OpenZFS 9166 - zfs storage pool checkpoint

[mirror_zfs.git] / cmd / zpool / zpool_iter.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*
 * Copyright 2016 Igor Kozhukhov <ikozhukhov@gmail.com>.
 */

#include <libintl.h>
#include <libuutil.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <strings.h>
#include <thread_pool.h>

#include <libzfs.h>
#include <sys/zfs_context.h>
#include <sys/wait.h>

#include "zpool_util.h"

/*
 * Private interface for iterating over pools specified on the command line.
 * Most consumers will call for_each_pool, but in order to support iostat, we
 * allow fined grained control through the zpool_list_t interface.
 */

typedef struct zpool_node {
        zpool_handle_t  *zn_handle;
        uu_avl_node_t   zn_avlnode;
        int             zn_mark;
} zpool_node_t;

struct zpool_list {
        boolean_t       zl_findall;
        uu_avl_t        *zl_avl;
        uu_avl_pool_t   *zl_pool;
        zprop_list_t    **zl_proplist;
};

/* ARGSUSED */
static int
zpool_compare(const void *larg, const void *rarg, void *unused)
{
        zpool_handle_t *l = ((zpool_node_t *)larg)->zn_handle;
        zpool_handle_t *r = ((zpool_node_t *)rarg)->zn_handle;
        const char *lname = zpool_get_name(l);
        const char *rname = zpool_get_name(r);

        return (strcmp(lname, rname));
}

/*
 * Callback function for pool_list_get().  Adds the given pool to the AVL tree
 * of known pools.
 */
static int
add_pool(zpool_handle_t *zhp, void *data)
{
        zpool_list_t *zlp = data;
        zpool_node_t *node = safe_malloc(sizeof (zpool_node_t));
        uu_avl_index_t idx;

        node->zn_handle = zhp;
        uu_avl_node_init(node, &node->zn_avlnode, zlp->zl_pool);
        if (uu_avl_find(zlp->zl_avl, node, NULL, &idx) == NULL) {
                if (zlp->zl_proplist &&
                    zpool_expand_proplist(zhp, zlp->zl_proplist) != 0) {
                        zpool_close(zhp);
                        free(node);
                        return (-1);
                }
                uu_avl_insert(zlp->zl_avl, node, idx);
        } else {
                zpool_close(zhp);
                free(node);
                return (-1);
        }

        return (0);
}

/*
 * Create a list of pools based on the given arguments.  If we're given no
 * arguments, then iterate over all pools in the system and add them to the AVL
 * tree.  Otherwise, add only those pool explicitly specified on the command
 * line.
 */
zpool_list_t *
pool_list_get(int argc, char **argv, zprop_list_t **proplist, int *err)
{
        zpool_list_t *zlp;

        zlp = safe_malloc(sizeof (zpool_list_t));

        zlp->zl_pool = uu_avl_pool_create("zfs_pool", sizeof (zpool_node_t),
            offsetof(zpool_node_t, zn_avlnode), zpool_compare, UU_DEFAULT);

        if (zlp->zl_pool == NULL)
                zpool_no_memory();

        if ((zlp->zl_avl = uu_avl_create(zlp->zl_pool, NULL,
            UU_DEFAULT)) == NULL)
                zpool_no_memory();

        zlp->zl_proplist = proplist;

        if (argc == 0) {
                (void) zpool_iter(g_zfs, add_pool, zlp);
                zlp->zl_findall = B_TRUE;
        } else {
                int i;

                for (i = 0; i < argc; i++) {
                        zpool_handle_t *zhp;

                        if ((zhp = zpool_open_canfail(g_zfs, argv[i])) !=
                            NULL) {
                                if (add_pool(zhp, zlp) != 0)
                                        *err = B_TRUE;
                        } else {
                                *err = B_TRUE;
                        }
                }
        }

        return (zlp);
}

/*
 * Search for any new pools, adding them to the list.  We only add pools when no
 * options were given on the command line.  Otherwise, we keep the list fixed as
 * those that were explicitly specified.
 */
void
pool_list_update(zpool_list_t *zlp)
{
        if (zlp->zl_findall)
                (void) zpool_iter(g_zfs, add_pool, zlp);
}

