#include <linux/mempool.h>
#include <linux/workqueue.h>
#include <linux/blktrace_api.h>
+#include <trace/block.h>
#include <scsi/sg.h> /* for struct sg_iovec */
-#define BIO_POOL_SIZE 2
-
-static struct kmem_cache *bio_slab __read_mostly;
-
-#define BIOVEC_NR_POOLS 6
+DEFINE_TRACE(block_split);
/*
- * a small number of entries is fine, not going to be performance critical.
- * basically we just need to survive
+ * Test patch to inline a certain number of bi_io_vec's inside the bio
+ * itself, to shrink a bio data allocation from two mempool calls to one
*/
-#define BIO_SPLIT_ENTRIES 2
-mempool_t *bio_split_pool __read_mostly;
+#define BIO_INLINE_VECS 4
-struct biovec_slab {
- int nr_vecs;
- char *name;
- struct kmem_cache *slab;
-};
+static mempool_t *bio_split_pool __read_mostly;
/*
* if you change this list, also change bvec_alloc or things will
* break badly! cannot be bigger than what you can fit into an
* unsigned short
*/
-
#define BV(x) { .nr_vecs = x, .name = "biovec-"__stringify(x) }
-static struct biovec_slab bvec_slabs[BIOVEC_NR_POOLS] __read_mostly = {
+struct biovec_slab bvec_slabs[BIOVEC_NR_POOLS] __read_mostly = {
BV(1), BV(4), BV(16), BV(64), BV(128), BV(BIO_MAX_PAGES),
};
#undef BV
/*
- * 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[].
+ * fs_bio_set is the bio_set containing bio and iovec memory pools used by
+ * IO code that does not need private memory pools.
*/
-struct bio_set {
- mempool_t *bio_pool;
- mempool_t *bvec_pools[BIOVEC_NR_POOLS];
-};
+struct bio_set *fs_bio_set;
/*
- * fs_bio_set is the bio_set containing bio and iovec memory pools used by
- * IO code that does not need private memory pools.
+ * Our slab pool management
*/
-static struct bio_set *fs_bio_set;
+struct bio_slab {
+ struct kmem_cache *slab;
+ unsigned int slab_ref;
+ unsigned int slab_size;
+ char name[8];
+};
+static DEFINE_MUTEX(bio_slab_lock);
+static struct bio_slab *bio_slabs;
+static unsigned int bio_slab_nr, bio_slab_max;
+
+static struct kmem_cache *bio_find_or_create_slab(unsigned int extra_size)
+{
+ unsigned int sz = sizeof(struct bio) + extra_size;
+ struct kmem_cache *slab = NULL;
+ struct bio_slab *bslab;
+ unsigned int i, entry = -1;
+
+ mutex_lock(&bio_slab_lock);
+
+ i = 0;
+ while (i < bio_slab_nr) {
+ struct bio_slab *bslab = &bio_slabs[i];
+
+ if (!bslab->slab && entry == -1)
+ entry = i;
+ else if (bslab->slab_size == sz) {
+ slab = bslab->slab;
+ bslab->slab_ref++;
+ break;
+ }
+ i++;
+ }
-static inline struct bio_vec *bvec_alloc_bs(gfp_t gfp_mask, int nr, unsigned long *idx, struct bio_set *bs)
+ if (slab)
+ goto out_unlock;
+
+ if (bio_slab_nr == bio_slab_max && entry == -1) {
+ bio_slab_max <<= 1;
+ bio_slabs = krealloc(bio_slabs,
+ bio_slab_max * sizeof(struct bio_slab),
+ GFP_KERNEL);
+ if (!bio_slabs)
+ goto out_unlock;
+ }
+ if (entry == -1)
+ entry = bio_slab_nr++;
+
+ bslab = &bio_slabs[entry];
+
+ snprintf(bslab->name, sizeof(bslab->name), "bio-%d", entry);
+ slab = kmem_cache_create(bslab->name, sz, 0, SLAB_HWCACHE_ALIGN, NULL);
+ if (!slab)
+ goto out_unlock;
+
+ printk("bio: create slab <%s> at %d\n", bslab->name, entry);
+ bslab->slab = slab;
+ bslab->slab_ref = 1;
+ bslab->slab_size = sz;
+out_unlock:
+ mutex_unlock(&bio_slab_lock);
+ return slab;
+}
+
+static void bio_put_slab(struct bio_set *bs)
+{
+ struct bio_slab *bslab = NULL;
+ unsigned int i;
+
+ mutex_lock(&bio_slab_lock);
+
+ for (i = 0; i < bio_slab_nr; i++) {
+ if (bs->bio_slab == bio_slabs[i].slab) {
+ bslab = &bio_slabs[i];
+ break;
+ }
+ }
+
+ if (WARN(!bslab, KERN_ERR "bio: unable to find slab!\n"))
+ goto out;
+
+ WARN_ON(!bslab->slab_ref);
+
+ if (--bslab->slab_ref)
+ goto out;
+
+ kmem_cache_destroy(bslab->slab);
+ bslab->slab = NULL;
+
+out:
+ mutex_unlock(&bio_slab_lock);
+}
+
+unsigned int bvec_nr_vecs(unsigned short idx)
+{
+ return bvec_slabs[idx].nr_vecs;
+}
+
+void bvec_free_bs(struct bio_set *bs, struct bio_vec *bv, unsigned int idx)
+{
+ BIO_BUG_ON(idx >= BIOVEC_NR_POOLS);
+
+ if (idx == BIOVEC_MAX_IDX)
+ mempool_free(bv, bs->bvec_pool);
+ else {
+ struct biovec_slab *bvs = bvec_slabs + idx;
+
+ kmem_cache_free(bvs->slab, bv);
+ }
+}
+
+struct bio_vec *bvec_alloc_bs(gfp_t gfp_mask, int nr, unsigned long *idx,
+ struct bio_set *bs)
{
struct bio_vec *bvl;
/*
+ * If 'bs' is given, lookup the pool and do the mempool alloc.
