X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=fs%2Fbio.c;h=402cb84a92a1dbd538dc4eead68cd474bea3389b;hb=96ec2e0a719fd61791dd2b0dd01325c5d20e1233;hp=d59ddbf79626cd0ca546a15bac0196544445fafd;hpb=992c5ddaf1b8b85d2252339c4c89adf7469c09ca;p=safe%2Fjmp%2Flinux-2.6 diff --git a/fs/bio.c b/fs/bio.c index d59ddbf..402cb84 100644 --- a/fs/bio.c +++ b/fs/bio.c @@ -25,58 +25,150 @@ #include #include #include -#include #include /* for struct sg_iovec */ -#define BIO_POOL_SIZE 2 - -static struct kmem_cache *bio_slab __read_mostly; - -#define BIOVEC_NR_POOLS 6 +#include /* - * 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++; + } + + 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); -static inline struct bio_vec *bvec_alloc_bs(gfp_t gfp_mask, int nr, unsigned long *idx, struct bio_set *bs) + 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; @@ -84,97 +176,161 @@ static inline struct bio_vec *bvec_alloc_bs(gfp_t gfp_mask, int nr, unsigned lon * 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, bs); - mempool_free(bio, bio_set->bio_pool); -} + /* + * If we have front padding, adjust the bio pointer before freeing + */ + p = bio; + if (bs->front_pad) + p -= bs->front_pad; -/* - * default destructor for a bio allocated with bio_alloc_bioset() - */ -static void bio_fs_destructor(struct bio *bio) -{ - bio_free(bio, fs_bio_set); + mempool_free(p, bs->bio_pool); } +EXPORT_SYMBOL(bio_free); 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); } +EXPORT_SYMBOL(bio_init); /** * 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); + unsigned long idx = BIO_POOL_NONE; + struct bio_vec *bvl = NULL; + struct bio *bio; + void *p; - if (likely(bio)) { - struct bio_vec *bvl = NULL; + p = mempool_alloc(bs->bio_pool, gfp_mask); + if (unlikely(!p)) + return NULL; + bio = p + bs->front_pad; - bio_init(bio); - if (likely(nr_iovecs)) { - unsigned long idx = 0; /* shut up gcc */ + bio_init(bio); - 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 (unlikely(!nr_iovecs)) + goto out_set; + + 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: +out_set: + bio->bi_flags |= idx << BIO_POOL_OFFSET; + bio->bi_max_vecs = nr_iovecs; + bio->bi_io_vec = bvl; return bio; + +err_free: + mempool_free(p, bs->bio_pool); + return NULL; +} +EXPORT_SYMBOL(bio_alloc_bioset); + +static void bio_fs_destructor(struct bio *bio) +{ + bio_free(bio, fs_bio_set); } +/** + * bio_alloc - allocate a new bio, memory pool backed + * @gfp_mask: allocation mask to use + * @nr_iovecs: number of iovecs + * + * Allocate a new bio with @nr_iovecs bvecs. If @gfp_mask + * contains __GFP_WAIT, the allocation is guaranteed to succeed. + * + * RETURNS: + * Pointer to new bio on success, NULL on failure. + */ struct bio *bio_alloc(gfp_t gfp_mask, int nr_iovecs) { struct bio *bio = bio_alloc_bioset(gfp_mask, nr_iovecs, fs_bio_set); @@ -184,6 +340,51 @@ struct bio *bio_alloc(gfp_t gfp_mask, int nr_iovecs) return bio; } +EXPORT_SYMBOL(bio_alloc); + +static void bio_kmalloc_destructor(struct bio *bio) +{ + if (bio_integrity(bio)) + bio_integrity_free(bio, fs_bio_set); + kfree(bio); +} + +/** + * bio_alloc - allocate a bio for I/O + * @gfp_mask: the GFP_ mask given to the slab allocator + * @nr_iovecs: number of iovecs to pre-allocate + * + * Description: + * bio_alloc will allocate a bio and associated bio_vec array that can hold + * at least @nr_iovecs entries. Allocations will be done from the + * fs_bio_set. Also see @bio_alloc_bioset. + * + * If %__GFP_WAIT is set, then bio_alloc will always be able to allocate + * a bio. This is due to the mempool