[PATCH 3.11 089/121] block: Fix nr_vecs for inline integrity vectors

[Luis Henriques]

3.11.10.5 -stable review patch.  If anyone has any objections, please let me know.

------------------

From: "Martin K. Petersen" <martin.petersen at oracle.com>

commit 087787959ce851d7bbb19f10f6e9241b7f85a3ca upstream.

Commit 9f060e2231ca changed the way we handle allocations for the
integrity vectors. When the vectors are inline there is no associated
slab and consequently bvec_nr_vecs() returns 0. Ensure that we check
against BIP_INLINE_VECS in that case.

Reported-by: David Milburn <dmilburn at redhat.com>
Tested-by: David Milburn <dmilburn at redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen at oracle.com>
Signed-off-by: Jens Axboe <axboe at fb.com>
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 fs/bio-integrity.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/fs/bio-integrity.c b/fs/bio-integrity.c
index 45e944f..8dccf73 100644
--- a/fs/bio-integrity.c
+++ b/fs/bio-integrity.c
@@ -114,6 +114,14 @@ void bio_integrity_free(struct bio *bio)
 }
 EXPORT_SYMBOL(bio_integrity_free);
 
+static inline unsigned int bip_integrity_vecs(struct bio_integrity_payload *bip)
+{
+	if (bip->bip_slab == BIO_POOL_NONE)
+		return BIP_INLINE_VECS;
+
+	return bvec_nr_vecs(bip->bip_slab);
+}
+
 /**
  * bio_integrity_add_page - Attach integrity metadata
  * @bio:	bio to update
@@ -129,7 +137,7 @@ int bio_integrity_add_page(struct bio *bio, struct page *page,
 	struct bio_integrity_payload *bip = bio->bi_integrity;
 	struct bio_vec *iv;
 
-	if (bip->bip_vcnt >= bvec_nr_vecs(bip->bip_slab)) {
+	if (bip->bip_vcnt >= bip_integrity_vecs(bip)) {
 		printk(KERN_ERR "%s: bip_vec full\n", __func__);
 		return 0;
 	}
-- 
1.9.0