blk: replace bioset_create_nobvec() with a flags arg to bioset_create()

"flags" arguments are often seen as good API design as they allow
easy extensibility.
bioset_create_nobvec() is implemented internally as a variation in
flags passed to __bioset_create().

To support future extension, make the internal structure part of the
API.
i.e. add a 'flags' argument to bioset_create() and discard
bioset_create_nobvec().

Note that the bio_split allocations in drivers/md/raid* do not need
the bvec mempool - they should have used bioset_create_nobvec().

Suggested-by: Christoph Hellwig <hch@infradead.org>
Reviewed-by: Christoph Hellwig <hch@infradead.org>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/block/bio.c b/block/bio.c
index 0e36ca5..84b313b 100644 (file)
--- a/block/bio.c
+++ b/block/bio.c
@@ -1921,9 +1921,26 @@ void bioset_free(struct bio_set *bs)
 }
 EXPORT_SYMBOL(bioset_free);
 
-static struct bio_set *__bioset_create(unsigned int pool_size,
-                                      unsigned int front_pad,
-                                      bool create_bvec_pool)
+/**
+ * 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 only %BIOSET_NEED_BVECS
+ *
+ * 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().
+ *
+ */
+struct bio_set *bioset_create(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;
@@ -1948,7 +1965,7 @@ static struct bio_set *__bioset_create(unsigned int pool_size,
        if (!bs->bio_pool)
                goto bad;
 
-       if (create_bvec_pool) {
+       if (flags & BIOSET_NEED_BVECS) {
                bs->bvec_pool = biovec_create_pool(pool_size);
                if (!bs->bvec_pool)
                        goto bad;
@@ -1963,41 +1980,8 @@ bad:
        bioset_free(bs);
        return NULL;
 }
-
-/**
- * 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
- *
- * 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.
- */
-struct bio_set *bioset_create(unsigned int pool_size, unsigned int front_pad)
-{
-       return __bioset_create(pool_size, front_pad, true);
-}
 EXPORT_SYMBOL(bioset_create);
 
-/**
- * bioset_create_nobvec  - Create a bio_set without bio_vec mempool
- * @pool_size: Number of bio to cache in the mempool
- * @front_pad: Number of bytes to allocate in front of the returned bio
- *
- * Description:
- *    Same functionality as bioset_create() except that mempool is not
- *    created for bio_vecs. Saving some memory for bio_clone_fast() users.
- */
-struct bio_set *bioset_create_nobvec(unsigned int pool_size, unsigned int front_pad)
-{
-       return __bioset_create(pool_size, front_pad, false);
-}
-EXPORT_SYMBOL(bioset_create_nobvec);
-
 #ifdef CONFIG_BLK_CGROUP
 
 /**
@@ -2112,7 +2096,7 @@ static int __init init_bio(void)
        bio_integrity_init();
        biovec_init_slabs();
 
-       fs_bio_set = bioset_create(BIO_POOL_SIZE, 0);
+       fs_bio_set = bioset_create(BIO_POOL_SIZE, 0, BIOSET_NEED_BVECS);
        if (!fs_bio_set)
                panic("bio: can't allocate bios\n");
 

diff --git a/block/blk-core.c b/block/blk-core.c
index 31b5ece..62cf925 100644 (file)
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -790,7 +790,7 @@ struct request_queue *blk_alloc_queue_node(gfp_t gfp_mask, int node_id)
        if (q->id < 0)
                goto fail_q;
 
-       q->bio_split = bioset_create(BIO_POOL_SIZE, 0);
+       q->bio_split = bioset_create(BIO_POOL_SIZE, 0, BIOSET_NEED_BVECS);
        if (!q->bio_split)
                goto fail_id;
 

diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c
index 84455c3..b395fe3 100644 (file)
--- a/drivers/block/drbd/drbd_main.c
+++ b/drivers/block/drbd/drbd_main.c
@@ -2165,7 +2165,7 @@ static int drbd_create_mempools(void)
                goto Enomem;
 
        /* mempools */
-       drbd_md_io_bio_set = bioset_create(DRBD_MIN_POOL_PAGES, 0);
+       drbd_md_io_bio_set = bioset_create(DRBD_MIN_POOL_PAGES, 0, BIOSET_NEED_BVECS);
        if (drbd_md_io_bio_set == NULL)
                goto Enomem;
 

diff --git a/drivers/md/bcache/super.c b/drivers/md/bcache/super.c
index fbc4f54..abd6e82 100644 (file)
--- a/drivers/md/bcache/super.c
+++ b/drivers/md/bcache/super.c
@@ -782,7 +782,7 @@ static int bcache_device_init(struct bcache_device *d, unsigned block_size,
 
        minor *= BCACHE_MINORS;
 
