795 строки
20 KiB
C
795 строки
20 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
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/*
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* Copyright (C) 2001 Jens Axboe <axboe@suse.de>
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*/
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#ifndef __LINUX_BIO_H
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#define __LINUX_BIO_H
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#include <linux/mempool.h>
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/* struct bio, bio_vec and BIO_* flags are defined in blk_types.h */
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#include <linux/blk_types.h>
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#include <linux/uio.h>
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#define BIO_MAX_VECS 256U
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static inline unsigned int bio_max_segs(unsigned int nr_segs)
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{
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return min(nr_segs, BIO_MAX_VECS);
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}
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#define bio_prio(bio) (bio)->bi_ioprio
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#define bio_set_prio(bio, prio) ((bio)->bi_ioprio = prio)
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#define bio_iter_iovec(bio, iter) \
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bvec_iter_bvec((bio)->bi_io_vec, (iter))
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#define bio_iter_page(bio, iter) \
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bvec_iter_page((bio)->bi_io_vec, (iter))
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#define bio_iter_len(bio, iter) \
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bvec_iter_len((bio)->bi_io_vec, (iter))
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#define bio_iter_offset(bio, iter) \
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bvec_iter_offset((bio)->bi_io_vec, (iter))
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#define bio_page(bio) bio_iter_page((bio), (bio)->bi_iter)
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#define bio_offset(bio) bio_iter_offset((bio), (bio)->bi_iter)
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#define bio_iovec(bio) bio_iter_iovec((bio), (bio)->bi_iter)
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#define bvec_iter_sectors(iter) ((iter).bi_size >> 9)
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#define bvec_iter_end_sector(iter) ((iter).bi_sector + bvec_iter_sectors((iter)))
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#define bio_sectors(bio) bvec_iter_sectors((bio)->bi_iter)
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#define bio_end_sector(bio) bvec_iter_end_sector((bio)->bi_iter)
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/*
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* Return the data direction, READ or WRITE.
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*/
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#define bio_data_dir(bio) \
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(op_is_write(bio_op(bio)) ? WRITE : READ)
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/*
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* Check whether this bio carries any data or not. A NULL bio is allowed.
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*/
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static inline bool bio_has_data(struct bio *bio)
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{
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if (bio &&
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bio->bi_iter.bi_size &&
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bio_op(bio) != REQ_OP_DISCARD &&
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bio_op(bio) != REQ_OP_SECURE_ERASE &&
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bio_op(bio) != REQ_OP_WRITE_ZEROES)
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return true;
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return false;
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}
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static inline bool bio_no_advance_iter(const struct bio *bio)
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{
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return bio_op(bio) == REQ_OP_DISCARD ||
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bio_op(bio) == REQ_OP_SECURE_ERASE ||
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bio_op(bio) == REQ_OP_WRITE_ZEROES;
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}
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static inline void *bio_data(struct bio *bio)
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{
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if (bio_has_data(bio))
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return page_address(bio_page(bio)) + bio_offset(bio);
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return NULL;
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}
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static inline bool bio_next_segment(const struct bio *bio,
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struct bvec_iter_all *iter)
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{
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if (iter->idx >= bio->bi_vcnt)
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return false;
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bvec_advance(&bio->bi_io_vec[iter->idx], iter);
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return true;
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}
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/*
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* drivers should _never_ use the all version - the bio may have been split
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* before it got to the driver and the driver won't own all of it
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*/
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#define bio_for_each_segment_all(bvl, bio, iter) \
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for (bvl = bvec_init_iter_all(&iter); bio_next_segment((bio), &iter); )
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static inline void bio_advance_iter(const struct bio *bio,
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struct bvec_iter *iter, unsigned int bytes)
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{
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iter->bi_sector += bytes >> 9;
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if (bio_no_advance_iter(bio))
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iter->bi_size -= bytes;
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else
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bvec_iter_advance(bio->bi_io_vec, iter, bytes);
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/* TODO: It is reasonable to complete bio with error here. */
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}
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/* @bytes should be less or equal to bvec[i->bi_idx].bv_len */
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static inline void bio_advance_iter_single(const struct bio *bio,
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struct bvec_iter *iter,
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unsigned int bytes)
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{
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iter->bi_sector += bytes >> 9;
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if (bio_no_advance_iter(bio))
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iter->bi_size -= bytes;
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else
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bvec_iter_advance_single(bio->bi_io_vec, iter, bytes);
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}
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void __bio_advance(struct bio *, unsigned bytes);
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/**
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* bio_advance - increment/complete a bio by some number of bytes
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* @bio: bio to advance
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* @nbytes: number of bytes to complete
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*
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* This updates bi_sector, bi_size and bi_idx; if the number of bytes to
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* complete doesn't align with a bvec boundary, then bv_len and bv_offset will
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* be updated on the last bvec as well.
