From: Mikulas Patocka mpatocka@redhat.com
[ Upstream commit b4d78cfeb30476239cf08f4f40afc095c173d6e3 ]
It is possible to set up dm-integrity with smaller sector size than the logical sector size of the underlying device. In this situation, dm-integrity guarantees that the outgoing bios have the same alignment as incoming bios (so, if you create a filesystem with 4k block size, dm-integrity would send 4k-aligned bios to the underlying device).
This guarantee was broken when integrity_recheck was implemented. integrity_recheck sends bio that is aligned to ic->sectors_per_block. So if we set up integrity with 512-byte sector size on a device with logical block size 4k, we would be sending unaligned bio. This triggered a bug in one of our internal tests.
This commit fixes it by determining the actual alignment of the incoming bio and then makes sure that the outgoing bio in integrity_recheck has the same alignment.
Fixes: c88f5e553fe3 ("dm-integrity: recheck the integrity tag after a failure") Signed-off-by: Mikulas Patocka mpatocka@redhat.com Signed-off-by: Mike Snitzer snitzer@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/md/dm-integrity.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-)
diff --git a/drivers/md/dm-integrity.c b/drivers/md/dm-integrity.c index 92bed6ce17931..47cf1ab34941f 100644 --- a/drivers/md/dm-integrity.c +++ b/drivers/md/dm-integrity.c @@ -1699,7 +1699,6 @@ static noinline void integrity_recheck(struct dm_integrity_io *dio, char *checks struct bio_vec bv; sector_t sector, logical_sector, area, offset; struct page *page; - void *buffer;
get_area_and_offset(ic, dio->range.logical_sector, &area, &offset); dio->metadata_block = get_metadata_sector_and_offset(ic, area, offset, @@ -1708,13 +1707,14 @@ static noinline void integrity_recheck(struct dm_integrity_io *dio, char *checks logical_sector = dio->range.logical_sector;
page = mempool_alloc(&ic->recheck_pool, GFP_NOIO); - buffer = page_to_virt(page);
__bio_for_each_segment(bv, bio, iter, dio->bio_details.bi_iter) { unsigned pos = 0;
do { + sector_t alignment; char *mem; + char *buffer = page_to_virt(page); int r; struct dm_io_request io_req; struct dm_io_region io_loc; @@ -1727,6 +1727,14 @@ static noinline void integrity_recheck(struct dm_integrity_io *dio, char *checks io_loc.sector = sector; io_loc.count = ic->sectors_per_block;
+ /* Align the bio to logical block size */ + alignment = dio->range.logical_sector | bio_sectors(bio) | (PAGE_SIZE >> SECTOR_SHIFT); + alignment &= -alignment; + io_loc.sector = round_down(io_loc.sector, alignment); + io_loc.count += sector - io_loc.sector; + buffer += (sector - io_loc.sector) << SECTOR_SHIFT; + io_loc.count = round_up(io_loc.count, alignment); + r = dm_io(&io_req, 1, &io_loc, NULL, IOPRIO_DEFAULT); if (unlikely(r)) { dio->bi_status = errno_to_blk_status(r);