update_dynamic_rev(struct super_block *sb)
 742 {
 743         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
 744
 745         if (le32_to_cpu(es->s_rev_level) > EXT4_GOOD_OLD_REV)
 746                 return;
 747
 748         ext4_warning(sb,
 749                      "updating to rev %d because of new feature flag, "
 750                      "running e2fsck is recommended",
 751                      EXT4_DYNAMIC_REV);
 752
 753         es->s_first_ino = cpu_to_le32(EXT4_GOOD_OLD_FIRST_INO);
 754         es->s_inode_size = cpu_to_le16(EXT4_GOOD_OLD_INODE_SIZE);
 755         es->s_rev_level = cpu_to_le32(EXT4_DYNAMIC_REV);
 756         /* leave es->s_feature_*compat flags alone */
 757         /* es->s_uuid will be set by e2fsck if empty */
 758
 759         /*
 760          * The rest of the superblock fields should be zero, and if not it
 761          * means they are likely already in use, so leave them alone.  We
 762          * can leave it up to e2fsck to clean up any inconsistencies there.
 763          */
 764 }
 765
 766 /*
 767  * Open the external journal device
 768  */
 769 static struct block_device *ext4_blkdev_get(dev_t dev, struct super_block *sb)
 770 {
 771         struct block_device *bdev;
 772         char b[BDEVNAME_SIZE];
 773
 774         bdev = blkdev_get_by_dev(dev, FMODE_READ|FMODE_WRITE|FMODE_EXCL, sb);
 775         if (IS_ERR(bdev))
 776                 goto fail;
 777         return bdev;
 778
 779 fail:
 780         ext4_msg(sb, KERN_ERR, "failed to open journal device %s: %ld",
 781                         __bdevname(dev, b), PTR_ERR(bdev));
 782         return NULL;
 783 }
 784
 785 /*
 786  * Release the journal device
 787  */
 788 static void ext4_blkdev_put(struct block_device *bdev)
 789 {
 790         blkdev_put(bdev, FMODE_READ|FMODE_WRITE|FMODE_EXCL);
 791 }
 792
 793 static void ext4_blkdev_remove(struct ext4_sb_info *sbi)
 794 {
 795         struct block_device *bdev;
 796         bdev = sbi->journal_bdev;
 797         if (bdev) {
 798                 ext4_blkdev_put(bdev);
 799                 sbi->journal_bdev = NULL;
 800         }
 801 }
 802
 803 static inline struct inode *orphan_list_entry(struct list_head *l)
 804 {
 805         return &list_entry(l, struct ext4_inode_info, i_orphan)->vfs_inode;
 806 }
 807
 808 static void dump_orphan_list(struct super_block *sb, struct ext4_sb_info *sbi)
 809 {
 810         struct list_head *l;
 811
 812         ext4_msg(sb, KERN_ERR, "sb orphan head is %d",
 813                  le32_to_cpu(sbi->s_es->s_last_orphan));
 814
 815         printk(KERN_ERR "sb_info orphan list:\n");
 816         list_for_each(l, &sbi->s_orphan) {
 817                 struct inode *inode = orphan_list_entry(l);
 818                 printk(KERN_ERR "  "
 819                        "inode %s:%lu at %p: mode %o, nlink %d, next %d\n",
 820                        inode->i_sb->s_id, inode->i_ino, inode,
 821                        inode->i_mode, inode->i_nlink,
 822                        NEXT_ORPHAN(inode));
 823         }
 824 }
 825
 826 static void ext4_put_super(struct super_block *sb)
 827 {
 828         struct ext4_sb_info *sbi = EXT4_SB(sb);
 829         struct ext4_super_block *es = sbi->s_es;
 830         struct buffer_head **group_desc;
 831         struct flex_groups **flex_groups;
 832         int aborted = 0;
 833         int i, err;
 834
 835         ext4_unregister_li_request(sb);
 836         dquot_disable(sb, -1, DQUOT_USAGE_ENABLED | DQUOT_LIMITS_ENABLED);
 837
 838         flush_workqueue(sbi->rsv_conversion_wq);
 839         destroy_workqueue(sbi->rsv_conversion_wq);
 840
 841         if (sbi->s_journal) {
 842                 aborted = is_journal_aborted(sbi->s_journal);
 843                 err = jbd2_journal_destroy(sbi->s_journal);
 844                 sbi->s_journal = NULL;
 845                 if ((err < 0) && !aborted)
 846                         ext4_abort(sb, "Couldn't clean up the journal");
 847         }
 848
 849         ext4_unregister_sysfs(sb);
 850         ext4_es_unregister_shrinker(sbi);
 851         del_timer_sync(&sbi->s_err_report);
 852         ext4_release_system_zone(sb);
 853         ext4_mb_release(sb);
 854         ext4_ext_release(sb);
 855
 856         if (!(sb->s_flags & MS_RDONLY) && !aborted) {
 857                 ext4_clear_feature_journal_needs_recovery(sb);
 858                 es->s_state = cpu_to_le16(sbi->s_mount_state);
 859         }
 860         if (!(sb->s_flags & MS_RDONLY))
 861                 ext4_commit_super(sb, 1);
 862
 863         rcu_read_lock();
 864         group_desc = rcu_dereference(sbi->s_group_desc);
 865         for (i = 0; i < sbi->s_gdb_count; i++)
 866                 brelse(group_desc[i]);
 867         kvfree(group_desc);
 868         flex_groups = rcu_dereference(sbi->s_flex_groups);
 869         if (flex_groups) {
 870                 for (i = 0; i < sbi->s_flex_groups_allocated; i++)
 871                         kvfree(flex_groups[i]);
 872                 kvfree(flex_groups);
 873         }
 874         rcu_read_unlock();
 875         percpu_counter_destroy(&sbi->s_freeclusters_counter);
 876         percpu_counter_destroy(&sbi->s_freeinodes_counter);
 877         percpu_counter_destroy(&sbi->s_dirs_counter);
 878         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
 879         percpu_free_rwsem(&sbi->s_writepages_rwsem);
 880         brelse(sbi->s_sbh);
 881 #ifdef CONFIG_QUOTA
 882         for (i = 0; i < EXT4_MAXQUOTAS; i++)
 883                 kfree(sbi->s_qf_names[i]);
 884 #endif
 885
 886         /* Debugging code just in case the in-memory inode orphan list
 887          * isn't empty.  The on-disk one can be non-empty if we've
 888          * detected an error and taken the fs readonly, but the
 889          * in-memory list had better be clean by this point. */
 890         if (!list_empty(&sbi->s_orphan))
 891                 dump_orphan_list(sb, sbi);
 892         J_ASSERT(list_empty(&sbi->s_orphan));
 893
 894         sync_blockdev(sb->s_bdev);
 895         invalidate_bdev(sb->s_bdev);
 896         if (sbi->journal_bdev && sbi->journal_bdev != sb->s_bdev) {
 897                 /*
 898                  * Invalidate the journal device's buffers.  We don't want them
 899                  * floating about in memory - the physical journal device may
 900                  * hotswapped, and it breaks the `ro-after' testing code.
 901                  */
 902                 sync_blockdev(sbi->journal_bdev);
 903                 invalidate_bdev(sbi->journal_bdev);
 904                 ext4_blkdev_remove(sbi);
 905         }
 906         if (sbi->s_mb_cache) {
 907                 ext4_xattr_destroy_cache(sbi->s_mb_cache);
 908                 sbi->s_mb_cache = NULL;
 909         }
 910         if (sbi->s_mmp_tsk)
 911                 kthread_stop(sbi->s_mmp_tsk);
 912         sb->s_fs_info = NULL;
 913         /*
 914          * Now that we are completely done shutting down the
 915          * superblock, we need to actually destroy the kobject.
 916          */
 917         kobject_put(&sbi->s_kobj);
 918         wait_for_completion(&sbi->s_kobj_unregister);
 919         if (sbi->s_chksum_driver)
 920                 crypto_free_shash(sbi->s_chksum_driver);
 921         kfree(sbi->s_blockgroup_lock);
 922         kfree(sbi);
 923 }
 924
 925 static struct kmem_cache *ext4_inode_cachep;
 926
 927 /*
 928  * Called inside transaction, so use GFP_NOFS
 929  */
 930 static struct inode *ext4_alloc_inode(struct super_block *sb)
 931 {
 932         struct ext4_inode_info *ei;
 933
 934         ei = kmem_cache_alloc(ext4_inode_cachep, GFP_NOFS);
 935         if (!ei)
 936                 return NULL;
 937
 938         ei->vfs_inode.i_version = 1;
 939         spin_lock_init(&ei->i_raw_lock);
 940         INIT_LIST_HEAD(&ei->i_prealloc_list);
 941         spin_lock_init(&ei->i_prealloc_lock);
 942         ext4_es_init_tree(&ei->i_es_tree);
 943         rwlock_init(&ei->i_es_lock);
 944         INIT_LIST_HEAD(&ei->i_es_list);
 945         ei->i_es_all_nr = 0;
 946         ei->i_es_shk_nr = 0;
 947         ei->i_es_shrink_lblk = 0;
 948         ei->i_reserved_data_blocks = 0;
 949         ei->i_reserved_meta_blocks = 0;
 950         ei->i_allocated_meta_blocks = 0;
 951         ei->i_da_metadata_calc_len = 0;
 952         ei->i_da_metadata_calc_last_lblock = 0;
 953         spin_lock_init(&(ei->i_block_reservation_lock));
 954 #ifdef CONFIG_QUOTA
 955         ei->i_reserved_quota = 0;
 956         memset(&ei->i_dquot, 0, sizeof(ei->i_dquot));
 957 #endif
 958         ei->jinode = NULL;
 959         INIT_LIST_HEAD(&ei->i_rsv_conversion_list);
 960         spin_lock_init(&ei->i_completed_io_lock);
 961         ei->i_sync_tid = 0;
 962         ei->i_datasync_tid = 0;
 963         atomic_set(&ei->i_unwritten, 0);
 964         INIT_WORK(&ei->i_rsv_conversion_work, ext4_end_io_rsv_work);
 965         return &ei->vfs_inode;
 966 }
 967
 968 static int ext4_drop_inode(struct inode *inode)
 969 {
 970         int drop = generic_drop_inode(inode);
 971
 972         trace_ext4_drop_inode(inode, drop);
 973         return drop;
 974 }
 975
 976 static void ext4_i_callback(struct rcu_head *head)
 977 {
 978         struct inode *inode = container_of(head, struct inode, i_rcu);
 979         kmem_cache_free(ext4_inode_cachep, EXT4_I(inode));
 980 }
 981
 982 static void ext4_destroy_inode(struct inode *inode)
 983 {
 984         if (!list_empty(&(EXT4_I(inode)->i_orphan))) {
 985                 ext4_msg(inode->i_sb, KERN_ERR,
 986                          "Inode %lu (%p): orphan list check failed!",
 987                          inode->i_ino, EXT4_I(inode));
 988                 print_hex_dump(KERN_INFO, "", DUMP_PREFIX_ADDRESS, 16, 4,
 989                                 EXT4_I(inode), sizeof(struct ext4_inode_info),
 990                                 true);
 991                 dump_stack();
 992         }
 993         call_rcu(&inode->i_rcu, ext4_i_callback);
 994 }
 995
 996 static void init_once(void *foo)
 997 {
 998         struct ext4_inode_info *ei = (struct ext4_inode_info *) foo;
 999
1000         INIT_LIST_HEAD(&ei->i_orphan);
1001         init_rwsem(&ei->xattr_sem);
1002         init_rwsem(&ei->i_data_sem);
1003         init_rwsem(&ei->i_mmap_sem);
1004         inode_init_once(&ei->vfs_inode);
1005 }
1006
1007 static int __init init_inodecache(void)
1008 {
1009         ext4_inode_cachep = kmem_cache_create("ext4_inode_cache",
1010                                              sizeof(struct ext4_inode_info),
1011                                              0, (SLAB_RECLAIM_ACCOUNT|
1012                                                 SLAB_MEM_SPREAD|SLAB_ACCOUNT),
1013                                              init_once);
1014         if (ext4_inode_cachep == NULL)
1015                 return -ENOMEM;
1016         return 0;
1017 }
1018
1019 static void destroy_inodecache(void)
1020 {
1021         /*
1022          * Make sure all delayed rcu free inodes are flushed before we
1023          * destroy cache.
1024          */
1025         rcu_barrier();
1026         kmem_cache_destroy(ext4_inode_cachep);
1027 }
1028
1029 void ext4_clear_inode(struct inode *inode)
1030 {
1031         invalidate_inode_buffers(inode);
1032         clear_inode(inode);
1033         dquot_drop(inode);
1034         ext4_discard_preallocations(inode);
1035         ext4_es_remove_extent(inode, 0, EXT_MAX_BLOCKS);
1036         if (EXT4_I(inode)->jinode) {
1037                 jbd2_journal_release_jbd_inode(EXT4_JOURNAL(inode),
1038                                                EXT4_I(inode)->jinode);
1039                 jbd2_free_inode(EXT4_I(inode)->jinode);
1040                 EXT4_I(inode)->jinode = NULL;
1041         }
1042 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1043         fscrypt_put_encryption_info(inode, NULL);
1044 #endif
1045 }
1046
1047 static struct inode *ext4_nfs_get_inode(struct super_block *sb,
1048                                         u64 ino, u32 generation)
1049 {
1050         struct inode *inode;
1051
1052         /*
1053          * Currently we don't know the generation for parent directory, so
1054          * a generation of 0 means "accept any"
1055          */
1056         inode = ext4_iget(sb, ino, EXT4_IGET_HANDLE);
1057         if (IS_ERR(inode))
1058                 return ERR_CAST(inode);
1059         if (generation && inode->i_generation != generation) {
1060                 iput(inode);
1061                 return ERR_PTR(-ESTALE);
1062         }
1063
1064         return inode;
1065 }
1066
1067 static struct dentry *ext4_fh_to_dentry(struct super_block *sb, struct fid *fid,
1068                                         int fh_len, int fh_type)
1069 {
1070         return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
1071                                     ext4_nfs_get_inode);
1072 }
1073
1074 static struct dentry *ext4_fh_to_parent(struct super_block *sb, struct fid *fid,
1075                                         int fh_len, int fh_type)
1076 {
1077         return generic_fh_to_parent(sb, fid, fh_len, fh_type,
1078                                     ext4_nfs_get_inode);
1079 }
1080
1081 static int ext4_nfs_commit_metadata(struct inode *inode)
1082 {
1083         struct writeback_control wbc = {
1084                 .sync_mode = WB_SYNC_ALL
1085         };
1086
1087         trace_ext4_nfs_commit_metadata(inode);
1088         return ext4_write_inode(inode, &wbc);
1089 }
1090
1091 /*
1092  * Try to release metadata pages (indirect blocks, directories) which are
1093  * mapped via the block device.  Since these pages could have journal heads
1094  * which would prevent try_to_free_buffers() from freeing them, we must use
1095  * jbd2 layer's try_to_free_buffers() function to release them.
1096  */
1097 static int bdev_try_to_free_page(struct super_block *sb, struct page *page,
1098                                  gfp_t wait)
1099 {
1100         journal_t *journal = EXT4_SB(sb)->s_journal;
1101
1102         WARN_ON(PageChecked(page));
1103         if (!page_has_buffers(page))
1104                 return 0;
1105         if (journal)
1106                 return jbd2_journal_try_to_free_buffers(journal, page,
1107                                                 wait & ~__GFP_DIRECT_RECLAIM);
1108         return try_to_free_buffers(page);
1109 }
1110
1111 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1112 static int ext4_get_context(struct inode *inode, void *ctx, size_t len)
1113 {
1114         return ext4_xattr_get(inode, EXT4_XATTR_INDEX_ENCRYPTION,
1115                                  EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx, len);
1116 }
1117
1118 static int ext4_key_prefix(struct inode *inode, u8 **key)
1119 {
1120         *key = EXT4_SB(inode->i_sb)->key_prefix;
1121         return EXT4_SB(inode->i_sb)->key_prefix_size;
1122 }
1123
1124 static int ext4_prepare_context(struct inode *inode)
1125 {
1126         return ext4_convert_inline_data(inode);
1127 }
1128
1129 static int ext4_set_context(struct inode *inode, const void *ctx, size_t len,
1130                                                         void *fs_data)
1131 {
1132         handle_t *handle;
1133         int res, res2;
1134
1135         /* fs_data is null when internally used. */
1136         if (fs_data) {
1137                 res  = ext4_xattr_set(inode, EXT4_XATTR_INDEX_ENCRYPTION,
1138                                 EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx,
1139                                 len, 0);
1140                 if (!res) {
1141                         ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1142                         ext4_clear_inode_state(inode,
1143                                         EXT4_STATE_MAY_INLINE_DATA);
1144                 }
1145                 return res;
1146         }
1147
1148         handle = ext4_journal_start(inode, EXT4_HT_MISC,
1149                         ext4_jbd2_credits_xattr(inode));
1150         if (IS_ERR(handle))
1151                 return PTR_ERR(handle);
1152
1153         res = ext4_xattr_set(inode, EXT4_XATTR_INDEX_ENCRYPTION,
1154                         EXT4_XATTR_NAME_ENCRYPTION_CONTEXT, ctx,
1155                         len, 0);
1156         if (!res) {
1157                 ext4_set_inode_flag(inode, EXT4_INODE_ENCRYPT);
1158                 res = ext4_mark_inode_dirty(handle, inode);
1159                 if (res)
1160                         EXT4_ERROR_INODE(inode, "Failed to mark inode dirty");
1161         }
1162         res2 = ext4_journal_stop(handle);
1163         if (!res)
1164                 res = res2;
1165         return res;
1166 }
1167
1168 static int ext4_dummy_context(struct inode *inode)
1169 {
1170         return DUMMY_ENCRYPTION_ENABLED(EXT4_SB(inode->i_sb));
1171 }
1172
1173 static unsigned ext4_max_namelen(struct inode *inode)
1174 {
1175         return S_ISLNK(inode->i_mode) ? inode->i_sb->s_blocksize :
1176                 EXT4_NAME_LEN;
1177 }
1178
1179 static struct fscrypt_operations ext4_cryptops = {
1180         .get_context            = ext4_get_context,
1181         .key_prefix             = ext4_key_prefix,
1182         .prepare_context        = ext4_prepare_context,
1183         .set_context            = ext4_set_context,
1184         .dummy_context          = ext4_dummy_context,
1185         .is_encrypted           = ext4_encrypted_inode,
1186         .empty_dir              = ext4_empty_dir,
1187         .max_namelen            = ext4_max_namelen,
1188 };
1189 #else
1190 static struct fscrypt_operations ext4_cryptops = {
1191         .is_encrypted           = ext4_encrypted_inode,
1192 };
1193 #endif
1194
1195 #ifdef CONFIG_QUOTA
1196 static char *quotatypes[] = INITQFNAMES;
1197 #define QTYPE2NAME(t) (quotatypes[t])
1198
1199 static int ext4_write_dquot(struct dquot *dquot);
1200 static int ext4_acquire_dquot(struct dquot *dquot);
1201 static int ext4_release_dquot(struct dquot *dquot);
1202 static int ext4_mark_dquot_dirty(struct dquot *dquot);
1203 static int ext4_write_info(struct super_block *sb, int type);
1204 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
1205                          struct path *path);
1206 static int ext4_quota_off(struct super_block *sb, int type);
1207 static int ext4_quota_on_mount(struct super_block *sb, int type);
1208 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
1209                                size_t len, loff_t off);
1210 static ssize_t ext4_quota_write(struct super_block *sb, int type,
1211                                 const char *data, size_t len, loff_t off);
1212 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
1213                              unsigned int flags);
1214 static int ext4_enable_quotas(struct super_block *sb);
1215 static int ext4_get_next_id(struct super_block *sb, struct kqid *qid);
1216
1217 static struct dquot **ext4_get_dquots(struct inode *inode)
1218 {
1219         return EXT4_I(inode)->i_dquot;
1220 }
1221
1222 static const struct dquot_operations ext4_quota_operations = {
1223         .get_reserved_space = ext4_get_reserved_space,
1224         .write_dquot    = ext4_write_dquot,
1225         .acquire_dquot  = ext4_acquire_dquot,
1226         .release_dquot  = ext4_release_dquot,
1227         .mark_dirty     = ext4_mark_dquot_dirty,
1228         .write_info     = ext4_write_info,
1229         .alloc_dquot    = dquot_alloc,
1230         .destroy_dquot  = dquot_destroy,
1231         .get_projid     = ext4_get_projid,
1232         .get_next_id    = ext4_get_next_id,
1233 };
1234
1235 static const struct quotactl_ops ext4_qctl_operations = {
1236         .quota_on       = ext4_quota_on,
1237         .quota_off      = ext4_quota_off,
1238         .quota_sync     = dquot_quota_sync,
1239         .get_state      = dquot_get_state,
1240         .set_info       = dquot_set_dqinfo,
1241         .get_dqblk      = dquot_get_dqblk,
1242         .set_dqblk      = dquot_set_dqblk,
1243         .get_nextdqblk  = dquot_get_next_dqblk,
1244 };
1245 #endif
1246
1247 static const struct super_operations ext4_sops = {
1248         .alloc_inode    = ext4_alloc_inode,
1249         .destroy_inode  = ext4_destroy_inode,
1250         .write_inode    = ext4_write_inode,
1251         .dirty_inode    = ext4_dirty_inode,
1252         .drop_inode     = ext4_drop_inode,
1253         .evict_inode    = ext4_evict_inode,
1254         .put_super      = ext4_put_super,
1255         .sync_fs        = ext4_sync_fs,
1256         .freeze_fs      = ext4_freeze,
1257         .unfreeze_fs    = ext4_unfreeze,
1258         .statfs         = ext4_statfs,
1259         .remount_fs     = ext4_remount,
1260         .show_options   = ext4_show_options,
1261 #ifdef CONFIG_QUOTA
1262         .quota_read     = ext4_quota_read,
1263         .quota_write    = ext4_quota_write,
1264         .get_dquots     = ext4_get_dquots,
1265 #endif
1266         .bdev_try_to_free_page = bdev_try_to_free_page,
1267 };
1268
1269 static const struct export_operations ext4_export_ops = {
1270         .fh_to_dentry = ext4_fh_to_dentry,
1271         .fh_to_parent = ext4_fh_to_parent,
1272         .get_parent = ext4_get_parent,
1273         .commit_metadata = ext4_nfs_commit_metadata,
1274 };
1275
1276 enum {
1277         Opt_bsd_df, Opt_minix_df, Opt_grpid, Opt_nogrpid,
1278         Opt_resgid, Opt_resuid, Opt_sb, Opt_err_cont, Opt_err_panic, Opt_err_ro,
1279         Opt_nouid32, Opt_debug, Opt_removed,
1280         Opt_user_xattr, Opt_nouser_xattr, Opt_acl, Opt_noacl,
1281         Opt_auto_da_alloc, Opt_noauto_da_alloc, Opt_noload,
1282         Opt_commit, Opt_min_batch_time, Opt_max_batch_time, Opt_journal_dev,
1283         Opt_journal_path, Opt_journal_checksum, Opt_journal_async_commit,
1284         Opt_abort, Opt_data_journal, Opt_data_ordered, Opt_data_writeback,
1285         Opt_data_err_abort, Opt_data_err_ignore, Opt_test_dummy_encryption,
1286         Opt_usrjquota, Opt_grpjquota, Opt_offusrjquota, Opt_offgrpjquota,
1287         Opt_jqfmt_vfsold, Opt_jqfmt_vfsv0, Opt_jqfmt_vfsv1, Opt_quota,
1288         Opt_noquota, Opt_barrier, Opt_nobarrier, Opt_err,
1289         Opt_usrquota, Opt_grpquota, Opt_prjquota, Opt_i_version, Opt_dax,
1290         Opt_stripe, Opt_delalloc, Opt_nodelalloc, Opt_mblk_io_submit,
1291         Opt_lazytime, Opt_nolazytime,
1292         Opt_nomblk_io_submit, Opt_block_validity, Opt_noblock_validity,
1293         Opt_inode_readahead_blks, Opt_journal_ioprio,
1294         Opt_dioread_nolock, Opt_dioread_lock,
1295         Opt_discard, Opt_nodiscard, Opt_init_itable, Opt_noinit_itable,
1296         Opt_max_dir_size_kb, Opt_nojournal_checksum,
1297 };
1298
1299 static const match_table_t tokens = {
1300         {Opt_bsd_df, "bsddf"},
1301         {Opt_minix_df, "minixdf"},
1302         {Opt_grpid, "grpid"},
1303         {Opt_grpid, "bsdgroups"},
1304         {Opt_nogrpid, "nogrpid"},
1305         {Opt_nogrpid, "sysvgroups"},
1306         {Opt_resgid, "resgid=%u"},
1307         {Opt_resuid, "resuid=%u"},
1308         {Opt_sb, "sb=%u"},
1309         {Opt_err_cont, "errors=continue"},
1310         {Opt_err_panic, "errors=panic"},
1311         {Opt_err_ro, "errors=remount-ro"},
1312         {Opt_nouid32, "nouid32"},
1313         {Opt_debug, "debug"},
1314         {Opt_removed, "oldalloc"},
1315         {Opt_removed, "orlov"},
1316         {Opt_user_xattr, "user_xattr"},
1317         {Opt_nouser_xattr, "nouser_xattr"},
1318         {Opt_acl, "acl"},
1319         {Opt_noacl, "noacl"},
1320         {Opt_noload, "norecovery"},
1321         {Opt_noload, "noload"},
1322         {Opt_removed, "nobh"},
1323         {Opt_removed, "bh"},
1324         {Opt_commit, "commit=%u"},
1325         {Opt_min_batch_time, "min_batch_time=%u"},
1326         {Opt_max_batch_time, "max_batch_time=%u"},
1327         {Opt_journal_dev, "journal_dev=%u"},
1328         {Opt_journal_path, "journal_path=%s"},
1329         {Opt_journal_checksum, "journal_checksum"},
1330         {Opt_nojournal_checksum, "nojournal_checksum"},
1331         {Opt_journal_async_commit, "journal_async_commit"},
1332         {Opt_abort, "abort"},
1333         {Opt_data_journal, "data=journal"},
1334         {Opt_data_ordered, "data=ordered"},
1335         {Opt_data_writeback, "data=writeback"},
1336         {Opt_data_err_abort, "data_err=abort"},
1337         {Opt_data_err_ignore, "data_err=ignore"},