+ * If not, this is a bio_kmalloc() allocation and just do a
+ * kzalloc() for the exact number of vecs right away.
+ */
+ if (!bs)
+ bvl = kmalloc(nr * sizeof(struct bio_vec), gfp_mask);
+
+ /*
* see comment near bvec_array define!
*/
switch (nr) {
- case 1 : *idx = 0; break;
- case 2 ... 4: *idx = 1; break;
- case 5 ... 16: *idx = 2; break;
- case 17 ... 64: *idx = 3; break;
- case 65 ... 128: *idx = 4; break;
- case 129 ... BIO_MAX_PAGES: *idx = 5; break;
- default:
- return NULL;
+ case 1:
+ *idx = 0;
+ break;
+ case 2 ... 4:
+ *idx = 1;
+ break;
+ case 5 ... 16:
+ *idx = 2;
+ break;
+ case 17 ... 64:
+ *idx = 3;
+ break;
+ case 65 ... 128:
+ *idx = 4;
+ break;
+ case 129 ... BIO_MAX_PAGES:
+ *idx = 5;
+ break;
+ default:
+ return NULL;
}
+
/*
- * idx now points to the pool we want to allocate from
+ * idx now points to the pool we want to allocate from. only the
+ * 1-vec entry pool is mempool backed.
*/
+ if (*idx == BIOVEC_MAX_IDX) {
+fallback:
+ bvl = mempool_alloc(bs->bvec_pool, gfp_mask);
+ } else {
+ struct biovec_slab *bvs = bvec_slabs + *idx;
+ gfp_t __gfp_mask = gfp_mask & ~(__GFP_WAIT | __GFP_IO);
- bvl = mempool_alloc(bs->bvec_pools[*idx], gfp_mask);
- if (bvl) {
- struct biovec_slab *bp = bvec_slabs + *idx;
+ /*
+ * Make this allocation restricted and don't dump info on
+ * allocation failures, since we'll fallback to the mempool
+ * in case of failure.
+ */
+ __gfp_mask |= __GFP_NOMEMALLOC | __GFP_NORETRY | __GFP_NOWARN;
- memset(bvl, 0, bp->nr_vecs * sizeof(struct bio_vec));
+ /*
+ * Try a slab allocation. If this fails and __GFP_WAIT
+ * is set, retry with the 1-entry mempool
+ */
+ bvl = kmem_cache_alloc(bvs->slab, __gfp_mask);
+ if (unlikely(!bvl && (gfp_mask & __GFP_WAIT))) {
+ *idx = BIOVEC_MAX_IDX;
+ goto fallback;
+ }
}
return bvl;
}
-void bio_free(struct bio *bio, struct bio_set *bio_set)
+void bio_free(struct bio *bio, struct bio_set *bs)
{
- if (bio->bi_io_vec) {
- const int pool_idx = BIO_POOL_IDX(bio);
+ void *p;
- BIO_BUG_ON(pool_idx >= BIOVEC_NR_POOLS);
+ if (bio_has_allocated_vec(bio))
+ bvec_free_bs(bs, bio->bi_io_vec, BIO_POOL_IDX(bio));
- mempool_free(bio->bi_io_vec, bio_set->bvec_pools[pool_idx]);
- }
+ 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)
+ p -= bs->front_pad;
- mempool_free(bio, bio_set->bio_pool);
+ mempool_free(p, bs->bio_pool);
}
/*
bio_free(bio, fs_bio_set);
}
+static void bio_kmalloc_destructor(struct bio *bio)
+{
+ if (bio_has_allocated_vec(bio))
+ kfree(bio->bi_io_vec);
+ kfree(bio);
+}
+
void bio_init(struct bio *bio)
{
memset(bio, 0, sizeof(*bio));
bio->bi_flags = 1 << BIO_UPTODATE;
+ bio->bi_comp_cpu = -1;
atomic_set(&bio->bi_cnt, 1);
}
* 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
+ * @bs: the bio_set to allocate from. If %NULL, just use kmalloc
*
* Description:
- * bio_alloc_bioset will first try it's on mempool to satisfy the allocation.
