inode.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  linux/fs/affs/inode.c
   4  *
   5  *  (c) 1996  Hans-Joachim Widmaier - Rewritten
   6  *
   7  *  (C) 1993  Ray Burr - Modified for Amiga FFS filesystem.
   8  *
   9  *  (C) 1992  Eric Youngdale Modified for ISO9660 filesystem.
  10  *
  11  *  (C) 1991  Linus Torvalds - minix filesystem
  12  */
  13 #include <linux/sched.h>
  14 #include <linux/cred.h>
  15 #include <linux/gfp.h>
  16 #include "affs.h"
  17
  18 struct inode *affs_iget(struct super_block *sb, unsigned long ino)
  19 {
  20         struct affs_sb_info     *sbi = AFFS_SB(sb);
  21         struct buffer_head      *bh;
  22         struct affs_tail        *tail;
  23         struct inode            *inode;
  24         u32                      block;
  25         u32                      size;
  26         u32                      prot;
  27         u16                      id;
  28
  29         inode = iget_locked(sb, ino);
  30         if (!inode)
  31                 return ERR_PTR(-ENOMEM);
  32         if (!(inode->i_state & I_NEW))
  33                 return inode;
  34
  35         pr_debug("affs_iget(%lu)\n", inode->i_ino);
  36
  37         block = inode->i_ino;
  38         bh = affs_bread(sb, block);
  39         if (!bh) {
  40                 affs_warning(sb, "read_inode", "Cannot read block %d", block);
  41                 goto bad_inode;
  42         }
  43         if (affs_checksum_block(sb, bh) || be32_to_cpu(AFFS_HEAD(bh)->ptype) != T_SHORT) {
  44                 affs_warning(sb,"read_inode",
  45                            "Checksum or type (ptype=%d) error on inode %d",
  46                            AFFS_HEAD(bh)->ptype, block);
  47                 goto bad_inode;
  48         }
  49
  50         tail = AFFS_TAIL(sb, bh);
  51         prot = be32_to_cpu(tail->protect);
  52
  53         inode->i_size = 0;
  54         set_nlink(inode, 1);
  55         inode->i_mode = 0;
  56         AFFS_I(inode)->i_extcnt = 1;
  57         AFFS_I(inode)->i_ext_last = ~1;
  58         AFFS_I(inode)->i_protect = prot;
  59         atomic_set(&AFFS_I(inode)->i_opencnt, 0);
  60         AFFS_I(inode)->i_blkcnt = 0;
  61         AFFS_I(inode)->i_lc = NULL;
  62         AFFS_I(inode)->i_lc_size = 0;
  63         AFFS_I(inode)->i_lc_shift = 0;
  64         AFFS_I(inode)->i_lc_mask = 0;
  65         AFFS_I(inode)->i_ac = NULL;
  66         AFFS_I(inode)->i_ext_bh = NULL;
  67         AFFS_I(inode)->mmu_private = 0;
  68         AFFS_I(inode)->i_lastalloc = 0;
  69         AFFS_I(inode)->i_pa_cnt = 0;
  70
  71         if (affs_test_opt(sbi->s_flags, SF_SETMODE))
  72                 inode->i_mode = sbi->s_mode;
  73         else
  74                 inode->i_mode = affs_prot_to_mode(prot);
  75
  76         id = be16_to_cpu(tail->uid);
  77         if (id == 0 || affs_test_opt(sbi->s_flags, SF_SETUID))
  78                 inode->i_uid = sbi->s_uid;
  79         else if (id == 0xFFFF && affs_test_opt(sbi->s_flags, SF_MUFS))
  80                 i_uid_write(inode, 0);
  81         else
  82                 i_uid_write(inode, id);
  83
  84         id = be16_to_cpu(tail->gid);
  85         if (id == 0 || affs_test_opt(sbi->s_flags, SF_SETGID))
  86                 inode->i_gid = sbi->s_gid;
  87         else if (id == 0xFFFF && affs_test_opt(sbi->s_flags, SF_MUFS))
  88                 i_gid_write(inode, 0);
  89         else
  90                 i_gid_write(inode, id);
  91
  92         switch (be32_to_cpu(tail->stype)) {
  93         case ST_ROOT:
  94                 inode->i_uid = sbi->s_uid;
  95                 inode->i_gid = sbi->s_gid;
  96                 fallthrough;
  97         case ST_USERDIR:
  98                 if (be32_to_cpu(tail->stype) == ST_USERDIR ||
  99                     affs_test_opt(sbi->s_flags, SF_SETMODE)) {
 100                         if (inode->i_mode & S_IRUSR)
 101                                 inode->i_mode |= S_IXUSR;
 102                         if (inode->i_mode & S_IRGRP)
 103                                 inode->i_mode |= S_IXGRP;
 104                         if (inode->i_mode & S_IROTH)
