bio-integrity: Add explicit field for owner of bip_buf

This was the only real user of BIO_CLONED, which didn't have very clear
semantics. Convert to its own flag so we can get rid of BIO_CLONED.

Signed-off-by: Kent Overstreet <koverstreet@google.com>
CC: Jens Axboe <axboe@kernel.dk>
CC: Martin K. Petersen <martin.petersen@oracle.com>
diff --git a/fs/bio-integrity.c b/fs/bio-integrity.c
index ca7b02d..8fb42916 100644
--- a/fs/bio-integrity.c
+++ b/fs/bio-integrity.c
@@ -97,9 +97,7 @@
 	struct bio_integrity_payload *bip = bio->bi_integrity;
 	struct bio_set *bs = bio->bi_pool;
 
-	/* A cloned bio doesn't own the integrity metadata */
-	if (!bio_flagged(bio, BIO_CLONED) && !bio_flagged(bio, BIO_FS_INTEGRITY)
-	    && bip->bip_buf != NULL)
+	if (bip->bip_owns_buf)
 		kfree(bip->bip_buf);
 
 	if (bs) {
@@ -386,6 +384,7 @@
 		return -EIO;
 	}
 
+	bip->bip_owns_buf = 1;
 	bip->bip_buf = buf;
 	bip->bip_size = len;
 	bip->bip_sector = bio->bi_sector;
diff --git a/include/linux/bio.h b/include/linux/bio.h
index 794bcd0..ef24466 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -187,6 +187,7 @@
 	unsigned short		bip_slab;	/* slab the bip came from */
 	unsigned short		bip_vcnt;	/* # of integrity bio_vecs */
 	unsigned short		bip_idx;	/* current bip_vec index */
+	unsigned		bip_owns_buf:1;	/* should free bip_buf */
 
 	struct work_struct	bip_work;	/* I/O completion */