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, 2014 by Delphix. All rights reserved.
29 #include <sys/zfs_context.h>
31 #include <sys/vdev_disk.h>
32 #include <sys/vdev_impl.h>
33 #include <sys/fs/zfs.h>
35 #include <sys/sunldi.h>
37 char *zfs_vdev_scheduler
= VDEV_SCHEDULER
;
38 static void *zfs_vdev_holder
= VDEV_HOLDER
;
41 * Virtual device vector for disks.
43 typedef struct dio_request
{
44 struct completion dr_comp
; /* Completion for sync IO */
45 atomic_t dr_ref
; /* References */
46 zio_t
*dr_zio
; /* Parent ZIO */
47 int dr_rw
; /* Read/Write */
48 int dr_error
; /* Bio error */
49 int dr_bio_count
; /* Count of bio's */
50 struct bio
*dr_bio
[0]; /* Attached bio's */
54 #ifdef HAVE_OPEN_BDEV_EXCLUSIVE
56 vdev_bdev_mode(int smode
)
60 ASSERT3S(smode
& (FREAD
| FWRITE
), !=, 0);
72 vdev_bdev_mode(int smode
)
76 ASSERT3S(smode
& (FREAD
| FWRITE
), !=, 0);
78 if ((smode
& FREAD
) && !(smode
& FWRITE
))
83 #endif /* HAVE_OPEN_BDEV_EXCLUSIVE */
86 bdev_capacity(struct block_device
*bdev
)
88 struct hd_struct
*part
= bdev
->bd_part
;
90 /* The partition capacity referenced by the block device */
92 return (part
->nr_sects
<< 9);
94 /* Otherwise assume the full device capacity */
95 return (get_capacity(bdev
->bd_disk
) << 9);
99 vdev_disk_error(zio_t
*zio
)
102 printk("ZFS: zio error=%d type=%d offset=%llu size=%llu "
103 "flags=%x delay=%llu\n", zio
->io_error
, zio
->io_type
,
104 (u_longlong_t
)zio
->io_offset
, (u_longlong_t
)zio
->io_size
,
105 zio
->io_flags
, (u_longlong_t
)zio
->io_delay
);
110 * Use the Linux 'noop' elevator for zfs managed block devices. This
111 * strikes the ideal balance by allowing the zfs elevator to do all
112 * request ordering and prioritization. While allowing the Linux
113 * elevator to do the maximum front/back merging allowed by the
114 * physical device. This yields the largest possible requests for
115 * the device with the lowest total overhead.
118 vdev_elevator_switch(vdev_t
*v
, char *elevator
)
120 vdev_disk_t
*vd
= v
->vdev_tsd
;
121 struct block_device
*bdev
= vd
->vd_bdev
;
122 struct request_queue
*q
= bdev_get_queue(bdev
);
123 char *device
= bdev
->bd_disk
->disk_name
;
127 * Skip devices which are not whole disks (partitions).
128 * Device-mapper devices are excepted since they may be whole
129 * disks despite the vdev_wholedisk flag, in which case we can
130 * and should switch the elevator. If the device-mapper device
131 * does not have an elevator (i.e. dm-raid, dm-crypt, etc.) the
132 * "Skip devices without schedulers" check below will fail.
134 if (!v
->vdev_wholedisk
&& strncmp(device
, "dm-", 3) != 0)
137 /* Skip devices without schedulers (loop, ram, dm, etc) */
138 if (!q
->elevator
|| !blk_queue_stackable(q
))
141 /* Leave existing scheduler when set to "none" */
142 if (strncmp(elevator
, "none", 4) && (strlen(elevator
) == 4) == 0)
145 #ifdef HAVE_ELEVATOR_CHANGE
146 error
= elevator_change(q
, elevator
);
149 * For pre-2.6.36 kernels elevator_change() is not available.
150 * Therefore we fall back to using a usermodehelper to echo the
151 * elevator into sysfs; This requires /bin/echo and sysfs to be
152 * mounted which may not be true early in the boot process.