/*
 * Iterate over all pools in the list, executing the callback for each
 */
int
pool_list_iter(zpool_list_t *zlp, int unavail, zpool_iter_f func,
    void *data)
{
        zpool_node_t *node, *next_node;
        int ret = 0;

        for (node = uu_avl_first(zlp->zl_avl); node != NULL; node = next_node) {
                next_node = uu_avl_next(zlp->zl_avl, node);
                if (zpool_get_state(node->zn_handle) != POOL_STATE_UNAVAIL ||
                    unavail)
                        ret |= func(node->zn_handle, data);
        }

        return (ret);
}

/*
 * Remove the given pool from the list.  When running iostat, we want to remove
 * those pools that no longer exist.
 */
void
pool_list_remove(zpool_list_t *zlp, zpool_handle_t *zhp)
{
        zpool_node_t search, *node;

        search.zn_handle = zhp;
        if ((node = uu_avl_find(zlp->zl_avl, &search, NULL, NULL)) != NULL) {
                uu_avl_remove(zlp->zl_avl, node);
                zpool_close(node->zn_handle);
                free(node);
        }
}

/*
 * Free all the handles associated with this list.
 */
void
pool_list_free(zpool_list_t *zlp)
{
        uu_avl_walk_t *walk;
        zpool_node_t *node;

        if ((walk = uu_avl_walk_start(zlp->zl_avl, UU_WALK_ROBUST)) == NULL) {
                (void) fprintf(stderr,
                    gettext("internal error: out of memory"));
                exit(1);
        }

        while ((node = uu_avl_walk_next(walk)) != NULL) {
                uu_avl_remove(zlp->zl_avl, node);
                zpool_close(node->zn_handle);
                free(node);
        }

        uu_avl_walk_end(walk);
        uu_avl_destroy(zlp->zl_avl);
        uu_avl_pool_destroy(zlp->zl_pool);

        free(zlp);
}

/*
 * Returns the number of elements in the pool list.
 */
int
pool_list_count(zpool_list_t *zlp)
{
        return (uu_avl_numnodes(zlp->zl_avl));
}

/*
 * High level function which iterates over all pools given on the command line,
 * using the pool_list_* interfaces.
 */
int
for_each_pool(int argc, char **argv, boolean_t unavail,
    zprop_list_t **proplist, zpool_iter_f func, void *data)
{
        zpool_list_t *list;
        int ret = 0;

        if ((list = pool_list_get(argc, argv, proplist, &ret)) == NULL)
                return (1);

        if (pool_list_iter(list, unavail, func, data) != 0)
                ret = 1;

        pool_list_free(list);

        return (ret);
}

static int
for_each_vdev_cb(zpool_handle_t *zhp, nvlist_t *nv, pool_vdev_iter_f func,
    void *data)
{
        nvlist_t **child;
        uint_t c, children;
        int ret = 0;
        int i;
        char *type;

        const char *list[] = {
            ZPOOL_CONFIG_SPARES,
            ZPOOL_CONFIG_L2CACHE,
            ZPOOL_CONFIG_CHILDREN
        };

        for (i = 0; i < ARRAY_SIZE(list); i++) {
                if (nvlist_lookup_nvlist_array(nv, list[i], &child,
                    &children) == 0) {
                        for (c = 0; c < children; c++) {
                                uint64_t ishole = 0;

                                (void) nvlist_lookup_uint64(child[c],
                                    ZPOOL_CONFIG_IS_HOLE, &ishole);

                                if (ishole)
                                        continue;

                                ret |= for_each_vdev_cb(zhp, child[c], func,
                                    data);
                        }
                }
        }

        if (nvlist_lookup_string(nv, ZPOOL_CONFIG_TYPE, &type) != 0)
                return (ret);

        /* Don't run our function on root vdevs */
        if (strcmp(type, VDEV_TYPE_ROOT) != 0) {
                ret |= func(zhp, nv, data);
        }

        return (ret);
}

/*
 * This is the equivalent of for_each_pool() for vdevs.  It iterates thorough
 * all vdevs in the pool, ignoring root vdevs and holes, calling func() on
 * each one.
 *
 * @zhp:        Zpool handle
 * @func:       Function to call on each vdev
 * @data:       Custom data to pass to the function
 */
int
for_each_vdev(zpool_handle_t *zhp, pool_vdev_iter_f func, void *data)
{
        nvlist_t *config, *nvroot = NULL;

        if ((config = zpool_get_config(zhp, NULL)) != NULL) {
                verify(nvlist_lookup_nvlist(config, ZPOOL_CONFIG_VDEV_TREE,
                    &nvroot) == 0);
        }
        return (for_each_vdev_cb(zhp, nvroot, func, data));
}

