diff options
Diffstat (limited to 'fs/erofs/super.c')
| -rw-r--r-- | fs/erofs/super.c | 148 |
1 files changed, 146 insertions, 2 deletions
diff --git a/fs/erofs/super.c b/fs/erofs/super.c index d5a6b9b888a5..bbf3bbd908e0 100644 --- a/fs/erofs/super.c +++ b/fs/erofs/super.c @@ -122,6 +122,136 @@ static bool check_layout_compatibility(struct super_block *sb, return true; } +#ifdef CONFIG_EROFS_FS_ZIP +/* read variable-sized metadata, offset will be aligned by 4-byte */ +static void *erofs_read_metadata(struct super_block *sb, struct page **pagep, + erofs_off_t *offset, int *lengthp) +{ + struct page *page = *pagep; + u8 *buffer, *ptr; + int len, i, cnt; + erofs_blk_t blk; + + *offset = round_up(*offset, 4); + blk = erofs_blknr(*offset); + + if (!page || page->index != blk) { + if (page) { + unlock_page(page); + put_page(page); + } + page = erofs_get_meta_page(sb, blk); + if (IS_ERR(page)) + goto err_nullpage; + } + + ptr = kmap(page); + len = le16_to_cpu(*(__le16 *)&ptr[erofs_blkoff(*offset)]); + if (!len) + len = U16_MAX + 1; + buffer = kmalloc(len, GFP_KERNEL); + if (!buffer) { + buffer = ERR_PTR(-ENOMEM); + goto out; + } + *offset += sizeof(__le16); + *lengthp = len; + + for (i = 0; i < len; i += cnt) { + cnt = min(EROFS_BLKSIZ - (int)erofs_blkoff(*offset), len - i); + blk = erofs_blknr(*offset); + + if (!page || page->index != blk) { + if (page) { + kunmap(page); + unlock_page(page); + put_page(page); + } + page = erofs_get_meta_page(sb, blk); + if (IS_ERR(page)) { + kfree(buffer); + goto err_nullpage; + } + ptr = kmap(page); + } + memcpy(buffer + i, ptr + erofs_blkoff(*offset), cnt); + *offset += cnt; + } +out: + kunmap(page); + *pagep = page; + return buffer; +err_nullpage: + *pagep = NULL; + return page; +} + +static int erofs_load_compr_cfgs(struct super_block *sb, + struct erofs_super_block *dsb) +{ + struct erofs_sb_info *sbi; + struct page *page; + unsigned int algs, alg; + erofs_off_t offset; + int size, ret; + + sbi = EROFS_SB(sb); + sbi->available_compr_algs = le16_to_cpu(dsb->u1.available_compr_algs); + + if (sbi->available_compr_algs & ~Z_EROFS_ALL_COMPR_ALGS) { + erofs_err(sb, "try to load compressed fs with unsupported algorithms %x", + sbi->available_compr_algs & ~Z_EROFS_ALL_COMPR_ALGS); + return -EINVAL; + } + + offset = EROFS_SUPER_OFFSET + sbi->sb_size; + page = NULL; + alg = 0; + ret = 0; + + for (algs = sbi->available_compr_algs; algs; algs >>= 1, ++alg) { + void *data; + + if (!(algs & 1)) + continue; + + data = erofs_read_metadata(sb, &page, &offset, &size); + if (IS_ERR(data)) { + ret = PTR_ERR(data); + goto err; + } + + switch (alg) { + case Z_EROFS_COMPRESSION_LZ4: + ret = z_erofs_load_lz4_config(sb, dsb, data, size); + break; + default: + DBG_BUGON(1); + ret = -EFAULT; + } + kfree(data); + if (ret) + goto err; + } +err: + if (page) { + unlock_page(page); + put_page(page); + } + return ret; +} +#else +static int erofs_load_compr_cfgs(struct super_block *sb, + struct erofs_super_block *dsb) +{ + if (dsb->u1.available_compr_algs) { + erofs_err(sb, "try to load compressed fs when compression is disabled"); + return -EINVAL; + } + return 0; +} +#endif + static int erofs_read_superblock(struct super_block *sb) { struct erofs_sb_info *sbi; @@ -149,7 +279,7 @@ static int erofs_read_superblock(struct super_block *sb) } sbi->feature_compat = le32_to_cpu(dsb->feature_compat); - if (sbi->feature_compat & EROFS_FEATURE_COMPAT_SB_CHKSUM) { + if (erofs_sb_has_sb_chksum(sbi)) { ret = erofs_superblock_csum_verify(sb, data); if (ret) goto out; @@ -166,6 +296,12 @@ static int erofs_read_superblock(struct super_block *sb) if (!check_layout_compatibility(sb, dsb)) goto out; + sbi->sb_size = 128 + dsb->sb_extslots * EROFS_SB_EXTSLOT_SIZE; + if (sbi->sb_size > EROFS_BLKSIZ) { + erofs_err(sb, "invalid sb_extslots %u (more than a fs block)", + sbi->sb_size); + goto out; + } sbi->blocks = le32_to_cpu(dsb->blocks); sbi->meta_blkaddr = le32_to_cpu(dsb->meta_blkaddr); #ifdef CONFIG_EROFS_FS_XATTR @@ -187,7 +323,12 @@ static int erofs_read_superblock(struct super_block *sb) ret = -EFSCORRUPTED; goto out; } - ret = 0; + + /* parse on-disk compression configurations */ + if (erofs_sb_has_compr_cfgs(sbi)) + ret = erofs_load_compr_cfgs(sb, dsb); + else + ret = z_erofs_load_lz4_config(sb, dsb, NULL, 0); out: kunmap(page); put_page(page); @@ -200,6 +341,7 @@ static void erofs_default_options(struct erofs_fs_context *ctx) #ifdef CONFIG_EROFS_FS_ZIP ctx->cache_strategy = EROFS_ZIP_CACHE_READAROUND; ctx->max_sync_decompress_pages = 3; + ctx->readahead_sync_decompress = false; #endif #ifdef CONFIG_EROFS_FS_XATTR set_opt(ctx, XATTR_USER); @@ -513,6 +655,7 @@ static int __init erofs_module_init(void) if (err) goto shrinker_err; + erofs_pcpubuf_init(); err = z_erofs_init_zip_subsystem(); if (err) goto zip_err; @@ -542,6 +685,7 @@ static void __exit erofs_module_exit(void) /* Ensure all RCU free inodes are safe before cache is destroyed. */ rcu_barrier(); kmem_cache_destroy(erofs_inode_cachep); + erofs_pcpubuf_exit(); } /* get filesystem statistics */ |