154 #define SET_SCHEDULER_CMD \
155 "exec 0</dev/null " \
156 " 1>/sys/block/%s/queue/scheduler " \
161 char *argv
[] = { "/bin/sh", "-c", NULL
, NULL
};
162 char *envp
[] = { NULL
};
164 argv
[2] = kmem_asprintf(SET_SCHEDULER_CMD
, device
, elevator
);
165 error
= call_usermodehelper(argv
[0], argv
, envp
, UMH_WAIT_PROC
);
168 #endif /* HAVE_ELEVATOR_CHANGE */
170 printk("ZFS: Unable to set \"%s\" scheduler for %s (%s): %d\n",
171 elevator
, v
->vdev_path
, device
, error
);
177 * Expanding a whole disk vdev involves invoking BLKRRPART on the
178 * whole disk device. This poses a problem, because BLKRRPART will
179 * return EBUSY if one of the disk's partitions is open. That's why
180 * we have to do it here, just before opening the data partition.
181 * Unfortunately, BLKRRPART works by dropping all partitions and
182 * recreating them, which means that for a short time window, all
183 * /dev/sdxN device files disappear (until udev recreates them).
184 * This means two things:
185 * - When we open the data partition just after a BLKRRPART, we
186 * can't do it using the normal device file path because of the
187 * obvious race condition with udev. Instead, we use reliable
188 * kernel APIs to get a handle to the new partition device from
189 * the whole disk device.
190 * - Because vdev_disk_open() initially needs to find the device
191 * using its path, multiple vdev_disk_open() invocations in
192 * short succession on the same disk with BLKRRPARTs in the
193 * middle have a high probability of failure (because of the
194 * race condition with udev). A typical situation where this
195 * might happen is when the zpool userspace tool does a
196 * TRYIMPORT immediately followed by an IMPORT. For this
197 * reason, we only invoke BLKRRPART in the module when strictly
198 * necessary (zpool online -e case), and rely on userspace to
199 * do it when possible.
201 static struct block_device
*
202 vdev_disk_rrpart(const char *path
, int mode
, vdev_disk_t
*vd
)
204 #if defined(HAVE_3ARG_BLKDEV_GET) && defined(HAVE_GET_GENDISK)
205 struct block_device
*bdev
, *result
= ERR_PTR(-ENXIO
);
206 struct gendisk
*disk
;
209 bdev
= vdev_bdev_open(path
, vdev_bdev_mode(mode
), zfs_vdev_holder
);
213 disk
= get_gendisk(bdev
->bd_dev
, &partno
);
214 vdev_bdev_close(bdev
, vdev_bdev_mode(mode
));
217 bdev
= bdget(disk_devt(disk
));
219 error
= blkdev_get(bdev
, vdev_bdev_mode(mode
), vd
);
221 error
= ioctl_by_bdev(bdev
, BLKRRPART
, 0);
222 vdev_bdev_close(bdev
, vdev_bdev_mode(mode
));
225 bdev
= bdget_disk(disk
, partno
);
227 error
= blkdev_get(bdev
,
228 vdev_bdev_mode(mode
) | FMODE_EXCL
, vd
);
237 return (ERR_PTR(-EOPNOTSUPP
));
238 #endif /* defined(HAVE_3ARG_BLKDEV_GET) && defined(HAVE_GET_GENDISK) */
242 vdev_disk_open(vdev_t
*v
, uint64_t *psize
, uint64_t *max_psize
,
245 struct block_device
*bdev
= ERR_PTR(-ENXIO
);
247 int mode
, block_size
;
249 /* Must have a pathname and it must be absolute. */
250 if (v
->vdev_path
== NULL
|| v
->vdev_path
[0] != '/') {
251 v
->vdev_stat
.vs_aux
= VDEV_AUX_BAD_LABEL
;
256 * Reopen the device if it's not currently open. Otherwise,
257 * just update the physical size of the device.
259 if (v
->vdev_tsd
!= NULL
) {
260 ASSERT(v
->vdev_reopening
);
265 vd
= kmem_zalloc(sizeof (vdev_disk_t
), KM_SLEEP
);
270 * Devices are always opened by the path provided at configuration
271 * time. This means that if the provided path is a udev by-id path
272 * then drives may be recabled without an issue. If the provided
273 * path is a udev by-path path, then the physical location information
274 * will be preserved. This can be critical for more complicated
275 * configurations where drives are located in specific physical
276 * locations to maximize the systems tolerence to component failure.
277 * Alternatively, you can provide your own udev rule to flexibly map
278 * the drives as you see fit. It is not advised that you use the
279 * /dev/[hd]d devices which may be reordered due to probing order.
280 * Devices in the wrong locations will be detected by the higher
281 * level vdev validation.