guarantees. To make this work, callers + * must never allocate more than 1 bio at a time from this pool. Callers + * that need to allocate more than 1 bio must always submit the previously + * allocated bio for IO before attempting to allocate a new one. Failure to + * do so can cause livelocks under memory pressure. + * + **/ +struct bio *bio_kmalloc(gfp_t gfp_mask, int nr_iovecs) +{ + struct bio *bio; + + bio = kmalloc(sizeof(struct bio) + nr_iovecs * sizeof(struct bio_vec), + gfp_mask); + if (unlikely(!bio)) + return NULL; + + bio_init(bio); + 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; +} +EXPORT_SYMBOL(bio_kmalloc); void zero_fill_bio(struct bio *bio) { @@ -220,6 +421,7 @@ void bio_put(struct bio *bio) bio->bi_destructor(bio); } } +EXPORT_SYMBOL(bio_put); inline int bio_phys_segments(struct request_queue *q, struct bio *bio) { @@ -228,14 +430,7 @@ inline int bio_phys_segments(struct request_queue *q, struct bio *bio) 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; -} +EXPORT_SYMBOL(bio_phys_segments); /** * __bio_clone - clone a bio @@ -248,11 +443,13 @@ inline int bio_hw_segments(struct request_queue *q, struct bio *bio) */ void __bio_clone(struct bio *bio, struct bio *bio_src) { - struct request_queue *q = bdev_get_queue(bio_src->bi_bdev); - memcpy(bio->bi_io_vec, bio_src->bi_io_vec, bio_src->bi_max_vecs * sizeof(struct bio_vec)); + /* + * most users will be overriding ->bi_bdev with a new target, + * so we don't set nor calculate new physical/hw segment counts here + */ bio->bi_sector = bio_src->bi_sector; bio->bi_bdev = bio_src->bi_bdev; bio->bi_flags |= 1 << BIO_CLONED; @@ -260,9 +457,8 @@ void __bio_clone(struct bio *bio, struct bio *bio_src) bio->bi_vcnt = bio_src->bi_vcnt; bio->bi_size = bio_src->bi_size; bio->bi_idx = bio_src->bi_idx; - bio_phys_segments(q, bio); - bio_hw_segments(q, bio); } +EXPORT_SYMBOL(__bio_clone); /** * bio_clone - clone a bio @@ -275,13 +471,26 @@ struct bio *bio_clone(struct bio *bio, gfp_t gfp_mask) { 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, fs_bio_set); + + if (ret < 0) { + bio_put(b); + return NULL; + } } return b; } +EXPORT_SYMBOL(bio_clone); /** * bio_get_nr_vecs - return approx number of vecs @@ -297,14 +506,15 @@ int bio_get_nr_vecs(struct block_device *bdev) struct request_queue *q = bdev_get_queue(bdev); int nr_pages; - nr_pages = ((q->max_sectors << 9) + PAGE_SIZE - 1) >> PAGE_SHIFT; - if (nr_pages > q->max_phys_segments) - nr_pages = q->max_phys_segments; - if (nr_pages > q->max_hw_segments) - nr_pages = q->max_hw_segments; + nr_pages = ((queue_max_sectors(q) << 9) + PAGE_SIZE - 1) >> PAGE_SHIFT; + if (nr_pages > queue_max_phys_segments(q)) + nr_pages = queue_max_phys_segments(q); + if (nr_pages > queue_max_hw_segments(q)) + nr_pages = queue_max_hw_segments(q); return nr_pages; } +EXPORT_SYMBOL(bio_get_nr_vecs); static int __bio_add_page(struct request_queue *q, struct bio *bio, struct page *page, unsigned int len, unsigned int offset, @@ -333,10 +543,19 @@ static int __bio_add_page(struct request_queue *q, struct bio *bio, struct page 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; @@ -351,9 +570,8 @@ static int __bio_add_page(struct request_queue *q, struct bio *bio, struct page * make this too complex. */ - while (bio->bi_phys_segments >= q->max_phys_segments - || bio->bi_hw_segments >= q->max_hw_segments - || BIOVEC_VIRT_OVERSIZE(bio->bi_size)) { + while (bio->bi_phys_segments >= queue_max_phys_segments(q) + || bio->bi_phys_segments >= queue_max_hw_segments(q)) { if (retried_segments) return 0; @@ -377,11 +595,18 @@ static int __bio_add_page(struct request_queue *q, struct bio *bio, struct page * 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; @@ -390,13 +615,11 @@ static int __bio_add_page(struct request_queue *q, struct bio *bio, struct page } /* 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; @@ -419,8 +642,10 @@ static int __bio_add_page(struct request_queue *q, struct bio *bio, struct page int bio_add_pc_page(struct request_queue *q, struct bio *bio, struct page *page, unsigned int len, unsigned int offset) { - return __bio_add_page(q, bio, page, len, offset, q->max_hw_sectors); + return __bio_add_page(q, bio, page, len, offset, + queue_max_hw_sectors(q)); } +EXPORT_SYMBOL(bio_add_pc_page); /** * bio_add_page - attempt to add page to bio @@ -439,41 +664,110 @@ int bio_add_page(struct bio *bio, struct page *page, unsigned int len, unsigned int offset) { struct request_queue *q = bdev_get_queue(bio->bi_bdev); - return __bio_add_page(q, bio, page, len, offset, q->max_sectors); + return __bio_add_page(q, bio, page, len, offset, queue_max_sectors(q)); } +EXPORT_SYMBOL(bio_add_page); 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 to_user, int from_user, int do_free_page) +{ + int ret = 0, i; + struct bio_vec *bvec; + int iov_idx = 0; + unsigned int iov_off = 0; + + __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 __user *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 (to_user) + ret = copy_to_user(iov_addr, bv_addr, + bytes); + + if (from_user) + ret = copy_from_user(bv_addr, iov_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 @@ -484,77 +778,109 @@ static struct bio_map_data *bio_alloc_map_data(int nr_segs) 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, bio_data_dir(bio) == READ, + 0, bmd->is_our_pages); bio_free_map_data(bmd); bio_put(bio); return ret; } +EXPORT_SYMBOL(bio_uncopy_user); /** - * 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; - bmd = bio_alloc_map_data(end - start); + 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; + + nr_pages += end - start; + len += iov[i].iov_len; + } + + if (offset) + nr_pages++; + + 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_kmalloc(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) @@ -563,27 +889,19 @@ struct bio *bio_copy_user(struct request_queue *q, unsigned long uaddr, /* * 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)) || + (map_data && map_data->from_user)) { + ret = __bio_copy_iov(bio, bio->bi_io_vec, iov, iov_count, 0, 1, 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: @@ -591,10 +909,36 @@ 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); +} +EXPORT_SYMBOL(bio_copy_user); + 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; @@ -620,12 +964,12 @@ static struct bio *__bio_map_user_iov(struct request_queue *q, if (!nr_pages) return ERR_PTR(-EINVAL); - bio = bio_alloc(GFP_KERNEL, nr_pages); + bio = bio_kmalloc(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; @@ -637,12 +981,8 @@ static struct bio *__bio_map_user_iov(struct request_queue *q, 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; @@ -708,20 +1048,23 @@ static struct bio *__bio_map_user_iov(struct request_queue *q, * @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); } +EXPORT_SYMBOL(bio_map_user); /** * bio_map_user_iov - map user sg_iovec table into bio @@ -730,18 +1073,19 @@ struct bio *bio_map_user(struct request_queue *q, struct block_device *bdev, * @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; @@ -788,13 +1132,13 @@ void bio_unmap_user(struct bio *bio) __bio_unmap_user(bio); bio_put(bio); } +EXPORT_SYMBOL(bio_unmap_user); static void bio_map_kern_endio(struct bio *bio, int err) { bio_put(bio); } - static struct bio *__bio_map_kern(struct request_queue *q, void *data, unsigned int len, gfp_t gfp_mask) { @@ -805,7 +1149,7 @@ static struct bio *__bio_map_kern(struct request_queue *q, void *data, int offset, i; struct bio *bio; - bio = bio_alloc(gfp_mask, nr_pages); + bio = bio_kmalloc(gfp_mask, nr_pages); if (!bio) return ERR_PTR(-ENOMEM); @@ -860,6 +1204,69 @@ struct bio *bio_map_kern(struct request_queue *q, void *data, unsigned int len, bio_put(bio); return ERR_PTR(-EINVAL); } +EXPORT_SYMBOL(bio_map_kern); + +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) + 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; +} +EXPORT_SYMBOL(bio_copy_kern); /* * bio_set_pages_dirty() and bio_check_pages_dirty() are support functions @@ -903,7 +1310,7 @@ void bio_set_pages_dirty(struct bio *bio) } } -void bio_release_pages(struct bio *bio) +static void bio_release_pages(struct bio *bio) { struct bio_vec *bvec = bio->bi_io_vec; int i; @@ -1010,6 +1417,7 @@ void bio_endio(struct bio *bio, int error) if (bio->bi_end_io) bio->bi_end_io(bio, error); } +EXPORT_SYMBOL(bio_endio); void bio_pair_release(struct bio_pair *bp) { @@ -1020,6 +1428,7 @@ void bio_pair_release(struct bio_pair *bp) mempool_free(bp, bp->bio2.bi_private); } } +EXPORT_SYMBOL(bio_pair_release); static void bio_pair_end_1(struct bio *bi, int err) { @@ -1042,17 +1451,16 @@ static void bio_pair_end_2(struct bio *bi, int err) } /* - * split a bio - only worry about a bio with a single page - * in it's iovec + * split a bio - only worry about a bio with a single page in its 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); @@ -1081,11 +1489,52 @@ struct bio_pair *bio_split(struct bio *bi, mempool_t *pool, int first_sectors) 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; } +EXPORT_SYMBOL(bio_split); +/** + * 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; + struct bio_vec *bv; + sector_t sectors; + int i; + + sector_sz = queue_logical_block_size(bio->bi_bdev->bd_disk->queue); + 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. @@ -1093,30 +1542,18 @@ struct bio_pair *bio_split(struct bio *bi, mempool_t *pool, int first_sectors) */ 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) @@ -1124,29 +1561,59 @@ void bioset_free(struct bio_set *bs) if (bs->bio_pool) mempool_destroy(bs->bio_pool); + bioset_integrity_free(bs); biovec_free_pools(bs); + bio_put_slab(bs); kfree(bs); } +EXPORT_SYMBOL(bioset_free); -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 (bioset_integrity_create(bs, pool_size)) + goto bad; + + if (!biovec_create_pools(bs, pool_size)) return bs; bad: bioset_free(bs); return NULL; } +EXPORT_SYMBOL(bioset_create); static void __init biovec_init_slabs(void) { @@ -1156,6 +1623,13 @@ static void __init biovec_init_slabs(void) 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); @@ -1164,11 +1638,16 @@ static void __init biovec_init_slabs(void) 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"); + bio_integrity_init(); 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"); @@ -1179,27 +1658,4 @@ static int __init init_bio(void) return 0; } - subsys_initcall(init_bio); - -EXPORT_SYMBOL(bio_alloc); -EXPORT_SYMBOL(bio_put); -EXPORT_SYMBOL(bio_free); -EXPORT_SYMBOL(bio_endio); -EXPORT_SYMBOL(bio_init); -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_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); -EXPORT_SYMBOL(bioset_free); -EXPORT_SYMBOL(bio_alloc_bioset);