dm integrity: fix data corruption due to improper use of bvec_kmap_local
Commit
25058d1c725c ("dm integrity: use bvec_kmap_local in
__journal_read_write") didn't account for __journal_read_write() later
adding the biovec's bv_offset. As such using bvec_kmap_local() caused
the start of the biovec to be skipped.
Trivial test that illustrates data corruption:
# integritysetup format /dev/pmem0
# integritysetup open /dev/pmem0 integrityroot
# mkfs.xfs /dev/mapper/integrityroot
...
bad magic number
bad magic number
Metadata corruption detected at xfs_sb block 0x0/0x1000
libxfs_writebufr: write verifer failed on xfs_sb bno 0x0/0x1000
releasing dirty buffer (bulk) to free list!
Fix this by using kmap_local_page() instead of bvec_kmap_local() in
__journal_read_write().
Fixes:
25058d1c725c ("dm integrity: use bvec_kmap_local in __journal_read_write")
Reported-by: Tony Asleson <tasleson@redhat.com>
Reviewed-by: Heinz Mauelshagen <heinzm@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>