| /* SPDX-License-Identifier: GPL-2.0 */ |
| /* |
| * Copyright (C) 2001 Jens Axboe <axboe@suse.de> |
| */ |
| #ifndef __LINUX_BIO_H |
| #define __LINUX_BIO_H |
| |
| #include <linux/highmem.h> |
| #include <linux/mempool.h> |
| #include <linux/ioprio.h> |
| /* struct bio, bio_vec and BIO_* flags are defined in blk_types.h */ |
| #include <linux/blk_types.h> |
| #include <linux/uio.h> |
| |
| #define BIO_DEBUG |
| |
| #ifdef BIO_DEBUG |
| #define BIO_BUG_ON BUG_ON |
| #else |
| #define BIO_BUG_ON |
| #endif |
| |
| #define BIO_MAX_PAGES 256U |
| |
| static inline unsigned int bio_max_segs(unsigned int nr_segs) |
| { |
| return min(nr_segs, BIO_MAX_PAGES); |
| } |
| |
| #define bio_prio(bio) (bio)->bi_ioprio |
| #define bio_set_prio(bio, prio) ((bio)->bi_ioprio = prio) |
| |
| #define bio_iter_iovec(bio, iter) \ |
| bvec_iter_bvec((bio)->bi_io_vec, (iter)) |
| |
| #define bio_iter_page(bio, iter) \ |
| bvec_iter_page((bio)->bi_io_vec, (iter)) |
| #define bio_iter_len(bio, iter) \ |
| bvec_iter_len((bio)->bi_io_vec, (iter)) |
| #define bio_iter_offset(bio, iter) \ |
| bvec_iter_offset((bio)->bi_io_vec, (iter)) |
| |
| #define bio_page(bio) bio_iter_page((bio), (bio)->bi_iter) |
| #define bio_offset(bio) bio_iter_offset((bio), (bio)->bi_iter) |
| #define bio_iovec(bio) bio_iter_iovec((bio), (bio)->bi_iter) |
| |
| #define bio_multiple_segments(bio) \ |
| ((bio)->bi_iter.bi_size != bio_iovec(bio).bv_len) |
| |
| #define bvec_iter_sectors(iter) ((iter).bi_size >> 9) |
| #define bvec_iter_end_sector(iter) ((iter).bi_sector + bvec_iter_sectors((iter))) |
| |
| #define bio_sectors(bio) bvec_iter_sectors((bio)->bi_iter) |
| #define bio_end_sector(bio) bvec_iter_end_sector((bio)->bi_iter) |
| |
| /* |
| * Return the data direction, READ or WRITE. |
| */ |
| #define bio_data_dir(bio) \ |
| (op_is_write(bio_op(bio)) ? WRITE : READ) |
| |
| /* |
| * Check whether this bio carries any data or not. A NULL bio is allowed. |
| */ |
| static inline bool bio_has_data(struct bio *bio) |
| { |
| if (bio && |
| bio->bi_iter.bi_size && |
| bio_op(bio) != REQ_OP_DISCARD && |
| bio_op(bio) != REQ_OP_SECURE_ERASE && |
| bio_op(bio) != REQ_OP_WRITE_ZEROES) |
| return true; |
| |
| return false; |
| } |
| |
| static inline bool bio_no_advance_iter(const struct bio *bio) |
| { |
| return bio_op(bio) == REQ_OP_DISCARD || |
| bio_op(bio) == REQ_OP_SECURE_ERASE || |
| bio_op(bio) == REQ_OP_WRITE_SAME || |
| bio_op(bio) == REQ_OP_WRITE_ZEROES; |
| } |
| |
| static inline bool bio_mergeable(struct bio *bio) |
| { |
| if (bio->bi_opf & REQ_NOMERGE_FLAGS) |
| return false; |
| |
| return true; |
| } |
| |
| static inline unsigned int bio_cur_bytes(struct bio *bio) |
| { |
| if (bio_has_data(bio)) |
| return bio_iovec(bio).bv_len; |
| else /* dataless requests such as discard */ |
| return bio->bi_iter.bi_size; |
| } |
| |
| static inline void *bio_data(struct bio *bio) |
| { |
| if (bio_has_data(bio)) |
| return page_address(bio_page(bio)) + bio_offset(bio); |
| |
| return NULL; |
| } |
| |
| /** |
| * bio_full - check if the bio is full |
| * @bio: bio to check |
| * @len: length of one segment to be added |
| * |
| * Return true if @bio is full and one segment with @len bytes can't be |
| * added to the bio, otherwise return false |
| */ |
| static inline bool bio_full(struct bio *bio, unsigned len) |
