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19d55079ae
4950 files sometimes can't be removed from a full filesystem Reviewed by: Adam Leventhal <adam.leventhal@delphix.com> Reviewed by: George Wilson <george.wilson@delphix.com> Reviewed by: Sebastien Roy <sebastien.roy@delphix.com> Reviewed by: Boris Protopopov <bprotopopov@hotmail.com> Approved by: Dan McDonald <danmcd@omniti.com> References: https://www.illumos.org/issues/4950 https://github.com/illumos/illumos-gate/commit/4bb7380 Porting notes: - ZoL currently does not log discards to zvols, so the portion of this patch that modifies the discard logging to mark it as freeing space has been discarded. 2. may_delete_now had been removed from zfs_remove() in ZoL. It has been reintroduced. 3. We do not try to emulate vnodes, so the following lines are not valid on Linux: mutex_enter(&vp->v_lock); may_delete_now = vp->v_count == 1 && !vn_has_cached_data(vp); mutex_exit(&vp->v_lock); This has been replaced with: mutex_enter(&zp->z_lock); may_delete_now = atomic_read(&ip->i_count) == 1 && !(zp->z_is_mapped); mutex_exit(&zp->z_lock); Ported-by: Richard Yao <richard.yao@clusterhq.com> Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>
1655 lines
38 KiB
C
1655 lines
38 KiB
C
/*
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* CDDL HEADER START
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*
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* The contents of this file are subject to the terms of the
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* Common Development and Distribution License (the "License").
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* You may not use this file except in compliance with the License.
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*
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* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
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* or http://www.opensolaris.org/os/licensing.
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* See the License for the specific language governing permissions
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* and limitations under the License.
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*
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* When distributing Covered Code, include this CDDL HEADER in each
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* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
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* If applicable, add the following below this CDDL HEADER, with the
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* fields enclosed by brackets "[]" replaced with your own identifying
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* information: Portions Copyright [yyyy] [name of copyright owner]
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*
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* CDDL HEADER END
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*/
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/*
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* Copyright (C) 2008-2010 Lawrence Livermore National Security, LLC.
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* Produced at Lawrence Livermore National Laboratory (cf, DISCLAIMER).
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* Rewritten for Linux by Brian Behlendorf <behlendorf1@llnl.gov>.
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* LLNL-CODE-403049.
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*
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* ZFS volume emulation driver.
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*
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* Makes a DMU object look like a volume of arbitrary size, up to 2^64 bytes.
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* Volumes are accessed through the symbolic links named:
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*
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* /dev/<pool_name>/<dataset_name>
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*
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* Volumes are persistent through reboot and module load. No user command
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* needs to be run before opening and using a device.
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*/
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#include <sys/dbuf.h>
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#include <sys/dmu_traverse.h>
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#include <sys/dsl_dataset.h>
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#include <sys/dsl_prop.h>
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#include <sys/zap.h>
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#include <sys/zfeature.h>
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#include <sys/zil_impl.h>
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#include <sys/zio.h>
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#include <sys/zfs_rlock.h>
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#include <sys/zfs_znode.h>
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#include <sys/zvol.h>
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#include <linux/blkdev_compat.h>
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unsigned int zvol_inhibit_dev = 0;
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unsigned int zvol_major = ZVOL_MAJOR;
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unsigned int zvol_prefetch_bytes = (128 * 1024);
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unsigned long zvol_max_discard_blocks = 16384;
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static kmutex_t zvol_state_lock;
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static list_t zvol_state_list;
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static char *zvol_tag = "zvol_tag";
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/*
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* The in-core state of each volume.
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*/
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typedef struct zvol_state {
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char zv_name[MAXNAMELEN]; /* name */
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uint64_t zv_volsize; /* advertised space */
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uint64_t zv_volblocksize; /* volume block size */
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objset_t *zv_objset; /* objset handle */
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uint32_t zv_flags; /* ZVOL_* flags */
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uint32_t zv_open_count; /* open counts */
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uint32_t zv_changed; /* disk changed */
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zilog_t *zv_zilog; /* ZIL handle */
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znode_t zv_znode; /* for range locking */
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dmu_buf_t *zv_dbuf; /* bonus handle */
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dev_t zv_dev; /* device id */
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struct gendisk *zv_disk; /* generic disk */
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struct request_queue *zv_queue; /* request queue */
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list_node_t zv_next; /* next zvol_state_t linkage */
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} zvol_state_t;
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#define ZVOL_RDONLY 0x1
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/*
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* Find the next available range of ZVOL_MINORS minor numbers. The
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* zvol_state_list is kept in ascending minor order so we simply need
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* to scan the list for the first gap in the sequence. This allows us
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* to recycle minor number as devices are created and removed.
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*/
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static int
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zvol_find_minor(unsigned *minor)
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{
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zvol_state_t *zv;
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*minor = 0;
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ASSERT(MUTEX_HELD(&zvol_state_lock));
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for (zv = list_head(&zvol_state_list); zv != NULL;
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zv = list_next(&zvol_state_list, zv), *minor += ZVOL_MINORS) {
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if (MINOR(zv->zv_dev) != MINOR(*minor))
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break;
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}
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/* All minors are in use */
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if (*minor >= (1 << MINORBITS))
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return (SET_ERROR(ENXIO));
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return (0);
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}
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/*
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* Find a zvol_state_t given the full major+minor dev_t.
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*/
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static zvol_state_t *
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zvol_find_by_dev(dev_t dev)
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{
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zvol_state_t *zv;
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ASSERT(MUTEX_HELD(&zvol_state_lock));
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for (zv = list_head(&zvol_state_list); zv != NULL;
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zv = list_next(&zvol_state_list, zv)) {
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if (zv->zv_dev == dev)
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return (zv);
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}
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return (NULL);
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}
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/*
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* Find a zvol_state_t given the name provided at zvol_alloc() time.
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*/
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static zvol_state_t *
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zvol_find_by_name(const char *name)
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{
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zvol_state_t *zv;
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ASSERT(MUTEX_HELD(&zvol_state_lock));
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for (zv = list_head(&zvol_state_list); zv != NULL;
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zv = list_next(&zvol_state_list, zv)) {
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if (strncmp(zv->zv_name, name, MAXNAMELEN) == 0)
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return (zv);
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}
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return (NULL);
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}
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/*
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* Given a path, return TRUE if path is a ZVOL.