283 mode
= spa_mode(v
->vdev_spa
);
284 if (v
->vdev_wholedisk
&& v
->vdev_expanding
)
285 bdev
= vdev_disk_rrpart(v
->vdev_path
, mode
, vd
);
287 bdev
= vdev_bdev_open(v
->vdev_path
,
288 vdev_bdev_mode(mode
), zfs_vdev_holder
);
290 kmem_free(vd
, sizeof (vdev_disk_t
));
291 return (-PTR_ERR(bdev
));
298 /* Determine the physical block size */
299 block_size
= vdev_bdev_block_size(vd
->vd_bdev
);
301 /* Clear the nowritecache bit, causes vdev_reopen() to try again. */
302 v
->vdev_nowritecache
= B_FALSE
;
304 /* Physical volume size in bytes */
305 *psize
= bdev_capacity(vd
->vd_bdev
);
307 /* TODO: report possible expansion size */
310 /* Based on the minimum sector size set the block size */
311 *ashift
= highbit64(MAX(block_size
, SPA_MINBLOCKSIZE
)) - 1;
313 /* Try to set the io scheduler elevator algorithm */
314 (void) vdev_elevator_switch(v
, zfs_vdev_scheduler
);
320 vdev_disk_close(vdev_t
*v
)
322 vdev_disk_t
*vd
= v
->vdev_tsd
;
324 if (v
->vdev_reopening
|| vd
== NULL
)
327 if (vd
->vd_bdev
!= NULL
)
328 vdev_bdev_close(vd
->vd_bdev
,
329 vdev_bdev_mode(spa_mode(v
->vdev_spa
)));
331 kmem_free(vd
, sizeof (vdev_disk_t
));
335 static dio_request_t
*
336 vdev_disk_dio_alloc(int bio_count
)
341 dr
= kmem_zalloc(sizeof (dio_request_t
) +
342 sizeof (struct bio
*) * bio_count
, KM_SLEEP
);
344 init_completion(&dr
->dr_comp
);
345 atomic_set(&dr
->dr_ref
, 0);
346 dr
->dr_bio_count
= bio_count
;
349 for (i
= 0; i
< dr
->dr_bio_count
; i
++)
350 dr
->dr_bio
[i
] = NULL
;
357 vdev_disk_dio_free(dio_request_t
*dr
)
361 for (i
= 0; i
< dr
->dr_bio_count
; i
++)
363 bio_put(dr
->dr_bio
[i
]);
365 kmem_free(dr
, sizeof (dio_request_t
) +
366 sizeof (struct bio
*) * dr
->dr_bio_count
);
370 vdev_disk_dio_is_sync(dio_request_t
*dr
)
372 #ifdef HAVE_BIO_RW_SYNC
373 /* BIO_RW_SYNC preferred interface from 2.6.12-2.6.29 */
374 return (dr
->dr_rw
& (1 << BIO_RW_SYNC
));
376 #ifdef HAVE_BIO_RW_SYNCIO
377 /* BIO_RW_SYNCIO preferred interface from 2.6.30-2.6.35 */
378 return (dr
->dr_rw
& (1 << BIO_RW_SYNCIO
));
381 /* REQ_SYNC preferred interface from 2.6.36-2.6.xx */
382 return (dr
->dr_rw
& REQ_SYNC
);
384 #error "Unable to determine bio sync flag"
385 #endif /* HAVE_REQ_SYNC */
386 #endif /* HAVE_BIO_RW_SYNC */
387 #endif /* HAVE_BIO_RW_SYNCIO */
391 vdev_disk_dio_get(dio_request_t
*dr
)
393 atomic_inc(&dr
->dr_ref
);
397 vdev_disk_dio_put(dio_request_t
*dr
)
399 int rc
= atomic_dec_return(&dr
->dr_ref
);
402 * Free the dio_request when the last reference is dropped and
403 * ensure zio_interpret is called only once with the correct zio
406 zio_t
*zio
= dr
->dr_zio
;
407 int error
= dr
->dr_error
;
409 vdev_disk_dio_free(dr
);
412 zio
->io_delay
= jiffies_64
- zio
->io_delay
;
413 zio
->io_error
= error
;
414 ASSERT3S(zio
->io_error
, >=, 0);
416 vdev_disk_error(zio
);
424 BIO_END_IO_PROTO(vdev_disk_physio_completion
, bio