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*
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* @bio will then represent the remaining, uncompleted portion of the io.
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*/
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static inline void bio_advance(struct bio *bio, unsigned int nbytes)
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{
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if (nbytes == bio->bi_iter.bi_size) {
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bio->bi_iter.bi_size = 0;
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return;
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}
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__bio_advance(bio, nbytes);
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}
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#define __bio_for_each_segment(bvl, bio, iter, start) \
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for (iter = (start); \
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(iter).bi_size && \
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((bvl = bio_iter_iovec((bio), (iter))), 1); \
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bio_advance_iter_single((bio), &(iter), (bvl).bv_len))
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#define bio_for_each_segment(bvl, bio, iter) \
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__bio_for_each_segment(bvl, bio, iter, (bio)->bi_iter)
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#define __bio_for_each_bvec(bvl, bio, iter, start) \
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for (iter = (start); \
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(iter).bi_size && \
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((bvl = mp_bvec_iter_bvec((bio)->bi_io_vec, (iter))), 1); \
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bio_advance_iter_single((bio), &(iter), (bvl).bv_len))
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/* iterate over multi-page bvec */
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#define bio_for_each_bvec(bvl, bio, iter) \
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__bio_for_each_bvec(bvl, bio, iter, (bio)->bi_iter)
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/*
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* Iterate over all multi-page bvecs. Drivers shouldn't use this version for the
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* same reasons as bio_for_each_segment_all().
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*/
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#define bio_for_each_bvec_all(bvl, bio, i) \
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for (i = 0, bvl = bio_first_bvec_all(bio); \
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i < (bio)->bi_vcnt; i++, bvl++)
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#define bio_iter_last(bvec, iter) ((iter).bi_size == (bvec).bv_len)
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static inline unsigned bio_segments(struct bio *bio)
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{
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unsigned segs = 0;
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struct bio_vec bv;
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struct bvec_iter iter;
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/*
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* We special case discard/write same/write zeroes, because they
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* interpret bi_size differently:
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*/
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switch (bio_op(bio)) {
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case REQ_OP_DISCARD:
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case REQ_OP_SECURE_ERASE:
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case REQ_OP_WRITE_ZEROES:
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return 0;
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default:
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break;
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}
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bio_for_each_segment(bv, bio, iter)
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segs++;
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return segs;
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}
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/*
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* get a reference to a bio, so it won't disappear. the intended use is
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* something like:
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*
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* bio_get(bio);
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* submit_bio(rw, bio);
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* if (bio->bi_flags ...)
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* do_something
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* bio_put(bio);
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*
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* without the bio_get(), it could potentially complete I/O before submit_bio
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* returns. and then bio would be freed memory when if (bio->bi_flags ...)
