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]
22 * Copyright (C) 2008-2010 Lawrence Livermore National Security, LLC.
23 * Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER).
24 * Rewritten for Linux by Brian Behlendorf <behlendorf1@llnl.gov>.
26 * Copyright (c) 2012, 2019 by Delphix. All rights reserved.
29 #include <sys/zfs_context.h>
30 #include <sys/spa_impl.h>
31 #include <sys/vdev_disk.h>
32 #include <sys/vdev_impl.h>
33 #include <sys/vdev_trim.h>
35 #include <sys/fs/zfs.h>
37 #include <linux/blkpg.h>
38 #include <linux/msdos_fs.h>
39 #include <linux/vfs_compat.h>
41 typedef struct vdev_disk {
42 struct block_device *vd_bdev;
47 * Unique identifier for the exclusive vdev holder.
49 static void *zfs_vdev_holder = VDEV_HOLDER;
52 * Wait up to zfs_vdev_open_timeout_ms milliseconds before determining the
53 * device is missing. The missing path may be transient since the links
54 * can be briefly removed and recreated in response to udev events.
56 static unsigned zfs_vdev_open_timeout_ms = 1000;
59 * Size of the "reserved" partition, in blocks.
61 #define EFI_MIN_RESV_SIZE (16 * 1024)
64 * Virtual device vector for disks.
66 typedef struct dio_request {
67 zio_t *dr_zio; /* Parent ZIO */
68 atomic_t dr_ref; /* References */
69 int dr_error; /* Bio error */
70 int dr_bio_count; /* Count of bio's */
71 struct bio *dr_bio[0]; /* Attached bio's */
75 vdev_bdev_mode(spa_mode_t spa_mode)
79 if (spa_mode & SPA_MODE_READ)
82 if (spa_mode & SPA_MODE_WRITE)
89 * Returns the usable capacity (in bytes) for the partition or disk.
92 bdev_capacity(struct block_device *bdev)
94 return (i_size_read(bdev->bd_inode));
98 * Returns the maximum expansion capacity of the block device (in bytes).
100 * It is possible to expand a vdev when it has been created as a wholedisk
101 * and the containing block device has increased in capacity. Or when the
102 * partition containing the pool has been manually increased in size.
104 * This function is only responsible for calculating the potential expansion
105 * size so it can be reported by 'zpool list'. The efi_use_whole_disk() is
106 * responsible for verifying the expected partition layout in the wholedisk
107 * case, and updating the partition table if appropriate. Once the partition
108 * size has been increased the additional capacity will be visible using
111 * The returned maximum expansion capacity is always expected to be larger, or
112 * at the very least equal, to its usable capacity to prevent overestimating
113 * the pool expandsize.
116 bdev_max_capacity(struct block_device *bdev, uint64_t wholedisk)
121 if (wholedisk && bdev->bd_part != NULL && bdev != bdev->bd_contains) {
123 * When reporting maximum expansion capacity for a wholedisk
124 * deduct any capacity which is expected to be lost due to
125 * alignment restrictions. Over reporting this value isn't
126 * harmful and would only result in slightly less capacity
127 * than expected post expansion.
128 * The estimated available space may be slightly smaller than
129 * bdev_capacity() for devices where the number of sectors is
130 * not a multiple of the alignment size and the partition layout
131 * is keeping less than PARTITION_END_ALIGNMENT bytes after the
132 * "reserved" EFI partition: in such cases return the device
135 available = i_size_read(bdev->bd_contains->bd_inode) -
136 ((EFI_MIN_RESV_SIZE + NEW_START_BLOCK +
137 PARTITION_END_ALIGNMENT) << SECTOR_BITS);
138 psize = MAX(available, bdev_capacity(bdev));
140 psize = bdev_capacity(bdev);
147 vdev_disk_error(zio_t *zio)
150 * This function can be called in interrupt context, for instance while
151 * handling IRQs coming from a misbehaving disk device; use printk()
152 * which is safe from any context.
