[dm-devel] [PATCH 09/13] block: Add an explicit bio flag for bios that own their bvec

[koverstreet at google.com]

From: Kent Overstreet <koverstreet at google.com>

This is for the new bio splitting code. When we split a bio, if the
split occured on a bvec boundry we reuse the bvec for the new bio. But
that means bio_free() can't free it, hence the explicit flag.

Signed-off-by: Kent Overstreet <koverstreet at google.com>
---
 fs/bio.c                  |    3 ++-
 include/linux/blk_types.h |    1 +
 2 files changed, 3 insertions(+), 1 deletions(-)

diff --git a/fs/bio.c b/fs/bio.c
index ecc9088..3332800 100644
--- a/fs/bio.c
+++ b/fs/bio.c
@@ -234,7 +234,7 @@ void bio_free(struct bio *bio, struct bio_set *bs)
 {
 	void *p;
 
-	if (bio_has_allocated_vec(bio))
+	if (bio_flagged(bio, BIO_HAS_VEC))
 		bvec_free_bs(bs, bio->bi_io_vec, BIO_POOL_IDX(bio));
 
 	if (bio_integrity(bio))
@@ -305,6 +305,7 @@ struct bio *bio_alloc_bioset(gfp_t gfp_mask, int nr_iovecs, struct bio_set *bs)
 			goto err_free;
 
 		nr_iovecs = bvec_nr_vecs(idx);
+		bio->bi_flags |= 1 << BIO_HAS_VEC;
 	}
 out_set:
 	bio->bi_flags |= idx << BIO_POOL_OFFSET;
diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h
index bd9a610..10fca21 100644
--- a/include/linux/blk_types.h
+++ b/include/linux/blk_types.h
@@ -101,6 +101,7 @@ struct bio {
 #define BIO_FS_INTEGRITY 9	/* fs owns integrity data, not block layer */
 #define BIO_QUIET	10	/* Make BIO Quiet */
 #define BIO_MAPPED_INTEGRITY 11/* integrity metadata has been remapped */
+#define BIO_HAS_VEC	12	/* bio_free() should free bvec */
 #define bio_flagged(bio, flag)	((bio)->bi_flags & (1 << (flag)))
 
 /*
-- 
1.7.9.rc2