[PATCH v8 6/8] block: Kill bi_destructor
From: Kent Overstreet
Date: Wed Sep 05 2012 - 16:28:33 EST
Now that we've got generic code for freeing bios allocated from bio
pools, this isn't needed anymore.
This patch also makes bio_free() static, since without bi_destructor
there should be no need for it to be called anywhere else.
While we're at it, since bio_free() is now only called from one place,
refactor it a bit and pull out __bio_free() for bio_reset() to use.
v5: Switch to BIO_KMALLOC_POOL ((void *)~0), per Boaz
v6: BIO_KMALLOC_POOL now NULL, drop bio_free's EXPORT_SYMBOL
v7: No #define BIO_KMALLOC_POOL anymore
Signed-off-by: Kent Overstreet <koverstreet@xxxxxxxxxx>
CC: Jens Axboe <axboe@xxxxxxxxx>
---
Documentation/block/biodoc.txt | 5 ----
block/blk-core.c | 2 +-
fs/bio.c | 64 +++++++++++++++++-------------------------
include/linux/bio.h | 1 -
include/linux/blk_types.h | 3 --
5 files changed, 27 insertions(+), 48 deletions(-)
diff --git a/Documentation/block/biodoc.txt b/Documentation/block/biodoc.txt
index e418dc0..8df5e8e 100644
--- a/Documentation/block/biodoc.txt
+++ b/Documentation/block/biodoc.txt
@@ -465,7 +465,6 @@ struct bio {
bio_end_io_t *bi_end_io; /* bi_end_io (bio) */
atomic_t bi_cnt; /* pin count: free when it hits zero */
void *bi_private;
- bio_destructor_t *bi_destructor; /* bi_destructor (bio) */
};
With this multipage bio design:
@@ -647,10 +646,6 @@ for a non-clone bio. There are the 6 pools setup for different size biovecs,
so bio_alloc(gfp_mask, nr_iovecs) will allocate a vec_list of the
given size from these slabs.
-The bi_destructor() routine takes into account the possibility of the bio
-having originated from a different source (see later discussions on
-n/w to block transfers and kvec_cb)
-
The bio_get() routine may be used to hold an extra reference on a bio prior
to i/o submission, if the bio fields are likely to be accessed after the
i/o is issued (since the bio may otherwise get freed in case i/o completion
diff --git a/block/blk-core.c b/block/blk-core.c
index 95c4935..b776cc9 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -2807,7 +2807,7 @@ int blk_rq_prep_clone(struct request *rq, struct request *rq_src,
free_and_out:
if (bio)
- bio_free(bio, bs);
+ bio_put(bio);
blk_rq_unprep_clone(rq);
return -ENOMEM;
diff --git a/fs/bio.c b/fs/bio.c
index 208141f..d807fe2 100644
--- a/fs/bio.c
+++ b/fs/bio.c
@@ -233,26 +233,37 @@ fallback:
return bvl;
}
-void bio_free(struct bio *bio, struct bio_set *bs)
+static void __bio_free(struct bio *bio)
{
- void *p;
-
- if (bio_has_allocated_vec(bio))
- bvec_free_bs(bs, bio->bi_io_vec, BIO_POOL_IDX(bio));
+ bio_disassociate_task(bio);
if (bio_integrity(bio))
bio_integrity_free(bio);
+}
- /*
- * If we have front padding, adjust the bio pointer before freeing
- */
- p = bio;
- if (bs->front_pad)
+static void bio_free(struct bio *bio)
+{
+ struct bio_set *bs = bio->bi_pool;
+ void *p;
+
+ __bio_free(bio);
+
+ if (bs) {
+ if (bio_has_allocated_vec(bio))
+ bvec_free_bs(bs, bio->bi_io_vec, BIO_POOL_IDX(bio));
+
+ /*
+ * If we have front padding, adjust the bio pointer before freeing
+ */
+ p = bio;
p -= bs->front_pad;
- mempool_free(p, bs->bio_pool);
+ mempool_free(p, bs->bio_pool);
+ } else {
+ /* Bio was allocated by bio_kmalloc() */
+ kfree(bio);
+ }
}
-EXPORT_SYMBOL(bio_free);
void bio_init(struct bio *bio)
{
@@ -266,10 +277,7 @@ void bio_reset(struct bio *bio)
{
unsigned long flags = bio->bi_flags & (~0UL << BIO_RESET_BITS);
- if (bio_integrity(bio))
- bio_integrity_free(bio, bio->bi_pool);
-
- bio_disassociate_task(bio);
+ __bio_free(bio);
memset(bio, 0, BIO_RESET_BYTES);
bio->bi_flags = flags|(1 << BIO_UPTODATE);
@@ -352,13 +360,6 @@ struct bio *bio_alloc(gfp_t gfp_mask, unsigned int nr_iovecs)
}
EXPORT_SYMBOL(bio_alloc);
-static void bio_kmalloc_destructor(struct bio *bio)
-{
- if (bio_integrity(bio))
- bio_integrity_free(bio);
- kfree(bio);
-}
-
/**
* bio_kmalloc - allocate a bio for I/O using kmalloc()
* @gfp_mask: the GFP_ mask given to the slab allocator
@@ -385,7 +386,6 @@ struct bio *bio_kmalloc(gfp_t gfp_mask, unsigned int nr_iovecs)
bio->bi_flags |= BIO_POOL_NONE << BIO_POOL_OFFSET;
bio->bi_max_vecs = nr_iovecs;
bio->bi_io_vec = bio->bi_inline_vecs;
- bio->bi_destructor = bio_kmalloc_destructor;
return bio;
}
@@ -421,20 +421,8 @@ void bio_put(struct bio *bio)
/*
* last put frees it
*/
- if (atomic_dec_and_test(&bio->bi_cnt)) {
- bio_disassociate_task(bio);
- bio->bi_next = NULL;
-
- /*
- * This if statement is temporary - bi_pool is replacing
- * bi_destructor, but bi_destructor will be taken out in another
- * patch.
- */
- if (bio->bi_pool)
- bio_free(bio, bio->bi_pool);
- else
- bio->bi_destructor(bio);
- }
+ if (atomic_dec_and_test(&bio->bi_cnt))
+ bio_free(bio);
}
EXPORT_SYMBOL(bio_put);
diff --git a/include/linux/bio.h b/include/linux/bio.h
index 76f6c25..04944c9 100644
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -216,7 +216,6 @@ extern struct bio *bio_alloc(gfp_t, unsigned int);
extern struct bio *bio_kmalloc(gfp_t, unsigned int);
extern struct bio *bio_alloc_bioset(gfp_t, int, struct bio_set *);
extern void bio_put(struct bio *);
-extern void bio_free(struct bio *, struct bio_set *);
extern void bio_endio(struct bio *, int);
struct request_queue;
diff --git a/include/linux/blk_types.h b/include/linux/blk_types.h
index 1b607c2..3eefbb2 100644
--- a/include/linux/blk_types.h
+++ b/include/linux/blk_types.h
@@ -84,11 +84,8 @@ struct bio {
struct bio_vec *bi_io_vec; /* the actual vec list */
- /* If bi_pool is non NULL, bi_destructor is not called */
struct bio_set *bi_pool;
- bio_destructor_t *bi_destructor; /* destructor */
-
/*
* We can inline a number of vecs at the end of the bio, to avoid
* double allocations for a small number of bio_vecs. This member
--
1.7.12
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