+ * bio_alloc_bioset will first try its own 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.
+ * for a &struct bio to become free. If a %NULL @bs is passed in, we will
+ * fall back to just using @kmalloc to allocate the required memory.
*
- * allocate bio and iovecs from the memory pools specified by the
- * bio_set structure.
+ * Note that the caller must set ->bi_destructor on succesful return
+ * of a bio, to do the appropriate freeing of the bio once the reference
+ * count drops to zero.
**/
struct bio *bio_alloc_bioset(gfp_t gfp_mask, int nr_iovecs, struct bio_set *bs)
{
- struct bio *bio = mempool_alloc(bs->bio_pool, gfp_mask);
+ struct bio_vec *bvl = NULL;
+ struct bio *bio = NULL;
+ unsigned long idx = 0;
+ void *p = NULL;
+
+ if (bs) {
+ p = mempool_alloc(bs->bio_pool, gfp_mask);
+ if (!p)
+ goto err;
+ bio = p + bs->front_pad;
+ } else {
+ bio = kmalloc(sizeof(*bio), gfp_mask);
+ if (!bio)
+ goto err;
+ }
- if (likely(bio)) {
- struct bio_vec *bvl = NULL;
+ bio_init(bio);
- bio_init(bio);
- if (likely(nr_iovecs)) {
- unsigned long idx = 0; /* shut up gcc */
+ if (unlikely(!nr_iovecs))
+ goto out_set;
- bvl = bvec_alloc_bs(gfp_mask, nr_iovecs, &idx, bs);
- if (unlikely(!bvl)) {
- mempool_free(bio, bs->bio_pool);
- bio = NULL;
- goto out;
- }
- bio->bi_flags |= idx << BIO_POOL_OFFSET;
- bio->bi_max_vecs = bvec_slabs[idx].nr_vecs;
- }
- bio->bi_io_vec = bvl;
+ if (nr_iovecs <= BIO_INLINE_VECS) {
+ bvl = bio->bi_inline_vecs;
+ nr_iovecs = BIO_INLINE_VECS;
+ } else {
+ bvl = bvec_alloc_bs(gfp_mask, nr_iovecs, &idx, bs);
+ if (unlikely(!bvl))
+ goto err_free;
+
+ nr_iovecs = bvec_nr_vecs(idx);
}
-out:
+ bio->bi_flags |= idx << BIO_POOL_OFFSET;
+ bio->bi_max_vecs = nr_iovecs;
+out_set:
+ bio->bi_io_vec = bvl;
+
return bio;
+
+err_free:
+ if (bs)
+ mempool_free(p, bs->bio_pool);
+ else
+ kfree(bio);
+err:
+ return NULL;
}
struct bio *bio_alloc(gfp_t gfp_mask, int nr_iovecs)
return bio;
}
+/*
+ * Like bio_alloc(), but doesn't use a mempool backing. This means that
+ * it CAN fail, but while bio_alloc() can only be used for allocations
+ * that have a short (finite) life span, bio_kmalloc() should be used
+ * for more permanent bio allocations (like allocating some bio's for
+ * initalization or setup purposes).
