diff options
| author | Gao Xiang | 2021-03-29 09:23:07 +0800 |
|---|---|---|
| committer | Gao Xiang | 2021-03-29 10:24:58 +0800 |
| commit | 46249cded18ac0c4ffb7b177219510a133a51c00 (patch) | |
| tree | 71682f8e22563f0c126c81d6848b276f3284f239 | |
| parent | 5d50538fc567c6f3692dec1825fb38c5a0884d93 (diff) | |
erofs: introduce on-disk lz4 fs configurations
Introduce z_erofs_lz4_cfgs to store all lz4 configurations.
Currently it's only max_distance, but will be used for new
features later.
Link: https://lore.kernel.org/r/20210329012308.28743-4-hsiangkao@aol.com
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Gao Xiang <hsiangkao@redhat.com>
| -rw-r--r-- | fs/erofs/decompressor.c | 15 | ||||
| -rw-r--r-- | fs/erofs/erofs_fs.h | 6 | ||||
| -rw-r--r-- | fs/erofs/internal.h | 8 | ||||
| -rw-r--r-- | fs/erofs/super.c | 2 |
4 files changed, 25 insertions, 6 deletions
diff --git a/fs/erofs/decompressor.c b/fs/erofs/decompressor.c index 93411e9df9b6..97538ff24a19 100644 --- a/fs/erofs/decompressor.c +++ b/fs/erofs/decompressor.c @@ -29,9 +29,20 @@ struct z_erofs_decompressor { }; int z_erofs_load_lz4_config(struct super_block *sb, - struct erofs_super_block *dsb) + struct erofs_super_block *dsb, + struct z_erofs_lz4_cfgs *lz4, int size) { - u16 distance = le16_to_cpu(dsb->lz4_max_distance); + u16 distance; + + if (lz4) { + if (size < sizeof(struct z_erofs_lz4_cfgs)) { + erofs_err(sb, "invalid lz4 cfgs, size=%u", size); + return -EINVAL; + } + distance = le16_to_cpu(lz4->max_distance); + } else { + distance = le16_to_cpu(dsb->lz4_max_distance); + } EROFS_SB(sb)->lz4.max_distance_pages = distance ? DIV_ROUND_UP(distance, PAGE_SIZE) + 1 : diff --git a/fs/erofs/erofs_fs.h b/fs/erofs/erofs_fs.h index dc7cc79410df..700597e9c810 100644 --- a/fs/erofs/erofs_fs.h +++ b/fs/erofs/erofs_fs.h @@ -200,6 +200,12 @@ enum { Z_EROFS_COMPRESSION_MAX }; +/* 14 bytes (+ length field = 16 bytes) */ +struct z_erofs_lz4_cfgs { + __le16 max_distance; + u8 reserved[12]; +} __packed; + /* * bit 0 : COMPACTED_2B indexes (0 - off; 1 - on) * e.g. for 4k logical cluster size, 4B if compacted 2B is off; diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h index 875b2ebf2af9..b02fc64fcece 100644 --- a/fs/erofs/internal.h +++ b/fs/erofs/internal.h @@ -439,7 +439,8 @@ int erofs_try_to_free_all_cached_pages(struct erofs_sb_info *sbi, int erofs_try_to_free_cached_page(struct address_space *mapping, struct page *page); int z_erofs_load_lz4_config(struct super_block *sb, - struct erofs_super_block *dsb); + struct erofs_super_block *dsb, + struct z_erofs_lz4_cfgs *lz4, int len); #else static inline void erofs_shrinker_register(struct super_block *sb) {} static inline void erofs_shrinker_unregister(struct super_block *sb) {} @@ -448,9 +449,10 @@ static inline void erofs_exit_shrinker(void) {} static inline int z_erofs_init_zip_subsystem(void) { return 0; } static inline void z_erofs_exit_zip_subsystem(void) {} static inline int z_erofs_load_lz4_config(struct super_block *sb, - struct erofs_super_block *dsb) + struct erofs_super_block *dsb, + struct z_erofs_lz4_cfgs *lz4, int len) { - if (dsb->lz4_max_distance) { + if (lz4 || dsb->lz4_max_distance) { erofs_err(sb, "lz4 algorithm isn't enabled"); return -EINVAL; } diff --git a/fs/erofs/super.c b/fs/erofs/super.c index 3212e4f73f85..1ca8da3f2125 100644 --- a/fs/erofs/super.c +++ b/fs/erofs/super.c @@ -189,7 +189,7 @@ static int erofs_read_superblock(struct super_block *sb) } /* parse on-disk compression configurations */ - ret = z_erofs_load_lz4_config(sb, dsb); + ret = z_erofs_load_lz4_config(sb, dsb, NULL, 0); out: kunmap(page); put_page(page); |