| { |
| if (bio->bi_vcnt >= bio->bi_max_vecs) |
| return true; |
| |
| if (bio->bi_iter.bi_size > UINT_MAX - len) |
| return true; |
| |
| return false; |
| } |
| |
| static inline bool bio_next_segment(const struct bio *bio, |
| struct bvec_iter_all *iter) |
| { |
| if (iter->idx >= bio->bi_vcnt) |
| return false; |
| |
| bvec_advance(&bio->bi_io_vec[iter->idx], iter); |
| return true; |
| } |
| |
| /* |
| * drivers should _never_ use the all version - the bio may have been split |
| * before it got to the driver and the driver won't own all of it |
| */ |
| #define bio_for_each_segment_all(bvl, bio, iter) \ |
| for (bvl = bvec_init_iter_all(&iter); bio_next_segment((bio), &iter); ) |
| |
| static inline void bio_advance_iter(const struct bio *bio, |
| struct bvec_iter *iter, unsigned int bytes) |
| { |
| iter->bi_sector += bytes >> 9; |
| |
| if (bio_no_advance_iter(bio)) |
| iter->bi_size -= bytes; |
| else |
| bvec_iter_advance(bio->bi_io_vec, iter, bytes); |
| /* TODO: It is reasonable to complete bio with error here. */ |
| } |
| |
| /* @bytes should be less or equal to bvec[i->bi_idx].bv_len */ |
| static inline void bio_advance_iter_single(const struct bio *bio, |
| struct bvec_iter *iter, |
| unsigned int bytes) |
| { |
| iter->bi_sector += bytes >> 9; |
| |
| if (bio_no_advance_iter(bio)) |
| iter->bi_size -= bytes; |
| else |
| bvec_iter_advance_single(bio->bi_io_vec, iter, bytes); |
| } |
| |
| #define __bio_for_each_segment(bvl, bio, iter, start) \ |
| for (iter = (start); \ |
| (iter).bi_size && \ |
| ((bvl = bio_iter_iovec((bio), (iter))), 1); \ |
| bio_advance_iter_single((bio), &(iter), (bvl).bv_len)) |
| |
| #define bio_for_each_segment(bvl, bio, iter) \ |
| __bio_for_each_segment(bvl, bio, iter, (bio)->bi_iter) |
| |
| #define __bio_for_each_bvec(bvl, bio, iter, start) \ |
| for (iter = (start); \ |
| (iter).bi_size && \ |
| ((bvl = mp_bvec_iter_bvec((bio)->bi_io_vec, (iter))), 1); \ |
| bio_advance_iter_single((bio), &(iter), (bvl).bv_len)) |
| |
| /* iterate over multi-page bvec */ |
| #define bio_for_each_bvec(bvl, bio, iter) \ |
| __bio_for_each_bvec(bvl, bio, iter, (bio)->bi_iter) |
| |
| /* |
| * Iterate over all multi-page bvecs. Drivers shouldn't use this version for the |
| * same reasons as bio_for_each_segment_all(). |
| */ |
| #define bio_for_each_bvec_all(bvl, bio, i) \ |
| for (i = 0, bvl = bio_first_bvec_all(bio); \ |
| i < (bio)->bi_vcnt; i++, bvl++) \ |
| |
| #define bio_iter_last(bvec, iter) ((iter).bi_size == (bvec).bv_len) |
| |
| static inline unsigned bio_segments(struct bio *bio) |
| { |
| unsigned segs = 0; |
| struct bio_vec bv; |
| struct bvec_iter iter; |
| |
| /* |
| * We special case discard/write same/write zeroes, because they |
| * interpret bi_size differently: |
| */ |
| |
| switch (bio_op(bio)) { |
| case REQ_OP_DISCARD: |
| case REQ_OP_SECURE_ERASE: |
| case REQ_OP_WRITE_ZEROES: |
| return 0; |
| case REQ_OP_WRITE_SAME: |
| return 1; |
| default: |
| break; |
| } |
| |
| bio_for_each_segment(bv, bio, iter) |
| segs++; |
| |
| return segs; |
| } |
| |
| /* |
| * get a reference to a bio, so it won't disappear. the intended use is |
| * something like: |
| * |
| * bio_get(bio); |
| * submit_bio(rw, bio); |
| * if (bio->bi_flags ...) |
| * do_something |
| * bio_put(bio); |
