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-rw-r--r--uts/common/fs/zfs/zvol.c1894
1 files changed, 1894 insertions, 0 deletions
diff --git a/uts/common/fs/zfs/zvol.c b/uts/common/fs/zfs/zvol.c
new file mode 100644
index 000000000000..47b6c5a87a52
--- /dev/null
+++ b/uts/common/fs/zfs/zvol.c
@@ -0,0 +1,1894 @@
+/*
+ * 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) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
+ */
+
+/* Portions Copyright 2010 Robert Milkowski */
+
+/*
+ * 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/zvol/dsk/<pool_name>/<dataset_name>
+ * /dev/zvol/rdsk/<pool_name>/<dataset_name>
+ *
+ * These links are created by the /dev filesystem (sdev_zvolops.c).
+ * Volumes are persistent through reboot. No user command needs to be
+ * run before opening and using a device.
+ */
+
+#include <sys/types.h>
+#include <sys/param.h>
+#include <sys/errno.h>
+#include <sys/uio.h>
+#include <sys/buf.h>
+#include <sys/modctl.h>
+#include <sys/open.h>
+#include <sys/kmem.h>
+#include <sys/conf.h>
+#include <sys/cmn_err.h>
+#include <sys/stat.h>
+#include <sys/zap.h>
+#include <sys/spa.h>
+#include <sys/zio.h>
+#include <sys/dmu_traverse.h>
+#include <sys/dnode.h>
+#include <sys/dsl_dataset.h>
+#include <sys/dsl_prop.h>
+#include <sys/dkio.h>
+#include <sys/efi_partition.h>
+#include <sys/byteorder.h>
+#include <sys/pathname.h>
+#include <sys/ddi.h>
+#include <sys/sunddi.h>
+#include <sys/crc32.h>
+#include <sys/dirent.h>
+#include <sys/policy.h>
+#include <sys/fs/zfs.h>
+#include <sys/zfs_ioctl.h>
+#include <sys/mkdev.h>
+#include <sys/zil.h>
+#include <sys/refcount.h>
+#include <sys/zfs_znode.h>
+#include <sys/zfs_rlock.h>
+#include <sys/vdev_disk.h>
+#include <sys/vdev_impl.h>
+#include <sys/zvol.h>
+#include <sys/dumphdr.h>
+#include <sys/zil_impl.h>
+
+#include "zfs_namecheck.h"
+
+void *zfsdev_state;
+static char *zvol_tag = "zvol_tag";
+
+#define ZVOL_DUMPSIZE "dumpsize"
+
+/*
+ * This lock protects the zfsdev_state structure from being modified
+ * while it's being used, e.g. an open that comes in before a create
+ * finishes. It also protects temporary opens of the dataset so that,
+ * e.g., an open doesn't get a spurious EBUSY.
+ */
+kmutex_t zfsdev_state_lock;
+static uint32_t zvol_minors;
+
+typedef struct zvol_extent {
+ list_node_t ze_node;
+ dva_t ze_dva; /* dva associated with this extent */
+ uint64_t ze_nblks; /* number of blocks in extent */
+} zvol_extent_t;
+
+/*
+ * The in-core state of each volume.
+ */
+typedef struct zvol_state {
+ char zv_name[MAXPATHLEN]; /* pool/dd name */
+ uint64_t zv_volsize; /* amount of space we advertise */
+ uint64_t zv_volblocksize; /* volume block size */
+ minor_t zv_minor; /* minor number */
+ uint8_t zv_min_bs; /* minimum addressable block shift */
+ uint8_t zv_flags; /* readonly, dumpified, etc. */
+ objset_t *zv_objset; /* objset handle */
+ uint32_t zv_open_count[OTYPCNT]; /* open counts */
+ uint32_t zv_total_opens; /* total open count */
+ zilog_t *zv_zilog; /* ZIL handle */
+ list_t zv_extents; /* List of extents for dump */
+ znode_t zv_znode; /* for range locking */
+ dmu_buf_t *zv_dbuf; /* bonus handle */
+} zvol_state_t;
+
+/*
+ * zvol specific flags
+ */
+#define ZVOL_RDONLY 0x1
+#define ZVOL_DUMPIFIED 0x2
+#define ZVOL_EXCL 0x4
+#define ZVOL_WCE 0x8
+
+/*
+ * zvol maximum transfer in one DMU tx.
+ */
+int zvol_maxphys = DMU_MAX_ACCESS/2;
+
+extern int zfs_set_prop_nvlist(const char *, zprop_source_t,
+ nvlist_t *, nvlist_t **);
+static int zvol_remove_zv(zvol_state_t *);
+static int zvol_get_data(void *arg, lr_write_t *lr, char *buf, zio_t *zio);
+static int zvol_dumpify(zvol_state_t *zv);
+static int zvol_dump_fini(zvol_state_t *zv);
+static int zvol_dump_init(zvol_state_t *zv, boolean_t resize);
+
+static void
+zvol_size_changed(uint64_t volsize, major_t maj, minor_t min)
+{
+ dev_t dev = makedevice(maj, min);
+
+ VERIFY(ddi_prop_update_int64(dev, zfs_dip,
+ "Size", volsize) == DDI_SUCCESS);
+ VERIFY(ddi_prop_update_int64(dev, zfs_dip,
+ "Nblocks", lbtodb(volsize)) == DDI_SUCCESS);
+
+ /* Notify specfs to invalidate the cached size */
+ spec_size_invalidate(dev, VBLK);
+ spec_size_invalidate(dev, VCHR);
+}
+
+int
+zvol_check_volsize(uint64_t volsize, uint64_t blocksize)
+{
+ if (volsize == 0)
+ return (EINVAL);
+
+ if (volsize % blocksize != 0)
+ return (EINVAL);
+
+#ifdef _ILP32
+ if (volsize - 1 > SPEC_MAXOFFSET_T)
+ return (EOVERFLOW);
+#endif
+ return (0);
+}
+
+int
+zvol_check_volblocksize(uint64_t volblocksize)
+{
+ if (volblocksize < SPA_MINBLOCKSIZE ||
+ volblocksize > SPA_MAXBLOCKSIZE ||
+ !ISP2(volblocksize))
+ return (EDOM);
+
+ return (0);
+}
+
+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 (error);
+
+ dsl_prop_nvlist_add_uint64(nv, ZFS_PROP_VOLSIZE, val);
+
+ 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);
+ }
+
+ return (error);
+}
+
+static zvol_state_t *
+zvol_minor_lookup(const char *name)
+{
+ minor_t minor;
+ zvol_state_t *zv;
+
+ ASSERT(MUTEX_HELD(&zfsdev_state_lock));
+
+ for (minor = 1; minor <= ZFSDEV_MAX_MINOR; minor++) {
+ zv = zfsdev_get_soft_state(minor, ZSST_ZVOL);
+ if (zv == NULL)
+ continue;
+ if (strcmp(zv->zv_name, name) == 0)
+ return (zv);
+ }
+
+ return (NULL);
+}
+
+/* extent mapping arg */
+struct maparg {
+ zvol_state_t *ma_zv;
+ uint64_t ma_blks;
+};
+
+/*ARGSUSED*/
+static int
+zvol_map_block(spa_t *spa, zilog_t *zilog, const blkptr_t *bp, arc_buf_t *pbuf,
+ const zbookmark_t *zb, const dnode_phys_t *dnp, void *arg)
+{
+ struct maparg *ma = arg;
+ zvol_extent_t *ze;
+ int bs = ma->ma_zv->zv_volblocksize;
+
+ if (bp == NULL || zb->zb_object != ZVOL_OBJ || zb->zb_level != 0)
+ return (0);
+
+ VERIFY3U(ma->ma_blks, ==, zb->zb_blkid);
+ ma->ma_blks++;
+
+ /* Abort immediately if we have encountered gang blocks */
+ if (BP_IS_GANG(bp))
+ return (EFRAGS);
+
+ /*
+ * See if the block is at the end of the previous extent.
