1 files changed, 361 insertions, 0 deletions
diff --git a/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/spa_config.c b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/spa_config.c
new file mode 100644
index 0000000..b5d8c38
--- /dev/null
+++ b/sys/cddl/contrib/opensolaris/uts/common/fs/zfs/spa_config.c
@@ -0,0 +1,361 @@
+/*
+ * 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 2007 Sun Microsystems, Inc.  All rights reserved.
+ * Use is subject to license terms.
+ */
+
+#pragma ident	"%Z%%M%	%I%	%E% SMI"
+
+#include <sys/zfs_context.h>
+#include <sys/spa.h>
+#include <sys/spa_impl.h>
+#include <sys/nvpair.h>
+#include <sys/uio.h>
+#include <sys/fs/zfs.h>
+#include <sys/vdev_impl.h>
+#include <sys/zfs_ioctl.h>
+#ifdef _KERNEL
+#include <sys/kobj.h>
+#endif
+
+/*
+ * Pool configuration repository.
+ *
+ * The configuration for all pools, in addition to being stored on disk, is
+ * stored in /etc/zfs/zpool.cache as a packed nvlist.  The kernel maintains
+ * this list as pools are created, destroyed, or modified.
+ *
+ * We have a single nvlist which holds all the configuration information.  When
+ * the module loads, we read this information from the cache and populate the
+ * SPA namespace.  This namespace is maintained independently in spa.c.
+ * Whenever the namespace is modified, or the configuration of a pool is
+ * changed, we call spa_config_sync(), which walks through all the active pools
+ * and writes the configuration to disk.
+ */
+
+static uint64_t spa_config_generation = 1;
+
+/*
+ * This can be overridden in userland to preserve an alternate namespace for
+ * userland pools when doing testing.
+ */
+const char *spa_config_dir = ZPOOL_CACHE_DIR;
+
+/*
+ * Called when the module is first loaded, this routine loads the configuration
+ * file into the SPA namespace.  It does not actually open or load the pools; it
+ * only populates the namespace.
+ */
+void
+spa_config_load(void)
+{
+	void *buf = NULL;
+	nvlist_t *nvlist, *child;
+	nvpair_t *nvpair;
+	spa_t *spa;
+	char pathname[128];
+	struct _buf *file;
+	uint64_t fsize;
+
+	root_mount_wait();
+
+	/*
+	 * Open the configuration file.
+	 */
+	(void) snprintf(pathname, sizeof (pathname), "%s/%s",
+	    spa_config_dir, ZPOOL_CACHE_FILE);
+
+	file = kobj_open_file(pathname);
+	if (file == (struct _buf *)-1)
+		return;
+
+	if (kobj_get_filesize(file, &fsize) != 0)
+		goto out;
+
+	buf = kmem_alloc(fsize, KM_SLEEP);
+
+	/*
+	 * Read the nvlist from the file.
+	 */
+	if (kobj_read_file(file, buf, fsize, 0) < 0)
+		goto out;
+
+	/*
+	 * Unpack the nvlist.
+	 */
+	if (nvlist_unpack(buf, fsize, &nvlist, KM_SLEEP) != 0)
+		goto out;
+
+	/*
+	 * Iterate over all elements in the nvlist, creating a new spa_t for
+	 * each one with the specified configuration.
+	 */
+	mutex_enter(&spa_namespace_lock);
+	nvpair = NULL;
+	while ((nvpair = nvlist_next_nvpair(nvlist, nvpair)) != NULL) {
+
+		if (nvpair_type(nvpair) != DATA_TYPE_NVLIST)
+			continue;
+
+		VERIFY(nvpair_value_nvlist(nvpair, &child) == 0);
+
+		if (spa_lookup(nvpair_name(nvpair)) != NULL)
+			continue;
+		spa = spa_add(nvpair_name(nvpair), NULL);
+
+		/*
+		 * We blindly duplicate the configuration here.  If it's
+		 * invalid, we will catch it when the pool is first opened.
+		 */
+		VERIFY(nvlist_dup(child, &spa->spa_config, 0) == 0);
+	}
+	mutex_exit(&spa_namespace_lock);
+
+	nvlist_free(nvlist);
+
+out:
+	if (buf != NULL)
+		kmem_free(buf, fsize);
+
+	kobj_close_file(file);
+}
+
+/*
+ * Synchronize all pools to disk.  This must be called with the namespace lock
+ * held.