+ */
+struct bio *bio_kmalloc(gfp_t gfp_mask, int nr_iovecs)
+{
+ struct bio *bio = bio_alloc_bioset(gfp_mask, nr_iovecs, NULL);
+
+ if (bio)
+ bio->bi_destructor = bio_kmalloc_destructor;
+
+ return bio;
+}
+
void zero_fill_bio(struct bio *bio)
{
unsigned long flags;
return bio->bi_phys_segments;
}
-inline int bio_hw_segments(struct request_queue *q, struct bio *bio)
-{
- if (unlikely(!bio_flagged(bio, BIO_SEG_VALID)))
- blk_recount_segments(q, bio);
-
- return bio->bi_hw_segments;
-}
-
/**
* __bio_clone - clone a bio
* @bio: destination bio
{
struct bio *b = bio_alloc_bioset(gfp_mask, bio->bi_max_vecs, fs_bio_set);
- if (b) {
- b->bi_destructor = bio_fs_destructor;
- __bio_clone(b, bio);
+ if (!b)
+ return NULL;
+
+ b->bi_destructor = bio_fs_destructor;
+ __bio_clone(b, bio);
+
+ if (bio_integrity(bio)) {
+ int ret;
+
+ ret = bio_integrity_clone(b, bio, gfp_mask);
+
+ if (ret < 0) {
+ bio_put(b);
+ return NULL;
+ }
}
return b;
if (page == prev->bv_page &&
offset == prev->bv_offset + prev->bv_len) {
prev->bv_len += len;
- if (q->merge_bvec_fn &&
- q->merge_bvec_fn(q, bio, prev) < len) {
- prev->bv_len -= len;
- return 0;
+
+ if (q->merge_bvec_fn) {
+ struct bvec_merge_data bvm = {
+ .bi_bdev = bio->bi_bdev,
+ .bi_sector = bio->bi_sector,
+ .bi_size = bio->bi_size,
+ .bi_rw = bio->bi_rw,
+ };
+
+ if (q->merge_bvec_fn(q, &bvm, prev) < len) {
+ prev->bv_len -= len;
+ return 0;
+ }
}
goto done;
*/
while (bio->bi_phys_segments >= q->max_phys_segments
- || bio->bi_hw_segments >= q->max_hw_segments
- || BIOVEC_VIRT_OVERSIZE(bio->bi_size)) {
+ || bio->bi_phys_segments >= q->max_hw_segments) {
if (retried_segments)
return 0;
* queue to get further control
*/
if (q->merge_bvec_fn) {
+ struct bvec_merge_data bvm = {
+ .bi_bdev = bio->bi_bdev,
+ .bi_sector = bio->bi_sector,
+ .bi_size = bio->bi_size,
+ .bi_rw = bio->bi_rw,
+ };
+
/*
* merge_bvec_fn() returns number of bytes it can accept
* at this offset
*/
- if (q->merge_bvec_fn(q, bio, bvec) < len) {
+ if (q->merge_bvec_fn(q, &bvm, bvec) < len) {
bvec->bv_page = NULL;
bvec->bv_len = 0;
bvec->bv_offset = 0;
}
/* If we may be able to merge these biovecs, force a recount */
- if (bio->bi_vcnt && (BIOVEC_PHYS_MERGEABLE(bvec-1, bvec) ||
- BIOVEC_VIRT_MERGEABLE(bvec-1, bvec)))
+ if (bio->bi_vcnt && (BIOVEC_PHYS_MERGEABLE(bvec-1, bvec)))
bio->bi_flags &= ~(1 << BIO_SEG_VALID);
bio->bi_vcnt++;
bio->bi_phys_segments++;
- bio->bi_hw_segments++;
done:
bio->bi_size += len;
return len;
struct bio_map_data {
struct bio_vec *iovecs;
- void __user *userptr;
+ struct sg_iovec *sgvecs;
+ int nr_sgvecs;
+ int is_our_pages;
};
-static void bio_set_map_data(struct bio_map_data *bmd, struct bio *bio)
+static void bio_set_map_data(struct bio_map_data *bmd, struct bio *bio,
+ struct sg_iovec *iov, int iov_count,
+ int is_our_pages)
{
memcpy(bmd->iovecs, bio->bi_io_vec, sizeof(struct bio_vec) * bio->bi_vcnt);
+ memcpy(bmd->sgvecs, iov, sizeof(struct sg_iovec) * iov_count);
+ bmd->nr_sgvecs = iov_count;
+ bmd->is_our_pages = is_our_pages;
bio->bi_private = bmd;
}
static void bio_free_map_data(struct bio_map_data *bmd)
{
kfree(bmd->iovecs);
+ kfree(bmd->sgvecs);
kfree(bmd);
}
-static struct bio_map_data *bio_alloc_map_data(int nr_segs)
+static struct bio_map_data *bio_alloc_map_data(int nr_segs, int iov_count,
+ gfp_t gfp_mask)
{
- struct bio_map_data *bmd = kmalloc(sizeof(*bmd), GFP_KERNEL);
+ struct bio_map_data *bmd = kmalloc(sizeof(*bmd), gfp_mask);
if (!bmd)
return NULL;
- bmd->iovecs = kmalloc(sizeof(struct bio_vec) * nr_segs, GFP_KERNEL);
- if (bmd->iovecs)
+ bmd->iovecs = kmalloc(sizeof(struct bio_vec) * nr_segs, gfp_mask);
+ if (!bmd->iovecs) {
+ kfree(bmd);
+ return NULL;