1338         {Opt_offusrjquota, "usrjquota="},
1339         {Opt_usrjquota, "usrjquota=%s"},
1340         {Opt_offgrpjquota, "grpjquota="},
1341         {Opt_grpjquota, "grpjquota=%s"},
1342         {Opt_jqfmt_vfsold, "jqfmt=vfsold"},
1343         {Opt_jqfmt_vfsv0, "jqfmt=vfsv0"},
1344         {Opt_jqfmt_vfsv1, "jqfmt=vfsv1"},
1345         {Opt_grpquota, "grpquota"},
1346         {Opt_noquota, "noquota"},
1347         {Opt_quota, "quota"},
1348         {Opt_usrquota, "usrquota"},
1349         {Opt_prjquota, "prjquota"},
1350         {Opt_barrier, "barrier=%u"},
1351         {Opt_barrier, "barrier"},
1352         {Opt_nobarrier, "nobarrier"},
1353         {Opt_i_version, "i_version"},
1354         {Opt_dax, "dax"},
1355         {Opt_stripe, "stripe=%u"},
1356         {Opt_delalloc, "delalloc"},
1357         {Opt_lazytime, "lazytime"},
1358         {Opt_nolazytime, "nolazytime"},
1359         {Opt_nodelalloc, "nodelalloc"},
1360         {Opt_removed, "mblk_io_submit"},
1361         {Opt_removed, "nomblk_io_submit"},
1362         {Opt_block_validity, "block_validity"},
1363         {Opt_noblock_validity, "noblock_validity"},
1364         {Opt_inode_readahead_blks, "inode_readahead_blks=%u"},
1365         {Opt_journal_ioprio, "journal_ioprio=%u"},
1366         {Opt_auto_da_alloc, "auto_da_alloc=%u"},
1367         {Opt_auto_da_alloc, "auto_da_alloc"},
1368         {Opt_noauto_da_alloc, "noauto_da_alloc"},
1369         {Opt_dioread_nolock, "dioread_nolock"},
1370         {Opt_dioread_lock, "dioread_lock"},
1371         {Opt_discard, "discard"},
1372         {Opt_nodiscard, "nodiscard"},
1373         {Opt_init_itable, "init_itable=%u"},
1374         {Opt_init_itable, "init_itable"},
1375         {Opt_noinit_itable, "noinit_itable"},
1376         {Opt_max_dir_size_kb, "max_dir_size_kb=%u"},
1377         {Opt_test_dummy_encryption, "test_dummy_encryption"},
1378         {Opt_removed, "check=none"},    /* mount option from ext2/3 */
1379         {Opt_removed, "nocheck"},       /* mount option from ext2/3 */
1380         {Opt_removed, "reservation"},   /* mount option from ext2/3 */
1381         {Opt_removed, "noreservation"}, /* mount option from ext2/3 */
1382         {Opt_removed, "journal=%u"},    /* mount option from ext2/3 */
1383         {Opt_err, NULL},
1384 };
1385
1386 static ext4_fsblk_t get_sb_block(void **data)
1387 {
1388         ext4_fsblk_t    sb_block;
1389         char            *options = (char *) *data;
1390
1391         if (!options || strncmp(options, "sb=", 3) != 0)
1392                 return 1;       /* Default location */
1393
1394         options += 3;
1395         /* TODO: use simple_strtoll with >32bit ext4 */
1396         sb_block = simple_strtoul(options, &options, 0);
1397         if (*options && *options != ',') {
1398                 printk(KERN_ERR "EXT4-fs: Invalid sb specification: %s\n",
1399                        (char *) *data);
1400                 return 1;
1401         }
1402         if (*options == ',')
1403                 options++;
1404         *data = (void *) options;
1405
1406         return sb_block;
1407 }
1408
1409 #define DEFAULT_JOURNAL_IOPRIO (IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, 3))
1410 static char deprecated_msg[] = "Mount option \"%s\" will be removed by %s\n"
1411         "Contact linux-ext4@vger.kernel.org if you think we should keep it.\n";
1412
1413 #ifdef CONFIG_QUOTA
1414 static int set_qf_name(struct super_block *sb, int qtype, substring_t *args)
1415 {
1416         struct ext4_sb_info *sbi = EXT4_SB(sb);
1417         char *qname;
1418         int ret = -1;
1419
1420         if (sb_any_quota_loaded(sb) &&
1421                 !sbi->s_qf_names[qtype]) {
1422                 ext4_msg(sb, KERN_ERR,
1423                         "Cannot change journaled "
1424                         "quota options when quota turned on");
1425                 return -1;
1426         }
1427         if (ext4_has_feature_quota(sb)) {
1428                 ext4_msg(sb, KERN_INFO, "Journaled quota options "
1429                          "ignored when QUOTA feature is enabled");
1430                 return 1;
1431         }
1432         qname = match_strdup(args);
1433         if (!qname) {
1434                 ext4_msg(sb, KERN_ERR,
1435                         "Not enough memory for storing quotafile name");
1436                 return -1;
1437         }
1438         if (sbi->s_qf_names[qtype]) {
1439                 if (strcmp(sbi->s_qf_names[qtype], qname) == 0)
1440                         ret = 1;
1441                 else
1442                         ext4_msg(sb, KERN_ERR,
1443                                  "%s quota file already specified",
1444                                  QTYPE2NAME(qtype));
1445                 goto errout;
1446         }
1447         if (strchr(qname, '/')) {
1448                 ext4_msg(sb, KERN_ERR,
1449                         "quotafile must be on filesystem root");
1450                 goto errout;
1451         }
1452         sbi->s_qf_names[qtype] = qname;
1453         set_opt(sb, QUOTA);
1454         return 1;
1455 errout:
1456         kfree(qname);
1457         return ret;
1458 }
1459
1460 static int clear_qf_name(struct super_block *sb, int qtype)
1461 {
1462
1463         struct ext4_sb_info *sbi = EXT4_SB(sb);
1464
1465         if (sb_any_quota_loaded(sb) &&
1466                 sbi->s_qf_names[qtype]) {
1467                 ext4_msg(sb, KERN_ERR, "Cannot change journaled quota options"
1468                         " when quota turned on");
1469                 return -1;
1470         }
1471         kfree(sbi->s_qf_names[qtype]);
1472         sbi->s_qf_names[qtype] = NULL;
1473         return 1;
1474 }
1475 #endif
1476
1477 #define MOPT_SET        0x0001
1478 #define MOPT_CLEAR      0x0002
1479 #define MOPT_NOSUPPORT  0x0004
1480 #define MOPT_EXPLICIT   0x0008
1481 #define MOPT_CLEAR_ERR  0x0010
1482 #define MOPT_GTE0       0x0020
1483 #ifdef CONFIG_QUOTA
1484 #define MOPT_Q          0
1485 #define MOPT_QFMT       0x0040
1486 #else
1487 #define MOPT_Q          MOPT_NOSUPPORT
1488 #define MOPT_QFMT       MOPT_NOSUPPORT
1489 #endif
1490 #define MOPT_DATAJ      0x0080
1491 #define MOPT_NO_EXT2    0x0100
1492 #define MOPT_NO_EXT3    0x0200
1493 #define MOPT_EXT4_ONLY  (MOPT_NO_EXT2 | MOPT_NO_EXT3)
1494 #define MOPT_STRING     0x0400
1495
1496 static const struct mount_opts {
1497         int     token;
1498         int     mount_opt;
1499         int     flags;
1500 } ext4_mount_opts[] = {
1501         {Opt_minix_df, EXT4_MOUNT_MINIX_DF, MOPT_SET},
1502         {Opt_bsd_df, EXT4_MOUNT_MINIX_DF, MOPT_CLEAR},
1503         {Opt_grpid, EXT4_MOUNT_GRPID, MOPT_SET},
1504         {Opt_nogrpid, EXT4_MOUNT_GRPID, MOPT_CLEAR},
1505         {Opt_block_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_SET},
1506         {Opt_noblock_validity, EXT4_MOUNT_BLOCK_VALIDITY, MOPT_CLEAR},
1507         {Opt_dioread_nolock, EXT4_MOUNT_DIOREAD_NOLOCK,
1508          MOPT_EXT4_ONLY | MOPT_SET},
1509         {Opt_dioread_lock, EXT4_MOUNT_DIOREAD_NOLOCK,
1510          MOPT_EXT4_ONLY | MOPT_CLEAR},
1511         {Opt_discard, EXT4_MOUNT_DISCARD, MOPT_SET},
1512         {Opt_nodiscard, EXT4_MOUNT_DISCARD, MOPT_CLEAR},
1513         {Opt_delalloc, EXT4_MOUNT_DELALLOC,
1514          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1515         {Opt_nodelalloc, EXT4_MOUNT_DELALLOC,
1516          MOPT_EXT4_ONLY | MOPT_CLEAR},
1517         {Opt_nojournal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1518          MOPT_EXT4_ONLY | MOPT_CLEAR},
1519         {Opt_journal_checksum, EXT4_MOUNT_JOURNAL_CHECKSUM,
1520          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1521         {Opt_journal_async_commit, (EXT4_MOUNT_JOURNAL_ASYNC_COMMIT |
1522                                     EXT4_MOUNT_JOURNAL_CHECKSUM),
1523          MOPT_EXT4_ONLY | MOPT_SET | MOPT_EXPLICIT},
1524         {Opt_noload, EXT4_MOUNT_NOLOAD, MOPT_NO_EXT2 | MOPT_SET},
1525         {Opt_err_panic, EXT4_MOUNT_ERRORS_PANIC, MOPT_SET | MOPT_CLEAR_ERR},
1526         {Opt_err_ro, EXT4_MOUNT_ERRORS_RO, MOPT_SET | MOPT_CLEAR_ERR},
1527         {Opt_err_cont, EXT4_MOUNT_ERRORS_CONT, MOPT_SET | MOPT_CLEAR_ERR},
1528         {Opt_data_err_abort, EXT4_MOUNT_DATA_ERR_ABORT,
1529          MOPT_NO_EXT2},
1530         {Opt_data_err_ignore, EXT4_MOUNT_DATA_ERR_ABORT,
1531          MOPT_NO_EXT2},
1532         {Opt_barrier, EXT4_MOUNT_BARRIER, MOPT_SET},
1533         {Opt_nobarrier, EXT4_MOUNT_BARRIER, MOPT_CLEAR},
1534         {Opt_noauto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_SET},
1535         {Opt_auto_da_alloc, EXT4_MOUNT_NO_AUTO_DA_ALLOC, MOPT_CLEAR},
1536         {Opt_noinit_itable, EXT4_MOUNT_INIT_INODE_TABLE, MOPT_CLEAR},
1537         {Opt_commit, 0, MOPT_GTE0},
1538         {Opt_max_batch_time, 0, MOPT_GTE0},
1539         {Opt_min_batch_time, 0, MOPT_GTE0},
1540         {Opt_inode_readahead_blks, 0, MOPT_GTE0},
1541         {Opt_init_itable, 0, MOPT_GTE0},
1542         {Opt_dax, EXT4_MOUNT_DAX, MOPT_SET},
1543         {Opt_stripe, 0, MOPT_GTE0},
1544         {Opt_resuid, 0, MOPT_GTE0},
1545         {Opt_resgid, 0, MOPT_GTE0},
1546         {Opt_journal_dev, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1547         {Opt_journal_path, 0, MOPT_NO_EXT2 | MOPT_STRING},
1548         {Opt_journal_ioprio, 0, MOPT_NO_EXT2 | MOPT_GTE0},
1549         {Opt_data_journal, EXT4_MOUNT_JOURNAL_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1550         {Opt_data_ordered, EXT4_MOUNT_ORDERED_DATA, MOPT_NO_EXT2 | MOPT_DATAJ},
1551         {Opt_data_writeback, EXT4_MOUNT_WRITEBACK_DATA,
1552          MOPT_NO_EXT2 | MOPT_DATAJ},
1553         {Opt_user_xattr, EXT4_MOUNT_XATTR_USER, MOPT_SET},
1554         {Opt_nouser_xattr, EXT4_MOUNT_XATTR_USER, MOPT_CLEAR},
1555 #ifdef CONFIG_EXT4_FS_POSIX_ACL
1556         {Opt_acl, EXT4_MOUNT_POSIX_ACL, MOPT_SET},
1557         {Opt_noacl, EXT4_MOUNT_POSIX_ACL, MOPT_CLEAR},
1558 #else
1559         {Opt_acl, 0, MOPT_NOSUPPORT},
1560         {Opt_noacl, 0, MOPT_NOSUPPORT},
1561 #endif
1562         {Opt_nouid32, EXT4_MOUNT_NO_UID32, MOPT_SET},
1563         {Opt_debug, EXT4_MOUNT_DEBUG, MOPT_SET},
1564         {Opt_quota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA, MOPT_SET | MOPT_Q},
1565         {Opt_usrquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA,
1566                                                         MOPT_SET | MOPT_Q},
1567         {Opt_grpquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_GRPQUOTA,
1568                                                         MOPT_SET | MOPT_Q},
1569         {Opt_prjquota, EXT4_MOUNT_QUOTA | EXT4_MOUNT_PRJQUOTA,
1570                                                         MOPT_SET | MOPT_Q},
1571         {Opt_noquota, (EXT4_MOUNT_QUOTA | EXT4_MOUNT_USRQUOTA |
1572                        EXT4_MOUNT_GRPQUOTA | EXT4_MOUNT_PRJQUOTA),
1573                                                         MOPT_CLEAR | MOPT_Q},
1574         {Opt_usrjquota, 0, MOPT_Q | MOPT_STRING},
1575         {Opt_grpjquota, 0, MOPT_Q | MOPT_STRING},
1576         {Opt_offusrjquota, 0, MOPT_Q},
1577         {Opt_offgrpjquota, 0, MOPT_Q},
1578         {Opt_jqfmt_vfsold, QFMT_VFS_OLD, MOPT_QFMT},
1579         {Opt_jqfmt_vfsv0, QFMT_VFS_V0, MOPT_QFMT},
1580         {Opt_jqfmt_vfsv1, QFMT_VFS_V1, MOPT_QFMT},
1581         {Opt_max_dir_size_kb, 0, MOPT_GTE0},
1582         {Opt_test_dummy_encryption, 0, MOPT_GTE0},
1583         {Opt_err, 0, 0}
1584 };
1585
1586 static int handle_mount_opt(struct super_block *sb, char *opt, int token,
1587                             substring_t *args, unsigned long *journal_devnum,
1588                             unsigned int *journal_ioprio, int is_remount)
1589 {
1590         struct ext4_sb_info *sbi = EXT4_SB(sb);
1591         const struct mount_opts *m;
1592         kuid_t uid;
1593         kgid_t gid;
1594         int arg = 0;
1595
1596 #ifdef CONFIG_QUOTA
1597         if (token == Opt_usrjquota)
1598                 return set_qf_name(sb, USRQUOTA, &args[0]);
1599         else if (token == Opt_grpjquota)
1600                 return set_qf_name(sb, GRPQUOTA, &args[0]);
1601         else if (token == Opt_offusrjquota)
1602                 return clear_qf_name(sb, USRQUOTA);
1603         else if (token == Opt_offgrpjquota)
1604                 return clear_qf_name(sb, GRPQUOTA);
1605 #endif
1606         switch (token) {
1607         case Opt_noacl:
1608         case Opt_nouser_xattr:
1609                 ext4_msg(sb, KERN_WARNING, deprecated_msg, opt, "3.5");
1610                 break;
1611         case Opt_sb:
1612                 return 1;       /* handled by get_sb_block() */
1613         case Opt_removed:
1614                 ext4_msg(sb, KERN_WARNING, "Ignoring removed %s option", opt);
1615                 return 1;
1616         case Opt_abort:
1617                 sbi->s_mount_flags |= EXT4_MF_FS_ABORTED;
1618                 return 1;
1619         case Opt_i_version:
1620                 sb->s_flags |= MS_I_VERSION;
1621                 return 1;
1622         case Opt_lazytime:
1623                 sb->s_flags |= MS_LAZYTIME;
1624                 return 1;
1625         case Opt_nolazytime:
1626                 sb->s_flags &= ~MS_LAZYTIME;
1627                 return 1;
1628         }
1629
1630         for (m = ext4_mount_opts; m->token != Opt_err; m++)
1631                 if (token == m->token)
1632                         break;
1633
1634         if (m->token == Opt_err) {
1635                 ext4_msg(sb, KERN_ERR, "Unrecognized mount option \"%s\" "
1636                          "or missing value", opt);
1637                 return -1;
1638         }
1639
1640         if ((m->flags & MOPT_NO_EXT2) && IS_EXT2_SB(sb)) {
1641                 ext4_msg(sb, KERN_ERR,
1642                          "Mount option \"%s\" incompatible with ext2", opt);
1643                 return -1;
1644         }
1645         if ((m->flags & MOPT_NO_EXT3) && IS_EXT3_SB(sb)) {
1646                 ext4_msg(sb, KERN_ERR,
1647                          "Mount option \"%s\" incompatible with ext3", opt);
1648                 return -1;
1649         }
1650
1651         if (args->from && !(m->flags & MOPT_STRING) && match_int(args, &arg))
1652                 return -1;
1653         if (args->from && (m->flags & MOPT_GTE0) && (arg < 0))
1654                 return -1;
1655         if (m->flags & MOPT_EXPLICIT) {
1656                 if (m->mount_opt & EXT4_MOUNT_DELALLOC) {
1657                         set_opt2(sb, EXPLICIT_DELALLOC);
1658                 } else if (m->mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) {
1659                         set_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM);
1660                 } else
1661                         return -1;
1662         }
1663         if (m->flags & MOPT_CLEAR_ERR)
1664                 clear_opt(sb, ERRORS_MASK);
1665         if (token == Opt_noquota && sb_any_quota_loaded(sb)) {
1666                 ext4_msg(sb, KERN_ERR, "Cannot change quota "
1667                          "options when quota turned on");
1668                 return -1;
1669         }
1670
1671         if (m->flags & MOPT_NOSUPPORT) {
1672                 ext4_msg(sb, KERN_ERR, "%s option not supported", opt);
1673         } else if (token == Opt_commit) {
1674                 if (arg == 0)
1675                         arg = JBD2_DEFAULT_MAX_COMMIT_AGE;
1676                 sbi->s_commit_interval = HZ * arg;
1677         } else if (token == Opt_max_batch_time) {
1678                 sbi->s_max_batch_time = arg;
1679         } else if (token == Opt_min_batch_time) {
1680                 sbi->s_min_batch_time = arg;
1681         } else if (token == Opt_inode_readahead_blks) {
1682                 if (arg && (arg > (1 << 30) || !is_power_of_2(arg))) {
1683                         ext4_msg(sb, KERN_ERR,
1684                                  "EXT4-fs: inode_readahead_blks must be "
1685                                  "0 or a power of 2 smaller than 2^31");
1686                         return -1;
1687                 }
1688                 sbi->s_inode_readahead_blks = arg;
1689         } else if (token == Opt_init_itable) {
1690                 set_opt(sb, INIT_INODE_TABLE);
1691                 if (!args->from)
1692                         arg = EXT4_DEF_LI_WAIT_MULT;
1693                 sbi->s_li_wait_mult = arg;
1694         } else if (token == Opt_max_dir_size_kb) {
1695                 sbi->s_max_dir_size_kb = arg;
1696         } else if (token == Opt_stripe) {
1697                 sbi->s_stripe = arg;
1698         } else if (token == Opt_resuid) {
1699                 uid = make_kuid(current_user_ns(), arg);
1700                 if (!uid_valid(uid)) {
1701                         ext4_msg(sb, KERN_ERR, "Invalid uid value %d", arg);
1702                         return -1;
1703                 }
1704                 sbi->s_resuid = uid;
1705         } else if (token == Opt_resgid) {
1706                 gid = make_kgid(current_user_ns(), arg);
1707                 if (!gid_valid(gid)) {
1708                         ext4_msg(sb, KERN_ERR, "Invalid gid value %d", arg);
1709                         return -1;
1710                 }
1711                 sbi->s_resgid = gid;
1712         } else if (token == Opt_journal_dev) {
1713                 if (is_remount) {
1714                         ext4_msg(sb, KERN_ERR,
1715                                  "Cannot specify journal on remount");
1716                         return -1;
1717                 }
1718                 *journal_devnum = arg;
1719         } else if (token == Opt_journal_path) {
1720                 char *journal_path;
1721                 struct inode *journal_inode;
1722                 struct path path;
1723                 int error;
1724
1725                 if (is_remount) {
1726                         ext4_msg(sb, KERN_ERR,
1727                                  "Cannot specify journal on remount");
1728                         return -1;
1729                 }
1730                 journal_path = match_strdup(&args[0]);
1731                 if (!journal_path) {
1732                         ext4_msg(sb, KERN_ERR, "error: could not dup "
1733                                 "journal device string");
1734                         return -1;
1735                 }
1736
1737                 error = kern_path(journal_path, LOOKUP_FOLLOW, &path);
1738                 if (error) {
1739                         ext4_msg(sb, KERN_ERR, "error: could not find "
1740                                 "journal device path: error %d", error);
1741                         kfree(journal_path);
1742                         return -1;
1743                 }
1744
1745                 journal_inode = d_inode(path.dentry);
1746                 if (!S_ISBLK(journal_inode->i_mode)) {
1747                         ext4_msg(sb, KERN_ERR, "error: journal path %s "
1748                                 "is not a block device", journal_path);
1749                         path_put(&path);
1750                         kfree(journal_path);
1751                         return -1;
1752                 }
1753
1754                 *journal_devnum = new_encode_dev(journal_inode->i_rdev);
1755                 path_put(&path);
1756                 kfree(journal_path);
1757         } else if (token == Opt_journal_ioprio) {
1758                 if (arg > 7) {
1759                         ext4_msg(sb, KERN_ERR, "Invalid journal IO priority"
1760                                  " (must be 0-7)");
1761                         return -1;
1762                 }
1763                 *journal_ioprio =
1764                         IOPRIO_PRIO_VALUE(IOPRIO_CLASS_BE, arg);
1765         } else if (token == Opt_test_dummy_encryption) {
1766 #ifdef CONFIG_EXT4_FS_ENCRYPTION
1767                 sbi->s_mount_flags |= EXT4_MF_TEST_DUMMY_ENCRYPTION;
1768                 ext4_msg(sb, KERN_WARNING,
1769                          "Test dummy encryption mode enabled");
1770 #else
1771                 ext4_msg(sb, KERN_WARNING,
1772                          "Test dummy encryption mount option ignored");
1773 #endif
1774         } else if (m->flags & MOPT_DATAJ) {
1775                 if (is_remount) {
1776                         if (!sbi->s_journal)
1777                                 ext4_msg(sb, KERN_WARNING, "Remounting file system with no journal so ignoring journalled data option");
1778                         else if (test_opt(sb, DATA_FLAGS) != m->mount_opt) {
1779                                 ext4_msg(sb, KERN_ERR,
1780                                          "Cannot change data mode on remount");
1781                                 return -1;
1782                         }
1783                 } else {
1784                         clear_opt(sb, DATA_FLAGS);
1785                         sbi->s_mount_opt |= m->mount_opt;
1786                 }
1787 #ifdef CONFIG_QUOTA
1788         } else if (m->flags & MOPT_QFMT) {
1789                 if (sb_any_quota_loaded(sb) &&
1790                     sbi->s_jquota_fmt != m->mount_opt) {
1791                         ext4_msg(sb, KERN_ERR, "Cannot change journaled "
1792                                  "quota options when quota turned on");
1793                         return -1;
1794                 }
1795                 if (ext4_has_feature_quota(sb)) {
1796                         ext4_msg(sb, KERN_INFO,
1797                                  "Quota format mount options ignored "
1798                                  "when QUOTA feature is enabled");
1799                         return 1;
1800                 }
1801                 sbi->s_jquota_fmt = m->mount_opt;
1802 #endif
1803         } else if (token == Opt_dax) {
1804 #ifdef CONFIG_FS_DAX
1805                 ext4_msg(sb, KERN_WARNING,
1806                 "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
1807                         sbi->s_mount_opt |= m->mount_opt;
1808 #else
1809                 ext4_msg(sb, KERN_INFO, "dax option not supported");
1810                 return -1;
1811 #endif
1812         } else if (token == Opt_data_err_abort) {
1813                 sbi->s_mount_opt |= m->mount_opt;
1814         } else if (token == Opt_data_err_ignore) {
1815                 sbi->s_mount_opt &= ~m->mount_opt;
1816         } else {
1817                 if (!args->from)
1818                         arg = 1;
1819                 if (m->flags & MOPT_CLEAR)
1820                         arg = !arg;
1821                 else if (unlikely(!(m->flags & MOPT_SET))) {
1822                         ext4_msg(sb, KERN_WARNING,
1823                                  "buggy handling of option %s", opt);
1824                         WARN_ON(1);
1825                         return -1;
1826                 }
1827                 if (arg != 0)
1828                         sbi->s_mount_opt |= m->mount_opt;
1829                 else
1830                         sbi->s_mount_opt &= ~m->mount_opt;
1831         }
1832         return 1;
1833 }
1834
1835 static int parse_options(char *options, struct super_block *sb,
1836                          unsigned long *journal_devnum,
1837                          unsigned int *journal_ioprio,
1838                          int is_remount)
1839 {
1840         struct ext4_sb_info *sbi = EXT4_SB(sb);
1841         char *p;
1842         substring_t args[MAX_OPT_ARGS];
1843         int token;
1844
1845         if (!options)
1846                 return 1;
1847
1848         while ((p = strsep(&options, ",")) != NULL) {
1849                 if (!*p)
1850                         continue;
1851                 /*
1852                  * Initialize args struct so we know whether arg was
1853                  * found; some options take optional arguments.
1854                  */
1855                 args[0].to = args[0].from = NULL;
1856                 token = match_token(p, tokens, args);
1857                 if (handle_mount_opt(sb, p, token, args, journal_devnum,
1858                                      journal_ioprio, is_remount) < 0)
1859                         return 0;
1860         }
1861 #ifdef CONFIG_QUOTA
1862         /*
1863          * We do the test below only for project quotas. 'usrquota' and
1864          * 'grpquota' mount options are allowed even without quota feature
1865          * to support legacy quotas in quota files.