+ */
+ ze = list_tail(&ma->ma_zv->zv_extents);
+ if (ze &&
+ DVA_GET_VDEV(BP_IDENTITY(bp)) == DVA_GET_VDEV(&ze->ze_dva) &&
+ DVA_GET_OFFSET(BP_IDENTITY(bp)) ==
+ DVA_GET_OFFSET(&ze->ze_dva) + ze->ze_nblks * bs) {
+ ze->ze_nblks++;
+ return (0);
+ }
+
+ dprintf_bp(bp, "%s", "next blkptr:");
+
+ /* start a new extent */
+ ze = kmem_zalloc(sizeof (zvol_extent_t), KM_SLEEP);
+ ze->ze_dva = bp->blk_dva[0]; /* structure assignment */
+ ze->ze_nblks = 1;
+ list_insert_tail(&ma->ma_zv->zv_extents, ze);
+ return (0);
+}
+
+static void
+zvol_free_extents(zvol_state_t *zv)
+{
+ zvol_extent_t *ze;
+
+ while (ze = list_head(&zv->zv_extents)) {
+ list_remove(&zv->zv_extents, ze);
+ kmem_free(ze, sizeof (zvol_extent_t));
+ }
+}
+
+static int
+zvol_get_lbas(zvol_state_t *zv)
+{
+ objset_t *os = zv->zv_objset;
+ struct maparg ma;
+ int err;
+
+ ma.ma_zv = zv;
+ ma.ma_blks = 0;
+ zvol_free_extents(zv);
+
+ /* commit any in-flight changes before traversing the dataset */
+ txg_wait_synced(dmu_objset_pool(os), 0);
+ err = traverse_dataset(dmu_objset_ds(os), 0,
+ TRAVERSE_PRE | TRAVERSE_PREFETCH_METADATA, zvol_map_block, &ma);
+ if (err || ma.ma_blks != (zv->zv_volsize / zv->zv_volblocksize)) {
+ zvol_free_extents(zv);
+ return (err ? err : EIO);
+ }
+
+ return (0);
+}
+
+/* ARGSUSED */
+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);
+}
+
+/*
+ * 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 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);
+}
+
+/* ARGSUSED */
+static int
+zvol_replay_err(zvol_state_t *zv, lr_t *lr, boolean_t byteswap)
+{
+ return (ENOTSUP);
+}
+
+/*
+ * Callback vectors for replaying records.
+ * Only TX_WRITE is needed for zvol.
+ */
+zil_replay_func_t *zvol_replay_vector[TX_MAX_TYPE] = {
+ zvol_replay_err, /* 0 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_err, /* TX_TRUNCATE */
+ zvol_replay_err, /* TX_SETATTR */
+ zvol_replay_err, /* TX_ACL */
+ zvol_replay_err, /* TX_CREATE_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 */
+};
+
+int
+zvol_name2minor(const char *name, minor_t *minor)
+{
+ zvol_state_t *zv;
+
+ mutex_enter(&zfsdev_state_lock);
+ zv = zvol_minor_lookup(name);
+ if (minor && zv)
+ *minor = zv->zv_minor;
+ mutex_exit(&zfsdev_state_lock);
+ return (zv ? 0 : -1);
+}
+
+/*
+ * Create a minor node (plus a whole lot more) for the specified volume.
+ */
+int
+zvol_create_minor(const char *name)
+{
+ zfs_soft_state_t *zs;
+ zvol_state_t *zv;
+ objset_t *os;
+ dmu_object_info_t doi;
+ minor_t minor = 0;
+ char chrbuf[30], blkbuf[30];
+ int error;
+
+ mutex_enter(&zfsdev_state_lock);
+
+ if (zvol_minor_lookup(name) != NULL) {
+ mutex_exit(&zfsdev_state_lock);
+ return (EEXIST);
+ }
+
+ /* lie and say we're read-only */
+ error = dmu_objset_own(name, DMU_OST_ZVOL, B_TRUE, FTAG, &os);
+
+ if (error) {
+ mutex_exit(&zfsdev_state_lock);
+ return (error);
+ }
+
+ if ((minor = zfsdev_minor_alloc()) == 0) {
+ dmu_objset_disown(os, FTAG);
+ mutex_exit(&zfsdev_state_lock);
+ return (ENXIO);
+ }
+
+ if (ddi_soft_state_zalloc(zfsdev_state, minor) != DDI_SUCCESS) {
+ dmu_objset_disown(os, FTAG);
+ mutex_exit(&zfsdev_state_lock);
+ return (EAGAIN);
+ }
+ (void) ddi_prop_update_string(minor, zfs_dip, ZVOL_PROP_NAME,
+ (char *)name);
+
+ (void) snprintf(chrbuf, sizeof (chrbuf), "%u,raw", minor);
+
+ if (ddi_create_minor_node(zfs_dip, chrbuf, S_IFCHR,
+ minor, DDI_PSEUDO, 0) == DDI_FAILURE) {
+ ddi_soft_state_free(zfsdev_state, minor);
+ dmu_objset_disown(os, FTAG);
+ mutex_exit(&zfsdev_state_lock);
+ return (EAGAIN);
+ }
+
+ (void) snprintf(blkbuf, sizeof (blkbuf), "%u", minor);
+
+ if (ddi_create_minor_node(zfs_dip, blkbuf, S_IFBLK,
+ minor, DDI_PSEUDO, 0) == DDI_FAILURE) {
+ ddi_remove_minor_node(zfs_dip, chrbuf);
+ ddi_soft_state_free(zfsdev_state, minor);
+ dmu_objset_disown(os, FTAG);
+ mutex_exit(&zfsdev_state_lock);
+ return (EAGAIN);
+ }
+
+ zs = ddi_get_soft_state(zfsdev_state, minor);
+ zs->zss_type = ZSST_ZVOL;
+ zv = zs->zss_data = kmem_zalloc(sizeof (zvol_state_t), KM_SLEEP);
+ (void) strlcpy(zv->zv_name, name, MAXPATHLEN);
+ zv->zv_min_bs = DEV_BSHIFT;
+ zv->zv_minor = minor;
+ zv->zv_objset = os;
+ if (dmu_objset_is_snapshot(os) || !spa_writeable(dmu_objset_spa(os)))
+ zv->zv_flags |= ZVOL_RDONLY;
+ 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));
+ list_create(&zv->zv_extents, sizeof (zvol_extent_t),
+ offsetof(zvol_extent_t, ze_node));
+ /* get and cache the blocksize */
+ error = dmu_object_info(os, ZVOL_OBJ, &doi);
+ ASSERT(error == 0);
+ zv->zv_volblocksize = doi.doi_data_block_size;
+
+ 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);
+ }
+ dmu_objset_disown(os, FTAG);
+ zv->zv_objset = NULL;
+
+ zvol_minors++;
+
+ mutex_exit(&zfsdev_state_lock);
+
+ return (0);
+}
+
+/*
+ * Remove minor node for the specified volume.
