4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
23 * Copyright (C) 2011 Lawrence Livermore National Security, LLC.
24 * Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER).
25 * Written by Brian Behlendorf <behlendorf1@llnl.gov>.
32 #include <linux/blkdev.h>
33 #include <linux/elevator.h>
36 typedef unsigned __bitwise__ fmode_t;
37 #endif /* HAVE_FMODE_T */
39 #ifndef HAVE_BLK_FETCH_REQUEST
40 static inline struct request *
41 blk_fetch_request(struct request_queue *q)
45 req = elv_next_request(q);
47 blkdev_dequeue_request(req);
51 #endif /* HAVE_BLK_FETCH_REQUEST */
53 #ifndef HAVE_BLK_REQUEUE_REQUEST
55 blk_requeue_request(request_queue_t *q, struct request *req)
57 elv_requeue_request(q, req);
59 #endif /* HAVE_BLK_REQUEUE_REQUEST */
61 #ifndef HAVE_BLK_END_REQUEST
63 __blk_end_request(struct request *req, int error, unsigned int nr_bytes)
68 * Request has already been dequeued but 2.6.18 version of
69 * end_request() unconditionally dequeues the request so we
70 * add it to a local list to prevent hitting the BUG_ON.
72 list_add(&req->queuelist, &list);
75 * The old API required the driver to end each segment and not
76 * the entire request. In our case we always need to end the
77 * entire request partial requests are not supported.
79 req->hard_cur_sectors = nr_bytes >> 9;
80 end_request(req, ((error == 0) ? 1 : error));
86 blk_end_request(struct request *req, int error, unsigned int nr_bytes)
88 struct request_queue *q = req->q;
91 spin_lock_irq(q->queue_lock);
92 rc = __blk_end_request(req, error, nr_bytes);
93 spin_unlock_irq(q->queue_lock);
98 # ifdef HAVE_BLK_END_REQUEST_GPL_ONLY
100 * Define required to avoid conflicting 2.6.29 non-static prototype for a
101 * GPL-only version of the helper. As of 2.6.31 the helper is available
102 * to non-GPL modules and is not explicitly exported GPL-only.
104 # define __blk_end_request __blk_end_request_x
105 # define blk_end_request blk_end_request_x
108 __blk_end_request_x(struct request *req, int error, unsigned int nr_bytes)
111 * The old API required the driver to end each segment and not
112 * the entire request. In our case we always need to end the
113 * entire request partial requests are not supported.
115 req->hard_cur_sectors = nr_bytes >> 9;
116 end_request(req, ((error == 0) ? 1 : error));
121 blk_end_request_x(struct request *req, int error, unsigned int nr_bytes)
123 struct request_queue *q = req->q;
126 spin_lock_irq(q->queue_lock);
127 rc = __blk_end_request_x(req, error, nr_bytes);
128 spin_unlock_irq(q->queue_lock);
132 # endif /* HAVE_BLK_END_REQUEST_GPL_ONLY */
133 #endif /* HAVE_BLK_END_REQUEST */
135 #ifndef HAVE_BLK_RQ_POS
136 static inline sector_t
137 blk_rq_pos(struct request *req)
141 #endif /* HAVE_BLK_RQ_POS */
143 #ifndef HAVE_BLK_RQ_SECTORS
144 static inline unsigned int
145 blk_rq_sectors(struct request *req)
147 return req->nr_sectors;
149 #endif /* HAVE_BLK_RQ_SECTORS */
151 #if !defined(HAVE_BLK_RQ_BYTES) || defined(HAVE_BLK_RQ_BYTES_GPL_ONLY)
153 * Define required to avoid conflicting 2.6.29 non-static prototype for a
154 * GPL-only version of the helper. As of 2.6.31 the helper is available
155 * to non-GPL modules in the form of a static inline in the header.
157 #define blk_rq_bytes __blk_rq_bytes
158 static inline unsigned int
159 __blk_rq_bytes(struct request *req)
161 return blk_rq_sectors(req) << 9;
163 #endif /* !HAVE_BLK_RQ_BYTES || HAVE_BLK_RQ_BYTES_GPL_ONLY */
166 * Most of the blk_* macros were removed in 2.6.36. Ostensibly this was
167 * done to improve readability and allow easier grepping. However, from
168 * a portability stand point the macros are helpful. Therefore the needed
169 * macros are redefined here if they are missing from the kernel.
171 #ifndef blk_fs_request
172 #define blk_fs_request(rq) ((rq)->cmd_type == REQ_TYPE_FS)
177 * The blk_queue_stackable() queue flag was added in 2.6.27 to handle dm
178 * stacking drivers. Prior to this request stacking drivers were detected
179 * by checking (q->request_fn == NULL), for earlier kernels we revert to
180 * this legacy behavior.
182 #ifndef blk_queue_stackable
183 #define blk_queue_stackable(q) ((q)->request_fn == NULL)
186 #ifndef HAVE_GET_DISK_RO
188 get_disk_ro(struct gendisk *disk)
193 policy = disk->part[0]->policy;
197 #endif /* HAVE_GET_DISK_RO */
199 #ifndef HAVE_RQ_IS_SYNC
201 rq_is_sync(struct request *req)
203 return (req->flags & REQ_RW_SYNC);
205 #endif /* HAVE_RQ_IS_SYNC */
207 #ifndef HAVE_RQ_FOR_EACH_SEGMENT
208 struct req_iterator {
213 # define for_each_bio(_bio) \
214 for (; _bio; _bio = _bio->bi_next)
216 # define __rq_for_each_bio(_bio, rq) \
218 for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)
220 # define rq_for_each_segment(bvl, _rq, _iter) \
221 __rq_for_each_bio(_iter.bio, _rq) \
222 bio_for_each_segment(bvl, _iter.bio, _iter.i)
223 #endif /* HAVE_RQ_FOR_EACH_SEGMENT */
226 * Portable helper for correctly setting the FAILFAST flags. The
227 * correct usage has changed 3 times from 2.6.12 to 2.6.38.