| * |
| * without the bio_get(), it could potentially complete I/O before submit_bio |
| * returns. and then bio would be freed memory when if (bio->bi_flags ...) |
| * runs |
| */ |
| static inline void bio_get(struct bio *bio) |
| { |
| bio->bi_flags |= (1 << BIO_REFFED); |
| smp_mb__before_atomic(); |
| atomic_inc(&bio->__bi_cnt); |
| } |
| |
| static inline void bio_cnt_set(struct bio *bio, unsigned int count) |
| { |
| if (count != 1) { |
| bio->bi_flags |= (1 << BIO_REFFED); |
| smp_mb(); |
| } |
| atomic_set(&bio->__bi_cnt, count); |
| } |
| |
| static inline bool bio_flagged(struct bio *bio, unsigned int bit) |
| { |
| return (bio->bi_flags & (1U << bit)) != 0; |
| } |
| |
| static inline void bio_set_flag(struct bio *bio, unsigned int bit) |
| { |
| bio->bi_flags |= (1U << bit); |
| } |
| |
| static inline void bio_clear_flag(struct bio *bio, unsigned int bit) |
| { |
| bio->bi_flags &= ~(1U << bit); |
| } |
| |
| static inline void bio_get_first_bvec(struct bio *bio, struct bio_vec *bv) |
| { |
| *bv = bio_iovec(bio); |
| } |
| |
| static inline void bio_get_last_bvec(struct bio *bio, struct bio_vec *bv) |
| { |
| struct bvec_iter iter = bio->bi_iter; |
| int idx; |
| |
| if (unlikely(!bio_multiple_segments(bio))) { |
| *bv = bio_iovec(bio); |
| return; |
| } |
| |
| bio_advance_iter(bio, &iter, iter.bi_size); |
| |
| if (!iter.bi_bvec_done) |
| idx = iter.bi_idx - 1; |
| else /* in the middle of bvec */ |
| idx = iter.bi_idx; |
| |
| *bv = bio->bi_io_vec[idx]; |
| |
| /* |
| * iter.bi_bvec_done records actual length of the last bvec |
| * if this bio ends in the middle of one io vector |
| */ |
| if (iter.bi_bvec_done) |
| bv->bv_len = iter.bi_bvec_done; |
| } |
| |
| static inline struct bio_vec *bio_first_bvec_all(struct bio *bio) |
| { |
| WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED)); |
| return bio->bi_io_vec; |
| } |
| |
| static inline struct page *bio_first_page_all(struct bio *bio) |
| { |
| return bio_first_bvec_all(bio)->bv_page; |
| } |
| |
| static inline struct bio_vec *bio_last_bvec_all(struct bio *bio) |
| { |
| WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED)); |
| return &bio->bi_io_vec[bio->bi_vcnt - 1]; |
| } |
| |
| enum bip_flags { |
| BIP_BLOCK_INTEGRITY = 1 << 0, /* block layer owns integrity data */ |
| BIP_MAPPED_INTEGRITY = 1 << 1, /* ref tag has been remapped */ |
| BIP_CTRL_NOCHECK = 1 << 2, /* disable HBA integrity checking */ |
| BIP_DISK_NOCHECK = 1 << 3, /* disable disk integrity checking */ |
| BIP_IP_CHECKSUM = 1 << 4, /* IP checksum */ |
| }; |
| |
| /* |
| * bio integrity payload |
| */ |
| struct bio_integrity_payload { |
| struct bio *bip_bio; /* parent bio */ |
| |
| struct bvec_iter bip_iter; |
| |
| unsigned short bip_vcnt; /* # of integrity bio_vecs */ |
| unsigned short bip_max_vcnt; /* integrity bio_vec slots */ |
| unsigned short bip_flags; /* control flags */ |
| |
| struct bvec_iter bio_iter; /* for rewinding parent bio */ |
| |
| struct work_struct bip_work; /* I/O completion */ |
| |
| struct bio_vec *bip_vec; |
| struct bio_vec bip_inline_vecs[];/* embedded bvec array */ |
| }; |
| |
| #if defined(CONFIG_BLK_DEV_INTEGRITY) |
| |
| static inline struct bio_integrity_payload *bio_integrity(struct bio *bio) |
| { |
| if (bio->bi_opf & REQ_INTEGRITY) |