+ */
+static int
+zvol_remove_zv(zvol_state_t *zv)
+{
+ char nmbuf[20];
+ minor_t minor = zv->zv_minor;
+
+ ASSERT(MUTEX_HELD(&zfsdev_state_lock));
+ if (zv->zv_total_opens != 0)
+ return (EBUSY);
+
+ (void) snprintf(nmbuf, sizeof (nmbuf), "%u,raw", minor);
+ ddi_remove_minor_node(zfs_dip, nmbuf);
+
+ (void) snprintf(nmbuf, sizeof (nmbuf), "%u", minor);
+ ddi_remove_minor_node(zfs_dip, nmbuf);
+
+ avl_destroy(&zv->zv_znode.z_range_avl);
+ mutex_destroy(&zv->zv_znode.z_range_lock);
+
+ kmem_free(zv, sizeof (zvol_state_t));
+
+ ddi_soft_state_free(zfsdev_state, minor);
+
+ zvol_minors--;
+ return (0);
+}
+
+int
+zvol_remove_minor(const char *name)
+{
+ zvol_state_t *zv;
+ int rc;
+
+ mutex_enter(&zfsdev_state_lock);
+ if ((zv = zvol_minor_lookup(name)) == NULL) {
+ mutex_exit(&zfsdev_state_lock);
+ return (ENXIO);
+ }
+ rc = zvol_remove_zv(zv);
+ mutex_exit(&zfsdev_state_lock);
+ return (rc);
+}
+
+int
+zvol_first_open(zvol_state_t *zv)
+{
+ objset_t *os;
+ uint64_t volsize;
+ int error;
+ uint64_t readonly;
+
+ /* lie and say we're read-only */
+ error = dmu_objset_own(zv->zv_name, DMU_OST_ZVOL, B_TRUE,
+ zvol_tag, &os);
+ if (error)
+ return (error);
+
+ error = zap_lookup(os, ZVOL_ZAP_OBJ, "size", 8, 1, &volsize);
+ if (error) {
+ ASSERT(error == 0);
+ dmu_objset_disown(os, zvol_tag);
+ return (error);
+ }
+ zv->zv_objset = os;
+ error = dmu_bonus_hold(os, ZVOL_OBJ, zvol_tag, &zv->zv_dbuf);
+ if (error) {
+ dmu_objset_disown(os, zvol_tag);
+ return (error);
+ }
+ zv->zv_volsize = volsize;
+ zv->zv_zilog = zil_open(os, zvol_get_data);
+ zvol_size_changed(zv->zv_volsize, ddi_driver_major(zfs_dip),
+ zv->zv_minor);
+
+ VERIFY(dsl_prop_get_integer(zv->zv_name, "readonly", &readonly,
+ NULL) == 0);
+ if (readonly || dmu_objset_is_snapshot(os) ||
+ !spa_writeable(dmu_objset_spa(os)))
+ zv->zv_flags |= ZVOL_RDONLY;
+ else
+ zv->zv_flags &= ~ZVOL_RDONLY;
+ return (error);
+}
+
+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;
+ dmu_objset_disown(zv->zv_objset, zvol_tag);
+ zv->zv_objset = NULL;
+}
+
+int
+zvol_prealloc(zvol_state_t *zv)
+{
+ objset_t *os = zv->zv_objset;
+ dmu_tx_t *tx;
+ uint64_t refd, avail, usedobjs, availobjs;
+ uint64_t resid = zv->zv_volsize;
+ uint64_t off = 0;
+
+ /* Check the space usage before attempting to allocate the space */
+ dmu_objset_space(os, &refd, &avail, &usedobjs, &availobjs);
+ if (avail < zv->zv_volsize)
+ return (ENOSPC);
+
+ /* Free old extents if they exist */
+ zvol_free_extents(zv);
+
+ while (resid != 0) {
+ int error;
+ uint64_t bytes = MIN(resid, SPA_MAXBLOCKSIZE);
+
+ tx = dmu_tx_create(os);
+ dmu_tx_hold_write(tx, ZVOL_OBJ, off, bytes);
+ error = dmu_tx_assign(tx, TXG_WAIT);
+ if (error) {
+ dmu_tx_abort(tx);
+ (void) dmu_free_long_range(os, ZVOL_OBJ, 0, off);
+ return (error);
+ }
+ dmu_prealloc(os, ZVOL_OBJ, off, bytes, tx);
+ dmu_tx_commit(tx);
+ off += bytes;
+ resid -= bytes;
+ }
+ txg_wait_synced(dmu_objset_pool(os), 0);
+
+ return (0);
+}
+
+int
+zvol_update_volsize(objset_t *os, uint64_t volsize)
+{
+ dmu_tx_t *tx;
+ int error;
+
+ ASSERT(MUTEX_HELD(&zfsdev_state_lock));
+
+ tx = dmu_tx_create(os);
+ dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL);
+ error = dmu_tx_assign(tx, TXG_WAIT);
+ if (error) {
+ dmu_tx_abort(tx);
+ return (error);
+ }
+
+ error = zap_update(os, ZVOL_ZAP_OBJ, "size", 8, 1,
+ &volsize, tx);
+ dmu_tx_commit(tx);
+
+ if (error == 0)
+ error = dmu_free_long_range(os,
+ ZVOL_OBJ, volsize, DMU_OBJECT_END);
+ return (error);
+}
+
+void
+zvol_remove_minors(const char *name)
+{
+ zvol_state_t *zv;
+ char *namebuf;
+ minor_t minor;
+
+ namebuf = kmem_zalloc(strlen(name) + 2, KM_SLEEP);
+ (void) strncpy(namebuf, name, strlen(name));
+ (void) strcat(namebuf, "/");
+ mutex_enter(&zfsdev_state_lock);
+ for (minor = 1; minor <= ZFSDEV_MAX_MINOR; minor++) {
+
+ zv = zfsdev_get_soft_state(minor, ZSST_ZVOL);
+ if (zv == NULL)
+ continue;
+ if (strncmp(namebuf, zv->zv_name, strlen(namebuf)) == 0)
+ (void) zvol_remove_zv(zv);
+ }
+ kmem_free(namebuf, strlen(name) + 2);
+
+ mutex_exit(&zfsdev_state_lock);
+}
+
+int
+zvol_set_volsize(const char *name, major_t maj, uint64_t volsize)
+{
+ zvol_state_t *zv = NULL;
+ objset_t *os;
+ int error;
+ dmu_object_info_t doi;
+ uint64_t old_volsize = 0ULL;
+ uint64_t readonly;
+
+ mutex_enter(&zfsdev_state_lock);
+ zv = zvol_minor_lookup(name);
+ if ((error = dmu_objset_hold(name, FTAG, &os)) != 0) {
+ mutex_exit(&zfsdev_state_lock);
+ return (error);
+ }
+
+ if ((error = dmu_object_info(os, ZVOL_OBJ, &doi)) != 0 ||
+ (error = zvol_check_volsize(volsize,
+ doi.doi_data_block_size)) != 0)
+ goto out;
+
+ VERIFY(dsl_prop_get_integer(name, "readonly", &readonly,
+ NULL) == 0);
+ if (readonly) {
+ error = EROFS;
+ goto out;
+ }
+
+ error = zvol_update_volsize(os, volsize);
+ /*
+ * Reinitialize the dump area to the new size. If we
+ * failed to resize the dump area then restore it back to
+ * its original size.