1866          */
1867         if (test_opt(sb, PRJQUOTA) && !ext4_has_feature_project(sb)) {
1868                 ext4_msg(sb, KERN_ERR, "Project quota feature not enabled. "
1869                          "Cannot enable project quota enforcement.");
1870                 return 0;
1871         }
1872         if (sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
1873                 if (test_opt(sb, USRQUOTA) && sbi->s_qf_names[USRQUOTA])
1874                         clear_opt(sb, USRQUOTA);
1875
1876                 if (test_opt(sb, GRPQUOTA) && sbi->s_qf_names[GRPQUOTA])
1877                         clear_opt(sb, GRPQUOTA);
1878
1879                 if (test_opt(sb, GRPQUOTA) || test_opt(sb, USRQUOTA)) {
1880                         ext4_msg(sb, KERN_ERR, "old and new quota "
1881                                         "format mixing");
1882                         return 0;
1883                 }
1884
1885                 if (!sbi->s_jquota_fmt) {
1886                         ext4_msg(sb, KERN_ERR, "journaled quota format "
1887                                         "not specified");
1888                         return 0;
1889                 }
1890         }
1891 #endif
1892         if (test_opt(sb, DIOREAD_NOLOCK)) {
1893                 int blocksize =
1894                         BLOCK_SIZE << le32_to_cpu(sbi->s_es->s_log_block_size);
1895
1896                 if (blocksize < PAGE_SIZE) {
1897                         ext4_msg(sb, KERN_ERR, "can't mount with "
1898                                  "dioread_nolock if block size != PAGE_SIZE");
1899                         return 0;
1900                 }
1901         }
1902         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA &&
1903             test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
1904                 ext4_msg(sb, KERN_ERR, "can't mount with journal_async_commit "
1905                          "in data=ordered mode");
1906                 return 0;
1907         }
1908         return 1;
1909 }
1910
1911 static inline void ext4_show_quota_options(struct seq_file *seq,
1912                                            struct super_block *sb)
1913 {
1914 #if defined(CONFIG_QUOTA)
1915         struct ext4_sb_info *sbi = EXT4_SB(sb);
1916
1917         if (sbi->s_jquota_fmt) {
1918                 char *fmtname = "";
1919
1920                 switch (sbi->s_jquota_fmt) {
1921                 case QFMT_VFS_OLD:
1922                         fmtname = "vfsold";
1923                         break;
1924                 case QFMT_VFS_V0:
1925                         fmtname = "vfsv0";
1926                         break;
1927                 case QFMT_VFS_V1:
1928                         fmtname = "vfsv1";
1929                         break;
1930                 }
1931                 seq_printf(seq, ",jqfmt=%s", fmtname);
1932         }
1933
1934         if (sbi->s_qf_names[USRQUOTA])
1935                 seq_show_option(seq, "usrjquota", sbi->s_qf_names[USRQUOTA]);
1936
1937         if (sbi->s_qf_names[GRPQUOTA])
1938                 seq_show_option(seq, "grpjquota", sbi->s_qf_names[GRPQUOTA]);
1939 #endif
1940 }
1941
1942 static const char *token2str(int token)
1943 {
1944         const struct match_token *t;
1945
1946         for (t = tokens; t->token != Opt_err; t++)
1947                 if (t->token == token && !strchr(t->pattern, '='))
1948                         break;
1949         return t->pattern;
1950 }
1951
1952 /*
1953  * Show an option if
1954  *  - it's set to a non-default value OR
1955  *  - if the per-sb default is different from the global default
1956  */
1957 static int _ext4_show_options(struct seq_file *seq, struct super_block *sb,
1958                               int nodefs)
1959 {
1960         struct ext4_sb_info *sbi = EXT4_SB(sb);
1961         struct ext4_super_block *es = sbi->s_es;
1962         int def_errors, def_mount_opt = nodefs ? 0 : sbi->s_def_mount_opt;
1963         const struct mount_opts *m;
1964         char sep = nodefs ? '\n' : ',';
1965
1966 #define SEQ_OPTS_PUTS(str) seq_printf(seq, "%c" str, sep)
1967 #define SEQ_OPTS_PRINT(str, arg) seq_printf(seq, "%c" str, sep, arg)
1968
1969         if (sbi->s_sb_block != 1)
1970                 SEQ_OPTS_PRINT("sb=%llu", sbi->s_sb_block);
1971
1972         for (m = ext4_mount_opts; m->token != Opt_err; m++) {
1973                 int want_set = m->flags & MOPT_SET;
1974                 if (((m->flags & (MOPT_SET|MOPT_CLEAR)) == 0) ||
1975                     (m->flags & MOPT_CLEAR_ERR))
1976                         continue;
1977                 if (!(m->mount_opt & (sbi->s_mount_opt ^ def_mount_opt)))
1978                         continue; /* skip if same as the default */
1979                 if ((want_set &&
1980                      (sbi->s_mount_opt & m->mount_opt) != m->mount_opt) ||
1981                     (!want_set && (sbi->s_mount_opt & m->mount_opt)))
1982                         continue; /* select Opt_noFoo vs Opt_Foo */
1983                 SEQ_OPTS_PRINT("%s", token2str(m->token));
1984         }
1985
1986         if (nodefs || !uid_eq(sbi->s_resuid, make_kuid(&init_user_ns, EXT4_DEF_RESUID)) ||
1987             le16_to_cpu(es->s_def_resuid) != EXT4_DEF_RESUID)
1988                 SEQ_OPTS_PRINT("resuid=%u",
1989                                 from_kuid_munged(&init_user_ns, sbi->s_resuid));
1990         if (nodefs || !gid_eq(sbi->s_resgid, make_kgid(&init_user_ns, EXT4_DEF_RESGID)) ||
1991             le16_to_cpu(es->s_def_resgid) != EXT4_DEF_RESGID)
1992                 SEQ_OPTS_PRINT("resgid=%u",
1993                                 from_kgid_munged(&init_user_ns, sbi->s_resgid));
1994         def_errors = nodefs ? -1 : le16_to_cpu(es->s_errors);
1995         if (test_opt(sb, ERRORS_RO) && def_errors != EXT4_ERRORS_RO)
1996                 SEQ_OPTS_PUTS("errors=remount-ro");
1997         if (test_opt(sb, ERRORS_CONT) && def_errors != EXT4_ERRORS_CONTINUE)
1998                 SEQ_OPTS_PUTS("errors=continue");
1999         if (test_opt(sb, ERRORS_PANIC) && def_errors != EXT4_ERRORS_PANIC)
2000                 SEQ_OPTS_PUTS("errors=panic");
2001         if (nodefs || sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ)
2002                 SEQ_OPTS_PRINT("commit=%lu", sbi->s_commit_interval / HZ);
2003         if (nodefs || sbi->s_min_batch_time != EXT4_DEF_MIN_BATCH_TIME)
2004                 SEQ_OPTS_PRINT("min_batch_time=%u", sbi->s_min_batch_time);
2005         if (nodefs || sbi->s_max_batch_time != EXT4_DEF_MAX_BATCH_TIME)
2006                 SEQ_OPTS_PRINT("max_batch_time=%u", sbi->s_max_batch_time);
2007         if (sb->s_flags & MS_I_VERSION)
2008                 SEQ_OPTS_PUTS("i_version");
2009         if (nodefs || sbi->s_stripe)
2010                 SEQ_OPTS_PRINT("stripe=%lu", sbi->s_stripe);
2011         if (EXT4_MOUNT_DATA_FLAGS & (sbi->s_mount_opt ^ def_mount_opt)) {
2012                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
2013                         SEQ_OPTS_PUTS("data=journal");
2014                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
2015                         SEQ_OPTS_PUTS("data=ordered");
2016                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_WRITEBACK_DATA)
2017                         SEQ_OPTS_PUTS("data=writeback");
2018         }
2019         if (nodefs ||
2020             sbi->s_inode_readahead_blks != EXT4_DEF_INODE_READAHEAD_BLKS)
2021                 SEQ_OPTS_PRINT("inode_readahead_blks=%u",
2022                                sbi->s_inode_readahead_blks);
2023
2024         if (nodefs || (test_opt(sb, INIT_INODE_TABLE) &&
2025                        (sbi->s_li_wait_mult != EXT4_DEF_LI_WAIT_MULT)))
2026                 SEQ_OPTS_PRINT("init_itable=%u", sbi->s_li_wait_mult);
2027         if (nodefs || sbi->s_max_dir_size_kb)
2028                 SEQ_OPTS_PRINT("max_dir_size_kb=%u", sbi->s_max_dir_size_kb);
2029         if (test_opt(sb, DATA_ERR_ABORT))
2030                 SEQ_OPTS_PUTS("data_err=abort");
2031         if (DUMMY_ENCRYPTION_ENABLED(sbi))
2032                 SEQ_OPTS_PUTS("test_dummy_encryption");
2033
2034         ext4_show_quota_options(seq, sb);
2035         return 0;
2036 }
2037
2038 static int ext4_show_options(struct seq_file *seq, struct dentry *root)
2039 {
2040         return _ext4_show_options(seq, root->d_sb, 0);
2041 }
2042
2043 int ext4_seq_options_show(struct seq_file *seq, void *offset)
2044 {
2045         struct super_block *sb = seq->private;
2046         int rc;
2047
2048         seq_puts(seq, (sb->s_flags & MS_RDONLY) ? "ro" : "rw");
2049         rc = _ext4_show_options(seq, sb, 1);
2050         seq_puts(seq, "\n");
2051         return rc;
2052 }
2053
2054 static int ext4_setup_super(struct super_block *sb, struct ext4_super_block *es,
2055                             int read_only)
2056 {
2057         struct ext4_sb_info *sbi = EXT4_SB(sb);
2058         int res = 0;
2059
2060         if (le32_to_cpu(es->s_rev_level) > EXT4_MAX_SUPP_REV) {
2061                 ext4_msg(sb, KERN_ERR, "revision level too high, "
2062                          "forcing read-only mode");
2063                 res = MS_RDONLY;
2064         }
2065         if (read_only)
2066                 goto done;
2067         if (!(sbi->s_mount_state & EXT4_VALID_FS))
2068                 ext4_msg(sb, KERN_WARNING, "warning: mounting unchecked fs, "
2069                          "running e2fsck is recommended");
2070         else if (sbi->s_mount_state & EXT4_ERROR_FS)
2071                 ext4_msg(sb, KERN_WARNING,
2072                          "warning: mounting fs with errors, "
2073                          "running e2fsck is recommended");
2074         else if ((__s16) le16_to_cpu(es->s_max_mnt_count) > 0 &&
2075                  le16_to_cpu(es->s_mnt_count) >=
2076                  (unsigned short) (__s16) le16_to_cpu(es->s_max_mnt_count))
2077                 ext4_msg(sb, KERN_WARNING,
2078                          "warning: maximal mount count reached, "
2079                          "running e2fsck is recommended");
2080         else if (le32_to_cpu(es->s_checkinterval) &&
2081                 (le32_to_cpu(es->s_lastcheck) +
2082                         le32_to_cpu(es->s_checkinterval) <= get_seconds()))
2083                 ext4_msg(sb, KERN_WARNING,
2084                          "warning: checktime reached, "
2085                          "running e2fsck is recommended");
2086         if (!sbi->s_journal)
2087                 es->s_state &= cpu_to_le16(~EXT4_VALID_FS);
2088         if (!(__s16) le16_to_cpu(es->s_max_mnt_count))
2089                 es->s_max_mnt_count = cpu_to_le16(EXT4_DFL_MAX_MNT_COUNT);
2090         le16_add_cpu(&es->s_mnt_count, 1);
2091         es->s_mtime = cpu_to_le32(get_seconds());
2092         ext4_update_dynamic_rev(sb);
2093         if (sbi->s_journal)
2094                 ext4_set_feature_journal_needs_recovery(sb);
2095
2096         ext4_commit_super(sb, 1);
2097 done:
2098         if (test_opt(sb, DEBUG))
2099                 printk(KERN_INFO "[EXT4 FS bs=%lu, gc=%u, "
2100                                 "bpg=%lu, ipg=%lu, mo=%04x, mo2=%04x]\n",
2101                         sb->s_blocksize,
2102                         sbi->s_groups_count,
2103                         EXT4_BLOCKS_PER_GROUP(sb),
2104                         EXT4_INODES_PER_GROUP(sb),
2105                         sbi->s_mount_opt, sbi->s_mount_opt2);
2106
2107         cleancache_init_fs(sb);
2108         return res;
2109 }
2110
2111 int ext4_alloc_flex_bg_array(struct super_block *sb, ext4_group_t ngroup)
2112 {
2113         struct ext4_sb_info *sbi = EXT4_SB(sb);
2114         struct flex_groups **old_groups, **new_groups;
2115         int size, i, j;
2116
2117         if (!sbi->s_log_groups_per_flex)
2118                 return 0;
2119
2120         size = ext4_flex_group(sbi, ngroup - 1) + 1;
2121         if (size <= sbi->s_flex_groups_allocated)
2122                 return 0;
2123
2124         new_groups = ext4_kvzalloc(roundup_pow_of_two(size *
2125                                    sizeof(*sbi->s_flex_groups)), GFP_KERNEL);
2126         if (!new_groups) {
2127                 ext4_msg(sb, KERN_ERR,
2128                          "not enough memory for %d flex group pointers", size);
2129                 return -ENOMEM;
2130         }
2131         for (i = sbi->s_flex_groups_allocated; i < size; i++) {
2132                 new_groups[i] = ext4_kvzalloc(roundup_pow_of_two(
2133                                               sizeof(struct flex_groups)),
2134                                               GFP_KERNEL);
2135                 if (!new_groups[i]) {
2136                         for (j = sbi->s_flex_groups_allocated; j < i; j++)
2137                                 kvfree(new_groups[j]);
2138                         kvfree(new_groups);
2139                         ext4_msg(sb, KERN_ERR,
2140                                  "not enough memory for %d flex groups", size);
2141                         return -ENOMEM;
2142                 }
2143         }
2144         rcu_read_lock();
2145         old_groups = rcu_dereference(sbi->s_flex_groups);
2146         if (old_groups)
2147                 memcpy(new_groups, old_groups,
2148                        (sbi->s_flex_groups_allocated *
2149                         sizeof(struct flex_groups *)));
2150         rcu_read_unlock();
2151         rcu_assign_pointer(sbi->s_flex_groups, new_groups);
2152         sbi->s_flex_groups_allocated = size;
2153         if (old_groups)
2154                 ext4_kvfree_array_rcu(old_groups);
2155         return 0;
2156 }
2157
2158 static int ext4_fill_flex_info(struct super_block *sb)
2159 {
2160         struct ext4_sb_info *sbi = EXT4_SB(sb);
2161         struct ext4_group_desc *gdp = NULL;
2162         struct flex_groups *fg;
2163         ext4_group_t flex_group;
2164         int i, err;
2165
2166         sbi->s_log_groups_per_flex = sbi->s_es->s_log_groups_per_flex;
2167         if (sbi->s_log_groups_per_flex < 1 || sbi->s_log_groups_per_flex > 31) {
2168                 sbi->s_log_groups_per_flex = 0;
2169                 return 1;
2170         }
2171
2172         err = ext4_alloc_flex_bg_array(sb, sbi->s_groups_count);
2173         if (err)
2174                 goto failed;
2175
2176         for (i = 0; i < sbi->s_groups_count; i++) {
2177                 gdp = ext4_get_group_desc(sb, i, NULL);
2178
2179                 flex_group = ext4_flex_group(sbi, i);
2180                 fg = sbi_array_rcu_deref(sbi, s_flex_groups, flex_group);
2181                 atomic_add(ext4_free_inodes_count(sb, gdp), &fg->free_inodes);
2182                 atomic64_add(ext4_free_group_clusters(sb, gdp),
2183                              &fg->free_clusters);
2184                 atomic_add(ext4_used_dirs_count(sb, gdp), &fg->used_dirs);
2185         }
2186
2187         return 1;
2188 failed:
2189         return 0;
2190 }
2191
2192 static __le16 ext4_group_desc_csum(struct super_block *sb, __u32 block_group,
2193                                    struct ext4_group_desc *gdp)
2194 {
2195         int offset = offsetof(struct ext4_group_desc, bg_checksum);
2196         __u16 crc = 0;
2197         __le32 le_group = cpu_to_le32(block_group);
2198         struct ext4_sb_info *sbi = EXT4_SB(sb);
2199
2200         if (ext4_has_metadata_csum(sbi->s_sb)) {
2201                 /* Use new metadata_csum algorithm */
2202                 __u32 csum32;
2203                 __u16 dummy_csum = 0;
2204
2205                 csum32 = ext4_chksum(sbi, sbi->s_csum_seed, (__u8 *)&le_group,
2206                                      sizeof(le_group));
2207                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp, offset);
2208                 csum32 = ext4_chksum(sbi, csum32, (__u8 *)&dummy_csum,
2209                                      sizeof(dummy_csum));
2210                 offset += sizeof(dummy_csum);
2211                 if (offset < sbi->s_desc_size)
2212                         csum32 = ext4_chksum(sbi, csum32, (__u8 *)gdp + offset,
2213                                              sbi->s_desc_size - offset);
2214
2215                 crc = csum32 & 0xFFFF;
2216                 goto out;
2217         }
2218
2219         /* old crc16 code */
2220         if (!ext4_has_feature_gdt_csum(sb))
2221                 return 0;
2222
2223         crc = crc16(~0, sbi->s_es->s_uuid, sizeof(sbi->s_es->s_uuid));
2224         crc = crc16(crc, (__u8 *)&le_group, sizeof(le_group));
2225         crc = crc16(crc, (__u8 *)gdp, offset);
2226         offset += sizeof(gdp->bg_checksum); /* skip checksum */
2227         /* for checksum of struct ext4_group_desc do the rest...*/
2228         if (ext4_has_feature_64bit(sb) &&
2229             offset < le16_to_cpu(sbi->s_es->s_desc_size))
2230                 crc = crc16(crc, (__u8 *)gdp + offset,
2231                             le16_to_cpu(sbi->s_es->s_desc_size) -
2232                                 offset);
2233
2234 out:
2235         return cpu_to_le16(crc);
2236 }
2237
2238 int ext4_group_desc_csum_verify(struct super_block *sb, __u32 block_group,
2239                                 struct ext4_group_desc *gdp)
2240 {
2241         if (ext4_has_group_desc_csum(sb) &&
2242             (gdp->bg_checksum != ext4_group_desc_csum(sb, block_group, gdp)))
2243                 return 0;
2244
2245         return 1;
2246 }
2247
2248 void ext4_group_desc_csum_set(struct super_block *sb, __u32 block_group,
2249                               struct ext4_group_desc *gdp)
2250 {
2251         if (!ext4_has_group_desc_csum(sb))
2252                 return;
2253         gdp->bg_checksum = ext4_group_desc_csum(sb, block_group, gdp);
2254 }
2255
2256 /* Called at mount-time, super-block is locked */
2257 static int ext4_check_descriptors(struct super_block *sb,
2258                                   ext4_fsblk_t sb_block,
2259                                   ext4_group_t *first_not_zeroed)
2260 {
2261         struct ext4_sb_info *sbi = EXT4_SB(sb);
2262         ext4_fsblk_t first_block = le32_to_cpu(sbi->s_es->s_first_data_block);
2263         ext4_fsblk_t last_block;
2264         ext4_fsblk_t last_bg_block = sb_block + ext4_bg_num_gdb(sb, 0);
2265         ext4_fsblk_t block_bitmap;
2266         ext4_fsblk_t inode_bitmap;
2267         ext4_fsblk_t inode_table;
2268         int flexbg_flag = 0;
2269         ext4_group_t i, grp = sbi->s_groups_count;
2270
2271         if (ext4_has_feature_flex_bg(sb))
2272                 flexbg_flag = 1;
2273
2274         ext4_debug("Checking group descriptors");
2275
2276         for (i = 0; i < sbi->s_groups_count; i++) {
2277                 struct ext4_group_desc *gdp = ext4_get_group_desc(sb, i, NULL);
2278
2279                 if (i == sbi->s_groups_count - 1 || flexbg_flag)
2280                         last_block = ext4_blocks_count(sbi->s_es) - 1;
2281                 else
2282                         last_block = first_block +
2283                                 (EXT4_BLOCKS_PER_GROUP(sb) - 1);
2284
2285                 if ((grp == sbi->s_groups_count) &&
2286                    !(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2287                         grp = i;
2288
2289                 block_bitmap = ext4_block_bitmap(sb, gdp);
2290                 if (block_bitmap == sb_block) {
2291                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2292                                  "Block bitmap for group %u overlaps "
2293                                  "superblock", i);
2294                         if (!(sb->s_flags & MS_RDONLY))
2295                                 return 0;
2296                 }
2297                 if (block_bitmap >= sb_block + 1 &&
2298                     block_bitmap <= last_bg_block) {
2299                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2300                                  "Block bitmap for group %u overlaps "
2301                                  "block group descriptors", i);
2302                         if (!(sb->s_flags & MS_RDONLY))
2303                                 return 0;
2304                 }
2305                 if (block_bitmap < first_block || block_bitmap > last_block) {
2306                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2307                                "Block bitmap for group %u not in group "
2308                                "(block %llu)!", i, block_bitmap);
2309                         return 0;
2310                 }
2311                 inode_bitmap = ext4_inode_bitmap(sb, gdp);
2312                 if (inode_bitmap == sb_block) {
2313                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2314                                  "Inode bitmap for group %u overlaps "
2315                                  "superblock", i);
2316                         if (!(sb->s_flags & MS_RDONLY))
2317                                 return 0;
2318                 }
2319                 if (inode_bitmap >= sb_block + 1 &&
2320                     inode_bitmap <= last_bg_block) {
2321                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2322                                  "Inode bitmap for group %u overlaps "
2323                                  "block group descriptors", i);
2324                         if (!(sb->s_flags & MS_RDONLY))
2325                                 return 0;
2326                 }
2327                 if (inode_bitmap < first_block || inode_bitmap > last_block) {
2328                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2329                                "Inode bitmap for group %u not in group "
2330                                "(block %llu)!", i, inode_bitmap);
2331                         return 0;
2332                 }
2333                 inode_table = ext4_inode_table(sb, gdp);
2334                 if (inode_table == sb_block) {
2335                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2336                                  "Inode table for group %u overlaps "
2337                                  "superblock", i);
2338                         if (!(sb->s_flags & MS_RDONLY))
2339                                 return 0;
2340                 }
2341                 if (inode_table >= sb_block + 1 &&
2342                     inode_table <= last_bg_block) {
2343                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2344                                  "Inode table for group %u overlaps "
2345                                  "block group descriptors", i);
2346                         if (!(sb->s_flags & MS_RDONLY))
2347                                 return 0;
2348                 }
2349                 if (inode_table < first_block ||
2350                     inode_table + sbi->s_itb_per_group - 1 > last_block) {
2351                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2352                                "Inode table for group %u not in group "
2353                                "(block %llu)!", i, inode_table);
2354                         return 0;
2355                 }
2356                 ext4_lock_group(sb, i);
2357                 if (!ext4_group_desc_csum_verify(sb, i, gdp)) {
2358                         ext4_msg(sb, KERN_ERR, "ext4_check_descriptors: "
2359                                  "Checksum for group %u failed (%u!=%u)",
2360                                  i, le16_to_cpu(ext4_group_desc_csum(sb, i,
2361                                      gdp)), le16_to_cpu(gdp->bg_checksum));
2362                         if (!(sb->s_flags & MS_RDONLY)) {
2363                                 ext4_unlock_group(sb, i);
2364                                 return 0;
2365                         }
2366                 }
2367                 ext4_unlock_group(sb, i);
2368                 if (!flexbg_flag)
2369                         first_block += EXT4_BLOCKS_PER_GROUP(sb);
2370         }
2371         if (NULL != first_not_zeroed)
2372                 *first_not_zeroed = grp;
2373         return 1;
2374 }
2375
2376 /* ext4_orphan_cleanup() walks a singly-linked list of inodes (starting at
2377  * the superblock) which were deleted from all directories, but held open by
2378  * a process at the time of a crash.  We walk the list and try to delete these
2379  * inodes at recovery time (only with a read-write filesystem).
2380  *
2381  * In order to keep the orphan inode chain consistent during traversal (in
2382  * case of crash during recovery), we link each inode into the superblock
2383  * orphan list_head and handle it the same way as an inode deletion during
2384  * normal operation (which journals the operations for us).
2385  *
2386  * We only do an iget() and an iput() on each inode, which is very safe if we
2387  * accidentally point at an in-use or already deleted inode.  The worst that
2388  * can happen in this case is that we get a "bit already cleared" message from
2389  * ext4_free_inode().  The only reason we would point at a wrong inode is if
2390  * e2fsck was run on this filesystem, and it must have already done the orphan
2391  * inode cleanup for us, so we can safely abort without any further action.
2392  */
2393 static void ext4_orphan_cleanup(struct super_block *sb,
2394                                 struct ext4_super_block *es)
2395 {
2396         unsigned int s_flags = sb->s_flags;
2397         int nr_orphans = 0, nr_truncates = 0;
2398 #ifdef CONFIG_QUOTA
2399         int quota_update = 0;
2400         int i;
2401 #endif
2402         if (!es->s_last_orphan) {
2403                 jbd_debug(4, "no orphan inodes to clean up\n");
2404                 return;
2405         }
2406
2407         if (bdev_read_only(sb->s_bdev)) {
2408                 ext4_msg(sb, KERN_ERR, "write access "
2409                         "unavailable, skipping orphan cleanup");
2410                 return;
2411         }
2412
2413         /* Check if feature set would not allow a r/w mount */
2414         if (!ext4_feature_set_ok(sb, 0)) {
2415                 ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to "
2416                          "unknown ROCOMPAT features");
2417                 return;
2418         }
2419
2420         if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2421                 /* don't clear list on RO mount w/ errors */
2422                 if (es->s_last_orphan && !(s_flags & MS_RDONLY)) {
2423                         ext4_msg(sb, KERN_INFO, "Errors on filesystem, "
2424                                   "clearing orphan list.\n");
2425                         es->s_last_orphan = 0;
2426                 }
2427                 jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2428                 return;
2429         }
2430
2431         if (s_flags & MS_RDONLY) {
2432                 ext4_msg(sb, KERN_INFO, "orphan cleanup on readonly fs");
2433                 sb->s_flags &= ~MS_RDONLY;
2434         }
2435 #ifdef CONFIG_QUOTA
2436         /* Needed for iput() to work correctly and not trash data */
2437         sb->s_flags |= MS_ACTIVE;
2438
2439         /*
2440          * Turn on quotas which were not enabled for read-only mounts if
2441          * filesystem has quota feature, so that they are updated correctly.
2442          */
2443         if (ext4_has_feature_quota(sb) && (s_flags & MS_RDONLY)) {
2444                 int ret = ext4_enable_quotas(sb);
2445
2446                 if (!ret)
2447                         quota_update = 1;
2448                 else
2449                         ext4_msg(sb, KERN_ERR,
2450                                 "Cannot turn on quotas: error %d", ret);
2451         }
2452
2453         /* Turn on journaled quotas used for old sytle */
2454         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2455                 if (EXT4_SB(sb)->s_qf_names[i]) {
2456                         int ret = ext4_quota_on_mount(sb, i);
2457
2458                         if (!ret)
2459                                 quota_update = 1;
2460                         else
2461                                 ext4_msg(sb, KERN_ERR,
2462                                         "Cannot turn on journaled "
2463                                         "quota: type %d: error %d", i, ret);
2464                 }
2465         }
2466 #endif
2467
2468         while (es->s_last_orphan) {
2469                 struct inode *inode;
2470
2471                 /*
2472                  * We may have encountered an error during cleanup; if
2473                  * so, skip the rest.
2474                  */
2475                 if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) {
2476                         jbd_debug(1, "Skipping orphan recovery on fs with errors.\n");
2477                         es->s_last_orphan = 0;
2478                         break;
2479                 }
2480
2481                 inode = ext4_orphan_get(sb, le32_to_cpu(es->s_last_orphan));
2482                 if (IS_ERR(inode)) {
2483                         es->s_last_orphan = 0;
2484                         break;
2485                 }
2486
2487                 list_add(&EXT4_I(inode)->i_orphan, &EXT4_SB(sb)->s_orphan);
2488                 dquot_initialize(inode);
2489                 if (inode->i_nlink) {
2490                         if (test_opt(sb, DEBUG))
2491                                 ext4_msg(sb, KERN_DEBUG,
2492                                         "%s: truncating inode %lu to %lld bytes",
2493                                         __func__, inode->i_ino, inode->i_size);
2494                         jbd_debug(2, "truncating inode %lu to %lld bytes\n",
2495                                   inode->i_ino, inode->i_size);
2496                         inode_lock(inode);
2497                         truncate_inode_pages(inode->i_mapping, inode->i_size);
2498                         ext4_truncate(inode);
2499                         inode_unlock(inode);
2500                         nr_truncates++;
2501                 } else {
2502                         if (test_opt(sb, DEBUG))
2503                                 ext4_msg(sb, KERN_DEBUG,
2504                                         "%s: deleting unreferenced inode %lu",
2505                                         __func__, inode->i_ino);
2506                         jbd_debug(2, "deleting unreferenced inode %lu\n",
2507                                   inode->i_ino);
2508                         nr_orphans++;
2509                 }
2510                 iput(inode);  /* The delete magic happens here! */
2511         }
2512
2513 #define PLURAL(x) (x), ((x) == 1) ? "" : "s"
2514
2515         if (nr_orphans)
2516                 ext4_msg(sb, KERN_INFO, "%d orphan inode%s deleted",
2517                        PLURAL(nr_orphans));
2518         if (nr_truncates)
2519                 ext4_msg(sb, KERN_INFO, "%d truncate%s cleaned up",
2520                        PLURAL(nr_truncates));
2521 #ifdef CONFIG_QUOTA
2522         /* Turn off quotas if they were enabled for orphan cleanup */
2523         if (quota_update) {
2524                 for (i = 0; i < EXT4_MAXQUOTAS; i++) {
2525                         if (sb_dqopt(sb)->files[i])
2526                                 dquot_quota_off(sb, i);
2527                 }
2528         }
2529 #endif
2530         sb->s_flags = s_flags; /* Restore MS_RDONLY status */
2531 }
2532
2533 /*
2534  * Maximal extent format file size.