230 bio_set_flags_failfast(struct block_device *bdev, int *flags)
234 * Disable FAILFAST for loopback devices because of the
235 * following incorrect BUG_ON() in loop_make_request().
236 * This support is also disabled for md devices because the
237 * test suite layers md devices on top of loopback devices.
238 * This may be removed when the loopback driver is fixed.
240 * BUG_ON(!lo || (rw != READ && rw != WRITE));
242 if ((MAJOR(bdev->bd_dev) == LOOP_MAJOR) ||
243 (MAJOR(bdev->bd_dev) == MD_MAJOR))
246 #ifdef BLOCK_EXT_MAJOR
247 if (MAJOR(bdev->bd_dev) == BLOCK_EXT_MAJOR)
249 #endif /* BLOCK_EXT_MAJOR */
250 #endif /* CONFIG_BUG */
252 #ifdef HAVE_BIO_RW_FAILFAST_DTD
253 /* BIO_RW_FAILFAST_* preferred interface from 2.6.28 - 2.6.35 */
255 ((1 << BIO_RW_FAILFAST_DEV) |
256 (1 << BIO_RW_FAILFAST_TRANSPORT) |
257 (1 << BIO_RW_FAILFAST_DRIVER));
259 # ifdef HAVE_BIO_RW_FAILFAST
260 /* BIO_RW_FAILFAST preferred interface from 2.6.12 - 2.6.27 */
261 *flags |= (1 << BIO_RW_FAILFAST);
263 # ifdef HAVE_REQ_FAILFAST_MASK
264 /* REQ_FAILFAST_* preferred interface from 2.6.36 - 2.6.xx,
265 * the BIO_* and REQ_* flags were unified under REQ_* flags. */
266 *flags |= REQ_FAILFAST_MASK;
267 # endif /* HAVE_REQ_FAILFAST_MASK */
268 # endif /* HAVE_BIO_RW_FAILFAST */
269 #endif /* HAVE_BIO_RW_FAILFAST_DTD */
273 * Maximum disk label length, it may be undefined for some kernels.
275 #ifndef DISK_NAME_LEN
276 #define DISK_NAME_LEN 32
277 #endif /* DISK_NAME_LEN */
281 * The bio_end_io() prototype changed slightly. These are helper
282 * macro's to ensure the prototype and return value are handled.
284 #ifdef HAVE_2ARGS_BIO_END_IO_T
285 # define BIO_END_IO_PROTO(fn, x, y, z) static void fn(struct bio *x, int z)
286 # define BIO_END_IO_RETURN(rc) return
288 # define BIO_END_IO_PROTO(fn, x, y, z) static int fn(struct bio *x, \
289 unsigned int y, int z)
290 # define BIO_END_IO_RETURN(rc) return rc
291 #endif /* HAVE_2ARGS_BIO_END_IO_T */
294 * 2.6.38 - 2.6.x API,
295 * blkdev_get_by_path()
298 * 2.6.28 - 2.6.37 API,
299 * open_bdev_exclusive()
300 * close_bdev_exclusive()
302 * 2.6.12 - 2.6.27 API,
306 * Used to exclusively open a block device from within the kernel.
308 #if defined(HAVE_BLKDEV_GET_BY_PATH)
309 # define vdev_bdev_open(path, md, hld) blkdev_get_by_path(path, \
310 (md) | FMODE_EXCL, hld)
311 # define vdev_bdev_close(bdev, md) blkdev_put(bdev, (md) | FMODE_EXCL)
312 #elif defined(HAVE_OPEN_BDEV_EXCLUSIVE)
313 # define vdev_bdev_open(path, md, hld) open_bdev_exclusive(path, md, hld)
314 # define vdev_bdev_close(bdev, md) close_bdev_exclusive(bdev, md)
316 # define vdev_bdev_open(path, md, hld) open_bdev_excl(path, md, hld)
317 # define vdev_bdev_close(bdev, md) close_bdev_excl(bdev)
318 #endif /* HAVE_BLKDEV_GET_BY_PATH | HAVE_OPEN_BDEV_EXCLUSIVE */
322 * The function invalidate_bdev() lost it's second argument because
325 #ifdef HAVE_1ARG_INVALIDATE_BDEV
326 # define vdev_bdev_invalidate(bdev) invalidate_bdev(bdev)
328 # define vdev_bdev_invalidate(bdev) invalidate_bdev(bdev, 1)
329 #endif /* HAVE_1ARG_INVALIDATE_BDEV */
333 * Change to make it explicit there this is the logical block size.
335 #ifdef HAVE_BDEV_LOGICAL_BLOCK_SIZE
336 # define vdev_bdev_block_size(bdev) bdev_logical_block_size(bdev)
338 # define vdev_bdev_block_size(bdev) bdev_hardsect_size(bdev)
342 * Default Linux IO Scheduler,
343 * Setting the scheduler to noop will allow the Linux IO scheduler to
344 * still perform front and back merging, while leaving the request
345 * ordering and prioritization to the ZFS IO scheduler.
347 #define VDEV_SCHEDULER "noop"
349 #endif /* _ZFS_BLKDEV_H */