+ */
+ if (zv && error == 0) {
+ if (zv->zv_flags & ZVOL_DUMPIFIED) {
+ old_volsize = zv->zv_volsize;
+ zv->zv_volsize = volsize;
+ if ((error = zvol_dumpify(zv)) != 0 ||
+ (error = dumpvp_resize()) != 0) {
+ (void) zvol_update_volsize(os, old_volsize);
+ zv->zv_volsize = old_volsize;
+ error = zvol_dumpify(zv);
+ }
+ }
+ if (error == 0) {
+ zv->zv_volsize = volsize;
+ zvol_size_changed(volsize, maj, zv->zv_minor);
+ }
+ }
+
+ /*
+ * Generate a LUN expansion event.
+ */
+ if (zv && error == 0) {
+ sysevent_id_t eid;
+ nvlist_t *attr;
+ char *physpath = kmem_zalloc(MAXPATHLEN, KM_SLEEP);
+
+ (void) snprintf(physpath, MAXPATHLEN, "%s%u", ZVOL_PSEUDO_DEV,
+ zv->zv_minor);
+
+ VERIFY(nvlist_alloc(&attr, NV_UNIQUE_NAME, KM_SLEEP) == 0);
+ VERIFY(nvlist_add_string(attr, DEV_PHYS_PATH, physpath) == 0);
+
+ (void) ddi_log_sysevent(zfs_dip, SUNW_VENDOR, EC_DEV_STATUS,
+ ESC_DEV_DLE, attr, &eid, DDI_SLEEP);
+
+ nvlist_free(attr);
+ kmem_free(physpath, MAXPATHLEN);
+ }
+
+out:
+ dmu_objset_rele(os, FTAG);
+
+ mutex_exit(&zfsdev_state_lock);
+
+ return (error);
+}
+
+/*ARGSUSED*/
+int
+zvol_open(dev_t *devp, int flag, int otyp, cred_t *cr)
+{
+ zvol_state_t *zv;
+ int err = 0;
+
+ mutex_enter(&zfsdev_state_lock);
+
+ zv = zfsdev_get_soft_state(getminor(*devp), ZSST_ZVOL);
+ if (zv == NULL) {
+ mutex_exit(&zfsdev_state_lock);
+ return (ENXIO);
+ }
+
+ if (zv->zv_total_opens == 0)
+ err = zvol_first_open(zv);
+ if (err) {
+ mutex_exit(&zfsdev_state_lock);
+ return (err);
+ }
+ if ((flag & FWRITE) && (zv->zv_flags & ZVOL_RDONLY)) {
+ err = EROFS;
+ goto out;
+ }
+ if (zv->zv_flags & ZVOL_EXCL) {
+ err = EBUSY;
+ goto out;
+ }
+ if (flag & FEXCL) {
+ if (zv->zv_total_opens != 0) {
+ err = EBUSY;
+ goto out;
+ }
+ zv->zv_flags |= ZVOL_EXCL;
+ }
+
+ if (zv->zv_open_count[otyp] == 0 || otyp == OTYP_LYR) {
+ zv->zv_open_count[otyp]++;
+ zv->zv_total_opens++;
+ }
+ mutex_exit(&zfsdev_state_lock);
+
+ return (err);
+out:
+ if (zv->zv_total_opens == 0)
+ zvol_last_close(zv);
+ mutex_exit(&zfsdev_state_lock);
+ return (err);
+}
+
+/*ARGSUSED*/
+int
+zvol_close(dev_t dev, int flag, int otyp, cred_t *cr)
+{
+ minor_t minor = getminor(dev);
+ zvol_state_t *zv;
+ int error = 0;
+
+ mutex_enter(&zfsdev_state_lock);
+
+ zv = zfsdev_get_soft_state(minor, ZSST_ZVOL);
+ if (zv == NULL) {
+ mutex_exit(&zfsdev_state_lock);
+ return (ENXIO);
+ }
+
+ if (zv->zv_flags & ZVOL_EXCL) {
+ ASSERT(zv->zv_total_opens == 1);
+ zv->zv_flags &= ~ZVOL_EXCL;
+ }
+
+ /*
+ * If the open count is zero, this is a spurious close.
+ * That indicates a bug in the kernel / DDI framework.
+ */
+ ASSERT(zv->zv_open_count[otyp] != 0);
+ ASSERT(zv->zv_total_opens != 0);
+
+ /*
+ * You may get multiple opens, but only one close.
+ */
+ zv->zv_open_count[otyp]--;
+ zv->zv_total_opens--;
+
+ if (zv->zv_total_opens == 0)
+ zvol_last_close(zv);
+
+ mutex_exit(&zfsdev_state_lock);
+ return (error);
+}
+
+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; /* length of user data */
+ blkptr_t *bp = &lr->lr_blkptr;
+ dmu_buf_t *db;
+ zgd_t *zgd;
+ int error;
+
+ ASSERT(zio != NULL);
+ ASSERT(size != 0);
+
+ zgd = 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(offset, size);
+ error = dmu_buf_hold(os, object, offset, zgd, &db,
+ DMU_READ_NO_PREFETCH);
+ if (error == 0) {
+ zgd->zgd_db = db;
+ zgd->zgd_bp = bp;
+
+ 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 (error);
+}
+
+/*
+ * 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, offset_t off, ssize_t resid,
+ boolean_t 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 (resid) {
+ 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
+ * upto DMU_MAX_ACCESS/2 (5MB) writes.
+ */
+ if (blocksize > immediate_write_sz && !slogging &&
+ resid >= blocksize && off % blocksize == 0) {
+ write_state = WR_INDIRECT; /* uses dmu_sync */
+ len = blocksize;
+ } else if (sync) {
+ write_state = WR_COPIED;
+ len = MIN(ZIL_MAX_LOG_DATA, resid);
+ } else {
+ write_state = WR_NEED_COPY;
+ len = MIN(ZIL_MAX_LOG_DATA, resid);
+ }
+
+ 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, off, 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 = off;
+ lr->lr_length = len;
+ lr->lr_blkoff = 0;
+ BP_ZERO(&lr->lr_blkptr);
+
+ itx->itx_private = zv;
+ itx->itx_sync = sync;
+
+ zil_itx_assign(zilog, itx, tx);
+
+ off += len;
+ resid -= len;
+ }
+}
+
+static int
+zvol_dumpio_vdev(vdev_t *vd, void *addr, uint64_t offset, uint64_t size,
+ boolean_t doread, boolean_t isdump)
+{
+ vdev_disk_t *dvd;
+ int c;
+ int numerrors = 0;
+
+ for (c = 0; c < vd->vdev_children; c++) {
+ ASSERT(vd->vdev_ops == &vdev_mirror_ops ||