+ }
+
+ bmd->sgvecs = kmalloc(sizeof(struct sg_iovec) * iov_count, gfp_mask);
+ if (bmd->sgvecs)
return bmd;
+ kfree(bmd->iovecs);
kfree(bmd);
return NULL;
}
+static int __bio_copy_iov(struct bio *bio, struct bio_vec *iovecs,
+ struct sg_iovec *iov, int iov_count, int uncopy,
+ int do_free_page)
+{
+ int ret = 0, i;
+ struct bio_vec *bvec;
+ int iov_idx = 0;
+ unsigned int iov_off = 0;
+ int read = bio_data_dir(bio) == READ;
+
+ __bio_for_each_segment(bvec, bio, i, 0) {
+ char *bv_addr = page_address(bvec->bv_page);
+ unsigned int bv_len = iovecs[i].bv_len;
+
+ while (bv_len && iov_idx < iov_count) {
+ unsigned int bytes;
+ char *iov_addr;
+
+ bytes = min_t(unsigned int,
+ iov[iov_idx].iov_len - iov_off, bv_len);
+ iov_addr = iov[iov_idx].iov_base + iov_off;
+
+ if (!ret) {
+ if (!read && !uncopy)
+ ret = copy_from_user(bv_addr, iov_addr,
+ bytes);
+ if (read && uncopy)
+ ret = copy_to_user(iov_addr, bv_addr,
+ bytes);
+
+ if (ret)
+ ret = -EFAULT;
+ }
+
+ bv_len -= bytes;
+ bv_addr += bytes;
+ iov_addr += bytes;
+ iov_off += bytes;
+
+ if (iov[iov_idx].iov_len == iov_off) {
+ iov_idx++;
+ iov_off = 0;
+ }
+ }
+
+ if (do_free_page)
+ __free_page(bvec->bv_page);
+ }
+
+ return ret;
+}
+
/**
* bio_uncopy_user - finish previously mapped bio
* @bio: bio being terminated
int bio_uncopy_user(struct bio *bio)
{
struct bio_map_data *bmd = bio->bi_private;
- const int read = bio_data_dir(bio) == READ;
- struct bio_vec *bvec;
- int i, ret = 0;
-
- __bio_for_each_segment(bvec, bio, i, 0) {
- char *addr = page_address(bvec->bv_page);
- unsigned int len = bmd->iovecs[i].bv_len;
+ int ret = 0;
- if (read && !ret && copy_to_user(bmd->userptr, addr, len))
- ret = -EFAULT;
-
- __free_page(bvec->bv_page);
- bmd->userptr += len;
- }
+ if (!bio_flagged(bio, BIO_NULL_MAPPED))
+ ret = __bio_copy_iov(bio, bmd->iovecs, bmd->sgvecs,
+ bmd->nr_sgvecs, 1, bmd->is_our_pages);
bio_free_map_data(bmd);
bio_put(bio);
return ret;
}
/**
- * bio_copy_user - copy user data to bio
+ * bio_copy_user_iov - copy user data to bio
* @q: destination block queue
- * @uaddr: start of user address
- * @len: length in bytes
+ * @map_data: pointer to the rq_map_data holding pages (if necessary)
+ * @iov: the iovec.
+ * @iov_count: number of elements in the iovec
* @write_to_vm: bool indicating writing to pages or not
+ * @gfp_mask: memory allocation flags
*
* Prepares and returns a bio for indirect user io, bouncing data
* to/from kernel pages as necessary. Must be paired with
* call bio_uncopy_user() on io completion.
*/
-struct bio *bio_copy_user(struct request_queue *q, unsigned long uaddr,
- unsigned int len, int write_to_vm)
+struct bio *bio_copy_user_iov(struct request_queue *q,
+ struct rq_map_data *map_data,
+ struct sg_iovec *iov, int iov_count,
+ int write_to_vm, gfp_t gfp_mask)
{
- unsigned long end = (uaddr + len + PAGE_SIZE - 1) >> PAGE_SHIFT;
- unsigned long start = uaddr >> PAGE_SHIFT;
struct bio_map_data *bmd;
struct bio_vec *bvec;
struct page *page;
struct bio *bio;
int i, ret;
+ int nr_pages = 0;
+ unsigned int len = 0;
+ unsigned int offset = map_data ? map_data->offset & ~PAGE_MASK : 0;
+
+ for (i = 0; i < iov_count; i++) {
+ unsigned long uaddr;
+ unsigned long end;
+ unsigned long start;
+
+ uaddr = (unsigned long)iov[i].iov_base;
+ end = (uaddr + iov[i].iov_len + PAGE_SIZE - 1) >> PAGE_SHIFT;
+ start = uaddr >> PAGE_SHIFT;
- bmd = bio_alloc_map_data(end - start);
+ nr_pages += end - start;
+ len += iov[i].iov_len;
+ }
+
+ bmd = bio_alloc_map_data(nr_pages, iov_count, gfp_mask);
if (!bmd)
return ERR_PTR(-ENOMEM);
- bmd->userptr = (void __user *) uaddr;
-
ret = -ENOMEM;
- bio = bio_alloc(GFP_KERNEL, end - start);
