2772 lines
70 KiB
C
2772 lines
70 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).
|
||
|
* Rewritten for Linux by Brian Behlendorf <behlendorf1@llnl.gov>.
|
||
|
* LLNL-CODE-403049.
|
||
|
*
|
||
|
* ZFS volume emulation driver.
|
||
|
*
|
||
|
* Makes a DMU object look like a volume of arbitrary size, up to 2^64 bytes.
|
||
|
* Volumes are accessed through the symbolic links named:
|
||
|
*
|
||
|
* /dev/<pool_name>/<dataset_name>
|
||
|
*
|
||
|
* Volumes are persistent through reboot and module load. No user command
|
||
|
* needs to be run before opening and using a device.
|
||
|
*
|
||
|
* Copyright 2014 Nexenta Systems, Inc. All rights reserved.
|
||
|
* Copyright (c) 2016 Actifio, Inc. All rights reserved.
|
||
|
* Copyright (c) 2012, 2019 by Delphix. All rights reserved.
|
||
|
*/
|
||
|
|
||
|
/*
|
||
|
* Note on locking of zvol state structures.
|
||
|
*
|
||
|
* These structures are used to maintain internal state used to emulate block
|
||
|
* devices on top of zvols. In particular, management of device minor number
|
||
|
* operations - create, remove, rename, and set_snapdev - involves access to
|
||
|
* these structures. The zvol_state_lock is primarily used to protect the
|
||
|
* zvol_state_list. The zv->zv_state_lock is used to protect the contents
|
||
|
* of the zvol_state_t structures, as well as to make sure that when the
|
||
|
* time comes to remove the structure from the list, it is not in use, and
|
||
|
* therefore, it can be taken off zvol_state_list and freed.
|
||
|
*
|
||
|
* The zv_suspend_lock was introduced to allow for suspending I/O to a zvol,
|
||
|
* e.g. for the duration of receive and rollback operations. This lock can be
|
||
|
* held for significant periods of time. Given that it is undesirable to hold
|
||
|
* mutexes for long periods of time, the following lock ordering applies:
|
||
|
* - take zvol_state_lock if necessary, to protect zvol_state_list
|
||
|
* - take zv_suspend_lock if necessary, by the code path in question
|
||
|
* - take zv_state_lock to protect zvol_state_t
|
||
|
*
|
||
|
* The minor operations are issued to spa->spa_zvol_taskq queues, that are
|
||
|
* single-threaded (to preserve order of minor operations), and are executed
|
||
|
* through the zvol_task_cb that dispatches the specific operations. Therefore,
|
||
|
* these operations are serialized per pool. Consequently, we can be certain
|
||
|
* that for a given zvol, there is only one operation at a time in progress.
|
||
|
* That is why one can be sure that first, zvol_state_t for a given zvol is
|
||
|
* allocated and placed on zvol_state_list, and then other minor operations
|
||
|
* for this zvol are going to proceed in the order of issue.
|
||
|
*
|
||
|
* It is also worth keeping in mind that once add_disk() is called, the zvol is
|
||
|
* announced to the world, and zvol_open()/zvol_release() can be called at any
|
||
|
* time. Incidentally, add_disk() itself calls zvol_open()->zvol_first_open()
|
||
|
* and zvol_release()->zvol_last_close() directly as well.
|
||
|
*/
|
||
|
|
||
|
#include <sys/dataset_kstats.h>
|
||
|
#include <sys/dbuf.h>
|
||
|
#include <sys/dmu_traverse.h>
|
||
|
#include <sys/dsl_dataset.h>
|
||
|
#include <sys/dsl_prop.h>
|
||
|
#include <sys/dsl_dir.h>
|
||
|
#include <sys/zap.h>
|
||
|
#include <sys/zfeature.h>
|
||
|
#include <sys/zil_impl.h>
|
||
|
#include <sys/dmu_tx.h>
|
||
|
#include <sys/zio.h>
|
||
|
#include <sys/zfs_rlock.h>
|
||
|
#include <sys/spa_impl.h>
|
||
|
#include <sys/zvol.h>
|
||
|
|
||
|
#include <linux/blkdev_compat.h>
|
||
|
#include <linux/task_io_accounting_ops.h>
|
||
|
|
||
|
unsigned int zvol_inhibit_dev = 0;
|
||
|
unsigned int zvol_major = ZVOL_MAJOR;
|
||
|
unsigned int zvol_threads = 32;
|
||
|
unsigned int zvol_request_sync = 0;
|
||
|
unsigned int zvol_prefetch_bytes = (128 * 1024);
|
||
|
unsigned long zvol_max_discard_blocks = 16384;
|
||
|
unsigned int zvol_volmode = ZFS_VOLMODE_GEOM;
|
||
|
|
||
|
static taskq_t *zvol_taskq;
|
||
|
static krwlock_t zvol_state_lock;
|
||
|
static list_t zvol_state_list;
|
||
|
|
||
|
#define ZVOL_HT_SIZE 1024
|
||
|
static struct hlist_head *zvol_htable;
|
||
|
#define ZVOL_HT_HEAD(hash) (&zvol_htable[(hash) & (ZVOL_HT_SIZE-1)])
|
||
|
|
||
|
static struct ida zvol_ida;
|
||
|
|
||
|
/*
|
||
|
* The in-core state of each volume.
|
||
|
*/
|
||
|
struct zvol_state {
|
||
|
char zv_name[MAXNAMELEN]; /* name */
|
||
|
uint64_t zv_volsize; /* advertised space */
|
||
|
uint64_t zv_volblocksize; /* volume block size */
|
||
|
objset_t *zv_objset; /* objset handle */
|
||
|
uint32_t zv_flags; /* ZVOL_* flags */
|
||
|
uint32_t zv_open_count; /* open counts */
|
||
|
uint32_t zv_changed; /* disk changed */
|
||
|
zilog_t *zv_zilog; /* ZIL handle */
|
||
|
rangelock_t zv_rangelock; /* for range locking */
|
||
|
dnode_t *zv_dn; /* dnode hold */
|
||
|
dev_t zv_dev; /* device id */
|
||
|
struct gendisk *zv_disk; /* generic disk */
|
||
|
struct request_queue *zv_queue; /* request queue */
|
||
|
dataset_kstats_t zv_kstat; /* zvol kstats */
|
||
|
list_node_t zv_next; /* next zvol_state_t linkage */
|
||
|
uint64_t zv_hash; /* name hash */
|
||
|
struct hlist_node zv_hlink; /* hash link */
|
||
|
kmutex_t zv_state_lock; /* protects zvol_state_t */
|
||
|
atomic_t zv_suspend_ref; /* refcount for suspend */
|
||
|
krwlock_t zv_suspend_lock; /* suspend lock */
|
||
|
};
|
||
|
|
||
|
typedef enum {
|
||
|
ZVOL_ASYNC_CREATE_MINORS,
|
||
|
ZVOL_ASYNC_REMOVE_MINORS,
|
||
|
ZVOL_ASYNC_RENAME_MINORS,
|
||
|
ZVOL_ASYNC_SET_SNAPDEV,
|
||
|
ZVOL_ASYNC_SET_VOLMODE,
|
||
|
ZVOL_ASYNC_MAX
|
||
|
} zvol_async_op_t;
|
||
|
|
||
|
typedef struct {
|
||
|
zvol_async_op_t op;
|
||
|
char pool[MAXNAMELEN];
|
||
|
char name1[MAXNAMELEN];
|
||
|
char name2[MAXNAMELEN];
|
||
|
zprop_source_t source;
|
||
|
uint64_t value;
|
||
|
} zvol_task_t;
|
||
|
|
||
|
#define ZVOL_RDONLY 0x1
|
||
|
/*
|
||
|
* Whether the zvol has been written to (as opposed to ZVOL_RDONLY, which
|
||
|
* specifies whether or not the zvol _can_ be written to)
|
||
|
*/
|
||
|
#define ZVOL_WRITTEN_TO 0x2
|
||
|
|
||
|
static uint64_t
|
||
|
zvol_name_hash(const char *name)
|
||
|
{
|
||
|
int i;
|
||
|
uint64_t crc = -1ULL;
|
||
|
uint8_t *p = (uint8_t *)name;
|
||
|
ASSERT(zfs_crc64_table[128] == ZFS_CRC64_POLY);
|
||
|
for (i = 0; i < MAXNAMELEN - 1 && *p; i++, p++) {
|
||
|
crc = (crc >> 8) ^ zfs_crc64_table[(crc ^ (*p)) & 0xFF];
|
||
|
}
|
||
|
return (crc);
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Find a zvol_state_t given the full major+minor dev_t. If found,
|
||
|
* return with zv_state_lock taken, otherwise, return (NULL) without
|
||
|
* taking zv_state_lock.
|
||
|
*/
|
||
|
static zvol_state_t *
|
||
|
zvol_find_by_dev(dev_t dev)
|
||
|
{
|
||
|
zvol_state_t *zv;
|
||
|
|
||
|
rw_enter(&zvol_state_lock, RW_READER);
|
||
|
for (zv = list_head(&zvol_state_list); zv != NULL;
|
||
|
zv = list_next(&zvol_state_list, zv)) {
|
||
|
mutex_enter(&zv->zv_state_lock);
|
||
|
if (zv->zv_dev == dev) {
|
||
|
rw_exit(&zvol_state_lock);
|
||
|
return (zv);
|
||
|
}
|
||
|
mutex_exit(&zv->zv_state_lock);
|
||
|
}
|
||
|
rw_exit(&zvol_state_lock);
|
||
|
|
||
|
return (NULL);
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Find a zvol_state_t given the name and hash generated by zvol_name_hash.
|
||
|
* If found, return with zv_suspend_lock and zv_state_lock taken, otherwise,
|
||
|
* return (NULL) without the taking locks. The zv_suspend_lock is always taken
|
||
|
* before zv_state_lock. The mode argument indicates the mode (including none)
|
||
|
* for zv_suspend_lock to be taken.
|
||
|
*/
|
||
|
static zvol_state_t *
|
||
|
zvol_find_by_name_hash(const char *name, uint64_t hash, int mode)
|
||
|
{
|
||
|
zvol_state_t *zv;
|
||
|
struct hlist_node *p = NULL;
|
||
|
|
||
|
rw_enter(&zvol_state_lock, RW_READER);
|
||
|
hlist_for_each(p, ZVOL_HT_HEAD(hash)) {
|
||
|
zv = hlist_entry(p, zvol_state_t, zv_hlink);
|
||
|
mutex_enter(&zv->zv_state_lock);
|
||
|
if (zv->zv_hash == hash &&
|
||
|
strncmp(zv->zv_name, name, MAXNAMELEN) == 0) {
|
||
|
/*
|
||
|
* this is the right zvol, take the locks in the
|
||
|
* right order
|
||
|
*/
|
||
|
if (mode != RW_NONE &&
|
||
|
!rw_tryenter(&zv->zv_suspend_lock, mode)) {
|
||
|
mutex_exit(&zv->zv_state_lock);
|
||
|
rw_enter(&zv->zv_suspend_lock, mode);
|
||
|
mutex_enter(&zv->zv_state_lock);
|
||
|
/*
|
||
|
* zvol cannot be renamed as we continue
|
||
|
* to hold zvol_state_lock
|
||
|
*/
|
||
|
ASSERT(zv->zv_hash == hash &&
|
||
|
strncmp(zv->zv_name, name, MAXNAMELEN)
|
||
|
== 0);
|
||
|
}
|
||
|
rw_exit(&zvol_state_lock);
|
||
|
return (zv);
|
||
|
}
|
||
|
mutex_exit(&zv->zv_state_lock);
|
||
|
}
|
||
|
rw_exit(&zvol_state_lock);
|
||
|
|
||
|
return (NULL);
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Find a zvol_state_t given the name.
|
||
|
* If found, return with zv_suspend_lock and zv_state_lock taken, otherwise,
|
||
|
* return (NULL) without the taking locks. The zv_suspend_lock is always taken
|
||
|
* before zv_state_lock. The mode argument indicates the mode (including none)
|
||
|
* for zv_suspend_lock to be taken.
|
||
|
*/
|
||
|
static zvol_state_t *
|
||
|
zvol_find_by_name(const char *name, int mode)
|
||
|
{
|
||
|
return (zvol_find_by_name_hash(name, zvol_name_hash(name), mode));
|
||
|
}
|
||
|
|
||
|
|
||
|
/*
|
||
|
* Given a path, return TRUE if path is a ZVOL.
|
||
|
*/
|
||
|
boolean_t
|
||
|
zvol_is_zvol(const char *device)
|
||
|
{
|
||
|
struct block_device *bdev;
|
||
|
unsigned int major;
|
||
|
|
||
|
bdev = vdev_lookup_bdev(device);
|
||
|
if (IS_ERR(bdev))
|
||
|
return (B_FALSE);
|
||
|
|
||
|
major = MAJOR(bdev->bd_dev);
|
||
|
bdput(bdev);
|
||
|
|
||
|
if (major == zvol_major)
|
||
|
return (B_TRUE);
|
||
|
|
||
|
return (B_FALSE);
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* ZFS_IOC_CREATE callback handles dmu zvol and zap object creation.
|
||
|
*/
|
||
|
void
|
||
|
zvol_create_cb(objset_t *os, void *arg, cred_t *cr, dmu_tx_t *tx)
|
||
|
{
|
||
|
zfs_creat_t *zct = arg;
|
||
|
nvlist_t *nvprops = zct->zct_props;
|
||
|
int error;
|
||
|
uint64_t volblocksize, volsize;
|
||
|
|
||
|
VERIFY(nvlist_lookup_uint64(nvprops,
|
||
|
zfs_prop_to_name(ZFS_PROP_VOLSIZE), &volsize) == 0);
|
||
|
if (nvlist_lookup_uint64(nvprops,
|
||
|
zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), &volblocksize) != 0)
|
||
|
volblocksize = zfs_prop_default_numeric(ZFS_PROP_VOLBLOCKSIZE);
|
||
|
|
||
|
/*
|
||
|
* These properties must be removed from the list so the generic
|
||
|
* property setting step won't apply to them.
|
||
|
*/
|
||
|
VERIFY(nvlist_remove_all(nvprops,
|
||
|
zfs_prop_to_name(ZFS_PROP_VOLSIZE)) == 0);
|
||
|
(void) nvlist_remove_all(nvprops,
|
||
|
zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE));
|
||
|
|
||
|
error = dmu_object_claim(os, ZVOL_OBJ, DMU_OT_ZVOL, volblocksize,
|
||
|
DMU_OT_NONE, 0, tx);
|
||
|
ASSERT(error == 0);
|
||
|
|
||
|
error = zap_create_claim(os, ZVOL_ZAP_OBJ, DMU_OT_ZVOL_PROP,
|
||
|
DMU_OT_NONE, 0, tx);
|
||
|
ASSERT(error == 0);
|
||
|
|
||
|
error = zap_update(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize, tx);
|
||
|
ASSERT(error == 0);
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* ZFS_IOC_OBJSET_STATS entry point.
|
||
|
*/
|
||
|
int
|
||
|
zvol_get_stats(objset_t *os, nvlist_t *nv)
|
||
|
{
|
||
|
int error;
|
||
|
dmu_object_info_t *doi;
|
||
|
uint64_t val;
|
||
|
|
||
|
error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &val);
|
||
|
if (error)
|
||
|
return (SET_ERROR(error));
|
||
|
|
||
|
dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_VOLSIZE, val);
|
||
|
doi = kmem_alloc(sizeof (dmu_object_info_t), KM_SLEEP);
|
||
|
error = dmu_object_info(os, ZVOL_OBJ, doi);
|
||
|
|
||
|
if (error == 0) {
|
||
|
dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_VOLBLOCKSIZE,
|
||
|
doi->doi_data_block_size);
|
||
|
}
|
||
|
|
||
|
kmem_free(doi, sizeof (dmu_object_info_t));
|
||
|
|
||
|
return (SET_ERROR(error));
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Sanity check volume size.