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* runs
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*/
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static inline void bio_get(struct bio *bio)
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{
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bio->bi_flags |= (1 << BIO_REFFED);
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smp_mb__before_atomic();
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atomic_inc(&bio->__bi_cnt);
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}
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static inline void bio_cnt_set(struct bio *bio, unsigned int count)
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{
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if (count != 1) {
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bio->bi_flags |= (1 << BIO_REFFED);
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smp_mb();
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}
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atomic_set(&bio->__bi_cnt, count);
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}
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static inline bool bio_flagged(struct bio *bio, unsigned int bit)
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{
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return (bio->bi_flags & (1U << bit)) != 0;
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}
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static inline void bio_set_flag(struct bio *bio, unsigned int bit)
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{
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bio->bi_flags |= (1U << bit);
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}
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static inline void bio_clear_flag(struct bio *bio, unsigned int bit)
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{
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bio->bi_flags &= ~(1U << bit);
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}
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static inline struct bio_vec *bio_first_bvec_all(struct bio *bio)
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{
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WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED));
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return bio->bi_io_vec;
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}
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static inline struct page *bio_first_page_all(struct bio *bio)
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{
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return bio_first_bvec_all(bio)->bv_page;
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}
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static inline struct bio_vec *bio_last_bvec_all(struct bio *bio)
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{
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WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED));
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return &bio->bi_io_vec[bio->bi_vcnt - 1];
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}
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/**
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* struct folio_iter - State for iterating all folios in a bio.
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* @folio: The current folio we're iterating. NULL after the last folio.
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* @offset: The byte offset within the current folio.
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* @length: The number of bytes in this iteration (will not cross folio
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* boundary).
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*/
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struct folio_iter {
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struct folio *folio;
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size_t offset;
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size_t length;
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/* private: for use by the iterator */
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struct folio *_next;
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size_t _seg_count;
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int _i;
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};
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static inline void bio_first_folio(struct folio_iter *fi, struct bio *bio,
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int i)
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{
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struct bio_vec *bvec = bio_first_bvec_all(bio) + i;
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fi->folio = page_folio(bvec->bv_page);
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fi->offset = bvec->bv_offset +
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PAGE_SIZE * (bvec->bv_page - &fi->folio->page);
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fi->_seg_count = bvec->bv_len;
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fi->length = min(folio_size(fi->folio) - fi->offset, fi->_seg_count);
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fi->_next = folio_next(fi->folio);
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fi->_i = i;
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}
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static inline void bio_next_folio(struct folio_iter *fi, struct bio *bio)
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{
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fi->_seg_count -= fi->length;
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if (fi->_seg_count) {
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fi->folio = fi->_next;
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fi->offset = 0;
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fi->length = min(folio_size(fi->folio), fi->_seg_count);
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fi->_next = folio_next(fi->folio);
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} else if (fi->_i + 1 < bio->bi_vcnt) {
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bio_first_folio(fi, bio, fi->_i + 1);
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} else {
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fi->folio = NULL;
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}
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}
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/**
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* bio_for_each_folio_all - Iterate over each folio in a bio.
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* @fi: struct folio_iter which is updated for each folio.
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* @bio: struct bio to iterate over.