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*/
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boolean_t
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zvol_is_zvol(const char *device)
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{
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struct block_device *bdev;
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unsigned int major;
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bdev = lookup_bdev(device);
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if (IS_ERR(bdev))
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return (B_FALSE);
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major = MAJOR(bdev->bd_dev);
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bdput(bdev);
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if (major == zvol_major)
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return (B_TRUE);
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return (B_FALSE);
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}
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/*
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* ZFS_IOC_CREATE callback handles dmu zvol and zap object creation.
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*/
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void
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zvol_create_cb(objset_t *os, void *arg, cred_t *cr, dmu_tx_t *tx)
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{
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zfs_creat_t *zct = arg;
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nvlist_t *nvprops = zct->zct_props;
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int error;
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uint64_t volblocksize, volsize;
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VERIFY(nvlist_lookup_uint64(nvprops,
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zfs_prop_to_name(ZFS_PROP_VOLSIZE), &volsize) == 0);
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if (nvlist_lookup_uint64(nvprops,
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zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), &volblocksize) != 0)
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volblocksize = zfs_prop_default_numeric(ZFS_PROP_VOLBLOCKSIZE);
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/*
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* These properties must be removed from the list so the generic
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* property setting step won't apply to them.
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*/
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VERIFY(nvlist_remove_all(nvprops,
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zfs_prop_to_name(ZFS_PROP_VOLSIZE)) == 0);
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(void) nvlist_remove_all(nvprops,
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zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE));
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error = dmu_object_claim(os, ZVOL_OBJ, DMU_OT_ZVOL, volblocksize,
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DMU_OT_NONE, 0, tx);
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ASSERT(error == 0);
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error = zap_create_claim(os, ZVOL_ZAP_OBJ, DMU_OT_ZVOL_PROP,
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DMU_OT_NONE, 0, tx);
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ASSERT(error == 0);
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error = zap_update(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize, tx);
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ASSERT(error == 0);
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}
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/*
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* ZFS_IOC_OBJSET_STATS entry point.
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*/
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int
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zvol_get_stats(objset_t *os, nvlist_t *nv)
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{
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int error;
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dmu_object_info_t *doi;
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uint64_t val;
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error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &val);
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if (error)
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return (SET_ERROR(error));
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dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_VOLSIZE, val);
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doi = kmem_alloc(sizeof (dmu_object_info_t), KM_SLEEP);
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error = dmu_object_info(os, ZVOL_OBJ, doi);
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if (error == 0) {
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dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_VOLBLOCKSIZE,
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doi->doi_data_block_size);
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}
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kmem_free(doi, sizeof (dmu_object_info_t));
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return (SET_ERROR(error));
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}
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static void
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zvol_size_changed(zvol_state_t *zv, uint64_t volsize)
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{
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struct block_device *bdev;
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bdev = bdget_disk(zv->zv_disk, 0);
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if (bdev == NULL)
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return;
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set_capacity(zv->zv_disk, volsize >> 9);
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zv->zv_volsize = volsize;
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check_disk_size_change(zv->zv_disk, bdev);
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bdput(bdev);
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}
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/*
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* Sanity check volume size.
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*/
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int
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zvol_check_volsize(uint64_t volsize, uint64_t blocksize)
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{
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if (volsize == 0)
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return (SET_ERROR(EINVAL));
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if (volsize % blocksize != 0)
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return (SET_ERROR(EINVAL));
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#ifdef _ILP32
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if (volsize - 1 > MAXOFFSET_T)
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return (SET_ERROR(EOVERFLOW));
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#endif
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return (0);
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}
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/*
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* Ensure the zap is flushed then inform the VFS of the capacity change.
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*/
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static int
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zvol_update_volsize(uint64_t volsize, objset_t *os)
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{
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dmu_tx_t *tx;
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int error;
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ASSERT(MUTEX_HELD(&zvol_state_lock));
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tx = dmu_tx_create(os);
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dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL);
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dmu_tx_mark_netfree(tx);
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error = dmu_tx_assign(tx, TXG_WAIT);
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if (error) {
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dmu_tx_abort(tx);
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return (SET_ERROR(error));
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}
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error = zap_update(os, ZVOL_ZAP_OBJ, "size", 8, 1,
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&volsize, tx);
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dmu_tx_commit(tx);
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if (error == 0)
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error = dmu_free_long_range(os,
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ZVOL_OBJ, volsize, DMU_OBJECT_END);
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return (error);
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}
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static int
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zvol_update_live_volsize(zvol_state_t *zv, uint64_t volsize)
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{
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zvol_size_changed(zv, volsize);
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/*
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* We should post a event here describing the expansion. However,
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* the zfs_ereport_post() interface doesn't nicely support posting
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* events for zvols, it assumes events relate to vdevs or zios.
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*/
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return (0);
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}
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/*
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* Set ZFS_PROP_VOLSIZE set entry point.
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*/
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int
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zvol_set_volsize(const char *name, uint64_t volsize)
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{
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zvol_state_t *zv = NULL;
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objset_t *os = NULL;
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int error;
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dmu_object_info_t *doi;
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uint64_t readonly;
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boolean_t owned = B_FALSE;
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error = dsl_prop_get_integer(name,
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zfs_prop_to_name(ZFS_PROP_READONLY), &readonly, NULL);
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if (error != 0)
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return (SET_ERROR(error));
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if (readonly)
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return (SET_ERROR(EROFS));
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mutex_enter(&zvol_state_lock);
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zv = zvol_find_by_name(name);
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if (zv == NULL || zv->zv_objset == NULL) {
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if ((error = dmu_objset_own(name, DMU_OST_ZVOL, B_FALSE,
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FTAG, &os)) != 0) {
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mutex_exit(&zvol_state_lock);
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return (SET_ERROR(error));
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}
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owned = B_TRUE;
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if (zv != NULL)
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zv->zv_objset = os;
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} else {
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os = zv->zv_objset;
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}
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doi = kmem_alloc(sizeof (dmu_object_info_t), KM_SLEEP);
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if ((error = dmu_object_info(os, ZVOL_OBJ, doi)) ||
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(error = zvol_check_volsize(volsize, doi->doi_data_block_size)))
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goto out;
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error = zvol_update_volsize(volsize, os);
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kmem_free(doi, sizeof (dmu_object_info_t));
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if (error == 0 && zv != NULL)
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error = zvol_update_live_volsize(zv, volsize);
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out:
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if (owned) {
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dmu_objset_disown(os, FTAG);
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if (zv != NULL)
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zv->zv_objset = NULL;
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}
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mutex_exit(&zvol_state_lock);
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return (error);
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}
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|
|
/*
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* Sanity check volume block size.