+ bio = bio_alloc(gfp_mask, nr_pages);
if (!bio)
goto out_bmd;
bio->bi_rw |= (!write_to_vm << BIO_RW);
ret = 0;
+
+ if (map_data) {
+ nr_pages = 1 << map_data->page_order;
+ i = map_data->offset / PAGE_SIZE;
+ }
while (len) {
unsigned int bytes = PAGE_SIZE;
+ bytes -= offset;
+
if (bytes > len)
bytes = len;
- page = alloc_page(q->bounce_gfp | GFP_KERNEL);
- if (!page) {
- ret = -ENOMEM;
- break;
+ if (map_data) {
+ if (i == map_data->nr_entries * nr_pages) {
+ ret = -ENOMEM;
+ break;
+ }
+
+ page = map_data->pages[i / nr_pages];
+ page += (i % nr_pages);
+
+ i++;
+ } else {
+ page = alloc_page(q->bounce_gfp | gfp_mask);
+ if (!page) {
+ ret = -ENOMEM;
+ break;
+ }
}
- if (bio_add_pc_page(q, bio, page, bytes, 0) < bytes)
+ if (bio_add_pc_page(q, bio, page, bytes, offset) < bytes)
break;
len -= bytes;
+ offset = 0;
}
if (ret)
/*
* success
*/
- if (!write_to_vm) {
- char __user *p = (char __user *) uaddr;
-
- /*
- * for a write, copy in data to kernel pages
- */
- ret = -EFAULT;
- bio_for_each_segment(bvec, bio, i) {
- char *addr = page_address(bvec->bv_page);
-
- if (copy_from_user(addr, p, bvec->bv_len))
- goto cleanup;
- p += bvec->bv_len;
- }
+ if (!write_to_vm && (!map_data || !map_data->null_mapped)) {
+ ret = __bio_copy_iov(bio, bio->bi_io_vec, iov, iov_count, 0, 0);
+ if (ret)
+ goto cleanup;
}
- bio_set_map_data(bmd, bio);
+ bio_set_map_data(bmd, bio, iov, iov_count, map_data ? 0 : 1);
return bio;
cleanup:
- bio_for_each_segment(bvec, bio, i)
- __free_page(bvec->bv_page);
+ if (!map_data)
+ bio_for_each_segment(bvec, bio, i)
+ __free_page(bvec->bv_page);
bio_put(bio);
out_bmd:
return ERR_PTR(ret);
}
+/**
+ * bio_copy_user - copy user data to bio
+ * @q: destination block queue
+ * @map_data: pointer to the rq_map_data holding pages (if necessary)
+ * @uaddr: start of user address
+ * @len: length in bytes
+ * @write_to_vm: bool indicating writing to pages or not
+ * @gfp_mask: memory allocation flags
+ *
+ * Prepares and returns a bio for indirect user io, bouncing data
+ * to/from kernel pages as necessary. Must be paired with
+ * call bio_uncopy_user() on io completion.
+ */
+struct bio *bio_copy_user(struct request_queue *q, struct rq_map_data *map_data,
+ unsigned long uaddr, unsigned int len,
+ int write_to_vm, gfp_t gfp_mask)
+{
+ struct sg_iovec iov;
+
+ iov.iov_base = (void __user *)uaddr;
+ iov.iov_len = len;
+
+ return bio_copy_user_iov(q, map_data, &iov, 1, write_to_vm, gfp_mask);
+}
+
static struct bio *__bio_map_user_iov(struct request_queue *q,
struct block_device *bdev,
struct sg_iovec *iov, int iov_count,
- int write_to_vm)
+ int write_to_vm, gfp_t gfp_mask)
{
int i, j;
int nr_pages = 0;
if (!nr_pages)
return ERR_PTR(-EINVAL);
- bio = bio_alloc(GFP_KERNEL, nr_pages);
+ bio = bio_alloc(gfp_mask, nr_pages);
if (!bio)
return ERR_PTR(-ENOMEM);
ret = -ENOMEM;
- pages = kcalloc(nr_pages, sizeof(struct page *), GFP_KERNEL);
+ pages = kcalloc(nr_pages, sizeof(struct page *), gfp_mask);
if (!pages)
goto out;
const int local_nr_pages = end - start;
const int page_limit = cur_page + local_nr_pages;
- down_read(¤t->mm->mmap_sem);
- ret = get_user_pages(current, current->mm, uaddr,
- local_nr_pages,
- write_to_vm, 0, &pages[cur_page], NULL);
- up_read(¤t->mm->mmap_sem);
-
+ ret = get_user_pages_fast(uaddr, local_nr_pages,
+ write_to_vm, &pages[cur_page]);
if (ret < local_nr_pages) {
ret = -EFAULT;
goto out_unmap;
* @uaddr: start of user address
* @len: length in bytes
* @write_to_vm: bool indicating writing to pages or not
+ * @gfp_mask: memory allocation flags
*
* Map the user space address into a bio suitable for io to a block
* device. Returns an error pointer in case of error.
