1 // SPDX-License-Identifier: GPL-2.0-only
3 * Copyright (C) 2017-2018 HUAWEI, Inc.
4 * https://www.huawei.com/
5 * Copyright (C) 2021, Alibaba Cloud
7 #include <linux/module.h>
8 #include <linux/buffer_head.h>
9 #include <linux/statfs.h>
10 #include <linux/parser.h>
11 #include <linux/seq_file.h>
12 #include <linux/crc32c.h>
13 #include <linux/fs_context.h>
14 #include <linux/fs_parser.h>
15 #include <linux/dax.h>
16 #include <linux/exportfs.h>
19 #define CREATE_TRACE_POINTS
20 #include <trace/events/erofs.h>
22 static struct kmem_cache *erofs_inode_cachep __read_mostly;
24 void _erofs_err(struct super_block *sb, const char *function,
35 pr_err("(device %s): %s: %pV", sb->s_id, function, &vaf);
39 void _erofs_info(struct super_block *sb, const char *function,
50 pr_info("(device %s): %pV", sb->s_id, &vaf);
54 static int erofs_superblock_csum_verify(struct super_block *sb, void *sbdata)
56 struct erofs_super_block *dsb;
57 u32 expected_crc, crc;
59 dsb = kmemdup(sbdata + EROFS_SUPER_OFFSET,
60 EROFS_BLKSIZ - EROFS_SUPER_OFFSET, GFP_KERNEL);
64 expected_crc = le32_to_cpu(dsb->checksum);
66 /* to allow for x86 boot sectors and other oddities. */
67 crc = crc32c(~0, dsb, EROFS_BLKSIZ - EROFS_SUPER_OFFSET);
70 if (crc != expected_crc) {
71 erofs_err(sb, "invalid checksum 0x%08x, 0x%08x expected",
78 static void erofs_inode_init_once(void *ptr)
80 struct erofs_inode *vi = ptr;
82 inode_init_once(&vi->vfs_inode);
85 static struct inode *erofs_alloc_inode(struct super_block *sb)
87 struct erofs_inode *vi =
88 alloc_inode_sb(sb, erofs_inode_cachep, GFP_KERNEL);
93 /* zero out everything except vfs_inode */
94 memset(vi, 0, offsetof(struct erofs_inode, vfs_inode));
95 return &vi->vfs_inode;
98 static void erofs_free_inode(struct inode *inode)
100 struct erofs_inode *vi = EROFS_I(inode);
102 /* be careful of RCU symlink path */
103 if (inode->i_op == &erofs_fast_symlink_iops)
104 kfree(inode->i_link);
105 kfree(vi->xattr_shared_xattrs);
107 kmem_cache_free(erofs_inode_cachep, vi);
110 static bool check_layout_compatibility(struct super_block *sb,
111 struct erofs_super_block *dsb)
113 const unsigned int feature = le32_to_cpu(dsb->feature_incompat);
115 EROFS_SB(sb)->feature_incompat = feature;
117 /* check if current kernel meets all mandatory requirements */
118 if (feature & (~EROFS_ALL_FEATURE_INCOMPAT)) {
120 "unidentified incompatible feature %x, please upgrade kernel version",
121 feature & ~EROFS_ALL_FEATURE_INCOMPAT);
127 #ifdef CONFIG_EROFS_FS_ZIP
128 /* read variable-sized metadata, offset will be aligned by 4-byte */
129 static void *erofs_read_metadata(struct super_block *sb, struct erofs_buf *buf,
130 erofs_off_t *offset, int *lengthp)
135 *offset = round_up(*offset, 4);
136 ptr = erofs_read_metabuf(buf, sb, erofs_blknr(*offset), EROFS_KMAP);
140 len = le16_to_cpu(*(__le16 *)&ptr[erofs_blkoff(*offset)]);
143 buffer = kmalloc(len, GFP_KERNEL);
145 return ERR_PTR(-ENOMEM);
146 *offset += sizeof(__le16);
149 for (i = 0; i < len; i += cnt) {
150 cnt = min(EROFS_BLKSIZ - (int)erofs_blkoff(*offset), len - i);
151 ptr = erofs_read_metabuf(buf, sb, erofs_blknr(*offset),
