[PATCH v6 16/20] dm-crypt: check if adding pages to clone bio fails

Check if adding pages to clone bio fails and if it does retry with
reclaim. This mirrors the behaviour of page allocation in
crypt_alloc_buffer().

This way we can mark bio_add_pages as __must_check.

Reviewed-by: Damien Le Moal <redacted>
Signed-off-by: Johannes Thumshirn <redacted>
---
 drivers/md/dm-crypt.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index 8b47b913ee83..0dd231e61757 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c

@@ -1693,7 +1693,10 @@ static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned int size)
 
 		len = (remaining_size > PAGE_SIZE) ? PAGE_SIZE : remaining_size;
 
-		bio_add_page(clone, page, len, 0);
+		if (!bio_add_page(clone, page, len, 0)) {
+			WARN_ONCE(1, "Adding page to bio failed\n");
+			return NULL;
+		}
 
 		remaining_size -= len;
 	}

-- 
2.40.1