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*/
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int
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zvol_check_volblocksize(const char *name, uint64_t volblocksize)
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{
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/* Record sizes above 128k need the feature to be enabled */
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if (volblocksize > SPA_OLD_MAXBLOCKSIZE) {
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spa_t *spa;
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int error;
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if ((error = spa_open(name, &spa, FTAG)) != 0)
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return (error);
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|
|
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if (!spa_feature_is_enabled(spa, SPA_FEATURE_LARGE_BLOCKS)) {
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spa_close(spa, FTAG);
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return (SET_ERROR(ENOTSUP));
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}
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|
|
|
/*
|
|
* We don't allow setting the property above 1MB,
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* unless the tunable has been changed.
|
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*/
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if (volblocksize > zfs_max_recordsize)
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return (SET_ERROR(EDOM));
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|
|
|
spa_close(spa, FTAG);
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}
|
|
|
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if (volblocksize < SPA_MINBLOCKSIZE ||
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volblocksize > SPA_MAXBLOCKSIZE ||
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!ISP2(volblocksize))
|
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return (SET_ERROR(EDOM));
|
|
|
|
return (0);
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|
}
|
|
|
|
/*
|
|
* 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;
|
|
|
|
mutex_enter(&zvol_state_lock);
|
|
|
|
zv = zvol_find_by_name(name);
|
|
if (zv == NULL) {
|
|
error = SET_ERROR(ENXIO);
|
|
goto out;
|
|
}
|
|
|
|
if (zv->zv_flags & ZVOL_RDONLY) {
|
|
error = SET_ERROR(EROFS);
|
|
goto out;
|
|
}
|
|
|
|
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;
|
|
}
|
|
out:
|
|
mutex_exit(&zvol_state_lock);
|
|
|
|
return (SET_ERROR(error));
|
|
}
|
|
|
|
/*
|
|
* Replay a TX_WRITE ZIL transaction that didn't get committed
|
|
* after a system failure
|
|
*/
|
|
static int
|
|
zvol_replay_write(zvol_state_t *zv, lr_write_t *lr, boolean_t byteswap)
|
|
{
|
|
objset_t *os = zv->zv_objset;
|
|
char *data = (char *)(lr + 1); /* data follows lr_write_t */
|
|
uint64_t off = lr->lr_offset;
|
|
uint64_t len = lr->lr_length;
|
|
dmu_tx_t *tx;
|
|
int error;
|
|
|
|
if (byteswap)
|
|
byteswap_uint64_array(lr, sizeof (*lr));
|
|
|
|
tx = dmu_tx_create(os);
|
|
dmu_tx_hold_write(tx, ZVOL_OBJ, off, len);
|
|
error = dmu_tx_assign(tx, TXG_WAIT);
|
|
if (error) {
|
|
dmu_tx_abort(tx);
|
|
} else {
|
|
dmu_write(os, ZVOL_OBJ, off, len, data, tx);
|
|
dmu_tx_commit(tx);
|
|
}
|
|
|
|
return (SET_ERROR(error));
|
|
}
|
|
|
|
static int
|
|
zvol_replay_err(zvol_state_t *zv, lr_t *lr, boolean_t byteswap)
|
|
{
|
|
return (SET_ERROR(ENOTSUP));
|
|
}
|
|
|
|
/*
|
|
* Callback vectors for replaying records.
|
|
* Only TX_WRITE is needed for zvol.
|
|
*/
|
|
zil_replay_func_t zvol_replay_vector[TX_MAX_TYPE] = {
|
|
(zil_replay_func_t)zvol_replay_err, /* no such transaction type */
|
|
(zil_replay_func_t)zvol_replay_err, /* TX_CREATE */
|
|
(zil_replay_func_t)zvol_replay_err, /* TX_MKDIR */
|
|
(zil_replay_func_t)zvol_replay_err, /* TX_MKXATTR */
|
|
(zil_replay_func_t)zvol_replay_err, /* TX_SYMLINK */
|
|
(zil_replay_func_t)zvol_replay_err, /* TX_REMOVE */
|
|
(zil_replay_func_t)zvol_replay_err, /* TX_RMDIR */
|
|
(zil_replay_func_t)zvol_replay_err, /* TX_LINK */
|
|
(zil_replay_func_t)zvol_replay_err, /* TX_RENAME */
|
|
(zil_replay_func_t)zvol_replay_write, /* TX_WRITE */
|
|
(zil_replay_func_t)zvol_replay_err, /* TX_TRUNCATE */
|
|
(zil_replay_func_t)zvol_replay_err, /* TX_SETATTR */
|
|
(zil_replay_func_t)zvol_replay_err, /* TX_ACL */
|
|
};
|
|
|
|
/*
|
|
* 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;
|
|
boolean_t slogging;
|
|
ssize_t immediate_write_sz;
|
|
|
|
if (zil_replaying(zilog, tx))
|
|
return;
|
|
|
|
immediate_write_sz = (zilog->zl_logbias == ZFS_LOGBIAS_THROUGHPUT)
|
|
? 0 : zvol_immediate_write_sz;
|
|
slogging = spa_has_slogs(zilog->zl_spa) &&
|
|
(zilog->zl_logbias == ZFS_LOGBIAS_LATENCY);
|
|
|
|
while (size) {
|
|
itx_t *itx;
|
|
lr_write_t *lr;
|
|
ssize_t len;
|
|
itx_wr_state_t write_state;
|
|
|
|
/*
|
|
* Unlike zfs_log_write() we can be called with
|
|
* up to DMU_MAX_ACCESS/2 (5MB) writes.