, size
, error
)
426 dio_request_t
*dr
= bio
->bi_private
;
429 /* Fatal error but print some useful debugging before asserting */
431 PANIC("dr == NULL, bio->bi_private == NULL\n"
432 "bi_next: %p, bi_flags: %lx, bi_rw: %lu, bi_vcnt: %d\n"
433 "bi_idx: %d, bi_size: %d, bi_end_io: %p, bi_cnt: %d\n",
434 bio
->bi_next
, bio
->bi_flags
, bio
->bi_rw
, bio
->bi_vcnt
,
435 BIO_BI_IDX(bio
), BIO_BI_SIZE(bio
), bio
->bi_end_io
,
436 atomic_read(&bio
->bi_cnt
));
438 #ifndef HAVE_2ARGS_BIO_END_IO_T
439 if (BIO_BI_SIZE(bio
))
441 #endif /* HAVE_2ARGS_BIO_END_IO_T */
443 if (error
== 0 && !test_bit(BIO_UPTODATE
, &bio
->bi_flags
))
446 if (dr
->dr_error
== 0)
447 dr
->dr_error
= -error
;
449 /* Drop reference aquired by __vdev_disk_physio */
450 rc
= vdev_disk_dio_put(dr
);
452 /* Wake up synchronous waiter this is the last outstanding bio */
453 if ((rc
== 1) && vdev_disk_dio_is_sync(dr
))
454 complete(&dr
->dr_comp
);
456 BIO_END_IO_RETURN(0);
459 static inline unsigned long
460 bio_nr_pages(void *bio_ptr
, unsigned int bio_size
)
462 return ((((unsigned long)bio_ptr
+ bio_size
+ PAGE_SIZE
- 1) >>
463 PAGE_SHIFT
) - ((unsigned long)bio_ptr
>> PAGE_SHIFT
));
467 bio_map(struct bio
*bio
, void *bio_ptr
, unsigned int bio_size
)
469 unsigned int offset
, size
, i
;
472 offset
= offset_in_page(bio_ptr
);
473 for (i
= 0; i
< bio
->bi_max_vecs
; i
++) {
474 size
= PAGE_SIZE
- offset
;
482 if (is_vmalloc_addr(bio_ptr
))
483 page
= vmalloc_to_page(bio_ptr
);
485 page
= virt_to_page(bio_ptr
);
488 * Some network related block device uses tcp_sendpage, which
489 * doesn't behave well when using 0-count page, this is a
490 * safety net to catch them.
492 ASSERT3S(page_count(page
), >, 0);
494 if (bio_add_page(bio
, page
, size
, offset
) != size
)
506 __vdev_disk_physio(struct block_device
*bdev
, zio_t
*zio
, caddr_t kbuf_ptr
,
507 size_t kbuf_size
, uint64_t kbuf_offset
, int flags
)
512 int bio_size
, bio_count
= 16;
513 int i
= 0, error
= 0;
515 ASSERT3U(kbuf_offset
+ kbuf_size
, <=, bdev
->bd_inode
->i_size
);
518 dr
= vdev_disk_dio_alloc(bio_count
);
522 if (zio
&& !(zio
->io_flags
& (ZIO_FLAG_IO_RETRY
| ZIO_FLAG_TRYHARD
)))
523 bio_set_flags_failfast(bdev
, &flags
);
529 * When the IO size exceeds the maximum bio size for the request
530 * queue we are forced to break the IO in multiple bio's and wait
531 * for them all to complete. Ideally, all pool users will set
532 * their volume block size to match the maximum request size and
533 * the common case will be one bio per vdev IO request.
536 bio_offset
= kbuf_offset
;
537 bio_size
= kbuf_size
;
538 for (i
= 0; i
<= dr
->dr_bio_count
; i
++) {
540 /* Finished constructing bio's for given buffer */
545 * By default only 'bio_count' bio's per dio are allowed.
546 * However, if we find ourselves in a situation where more
547 * are needed we allocate a larger dio and warn the user.
