diff options
| -rw-r--r-- | fs/erofs/decompressor.c | 21 | ||||
| -rw-r--r-- | fs/erofs/erofs_fs.h | 4 | ||||
| -rw-r--r-- | fs/erofs/internal.h | 19 | ||||
| -rw-r--r-- | fs/erofs/super.c | 4 |
4 files changed, 42 insertions, 6 deletions
diff --git a/fs/erofs/decompressor.c b/fs/erofs/decompressor.c index 80e8871aef71..93411e9df9b6 100644 --- a/fs/erofs/decompressor.c +++ b/fs/erofs/decompressor.c @@ -28,6 +28,17 @@ struct z_erofs_decompressor { char *name; }; +int z_erofs_load_lz4_config(struct super_block *sb, + struct erofs_super_block *dsb) +{ + u16 distance = le16_to_cpu(dsb->lz4_max_distance); + + EROFS_SB(sb)->lz4.max_distance_pages = distance ? + DIV_ROUND_UP(distance, PAGE_SIZE) + 1 : + LZ4_MAX_DISTANCE_PAGES; + return 0; +} + static int z_erofs_lz4_prepare_destpages(struct z_erofs_decompress_req *rq, struct list_head *pagepool) { @@ -36,6 +47,8 @@ static int z_erofs_lz4_prepare_destpages(struct z_erofs_decompress_req *rq, struct page *availables[LZ4_MAX_DISTANCE_PAGES] = { NULL }; unsigned long bounced[DIV_ROUND_UP(LZ4_MAX_DISTANCE_PAGES, BITS_PER_LONG)] = { 0 }; + unsigned int lz4_max_distance_pages = + EROFS_SB(rq->sb)->lz4.max_distance_pages; void *kaddr = NULL; unsigned int i, j, top; @@ -44,14 +57,14 @@ static int z_erofs_lz4_prepare_destpages(struct z_erofs_decompress_req *rq, struct page *const page = rq->out[i]; struct page *victim; - if (j >= LZ4_MAX_DISTANCE_PAGES) + if (j >= lz4_max_distance_pages) j = 0; /* 'valid' bounced can only be tested after a complete round */ if (test_bit(j, bounced)) { - DBG_BUGON(i < LZ4_MAX_DISTANCE_PAGES); - DBG_BUGON(top >= LZ4_MAX_DISTANCE_PAGES); - availables[top++] = rq->out[i - LZ4_MAX_DISTANCE_PAGES]; + DBG_BUGON(i < lz4_max_distance_pages); + DBG_BUGON(top >= lz4_max_distance_pages); + availables[top++] = rq->out[i - lz4_max_distance_pages]; } if (page) { diff --git a/fs/erofs/erofs_fs.h b/fs/erofs/erofs_fs.h index e8d04d808fa6..dc7cc79410df 100644 --- a/fs/erofs/erofs_fs.h +++ b/fs/erofs/erofs_fs.h @@ -39,7 +39,9 @@ struct erofs_super_block { __u8 uuid[16]; /* 128-bit uuid for volume */ __u8 volume_name[16]; /* volume name */ __le32 feature_incompat; - __u8 reserved2[44]; + /* customized lz4 sliding window size instead of 64k by default */ + __le16 lz4_max_distance; + __u8 reserved2[42]; }; /* diff --git a/fs/erofs/internal.h b/fs/erofs/internal.h index a148a039cf67..875b2ebf2af9 100644 --- a/fs/erofs/internal.h +++ b/fs/erofs/internal.h @@ -59,6 +59,12 @@ struct erofs_fs_context { unsigned int mount_opt; }; +/* all filesystem-wide lz4 configurations */ +struct erofs_sb_lz4_info { + /* # of pages needed for EROFS lz4 rolling decompression */ + u16 max_distance_pages; +}; + struct erofs_sb_info { #ifdef CONFIG_EROFS_FS_ZIP /* list for all registered superblocks, mainly for shrinker */ @@ -72,6 +78,8 @@ struct erofs_sb_info { /* pseudo inode to manage cached pages */ struct inode *managed_cache; + + struct erofs_sb_lz4_info lz4; #endif /* CONFIG_EROFS_FS_ZIP */ u32 blocks; u32 meta_blkaddr; @@ -430,6 +438,8 @@ int erofs_try_to_free_all_cached_pages(struct erofs_sb_info *sbi, struct erofs_workgroup *egrp); 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); #else static inline void erofs_shrinker_register(struct super_block *sb) {} static inline void erofs_shrinker_unregister(struct super_block *sb) {} @@ -437,6 +447,15 @@ static inline int erofs_init_shrinker(void) { return 0; } 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) +{ + if (dsb->lz4_max_distance) { + erofs_err(sb, "lz4 algorithm isn't enabled"); + return -EINVAL; + } + return 0; +} #endif /* !CONFIG_EROFS_FS_ZIP */ #define EFSCORRUPTED EUCLEAN /* Filesystem is corrupted */ diff --git a/fs/erofs/super.c b/fs/erofs/super.c index 991b99eaf22a..3212e4f73f85 100644 --- a/fs/erofs/super.c +++ b/fs/erofs/super.c @@ -187,7 +187,9 @@ static int erofs_read_superblock(struct super_block *sb) ret = -EFSCORRUPTED; goto out; } - ret = 0; + + /* parse on-disk compression configurations */ + ret = z_erofs_load_lz4_config(sb, dsb); out: kunmap(page); put_page(page); |