| return bio->bi_integrity; |
| |
| return NULL; |
| } |
| |
| static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag) |
| { |
| struct bio_integrity_payload *bip = bio_integrity(bio); |
| |
| if (bip) |
| return bip->bip_flags & flag; |
| |
| return false; |
| } |
| |
| static inline sector_t bip_get_seed(struct bio_integrity_payload *bip) |
| { |
| return bip->bip_iter.bi_sector; |
| } |
| |
| static inline void bip_set_seed(struct bio_integrity_payload *bip, |
| sector_t seed) |
| { |
| bip->bip_iter.bi_sector = seed; |
| } |
| |
| #endif /* CONFIG_BLK_DEV_INTEGRITY */ |
| |
| extern void bio_trim(struct bio *bio, int offset, int size); |
| extern struct bio *bio_split(struct bio *bio, int sectors, |
| gfp_t gfp, struct bio_set *bs); |
| |
| /** |
| * bio_next_split - get next @sectors from a bio, splitting if necessary |
| * @bio: bio to split |
| * @sectors: number of sectors to split from the front of @bio |
| * @gfp: gfp mask |
| * @bs: bio set to allocate from |
| * |
| * Returns a bio representing the next @sectors of @bio - if the bio is smaller |
| * than @sectors, returns the original bio unchanged. |
| */ |
| static inline struct bio *bio_next_split(struct bio *bio, int sectors, |
| gfp_t gfp, struct bio_set *bs) |
| { |
| if (sectors >= bio_sectors(bio)) |
| return bio; |
| |
| return bio_split(bio, sectors, gfp, bs); |
| } |
| |
| enum { |
| BIOSET_NEED_BVECS = BIT(0), |
| BIOSET_NEED_RESCUER = BIT(1), |
| }; |
| extern int bioset_init(struct bio_set *, unsigned int, unsigned int, int flags); |
| extern void bioset_exit(struct bio_set *); |
| extern int biovec_init_pool(mempool_t *pool, int pool_entries); |
| extern int bioset_init_from_src(struct bio_set *bs, struct bio_set *src); |
| |
| struct bio *bio_alloc_bioset(gfp_t gfp, unsigned short nr_iovecs, |
| struct bio_set *bs); |
| struct bio *bio_kmalloc(gfp_t gfp_mask, unsigned short nr_iovecs); |
| extern void bio_put(struct bio *); |
| |
| extern void __bio_clone_fast(struct bio *, struct bio *); |
| extern struct bio *bio_clone_fast(struct bio *, gfp_t, struct bio_set *); |
| |
| extern struct bio_set fs_bio_set; |
| |
| static inline struct bio *bio_alloc(gfp_t gfp_mask, unsigned short nr_iovecs) |
| { |
| return bio_alloc_bioset(gfp_mask, nr_iovecs, &fs_bio_set); |
| } |
| |
| extern blk_qc_t submit_bio(struct bio *); |
| |
| extern void bio_endio(struct bio *); |
| |
| static inline void bio_io_error(struct bio *bio) |
| { |
| bio->bi_status = BLK_STS_IOERR; |
| bio_endio(bio); |
| } |
| |
| static inline void bio_wouldblock_error(struct bio *bio) |
| { |
| bio_set_flag(bio, BIO_QUIET); |
| bio->bi_status = BLK_STS_AGAIN; |
| bio_endio(bio); |
| } |
| |
| /* |
| * Calculate number of bvec segments that should be allocated to fit data |
| * pointed by @iter. If @iter is backed by bvec it's going to be reused |
| * instead of allocating a new one. |
| */ |
| static inline int bio_iov_vecs_to_alloc(struct iov_iter *iter, int max_segs) |
| { |
| if (iov_iter_is_bvec(iter)) |
| return 0; |
| return iov_iter_npages(iter, max_segs); |
| } |
| |
| struct request_queue; |
| |
| extern int submit_bio_wait(struct bio *bio); |
| extern void bio_advance(struct bio *, unsigned); |
| |
| extern void bio_init(struct bio *bio, struct bio_vec *table, |
| unsigned short max_vecs); |