157 memcpy(buffer + i, ptr + erofs_blkoff(*offset), cnt);
163 static int erofs_load_compr_cfgs(struct super_block *sb,
164 struct erofs_super_block *dsb)
166 struct erofs_sb_info *sbi = EROFS_SB(sb);
167 struct erofs_buf buf = __EROFS_BUF_INITIALIZER;
168 unsigned int algs, alg;
172 sbi->available_compr_algs = le16_to_cpu(dsb->u1.available_compr_algs);
173 if (sbi->available_compr_algs & ~Z_EROFS_ALL_COMPR_ALGS) {
174 erofs_err(sb, "try to load compressed fs with unsupported algorithms %x",
175 sbi->available_compr_algs & ~Z_EROFS_ALL_COMPR_ALGS);
179 offset = EROFS_SUPER_OFFSET + sbi->sb_size;
181 for (algs = sbi->available_compr_algs; algs; algs >>= 1, ++alg) {
187 data = erofs_read_metadata(sb, &buf, &offset, &size);
194 case Z_EROFS_COMPRESSION_LZ4:
195 ret = z_erofs_load_lz4_config(sb, dsb, data, size);
197 case Z_EROFS_COMPRESSION_LZMA:
198 ret = z_erofs_load_lzma_config(sb, dsb, data, size);
208 erofs_put_metabuf(&buf);
212 static int erofs_load_compr_cfgs(struct super_block *sb,
213 struct erofs_super_block *dsb)
215 if (dsb->u1.available_compr_algs) {
216 erofs_err(sb, "try to load compressed fs when compression is disabled");
223 static int erofs_init_device(struct erofs_buf *buf, struct super_block *sb,
224 struct erofs_device_info *dif, erofs_off_t *pos)
226 struct erofs_sb_info *sbi = EROFS_SB(sb);
227 struct erofs_deviceslot *dis;
228 struct block_device *bdev;
232 ptr = erofs_read_metabuf(buf, sb, erofs_blknr(*pos), EROFS_KMAP);
235 dis = ptr + erofs_blkoff(*pos);
239 erofs_err(sb, "empty device tag @ pos %llu", *pos);
242 dif->path = kmemdup_nul(dis->tag, sizeof(dis->tag), GFP_KERNEL);
247 if (erofs_is_fscache_mode(sb)) {
248 ret = erofs_fscache_register_cookie(sb, &dif->fscache,
253 bdev = blkdev_get_by_path(dif->path, FMODE_READ | FMODE_EXCL,
256 return PTR_ERR(bdev);
258 dif->dax_dev = fs_dax_get_by_bdev(bdev, &dif->dax_part_off,
262 dif->blocks = le32_to_cpu(dis->blocks);
263 dif->mapped_blkaddr = le32_to_cpu(dis->mapped_blkaddr);
264 sbi->total_blocks += dif->blocks;
265 *pos += EROFS_DEVT_SLOT_SIZE;
269 static int erofs_scan_devices(struct super_block *sb,
270 struct erofs_super_block *dsb)
272 struct erofs_sb_info *sbi = EROFS_SB(sb);
273 unsigned int ondisk_extradevs;
275 struct erofs_buf buf = __EROFS_BUF_INITIALIZER;
276 struct erofs_device_info *dif;
279 sbi->total_blocks = sbi->primarydevice_blocks;
280 if (!erofs_sb_has_device_table(sbi))
281 ondisk_extradevs = 0;
283 ondisk_extradevs = le16_to_cpu(dsb->extra_devices);
285 if (sbi->devs->extra_devices &&
286 ondisk_extradevs != sbi->devs->extra_devices) {
287 erofs_err(sb, "extra devices don't match (ondisk %u, given %u)",
288 ondisk_extradevs, sbi->devs->extra_devices);
291 if (!ondisk_extradevs)
294 sbi->device_id_mask = roundup_pow_of_two(ondisk_extradevs + 1) - 1;
295 pos = le16_to_cpu(dsb->devt_slotoff) * EROFS_DEVT_SLOT_SIZE;
296 down_read(&sbi->devs->rwsem);
297 if (sbi->devs->extra_devices) {
298 idr_for_each_entry(&sbi->devs->tree, dif, id) {
299 err = erofs_init_device(&buf, sb, dif, &pos);
304 for (id = 0; id < ondisk_extradevs; id++) {
305 dif = kzalloc(sizeof(*dif), GFP_KERNEL);