*/
struct bio *bio_map_user(struct request_queue *q, struct block_device *bdev,
- unsigned long uaddr, unsigned int len, int write_to_vm)
+ unsigned long uaddr, unsigned int len, int write_to_vm,
+ gfp_t gfp_mask)
{
struct sg_iovec iov;
iov.iov_base = (void __user *)uaddr;
iov.iov_len = len;
- return bio_map_user_iov(q, bdev, &iov, 1, write_to_vm);
+ return bio_map_user_iov(q, bdev, &iov, 1, write_to_vm, gfp_mask);
}
/**
* @iov: the iovec.
* @iov_count: number of elements in the iovec
* @write_to_vm: bool indicating writing to pages or not
+ * @gfp_mask: memory allocation flags
*
* Map the user space address into a bio suitable for io to a block
* device. Returns an error pointer in case of error.
*/
struct bio *bio_map_user_iov(struct request_queue *q, struct block_device *bdev,
struct sg_iovec *iov, int iov_count,
- int write_to_vm)
+ int write_to_vm, gfp_t gfp_mask)
{
struct bio *bio;
- bio = __bio_map_user_iov(q, bdev, iov, iov_count, write_to_vm);
-
+ bio = __bio_map_user_iov(q, bdev, iov, iov_count, write_to_vm,
+ gfp_mask);
if (IS_ERR(bio))
return bio;
return ERR_PTR(-EINVAL);
}
+static void bio_copy_kern_endio(struct bio *bio, int err)
+{
+ struct bio_vec *bvec;
+ const int read = bio_data_dir(bio) == READ;
+ struct bio_map_data *bmd = bio->bi_private;
+ int i;
+ char *p = bmd->sgvecs[0].iov_base;
+
+ __bio_for_each_segment(bvec, bio, i, 0) {
+ char *addr = page_address(bvec->bv_page);
+ int len = bmd->iovecs[i].bv_len;
+
+ if (read && !err)
+ memcpy(p, addr, len);
+
+ __free_page(bvec->bv_page);
+ p += len;
+ }
+
+ bio_free_map_data(bmd);
+ bio_put(bio);
+}
+
+/**
+ * bio_copy_kern - copy kernel address into bio
+ * @q: the struct request_queue for the bio
+ * @data: pointer to buffer to copy
+ * @len: length in bytes
+ * @gfp_mask: allocation flags for bio and page allocation
+ * @reading: data direction is READ
+ *
+ * copy the kernel address into a bio suitable for io to a block
+ * device. Returns an error pointer in case of error.
+ */
+struct bio *bio_copy_kern(struct request_queue *q, void *data, unsigned int len,
+ gfp_t gfp_mask, int reading)
+{
+ struct bio *bio;
+ struct bio_vec *bvec;
+ int i;
+
+ bio = bio_copy_user(q, NULL, (unsigned long)data, len, 1, gfp_mask);
+ if (IS_ERR(bio))
+ return bio;
+
+ if (!reading) {
+ void *p = data;
+
+ bio_for_each_segment(bvec, bio, i) {
+ char *addr = page_address(bvec->bv_page);
+
+ memcpy(addr, p, bvec->bv_len);
+ p += bvec->bv_len;
+ }
+ }
+
+ bio->bi_end_io = bio_copy_kern_endio;
+
+ return bio;
+}
+
/*
* bio_set_pages_dirty() and bio_check_pages_dirty() are support functions
* for performing direct-IO in BIOs.
* split a bio - only worry about a bio with a single page
* in it's iovec
*/
-struct bio_pair *bio_split(struct bio *bi, mempool_t *pool, int first_sectors)
+struct bio_pair *bio_split(struct bio *bi, int first_sectors)
{
- struct bio_pair *bp = mempool_alloc(pool, GFP_NOIO);
+ struct bio_pair *bp = mempool_alloc(bio_split_pool, GFP_NOIO);
if (!bp)
return bp;
- blk_add_trace_pdu_int(bdev_get_queue(bi->bi_bdev), BLK_TA_SPLIT, bi,
+ trace_block_split(bdev_get_queue(bi->bi_bdev), bi,
bi->bi_sector + first_sectors);
BUG_ON(bi->bi_vcnt != 1);
bp->bio2.bi_end_io = bio_pair_end_2;
bp->bio1.bi_private = bi;
- bp->bio2.bi_private = pool;
+ bp->bio2.bi_private = bio_split_pool;
+
+ if (bio_integrity(bi))
+ bio_integrity_split(bi, bp, first_sectors);
return bp;
}
+/**
+ * bio_sector_offset - Find hardware sector offset in bio
+ * @bio: bio to inspect
+ * @index: bio_vec index
+ * @offset: offset in bv_page
+ *
+ * Return the number of hardware sectors between beginning of bio
+ * and an end point indicated by a bio_vec index and an offset
+ * within that vector's page.
