777 lines
20 KiB
C
Executable File
777 lines
20 KiB
C
Executable File
/*
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* 2.5 block I/O model
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*
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* Copyright (C) 2001 Jens Axboe <axboe@suse.de>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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*
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public Licens
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-
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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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#include <linux/bug.h>
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#ifdef CONFIG_BLOCK
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#include <asm/io.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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#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_MAX_SIZE (BIO_MAX_PAGES << PAGE_CACHE_SHIFT)
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#define BIO_MAX_SECTORS (BIO_MAX_SIZE >> 9)
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/*
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* upper 16 bits of bi_rw define the io priority of this bio
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*/
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#define BIO_PRIO_SHIFT (8 * sizeof(unsigned long) - IOPRIO_BITS)
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#define bio_prio(bio) ((bio)->bi_rw >> BIO_PRIO_SHIFT)
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#define bio_prio_valid(bio) ioprio_valid(bio_prio(bio))
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#define bio_set_prio(bio, prio) do { \
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WARN_ON(prio >= (1 << IOPRIO_BITS)); \
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(bio)->bi_rw &= ((1UL << BIO_PRIO_SHIFT) - 1); \
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(bio)->bi_rw |= ((unsigned long) (prio) << BIO_PRIO_SHIFT); \
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} while (0)
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/*
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* various member access, note that bio_data should of course not be used
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* on highmem page vectors
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*/
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#define __bvec_iter_bvec(bvec, iter) (&(bvec)[(iter).bi_idx])
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#define bvec_iter_page(bvec, iter) \
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(__bvec_iter_bvec((bvec), (iter))->bv_page)
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#define bvec_iter_len(bvec, iter) \
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min((iter).bi_size, \
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__bvec_iter_bvec((bvec), (iter))->bv_len - (iter).bi_bvec_done)
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#define bvec_iter_offset(bvec, iter) \
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(__bvec_iter_bvec((bvec), (iter))->bv_offset + (iter).bi_bvec_done)
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#define bvec_iter_bvec(bvec, iter) \
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((struct bio_vec) { \
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.bv_page = bvec_iter_page((bvec), (iter)), \
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.bv_len = bvec_iter_len((bvec), (iter)), \
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.bv_offset = bvec_iter_offset((bvec), (iter)), \
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})
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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 bio_sectors(bio) ((bio)->bi_iter.bi_size >> 9)
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#define bio_end_sector(bio) ((bio)->bi_iter.bi_sector + bio_sectors((bio)))
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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->bi_rw & REQ_DISCARD))
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return true;
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return false;
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}
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static inline bool bio_is_rw(struct bio *bio)
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{
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if (!bio_has_data(bio))
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return false;
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if (bio->bi_rw & BIO_NO_ADVANCE_ITER_MASK)
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return false;
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return true;
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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_rw & 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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* will die
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*/
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#define bio_to_phys(bio) (page_to_phys(bio_page((bio))) + (unsigned long) bio_offset((bio)))
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#define bvec_to_phys(bv) (page_to_phys((bv)->bv_page) + (unsigned long) (bv)->bv_offset)
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/*
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* queues that have highmem support enabled may still need to revert to
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* PIO transfers occasionally and thus map high pages temporarily. For
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* permanent PIO fall back, user is probably better off disabling highmem
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* I/O completely on that queue (see ide-dma for example)
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*/
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#define __bio_kmap_atomic(bio, iter) \
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(kmap_atomic(bio_iter_iovec((bio), (iter)).bv_page) + \
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bio_iter_iovec((bio), (iter)).bv_offset)
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#define __bio_kunmap_atomic(addr) kunmap_atomic(addr)
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/*
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* merge helpers etc
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*/
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/* Default implementation of BIOVEC_PHYS_MERGEABLE */
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#define __BIOVEC_PHYS_MERGEABLE(vec1, vec2) \
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((bvec_to_phys((vec1)) + (vec1)->bv_len) == bvec_to_phys((vec2)))
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/*
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* allow arch override, for eg virtualized architectures (put in asm/io.h)
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*/
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#ifndef BIOVEC_PHYS_MERGEABLE
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#define BIOVEC_PHYS_MERGEABLE(vec1, vec2) \
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__BIOVEC_PHYS_MERGEABLE(vec1, vec2)
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#endif
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#define __BIO_SEG_BOUNDARY(addr1, addr2, mask) \
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(((addr1) | (mask)) == (((addr2) - 1) | (mask)))
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#define BIOVEC_SEG_BOUNDARY(q, b1, b2) \
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__BIO_SEG_BOUNDARY(bvec_to_phys((b1)), bvec_to_phys((b2)) + (b2)->bv_len, queue_segment_boundary((q)))
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/*
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* Check if adding a bio_vec after bprv with offset would create a gap in
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* the SG list. Most drivers don't care about this, but some do.