311 err = idr_alloc(&sbi->devs->tree, dif, 0, 0, GFP_KERNEL);
316 ++sbi->devs->extra_devices;
318 err = erofs_init_device(&buf, sb, dif, &pos);
323 up_read(&sbi->devs->rwsem);
324 erofs_put_metabuf(&buf);
328 static int erofs_read_superblock(struct super_block *sb)
330 struct erofs_sb_info *sbi;
331 struct erofs_buf buf = __EROFS_BUF_INITIALIZER;
332 struct erofs_super_block *dsb;
333 unsigned int blkszbits;
337 data = erofs_read_metabuf(&buf, sb, 0, EROFS_KMAP);
339 erofs_err(sb, "cannot read erofs superblock");
340 return PTR_ERR(data);
344 dsb = (struct erofs_super_block *)(data + EROFS_SUPER_OFFSET);
347 if (le32_to_cpu(dsb->magic) != EROFS_SUPER_MAGIC_V1) {
348 erofs_err(sb, "cannot find valid erofs superblock");
352 sbi->feature_compat = le32_to_cpu(dsb->feature_compat);
353 if (erofs_sb_has_sb_chksum(sbi)) {
354 ret = erofs_superblock_csum_verify(sb, data);
360 blkszbits = dsb->blkszbits;
361 /* 9(512 bytes) + LOG_SECTORS_PER_BLOCK == LOG_BLOCK_SIZE */
362 if (blkszbits != LOG_BLOCK_SIZE) {
363 erofs_err(sb, "blkszbits %u isn't supported on this platform",
368 if (!check_layout_compatibility(sb, dsb))
371 sbi->sb_size = 128 + dsb->sb_extslots * EROFS_SB_EXTSLOT_SIZE;
372 if (sbi->sb_size > EROFS_BLKSIZ) {
373 erofs_err(sb, "invalid sb_extslots %u (more than a fs block)",
377 sbi->primarydevice_blocks = le32_to_cpu(dsb->blocks);
378 sbi->meta_blkaddr = le32_to_cpu(dsb->meta_blkaddr);
379 #ifdef CONFIG_EROFS_FS_XATTR
380 sbi->xattr_blkaddr = le32_to_cpu(dsb->xattr_blkaddr);
382 sbi->islotbits = ilog2(sizeof(struct erofs_inode_compact));
383 sbi->root_nid = le16_to_cpu(dsb->root_nid);
384 sbi->inos = le64_to_cpu(dsb->inos);
386 sbi->build_time = le64_to_cpu(dsb->build_time);
387 sbi->build_time_nsec = le32_to_cpu(dsb->build_time_nsec);
389 memcpy(&sb->s_uuid, dsb->uuid, sizeof(dsb->uuid));
391 ret = strscpy(sbi->volume_name, dsb->volume_name,
392 sizeof(dsb->volume_name));
393 if (ret < 0) { /* -E2BIG */
394 erofs_err(sb, "bad volume name without NIL terminator");
399 /* parse on-disk compression configurations */
400 if (erofs_sb_has_compr_cfgs(sbi))
401 ret = erofs_load_compr_cfgs(sb, dsb);
403 ret = z_erofs_load_lz4_config(sb, dsb, NULL, 0);
407 /* handle multiple devices */
408 ret = erofs_scan_devices(sb, dsb);
410 if (erofs_sb_has_ztailpacking(sbi))
411 erofs_info(sb, "EXPERIMENTAL compressed inline data feature in use. Use at your own risk!");
412 if (erofs_is_fscache_mode(sb))
413 erofs_info(sb, "EXPERIMENTAL fscache-based on-demand read feature in use. Use at your own risk!");
415 erofs_put_metabuf(&buf);
419 /* set up default EROFS parameters */
420 static void erofs_default_options(struct erofs_fs_context *ctx)
422 #ifdef CONFIG_EROFS_FS_ZIP
423 ctx->opt.cache_strategy = EROFS_ZIP_CACHE_READAROUND;
424 ctx->opt.max_sync_decompress_pages = 3;
425 ctx->opt.sync_decompress = EROFS_SYNC_DECOMPRESS_AUTO;
427 #ifdef CONFIG_EROFS_FS_XATTR
428 set_opt(&ctx->opt, XATTR_USER);
430 #ifdef CONFIG_EROFS_FS_POSIX_ACL
431 set_opt(&ctx->opt, POSIX_ACL);
446 static const struct constant_table erofs_param_cache_strategy[] = {
447 {"disabled", EROFS_ZIP_CACHE_DISABLED},
