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13685a1654
Introduce bio_list_peek(), to obtain a pointer to the first bio on the bio_list without actually removing it from the list. This is needed when you want to serialize based on the list being empty or not. Signed-off-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com> Acked-by: Jens Axboe <axboe@kernel.dk> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
668 lines
20 KiB
C
668 lines
20 KiB
C
/*
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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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* 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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#ifdef CONFIG_BLOCK
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#include <asm/io.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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* was unsigned short, but we might as well be ready for > 64kB I/O pages
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*/
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struct bio_vec {
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struct page *bv_page;
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unsigned int bv_len;
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unsigned int bv_offset;
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};
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struct bio_set;
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struct bio;
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struct bio_integrity_payload;
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typedef void (bio_end_io_t) (struct bio *, int);
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typedef void (bio_destructor_t) (struct bio *);
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/*
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* main unit of I/O for the block layer and lower layers (ie drivers and
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* stacking drivers)
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*/
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struct bio {
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sector_t bi_sector; /* device address in 512 byte
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sectors */
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struct bio *bi_next; /* request queue link */
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struct block_device *bi_bdev;
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unsigned long bi_flags; /* status, command, etc */
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unsigned long bi_rw; /* bottom bits READ/WRITE,
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* top bits priority
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*/
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unsigned short bi_vcnt; /* how many bio_vec's */
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unsigned short bi_idx; /* current index into bvl_vec */
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/* Number of segments in this BIO after
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* physical address coalescing is performed.
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*/
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unsigned int bi_phys_segments;
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unsigned int bi_size; /* residual I/O count */
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/*
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* To keep track of the max segment size, we account for the
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* sizes of the first and last mergeable segments in this bio.
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*/
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unsigned int bi_seg_front_size;
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unsigned int bi_seg_back_size;
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unsigned int bi_max_vecs; /* max bvl_vecs we can hold */
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unsigned int bi_comp_cpu; /* completion CPU */
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atomic_t bi_cnt; /* pin count */
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struct bio_vec *bi_io_vec; /* the actual vec list */
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bio_end_io_t *bi_end_io;
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void *bi_private;
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#if defined(CONFIG_BLK_DEV_INTEGRITY)
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struct bio_integrity_payload *bi_integrity; /* data integrity */
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#endif
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bio_destructor_t *bi_destructor; /* destructor */
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/*
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* We can inline a number of vecs at the end of the bio, to avoid
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* double allocations for a small number of bio_vecs. This member
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* MUST obviously be kept at the very end of the bio.
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*/
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struct bio_vec bi_inline_vecs[0];
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};
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/*
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* bio flags
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*/
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#define BIO_UPTODATE 0 /* ok after I/O completion */
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#define BIO_RW_BLOCK 1 /* RW_AHEAD set, and read/write would block */
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#define BIO_EOF 2 /* out-out-bounds error */
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#define BIO_SEG_VALID 3 /* bi_phys_segments valid */
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#define BIO_CLONED 4 /* doesn't own data */
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#define BIO_BOUNCED 5 /* bio is a bounce bio */
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#define BIO_USER_MAPPED 6 /* contains user pages */
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#define BIO_EOPNOTSUPP 7 /* not supported */
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#define BIO_CPU_AFFINE 8 /* complete bio on same CPU as submitted */
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#define BIO_NULL_MAPPED 9 /* contains invalid user pages */
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#define BIO_FS_INTEGRITY 10 /* fs owns integrity data, not block layer */
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#define BIO_QUIET 11 /* Make BIO Quiet */
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#define bio_flagged(bio, flag) ((bio)->bi_flags & (1 << (flag)))
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/*
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* top 4 bits of bio flags indicate the pool this bio came from
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*/
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#define BIO_POOL_BITS (4)
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#define BIO_POOL_NONE ((1UL << BIO_POOL_BITS) - 1)
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#define BIO_POOL_OFFSET (BITS_PER_LONG - BIO_POOL_BITS)
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#define BIO_POOL_MASK (1UL << BIO_POOL_OFFSET)
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#define BIO_POOL_IDX(bio) ((bio)->bi_flags >> BIO_POOL_OFFSET)
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/*
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* bio bi_rw flags
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*
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* bit 0 -- data direction
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* If not set, bio is a read from device. If set, it's a write to device.
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* bit 1 -- rw-ahead when set
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* bit 2 -- barrier
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* Insert a serialization point in the IO queue, forcing previously
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* submitted IO to be completed before this one is issued.