2535  * Resulting logical blkno at s_maxbytes must fit in our on-disk
2536  * extent format containers, within a sector_t, and within i_blocks
2537  * in the vfs.  ext4 inode has 48 bits of i_block in fsblock units,
2538  * so that won't be a limiting factor.
2539  *
2540  * However there is other limiting factor. We do store extents in the form
2541  * of starting block and length, hence the resulting length of the extent
2542  * covering maximum file size must fit into on-disk format containers as
2543  * well. Given that length is always by 1 unit bigger than max unit (because
2544  * we count 0 as well) we have to lower the s_maxbytes by one fs block.
2545  *
2546  * Note, this does *not* consider any metadata overhead for vfs i_blocks.
2547  */
2548 static loff_t ext4_max_size(int blkbits, int has_huge_files)
2549 {
2550         loff_t res;
2551         loff_t upper_limit = MAX_LFS_FILESIZE;
2552
2553         /* small i_blocks in vfs inode? */
2554         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2555                 /*
2556                  * CONFIG_LBDAF is not enabled implies the inode
2557                  * i_block represent total blocks in 512 bytes
2558                  * 32 == size of vfs inode i_blocks * 8
2559                  */
2560                 upper_limit = (1LL << 32) - 1;
2561
2562                 /* total blocks in file system block size */
2563                 upper_limit >>= (blkbits - 9);
2564                 upper_limit <<= blkbits;
2565         }
2566
2567         /*
2568          * 32-bit extent-start container, ee_block. We lower the maxbytes
2569          * by one fs block, so ee_len can cover the extent of maximum file
2570          * size
2571          */
2572         res = (1LL << 32) - 1;
2573         res <<= blkbits;
2574
2575         /* Sanity check against vm- & vfs- imposed limits */
2576         if (res > upper_limit)
2577                 res = upper_limit;
2578
2579         return res;
2580 }
2581
2582 /*
2583  * Maximal bitmap file size.  There is a direct, and {,double-,triple-}indirect
2584  * block limit, and also a limit of (2^48 - 1) 512-byte sectors in i_blocks.
2585  * We need to be 1 filesystem block less than the 2^48 sector limit.
2586  */
2587 static loff_t ext4_max_bitmap_size(int bits, int has_huge_files)
2588 {
2589         loff_t res = EXT4_NDIR_BLOCKS;
2590         int meta_blocks;
2591         loff_t upper_limit;
2592         /* This is calculated to be the largest file size for a dense, block
2593          * mapped file such that the file's total number of 512-byte sectors,
2594          * including data and all indirect blocks, does not exceed (2^48 - 1).
2595          *
2596          * __u32 i_blocks_lo and _u16 i_blocks_high represent the total
2597          * number of 512-byte sectors of the file.
2598          */
2599
2600         if (!has_huge_files || sizeof(blkcnt_t) < sizeof(u64)) {
2601                 /*
2602                  * !has_huge_files or CONFIG_LBDAF not enabled implies that
2603                  * the inode i_block field represents total file blocks in
2604                  * 2^32 512-byte sectors == size of vfs inode i_blocks * 8
2605                  */
2606                 upper_limit = (1LL << 32) - 1;
2607
2608                 /* total blocks in file system block size */
2609                 upper_limit >>= (bits - 9);
2610
2611         } else {
2612                 /*
2613                  * We use 48 bit ext4_inode i_blocks
2614                  * With EXT4_HUGE_FILE_FL set the i_blocks
2615                  * represent total number of blocks in
2616                  * file system block size
2617                  */
2618                 upper_limit = (1LL << 48) - 1;
2619
2620         }
2621
2622         /* indirect blocks */
2623         meta_blocks = 1;
2624         /* double indirect blocks */
2625         meta_blocks += 1 + (1LL << (bits-2));
2626         /* tripple indirect blocks */
2627         meta_blocks += 1 + (1LL << (bits-2)) + (1LL << (2*(bits-2)));
2628
2629         upper_limit -= meta_blocks;
2630         upper_limit <<= bits;
2631
2632         res += 1LL << (bits-2);
2633         res += 1LL << (2*(bits-2));
2634         res += 1LL << (3*(bits-2));
2635         res <<= bits;
2636         if (res > upper_limit)
2637                 res = upper_limit;
2638
2639         if (res > MAX_LFS_FILESIZE)
2640                 res = MAX_LFS_FILESIZE;
2641
2642         return res;
2643 }
2644
2645 static ext4_fsblk_t descriptor_loc(struct super_block *sb,
2646                                    ext4_fsblk_t logical_sb_block, int nr)
2647 {
2648         struct ext4_sb_info *sbi = EXT4_SB(sb);
2649         ext4_group_t bg, first_meta_bg;
2650         int has_super = 0;
2651
2652         first_meta_bg = le32_to_cpu(sbi->s_es->s_first_meta_bg);
2653
2654         if (!ext4_has_feature_meta_bg(sb) || nr < first_meta_bg)
2655                 return logical_sb_block + nr + 1;
2656         bg = sbi->s_desc_per_block * nr;
2657         if (ext4_bg_has_super(sb, bg))
2658                 has_super = 1;
2659
2660         /*
2661          * If we have a meta_bg fs with 1k blocks, group 0's GDT is at
2662          * block 2, not 1.  If s_first_data_block == 0 (bigalloc is enabled
2663          * on modern mke2fs or blksize > 1k on older mke2fs) then we must
2664          * compensate.
2665          */
2666         if (sb->s_blocksize == 1024 && nr == 0 &&
2667             le32_to_cpu(EXT4_SB(sb)->s_es->s_first_data_block) == 0)
2668                 has_super++;
2669
2670         return (has_super + ext4_group_first_block_no(sb, bg));
2671 }
2672
2673 /**
2674  * ext4_get_stripe_size: Get the stripe size.
2675  * @sbi: In memory super block info
2676  *
2677  * If we have specified it via mount option, then
2678  * use the mount option value. If the value specified at mount time is
2679  * greater than the blocks per group use the super block value.
2680  * If the super block value is greater than blocks per group return 0.
2681  * Allocator needs it be less than blocks per group.
2682  *
2683  */
2684 static unsigned long ext4_get_stripe_size(struct ext4_sb_info *sbi)
2685 {
2686         unsigned long stride = le16_to_cpu(sbi->s_es->s_raid_stride);
2687         unsigned long stripe_width =
2688                         le32_to_cpu(sbi->s_es->s_raid_stripe_width);
2689         int ret;
2690
2691         if (sbi->s_stripe && sbi->s_stripe <= sbi->s_blocks_per_group)
2692                 ret = sbi->s_stripe;
2693         else if (stripe_width && stripe_width <= sbi->s_blocks_per_group)
2694                 ret = stripe_width;
2695         else if (stride && stride <= sbi->s_blocks_per_group)
2696                 ret = stride;
2697         else
2698                 ret = 0;
2699
2700         /*
2701          * If the stripe width is 1, this makes no sense and
2702          * we set it to 0 to turn off stripe handling code.
2703          */
2704         if (ret <= 1)
2705                 ret = 0;
2706
2707         return ret;
2708 }
2709
2710 /*
2711  * Check whether this filesystem can be mounted based on
2712  * the features present and the RDONLY/RDWR mount requested.
2713  * Returns 1 if this filesystem can be mounted as requested,
2714  * 0 if it cannot be.
2715  */
2716 static int ext4_feature_set_ok(struct super_block *sb, int readonly)
2717 {
2718         if (ext4_has_unknown_ext4_incompat_features(sb)) {
2719                 ext4_msg(sb, KERN_ERR,
2720                         "Couldn't mount because of "
2721                         "unsupported optional features (%x)",
2722                         (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_incompat) &
2723                         ~EXT4_FEATURE_INCOMPAT_SUPP));
2724                 return 0;
2725         }
2726
2727         if (readonly)
2728                 return 1;
2729
2730         if (ext4_has_feature_readonly(sb)) {
2731                 ext4_msg(sb, KERN_INFO, "filesystem is read-only");
2732                 sb->s_flags |= MS_RDONLY;
2733                 return 1;
2734         }
2735
2736         /* Check that feature set is OK for a read-write mount */
2737         if (ext4_has_unknown_ext4_ro_compat_features(sb)) {
2738                 ext4_msg(sb, KERN_ERR, "couldn't mount RDWR because of "
2739                          "unsupported optional features (%x)",
2740                          (le32_to_cpu(EXT4_SB(sb)->s_es->s_feature_ro_compat) &
2741                                 ~EXT4_FEATURE_RO_COMPAT_SUPP));
2742                 return 0;
2743         }
2744         /*
2745          * Large file size enabled file system can only be mounted
2746          * read-write on 32-bit systems if kernel is built with CONFIG_LBDAF
2747          */
2748         if (ext4_has_feature_huge_file(sb)) {
2749                 if (sizeof(blkcnt_t) < sizeof(u64)) {
2750                         ext4_msg(sb, KERN_ERR, "Filesystem with huge files "
2751                                  "cannot be mounted RDWR without "
2752                                  "CONFIG_LBDAF");
2753                         return 0;
2754                 }
2755         }
2756         if (ext4_has_feature_bigalloc(sb) && !ext4_has_feature_extents(sb)) {
2757                 ext4_msg(sb, KERN_ERR,
2758                          "Can't support bigalloc feature without "
2759                          "extents feature\n");
2760                 return 0;
2761         }
2762
2763 #if !IS_ENABLED(CONFIG_QUOTA) || !IS_ENABLED(CONFIG_QFMT_V2)
2764         if (!readonly && (ext4_has_feature_quota(sb) ||
2765                           ext4_has_feature_project(sb))) {
2766                 ext4_msg(sb, KERN_ERR,
2767                          "The kernel was not built with CONFIG_QUOTA and CONFIG_QFMT_V2");
2768                 return 0;
2769         }
2770 #endif  /* CONFIG_QUOTA */
2771         return 1;
2772 }
2773
2774 /*
2775  * This function is called once a day if we have errors logged
2776  * on the file system
2777  */
2778 static void print_daily_error_info(unsigned long arg)
2779 {
2780         struct super_block *sb = (struct super_block *) arg;
2781         struct ext4_sb_info *sbi;
2782         struct ext4_super_block *es;
2783
2784         sbi = EXT4_SB(sb);
2785         es = sbi->s_es;
2786
2787         if (es->s_error_count)
2788                 /* fsck newer than v1.41.13 is needed to clean this condition. */
2789                 ext4_msg(sb, KERN_NOTICE, "error count since last fsck: %u",
2790                          le32_to_cpu(es->s_error_count));
2791         if (es->s_first_error_time) {
2792                 printk(KERN_NOTICE "EXT4-fs (%s): initial error at time %u: %.*s:%d",
2793                        sb->s_id, le32_to_cpu(es->s_first_error_time),
2794                        (int) sizeof(es->s_first_error_func),
2795                        es->s_first_error_func,
2796                        le32_to_cpu(es->s_first_error_line));
2797                 if (es->s_first_error_ino)
2798                         printk(KERN_CONT ": inode %u",
2799                                le32_to_cpu(es->s_first_error_ino));
2800                 if (es->s_first_error_block)
2801                         printk(KERN_CONT ": block %llu", (unsigned long long)
2802                                le64_to_cpu(es->s_first_error_block));
2803                 printk(KERN_CONT "\n");
2804         }
2805         if (es->s_last_error_time) {
2806                 printk(KERN_NOTICE "EXT4-fs (%s): last error at time %u: %.*s:%d",
2807                        sb->s_id, le32_to_cpu(es->s_last_error_time),
2808                        (int) sizeof(es->s_last_error_func),
2809                        es->s_last_error_func,
2810                        le32_to_cpu(es->s_last_error_line));
2811                 if (es->s_last_error_ino)
2812                         printk(KERN_CONT ": inode %u",
2813                                le32_to_cpu(es->s_last_error_ino));
2814                 if (es->s_last_error_block)
2815                         printk(KERN_CONT ": block %llu", (unsigned long long)
2816                                le64_to_cpu(es->s_last_error_block));
2817                 printk(KERN_CONT "\n");
2818         }
2819         mod_timer(&sbi->s_err_report, jiffies + 24*60*60*HZ);  /* Once a day */
2820 }
2821
2822 /* Find next suitable group and run ext4_init_inode_table */
2823 static int ext4_run_li_request(struct ext4_li_request *elr)
2824 {
2825         struct ext4_group_desc *gdp = NULL;
2826         ext4_group_t group, ngroups;
2827         struct super_block *sb;
2828         unsigned long timeout = 0;
2829         int ret = 0;
2830
2831         sb = elr->lr_super;
2832         ngroups = EXT4_SB(sb)->s_groups_count;
2833
2834         for (group = elr->lr_next_group; group < ngroups; group++) {
2835                 gdp = ext4_get_group_desc(sb, group, NULL);
2836                 if (!gdp) {
2837                         ret = 1;
2838                         break;
2839                 }
2840
2841                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
2842                         break;
2843         }
2844
2845         if (group >= ngroups)
2846                 ret = 1;
2847
2848         if (!ret) {
2849                 timeout = jiffies;
2850                 ret = ext4_init_inode_table(sb, group,
2851                                             elr->lr_timeout ? 0 : 1);
2852                 if (elr->lr_timeout == 0) {
2853                         timeout = (jiffies - timeout) *
2854                                   elr->lr_sbi->s_li_wait_mult;
2855                         elr->lr_timeout = timeout;
2856                 }
2857                 elr->lr_next_sched = jiffies + elr->lr_timeout;
2858                 elr->lr_next_group = group + 1;
2859         }
2860         return ret;
2861 }
2862
2863 /*
2864  * Remove lr_request from the list_request and free the
2865  * request structure. Should be called with li_list_mtx held
2866  */
2867 static void ext4_remove_li_request(struct ext4_li_request *elr)
2868 {
2869         struct ext4_sb_info *sbi;
2870
2871         if (!elr)
2872                 return;
2873
2874         sbi = elr->lr_sbi;
2875
2876         list_del(&elr->lr_request);
2877         sbi->s_li_request = NULL;
2878         kfree(elr);
2879 }
2880
2881 static void ext4_unregister_li_request(struct super_block *sb)
2882 {
2883         mutex_lock(&ext4_li_mtx);
2884         if (!ext4_li_info) {
2885                 mutex_unlock(&ext4_li_mtx);
2886                 return;
2887         }
2888
2889         mutex_lock(&ext4_li_info->li_list_mtx);
2890         ext4_remove_li_request(EXT4_SB(sb)->s_li_request);
2891         mutex_unlock(&ext4_li_info->li_list_mtx);
2892         mutex_unlock(&ext4_li_mtx);
2893 }
2894
2895 static struct task_struct *ext4_lazyinit_task;
2896
2897 /*
2898  * This is the function where ext4lazyinit thread lives. It walks
2899  * through the request list searching for next scheduled filesystem.
2900  * When such a fs is found, run the lazy initialization request
2901  * (ext4_rn_li_request) and keep track of the time spend in this
2902  * function. Based on that time we compute next schedule time of
2903  * the request. When walking through the list is complete, compute
2904  * next waking time and put itself into sleep.
2905  */
2906 static int ext4_lazyinit_thread(void *arg)
2907 {
2908         struct ext4_lazy_init *eli = (struct ext4_lazy_init *)arg;
2909         struct list_head *pos, *n;
2910         struct ext4_li_request *elr;
2911         unsigned long next_wakeup, cur;
2912
2913         BUG_ON(NULL == eli);
2914
2915 cont_thread:
2916         while (true) {
2917                 next_wakeup = MAX_JIFFY_OFFSET;
2918
2919                 mutex_lock(&eli->li_list_mtx);
2920                 if (list_empty(&eli->li_request_list)) {
2921                         mutex_unlock(&eli->li_list_mtx);
2922                         goto exit_thread;
2923                 }
2924                 list_for_each_safe(pos, n, &eli->li_request_list) {
2925                         int err = 0;
2926                         int progress = 0;
2927                         elr = list_entry(pos, struct ext4_li_request,
2928                                          lr_request);
2929
2930                         if (time_before(jiffies, elr->lr_next_sched)) {
2931                                 if (time_before(elr->lr_next_sched, next_wakeup))
2932                                         next_wakeup = elr->lr_next_sched;
2933                                 continue;
2934                         }
2935                         if (down_read_trylock(&elr->lr_super->s_umount)) {
2936                                 if (sb_start_write_trylock(elr->lr_super)) {
2937                                         progress = 1;
2938                                         /*
2939                                          * We hold sb->s_umount, sb can not
2940                                          * be removed from the list, it is
2941                                          * now safe to drop li_list_mtx
2942                                          */
2943                                         mutex_unlock(&eli->li_list_mtx);
2944                                         err = ext4_run_li_request(elr);
2945                                         sb_end_write(elr->lr_super);
2946                                         mutex_lock(&eli->li_list_mtx);
2947                                         n = pos->next;
2948                                 }
2949                                 up_read((&elr->lr_super->s_umount));
2950                         }
2951                         /* error, remove the lazy_init job */
2952                         if (err) {
2953                                 ext4_remove_li_request(elr);
2954                                 continue;
2955                         }
2956                         if (!progress) {
2957                                 elr->lr_next_sched = jiffies +
2958                                         (prandom_u32()
2959                                          % (EXT4_DEF_LI_MAX_START_DELAY * HZ));
2960                         }
2961                         if (time_before(elr->lr_next_sched, next_wakeup))
2962                                 next_wakeup = elr->lr_next_sched;
2963                 }
2964                 mutex_unlock(&eli->li_list_mtx);
2965
2966                 try_to_freeze();
2967
2968                 cur = jiffies;
2969                 if ((time_after_eq(cur, next_wakeup)) ||
2970                     (MAX_JIFFY_OFFSET == next_wakeup)) {
2971                         cond_resched();
2972                         continue;
2973                 }
2974
2975                 schedule_timeout_interruptible(next_wakeup - cur);
2976
2977                 if (kthread_should_stop()) {
2978                         ext4_clear_request_list();
2979                         goto exit_thread;
2980                 }
2981         }
2982
2983 exit_thread:
2984         /*
2985          * It looks like the request list is empty, but we need
2986          * to check it under the li_list_mtx lock, to prevent any
2987          * additions into it, and of course we should lock ext4_li_mtx
2988          * to atomically free the list and ext4_li_info, because at
2989          * this point another ext4 filesystem could be registering
2990          * new one.
2991          */
2992         mutex_lock(&ext4_li_mtx);
2993         mutex_lock(&eli->li_list_mtx);
2994         if (!list_empty(&eli->li_request_list)) {
2995                 mutex_unlock(&eli->li_list_mtx);
2996                 mutex_unlock(&ext4_li_mtx);
2997                 goto cont_thread;
2998         }
2999         mutex_unlock(&eli->li_list_mtx);
3000         kfree(ext4_li_info);
3001         ext4_li_info = NULL;
3002         mutex_unlock(&ext4_li_mtx);
3003
3004         return 0;
3005 }
3006
3007 static void ext4_clear_request_list(void)
3008 {
3009         struct list_head *pos, *n;
3010         struct ext4_li_request *elr;
3011
3012         mutex_lock(&ext4_li_info->li_list_mtx);
3013         list_for_each_safe(pos, n, &ext4_li_info->li_request_list) {
3014                 elr = list_entry(pos, struct ext4_li_request,
3015                                  lr_request);
3016                 ext4_remove_li_request(elr);
3017         }
3018         mutex_unlock(&ext4_li_info->li_list_mtx);
3019 }
3020
3021 static int ext4_run_lazyinit_thread(void)
3022 {
3023         ext4_lazyinit_task = kthread_run(ext4_lazyinit_thread,
3024                                          ext4_li_info, "ext4lazyinit");
3025         if (IS_ERR(ext4_lazyinit_task)) {
3026                 int err = PTR_ERR(ext4_lazyinit_task);
3027                 ext4_clear_request_list();
3028                 kfree(ext4_li_info);
3029                 ext4_li_info = NULL;
3030                 printk(KERN_CRIT "EXT4-fs: error %d creating inode table "
3031                                  "initialization thread\n",
3032                                  err);
3033                 return err;
3034         }
3035         ext4_li_info->li_state |= EXT4_LAZYINIT_RUNNING;
3036         return 0;
3037 }
3038
3039 /*
3040  * Check whether it make sense to run itable init. thread or not.
3041  * If there is at least one uninitialized inode table, return
3042  * corresponding group number, else the loop goes through all
3043  * groups and return total number of groups.
3044  */
3045 static ext4_group_t ext4_has_uninit_itable(struct super_block *sb)
3046 {
3047         ext4_group_t group, ngroups = EXT4_SB(sb)->s_groups_count;
3048         struct ext4_group_desc *gdp = NULL;
3049
3050         if (!ext4_has_group_desc_csum(sb))
3051                 return ngroups;
3052
3053         for (group = 0; group < ngroups; group++) {
3054                 gdp = ext4_get_group_desc(sb, group, NULL);
3055                 if (!gdp)
3056                         continue;
3057
3058                 if (!(gdp->bg_flags & cpu_to_le16(EXT4_BG_INODE_ZEROED)))
3059                         break;
3060         }
3061
3062         return group;
3063 }
3064
3065 static int ext4_li_info_new(void)
3066 {
3067         struct ext4_lazy_init *eli = NULL;
3068
3069         eli = kzalloc(sizeof(*eli), GFP_KERNEL);
3070         if (!eli)
3071                 return -ENOMEM;
3072
3073         INIT_LIST_HEAD(&eli->li_request_list);
3074         mutex_init(&eli->li_list_mtx);
3075
3076         eli->li_state |= EXT4_LAZYINIT_QUIT;
3077
3078         ext4_li_info = eli;
3079
3080         return 0;
3081 }
3082
3083 static struct ext4_li_request *ext4_li_request_new(struct super_block *sb,
3084                                             ext4_group_t start)
3085 {
3086         struct ext4_sb_info *sbi = EXT4_SB(sb);
3087         struct ext4_li_request *elr;
3088
3089         elr = kzalloc(sizeof(*elr), GFP_KERNEL);
3090         if (!elr)
3091                 return NULL;
3092
3093         elr->lr_super = sb;
3094         elr->lr_sbi = sbi;
3095         elr->lr_next_group = start;
3096
3097         /*
3098          * Randomize first schedule time of the request to
3099          * spread the inode table initialization requests
3100          * better.
3101          */
3102         elr->lr_next_sched = jiffies + (prandom_u32() %
3103                                 (EXT4_DEF_LI_MAX_START_DELAY * HZ));
3104         return elr;
3105 }
3106
3107 int ext4_register_li_request(struct super_block *sb,
3108                              ext4_group_t first_not_zeroed)
3109 {
3110         struct ext4_sb_info *sbi = EXT4_SB(sb);
3111         struct ext4_li_request *elr = NULL;
3112         ext4_group_t ngroups = EXT4_SB(sb)->s_groups_count;
3113         int ret = 0;
3114
3115         mutex_lock(&ext4_li_mtx);
3116         if (sbi->s_li_request != NULL) {
3117                 /*
3118                  * Reset timeout so it can be computed again, because
3119                  * s_li_wait_mult might have changed.
3120                  */
3121                 sbi->s_li_request->lr_timeout = 0;
3122                 goto out;
3123         }
3124
3125         if (first_not_zeroed == ngroups ||
3126             (sb->s_flags & MS_RDONLY) ||
3127             !test_opt(sb, INIT_INODE_TABLE))
3128                 goto out;
3129
3130         elr = ext4_li_request_new(sb, first_not_zeroed);
3131         if (!elr) {
3132                 ret = -ENOMEM;
3133                 goto out;
3134         }
3135
3136         if (NULL == ext4_li_info) {
3137                 ret = ext4_li_info_new();
3138                 if (ret)
3139                         goto out;
3140         }
3141
3142         mutex_lock(&ext4_li_info->li_list_mtx);
3143         list_add(&elr->lr_request, &ext4_li_info->li_request_list);
3144         mutex_unlock(&ext4_li_info->li_list_mtx);
3145
3146         sbi->s_li_request = elr;
3147         /*
3148          * set elr to NULL here since it has been inserted to
3149          * the request_list and the removal and free of it is
3150          * handled by ext4_clear_request_list from now on.
3151          */
3152         elr = NULL;
3153
3154         if (!(ext4_li_info->li_state & EXT4_LAZYINIT_RUNNING)) {
3155                 ret = ext4_run_lazyinit_thread();
3156                 if (ret)
3157                         goto out;
3158         }
3159 out:
3160         mutex_unlock(&ext4_li_mtx);
3161         if (ret)
3162                 kfree(elr);
3163         return ret;
3164 }
3165
3166 /*
3167  * We do not need to lock anything since this is called on
3168  * module unload.
3169  */
3170 static void ext4_destroy_lazyinit_thread(void)
3171 {
3172         /*
3173          * If thread exited earlier
3174          * there's nothing to be done.
3175          */
3176         if (!ext4_li_info || !ext4_lazyinit_task)
3177                 return;
3178
3179         kthread_stop(ext4_lazyinit_task);
3180 }
3181
3182 static int set_journal_csum_feature_set(struct super_block *sb)
3183 {
3184         int ret = 1;
3185         int compat, incompat;
3186         struct ext4_sb_info *sbi = EXT4_SB(sb);
3187
3188         if (ext4_has_metadata_csum(sb)) {
3189                 /* journal checksum v3 */
3190                 compat = 0;
3191                 incompat = JBD2_FEATURE_INCOMPAT_CSUM_V3;
3192         } else {
3193                 /* journal checksum v1 */
3194                 compat = JBD2_FEATURE_COMPAT_CHECKSUM;
3195                 incompat = 0;
3196         }
3197
3198         jbd2_journal_clear_features(sbi->s_journal,
3199                         JBD2_FEATURE_COMPAT_CHECKSUM, 0,
3200                         JBD2_FEATURE_INCOMPAT_CSUM_V3 |
3201                         JBD2_FEATURE_INCOMPAT_CSUM_V2);
3202         if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
3203                 ret = jbd2_journal_set_features(sbi->s_journal,
3204                                 compat, 0,
3205                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT |
3206                                 incompat);
3207         } else if (test_opt(sb, JOURNAL_CHECKSUM)) {
3208                 ret = jbd2_journal_set_features(sbi->s_journal,
3209                                 compat, 0,
3210                                 incompat);
3211                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3212                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3213         } else {
3214                 jbd2_journal_clear_features(sbi->s_journal, 0, 0,
3215                                 JBD2_FEATURE_INCOMPAT_ASYNC_COMMIT);
3216         }
3217
3218         return ret;
3219 }
3220
3221 /*
3222  * Note: calculating the overhead so we can be compatible with
3223  * historical BSD practice is quite difficult in the face of
3224  * clusters/bigalloc.  This is because multiple metadata blocks from
3225  * different block group can end up in the same allocation cluster.
3226  * Calculating the exact overhead in the face of clustered allocation
3227  * requires either O(all block bitmaps) in memory or O(number of block
3228  * groups**2) in time.  We will still calculate the superblock for
3229  * older file systems --- and if we come across with a bigalloc file
3230  * system with zero in s_overhead_clusters the estimate will be close to
3231  * correct especially for very large cluster sizes --- but for newer
3232  * file systems, it's better to calculate this figure once at mkfs
3233  * time, and store it in the superblock.  If the superblock value is
3234  * present (even for non-bigalloc file systems), we will use it.