448 {"readahead", EROFS_ZIP_CACHE_READAHEAD},
449 {"readaround", EROFS_ZIP_CACHE_READAROUND},
453 static const struct constant_table erofs_dax_param_enums[] = {
454 {"always", EROFS_MOUNT_DAX_ALWAYS},
455 {"never", EROFS_MOUNT_DAX_NEVER},
459 static const struct fs_parameter_spec erofs_fs_parameters[] = {
460 fsparam_flag_no("user_xattr", Opt_user_xattr),
461 fsparam_flag_no("acl", Opt_acl),
462 fsparam_enum("cache_strategy", Opt_cache_strategy,
463 erofs_param_cache_strategy),
464 fsparam_flag("dax", Opt_dax),
465 fsparam_enum("dax", Opt_dax_enum, erofs_dax_param_enums),
466 fsparam_string("device", Opt_device),
467 fsparam_string("fsid", Opt_fsid),
471 static bool erofs_fc_set_dax_mode(struct fs_context *fc, unsigned int mode)
474 struct erofs_fs_context *ctx = fc->fs_private;
477 case EROFS_MOUNT_DAX_ALWAYS:
478 warnfc(fc, "DAX enabled. Warning: EXPERIMENTAL, use at your own risk");
479 set_opt(&ctx->opt, DAX_ALWAYS);
480 clear_opt(&ctx->opt, DAX_NEVER);
482 case EROFS_MOUNT_DAX_NEVER:
483 set_opt(&ctx->opt, DAX_NEVER);
484 clear_opt(&ctx->opt, DAX_ALWAYS);
491 errorfc(fc, "dax options not supported");
496 static int erofs_fc_parse_param(struct fs_context *fc,
497 struct fs_parameter *param)
499 struct erofs_fs_context *ctx = fc->fs_private;
500 struct fs_parse_result result;
501 struct erofs_device_info *dif;
504 opt = fs_parse(fc, erofs_fs_parameters, param, &result);
510 #ifdef CONFIG_EROFS_FS_XATTR
512 set_opt(&ctx->opt, XATTR_USER);
514 clear_opt(&ctx->opt, XATTR_USER);
516 errorfc(fc, "{,no}user_xattr options not supported");
520 #ifdef CONFIG_EROFS_FS_POSIX_ACL
522 set_opt(&ctx->opt, POSIX_ACL);
524 clear_opt(&ctx->opt, POSIX_ACL);
526 errorfc(fc, "{,no}acl options not supported");
529 case Opt_cache_strategy:
530 #ifdef CONFIG_EROFS_FS_ZIP
531 ctx->opt.cache_strategy = result.uint_32;
533 errorfc(fc, "compression not supported, cache_strategy ignored");
537 if (!erofs_fc_set_dax_mode(fc, EROFS_MOUNT_DAX_ALWAYS))
541 if (!erofs_fc_set_dax_mode(fc, result.uint_32))
545 dif = kzalloc(sizeof(*dif), GFP_KERNEL);
548 dif->path = kstrdup(param->string, GFP_KERNEL);
553 down_write(&ctx->devs->rwsem);
554 ret = idr_alloc(&ctx->devs->tree, dif, 0, 0, GFP_KERNEL);
555 up_write(&ctx->devs->rwsem);
561 ++ctx->devs->extra_devices;
564 #ifdef CONFIG_EROFS_FS_ONDEMAND
565 kfree(ctx->opt.fsid);
566 ctx->opt.fsid = kstrdup(param->string, GFP_KERNEL);
570 errorfc(fc, "fsid option not supported");
579 #ifdef CONFIG_EROFS_FS_ZIP
580 static const struct address_space_operations managed_cache_aops;
582 static bool erofs_managed_cache_release_folio(struct folio *folio, gfp_t gfp)
585 struct address_space *const mapping = folio->mapping;
587 DBG_BUGON(!folio_test_locked(folio));
588 DBG_BUGON(mapping->a_ops != &managed_cache_aops);
590 if (folio_test_private(folio))
591 ret = erofs_try_to_free_cached_page(&folio->page);
597 * It will be called only on inode eviction. In case that there are still some
598 * decompression requests in progress, wait with rescheduling for a bit here.
599 * We could introduce an extra locking instead but it seems unnecessary.
