#define BIO_POOL_SIZE 256
-static mempool_t *bio_pool;
static kmem_cache_t *bio_slab;
#define BIOVEC_NR_POOLS 6
#define BIO_SPLIT_ENTRIES 8
mempool_t *bio_split_pool;
-struct biovec_pool {
+struct biovec_slab {
int nr_vecs;
char *name;
kmem_cache_t *slab;
- mempool_t *pool;
};
/*
*/
#define BV(x) { .nr_vecs = x, .name = "biovec-"__stringify(x) }
-static struct biovec_pool bvec_array[BIOVEC_NR_POOLS] = {
+static struct biovec_slab bvec_slabs[BIOVEC_NR_POOLS] = {
BV(1), BV(4), BV(16), BV(64), BV(128), BV(BIO_MAX_PAGES),
};
#undef BV
-static inline struct bio_vec *bvec_alloc(int gfp_mask, int nr, unsigned long *idx)
+/*
+ * bio_set is used to allow other portions of the IO system to
+ * allocate their own private memory pools for bio and iovec structures.
+ * These memory pools in turn all allocate from the bio_slab
+ * and the bvec_slabs[].
+ */
+struct bio_set {
+ mempool_t *bio_pool;
+ mempool_t *bvec_pools[BIOVEC_NR_POOLS];
+};
+
+/*
+ * fs_bio_set is the bio_set containing bio and iovec memory pools used by
+ * IO code that does not need private memory pools.
+ */
+static struct bio_set *fs_bio_set;
+
+static inline struct bio_vec *bvec_alloc_bs(unsigned int __nocast gfp_mask, int nr, unsigned long *idx, struct bio_set *bs)
{
- struct biovec_pool *bp;
struct bio_vec *bvl;
+ struct biovec_slab *bp;
/*
* see comment near bvec_array define!
/*
* idx now points to the pool we want to allocate from
*/
- bp = bvec_array + *idx;
- bvl = mempool_alloc(bp->pool, gfp_mask);
+ bp = bvec_slabs + *idx;
+ bvl = mempool_alloc(bs->bvec_pools[*idx], gfp_mask);
if (bvl)
memset(bvl, 0, bp->nr_vecs * sizeof(struct bio_vec));
+
return bvl;
}
/*
- * default destructor for a bio allocated with bio_alloc()
+ * default destructor for a bio allocated with bio_alloc_bioset()
*/
static void bio_destructor(struct bio *bio)
{
const int pool_idx = BIO_POOL_IDX(bio);
- struct biovec_pool *bp = bvec_array + pool_idx;
+ struct bio_set *bs = bio->bi_set;
BIO_BUG_ON(pool_idx >= BIOVEC_NR_POOLS);
- mempool_free(bio->bi_io_vec, bp->pool);
- mempool_free(bio, bio_pool);
+ mempool_free(bio->bi_io_vec, bs->bvec_pools[pool_idx]);
+ mempool_free(bio, bs->bio_pool);
}
inline void bio_init(struct bio *bio)
}
/**
- * bio_alloc - allocate a bio for I/O
+ * bio_alloc_bioset - allocate a bio for I/O
* @gfp_mask: the GFP_ mask given to the slab allocator
* @nr_iovecs: number of iovecs to pre-allocate
+ * @bs: the bio_set to allocate from
*
* Description:
- * bio_alloc will first try it's on mempool to satisfy the allocation.
+ * bio_alloc_bioset will first try it's on mempool to satisfy the allocation.
* If %__GFP_WAIT is set then we will block on the internal pool waiting
* for a &struct bio to become free.
+ *
+ * allocate bio and iovecs from the memory pools specified by the
+ * bio_set structure.
**/
-struct bio *bio_alloc(int gfp_mask, int nr_iovecs)
+struct bio *bio_alloc_bioset(unsigned int __nocast gfp_mask, int nr_iovecs, struct bio_set *bs)
{
- struct bio *bio = mempool_alloc(bio_pool, gfp_mask);
+ struct bio *bio = mempool_alloc(bs->bio_pool, gfp_mask);
if (likely(bio)) {
struct bio_vec *bvl = NULL;
if (likely(nr_iovecs)) {
unsigned long idx;
- bvl = bvec_alloc(gfp_mask, nr_iovecs, &idx);
+ bvl = bvec_alloc_bs(gfp_mask, nr_iovecs, &idx, bs);
if (unlikely(!bvl)) {
- mempool_free(bio, bio_pool);
+ mempool_free(bio, bs->bio_pool);
bio = NULL;
goto out;
}
bio->bi_flags |= idx << BIO_POOL_OFFSET;
- bio->bi_max_vecs = bvec_array[idx].nr_vecs;
+ bio->bi_max_vecs = bvec_slabs[idx].nr_vecs;
}
bio->bi_io_vec = bvl;
bio->bi_destructor = bio_destructor;
+ bio->bi_set = bs;
}
out:
return bio;
}
+struct bio *bio_alloc(unsigned int __nocast gfp_mask, int nr_iovecs)
+{
+ return bio_alloc_bioset(gfp_mask, nr_iovecs, fs_bio_set);
+}
+
+void zero_fill_bio(struct bio *bio)
+{
+ unsigned long flags;
+ struct bio_vec *bv;
+ int i;
+
+ bio_for_each_segment(bv, bio, i) {
+ char *data = bvec_kmap_irq(bv, &flags);
+ memset(data, 0, bv->bv_len);
+ flush_dcache_page(bv->bv_page);
+ bvec_kunmap_irq(data, &flags);
+ }
+}
+EXPORT_SYMBOL(zero_fill_bio);
+
/**
* bio_put - release a reference to a bio
* @bio: bio to release reference to
*
* Like __bio_clone, only also allocates the returned bio
*/
-struct bio *bio_clone(struct bio *bio, int gfp_mask)
+struct bio *bio_clone(struct bio *bio, unsigned int __nocast gfp_mask)
{
- struct bio *b = bio_alloc(gfp_mask, bio->bi_max_vecs);
+ struct bio *b = bio_alloc_bioset(gfp_mask, bio->bi_max_vecs, fs_bio_set);
if (b)
__bio_clone(b, bio);
/**
* bio_map_user - map user address into bio
+ * @q: the request_queue_t for the bio
* @bdev: destination block device
* @uaddr: start of user address
* @len: length in bytes
return bp;
}
-static void *bio_pair_alloc(int gfp_flags, void *data)
+static void *bio_pair_alloc(unsigned int __nocast gfp_flags, void *data)
{
return kmalloc(sizeof(struct bio_pair), gfp_flags);
}
kfree(bp);
}
-static void __init biovec_init_pools(void)
+
+/*
+ * create memory pools for biovec's in a bio_set.