3235  */
3236 static int count_overhead(struct super_block *sb, ext4_group_t grp,
3237                           char *buf)
3238 {
3239         struct ext4_sb_info     *sbi = EXT4_SB(sb);
3240         struct ext4_group_desc  *gdp;
3241         ext4_fsblk_t            first_block, last_block, b;
3242         ext4_group_t            i, ngroups = ext4_get_groups_count(sb);
3243         int                     s, j, count = 0;
3244         int                     has_super = ext4_bg_has_super(sb, grp);
3245
3246         if (!ext4_has_feature_bigalloc(sb))
3247                 return (has_super + ext4_bg_num_gdb(sb, grp) +
3248                         (has_super ? le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) : 0) +
3249                         sbi->s_itb_per_group + 2);
3250
3251         first_block = le32_to_cpu(sbi->s_es->s_first_data_block) +
3252                 (grp * EXT4_BLOCKS_PER_GROUP(sb));
3253         last_block = first_block + EXT4_BLOCKS_PER_GROUP(sb) - 1;
3254         for (i = 0; i < ngroups; i++) {
3255                 gdp = ext4_get_group_desc(sb, i, NULL);
3256                 b = ext4_block_bitmap(sb, gdp);
3257                 if (b >= first_block && b <= last_block) {
3258                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3259                         count++;
3260                 }
3261                 b = ext4_inode_bitmap(sb, gdp);
3262                 if (b >= first_block && b <= last_block) {
3263                         ext4_set_bit(EXT4_B2C(sbi, b - first_block), buf);
3264                         count++;
3265                 }
3266                 b = ext4_inode_table(sb, gdp);
3267                 if (b >= first_block && b + sbi->s_itb_per_group <= last_block)
3268                         for (j = 0; j < sbi->s_itb_per_group; j++, b++) {
3269                                 int c = EXT4_B2C(sbi, b - first_block);
3270                                 ext4_set_bit(c, buf);
3271                                 count++;
3272                         }
3273                 if (i != grp)
3274                         continue;
3275                 s = 0;
3276                 if (ext4_bg_has_super(sb, grp)) {
3277                         ext4_set_bit(s++, buf);
3278                         count++;
3279                 }
3280                 j = ext4_bg_num_gdb(sb, grp);
3281                 if (s + j > EXT4_BLOCKS_PER_GROUP(sb)) {
3282                         ext4_error(sb, "Invalid number of block group "
3283                                    "descriptor blocks: %d", j);
3284                         j = EXT4_BLOCKS_PER_GROUP(sb) - s;
3285                 }
3286                 count += j;
3287                 for (; j > 0; j--)
3288                         ext4_set_bit(EXT4_B2C(sbi, s++), buf);
3289         }
3290         if (!count)
3291                 return 0;
3292         return EXT4_CLUSTERS_PER_GROUP(sb) -
3293                 ext4_count_free(buf, EXT4_CLUSTERS_PER_GROUP(sb) / 8);
3294 }
3295
3296 /*
3297  * Compute the overhead and stash it in sbi->s_overhead
3298  */
3299 int ext4_calculate_overhead(struct super_block *sb)
3300 {
3301         struct ext4_sb_info *sbi = EXT4_SB(sb);
3302         struct ext4_super_block *es = sbi->s_es;
3303         struct inode *j_inode;
3304         unsigned int j_blocks, j_inum = le32_to_cpu(es->s_journal_inum);
3305         ext4_group_t i, ngroups = ext4_get_groups_count(sb);
3306         ext4_fsblk_t overhead = 0;
3307         char *buf = (char *) get_zeroed_page(GFP_NOFS);
3308
3309         if (!buf)
3310                 return -ENOMEM;
3311
3312         /*
3313          * Compute the overhead (FS structures).  This is constant
3314          * for a given filesystem unless the number of block groups
3315          * changes so we cache the previous value until it does.
3316          */
3317
3318         /*
3319          * All of the blocks before first_data_block are overhead
3320          */
3321         overhead = EXT4_B2C(sbi, le32_to_cpu(es->s_first_data_block));
3322
3323         /*
3324          * Add the overhead found in each block group
3325          */
3326         for (i = 0; i < ngroups; i++) {
3327                 int blks;
3328
3329                 blks = count_overhead(sb, i, buf);
3330                 overhead += blks;
3331                 if (blks)
3332                         memset(buf, 0, PAGE_SIZE);
3333                 cond_resched();
3334         }
3335
3336         /*
3337          * Add the internal journal blocks whether the journal has been
3338          * loaded or not
3339          */
3340         if (sbi->s_journal && !sbi->journal_bdev)
3341                 overhead += EXT4_NUM_B2C(sbi, sbi->s_journal->j_maxlen);
3342         else if (ext4_has_feature_journal(sb) && !sbi->s_journal && j_inum) {
3343                 /* j_inum for internal journal is non-zero */
3344                 j_inode = ext4_get_journal_inode(sb, j_inum);
3345                 if (j_inode) {
3346                         j_blocks = j_inode->i_size >> sb->s_blocksize_bits;
3347                         overhead += EXT4_NUM_B2C(sbi, j_blocks);
3348                         iput(j_inode);
3349                 } else {
3350                         ext4_msg(sb, KERN_ERR, "can't get journal size");
3351                 }
3352         }
3353         sbi->s_overhead = overhead;
3354         smp_wmb();
3355         free_page((unsigned long) buf);
3356         return 0;
3357 }
3358
3359 static void ext4_clamp_want_extra_isize(struct super_block *sb)
3360 {
3361         struct ext4_sb_info *sbi = EXT4_SB(sb);
3362         struct ext4_super_block *es = sbi->s_es;
3363         unsigned def_extra_isize = sizeof(struct ext4_inode) -
3364                                                 EXT4_GOOD_OLD_INODE_SIZE;
3365
3366         if (sbi->s_inode_size == EXT4_GOOD_OLD_INODE_SIZE) {
3367                 sbi->s_want_extra_isize = 0;
3368                 return;
3369         }
3370         if (sbi->s_want_extra_isize < 4) {
3371                 sbi->s_want_extra_isize = def_extra_isize;
3372                 if (ext4_has_feature_extra_isize(sb)) {
3373                         if (sbi->s_want_extra_isize <
3374                             le16_to_cpu(es->s_want_extra_isize))
3375                                 sbi->s_want_extra_isize =
3376                                         le16_to_cpu(es->s_want_extra_isize);
3377                         if (sbi->s_want_extra_isize <
3378                             le16_to_cpu(es->s_min_extra_isize))
3379                                 sbi->s_want_extra_isize =
3380                                         le16_to_cpu(es->s_min_extra_isize);
3381                 }
3382         }
3383         /* Check if enough inode space is available */
3384         if ((sbi->s_want_extra_isize > sbi->s_inode_size) ||
3385             (EXT4_GOOD_OLD_INODE_SIZE + sbi->s_want_extra_isize >
3386                                                         sbi->s_inode_size)) {
3387                 sbi->s_want_extra_isize = def_extra_isize;
3388                 ext4_msg(sb, KERN_INFO,
3389                          "required extra inode space not available");
3390         }
3391 }
3392
3393 static void ext4_set_resv_clusters(struct super_block *sb)
3394 {
3395         ext4_fsblk_t resv_clusters;
3396         struct ext4_sb_info *sbi = EXT4_SB(sb);
3397
3398         /*
3399          * There's no need to reserve anything when we aren't using extents.
3400          * The space estimates are exact, there are no unwritten extents,
3401          * hole punching doesn't need new metadata... This is needed especially
3402          * to keep ext2/3 backward compatibility.
3403          */
3404         if (!ext4_has_feature_extents(sb))
3405                 return;
3406         /*
3407          * By default we reserve 2% or 4096 clusters, whichever is smaller.
3408          * This should cover the situations where we can not afford to run
3409          * out of space like for example punch hole, or converting
3410          * unwritten extents in delalloc path. In most cases such
3411          * allocation would require 1, or 2 blocks, higher numbers are
3412          * very rare.
3413          */
3414         resv_clusters = (ext4_blocks_count(sbi->s_es) >>
3415                          sbi->s_cluster_bits);
3416
3417         do_div(resv_clusters, 50);
3418         resv_clusters = min_t(ext4_fsblk_t, resv_clusters, 4096);
3419
3420         atomic64_set(&sbi->s_resv_clusters, resv_clusters);
3421 }
3422
3423 static int ext4_fill_super(struct super_block *sb, void *data, int silent)
3424 {
3425         char *orig_data = kstrdup(data, GFP_KERNEL);
3426         struct buffer_head *bh, **group_desc;
3427         struct ext4_super_block *es = NULL;
3428         struct ext4_sb_info *sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
3429         struct flex_groups **flex_groups;
3430         ext4_fsblk_t block;
3431         ext4_fsblk_t sb_block = get_sb_block(&data);
3432         ext4_fsblk_t logical_sb_block;
3433         unsigned long offset = 0;
3434         unsigned long journal_devnum = 0;
3435         unsigned long def_mount_opts;
3436         struct inode *root;
3437         const char *descr;
3438         int ret = -ENOMEM;
3439         int blocksize, clustersize;
3440         unsigned int db_count;
3441         unsigned int i;
3442         int needs_recovery, has_huge_files, has_bigalloc;
3443         __u64 blocks_count;
3444         int err = 0;
3445         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
3446         ext4_group_t first_not_zeroed;
3447
3448         if ((data && !orig_data) || !sbi)
3449                 goto out_free_base;
3450
3451         sbi->s_blockgroup_lock =
3452                 kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
3453         if (!sbi->s_blockgroup_lock)
3454                 goto out_free_base;
3455
3456         sb->s_fs_info = sbi;
3457         sbi->s_sb = sb;
3458         sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
3459         sbi->s_sb_block = sb_block;
3460         if (sb->s_bdev->bd_part)
3461                 sbi->s_sectors_written_start =
3462                         part_stat_read(sb->s_bdev->bd_part, sectors[1]);
3463
3464         /* Cleanup superblock name */
3465         strreplace(sb->s_id, '/', '!');
3466
3467         /* -EINVAL is default */
3468         ret = -EINVAL;
3469         blocksize = sb_min_blocksize(sb, EXT4_MIN_BLOCK_SIZE);
3470         if (!blocksize) {
3471                 ext4_msg(sb, KERN_ERR, "unable to set blocksize");
3472                 goto out_fail;
3473         }
3474
3475         /*
3476          * The ext4 superblock will not be buffer aligned for other than 1kB
3477          * block sizes.  We need to calculate the offset from buffer start.
3478          */
3479         if (blocksize != EXT4_MIN_BLOCK_SIZE) {
3480                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3481                 offset = do_div(logical_sb_block, blocksize);
3482         } else {
3483                 logical_sb_block = sb_block;
3484         }
3485
3486         if (!(bh = sb_bread_unmovable(sb, logical_sb_block))) {
3487                 ext4_msg(sb, KERN_ERR, "unable to read superblock");
3488                 goto out_fail;
3489         }
3490         /*
3491          * Note: s_es must be initialized as soon as possible because
3492          *       some ext4 macro-instructions depend on its value
3493          */
3494         es = (struct ext4_super_block *) (bh->b_data + offset);
3495         sbi->s_es = es;
3496         sb->s_magic = le16_to_cpu(es->s_magic);
3497         if (sb->s_magic != EXT4_SUPER_MAGIC)
3498                 goto cantfind_ext4;
3499         sbi->s_kbytes_written = le64_to_cpu(es->s_kbytes_written);
3500
3501         /* Warn if metadata_csum and gdt_csum are both set. */
3502         if (ext4_has_feature_metadata_csum(sb) &&
3503             ext4_has_feature_gdt_csum(sb))
3504                 ext4_warning(sb, "metadata_csum and uninit_bg are "
3505                              "redundant flags; please run fsck.");
3506
3507         /* Check for a known checksum algorithm */
3508         if (!ext4_verify_csum_type(sb, es)) {
3509                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3510                          "unknown checksum algorithm.");
3511                 silent = 1;
3512                 goto cantfind_ext4;
3513         }
3514
3515         /* Load the checksum driver */
3516         if (ext4_has_feature_metadata_csum(sb)) {
3517                 sbi->s_chksum_driver = crypto_alloc_shash("crc32c", 0, 0);
3518                 if (IS_ERR(sbi->s_chksum_driver)) {
3519                         ext4_msg(sb, KERN_ERR, "Cannot load crc32c driver.");
3520                         ret = PTR_ERR(sbi->s_chksum_driver);
3521                         sbi->s_chksum_driver = NULL;
3522                         goto failed_mount;
3523                 }
3524         }
3525
3526         /* Check superblock checksum */
3527         if (!ext4_superblock_csum_verify(sb, es)) {
3528                 ext4_msg(sb, KERN_ERR, "VFS: Found ext4 filesystem with "
3529                          "invalid superblock checksum.  Run e2fsck?");
3530                 silent = 1;
3531                 ret = -EFSBADCRC;
3532                 goto cantfind_ext4;
3533         }
3534
3535         /* Precompute checksum seed for all metadata */
3536         if (ext4_has_feature_csum_seed(sb))
3537                 sbi->s_csum_seed = le32_to_cpu(es->s_checksum_seed);
3538         else if (ext4_has_metadata_csum(sb))
3539                 sbi->s_csum_seed = ext4_chksum(sbi, ~0, es->s_uuid,
3540                                                sizeof(es->s_uuid));
3541
3542         /* Set defaults before we parse the mount options */
3543         def_mount_opts = le32_to_cpu(es->s_default_mount_opts);
3544         set_opt(sb, INIT_INODE_TABLE);
3545         if (def_mount_opts & EXT4_DEFM_DEBUG)
3546                 set_opt(sb, DEBUG);
3547         if (def_mount_opts & EXT4_DEFM_BSDGROUPS)
3548                 set_opt(sb, GRPID);
3549         if (def_mount_opts & EXT4_DEFM_UID16)
3550                 set_opt(sb, NO_UID32);
3551         /* xattr user namespace & acls are now defaulted on */
3552         set_opt(sb, XATTR_USER);
3553 #ifdef CONFIG_EXT4_FS_POSIX_ACL
3554         set_opt(sb, POSIX_ACL);
3555 #endif
3556         /* don't forget to enable journal_csum when metadata_csum is enabled. */
3557         if (ext4_has_metadata_csum(sb))
3558                 set_opt(sb, JOURNAL_CHECKSUM);
3559
3560         if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_DATA)
3561                 set_opt(sb, JOURNAL_DATA);
3562         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_ORDERED)
3563                 set_opt(sb, ORDERED_DATA);
3564         else if ((def_mount_opts & EXT4_DEFM_JMODE) == EXT4_DEFM_JMODE_WBACK)
3565                 set_opt(sb, WRITEBACK_DATA);
3566
3567         if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_PANIC)
3568                 set_opt(sb, ERRORS_PANIC);
3569         else if (le16_to_cpu(sbi->s_es->s_errors) == EXT4_ERRORS_CONTINUE)
3570                 set_opt(sb, ERRORS_CONT);
3571         else
3572                 set_opt(sb, ERRORS_RO);
3573         /* block_validity enabled by default; disable with noblock_validity */
3574         set_opt(sb, BLOCK_VALIDITY);
3575         if (def_mount_opts & EXT4_DEFM_DISCARD)
3576                 set_opt(sb, DISCARD);
3577
3578         sbi->s_resuid = make_kuid(&init_user_ns, le16_to_cpu(es->s_def_resuid));
3579         sbi->s_resgid = make_kgid(&init_user_ns, le16_to_cpu(es->s_def_resgid));
3580         sbi->s_commit_interval = JBD2_DEFAULT_MAX_COMMIT_AGE * HZ;
3581         sbi->s_min_batch_time = EXT4_DEF_MIN_BATCH_TIME;
3582         sbi->s_max_batch_time = EXT4_DEF_MAX_BATCH_TIME;
3583
3584         if ((def_mount_opts & EXT4_DEFM_NOBARRIER) == 0)
3585                 set_opt(sb, BARRIER);
3586
3587         /*
3588          * enable delayed allocation by default
3589          * Use -o nodelalloc to turn it off
3590          */
3591         if (!IS_EXT3_SB(sb) && !IS_EXT2_SB(sb) &&
3592             ((def_mount_opts & EXT4_DEFM_NODELALLOC) == 0))
3593                 set_opt(sb, DELALLOC);
3594
3595         /*
3596          * set default s_li_wait_mult for lazyinit, for the case there is
3597          * no mount option specified.
3598          */
3599         sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
3600
3601         if (sbi->s_es->s_mount_opts[0]) {
3602                 char *s_mount_opts = kstrndup(sbi->s_es->s_mount_opts,
3603                                               sizeof(sbi->s_es->s_mount_opts),
3604                                               GFP_KERNEL);
3605                 if (!s_mount_opts)
3606                         goto failed_mount;
3607                 if (!parse_options(s_mount_opts, sb, &journal_devnum,
3608                                    &journal_ioprio, 0)) {
3609                         ext4_msg(sb, KERN_WARNING,
3610                                  "failed to parse options in superblock: %s",
3611                                  s_mount_opts);
3612                 }
3613                 kfree(s_mount_opts);
3614         }
3615         sbi->s_def_mount_opt = sbi->s_mount_opt;
3616         if (!parse_options((char *) data, sb, &journal_devnum,
3617                            &journal_ioprio, 0))
3618                 goto failed_mount;
3619
3620         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
3621                 printk_once(KERN_WARNING "EXT4-fs: Warning: mounting "
3622                             "with data=journal disables delayed "
3623                             "allocation and O_DIRECT support!\n");
3624                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
3625                         ext4_msg(sb, KERN_ERR, "can't mount with "
3626                                  "both data=journal and delalloc");
3627                         goto failed_mount;
3628                 }
3629                 if (test_opt(sb, DIOREAD_NOLOCK)) {
3630                         ext4_msg(sb, KERN_ERR, "can't mount with "
3631                                  "both data=journal and dioread_nolock");
3632                         goto failed_mount;
3633                 }
3634                 if (test_opt(sb, DAX)) {
3635                         ext4_msg(sb, KERN_ERR, "can't mount with "
3636                                  "both data=journal and dax");
3637                         goto failed_mount;
3638                 }
3639                 if (ext4_has_feature_encrypt(sb)) {
3640                         ext4_msg(sb, KERN_WARNING,
3641                                  "encrypted files will use data=ordered "
3642                                  "instead of data journaling mode");
3643                 }
3644                 if (test_opt(sb, DELALLOC))
3645                         clear_opt(sb, DELALLOC);
3646         } else {
3647                 sb->s_iflags |= SB_I_CGROUPWB;
3648         }
3649
3650         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
3651                 (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
3652
3653         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV &&
3654             (ext4_has_compat_features(sb) ||
3655              ext4_has_ro_compat_features(sb) ||
3656              ext4_has_incompat_features(sb)))
3657                 ext4_msg(sb, KERN_WARNING,
3658                        "feature flags set on rev 0 fs, "
3659                        "running e2fsck is recommended");
3660
3661         if (es->s_creator_os == cpu_to_le32(EXT4_OS_HURD)) {
3662                 set_opt2(sb, HURD_COMPAT);
3663                 if (ext4_has_feature_64bit(sb)) {
3664                         ext4_msg(sb, KERN_ERR,
3665                                  "The Hurd can't support 64-bit file systems");
3666                         goto failed_mount;
3667                 }
3668         }
3669
3670         if (IS_EXT2_SB(sb)) {
3671                 if (ext2_feature_set_ok(sb))
3672                         ext4_msg(sb, KERN_INFO, "mounting ext2 file system "
3673                                  "using the ext4 subsystem");
3674                 else {
3675                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext2 due "
3676                                  "to feature incompatibilities");
3677                         goto failed_mount;
3678                 }
3679         }
3680
3681         if (IS_EXT3_SB(sb)) {
3682                 if (ext3_feature_set_ok(sb))
3683                         ext4_msg(sb, KERN_INFO, "mounting ext3 file system "
3684                                  "using the ext4 subsystem");
3685                 else {
3686                         ext4_msg(sb, KERN_ERR, "couldn't mount as ext3 due "
3687                                  "to feature incompatibilities");
3688                         goto failed_mount;
3689                 }
3690         }
3691
3692         /*
3693          * Check feature flags regardless of the revision level, since we
3694          * previously didn't change the revision level when setting the flags,
3695          * so there is a chance incompat flags are set on a rev 0 filesystem.
3696          */
3697         if (!ext4_feature_set_ok(sb, (sb->s_flags & MS_RDONLY)))
3698                 goto failed_mount;
3699
3700         blocksize = BLOCK_SIZE << le32_to_cpu(es->s_log_block_size);
3701         if (blocksize < EXT4_MIN_BLOCK_SIZE ||
3702             blocksize > EXT4_MAX_BLOCK_SIZE) {
3703                 ext4_msg(sb, KERN_ERR,
3704                        "Unsupported filesystem blocksize %d (%d log_block_size)",
3705                          blocksize, le32_to_cpu(es->s_log_block_size));
3706                 goto failed_mount;
3707         }
3708         if (le32_to_cpu(es->s_log_block_size) >
3709             (EXT4_MAX_BLOCK_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
3710                 ext4_msg(sb, KERN_ERR,
3711                          "Invalid log block size: %u",
3712                          le32_to_cpu(es->s_log_block_size));
3713                 goto failed_mount;
3714         }
3715         if (le32_to_cpu(es->s_log_cluster_size) >
3716             (EXT4_MAX_CLUSTER_LOG_SIZE - EXT4_MIN_BLOCK_LOG_SIZE)) {
3717                 ext4_msg(sb, KERN_ERR,
3718                          "Invalid log cluster size: %u",
3719                          le32_to_cpu(es->s_log_cluster_size));
3720                 goto failed_mount;
3721         }
3722
3723         if (le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks) > (blocksize / 4)) {
3724                 ext4_msg(sb, KERN_ERR,
3725                          "Number of reserved GDT blocks insanely large: %d",
3726                          le16_to_cpu(sbi->s_es->s_reserved_gdt_blocks));
3727                 goto failed_mount;
3728         }
3729
3730         if (sbi->s_mount_opt & EXT4_MOUNT_DAX) {
3731                 err = bdev_dax_supported(sb, blocksize);
3732                 if (err)
3733                         goto failed_mount;
3734         }
3735
3736         if (ext4_has_feature_encrypt(sb) && es->s_encryption_level) {
3737                 ext4_msg(sb, KERN_ERR, "Unsupported encryption level %d",
3738                          es->s_encryption_level);
3739                 goto failed_mount;
3740         }
3741
3742         if (sb->s_blocksize != blocksize) {
3743                 /* Validate the filesystem blocksize */
3744                 if (!sb_set_blocksize(sb, blocksize)) {
3745                         ext4_msg(sb, KERN_ERR, "bad block size %d",
3746                                         blocksize);
3747                         goto failed_mount;
3748                 }
3749
3750                 brelse(bh);
3751                 logical_sb_block = sb_block * EXT4_MIN_BLOCK_SIZE;
3752                 offset = do_div(logical_sb_block, blocksize);
3753                 bh = sb_bread_unmovable(sb, logical_sb_block);
3754                 if (!bh) {
3755                         ext4_msg(sb, KERN_ERR,
3756                                "Can't read superblock on 2nd try");
3757                         goto failed_mount;
3758                 }
3759                 es = (struct ext4_super_block *)(bh->b_data + offset);
3760                 sbi->s_es = es;
3761                 if (es->s_magic != cpu_to_le16(EXT4_SUPER_MAGIC)) {
3762                         ext4_msg(sb, KERN_ERR,
3763                                "Magic mismatch, very weird!");
3764                         goto failed_mount;
3765                 }
3766         }
3767
3768         has_huge_files = ext4_has_feature_huge_file(sb);
3769         sbi->s_bitmap_maxbytes = ext4_max_bitmap_size(sb->s_blocksize_bits,
3770                                                       has_huge_files);
3771         sb->s_maxbytes = ext4_max_size(sb->s_blocksize_bits, has_huge_files);
3772
3773         if (le32_to_cpu(es->s_rev_level) == EXT4_GOOD_OLD_REV) {
3774                 sbi->s_inode_size = EXT4_GOOD_OLD_INODE_SIZE;
3775                 sbi->s_first_ino = EXT4_GOOD_OLD_FIRST_INO;
3776         } else {
3777                 sbi->s_inode_size = le16_to_cpu(es->s_inode_size);
3778                 sbi->s_first_ino = le32_to_cpu(es->s_first_ino);
3779                 if (sbi->s_first_ino < EXT4_GOOD_OLD_FIRST_INO) {
3780                         ext4_msg(sb, KERN_ERR, "invalid first ino: %u",
3781                                  sbi->s_first_ino);
3782                         goto failed_mount;
3783                 }
3784                 if ((sbi->s_inode_size < EXT4_GOOD_OLD_INODE_SIZE) ||
3785                     (!is_power_of_2(sbi->s_inode_size)) ||
3786                     (sbi->s_inode_size > blocksize)) {
3787                         ext4_msg(sb, KERN_ERR,
3788                                "unsupported inode size: %d",
3789                                sbi->s_inode_size);
3790                         goto failed_mount;
3791                 }
3792                 if (sbi->s_inode_size > EXT4_GOOD_OLD_INODE_SIZE)
3793                         sb->s_time_gran = 1 << (EXT4_EPOCH_BITS - 2);
3794         }
3795
3796         sbi->s_desc_size = le16_to_cpu(es->s_desc_size);
3797         if (ext4_has_feature_64bit(sb)) {
3798                 if (sbi->s_desc_size < EXT4_MIN_DESC_SIZE_64BIT ||
3799                     sbi->s_desc_size > EXT4_MAX_DESC_SIZE ||
3800                     !is_power_of_2(sbi->s_desc_size)) {
3801                         ext4_msg(sb, KERN_ERR,
3802                                "unsupported descriptor size %lu",
3803                                sbi->s_desc_size);
3804                         goto failed_mount;
3805                 }
3806         } else
3807                 sbi->s_desc_size = EXT4_MIN_DESC_SIZE;
3808
3809         sbi->s_blocks_per_group = le32_to_cpu(es->s_blocks_per_group);
3810         sbi->s_inodes_per_group = le32_to_cpu(es->s_inodes_per_group);
3811
3812         sbi->s_inodes_per_block = blocksize / EXT4_INODE_SIZE(sb);
3813         if (sbi->s_inodes_per_block == 0)
3814                 goto cantfind_ext4;
3815         if (sbi->s_inodes_per_group < sbi->s_inodes_per_block ||
3816             sbi->s_inodes_per_group > blocksize * 8) {
3817                 ext4_msg(sb, KERN_ERR, "invalid inodes per group: %lu\n",
3818                          sbi->s_inodes_per_group);
3819                 goto failed_mount;
3820         }
3821         sbi->s_itb_per_group = sbi->s_inodes_per_group /
3822                                         sbi->s_inodes_per_block;
3823         sbi->s_desc_per_block = blocksize / EXT4_DESC_SIZE(sb);
3824         sbi->s_sbh = bh;
3825         sbi->s_mount_state = le16_to_cpu(es->s_state);
3826         sbi->s_addr_per_block_bits = ilog2(EXT4_ADDR_PER_BLOCK(sb));
3827         sbi->s_desc_per_block_bits = ilog2(EXT4_DESC_PER_BLOCK(sb));
3828
3829         for (i = 0; i < 4; i++)
3830                 sbi->s_hash_seed[i] = le32_to_cpu(es->s_hash_seed[i]);
3831         sbi->s_def_hash_version = es->s_def_hash_version;
3832         if (ext4_has_feature_dir_index(sb)) {
3833                 i = le32_to_cpu(es->s_flags);
3834                 if (i & EXT2_FLAGS_UNSIGNED_HASH)
3835                         sbi->s_hash_unsigned = 3;
3836                 else if ((i & EXT2_FLAGS_SIGNED_HASH) == 0) {
3837 #ifdef __CHAR_UNSIGNED__
3838                         if (!(sb->s_flags & MS_RDONLY))
3839                                 es->s_flags |=
3840                                         cpu_to_le32(EXT2_FLAGS_UNSIGNED_HASH);
3841                         sbi->s_hash_unsigned = 3;
3842 #else
3843                         if (!(sb->s_flags & MS_RDONLY))
3844                                 es->s_flags |=
3845                                         cpu_to_le32(EXT2_FLAGS_SIGNED_HASH);
3846 #endif
3847                 }
3848         }
3849
3850         /* Handle clustersize */
3851         clustersize = BLOCK_SIZE << le32_to_cpu(es->s_log_cluster_size);
3852         has_bigalloc = ext4_has_feature_bigalloc(sb);
3853         if (has_bigalloc) {
3854                 if (clustersize < blocksize) {
3855                         ext4_msg(sb, KERN_ERR,
3856                                  "cluster size (%d) smaller than "
3857                                  "block size (%d)", clustersize, blocksize);
3858                         goto failed_mount;
3859                 }
3860                 sbi->s_cluster_bits = le32_to_cpu(es->s_log_cluster_size) -
3861                         le32_to_cpu(es->s_log_block_size);
3862                 sbi->s_clusters_per_group =
3863                         le32_to_cpu(es->s_clusters_per_group);
3864                 if (sbi->s_clusters_per_group > blocksize * 8) {
3865                         ext4_msg(sb, KERN_ERR,
3866                                  "#clusters per group too big: %lu",
3867                                  sbi->s_clusters_per_group);
3868                         goto failed_mount;
3869                 }
3870                 if (sbi->s_blocks_per_group !=
3871                     (sbi->s_clusters_per_group * (clustersize / blocksize))) {
3872                         ext4_msg(sb, KERN_ERR, "blocks per group (%lu) and "
3873                                  "clusters per group (%lu) inconsistent",
3874                                  sbi->s_blocks_per_group,
3875                                  sbi->s_clusters_per_group);
3876                         goto failed_mount;
3877                 }
3878         } else {
3879                 if (clustersize != blocksize) {
3880                         ext4_msg(sb, KERN_ERR,
3881                                  "fragment/cluster size (%d) != "
3882                                  "block size (%d)", clustersize, blocksize);
3883                         goto failed_mount;
3884                 }
3885                 if (sbi->s_blocks_per_group > blocksize * 8) {
3886                         ext4_msg(sb, KERN_ERR,
3887                                  "#blocks per group too big: %lu",
3888                                  sbi->s_blocks_per_group);
3889                         goto failed_mount;
3890                 }
3891                 sbi->s_clusters_per_group = sbi->s_blocks_per_group;
3892                 sbi->s_cluster_bits = 0;
3893         }
3894         sbi->s_cluster_ratio = clustersize / blocksize;
3895
3896         /* Do we have standard group size of clustersize * 8 blocks ? */
3897         if (sbi->s_blocks_per_group == clustersize << 3)
3898                 set_opt2(sb, STD_GROUP_SIZE);
3899
3900         /*
3901          * Test whether we have more sectors than will fit in sector_t,
3902          * and whether the max offset is addressable by the page cache.