154 printk(KERN_WARNING "zio pool=%s vdev=%s error=%d type=%d "
155 "offset=%llu size=%llu flags=%x\n", spa_name(zio->io_spa),
156 zio->io_vd->vdev_path, zio->io_error, zio->io_type,
157 (u_longlong_t)zio->io_offset, (u_longlong_t)zio->io_size,
162 vdev_disk_open(vdev_t *v, uint64_t *psize, uint64_t *max_psize,
163 uint64_t *logical_ashift, uint64_t *physical_ashift)
165 struct block_device *bdev;
166 fmode_t mode = vdev_bdev_mode(spa_mode(v->vdev_spa));
167 hrtime_t timeout = MSEC2NSEC(zfs_vdev_open_timeout_ms);
170 /* Must have a pathname and it must be absolute. */
171 if (v->vdev_path == NULL || v->vdev_path[0] != '/') {
172 v->vdev_stat.vs_aux = VDEV_AUX_BAD_LABEL;
173 vdev_dbgmsg(v, "invalid vdev_path");
174 return (SET_ERROR(EINVAL));
178 * Reopen the device if it is currently open. When expanding a
179 * partition force re-scanning the partition table if userland
180 * did not take care of this already. We need to do this while closed
181 * in order to get an accurate updated block device size. Then
182 * since udev may need to recreate the device links increase the
183 * open retry timeout before reporting the device as unavailable.
187 char disk_name[BDEVNAME_SIZE + 6] = "/dev/";
188 boolean_t reread_part = B_FALSE;
190 rw_enter(&vd->vd_lock, RW_WRITER);
195 if (v->vdev_expanding && bdev != bdev->bd_contains) {
196 bdevname(bdev->bd_contains, disk_name + 5);
198 * If userland has BLKPG_RESIZE_PARTITION,
199 * then it should have updated the partition
200 * table already. We can detect this by
201 * comparing our current physical size
202 * with that of the device. If they are
203 * the same, then we must not have
204 * BLKPG_RESIZE_PARTITION or it failed to
205 * update the partition table online. We
206 * fallback to rescanning the partition
207 * table from the kernel below. However,
208 * if the capacity already reflects the
209 * updated partition, then we skip
210 * rescanning the partition table here.
212 if (v->vdev_psize == bdev_capacity(bdev))
213 reread_part = B_TRUE;
216 blkdev_put(bdev, mode | FMODE_EXCL);
220 bdev = blkdev_get_by_path(disk_name, mode | FMODE_EXCL,
223 int error = vdev_bdev_reread_part(bdev);
224 blkdev_put(bdev, mode | FMODE_EXCL);
227 zfs_vdev_open_timeout_ms * 2);
232 vd = kmem_zalloc(sizeof (vdev_disk_t), KM_SLEEP);
234 rw_init(&vd->vd_lock, NULL, RW_DEFAULT, NULL);
235 rw_enter(&vd->vd_lock, RW_WRITER);
239 * Devices are always opened by the path provided at configuration
240 * time. This means that if the provided path is a udev by-id path
241 * then drives may be re-cabled without an issue. If the provided
242 * path is a udev by-path path, then the physical location information
243 * will be preserved. This can be critical for more complicated
244 * configurations where drives are located in specific physical
245 * locations to maximize the systems tolerance to component failure.
247 * Alternatively, you can provide your own udev rule to flexibly map
248 * the drives as you see fit. It is not advised that you use the
249 * /dev/[hd]d devices which may be reordered due to probing order.
250 * Devices in the wrong locations will be detected by the higher
251 * level vdev validation.
253 * The specified paths may be briefly removed and recreated in
254 * response to udev events. This should be exceptionally unlikely
255 * because the zpool command makes every effort to verify these paths
256 * have already settled prior to reaching this point. Therefore,
257 * a ENOENT failure at this point is highly likely to be transient
258 * and it is reasonable to sleep and retry before giving up. In
259 * practice delays have been observed to be on the order of 100ms.