601 static void erofs_managed_cache_invalidate_folio(struct folio *folio,
602 size_t offset, size_t length)
604 const size_t stop = length + offset;
606 DBG_BUGON(!folio_test_locked(folio));
608 /* Check for potential overflow in debug mode */
609 DBG_BUGON(stop > folio_size(folio) || stop < length);
611 if (offset == 0 && stop == folio_size(folio))
612 while (!erofs_managed_cache_release_folio(folio, GFP_NOFS))
616 static const struct address_space_operations managed_cache_aops = {
617 .release_folio = erofs_managed_cache_release_folio,
618 .invalidate_folio = erofs_managed_cache_invalidate_folio,
621 static int erofs_init_managed_cache(struct super_block *sb)
623 struct erofs_sb_info *const sbi = EROFS_SB(sb);
624 struct inode *const inode = new_inode(sb);
630 inode->i_size = OFFSET_MAX;
632 inode->i_mapping->a_ops = &managed_cache_aops;
633 mapping_set_gfp_mask(inode->i_mapping, GFP_NOFS);
634 sbi->managed_cache = inode;
638 static int erofs_init_managed_cache(struct super_block *sb) { return 0; }
641 static struct inode *erofs_nfs_get_inode(struct super_block *sb,
642 u64 ino, u32 generation)
644 return erofs_iget(sb, ino, false);
647 static struct dentry *erofs_fh_to_dentry(struct super_block *sb,
648 struct fid *fid, int fh_len, int fh_type)
650 return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
651 erofs_nfs_get_inode);
654 static struct dentry *erofs_fh_to_parent(struct super_block *sb,
655 struct fid *fid, int fh_len, int fh_type)
657 return generic_fh_to_parent(sb, fid, fh_len, fh_type,
658 erofs_nfs_get_inode);
661 static struct dentry *erofs_get_parent(struct dentry *child)
667 err = erofs_namei(d_inode(child), &dotdot_name, &nid, &d_type);
670 return d_obtain_alias(erofs_iget(child->d_sb, nid, d_type == FT_DIR));
673 static const struct export_operations erofs_export_ops = {
674 .fh_to_dentry = erofs_fh_to_dentry,
675 .fh_to_parent = erofs_fh_to_parent,
676 .get_parent = erofs_get_parent,
679 static int erofs_fc_fill_super(struct super_block *sb, struct fs_context *fc)
682 struct erofs_sb_info *sbi;
683 struct erofs_fs_context *ctx = fc->fs_private;
686 sb->s_magic = EROFS_SUPER_MAGIC;
687 sb->s_flags |= SB_RDONLY | SB_NOATIME;
688 sb->s_maxbytes = MAX_LFS_FILESIZE;
689 sb->s_op = &erofs_sops;
691 sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
697 ctx->opt.fsid = NULL;
698 sbi->devs = ctx->devs;
701 if (erofs_is_fscache_mode(sb)) {
702 sb->s_blocksize = EROFS_BLKSIZ;
703 sb->s_blocksize_bits = LOG_BLOCK_SIZE;
705 err = erofs_fscache_register_fs(sb);
709 err = erofs_fscache_register_cookie(sb, &sbi->s_fscache,
710 sbi->opt.fsid, true);
714 err = super_setup_bdi(sb);
718 if (!sb_set_blocksize(sb, EROFS_BLKSIZ)) {
719 erofs_err(sb, "failed to set erofs blksize");
723 sbi->dax_dev = fs_dax_get_by_bdev(sb->s_bdev,
728 err = erofs_read_superblock(sb);
732 if (test_opt(&sbi->opt, DAX_ALWAYS)) {
733 BUILD_BUG_ON(EROFS_BLKSIZ != PAGE_SIZE);
736 errorfc(fc, "DAX unsupported by block device. Turning off DAX.");
737 clear_opt(&sbi->opt, DAX_ALWAYS);
742 sb->s_xattr = erofs_xattr_handlers;
743 sb->s_export_op = &erofs_export_ops;
745 if (test_opt(&sbi->opt, POSIX_ACL))
746 sb->s_flags |= SB_POSIXACL;
748 sb->s_flags &= ~SB_POSIXACL;
750 #ifdef CONFIG_EROFS_FS_ZIP