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* bit 3 -- synchronous I/O hint.
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* bit 4 -- Unplug the device immediately after submitting this bio.
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* bit 5 -- metadata request
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* Used for tracing to differentiate metadata and data IO. May also
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* get some preferential treatment in the IO scheduler
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* bit 6 -- discard sectors
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* Informs the lower level device that this range of sectors is no longer
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* used by the file system and may thus be freed by the device. Used
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* for flash based storage.
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* bit 7 -- fail fast device errors
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* bit 8 -- fail fast transport errors
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* bit 9 -- fail fast driver errors
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* Don't want driver retries for any fast fail whatever the reason.
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* bit 10 -- Tell the IO scheduler not to wait for more requests after this
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one has been submitted, even if it is a SYNC request.
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*/
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#define BIO_RW 0 /* Must match RW in req flags (blkdev.h) */
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#define BIO_RW_AHEAD 1 /* Must match FAILFAST in req flags */
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#define BIO_RW_BARRIER 2
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#define BIO_RW_SYNCIO 3
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#define BIO_RW_UNPLUG 4
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#define BIO_RW_META 5
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#define BIO_RW_DISCARD 6
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#define BIO_RW_FAILFAST_DEV 7
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#define BIO_RW_FAILFAST_TRANSPORT 8
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#define BIO_RW_FAILFAST_DRIVER 9
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#define BIO_RW_NOIDLE 10
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#define bio_rw_flagged(bio, flag) ((bio)->bi_rw & (1 << (flag)))
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/*
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* Old defines, these should eventually be replaced by direct usage of
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* bio_rw_flagged()
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*/
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#define bio_barrier(bio) bio_rw_flagged(bio, BIO_RW_BARRIER)
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#define bio_sync(bio) bio_rw_flagged(bio, BIO_RW_SYNCIO)
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#define bio_unplug(bio) bio_rw_flagged(bio, BIO_RW_UNPLUG)
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#define bio_failfast_dev(bio) bio_rw_flagged(bio, BIO_RW_FAILFAST_DEV)
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#define bio_failfast_transport(bio) \
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bio_rw_flagged(bio, BIO_RW_FAILFAST_TRANSPORT)
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#define bio_failfast_driver(bio) \
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bio_rw_flagged(bio, BIO_RW_FAILFAST_DRIVER)
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#define bio_rw_ahead(bio) bio_rw_flagged(bio, BIO_RW_AHEAD)
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#define bio_rw_meta(bio) bio_rw_flagged(bio, BIO_RW_META)
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#define bio_discard(bio) bio_rw_flagged(bio, BIO_RW_DISCARD)
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#define bio_noidle(bio) bio_rw_flagged(bio, BIO_RW_NOIDLE)
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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 bio_iovec_idx(bio, idx) (&((bio)->bi_io_vec[(idx)]))
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#define bio_iovec(bio) bio_iovec_idx((bio), (bio)->bi_idx)
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#define bio_page(bio) bio_iovec((bio))->bv_page
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#define bio_offset(bio) bio_iovec((bio))->bv_offset
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#define bio_segments(bio) ((bio)->bi_vcnt - (bio)->bi_idx)
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#define bio_sectors(bio) ((bio)->bi_size >> 9)
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#define bio_empty_barrier(bio) (bio_barrier(bio) && !bio_has_data(bio) && !bio_discard(bio))
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static inline unsigned int bio_cur_bytes(struct bio *bio)
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{
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if (bio->bi_vcnt)
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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_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->bi_vcnt)
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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 int bio_has_allocated_vec(struct bio *bio)
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{
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return bio->bi_io_vec && bio->bi_io_vec != bio->bi_inline_vecs;
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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, idx, kmtype) \
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(kmap_atomic(bio_iovec_idx((bio), (idx))->bv_page, kmtype) + \
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bio_iovec_idx((bio), (idx))->bv_offset)
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#define __bio_kunmap_atomic(addr, kmtype) kunmap_atomic(addr, kmtype)
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/*
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* merge helpers etc
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*/
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#define __BVEC_END(bio) bio_iovec_idx((bio), (bio)->bi_vcnt - 1)
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#define __BVEC_START(bio) bio_iovec_idx((bio), (bio)->bi_idx)
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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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#define BIO_SEG_BOUNDARY(q, b1, b2) \
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BIOVEC_SEG_BOUNDARY((q), __BVEC_END((b1)), __BVEC_START((b2)))
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#define bio_io_error(bio) bio_endio((bio), -EIO)
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/*
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* drivers should not use the __ version unless they _really_ want to
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* run through the entire bio and not just pending pieces
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*/
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#define __bio_for_each_segment(bvl, bio, i, start_idx) \
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for (bvl = bio_iovec_idx((bio), (start_idx)), i = (start_idx); \
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i < (bio)->bi_vcnt; \
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bvl++, i++)