/*
 * Process the vcdl->vdev_cmd_data[] array to figure out all the unique column
 * names and their widths.  When this function is done, vcdl->uniq_cols,
 * vcdl->uniq_cols_cnt, and vcdl->uniq_cols_width will be filled in.
 */
static void
process_unique_cmd_columns(vdev_cmd_data_list_t *vcdl)
{
        char **uniq_cols = NULL, **tmp = NULL;
        int *uniq_cols_width;
        vdev_cmd_data_t *data;
        int cnt = 0;
        int k;

        /* For each vdev */
        for (int i = 0; i < vcdl->count; i++) {
                data = &vcdl->data[i];
                /* For each column the vdev reported */
                for (int j = 0; j < data->cols_cnt; j++) {
                        /* Is this column in our list of unique column names? */
                        for (k = 0; k < cnt; k++) {
                                if (strcmp(data->cols[j], uniq_cols[k]) == 0)
                                        break; /* yes it is */
                        }
                        if (k == cnt) {
                                /* No entry for column, add to list */
                                tmp = realloc(uniq_cols, sizeof (*uniq_cols) *
                                    (cnt + 1));
                                if (tmp == NULL)
                                        break; /* Nothing we can do... */
                                uniq_cols = tmp;
                                uniq_cols[cnt] = data->cols[j];
                                cnt++;
                        }
                }
        }

        /*
         * We now have a list of all the unique column names.  Figure out the
         * max width of each column by looking at the column name and all its
         * values.
         */
        uniq_cols_width = safe_malloc(sizeof (*uniq_cols_width) * cnt);
        for (int i = 0; i < cnt; i++) {
                /* Start off with the column title's width */
                uniq_cols_width[i] = strlen(uniq_cols[i]);
                /* For each vdev */
                for (int j = 0; j < vcdl->count; j++) {
                        /* For each of the vdev's values in a column */
                        data = &vcdl->data[j];
                        for (k = 0; k < data->cols_cnt; k++) {
                                /* Does this vdev have a value for this col? */
                                if (strcmp(data->cols[k], uniq_cols[i]) == 0) {
                                        /* Is the value width larger? */
                                        uniq_cols_width[i] =
                                            MAX(uniq_cols_width[i],
                                            strlen(data->lines[k]));
                                }
                        }
                }
        }

        vcdl->uniq_cols = uniq_cols;
        vcdl->uniq_cols_cnt = cnt;
        vcdl->uniq_cols_width = uniq_cols_width;
}


/*
 * Process a line of command output
 *
 * When running 'zpool iostat|status -c' the lines of output can either be
 * in the form of:
 *
 *      column_name=value
 *
 * Or just:
 *
 *      value
 *
 * Process the column_name (if any) and value.
 *
 * Returns 0 if line was processed, and there are more lines can still be
 * processed.
 *
 * Returns 1 if this was the last line to process, or error.
 */
static int
vdev_process_cmd_output(vdev_cmd_data_t *data, char *line)
{
        char *col = NULL;
        char *val = line;
        char *equals;
        char **tmp;

        if (line == NULL)
                return (1);

        equals = strchr(line, '=');
        if (equals != NULL) {
                /*
                 * We have a 'column=value' type line.  Split it into the
                 * column and value strings by turning the '=' into a '\0'.
                 */
                *equals = '\0';
                col = line;
                val = equals + 1;
        } else {
                val = line;
        }

        /* Do we already have a column by this name?  If so, skip it. */
        if (col != NULL) {
                for (int i = 0; i < data->cols_cnt; i++) {
                        if (strcmp(col, data->cols[i]) == 0)
                                return (0); /* Duplicate, skip */
                }
        }

        if (val != NULL) {
                tmp = realloc(data->lines,
                    (data->lines_cnt + 1) * sizeof (*data->lines));
                if (tmp == NULL)
                        return (1);

                data->lines = tmp;
                data->lines[data->lines_cnt] = strdup(val);
                data->lines_cnt++;
        }

        if (col != NULL) {
                tmp = realloc(data->cols,
                    (data->cols_cnt + 1) * sizeof (*data->cols));
                if (tmp == NULL)
                        return (1);

                data->cols = tmp;
                data->cols[data->cols_cnt] = strdup(col);
                data->cols_cnt++;
        }

        if (val != NULL && col == NULL)
                return (1);