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*/
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#define bio_for_each_folio_all(fi, bio) \
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for (bio_first_folio(&fi, bio, 0); fi.folio; bio_next_folio(&fi, bio))
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enum bip_flags {
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BIP_BLOCK_INTEGRITY = 1 << 0, /* block layer owns integrity data */
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BIP_MAPPED_INTEGRITY = 1 << 1, /* ref tag has been remapped */
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BIP_CTRL_NOCHECK = 1 << 2, /* disable HBA integrity checking */
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BIP_DISK_NOCHECK = 1 << 3, /* disable disk integrity checking */
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BIP_IP_CHECKSUM = 1 << 4, /* IP checksum */
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};
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/*
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* bio integrity payload
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*/
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struct bio_integrity_payload {
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struct bio *bip_bio; /* parent bio */
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struct bvec_iter bip_iter;
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unsigned short bip_vcnt; /* # of integrity bio_vecs */
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unsigned short bip_max_vcnt; /* integrity bio_vec slots */
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unsigned short bip_flags; /* control flags */
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struct bvec_iter bio_iter; /* for rewinding parent bio */
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struct work_struct bip_work; /* I/O completion */
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struct bio_vec *bip_vec;
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struct bio_vec bip_inline_vecs[];/* embedded bvec array */
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};
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#if defined(CONFIG_BLK_DEV_INTEGRITY)
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static inline struct bio_integrity_payload *bio_integrity(struct bio *bio)
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{
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if (bio->bi_opf & REQ_INTEGRITY)
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return bio->bi_integrity;
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return NULL;
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}
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static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag)
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{
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struct bio_integrity_payload *bip = bio_integrity(bio);
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if (bip)
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return bip->bip_flags & flag;
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return false;
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}
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static inline sector_t bip_get_seed(struct bio_integrity_payload *bip)
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{
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return bip->bip_iter.bi_sector;
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}
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static inline void bip_set_seed(struct bio_integrity_payload *bip,
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sector_t seed)
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{
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bip->bip_iter.bi_sector = seed;
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}
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#endif /* CONFIG_BLK_DEV_INTEGRITY */
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void bio_trim(struct bio *bio, sector_t offset, sector_t size);
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extern struct bio *bio_split(struct bio *bio, int sectors,
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gfp_t gfp, struct bio_set *bs);
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/**
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* bio_next_split - get next @sectors from a bio, splitting if necessary
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* @bio: bio to split
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* @sectors: number of sectors to split from the front of @bio
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* @gfp: gfp mask
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* @bs: bio set to allocate from
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*
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* Return: a bio representing the next @sectors of @bio - if the bio is smaller
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* than @sectors, returns the original bio unchanged.
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*/
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static inline struct bio *bio_next_split(struct bio *bio, int sectors,
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gfp_t gfp, struct bio_set *bs)
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{
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if (sectors >= bio_sectors(bio))
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return bio;
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return bio_split(bio, sectors, gfp, bs);
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}
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enum {
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BIOSET_NEED_BVECS = BIT(0),
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BIOSET_NEED_RESCUER = BIT(1),
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BIOSET_PERCPU_CACHE = BIT(2),
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};
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extern int bioset_init(struct bio_set *, unsigned int, unsigned int, int flags);
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extern void bioset_exit(struct bio_set *);
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extern int biovec_init_pool(mempool_t *pool, int pool_entries);
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struct bio *bio_alloc_bioset(struct block_device *bdev, unsigned short nr_vecs,
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blk_opf_t opf, gfp_t gfp_mask,
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struct bio_set *bs);
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struct bio *bio_kmalloc(unsigned short nr_vecs, gfp_t gfp_mask);
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extern void bio_put(struct bio *);
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struct bio *bio_alloc_clone(struct block_device *bdev, struct bio *bio_src,
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gfp_t gfp, struct bio_set *bs);
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int bio_init_clone(struct block_device *bdev, struct bio *bio,
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struct bio *bio_src, gfp_t gfp);
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extern struct bio_set fs_bio_set;
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static inline struct bio *bio_alloc(struct block_device *bdev,
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unsigned short nr_vecs, blk_opf_t opf, gfp_t gfp_mask)
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{
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return bio_alloc_bioset(bdev, nr_vecs, opf, gfp_mask, &fs_bio_set);
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}
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void submit_bio(struct bio *bio);
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extern void bio_endio(struct bio *);
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static inline void bio_io_error(struct bio *bio)
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{
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bio->bi_status = BLK_STS_IOERR;
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bio_endio(bio);
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}
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static inline void bio_wouldblock_error(struct bio *bio)
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{
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bio_set_flag(bio, BIO_QUIET);
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bio->bi_status = BLK_STS_AGAIN;
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bio_endio(bio);
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}
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/*
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* Calculate number of bvec segments that should be allocated to fit data
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* pointed by @iter. If @iter is backed by bvec it's going to be reused
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* instead of allocating a new one.