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#define bio_for_each_segment(bvl, bio, i) \
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__bio_for_each_segment(bvl, bio, i, (bio)->bi_idx)
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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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#if defined(CONFIG_BLK_DEV_INTEGRITY)
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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 bio_vec *bip_vec; /* integrity data vector */
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sector_t bip_sector; /* virtual start sector */
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void *bip_buf; /* generated integrity data */
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bio_end_io_t *bip_end_io; /* saved I/O completion fn */
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unsigned int bip_size;
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unsigned short bip_pool; /* pool the ivec came from */
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unsigned short bip_vcnt; /* # of integrity bio_vecs */
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unsigned short bip_idx; /* current bip_vec index */
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struct work_struct bip_work; /* I/O completion */
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};
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#endif /* CONFIG_BLK_DEV_INTEGRITY */
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/*
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* A bio_pair is used when we need to split a bio.
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* This can only happen for a bio that refers to just one
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* page of data, and in the unusual situation when the
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* page crosses a chunk/device boundary
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*
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* The address of the master bio is stored in bio1.bi_private
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* The address of the pool the pair was allocated from is stored
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* in bio2.bi_private
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*/
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struct bio_pair {
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struct bio bio1, bio2;
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struct bio_vec bv1, bv2;
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#if defined(CONFIG_BLK_DEV_INTEGRITY)
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struct bio_integrity_payload bip1, bip2;
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struct bio_vec iv1, iv2;
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#endif
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atomic_t cnt;
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int error;
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};
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extern struct bio_pair *bio_split(struct bio *bi, int first_sectors);
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extern void bio_pair_release(struct bio_pair *dbio);
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extern struct bio_set *bioset_create(unsigned int, unsigned int);
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extern void bioset_free(struct bio_set *);
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extern struct bio *bio_alloc(gfp_t, int);
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extern struct bio *bio_kmalloc(gfp_t, int);
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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_free(struct bio *, struct bio_set *);
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extern void bio_endio(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 void __bio_clone(struct bio *, struct bio *);
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extern struct bio *bio_clone(struct bio *, gfp_t);
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extern void bio_init(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 sector_t bio_sector_offset(struct bio *, unsigned short, unsigned int);
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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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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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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 *, 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_bs(gfp_t, int, unsigned long *, struct bio_set *);
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extern void bvec_free_bs(struct bio_set *, struct bio_vec *, unsigned int);
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extern unsigned int bvec_nr_vecs(unsigned short idx);
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/*
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* Allow queuer to specify a completion CPU for this bio
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*/
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static inline void bio_set_completion_cpu(struct bio *bio, unsigned int cpu)
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{
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bio->bi_comp_cpu = cpu;
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}
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/*
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* bio_set is used to allow other portions of the IO system to
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* allocate their own private memory pools for bio and iovec structures.
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* These memory pools in turn all allocate from the bio_slab
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* and the bvec_slabs[].
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*/
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#define BIO_POOL_SIZE 2
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#define BIOVEC_NR_POOLS 6
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#define BIOVEC_MAX_IDX (BIOVEC_NR_POOLS - 1)
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struct bio_set {
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struct kmem_cache *bio_slab;
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unsigned int front_pad;
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mempool_t *bio_pool;
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mempool_t *bvec_pool;
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};
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struct biovec_slab {
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int nr_vecs;
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char *name;
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struct kmem_cache *slab;
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};
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extern struct bio_set *fs_bio_set;
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extern struct biovec_slab bvec_slabs[BIOVEC_NR_POOLS] __read_mostly;
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/*
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* a small number of entries is fine, not going to be performance critical.
|
|
* basically we just need to survive
|
|
*/
|
|
#define BIO_SPLIT_ENTRIES 2
|
|
|
|
#ifdef CONFIG_HIGHMEM
|
|
/*
|
|
* remember never ever reenable interrupts between a bvec_kmap_irq and
|
|
* bvec_kunmap_irq!