261 hrtime_t start = gethrtime();
262 bdev = ERR_PTR(-ENXIO);
263 while (IS_ERR(bdev) && ((gethrtime() - start) < timeout)) {
264 bdev = blkdev_get_by_path(v->vdev_path, mode | FMODE_EXCL,
266 if (unlikely(PTR_ERR(bdev) == -ENOENT)) {
267 schedule_timeout(MSEC_TO_TICK(10));
268 } else if (IS_ERR(bdev)) {
274 int error = -PTR_ERR(bdev);
275 vdev_dbgmsg(v, "open error=%d timeout=%llu/%llu", error,
276 (u_longlong_t)(gethrtime() - start),
277 (u_longlong_t)timeout);
280 rw_exit(&vd->vd_lock);
281 return (SET_ERROR(error));
285 rw_exit(&vd->vd_lock);
288 struct request_queue *q = bdev_get_queue(vd->vd_bdev);
290 /* Determine the physical block size */
291 int physical_block_size = bdev_physical_block_size(vd->vd_bdev);
293 /* Determine the logical block size */
294 int logical_block_size = bdev_logical_block_size(vd->vd_bdev);
296 /* Clear the nowritecache bit, causes vdev_reopen() to try again. */
297 v->vdev_nowritecache = B_FALSE;
299 /* Set when device reports it supports TRIM. */
300 v->vdev_has_trim = !!blk_queue_discard(q);
302 /* Set when device reports it supports secure TRIM. */
303 v->vdev_has_securetrim = !!blk_queue_discard_secure(q);
305 /* Inform the ZIO pipeline that we are non-rotational */
306 v->vdev_nonrot = blk_queue_nonrot(q);
308 /* Physical volume size in bytes for the partition */
309 *psize = bdev_capacity(vd->vd_bdev);
311 /* Physical volume size in bytes including possible expansion space */
312 *max_psize = bdev_max_capacity(vd->vd_bdev, v->vdev_wholedisk);
314 /* Based on the minimum sector size set the block size */
315 *physical_ashift = highbit64(MAX(physical_block_size,
316 SPA_MINBLOCKSIZE)) - 1;
318 *logical_ashift = highbit64(MAX(logical_block_size,
319 SPA_MINBLOCKSIZE)) - 1;
325 vdev_disk_close(vdev_t *v)
327 vdev_disk_t *vd = v->vdev_tsd;
329 if (v->vdev_reopening || vd == NULL)
332 if (vd->vd_bdev != NULL) {
333 blkdev_put(vd->vd_bdev,
334 vdev_bdev_mode(spa_mode(v->vdev_spa)) | FMODE_EXCL);
337 rw_destroy(&vd->vd_lock);
338 kmem_free(vd, sizeof (vdev_disk_t));
342 static dio_request_t *
343 vdev_disk_dio_alloc(int bio_count)
348 dr = kmem_zalloc(sizeof (dio_request_t) +
349 sizeof (struct bio *) * bio_count, KM_SLEEP);
351 atomic_set(&dr->dr_ref, 0);
352 dr->dr_bio_count = bio_count;
355 for (i = 0; i < dr->dr_bio_count; i++)
356 dr->dr_bio[i] = NULL;
363 vdev_disk_dio_free(dio_request_t *dr)
367 for (i = 0; i < dr->dr_bio_count; i++)
369 bio_put(dr->dr_bio[i]);
371 kmem_free(dr, sizeof (dio_request_t) +
372 sizeof (struct bio *) * dr->dr_bio_count);
376 vdev_disk_dio_get(dio_request_t *dr)
378 atomic_inc(&dr->dr_ref);
382 vdev_disk_dio_put(dio_request_t *dr)
384 int rc = atomic_dec_return(&dr->dr_ref);
387 * Free the dio_request when the last reference is dropped and
388 * ensure zio_interpret is called only once with the correct zio
391 zio_t *zio = dr->dr_zio;
392 int error = dr->dr_error;
394 vdev_disk_dio_free(dr);
397 zio->io_error = error;
398 ASSERT3S(zio->io_error, >=, 0);
400 vdev_disk_error(zio);
402 zio_delay_interrupt(zio);
409 BIO_END_IO_PROTO(vdev_disk_physio_completion, bio, error)
411 dio_request_t *dr = bio->bi_private;
414 if (dr->dr_error == 0) {
415 #ifdef HAVE_1ARG_BIO_END_IO_T
416 dr->dr_error = BIO_END_IO_ERROR(bio);
419 dr->dr_error = -(error);
420 else if (!test_bit(BIO_UPTODATE, &bio->bi_flags))
425 /* Drop reference acquired by __vdev_disk_physio */
426 rc = vdev_disk_dio_put(dr);
430 vdev_submit_bio_impl(struct bio *bio)
432 #ifdef HAVE_1ARG_SUBMIT_BIO
440 * preempt_schedule_notrace is GPL-only which breaks the ZFS build, so
441 * replace it with preempt_schedule under the following condition:
443 #if defined(CONFIG_ARM64) && \
444 defined(CONFIG_PREEMPTION) && \
445 defined(CONFIG_BLK_CGROUP)
446 #define preempt_schedule_notrace(x) preempt_schedule(x)
449 #ifdef HAVE_BIO_SET_DEV
450 #if defined(CONFIG_BLK_CGROUP) && defined(HAVE_BIO_SET_DEV_GPL_ONLY)
452 * The Linux 5.5 kernel updated percpu_ref_tryget() which is inlined by
453 * blkg_tryget() to use rcu_read_lock() instead of rcu_read_lock_sched().