+ */
+void
+spa_config_sync(void)
+{
+	spa_t *spa = NULL;
+	nvlist_t *config;
+	size_t buflen;
+	char *buf;
+	vnode_t *vp;
+	int oflags = FWRITE | FTRUNC | FCREAT | FOFFMAX;
+	char pathname[128];
+	char pathname2[128];
+
+	ASSERT(MUTEX_HELD(&spa_namespace_lock));
+
+	VERIFY(nvlist_alloc(&config, NV_UNIQUE_NAME, KM_SLEEP) == 0);
+
+	/*
+	 * Add all known pools to the configuration list, ignoring those with
+	 * alternate root paths.
+	 */
+	spa = NULL;
+	while ((spa = spa_next(spa)) != NULL) {
+		mutex_enter(&spa->spa_config_cache_lock);
+		if (spa->spa_config && spa->spa_name && spa->spa_root == NULL)
+			VERIFY(nvlist_add_nvlist(config, spa->spa_name,
+			    spa->spa_config) == 0);
+		mutex_exit(&spa->spa_config_cache_lock);
+	}
+
+	/*
+	 * Pack the configuration into a buffer.
+	 */
+	VERIFY(nvlist_size(config, &buflen, NV_ENCODE_XDR) == 0);
+
+	buf = kmem_alloc(buflen, KM_SLEEP);
+
+	VERIFY(nvlist_pack(config, &buf, &buflen, NV_ENCODE_XDR,
+	    KM_SLEEP) == 0);
+
+	/*
+	 * Write the configuration to disk.  We need to do the traditional
+	 * 'write to temporary file, sync, move over original' to make sure we
+	 * always have a consistent view of the data.
+	 */
+	(void) snprintf(pathname, sizeof (pathname), "%s/%s", spa_config_dir,
+	    ZPOOL_CACHE_TMP);
+
+	if (vn_open(pathname, UIO_SYSSPACE, oflags, 0644, &vp, CRCREAT, 0) != 0)
+		goto out;
+
+	if (vn_rdwr(UIO_WRITE, vp, buf, buflen, 0, UIO_SYSSPACE,
+	    0, RLIM64_INFINITY, kcred, NULL) == 0 &&
+	    VOP_FSYNC(vp, FSYNC, kcred) == 0) {
+		(void) snprintf(pathname2, sizeof (pathname2), "%s/%s",
+		    spa_config_dir, ZPOOL_CACHE_FILE);
+		(void) vn_rename(pathname, pathname2, UIO_SYSSPACE);
+	}
+
+	(void) VOP_CLOSE(vp, oflags, 1, 0, kcred);
+	VN_RELE(vp);
+
+out:
+	(void) vn_remove(pathname, UIO_SYSSPACE, RMFILE);
+	spa_config_generation++;
+
+	kmem_free(buf, buflen);
+	nvlist_free(config);
+}
+
+/*
+ * Sigh.  Inside a local zone, we don't have access to /etc/zfs/zpool.cache,
+ * and we don't want to allow the local zone to see all the pools anyway.
+ * So we have to invent the ZFS_IOC_CONFIG ioctl to grab the configuration
+ * information for all pool visible within the zone.
+ */
+nvlist_t *
+spa_all_configs(uint64_t *generation)
+{
+	nvlist_t *pools;
+	spa_t *spa;
+
+	if (*generation == spa_config_generation)
+		return (NULL);
+
+	VERIFY(nvlist_alloc(&pools, NV_UNIQUE_NAME, KM_SLEEP) == 0);
+
+	spa = NULL;
+	mutex_enter(&spa_namespace_lock);
+	while ((spa = spa_next(spa)) != NULL) {
+		if (INGLOBALZONE(curproc) ||
+		    zone_dataset_visible(spa_name(spa), NULL)) {
+			mutex_enter(&spa->spa_config_cache_lock);
+			VERIFY(nvlist_add_nvlist(pools, spa_name(spa),
+			    spa->spa_config) == 0);
+			mutex_exit(&spa->spa_config_cache_lock);
+		}
+	}
+	mutex_exit(&spa_namespace_lock);
+
+	*generation = spa_config_generation;
+
+	return (pools);
+}
+
+void
+spa_config_set(spa_t *spa, nvlist_t *config)
+{
+	mutex_enter(&spa->spa_config_cache_lock);
+	if (spa->spa_config != NULL)
+		nvlist_free(spa->spa_config);
+	spa->spa_config = config;
+	mutex_exit(&spa->spa_config_cache_lock);
+}
+
+/*
+ * Generate the pool's configuration based on the current in-core state.