|
||
|
*/
|
||
|
int
|
||
|
zvol_check_volsize(uint64_t volsize, uint64_t blocksize)
|
||
|
{
|
||
|
if (volsize == 0)
|
||
|
return (SET_ERROR(EINVAL));
|
||
|
|
||
|
if (volsize % blocksize != 0)
|
||
|
return (SET_ERROR(EINVAL));
|
||
|
|
||
|
#ifdef _ILP32
|
||
|
if (volsize - 1 > SPEC_MAXOFFSET_T)
|
||
|
return (SET_ERROR(EOVERFLOW));
|
||
|
#endif
|
||
|
return (0);
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Ensure the zap is flushed then inform the VFS of the capacity change.
|
||
|
*/
|
||
|
static int
|
||
|
zvol_update_volsize(uint64_t volsize, objset_t *os)
|
||
|
{
|
||
|
dmu_tx_t *tx;
|
||
|
int error;
|
||
|
uint64_t txg;
|
||
|
|
||
|
tx = dmu_tx_create(os);
|
||
|
dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL);
|
||
|
dmu_tx_mark_netfree(tx);
|
||
|
error = dmu_tx_assign(tx, TXG_WAIT);
|
||
|
if (error) {
|
||
|
dmu_tx_abort(tx);
|
||
|
return (SET_ERROR(error));
|
||
|
}
|
||
|
txg = dmu_tx_get_txg(tx);
|
||
|
|
||
|
error = zap_update(os, ZVOL_ZAP_OBJ, "size", 8, 1,
|
||
|
&volsize, tx);
|
||
|
dmu_tx_commit(tx);
|
||
|
|
||
|
txg_wait_synced(dmu_objset_pool(os), txg);
|
||
|
|
||
|
if (error == 0)
|
||
|
error = dmu_free_long_range(os,
|
||
|
ZVOL_OBJ, volsize, DMU_OBJECT_END);
|
||
|
|
||
|
return (error);
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Set ZFS_PROP_VOLSIZE set entry point. Note that modifying the volume
|
||
|
* size will result in a udev "change" event being generated.
|
||
|
*/
|
||
|
int
|
||
|
zvol_set_volsize(const char *name, uint64_t volsize)
|
||
|
{
|
||
|
objset_t *os = NULL;
|
||
|
struct gendisk *disk = NULL;
|
||
|
uint64_t readonly;
|
||
|
int error;
|
||
|
boolean_t owned = B_FALSE;
|
||
|
|
||
|
error = dsl_prop_get_integer(name,
|
||
|
zfs_prop_to_name(ZFS_PROP_READONLY), &readonly, NULL);
|
||
|
if (error != 0)
|
||
|
return (SET_ERROR(error));
|
||
|
if (readonly)
|
||
|
return (SET_ERROR(EROFS));
|
||
|
|
||
|
zvol_state_t *zv = zvol_find_by_name(name, RW_READER);
|
||
|
|
||
|
ASSERT(zv == NULL || (MUTEX_HELD(&zv->zv_state_lock) &&
|
||
|
RW_READ_HELD(&zv->zv_suspend_lock)));
|
||
|
|
||
|
if (zv == NULL || zv->zv_objset == NULL) {
|
||
|
if (zv != NULL)
|
||
|
rw_exit(&zv->zv_suspend_lock);
|
||
|
if ((error = dmu_objset_own(name, DMU_OST_ZVOL, B_FALSE, B_TRUE,
|
||
|
FTAG, &os)) != 0) {
|
||
|
if (zv != NULL)
|
||
|
mutex_exit(&zv->zv_state_lock);
|
||
|
return (SET_ERROR(error));
|
||
|
}
|
||
|
owned = B_TRUE;
|
||
|
if (zv != NULL)
|
||
|
zv->zv_objset = os;
|
||
|
} else {
|
||
|
os = zv->zv_objset;
|
||
|
}
|
||
|
|
||
|
dmu_object_info_t *doi = kmem_alloc(sizeof (*doi), KM_SLEEP);
|
||
|
|
||
|
if ((error = dmu_object_info(os, ZVOL_OBJ, doi)) ||
|
||
|
(error = zvol_check_volsize(volsize, doi->doi_data_block_size)))
|
||
|
goto out;
|
||
|
|
||
|
error = zvol_update_volsize(volsize, os);
|
||
|
if (error == 0 && zv != NULL) {
|
||
|
zv->zv_volsize = volsize;
|
||
|
zv->zv_changed = 1;
|
||
|
disk = zv->zv_disk;
|
||
|
}
|
||
|
out:
|
||
|
kmem_free(doi, sizeof (dmu_object_info_t));
|
||
|
|
||
|
if (owned) {
|
||
|
dmu_objset_disown(os, B_TRUE, FTAG);
|
||
|
if (zv != NULL)
|
||
|
zv->zv_objset = NULL;
|
||
|
} else {
|
||
|
rw_exit(&zv->zv_suspend_lock);
|
||
|
}
|
||
|
|
||
|
if (zv != NULL)
|
||
|
mutex_exit(&zv->zv_state_lock);
|
||
|
|
||
|
if (disk != NULL)
|
||
|
revalidate_disk(disk);
|
||
|
|
||
|
return (SET_ERROR(error));
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Sanity check volume block size.
|
||
|
*/
|
||
|
int
|
||
|
zvol_check_volblocksize(const char *name, uint64_t volblocksize)
|
||
|
{
|
||
|
/* Record sizes above 128k need the feature to be enabled */
|
||
|
if (volblocksize > SPA_OLD_MAXBLOCKSIZE) {
|
||
|
spa_t *spa;
|
||
|
int error;
|
||
|
|
||
|
if ((error = spa_open(name, &spa, FTAG)) != 0)
|
||
|
return (error);
|
||
|
|
||
|
if (!spa_feature_is_enabled(spa, SPA_FEATURE_LARGE_BLOCKS)) {
|
||
|
spa_close(spa, FTAG);
|
||
|
return (SET_ERROR(ENOTSUP));
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* We don't allow setting the property above 1MB,
|
||
|
* unless the tunable has been changed.
|
||
|
*/
|
||
|
if (volblocksize > zfs_max_recordsize)
|
||
|
return (SET_ERROR(EDOM));
|
||
|
|
||
|
spa_close(spa, FTAG);
|
||
|
}
|
||
|
|
||
|
if (volblocksize < SPA_MINBLOCKSIZE ||
|
||
|
volblocksize > SPA_MAXBLOCKSIZE ||
|
||
|
!ISP2(volblocksize))
|
||
|
return (SET_ERROR(EDOM));
|
||
|
|
||
|
return (0);
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Set ZFS_PROP_VOLBLOCKSIZE set entry point.
|
||
|
*/
|
||
|
int
|
||
|
zvol_set_volblocksize(const char *name, uint64_t volblocksize)
|
||
|
{
|
||
|
zvol_state_t *zv;
|
||
|
dmu_tx_t *tx;
|
||
|
int error;
|
||
|
|
||
|
zv = zvol_find_by_name(name, RW_READER);
|
||
|
|
||
|
if (zv == NULL)
|
||
|
return (SET_ERROR(ENXIO));
|
||
|
|
||
|
ASSERT(MUTEX_HELD(&zv->zv_state_lock));
|
||
|
ASSERT(RW_READ_HELD(&zv->zv_suspend_lock));
|
||
|
|
||
|
if (zv->zv_flags & ZVOL_RDONLY) {
|
||
|
mutex_exit(&zv->zv_state_lock);
|
||
|
rw_exit(&zv->zv_suspend_lock);
|
||
|
return (SET_ERROR(EROFS));
|
||
|
}
|
||
|
|
||
|
tx = dmu_tx_create(zv->zv_objset);
|
||
|
dmu_tx_hold_bonus(tx, ZVOL_OBJ);
|
||
|
error = dmu_tx_assign(tx, TXG_WAIT);
|
||
|
if (error) {
|
||
|
dmu_tx_abort(tx);
|
||
|
} else {
|
||
|
error = dmu_object_set_blocksize(zv->zv_objset, ZVOL_OBJ,
|
||
|
volblocksize, 0, tx);
|
||
|
if (error == ENOTSUP)
|
||
|
error = SET_ERROR(EBUSY);
|
||
|
dmu_tx_commit(tx);
|
||
|
if (error == 0)
|
||
|
zv->zv_volblocksize = volblocksize;
|
||
|
}
|
||
|
|
||
|
mutex_exit(&zv->zv_state_lock);
|
||
|
rw_exit(&zv->zv_suspend_lock);
|
||
|
|
||
|
return (SET_ERROR(error));
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Replay a TX_TRUNCATE ZIL transaction if asked. TX_TRUNCATE is how we
|
||
|
* implement DKIOCFREE/free-long-range.
|
||
|
*/
|
||
|
static int
|
||
|
zvol_replay_truncate(void *arg1, void *arg2, boolean_t byteswap)
|
||
|
{
|
||
|
zvol_state_t *zv = arg1;
|
||
|
lr_truncate_t *lr = arg2;
|
||
|
uint64_t offset, length;
|
||
|
|
||
|
if (byteswap)
|
||
|
byteswap_uint64_array(lr, sizeof (*lr));
|
||
|
|
||
|
offset = lr->lr_offset;
|
||
|
length = lr->lr_length;
|
||
|
|
||
|
return (dmu_free_long_range(zv->zv_objset, ZVOL_OBJ, offset, length));
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Replay a TX_WRITE ZIL transaction that didn't get committed
|
||
|
* after a system failure
|
||
|
*/
|
||
|
static int
|
||
|
zvol_replay_write(void *arg1, void *arg2, boolean_t byteswap)
|
||
|
{
|
||
|
zvol_state_t *zv = arg1;
|
||
|
lr_write_t *lr = arg2;
|
||
|
objset_t *os = zv->zv_objset;
|
||
|
char *data = (char *)(lr + 1); /* data follows lr_write_t */
|
||
|
uint64_t offset, length;
|
||
|
dmu_tx_t *tx;
|
||
|
int error;
|
||
|
|
||
|
if (byteswap)
|
||
|
byteswap_uint64_array(lr, sizeof (*lr));
|
||
|
|
||
|
offset = lr->lr_offset;
|
||
|
length = lr->lr_length;
|
||
|
|
||
|
/* If it's a dmu_sync() block, write the whole block */
|
||
|
if (lr->lr_common.lrc_reclen == sizeof (lr_write_t)) {
|
||
|
uint64_t blocksize = BP_GET_LSIZE(&lr->lr_blkptr);
|
||
|
if (length < blocksize) {
|
||
|
offset -= offset % blocksize;
|
||
|
length = blocksize;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
tx = dmu_tx_create(os);
|
||
|
dmu_tx_hold_write(tx, ZVOL_OBJ, offset, length);
|
||
|
error = dmu_tx_assign(tx, TXG_WAIT);
|
||
|
if (error) {
|
||
|
dmu_tx_abort(tx);
|
||
|
} else {
|
||
|
dmu_write(os, ZVOL_OBJ, offset, length, data, tx);
|
||
|
dmu_tx_commit(tx);
|
||
|
}
|
||
|
|
||
|
return (error);
|
||
|
}
|
||
|
|
||
|
static int
|
||
|
zvol_replay_err(void *arg1, void *arg2, boolean_t byteswap)
|
||
|
{
|
||
|
return (SET_ERROR(ENOTSUP));
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Callback vectors for replaying records.
|
||
|
* Only TX_WRITE and TX_TRUNCATE are needed for zvol.
|
||
|
*/
|
||
|
zil_replay_func_t *zvol_replay_vector[TX_MAX_TYPE] = {
|
||
|
zvol_replay_err, /* no such transaction type */
|
||
|
zvol_replay_err, /* TX_CREATE */
|
||
|
zvol_replay_err, /* TX_MKDIR */
|
||
|
zvol_replay_err, /* TX_MKXATTR */
|
||
|
zvol_replay_err, /* TX_SYMLINK */
|
||
|
zvol_replay_err, /* TX_REMOVE */
|
||
|
zvol_replay_err, /* TX_RMDIR */
|
||
|
zvol_replay_err, /* TX_LINK */
|
||
|
zvol_replay_err, /* TX_RENAME */
|
||
|
zvol_replay_write, /* TX_WRITE */
|
||
|
zvol_replay_truncate, /* TX_TRUNCATE */
|
||
|
zvol_replay_err, /* TX_SETATTR */
|
||
|
zvol_replay_err, /* TX_ACL */
|
||
|
zvol_replay_err, /* TX_CREATE_ATTR */
|
||
|
zvol_replay_err, /* TX_CREATE_ACL_ATTR */
|
||
|
zvol_replay_err, /* TX_MKDIR_ACL */
|
||
|
zvol_replay_err, /* TX_MKDIR_ATTR */
|
||
|
zvol_replay_err, /* TX_MKDIR_ACL_ATTR */
|
||
|
zvol_replay_err, /* TX_WRITE2 */
|
||
|
};
|
||
|
|
||
|
/*
|
||
|
* zvol_log_write() handles synchronous writes using TX_WRITE ZIL transactions.
|
||
|
*
|
||
|
* We store data in the log buffers if it's small enough.
|
||
|
* Otherwise we will later flush the data out via dmu_sync().