751 xa_init(&sbi->managed_pslots);
754 /* get the root inode */
755 inode = erofs_iget(sb, ROOT_NID(sbi), true);
757 return PTR_ERR(inode);
759 if (!S_ISDIR(inode->i_mode)) {
760 erofs_err(sb, "rootino(nid %llu) is not a directory(i_mode %o)",
761 ROOT_NID(sbi), inode->i_mode);
766 sb->s_root = d_make_root(inode);
770 erofs_shrinker_register(sb);
771 /* sb->s_umount is already locked, SB_ACTIVE and SB_BORN are not set */
772 err = erofs_init_managed_cache(sb);
776 err = erofs_register_sysfs(sb);
780 erofs_info(sb, "mounted with root inode @ nid %llu.", ROOT_NID(sbi));
784 static int erofs_fc_get_tree(struct fs_context *fc)
786 struct erofs_fs_context *ctx = fc->fs_private;
788 if (IS_ENABLED(CONFIG_EROFS_FS_ONDEMAND) && ctx->opt.fsid)
789 return get_tree_nodev(fc, erofs_fc_fill_super);
791 return get_tree_bdev(fc, erofs_fc_fill_super);
794 static int erofs_fc_reconfigure(struct fs_context *fc)
796 struct super_block *sb = fc->root->d_sb;
797 struct erofs_sb_info *sbi = EROFS_SB(sb);
798 struct erofs_fs_context *ctx = fc->fs_private;
800 DBG_BUGON(!sb_rdonly(sb));
802 if (test_opt(&ctx->opt, POSIX_ACL))
803 fc->sb_flags |= SB_POSIXACL;
805 fc->sb_flags &= ~SB_POSIXACL;
809 fc->sb_flags |= SB_RDONLY;
813 static int erofs_release_device_info(int id, void *ptr, void *data)
815 struct erofs_device_info *dif = ptr;
817 fs_put_dax(dif->dax_dev, NULL);
819 blkdev_put(dif->bdev, FMODE_READ | FMODE_EXCL);
820 erofs_fscache_unregister_cookie(&dif->fscache);
826 static void erofs_free_dev_context(struct erofs_dev_context *devs)
830 idr_for_each(&devs->tree, &erofs_release_device_info, NULL);
831 idr_destroy(&devs->tree);
835 static void erofs_fc_free(struct fs_context *fc)
837 struct erofs_fs_context *ctx = fc->fs_private;
839 erofs_free_dev_context(ctx->devs);
840 kfree(ctx->opt.fsid);
844 static const struct fs_context_operations erofs_context_ops = {
845 .parse_param = erofs_fc_parse_param,
846 .get_tree = erofs_fc_get_tree,
847 .reconfigure = erofs_fc_reconfigure,
848 .free = erofs_fc_free,
851 static int erofs_init_fs_context(struct fs_context *fc)
853 struct erofs_fs_context *ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
857 ctx->devs = kzalloc(sizeof(struct erofs_dev_context), GFP_KERNEL);
862 fc->fs_private = ctx;
864 idr_init(&ctx->devs->tree);
865 init_rwsem(&ctx->devs->rwsem);
866 erofs_default_options(ctx);
867 fc->ops = &erofs_context_ops;
872 * could be triggered after deactivate_locked_super()
873 * is called, thus including umount and failed to initialize.
875 static void erofs_kill_sb(struct super_block *sb)
877 struct erofs_sb_info *sbi;
879 WARN_ON(sb->s_magic != EROFS_SUPER_MAGIC);
881 if (erofs_is_fscache_mode(sb))
882 generic_shutdown_super(sb);
884 kill_block_super(sb);
890 erofs_free_dev_context(sbi->devs);
891 fs_put_dax(sbi->dax_dev, NULL);
892 erofs_fscache_unregister_cookie(&sbi->s_fscache);
893 erofs_fscache_unregister_fs(sb);
894 kfree(sbi->opt.fsid);
896 sb->s_fs_info = NULL;
899 /* called when ->s_root is non-NULL */
900 static void erofs_put_super(struct super_block *sb)
902 struct erofs_sb_info *const sbi = EROFS_SB(sb);
906 erofs_unregister_sysfs(sb);
907 erofs_shrinker_unregister(sb);
908 #ifdef CONFIG_EROFS_FS_ZIP
909 iput(sbi->managed_cache);
910 sbi->managed_cache = NULL;
