[PATCH 11/17] block: factor out helper for bio allocation from cache

Kanchan Joshi
2022-03-08T15:49:43Z

Factor the code to pull out bio_from_cache helper which is not tied to
kiocb. This is prep patch.

Signed-off-by: Kanchan Joshi <joshi.k@samsung.com>
---
block/bio.c | 43 ++++++++++++++++++++++++++-----------------
include/linux/bio.h | 1 +
2 files changed, 27 insertions(+), 17 deletions(-)

diff --git a/block/bio.c b/block/bio.c
index 4312a8085396..5e12c6bd43d3 100644
--- a/block/bio.c
+++ b/block/bio.c
@@ -1705,27 +1705,12 @@ int bioset_init_from_src(struct bio_set *bs, struct bio_set *src)
}
EXPORT_SYMBOL(bioset_init_from_src);

-/**
- * bio_alloc_kiocb - Allocate a bio from bio_set based on kiocb
- * @kiocb: kiocb describing the IO
- * @nr_vecs: number of iovecs to pre-allocate
- * @bs: bio_set to allocate from
- *
- * Description:
- * Like @bio_alloc_bioset, but pass in the kiocb. The kiocb is only
- * used to check if we should dip into the per-cpu bio_set allocation
- * cache. The allocation uses GFP_KERNEL internally. On return, the
- * bio is marked BIO_PERCPU_CACHEABLE, and the final put of the bio
- * MUST be done from process context, not hard/soft IRQ.
- *
- */
-struct bio *bio_alloc_kiocb(struct kiocb *kiocb, unsigned short nr_vecs,
- struct bio_set *bs)
+struct bio *bio_from_cache(unsigned short nr_vecs, struct bio_set *bs)
{
struct bio_alloc_cache *cache;
struct bio *bio;

- if (!(kiocb->ki_flags & IOCB_ALLOC_CACHE) || nr_vecs > BIO_INLINE_VECS)
+ if (nr_vecs > BIO_INLINE_VECS)
return bio_alloc_bioset(GFP_KERNEL, nr_vecs, bs);

cache = per_cpu_ptr(bs->cache, get_cpu());
@@ -1744,6 +1729,30 @@ struct bio *bio_alloc_kiocb(struct kiocb *kiocb, unsigned short nr_vecs,
bio_set_flag(bio, BIO_PERCPU_CACHE);
return bio;
}
+EXPORT_SYMBOL_GPL(bio_from_cache);
+
+/**
+ * bio_alloc_kiocb - Allocate a bio from bio_set based on kiocb
+ * @kiocb: kiocb describing the IO
+ * @nr_vecs: number of iovecs to pre-allocate
+ * @bs: bio_set to allocate from
+ *
+ * Description:
+ * Like @bio_alloc_bioset, but pass in the kiocb. The kiocb is only
+ * used to check if we should dip into the per-cpu bio_set allocation
+ * cache. The allocation uses GFP_KERNEL internally. On return, the
+ * bio is marked BIO_PERCPU_CACHEABLE, and the final put of the bio
+ * MUST be done from process context, not hard/soft IRQ.
+ *
+ */
+struct bio *bio_alloc_kiocb(struct kiocb *kiocb, unsigned short nr_vecs,
+ struct bio_set *bs)
+{
+ if (!(kiocb->ki_flags & IOCB_ALLOC_CACHE))
+ return bio_alloc_bioset(GFP_KERNEL, nr_vecs, bs);
+
+ return bio_from_cache(nr_vecs, bs);
+}
EXPORT_SYMBOL_GPL(bio_alloc_kiocb);

static int __init init_bio(void)
diff --git a/include/linux/bio.h b/include/linux/bio.h
index 117d7f248ac9..3216401f75b0 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -409,6 +409,7 @@ struct bio *bio_alloc_bioset(gfp_t gfp, unsigned short nr_iovecs,
struct bio_set *bs);
struct bio *bio_alloc_kiocb(struct kiocb *kiocb, unsigned short nr_vecs,
struct bio_set *bs);
+struct bio *bio_from_cache(unsigned short nr_vecs, struct bio_set *bs);
struct bio *bio_kmalloc(gfp_t gfp_mask, unsigned short nr_iovecs);
extern void bio_put(struct bio *);

--
2.25.1