|
||
|
*/
|
||
|
ssize_t zvol_immediate_write_sz = 32768;
|
||
|
|
||
|
static void
|
||
|
zvol_log_write(zvol_state_t *zv, dmu_tx_t *tx, uint64_t offset,
|
||
|
uint64_t size, int sync)
|
||
|
{
|
||
|
uint32_t blocksize = zv->zv_volblocksize;
|
||
|
zilog_t *zilog = zv->zv_zilog;
|
||
|
itx_wr_state_t write_state;
|
||
|
|
||
|
if (zil_replaying(zilog, tx))
|
||
|
return;
|
||
|
|
||
|
if (zilog->zl_logbias == ZFS_LOGBIAS_THROUGHPUT)
|
||
|
write_state = WR_INDIRECT;
|
||
|
else if (!spa_has_slogs(zilog->zl_spa) &&
|
||
|
size >= blocksize && blocksize > zvol_immediate_write_sz)
|
||
|
write_state = WR_INDIRECT;
|
||
|
else if (sync)
|
||
|
write_state = WR_COPIED;
|
||
|
else
|
||
|
write_state = WR_NEED_COPY;
|
||
|
|
||
|
while (size) {
|
||
|
itx_t *itx;
|
||
|
lr_write_t *lr;
|
||
|
itx_wr_state_t wr_state = write_state;
|
||
|
ssize_t len = size;
|
||
|
|
||
|
if (wr_state == WR_COPIED && size > ZIL_MAX_COPIED_DATA)
|
||
|
wr_state = WR_NEED_COPY;
|
||
|
else if (wr_state == WR_INDIRECT)
|
||
|
len = MIN(blocksize - P2PHASE(offset, blocksize), size);
|
||
|
|
||
|
itx = zil_itx_create(TX_WRITE, sizeof (*lr) +
|
||
|
(wr_state == WR_COPIED ? len : 0));
|
||
|
lr = (lr_write_t *)&itx->itx_lr;
|
||
|
if (wr_state == WR_COPIED && dmu_read_by_dnode(zv->zv_dn,
|
||
|
offset, len, lr+1, DMU_READ_NO_PREFETCH) != 0) {
|
||
|
zil_itx_destroy(itx);
|
||
|
itx = zil_itx_create(TX_WRITE, sizeof (*lr));
|
||
|
lr = (lr_write_t *)&itx->itx_lr;
|
||
|
wr_state = WR_NEED_COPY;
|
||
|
}
|
||
|
|
||
|
itx->itx_wr_state = wr_state;
|
||
|
lr->lr_foid = ZVOL_OBJ;
|
||
|
lr->lr_offset = offset;
|
||
|
lr->lr_length = len;
|
||
|
lr->lr_blkoff = 0;
|
||
|
BP_ZERO(&lr->lr_blkptr);
|
||
|
|
||
|
itx->itx_private = zv;
|
||
|
itx->itx_sync = sync;
|
||
|
|
||
|
(void) zil_itx_assign(zilog, itx, tx);
|
||
|
|
||
|
offset += len;
|
||
|
size -= len;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
typedef struct zv_request {
|
||
|
zvol_state_t *zv;
|
||
|
struct bio *bio;
|
||
|
locked_range_t *lr;
|
||
|
} zv_request_t;
|
||
|
|
||
|
static void
|
||
|
uio_from_bio(uio_t *uio, struct bio *bio)
|
||
|
{
|
||
|
uio->uio_bvec = &bio->bi_io_vec[BIO_BI_IDX(bio)];
|
||
|
uio->uio_iovcnt = bio->bi_vcnt - BIO_BI_IDX(bio);
|
||
|
uio->uio_loffset = BIO_BI_SECTOR(bio) << 9;
|
||
|
uio->uio_segflg = UIO_BVEC;
|
||
|
uio->uio_limit = MAXOFFSET_T;
|
||
|
uio->uio_resid = BIO_BI_SIZE(bio);
|
||
|
uio->uio_skip = BIO_BI_SKIP(bio);
|
||
|
}
|
||
|
|
||
|
static void
|
||
|
zvol_write(void *arg)
|
||
|
{
|
||
|
int error = 0;
|
||
|
|
||
|
zv_request_t *zvr = arg;
|
||
|
struct bio *bio = zvr->bio;
|
||
|
uio_t uio = { { 0 }, 0 };
|
||
|
uio_from_bio(&uio, bio);
|
||
|
|
||
|
zvol_state_t *zv = zvr->zv;
|
||
|
ASSERT(zv && zv->zv_open_count > 0);
|
||
|
ASSERT(zv->zv_zilog != NULL);
|
||
|
|
||
|
ssize_t start_resid = uio.uio_resid;
|
||
|
unsigned long start_jif = jiffies;
|
||
|
blk_generic_start_io_acct(zv->zv_queue, WRITE, bio_sectors(bio),
|
||
|
&zv->zv_disk->part0);
|
||
|
|
||
|
boolean_t sync =
|
||
|
bio_is_fua(bio) || zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS;
|
||
|
|
||
|
uint64_t volsize = zv->zv_volsize;
|
||
|
while (uio.uio_resid > 0 && uio.uio_loffset < volsize) {
|
||
|
uint64_t bytes = MIN(uio.uio_resid, DMU_MAX_ACCESS >> 1);
|
||
|
uint64_t off = uio.uio_loffset;
|
||
|
dmu_tx_t *tx = dmu_tx_create(zv->zv_objset);
|
||
|
|
||
|
if (bytes > volsize - off) /* don't write past the end */
|
||
|
bytes = volsize - off;
|
||
|
|
||
|
dmu_tx_hold_write(tx, ZVOL_OBJ, off, bytes);
|
||
|
|
||
|
/* This will only fail for ENOSPC */
|
||
|
error = dmu_tx_assign(tx, TXG_WAIT);
|
||
|
if (error) {
|
||
|
dmu_tx_abort(tx);
|
||
|
break;
|
||
|
}
|
||
|
error = dmu_write_uio_dnode(zv->zv_dn, &uio, bytes, tx);
|
||
|
if (error == 0) {
|
||
|
zvol_log_write(zv, tx, off, bytes, sync);
|
||
|
}
|
||
|
dmu_tx_commit(tx);
|
||
|
|
||
|
if (error)
|
||
|
break;
|
||
|
}
|
||
|
rangelock_exit(zvr->lr);
|
||
|
|
||
|
int64_t nwritten = start_resid - uio.uio_resid;
|
||
|
dataset_kstats_update_write_kstats(&zv->zv_kstat, nwritten);
|
||
|
task_io_account_write(nwritten);
|
||
|
|
||
|
if (sync)
|
||
|
zil_commit(zv->zv_zilog, ZVOL_OBJ);
|
||
|
|
||
|
rw_exit(&zv->zv_suspend_lock);
|
||
|
blk_generic_end_io_acct(zv->zv_queue, WRITE, &zv->zv_disk->part0,
|
||
|
start_jif);
|
||
|
BIO_END_IO(bio, -error);
|
||
|
kmem_free(zvr, sizeof (zv_request_t));
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Log a DKIOCFREE/free-long-range to the ZIL with TX_TRUNCATE.
|
||
|
*/
|
||
|
static void
|
||
|
zvol_log_truncate(zvol_state_t *zv, dmu_tx_t *tx, uint64_t off, uint64_t len,
|
||
|
boolean_t sync)
|
||
|
{
|
||
|
itx_t *itx;
|
||
|
lr_truncate_t *lr;
|
||
|
zilog_t *zilog = zv->zv_zilog;
|
||
|
|
||
|
if (zil_replaying(zilog, tx))
|
||
|
return;
|
||
|
|
||
|
itx = zil_itx_create(TX_TRUNCATE, sizeof (*lr));
|
||
|
lr = (lr_truncate_t *)&itx->itx_lr;
|
||
|
lr->lr_foid = ZVOL_OBJ;
|
||
|
lr->lr_offset = off;
|
||
|
lr->lr_length = len;
|
||
|
|
||
|
itx->itx_sync = sync;
|
||
|
zil_itx_assign(zilog, itx, tx);
|
||
|
}
|
||
|
|
||
|
static void
|
||
|
zvol_discard(void *arg)
|
||
|
{
|
||
|
zv_request_t *zvr = arg;
|
||
|
struct bio *bio = zvr->bio;
|
||
|
zvol_state_t *zv = zvr->zv;
|
||
|
uint64_t start = BIO_BI_SECTOR(bio) << 9;
|
||
|
uint64_t size = BIO_BI_SIZE(bio);
|
||
|
uint64_t end = start + size;
|
||
|
boolean_t sync;
|
||
|
int error = 0;
|
||
|
dmu_tx_t *tx;
|
||
|
unsigned long start_jif;
|
||
|
|
||
|
ASSERT(zv && zv->zv_open_count > 0);
|
||
|
ASSERT(zv->zv_zilog != NULL);
|
||
|
|
||
|
start_jif = jiffies;
|
||
|
blk_generic_start_io_acct(zv->zv_queue, WRITE, bio_sectors(bio),
|
||
|
&zv->zv_disk->part0);
|
||
|
|
||
|
sync = bio_is_fua(bio) || zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS;
|
||
|
|
||
|
if (end > zv->zv_volsize) {
|
||
|
error = SET_ERROR(EIO);
|
||
|
goto unlock;
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Align the request to volume block boundaries when a secure erase is
|
||
|
* not required. This will prevent dnode_free_range() from zeroing out
|
||
|
* the unaligned parts which is slow (read-modify-write) and useless
|
||
|
* since we are not freeing any space by doing so.
|
||
|
*/
|
||
|
if (!bio_is_secure_erase(bio)) {
|
||
|
start = P2ROUNDUP(start, zv->zv_volblocksize);
|
||
|
end = P2ALIGN(end, zv->zv_volblocksize);
|
||
|
size = end - start;
|
||
|
}
|
||
|
|
||
|
if (start >= end)
|
||
|
goto unlock;
|
||
|
|
||
|
tx = dmu_tx_create(zv->zv_objset);
|
||
|
dmu_tx_mark_netfree(tx);
|
||
|
error = dmu_tx_assign(tx, TXG_WAIT);
|
||
|
if (error != 0) {
|
||
|
dmu_tx_abort(tx);
|
||
|
} else {
|
||
|
zvol_log_truncate(zv, tx, start, size, B_TRUE);
|
||
|
dmu_tx_commit(tx);
|
||
|
error = dmu_free_long_range(zv->zv_objset,
|
||
|
ZVOL_OBJ, start, size);
|
||
|
}
|
||
|
unlock:
|
||
|
rangelock_exit(zvr->lr);
|
||
|
|
||
|
if (error == 0 && sync)
|
||
|
zil_commit(zv->zv_zilog, ZVOL_OBJ);
|
||
|
|
||
|
rw_exit(&zv->zv_suspend_lock);
|
||
|
blk_generic_end_io_acct(zv->zv_queue, WRITE, &zv->zv_disk->part0,
|
||
|
start_jif);
|
||
|
BIO_END_IO(bio, -error);
|
||
|
kmem_free(zvr, sizeof (zv_request_t));
|
||
|
}
|
||
|
|
||
|
static void
|
||
|
zvol_read(void *arg)
|
||
|
{
|
||
|
int error = 0;
|
||
|
|
||
|
zv_request_t *zvr = arg;
|
||
|
struct bio *bio = zvr->bio;
|
||
|
uio_t uio = { { 0 }, 0 };
|
||
|
uio_from_bio(&uio, bio);
|
||
|
|
||
|
zvol_state_t *zv = zvr->zv;
|
||
|
ASSERT(zv && zv->zv_open_count > 0);
|
||
|
|
||
|
ssize_t start_resid = uio.uio_resid;
|
||
|
unsigned long start_jif = jiffies;
|
||
|
blk_generic_start_io_acct(zv->zv_queue, READ, bio_sectors(bio),
|
||
|
&zv->zv_disk->part0);
|
||
|
|
||
|
uint64_t volsize = zv->zv_volsize;
|
||
|
while (uio.uio_resid > 0 && uio.uio_loffset < volsize) {
|
||
|
uint64_t bytes = MIN(uio.uio_resid, DMU_MAX_ACCESS >> 1);
|
||
|
|
||
|
/* don't read past the end */
|
||
|
if (bytes > volsize - uio.uio_loffset)
|
||
|
bytes = volsize - uio.uio_loffset;
|
||
|
|
||
|
error = dmu_read_uio_dnode(zv->zv_dn, &uio, bytes);
|
||
|
if (error) {
|
||
|
/* convert checksum errors into IO errors */
|
||
|
if (error == ECKSUM)
|
||
|
error = SET_ERROR(EIO);
|
||
|
break;
|
||
|
}
|
||
|
}
|
||
|
rangelock_exit(zvr->lr);
|
||
|
|
||
|
int64_t nread = start_resid - uio.uio_resid;
|
||
|
dataset_kstats_update_read_kstats(&zv->zv_kstat, nread);
|
||
|
task_io_account_read(nread);
|
||
|
|
||
|
rw_exit(&zv->zv_suspend_lock);
|
||
|
blk_generic_end_io_acct(zv->zv_queue, READ, &zv->zv_disk->part0,
|
||
|
start_jif);
|
||
|
BIO_END_IO(bio, -error);
|
||
|
kmem_free(zvr, sizeof (zv_request_t));
|
||
|
}
|
||
|
|
||
|
/* ARGSUSED */
|
||
|
static void
|
||
|
zvol_get_done(zgd_t *zgd, int error)
|
||
|
{
|
||
|
if (zgd->zgd_db)
|
||
|
dmu_buf_rele(zgd->zgd_db, zgd);
|
||
|
|
||
|
rangelock_exit(zgd->zgd_lr);
|
||
|
|
||
|
kmem_free(zgd, sizeof (zgd_t));
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Get data to generate a TX_WRITE intent log record.
|
||
|
*/
|
||
|
static int
|
||
|
zvol_get_data(void *arg, lr_write_t *lr, char *buf, struct lwb *lwb, zio_t *zio)
|
||
|
{
|
||
|
zvol_state_t *zv = arg;
|
||
|
uint64_t offset = lr->lr_offset;
|
||
|
uint64_t size = lr->lr_length;
|
||
|
dmu_buf_t *db;
|
||
|
zgd_t *zgd;
|
||
|
int error;
|
||
|
|
||
|
ASSERT3P(lwb, !=, NULL);
|
||
|
ASSERT3P(zio, !=, NULL);
|
||
|
ASSERT3U(size, !=, 0);
|
||
|
|
||
|
zgd = (zgd_t *)kmem_zalloc(sizeof (zgd_t), KM_SLEEP);
|
||
|
zgd->zgd_lwb = lwb;
|
||
|
|
||
|
/*
|
||
|
* Write records come in two flavors: immediate and indirect.
|
||
|
* For small writes it's cheaper to store the data with the
|
||
|
* log record (immediate); for large writes it's cheaper to
|
||
|
* sync the data and get a pointer to it (indirect) so that
|
||
|
* we don't have to write the data twice.
|
||
|
*/
|
||
|
if (buf != NULL) { /* immediate write */
|
||
|
zgd->zgd_lr = rangelock_enter(&zv->zv_rangelock, offset, size,
|
||
|
RL_READER);
|
||
|
error = dmu_read_by_dnode(zv->zv_dn, offset, size, buf,
|
||
|
DMU_READ_NO_PREFETCH);
|
||
|
} else { /* indirect write */
|
||
|
/*
|
||
|
* Have to lock the whole block to ensure when it's written out
|
||
|
* and its checksum is being calculated that no one can change
|
||
|
* the data. Contrarily to zfs_get_data we need not re-check
|
||
|
* blocksize after we get the lock because it cannot be changed.
|
||
|
*/
|
||
|
size = zv->zv_volblocksize;
|
||
|
offset = P2ALIGN_TYPED(offset, size, uint64_t);
|
||
|
zgd->zgd_lr = rangelock_enter(&zv->zv_rangelock, offset, size,
|
||
|
RL_READER);
|
||
|
error = dmu_buf_hold_by_dnode(zv->zv_dn, offset, zgd, &db,
|
||
|
DMU_READ_NO_PREFETCH);
|
||
|
if (error == 0) {
|
||
|
blkptr_t *bp = &lr->lr_blkptr;
|
||
|
|
||
|
zgd->zgd_db = db;
|
||
|
zgd->zgd_bp = bp;
|
||
|
|
||
|
ASSERT(db != NULL);
|
||
|
ASSERT(db->db_offset == offset);
|
||
|
ASSERT(db->db_size == size);
|
||
|
|
||
|
error = dmu_sync(zio, lr->lr_common.lrc_txg,
|
||
|
zvol_get_done, zgd);
|
||
|
|
||
|
if (error == 0)
|
||
|
return (0);
|
||
|
}
|
||
|
}
|
||
|
|
||
|
zvol_get_done(zgd, error);
|
||
|
|
||
|
return (SET_ERROR(error));
|
||
|
}
|
||
|
|
||
|
static MAKE_REQUEST_FN_RET
|
||
|
zvol_request(struct request_queue *q, struct bio *bio)
|
||
|
{
|
||
|
zvol_state_t *zv = q->queuedata;
|
||
|
fstrans_cookie_t cookie = spl_fstrans_mark();
|
||
|
uint64_t offset = BIO_BI_SECTOR(bio) << 9;
|
||
|
uint64_t size = BIO_BI_SIZE(bio);
|
||
|
int rw = bio_data_dir(bio);
|
||
|
zv_request_t *zvr;
|
||
|
|
||
|
if (bio_has_data(bio) && offset + size > zv->zv_volsize) {
|
||
|
printk(KERN_INFO
|
||
|
"%s: bad access: offset=%llu, size=%lu\n",
|
||
|
zv->zv_disk->disk_name,
|
||
|
(long long unsigned)offset,
|
||
|
(long unsigned)size);
|
||
|
|
||
|
BIO_END_IO(bio, -SET_ERROR(EIO));
|
||
|
goto out;
|
||
|
}
|
||
|
|
||
|
if (rw == WRITE) {
|
||
|
boolean_t need_sync = B_FALSE;
|
||
|
|
||
|
if (unlikely(zv->zv_flags & ZVOL_RDONLY)) {
|
||
|
BIO_END_IO(bio, -SET_ERROR(EROFS));
|
||
|
goto out;
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* To be released in the I/O function. See the comment on
|
||
|
* rangelock_enter() below.