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*/
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static inline bool bvec_gap_to_prev(struct bio_vec *bprv, unsigned int offset)
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{
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return offset || ((bprv->bv_offset + bprv->bv_len) & (PAGE_SIZE - 1));
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}
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#define bio_io_error(bio) bio_endio((bio), -EIO)
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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, i) \
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for (i = 0, bvl = (bio)->bi_io_vec; i < (bio)->bi_vcnt; i++, bvl++)
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static inline void bvec_iter_advance(struct bio_vec *bv, struct bvec_iter *iter,
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unsigned bytes)
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{
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WARN_ONCE(bytes > iter->bi_size,
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"Attempted to advance past end of bvec iter\n");
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while (bytes) {
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unsigned len = min(bytes, bvec_iter_len(bv, *iter));
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bytes -= len;
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iter->bi_size -= len;
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iter->bi_bvec_done += len;
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if (iter->bi_bvec_done == __bvec_iter_bvec(bv, *iter)->bv_len) {
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iter->bi_bvec_done = 0;
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iter->bi_idx++;
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}
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}
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}
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#define for_each_bvec(bvl, bio_vec, iter, start) \
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for (iter = (start); \
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(iter).bi_size && \
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((bvl = bvec_iter_bvec((bio_vec), (iter))), 1); \
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bvec_iter_advance((bio_vec), &(iter), (bvl).bv_len))
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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->bi_rw & BIO_NO_ADVANCE_ITER_MASK)
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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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}
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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_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, because they interpret bi_size
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* differently:
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*/
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if (bio->bi_rw & REQ_DISCARD)
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return 1;
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if (bio->bi_rw & REQ_WRITE_SAME)
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return 1;
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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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#define bio_get(bio) atomic_inc(&(bio)->bi_cnt)
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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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#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_rw & REQ_INTEGRITY)
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return bio->bi_integrity;
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return NULL;
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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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bio_end_io_t *bip_end_io; /* saved I/O completion fn */
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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 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[0];/* embedded bvec array */
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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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extern struct bio_set *bioset_create(unsigned int, unsigned int);
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extern struct bio_set *bioset_create_nobvec(unsigned int, unsigned int);
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extern void bioset_free(struct bio_set *);
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extern mempool_t *biovec_create_pool(int pool_entries);
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extern struct bio *bio_alloc_bioset(gfp_t, 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 *bio_clone_bioset(struct bio *, gfp_t, struct bio_set *bs);
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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_clone(struct bio *bio, gfp_t gfp_mask)
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{
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return bio_clone_bioset(bio, gfp_mask, 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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static inline struct bio *bio_clone_kmalloc(struct bio *bio, gfp_t gfp_mask)
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{
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return bio_clone_bioset(bio, gfp_mask, NULL);
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}
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extern void bio_endio(struct bio *, int);
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extern void bio_endio_nodec(struct bio *, int);
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struct request_queue;
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extern int bio_phys_segments(struct request_queue *, struct bio *);