-       if (!(d->bio_split = bioset_create(4, offsetof(struct bbio, bio))) ||
+       if (!(d->bio_split = bioset_create(4, offsetof(struct bbio, bio), BIOSET_NEED_BVECS)) ||
            !(d->disk = alloc_disk(BCACHE_MINORS))) {
                ida_simple_remove(&bcache_minor, minor);
                return -ENOMEM;
@@ -1516,7 +1516,7 @@ struct cache_set *bch_cache_set_alloc(struct cache_sb *sb)
                                sizeof(struct bbio) + sizeof(struct bio_vec) *
                                bucket_pages(c))) ||
            !(c->fill_iter = mempool_create_kmalloc_pool(1, iter_size)) ||
-           !(c->bio_split = bioset_create(4, offsetof(struct bbio, bio))) ||
+           !(c->bio_split = bioset_create(4, offsetof(struct bbio, bio), BIOSET_NEED_BVECS)) ||
            !(c->uuids = alloc_bucket_pages(GFP_KERNEL, c)) ||
            !(c->moving_gc_wq = alloc_workqueue("bcache_gc",
                                                WQ_MEM_RECLAIM, 0)) ||

diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index 586cef0..237ff8e 100644 (file)
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -2677,7 +2677,7 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
                goto bad;
        }
 
-       cc->bs = bioset_create(MIN_IOS, 0);
+       cc->bs = bioset_create(MIN_IOS, 0, BIOSET_NEED_BVECS);
        if (!cc->bs) {
                ti->error = "Cannot allocate crypt bioset";
                goto bad;

diff --git a/drivers/md/dm-io.c b/drivers/md/dm-io.c
index c8f8f30..5c41210 100644 (file)
--- a/drivers/md/dm-io.c
+++ b/drivers/md/dm-io.c
@@ -58,7 +58,7 @@ struct dm_io_client *dm_io_client_create(void)
        if (!client->pool)
                goto bad;
 
-       client->bios = bioset_create(min_ios, 0);
+       client->bios = bioset_create(min_ios, 0, BIOSET_NEED_BVECS);
        if (!client->bios)
                goto bad;
 

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index c4b74f7..3394a31 100644 (file)
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -2660,7 +2660,7 @@ struct dm_md_mempools *dm_alloc_md_mempools(struct mapped_device *md, enum dm_qu
                BUG();
        }
 
-       pools->bs = bioset_create_nobvec(pool_size, front_pad);
+       pools->bs = bioset_create(pool_size, front_pad, 0);
        if (!pools->bs)
                goto out;
 

diff --git a/drivers/md/md.c b/drivers/md/md.c
index d43df11..07fe780 100644 (file)
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -5428,7 +5428,7 @@ int md_run(struct mddev *mddev)
        }
 
        if (mddev->bio_set == NULL) {
-               mddev->bio_set = bioset_create(BIO_POOL_SIZE, 0);
+               mddev->bio_set = bioset_create(BIO_POOL_SIZE, 0, BIOSET_NEED_BVECS);
                if (!mddev->bio_set)
                        return -ENOMEM;
        }

diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index a1a3cf0..98ca2c1 100644 (file)
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -2955,7 +2955,7 @@ static struct r1conf *setup_conf(struct mddev *mddev)
        if (!conf->r1bio_pool)
                goto abort;
 
-       conf->bio_split = bioset_create(BIO_POOL_SIZE, 0);
+       conf->bio_split = bioset_create(BIO_POOL_SIZE, 0, 0);
        if (!conf->bio_split)
                goto abort;
 

diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index 3178273..57a250f 100644 (file)
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -3552,7 +3552,7 @@ static struct r10conf *setup_conf(struct mddev *mddev)
        if (!conf->r10bio_pool)
                goto out;
 
-       conf->bio_split = bioset_create(BIO_POOL_SIZE, 0);
+       conf->bio_split = bioset_create(BIO_POOL_SIZE, 0, 0);
        if (!conf->bio_split)
                goto out;
 

diff --git a/drivers/md/raid5-cache.c b/drivers/md/raid5-cache.c
index 3746c9c..bfa1e90 100644 (file)
--- a/drivers/md/raid5-cache.c
+++ b/drivers/md/raid5-cache.c
@@ -3063,7 +3063,7 @@ int r5l_init_log(struct r5conf *conf, struct md_rdev *rdev)
        if (!log->io_pool)
                goto io_pool;
 