|
||
|
*/
|
||
|
rw_enter(&zv->zv_suspend_lock, RW_READER);
|
||
|
|
||
|
/*
|
||
|
* Open a ZIL if this is the first time we have written to this
|
||
|
* zvol. We protect zv->zv_zilog with zv_suspend_lock rather
|
||
|
* than zv_state_lock so that we don't need to acquire an
|
||
|
* additional lock in this path.
|
||
|
*/
|
||
|
if (zv->zv_zilog == NULL) {
|
||
|
rw_exit(&zv->zv_suspend_lock);
|
||
|
rw_enter(&zv->zv_suspend_lock, RW_WRITER);
|
||
|
if (zv->zv_zilog == NULL) {
|
||
|
zv->zv_zilog = zil_open(zv->zv_objset,
|
||
|
zvol_get_data);
|
||
|
zv->zv_flags |= ZVOL_WRITTEN_TO;
|
||
|
}
|
||
|
rw_downgrade(&zv->zv_suspend_lock);
|
||
|
}
|
||
|
|
||
|
/* bio marked as FLUSH need to flush before write */
|
||
|
if (bio_is_flush(bio))
|
||
|
zil_commit(zv->zv_zilog, ZVOL_OBJ);
|
||
|
|
||
|
/* Some requests are just for flush and nothing else. */
|
||
|
if (size == 0) {
|
||
|
rw_exit(&zv->zv_suspend_lock);
|
||
|
BIO_END_IO(bio, 0);
|
||
|
goto out;
|
||
|
}
|
||
|
|
||
|
zvr = kmem_alloc(sizeof (zv_request_t), KM_SLEEP);
|
||
|
zvr->zv = zv;
|
||
|
zvr->bio = bio;
|
||
|
|
||
|
/*
|
||
|
* To be released in the I/O function. Since the I/O functions
|
||
|
* are asynchronous, we take it here synchronously to make
|
||
|
* sure overlapped I/Os are properly ordered.
|
||
|
*/
|
||
|
zvr->lr = rangelock_enter(&zv->zv_rangelock, offset, size,
|
||
|
RL_WRITER);
|
||
|
/*
|
||
|
* Sync writes and discards execute zil_commit() which may need
|
||
|
* to take a RL_READER lock on the whole block being modified
|
||
|
* via its zillog->zl_get_data(): to avoid circular dependency
|
||
|
* issues with taskq threads execute these requests
|
||
|
* synchronously here in zvol_request().
|
||
|
*/
|
||
|
need_sync = bio_is_fua(bio) ||
|
||
|
zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS;
|
||
|
if (bio_is_discard(bio) || bio_is_secure_erase(bio)) {
|
||
|
if (zvol_request_sync || need_sync ||
|
||
|
taskq_dispatch(zvol_taskq, zvol_discard, zvr,
|
||
|
TQ_SLEEP) == TASKQID_INVALID)
|
||
|
zvol_discard(zvr);
|
||
|
} else {
|
||
|
if (zvol_request_sync || need_sync ||
|
||
|
taskq_dispatch(zvol_taskq, zvol_write, zvr,
|
||
|
TQ_SLEEP) == TASKQID_INVALID)
|
||
|
zvol_write(zvr);
|
||
|
}
|
||
|
} else {
|
||
|
/*
|
||
|
* The SCST driver, and possibly others, may issue READ I/Os
|
||
|
* with a length of zero bytes. These empty I/Os contain no
|
||
|
* data and require no additional handling.
|
||
|
*/
|
||
|
if (size == 0) {
|
||
|
BIO_END_IO(bio, 0);
|
||
|
goto out;
|
||
|
}
|
||
|
|
||
|
zvr = kmem_alloc(sizeof (zv_request_t), KM_SLEEP);
|
||
|
zvr->zv = zv;
|
||
|
zvr->bio = bio;
|
||
|
|
||
|
rw_enter(&zv->zv_suspend_lock, RW_READER);
|
||
|
|
||
|
zvr->lr = rangelock_enter(&zv->zv_rangelock, offset, size,
|
||
|
RL_READER);
|
||
|
if (zvol_request_sync || taskq_dispatch(zvol_taskq,
|
||
|
zvol_read, zvr, TQ_SLEEP) == TASKQID_INVALID)
|
||
|
zvol_read(zvr);
|
||
|
}
|
||
|
|
||
|
out:
|
||
|
spl_fstrans_unmark(cookie);
|
||
|
#ifdef HAVE_MAKE_REQUEST_FN_RET_INT
|
||
|
return (0);
|
||
|
#elif defined(HAVE_MAKE_REQUEST_FN_RET_QC)
|
||
|
return (BLK_QC_T_NONE);
|
||
|
#endif
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* The zvol_state_t's are inserted into zvol_state_list and zvol_htable.
|
||
|
*/
|
||
|
static void
|
||
|
zvol_insert(zvol_state_t *zv)
|
||
|
{
|
||
|
ASSERT(RW_WRITE_HELD(&zvol_state_lock));
|
||
|
ASSERT3U(MINOR(zv->zv_dev) & ZVOL_MINOR_MASK, ==, 0);
|
||
|
list_insert_head(&zvol_state_list, zv);
|
||
|
hlist_add_head(&zv->zv_hlink, ZVOL_HT_HEAD(zv->zv_hash));
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Simply remove the zvol from to list of zvols.
|
||
|
*/
|
||
|
static void
|
||
|
zvol_remove(zvol_state_t *zv)
|
||
|
{
|
||
|
ASSERT(RW_WRITE_HELD(&zvol_state_lock));
|
||
|
list_remove(&zvol_state_list, zv);
|
||
|
hlist_del(&zv->zv_hlink);
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Setup zv after we just own the zv->objset
|
||
|
*/
|
||
|
static int
|
||
|
zvol_setup_zv(zvol_state_t *zv)
|
||
|
{
|
||
|
uint64_t volsize;
|
||
|
int error;
|
||
|
uint64_t ro;
|
||
|
objset_t *os = zv->zv_objset;
|
||
|
|
||
|
ASSERT(MUTEX_HELD(&zv->zv_state_lock));
|
||
|
ASSERT(RW_LOCK_HELD(&zv->zv_suspend_lock));
|
||
|
|
||
|
zv->zv_zilog = NULL;
|
||
|
zv->zv_flags &= ~ZVOL_WRITTEN_TO;
|
||
|
|
||
|
error = dsl_prop_get_integer(zv->zv_name, "readonly", &ro, NULL);
|
||
|
if (error)
|
||
|
return (SET_ERROR(error));
|
||
|
|
||
|
error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize);
|
||
|
if (error)
|
||
|
return (SET_ERROR(error));
|
||
|
|
||
|
error = dnode_hold(os, ZVOL_OBJ, FTAG, &zv->zv_dn);
|
||
|
if (error)
|
||
|
return (SET_ERROR(error));
|
||
|
|
||
|
set_capacity(zv->zv_disk, volsize >> 9);
|
||
|
zv->zv_volsize = volsize;
|
||
|
|
||
|
if (ro || dmu_objset_is_snapshot(os) ||
|
||
|
!spa_writeable(dmu_objset_spa(os))) {
|
||
|
set_disk_ro(zv->zv_disk, 1);
|
||
|
zv->zv_flags |= ZVOL_RDONLY;
|
||
|
} else {
|
||
|
set_disk_ro(zv->zv_disk, 0);
|
||
|
zv->zv_flags &= ~ZVOL_RDONLY;
|
||
|
}
|
||
|
return (0);
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Shutdown every zv_objset related stuff except zv_objset itself.
|
||
|
* The is the reverse of zvol_setup_zv.
|
||
|
*/
|
||
|
static void
|
||
|
zvol_shutdown_zv(zvol_state_t *zv)
|
||
|
{
|
||
|
ASSERT(MUTEX_HELD(&zv->zv_state_lock) &&
|
||
|
RW_LOCK_HELD(&zv->zv_suspend_lock));
|
||
|
|
||
|
if (zv->zv_flags & ZVOL_WRITTEN_TO) {
|
||
|
ASSERT(zv->zv_zilog != NULL);
|
||
|
zil_close(zv->zv_zilog);
|
||
|
}
|
||
|
|
||
|
zv->zv_zilog = NULL;
|
||
|
|
||
|
dnode_rele(zv->zv_dn, FTAG);
|
||
|
zv->zv_dn = NULL;
|
||
|
|
||
|
/*
|
||
|
* Evict cached data. We must write out any dirty data before
|
||
|
* disowning the dataset.
|
||
|
*/
|
||
|
if (zv->zv_flags & ZVOL_WRITTEN_TO)
|
||
|
txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0);
|
||
|
(void) dmu_objset_evict_dbufs(zv->zv_objset);
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* return the proper tag for rollback and recv
|
||
|
*/
|
||
|
void *
|
||
|
zvol_tag(zvol_state_t *zv)
|
||
|
{
|
||
|
ASSERT(RW_WRITE_HELD(&zv->zv_suspend_lock));
|
||
|
return (zv->zv_open_count > 0 ? zv : NULL);
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Suspend the zvol for recv and rollback.
|
||
|
*/
|
||
|
zvol_state_t *
|
||
|
zvol_suspend(const char *name)
|
||
|
{
|
||
|
zvol_state_t *zv;
|
||
|
|
||
|
zv = zvol_find_by_name(name, RW_WRITER);
|
||
|
|
||
|
if (zv == NULL)
|
||
|
return (NULL);
|
||
|
|
||
|
/* block all I/O, release in zvol_resume. */
|
||
|
ASSERT(MUTEX_HELD(&zv->zv_state_lock));
|
||
|
ASSERT(RW_WRITE_HELD(&zv->zv_suspend_lock));
|
||
|
|
||
|
atomic_inc(&zv->zv_suspend_ref);
|
||
|
|
||
|
if (zv->zv_open_count > 0)
|
||
|
zvol_shutdown_zv(zv);
|
||
|
|
||
|
/*
|
||
|
* do not hold zv_state_lock across suspend/resume to
|
||
|
* avoid locking up zvol lookups
|
||
|
*/
|
||
|
mutex_exit(&zv->zv_state_lock);
|
||
|
|
||
|
/* zv_suspend_lock is released in zvol_resume() */
|
||
|
return (zv);
|
||
|
}
|
||
|
|
||
|
int
|
||
|
zvol_resume(zvol_state_t *zv)
|
||
|
{
|
||
|
int error = 0;
|
||
|
|
||
|
ASSERT(RW_WRITE_HELD(&zv->zv_suspend_lock));
|
||
|
|
||
|
mutex_enter(&zv->zv_state_lock);
|
||
|
|
||
|
if (zv->zv_open_count > 0) {
|
||
|
VERIFY0(dmu_objset_hold(zv->zv_name, zv, &zv->zv_objset));
|
||
|
VERIFY3P(zv->zv_objset->os_dsl_dataset->ds_owner, ==, zv);
|
||
|
VERIFY(dsl_dataset_long_held(zv->zv_objset->os_dsl_dataset));
|
||
|
dmu_objset_rele(zv->zv_objset, zv);
|
||
|
|
||
|
error = zvol_setup_zv(zv);
|
||
|
}
|
||
|
|
||
|
mutex_exit(&zv->zv_state_lock);
|
||
|
|
||
|
rw_exit(&zv->zv_suspend_lock);
|
||
|
/*
|
||
|
* We need this because we don't hold zvol_state_lock while releasing
|
||
|
* zv_suspend_lock. zvol_remove_minors_impl thus cannot check
|
||
|
* zv_suspend_lock to determine it is safe to free because rwlock is
|
||
|
* not inherent atomic.
|
||
|
*/
|
||
|
atomic_dec(&zv->zv_suspend_ref);
|
||
|
|
||
|
return (SET_ERROR(error));
|
||
|
}
|
||
|
|
||
|
static int
|
||
|
zvol_first_open(zvol_state_t *zv, boolean_t readonly)
|
||
|
{
|
||
|
objset_t *os;
|
||
|
int error, locked = 0;
|
||
|
boolean_t ro;
|
||
|
|
||
|
ASSERT(RW_READ_HELD(&zv->zv_suspend_lock));
|
||
|
ASSERT(MUTEX_HELD(&zv->zv_state_lock));
|
||
|
|
||
|
/*
|
||
|
* In all other cases the spa_namespace_lock is taken before the
|
||
|
* bdev->bd_mutex lock. But in this case the Linux __blkdev_get()
|
||
|
* function calls fops->open() with the bdev->bd_mutex lock held.
|
||
|
* This deadlock can be easily observed with zvols used as vdevs.
|
||
|
*
|
||
|
* To avoid a potential lock inversion deadlock we preemptively
|
||
|
* try to take the spa_namespace_lock(). Normally it will not
|
||
|
* be contended and this is safe because spa_open_common() handles
|
||
|
* the case where the caller already holds the spa_namespace_lock.
|
||
|
*
|
||
|
* When it is contended we risk a lock inversion if we were to
|
||
|
* block waiting for the lock. Luckily, the __blkdev_get()
|
||
|
* function allows us to return -ERESTARTSYS which will result in
|
||
|
* bdev->bd_mutex being dropped, reacquired, and fops->open() being
|
||
|
* called again. This process can be repeated safely until both
|
||
|
* locks are acquired.
|
||
|
*/
|
||
|
if (!mutex_owned(&spa_namespace_lock)) {
|
||
|
locked = mutex_tryenter(&spa_namespace_lock);
|
||
|
if (!locked)
|
||
|
return (-SET_ERROR(ERESTARTSYS));
|
||
|
}
|
||
|
|
||
|
ro = (readonly || (strchr(zv->zv_name, '@') != NULL));
|
||
|
error = dmu_objset_own(zv->zv_name, DMU_OST_ZVOL, ro, B_TRUE, zv, &os);
|
||
|
if (error)
|
||
|
goto out_mutex;
|
||
|
|
||
|
zv->zv_objset = os;
|
||
|
|
||
|
error = zvol_setup_zv(zv);
|
||
|
|
||
|
if (error) {
|
||
|
dmu_objset_disown(os, 1, zv);
|
||
|
zv->zv_objset = NULL;
|
||
|
}
|
||
|
|
||
|
out_mutex:
|
||
|
if (locked)
|
||
|
mutex_exit(&spa_namespace_lock);
|
||
|
return (SET_ERROR(-error));
|
||
|
}
|
||
|
|
||
|
static void
|
||
|
zvol_last_close(zvol_state_t *zv)
|
||
|
{
|
||
|
ASSERT(RW_READ_HELD(&zv->zv_suspend_lock));
|
||
|
ASSERT(MUTEX_HELD(&zv->zv_state_lock));
|
||
|
|
||
|
zvol_shutdown_zv(zv);
|
||
|
|
||
|
dmu_objset_disown(zv->zv_objset, 1, zv);
|
||
|
zv->zv_objset = NULL;
|
||
|
}
|
||
|
|
||
|
static int
|
||
|
zvol_open(struct block_device *bdev, fmode_t flag)
|
||
|
{
|
||
|
zvol_state_t *zv;
|
||
|
int error = 0;
|
||
|
boolean_t drop_suspend = B_TRUE;
|
||
|
|
||
|
rw_enter(&zvol_state_lock, RW_READER);
|
||
|
/*
|
||
|
* Obtain a copy of private_data under the zvol_state_lock to make
|
||
|
* sure that either the result of zvol free code path setting
|
||
|
* bdev->bd_disk->private_data to NULL is observed, or zvol_free()
|
||
|
* is not called on this zv because of the positive zv_open_count.