454 * As a side effect the function was converted to GPL-only. Define our
455 * own version when needed which uses rcu_read_lock_sched().
457 #if defined(HAVE_BLKG_TRYGET_GPL_ONLY)
459 vdev_blkg_tryget(struct blkcg_gq *blkg)
461 struct percpu_ref *ref = &blkg->refcnt;
462 unsigned long __percpu *count;
465 rcu_read_lock_sched();
467 if (__ref_is_percpu(ref, &count)) {
468 this_cpu_inc(*count);
471 rc = atomic_long_inc_not_zero(&ref->count);
474 rcu_read_unlock_sched();
478 #elif defined(HAVE_BLKG_TRYGET)
479 #define vdev_blkg_tryget(bg) blkg_tryget(bg)
482 * The Linux 5.0 kernel updated the bio_set_dev() macro so it calls the
483 * GPL-only bio_associate_blkg() symbol thus inadvertently converting
484 * the entire macro. Provide a minimal version which always assigns the
485 * request queue's root_blkg to the bio.
488 vdev_bio_associate_blkg(struct bio *bio)
490 struct request_queue *q = bio->bi_disk->queue;
492 ASSERT3P(q, !=, NULL);
493 ASSERT3P(bio->bi_blkg, ==, NULL);
495 if (q->root_blkg && vdev_blkg_tryget(q->root_blkg))
496 bio->bi_blkg = q->root_blkg;
498 #define bio_associate_blkg vdev_bio_associate_blkg
502 * Provide a bio_set_dev() helper macro for pre-Linux 4.14 kernels.
505 bio_set_dev(struct bio *bio, struct block_device *bdev)
509 #endif /* HAVE_BIO_SET_DEV */
512 vdev_submit_bio(struct bio *bio)
514 struct bio_list *bio_list = current->bio_list;
515 current->bio_list = NULL;
516 vdev_submit_bio_impl(bio);
517 current->bio_list = bio_list;
521 __vdev_disk_physio(struct block_device *bdev, zio_t *zio,
522 size_t io_size, uint64_t io_offset, int rw, int flags)
527 int bio_size, bio_count = 16;
528 int i = 0, error = 0;
529 struct blk_plug plug;
532 * Accessing outside the block device is never allowed.
534 if (io_offset + io_size > bdev->bd_inode->i_size) {
535 vdev_dbgmsg(zio->io_vd,
536 "Illegal access %llu size %llu, device size %llu",
537 io_offset, io_size, i_size_read(bdev->bd_inode));
538 return (SET_ERROR(EIO));
542 dr = vdev_disk_dio_alloc(bio_count);
544 return (SET_ERROR(ENOMEM));
546 if (zio && !(zio->io_flags & (ZIO_FLAG_IO_RETRY | ZIO_FLAG_TRYHARD)))
547 bio_set_flags_failfast(bdev, &flags);
552 * When the IO size exceeds the maximum bio size for the request
553 * queue we are forced to break the IO in multiple bio's and wait
554 * for them all to complete. Ideally, all pool users will set
555 * their volume block size to match the maximum request size and
556 * the common case will be one bio per vdev IO request.
560 bio_offset = io_offset;
562 for (i = 0; i <= dr->dr_bio_count; i++) {
564 /* Finished constructing bio's for given buffer */
569 * By default only 'bio_count' bio's per dio are allowed.
570 * However, if we find ourselves in a situation where more
571 * are needed we allocate a larger dio and warn the user.