549 if (dr
->dr_bio_count
== i
) {
550 vdev_disk_dio_free(dr
);
555 dr
->dr_bio
[i
] = bio_alloc(GFP_NOIO
,
556 bio_nr_pages(bio_ptr
, bio_size
));
557 /* bio_alloc() with __GFP_WAIT never returns NULL */
558 if (unlikely(dr
->dr_bio
[i
] == NULL
)) {
559 vdev_disk_dio_free(dr
);
563 /* Matching put called by vdev_disk_physio_completion */
564 vdev_disk_dio_get(dr
);
566 dr
->dr_bio
[i
]->bi_bdev
= bdev
;
567 BIO_BI_SECTOR(dr
->dr_bio
[i
]) = bio_offset
>> 9;
568 dr
->dr_bio
[i
]->bi_rw
= dr
->dr_rw
;
569 dr
->dr_bio
[i
]->bi_end_io
= vdev_disk_physio_completion
;
570 dr
->dr_bio
[i
]->bi_private
= dr
;
572 /* Remaining size is returned to become the new size */
573 bio_size
= bio_map(dr
->dr_bio
[i
], bio_ptr
, bio_size
);
575 /* Advance in buffer and construct another bio if needed */
576 bio_ptr
+= BIO_BI_SIZE(dr
->dr_bio
[i
]);
577 bio_offset
+= BIO_BI_SIZE(dr
->dr_bio
[i
]);
580 /* Extra reference to protect dio_request during submit_bio */
581 vdev_disk_dio_get(dr
);
583 zio
->io_delay
= jiffies_64
;
585 /* Submit all bio's associated with this dio */
586 for (i
= 0; i
< dr
->dr_bio_count
; i
++)
588 submit_bio(dr
->dr_rw
, dr
->dr_bio
[i
]);
591 * On synchronous blocking requests we wait for all bio the completion
592 * callbacks to run. We will be woken when the last callback runs
593 * for this dio. We are responsible for putting the last dio_request
594 * reference will in turn put back the last bio references. The
595 * only synchronous consumer is vdev_disk_read_rootlabel() all other
596 * IO originating from vdev_disk_io_start() is asynchronous.
598 if (vdev_disk_dio_is_sync(dr
)) {
599 wait_for_completion(&dr
->dr_comp
);
600 error
= dr
->dr_error
;
601 ASSERT3S(atomic_read(&dr
->dr_ref
), ==, 1);
604 (void) vdev_disk_dio_put(dr
);
610 vdev_disk_physio(struct block_device
*bdev
, caddr_t kbuf
,
611 size_t size
, uint64_t offset
, int flags
)
613 bio_set_flags_failfast(bdev
, &flags
);
614 return (__vdev_disk_physio(bdev
, NULL
, kbuf
, size
, offset
, flags
));
617 BIO_END_IO_PROTO(vdev_disk_io_flush_completion
, bio
, size
, rc
)
619 zio_t
*zio
= bio
->bi_private
;
621 zio
->io_delay
= jiffies_64
- zio
->io_delay
;
623 if (rc
&& (rc
== -EOPNOTSUPP
))
624 zio
->io_vd
->vdev_nowritecache
= B_TRUE
;
627 ASSERT3S(zio
->io_error
, >=, 0);
629 vdev_disk_error(zio
);
632 BIO_END_IO_RETURN(0);
636 vdev_disk_io_flush(struct block_device
*bdev
, zio_t
*zio
)
638 struct request_queue
*q
;
641 q
= bdev_get_queue(bdev
);
645 bio
= bio_alloc(GFP_NOIO
, 0);
646 /* bio_alloc() with __GFP_WAIT never returns NULL */
647 if (unlikely(bio
== NULL
))
650 bio
->bi_end_io
= vdev_disk_io_flush_completion
;
651 bio
->bi_private
= zio
;
653 zio
->io_delay
= jiffies_64
;
654 submit_bio(VDEV_WRITE_FLUSH_FUA
, bio
);
655 invalidate_bdev(bdev
);
661 vdev_disk_io_start(zio_t
*zio
)
663 vdev_t
*v
= zio
->io_vd
;
664 vdev_disk_t
*vd
= v
->vdev_tsd
;
667 switch (zio
->io_type
) {
670 if (!vdev_readable(v
)) {
671 zio
->io_error
= SET_ERROR(ENXIO
);
676 switch (zio
->io_cmd
) {
677 case DKIOCFLUSHWRITECACHE
:
679 if (zfs_nocacheflush
)
682 if (v
->vdev_nowritecache
) {
683 zio
->io_error
= SET_ERROR(ENOTSUP
);
687 error
= vdev_disk_io_flush(vd
->vd_bdev
, zio
);
691 zio
->io_error
= error
;
692 if (error
== ENOTSUP
)
693 v
->vdev_nowritecache
= B_TRUE
;
698 zio
->io_error
= SET_ERROR(ENOTSUP
);
712 zio
->io_error
= SET_ERROR(ENOTSUP
);
717 error
= __vdev_disk_physio(vd
->vd_bdev
, zio
, zio
->io_data
,
718 zio
->io_size
, zio
->io_offset
, flags
);
720 zio
->io_error
= error
;
727 vdev_disk_io_done(zio_t
*zio
)
730 * If the device returned EIO, we revalidate the media. If it is
731 * determined the media has changed this triggers the asynchronous
732 * removal of the device from the configuration.