|
|
*/
|
|
if (blocksize > immediate_write_sz && !slogging &&
|
|
size >= blocksize && offset % blocksize == 0) {
|
|
write_state = WR_INDIRECT; /* uses dmu_sync */
|
|
len = blocksize;
|
|
} else if (sync) {
|
|
write_state = WR_COPIED;
|
|
len = MIN(ZIL_MAX_LOG_DATA, size);
|
|
} else {
|
|
write_state = WR_NEED_COPY;
|
|
len = MIN(ZIL_MAX_LOG_DATA, size);
|
|
}
|
|
|
|
itx = zil_itx_create(TX_WRITE, sizeof (*lr) +
|
|
(write_state == WR_COPIED ? len : 0));
|
|
lr = (lr_write_t *)&itx->itx_lr;
|
|
if (write_state == WR_COPIED && dmu_read(zv->zv_objset,
|
|
ZVOL_OBJ, 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;
|
|
write_state = WR_NEED_COPY;
|
|
}
|
|
|
|
itx->itx_wr_state = write_state;
|
|
if (write_state == WR_NEED_COPY)
|
|
itx->itx_sod += len;
|
|
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;
|
|
}
|
|
}
|
|
|
|
static int
|
|
zvol_write(struct bio *bio)
|
|
{
|
|
zvol_state_t *zv = bio->bi_bdev->bd_disk->private_data;
|
|
uint64_t offset = BIO_BI_SECTOR(bio) << 9;
|
|
uint64_t size = BIO_BI_SIZE(bio);
|
|
int error = 0;
|
|
dmu_tx_t *tx;
|
|
rl_t *rl;
|
|
uio_t uio;
|
|
|
|
if (bio->bi_rw & VDEV_REQ_FLUSH)
|
|
zil_commit(zv->zv_zilog, ZVOL_OBJ);
|
|
|
|
/*
|
|
* Some requests are just for flush and nothing else.
|
|
*/
|
|
if (size == 0)
|
|
goto out;
|
|
|
|
uio.uio_bvec = &bio->bi_io_vec[BIO_BI_IDX(bio)];
|
|
uio.uio_skip = BIO_BI_SKIP(bio);
|
|
uio.uio_resid = size;
|
|
uio.uio_iovcnt = bio->bi_vcnt - BIO_BI_IDX(bio);
|
|
uio.uio_loffset = offset;
|
|
uio.uio_limit = MAXOFFSET_T;
|
|
uio.uio_segflg = UIO_BVEC;
|
|
|
|
rl = zfs_range_lock(&zv->zv_znode, offset, size, RL_WRITER);
|
|
|
|
tx = dmu_tx_create(zv->zv_objset);
|
|
dmu_tx_hold_write(tx, ZVOL_OBJ, offset, size);
|
|
|
|
/* This will only fail for ENOSPC */
|
|
error = dmu_tx_assign(tx, TXG_WAIT);
|
|
if (error) {
|
|
dmu_tx_abort(tx);
|
|
zfs_range_unlock(rl);
|
|
goto out;
|
|
}
|
|
|
|
error = dmu_write_uio(zv->zv_objset, ZVOL_OBJ, &uio, size, tx);
|
|
if (error == 0)
|
|
zvol_log_write(zv, tx, offset, size,
|
|
!!(bio->bi_rw & VDEV_REQ_FUA));
|
|
|
|
dmu_tx_commit(tx);
|
|
zfs_range_unlock(rl);
|
|
|
|
if ((bio->bi_rw & VDEV_REQ_FUA) ||
|
|
zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS)
|
|
zil_commit(zv->zv_zilog, ZVOL_OBJ);
|
|
|
|
out:
|
|
return (error);
|
|
}
|
|
|
|
static int
|
|
zvol_discard(struct bio *bio)
|
|
{
|
|
zvol_state_t *zv = bio->bi_bdev->bd_disk->private_data;
|
|
uint64_t start = BIO_BI_SECTOR(bio) << 9;
|
|
uint64_t size = BIO_BI_SIZE(bio);
|
|
uint64_t end = start + size;
|
|
int error;
|
|
rl_t *rl;
|
|
|
|
if (end > zv->zv_volsize)
|
|
return (SET_ERROR(EIO));
|
|
|
|
/*
|
|
* Align the request to volume block boundaries when REQ_SECURE is
|
|
* available, but not requested. If we don't, then this will force
|
|
* dnode_free_range() to zero out the unaligned parts, which is slow
|
|
* (read-modify-write) and useless since we are not freeing any space
|
|
* by doing so. Kernels that do not support REQ_SECURE (2.6.32 through
|
|
* 2.6.35) will not receive this optimization.
|
|
*/
|
|
#ifdef REQ_SECURE
|
|
if (!(bio->bi_rw & REQ_SECURE)) {
|
|
start = P2ROUNDUP(start, zv->zv_volblocksize);
|
|
end = P2ALIGN(end, zv->zv_volblocksize);
|
|
size = end - start;
|
|
}
|
|
#endif
|
|
|
|
if (start >= end)
|
|
return (0);
|
|
|
|
rl = zfs_range_lock(&zv->zv_znode, start, size, RL_WRITER);
|
|
|
|
error = dmu_free_long_range(zv->zv_objset, ZVOL_OBJ, start, size);
|
|
|
|
/*
|
|
* TODO: maybe we should add the operation to the log.