| extern void bio_uninit(struct bio *); |
| extern void bio_reset(struct bio *); |
| void bio_chain(struct bio *, struct bio *); |
| |
| extern int bio_add_page(struct bio *, struct page *, unsigned int,unsigned int); |
| extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *, |
| unsigned int, unsigned int); |
| int bio_add_zone_append_page(struct bio *bio, struct page *page, |
| unsigned int len, unsigned int offset); |
| bool __bio_try_merge_page(struct bio *bio, struct page *page, |
| unsigned int len, unsigned int off, bool *same_page); |
| void __bio_add_page(struct bio *bio, struct page *page, |
| unsigned int len, unsigned int off); |
| int bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter); |
| void bio_release_pages(struct bio *bio, bool mark_dirty); |
| extern void bio_set_pages_dirty(struct bio *bio); |
| extern void bio_check_pages_dirty(struct bio *bio); |
| |
| extern void bio_copy_data_iter(struct bio *dst, struct bvec_iter *dst_iter, |
| struct bio *src, struct bvec_iter *src_iter); |
| extern void bio_copy_data(struct bio *dst, struct bio *src); |
| extern void bio_list_copy_data(struct bio *dst, struct bio *src); |
| extern void bio_free_pages(struct bio *bio); |
| void zero_fill_bio_iter(struct bio *bio, struct bvec_iter iter); |
| void bio_truncate(struct bio *bio, unsigned new_size); |
| void guard_bio_eod(struct bio *bio); |
| |
| static inline void zero_fill_bio(struct bio *bio) |
| { |
| zero_fill_bio_iter(bio, bio->bi_iter); |
| } |
| |
| extern const char *bio_devname(struct bio *bio, char *buffer); |
| |
| #define bio_set_dev(bio, bdev) \ |
| do { \ |
| bio_clear_flag(bio, BIO_REMAPPED); \ |
| if ((bio)->bi_bdev != (bdev)) \ |
| bio_clear_flag(bio, BIO_THROTTLED); \ |
| (bio)->bi_bdev = (bdev); \ |
| bio_associate_blkg(bio); \ |
| } while (0) |
| |
| #define bio_copy_dev(dst, src) \ |
| do { \ |
| bio_clear_flag(dst, BIO_REMAPPED); \ |
| (dst)->bi_bdev = (src)->bi_bdev; \ |
| bio_clone_blkg_association(dst, src); \ |
| } while (0) |
| |
| #define bio_dev(bio) \ |
| disk_devt((bio)->bi_bdev->bd_disk) |
| |
| #ifdef CONFIG_BLK_CGROUP |
| void bio_associate_blkg(struct bio *bio); |
| void bio_associate_blkg_from_css(struct bio *bio, |
| struct cgroup_subsys_state *css); |
| void bio_clone_blkg_association(struct bio *dst, struct bio *src); |
| #else /* CONFIG_BLK_CGROUP */ |
| static inline void bio_associate_blkg(struct bio *bio) { } |
| static inline void bio_associate_blkg_from_css(struct bio *bio, |
| struct cgroup_subsys_state *css) |
| { } |
| static inline void bio_clone_blkg_association(struct bio *dst, |
| struct bio *src) { } |
| #endif /* CONFIG_BLK_CGROUP */ |
| |
| #ifdef CONFIG_HIGHMEM |
| /* |
| * remember never ever reenable interrupts between a bvec_kmap_irq and |
| * bvec_kunmap_irq! |
| */ |
| static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags) |
| { |
| unsigned long addr; |
| |
| /* |
| * might not be a highmem page, but the preempt/irq count |
| * balancing is a lot nicer this way |
| */ |
| local_irq_save(*flags); |
| addr = (unsigned long) kmap_atomic(bvec->bv_page); |
| |
| BUG_ON(addr & ~PAGE_MASK); |
| |
| return (char *) addr + bvec->bv_offset; |
| } |
| |
| static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags) |
| { |
| unsigned long ptr = (unsigned long) buffer & PAGE_MASK; |