|
||
|
*/
|
||
|
zv = bdev->bd_disk->private_data;
|
||
|
if (zv == NULL) {
|
||
|
rw_exit(&zvol_state_lock);
|
||
|
return (SET_ERROR(-ENXIO));
|
||
|
}
|
||
|
|
||
|
mutex_enter(&zv->zv_state_lock);
|
||
|
/*
|
||
|
* make sure zvol is not suspended during first open
|
||
|
* (hold zv_suspend_lock) and respect proper lock acquisition
|
||
|
* ordering - zv_suspend_lock before zv_state_lock
|
||
|
*/
|
||
|
if (zv->zv_open_count == 0) {
|
||
|
if (!rw_tryenter(&zv->zv_suspend_lock, RW_READER)) {
|
||
|
mutex_exit(&zv->zv_state_lock);
|
||
|
rw_enter(&zv->zv_suspend_lock, RW_READER);
|
||
|
mutex_enter(&zv->zv_state_lock);
|
||
|
/* check to see if zv_suspend_lock is needed */
|
||
|
if (zv->zv_open_count != 0) {
|
||
|
rw_exit(&zv->zv_suspend_lock);
|
||
|
drop_suspend = B_FALSE;
|
||
|
}
|
||
|
}
|
||
|
} else {
|
||
|
drop_suspend = B_FALSE;
|
||
|
}
|
||
|
rw_exit(&zvol_state_lock);
|
||
|
|
||
|
ASSERT(MUTEX_HELD(&zv->zv_state_lock));
|
||
|
ASSERT(zv->zv_open_count != 0 || RW_READ_HELD(&zv->zv_suspend_lock));
|
||
|
|
||
|
if (zv->zv_open_count == 0) {
|
||
|
error = zvol_first_open(zv, !(flag & FMODE_WRITE));
|
||
|
if (error)
|
||
|
goto out_mutex;
|
||
|
}
|
||
|
|
||
|
if ((flag & FMODE_WRITE) && (zv->zv_flags & ZVOL_RDONLY)) {
|
||
|
error = -EROFS;
|
||
|
goto out_open_count;
|
||
|
}
|
||
|
|
||
|
zv->zv_open_count++;
|
||
|
|
||
|
mutex_exit(&zv->zv_state_lock);
|
||
|
if (drop_suspend)
|
||
|
rw_exit(&zv->zv_suspend_lock);
|
||
|
|
||
|
check_disk_change(bdev);
|
||
|
|
||
|
return (0);
|
||
|
|
||
|
out_open_count:
|
||
|
if (zv->zv_open_count == 0)
|
||
|
zvol_last_close(zv);
|
||
|
|
||
|
out_mutex:
|
||
|
mutex_exit(&zv->zv_state_lock);
|
||
|
if (drop_suspend)
|
||
|
rw_exit(&zv->zv_suspend_lock);
|
||
|
if (error == -ERESTARTSYS)
|
||
|
schedule();
|
||
|
|
||
|
return (SET_ERROR(error));
|
||
|
}
|
||
|
|
||
|
#ifdef HAVE_BLOCK_DEVICE_OPERATIONS_RELEASE_VOID
|
||
|
static void
|
||
|
#else
|
||
|
static int
|
||
|
#endif
|
||
|
zvol_release(struct gendisk *disk, fmode_t mode)
|
||
|
{
|
||
|
zvol_state_t *zv;
|
||
|
boolean_t drop_suspend = B_TRUE;
|
||
|
|
||
|
rw_enter(&zvol_state_lock, RW_READER);
|
||
|
zv = disk->private_data;
|
||
|
|
||
|
mutex_enter(&zv->zv_state_lock);
|
||
|
ASSERT(zv->zv_open_count > 0);
|
||
|
/*
|
||
|
* make sure zvol is not suspended during last close
|
||
|
* (hold zv_suspend_lock) and respect proper lock acquisition
|
||
|
* ordering - zv_suspend_lock before zv_state_lock
|
||
|
*/
|
||
|
if (zv->zv_open_count == 1) {
|
||
|
if (!rw_tryenter(&zv->zv_suspend_lock, RW_READER)) {
|
||
|
mutex_exit(&zv->zv_state_lock);
|
||
|
rw_enter(&zv->zv_suspend_lock, RW_READER);
|
||
|
mutex_enter(&zv->zv_state_lock);
|
||
|
/* check to see if zv_suspend_lock is needed */
|
||
|
if (zv->zv_open_count != 1) {
|
||
|
rw_exit(&zv->zv_suspend_lock);
|
||
|
drop_suspend = B_FALSE;
|
||
|
}
|
||
|
}
|
||
|
} else {
|
||
|
drop_suspend = B_FALSE;
|
||
|
}
|
||
|
rw_exit(&zvol_state_lock);
|
||
|
|
||
|
ASSERT(MUTEX_HELD(&zv->zv_state_lock));
|
||
|
ASSERT(zv->zv_open_count != 1 || RW_READ_HELD(&zv->zv_suspend_lock));
|
||
|
|
||
|
zv->zv_open_count--;
|
||
|
if (zv->zv_open_count == 0)
|
||
|
zvol_last_close(zv);
|
||
|
|
||
|
mutex_exit(&zv->zv_state_lock);
|
||
|
|
||
|
if (drop_suspend)
|
||
|
rw_exit(&zv->zv_suspend_lock);
|
||
|
|
||
|
#ifndef HAVE_BLOCK_DEVICE_OPERATIONS_RELEASE_VOID
|
||
|
return (0);
|
||
|
#endif
|
||
|
}
|
||
|
|
||
|
static int
|
||
|
zvol_ioctl(struct block_device *bdev, fmode_t mode,
|
||
|
unsigned int cmd, unsigned long arg)
|
||
|
{
|
||
|
zvol_state_t *zv = bdev->bd_disk->private_data;
|
||
|
int error = 0;
|
||
|
|
||
|
ASSERT3U(zv->zv_open_count, >, 0);
|
||
|
|
||
|
switch (cmd) {
|
||
|
case BLKFLSBUF:
|
||
|
fsync_bdev(bdev);
|
||
|
invalidate_bdev(bdev);
|
||
|
rw_enter(&zv->zv_suspend_lock, RW_READER);
|
||
|
|
||
|
if (!(zv->zv_flags & ZVOL_RDONLY))
|
||
|
txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0);
|
||
|
|
||
|
rw_exit(&zv->zv_suspend_lock);
|
||
|
break;
|
||
|
|
||
|
case BLKZNAME:
|
||
|
mutex_enter(&zv->zv_state_lock);
|
||
|
error = copy_to_user((void *)arg, zv->zv_name, MAXNAMELEN);
|
||
|
mutex_exit(&zv->zv_state_lock);
|
||
|
break;
|
||
|
|
||
|
default:
|
||
|
error = -ENOTTY;
|
||
|
break;
|
||
|
}
|
||
|
|
||
|
return (SET_ERROR(error));
|
||
|
}
|
||
|
|
||
|
#ifdef CONFIG_COMPAT
|
||
|
static int
|
||
|
zvol_compat_ioctl(struct block_device *bdev, fmode_t mode,
|
||
|
unsigned cmd, unsigned long arg)
|
||
|
{
|
||
|
return (zvol_ioctl(bdev, mode, cmd, arg));
|
||
|
}
|
||
|
#else
|
||
|
#define zvol_compat_ioctl NULL
|
||
|
#endif
|
||
|
|
||
|
/*
|
||
|
* Linux 2.6.38 preferred interface.
|
||
|
*/
|
||
|
#ifdef HAVE_BLOCK_DEVICE_OPERATIONS_CHECK_EVENTS
|
||
|
static unsigned int
|
||
|
zvol_check_events(struct gendisk *disk, unsigned int clearing)
|
||
|
{
|
||
|
unsigned int mask = 0;
|
||
|
|
||
|
rw_enter(&zvol_state_lock, RW_READER);
|
||
|
|
||
|
zvol_state_t *zv = disk->private_data;
|
||
|
if (zv != NULL) {
|
||
|
mutex_enter(&zv->zv_state_lock);
|
||
|
mask = zv->zv_changed ? DISK_EVENT_MEDIA_CHANGE : 0;
|
||
|
zv->zv_changed = 0;
|
||
|
mutex_exit(&zv->zv_state_lock);
|
||
|
}
|
||
|
|
||
|
rw_exit(&zvol_state_lock);
|
||
|
|
||
|
return (mask);
|
||
|
}
|
||
|
#else
|
||
|
static int zvol_media_changed(struct gendisk *disk)
|
||
|
{
|
||
|
int changed = 0;
|
||
|
|
||
|
rw_enter(&zvol_state_lock, RW_READER);
|
||
|
|
||
|
zvol_state_t *zv = disk->private_data;
|
||
|
if (zv != NULL) {
|
||
|
mutex_enter(&zv->zv_state_lock);
|
||
|
changed = zv->zv_changed;
|
||
|
zv->zv_changed = 0;
|
||
|
mutex_exit(&zv->zv_state_lock);
|
||
|
}
|
||
|
|
||
|
rw_exit(&zvol_state_lock);
|
||
|
|
||
|
return (changed);
|
||
|
}
|
||
|
#endif
|
||
|
|
||
|
static int zvol_revalidate_disk(struct gendisk *disk)
|
||
|
{
|
||
|
rw_enter(&zvol_state_lock, RW_READER);
|
||
|
|
||
|
zvol_state_t *zv = disk->private_data;
|
||
|
if (zv != NULL) {
|
||
|
mutex_enter(&zv->zv_state_lock);
|
||
|
set_capacity(zv->zv_disk, zv->zv_volsize >> SECTOR_BITS);
|
||
|
mutex_exit(&zv->zv_state_lock);
|
||
|
}
|
||
|
|
||
|
rw_exit(&zvol_state_lock);
|
||
|
|
||
|
return (0);
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Provide a simple virtual geometry for legacy compatibility. For devices
|
||
|
* smaller than 1 MiB a small head and sector count is used to allow very
|
||
|
* tiny devices. For devices over 1 Mib a standard head and sector count
|
||
|
* is used to keep the cylinders count reasonable.
|
||
|
*/
|
||
|
static int
|
||
|
zvol_getgeo(struct block_device *bdev, struct hd_geometry *geo)
|
||
|
{
|
||
|
zvol_state_t *zv = bdev->bd_disk->private_data;
|
||
|
sector_t sectors;
|
||
|
|
||
|
ASSERT3U(zv->zv_open_count, >, 0);
|
||
|
|
||
|
sectors = get_capacity(zv->zv_disk);
|
||
|
|
||
|
if (sectors > 2048) {
|
||
|
geo->heads = 16;
|
||
|
geo->sectors = 63;
|
||
|
} else {
|
||
|
geo->heads = 2;
|
||
|
geo->sectors = 4;
|
||
|
}
|
||
|
|
||
|
geo->start = 0;
|
||
|
geo->cylinders = sectors / (geo->heads * geo->sectors);
|
||
|
|
||
|
return (0);
|
||
|
}
|
||
|
|
||
|
static struct kobject *
|
||
|
zvol_probe(dev_t dev, int *part, void *arg)
|
||
|
{
|
||
|
zvol_state_t *zv;
|
||
|
struct kobject *kobj;
|
||
|
|
||
|
zv = zvol_find_by_dev(dev);
|
||
|
kobj = zv ? get_disk_and_module(zv->zv_disk) : NULL;
|
||
|
ASSERT(zv == NULL || MUTEX_HELD(&zv->zv_state_lock));
|
||
|
if (zv)
|
||
|
mutex_exit(&zv->zv_state_lock);
|
||
|
|
||
|
return (kobj);
|
||
|
}
|
||
|
|
||
|
static struct block_device_operations zvol_ops = {
|
||
|
.open = zvol_open,
|
||
|
.release = zvol_release,
|
||
|
.ioctl = zvol_ioctl,
|
||
|
.compat_ioctl = zvol_compat_ioctl,
|
||
|
#ifdef HAVE_BLOCK_DEVICE_OPERATIONS_CHECK_EVENTS
|
||
|
.check_events = zvol_check_events,
|
||
|
#else
|
||
|
.media_changed = zvol_media_changed,
|
||
|
#endif
|
||
|
.revalidate_disk = zvol_revalidate_disk,
|
||
|
.getgeo = zvol_getgeo,
|
||
|
.owner = THIS_MODULE,
|
||
|
};
|
||
|
|
||
|
/*
|
||
|
* Allocate memory for a new zvol_state_t and setup the required
|
||
|
* request queue and generic disk structures for the block device.
|
||
|
*/
|
||
|
static zvol_state_t *
|
||
|
zvol_alloc(dev_t dev, const char *name)
|
||
|
{
|
||
|
zvol_state_t *zv;
|
||
|
uint64_t volmode;
|
||
|
|
||
|
if (dsl_prop_get_integer(name, "volmode", &volmode, NULL) != 0)
|
||
|
return (NULL);
|
||
|
|
||
|
if (volmode == ZFS_VOLMODE_DEFAULT)
|
||
|
volmode = zvol_volmode;
|
||
|
|
||
|
if (volmode == ZFS_VOLMODE_NONE)
|
||
|
return (NULL);
|
||
|
|
||
|
zv = kmem_zalloc(sizeof (zvol_state_t), KM_SLEEP);
|
||
|
|
||
|
list_link_init(&zv->zv_next);
|
||
|
|
||
|
mutex_init(&zv->zv_state_lock, NULL, MUTEX_DEFAULT, NULL);
|
||
|
|
||
|
zv->zv_queue = blk_alloc_queue(GFP_ATOMIC);
|
||
|
if (zv->zv_queue == NULL)
|
||
|
goto out_kmem;
|
||
|
|
||
|
blk_queue_make_request(zv->zv_queue, zvol_request);
|
||
|
blk_queue_set_write_cache(zv->zv_queue, B_TRUE, B_TRUE);
|
||
|
|
||
|
/* Limit read-ahead to a single page to prevent over-prefetching. */
|
||
|
blk_queue_set_read_ahead(zv->zv_queue, 1);
|
||
|
|
||
|
/* Disable write merging in favor of the ZIO pipeline. */
|
||
|
blk_queue_flag_set(QUEUE_FLAG_NOMERGES, zv->zv_queue);
|
||
|
|
||
|
zv->zv_disk = alloc_disk(ZVOL_MINORS);
|
||
|
if (zv->zv_disk == NULL)
|
||
|
goto out_queue;
|
||
|
|
||
|
zv->zv_queue->queuedata = zv;
|
||
|
zv->zv_dev = dev;
|
||
|
zv->zv_open_count = 0;
|
||
|
strlcpy(zv->zv_name, name, MAXNAMELEN);
|
||
|
|
||
|
rangelock_init(&zv->zv_rangelock, NULL, NULL);
|
||
|
rw_init(&zv->zv_suspend_lock, NULL, RW_DEFAULT, NULL);
|
||
|
|
||
|
zv->zv_disk->major = zvol_major;
|
||
|
#ifdef HAVE_BLOCK_DEVICE_OPERATIONS_CHECK_EVENTS
|
||
|
zv->zv_disk->events = DISK_EVENT_MEDIA_CHANGE;
|
||
|
#endif
|
||
|
|
||
|
if (volmode == ZFS_VOLMODE_DEV) {
|
||
|
/*
|
||
|
* ZFS_VOLMODE_DEV disable partitioning on ZVOL devices: set
|
||
|
* gendisk->minors = 1 as noted in include/linux/genhd.h.
|
||
|
* Also disable extended partition numbers (GENHD_FL_EXT_DEVT)
|
||
|
* and suppresses partition scanning (GENHD_FL_NO_PART_SCAN)
|
||
|
* setting gendisk->flags accordingly.