734 if (zio
->io_error
== EIO
) {
735 vdev_t
*v
= zio
->io_vd
;
736 vdev_disk_t
*vd
= v
->vdev_tsd
;
738 if (check_disk_change(vd
->vd_bdev
)) {
739 vdev_bdev_invalidate(vd
->vd_bdev
);
740 v
->vdev_remove_wanted
= B_TRUE
;
741 spa_async_request(zio
->io_spa
, SPA_ASYNC_REMOVE
);
747 vdev_disk_hold(vdev_t
*vd
)
749 ASSERT(spa_config_held(vd
->vdev_spa
, SCL_STATE
, RW_WRITER
));
751 /* We must have a pathname, and it must be absolute. */
752 if (vd
->vdev_path
== NULL
|| vd
->vdev_path
[0] != '/')
756 * Only prefetch path and devid info if the device has
759 if (vd
->vdev_tsd
!= NULL
)
762 /* XXX: Implement me as a vnode lookup for the device */
763 vd
->vdev_name_vp
= NULL
;
764 vd
->vdev_devid_vp
= NULL
;
768 vdev_disk_rele(vdev_t
*vd
)
770 ASSERT(spa_config_held(vd
->vdev_spa
, SCL_STATE
, RW_WRITER
));
772 /* XXX: Implement me as a vnode rele for the device */
775 vdev_ops_t vdev_disk_ops
= {
784 VDEV_TYPE_DISK
, /* name of this vdev type */
785 B_TRUE
/* leaf vdev */
789 * Given the root disk device devid or pathname, read the label from
790 * the device, and construct a configuration nvlist.
793 vdev_disk_read_rootlabel(char *devpath
, char *devid
, nvlist_t
**config
)
795 struct block_device
*bdev
;
800 bdev
= vdev_bdev_open(devpath
, vdev_bdev_mode(FREAD
), zfs_vdev_holder
);
802 return (-PTR_ERR(bdev
));
804 s
= bdev_capacity(bdev
);
806 vdev_bdev_close(bdev
, vdev_bdev_mode(FREAD
));
810 size
= P2ALIGN_TYPED(s
, sizeof (vdev_label_t
), uint64_t);
811 label
= vmem_alloc(sizeof (vdev_label_t
), KM_SLEEP
);
813 for (i
= 0; i
< VDEV_LABELS
; i
++) {
814 uint64_t offset
, state
, txg
= 0;
816 /* read vdev label */
817 offset
= vdev_label_offset(size
, i
, 0);
818 if (vdev_disk_physio(bdev
, (caddr_t
)label
,
819 VDEV_SKIP_SIZE
+ VDEV_PHYS_SIZE
, offset
, READ_SYNC
) != 0)
822 if (nvlist_unpack(label
->vl_vdev_phys
.vp_nvlist
,
823 sizeof (label
->vl_vdev_phys
.vp_nvlist
), config
, 0) != 0) {
828 if (nvlist_lookup_uint64(*config
, ZPOOL_CONFIG_POOL_STATE
,
829 &state
) != 0 || state
>= POOL_STATE_DESTROYED
) {
830 nvlist_free(*config
);
835 if (nvlist_lookup_uint64(*config
, ZPOOL_CONFIG_POOL_TXG
,
836 &txg
) != 0 || txg
== 0) {
837 nvlist_free(*config
);
845 vmem_free(label
, sizeof (vdev_label_t
));
846 vdev_bdev_close(bdev
, vdev_bdev_mode(FREAD
));
851 module_param(zfs_vdev_scheduler
, charp
, 0644);
852 MODULE_PARM_DESC(zfs_vdev_scheduler
, "I/O scheduler");