+ */
+sector_t bio_sector_offset(struct bio *bio, unsigned short index,
+ unsigned int offset)
+{
+ unsigned int sector_sz = queue_hardsect_size(bio->bi_bdev->bd_disk->queue);
+ struct bio_vec *bv;
+ sector_t sectors;
+ int i;
+
+ sectors = 0;
+
+ if (index >= bio->bi_idx)
+ index = bio->bi_vcnt - 1;
+
+ __bio_for_each_segment(bv, bio, i, 0) {
+ if (i == index) {
+ if (offset > bv->bv_offset)
+ sectors += (offset - bv->bv_offset) / sector_sz;
+ break;
+ }
+
+ sectors += bv->bv_len / sector_sz;
+ }
+
+ return sectors;
+}
+EXPORT_SYMBOL(bio_sector_offset);
/*
* create memory pools for biovec's in a bio_set.
*/
static int biovec_create_pools(struct bio_set *bs, int pool_entries)
{
- int i;
+ struct biovec_slab *bp = bvec_slabs + BIOVEC_MAX_IDX;
- for (i = 0; i < BIOVEC_NR_POOLS; i++) {
- struct biovec_slab *bp = bvec_slabs + i;
- mempool_t **bvp = bs->bvec_pools + i;
+ bs->bvec_pool = mempool_create_slab_pool(pool_entries, bp->slab);
+ if (!bs->bvec_pool)
+ return -ENOMEM;
- *bvp = mempool_create_slab_pool(pool_entries, 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);
- }
-
+ mempool_destroy(bs->bvec_pool);
}
void bioset_free(struct bio_set *bs)
mempool_destroy(bs->bio_pool);
biovec_free_pools(bs);
+ bio_put_slab(bs);
kfree(bs);
}
-struct bio_set *bioset_create(int bio_pool_size, int bvec_pool_size)
+/**
+ * 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)
{
- struct bio_set *bs = kzalloc(sizeof(*bs), GFP_KERNEL);
+ 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->bio_pool = mempool_create_slab_pool(bio_pool_size, bio_slab);
+ bs->front_pad = front_pad;
+
+ bs->bio_slab = bio_find_or_create_slab(front_pad + back_pad);
+ if (!bs->bio_slab) {
+ kfree(bs);
+ return NULL;
+ }
+
+ bs->bio_pool = mempool_create_slab_pool(pool_size, bs->bio_slab);
if (!bs->bio_pool)
goto bad;
- if (!biovec_create_pools(bs, bvec_pool_size))
+ if (!biovec_create_pools(bs, pool_size))
return bs;
bad:
int size;
struct biovec_slab *bvs = bvec_slabs + i;
+#ifndef CONFIG_BLK_DEV_INTEGRITY
+ if (bvs->nr_vecs <= BIO_INLINE_VECS) {
+ bvs->slab = NULL;
+ continue;
+ }
+#endif
+
size = bvs->nr_vecs * sizeof(struct bio_vec);
bvs->slab = kmem_cache_create(bvs->name, size, 0,
SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
static int __init init_bio(void)
{
- bio_slab = KMEM_CACHE(bio, SLAB_HWCACHE_ALIGN|SLAB_PANIC);
+ bio_slab_max = 2;
+ bio_slab_nr = 0;
+ bio_slabs = kzalloc(bio_slab_max * sizeof(struct bio_slab), GFP_KERNEL);
+ if (!bio_slabs)
+ panic("bio: can't allocate bios\n");
biovec_init_slabs();
- fs_bio_set = bioset_create(BIO_POOL_SIZE, 2);
+ fs_bio_set = bioset_create(BIO_POOL_SIZE, 0);
if (!fs_bio_set)
panic("bio: can't allocate bios\n");
subsys_initcall(init_bio);
EXPORT_SYMBOL(bio_alloc);
+EXPORT_SYMBOL(bio_kmalloc);
EXPORT_SYMBOL(bio_put);
EXPORT_SYMBOL(bio_free);
EXPORT_SYMBOL(bio_endio);
EXPORT_SYMBOL(__bio_clone);
EXPORT_SYMBOL(bio_clone);
EXPORT_SYMBOL(bio_phys_segments);
-EXPORT_SYMBOL(bio_hw_segments);
EXPORT_SYMBOL(bio_add_page);
EXPORT_SYMBOL(bio_add_pc_page);
EXPORT_SYMBOL(bio_get_nr_vecs);
+EXPORT_SYMBOL(bio_map_user);
+EXPORT_SYMBOL(bio_unmap_user);
EXPORT_SYMBOL(bio_map_kern);
+EXPORT_SYMBOL(bio_copy_kern);
EXPORT_SYMBOL(bio_pair_release);
EXPORT_SYMBOL(bio_split);
-EXPORT_SYMBOL(bio_split_pool);
EXPORT_SYMBOL(bio_copy_user);
EXPORT_SYMBOL(bio_uncopy_user);
EXPORT_SYMBOL(bioset_create);