+ vd->vdev_ops == &vdev_replacing_ops ||
+ vd->vdev_ops == &vdev_spare_ops);
+ int err = zvol_dumpio_vdev(vd->vdev_child[c],
+ addr, offset, size, doread, isdump);
+ if (err != 0) {
+ numerrors++;
+ } else if (doread) {
+ break;
+ }
+ }
+
+ if (!vd->vdev_ops->vdev_op_leaf)
+ return (numerrors < vd->vdev_children ? 0 : EIO);
+
+ if (doread && !vdev_readable(vd))
+ return (EIO);
+ else if (!doread && !vdev_writeable(vd))
+ return (EIO);
+
+ dvd = vd->vdev_tsd;
+ ASSERT3P(dvd, !=, NULL);
+ offset += VDEV_LABEL_START_SIZE;
+
+ if (ddi_in_panic() || isdump) {
+ ASSERT(!doread);
+ if (doread)
+ return (EIO);
+ return (ldi_dump(dvd->vd_lh, addr, lbtodb(offset),
+ lbtodb(size)));
+ } else {
+ return (vdev_disk_physio(dvd->vd_lh, addr, size, offset,
+ doread ? B_READ : B_WRITE));
+ }
+}
+
+static int
+zvol_dumpio(zvol_state_t *zv, void *addr, uint64_t offset, uint64_t size,
+ boolean_t doread, boolean_t isdump)
+{
+ vdev_t *vd;
+ int error;
+ zvol_extent_t *ze;
+ spa_t *spa = dmu_objset_spa(zv->zv_objset);
+
+ /* Must be sector aligned, and not stradle a block boundary. */
+ if (P2PHASE(offset, DEV_BSIZE) || P2PHASE(size, DEV_BSIZE) ||
+ P2BOUNDARY(offset, size, zv->zv_volblocksize)) {
+ return (EINVAL);
+ }
+ ASSERT(size <= zv->zv_volblocksize);
+
+ /* Locate the extent this belongs to */
+ ze = list_head(&zv->zv_extents);
+ while (offset >= ze->ze_nblks * zv->zv_volblocksize) {
+ offset -= ze->ze_nblks * zv->zv_volblocksize;
+ ze = list_next(&zv->zv_extents, ze);
+ }
+
+ if (!ddi_in_panic())
+ spa_config_enter(spa, SCL_STATE, FTAG, RW_READER);
+
+ vd = vdev_lookup_top(spa, DVA_GET_VDEV(&ze->ze_dva));
+ offset += DVA_GET_OFFSET(&ze->ze_dva);
+ error = zvol_dumpio_vdev(vd, addr, offset, size, doread, isdump);
+
+ if (!ddi_in_panic())
+ spa_config_exit(spa, SCL_STATE, FTAG);
+
+ return (error);
+}
+
+int
+zvol_strategy(buf_t *bp)
+{
+ zfs_soft_state_t *zs = NULL;
+ zvol_state_t *zv;
+ uint64_t off, volsize;
+ size_t resid;
+ char *addr;
+ objset_t *os;
+ rl_t *rl;
+ int error = 0;
+ boolean_t doread = bp->b_flags & B_READ;
+ boolean_t is_dump;
+ boolean_t sync;
+
+ if (getminor(bp->b_edev) == 0) {
+ error = EINVAL;
+ } else {
+ zs = ddi_get_soft_state(zfsdev_state, getminor(bp->b_edev));
+ if (zs == NULL)
+ error = ENXIO;
+ else if (zs->zss_type != ZSST_ZVOL)
+ error = EINVAL;
+ }
+
+ if (error) {
+ bioerror(bp, error);
+ biodone(bp);
+ return (0);
+ }
+
+ zv = zs->zss_data;
+
+ if (!(bp->b_flags & B_READ) && (zv->zv_flags & ZVOL_RDONLY)) {
+ bioerror(bp, EROFS);
+ biodone(bp);
+ return (0);
+ }
+
+ off = ldbtob(bp->b_blkno);
+ volsize = zv->zv_volsize;
+
+ os = zv->zv_objset;
+ ASSERT(os != NULL);
+
+ bp_mapin(bp);
+ addr = bp->b_un.b_addr;
+ resid = bp->b_bcount;
+
+ if (resid > 0 && (off < 0 || off >= volsize)) {
+ bioerror(bp, EIO);
+ biodone(bp);
+ return (0);
+ }
+
+ is_dump = zv->zv_flags & ZVOL_DUMPIFIED;
+ sync = ((!(bp->b_flags & B_ASYNC) &&
+ !(zv->zv_flags & ZVOL_WCE)) ||
+ (zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS)) &&
+ !doread && !is_dump;
+
+ /*
+ * There must be no buffer changes when doing a dmu_sync() because
+ * we can't change the data whilst calculating the checksum.
+ */
+ rl = zfs_range_lock(&zv->zv_znode, off, resid,
+ doread ? RL_READER : RL_WRITER);
+
+ while (resid != 0 && off < volsize) {
+ size_t size = MIN(resid, zvol_maxphys);
+ if (is_dump) {
+ size = MIN(size, P2END(off, zv->zv_volblocksize) - off);
+ error = zvol_dumpio(zv, addr, off, size,
+ doread, B_FALSE);
+ } else if (doread) {
+ error = dmu_read(os, ZVOL_OBJ, off, size, addr,
+ DMU_READ_PREFETCH);
+ } else {
+ dmu_tx_t *tx = dmu_tx_create(os);
+ dmu_tx_hold_write(tx, ZVOL_OBJ, off, size);
+ error = dmu_tx_assign(tx, TXG_WAIT);
+ if (error) {
+ dmu_tx_abort(tx);
+ } else {
+ dmu_write(os, ZVOL_OBJ, off, size, addr, tx);
+ zvol_log_write(zv, tx, off, size, sync);
+ dmu_tx_commit(tx);
+ }
+ }
+ if (error) {
+ /* convert checksum errors into IO errors */
+ if (error == ECKSUM)
+ error = EIO;
+ break;
+ }
+ off += size;
+ addr += size;
+ resid -= size;
+ }
+ zfs_range_unlock(rl);
+
+ if ((bp->b_resid = resid) == bp->b_bcount)
+ bioerror(bp, off > volsize ? EINVAL : error);
+
+ if (sync)
+ zil_commit(zv->zv_zilog, ZVOL_OBJ);
+ biodone(bp);
+
+ return (0);
+}
+
+/*
+ * Set the buffer count to the zvol maximum transfer.
+ * Using our own routine instead of the default minphys()
+ * means that for larger writes we write bigger buffers on X86
+ * (128K instead of 56K) and flush the disk write cache less often
+ * (every zvol_maxphys - currently 1MB) instead of minphys (currently
+ * 56K on X86 and 128K on sparc).
