diff options
Diffstat (limited to 'fs/bio.c')
| -rw-r--r-- | fs/bio.c | 116 |
1 files changed, 63 insertions, 53 deletions
@@ -78,7 +78,7 @@ static struct kmem_cache *bio_find_or_create_slab(unsigned int extra_size) i = 0; while (i < bio_slab_nr) { - struct bio_slab *bslab = &bio_slabs[i]; + bslab = &bio_slabs[i]; if (!bslab->slab && entry == -1) entry = i; @@ -249,6 +249,7 @@ void bio_free(struct bio *bio, struct bio_set *bs) mempool_free(p, bs->bio_pool); } +EXPORT_SYMBOL(bio_free); void bio_init(struct bio *bio) { @@ -257,20 +258,20 @@ void bio_init(struct bio *bio) 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. If %NULL, just use kmalloc + * @bs: the bio_set to allocate from. * * Description: - * bio_alloc_bioset will first try its own mempool to satisfy the allocation. + * bio_alloc_bioset will 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. If a %NULL @bs is passed in, we will - * fall back to just using @kmalloc to allocate the required memory. + * for a &struct bio to become free. * - * Note that the caller must set ->bi_destructor on succesful return + * Note that the caller must set ->bi_destructor on successful return * of a bio, to do the appropriate freeing of the bio once the reference * count drops to zero. **/ @@ -311,6 +312,7 @@ err_free: mempool_free(p, bs->bio_pool); return NULL; } +EXPORT_SYMBOL(bio_alloc_bioset); static void bio_fs_destructor(struct bio *bio) { @@ -322,8 +324,16 @@ static void bio_fs_destructor(struct bio *bio) * @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. + * 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 and @bio_kmalloc. + * + * 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. * * RETURNS: * Pointer to new bio on success, NULL on failure. @@ -337,6 +347,7 @@ 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) { @@ -346,21 +357,13 @@ static void bio_kmalloc_destructor(struct bio *bio) } /** - * bio_alloc - allocate a bio for I/O + * bio_kmalloc - allocate a bio for I/O using kmalloc() * @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. + * Allocate a new bio with @nr_iovecs bvecs. If @gfp_mask contains + * %__GFP_WAIT, the allocation is guaranteed to succeed. * **/ struct bio *bio_kmalloc(gfp_t gfp_mask, int nr_iovecs) @@ -380,6 +383,7 @@ struct bio *bio_kmalloc(gfp_t gfp_mask, int nr_iovecs) return bio; } +EXPORT_SYMBOL(bio_kmalloc); void zero_fill_bio(struct bio *bio) { @@ -402,7 +406,7 @@ EXPORT_SYMBOL(zero_fill_bio); * * Description: * Put a reference to a &struct bio, either one you have gotten with - * bio_alloc or bio_get. The last put of a bio will free it. + * bio_alloc, bio_get or bio_clone. The last put of a bio will free it. **/ void bio_put(struct bio *bio) { @@ -416,6 +420,7 @@ 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) { @@ -424,6 +429,7 @@ inline int bio_phys_segments(struct request_queue *q, struct bio *bio) return bio->bi_phys_segments; } +EXPORT_SYMBOL(bio_phys_segments); /** * __bio_clone - clone a bio @@ -451,6 +457,7 @@ void __bio_clone(struct bio *bio, struct bio *bio_src) bio->bi_size = bio_src->bi_size; bio->bi_idx = bio_src->bi_idx; } +EXPORT_SYMBOL(__bio_clone); /** * bio_clone - clone a bio @@ -482,6 +489,7 @@ struct bio *bio_clone(struct bio *bio, gfp_t gfp_mask) return b; } +EXPORT_SYMBOL(bio_clone); /** * bio_get_nr_vecs - return approx number of vecs @@ -498,13 +506,12 @@ int bio_get_nr_vecs(struct block_device *bdev) int nr_pages; 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); + if (nr_pages > queue_max_segments(q)) + nr_pages = queue_max_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, @@ -532,13 +539,18 @@ 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) { + unsigned int prev_bv_len = prev->bv_len; prev->bv_len += len; if (q->merge_bvec_fn) { struct bvec_merge_data bvm = { + /* prev_bvec is already charged in + bi_size, discharge it in order to + simulate merging updated prev_bvec + as new bvec. */ .bi_bdev = bio->bi_bdev, .bi_sector = bio->bi_sector, - .bi_size = bio->bi_size, + .bi_size = bio->bi_size - prev_bv_len, .bi_rw = bio->bi_rw, }; @@ -560,8 +572,7 @@ static int __bio_add_page(struct request_queue *q, struct bio *bio, struct page * make this too complex. */ - while (bio->bi_phys_segments >= queue_max_phys_segments(q) - || bio->bi_phys_segments >= queue_max_hw_segments(q)) { + while (bio->bi_phys_segments >= queue_max_segments(q)) { if (retried_segments) return 0; @@ -635,6 +646,7 @@ int bio_add_pc_page(struct request_queue *q, struct bio *bio, struct page *page, 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 @@ -655,6 +667,7 @@ int bio_add_page(struct bio *bio, struct page *page, unsigned int len, struct request_queue *q = bdev_get_queue(bio->bi_bdev); 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; @@ -776,6 +789,7 @@ int bio_uncopy_user(struct bio *bio) bio_put(bio); return ret; } +EXPORT_SYMBOL(bio_uncopy_user); /** * bio_copy_user_iov - copy user data to bio @@ -920,6 +934,7 @@ struct bio *bio_copy_user(struct request_queue *q, struct rq_map_data *map_data, 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, @@ -1050,6 +1065,7 @@ struct bio *bio_map_user(struct request_queue *q, struct block_device *bdev, 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 @@ -1117,13 +1133,13 @@ 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) { @@ -1189,6 +1205,7 @@ 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) { @@ -1250,6 +1267,7 @@ struct bio *bio_copy_kern(struct request_queue *q, void *data, unsigned int len, return bio; } +EXPORT_SYMBOL(bio_copy_kern); /* * bio_set_pages_dirty() and bio_check_pages_dirty() are support functions @@ -1376,6 +1394,18 @@ void bio_check_pages_dirty(struct bio *bio) } } +#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE +void bio_flush_dcache_pages(struct bio *bi) +{ + int i; + struct bio_vec *bvec; + + bio_for_each_segment(bvec, bi, i) + flush_dcache_page(bvec->bv_page); +} +EXPORT_SYMBOL(bio_flush_dcache_pages); +#endif + /** * bio_endio - end I/O on a bio * @bio: bio @@ -1400,6 +1430,7 @@ 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) { @@ -1410,6 +1441,7 @@ 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) { @@ -1477,6 +1509,7 @@ struct bio_pair *bio_split(struct bio *bi, int first_sectors) return bp; } +EXPORT_SYMBOL(bio_split); /** * bio_sector_offset - Find hardware sector offset in bio @@ -1547,6 +1580,7 @@ void bioset_free(struct bio_set *bs) kfree(bs); } +EXPORT_SYMBOL(bioset_free); /** * bioset_create - Create a bio_set @@ -1592,6 +1626,7 @@ bad: bioset_free(bs); return NULL; } +EXPORT_SYMBOL(bioset_create); static void __init biovec_init_slabs(void) { @@ -1636,29 +1671,4 @@ static int __init init_bio(void) return 0; } - 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_init); -EXPORT_SYMBOL(__bio_clone); -EXPORT_SYMBOL(bio_clone); -EXPORT_SYMBOL(bio_phys_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_copy_user); -EXPORT_SYMBOL(bio_uncopy_user); -EXPORT_SYMBOL(bioset_create); -EXPORT_SYMBOL(bioset_free); -EXPORT_SYMBOL(bio_alloc_bioset); |