From e9307e3deb52603c4f742624fa4799c7996422d8 Mon Sep 17 00:00:00 2001
From: Mike Snitzer <snitzer@kernel.org>
Date: Thu, 4 Aug 2022 13:37:53 -0400
Subject: [PATCH] dm verity: only copy bvec_iter in verity_verify_io if
in_tasklet
Git-commit: e9307e3deb52603c4f742624fa4799c7996422d8
Patch-mainline: v6.0-rc1
References: jsc#PED-2765
Avoid extra bvec_iter copy unless it is needed to allow retrying
verification, that failed from a tasklet, from a workqueue.
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Coly Li <colyli@suse.de>
---
drivers/md/dm-verity-target.c | 25 ++++++++++++++++---------
1 file changed, 16 insertions(+), 9 deletions(-)
diff --git a/drivers/md/dm-verity-target.c b/drivers/md/dm-verity-target.c
index 5a4ee3292853..a56e254214fa 100644
--- a/drivers/md/dm-verity-target.c
+++ b/drivers/md/dm-verity-target.c
@@ -501,15 +501,22 @@ static int verity_verify_io(struct dm_verity_io *io)
#if defined(CONFIG_DM_VERITY_FEC)
struct bvec_iter start;
#endif
- /*
- * Copy the iterator in case we need to restart verification in a
- * work-queue.
- */
- struct bvec_iter iter_copy = io->iter;
+ struct bvec_iter iter_copy;
+ struct bvec_iter *iter;
struct crypto_wait wait;
struct bio *bio = dm_bio_from_per_bio_data(io, v->ti->per_io_data_size);
unsigned int b;
+ if (static_branch_unlikely(&use_tasklet_enabled) && io->in_tasklet) {
+ /*
+ * Copy the iterator in case we need to restart
+ * verification in a work-queue.
+ */
+ iter_copy = io->iter;
+ iter = &iter_copy;
+ } else
+ iter = &io->iter;
+
for (b = 0; b < io->n_blocks; b++) {
int r;
sector_t cur_block = io->block + b;
@@ -517,7 +524,7 @@ static int verity_verify_io(struct dm_verity_io *io)
if (v->validated_blocks &&
likely(test_bit(cur_block, v->validated_blocks))) {
- verity_bv_skip_block(v, io, &iter_copy);
+ verity_bv_skip_block(v, io, iter);
continue;
}
@@ -532,7 +539,7 @@ static int verity_verify_io(struct dm_verity_io *io)
* If we expect a zero block, don't validate, just
* return zeros.
*/
- r = verity_for_bv_block(v, io, &iter_copy,
+ r = verity_for_bv_block(v, io, iter,
verity_bv_zero);
if (unlikely(r < 0))
return r;
@@ -546,9 +553,9 @@ static int verity_verify_io(struct dm_verity_io *io)
#if defined(CONFIG_DM_VERITY_FEC)
if (verity_fec_is_enabled(v))
- start = iter_copy;
+ start = *iter;
#endif
- r = verity_for_io_block(v, io, &iter_copy, &wait);
+ r = verity_for_io_block(v, io, iter, &wait);
if (unlikely(r < 0))
return r;
--
2.35.3