|
|
*/
|
|
|
|
zfs_range_unlock(rl);
|
|
|
|
return (error);
|
|
}
|
|
|
|
static int
|
|
zvol_read(struct bio *bio)
|
|
{
|
|
zvol_state_t *zv = bio->bi_bdev->bd_disk->private_data;
|
|
uint64_t offset = BIO_BI_SECTOR(bio) << 9;
|
|
uint64_t size = BIO_BI_SIZE(bio);
|
|
int error;
|
|
rl_t *rl;
|
|
uio_t uio;
|
|
|
|
if (size == 0)
|
|
return (0);
|
|
|
|
uio.uio_bvec = &bio->bi_io_vec[BIO_BI_IDX(bio)];
|
|
uio.uio_skip = BIO_BI_SKIP(bio);
|
|
uio.uio_resid = size;
|
|
uio.uio_iovcnt = bio->bi_vcnt - BIO_BI_IDX(bio);
|
|
uio.uio_loffset = offset;
|
|
uio.uio_limit = MAXOFFSET_T;
|
|
uio.uio_segflg = UIO_BVEC;
|
|
|
|
rl = zfs_range_lock(&zv->zv_znode, offset, size, RL_READER);
|
|
|
|
error = dmu_read_uio(zv->zv_objset, ZVOL_OBJ, &uio, size);
|
|
|
|
zfs_range_unlock(rl);
|
|
|
|
/* convert checksum errors into IO errors */
|
|
if (error == ECKSUM)
|
|
error = SET_ERROR(EIO);
|
|
|
|
return (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);
|
|
unsigned int sectors = bio_sectors(bio);
|
|
int rw = bio_data_dir(bio);
|
|
#ifdef HAVE_GENERIC_IO_ACCT
|
|
unsigned long start = jiffies;
|
|
#endif
|
|
int error = 0;
|
|
|
|
if (bio_has_data(bio) && offset + sectors >
|
|
get_capacity(zv->zv_disk)) {
|
|
printk(KERN_INFO
|
|
"%s: bad access: block=%llu, count=%lu\n",
|
|
zv->zv_disk->disk_name,
|
|
(long long unsigned)offset,
|
|
(long unsigned)sectors);
|
|
error = SET_ERROR(EIO);
|
|
goto out1;
|
|
}
|
|
|
|
generic_start_io_acct(rw, sectors, &zv->zv_disk->part0);
|
|
|
|
if (rw == WRITE) {
|
|
if (unlikely(zv->zv_flags & ZVOL_RDONLY)) {
|
|
error = SET_ERROR(EROFS);
|
|
goto out2;
|
|
}
|
|
|
|
if (bio->bi_rw & VDEV_REQ_DISCARD) {
|
|
error = zvol_discard(bio);
|
|
goto out2;
|
|
}
|
|
|
|
error = zvol_write(bio);
|
|
} else
|
|
error = zvol_read(bio);
|
|
|
|
out2:
|
|
generic_end_io_acct(rw, &zv->zv_disk->part0, start);
|
|
out1:
|
|
BIO_END_IO(bio, -error);
|
|
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
|
|
}
|
|
|
|
static void
|
|
zvol_get_done(zgd_t *zgd, int error)
|
|
{
|
|
if (zgd->zgd_db)
|
|
dmu_buf_rele(zgd->zgd_db, zgd);
|
|
|
|
zfs_range_unlock(zgd->zgd_rl);
|
|
|
|
if (error == 0 && zgd->zgd_bp)
|
|
zil_add_block(zgd->zgd_zilog, zgd->zgd_bp);
|
|
|
|
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, zio_t *zio)
|
|
{
|
|
zvol_state_t *zv = arg;
|
|
objset_t *os = zv->zv_objset;
|
|
uint64_t object = ZVOL_OBJ;
|
|
uint64_t offset = lr->lr_offset;
|
|
uint64_t size = lr->lr_length;
|
|
blkptr_t *bp = &lr->lr_blkptr;
|
|
dmu_buf_t *db;
|
|
zgd_t *zgd;
|
|
int error;
|
|
|
|
ASSERT(zio != NULL);
|
|
ASSERT(size != 0);
|
|
|
|
zgd = (zgd_t *)kmem_zalloc(sizeof (zgd_t), KM_SLEEP);
|
|
zgd->zgd_zilog = zv->zv_zilog;
|
|
zgd->zgd_rl = zfs_range_lock(&zv->zv_znode, offset, size, RL_READER);
|
|
|
|
/*
|
|
* 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 */
|
|
error = dmu_read(os, object, offset, size, buf,
|
|
DMU_READ_NO_PREFETCH);
|
|
} else {
|
|
size = zv->zv_volblocksize;
|
|
offset = P2ALIGN_TYPED(offset, size, uint64_t);
|
|
error = dmu_buf_hold(os, object, offset, zgd, &db,
|
|
DMU_READ_NO_PREFETCH);
|
|
if (error == 0) {
|
|
blkptr_t *obp = dmu_buf_get_blkptr(db);
|
|
if (obp) {
|
|
ASSERT(BP_IS_HOLE(bp));
|
|
*bp = *obp;
|
|
}
|
|
|
|
zgd->zgd_db = db;
|
|
zgd->zgd_bp = &lr->lr_blkptr;
|
|
|
|
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));
|
|
}
|
|
|
|
/*
|
|
* The zvol_state_t's are inserted in increasing MINOR(dev_t) order.
|
|
*/
|
|
static void
|
|
zvol_insert(zvol_state_t *zv_insert)
|
|
{
|
|
zvol_state_t *zv = NULL;
|
|
|
|
ASSERT(MUTEX_HELD(&zvol_state_lock));
|
|
ASSERT3U(MINOR(zv_insert->zv_dev) & ZVOL_MINOR_MASK, ==, 0);
|
|
for (zv = list_head(&zvol_state_list); zv != NULL;
|
|
zv = list_next(&zvol_state_list, zv)) {
|
|
if (MINOR(zv->zv_dev) > MINOR(zv_insert->zv_dev))
|
|
break;
|
|
}
|
|
|
|
list_insert_before(&zvol_state_list, zv, zv_insert);
|
|
}
|
|
|
|
/*
|
|
* Simply remove the zvol from to list of zvols.
|
|
*/
|
|
static void
|
|
zvol_remove(zvol_state_t *zv_remove)
|
|
{
|
|
ASSERT(MUTEX_HELD(&zvol_state_lock));
|
|
list_remove(&zvol_state_list, zv_remove);
|
|
}
|
|
|
|
static int
|
|
zvol_first_open(zvol_state_t *zv)
|
|
{
|
|
objset_t *os;
|
|
uint64_t volsize;
|
|
int locked = 0;
|
|
int error;
|
|
uint64_t ro;
|
|
|
|
/*
|
|
* 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.