+ * We infer whether to generate a complete config or just one top-level config
+ * based on whether vd is the root vdev.
+ */
+nvlist_t *
+spa_config_generate(spa_t *spa, vdev_t *vd, uint64_t txg, int getstats)
+{
+	nvlist_t *config, *nvroot;
+	vdev_t *rvd = spa->spa_root_vdev;
+
+	ASSERT(spa_config_held(spa, RW_READER));
+
+	if (vd == NULL)
+		vd = rvd;
+
+	/*
+	 * If txg is -1, report the current value of spa->spa_config_txg.
+	 */
+	if (txg == -1ULL)
+		txg = spa->spa_config_txg;
+
+	VERIFY(nvlist_alloc(&config, NV_UNIQUE_NAME, KM_SLEEP) == 0);
+
+	VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_VERSION,
+	    spa_version(spa)) == 0);
+	VERIFY(nvlist_add_string(config, ZPOOL_CONFIG_POOL_NAME,
+	    spa_name(spa)) == 0);
+	VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_POOL_STATE,
+	    spa_state(spa)) == 0);
+	VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_POOL_TXG,
+	    txg) == 0);
+	VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_POOL_GUID,
+	    spa_guid(spa)) == 0);
+
+	if (vd != rvd) {
+		VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_TOP_GUID,
+		    vd->vdev_top->vdev_guid) == 0);
+		VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_GUID,
+		    vd->vdev_guid) == 0);
+		if (vd->vdev_isspare)
+			VERIFY(nvlist_add_uint64(config, ZPOOL_CONFIG_IS_SPARE,
+			    1ULL) == 0);
+		vd = vd->vdev_top;		/* label contains top config */
+	}
+
+	nvroot = vdev_config_generate(spa, vd, getstats, B_FALSE);
+	VERIFY(nvlist_add_nvlist(config, ZPOOL_CONFIG_VDEV_TREE, nvroot) == 0);
+	nvlist_free(nvroot);
+
+	return (config);
+}
+
+/*
+ * Update all disk labels, generate a fresh config based on the current
+ * in-core state, and sync the global config cache.
+ */
+void
+spa_config_update(spa_t *spa, int what)
+{
+	vdev_t *rvd = spa->spa_root_vdev;
+	uint64_t txg;
+	int c;
+
+	ASSERT(MUTEX_HELD(&spa_namespace_lock));
+
+	spa_config_enter(spa, RW_WRITER, FTAG);
+	txg = spa_last_synced_txg(spa) + 1;
+	if (what == SPA_CONFIG_UPDATE_POOL) {
+		vdev_config_dirty(rvd);
+	} else {
+		/*
+		 * If we have top-level vdevs that were added but have
+		 * not yet been prepared for allocation, do that now.
+		 * (It's safe now because the config cache is up to date,
+		 * so it will be able to translate the new DVAs.)
+		 * See comments in spa_vdev_add() for full details.
+		 */
+		for (c = 0; c < rvd->vdev_children; c++) {
+			vdev_t *tvd = rvd->vdev_child[c];
+			if (tvd->vdev_ms_array == 0) {
+				vdev_init(tvd, txg);
+				vdev_config_dirty(tvd);
+			}
+		}
+	}
+	spa_config_exit(spa, FTAG);
+
+	/*
+	 * Wait for the mosconfig to be regenerated and synced.
+	 */
+	txg_wait_synced(spa->spa_dsl_pool, txg);
+
+	/*
+	 * Update the global config cache to reflect the new mosconfig.
+	 */
+	spa_config_sync();
+
+	if (what == SPA_CONFIG_UPDATE_POOL)
+		spa_config_update(spa, SPA_CONFIG_UPDATE_VDEVS);
+}