 105                                 inode->i_mode |= S_IXOTH;
 106                         inode->i_mode |= S_IFDIR;
 107                 } else
 108                         inode->i_mode = S_IRUGO | S_IXUGO | S_IWUSR | S_IFDIR;
 109                 /* Maybe it should be controlled by mount parameter? */
 110                 //inode->i_mode |= S_ISVTX;
 111                 inode->i_op = &affs_dir_inode_operations;
 112                 inode->i_fop = &affs_dir_operations;
 113                 break;
 114         case ST_LINKDIR:
 115 #if 0
 116                 affs_warning(sb, "read_inode", "inode is LINKDIR");
 117                 goto bad_inode;
 118 #else
 119                 inode->i_mode |= S_IFDIR;
 120                 /* ... and leave ->i_op and ->i_fop pointing to empty */
 121                 break;
 122 #endif
 123         case ST_LINKFILE:
 124                 affs_warning(sb, "read_inode", "inode is LINKFILE");
 125                 goto bad_inode;
 126         case ST_FILE:
 127                 size = be32_to_cpu(tail->size);
 128                 inode->i_mode |= S_IFREG;
 129                 AFFS_I(inode)->mmu_private = inode->i_size = size;
 130                 if (inode->i_size) {
 131                         AFFS_I(inode)->i_blkcnt = (size - 1) /
 132                                                sbi->s_data_blksize + 1;
 133                         AFFS_I(inode)->i_extcnt = (AFFS_I(inode)->i_blkcnt - 1) /
 134                                                sbi->s_hashsize + 1;
 135                 }
 136                 if (tail->link_chain)
 137                         set_nlink(inode, 2);
 138                 inode->i_mapping->a_ops = affs_test_opt(sbi->s_flags, SF_OFS) ?
 139                                           &affs_aops_ofs : &affs_aops;
 140                 inode->i_op = &affs_file_inode_operations;
 141                 inode->i_fop = &affs_file_operations;
 142                 break;
 143         case ST_SOFTLINK:
 144                 inode->i_size = strlen((char *)AFFS_HEAD(bh)->table);
 145                 inode->i_mode |= S_IFLNK;
 146                 inode_nohighmem(inode);
 147                 inode->i_op = &affs_symlink_inode_operations;
 148                 inode->i_data.a_ops = &affs_symlink_aops;
 149                 break;
 150         }
 151
 152         inode_set_mtime(inode,
 153                         inode_set_atime(inode, inode_set_ctime(inode, (be32_to_cpu(tail->change.days) * 86400LL + be32_to_cpu(tail->change.mins) * 60 + be32_to_cpu(tail->change.ticks) / 50 + AFFS_EPOCH_DELTA) + sys_tz.tz_minuteswest * 60, 0).tv_sec, 0).tv_sec,
 154                         0);
 155         affs_brelse(bh);
 156         unlock_new_inode(inode);
 157         return inode;
 158
 159 bad_inode:
 160         affs_brelse(bh);
 161         iget_failed(inode);
 162         return ERR_PTR(-EIO);
 163 }
 164
 165 int
 166 affs_write_inode(struct inode *inode, struct writeback_control *wbc)
 167 {
 168         struct super_block      *sb = inode->i_sb;
 169         struct buffer_head      *bh;
 170         struct affs_tail        *tail;
 171         uid_t                    uid;
 172         gid_t                    gid;
 173
 174         pr_debug("write_inode(%lu)\n", inode->i_ino);
 175
 176         if (!inode->i_nlink)
 177                 // possibly free block
 178                 return 0;
 179         bh = affs_bread(sb, inode->i_ino);
 180         if (!bh) {
 181                 affs_error(sb,"write_inode","Cannot read block %lu",inode->i_ino);
 182                 return -EIO;
 183         }
 184         tail = AFFS_TAIL(sb, bh);
 185         if (tail->stype == cpu_to_be32(ST_ROOT)) {
 186                 affs_secs_to_datestamp(inode_get_mtime_sec(inode),
 187                                        &AFFS_ROOT_TAIL(sb, bh)->root_change);
 188         } else {
 189                 tail->protect = cpu_to_be32(AFFS_I(inode)->i_protect);
 190                 tail->size = cpu_to_be32(inode->i_size);
 191                 affs_secs_to_datestamp(inode_get_mtime_sec(inode),
 192                                        &tail->change);
 193                 if (!(inode->i_ino == AFFS_SB(sb)->s_root_block)) {