+ * use the global biovec slabs created for general use.
+ */
+static int biovec_create_pools(struct bio_set *bs, int pool_entries, int scale)
{
- int i, size, megabytes, pool_entries = BIO_POOL_SIZE;
+ int i;
+
+ for (i = 0; i < BIOVEC_NR_POOLS; i++) {
+ struct biovec_slab *bp = bvec_slabs + i;
+ mempool_t **bvp = bs->bvec_pools + i;
+
+ if (i >= scale)
+ pool_entries >>= 1;
+
+ *bvp = mempool_create(pool_entries, mempool_alloc_slab,
+ mempool_free_slab, bp->slab);
+ if (!*bvp)
+ return -ENOMEM;
+ }
+ return 0;
+}
+
+static void biovec_free_pools(struct bio_set *bs)
+{
+ int i;
+
+ for (i = 0; i < BIOVEC_NR_POOLS; i++) {
+ mempool_t *bvp = bs->bvec_pools[i];
+
+ if (bvp)
+ mempool_destroy(bvp);
+ }
+
+}
+
+void bioset_free(struct bio_set *bs)
+{
+ if (bs->bio_pool)
+ mempool_destroy(bs->bio_pool);
+
+ biovec_free_pools(bs);
+
+ kfree(bs);
+}
+
+struct bio_set *bioset_create(int bio_pool_size, int bvec_pool_size, int scale)
+{
+ struct bio_set *bs = kmalloc(sizeof(*bs), GFP_KERNEL);
+
+ if (!bs)
+ return NULL;
+
+ memset(bs, 0, sizeof(*bs));
+ bs->bio_pool = mempool_create(bio_pool_size, mempool_alloc_slab,
+ mempool_free_slab, bio_slab);
+
+ if (!bs->bio_pool)
+ goto bad;
+
+ if (!biovec_create_pools(bs, bvec_pool_size, scale))
+ return bs;
+
+bad:
+ bioset_free(bs);
+ return NULL;
+}
+
+static void __init biovec_init_slabs(void)
+{
+ int i;
+
+ for (i = 0; i < BIOVEC_NR_POOLS; i++) {
+ int size;
+ struct biovec_slab *bvs = bvec_slabs + i;
+
+ size = bvs->nr_vecs * sizeof(struct bio_vec);
+ bvs->slab = kmem_cache_create(bvs->name, size, 0,
+ SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL, NULL);
+ }
+}
+
+static int __init init_bio(void)
+{
+ int megabytes, bvec_pool_entries;
int scale = BIOVEC_NR_POOLS;
+ bio_slab = kmem_cache_create("bio", sizeof(struct bio), 0,
+ SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL, NULL);
+
+ biovec_init_slabs();
+
megabytes = nr_free_pages() >> (20 - PAGE_SHIFT);
/*
/*
* scale number of entries
*/
- pool_entries = megabytes * 2;
- if (pool_entries > 256)
- pool_entries = 256;
-
- for (i = 0; i < BIOVEC_NR_POOLS; i++) {
- struct biovec_pool *bp = bvec_array + i;
-
- size = bp->nr_vecs * sizeof(struct bio_vec);
-
- bp->slab = kmem_cache_create(bp->name, size, 0,
- SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL, NULL);
-
- if (i >= scale)
- pool_entries >>= 1;
-
- bp->pool = mempool_create(pool_entries, mempool_alloc_slab,
- mempool_free_slab, bp->slab);
- if (!bp->pool)
- panic("biovec: can't init mempool\n");
- }
-}
-
-static int __init init_bio(void)
-{
- bio_slab = kmem_cache_create("bio", sizeof(struct bio), 0,
- SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL, NULL);
- bio_pool = mempool_create(BIO_POOL_SIZE, mempool_alloc_slab,
- mempool_free_slab, bio_slab);
- if (!bio_pool)
- panic("bio: can't create mempool\n");
+ bvec_pool_entries = megabytes * 2;
+ if (bvec_pool_entries > 256)
+ bvec_pool_entries = 256;
- biovec_init_pools();
+ fs_bio_set = bioset_create(BIO_POOL_SIZE, bvec_pool_entries, scale);
+ if (!fs_bio_set)
+ panic("bio: can't allocate bios\n");
bio_split_pool = mempool_create(BIO_SPLIT_ENTRIES,
bio_pair_alloc, bio_pair_free, NULL);
EXPORT_SYMBOL(bio_split_pool);
EXPORT_SYMBOL(bio_copy_user);
EXPORT_SYMBOL(bio_uncopy_user);
+EXPORT_SYMBOL(bioset_create);
+EXPORT_SYMBOL(bioset_free);
+EXPORT_SYMBOL(bio_alloc_bioset);
git://git.onelab.eu / linux-2.6.git / blobdiff