From 10fe6ca80d9d25eca9fd6d98eccf6c795532fe96 Mon Sep 17 00:00:00 2001 From: Johannes Thumshirn Date: Wed, 22 May 2019 10:19:02 +0200 Subject: [PATCH] btrfs: don't assume compressed_bio sums to be 4 bytes BTRFS has the implicit assumption that a checksum in compressed_bio is 4 bytes. While this is true for CRC32C, it is not for any other checksum. Change the data type to be a byte array and adjust loop index calculation accordingly. Signed-off-by: Johannes Thumshirn Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/compression.c | 27 +++++++++++++++++---------- fs/btrfs/compression.h | 2 +- fs/btrfs/file-item.c | 2 +- 3 files changed, 19 insertions(+), 12 deletions(-) diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c index a8e551ca8798..92291f266324 100644 --- a/fs/btrfs/compression.c +++ b/fs/btrfs/compression.c @@ -57,12 +57,14 @@ static int check_compressed_csum(struct btrfs_inode *inode, struct compressed_bio *cb, u64 disk_start) { + struct btrfs_fs_info *fs_info = inode->root->fs_info; + const u16 csum_size = btrfs_super_csum_size(fs_info->super_copy); int ret; struct page *page; unsigned long i; char *kaddr; u32 csum; - u32 *cb_sum = &cb->sums; + u8 *cb_sum = cb->sums; if (inode->flags & BTRFS_INODE_NODATASUM) return 0; @@ -76,13 +78,13 @@ static int check_compressed_csum(struct btrfs_inode *inode, btrfs_csum_final(csum, (u8 *)&csum); kunmap_atomic(kaddr); - if (csum != *cb_sum) { + if (memcmp(&csum, cb_sum, csum_size)) { btrfs_print_data_csum_error(inode, disk_start, csum, - *cb_sum, cb->mirror_num); + *(u32 *)cb_sum, cb->mirror_num); ret = -EIO; goto fail; } - cb_sum++; + cb_sum += csum_size; } ret = 0; @@ -536,7 +538,8 @@ blk_status_t btrfs_submit_compressed_read(struct inode *inode, struct bio *bio, struct extent_map *em; blk_status_t ret = BLK_STS_RESOURCE; int faili = 0; - u32 *sums; + const u16 csum_size = btrfs_super_csum_size(fs_info->super_copy); + u8 *sums; em_tree = &BTRFS_I(inode)->extent_tree; @@ -558,7 +561,7 @@ blk_status_t btrfs_submit_compressed_read(struct inode *inode, struct bio *bio, cb->errors = 0; cb->inode = inode; cb->mirror_num = mirror_num; - sums = &cb->sums; + sums = cb->sums; cb->start = em->orig_start; em_len = em->len; @@ -617,6 +620,8 @@ blk_status_t btrfs_submit_compressed_read(struct inode *inode, struct bio *bio, page->mapping = NULL; if (submit || bio_add_page(comp_bio, page, PAGE_SIZE, 0) < PAGE_SIZE) { + unsigned int nr_sectors; + ret = btrfs_bio_wq_end_io(fs_info, comp_bio, BTRFS_WQ_ENDIO_DATA); BUG_ON(ret); /* -ENOMEM */ @@ -631,11 +636,13 @@ blk_status_t btrfs_submit_compressed_read(struct inode *inode, struct bio *bio, if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) { ret = btrfs_lookup_bio_sums(inode, comp_bio, - (u8 *)sums); + sums); BUG_ON(ret); /* -ENOMEM */ } - sums += DIV_ROUND_UP(comp_bio->bi_iter.bi_size, - fs_info->sectorsize); + + nr_sectors = DIV_ROUND_UP(comp_bio->bi_iter.bi_size, + fs_info->sectorsize); + sums += csum_size * nr_sectors; ret = btrfs_map_bio(fs_info, comp_bio, mirror_num, 0); if (ret) { @@ -657,7 +664,7 @@ blk_status_t btrfs_submit_compressed_read(struct inode *inode, struct bio *bio, BUG_ON(ret); /* -ENOMEM */ if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) { - ret = btrfs_lookup_bio_sums(inode, comp_bio, (u8 *) sums); + ret = btrfs_lookup_bio_sums(inode, comp_bio, sums); BUG_ON(ret); /* -ENOMEM */ } diff --git a/fs/btrfs/compression.h b/fs/btrfs/compression.h index 9976fe0f7526..191e5f4e3523 100644 --- a/fs/btrfs/compression.h +++ b/fs/btrfs/compression.h @@ -61,7 +61,7 @@ struct compressed_bio { * the start of a variable length array of checksums only * used by reads */ - u32 sums; + u8 sums[]; }; static inline unsigned int btrfs_compress_type(unsigned int type_level) diff --git a/fs/btrfs/file-item.c b/fs/btrfs/file-item.c index 0464dd4c0579..de89fd1310a6 100644 --- a/fs/btrfs/file-item.c +++ b/fs/btrfs/file-item.c @@ -186,7 +186,7 @@ static blk_status_t __btrfs_lookup_bio_sums(struct inode *inode, struct bio *bio } csum = btrfs_bio->csum; } else { - csum = (u8 *)dst; + csum = dst; } if (bio->bi_iter.bi_size > PAGE_SIZE * 8) -- 2.30.2