|
||
|
*/
|
||
|
zv->zv_disk->minors = 1;
|
||
|
#if defined(GENHD_FL_EXT_DEVT)
|
||
|
zv->zv_disk->flags &= ~GENHD_FL_EXT_DEVT;
|
||
|
#endif
|
||
|
#if defined(GENHD_FL_NO_PART_SCAN)
|
||
|
zv->zv_disk->flags |= GENHD_FL_NO_PART_SCAN;
|
||
|
#endif
|
||
|
}
|
||
|
zv->zv_disk->first_minor = (dev & MINORMASK);
|
||
|
zv->zv_disk->fops = &zvol_ops;
|
||
|
zv->zv_disk->private_data = zv;
|
||
|
zv->zv_disk->queue = zv->zv_queue;
|
||
|
snprintf(zv->zv_disk->disk_name, DISK_NAME_LEN, "%s%d",
|
||
|
ZVOL_DEV_NAME, (dev & MINORMASK));
|
||
|
|
||
|
return (zv);
|
||
|
|
||
|
out_queue:
|
||
|
blk_cleanup_queue(zv->zv_queue);
|
||
|
out_kmem:
|
||
|
kmem_free(zv, sizeof (zvol_state_t));
|
||
|
|
||
|
return (NULL);
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Cleanup then free a zvol_state_t which was created by zvol_alloc().
|
||
|
* At this time, the structure is not opened by anyone, is taken off
|
||
|
* the zvol_state_list, and has its private data set to NULL.
|
||
|
* The zvol_state_lock is dropped.
|
||
|
*/
|
||
|
static void
|
||
|
zvol_free(void *arg)
|
||
|
{
|
||
|
zvol_state_t *zv = arg;
|
||
|
|
||
|
ASSERT(!RW_LOCK_HELD(&zv->zv_suspend_lock));
|
||
|
ASSERT(!MUTEX_HELD(&zv->zv_state_lock));
|
||
|
ASSERT(zv->zv_open_count == 0);
|
||
|
ASSERT(zv->zv_disk->private_data == NULL);
|
||
|
|
||
|
rw_destroy(&zv->zv_suspend_lock);
|
||
|
rangelock_fini(&zv->zv_rangelock);
|
||
|
|
||
|
del_gendisk(zv->zv_disk);
|
||
|
blk_cleanup_queue(zv->zv_queue);
|
||
|
put_disk(zv->zv_disk);
|
||
|
|
||
|
ida_simple_remove(&zvol_ida, MINOR(zv->zv_dev) >> ZVOL_MINOR_BITS);
|
||
|
|
||
|
mutex_destroy(&zv->zv_state_lock);
|
||
|
dataset_kstats_destroy(&zv->zv_kstat);
|
||
|
|
||
|
kmem_free(zv, sizeof (zvol_state_t));
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Create a block device minor node and setup the linkage between it
|
||
|
* and the specified volume. Once this function returns the block
|
||
|
* device is live and ready for use.
|
||
|
*/
|
||
|
static int
|
||
|
zvol_create_minor_impl(const char *name)
|
||
|
{
|
||
|
zvol_state_t *zv;
|
||
|
objset_t *os;
|
||
|
dmu_object_info_t *doi;
|
||
|
uint64_t volsize;
|
||
|
uint64_t len;
|
||
|
unsigned minor = 0;
|
||
|
int error = 0;
|
||
|
int idx;
|
||
|
uint64_t hash = zvol_name_hash(name);
|
||
|
|
||
|
if (zvol_inhibit_dev)
|
||
|
return (0);
|
||
|
|
||
|
idx = ida_simple_get(&zvol_ida, 0, 0, kmem_flags_convert(KM_SLEEP));
|
||
|
if (idx < 0)
|
||
|
return (SET_ERROR(-idx));
|
||
|
minor = idx << ZVOL_MINOR_BITS;
|
||
|
|
||
|
zv = zvol_find_by_name_hash(name, hash, RW_NONE);
|
||
|
if (zv) {
|
||
|
ASSERT(MUTEX_HELD(&zv->zv_state_lock));
|
||
|
mutex_exit(&zv->zv_state_lock);
|
||
|
ida_simple_remove(&zvol_ida, idx);
|
||
|
return (SET_ERROR(EEXIST));
|
||
|
}
|
||
|
|
||
|
doi = kmem_alloc(sizeof (dmu_object_info_t), KM_SLEEP);
|
||
|
|
||
|
error = dmu_objset_own(name, DMU_OST_ZVOL, B_TRUE, B_TRUE, FTAG, &os);
|
||
|
if (error)
|
||
|
goto out_doi;
|
||
|
|
||
|
error = dmu_object_info(os, ZVOL_OBJ, doi);
|
||
|
if (error)
|
||
|
goto out_dmu_objset_disown;
|
||
|
|
||
|
error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize);
|
||
|
if (error)
|
||
|
goto out_dmu_objset_disown;
|
||
|
|
||
|
zv = zvol_alloc(MKDEV(zvol_major, minor), name);
|
||
|
if (zv == NULL) {
|
||
|
error = SET_ERROR(EAGAIN);
|
||
|
goto out_dmu_objset_disown;
|
||
|
}
|
||
|
zv->zv_hash = hash;
|
||
|
|
||
|
if (dmu_objset_is_snapshot(os))
|
||
|
zv->zv_flags |= ZVOL_RDONLY;
|
||
|
|
||
|
zv->zv_volblocksize = doi->doi_data_block_size;
|
||
|
zv->zv_volsize = volsize;
|
||
|
zv->zv_objset = os;
|
||
|
|
||
|
set_capacity(zv->zv_disk, zv->zv_volsize >> 9);
|
||
|
|
||
|
blk_queue_max_hw_sectors(zv->zv_queue, (DMU_MAX_ACCESS / 4) >> 9);
|
||
|
blk_queue_max_segments(zv->zv_queue, UINT16_MAX);
|
||
|
blk_queue_max_segment_size(zv->zv_queue, UINT_MAX);
|
||
|
blk_queue_physical_block_size(zv->zv_queue, zv->zv_volblocksize);
|
||
|
blk_queue_io_opt(zv->zv_queue, zv->zv_volblocksize);
|
||
|
blk_queue_max_discard_sectors(zv->zv_queue,
|
||
|
(zvol_max_discard_blocks * zv->zv_volblocksize) >> 9);
|
||
|
blk_queue_discard_granularity(zv->zv_queue, zv->zv_volblocksize);
|
||
|
blk_queue_flag_set(QUEUE_FLAG_DISCARD, zv->zv_queue);
|
||
|
#ifdef QUEUE_FLAG_NONROT
|
||
|
blk_queue_flag_set(QUEUE_FLAG_NONROT, zv->zv_queue);
|
||
|
#endif
|
||
|
#ifdef QUEUE_FLAG_ADD_RANDOM
|
||
|
blk_queue_flag_clear(QUEUE_FLAG_ADD_RANDOM, zv->zv_queue);
|
||
|
#endif
|
||
|
/* This flag was introduced in kernel version 4.12. */
|
||
|
#ifdef QUEUE_FLAG_SCSI_PASSTHROUGH
|
||
|
blk_queue_flag_set(QUEUE_FLAG_SCSI_PASSTHROUGH, zv->zv_queue);
|
||
|
#endif
|
||
|
|
||
|
if (spa_writeable(dmu_objset_spa(os))) {
|
||
|
if (zil_replay_disable)
|
||
|
zil_destroy(dmu_objset_zil(os), B_FALSE);
|
||
|
else
|
||
|
zil_replay(os, zv, zvol_replay_vector);
|
||
|
}
|
||
|
ASSERT3P(zv->zv_kstat.dk_kstats, ==, NULL);
|
||
|
dataset_kstats_create(&zv->zv_kstat, zv->zv_objset);
|
||
|
|
||
|
/*
|
||
|
* When udev detects the addition of the device it will immediately
|
||
|
* invoke blkid(8) to determine the type of content on the device.
|
||
|
* Prefetching the blocks commonly scanned by blkid(8) will speed
|
||
|
* up this process.
|
||
|
*/
|
||
|
len = MIN(MAX(zvol_prefetch_bytes, 0), SPA_MAXBLOCKSIZE);
|
||
|
if (len > 0) {
|
||
|
dmu_prefetch(os, ZVOL_OBJ, 0, 0, len, ZIO_PRIORITY_SYNC_READ);
|
||
|
dmu_prefetch(os, ZVOL_OBJ, 0, volsize - len, len,
|
||
|
ZIO_PRIORITY_SYNC_READ);
|
||
|
}
|
||
|
|
||
|
zv->zv_objset = NULL;
|
||
|
out_dmu_objset_disown:
|
||
|
dmu_objset_disown(os, B_TRUE, FTAG);
|
||
|
out_doi:
|
||
|
kmem_free(doi, sizeof (dmu_object_info_t));
|
||
|
|
||
|
if (error == 0) {
|
||
|
rw_enter(&zvol_state_lock, RW_WRITER);
|
||
|
zvol_insert(zv);
|
||
|
rw_exit(&zvol_state_lock);
|
||
|
add_disk(zv->zv_disk);
|
||
|
} else {
|
||
|
ida_simple_remove(&zvol_ida, idx);
|
||
|
}
|
||
|
|
||
|
return (SET_ERROR(error));
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Rename a block device minor mode for the specified volume.
|
||
|
*/
|
||
|
static void
|
||
|
zvol_rename_minor(zvol_state_t *zv, const char *newname)
|
||
|
{
|
||
|
int readonly = get_disk_ro(zv->zv_disk);
|
||
|
|
||
|
ASSERT(RW_LOCK_HELD(&zvol_state_lock));
|
||
|
ASSERT(MUTEX_HELD(&zv->zv_state_lock));
|
||
|
|
||
|
strlcpy(zv->zv_name, newname, sizeof (zv->zv_name));
|
||
|
|
||
|
/* move to new hashtable entry */
|
||
|
zv->zv_hash = zvol_name_hash(zv->zv_name);
|
||
|
hlist_del(&zv->zv_hlink);
|
||
|
hlist_add_head(&zv->zv_hlink, ZVOL_HT_HEAD(zv->zv_hash));
|
||
|
|
||
|
/*
|
||
|
* The block device's read-only state is briefly changed causing
|
||
|
* a KOBJ_CHANGE uevent to be issued. This ensures udev detects
|
||
|
* the name change and fixes the symlinks. This does not change
|
||
|
* ZVOL_RDONLY in zv->zv_flags so the actual read-only state never
|
||
|
* changes. This would normally be done using kobject_uevent() but
|
||
|
* that is a GPL-only symbol which is why we need this workaround.
|
||
|
*/
|
||
|
set_disk_ro(zv->zv_disk, !readonly);
|
||
|
set_disk_ro(zv->zv_disk, readonly);
|
||
|
}
|
||
|
|
||
|
typedef struct minors_job {
|
||
|
list_t *list;
|
||
|
list_node_t link;
|
||
|
/* input */
|
||
|
char *name;
|
||
|
/* output */
|
||
|
int error;
|
||
|
} minors_job_t;
|
||
|
|
||
|
/*
|
||
|
* Prefetch zvol dnodes for the minors_job
|
||
|
*/
|
||
|
static void
|
||
|
zvol_prefetch_minors_impl(void *arg)
|
||
|
{
|
||
|
minors_job_t *job = arg;
|
||
|
char *dsname = job->name;
|
||
|
objset_t *os = NULL;
|
||
|
|
||
|
job->error = dmu_objset_own(dsname, DMU_OST_ZVOL, B_TRUE, B_TRUE,
|
||
|
FTAG, &os);
|
||
|
if (job->error == 0) {
|
||
|
dmu_prefetch(os, ZVOL_OBJ, 0, 0, 0, ZIO_PRIORITY_SYNC_READ);
|
||
|
dmu_objset_disown(os, B_TRUE, FTAG);
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Mask errors to continue dmu_objset_find() traversal
|
||
|
*/
|
||
|
static int
|
||
|
zvol_create_snap_minor_cb(const char *dsname, void *arg)
|
||
|
{
|
||
|
minors_job_t *j = arg;
|
||
|
list_t *minors_list = j->list;
|
||
|
const char *name = j->name;
|
||
|
|
||
|
ASSERT0(MUTEX_HELD(&spa_namespace_lock));
|
||
|
|
||
|
/* skip the designated dataset */
|
||
|
if (name && strcmp(dsname, name) == 0)
|
||
|
return (0);
|
||
|
|
||
|
/* at this point, the dsname should name a snapshot */
|
||
|
if (strchr(dsname, '@') == 0) {
|
||
|
dprintf("zvol_create_snap_minor_cb(): "
|
||
|
"%s is not a shapshot name\n", dsname);
|
||
|
} else {
|
||
|
minors_job_t *job;
|
||
|
char *n = strdup(dsname);
|
||
|
if (n == NULL)
|
||
|
return (0);
|
||
|
|
||
|
job = kmem_alloc(sizeof (minors_job_t), KM_SLEEP);
|
||
|
job->name = n;
|
||
|
job->list = minors_list;
|
||
|
job->error = 0;
|
||
|
list_insert_tail(minors_list, job);
|
||
|
/* don't care if dispatch fails, because job->error is 0 */
|
||
|
taskq_dispatch(system_taskq, zvol_prefetch_minors_impl, job,
|
||
|
TQ_SLEEP);
|
||
|
}
|
||
|
|
||
|
return (0);
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Mask errors to continue dmu_objset_find() traversal
|
||
|
*/
|
||
|
static int
|
||
|
zvol_create_minors_cb(const char *dsname, void *arg)
|
||
|
{
|
||
|
uint64_t snapdev;
|
||
|
int error;
|
||
|
list_t *minors_list = arg;
|
||
|
|
||
|
ASSERT0(MUTEX_HELD(&spa_namespace_lock));
|
||
|
|
||
|
error = dsl_prop_get_integer(dsname, "snapdev", &snapdev, NULL);
|
||
|
if (error)
|
||
|
return (0);
|
||
|
|
||
|
/*
|
||
|
* Given the name and the 'snapdev' property, create device minor nodes
|
||
|
* with the linkages to zvols/snapshots as needed.
|
||
|
* If the name represents a zvol, create a minor node for the zvol, then
|
||
|
* check if its snapshots are 'visible', and if so, iterate over the
|
||
|
* snapshots and create device minor nodes for those.
|
||
|
*/
|
||
|
if (strchr(dsname, '@') == 0) {
|
||
|
minors_job_t *job;
|
||
|
char *n = strdup(dsname);
|
||
|
if (n == NULL)
|
||
|
return (0);
|
||
|
|
||
|
job = kmem_alloc(sizeof (minors_job_t), KM_SLEEP);
|
||
|
job->name = n;
|
||
|
job->list = minors_list;
|
||
|
job->error = 0;
|
||
|
list_insert_tail(minors_list, job);
|
||
|
/* don't care if dispatch fails, because job->error is 0 */
|
||
|
taskq_dispatch(system_taskq, zvol_prefetch_minors_impl, job,
|
||
|
TQ_SLEEP);
|
||
|
|
||
|
if (snapdev == ZFS_SNAPDEV_VISIBLE) {
|
||
|
/*
|
||
|
* traverse snapshots only, do not traverse children,
|
||
|
* and skip the 'dsname'
|
||
|
*/
|
||
|
error = dmu_objset_find((char *)dsname,
|
||
|
zvol_create_snap_minor_cb, (void *)job,
|
||
|
DS_FIND_SNAPSHOTS);
|
||
|
}
|
||
|
} else {
|
||
|
dprintf("zvol_create_minors_cb(): %s is not a zvol name\n",
|
||
|
dsname);
|
||
|
}
|
||
|
|
||
|
return (0);
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Create minors for the specified dataset, including children and snapshots.
|
||
|
* Pay attention to the 'snapdev' property and iterate over the snapshots
|
||
|
* only if they are 'visible'. This approach allows one to assure that the
|
||
|
* snapshot metadata is read from disk only if it is needed.