 194                         uid = i_uid_read(inode);
 195                         gid = i_gid_read(inode);
 196                         if (affs_test_opt(AFFS_SB(sb)->s_flags, SF_MUFS)) {
 197                                 if (uid == 0 || uid == 0xFFFF)
 198                                         uid = uid ^ ~0;
 199                                 if (gid == 0 || gid == 0xFFFF)
 200                                         gid = gid ^ ~0;
 201                         }
 202                         if (!affs_test_opt(AFFS_SB(sb)->s_flags, SF_SETUID))
 203                                 tail->uid = cpu_to_be16(uid);
 204                         if (!affs_test_opt(AFFS_SB(sb)->s_flags, SF_SETGID))
 205                                 tail->gid = cpu_to_be16(gid);
 206                 }
 207         }
 208         affs_fix_checksum(sb, bh);
 209         mark_buffer_dirty_inode(bh, inode);
 210         affs_brelse(bh);
 211         affs_free_prealloc(inode);
 212         return 0;
 213 }
 214
 215 int
 216 affs_notify_change(struct mnt_idmap *idmap, struct dentry *dentry,
 217                    struct iattr *attr)
 218 {
 219         struct inode *inode = d_inode(dentry);
 220         int error;
 221
 222         pr_debug("notify_change(%lu,0x%x)\n", inode->i_ino, attr->ia_valid);
 223
 224         error = setattr_prepare(&nop_mnt_idmap, dentry, attr);
 225         if (error)
 226                 goto out;
 227
 228         if (((attr->ia_valid & ATTR_UID) &&
 229               affs_test_opt(AFFS_SB(inode->i_sb)->s_flags, SF_SETUID)) ||
 230             ((attr->ia_valid & ATTR_GID) &&
 231               affs_test_opt(AFFS_SB(inode->i_sb)->s_flags, SF_SETGID)) ||
 232             ((attr->ia_valid & ATTR_MODE) &&
 233              (AFFS_SB(inode->i_sb)->s_flags &
 234               (AFFS_MOUNT_SF_SETMODE | AFFS_MOUNT_SF_IMMUTABLE)))) {
 235                 if (!affs_test_opt(AFFS_SB(inode->i_sb)->s_flags, SF_QUIET))
 236                         error = -EPERM;
 237                 goto out;
 238         }
 239
 240         if ((attr->ia_valid & ATTR_SIZE) &&
 241             attr->ia_size != i_size_read(inode)) {
 242                 error = inode_newsize_ok(inode, attr->ia_size);
 243                 if (error)
 244                         return error;
 245
 246                 truncate_setsize(inode, attr->ia_size);
 247                 affs_truncate(inode);
 248         }
 249
 250         setattr_copy(&nop_mnt_idmap, inode, attr);
 251         mark_inode_dirty(inode);
 252
 253         if (attr->ia_valid & ATTR_MODE)
 254                 affs_mode_to_prot(inode);
 255 out:
 256         return error;
 257 }
 258
 259 void
 260 affs_evict_inode(struct inode *inode)
 261 {
 262         unsigned long cache_page;
 263         pr_debug("evict_inode(ino=%lu, nlink=%u)\n",
 264                  inode->i_ino, inode->i_nlink);
 265         truncate_inode_pages_final(&inode->i_data);
 266
 267         if (!inode->i_nlink) {
 268                 inode->i_size = 0;
 269                 affs_truncate(inode);
 270         }
 271
 272         invalidate_inode_buffers(inode);
 273         clear_inode(inode);
 274         affs_free_prealloc(inode);
 275         cache_page = (unsigned long)AFFS_I(inode)->i_lc;
 276         if (cache_page) {
 277                 pr_debug("freeing ext cache\n");
 278                 AFFS_I(inode)->i_lc = NULL;
 279                 AFFS_I(inode)->i_ac = NULL;
 280                 free_page(cache_page);
 281         }
 282         affs_brelse(AFFS_I(inode)->i_ext_bh);
 283         AFFS_I(inode)->i_ext_last = ~1;
 284         AFFS_I(inode)->i_ext_bh = NULL;
 285
 286         if (!inode->i_nlink)
 287                 affs_free_block(inode->i_sb, inode->i_ino);
 288 }
 289
 290 struct inode *
 291 affs_new_inode(struct inode *dir)
 292 {
 293         struct super_block      *sb = dir->i_sb;
 294         struct inode            *inode;
 295         u32                      block;
 296         struct buffer_head      *bh;
 297
 298         if (!(inode = new_inode(sb)))
 299                 goto err_inode;
 300
 301         if (!(block = affs_alloc_block(dir, dir->i_ino)))