+ */
+void
+zvol_minphys(struct buf *bp)
+{
+ if (bp->b_bcount > zvol_maxphys)
+ bp->b_bcount = zvol_maxphys;
+}
+
+int
+zvol_dump(dev_t dev, caddr_t addr, daddr_t blkno, int nblocks)
+{
+ minor_t minor = getminor(dev);
+ zvol_state_t *zv;
+ int error = 0;
+ uint64_t size;
+ uint64_t boff;
+ uint64_t resid;
+
+ zv = zfsdev_get_soft_state(minor, ZSST_ZVOL);
+ if (zv == NULL)
+ return (ENXIO);
+
+ boff = ldbtob(blkno);
+ resid = ldbtob(nblocks);
+
+ VERIFY3U(boff + resid, <=, zv->zv_volsize);
+
+ while (resid) {
+ size = MIN(resid, P2END(boff, zv->zv_volblocksize) - boff);
+ error = zvol_dumpio(zv, addr, boff, size, B_FALSE, B_TRUE);
+ if (error)
+ break;
+ boff += size;
+ addr += size;
+ resid -= size;
+ }
+
+ return (error);
+}
+
+/*ARGSUSED*/
+int
+zvol_read(dev_t dev, uio_t *uio, cred_t *cr)
+{
+ minor_t minor = getminor(dev);
+ zvol_state_t *zv;
+ uint64_t volsize;
+ rl_t *rl;
+ int error = 0;
+
+ zv = zfsdev_get_soft_state(minor, ZSST_ZVOL);
+ if (zv == NULL)
+ return (ENXIO);
+
+ volsize = zv->zv_volsize;
+ if (uio->uio_resid > 0 &&
+ (uio->uio_loffset < 0 || uio->uio_loffset >= volsize))
+ return (EIO);
+
+ if (zv->zv_flags & ZVOL_DUMPIFIED) {
+ error = physio(zvol_strategy, NULL, dev, B_READ,
+ zvol_minphys, uio);
+ return (error);
+ }
+
+ rl = zfs_range_lock(&zv->zv_znode, uio->uio_loffset, uio->uio_resid,
+ RL_READER);
+ 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(zv->zv_objset, ZVOL_OBJ, uio, bytes);
+ if (error) {
+ /* convert checksum errors into IO errors */
+ if (error == ECKSUM)
+ error = EIO;
+ break;
+ }
+ }
+ zfs_range_unlock(rl);
+ return (error);
+}
+
+/*ARGSUSED*/
+int
+zvol_write(dev_t dev, uio_t *uio, cred_t *cr)
+{
+ minor_t minor = getminor(dev);
+ zvol_state_t *zv;
+ uint64_t volsize;
+ rl_t *rl;
+ int error = 0;
+ boolean_t sync;
+
+ zv = zfsdev_get_soft_state(minor, ZSST_ZVOL);
+ if (zv == NULL)
+ return (ENXIO);
+
+ volsize = zv->zv_volsize;
+ if (uio->uio_resid > 0 &&
+ (uio->uio_loffset < 0 || uio->uio_loffset >= volsize))
+ return (EIO);
+
+ if (zv->zv_flags & ZVOL_DUMPIFIED) {
+ error = physio(zvol_strategy, NULL, dev, B_WRITE,
+ zvol_minphys, uio);
+ return (error);
+ }
+
+ sync = !(zv->zv_flags & ZVOL_WCE) ||
+ (zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS);
+
+ rl = zfs_range_lock(&zv->zv_znode, uio->uio_loffset, uio->uio_resid,
+ RL_WRITER);
+ 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);
+ error = dmu_tx_assign(tx, TXG_WAIT);
+ if (error) {
+ dmu_tx_abort(tx);
+ break;
+ }
+ error = dmu_write_uio_dbuf(zv->zv_dbuf, uio, bytes, tx);
+ if (error == 0)
+ zvol_log_write(zv, tx, off, bytes, sync);
+ dmu_tx_commit(tx);
+
+ if (error)
+ break;
+ }
+ zfs_range_unlock(rl);
+ if (sync)
+ zil_commit(zv->zv_zilog, ZVOL_OBJ);
+ return (error);
+}
+
+int
+zvol_getefi(void *arg, int flag, uint64_t vs, uint8_t bs)
+{
+ struct uuid uuid = EFI_RESERVED;
+ efi_gpe_t gpe = { 0 };
+ uint32_t crc;
+ dk_efi_t efi;
+ int length;
+ char *ptr;
+
+ if (ddi_copyin(arg, &efi, sizeof (dk_efi_t), flag))
+ return (EFAULT);
+ ptr = (char *)(uintptr_t)efi.dki_data_64;
+ length = efi.dki_length;
+ /*
+ * Some clients may attempt to request a PMBR for the
+ * zvol. Currently this interface will return EINVAL to
+ * such requests. These requests could be supported by
+ * adding a check for lba == 0 and consing up an appropriate
+ * PMBR.
+ */
+ if (efi.dki_lba < 1 || efi.dki_lba > 2 || length <= 0)
+ return (EINVAL);
+
+ gpe.efi_gpe_StartingLBA = LE_64(34ULL);
+ gpe.efi_gpe_EndingLBA = LE_64((vs >> bs) - 1);
+ UUID_LE_CONVERT(gpe.efi_gpe_PartitionTypeGUID, uuid);
+
+ if (efi.dki_lba == 1) {
+ efi_gpt_t gpt = { 0 };
+
+ gpt.efi_gpt_Signature = LE_64(EFI_SIGNATURE);
+ gpt.efi_gpt_Revision = LE_32(EFI_VERSION_CURRENT);
+ gpt.efi_gpt_HeaderSize = LE_32(sizeof (gpt));
+ gpt.efi_gpt_MyLBA = LE_64(1ULL);
+ gpt.efi_gpt_FirstUsableLBA = LE_64(34ULL);
+ gpt.efi_gpt_LastUsableLBA = LE_64((vs >> bs) - 1);
+ gpt.efi_gpt_PartitionEntryLBA = LE_64(2ULL);
+ gpt.efi_gpt_NumberOfPartitionEntries = LE_32(1);
+ gpt.efi_gpt_SizeOfPartitionEntry =
+ LE_32(sizeof (efi_gpe_t));
+ CRC32(crc, &gpe, sizeof (gpe), -1U, crc32_table);
+ gpt.efi_gpt_PartitionEntryArrayCRC32 = LE_32(~crc);
+ CRC32(crc, &gpt, sizeof (gpt), -1U, crc32_table);
+ gpt.efi_gpt_HeaderCRC32 = LE_32(~crc);
+ if (ddi_copyout(&gpt, ptr, MIN(sizeof (gpt), length),
+ flag))
+ return (EFAULT);
+ ptr += sizeof (gpt);
+ length -= sizeof (gpt);
+ }
+ if (length > 0 && ddi_copyout(&gpe, ptr, MIN(sizeof (gpe),
+ length), flag))
+ return (EFAULT);
+ return (0);
+}
+
+/*
+ * BEGIN entry points to allow external callers access to the volume.
+ */
+/*
+ * Return the volume parameters needed for access from an external caller.
+ * These values are invariant as long as the volume is held open.
+ */
+int
+zvol_get_volume_params(minor_t minor, uint64_t *blksize,
+ uint64_t *max_xfer_len, void **minor_hdl, void **objset_hdl, void **zil_hdl,
+ void **rl_hdl, void **bonus_hdl)
+{
+ zvol_state_t *zv;
+
+ zv = zfsdev_get_soft_state(minor, ZSST_ZVOL);
+ if (zv == NULL)
+ return (ENXIO);
+ if (zv->zv_flags & ZVOL_DUMPIFIED)
+ return (ENXIO);
+
+ ASSERT(blksize && max_xfer_len && minor_hdl &&
+ objset_hdl && zil_hdl && rl_hdl && bonus_hdl);
+
+ *blksize = zv->zv_volblocksize;
+ *max_xfer_len = (uint64_t)zvol_maxphys;
+ *minor_hdl = zv;
+ *objset_hdl = zv->zv_objset;
+ *zil_hdl = zv->zv_zilog;
+ *rl_hdl = &zv->zv_znode;
+ *bonus_hdl = zv->zv_dbuf;
+ return (0);
+}
+
+/*
+ * Return the current volume size to an external caller.
+ * The size can change while the volume is open.
+ */
+uint64_t
+zvol_get_volume_size(void *minor_hdl)
+{
+ zvol_state_t *zv = minor_hdl;
+
+ return (zv->zv_volsize);
+}
+
+/*
+ * Return the current WCE setting to an external caller.
+ * The WCE setting can change while the volume is open.
+ */
+int
+zvol_get_volume_wce(void *minor_hdl)
+{
+ zvol_state_t *zv = minor_hdl;
+
+ return ((zv->zv_flags & ZVOL_WCE) ? 1 : 0);
+}
+
+/*
+ * Entry point for external callers to zvol_log_write
+ */
+void
+zvol_log_write_minor(void *minor_hdl, dmu_tx_t *tx, offset_t off, ssize_t resid,
+ boolean_t sync)
+{
+ zvol_state_t *zv = minor_hdl;
+
+ zvol_log_write(zv, tx, off, resid, sync);
+}
+/*
+ * END entry points to allow external callers access to the volume.