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*/
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static inline int bio_iov_vecs_to_alloc(struct iov_iter *iter, int max_segs)
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{
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if (iov_iter_is_bvec(iter))
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return 0;
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return iov_iter_npages(iter, max_segs);
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}
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struct request_queue;
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extern int submit_bio_wait(struct bio *bio);
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void bio_init(struct bio *bio, struct block_device *bdev, struct bio_vec *table,
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unsigned short max_vecs, blk_opf_t opf);
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extern void bio_uninit(struct bio *);
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void bio_reset(struct bio *bio, struct block_device *bdev, blk_opf_t opf);
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void bio_chain(struct bio *, struct bio *);
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int bio_add_page(struct bio *, struct page *, unsigned len, unsigned off);
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bool bio_add_folio(struct bio *, struct folio *, size_t len, size_t off);
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extern int bio_add_pc_page(struct request_queue *, struct bio *, struct page *,
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unsigned int, unsigned int);
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int bio_add_zone_append_page(struct bio *bio, struct page *page,
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unsigned int len, unsigned int offset);
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void __bio_add_page(struct bio *bio, struct page *page,
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unsigned int len, unsigned int off);
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int bio_iov_iter_get_pages(struct bio *bio, struct iov_iter *iter);
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void bio_iov_bvec_set(struct bio *bio, struct iov_iter *iter);
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void __bio_release_pages(struct bio *bio, bool mark_dirty);
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extern void bio_set_pages_dirty(struct bio *bio);
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extern void bio_check_pages_dirty(struct bio *bio);
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extern void bio_copy_data_iter(struct bio *dst, struct bvec_iter *dst_iter,
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struct bio *src, struct bvec_iter *src_iter);
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extern void bio_copy_data(struct bio *dst, struct bio *src);
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extern void bio_free_pages(struct bio *bio);
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void guard_bio_eod(struct bio *bio);
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void zero_fill_bio(struct bio *bio);
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static inline void bio_release_pages(struct bio *bio, bool mark_dirty)
|
|
{
|
|
if (!bio_flagged(bio, BIO_NO_PAGE_REF))
|
|
__bio_release_pages(bio, mark_dirty);
|
|
}
|
|
|
|
#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 */
|
|
|
|
static inline void bio_set_dev(struct bio *bio, struct block_device *bdev)
|
|
{
|
|
bio_clear_flag(bio, BIO_REMAPPED);
|
|
if (bio->bi_bdev != bdev)
|
|
bio_clear_flag(bio, BIO_BPS_THROTTLED);
|
|
bio->bi_bdev = bdev;
|
|
bio_associate_blkg(bio);
|
|
}
|
|
|
|
/*
|
|
* 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;
|
|
|
|
/*
|
|
* per-cpu bio alloc cache
|
|
*/
|
|
struct bio_alloc_cache __percpu *cache;
|
|
|
|
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;
|
|
|
|
/*
|
|
* Hot un-plug notifier for the per-cpu cache, if used
|
|
*/
|
|
struct hlist_node cpuhp_dead;
|
|
};
|
|
|
|
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_POLLED;
|
|
if (!is_sync_kiocb(kiocb))
|
|
bio->bi_opf |= REQ_NOWAIT;
|
|
}
|
|
|
|
static inline void bio_clear_polled(struct bio *bio)
|
|
{
|
|
/* can't support alloc cache if we turn off polling */
|
|
bio->bi_opf &= ~(REQ_POLLED | REQ_ALLOC_CACHE);
|
|
}
|
|
|
|
struct bio *blk_next_bio(struct bio *bio, struct block_device *bdev,
|
|
unsigned int nr_pages, blk_opf_t opf, gfp_t gfp);
|
|
|
|
#endif /* __LINUX_BIO_H */
|