3903          */
3904         err = generic_check_addressable(sb->s_blocksize_bits,
3905                                         ext4_blocks_count(es));
3906         if (err) {
3907                 ext4_msg(sb, KERN_ERR, "filesystem"
3908                          " too large to mount safely on this system");
3909                 if (sizeof(sector_t) < 8)
3910                         ext4_msg(sb, KERN_WARNING, "CONFIG_LBDAF not enabled");
3911                 goto failed_mount;
3912         }
3913
3914         if (EXT4_BLOCKS_PER_GROUP(sb) == 0)
3915                 goto cantfind_ext4;
3916
3917         /* check blocks count against device size */
3918         blocks_count = sb->s_bdev->bd_inode->i_size >> sb->s_blocksize_bits;
3919         if (blocks_count && ext4_blocks_count(es) > blocks_count) {
3920                 ext4_msg(sb, KERN_WARNING, "bad geometry: block count %llu "
3921                        "exceeds size of device (%llu blocks)",
3922                        ext4_blocks_count(es), blocks_count);
3923                 goto failed_mount;
3924         }
3925
3926         /*
3927          * It makes no sense for the first data block to be beyond the end
3928          * of the filesystem.
3929          */
3930         if (le32_to_cpu(es->s_first_data_block) >= ext4_blocks_count(es)) {
3931                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
3932                          "block %u is beyond end of filesystem (%llu)",
3933                          le32_to_cpu(es->s_first_data_block),
3934                          ext4_blocks_count(es));
3935                 goto failed_mount;
3936         }
3937         if ((es->s_first_data_block == 0) && (es->s_log_block_size == 0) &&
3938             (sbi->s_cluster_ratio == 1)) {
3939                 ext4_msg(sb, KERN_WARNING, "bad geometry: first data "
3940                          "block is 0 with a 1k block and cluster size");
3941                 goto failed_mount;
3942         }
3943
3944         blocks_count = (ext4_blocks_count(es) -
3945                         le32_to_cpu(es->s_first_data_block) +
3946                         EXT4_BLOCKS_PER_GROUP(sb) - 1);
3947         do_div(blocks_count, EXT4_BLOCKS_PER_GROUP(sb));
3948         if (blocks_count > ((uint64_t)1<<32) - EXT4_DESC_PER_BLOCK(sb)) {
3949                 ext4_msg(sb, KERN_WARNING, "groups count too large: %llu "
3950                        "(block count %llu, first data block %u, "
3951                        "blocks per group %lu)", blocks_count,
3952                        ext4_blocks_count(es),
3953                        le32_to_cpu(es->s_first_data_block),
3954                        EXT4_BLOCKS_PER_GROUP(sb));
3955                 goto failed_mount;
3956         }
3957         sbi->s_groups_count = blocks_count;
3958         sbi->s_blockfile_groups = min_t(ext4_group_t, sbi->s_groups_count,
3959                         (EXT4_MAX_BLOCK_FILE_PHYS / EXT4_BLOCKS_PER_GROUP(sb)));
3960         if (((u64)sbi->s_groups_count * sbi->s_inodes_per_group) !=
3961             le32_to_cpu(es->s_inodes_count)) {
3962                 ext4_msg(sb, KERN_ERR, "inodes count not valid: %u vs %llu",
3963                          le32_to_cpu(es->s_inodes_count),
3964                          ((u64)sbi->s_groups_count * sbi->s_inodes_per_group));
3965                 ret = -EINVAL;
3966                 goto failed_mount;
3967         }
3968         db_count = (sbi->s_groups_count + EXT4_DESC_PER_BLOCK(sb) - 1) /
3969                    EXT4_DESC_PER_BLOCK(sb);
3970         if (ext4_has_feature_meta_bg(sb)) {
3971                 if (le32_to_cpu(es->s_first_meta_bg) > db_count) {
3972                         ext4_msg(sb, KERN_WARNING,
3973                                  "first meta block group too large: %u "
3974                                  "(group descriptor block count %u)",
3975                                  le32_to_cpu(es->s_first_meta_bg), db_count);
3976                         goto failed_mount;
3977                 }
3978         }
3979         rcu_assign_pointer(sbi->s_group_desc,
3980                            ext4_kvmalloc(db_count *
3981                                           sizeof(struct buffer_head *),
3982                                           GFP_KERNEL));
3983         if (sbi->s_group_desc == NULL) {
3984                 ext4_msg(sb, KERN_ERR, "not enough memory");
3985                 ret = -ENOMEM;
3986                 goto failed_mount;
3987         }
3988
3989         bgl_lock_init(sbi->s_blockgroup_lock);
3990
3991         for (i = 0; i < db_count; i++) {
3992                 struct buffer_head *bh;
3993
3994                 block = descriptor_loc(sb, logical_sb_block, i);
3995                 bh = sb_bread_unmovable(sb, block);
3996                 if (!bh) {
3997                         ext4_msg(sb, KERN_ERR,
3998                                "can't read group descriptor %d", i);
3999                         db_count = i;
4000                         goto failed_mount2;
4001                 }
4002                 rcu_read_lock();
4003                 rcu_dereference(sbi->s_group_desc)[i] = bh;
4004                 rcu_read_unlock();
4005         }
4006         sbi->s_gdb_count = db_count;
4007         if (!ext4_check_descriptors(sb, logical_sb_block, &first_not_zeroed)) {
4008                 ext4_msg(sb, KERN_ERR, "group descriptors corrupted!");
4009                 ret = -EFSCORRUPTED;
4010                 goto failed_mount2;
4011         }
4012
4013         get_random_bytes(&sbi->s_next_generation, sizeof(u32));
4014         spin_lock_init(&sbi->s_next_gen_lock);
4015
4016         setup_timer(&sbi->s_err_report, print_daily_error_info,
4017                 (unsigned long) sb);
4018
4019         /* Register extent status tree shrinker */
4020         if (ext4_es_register_shrinker(sbi))
4021                 goto failed_mount3;
4022
4023         sbi->s_stripe = ext4_get_stripe_size(sbi);
4024         sbi->s_extent_max_zeroout_kb = 32;
4025
4026         /*
4027          * set up enough so that it can read an inode
4028          */
4029         sb->s_op = &ext4_sops;
4030         sb->s_export_op = &ext4_export_ops;
4031         sb->s_xattr = ext4_xattr_handlers;
4032         sb->s_cop = &ext4_cryptops;
4033 #ifdef CONFIG_QUOTA
4034         sb->dq_op = &ext4_quota_operations;
4035         if (ext4_has_feature_quota(sb))
4036                 sb->s_qcop = &dquot_quotactl_sysfile_ops;
4037         else
4038                 sb->s_qcop = &ext4_qctl_operations;
4039         sb->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
4040 #endif
4041         memcpy(sb->s_uuid, es->s_uuid, sizeof(es->s_uuid));
4042
4043         INIT_LIST_HEAD(&sbi->s_orphan); /* unlinked but open files */
4044         mutex_init(&sbi->s_orphan_lock);
4045
4046         sb->s_root = NULL;
4047
4048         needs_recovery = (es->s_last_orphan != 0 ||
4049                           ext4_has_feature_journal_needs_recovery(sb));
4050
4051         if (ext4_has_feature_mmp(sb) && !(sb->s_flags & MS_RDONLY))
4052                 if (ext4_multi_mount_protect(sb, le64_to_cpu(es->s_mmp_block)))
4053                         goto failed_mount3a;
4054
4055         /*
4056          * The first inode we look at is the journal inode.  Don't try
4057          * root first: it may be modified in the journal!
4058          */
4059         if (!test_opt(sb, NOLOAD) && ext4_has_feature_journal(sb)) {
4060                 err = ext4_load_journal(sb, es, journal_devnum);
4061                 if (err)
4062                         goto failed_mount3a;
4063         } else if (test_opt(sb, NOLOAD) && !(sb->s_flags & MS_RDONLY) &&
4064                    ext4_has_feature_journal_needs_recovery(sb)) {
4065                 ext4_msg(sb, KERN_ERR, "required journal recovery "
4066                        "suppressed and not mounted read-only");
4067                 goto failed_mount_wq;
4068         } else {
4069                 /* Nojournal mode, all journal mount options are illegal */
4070                 if (test_opt2(sb, EXPLICIT_JOURNAL_CHECKSUM)) {
4071                         ext4_msg(sb, KERN_ERR, "can't mount with "
4072                                  "journal_checksum, fs mounted w/o journal");
4073                         goto failed_mount_wq;
4074                 }
4075                 if (test_opt(sb, JOURNAL_ASYNC_COMMIT)) {
4076                         ext4_msg(sb, KERN_ERR, "can't mount with "
4077                                  "journal_async_commit, fs mounted w/o journal");
4078                         goto failed_mount_wq;
4079                 }
4080                 if (sbi->s_commit_interval != JBD2_DEFAULT_MAX_COMMIT_AGE*HZ) {
4081                         ext4_msg(sb, KERN_ERR, "can't mount with "
4082                                  "commit=%lu, fs mounted w/o journal",
4083                                  sbi->s_commit_interval / HZ);
4084                         goto failed_mount_wq;
4085                 }
4086                 if (EXT4_MOUNT_DATA_FLAGS &
4087                     (sbi->s_mount_opt ^ sbi->s_def_mount_opt)) {
4088                         ext4_msg(sb, KERN_ERR, "can't mount with "
4089                                  "data=, fs mounted w/o journal");
4090                         goto failed_mount_wq;
4091                 }
4092                 sbi->s_def_mount_opt &= ~EXT4_MOUNT_JOURNAL_CHECKSUM;
4093                 clear_opt(sb, JOURNAL_CHECKSUM);
4094                 clear_opt(sb, DATA_FLAGS);
4095                 sbi->s_journal = NULL;
4096                 needs_recovery = 0;
4097                 goto no_journal;
4098         }
4099
4100         if (ext4_has_feature_64bit(sb) &&
4101             !jbd2_journal_set_features(EXT4_SB(sb)->s_journal, 0, 0,
4102                                        JBD2_FEATURE_INCOMPAT_64BIT)) {
4103                 ext4_msg(sb, KERN_ERR, "Failed to set 64-bit journal feature");
4104                 goto failed_mount_wq;
4105         }
4106
4107         if (!set_journal_csum_feature_set(sb)) {
4108                 ext4_msg(sb, KERN_ERR, "Failed to set journal checksum "
4109                          "feature set");
4110                 goto failed_mount_wq;
4111         }
4112
4113         /* We have now updated the journal if required, so we can
4114          * validate the data journaling mode. */
4115         switch (test_opt(sb, DATA_FLAGS)) {
4116         case 0:
4117                 /* No mode set, assume a default based on the journal
4118                  * capabilities: ORDERED_DATA if the journal can
4119                  * cope, else JOURNAL_DATA
4120                  */
4121                 if (jbd2_journal_check_available_features
4122                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE))
4123                         set_opt(sb, ORDERED_DATA);
4124                 else
4125                         set_opt(sb, JOURNAL_DATA);
4126                 break;
4127
4128         case EXT4_MOUNT_ORDERED_DATA:
4129         case EXT4_MOUNT_WRITEBACK_DATA:
4130                 if (!jbd2_journal_check_available_features
4131                     (sbi->s_journal, 0, 0, JBD2_FEATURE_INCOMPAT_REVOKE)) {
4132                         ext4_msg(sb, KERN_ERR, "Journal does not support "
4133                                "requested data journaling mode");
4134                         goto failed_mount_wq;
4135                 }
4136         default:
4137                 break;
4138         }
4139         set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
4140
4141         sbi->s_journal->j_commit_callback = ext4_journal_commit_callback;
4142
4143 no_journal:
4144         sbi->s_mb_cache = ext4_xattr_create_cache();
4145         if (!sbi->s_mb_cache) {
4146                 ext4_msg(sb, KERN_ERR, "Failed to create an mb_cache");
4147                 goto failed_mount_wq;
4148         }
4149
4150         if ((DUMMY_ENCRYPTION_ENABLED(sbi) || ext4_has_feature_encrypt(sb)) &&
4151             (blocksize != PAGE_SIZE)) {
4152                 ext4_msg(sb, KERN_ERR,
4153                          "Unsupported blocksize for fs encryption");
4154                 goto failed_mount_wq;
4155         }
4156
4157         if (DUMMY_ENCRYPTION_ENABLED(sbi) && !(sb->s_flags & MS_RDONLY) &&
4158             !ext4_has_feature_encrypt(sb)) {
4159                 ext4_set_feature_encrypt(sb);
4160                 ext4_commit_super(sb, 1);
4161         }
4162
4163         /*
4164          * Get the # of file system overhead blocks from the
4165          * superblock if present.
4166          */
4167         sbi->s_overhead = le32_to_cpu(es->s_overhead_clusters);
4168         /* ignore the precalculated value if it is ridiculous */
4169         if (sbi->s_overhead > ext4_blocks_count(es))
4170                 sbi->s_overhead = 0;
4171         /*
4172          * If the bigalloc feature is not enabled recalculating the
4173          * overhead doesn't take long, so we might as well just redo
4174          * it to make sure we are using the correct value.
4175          */
4176         if (!ext4_has_feature_bigalloc(sb))
4177                 sbi->s_overhead = 0;
4178         if (sbi->s_overhead == 0) {
4179                 err = ext4_calculate_overhead(sb);
4180                 if (err)
4181                         goto failed_mount_wq;
4182         }
4183
4184         /*
4185          * The maximum number of concurrent works can be high and
4186          * concurrency isn't really necessary.  Limit it to 1.
4187          */
4188         EXT4_SB(sb)->rsv_conversion_wq =
4189                 alloc_workqueue("ext4-rsv-conversion", WQ_MEM_RECLAIM | WQ_UNBOUND, 1);
4190         if (!EXT4_SB(sb)->rsv_conversion_wq) {
4191                 printk(KERN_ERR "EXT4-fs: failed to create workqueue\n");
4192                 ret = -ENOMEM;
4193                 goto failed_mount4;
4194         }
4195
4196         /*
4197          * The jbd2_journal_load will have done any necessary log recovery,
4198          * so we can safely mount the rest of the filesystem now.
4199          */
4200
4201         root = ext4_iget(sb, EXT4_ROOT_INO, EXT4_IGET_SPECIAL);
4202         if (IS_ERR(root)) {
4203                 ext4_msg(sb, KERN_ERR, "get root inode failed");
4204                 ret = PTR_ERR(root);
4205                 root = NULL;
4206                 goto failed_mount4;
4207         }
4208         if (!S_ISDIR(root->i_mode) || !root->i_blocks || !root->i_size) {
4209                 ext4_msg(sb, KERN_ERR, "corrupt root inode, run e2fsck");
4210                 iput(root);
4211                 goto failed_mount4;
4212         }
4213         sb->s_root = d_make_root(root);
4214         if (!sb->s_root) {
4215                 ext4_msg(sb, KERN_ERR, "get root dentry failed");
4216                 ret = -ENOMEM;
4217                 goto failed_mount4;
4218         }
4219
4220         if (ext4_setup_super(sb, es, sb->s_flags & MS_RDONLY))
4221                 sb->s_flags |= MS_RDONLY;
4222
4223         ext4_clamp_want_extra_isize(sb);
4224
4225         ext4_set_resv_clusters(sb);
4226
4227         err = ext4_setup_system_zone(sb);
4228         if (err) {
4229                 ext4_msg(sb, KERN_ERR, "failed to initialize system "
4230                          "zone (%d)", err);
4231                 goto failed_mount4a;
4232         }
4233
4234         ext4_ext_init(sb);
4235         err = ext4_mb_init(sb);
4236         if (err) {
4237                 ext4_msg(sb, KERN_ERR, "failed to initialize mballoc (%d)",
4238                          err);
4239                 goto failed_mount5;
4240         }
4241
4242         block = ext4_count_free_clusters(sb);
4243         ext4_free_blocks_count_set(sbi->s_es,
4244                                    EXT4_C2B(sbi, block));
4245         ext4_superblock_csum_set(sb);
4246         err = percpu_counter_init(&sbi->s_freeclusters_counter, block,
4247                                   GFP_KERNEL);
4248         if (!err) {
4249                 unsigned long freei = ext4_count_free_inodes(sb);
4250                 sbi->s_es->s_free_inodes_count = cpu_to_le32(freei);
4251                 ext4_superblock_csum_set(sb);
4252                 err = percpu_counter_init(&sbi->s_freeinodes_counter, freei,
4253                                           GFP_KERNEL);
4254         }
4255         if (!err)
4256                 err = percpu_counter_init(&sbi->s_dirs_counter,
4257                                           ext4_count_dirs(sb), GFP_KERNEL);
4258         if (!err)
4259                 err = percpu_counter_init(&sbi->s_dirtyclusters_counter, 0,
4260                                           GFP_KERNEL);
4261         if (!err)
4262                 err = percpu_init_rwsem(&sbi->s_writepages_rwsem);
4263
4264         if (err) {
4265                 ext4_msg(sb, KERN_ERR, "insufficient memory");
4266                 goto failed_mount6;
4267         }
4268
4269         if (ext4_has_feature_flex_bg(sb))
4270                 if (!ext4_fill_flex_info(sb)) {
4271                         ext4_msg(sb, KERN_ERR,
4272                                "unable to initialize "
4273                                "flex_bg meta info!");
4274                         goto failed_mount6;
4275                 }
4276
4277         err = ext4_register_li_request(sb, first_not_zeroed);
4278         if (err)
4279                 goto failed_mount6;
4280
4281         err = ext4_register_sysfs(sb);
4282         if (err)
4283                 goto failed_mount7;
4284
4285 #ifdef CONFIG_QUOTA
4286         /* Enable quota usage during mount. */
4287         if (ext4_has_feature_quota(sb) && !(sb->s_flags & MS_RDONLY)) {
4288                 err = ext4_enable_quotas(sb);
4289                 if (err)
4290                         goto failed_mount8;
4291         }
4292 #endif  /* CONFIG_QUOTA */
4293
4294         EXT4_SB(sb)->s_mount_state |= EXT4_ORPHAN_FS;
4295         ext4_orphan_cleanup(sb, es);
4296         EXT4_SB(sb)->s_mount_state &= ~EXT4_ORPHAN_FS;
4297         if (needs_recovery) {
4298                 ext4_msg(sb, KERN_INFO, "recovery complete");
4299                 ext4_mark_recovery_complete(sb, es);
4300         }
4301         if (EXT4_SB(sb)->s_journal) {
4302                 if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA)
4303                         descr = " journalled data mode";
4304                 else if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_ORDERED_DATA)
4305                         descr = " ordered data mode";
4306                 else
4307                         descr = " writeback data mode";
4308         } else
4309                 descr = "out journal";
4310
4311         if (test_opt(sb, DISCARD)) {
4312                 struct request_queue *q = bdev_get_queue(sb->s_bdev);
4313                 if (!blk_queue_discard(q))
4314                         ext4_msg(sb, KERN_WARNING,
4315                                  "mounting with \"discard\" option, but "
4316                                  "the device does not support discard");
4317         }
4318
4319         if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
4320                 ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
4321                          "Opts: %.*s%s%s", descr,
4322                          (int) sizeof(sbi->s_es->s_mount_opts),
4323                          sbi->s_es->s_mount_opts,
4324                          *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
4325
4326         if (es->s_error_count)
4327                 mod_timer(&sbi->s_err_report, jiffies + 300*HZ); /* 5 minutes */
4328
4329         /* Enable message ratelimiting. Default is 10 messages per 5 secs. */
4330         ratelimit_state_init(&sbi->s_err_ratelimit_state, 5 * HZ, 10);
4331         ratelimit_state_init(&sbi->s_warning_ratelimit_state, 5 * HZ, 10);
4332         ratelimit_state_init(&sbi->s_msg_ratelimit_state, 5 * HZ, 10);
4333
4334         kfree(orig_data);
4335 #ifdef CONFIG_EXT4_FS_ENCRYPTION
4336         memcpy(sbi->key_prefix, EXT4_KEY_DESC_PREFIX,
4337                                 EXT4_KEY_DESC_PREFIX_SIZE);
4338         sbi->key_prefix_size = EXT4_KEY_DESC_PREFIX_SIZE;
4339 #endif
4340         return 0;
4341
4342 cantfind_ext4:
4343         if (!silent)
4344                 ext4_msg(sb, KERN_ERR, "VFS: Can't find ext4 filesystem");
4345         goto failed_mount;
4346
4347 #ifdef CONFIG_QUOTA
4348 failed_mount8:
4349         ext4_unregister_sysfs(sb);
4350         kobject_put(&sbi->s_kobj);
4351 #endif
4352 failed_mount7:
4353         ext4_unregister_li_request(sb);
4354 failed_mount6:
4355         ext4_mb_release(sb);
4356         rcu_read_lock();
4357         flex_groups = rcu_dereference(sbi->s_flex_groups);
4358         if (flex_groups) {
4359                 for (i = 0; i < sbi->s_flex_groups_allocated; i++)
4360                         kvfree(flex_groups[i]);
4361                 kvfree(flex_groups);
4362         }
4363         rcu_read_unlock();
4364         percpu_counter_destroy(&sbi->s_freeclusters_counter);
4365         percpu_counter_destroy(&sbi->s_freeinodes_counter);
4366         percpu_counter_destroy(&sbi->s_dirs_counter);
4367         percpu_counter_destroy(&sbi->s_dirtyclusters_counter);
4368         percpu_free_rwsem(&sbi->s_writepages_rwsem);
4369 failed_mount5:
4370         ext4_ext_release(sb);
4371         ext4_release_system_zone(sb);
4372 failed_mount4a:
4373         dput(sb->s_root);
4374         sb->s_root = NULL;
4375 failed_mount4:
4376         ext4_msg(sb, KERN_ERR, "mount failed");
4377         if (EXT4_SB(sb)->rsv_conversion_wq)
4378                 destroy_workqueue(EXT4_SB(sb)->rsv_conversion_wq);
4379 failed_mount_wq:
4380         if (sbi->s_mb_cache) {
4381                 ext4_xattr_destroy_cache(sbi->s_mb_cache);
4382                 sbi->s_mb_cache = NULL;
4383         }
4384         if (sbi->s_journal) {
4385                 jbd2_journal_destroy(sbi->s_journal);
4386                 sbi->s_journal = NULL;
4387         }
4388 failed_mount3a:
4389         ext4_es_unregister_shrinker(sbi);
4390 failed_mount3:
4391         del_timer_sync(&sbi->s_err_report);
4392         if (sbi->s_mmp_tsk)
4393                 kthread_stop(sbi->s_mmp_tsk);
4394 failed_mount2:
4395         rcu_read_lock();
4396         group_desc = rcu_dereference(sbi->s_group_desc);
4397         for (i = 0; i < db_count; i++)
4398                 brelse(group_desc[i]);
4399         kvfree(group_desc);
4400         rcu_read_unlock();
4401 failed_mount:
4402         if (sbi->s_chksum_driver)
4403                 crypto_free_shash(sbi->s_chksum_driver);
4404 #ifdef CONFIG_QUOTA
4405         for (i = 0; i < EXT4_MAXQUOTAS; i++)
4406                 kfree(sbi->s_qf_names[i]);
4407 #endif
4408         ext4_blkdev_remove(sbi);
4409         brelse(bh);
4410 out_fail:
4411         sb->s_fs_info = NULL;
4412         kfree(sbi->s_blockgroup_lock);
4413 out_free_base:
4414         kfree(sbi);
4415         kfree(orig_data);
4416         return err ? err : ret;
4417 }
4418
4419 /*
4420  * Setup any per-fs journal parameters now.  We'll do this both on
4421  * initial mount, once the journal has been initialised but before we've
4422  * done any recovery; and again on any subsequent remount.
4423  */
4424 static void ext4_init_journal_params(struct super_block *sb, journal_t *journal)
4425 {
4426         struct ext4_sb_info *sbi = EXT4_SB(sb);
4427
4428         journal->j_commit_interval = sbi->s_commit_interval;
4429         journal->j_min_batch_time = sbi->s_min_batch_time;
4430         journal->j_max_batch_time = sbi->s_max_batch_time;
4431
4432         write_lock(&journal->j_state_lock);
4433         if (test_opt(sb, BARRIER))
4434                 journal->j_flags |= JBD2_BARRIER;
4435         else
4436                 journal->j_flags &= ~JBD2_BARRIER;
4437         if (test_opt(sb, DATA_ERR_ABORT))
4438                 journal->j_flags |= JBD2_ABORT_ON_SYNCDATA_ERR;
4439         else
4440                 journal->j_flags &= ~JBD2_ABORT_ON_SYNCDATA_ERR;
4441         write_unlock(&journal->j_state_lock);
4442 }
4443
4444 static struct inode *ext4_get_journal_inode(struct super_block *sb,
4445                                              unsigned int journal_inum)
4446 {
4447         struct inode *journal_inode;
4448
4449         /*
4450          * Test for the existence of a valid inode on disk.  Bad things
4451          * happen if we iget() an unused inode, as the subsequent iput()
4452          * will try to delete it.