| |
| kunmap_atomic((void *) ptr); |
| local_irq_restore(*flags); |
| } |
| |
| #else |
| static inline char *bvec_kmap_irq(struct bio_vec *bvec, unsigned long *flags) |
| { |
| return page_address(bvec->bv_page) + bvec->bv_offset; |
| } |
| |
| static inline void bvec_kunmap_irq(char *buffer, unsigned long *flags) |
| { |
| *flags = 0; |
| } |
| #endif |
| |
| /* |
| * BIO list management for use by remapping drivers (e.g. DM or MD) and loop. |
| * |
| * A bio_list anchors a singly-linked list of bios chained through the bi_next |
| * member of the bio. The bio_list also caches the last list member to allow |
| * fast access to the tail. |
| */ |
| struct bio_list { |
| struct bio *head; |
| struct bio *tail; |
| }; |
| |
| static inline int bio_list_empty(const struct bio_list *bl) |
| { |
| return bl->head == NULL; |
| } |
| |
| static inline void bio_list_init(struct bio_list *bl) |
| { |
| bl->head = bl->tail = NULL; |
| } |
| |
| #define BIO_EMPTY_LIST { NULL, NULL } |
| |
| #define bio_list_for_each(bio, bl) \ |
| for (bio = (bl)->head; bio; bio = bio->bi_next) |
| |
| static inline unsigned bio_list_size(const struct bio_list *bl) |
| { |
| unsigned sz = 0; |
| struct bio *bio; |
| |
| bio_list_for_each(bio, bl) |
| sz++; |
| |
| return sz; |
| } |
| |
| static inline void bio_list_add(struct bio_list *bl, struct bio *bio) |
| { |
| bio->bi_next = NULL; |
| |
| if (bl->tail) |
| bl->tail->bi_next = bio; |
| else |
| bl->head = bio; |
| |
| bl->tail = bio; |
| } |
| |
| static inline void bio_list_add_head(struct bio_list *bl, struct bio *bio) |
| { |
| bio->bi_next = bl->head; |
| |
| bl->head = bio; |
| |
| if (!bl->tail) |
| bl->tail = bio; |
| } |
| |
| static inline void bio_list_merge(struct bio_list *bl, struct bio_list *bl2) |
| { |
| if (!bl2->head) |
| return; |
| |
| if (bl->tail) |
| bl->tail->bi_next = bl2->head; |
| else |
| bl->head = bl2->head; |
| |
| bl->tail = bl2->tail; |
| } |
| |
| static inline void bio_list_merge_head(struct bio_list *bl, |
| struct bio_list *bl2) |
| { |
| if (!bl2->head) |
| return; |
| |
| if (bl->head) |
| bl2->tail->bi_next = bl->head; |
| else |
| bl->tail = bl2->tail; |
| |
| bl->head = bl2->head; |
| } |
| |
| static inline struct bio *bio_list_peek(struct bio_list *bl) |
| { |
| return bl->head; |
| } |
| |
| static inline struct bio *bio_list_pop(struct bio_list *bl) |
| { |
| struct bio *bio = bl->head; |
| |
| if (bio) { |
| bl->head = bl->head->bi_next; |
| if (!bl->head) |
| bl->tail = NULL; |
| |
| bio->bi_next = NULL; |
| } |
| |
| return bio; |
| } |
| |
| static inline struct bio *bio_list_get(struct bio_list *bl) |
| { |
| struct bio *bio = bl->head; |
| |
| bl->head = bl->tail = NULL; |
| |
| return bio; |
| } |
| |
| /* |
| * Increment chain count for the bio. Make sure the CHAIN flag update |
| * is visible before the raised count. |
| */ |
| static inline void bio_inc_remaining(struct bio *bio) |
| { |
| bio_set_flag(bio, BIO_CHAIN); |
| smp_mb__before_atomic(); |
| atomic_inc(&bio->__bi_remaining); |
| } |
| |
| /* |
| * 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[]. |
| */ |
| #define BIO_POOL_SIZE 2 |
| |
| struct bio_set { |
| struct kmem_cache *bio_slab; |
| unsigned int front_pad; |
| |
| mempool_t bio_pool; |
| mempool_t bvec_pool; |