 302                 goto err_block;
 303
 304         bh = affs_getzeroblk(sb, block);
 305         if (!bh)
 306                 goto err_bh;
 307         mark_buffer_dirty_inode(bh, inode);
 308         affs_brelse(bh);
 309
 310         inode->i_uid     = current_fsuid();
 311         inode->i_gid     = current_fsgid();
 312         inode->i_ino     = block;
 313         set_nlink(inode, 1);
 314         simple_inode_init_ts(inode);
 315         atomic_set(&AFFS_I(inode)->i_opencnt, 0);
 316         AFFS_I(inode)->i_blkcnt = 0;
 317         AFFS_I(inode)->i_lc = NULL;
 318         AFFS_I(inode)->i_lc_size = 0;
 319         AFFS_I(inode)->i_lc_shift = 0;
 320         AFFS_I(inode)->i_lc_mask = 0;
 321         AFFS_I(inode)->i_ac = NULL;
 322         AFFS_I(inode)->i_ext_bh = NULL;
 323         AFFS_I(inode)->mmu_private = 0;
 324         AFFS_I(inode)->i_protect = 0;
 325         AFFS_I(inode)->i_lastalloc = 0;
 326         AFFS_I(inode)->i_pa_cnt = 0;
 327         AFFS_I(inode)->i_extcnt = 1;
 328         AFFS_I(inode)->i_ext_last = ~1;
 329
 330         insert_inode_hash(inode);
 331
 332         return inode;
 333
 334 err_bh:
 335         affs_free_block(sb, block);
 336 err_block:
 337         iput(inode);
 338 err_inode:
 339         return NULL;
 340 }
 341
 342 /*
 343  * Add an entry to a directory. Create the header block
 344  * and insert it into the hash table.
 345  */
 346
 347 int
 348 affs_add_entry(struct inode *dir, struct inode *inode, struct dentry *dentry, s32 type)
 349 {
 350         struct super_block *sb = dir->i_sb;
 351         struct buffer_head *inode_bh = NULL;
 352         struct buffer_head *bh;
 353         u32 block = 0;
 354         int retval;
 355
 356         pr_debug("%s(dir=%lu, inode=%lu, \"%pd\", type=%d)\n", __func__,
 357                  dir->i_ino, inode->i_ino, dentry, type);
 358
 359         retval = -EIO;
 360         bh = affs_bread(sb, inode->i_ino);
 361         if (!bh)
 362                 goto done;
 363
 364         affs_lock_link(inode);
 365         switch (type) {
 366         case ST_LINKFILE:
 367         case ST_LINKDIR:
 368                 retval = -ENOSPC;
 369                 block = affs_alloc_block(dir, dir->i_ino);
 370                 if (!block)
 371                         goto err;
 372                 retval = -EIO;
 373                 inode_bh = bh;
 374                 bh = affs_getzeroblk(sb, block);
 375                 if (!bh)
 376                         goto err;
 377                 break;
 378         default:
 379                 break;
 380         }
 381
 382         AFFS_HEAD(bh)->ptype = cpu_to_be32(T_SHORT);
 383         AFFS_HEAD(bh)->key = cpu_to_be32(bh->b_blocknr);
 384         affs_copy_name(AFFS_TAIL(sb, bh)->name, dentry);
 385         AFFS_TAIL(sb, bh)->stype = cpu_to_be32(type);
 386         AFFS_TAIL(sb, bh)->parent = cpu_to_be32(dir->i_ino);
 387
 388         if (inode_bh) {
 389                 __be32 chain;
 390                 chain = AFFS_TAIL(sb, inode_bh)->link_chain;
 391                 AFFS_TAIL(sb, bh)->original = cpu_to_be32(inode->i_ino);
 392                 AFFS_TAIL(sb, bh)->link_chain = chain;
 393                 AFFS_TAIL(sb, inode_bh)->link_chain = cpu_to_be32(block);
 394                 affs_adjust_checksum(inode_bh, block - be32_to_cpu(chain));
 395                 mark_buffer_dirty_inode(inode_bh, inode);
 396                 set_nlink(inode, 2);
 397                 ihold(inode);
 398         }
 399         affs_fix_checksum(sb, bh);
 400         mark_buffer_dirty_inode(bh, inode);
 401         dentry->d_fsdata = (void *)(long)bh->b_blocknr;
 402
 403         affs_lock_dir(dir);
 404         retval = affs_insert_hash(dir, bh);
 405         mark_buffer_dirty_inode(bh, inode);
 406         affs_unlock_dir(dir);
 407         affs_unlock_link(inode);
 408
 409         d_instantiate(dentry, inode);
 410 done:
 411         affs_brelse(inode_bh);
 412         affs_brelse(bh);
 413         return retval;
 414 err:
 415         if (block)
 416                 affs_free_block(sb, block);
 417         affs_unlock_link(inode);
 418         goto done;
 419 }