zfs/include/sys/blkdev.h

265 lines
7.0 KiB
C

/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright (C) 2008-2010 Lawrence Livermore National Security, LLC.
* Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER).
* Written by Brian Behlendorf <behlendorf1@llnl.gov>.
* LLNL-CODE-403049.
*/
#ifndef _SYS_BLKDEV_H
#define _SYS_BLKDEV_H
#ifdef _KERNEL
#include <linux/blkdev.h>
#include <linux/elevator.h>
#ifndef HAVE_FMODE_T
typedef unsigned __bitwise__ fmode_t;
#endif /* HAVE_FMODE_T */
#ifndef HAVE_BLK_FETCH_REQUEST
static inline struct request *
blk_fetch_request(struct request_queue *q)
{
struct request *req;
req = elv_next_request(q);
if (req)
blkdev_dequeue_request(req);
return req;
}
#endif /* HAVE_BLK_FETCH_REQUEST */
#ifndef HAVE_BLK_REQUEUE_REQUEST
static inline void
blk_requeue_request(request_queue_t *q, struct request *req)
{
elv_requeue_request(q, req);
}
#endif /* HAVE_BLK_REQUEUE_REQUEST */
#ifndef HAVE_BLK_END_REQUEST
static inline bool
__blk_end_request(struct request *req, int error, unsigned int nr_bytes)
{
LIST_HEAD(list);
/*
* Request has already been dequeued but 2.6.18 version of
* end_request() unconditionally dequeues the request so we
* add it to a local list to prevent hitting the BUG_ON.
*/
list_add(&req->queuelist, &list);
/*
* The old API required the driver to end each segment and not
* the entire request. In our case we always need to end the
* entire request partial requests are not supported.
*/
req->hard_cur_sectors = nr_bytes >> 9;
end_request(req, ((error == 0) ? 1 : error));
return 0;
}
static inline bool
blk_end_request(struct request *req, int error, unsigned int nr_bytes)
{
struct request_queue *q = req->q;
bool rc;
spin_lock_irq(q->queue_lock);
rc = __blk_end_request(req, error, nr_bytes);
spin_unlock_irq(q->queue_lock);
return rc;
}
#else
# ifdef HAVE_BLK_END_REQUEST_GPL_ONLY
/*
* Define required to avoid conflicting 2.6.29 non-static prototype for a
* GPL-only version of the helper. As of 2.6.31 the helper is available
* to non-GPL modules and is not explicitly exported GPL-only.
*/
# define __blk_end_request __blk_end_request_x
# define blk_end_request blk_end_request_x
static inline bool
__blk_end_request_x(struct request *req, int error, unsigned int nr_bytes)
{
/*
* The old API required the driver to end each segment and not
* the entire request. In our case we always need to end the
* entire request partial requests are not supported.
*/
req->hard_cur_sectors = nr_bytes >> 9;
end_request(req, ((error == 0) ? 1 : error));
return 0;
}
static inline bool
blk_end_request_x(struct request *req, int error, unsigned int nr_bytes)
{
struct request_queue *q = req->q;
bool rc;
spin_lock_irq(q->queue_lock);
rc = __blk_end_request_x(req, error, nr_bytes);
spin_unlock_irq(q->queue_lock);
return rc;
}
# endif /* HAVE_BLK_END_REQUEST_GPL_ONLY */
#endif /* HAVE_BLK_END_REQUEST */
#ifndef HAVE_BLK_RQ_POS
static inline sector_t
blk_rq_pos(struct request *req)
{
return req->sector;
}
#endif /* HAVE_BLK_RQ_POS */
#ifndef HAVE_BLK_RQ_SECTORS
static inline unsigned int
blk_rq_sectors(struct request *req)
{
return req->nr_sectors;
}
#endif /* HAVE_BLK_RQ_SECTORS */
#if !defined(HAVE_BLK_RQ_BYTES) || defined(HAVE_BLK_RQ_BYTES_GPL_ONLY)
/*
* Define required to avoid conflicting 2.6.29 non-static prototype for a
* GPL-only version of the helper. As of 2.6.31 the helper is available
* to non-GPL modules in the form of a static inline in the header.
