btrfs-progs: docs: add note about mount option applicability

[btrfs-progs-unstable/devel.git] / cmds-filesystem.c

/*
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public
 * License v2 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public
 * License along with this program; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 021110-1307, USA.
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <errno.h>
#include <uuid/uuid.h>
#include <ctype.h>
#include <fcntl.h>
#include <ftw.h>
#include <mntent.h>
#include <linux/limits.h>
#include <getopt.h>

#include "kerncompat.h"
#include "ctree.h"
#include "utils.h"
#include "volumes.h"
#include "commands.h"
#include "cmds-fi-usage.h"
#include "list_sort.h"
#include "disk-io.h"
#include "help.h"

/*
 * for btrfs fi show, we maintain a hash of fsids we've already printed.
 * This way we don't print dups if a given FS is mounted more than once.
 */
static struct seen_fsid *seen_fsid_hash[SEEN_FSID_HASH_SIZE] = {NULL,};

static const char * const filesystem_cmd_group_usage[] = {
        "btrfs filesystem [<group>] <command> [<args>]",
        NULL
};

static const char * const cmd_filesystem_df_usage[] = {
        "btrfs filesystem df [options] <path>",
        "Show space usage information for a mount point",
        HELPINFO_UNITS_SHORT_LONG,
        NULL
};

static int get_df(int fd, struct btrfs_ioctl_space_args **sargs_ret)
{
        u64 count = 0;
        int ret;
        struct btrfs_ioctl_space_args *sargs;

        sargs = malloc(sizeof(struct btrfs_ioctl_space_args));
        if (!sargs)
                return -ENOMEM;

        sargs->space_slots = 0;
        sargs->total_spaces = 0;

        ret = ioctl(fd, BTRFS_IOC_SPACE_INFO, sargs);
        if (ret < 0) {
                error("cannot get space info: %s", strerror(errno));
                free(sargs);
                return -errno;
        }
        /* This really should never happen */
        if (!sargs->total_spaces) {
                free(sargs);
                return -ENOENT;
        }
        count = sargs->total_spaces;
        free(sargs);

        sargs = malloc(sizeof(struct btrfs_ioctl_space_args) +
                        (count * sizeof(struct btrfs_ioctl_space_info)));
        if (!sargs)
                return -ENOMEM;

        sargs->space_slots = count;
        sargs->total_spaces = 0;
        ret = ioctl(fd, BTRFS_IOC_SPACE_INFO, sargs);
        if (ret < 0) {
                error("cannot get space info with %llu slots: %s",
                                count, strerror(errno));
                free(sargs);
                return -errno;
        }
        *sargs_ret = sargs;
        return 0;
}

static void print_df(struct btrfs_ioctl_space_args *sargs, unsigned unit_mode)
{
        u64 i;
        struct btrfs_ioctl_space_info *sp = sargs->spaces;

        for (i = 0; i < sargs->total_spaces; i++, sp++) {
                printf("%s, %s: total=%s, used=%s\n",
                        btrfs_group_type_str(sp->flags),
                        btrfs_group_profile_str(sp->flags),
                        pretty_size_mode(sp->total_bytes, unit_mode),
                        pretty_size_mode(sp->used_bytes, unit_mode));
        }
}

static int cmd_filesystem_df(int argc, char **argv)
{
        struct btrfs_ioctl_space_args *sargs = NULL;
        int ret;
        int fd;
        char *path;
        DIR *dirstream = NULL;
        unsigned unit_mode;

        unit_mode = get_unit_mode_from_arg(&argc, argv, 1);

        clean_args_no_options(argc, argv, cmd_filesystem_df_usage);

        if (check_argc_exact(argc - optind, 1))
                usage(cmd_filesystem_df_usage);

        path = argv[optind];

        fd = btrfs_open_dir(path, &dirstream, 1);
        if (fd < 0)
                return 1;

        ret = get_df(fd, &sargs);

        if (ret == 0) {
                print_df(sargs, unit_mode);
                free(sargs);
        } else {
                error("get_df failed %s", strerror(-ret));
        }

        close_file_or_dir(fd, dirstream);
        return !!ret;
}

static int match_search_item_kernel(u8 *fsid, char *mnt, char *label,
                                        char *search)
{
        char uuidbuf[BTRFS_UUID_UNPARSED_SIZE];
        int search_len = strlen(search);

        search_len = min(search_len, BTRFS_UUID_UNPARSED_SIZE);
        uuid_unparse(fsid, uuidbuf);
        if (!strncmp(uuidbuf, search, search_len))
                return 1;

        if (*label && strcmp(label, search) == 0)
                return 1;

        if (strcmp(mnt, search) == 0)
                return 1;

        return 0;
}

static int uuid_search(struct btrfs_fs_devices *fs_devices, const char *search)
{
        char uuidbuf[BTRFS_UUID_UNPARSED_SIZE];
        struct list_head *cur;
        struct btrfs_device *device;
        int search_len = strlen(search);

        search_len = min(search_len, BTRFS_UUID_UNPARSED_SIZE);
        uuid_unparse(fs_devices->fsid, uuidbuf);
        if (!strncmp(uuidbuf, search, search_len))
                return 1;

        list_for_each(cur, &fs_devices->devices) {
                device = list_entry(cur, struct btrfs_device, dev_list);
                if ((device->label && strcmp(device->label, search) == 0) ||
                    strcmp(device->name, search) == 0)
                        return 1;
        }
        return 0;
}