573 if (dr->dr_bio_count == i) {
574 vdev_disk_dio_free(dr);
579 /* bio_alloc() with __GFP_WAIT never returns NULL */
580 dr->dr_bio[i] = bio_alloc(GFP_NOIO,
581 MIN(abd_nr_pages_off(zio->io_abd, bio_size, abd_offset),
583 if (unlikely(dr->dr_bio[i] == NULL)) {
584 vdev_disk_dio_free(dr);
585 return (SET_ERROR(ENOMEM));
588 /* Matching put called by vdev_disk_physio_completion */
589 vdev_disk_dio_get(dr);
591 bio_set_dev(dr->dr_bio[i], bdev);
592 BIO_BI_SECTOR(dr->dr_bio[i]) = bio_offset >> 9;
593 dr->dr_bio[i]->bi_end_io = vdev_disk_physio_completion;
594 dr->dr_bio[i]->bi_private = dr;
595 bio_set_op_attrs(dr->dr_bio[i], rw, flags);
597 /* Remaining size is returned to become the new size */
598 bio_size = abd_bio_map_off(dr->dr_bio[i], zio->io_abd,
599 bio_size, abd_offset);
601 /* Advance in buffer and construct another bio if needed */
602 abd_offset += BIO_BI_SIZE(dr->dr_bio[i]);
603 bio_offset += BIO_BI_SIZE(dr->dr_bio[i]);
606 /* Extra reference to protect dio_request during vdev_submit_bio */
607 vdev_disk_dio_get(dr);
609 if (dr->dr_bio_count > 1)
610 blk_start_plug(&plug);
612 /* Submit all bio's associated with this dio */
613 for (i = 0; i < dr->dr_bio_count; i++)
615 vdev_submit_bio(dr->dr_bio[i]);
617 if (dr->dr_bio_count > 1)
618 blk_finish_plug(&plug);
620 (void) vdev_disk_dio_put(dr);
625 BIO_END_IO_PROTO(vdev_disk_io_flush_completion, bio, error)
627 zio_t *zio = bio->bi_private;
628 #ifdef HAVE_1ARG_BIO_END_IO_T
629 zio->io_error = BIO_END_IO_ERROR(bio);
631 zio->io_error = -error;
634 if (zio->io_error && (zio->io_error == EOPNOTSUPP))
635 zio->io_vd->vdev_nowritecache = B_TRUE;
638 ASSERT3S(zio->io_error, >=, 0);
640 vdev_disk_error(zio);
645 vdev_disk_io_flush(struct block_device *bdev, zio_t *zio)
647 struct request_queue *q;
650 q = bdev_get_queue(bdev);
652 return (SET_ERROR(ENXIO));
654 bio = bio_alloc(GFP_NOIO, 0);
655 /* bio_alloc() with __GFP_WAIT never returns NULL */
656 if (unlikely(bio == NULL))
657 return (SET_ERROR(ENOMEM));
659 bio->bi_end_io = vdev_disk_io_flush_completion;
660 bio->bi_private = zio;
661 bio_set_dev(bio, bdev);
663 vdev_submit_bio(bio);
664 invalidate_bdev(bdev);
670 vdev_disk_io_start(zio_t *zio)
672 vdev_t *v = zio->io_vd;
673 vdev_disk_t *vd = v->vdev_tsd;
674 unsigned long trim_flags = 0;
678 * If the vdev is closed, it's likely in the REMOVED or FAULTED state.
679 * Nothing to be done here but return failure.
682 zio->io_error = ENXIO;
687 rw_enter(&vd->vd_lock, RW_READER);
690 * If the vdev is closed, it's likely due to a failed reopen and is
691 * in the UNAVAIL state. Nothing to be done here but return failure.
693 if (vd->vd_bdev == NULL) {
694 rw_exit(&vd->vd_lock);
695 zio->io_error = ENXIO;
700 switch (zio->io_type) {
703 if (!vdev_readable(v)) {
704 rw_exit(&vd->vd_lock);
705 zio->io_error = SET_ERROR(ENXIO);
710 switch (zio->io_cmd) {
711 case DKIOCFLUSHWRITECACHE:
713 if (zfs_nocacheflush)
716 if (v->vdev_nowritecache) {
717 zio->io_error = SET_ERROR(ENOTSUP);
721 error = vdev_disk_io_flush(vd->vd_bdev, zio);
723 rw_exit(&vd->vd_lock);
727 zio->io_error = error;
732 zio->io_error = SET_ERROR(ENOTSUP);
735 rw_exit(&vd->vd_lock);
747 #if defined(BLKDEV_DISCARD_SECURE)
748 if (zio->io_trim_flags & ZIO_TRIM_SECURE)
749 trim_flags |= BLKDEV_DISCARD_SECURE;
751 zio->io_error = -blkdev_issue_discard(vd->vd_bdev,
752 zio->io_offset >> 9, zio->io_size >> 9, GFP_NOFS,
755 rw_exit(&vd->vd_lock);
760 rw_exit(&vd->vd_lock);
761 zio->io_error = SET_ERROR(ENOTSUP);
766 zio->io_target_timestamp = zio_handle_io_delay(zio);
767 error = __vdev_disk_physio(vd->vd_bdev, zio,
768 zio->io_size, zio->io_offset, rw, 0);
769 rw_exit(&vd->vd_lock);
772 zio->io_error = error;
779 vdev_disk_io_done(zio_t *zio)
782 * If the device returned EIO, we revalidate the media. If it is
783 * determined the media has changed this triggers the asynchronous
784 * removal of the device from the configuration.