|
|
*
|
|
* 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));
|
|
}
|
|
|
|
error = dsl_prop_get_integer(zv->zv_name, "readonly", &ro, NULL);
|
|
if (error)
|
|
goto out_mutex;
|
|
|
|
/* lie and say we're read-only */
|
|
error = dmu_objset_own(zv->zv_name, DMU_OST_ZVOL, 1, zvol_tag, &os);
|
|
if (error)
|
|
goto out_mutex;
|
|
|
|
error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize);
|
|
if (error) {
|
|
dmu_objset_disown(os, zvol_tag);
|
|
goto out_mutex;
|
|
}
|
|
|
|
zv->zv_objset = os;
|
|
error = dmu_bonus_hold(os, ZVOL_OBJ, zvol_tag, &zv->zv_dbuf);
|
|
if (error) {
|
|
dmu_objset_disown(os, zvol_tag);
|
|
goto out_mutex;
|
|
}
|
|
|
|
set_capacity(zv->zv_disk, volsize >> 9);
|
|
zv->zv_volsize = volsize;
|
|
zv->zv_zilog = zil_open(os, zvol_get_data);
|
|
|
|
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;
|
|
}
|
|
|
|
out_mutex:
|
|
if (locked)
|
|
mutex_exit(&spa_namespace_lock);
|
|
|
|
return (SET_ERROR(-error));
|
|
}
|
|
|
|
static void
|
|
zvol_last_close(zvol_state_t *zv)
|
|
{
|
|
zil_close(zv->zv_zilog);
|
|
zv->zv_zilog = NULL;
|
|
|
|
dmu_buf_rele(zv->zv_dbuf, zvol_tag);
|
|
zv->zv_dbuf = NULL;
|
|
|
|
/*
|
|
* Evict cached data
|
|
*/
|
|
if (dsl_dataset_is_dirty(dmu_objset_ds(zv->zv_objset)) &&
|
|
!(zv->zv_flags & ZVOL_RDONLY))
|
|
txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0);
|
|
(void) dmu_objset_evict_dbufs(zv->zv_objset);
|
|
|
|
dmu_objset_disown(zv->zv_objset, zvol_tag);
|
|
zv->zv_objset = NULL;
|
|
}
|
|
|
|
static int
|
|
zvol_open(struct block_device *bdev, fmode_t flag)
|
|
{
|
|
zvol_state_t *zv = bdev->bd_disk->private_data;
|
|
int error = 0, drop_mutex = 0;
|
|
|
|
/*
|
|
* If the caller is already holding the mutex do not take it
|
|
* again, this will happen as part of zvol_create_minor().
|
|
* Once add_disk() is called the device is live and the kernel
|
|
* will attempt to open it to read the partition information.
|
|
*/
|
|
if (!mutex_owned(&zvol_state_lock)) {
|
|
mutex_enter(&zvol_state_lock);
|
|
drop_mutex = 1;
|
|
}
|
|
|
|
ASSERT3P(zv, !=, NULL);
|
|
|
|
if (zv->zv_open_count == 0) {
|
|
error = zvol_first_open(zv);
|
|
if (error)
|
|
goto out_mutex;
|
|
}
|
|
|
|
if ((flag & FMODE_WRITE) && (zv->zv_flags & ZVOL_RDONLY)) {
|
|
error = -EROFS;
|
|
goto out_open_count;
|
|
}
|
|
|
|
zv->zv_open_count++;
|
|
|
|
out_open_count:
|
|
if (zv->zv_open_count == 0)
|
|
zvol_last_close(zv);
|
|
|
|
out_mutex:
|
|
if (drop_mutex)
|
|
mutex_exit(&zvol_state_lock);
|
|
|
|
check_disk_change(bdev);
|
|
|
|
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 = disk->private_data;
|
|
int drop_mutex = 0;
|
|
|
|
if (!mutex_owned(&zvol_state_lock)) {
|
|
mutex_enter(&zvol_state_lock);
|
|
drop_mutex = 1;
|
|
}
|
|
|
|
if (zv->zv_open_count > 0) {
|
|
zv->zv_open_count--;
|
|
if (zv->zv_open_count == 0)
|
|
zvol_last_close(zv);
|
|
}
|
|
|
|
if (drop_mutex)
|
|
mutex_exit(&zvol_state_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;
|
|
|
|
if (zv == NULL)
|
|
return (SET_ERROR(-ENXIO));
|
|
|
|
switch (cmd) {
|
|
case BLKFLSBUF:
|
|
zil_commit(zv->zv_zilog, ZVOL_OBJ);
|
|
break;
|
|
case BLKZNAME:
|
|
error = copy_to_user((void *)arg, zv->zv_name, MAXNAMELEN);
|
|
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
|
|
|
|
static int zvol_media_changed(struct gendisk *disk)
|
|
{
|
|
zvol_state_t *zv = disk->private_data;
|
|
|
|
return (zv->zv_changed);
|
|
}
|
|
|
|
static int zvol_revalidate_disk(struct gendisk *disk)
|
|
{
|
|
zvol_state_t *zv = disk->private_data;
|
|
|
|
zv->zv_changed = 0;
|
|
set_capacity(zv->zv_disk, zv->zv_volsize >> 9);
|
|
|
|
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 = 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;
|
|
|
|
mutex_enter(&zvol_state_lock);
|
|
zv = zvol_find_by_dev(dev);
|
|
kobj = zv ? get_disk(zv->zv_disk) : NULL;
|
|
mutex_exit(&zvol_state_lock);
|
|
|
|
return (kobj);
|
|
}
|
|
|
|
#ifdef HAVE_BDEV_BLOCK_DEVICE_OPERATIONS
|
|
static struct block_device_operations zvol_ops = {
|
|
.open = zvol_open,
|
|
.release = zvol_release,
|
|
.ioctl = zvol_ioctl,
|
|
.compat_ioctl = zvol_compat_ioctl,
|
|
.media_changed = zvol_media_changed,
|
|
.revalidate_disk = zvol_revalidate_disk,
|
|
.getgeo = zvol_getgeo,
|
|
.owner = THIS_MODULE,
|
|
};
|
|
|
|
#else /* HAVE_BDEV_BLOCK_DEVICE_OPERATIONS */
|
|
|
|
static int
|
|
zvol_open_by_inode(struct inode *inode, struct file *file)
|
|
{
|
|
return (zvol_open(inode->i_bdev, file->f_mode));
|
|
}
|
|
|
|
static int
|
|
zvol_release_by_inode(struct inode *inode, struct file *file)
|
|
{
|
|
return (zvol_release(inode->i_bdev->bd_disk, file->f_mode));
|
|
}
|
|
|
|
static int
|
|
zvol_ioctl_by_inode(struct inode *inode, struct file *file,
|
|
unsigned int cmd, unsigned long arg)
|
|
{
|
|
if (file == NULL || inode == NULL)
