nagai/kernel
3
0
Fork 0
forked from mirrors/linux
Code Pull requests Activity

btrfs: scrub: introduce a helper to verify one metadata block

Browse source 
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 <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
Qu Wenruo 2023-03-20 10:12:52 +08:00 committed by David Sterba
parent b979547513
commit a3ddbaebc7
2 changed files with 107 additions and 0 deletions
repo.diff.show_diff_stats Download patch file Download diff file Expand all files Collapse all files

106
fs/btrfs/scrub.c
View file

@ -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;

1
fs/btrfs/scrub.h
View file

@ -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