| #if defined(CONFIG_BLK_DEV_INTEGRITY) |
| mempool_t bio_integrity_pool; |
| mempool_t bvec_integrity_pool; |
| #endif |
| |
| unsigned int back_pad; |
| /* |
| * Deadlock avoidance for stacking block drivers: see comments in |
| * bio_alloc_bioset() for details |
| */ |
| spinlock_t rescue_lock; |
| struct bio_list rescue_list; |
| struct work_struct rescue_work; |
| struct workqueue_struct *rescue_workqueue; |
| }; |
| |
| static inline bool bioset_initialized(struct bio_set *bs) |
| { |
| return bs->bio_slab != NULL; |
| } |
| |
| #if defined(CONFIG_BLK_DEV_INTEGRITY) |
| |
| #define bip_for_each_vec(bvl, bip, iter) \ |
| for_each_bvec(bvl, (bip)->bip_vec, iter, (bip)->bip_iter) |
| |
| #define bio_for_each_integrity_vec(_bvl, _bio, _iter) \ |
| for_each_bio(_bio) \ |
| bip_for_each_vec(_bvl, _bio->bi_integrity, _iter) |
| |
| extern struct bio_integrity_payload *bio_integrity_alloc(struct bio *, gfp_t, unsigned int); |
| extern int bio_integrity_add_page(struct bio *, struct page *, unsigned int, unsigned int); |
| extern bool bio_integrity_prep(struct bio *); |
| extern void bio_integrity_advance(struct bio *, unsigned int); |
| extern void bio_integrity_trim(struct bio *); |
| extern int bio_integrity_clone(struct bio *, struct bio *, gfp_t); |
| extern int bioset_integrity_create(struct bio_set *, int); |
| extern void bioset_integrity_free(struct bio_set *); |
| extern void bio_integrity_init(void); |
| |
| #else /* CONFIG_BLK_DEV_INTEGRITY */ |
| |
| static inline void *bio_integrity(struct bio *bio) |
| { |
| return NULL; |
| } |
| |
| static inline int bioset_integrity_create(struct bio_set *bs, int pool_size) |
| { |
| return 0; |
| } |
| |
| static inline void bioset_integrity_free (struct bio_set *bs) |
| { |
| return; |
| } |
| |
| static inline bool bio_integrity_prep(struct bio *bio) |
| { |
| return true; |
| } |
| |
| static inline int bio_integrity_clone(struct bio *bio, struct bio *bio_src, |
| gfp_t gfp_mask) |
| { |
| return 0; |
| } |
| |
| static inline void bio_integrity_advance(struct bio *bio, |
| unsigned int bytes_done) |
| { |
| return; |
| } |
| |
| static inline void bio_integrity_trim(struct bio *bio) |
| { |
| return; |
| } |
| |
| static inline void bio_integrity_init(void) |
| { |
| return; |
| } |
| |
| static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag) |
| { |
| return false; |
| } |
| |
| static inline void *bio_integrity_alloc(struct bio * bio, gfp_t gfp, |
| unsigned int nr) |
| { |
| return ERR_PTR(-EINVAL); |
| } |
| |
| static inline int bio_integrity_add_page(struct bio *bio, struct page *page, |
| unsigned int len, unsigned int offset) |
| { |
| return 0; |
| } |
| |
| #endif /* CONFIG_BLK_DEV_INTEGRITY */ |
| |
| /* |
| * Mark a bio as polled. Note that for async polled IO, the caller must |
| * expect -EWOULDBLOCK if we cannot allocate a request (or other resources). |
| * We cannot block waiting for requests on polled IO, as those completions |
| * must be found by the caller. This is different than IRQ driven IO, where |
| * it's safe to wait for IO to complete. |
| */ |
| static inline void bio_set_polled(struct bio *bio, struct kiocb *kiocb) |
| { |
| bio->bi_opf |= REQ_HIPRI; |
| if (!is_sync_kiocb(kiocb)) |
| bio->bi_opf |= REQ_NOWAIT; |
| } |
| |
| #endif /* __LINUX_BIO_H */ |