mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-10-31 16:38:12 +00:00
0a368bf00e
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293
("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
825 lines
20 KiB
C
825 lines
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/highmem.h>
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#include <linux/mempool.h>
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#include <linux/ioprio.h>
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#ifdef CONFIG_BLOCK
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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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#define BIO_DEBUG
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#ifdef BIO_DEBUG
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#define BIO_BUG_ON BUG_ON
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#else
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#define BIO_BUG_ON
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#endif
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#define BIO_MAX_PAGES 256
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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 bio_multiple_segments(bio) \
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((bio)->bi_iter.bi_size != bio_iovec(bio).bv_len)
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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(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_SAME ||
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bio_op(bio) == REQ_OP_WRITE_ZEROES;
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}
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static inline bool bio_mergeable(struct bio *bio)
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{
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if (bio->bi_opf & REQ_NOMERGE_FLAGS)
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return false;
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return true;
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}
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static inline unsigned int bio_cur_bytes(struct bio *bio)
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{
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if (bio_has_data(bio))
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return bio_iovec(bio).bv_len;
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else /* dataless requests such as discard */
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return bio->bi_iter.bi_size;
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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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/**
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* bio_full - check if the bio is full
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* @bio: bio to check
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* @len: length of one segment to be added
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*
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* Return true if @bio is full and one segment with @len bytes can't be
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* added to the bio, otherwise return false
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*/
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static inline bool bio_full(struct bio *bio, unsigned len)
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{
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if (bio->bi_vcnt >= bio->bi_max_vecs)
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return true;
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if (bio->bi_iter.bi_size > UINT_MAX - len)
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return true;
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return false;
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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(struct bio *bio, struct bvec_iter *iter,
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unsigned 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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#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((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((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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#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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case REQ_OP_WRITE_SAME:
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return 1;
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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 void bio_get_first_bvec(struct bio *bio, struct bio_vec *bv)
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{
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*bv = bio_iovec(bio);
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}
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static inline void bio_get_last_bvec(struct bio *bio, struct bio_vec *bv)
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{
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struct bvec_iter iter = bio->bi_iter;
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int idx;
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if (unlikely(!bio_multiple_segments(bio))) {
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*bv = bio_iovec(bio);
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return;
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}
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bio_advance_iter(bio, &iter, iter.bi_size);
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if (!iter.bi_bvec_done)
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idx = iter.bi_idx - 1;
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else /* in the middle of bvec */
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idx = iter.bi_idx;
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*bv = bio->bi_io_vec[idx];
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/*
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* iter.bi_bvec_done records actual length of the last bvec
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* if this bio ends in the middle of one io vector
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*/
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if (iter.bi_bvec_done)
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bv->bv_len = iter.bi_bvec_done;
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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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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_slab; /* slab the bip came from */
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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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extern void bio_trim(struct bio *bio, int offset, int 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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* Returns 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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};
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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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extern int bioset_init_from_src(struct bio_set *bs, struct bio_set *src);
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extern struct bio *bio_alloc_bioset(gfp_t, unsigned int, struct bio_set *);
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extern void bio_put(struct bio *);
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extern void __bio_clone_fast(struct bio *, struct bio *);
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extern struct bio *bio_clone_fast(struct bio *, gfp_t, struct bio_set *);
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extern struct bio_set fs_bio_set;
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static inline struct bio *bio_alloc(gfp_t gfp_mask, unsigned int nr_iovecs)
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{
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return bio_alloc_bioset(gfp_mask, nr_iovecs, &fs_bio_set);
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}
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static inline struct bio *bio_kmalloc(gfp_t gfp_mask, unsigned int nr_iovecs)
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{
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return bio_alloc_bioset(gfp_mask, nr_iovecs, NULL);
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}
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extern blk_qc_t submit_bio(struct 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->bi_status = BLK_STS_AGAIN;
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bio_endio(bio);
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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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extern void bio_advance(struct bio *, unsigned);
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extern void bio_init(struct bio *bio, struct bio_vec *table,
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unsigned short max_vecs);
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extern void bio_uninit(struct bio *);
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extern void bio_reset(struct bio *);
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void bio_chain(struct bio *, struct bio *);
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extern int bio_add_page(struct bio *, struct page *, unsigned int,unsigned int);
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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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bool __bio_try_merge_page(struct bio *bio, struct page *page,
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unsigned int len, unsigned int off, bool *same_page);
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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_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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void generic_start_io_acct(struct request_queue *q, int op,
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unsigned long sectors, struct hd_struct *part);
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void generic_end_io_acct(struct request_queue *q, int op,
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struct hd_struct *part,
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unsigned long start_time);
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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_list_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 zero_fill_bio_iter(struct bio *bio, struct bvec_iter iter);
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void bio_truncate(struct bio *bio, unsigned new_size);
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void guard_bio_eod(struct bio *bio);
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static inline void zero_fill_bio(struct bio *bio)
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{
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zero_fill_bio_iter(bio, bio->bi_iter);
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}
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extern struct bio_vec *bvec_alloc(gfp_t, int, unsigned long *, mempool_t *);
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extern void bvec_free(mempool_t *, struct bio_vec *, unsigned int);
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extern unsigned int bvec_nr_vecs(unsigned short idx);
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extern const char *bio_devname(struct bio *bio, char *buffer);
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#define bio_set_dev(bio, bdev) \
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do { \
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if ((bio)->bi_disk != (bdev)->bd_disk) \
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bio_clear_flag(bio, BIO_THROTTLED);\
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(bio)->bi_disk = (bdev)->bd_disk; \
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(bio)->bi_partno = (bdev)->bd_partno; \
|
|
bio_associate_blkg(bio); \
|
|
} while (0)
|
|
|
|
#define bio_copy_dev(dst, src) \
|
|
do { \
|
|
(dst)->bi_disk = (src)->bi_disk; \
|
|
(dst)->bi_partno = (src)->bi_partno; \
|
|
bio_clone_blkg_association(dst, src); \
|
|
} while (0)
|
|
|
|
#define bio_dev(bio) \
|
|
disk_devt((bio)->bi_disk)
|
|
|
|
#if defined(CONFIG_MEMCG) && defined(CONFIG_BLK_CGROUP)
|
|
void bio_associate_blkg_from_page(struct bio *bio, struct page *page);
|
|
#else
|
|
static inline void bio_associate_blkg_from_page(struct bio *bio,
|
|
struct page *page) { }
|
|
#endif
|
|
|
|
#ifdef CONFIG_BLK_CGROUP
|
|
void bio_disassociate_blkg(struct bio *bio);
|
|
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_disassociate_blkg(struct bio *bio) { }
|
|
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
|
|
|
|
/*
|
|
* 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;
|
|
};
|
|
|
|
struct biovec_slab {
|
|
int nr_vecs;
|
|
char *name;
|
|
struct kmem_cache *slab;
|
|
};
|
|
|
|
static inline bool bioset_initialized(struct bio_set *bs)
|
|
{
|
|
return bs->bio_slab != NULL;
|
|
}
|
|
|
|
/*
|
|
* a small number of entries is fine, not going to be performance critical.
|
|
* basically we just need to survive
|
|
*/
|
|
#define BIO_SPLIT_ENTRIES 2
|
|
|
|
#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 /* CONFIG_BLOCK */
|
|
#endif /* __LINUX_BIO_H */
|