Commit 917a38c7 authored by Kent Overstreet's avatar Kent Overstreet Committed by Jens Axboe
Browse files

block: Add bioset_init()/bioset_exit() 



Similarly to mempool_init()/mempool_exit(), take a pointer indirection
out of allocation/freeing by allowing biosets to be embedded in other
structs.

Signed-off-by: default avatarKent Overstreet <kent.overstreet@gmail.com>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 8aa6ba2f

block/bio.c

+65 −28
Original line number Diff line number Diff line
@@ -1856,51 +1856,51 @@ int biovec_init_pool(mempool_t *pool, int pool_entries) 
	return mempool_init_slab_pool(pool, pool_entries, bp->slab);

}



void bioset_free(struct bio_set *bs)

/*

 * bioset_exit - exit a bioset initialized with bioset_init()

 *

 * May be called on a zeroed but uninitialized bioset (i.e. allocated with

 * kzalloc()).

 */

void bioset_exit(struct bio_set *bs)

{

	if (bs->rescue_workqueue)

		destroy_workqueue(bs->rescue_workqueue);

	bs->rescue_workqueue = NULL;



	mempool_exit(&bs->bio_pool);

	mempool_exit(&bs->bvec_pool);



	bioset_integrity_free(bs);

	if (bs->bio_slab)

		bio_put_slab(bs);

	bs->bio_slab = NULL;

}

EXPORT_SYMBOL(bioset_exit);



void bioset_free(struct bio_set *bs)

{

	bioset_exit(bs);

	kfree(bs);

}

EXPORT_SYMBOL(bioset_free);



/**

 * bioset_create  - Create a bio_set

 * bioset_init - Initialize a bio_set

 * @pool_size:	Number of bio and bio_vecs to cache in the mempool

 * @front_pad:	Number of bytes to allocate in front of the returned bio

 * @flags:	Flags to modify behavior, currently %BIOSET_NEED_BVECS

 *              and %BIOSET_NEED_RESCUER

 *

 * Description:

 *    Set up a bio_set to be used with @bio_alloc_bioset. Allows the caller

 *    to ask for a number of bytes to be allocated in front of the bio.

 *    Front pad allocation is useful for embedding the bio inside

 *    another structure, to avoid allocating extra data to go with the bio.

 *    Note that the bio must be embedded at the END of that structure always,

 *    or things will break badly.

 *    If %BIOSET_NEED_BVECS is set in @flags, a separate pool will be allocated

 *    for allocating iovecs.  This pool is not needed e.g. for bio_clone_fast().

 *    If %BIOSET_NEED_RESCUER is set, a workqueue is created which can be used to

 *    dispatch queued requests when the mempool runs out of space.

 *

 * Similar to bioset_create(), but initializes a passed-in bioset instead of

 * separately allocating it.

 */

struct bio_set *bioset_create(unsigned int pool_size,

int bioset_init(struct bio_set *bs,

		unsigned int pool_size,

		unsigned int front_pad,

		int flags)

{

	unsigned int back_pad = BIO_INLINE_VECS * sizeof(struct bio_vec);

	struct bio_set *bs;



	bs = kzalloc(sizeof(*bs), GFP_KERNEL);

	if (!bs)

		return NULL;



	bs->front_pad = front_pad;
@@ -1909,10 +1909,8 @@ struct bio_set *bioset_create(unsigned int pool_size, 
	INIT_WORK(&bs->rescue_work, bio_alloc_rescue);



	bs->bio_slab = bio_find_or_create_slab(front_pad + back_pad);

	if (!bs->bio_slab) {

		kfree(bs);

		return NULL;

	}

	if (!bs->bio_slab)

		return -ENOMEM;



	if (mempool_init_slab_pool(&bs->bio_pool, pool_size, bs->bio_slab))

		goto bad;
@@ -1922,17 +1920,56 @@ struct bio_set *bioset_create(unsigned int pool_size, 
		goto bad;



	if (!(flags & BIOSET_NEED_RESCUER))

		return bs;

		return 0;



	bs->rescue_workqueue = alloc_workqueue("bioset", WQ_MEM_RECLAIM, 0);

	if (!bs->rescue_workqueue)

		goto bad;



	return bs;

	return 0;

bad:

	bioset_free(bs);

	bioset_exit(bs);

	return -ENOMEM;

}

EXPORT_SYMBOL(bioset_init);



/**

 * bioset_create  - Create a bio_set

 * @pool_size:	Number of bio and bio_vecs to cache in the mempool

 * @front_pad:	Number of bytes to allocate in front of the returned bio

 * @flags:	Flags to modify behavior, currently %BIOSET_NEED_BVECS

 *              and %BIOSET_NEED_RESCUER

 *

 * Description:

 *    Set up a bio_set to be used with @bio_alloc_bioset. Allows the caller

 *    to ask for a number of bytes to be allocated in front of the bio.

 *    Front pad allocation is useful for embedding the bio inside

 *    another structure, to avoid allocating extra data to go with the bio.

 *    Note that the bio must be embedded at the END of that structure always,

 *    or things will break badly.

 *    If %BIOSET_NEED_BVECS is set in @flags, a separate pool will be allocated

 *    for allocating iovecs.  This pool is not needed e.g. for bio_clone_fast().

 *    If %BIOSET_NEED_RESCUER is set, a workqueue is created which can be used to

 *    dispatch queued requests when the mempool runs out of space.

 *

 */

struct bio_set *bioset_create(unsigned int pool_size,

			      unsigned int front_pad,

			      int flags)

{

	struct bio_set *bs;



	bs = kzalloc(sizeof(*bs), GFP_KERNEL);

	if (!bs)

		return NULL;



	if (bioset_init(bs, pool_size, front_pad, flags)) {

		kfree(bs);

		return NULL;

	}



	return bs;

}

EXPORT_SYMBOL(bioset_create);



#ifdef CONFIG_BLK_CGROUP

include/linux/bio.h

+2 −0
Original line number Diff line number Diff line
@@ -406,6 +406,8 @@ static inline struct bio *bio_next_split(struct bio *bio, int sectors, 
	return bio_split(bio, sectors, gfp, bs);

}



extern int bioset_init(struct bio_set *, unsigned int, unsigned int, int flags);

extern void bioset_exit(struct bio_set *);

extern struct bio_set *bioset_create(unsigned int, unsigned int, int flags);

enum {

	BIOSET_NEED_BVECS = BIT(0),