|
|
return (SET_ERROR(-EINVAL));
|
|
|
|
return (zvol_ioctl(inode->i_bdev, file->f_mode, cmd, arg));
|
|
}
|
|
|
|
#ifdef CONFIG_COMPAT
|
|
static long
|
|
zvol_compat_ioctl_by_inode(struct file *file,
|
|
unsigned int cmd, unsigned long arg)
|
|
{
|
|
if (file == NULL)
|
|
return (SET_ERROR(-EINVAL));
|
|
|
|
return (zvol_compat_ioctl(file->f_dentry->d_inode->i_bdev,
|
|
file->f_mode, cmd, arg));
|
|
}
|
|
#else
|
|
#define zvol_compat_ioctl_by_inode NULL
|
|
#endif
|
|
|
|
static struct block_device_operations zvol_ops = {
|
|
.open = zvol_open_by_inode,
|
|
.release = zvol_release_by_inode,
|
|
.ioctl = zvol_ioctl_by_inode,
|
|
.compat_ioctl = zvol_compat_ioctl_by_inode,
|
|
.media_changed = zvol_media_changed,
|
|
.revalidate_disk = zvol_revalidate_disk,
|
|
.getgeo = zvol_getgeo,
|
|
.owner = THIS_MODULE,
|
|
};
|
|
#endif /* HAVE_BDEV_BLOCK_DEVICE_OPERATIONS */
|
|
|
|
/*
|
|
* 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;
|
|
|
|
zv = kmem_zalloc(sizeof (zvol_state_t), KM_SLEEP);
|
|
|
|
list_link_init(&zv->zv_next);
|
|
|
|
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);
|
|
|
|
#ifdef HAVE_BLK_QUEUE_FLUSH
|
|
blk_queue_flush(zv->zv_queue, VDEV_REQ_FLUSH | VDEV_REQ_FUA);
|
|
#else
|
|
blk_queue_ordered(zv->zv_queue, QUEUE_ORDERED_DRAIN, NULL);
|
|
#endif /* HAVE_BLK_QUEUE_FLUSH */
|
|
|
|
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);
|
|
|
|
mutex_init(&zv->zv_znode.z_range_lock, NULL, MUTEX_DEFAULT, NULL);
|
|
avl_create(&zv->zv_znode.z_range_avl, zfs_range_compare,
|
|
sizeof (rl_t), offsetof(rl_t, r_node));
|
|
zv->zv_znode.z_is_zvol = TRUE;
|
|
|
|
zv->zv_disk->major = zvol_major;
|
|
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().
|
|
*/
|
|
static void
|
|
zvol_free(zvol_state_t *zv)
|
|
{
|
|
avl_destroy(&zv->zv_znode.z_range_avl);
|
|
mutex_destroy(&zv->zv_znode.z_range_lock);
|
|
|
|
del_gendisk(zv->zv_disk);
|
|
blk_cleanup_queue(zv->zv_queue);
|
|
put_disk(zv->zv_disk);
|
|
|
|
kmem_free(zv, sizeof (zvol_state_t));
|
|
}
|
|
|
|
static int
|
|
__zvol_snapdev_hidden(const char *name)
|
|
{
|
|
uint64_t snapdev;
|
|
char *parent;
|
|
char *atp;
|
|
int error = 0;
|
|
|
|
parent = kmem_alloc(MAXPATHLEN, KM_SLEEP);
|
|
(void) strlcpy(parent, name, MAXPATHLEN);
|
|
|
|
if ((atp = strrchr(parent, '@')) != NULL) {
|
|
*atp = '\0';
|
|
error = dsl_prop_get_integer(parent, "snapdev", &snapdev, NULL);
|
|
if ((error == 0) && (snapdev == ZFS_SNAPDEV_HIDDEN))
|
|
error = SET_ERROR(ENODEV);
|
|
}
|
|
|
|
kmem_free(parent, MAXPATHLEN);
|
|
|
|
return (SET_ERROR(error));
|
|
}
|
|
|
|
static int
|
|
__zvol_create_minor(const char *name, boolean_t ignore_snapdev)
|
|
{
|
|
zvol_state_t *zv;
|
|
objset_t *os;
|
|
dmu_object_info_t *doi;
|
|
uint64_t volsize;
|
|
uint64_t len;
|
|
unsigned minor = 0;
|
|
int error = 0;
|
|
|
|
ASSERT(MUTEX_HELD(&zvol_state_lock));
|
|
|
|
zv = zvol_find_by_name(name);
|
|
if (zv) {
|
|
error = SET_ERROR(EEXIST);
|
|
goto out;
|
|
}
|
|
|
|
if (ignore_snapdev == B_FALSE) {
|
|
error = __zvol_snapdev_hidden(name);
|
|
if (error)
|
|
goto out;
|
|
}
|
|
|
|
doi = kmem_alloc(sizeof (dmu_object_info_t), KM_SLEEP);
|
|
|
|
error = dmu_objset_own(name, DMU_OST_ZVOL, B_TRUE, zvol_tag, &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;
|
|
|
|
error = zvol_find_minor(&minor);
|
|
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;
|
|
}
|
|
|
|
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);
|
|
queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, zv->zv_queue);
|
|
#ifdef QUEUE_FLAG_NONROT
|
|
queue_flag_set_unlocked(QUEUE_FLAG_NONROT, zv->zv_queue);
|
|
#endif
|
|
#ifdef QUEUE_FLAG_ADD_RANDOM
|
|
queue_flag_clear_unlocked(QUEUE_FLAG_ADD_RANDOM, 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);
|
|
}
|
|
|
|
/*
|
|
* 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, zvol_tag);
|
|
out_doi:
|
|
kmem_free(doi, sizeof (dmu_object_info_t));
|
|
out:
|
|
|
|
if (error == 0) {
|
|
zvol_insert(zv);
|
|
add_disk(zv->zv_disk);
|
|
}
|
|
|
|
return (SET_ERROR(error));
|
|
}
|
|
|
|
/*
|
|
* 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.
|
|
*/
|
|
int
|
|
zvol_create_minor(const char *name)
|
|
{
|
|
int error;
|
|
|
|
mutex_enter(&zvol_state_lock);
|
|
error = __zvol_create_minor(name, B_FALSE);
|
|
mutex_exit(&zvol_state_lock);
|
|
|
|
return (SET_ERROR(error));
|
|
}
|
|
|
|
static int
|
|
__zvol_remove_minor(const char *name)
|
|
{
|
|
zvol_state_t *zv;
|
|
|
|
ASSERT(MUTEX_HELD(&zvol_state_lock));
|
|
|
|
zv = zvol_find_by_name(name);
|
|
if (zv == NULL)
|
|
return (SET_ERROR(ENXIO));
|
|
|
|
if (zv->zv_open_count > 0)
|
|
return (SET_ERROR(EBUSY));
|
|
|
|
zvol_remove(zv);
|
|
zvol_free(zv);
|
|
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Remove a block device minor node for the specified volume.