4453          */
4454         journal_inode = ext4_iget(sb, journal_inum, EXT4_IGET_SPECIAL);
4455         if (IS_ERR(journal_inode)) {
4456                 ext4_msg(sb, KERN_ERR, "no journal found");
4457                 return NULL;
4458         }
4459         if (!journal_inode->i_nlink) {
4460                 make_bad_inode(journal_inode);
4461                 iput(journal_inode);
4462                 ext4_msg(sb, KERN_ERR, "journal inode is deleted");
4463                 return NULL;
4464         }
4465
4466         jbd_debug(2, "Journal inode found at %p: %lld bytes\n",
4467                   journal_inode, journal_inode->i_size);
4468         if (!S_ISREG(journal_inode->i_mode)) {
4469                 ext4_msg(sb, KERN_ERR, "invalid journal inode");
4470                 iput(journal_inode);
4471                 return NULL;
4472         }
4473         return journal_inode;
4474 }
4475
4476 static journal_t *ext4_get_journal(struct super_block *sb,
4477                                    unsigned int journal_inum)
4478 {
4479         struct inode *journal_inode;
4480         journal_t *journal;
4481
4482         BUG_ON(!ext4_has_feature_journal(sb));
4483
4484         journal_inode = ext4_get_journal_inode(sb, journal_inum);
4485         if (!journal_inode)
4486                 return NULL;
4487
4488         journal = jbd2_journal_init_inode(journal_inode);
4489         if (!journal) {
4490                 ext4_msg(sb, KERN_ERR, "Could not load journal inode");
4491                 iput(journal_inode);
4492                 return NULL;
4493         }
4494         journal->j_private = sb;
4495         ext4_init_journal_params(sb, journal);
4496         return journal;
4497 }
4498
4499 static journal_t *ext4_get_dev_journal(struct super_block *sb,
4500                                        dev_t j_dev)
4501 {
4502         struct buffer_head *bh;
4503         journal_t *journal;
4504         ext4_fsblk_t start;
4505         ext4_fsblk_t len;
4506         int hblock, blocksize;
4507         ext4_fsblk_t sb_block;
4508         unsigned long offset;
4509         struct ext4_super_block *es;
4510         struct block_device *bdev;
4511
4512         BUG_ON(!ext4_has_feature_journal(sb));
4513
4514         bdev = ext4_blkdev_get(j_dev, sb);
4515         if (bdev == NULL)
4516                 return NULL;
4517
4518         blocksize = sb->s_blocksize;
4519         hblock = bdev_logical_block_size(bdev);
4520         if (blocksize < hblock) {
4521                 ext4_msg(sb, KERN_ERR,
4522                         "blocksize too small for journal device");
4523                 goto out_bdev;
4524         }
4525
4526         sb_block = EXT4_MIN_BLOCK_SIZE / blocksize;
4527         offset = EXT4_MIN_BLOCK_SIZE % blocksize;
4528         set_blocksize(bdev, blocksize);
4529         if (!(bh = __bread(bdev, sb_block, blocksize))) {
4530                 ext4_msg(sb, KERN_ERR, "couldn't read superblock of "
4531                        "external journal");
4532                 goto out_bdev;
4533         }
4534
4535         es = (struct ext4_super_block *) (bh->b_data + offset);
4536         if ((le16_to_cpu(es->s_magic) != EXT4_SUPER_MAGIC) ||
4537             !(le32_to_cpu(es->s_feature_incompat) &
4538               EXT4_FEATURE_INCOMPAT_JOURNAL_DEV)) {
4539                 ext4_msg(sb, KERN_ERR, "external journal has "
4540                                         "bad superblock");
4541                 brelse(bh);
4542                 goto out_bdev;
4543         }
4544
4545         if ((le32_to_cpu(es->s_feature_ro_compat) &
4546              EXT4_FEATURE_RO_COMPAT_METADATA_CSUM) &&
4547             es->s_checksum != ext4_superblock_csum(sb, es)) {
4548                 ext4_msg(sb, KERN_ERR, "external journal has "
4549                                        "corrupt superblock");
4550                 brelse(bh);
4551                 goto out_bdev;
4552         }
4553
4554         if (memcmp(EXT4_SB(sb)->s_es->s_journal_uuid, es->s_uuid, 16)) {
4555                 ext4_msg(sb, KERN_ERR, "journal UUID does not match");
4556                 brelse(bh);
4557                 goto out_bdev;
4558         }
4559
4560         len = ext4_blocks_count(es);
4561         start = sb_block + 1;
4562         brelse(bh);     /* we're done with the superblock */
4563
4564         journal = jbd2_journal_init_dev(bdev, sb->s_bdev,
4565                                         start, len, blocksize);
4566         if (!journal) {
4567                 ext4_msg(sb, KERN_ERR, "failed to create device journal");
4568                 goto out_bdev;
4569         }
4570         journal->j_private = sb;
4571         ll_rw_block(REQ_OP_READ, REQ_META | REQ_PRIO, 1, &journal->j_sb_buffer);
4572         wait_on_buffer(journal->j_sb_buffer);
4573         if (!buffer_uptodate(journal->j_sb_buffer)) {
4574                 ext4_msg(sb, KERN_ERR, "I/O error on journal device");
4575                 goto out_journal;
4576         }
4577         if (be32_to_cpu(journal->j_superblock->s_nr_users) != 1) {
4578                 ext4_msg(sb, KERN_ERR, "External journal has more than one "
4579                                         "user (unsupported) - %d",
4580                         be32_to_cpu(journal->j_superblock->s_nr_users));
4581                 goto out_journal;
4582         }
4583         EXT4_SB(sb)->journal_bdev = bdev;
4584         ext4_init_journal_params(sb, journal);
4585         return journal;
4586
4587 out_journal:
4588         jbd2_journal_destroy(journal);
4589 out_bdev:
4590         ext4_blkdev_put(bdev);
4591         return NULL;
4592 }
4593
4594 static int ext4_load_journal(struct super_block *sb,
4595                              struct ext4_super_block *es,
4596                              unsigned long journal_devnum)
4597 {
4598         journal_t *journal;
4599         unsigned int journal_inum = le32_to_cpu(es->s_journal_inum);
4600         dev_t journal_dev;
4601         int err = 0;
4602         int really_read_only;
4603
4604         BUG_ON(!ext4_has_feature_journal(sb));
4605
4606         if (journal_devnum &&
4607             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4608                 ext4_msg(sb, KERN_INFO, "external journal device major/minor "
4609                         "numbers have changed");
4610                 journal_dev = new_decode_dev(journal_devnum);
4611         } else
4612                 journal_dev = new_decode_dev(le32_to_cpu(es->s_journal_dev));
4613
4614         really_read_only = bdev_read_only(sb->s_bdev);
4615
4616         /*
4617          * Are we loading a blank journal or performing recovery after a
4618          * crash?  For recovery, we need to check in advance whether we
4619          * can get read-write access to the device.
4620          */
4621         if (ext4_has_feature_journal_needs_recovery(sb)) {
4622                 if (sb->s_flags & MS_RDONLY) {
4623                         ext4_msg(sb, KERN_INFO, "INFO: recovery "
4624                                         "required on readonly filesystem");
4625                         if (really_read_only) {
4626                                 ext4_msg(sb, KERN_ERR, "write access "
4627                                         "unavailable, cannot proceed");
4628                                 return -EROFS;
4629                         }
4630                         ext4_msg(sb, KERN_INFO, "write access will "
4631                                "be enabled during recovery");
4632                 }
4633         }
4634
4635         if (journal_inum && journal_dev) {
4636                 ext4_msg(sb, KERN_ERR, "filesystem has both journal "
4637                        "and inode journals!");
4638                 return -EINVAL;
4639         }
4640
4641         if (journal_inum) {
4642                 if (!(journal = ext4_get_journal(sb, journal_inum)))
4643                         return -EINVAL;
4644         } else {
4645                 if (!(journal = ext4_get_dev_journal(sb, journal_dev)))
4646                         return -EINVAL;
4647         }
4648
4649         if (!(journal->j_flags & JBD2_BARRIER))
4650                 ext4_msg(sb, KERN_INFO, "barriers disabled");
4651
4652         if (!ext4_has_feature_journal_needs_recovery(sb))
4653                 err = jbd2_journal_wipe(journal, !really_read_only);
4654         if (!err) {
4655                 char *save = kmalloc(EXT4_S_ERR_LEN, GFP_KERNEL);
4656                 if (save)
4657                         memcpy(save, ((char *) es) +
4658                                EXT4_S_ERR_START, EXT4_S_ERR_LEN);
4659                 err = jbd2_journal_load(journal);
4660                 if (save)
4661                         memcpy(((char *) es) + EXT4_S_ERR_START,
4662                                save, EXT4_S_ERR_LEN);
4663                 kfree(save);
4664         }
4665
4666         if (err) {
4667                 ext4_msg(sb, KERN_ERR, "error loading journal");
4668                 jbd2_journal_destroy(journal);
4669                 return err;
4670         }
4671
4672         EXT4_SB(sb)->s_journal = journal;
4673         ext4_clear_journal_err(sb, es);
4674
4675         if (!really_read_only && journal_devnum &&
4676             journal_devnum != le32_to_cpu(es->s_journal_dev)) {
4677                 es->s_journal_dev = cpu_to_le32(journal_devnum);
4678
4679                 /* Make sure we flush the recovery flag to disk. */
4680                 ext4_commit_super(sb, 1);
4681         }
4682
4683         return 0;
4684 }
4685
4686 static int ext4_commit_super(struct super_block *sb, int sync)
4687 {
4688         struct ext4_super_block *es = EXT4_SB(sb)->s_es;
4689         struct buffer_head *sbh = EXT4_SB(sb)->s_sbh;
4690         int error = 0;
4691
4692         if (!sbh)
4693                 return -EINVAL;
4694         if (block_device_ejected(sb))
4695                 return -ENODEV;
4696
4697         /*
4698          * If the file system is mounted read-only, don't update the
4699          * superblock write time.  This avoids updating the superblock
4700          * write time when we are mounting the root file system
4701          * read/only but we need to replay the journal; at that point,
4702          * for people who are east of GMT and who make their clock
4703          * tick in localtime for Windows bug-for-bug compatibility,
4704          * the clock is set in the future, and this will cause e2fsck
4705          * to complain and force a full file system check.
4706          */
4707         if (!(sb->s_flags & MS_RDONLY))
4708                 es->s_wtime = cpu_to_le32(get_seconds());
4709         if (sb->s_bdev->bd_part)
4710                 es->s_kbytes_written =
4711                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written +
4712                             ((part_stat_read(sb->s_bdev->bd_part, sectors[1]) -
4713                               EXT4_SB(sb)->s_sectors_written_start) >> 1));
4714         else
4715                 es->s_kbytes_written =
4716                         cpu_to_le64(EXT4_SB(sb)->s_kbytes_written);
4717         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeclusters_counter))
4718                 ext4_free_blocks_count_set(es,
4719                         EXT4_C2B(EXT4_SB(sb), percpu_counter_sum_positive(
4720                                 &EXT4_SB(sb)->s_freeclusters_counter)));
4721         if (percpu_counter_initialized(&EXT4_SB(sb)->s_freeinodes_counter))
4722                 es->s_free_inodes_count =
4723                         cpu_to_le32(percpu_counter_sum_positive(
4724                                 &EXT4_SB(sb)->s_freeinodes_counter));
4725         BUFFER_TRACE(sbh, "marking dirty");
4726         ext4_superblock_csum_set(sb);
4727         if (sync)
4728                 lock_buffer(sbh);
4729         if (buffer_write_io_error(sbh) || !buffer_uptodate(sbh)) {
4730                 /*
4731                  * Oh, dear.  A previous attempt to write the
4732                  * superblock failed.  This could happen because the
4733                  * USB device was yanked out.  Or it could happen to
4734                  * be a transient write error and maybe the block will
4735                  * be remapped.  Nothing we can do but to retry the
4736                  * write and hope for the best.
4737                  */
4738                 ext4_msg(sb, KERN_ERR, "previous I/O error to "
4739                        "superblock detected");
4740                 clear_buffer_write_io_error(sbh);
4741                 set_buffer_uptodate(sbh);
4742         }
4743         mark_buffer_dirty(sbh);
4744         if (sync) {
4745                 unlock_buffer(sbh);
4746                 error = __sync_dirty_buffer(sbh,
4747                         test_opt(sb, BARRIER) ? WRITE_FUA : WRITE_SYNC);
4748                 if (error)
4749                         return error;
4750
4751                 error = buffer_write_io_error(sbh);
4752                 if (error) {
4753                         ext4_msg(sb, KERN_ERR, "I/O error while writing "
4754                                "superblock");
4755                         clear_buffer_write_io_error(sbh);
4756                         set_buffer_uptodate(sbh);
4757                 }
4758         }
4759         return error;
4760 }
4761
4762 /*
4763  * Have we just finished recovery?  If so, and if we are mounting (or
4764  * remounting) the filesystem readonly, then we will end up with a
4765  * consistent fs on disk.  Record that fact.
4766  */
4767 static void ext4_mark_recovery_complete(struct super_block *sb,
4768                                         struct ext4_super_block *es)
4769 {
4770         journal_t *journal = EXT4_SB(sb)->s_journal;
4771
4772         if (!ext4_has_feature_journal(sb)) {
4773                 BUG_ON(journal != NULL);
4774                 return;
4775         }
4776         jbd2_journal_lock_updates(journal);
4777         if (jbd2_journal_flush(journal) < 0)
4778                 goto out;
4779
4780         if (ext4_has_feature_journal_needs_recovery(sb) &&
4781             sb->s_flags & MS_RDONLY) {
4782                 ext4_clear_feature_journal_needs_recovery(sb);
4783                 ext4_commit_super(sb, 1);
4784         }
4785
4786 out:
4787         jbd2_journal_unlock_updates(journal);
4788 }
4789
4790 /*
4791  * If we are mounting (or read-write remounting) a filesystem whose journal
4792  * has recorded an error from a previous lifetime, move that error to the
4793  * main filesystem now.
4794  */
4795 static void ext4_clear_journal_err(struct super_block *sb,
4796                                    struct ext4_super_block *es)
4797 {
4798         journal_t *journal;
4799         int j_errno;
4800         const char *errstr;
4801
4802         BUG_ON(!ext4_has_feature_journal(sb));
4803
4804         journal = EXT4_SB(sb)->s_journal;
4805
4806         /*
4807          * Now check for any error status which may have been recorded in the
4808          * journal by a prior ext4_error() or ext4_abort()
4809          */
4810
4811         j_errno = jbd2_journal_errno(journal);
4812         if (j_errno) {
4813                 char nbuf[16];
4814
4815                 errstr = ext4_decode_error(sb, j_errno, nbuf);
4816                 ext4_warning(sb, "Filesystem error recorded "
4817                              "from previous mount: %s", errstr);
4818                 ext4_warning(sb, "Marking fs in need of filesystem check.");
4819
4820                 EXT4_SB(sb)->s_mount_state |= EXT4_ERROR_FS;
4821                 es->s_state |= cpu_to_le16(EXT4_ERROR_FS);
4822                 ext4_commit_super(sb, 1);
4823
4824                 jbd2_journal_clear_err(journal);
4825                 jbd2_journal_update_sb_errno(journal);
4826         }
4827 }
4828
4829 /*
4830  * Force the running and committing transactions to commit,
4831  * and wait on the commit.
4832  */
4833 int ext4_force_commit(struct super_block *sb)
4834 {
4835         journal_t *journal;
4836
4837         if (sb->s_flags & MS_RDONLY)
4838                 return 0;
4839
4840         journal = EXT4_SB(sb)->s_journal;
4841         return ext4_journal_force_commit(journal);
4842 }
4843
4844 static int ext4_sync_fs(struct super_block *sb, int wait)
4845 {
4846         int ret = 0;
4847         tid_t target;
4848         bool needs_barrier = false;
4849         struct ext4_sb_info *sbi = EXT4_SB(sb);
4850
4851         trace_ext4_sync_fs(sb, wait);
4852         flush_workqueue(sbi->rsv_conversion_wq);
4853         /*
4854          * Writeback quota in non-journalled quota case - journalled quota has
4855          * no dirty dquots
4856          */
4857         dquot_writeback_dquots(sb, -1);
4858         /*
4859          * Data writeback is possible w/o journal transaction, so barrier must
4860          * being sent at the end of the function. But we can skip it if
4861          * transaction_commit will do it for us.
4862          */
4863         if (sbi->s_journal) {
4864                 target = jbd2_get_latest_transaction(sbi->s_journal);
4865                 if (wait && sbi->s_journal->j_flags & JBD2_BARRIER &&
4866                     !jbd2_trans_will_send_data_barrier(sbi->s_journal, target))
4867                         needs_barrier = true;
4868
4869                 if (jbd2_journal_start_commit(sbi->s_journal, &target)) {
4870                         if (wait)
4871                                 ret = jbd2_log_wait_commit(sbi->s_journal,
4872                                                            target);
4873                 }
4874         } else if (wait && test_opt(sb, BARRIER))
4875                 needs_barrier = true;
4876         if (needs_barrier) {
4877                 int err;
4878                 err = blkdev_issue_flush(sb->s_bdev, GFP_KERNEL, NULL);
4879                 if (!ret)
4880                         ret = err;
4881         }
4882
4883         return ret;
4884 }
4885
4886 /*
4887  * LVM calls this function before a (read-only) snapshot is created.  This
4888  * gives us a chance to flush the journal completely and mark the fs clean.
4889  *
4890  * Note that only this function cannot bring a filesystem to be in a clean
4891  * state independently. It relies on upper layer to stop all data & metadata
4892  * modifications.
4893  */
4894 static int ext4_freeze(struct super_block *sb)
4895 {
4896         int error = 0;
4897         journal_t *journal;
4898
4899         if (sb->s_flags & MS_RDONLY)
4900                 return 0;
4901
4902         journal = EXT4_SB(sb)->s_journal;
4903
4904         if (journal) {
4905                 /* Now we set up the journal barrier. */
4906                 jbd2_journal_lock_updates(journal);
4907
4908                 /*
4909                  * Don't clear the needs_recovery flag if we failed to
4910                  * flush the journal.
4911                  */
4912                 error = jbd2_journal_flush(journal);
4913                 if (error < 0)
4914                         goto out;
4915
4916                 /* Journal blocked and flushed, clear needs_recovery flag. */
4917                 ext4_clear_feature_journal_needs_recovery(sb);
4918         }
4919
4920         error = ext4_commit_super(sb, 1);
4921 out:
4922         if (journal)
4923                 /* we rely on upper layer to stop further updates */
4924                 jbd2_journal_unlock_updates(journal);
4925         return error;
4926 }
4927
4928 /*
4929  * Called by LVM after the snapshot is done.  We need to reset the RECOVER
4930  * flag here, even though the filesystem is not technically dirty yet.
4931  */
4932 static int ext4_unfreeze(struct super_block *sb)
4933 {
4934         if (sb->s_flags & MS_RDONLY)
4935                 return 0;
4936
4937         if (EXT4_SB(sb)->s_journal) {
4938                 /* Reset the needs_recovery flag before the fs is unlocked. */
4939                 ext4_set_feature_journal_needs_recovery(sb);
4940         }
4941
4942         ext4_commit_super(sb, 1);
4943         return 0;
4944 }
4945
4946 /*
4947  * Structure to save mount options for ext4_remount's benefit
4948  */
4949 struct ext4_mount_options {
4950         unsigned long s_mount_opt;
4951         unsigned long s_mount_opt2;
4952         kuid_t s_resuid;
4953         kgid_t s_resgid;
4954         unsigned long s_commit_interval;
4955         u32 s_min_batch_time, s_max_batch_time;
4956 #ifdef CONFIG_QUOTA
4957         int s_jquota_fmt;
4958         char *s_qf_names[EXT4_MAXQUOTAS];
4959 #endif
4960 };
4961
4962 static int ext4_remount(struct super_block *sb, int *flags, char *data)
4963 {
4964         struct ext4_super_block *es;
4965         struct ext4_sb_info *sbi = EXT4_SB(sb);
4966         unsigned long old_sb_flags;
4967         struct ext4_mount_options old_opts;
4968         int enable_quota = 0;
4969         ext4_group_t g;
4970         unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
4971         int err = 0;
4972 #ifdef CONFIG_QUOTA
4973         int i, j;
4974 #endif
4975         char *orig_data = kstrdup(data, GFP_KERNEL);
4976
4977         /* Store the original options */
4978         old_sb_flags = sb->s_flags;
4979         old_opts.s_mount_opt = sbi->s_mount_opt;
4980         old_opts.s_mount_opt2 = sbi->s_mount_opt2;
4981         old_opts.s_resuid = sbi->s_resuid;
4982         old_opts.s_resgid = sbi->s_resgid;
4983         old_opts.s_commit_interval = sbi->s_commit_interval;
4984         old_opts.s_min_batch_time = sbi->s_min_batch_time;
4985         old_opts.s_max_batch_time = sbi->s_max_batch_time;
4986 #ifdef CONFIG_QUOTA
4987         old_opts.s_jquota_fmt = sbi->s_jquota_fmt;
4988         for (i = 0; i < EXT4_MAXQUOTAS; i++)
4989                 if (sbi->s_qf_names[i]) {
4990                         old_opts.s_qf_names[i] = kstrdup(sbi->s_qf_names[i],
4991                                                          GFP_KERNEL);
4992                         if (!old_opts.s_qf_names[i]) {
4993                                 for (j = 0; j < i; j++)
4994                                         kfree(old_opts.s_qf_names[j]);
4995                                 kfree(orig_data);
4996                                 return -ENOMEM;
4997                         }
4998                 } else
4999                         old_opts.s_qf_names[i] = NULL;
5000 #endif
5001         if (sbi->s_journal && sbi->s_journal->j_task->io_context)
5002                 journal_ioprio = sbi->s_journal->j_task->io_context->ioprio;
5003
5004         if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) {
5005                 err = -EINVAL;
5006                 goto restore_opts;
5007         }
5008
5009         ext4_clamp_want_extra_isize(sb);
5010
5011         if ((old_opts.s_mount_opt & EXT4_MOUNT_JOURNAL_CHECKSUM) ^
5012             test_opt(sb, JOURNAL_CHECKSUM)) {
5013                 ext4_msg(sb, KERN_ERR, "changing journal_checksum "
5014                          "during remount not supported; ignoring");
5015                 sbi->s_mount_opt ^= EXT4_MOUNT_JOURNAL_CHECKSUM;
5016         }
5017
5018         if (test_opt(sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA) {
5019                 if (test_opt2(sb, EXPLICIT_DELALLOC)) {
5020                         ext4_msg(sb, KERN_ERR, "can't mount with "
5021                                  "both data=journal and delalloc");
5022                         err = -EINVAL;
5023                         goto restore_opts;
5024                 }
5025                 if (test_opt(sb, DIOREAD_NOLOCK)) {
5026                         ext4_msg(sb, KERN_ERR, "can't mount with "
5027                                  "both data=journal and dioread_nolock");
5028                         err = -EINVAL;
5029                         goto restore_opts;
5030                 }
5031                 if (test_opt(sb, DAX)) {
5032                         ext4_msg(sb, KERN_ERR, "can't mount with "
5033                                  "both data=journal and dax");
5034                         err = -EINVAL;
5035                         goto restore_opts;
5036                 }
5037         }
5038
5039         if ((sbi->s_mount_opt ^ old_opts.s_mount_opt) & EXT4_MOUNT_DAX) {
5040                 ext4_msg(sb, KERN_WARNING, "warning: refusing change of "
5041                         "dax flag with busy inodes while remounting");
5042                 sbi->s_mount_opt ^= EXT4_MOUNT_DAX;
5043         }
5044
5045         if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED)
5046                 ext4_abort(sb, "Abort forced by user");
5047
5048         sb->s_flags = (sb->s_flags & ~MS_POSIXACL) |
5049                 (test_opt(sb, POSIX_ACL) ? MS_POSIXACL : 0);
5050
5051         es = sbi->s_es;
5052
5053         if (sbi->s_journal) {
5054                 ext4_init_journal_params(sb, sbi->s_journal);
5055                 set_task_ioprio(sbi->s_journal->j_task, journal_ioprio);
5056         }
5057
5058         if (*flags & MS_LAZYTIME)
5059                 sb->s_flags |= MS_LAZYTIME;
5060
5061         if ((*flags & MS_RDONLY) != (sb->s_flags & MS_RDONLY)) {
5062                 if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) {
5063                         err = -EROFS;
5064                         goto restore_opts;
5065                 }
5066
5067                 if (*flags & MS_RDONLY) {
5068                         err = sync_filesystem(sb);
5069                         if (err < 0)
5070                                 goto restore_opts;
5071                         err = dquot_suspend(sb, -1);
5072                         if (err < 0)
5073                                 goto restore_opts;
5074
5075                         /*
5076                          * First of all, the unconditional stuff we have to do
5077                          * to disable replay of the journal when we next remount
5078                          */
5079                         sb->s_flags |= MS_RDONLY;
5080
5081                         /*
5082                          * OK, test if we are remounting a valid rw partition
5083                          * readonly, and if so set the rdonly flag and then
5084                          * mark the partition as valid again.
5085                          */
5086                         if (!(es->s_state & cpu_to_le16(EXT4_VALID_FS)) &&
5087                             (sbi->s_mount_state & EXT4_VALID_FS))
5088                                 es->s_state = cpu_to_le16(sbi->s_mount_state);
5089
5090                         if (sbi->s_journal)
5091                                 ext4_mark_recovery_complete(sb, es);
5092                 } else {
5093                         /* Make sure we can mount this feature set readwrite */
5094                         if (ext4_has_feature_readonly(sb) ||
5095                             !ext4_feature_set_ok(sb, 0)) {
5096                                 err = -EROFS;
5097                                 goto restore_opts;
5098                         }
5099                         /*
5100                          * Make sure the group descriptor checksums
5101                          * are sane.  If they aren't, refuse to remount r/w.
5102                          */
5103                         for (g = 0; g < sbi->s_groups_count; g++) {
5104                                 struct ext4_group_desc *gdp =
5105                                         ext4_get_group_desc(sb, g, NULL);
5106
5107                                 if (!ext4_group_desc_csum_verify(sb, g, gdp)) {
5108                                         ext4_msg(sb, KERN_ERR,
5109                "ext4_remount: Checksum for group %u failed (%u!=%u)",
5110                 g, le16_to_cpu(ext4_group_desc_csum(sb, g, gdp)),
5111                                                le16_to_cpu(gdp->bg_checksum));
5112                                         err = -EFSBADCRC;
5113                                         goto restore_opts;
5114                                 }
5115                         }
5116
5117                         /*
5118                          * If we have an unprocessed orphan list hanging
5119                          * around from a previously readonly bdev mount,
5120                          * require a full umount/remount for now.