|
||
|
*
|
||
|
* The name can represent a dataset to be recursively scanned for zvols and
|
||
|
* their snapshots, or a single zvol snapshot. If the name represents a
|
||
|
* dataset, the scan is performed in two nested stages:
|
||
|
* - scan the dataset for zvols, and
|
||
|
* - for each zvol, create a minor node, then check if the zvol's snapshots
|
||
|
* are 'visible', and only then iterate over the snapshots if needed
|
||
|
*
|
||
|
* If the name represents a snapshot, a check is performed if the snapshot is
|
||
|
* 'visible' (which also verifies that the parent is a zvol), and if so,
|
||
|
* a minor node for that snapshot is created.
|
||
|
*/
|
||
|
static int
|
||
|
zvol_create_minors_impl(const char *name)
|
||
|
{
|
||
|
int error = 0;
|
||
|
fstrans_cookie_t cookie;
|
||
|
char *atp, *parent;
|
||
|
list_t minors_list;
|
||
|
minors_job_t *job;
|
||
|
|
||
|
if (zvol_inhibit_dev)
|
||
|
return (0);
|
||
|
|
||
|
/*
|
||
|
* This is the list for prefetch jobs. Whenever we found a match
|
||
|
* during dmu_objset_find, we insert a minors_job to the list and do
|
||
|
* taskq_dispatch to parallel prefetch zvol dnodes. Note we don't need
|
||
|
* any lock because all list operation is done on the current thread.
|
||
|
*
|
||
|
* We will use this list to do zvol_create_minor_impl after prefetch
|
||
|
* so we don't have to traverse using dmu_objset_find again.
|
||
|
*/
|
||
|
list_create(&minors_list, sizeof (minors_job_t),
|
||
|
offsetof(minors_job_t, link));
|
||
|
|
||
|
parent = kmem_alloc(MAXPATHLEN, KM_SLEEP);
|
||
|
(void) strlcpy(parent, name, MAXPATHLEN);
|
||
|
|
||
|
if ((atp = strrchr(parent, '@')) != NULL) {
|
||
|
uint64_t snapdev;
|
||
|
|
||
|
*atp = '\0';
|
||
|
error = dsl_prop_get_integer(parent, "snapdev",
|
||
|
&snapdev, NULL);
|
||
|
|
||
|
if (error == 0 && snapdev == ZFS_SNAPDEV_VISIBLE)
|
||
|
error = zvol_create_minor_impl(name);
|
||
|
} else {
|
||
|
cookie = spl_fstrans_mark();
|
||
|
error = dmu_objset_find(parent, zvol_create_minors_cb,
|
||
|
&minors_list, DS_FIND_CHILDREN);
|
||
|
spl_fstrans_unmark(cookie);
|
||
|
}
|
||
|
|
||
|
kmem_free(parent, MAXPATHLEN);
|
||
|
taskq_wait_outstanding(system_taskq, 0);
|
||
|
|
||
|
/*
|
||
|
* Prefetch is completed, we can do zvol_create_minor_impl
|
||
|
* sequentially.
|
||
|
*/
|
||
|
while ((job = list_head(&minors_list)) != NULL) {
|
||
|
list_remove(&minors_list, job);
|
||
|
if (!job->error)
|
||
|
zvol_create_minor_impl(job->name);
|
||
|
strfree(job->name);
|
||
|
kmem_free(job, sizeof (minors_job_t));
|
||
|
}
|
||
|
|
||
|
list_destroy(&minors_list);
|
||
|
|
||
|
return (SET_ERROR(error));
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Remove minors for specified dataset including children and snapshots.
|
||
|
*/
|
||
|
static void
|
||
|
zvol_remove_minors_impl(const char *name)
|
||
|
{
|
||
|
zvol_state_t *zv, *zv_next;
|
||
|
int namelen = ((name) ? strlen(name) : 0);
|
||
|
taskqid_t t, tid = TASKQID_INVALID;
|
||
|
list_t free_list;
|
||
|
|
||
|
if (zvol_inhibit_dev)
|
||
|
return;
|
||
|
|
||
|
list_create(&free_list, sizeof (zvol_state_t),
|
||
|
offsetof(zvol_state_t, zv_next));
|
||
|
|
||
|
rw_enter(&zvol_state_lock, RW_WRITER);
|
||
|
|
||
|
for (zv = list_head(&zvol_state_list); zv != NULL; zv = zv_next) {
|
||
|
zv_next = list_next(&zvol_state_list, zv);
|
||
|
|
||
|
mutex_enter(&zv->zv_state_lock);
|
||
|
if (name == NULL || strcmp(zv->zv_name, name) == 0 ||
|
||
|
(strncmp(zv->zv_name, name, namelen) == 0 &&
|
||
|
(zv->zv_name[namelen] == '/' ||
|
||
|
zv->zv_name[namelen] == '@'))) {
|
||
|
/*
|
||
|
* By holding zv_state_lock here, we guarantee that no
|
||
|
* one is currently using this zv
|
||
|
*/
|
||
|
|
||
|
/* If in use, leave alone */
|
||
|
if (zv->zv_open_count > 0 ||
|
||
|
atomic_read(&zv->zv_suspend_ref)) {
|
||
|
mutex_exit(&zv->zv_state_lock);
|
||
|
continue;
|
||
|
}
|
||
|
|
||
|
zvol_remove(zv);
|
||
|
|
||
|
/*
|
||
|
* Cleared while holding zvol_state_lock as a writer
|
||
|
* which will prevent zvol_open() from opening it.
|
||
|
*/
|
||
|
zv->zv_disk->private_data = NULL;
|
||
|
|
||
|
/* Drop zv_state_lock before zvol_free() */
|
||
|
mutex_exit(&zv->zv_state_lock);
|
||
|
|
||
|
/* Try parallel zv_free, if failed do it in place */
|
||
|
t = taskq_dispatch(system_taskq, zvol_free, zv,
|
||
|
TQ_SLEEP);
|
||
|
if (t == TASKQID_INVALID)
|
||
|
list_insert_head(&free_list, zv);
|
||
|
else
|
||
|
tid = t;
|
||
|
} else {
|
||
|
mutex_exit(&zv->zv_state_lock);
|
||
|
}
|
||
|
}
|
||
|
rw_exit(&zvol_state_lock);
|
||
|
|
||
|
/* Drop zvol_state_lock before calling zvol_free() */
|
||
|
while ((zv = list_head(&free_list)) != NULL) {
|
||
|
list_remove(&free_list, zv);
|
||
|
zvol_free(zv);
|
||
|
}
|
||
|
|
||
|
if (tid != TASKQID_INVALID)
|
||
|
taskq_wait_outstanding(system_taskq, tid);
|
||
|
}
|
||
|
|
||
|
/* Remove minor for this specific volume only */
|
||
|
static void
|
||
|
zvol_remove_minor_impl(const char *name)
|
||
|
{
|
||
|
zvol_state_t *zv = NULL, *zv_next;
|
||
|
|
||
|
if (zvol_inhibit_dev)
|
||
|
return;
|
||
|
|
||
|
rw_enter(&zvol_state_lock, RW_WRITER);
|
||
|
|
||
|
for (zv = list_head(&zvol_state_list); zv != NULL; zv = zv_next) {
|
||
|
zv_next = list_next(&zvol_state_list, zv);
|
||
|
|
||
|
mutex_enter(&zv->zv_state_lock);
|
||
|
if (strcmp(zv->zv_name, name) == 0) {
|
||
|
/*
|
||
|
* By holding zv_state_lock here, we guarantee that no
|
||
|
* one is currently using this zv
|
||
|
*/
|
||
|
|
||
|
/* If in use, leave alone */
|
||
|
if (zv->zv_open_count > 0 ||
|
||
|
atomic_read(&zv->zv_suspend_ref)) {
|
||
|
mutex_exit(&zv->zv_state_lock);
|
||
|
continue;
|
||
|
}
|
||
|
zvol_remove(zv);
|
||
|
|
||
|
/*
|
||
|
* Cleared while holding zvol_state_lock as a writer
|
||
|
* which will prevent zvol_open() from opening it.
|
||
|
*/
|
||
|
zv->zv_disk->private_data = NULL;
|
||
|
|
||
|
mutex_exit(&zv->zv_state_lock);
|
||
|
break;
|
||
|
} else {
|
||
|
mutex_exit(&zv->zv_state_lock);
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/* Drop zvol_state_lock before calling zvol_free() */
|
||
|
rw_exit(&zvol_state_lock);
|
||
|
|
||
|
if (zv != NULL)
|
||
|
zvol_free(zv);
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Rename minors for specified dataset including children and snapshots.
|
||
|
*/
|
||
|
static void
|
||
|
zvol_rename_minors_impl(const char *oldname, const char *newname)
|
||
|
{
|
||
|
zvol_state_t *zv, *zv_next;
|
||
|
int oldnamelen, newnamelen;
|
||
|
|
||
|
if (zvol_inhibit_dev)
|
||
|
return;
|
||
|
|
||
|
oldnamelen = strlen(oldname);
|
||
|
newnamelen = strlen(newname);
|
||
|
|
||
|
rw_enter(&zvol_state_lock, RW_READER);
|
||
|
|
||
|
for (zv = list_head(&zvol_state_list); zv != NULL; zv = zv_next) {
|
||
|
zv_next = list_next(&zvol_state_list, zv);
|
||
|
|
||
|
mutex_enter(&zv->zv_state_lock);
|
||
|
|
||
|
if (strcmp(zv->zv_name, oldname) == 0) {
|
||
|
zvol_rename_minor(zv, newname);
|
||
|
} else if (strncmp(zv->zv_name, oldname, oldnamelen) == 0 &&
|
||
|
(zv->zv_name[oldnamelen] == '/' ||
|
||
|
zv->zv_name[oldnamelen] == '@')) {
|
||
|
char *name = kmem_asprintf("%s%c%s", newname,
|
||
|
zv->zv_name[oldnamelen],
|
||
|
zv->zv_name + oldnamelen + 1);
|
||
|
zvol_rename_minor(zv, name);
|
||
|
strfree(name);
|
||
|
}
|
||
|
|
||
|
mutex_exit(&zv->zv_state_lock);
|
||
|
}
|
||
|
|
||
|
rw_exit(&zvol_state_lock);
|
||
|
}
|
||
|
|
||
|
typedef struct zvol_snapdev_cb_arg {
|
||
|
uint64_t snapdev;
|
||
|
} zvol_snapdev_cb_arg_t;
|
||
|
|
||
|
static int
|
||
|
zvol_set_snapdev_cb(const char *dsname, void *param)
|
||
|
{
|
||
|
zvol_snapdev_cb_arg_t *arg = param;
|
||
|
|
||
|
if (strchr(dsname, '@') == NULL)
|
||
|
return (0);
|
||
|
|
||
|
switch (arg->snapdev) {
|
||
|
case ZFS_SNAPDEV_VISIBLE:
|
||
|
(void) zvol_create_minor_impl(dsname);
|
||
|
break;
|
||
|
case ZFS_SNAPDEV_HIDDEN:
|
||
|
(void) zvol_remove_minor_impl(dsname);
|
||
|
break;
|
||
|
}
|
||
|
|
||
|
return (0);
|
||
|
}
|
||
|
|
||
|
static void
|
||
|
zvol_set_snapdev_impl(char *name, uint64_t snapdev)
|
||
|
{
|
||
|
zvol_snapdev_cb_arg_t arg = {snapdev};
|
||
|
fstrans_cookie_t cookie = spl_fstrans_mark();
|
||
|
/*
|
||
|
* The zvol_set_snapdev_sync() sets snapdev appropriately
|
||
|
* in the dataset hierarchy. Here, we only scan snapshots.
|
||
|
*/
|
||
|
dmu_objset_find(name, zvol_set_snapdev_cb, &arg, DS_FIND_SNAPSHOTS);
|
||
|
spl_fstrans_unmark(cookie);
|
||
|
}
|
||
|
|
||
|
typedef struct zvol_volmode_cb_arg {
|
||
|
uint64_t volmode;
|
||
|
} zvol_volmode_cb_arg_t;
|
||
|
|
||
|
static void
|
||
|
zvol_set_volmode_impl(char *name, uint64_t volmode)
|
||
|
{
|
||
|
fstrans_cookie_t cookie = spl_fstrans_mark();
|
||
|
|
||
|
if (strchr(name, '@') != NULL)
|
||
|
return;
|
||
|
|
||
|
/*
|
||
|
* It's unfortunate we need to remove minors before we create new ones:
|
||
|
* this is necessary because our backing gendisk (zvol_state->zv_disk)
|
||
|
* coule be different when we set, for instance, volmode from "geom"
|
||
|
* to "dev" (or vice versa).
|
||
|
* A possible optimization is to modify our consumers so we don't get
|
||
|
* called when "volmode" does not change.
|
||
|
*/
|
||
|
switch (volmode) {
|
||
|
case ZFS_VOLMODE_NONE:
|
||
|
(void) zvol_remove_minor_impl(name);
|
||
|
break;
|
||
|
case ZFS_VOLMODE_GEOM:
|
||
|
case ZFS_VOLMODE_DEV:
|
||
|
(void) zvol_remove_minor_impl(name);
|
||
|
(void) zvol_create_minor_impl(name);
|
||
|
break;
|
||
|
case ZFS_VOLMODE_DEFAULT:
|
||
|
(void) zvol_remove_minor_impl(name);
|
||
|
if (zvol_volmode == ZFS_VOLMODE_NONE)
|
||
|
break;
|
||
|
else /* if zvol_volmode is invalid defaults to "geom" */
|
||
|
(void) zvol_create_minor_impl(name);
|
||
|
break;
|
||
|
}
|
||
|
|
||
|
spl_fstrans_unmark(cookie);
|
||
|
}
|
||
|
|
||
|
static zvol_task_t *
|
||
|
zvol_task_alloc(zvol_async_op_t op, const char *name1, const char *name2,
|
||
|
uint64_t value)
|
||
|
{
|
||
|
zvol_task_t *task;
|
||
|
char *delim;
|
||
|
|
||
|
/* Never allow tasks on hidden names. */
|
||
|
if (name1[0] == '$')
|
||
|
return (NULL);
|
||
|
|
||
|
task = kmem_zalloc(sizeof (zvol_task_t), KM_SLEEP);
|
||
|
task->op = op;
|
||
|
task->value = value;
|
||
|
delim = strchr(name1, '/');
|
||
|
strlcpy(task->pool, name1, delim ? (delim - name1 + 1) : MAXNAMELEN);
|
||
|
|
||
|
strlcpy(task->name1, name1, MAXNAMELEN);
|
||
|
if (name2 != NULL)
|
||
|
strlcpy(task->name2, name2, MAXNAMELEN);
|
||
|
|
||
|
return (task);
|
||
|
}
|
||
|
|
||
|
static void
|
||
|
zvol_task_free(zvol_task_t *task)
|
||
|
{
|
||
|
kmem_free(task, sizeof (zvol_task_t));
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* The worker thread function performed asynchronously.
|
||
|
*/
|
||
|
static void
|
||
|
zvol_task_cb(void *param)
|
||
|
{
|
||
|
zvol_task_t *task = (zvol_task_t *)param;
|
||
|
|
||
|
switch (task->op) {
|
||
|
case ZVOL_ASYNC_CREATE_MINORS:
|
||
|
(void) zvol_create_minors_impl(task->name1);
|
||
|
break;
|
||
|
case ZVOL_ASYNC_REMOVE_MINORS:
|
||
|
zvol_remove_minors_impl(task->name1);
|
||
|
break;
|
||
|
case ZVOL_ASYNC_RENAME_MINORS:
|
||
|
zvol_rename_minors_impl(task->name1, task->name2);
|
||
|
break;
|
||
|
case ZVOL_ASYNC_SET_SNAPDEV:
|
||
|
zvol_set_snapdev_impl(task->name1, task->value);
|
||
|
break;
|
||
|
case ZVOL_ASYNC_SET_VOLMODE:
|
||
|
zvol_set_volmode_impl(task->name1, task->value);
|
||
|
break;
|
||
|
default:
|
||
|
VERIFY(0);
|
||
|
break;
|
||
|
}
|
||
|
|
||
|
zvol_task_free(task);
|
||
|
}
|
||
|
|
||
|
typedef struct zvol_set_prop_int_arg {
|
||
|
const char *zsda_name;
|
||
|
uint64_t zsda_value;
|
||
|
zprop_source_t zsda_source;
|
||
|
dmu_tx_t *zsda_tx;
|
||
|
} zvol_set_prop_int_arg_t;
|
||
|
|
||
|
/*
|
||
|
* Sanity check the dataset for safe use by the sync task. No additional
|
||
|
* conditions are imposed.