|
|
*/
|
|
int
|
|
zvol_remove_minor(const char *name)
|
|
{
|
|
int error;
|
|
|
|
mutex_enter(&zvol_state_lock);
|
|
error = __zvol_remove_minor(name);
|
|
mutex_exit(&zvol_state_lock);
|
|
|
|
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(MUTEX_HELD(&zvol_state_lock));
|
|
|
|
strlcpy(zv->zv_name, newname, sizeof (zv->zv_name));
|
|
|
|
/*
|
|
* 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);
|
|
}
|
|
|
|
static int
|
|
zvol_create_minors_cb(const char *dsname, void *arg)
|
|
{
|
|
(void) zvol_create_minor(dsname);
|
|
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Create minors for specified dataset including children and snapshots.
|
|
*/
|
|
int
|
|
zvol_create_minors(const char *name)
|
|
{
|
|
int error = 0;
|
|
|
|
if (!zvol_inhibit_dev)
|
|
error = dmu_objset_find((char *)name, zvol_create_minors_cb,
|
|
NULL, DS_FIND_CHILDREN | DS_FIND_SNAPSHOTS);
|
|
|
|
return (SET_ERROR(error));
|
|
}
|
|
|
|
/*
|
|
* Remove minors for specified dataset including children and snapshots.
|
|
*/
|
|
void
|
|
zvol_remove_minors(const char *name)
|
|
{
|
|
zvol_state_t *zv, *zv_next;
|
|
int namelen = ((name) ? strlen(name) : 0);
|
|
|
|
if (zvol_inhibit_dev)
|
|
return;
|
|
|
|
mutex_enter(&zvol_state_lock);
|
|
|
|
for (zv = list_head(&zvol_state_list); zv != NULL; zv = zv_next) {
|
|
zv_next = list_next(&zvol_state_list, zv);
|
|
|
|
if (name == NULL || strcmp(zv->zv_name, name) == 0 ||
|
|
(strncmp(zv->zv_name, name, namelen) == 0 &&
|
|
zv->zv_name[namelen] == '/')) {
|
|
zvol_remove(zv);
|
|
zvol_free(zv);
|
|
}
|
|
}
|
|
|
|
mutex_exit(&zvol_state_lock);
|
|
}
|
|
|
|
/*
|
|
* Rename minors for specified dataset including children and snapshots.
|
|
*/
|
|
void
|
|
zvol_rename_minors(const char *oldname, const char *newname)
|
|
{
|
|
zvol_state_t *zv, *zv_next;
|
|
int oldnamelen, newnamelen;
|
|
char *name;
|
|
|
|
if (zvol_inhibit_dev)
|
|
return;
|
|
|
|
oldnamelen = strlen(oldname);
|
|
newnamelen = strlen(newname);
|
|
name = kmem_alloc(MAXNAMELEN, KM_SLEEP);
|
|
|
|
mutex_enter(&zvol_state_lock);
|
|
|
|
for (zv = list_head(&zvol_state_list); zv != NULL; zv = zv_next) {
|
|
zv_next = list_next(&zvol_state_list, zv);
|
|
|
|
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] == '@')) {
|
|
snprintf(name, MAXNAMELEN, "%s%c%s", newname,
|
|
zv->zv_name[oldnamelen],
|
|
zv->zv_name + oldnamelen + 1);
|
|
__zvol_rename_minor(zv, name);
|
|
}
|
|
}
|
|
|
|
mutex_exit(&zvol_state_lock);
|
|
|
|
kmem_free(name, MAXNAMELEN);
|
|
}
|
|
|
|
static int
|
|
snapdev_snapshot_changed_cb(const char *dsname, void *arg) {
|
|
uint64_t snapdev = *(uint64_t *) arg;
|
|
|
|
if (strchr(dsname, '@') == NULL)
|
|
return (0);
|
|
|
|
switch (snapdev) {
|
|
case ZFS_SNAPDEV_VISIBLE:
|
|
mutex_enter(&zvol_state_lock);
|
|
(void) __zvol_create_minor(dsname, B_TRUE);
|
|
mutex_exit(&zvol_state_lock);
|
|
break;
|
|
case ZFS_SNAPDEV_HIDDEN:
|
|
(void) zvol_remove_minor(dsname);
|
|
break;
|
|
}
|
|
|
|
return (0);
|
|
}
|
|
|
|
int
|
|
zvol_set_snapdev(const char *dsname, uint64_t snapdev) {
|
|
(void) dmu_objset_find((char *) dsname, snapdev_snapshot_changed_cb,
|
|
&snapdev, DS_FIND_SNAPSHOTS | DS_FIND_CHILDREN);
|
|
/* caller should continue to modify snapdev property */
|
|
return (-1);
|
|
}
|
|
|
|
int
|
|
zvol_init(void)
|
|
{
|
|
int error;
|
|
|
|
list_create(&zvol_state_list, sizeof (zvol_state_t),
|
|
offsetof(zvol_state_t, zv_next));
|
|
|
|
mutex_init(&zvol_state_lock, NULL, MUTEX_DEFAULT, NULL);
|
|
|
|
error = register_blkdev(zvol_major, ZVOL_DRIVER);
|
|
if (error) {
|
|
printk(KERN_INFO "ZFS: register_blkdev() failed %d\n", error);
|
|
goto out;
|
|
}
|
|
|
|
blk_register_region(MKDEV(zvol_major, 0), 1UL << MINORBITS,
|
|
THIS_MODULE, zvol_probe, NULL, NULL);
|
|
|
|
return (0);
|
|
|
|
out:
|
|
mutex_destroy(&zvol_state_lock);
|
|
list_destroy(&zvol_state_list);
|
|
|
|
return (SET_ERROR(error));
|
|
}
|
|
|
|
void
|
|
zvol_fini(void)
|
|
{
|
|
zvol_remove_minors(NULL);
|
|
blk_unregister_region(MKDEV(zvol_major, 0), 1UL << MINORBITS);
|
|
unregister_blkdev(zvol_major, ZVOL_DRIVER);
|
|
mutex_destroy(&zvol_state_lock);
|
|
list_destroy(&zvol_state_list);
|
|
}
|
|
|
|
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_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");
|