912 erofs_fscache_unregister_cookie(&sbi->s_fscache);
915 static struct file_system_type erofs_fs_type = {
916 .owner = THIS_MODULE,
918 .init_fs_context = erofs_init_fs_context,
919 .kill_sb = erofs_kill_sb,
920 .fs_flags = FS_REQUIRES_DEV | FS_ALLOW_IDMAP,
922 MODULE_ALIAS_FS("erofs");
924 static int __init erofs_module_init(void)
928 erofs_check_ondisk_layout_definitions();
930 erofs_inode_cachep = kmem_cache_create("erofs_inode",
931 sizeof(struct erofs_inode), 0,
932 SLAB_RECLAIM_ACCOUNT,
933 erofs_inode_init_once);
934 if (!erofs_inode_cachep) {
939 err = erofs_init_shrinker();
943 err = z_erofs_lzma_init();
947 erofs_pcpubuf_init();
948 err = z_erofs_init_zip_subsystem();
952 err = erofs_init_sysfs();
956 err = register_filesystem(&erofs_fs_type);
965 z_erofs_exit_zip_subsystem();
969 erofs_exit_shrinker();
971 kmem_cache_destroy(erofs_inode_cachep);
976 static void __exit erofs_module_exit(void)
978 unregister_filesystem(&erofs_fs_type);
980 /* Ensure all RCU free inodes / pclusters are safe to be destroyed. */
984 z_erofs_exit_zip_subsystem();
986 erofs_exit_shrinker();
987 kmem_cache_destroy(erofs_inode_cachep);
988 erofs_pcpubuf_exit();
991 /* get filesystem statistics */
992 static int erofs_statfs(struct dentry *dentry, struct kstatfs *buf)
994 struct super_block *sb = dentry->d_sb;
995 struct erofs_sb_info *sbi = EROFS_SB(sb);
998 if (!erofs_is_fscache_mode(sb))
999 id = huge_encode_dev(sb->s_bdev->bd_dev);
1001 buf->f_type = sb->s_magic;
1002 buf->f_bsize = EROFS_BLKSIZ;
1003 buf->f_blocks = sbi->total_blocks;
1004 buf->f_bfree = buf->f_bavail = 0;
1006 buf->f_files = ULLONG_MAX;
1007 buf->f_ffree = ULLONG_MAX - sbi->inos;
1009 buf->f_namelen = EROFS_NAME_LEN;
1011 buf->f_fsid = u64_to_fsid(id);
1015 static int erofs_show_options(struct seq_file *seq, struct dentry *root)
1017 struct erofs_sb_info *sbi = EROFS_SB(root->d_sb);
1018 struct erofs_mount_opts *opt = &sbi->opt;
1020 #ifdef CONFIG_EROFS_FS_XATTR
1021 if (test_opt(opt, XATTR_USER))
1022 seq_puts(seq, ",user_xattr");
1024 seq_puts(seq, ",nouser_xattr");
1026 #ifdef CONFIG_EROFS_FS_POSIX_ACL
1027 if (test_opt(opt, POSIX_ACL))
1028 seq_puts(seq, ",acl");
1030 seq_puts(seq, ",noacl");
1032 #ifdef CONFIG_EROFS_FS_ZIP
1033 if (opt->cache_strategy == EROFS_ZIP_CACHE_DISABLED)
1034 seq_puts(seq, ",cache_strategy=disabled");
1035 else if (opt->cache_strategy == EROFS_ZIP_CACHE_READAHEAD)
1036 seq_puts(seq, ",cache_strategy=readahead");
1037 else if (opt->cache_strategy == EROFS_ZIP_CACHE_READAROUND)
1038 seq_puts(seq, ",cache_strategy=readaround");
1040 if (test_opt(opt, DAX_ALWAYS))
1041 seq_puts(seq, ",dax=always");
1042 if (test_opt(opt, DAX_NEVER))
1043 seq_puts(seq, ",dax=never");
1044 #ifdef CONFIG_EROFS_FS_ONDEMAND
1046 seq_printf(seq, ",fsid=%s", opt->fsid);
1051 const struct super_operations erofs_sops = {
1052 .put_super = erofs_put_super,
1053 .alloc_inode = erofs_alloc_inode,
1054 .free_inode = erofs_free_inode,
1055 .statfs = erofs_statfs,
1056 .show_options = erofs_show_options,
1059 module_init(erofs_module_init);
1060 module_exit(erofs_module_exit);
1062 MODULE_DESCRIPTION("Enhanced ROM File System");
1063 MODULE_AUTHOR("Gao Xiang, Chao Yu, Miao Xie, CONSUMER BG, HUAWEI Inc.");
1064 MODULE_LICENSE("GPL");