|
||
|
*/
|
||
|
static int
|
||
|
zvol_set_snapdev_check(void *arg, dmu_tx_t *tx)
|
||
|
{
|
||
|
zvol_set_prop_int_arg_t *zsda = arg;
|
||
|
dsl_pool_t *dp = dmu_tx_pool(tx);
|
||
|
dsl_dir_t *dd;
|
||
|
int error;
|
||
|
|
||
|
error = dsl_dir_hold(dp, zsda->zsda_name, FTAG, &dd, NULL);
|
||
|
if (error != 0)
|
||
|
return (error);
|
||
|
|
||
|
dsl_dir_rele(dd, FTAG);
|
||
|
|
||
|
return (error);
|
||
|
}
|
||
|
|
||
|
/* ARGSUSED */
|
||
|
static int
|
||
|
zvol_set_snapdev_sync_cb(dsl_pool_t *dp, dsl_dataset_t *ds, void *arg)
|
||
|
{
|
||
|
char dsname[MAXNAMELEN];
|
||
|
zvol_task_t *task;
|
||
|
uint64_t snapdev;
|
||
|
|
||
|
dsl_dataset_name(ds, dsname);
|
||
|
if (dsl_prop_get_int_ds(ds, "snapdev", &snapdev) != 0)
|
||
|
return (0);
|
||
|
task = zvol_task_alloc(ZVOL_ASYNC_SET_SNAPDEV, dsname, NULL, snapdev);
|
||
|
if (task == NULL)
|
||
|
return (0);
|
||
|
|
||
|
(void) taskq_dispatch(dp->dp_spa->spa_zvol_taskq, zvol_task_cb,
|
||
|
task, TQ_SLEEP);
|
||
|
return (0);
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Traverse all child datasets and apply snapdev appropriately.
|
||
|
* We call dsl_prop_set_sync_impl() here to set the value only on the toplevel
|
||
|
* dataset and read the effective "snapdev" on every child in the callback
|
||
|
* function: this is because the value is not guaranteed to be the same in the
|
||
|
* whole dataset hierarchy.
|
||
|
*/
|
||
|
static void
|
||
|
zvol_set_snapdev_sync(void *arg, dmu_tx_t *tx)
|
||
|
{
|
||
|
zvol_set_prop_int_arg_t *zsda = arg;
|
||
|
dsl_pool_t *dp = dmu_tx_pool(tx);
|
||
|
dsl_dir_t *dd;
|
||
|
dsl_dataset_t *ds;
|
||
|
int error;
|
||
|
|
||
|
VERIFY0(dsl_dir_hold(dp, zsda->zsda_name, FTAG, &dd, NULL));
|
||
|
zsda->zsda_tx = tx;
|
||
|
|
||
|
error = dsl_dataset_hold(dp, zsda->zsda_name, FTAG, &ds);
|
||
|
if (error == 0) {
|
||
|
dsl_prop_set_sync_impl(ds, zfs_prop_to_name(ZFS_PROP_SNAPDEV),
|
||
|
zsda->zsda_source, sizeof (zsda->zsda_value), 1,
|
||
|
&zsda->zsda_value, zsda->zsda_tx);
|
||
|
dsl_dataset_rele(ds, FTAG);
|
||
|
}
|
||
|
dmu_objset_find_dp(dp, dd->dd_object, zvol_set_snapdev_sync_cb,
|
||
|
zsda, DS_FIND_CHILDREN);
|
||
|
|
||
|
dsl_dir_rele(dd, FTAG);
|
||
|
}
|
||
|
|
||
|
int
|
||
|
zvol_set_snapdev(const char *ddname, zprop_source_t source, uint64_t snapdev)
|
||
|
{
|
||
|
zvol_set_prop_int_arg_t zsda;
|
||
|
|
||
|
zsda.zsda_name = ddname;
|
||
|
zsda.zsda_source = source;
|
||
|
zsda.zsda_value = snapdev;
|
||
|
|
||
|
return (dsl_sync_task(ddname, zvol_set_snapdev_check,
|
||
|
zvol_set_snapdev_sync, &zsda, 0, ZFS_SPACE_CHECK_NONE));
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Sanity check the dataset for safe use by the sync task. No additional
|
||
|
* conditions are imposed.
|
||
|
*/
|
||
|
static int
|
||
|
zvol_set_volmode_check(void *arg, dmu_tx_t *tx)
|
||
|
{
|
||
|
zvol_set_prop_int_arg_t *zsda = arg;
|
||
|
dsl_pool_t *dp = dmu_tx_pool(tx);
|
||
|
dsl_dir_t *dd;
|
||
|
int error;
|
||
|
|
||
|
error = dsl_dir_hold(dp, zsda->zsda_name, FTAG, &dd, NULL);
|
||
|
if (error != 0)
|
||
|
return (error);
|
||
|
|
||
|
dsl_dir_rele(dd, FTAG);
|
||
|
|
||
|
return (error);
|
||
|
}
|
||
|
|
||
|
/* ARGSUSED */
|
||
|
static int
|
||
|
zvol_set_volmode_sync_cb(dsl_pool_t *dp, dsl_dataset_t *ds, void *arg)
|
||
|
{
|
||
|
char dsname[MAXNAMELEN];
|
||
|
zvol_task_t *task;
|
||
|
uint64_t volmode;
|
||
|
|
||
|
dsl_dataset_name(ds, dsname);
|
||
|
if (dsl_prop_get_int_ds(ds, "volmode", &volmode) != 0)
|
||
|
return (0);
|
||
|
task = zvol_task_alloc(ZVOL_ASYNC_SET_VOLMODE, dsname, NULL, volmode);
|
||
|
if (task == NULL)
|
||
|
return (0);
|
||
|
|
||
|
(void) taskq_dispatch(dp->dp_spa->spa_zvol_taskq, zvol_task_cb,
|
||
|
task, TQ_SLEEP);
|
||
|
return (0);
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Traverse all child datasets and apply volmode appropriately.
|
||
|
* We call dsl_prop_set_sync_impl() here to set the value only on the toplevel
|
||
|
* dataset and read the effective "volmode" on every child in the callback
|
||
|
* function: this is because the value is not guaranteed to be the same in the
|
||
|
* whole dataset hierarchy.
|
||
|
*/
|
||
|
static void
|
||
|
zvol_set_volmode_sync(void *arg, dmu_tx_t *tx)
|
||
|
{
|
||
|
zvol_set_prop_int_arg_t *zsda = arg;
|
||
|
dsl_pool_t *dp = dmu_tx_pool(tx);
|
||
|
dsl_dir_t *dd;
|
||
|
dsl_dataset_t *ds;
|
||
|
int error;
|
||
|
|
||
|
VERIFY0(dsl_dir_hold(dp, zsda->zsda_name, FTAG, &dd, NULL));
|
||
|
zsda->zsda_tx = tx;
|
||
|
|
||
|
error = dsl_dataset_hold(dp, zsda->zsda_name, FTAG, &ds);
|
||
|
if (error == 0) {
|
||
|
dsl_prop_set_sync_impl(ds, zfs_prop_to_name(ZFS_PROP_VOLMODE),
|
||
|
zsda->zsda_source, sizeof (zsda->zsda_value), 1,
|
||
|
&zsda->zsda_value, zsda->zsda_tx);
|
||
|
dsl_dataset_rele(ds, FTAG);
|
||
|
}
|
||
|
|
||
|
dmu_objset_find_dp(dp, dd->dd_object, zvol_set_volmode_sync_cb,
|
||
|
zsda, DS_FIND_CHILDREN);
|
||
|
|
||
|
dsl_dir_rele(dd, FTAG);
|
||
|
}
|
||
|
|
||
|
int
|
||
|
zvol_set_volmode(const char *ddname, zprop_source_t source, uint64_t volmode)
|
||
|
{
|
||
|
zvol_set_prop_int_arg_t zsda;
|
||
|
|
||
|
zsda.zsda_name = ddname;
|
||
|
zsda.zsda_source = source;
|
||
|
zsda.zsda_value = volmode;
|
||
|
|
||
|
return (dsl_sync_task(ddname, zvol_set_volmode_check,
|
||
|
zvol_set_volmode_sync, &zsda, 0, ZFS_SPACE_CHECK_NONE));
|
||
|
}
|
||
|
|
||
|
void
|
||
|
zvol_create_minors(spa_t *spa, const char *name, boolean_t async)
|
||
|
{
|
||
|
zvol_task_t *task;
|
||
|
taskqid_t id;
|
||
|
|
||
|
task = zvol_task_alloc(ZVOL_ASYNC_CREATE_MINORS, name, NULL, ~0ULL);
|
||
|
if (task == NULL)
|
||
|
return;
|
||
|
|
||
|
id = taskq_dispatch(spa->spa_zvol_taskq, zvol_task_cb, task, TQ_SLEEP);
|
||
|
if ((async == B_FALSE) && (id != TASKQID_INVALID))
|
||
|
taskq_wait_id(spa->spa_zvol_taskq, id);
|
||
|
}
|
||
|
|
||
|
void
|
||
|
zvol_remove_minors(spa_t *spa, const char *name, boolean_t async)
|
||
|
{
|
||
|
zvol_task_t *task;
|
||
|
taskqid_t id;
|
||
|
|
||
|
task = zvol_task_alloc(ZVOL_ASYNC_REMOVE_MINORS, name, NULL, ~0ULL);
|
||
|
if (task == NULL)
|
||
|
return;
|
||
|
|
||
|
id = taskq_dispatch(spa->spa_zvol_taskq, zvol_task_cb, task, TQ_SLEEP);
|
||
|
if ((async == B_FALSE) && (id != TASKQID_INVALID))
|
||
|
taskq_wait_id(spa->spa_zvol_taskq, id);
|
||
|
}
|
||
|
|
||
|
void
|
||
|
zvol_rename_minors(spa_t *spa, const char *name1, const char *name2,
|
||
|
boolean_t async)
|
||
|
{
|
||
|
zvol_task_t *task;
|
||
|
taskqid_t id;
|
||
|
|
||
|
task = zvol_task_alloc(ZVOL_ASYNC_RENAME_MINORS, name1, name2, ~0ULL);
|
||
|
if (task == NULL)
|
||
|
return;
|
||
|
|
||
|
id = taskq_dispatch(spa->spa_zvol_taskq, zvol_task_cb, task, TQ_SLEEP);
|
||
|
if ((async == B_FALSE) && (id != TASKQID_INVALID))
|
||
|
taskq_wait_id(spa->spa_zvol_taskq, id);
|
||
|
}
|
||
|
|
||
|
int
|
||
|
zvol_init(void)
|
||
|
{
|
||
|
int threads = MIN(MAX(zvol_threads, 1), 1024);
|
||
|
int i, error;
|
||
|
|
||
|
list_create(&zvol_state_list, sizeof (zvol_state_t),
|
||
|
offsetof(zvol_state_t, zv_next));
|
||
|
rw_init(&zvol_state_lock, NULL, RW_DEFAULT, NULL);
|
||
|
ida_init(&zvol_ida);
|
||
|
|
||
|
zvol_taskq = taskq_create(ZVOL_DRIVER, threads, maxclsyspri,
|
||
|
threads * 2, INT_MAX, TASKQ_PREPOPULATE | TASKQ_DYNAMIC);
|
||
|
if (zvol_taskq == NULL) {
|
||
|
printk(KERN_INFO "ZFS: taskq_create() failed\n");
|
||
|
error = -ENOMEM;
|
||
|
goto out;
|
||
|
}
|
||
|
|
||
|
zvol_htable = kmem_alloc(ZVOL_HT_SIZE * sizeof (struct hlist_head),
|
||
|
KM_SLEEP);
|
||
|
if (!zvol_htable) {
|
||
|
error = -ENOMEM;
|
||
|
goto out_taskq;
|
||
|
}
|
||
|
for (i = 0; i < ZVOL_HT_SIZE; i++)
|
||
|
INIT_HLIST_HEAD(&zvol_htable[i]);
|
||
|
|
||
|
error = register_blkdev(zvol_major, ZVOL_DRIVER);
|
||
|
if (error) {
|
||
|
printk(KERN_INFO "ZFS: register_blkdev() failed %d\n", error);
|
||
|
goto out_free;
|
||
|
}
|
||
|
|
||
|
blk_register_region(MKDEV(zvol_major, 0), 1UL << MINORBITS,
|
||
|
THIS_MODULE, zvol_probe, NULL, NULL);
|
||
|
|
||
|
return (0);
|
||
|
|
||
|
out_free:
|
||
|
kmem_free(zvol_htable, ZVOL_HT_SIZE * sizeof (struct hlist_head));
|
||
|
out_taskq:
|
||
|
taskq_destroy(zvol_taskq);
|
||
|
out:
|
||
|
ida_destroy(&zvol_ida);
|
||
|
rw_destroy(&zvol_state_lock);
|
||
|
list_destroy(&zvol_state_list);
|
||
|
|
||
|
return (SET_ERROR(error));
|
||
|
}
|
||
|
|
||
|
void
|
||
|
zvol_fini(void)
|
||
|
{
|
||
|
zvol_remove_minors_impl(NULL);
|
||
|
|
||
|
blk_unregister_region(MKDEV(zvol_major, 0), 1UL << MINORBITS);
|
||
|
unregister_blkdev(zvol_major, ZVOL_DRIVER);
|
||
|
kmem_free(zvol_htable, ZVOL_HT_SIZE * sizeof (struct hlist_head));
|
||
|
|
||
|
taskq_destroy(zvol_taskq);
|
||
|
list_destroy(&zvol_state_list);
|
||
|
rw_destroy(&zvol_state_lock);
|
||
|
|
||
|
ida_destroy(&zvol_ida);
|
||
|
}
|
||
|
|
||
|
/* BEGIN CSTYLED */
|
||
|
module_param(zvol_inhibit_dev, uint, 0644);
|
||
|
MODULE_PARM_DESC(zvol_inhibit_dev, "Do not create zvol device nodes");
|
||
|
|
||
|
module_param(zvol_major, uint, 0444);
|
||
|
MODULE_PARM_DESC(zvol_major, "Major number for zvol device");
|
||
|
|
||
|
module_param(zvol_threads, uint, 0444);
|
||
|
MODULE_PARM_DESC(zvol_threads, "Max number of threads to handle I/O requests");
|
||
|
|
||
|
module_param(zvol_request_sync, uint, 0644);
|
||
|
MODULE_PARM_DESC(zvol_request_sync, "Synchronously handle bio requests");
|
||
|
|
||
|
module_param(zvol_max_discard_blocks, ulong, 0444);
|
||
|
MODULE_PARM_DESC(zvol_max_discard_blocks, "Max number of blocks to discard");
|
||
|
|
||
|
module_param(zvol_prefetch_bytes, uint, 0644);
|
||
|
MODULE_PARM_DESC(zvol_prefetch_bytes, "Prefetch N bytes at zvol start+end");
|
||
|
|
||
|
module_param(zvol_volmode, uint, 0644);
|
||
|
MODULE_PARM_DESC(zvol_volmode, "Default volmode property value");
|
||
|
/* END CSTYLED */
|