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extern int submit_bio_wait(int rw, struct bio *bio);
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extern void bio_advance(struct bio *, unsigned);
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extern void bio_init(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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extern int bio_get_nr_vecs(struct block_device *);
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extern struct bio *bio_map_user(struct request_queue *, struct block_device *,
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unsigned long, unsigned int, int, gfp_t);
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struct sg_iovec;
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struct rq_map_data;
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extern struct bio *bio_map_user_iov(struct request_queue *,
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struct block_device *,
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const struct sg_iovec *, int, int, gfp_t);
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extern void bio_unmap_user(struct bio *);
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extern struct bio *bio_map_kern(struct request_queue *, void *, unsigned int,
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gfp_t);
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extern struct bio *bio_copy_kern(struct request_queue *, void *, unsigned int,
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gfp_t, int);
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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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#ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
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# error "You should define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE for your platform"
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#endif
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#if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE
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extern void bio_flush_dcache_pages(struct bio *bi);
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#else
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static inline void bio_flush_dcache_pages(struct bio *bi)
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{
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}
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#endif
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extern void bio_copy_data(struct bio *dst, struct bio *src);
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extern int bio_alloc_pages(struct bio *bio, gfp_t gfp);
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extern struct bio *bio_copy_user(struct request_queue *, struct rq_map_data *,
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unsigned long, unsigned int, int, gfp_t);
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extern struct bio *bio_copy_user_iov(struct request_queue *,
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struct rq_map_data *,
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const struct sg_iovec *,
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int, int, gfp_t);
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extern int bio_uncopy_user(struct bio *);
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void zero_fill_bio(struct bio *bio);
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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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#ifdef CONFIG_BLK_CGROUP
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int bio_associate_current(struct bio *bio);
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void bio_disassociate_task(struct bio *bio);
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#else /* CONFIG_BLK_CGROUP */
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static inline int bio_associate_current(struct bio *bio) { return -ENOENT; }
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static inline void bio_disassociate_task(struct bio *bio) { }
|
|
#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
|
|
|
|
static inline char *__bio_kmap_irq(struct bio *bio, struct bvec_iter iter,
|
|
unsigned long *flags)
|
|
{
|
|
return bvec_kmap_irq(&bio_iter_iovec(bio, iter), flags);
|
|
}
|
|
#define __bio_kunmap_irq(buf, flags) bvec_kunmap_irq(buf, flags)
|
|
|
|
#define bio_kmap_irq(bio, flags) \
|
|
__bio_kmap_irq((bio), (bio)->bi_iter, (flags))
|
|
#define bio_kunmap_irq(buf,flags) __bio_kunmap_irq(buf, flags)
|
|
|
|
/*
|
|
* 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;
|
|
}
|
|
|
|
/*
|
|
* 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
|
|
#define BIOVEC_NR_POOLS 6
|
|
#define BIOVEC_MAX_IDX (BIOVEC_NR_POOLS - 1)
|
|
|
|
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;
|
|
};
|
|
|
|
/*
|
|
* 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 void bio_integrity_free(struct bio *);
|
|
extern int bio_integrity_add_page(struct bio *, struct page *, unsigned int, unsigned int);
|
|
extern bool bio_integrity_enabled(struct bio *bio);
|
|
extern int bio_integrity_prep(struct bio *);
|
|
extern void bio_integrity_endio(struct bio *, int);
|
|
extern void bio_integrity_advance(struct bio *, unsigned int);
|
|
extern void bio_integrity_trim(struct bio *, unsigned int, unsigned int);
|
|
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 bool bio_integrity_enabled(struct bio *bio)
|
|
{
|
|
return false;
|
|
}
|
|
|
|
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 int bio_integrity_prep(struct bio *bio)
|
|
{
|
|
return 0;
|
|
}
|
|
|
|
static inline void bio_integrity_free(struct bio *bio)
|
|
{
|
|
return;
|
|
}
|
|
|
|
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, unsigned int offset,
|
|
unsigned int sectors)
|
|
{
|
|
return;
|
|
}
|
|
|
|
static inline void bio_integrity_init(void)
|
|
{
|
|
return;
|
|
}
|
|
|
|
static inline bool bio_integrity_flagged(struct bio *bio, enum bip_flags flag)
|
|
{
|
|
return false;
|
|
}
|
|
|
|
#endif /* CONFIG_BLK_DEV_INTEGRITY */
|
|
|
|
#endif /* CONFIG_BLOCK */
|
|
#endif /* __LINUX_BIO_H */
|