|
|
*
|
|
* This function MUST be inlined - it plays with the CPU interrupt flags.
|
|
*/
|
|
static __always_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, KM_BIO_SRC_IRQ);
|
|
|
|
BUG_ON(addr & ~PAGE_MASK);
|
|
|
|
return (char *) addr + bvec->bv_offset;
|
|
}
|
|
|
|
static __always_inline void bvec_kunmap_irq(char *buffer,
|
|
unsigned long *flags)
|
|
{
|
|
unsigned long ptr = (unsigned long) buffer & PAGE_MASK;
|
|
|
|
kunmap_atomic((void *) ptr, KM_BIO_SRC_IRQ);
|
|
local_irq_restore(*flags);
|
|
}
|
|
|
|
#else
|
|
#define bvec_kmap_irq(bvec, flags) (page_address((bvec)->bv_page) + (bvec)->bv_offset)
|
|
#define bvec_kunmap_irq(buf, flags) do { *(flags) = 0; } while (0)
|
|
#endif
|
|
|
|
static inline char *__bio_kmap_irq(struct bio *bio, unsigned short idx,
|
|
unsigned long *flags)
|
|
{
|
|
return bvec_kmap_irq(bio_iovec_idx(bio, idx), flags);
|
|
}
|
|
#define __bio_kunmap_irq(buf, flags) bvec_kunmap_irq(buf, flags)
|
|
|
|
#define bio_kmap_irq(bio, flags) \
|
|
__bio_kmap_irq((bio), (bio)->bi_idx, (flags))
|
|
#define bio_kunmap_irq(buf,flags) __bio_kunmap_irq(buf, flags)
|
|
|
|
/*
|
|
* Check whether this bio carries any data or not. A NULL bio is allowed.
|
|
*/
|
|
static inline int bio_has_data(struct bio *bio)
|
|
{
|
|
return bio && bio->bi_io_vec != NULL;
|
|
}
|
|
|
|
/*
|
|
* 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_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;
|
|
}
|
|
|
|
#if defined(CONFIG_BLK_DEV_INTEGRITY)
|
|
|
|
#define bip_vec_idx(bip, idx) (&(bip->bip_vec[(idx)]))
|
|
#define bip_vec(bip) bip_vec_idx(bip, 0)
|
|
|
|
#define __bip_for_each_vec(bvl, bip, i, start_idx) \
|
|
for (bvl = bip_vec_idx((bip), (start_idx)), i = (start_idx); \
|
|
i < (bip)->bip_vcnt; \
|
|
bvl++, i++)
|
|
|
|
#define bip_for_each_vec(bvl, bip, i) \
|
|
__bip_for_each_vec(bvl, bip, i, (bip)->bip_idx)
|
|
|
|
#define bio_integrity(bio) (bio->bi_integrity != NULL)
|
|
|
|
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 int bio_integrity_enabled(struct bio *bio);
|
|
extern int bio_integrity_set_tag(struct bio *, void *, unsigned int);
|
|
extern int bio_integrity_get_tag(struct bio *, void *, unsigned int);
|
|
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 void bio_integrity_split(struct bio *, struct bio_pair *, int);
|
|
extern int bio_integrity_clone(struct bio *, struct bio *, gfp_t);
|
|
|
|
#else /* CONFIG_BLK_DEV_INTEGRITY */
|
|
|
|
#define bio_integrity(a) (0)
|
|
#define bio_integrity_prep(a) (0)
|
|
#define bio_integrity_enabled(a) (0)
|
|
#define bio_integrity_clone(a, b, c) (0)
|
|
#define bio_integrity_free(a) do { } while (0)
|
|
#define bio_integrity_endio(a, b) do { } while (0)
|
|
#define bio_integrity_advance(a, b) do { } while (0)
|
|
#define bio_integrity_trim(a, b, c) do { } while (0)
|
|
#define bio_integrity_split(a, b, c) do { } while (0)
|
|
#define bio_integrity_set_tag(a, b, c) do { } while (0)
|
|
#define bio_integrity_get_tag(a, b, c) do { } while (0)
|
|
|
|
#endif /* CONFIG_BLK_DEV_INTEGRITY */
|
|
|
|
#endif /* CONFIG_BLOCK */
|
|
#endif /* __LINUX_BIO_H */
|