786 if (zio->io_error == EIO) {
787 vdev_t *v = zio->io_vd;
788 vdev_disk_t *vd = v->vdev_tsd;
790 if (check_disk_change(vd->vd_bdev)) {
791 invalidate_bdev(vd->vd_bdev);
792 v->vdev_remove_wanted = B_TRUE;
793 spa_async_request(zio->io_spa, SPA_ASYNC_REMOVE);
799 vdev_disk_hold(vdev_t *vd)
801 ASSERT(spa_config_held(vd->vdev_spa, SCL_STATE, RW_WRITER));
803 /* We must have a pathname, and it must be absolute. */
804 if (vd->vdev_path == NULL || vd->vdev_path[0] != '/')
808 * Only prefetch path and devid info if the device has
811 if (vd->vdev_tsd != NULL)
817 vdev_disk_rele(vdev_t *vd)
819 ASSERT(spa_config_held(vd->vdev_spa, SCL_STATE, RW_WRITER));
821 /* XXX: Implement me as a vnode rele for the device */
824 vdev_ops_t vdev_disk_ops = {
825 .vdev_op_open = vdev_disk_open,
826 .vdev_op_close = vdev_disk_close,
827 .vdev_op_asize = vdev_default_asize,
828 .vdev_op_io_start = vdev_disk_io_start,
829 .vdev_op_io_done = vdev_disk_io_done,
830 .vdev_op_state_change = NULL,
831 .vdev_op_need_resilver = NULL,
832 .vdev_op_hold = vdev_disk_hold,
833 .vdev_op_rele = vdev_disk_rele,
834 .vdev_op_remap = NULL,
835 .vdev_op_xlate = vdev_default_xlate,
836 .vdev_op_type = VDEV_TYPE_DISK, /* name of this vdev type */
837 .vdev_op_leaf = B_TRUE /* leaf vdev */
841 * The zfs_vdev_scheduler module option has been deprecated. Setting this
842 * value no longer has any effect. It has not yet been entirely removed
843 * to allow the module to be loaded if this option is specified in the
844 * /etc/modprobe.d/zfs.conf file. The following warning will be logged.
847 param_set_vdev_scheduler(const char *val, zfs_kernel_param_t *kp)
849 int error = param_set_charp(val, kp);
851 printk(KERN_INFO "The 'zfs_vdev_scheduler' module option "
852 "is not supported.\n");
858 char *zfs_vdev_scheduler = "unused";
859 module_param_call(zfs_vdev_scheduler, param_set_vdev_scheduler,
860 param_get_charp, &zfs_vdev_scheduler, 0644);
861 MODULE_PARM_DESC(zfs_vdev_scheduler, "I/O scheduler");
864 param_set_min_auto_ashift(const char *buf, zfs_kernel_param_t *kp)
869 error = kstrtoull(buf, 0, &val);
871 return (SET_ERROR(error));
873 if (val < ASHIFT_MIN || val > zfs_vdev_max_auto_ashift)
874 return (SET_ERROR(-EINVAL));
876 error = param_set_ulong(buf, kp);
878 return (SET_ERROR(error));
884 param_set_max_auto_ashift(const char *buf, zfs_kernel_param_t *kp)
889 error = kstrtoull(buf, 0, &val);
891 return (SET_ERROR(error));
893 if (val > ASHIFT_MAX || val < zfs_vdev_min_auto_ashift)
894 return (SET_ERROR(-EINVAL));
896 error = param_set_ulong(buf, kp);
898 return (SET_ERROR(error));