Add zfs_prepare_disk script for disk firmware install

Have libzfs call a special `zfs_prepare_disk` script before a disk is
included into the pool.  The user can edit this script to add things
like a disk firmware update or a disk health check.  Use of the script
is totally optional. See the zfs_prepare_disk manpage for full details.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Tony Hutter <hutter2@llnl.gov>
Closes #15243

cmd/zpool/zpool_iter.c

@@ -443,37 +443,22 @@ vdev_run_cmd(vdev_cmd_data_t *data, char *cmd)
 {
 	int rc;
 	char *argv[2] = {cmd};
-	char *env[5] = {(char *)"PATH=/bin:/sbin:/usr/bin:/usr/sbin"};
+	char **env;
 	char **lines = NULL;
 	int lines_cnt = 0;
 	int i;
 
-	/* Setup our custom environment variables */
-	rc = asprintf(&env[1], "VDEV_PATH=%s",
-	    data->path ? data->path : "");
-	if (rc == -1) {
-		env[1] = NULL;
+	env = zpool_vdev_script_alloc_env(data->pool, data->path, data->upath,
+	    data->vdev_enc_sysfs_path, NULL, NULL);
+	if (env == NULL)
 		goto out;
-	}
-
-	rc = asprintf(&env[2], "VDEV_UPATH=%s",
-	    data->upath ? data->upath : "");
-	if (rc == -1) {
-		env[2] = NULL;
-		goto out;
-	}
-
-	rc = asprintf(&env[3], "VDEV_ENC_SYSFS_PATH=%s",
-	    data->vdev_enc_sysfs_path ?
-	    data->vdev_enc_sysfs_path : "");
-	if (rc == -1) {
-		env[3] = NULL;
-		goto out;
-	}
 
 	/* Run the command */
 	rc = libzfs_run_process_get_stdout_nopath(cmd, argv, env, &lines,
 	    &lines_cnt);
+
+	zpool_vdev_script_free_env(env);
+
 	if (rc != 0)
 		goto out;
 
@@ -485,10 +470,6 @@ vdev_run_cmd(vdev_cmd_data_t *data, char *cmd)
 out:
 	if (lines != NULL)
 		libzfs_free_str_array(lines, lines_cnt);
-
-	/* Start with i = 1 since env[0] was statically allocated */
-	for (i = 1; i < ARRAY_SIZE(env); i++)
-		free(env[i]);
 }
 
 /*

cmd/zpool/zpool_util.h

@@ -126,6 +126,10 @@ vdev_cmd_data_list_t *all_pools_for_each_vdev_run(int argc, char **argv,
 
 void free_vdev_cmd_data_list(vdev_cmd_data_list_t *vcdl);
 
+void free_vdev_cmd_data(vdev_cmd_data_t *data);
+
+int vdev_run_cmd_simple(char *path, char *cmd);
+
 int check_device(const char *path, boolean_t force,
     boolean_t isspare, boolean_t iswholedisk);
 boolean_t check_sector_size_database(char *path, int *sector_size);

cmd/zpool/zpool_vdev.c

@@ -936,6 +936,15 @@ zero_label(const char *path)
 	return (0);
 }
 
+static void
+lines_to_stderr(char *lines[], int lines_cnt)
+{
+	int i;
+	for (i = 0; i < lines_cnt; i++) {
+		fprintf(stderr, "%s\n", lines[i]);
+	}
+}
+
 /*
  * Go through and find any whole disks in the vdev specification, labelling them
  * as appropriate.  When constructing the vdev spec, we were unable to open this
@@ -947,7 +956,7 @@ zero_label(const char *path)
  * need to get the devid after we label the disk.
  */
 static int
-make_disks(zpool_handle_t *zhp, nvlist_t *nv)
+make_disks(zpool_handle_t *zhp, nvlist_t *nv, boolean_t replacing)
 {
 	nvlist_t **child;
 	uint_t c, children;
@@ -1032,6 +1041,8 @@ make_disks(zpool_handle_t *zhp, nvlist_t *nv)
 		 */
 		if (!is_exclusive && !is_spare(NULL, udevpath)) {
 			char *devnode = strrchr(devpath, '/') + 1;
+			char **lines = NULL;
+			int lines_cnt = 0;
 
 			ret = strncmp(udevpath, UDISK_ROOT, strlen(UDISK_ROOT));
 			if (ret == 0) {
@@ -1043,9 +1054,27 @@ make_disks(zpool_handle_t *zhp, nvlist_t *nv)
 			/*
 			 * When labeling a pool the raw device node name
 			 * is provided as it appears under /dev/.
+			 *
+			 * Note that 'zhp' will be NULL when we're creating a
+			 * pool.
 			 */
-			if (zpool_label_disk(g_zfs, zhp, devnode) == -1)
+			if (zpool_prepare_and_label_disk(g_zfs, zhp, devnode,
+			    nv, zhp == NULL ? "create" :
+			    replacing ? "replace" : "add", &lines,
+			    &lines_cnt) != 0) {
+				(void) fprintf(stderr,
+				    gettext(
+				    "Error preparing/labeling disk.\n"));
+				if (lines_cnt > 0) {
+					(void) fprintf(stderr,
+					gettext("zfs_prepare_disk output:\n"));
+					lines_to_stderr(lines, lines_cnt);
+				}
+
+				libzfs_free_str_array(lines, lines_cnt);
 				return (-1);
+			}
+			libzfs_free_str_array(lines, lines_cnt);
 
 			/*
 			 * Wait for udev to signal the device is available
@@ -1082,19 +1111,19 @@ make_disks(zpool_handle_t *zhp, nvlist_t *nv)
 	}
 
 	for (c = 0; c < children; c++)
-		if ((ret = make_disks(zhp, child[c])) != 0)
+		if ((ret = make_disks(zhp, child[c], replacing)) != 0)
 			return (ret);
 
 	if (nvlist_lookup_nvlist_array(nv, ZPOOL_CONFIG_SPARES,
 	    &child, &children) == 0)
 		for (c = 0; c < children; c++)
-			if ((ret = make_disks(zhp, child[c])) != 0)
+			if ((ret = make_disks(zhp, child[c], replacing)) != 0)
 				return (ret);
 
 	if (nvlist_lookup_nvlist_array(nv, ZPOOL_CONFIG_L2CACHE,
 	    &child, &children) == 0)
 		for (c = 0; c < children; c++)
-			if ((ret = make_disks(zhp, child[c])) != 0)
+			if ((ret = make_disks(zhp, child[c], replacing)) != 0)
 				return (ret);
 
 	return (0);
@@ -1752,7 +1781,7 @@ split_mirror_vdev(zpool_handle_t *zhp, char *newname, nvlist_t *props,
 			return (NULL);
 		}
 
-		if (!flags.dryrun && make_disks(zhp, newroot) != 0) {
+		if (!flags.dryrun && make_disks(zhp, newroot, B_FALSE) != 0) {
 			nvlist_free(newroot);
 			return (NULL);
 		}
@@ -1873,7 +1902,7 @@ make_root_vdev(zpool_handle_t *zhp, nvlist_t *props, int force, int check_rep,
 	/*
 	 * Run through the vdev specification and label any whole disks found.
 	 */
-	if (!dryrun && make_disks(zhp, newroot) != 0) {
+	if (!dryrun && make_disks(zhp, newroot, replacing) != 0) {
 		nvlist_free(newroot);
 		return (NULL);
 	}