a971acbc25
Allow one to implement a 'car limit' for bioq_disksort. debug.bioq_batchsize sets the size of car limit. Every time we queue that many requests, we start over so that we limit the latency for requests when the software queue depths are large. A value of '0', the default, means to revert to the old behavior. Sponsored by: Netflix
185 lines
6.6 KiB
C
185 lines
6.6 KiB
C
/*-
|
|
* SPDX-License-Identifier: BSD-3-Clause
|
|
*
|
|
* Copyright (c) 1982, 1986, 1989, 1993
|
|
* The Regents of the University of California. All rights reserved.
|
|
* (c) UNIX System Laboratories, Inc.
|
|
* All or some portions of this file are derived from material licensed
|
|
* to the University of California by American Telephone and Telegraph
|
|
* Co. or Unix System Laboratories, Inc. and are reproduced herein with
|
|
* the permission of UNIX System Laboratories, Inc.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
* 3. Neither the name of the University nor the names of its contributors
|
|
* may be used to endorse or promote products derived from this software
|
|
* without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*
|
|
* @(#)buf.h 8.9 (Berkeley) 3/30/95
|
|
* $FreeBSD$
|
|
*/
|
|
|
|
#ifndef _SYS_BIO_H_
|
|
#define _SYS_BIO_H_
|
|
|
|
#include <sys/queue.h>
|
|
#include <sys/disk_zone.h>
|
|
|
|
/* bio_cmd */
|
|
#define BIO_READ 0x01 /* Read I/O data */
|
|
#define BIO_WRITE 0x02 /* Write I/O data */
|
|
#define BIO_DELETE 0x03 /* TRIM or free blocks, i.e. mark as unused */
|
|
#define BIO_GETATTR 0x04 /* Get GEOM attributes of object */
|
|
#define BIO_FLUSH 0x05 /* Commit outstanding I/O now */
|
|
#define BIO_CMD0 0x06 /* Available for local hacks */
|
|
#define BIO_CMD1 0x07 /* Available for local hacks */
|
|
#define BIO_CMD2 0x08 /* Available for local hacks */
|
|
#define BIO_ZONE 0x09 /* Zone command */
|
|
|
|
/* bio_flags */
|
|
#define BIO_ERROR 0x01 /* An error occurred processing this bio. */
|
|
#define BIO_DONE 0x02 /* This bio is finished. */
|
|
#define BIO_ONQUEUE 0x04 /* This bio is in a queue & not yet taken. */
|
|
/*
|
|
* This bio must be executed after all previous bios in the queue have been
|
|
* executed, and before any successive bios can be executed.
|
|
*/
|
|
#define BIO_ORDERED 0x08
|
|
#define BIO_UNMAPPED 0x10
|
|
#define BIO_TRANSIENT_MAPPING 0x20
|
|
#define BIO_VLIST 0x40
|
|
|
|
#ifdef _KERNEL
|
|
struct disk;
|
|
struct bio;
|
|
struct vm_map;
|
|
|
|
/* Empty classifier tag, to prevent further classification. */
|
|
#define BIO_NOTCLASSIFIED (void *)(~0UL)
|
|
|
|
typedef void bio_task_t(void *);
|
|
|
|
/*
|
|
* The bio structure describes an I/O operation in the kernel.