-       log->bs = bioset_create(R5L_POOL_SIZE, 0);
+       log->bs = bioset_create(R5L_POOL_SIZE, 0, BIOSET_NEED_BVECS);
        if (!log->bs)
                goto io_bs;
 

diff --git a/drivers/md/raid5-ppl.c b/drivers/md/raid5-ppl.c
index e709ada..77cce35 100644 (file)
--- a/drivers/md/raid5-ppl.c
+++ b/drivers/md/raid5-ppl.c
@@ -1150,7 +1150,7 @@ int ppl_init_log(struct r5conf *conf)
                goto err;
        }
 
-       ppl_conf->bs = bioset_create(conf->raid_disks, 0);
+       ppl_conf->bs = bioset_create(conf->raid_disks, 0, 0);
        if (!ppl_conf->bs) {
                ret = -ENOMEM;
                goto err;

diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 7171bfd..62c965b 100644 (file)
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -6943,7 +6943,7 @@ static struct r5conf *setup_conf(struct mddev *mddev)
                        goto abort;
        }
 
-       conf->bio_split = bioset_create(BIO_POOL_SIZE, 0);
+       conf->bio_split = bioset_create(BIO_POOL_SIZE, 0, 0);
        if (!conf->bio_split)
                goto abort;
        conf->mddev = mddev;

diff --git a/drivers/target/target_core_iblock.c b/drivers/target/target_core_iblock.c
index 7537362..c05d380 100644 (file)
--- a/drivers/target/target_core_iblock.c
+++ b/drivers/target/target_core_iblock.c
@@ -93,7 +93,7 @@ static int iblock_configure_device(struct se_device *dev)
                return -EINVAL;
        }
 
-       ib_dev->ibd_bio_set = bioset_create(IBLOCK_BIO_POOL_SIZE, 0);
+       ib_dev->ibd_bio_set = bioset_create(IBLOCK_BIO_POOL_SIZE, 0, BIOSET_NEED_BVECS);
        if (!ib_dev->ibd_bio_set) {
                pr_err("IBLOCK: Unable to create bioset\n");
                goto out;

diff --git a/fs/block_dev.c b/fs/block_dev.c
index bcd8e16..dd91c99 100644 (file)
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -439,7 +439,7 @@ blkdev_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
 
 static __init int blkdev_init(void)
 {
-       blkdev_dio_pool = bioset_create(4, offsetof(struct blkdev_dio, bio));
+       blkdev_dio_pool = bioset_create(4, offsetof(struct blkdev_dio, bio), BIOSET_NEED_BVECS);
        if (!blkdev_dio_pool)
                return -ENOMEM;
        return 0;

diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 8f66e55..19eedf2 100644 (file)
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -174,7 +174,8 @@ int __init extent_io_init(void)
                goto free_state_cache;
 
        btrfs_bioset = bioset_create(BIO_POOL_SIZE,
-                                    offsetof(struct btrfs_io_bio, bio));
+                                    offsetof(struct btrfs_io_bio, bio),
+                                    BIOSET_NEED_BVECS);
        if (!btrfs_bioset)
                goto free_buffer_cache;
 

diff --git a/fs/xfs/xfs_super.c b/fs/xfs/xfs_super.c
index 455a575..97df4db 100644 (file)
--- a/fs/xfs/xfs_super.c
+++ b/fs/xfs/xfs_super.c
@@ -1766,7 +1766,8 @@ STATIC int __init
 xfs_init_zones(void)
 {
        xfs_ioend_bioset = bioset_create(4 * MAX_BUF_PER_PAGE,
-                       offsetof(struct xfs_ioend, io_inline_bio));
+                       offsetof(struct xfs_ioend, io_inline_bio),
+                       BIOSET_NEED_BVECS);
        if (!xfs_ioend_bioset)
                goto out;
 

diff --git a/include/linux/bio.h b/include/linux/bio.h
index 9455aad..985dc64 100644 (file)
--- a/include/linux/bio.h
+++ b/include/linux/bio.h
@@ -373,8 +373,10 @@ static inline struct bio *bio_next_split(struct bio *bio, int sectors,
        return bio_split(bio, sectors, gfp, bs);
 }
 
-extern struct bio_set *bioset_create(unsigned int, unsigned int);
-extern struct bio_set *bioset_create_nobvec(unsigned int, unsigned int);
+extern struct bio_set *bioset_create(unsigned int, unsigned int, int flags);
+enum {
+       BIOSET_NEED_BVECS = BIT(0),
+};
 extern void bioset_free(struct bio_set *);
 extern mempool_t *biovec_create_pool(int pool_entries);