+ */
+
+/*
+ * Dirtbag ioctls to support mkfs(1M) for UFS filesystems. See dkio(7I).
+ */
+/*ARGSUSED*/
+int
+zvol_ioctl(dev_t dev, int cmd, intptr_t arg, int flag, cred_t *cr, int *rvalp)
+{
+ zvol_state_t *zv;
+ struct dk_cinfo dki;
+ struct dk_minfo dkm;
+ struct dk_callback *dkc;
+ int error = 0;
+ rl_t *rl;
+
+ mutex_enter(&zfsdev_state_lock);
+
+ zv = zfsdev_get_soft_state(getminor(dev), ZSST_ZVOL);
+
+ if (zv == NULL) {
+ mutex_exit(&zfsdev_state_lock);
+ return (ENXIO);
+ }
+ ASSERT(zv->zv_total_opens > 0);
+
+ switch (cmd) {
+
+ case DKIOCINFO:
+ bzero(&dki, sizeof (dki));
+ (void) strcpy(dki.dki_cname, "zvol");
+ (void) strcpy(dki.dki_dname, "zvol");
+ dki.dki_ctype = DKC_UNKNOWN;
+ dki.dki_unit = getminor(dev);
+ dki.dki_maxtransfer = 1 << (SPA_MAXBLOCKSHIFT - zv->zv_min_bs);
+ mutex_exit(&zfsdev_state_lock);
+ if (ddi_copyout(&dki, (void *)arg, sizeof (dki), flag))
+ error = EFAULT;
+ return (error);
+
+ case DKIOCGMEDIAINFO:
+ bzero(&dkm, sizeof (dkm));
+ dkm.dki_lbsize = 1U << zv->zv_min_bs;
+ dkm.dki_capacity = zv->zv_volsize >> zv->zv_min_bs;
+ dkm.dki_media_type = DK_UNKNOWN;
+ mutex_exit(&zfsdev_state_lock);
+ if (ddi_copyout(&dkm, (void *)arg, sizeof (dkm), flag))
+ error = EFAULT;
+ return (error);
+
+ case DKIOCGETEFI:
+ {
+ uint64_t vs = zv->zv_volsize;
+ uint8_t bs = zv->zv_min_bs;
+
+ mutex_exit(&zfsdev_state_lock);
+ error = zvol_getefi((void *)arg, flag, vs, bs);
+ return (error);
+ }
+
+ case DKIOCFLUSHWRITECACHE:
+ dkc = (struct dk_callback *)arg;
+ mutex_exit(&zfsdev_state_lock);
+ zil_commit(zv->zv_zilog, ZVOL_OBJ);
+ if ((flag & FKIOCTL) && dkc != NULL && dkc->dkc_callback) {
+ (*dkc->dkc_callback)(dkc->dkc_cookie, error);
+ error = 0;
+ }
+ return (error);
+
+ case DKIOCGETWCE:
+ {
+ int wce = (zv->zv_flags & ZVOL_WCE) ? 1 : 0;
+ if (ddi_copyout(&wce, (void *)arg, sizeof (int),
+ flag))
+ error = EFAULT;
+ break;
+ }
+ case DKIOCSETWCE:
+ {
+ int wce;
+ if (ddi_copyin((void *)arg, &wce, sizeof (int),
+ flag)) {
+ error = EFAULT;
+ break;
+ }
+ if (wce) {
+ zv->zv_flags |= ZVOL_WCE;
+ mutex_exit(&zfsdev_state_lock);
+ } else {
+ zv->zv_flags &= ~ZVOL_WCE;
+ mutex_exit(&zfsdev_state_lock);
+ zil_commit(zv->zv_zilog, ZVOL_OBJ);
+ }
+ return (0);
+ }
+
+ case DKIOCGGEOM:
+ case DKIOCGVTOC:
+ /*
+ * commands using these (like prtvtoc) expect ENOTSUP
+ * since we're emulating an EFI label
+ */
+ error = ENOTSUP;
+ break;
+
+ case DKIOCDUMPINIT:
+ rl = zfs_range_lock(&zv->zv_znode, 0, zv->zv_volsize,
+ RL_WRITER);
+ error = zvol_dumpify(zv);
+ zfs_range_unlock(rl);
+ break;
+
+ case DKIOCDUMPFINI:
+ if (!(zv->zv_flags & ZVOL_DUMPIFIED))
+ break;
+ rl = zfs_range_lock(&zv->zv_znode, 0, zv->zv_volsize,
+ RL_WRITER);
+ error = zvol_dump_fini(zv);
+ zfs_range_unlock(rl);
+ break;
+
+ default:
+ error = ENOTTY;
+ break;
+
+ }
+ mutex_exit(&zfsdev_state_lock);
+ return (error);
+}
+
+int
+zvol_busy(void)
+{
+ return (zvol_minors != 0);
+}
+
+void
+zvol_init(void)
+{
+ VERIFY(ddi_soft_state_init(&zfsdev_state, sizeof (zfs_soft_state_t),
+ 1) == 0);
+ mutex_init(&zfsdev_state_lock, NULL, MUTEX_DEFAULT, NULL);
+}
+
+void
+zvol_fini(void)
+{
+ mutex_destroy(&zfsdev_state_lock);
+ ddi_soft_state_fini(&zfsdev_state);
+}
+
+static int
+zvol_dump_init(zvol_state_t *zv, boolean_t resize)
+{
+ dmu_tx_t *tx;
+ int error = 0;
+ objset_t *os = zv->zv_objset;
+ nvlist_t *nv = NULL;
+ uint64_t version = spa_version(dmu_objset_spa(zv->zv_objset));
+
+ ASSERT(MUTEX_HELD(&zfsdev_state_lock));
+ error = dmu_free_long_range(zv->zv_objset, ZVOL_OBJ, 0,
+ DMU_OBJECT_END);
+ /* wait for dmu_free_long_range to actually free the blocks */
+ txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0);
+
+ tx = dmu_tx_create(os);
+ dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL);
+ dmu_tx_hold_bonus(tx, ZVOL_OBJ);
+ error = dmu_tx_assign(tx, TXG_WAIT);
+ if (error) {
+ dmu_tx_abort(tx);
+ return (error);
+ }
+
+ /*
+ * If we are resizing the dump device then we only need to
+ * update the refreservation to match the newly updated
+ * zvolsize. Otherwise, we save off the original state of the
+ * zvol so that we can restore them if the zvol is ever undumpified.