|
|
*/
|
|
struct bio {
|
|
uint16_t bio_cmd; /* I/O operation. */
|
|
uint16_t bio_flags; /* General flags. */
|
|
uint16_t bio_cflags; /* Private use by the consumer. */
|
|
uint16_t bio_pflags; /* Private use by the provider. */
|
|
struct cdev *bio_dev; /* Device to do I/O on. */
|
|
struct disk *bio_disk; /* Valid below geom_disk.c only */
|
|
off_t bio_offset; /* Offset into file. */
|
|
long bio_bcount; /* Valid bytes in buffer. */
|
|
caddr_t bio_data; /* Memory, superblocks, indirect etc. */
|
|
struct vm_page **bio_ma; /* Or unmapped. */
|
|
int bio_ma_offset; /* Offset in the first page of bio_ma. */
|
|
int bio_ma_n; /* Number of pages in bio_ma. */
|
|
int bio_error; /* Errno for BIO_ERROR. */
|
|
long bio_resid; /* Remaining I/O in bytes. */
|
|
void (*bio_done)(struct bio *);
|
|
void *bio_driver1; /* Private use by the provider. */
|
|
void *bio_driver2; /* Private use by the provider. */
|
|
void *bio_caller1; /* Private use by the consumer. */
|
|
void *bio_caller2; /* Private use by the consumer. */
|
|
TAILQ_ENTRY(bio) bio_queue; /* Disksort queue. */
|
|
const char *bio_attribute; /* Attribute for BIO_[GS]ETATTR */
|
|
struct disk_zone_args bio_zone;/* Used for BIO_ZONE */
|
|
struct g_consumer *bio_from; /* GEOM linkage */
|
|
struct g_provider *bio_to; /* GEOM linkage */
|
|
off_t bio_length; /* Like bio_bcount */
|
|
off_t bio_completed; /* Inverse of bio_resid */
|
|
u_int bio_children; /* Number of spawned bios */
|
|
u_int bio_inbed; /* Children safely home by now */
|
|
struct bio *bio_parent; /* Pointer to parent */
|
|
struct bintime bio_t0; /* Time request started */
|
|
|
|
bio_task_t *bio_task; /* Task_queue handler */
|
|
void *bio_task_arg; /* Argument to above */
|
|
|
|
void *bio_classifier1; /* Classifier tag. */
|
|
void *bio_classifier2; /* Classifier tag. */
|
|
|
|
#ifdef DIAGNOSTIC
|
|
void *_bio_caller1;
|
|
void *_bio_caller2;
|
|
uint8_t _bio_cflags;
|
|
#endif
|
|
#if defined(BUF_TRACKING) || defined(FULL_BUF_TRACKING)
|
|
struct buf *bio_track_bp; /* Parent buf for tracking */
|
|
#endif
|
|
|
|
/* XXX: these go away when bio chaining is introduced */
|
|
daddr_t bio_pblkno; /* physical block number */
|
|
};
|
|
|
|
struct uio;
|
|
struct devstat;
|
|
|
|
struct bio_queue_head {
|
|
TAILQ_HEAD(bio_queue, bio) queue;
|
|
off_t last_offset;
|
|
struct bio *insert_point;
|
|
int total;
|
|
int batched;
|
|
};
|
|
|
|
extern struct vm_map *bio_transient_map;
|
|
extern int bio_transient_maxcnt;
|
|
|
|
void biodone(struct bio *bp);
|
|
void biofinish(struct bio *bp, struct devstat *stat, int error);
|
|
int biowait(struct bio *bp, const char *wchan);
|
|
|
|
#if defined(BUF_TRACKING) || defined(FULL_BUF_TRACKING)
|
|
void biotrack_buf(struct bio *bp, const char *location);
|
|
|
|
static __inline void
|
|
biotrack(struct bio *bp, const char *location)
|
|
{
|
|
|
|
if (bp->bio_track_bp != NULL)
|
|
biotrack_buf(bp, location);
|
|
}
|
|
#else
|
|
static __inline void
|
|
biotrack(struct bio *bp __unused, const char *location __unused)
|
|
{
|
|
}
|
|
#endif
|
|
|
|
void bioq_disksort(struct bio_queue_head *ap, struct bio *bp);
|
|
struct bio *bioq_first(struct bio_queue_head *head);
|
|
struct bio *bioq_takefirst(struct bio_queue_head *head);
|
|
void bioq_flush(struct bio_queue_head *head, struct devstat *stp, int error);
|
|
void bioq_init(struct bio_queue_head *head);
|
|
void bioq_insert_head(struct bio_queue_head *head, struct bio *bp);
|
|
void bioq_insert_tail(struct bio_queue_head *head, struct bio *bp);
|
|
void bioq_remove(struct bio_queue_head *head, struct bio *bp);
|
|
|
|
int physio(struct cdev *dev, struct uio *uio, int ioflag);
|
|
#define physread physio
|
|
#define physwrite physio
|
|
|
|
#endif /* _KERNEL */
|
|
|
|
#endif /* !_SYS_BIO_H_ */
|