From a3ddbaebc7c9bcdaf0e9bf39780bbad4ff1b569f Mon Sep 17 00:00:00 2001 From: Qu Wenruo Date: Mon, 20 Mar 2023 10:12:52 +0800 Subject: btrfs: scrub: introduce a helper to verify one metadata block The new helper, scrub_verify_one_metadata(), is almost the same as scrub_checksum_tree_block(). The difference is in how we grab the pages from other structures. Signed-off-by: Qu Wenruo Reviewed-by: David Sterba Signed-off-by: David Sterba --- fs/btrfs/scrub.c | 106 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ fs/btrfs/scrub.h | 1 + 2 files changed, 107 insertions(+) (limited to 'fs/btrfs') diff --git a/fs/btrfs/scrub.c b/fs/btrfs/scrub.c index 56f8c54102b0..034d2ad05a92 100644 --- a/fs/btrfs/scrub.c +++ b/fs/btrfs/scrub.c @@ -2159,6 +2159,112 @@ static int scrub_checksum_data(struct scrub_block *sblock) return sblock->checksum_error; } +static struct page *scrub_stripe_get_page(struct scrub_stripe *stripe, int sector_nr) +{ + struct btrfs_fs_info *fs_info = stripe->bg->fs_info; + int page_index = (sector_nr << fs_info->sectorsize_bits) >> PAGE_SHIFT; + + return stripe->pages[page_index]; +} + +static unsigned int scrub_stripe_get_page_offset(struct scrub_stripe *stripe, + int sector_nr) +{ + struct btrfs_fs_info *fs_info = stripe->bg->fs_info; + + return offset_in_page(sector_nr << fs_info->sectorsize_bits); +} + +void scrub_verify_one_metadata(struct scrub_stripe *stripe, int sector_nr) +{ + struct btrfs_fs_info *fs_info = stripe->bg->fs_info; + const u32 sectors_per_tree = fs_info->nodesize >> fs_info->sectorsize_bits; + const u64 logical = stripe->logical + (sector_nr << fs_info->sectorsize_bits); + const struct page *first_page = scrub_stripe_get_page(stripe, sector_nr); + const unsigned int first_off = scrub_stripe_get_page_offset(stripe, sector_nr); + SHASH_DESC_ON_STACK(shash, fs_info->csum_shash); + u8 on_disk_csum[BTRFS_CSUM_SIZE]; + u8 calculated_csum[BTRFS_CSUM_SIZE]; + struct btrfs_header *header; + + /* + * Here we don't have a good way to attach the pages (and subpages) + * to a dummy extent buffer, thus we have to directly grab the members + * from pages. + */ + header = (struct btrfs_header *)(page_address(first_page) + first_off); + memcpy(on_disk_csum, header->csum, fs_info->csum_size); + + if (logical != btrfs_stack_header_bytenr(header)) { + bitmap_set(&stripe->csum_error_bitmap, sector_nr, sectors_per_tree); + bitmap_set(&stripe->error_bitmap, sector_nr, sectors_per_tree); + btrfs_warn_rl(fs_info, + "tree block %llu mirror %u has bad bytenr, has %llu want %llu", + logical, stripe->mirror_num, + btrfs_stack_header_bytenr(header), logical); + return; + } + if (memcmp(header->fsid, fs_info->fs_devices->fsid, BTRFS_FSID_SIZE) != 0) { + bitmap_set(&stripe->meta_error_bitmap, sector_nr, sectors_per_tree); + bitmap_set(&stripe->error_bitmap, sector_nr, sectors_per_tree); + btrfs_warn_rl(fs_info, + "tree block %llu mirror %u has bad fsid, has %pU want %pU", + logical, stripe->mirror_num, + header->fsid, fs_info->fs_devices->fsid); + return; + } + if (memcmp(header->chunk_tree_uuid, fs_info->chunk_tree_uuid, + BTRFS_UUID_SIZE) != 0) { + bitmap_set(&stripe->meta_error_bitmap, sector_nr, sectors_per_tree); + bitmap_set(&stripe->error_bitmap, sector_nr, sectors_per_tree); + btrfs_warn_rl(fs_info, + "tree block %llu mirror %u has bad chunk tree uuid, has %pU want %pU", + logical, stripe->mirror_num, + header->chunk_tree_uuid, fs_info->chunk_tree_uuid); + return; + } + + /* Now check tree block csum. */ + shash->tfm = fs_info->csum_shash; + crypto_shash_init(shash); + crypto_shash_update(shash, page_address(first_page) + first_off + + BTRFS_CSUM_SIZE, fs_info->sectorsize - BTRFS_CSUM_SIZE); + + for (int i = sector_nr + 1; i < sector_nr + sectors_per_tree; i++) { + struct page *page = scrub_stripe_get_page(stripe, i); + unsigned int page_off = scrub_stripe_get_page_offset(stripe, i); + + crypto_shash_update(shash, page_address(page) + page_off, + fs_info->sectorsize); + } + + crypto_shash_final(shash, calculated_csum); + if (memcmp(calculated_csum, on_disk_csum, fs_info->csum_size) != 0) { + bitmap_set(&stripe->meta_error_bitmap, sector_nr, sectors_per_tree); + bitmap_set(&stripe->error_bitmap, sector_nr, sectors_per_tree); + btrfs_warn_rl(fs_info, + "tree block %llu mirror %u has bad csum, has " CSUM_FMT " want " CSUM_FMT, + logical, stripe->mirror_num, + CSUM_FMT_VALUE(fs_info->csum_size, on_disk_csum), + CSUM_FMT_VALUE(fs_info->csum_size, calculated_csum)); + return; + } + if (stripe->sectors[sector_nr].generation != + btrfs_stack_header_generation(header)) { + bitmap_set(&stripe->meta_error_bitmap, sector_nr, sectors_per_tree); + bitmap_set(&stripe->error_bitmap, sector_nr, sectors_per_tree); + btrfs_warn_rl(fs_info, + "tree block %llu mirror %u has bad generation, has %llu want %llu", + logical, stripe->mirror_num, + btrfs_stack_header_generation(header), + stripe->sectors[sector_nr].generation); + return; + } + bitmap_clear(&stripe->error_bitmap, sector_nr, sectors_per_tree); + bitmap_clear(&stripe->csum_error_bitmap, sector_nr, sectors_per_tree); + bitmap_clear(&stripe->meta_error_bitmap, sector_nr, sectors_per_tree); +} + static int scrub_checksum_tree_block(struct scrub_block *sblock) { struct scrub_ctx *sctx = sblock->sctx; diff --git a/fs/btrfs/scrub.h b/fs/btrfs/scrub.h index 27019d86b539..0d8bdc7df89c 100644 --- a/fs/btrfs/scrub.h +++ b/fs/btrfs/scrub.h @@ -24,5 +24,6 @@ int scrub_find_fill_first_stripe(struct btrfs_block_group *bg, struct btrfs_device *dev, u64 physical, int mirror_num, u64 logical_start, u32 logical_len, struct scrub_stripe *stripe); +void scrub_verify_one_metadata(struct scrub_stripe *stripe, int sector_nr); #endif -- cgit v1.2.1