dm integrity: don't re-write metadata if discarding same blocks

If we discard already discarded blocks we do not need to write discard
pattern to the metadata, because it is already there.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
This commit is contained in:
Mikulas Patocka 2021-04-27 11:57:06 -04:00 committed by Mike Snitzer
parent f99a8e4373
commit a9c0fda4c0

View File

@ -1429,8 +1429,10 @@ static int dm_integrity_rw_tag(struct dm_integrity_c *ic, unsigned char *tag, se
if (op == TAG_READ) {
memcpy(tag, dp, to_copy);
} else if (op == TAG_WRITE) {
memcpy(dp, tag, to_copy);
dm_bufio_mark_partial_buffer_dirty(b, *metadata_offset, *metadata_offset + to_copy);
if (memcmp(dp, tag, to_copy)) {
memcpy(dp, tag, to_copy);
dm_bufio_mark_partial_buffer_dirty(b, *metadata_offset, *metadata_offset + to_copy);
}
} else {
/* e.g.: op == TAG_CMP */