        return (0);
}

/*
 * Run the cmd and store results in *data.
 */
static void
vdev_run_cmd(vdev_cmd_data_t *data, char *cmd)
{
        int rc;
        char *argv[2] = {cmd, 0};
        char *env[5] = {"PATH=/bin:/sbin:/usr/bin:/usr/sbin", NULL, NULL, NULL,
            NULL};
        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)
                goto out;

        rc = asprintf(&env[2], "VDEV_UPATH=%s",
            data->upath ? data->upath : "");
        if (rc == -1)
                goto out;

        rc = asprintf(&env[3], "VDEV_ENC_SYSFS_PATH=%s",
            data->vdev_enc_sysfs_path ?
            data->vdev_enc_sysfs_path : "");
        if (rc == -1)
                goto out;

        /* Run the command */
        rc = libzfs_run_process_get_stdout_nopath(cmd, argv, env, &lines,
            &lines_cnt);
        if (rc != 0)
                goto out;

        /* Process the output we got */
        for (i = 0; i < lines_cnt; i++)
                if (vdev_process_cmd_output(data, lines[i]) != 0)
                        break;

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++)
                if (env[i] != NULL)
                        free(env[i]);
}

/*
 * Generate the search path for zpool iostat/status -c scripts.
 * The string returned must be freed.
 */
char *
zpool_get_cmd_search_path(void)
{
        const char *env;
        char *sp = NULL;

        env = getenv("ZPOOL_SCRIPTS_PATH");
        if (env != NULL)
                return (strdup(env));

        env = getenv("HOME");
        if (env != NULL) {
                if (asprintf(&sp, "%s/.zpool.d:%s",
                    env, ZPOOL_SCRIPTS_DIR) != -1) {
                        return (sp);
                }
        }

        if (asprintf(&sp, "%s", ZPOOL_SCRIPTS_DIR) != -1)
                return (sp);

        return (NULL);
}

/* Thread function run for each vdev */
static void
vdev_run_cmd_thread(void *cb_cmd_data)
{
        vdev_cmd_data_t *data = cb_cmd_data;
        char *cmd = NULL, *cmddup, *cmdrest;

        cmddup = strdup(data->cmd);
        if (cmddup == NULL)
                return;

        cmdrest = cmddup;
        while ((cmd = strtok_r(cmdrest, ",", &cmdrest))) {
                char *dir = NULL, *sp, *sprest;
                char fullpath[MAXPATHLEN];

                if (strchr(cmd, '/') != NULL)
                        continue;

                sp = zpool_get_cmd_search_path();
                if (sp == NULL)
                        continue;

                sprest = sp;
                while ((dir = strtok_r(sprest, ":", &sprest))) {
                        if (snprintf(fullpath, sizeof (fullpath),
                            "%s/%s", dir, cmd) == -1)
                                continue;

                        if (access(fullpath, X_OK) == 0) {
                                vdev_run_cmd(data, fullpath);
                                break;
                        }
                }
                free(sp);
        }
        free(cmddup);
}

/* For each vdev in the pool run a command */
static int
for_each_vdev_run_cb(zpool_handle_t *zhp, nvlist_t *nv, void *cb_vcdl)
{
        vdev_cmd_data_list_t *vcdl = cb_vcdl;
        vdev_cmd_data_t *data;
        char *path = NULL;
        char *vname = NULL;
        char *vdev_enc_sysfs_path = NULL;
        int i, match = 0;

        if (nvlist_lookup_string(nv, ZPOOL_CONFIG_PATH, &path) != 0)
                return (1);

        nvlist_lookup_string(nv, ZPOOL_CONFIG_VDEV_ENC_SYSFS_PATH,
            &vdev_enc_sysfs_path);

        /* Spares show more than once if they're in use, so skip if exists */
        for (i = 0; i < vcdl->count; i++) {
                if ((strcmp(vcdl->data[i].path, path) == 0) &&
                    (strcmp(vcdl->data[i].pool, zpool_get_name(zhp)) == 0)) {
                        /* vdev already exists, skip it */
                        return (0);
                }
        }

        /* Check for whitelisted vdevs here, if any */
        for (i = 0; i < vcdl->vdev_names_count; i++) {
                vname = zpool_vdev_name(g_zfs, zhp, nv, vcdl->cb_name_flags);
                if (strcmp(vcdl->vdev_names[i], vname) == 0) {
                        free(vname);
                        match = 1;
                        break; /* match */
                }
                free(vname);
        }