*/
#define blk_rq_bytes __blk_rq_bytes
static inline unsigned int
__blk_rq_bytes(struct request *req)
{
return blk_rq_sectors(req) << 9;
}
#endif /* !HAVE_BLK_RQ_BYTES || HAVE_BLK_RQ_BYTES_GPL_ONLY */
/*
* Most of the blk_* macros were removed in 2.6.36. Ostensibly this was
* done to improve readability and allow easier grepping. However, from
* a portability stand point the macros are helpful. Therefore the needed
* macros are redefined here if they are missing from the kernel.
*/
#ifndef blk_fs_request
#define blk_fs_request(rq) ((rq)->cmd_type == REQ_TYPE_FS)
#endif
#ifndef HAVE_GET_DISK_RO
static inline int
get_disk_ro(struct gendisk *disk)
{
int policy = 0;
if (disk->part[0])
policy = disk->part[0]->policy;
return policy;
}
#endif /* HAVE_GET_DISK_RO */
#ifndef HAVE_RQ_IS_SYNC
static inline bool
rq_is_sync(struct request *req)
{
return (req->flags & REQ_RW_SYNC);
}
#endif /* HAVE_RQ_IS_SYNC */
#ifndef HAVE_RQ_FOR_EACH_SEGMENT
struct req_iterator {
int i;
struct bio *bio;
};
# define for_each_bio(_bio) \
for (; _bio; _bio = _bio->bi_next)
# define __rq_for_each_bio(_bio, rq) \
if ((rq->bio)) \
for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)
# define rq_for_each_segment(bvl, _rq, _iter) \
__rq_for_each_bio(_iter.bio, _rq) \
bio_for_each_segment(bvl, _iter.bio, _iter.i)
#endif /* HAVE_RQ_FOR_EACH_SEGMENT */
static inline void
bio_set_flags_failfast(struct block_device *bdev, int *flags)
{
#ifdef CONFIG_BUG
/*
* Disable FAILFAST for loopback devices because of the
* following incorrect BUG_ON() in loop_make_request().
* This support is also disabled for md devices because the
* test suite layers md devices on top of loopback devices.
* This may be removed when the loopback driver is fixed.
*
* BUG_ON(!lo || (rw != READ && rw != WRITE));
*/
if ((MAJOR(bdev->bd_dev) == LOOP_MAJOR) ||
(MAJOR(bdev->bd_dev) == MD_MAJOR))
return;
#ifdef BLOCK_EXT_MAJOR
if (MAJOR(bdev->bd_dev) == BLOCK_EXT_MAJOR)
return;
#endif /* BLOCK_EXT_MAJOR */
#endif /* CONFIG_BUG */
#ifdef HAVE_BIO_RW_FAILFAST_DTD
/* BIO_RW_FAILFAST_* preferred interface from 2.6.28 - 2.6.35 */
*flags |=
((1 << BIO_RW_FAILFAST_DEV) |
(1 << BIO_RW_FAILFAST_TRANSPORT) |
(1 << BIO_RW_FAILFAST_DRIVER));
#else
# ifdef HAVE_BIO_RW_FAILFAST
/* BIO_RW_FAILFAST preferred interface from 2.6.12 - 2.6.27 */
*flags |= (1 << BIO_RW_FAILFAST);
# else
# ifdef HAVE_REQ_FAILFAST_MASK
/* REQ_FAILFAST_* preferred interface from 2.6.36 - 2.6.xx,
* the BIO_* and REQ_* flags were unified under REQ_* flags. */
*flags |= REQ_FAILFAST_MASK;
# endif /* HAVE_REQ_FAILFAST_MASK */
# endif /* HAVE_BIO_RW_FAILFAST */
#endif /* HAVE_BIO_RW_FAILFAST_DTD */
}
#ifndef DISK_NAME_LEN
#define DISK_NAME_LEN 32
#endif /* DISK_NAME_LEN */
#endif /* KERNEL */
#endif /* _SYS_BLKDEV_H */