5121                          */
5122                         if (es->s_last_orphan) {
5123                                 ext4_msg(sb, KERN_WARNING, "Couldn't "
5124                                        "remount RDWR because of unprocessed "
5125                                        "orphan inode list.  Please "
5126                                        "umount/remount instead");
5127                                 err = -EINVAL;
5128                                 goto restore_opts;
5129                         }
5130
5131                         /*
5132                          * Mounting a RDONLY partition read-write, so reread
5133                          * and store the current valid flag.  (It may have
5134                          * been changed by e2fsck since we originally mounted
5135                          * the partition.)
5136                          */
5137                         if (sbi->s_journal)
5138                                 ext4_clear_journal_err(sb, es);
5139                         sbi->s_mount_state = le16_to_cpu(es->s_state);
5140                         if (!ext4_setup_super(sb, es, 0))
5141                                 sb->s_flags &= ~MS_RDONLY;
5142                         if (ext4_has_feature_mmp(sb))
5143                                 if (ext4_multi_mount_protect(sb,
5144                                                 le64_to_cpu(es->s_mmp_block))) {
5145                                         err = -EROFS;
5146                                         goto restore_opts;
5147                                 }
5148                         enable_quota = 1;
5149                 }
5150         }
5151
5152         /*
5153          * Reinitialize lazy itable initialization thread based on
5154          * current settings
5155          */
5156         if ((sb->s_flags & MS_RDONLY) || !test_opt(sb, INIT_INODE_TABLE))
5157                 ext4_unregister_li_request(sb);
5158         else {
5159                 ext4_group_t first_not_zeroed;
5160                 first_not_zeroed = ext4_has_uninit_itable(sb);
5161                 ext4_register_li_request(sb, first_not_zeroed);
5162         }
5163
5164         err = ext4_setup_system_zone(sb);
5165         if (err)
5166                 goto restore_opts;
5167
5168         if (sbi->s_journal == NULL && !(old_sb_flags & MS_RDONLY))
5169                 ext4_commit_super(sb, 1);
5170
5171 #ifdef CONFIG_QUOTA
5172         /* Release old quota file names */
5173         for (i = 0; i < EXT4_MAXQUOTAS; i++)
5174                 kfree(old_opts.s_qf_names[i]);
5175         if (enable_quota) {
5176                 if (sb_any_quota_suspended(sb))
5177                         dquot_resume(sb, -1);
5178                 else if (ext4_has_feature_quota(sb)) {
5179                         err = ext4_enable_quotas(sb);
5180                         if (err)
5181                                 goto restore_opts;
5182                 }
5183         }
5184 #endif
5185
5186         *flags = (*flags & ~MS_LAZYTIME) | (sb->s_flags & MS_LAZYTIME);
5187         ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data);
5188         kfree(orig_data);
5189         return 0;
5190
5191 restore_opts:
5192         sb->s_flags = old_sb_flags;
5193         sbi->s_mount_opt = old_opts.s_mount_opt;
5194         sbi->s_mount_opt2 = old_opts.s_mount_opt2;
5195         sbi->s_resuid = old_opts.s_resuid;
5196         sbi->s_resgid = old_opts.s_resgid;
5197         sbi->s_commit_interval = old_opts.s_commit_interval;
5198         sbi->s_min_batch_time = old_opts.s_min_batch_time;
5199         sbi->s_max_batch_time = old_opts.s_max_batch_time;
5200 #ifdef CONFIG_QUOTA
5201         sbi->s_jquota_fmt = old_opts.s_jquota_fmt;
5202         for (i = 0; i < EXT4_MAXQUOTAS; i++) {
5203                 kfree(sbi->s_qf_names[i]);
5204                 sbi->s_qf_names[i] = old_opts.s_qf_names[i];
5205         }
5206 #endif
5207         kfree(orig_data);
5208         return err;
5209 }
5210
5211 #ifdef CONFIG_QUOTA
5212 static int ext4_statfs_project(struct super_block *sb,
5213                                kprojid_t projid, struct kstatfs *buf)
5214 {
5215         struct kqid qid;
5216         struct dquot *dquot;
5217         u64 limit;
5218         u64 curblock;
5219
5220         qid = make_kqid_projid(projid);
5221         dquot = dqget(sb, qid);
5222         if (IS_ERR(dquot))
5223                 return PTR_ERR(dquot);
5224         spin_lock(&dq_data_lock);
5225
5226         limit = (dquot->dq_dqb.dqb_bsoftlimit ?
5227                  dquot->dq_dqb.dqb_bsoftlimit :
5228                  dquot->dq_dqb.dqb_bhardlimit) >> sb->s_blocksize_bits;
5229         if (limit && buf->f_blocks > limit) {
5230                 curblock = dquot->dq_dqb.dqb_curspace >> sb->s_blocksize_bits;
5231                 buf->f_blocks = limit;
5232                 buf->f_bfree = buf->f_bavail =
5233                         (buf->f_blocks > curblock) ?
5234                          (buf->f_blocks - curblock) : 0;
5235         }
5236
5237         limit = dquot->dq_dqb.dqb_isoftlimit ?
5238                 dquot->dq_dqb.dqb_isoftlimit :
5239                 dquot->dq_dqb.dqb_ihardlimit;
5240         if (limit && buf->f_files > limit) {
5241                 buf->f_files = limit;
5242                 buf->f_ffree =
5243                         (buf->f_files > dquot->dq_dqb.dqb_curinodes) ?
5244                          (buf->f_files - dquot->dq_dqb.dqb_curinodes) : 0;
5245         }
5246
5247         spin_unlock(&dq_data_lock);
5248         dqput(dquot);
5249         return 0;
5250 }
5251 #endif
5252
5253 static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
5254 {
5255         struct super_block *sb = dentry->d_sb;
5256         struct ext4_sb_info *sbi = EXT4_SB(sb);
5257         struct ext4_super_block *es = sbi->s_es;
5258         ext4_fsblk_t overhead = 0, resv_blocks;
5259         u64 fsid;
5260         s64 bfree;
5261         resv_blocks = EXT4_C2B(sbi, atomic64_read(&sbi->s_resv_clusters));
5262
5263         if (!test_opt(sb, MINIX_DF))
5264                 overhead = sbi->s_overhead;
5265
5266         buf->f_type = EXT4_SUPER_MAGIC;
5267         buf->f_bsize = sb->s_blocksize;
5268         buf->f_blocks = ext4_blocks_count(es) - EXT4_C2B(sbi, overhead);
5269         bfree = percpu_counter_sum_positive(&sbi->s_freeclusters_counter) -
5270                 percpu_counter_sum_positive(&sbi->s_dirtyclusters_counter);
5271         /* prevent underflow in case that few free space is available */
5272         buf->f_bfree = EXT4_C2B(sbi, max_t(s64, bfree, 0));
5273         buf->f_bavail = buf->f_bfree -
5274                         (ext4_r_blocks_count(es) + resv_blocks);
5275         if (buf->f_bfree < (ext4_r_blocks_count(es) + resv_blocks))
5276                 buf->f_bavail = 0;
5277         buf->f_files = le32_to_cpu(es->s_inodes_count);
5278         buf->f_ffree = percpu_counter_sum_positive(&sbi->s_freeinodes_counter);
5279         buf->f_namelen = EXT4_NAME_LEN;
5280         fsid = le64_to_cpup((void *)es->s_uuid) ^
5281                le64_to_cpup((void *)es->s_uuid + sizeof(u64));
5282         buf->f_fsid.val[0] = fsid & 0xFFFFFFFFUL;
5283         buf->f_fsid.val[1] = (fsid >> 32) & 0xFFFFFFFFUL;
5284
5285 #ifdef CONFIG_QUOTA
5286         if (ext4_test_inode_flag(dentry->d_inode, EXT4_INODE_PROJINHERIT) &&
5287             sb_has_quota_limits_enabled(sb, PRJQUOTA))
5288                 ext4_statfs_project(sb, EXT4_I(dentry->d_inode)->i_projid, buf);
5289 #endif
5290         return 0;
5291 }
5292
5293 /* Helper function for writing quotas on sync - we need to start transaction
5294  * before quota file is locked for write. Otherwise the are possible deadlocks:
5295  * Process 1                         Process 2
5296  * ext4_create()                     quota_sync()
5297  *   jbd2_journal_start()                  write_dquot()
5298  *   dquot_initialize()                         down(dqio_mutex)
5299  *     down(dqio_mutex)                    jbd2_journal_start()
5300  *
5301  */
5302
5303 #ifdef CONFIG_QUOTA
5304
5305 static inline struct inode *dquot_to_inode(struct dquot *dquot)
5306 {
5307         return sb_dqopt(dquot->dq_sb)->files[dquot->dq_id.type];
5308 }
5309
5310 static int ext4_write_dquot(struct dquot *dquot)
5311 {
5312         int ret, err;
5313         handle_t *handle;
5314         struct inode *inode;
5315
5316         inode = dquot_to_inode(dquot);
5317         handle = ext4_journal_start(inode, EXT4_HT_QUOTA,
5318                                     EXT4_QUOTA_TRANS_BLOCKS(dquot->dq_sb));
5319         if (IS_ERR(handle))
5320                 return PTR_ERR(handle);
5321         ret = dquot_commit(dquot);
5322         err = ext4_journal_stop(handle);
5323         if (!ret)
5324                 ret = err;
5325         return ret;
5326 }
5327
5328 static int ext4_acquire_dquot(struct dquot *dquot)
5329 {
5330         int ret, err;
5331         handle_t *handle;
5332
5333         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5334                                     EXT4_QUOTA_INIT_BLOCKS(dquot->dq_sb));
5335         if (IS_ERR(handle))
5336                 return PTR_ERR(handle);
5337         ret = dquot_acquire(dquot);
5338         err = ext4_journal_stop(handle);
5339         if (!ret)
5340                 ret = err;
5341         return ret;
5342 }
5343
5344 static int ext4_release_dquot(struct dquot *dquot)
5345 {
5346         int ret, err;
5347         handle_t *handle;
5348
5349         handle = ext4_journal_start(dquot_to_inode(dquot), EXT4_HT_QUOTA,
5350                                     EXT4_QUOTA_DEL_BLOCKS(dquot->dq_sb));
5351         if (IS_ERR(handle)) {
5352                 /* Release dquot anyway to avoid endless cycle in dqput() */
5353                 dquot_release(dquot);
5354                 return PTR_ERR(handle);
5355         }
5356         ret = dquot_release(dquot);
5357         err = ext4_journal_stop(handle);
5358         if (!ret)
5359                 ret = err;
5360         return ret;
5361 }
5362
5363 static int ext4_mark_dquot_dirty(struct dquot *dquot)
5364 {
5365         struct super_block *sb = dquot->dq_sb;
5366         struct ext4_sb_info *sbi = EXT4_SB(sb);
5367
5368         /* Are we journaling quotas? */
5369         if (ext4_has_feature_quota(sb) ||
5370             sbi->s_qf_names[USRQUOTA] || sbi->s_qf_names[GRPQUOTA]) {
5371                 dquot_mark_dquot_dirty(dquot);
5372                 return ext4_write_dquot(dquot);
5373         } else {
5374                 return dquot_mark_dquot_dirty(dquot);
5375         }
5376 }
5377
5378 static int ext4_write_info(struct super_block *sb, int type)
5379 {
5380         int ret, err;
5381         handle_t *handle;
5382
5383         /* Data block + inode block */
5384         handle = ext4_journal_start(d_inode(sb->s_root), EXT4_HT_QUOTA, 2);
5385         if (IS_ERR(handle))
5386                 return PTR_ERR(handle);
5387         ret = dquot_commit_info(sb, type);
5388         err = ext4_journal_stop(handle);
5389         if (!ret)
5390                 ret = err;
5391         return ret;
5392 }
5393
5394 /*
5395  * Turn on quotas during mount time - we need to find
5396  * the quota file and such...
5397  */
5398 static int ext4_quota_on_mount(struct super_block *sb, int type)
5399 {
5400         return dquot_quota_on_mount(sb, EXT4_SB(sb)->s_qf_names[type],
5401                                         EXT4_SB(sb)->s_jquota_fmt, type);
5402 }
5403
5404 static void lockdep_set_quota_inode(struct inode *inode, int subclass)
5405 {
5406         struct ext4_inode_info *ei = EXT4_I(inode);
5407
5408         /* The first argument of lockdep_set_subclass has to be
5409          * *exactly* the same as the argument to init_rwsem() --- in
5410          * this case, in init_once() --- or lockdep gets unhappy
5411          * because the name of the lock is set using the
5412          * stringification of the argument to init_rwsem().
5413          */
5414         (void) ei;      /* shut up clang warning if !CONFIG_LOCKDEP */
5415         lockdep_set_subclass(&ei->i_data_sem, subclass);
5416 }
5417
5418 /*
5419  * Standard function to be called on quota_on
5420  */
5421 static int ext4_quota_on(struct super_block *sb, int type, int format_id,
5422                          struct path *path)
5423 {
5424         int err;
5425
5426         if (!test_opt(sb, QUOTA))
5427                 return -EINVAL;
5428
5429         /* Quotafile not on the same filesystem? */
5430         if (path->dentry->d_sb != sb)
5431                 return -EXDEV;
5432
5433         /* Quota already enabled for this file? */
5434         if (IS_NOQUOTA(d_inode(path->dentry)))
5435                 return -EBUSY;
5436
5437         /* Journaling quota? */
5438         if (EXT4_SB(sb)->s_qf_names[type]) {
5439                 /* Quotafile not in fs root? */
5440                 if (path->dentry->d_parent != sb->s_root)
5441                         ext4_msg(sb, KERN_WARNING,
5442                                 "Quota file not on filesystem root. "
5443                                 "Journaled quota will not work");
5444         }
5445
5446         /*
5447          * When we journal data on quota file, we have to flush journal to see
5448          * all updates to the file when we bypass pagecache...
5449          */
5450         if (EXT4_SB(sb)->s_journal &&
5451             ext4_should_journal_data(d_inode(path->dentry))) {
5452                 /*
5453                  * We don't need to lock updates but journal_flush() could
5454                  * otherwise be livelocked...
5455                  */
5456                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
5457                 err = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
5458                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
5459                 if (err)
5460                         return err;
5461         }
5462         lockdep_set_quota_inode(path->dentry->d_inode, I_DATA_SEM_QUOTA);
5463         err = dquot_quota_on(sb, type, format_id, path);
5464         if (err)
5465                 lockdep_set_quota_inode(path->dentry->d_inode,
5466                                              I_DATA_SEM_NORMAL);
5467         return err;
5468 }
5469
5470 static int ext4_quota_enable(struct super_block *sb, int type, int format_id,
5471                              unsigned int flags)
5472 {
5473         int err;
5474         struct inode *qf_inode;
5475         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
5476                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
5477                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
5478                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
5479         };
5480
5481         BUG_ON(!ext4_has_feature_quota(sb));
5482
5483         if (!qf_inums[type])
5484                 return -EPERM;
5485
5486         qf_inode = ext4_iget(sb, qf_inums[type], EXT4_IGET_SPECIAL);
5487         if (IS_ERR(qf_inode)) {
5488                 ext4_error(sb, "Bad quota inode # %lu", qf_inums[type]);
5489                 return PTR_ERR(qf_inode);
5490         }
5491
5492         /* Don't account quota for quota files to avoid recursion */
5493         qf_inode->i_flags |= S_NOQUOTA;
5494         lockdep_set_quota_inode(qf_inode, I_DATA_SEM_QUOTA);
5495         err = dquot_enable(qf_inode, type, format_id, flags);
5496         if (err)
5497                 lockdep_set_quota_inode(qf_inode, I_DATA_SEM_NORMAL);
5498         iput(qf_inode);
5499
5500         return err;
5501 }
5502
5503 /* Enable usage tracking for all quota types. */
5504 static int ext4_enable_quotas(struct super_block *sb)
5505 {
5506         int type, err = 0;
5507         unsigned long qf_inums[EXT4_MAXQUOTAS] = {
5508                 le32_to_cpu(EXT4_SB(sb)->s_es->s_usr_quota_inum),
5509                 le32_to_cpu(EXT4_SB(sb)->s_es->s_grp_quota_inum),
5510                 le32_to_cpu(EXT4_SB(sb)->s_es->s_prj_quota_inum)
5511         };
5512         bool quota_mopt[EXT4_MAXQUOTAS] = {
5513                 test_opt(sb, USRQUOTA),
5514                 test_opt(sb, GRPQUOTA),
5515                 test_opt(sb, PRJQUOTA),
5516         };
5517
5518         sb_dqopt(sb)->flags |= DQUOT_QUOTA_SYS_FILE;
5519         for (type = 0; type < EXT4_MAXQUOTAS; type++) {
5520                 if (qf_inums[type]) {
5521                         err = ext4_quota_enable(sb, type, QFMT_VFS_V1,
5522                                 DQUOT_USAGE_ENABLED |
5523                                 (quota_mopt[type] ? DQUOT_LIMITS_ENABLED : 0));
5524                         if (err) {
5525                                 for (type--; type >= 0; type--)
5526                                         dquot_quota_off(sb, type);
5527
5528                                 ext4_warning(sb,
5529                                         "Failed to enable quota tracking "
5530                                         "(type=%d, err=%d). Please run "
5531                                         "e2fsck to fix.", type, err);
5532                                 return err;
5533                         }
5534                 }
5535         }
5536         return 0;
5537 }
5538
5539 static int ext4_quota_off(struct super_block *sb, int type)
5540 {
5541         struct inode *inode = sb_dqopt(sb)->files[type];
5542         handle_t *handle;
5543
5544         /* Force all delayed allocation blocks to be allocated.
5545          * Caller already holds s_umount sem */
5546         if (test_opt(sb, DELALLOC))
5547                 sync_filesystem(sb);
5548
5549         if (!inode)
5550                 goto out;
5551
5552         /* Update modification times of quota files when userspace can
5553          * start looking at them */
5554         handle = ext4_journal_start(inode, EXT4_HT_QUOTA, 1);
5555         if (IS_ERR(handle))
5556                 goto out;
5557         inode->i_mtime = inode->i_ctime = CURRENT_TIME;
5558         ext4_mark_inode_dirty(handle, inode);
5559         ext4_journal_stop(handle);
5560
5561 out:
5562         return dquot_quota_off(sb, type);
5563 }
5564
5565 /* Read data from quotafile - avoid pagecache and such because we cannot afford
5566  * acquiring the locks... As quota files are never truncated and quota code
5567  * itself serializes the operations (and no one else should touch the files)
5568  * we don't have to be afraid of races */
5569 static ssize_t ext4_quota_read(struct super_block *sb, int type, char *data,
5570                                size_t len, loff_t off)
5571 {
5572         struct inode *inode = sb_dqopt(sb)->files[type];
5573         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
5574         int offset = off & (sb->s_blocksize - 1);
5575         int tocopy;
5576         size_t toread;
5577         struct buffer_head *bh;
5578         loff_t i_size = i_size_read(inode);
5579
5580         if (off > i_size)
5581                 return 0;
5582         if (off+len > i_size)
5583                 len = i_size-off;
5584         toread = len;
5585         while (toread > 0) {
5586                 tocopy = sb->s_blocksize - offset < toread ?
5587                                 sb->s_blocksize - offset : toread;
5588                 bh = ext4_bread(NULL, inode, blk, 0);
5589                 if (IS_ERR(bh))
5590                         return PTR_ERR(bh);
5591                 if (!bh)        /* A hole? */
5592                         memset(data, 0, tocopy);
5593                 else
5594                         memcpy(data, bh->b_data+offset, tocopy);
5595                 brelse(bh);
5596                 offset = 0;
5597                 toread -= tocopy;
5598                 data += tocopy;
5599                 blk++;
5600         }
5601         return len;
5602 }
5603
5604 /* Write to quotafile (we know the transaction is already started and has
5605  * enough credits) */
5606 static ssize_t ext4_quota_write(struct super_block *sb, int type,
5607                                 const char *data, size_t len, loff_t off)
5608 {
5609         struct inode *inode = sb_dqopt(sb)->files[type];
5610         ext4_lblk_t blk = off >> EXT4_BLOCK_SIZE_BITS(sb);
5611         int err, offset = off & (sb->s_blocksize - 1);
5612         int retries = 0;
5613         struct buffer_head *bh;
5614         handle_t *handle = journal_current_handle();
5615
5616         if (!handle) {
5617                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
5618                         " cancelled because transaction is not started",
5619                         (unsigned long long)off, (unsigned long long)len);
5620                 return -EIO;
5621         }
5622         /*
5623          * Since we account only one data block in transaction credits,
5624          * then it is impossible to cross a block boundary.
5625          */
5626         if (sb->s_blocksize - offset < len) {
5627                 ext4_msg(sb, KERN_WARNING, "Quota write (off=%llu, len=%llu)"
5628                         " cancelled because not block aligned",
5629                         (unsigned long long)off, (unsigned long long)len);
5630                 return -EIO;
5631         }
5632
5633         do {
5634                 bh = ext4_bread(handle, inode, blk,
5635                                 EXT4_GET_BLOCKS_CREATE |
5636                                 EXT4_GET_BLOCKS_METADATA_NOFAIL);
5637         } while (IS_ERR(bh) && (PTR_ERR(bh) == -ENOSPC) &&
5638                  ext4_should_retry_alloc(inode->i_sb, &retries));
5639         if (IS_ERR(bh))
5640                 return PTR_ERR(bh);
5641         if (!bh)
5642                 goto out;
5643         BUFFER_TRACE(bh, "get write access");
5644         err = ext4_journal_get_write_access(handle, bh);
5645         if (err) {
5646                 brelse(bh);
5647                 return err;
5648         }
5649         lock_buffer(bh);
5650         memcpy(bh->b_data+offset, data, len);
5651         flush_dcache_page(bh->b_page);
5652         unlock_buffer(bh);
5653         err = ext4_handle_dirty_metadata(handle, NULL, bh);
5654         brelse(bh);
5655 out:
5656         if (inode->i_size < off + len) {
5657                 i_size_write(inode, off + len);
5658                 EXT4_I(inode)->i_disksize = inode->i_size;
5659                 ext4_mark_inode_dirty(handle, inode);
5660         }
5661         return len;
5662 }
5663
5664 static int ext4_get_next_id(struct super_block *sb, struct kqid *qid)
5665 {
5666         const struct quota_format_ops   *ops;
5667
5668         if (!sb_has_quota_loaded(sb, qid->type))
5669                 return -ESRCH;
5670         ops = sb_dqopt(sb)->ops[qid->type];
5671         if (!ops || !ops->get_next_id)
5672                 return -ENOSYS;
5673         return dquot_get_next_id(sb, qid);
5674 }
5675 #endif
5676
5677 static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags,
5678                        const char *dev_name, void *data)
5679 {
5680         return mount_bdev(fs_type, flags, dev_name, data, ext4_fill_super);
5681 }
5682
5683 #if !defined(CONFIG_EXT2_FS) && !defined(CONFIG_EXT2_FS_MODULE) && defined(CONFIG_EXT4_USE_FOR_EXT2)
5684 static inline void register_as_ext2(void)
5685 {
5686         int err = register_filesystem(&ext2_fs_type);
5687         if (err)
5688                 printk(KERN_WARNING
5689                        "EXT4-fs: Unable to register as ext2 (%d)\n", err);
5690 }
5691
5692 static inline void unregister_as_ext2(void)
5693 {
5694         unregister_filesystem(&ext2_fs_type);
5695 }
5696
5697 static inline int ext2_feature_set_ok(struct super_block *sb)
5698 {
5699         if (ext4_has_unknown_ext2_incompat_features(sb))
5700                 return 0;
5701         if (sb->s_flags & MS_RDONLY)
5702                 return 1;
5703         if (ext4_has_unknown_ext2_ro_compat_features(sb))
5704                 return 0;
5705         return 1;
5706 }
5707 #else
5708 static inline void register_as_ext2(void) { }
5709 static inline void unregister_as_ext2(void) { }
5710 static inline int ext2_feature_set_ok(struct super_block *sb) { return 0; }
5711 #endif
5712
5713 static inline void register_as_ext3(void)
5714 {
5715         int err = register_filesystem(&ext3_fs_type);
5716         if (err)
5717                 printk(KERN_WARNING
5718                        "EXT4-fs: Unable to register as ext3 (%d)\n", err);
5719 }
5720
5721 static inline void unregister_as_ext3(void)
5722 {
5723         unregister_filesystem(&ext3_fs_type);
5724 }
5725
5726 static inline int ext3_feature_set_ok(struct super_block *sb)
5727 {
5728         if (ext4_has_unknown_ext3_incompat_features(sb))
5729                 return 0;
5730         if (!ext4_has_feature_journal(sb))
5731                 return 0;
5732         if (sb->s_flags & MS_RDONLY)
5733                 return 1;
5734         if (ext4_has_unknown_ext3_ro_compat_features(sb))
5735                 return 0;
5736         return 1;
5737 }
5738
5739 static struct file_system_type ext4_fs_type = {
5740         .owner          = THIS_MODULE,
5741         .name           = "ext4",
5742         .mount          = ext4_mount,
5743         .kill_sb        = kill_block_super,
5744         .fs_flags       = FS_REQUIRES_DEV,
5745 };
5746 MODULE_ALIAS_FS("ext4");
5747
5748 /* Shared across all ext4 file systems */
5749 wait_queue_head_t ext4__ioend_wq[EXT4_WQ_HASH_SZ];
5750
5751 static int __init ext4_init_fs(void)
5752 {
5753         int i, err;
5754
5755         ratelimit_state_init(&ext4_mount_msg_ratelimit, 30 * HZ, 64);
5756         ext4_li_info = NULL;
5757         mutex_init(&ext4_li_mtx);
5758
5759         /* Build-time check for flags consistency */
5760         ext4_check_flag_values();
5761
5762         for (i = 0; i < EXT4_WQ_HASH_SZ; i++)
5763                 init_waitqueue_head(&ext4__ioend_wq[i]);
5764
5765         err = ext4_init_es();
5766         if (err)
5767                 return err;
5768
5769         err = ext4_init_pageio();
5770         if (err)
5771                 goto out5;
5772
5773         err = ext4_init_system_zone();
5774         if (err)
5775                 goto out4;
5776
5777         err = ext4_init_sysfs();
5778         if (err)
5779                 goto out3;
5780
5781         err = ext4_init_mballoc();
5782         if (err)
5783                 goto out2;
5784         err = init_inodecache();
5785         if (err)
5786                 goto out1;
5787         register_as_ext3();
5788         register_as_ext2();
5789         err = register_filesystem(&ext4_fs_type);
5790         if (err)
5791                 goto out;
5792
5793         return 0;
5794 out:
5795         unregister_as_ext2();
5796         unregister_as_ext3();
5797         destroy_inodecache();
5798 out1:
5799         ext4_exit_mballoc();
5800 out2:
5801         ext4_exit_sysfs();
5802 out3:
5803         ext4_exit_system_zone();
5804 out4:
5805         ext4_exit_pageio();
5806 out5:
5807         ext4_exit_es();
5808
5809         return err;
5810 }
5811
5812 static void __exit ext4_exit_fs(void)
5813 {
5814         ext4_destroy_lazyinit_thread();
5815         unregister_as_ext2();
5816         unregister_as_ext3();
5817         unregister_filesystem(&ext4_fs_type);
5818         destroy_inodecache();
5819         ext4_exit_mballoc();
5820         ext4_exit_sysfs();
5821         ext4_exit_system_zone();
5822         ext4_exit_pageio();
5823         ext4_exit_es();
5824 }
5825
5826 MODULE_AUTHOR("Remy Card, Stephen Tweedie, Andrew Morton, Andreas Dilger, Theodore Ts'o and others");
5827 MODULE_DESCRIPTION("Fourth Extended Filesystem");
5828 MODULE_LICENSE("GPL");
5829 module_init(ext4_init_fs)
5830 module_exit(ext4_exit_fs)