        /* If we whitelisted vdevs, and this isn't one of them, then bail out */
        if (!match && vcdl->vdev_names_count)
                return (0);

        /*
         * Resize our array and add in the new element.
         */
        if (!(vcdl->data = realloc(vcdl->data,
            sizeof (*vcdl->data) * (vcdl->count + 1))))
                return (ENOMEM);        /* couldn't realloc */

        data = &vcdl->data[vcdl->count];

        data->pool = strdup(zpool_get_name(zhp));
        data->path = strdup(path);
        data->upath = zfs_get_underlying_path(path);
        data->cmd = vcdl->cmd;
        data->lines = data->cols = NULL;
        data->lines_cnt = data->cols_cnt = 0;
        if (vdev_enc_sysfs_path)
                data->vdev_enc_sysfs_path = strdup(vdev_enc_sysfs_path);
        else
                data->vdev_enc_sysfs_path = NULL;

        vcdl->count++;

        return (0);
}

/* Get the names and count of the vdevs */
static int
all_pools_for_each_vdev_gather_cb(zpool_handle_t *zhp, void *cb_vcdl)
{
        return (for_each_vdev(zhp, for_each_vdev_run_cb, cb_vcdl));
}

/*
 * Now that vcdl is populated with our complete list of vdevs, spawn
 * off the commands.
 */
static void
all_pools_for_each_vdev_run_vcdl(vdev_cmd_data_list_t *vcdl)
{
        tpool_t *t;

        t = tpool_create(1, 5 * sysconf(_SC_NPROCESSORS_ONLN), 0, NULL);
        if (t == NULL)
                return;

        /* Spawn off the command for each vdev */
        for (int i = 0; i < vcdl->count; i++) {
                (void) tpool_dispatch(t, vdev_run_cmd_thread,
                    (void *) &vcdl->data[i]);
        }

        /* Wait for threads to finish */
        tpool_wait(t);
        tpool_destroy(t);
}

/*
 * Run command 'cmd' on all vdevs in all pools in argv.  Saves the first line of
 * output from the command in vcdk->data[].line for all vdevs.  If you want
 * to run the command on only certain vdevs, fill in g_zfs, vdev_names,
 * vdev_names_count, and cb_name_flags.  Otherwise leave them as zero.
 *
 * Returns a vdev_cmd_data_list_t that must be freed with
 * free_vdev_cmd_data_list();
 */
vdev_cmd_data_list_t *
all_pools_for_each_vdev_run(int argc, char **argv, char *cmd,
    libzfs_handle_t *g_zfs, char **vdev_names, int vdev_names_count,
    int cb_name_flags)
{
        vdev_cmd_data_list_t *vcdl;
        vcdl = safe_malloc(sizeof (vdev_cmd_data_list_t));
        vcdl->cmd = cmd;

        vcdl->vdev_names = vdev_names;
        vcdl->vdev_names_count = vdev_names_count;
        vcdl->cb_name_flags = cb_name_flags;
        vcdl->g_zfs = g_zfs;

        /* Gather our list of all vdevs in all pools */
        for_each_pool(argc, argv, B_TRUE, NULL,
            all_pools_for_each_vdev_gather_cb, vcdl);

        /* Run command on all vdevs in all pools */
        all_pools_for_each_vdev_run_vcdl(vcdl);

        /*
         * vcdl->data[] now contains all the column names and values for each
         * vdev.  We need to process that into a master list of unique column
         * names, and figure out the width of each column.
         */
        process_unique_cmd_columns(vcdl);

        return (vcdl);
}

/*
 * Free the vdev_cmd_data_list_t created by all_pools_for_each_vdev_run()
 */
void
free_vdev_cmd_data_list(vdev_cmd_data_list_t *vcdl)
{
        free(vcdl->uniq_cols);
        free(vcdl->uniq_cols_width);

        for (int i = 0; i < vcdl->count; i++) {
                free(vcdl->data[i].path);
                free(vcdl->data[i].pool);
                free(vcdl->data[i].upath);

                for (int j = 0; j < vcdl->data[i].lines_cnt; j++)
                        free(vcdl->data[i].lines[j]);

                free(vcdl->data[i].lines);

                for (int j = 0; j < vcdl->data[i].cols_cnt; j++)
                        free(vcdl->data[i].cols[j]);

                free(vcdl->data[i].cols);
                free(vcdl->data[i].vdev_enc_sysfs_path);
        }
        free(vcdl->data);
        free(vcdl);
}