+ */
+ if (resize) {
+ error = zap_update(os, ZVOL_ZAP_OBJ,
+ zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1,
+ &zv->zv_volsize, tx);
+ } else {
+ uint64_t checksum, compress, refresrv, vbs, dedup;
+
+ error = dsl_prop_get_integer(zv->zv_name,
+ zfs_prop_to_name(ZFS_PROP_COMPRESSION), &compress, NULL);
+ error = error ? error : dsl_prop_get_integer(zv->zv_name,
+ zfs_prop_to_name(ZFS_PROP_CHECKSUM), &checksum, NULL);
+ error = error ? error : dsl_prop_get_integer(zv->zv_name,
+ zfs_prop_to_name(ZFS_PROP_REFRESERVATION), &refresrv, NULL);
+ error = error ? error : dsl_prop_get_integer(zv->zv_name,
+ zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), &vbs, NULL);
+ if (version >= SPA_VERSION_DEDUP) {
+ error = error ? error :
+ dsl_prop_get_integer(zv->zv_name,
+ zfs_prop_to_name(ZFS_PROP_DEDUP), &dedup, NULL);
+ }
+
+ error = error ? error : zap_update(os, ZVOL_ZAP_OBJ,
+ zfs_prop_to_name(ZFS_PROP_COMPRESSION), 8, 1,
+ &compress, tx);
+ error = error ? error : zap_update(os, ZVOL_ZAP_OBJ,
+ zfs_prop_to_name(ZFS_PROP_CHECKSUM), 8, 1, &checksum, tx);
+ error = error ? error : zap_update(os, ZVOL_ZAP_OBJ,
+ zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1,
+ &refresrv, tx);
+ error = error ? error : zap_update(os, ZVOL_ZAP_OBJ,
+ zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), 8, 1,
+ &vbs, tx);
+ error = error ? error : dmu_object_set_blocksize(
+ os, ZVOL_OBJ, SPA_MAXBLOCKSIZE, 0, tx);
+ if (version >= SPA_VERSION_DEDUP) {
+ error = error ? error : zap_update(os, ZVOL_ZAP_OBJ,
+ zfs_prop_to_name(ZFS_PROP_DEDUP), 8, 1,
+ &dedup, tx);
+ }
+ if (error == 0)
+ zv->zv_volblocksize = SPA_MAXBLOCKSIZE;
+ }
+ dmu_tx_commit(tx);
+
+ /*
+ * We only need update the zvol's property if we are initializing
+ * the dump area for the first time.
+ */
+ if (!resize) {
+ VERIFY(nvlist_alloc(&nv, NV_UNIQUE_NAME, KM_SLEEP) == 0);
+ VERIFY(nvlist_add_uint64(nv,
+ zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 0) == 0);
+ VERIFY(nvlist_add_uint64(nv,
+ zfs_prop_to_name(ZFS_PROP_COMPRESSION),
+ ZIO_COMPRESS_OFF) == 0);
+ VERIFY(nvlist_add_uint64(nv,
+ zfs_prop_to_name(ZFS_PROP_CHECKSUM),
+ ZIO_CHECKSUM_OFF) == 0);
+ if (version >= SPA_VERSION_DEDUP) {
+ VERIFY(nvlist_add_uint64(nv,
+ zfs_prop_to_name(ZFS_PROP_DEDUP),
+ ZIO_CHECKSUM_OFF) == 0);
+ }
+
+ error = zfs_set_prop_nvlist(zv->zv_name, ZPROP_SRC_LOCAL,
+ nv, NULL);
+ nvlist_free(nv);
+
+ if (error)
+ return (error);
+ }
+
+ /* Allocate the space for the dump */
+ error = zvol_prealloc(zv);
+ return (error);
+}
+
+static int
+zvol_dumpify(zvol_state_t *zv)
+{
+ int error = 0;
+ uint64_t dumpsize = 0;
+ dmu_tx_t *tx;
+ objset_t *os = zv->zv_objset;
+
+ if (zv->zv_flags & ZVOL_RDONLY)
+ return (EROFS);
+
+ if (zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE,
+ 8, 1, &dumpsize) != 0 || dumpsize != zv->zv_volsize) {
+ boolean_t resize = (dumpsize > 0) ? B_TRUE : B_FALSE;
+
+ if ((error = zvol_dump_init(zv, resize)) != 0) {
+ (void) zvol_dump_fini(zv);
+ return (error);
+ }
+ }
+
+ /*
+ * Build up our lba mapping.
+ */
+ error = zvol_get_lbas(zv);
+ if (error) {
+ (void) zvol_dump_fini(zv);
+ return (error);
+ }
+
+ tx = dmu_tx_create(os);
+ dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL);
+ error = dmu_tx_assign(tx, TXG_WAIT);
+ if (error) {
+ dmu_tx_abort(tx);
+ (void) zvol_dump_fini(zv);
+ return (error);
+ }
+
+ zv->zv_flags |= ZVOL_DUMPIFIED;
+ error = zap_update(os, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE, 8, 1,
+ &zv->zv_volsize, tx);
+ dmu_tx_commit(tx);
+
+ if (error) {
+ (void) zvol_dump_fini(zv);
+ return (error);
+ }
+
+ txg_wait_synced(dmu_objset_pool(os), 0);
+ return (0);
+}
+
+static int
+zvol_dump_fini(zvol_state_t *zv)
+{
+ dmu_tx_t *tx;
+ objset_t *os = zv->zv_objset;
+ nvlist_t *nv;
+ int error = 0;
+ uint64_t checksum, compress, refresrv, vbs, dedup;
+ uint64_t version = spa_version(dmu_objset_spa(zv->zv_objset));
+
+ /*
+ * Attempt to restore the zvol back to its pre-dumpified state.
+ * This is a best-effort attempt as it's possible that not all
+ * of these properties were initialized during the dumpify process
+ * (i.e. error during zvol_dump_init).
+ */
+
+ tx = dmu_tx_create(os);
+ dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL);
+ error = dmu_tx_assign(tx, TXG_WAIT);
+ if (error) {
+ dmu_tx_abort(tx);
+ return (error);
+ }
+ (void) zap_remove(os, ZVOL_ZAP_OBJ, ZVOL_DUMPSIZE, tx);
+ dmu_tx_commit(tx);
+
+ (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ,
+ zfs_prop_to_name(ZFS_PROP_CHECKSUM), 8, 1, &checksum);
+ (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ,
+ zfs_prop_to_name(ZFS_PROP_COMPRESSION), 8, 1, &compress);
+ (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ,
+ zfs_prop_to_name(ZFS_PROP_REFRESERVATION), 8, 1, &refresrv);
+ (void) zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ,
+ zfs_prop_to_name(ZFS_PROP_VOLBLOCKSIZE), 8, 1, &vbs);
+
+ VERIFY(nvlist_alloc(&nv, NV_UNIQUE_NAME, KM_SLEEP) == 0);
+ (void) nvlist_add_uint64(nv,
+ zfs_prop_to_name(ZFS_PROP_CHECKSUM), checksum);
+ (void) nvlist_add_uint64(nv,
+ zfs_prop_to_name(ZFS_PROP_COMPRESSION), compress);
+ (void) nvlist_add_uint64(nv,
+ zfs_prop_to_name(ZFS_PROP_REFRESERVATION), refresrv);
+ if (version >= SPA_VERSION_DEDUP &&
+ zap_lookup(zv->zv_objset, ZVOL_ZAP_OBJ,
+ zfs_prop_to_name(ZFS_PROP_DEDUP), 8, 1, &dedup) == 0) {
+ (void) nvlist_add_uint64(nv,
+ zfs_prop_to_name(ZFS_PROP_DEDUP), dedup);
+ }
+ (void) zfs_set_prop_nvlist(zv->zv_name, ZPROP_SRC_LOCAL,
+ nv, NULL);
+ nvlist_free(nv);
+
+ zvol_free_extents(zv);
+ zv->zv_flags &= ~ZVOL_DUMPIFIED;
+ (void) dmu_free_long_range(os, ZVOL_OBJ, 0, DMU_OBJECT_END);
+ /* wait for dmu_free_long_range to actually free the blocks */
+ txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0);
+ tx = dmu_tx_create(os);
+ dmu_tx_hold_bonus(tx, ZVOL_OBJ);
+ error = dmu_tx_assign(tx, TXG_WAIT);
+ if (error) {
+ dmu_tx_abort(tx);
+ return (error);
+ }
+ if (dmu_object_set_blocksize(os, ZVOL_OBJ, vbs, 0, tx) == 0)
+ zv->zv_volblocksize = vbs;
+ dmu_tx_commit(tx);
+
+ return (0);
+}