/*
 * Sort devices by devid, ascending
 */
static int cmp_device_id(void *priv, struct list_head *a,
                struct list_head *b)
{
        const struct btrfs_device *da = list_entry(a, struct btrfs_device,
                        dev_list);
        const struct btrfs_device *db = list_entry(b, struct btrfs_device,
                        dev_list);

        return da->devid < db->devid ? -1 :
                da->devid > db->devid ? 1 : 0;
}

static void splice_device_list(struct list_head *seed_devices,
                               struct list_head *all_devices)
{
        struct btrfs_device *in_all, *next_all;
        struct btrfs_device *in_seed, *next_seed;

        list_for_each_entry_safe(in_all, next_all, all_devices, dev_list) {
                list_for_each_entry_safe(in_seed, next_seed, seed_devices,
                                                                dev_list) {
                        if (in_all->devid == in_seed->devid) {
                                /*
                                 * When do dev replace in a sprout fs
                                 * to a dev in its seed fs, the replacing
                                 * dev will reside in the sprout fs and
                                 * the replaced dev will still exist
                                 * in the seed fs.
                                 * So pick the latest one when showing
                                 * the sprout fs.
                                 */
                                if (in_all->generation
                                                < in_seed->generation) {
                                        list_del(&in_all->dev_list);
                                        free(in_all);
                                } else if (in_all->generation
                                                > in_seed->generation) {
                                        list_del(&in_seed->dev_list);
                                        free(in_seed);
                                }
                                break;
                        }
                }
        }

        list_splice(seed_devices, all_devices);
}

static void print_devices(struct btrfs_fs_devices *fs_devices,
                          u64 *devs_found, unsigned unit_mode)
{
        struct btrfs_device *device;
        struct btrfs_fs_devices *cur_fs;
        struct list_head *all_devices;

        all_devices = &fs_devices->devices;
        cur_fs = fs_devices->seed;
        /* add all devices of seed fs to the fs to be printed */
        while (cur_fs) {
                splice_device_list(&cur_fs->devices, all_devices);
                cur_fs = cur_fs->seed;
        }

        list_sort(NULL, all_devices, cmp_device_id);
        list_for_each_entry(device, all_devices, dev_list) {
                printf("\tdevid %4llu size %s used %s path %s\n",
                       (unsigned long long)device->devid,
                       pretty_size_mode(device->total_bytes, unit_mode),
                       pretty_size_mode(device->bytes_used, unit_mode),
                       device->name);

                (*devs_found)++;
        }
}

static void print_one_uuid(struct btrfs_fs_devices *fs_devices,
                           unsigned unit_mode)
{
        char uuidbuf[BTRFS_UUID_UNPARSED_SIZE];
        struct btrfs_device *device;
        u64 devs_found = 0;
        u64 total;

        if (add_seen_fsid(fs_devices->fsid, seen_fsid_hash, -1, NULL))
                return;

        uuid_unparse(fs_devices->fsid, uuidbuf);
        device = list_entry(fs_devices->devices.next, struct btrfs_device,
                            dev_list);
        if (device->label && device->label[0])
                printf("Label: '%s' ", device->label);
        else
                printf("Label: none ");

        total = device->total_devs;
        printf(" uuid: %s\n\tTotal devices %llu FS bytes used %s\n", uuidbuf,
               (unsigned long long)total,
               pretty_size_mode(device->super_bytes_used, unit_mode));

        print_devices(fs_devices, &devs_found, unit_mode);

        if (devs_found < total) {
                printf("\t*** Some devices missing\n");
        }
        printf("\n");
}

/* adds up all the used spaces as reported by the space info ioctl
 */
static u64 calc_used_bytes(struct btrfs_ioctl_space_args *si)
{
        u64 ret = 0;
        int i;
        for (i = 0; i < si->total_spaces; i++)
                ret += si->spaces[i].used_bytes;
        return ret;
}

static int print_one_fs(struct btrfs_ioctl_fs_info_args *fs_info,
                struct btrfs_ioctl_dev_info_args *dev_info,
                struct btrfs_ioctl_space_args *space_info,
                char *label, unsigned unit_mode)
{
        int i;
        int fd;
        int missing = 0;
        char uuidbuf[BTRFS_UUID_UNPARSED_SIZE];
        struct btrfs_ioctl_dev_info_args *tmp_dev_info;
        int ret;

        ret = add_seen_fsid(fs_info->fsid, seen_fsid_hash, -1, NULL);
        if (ret == -EEXIST)
                return 0;
        else if (ret)
                return ret;

        uuid_unparse(fs_info->fsid, uuidbuf);
        if (label && *label)
                printf("Label: '%s' ", label);
        else
                printf("Label: none ");

        printf(" uuid: %s\n\tTotal devices %llu FS bytes used %s\n", uuidbuf,
                        fs_info->num_devices,
                        pretty_size_mode(calc_used_bytes(space_info),
                                         unit_mode));

        for (i = 0; i < fs_info->num_devices; i++) {
                char *canonical_path;

                tmp_dev_info = (struct btrfs_ioctl_dev_info_args *)&dev_info[i];

                /* Add check for missing devices even mounted */
                fd = open((char *)tmp_dev_info->path, O_RDONLY);
                if (fd < 0) {
                        missing = 1;
                        continue;
                }
                close(fd);
                canonical_path = canonicalize_path((char *)tmp_dev_info->path);
                printf("\tdevid %4llu size %s used %s path %s\n",
                        tmp_dev_info->devid,
                        pretty_size_mode(tmp_dev_info->total_bytes, unit_mode),
                        pretty_size_mode(tmp_dev_info->bytes_used, unit_mode),
                        canonical_path);

                free(canonical_path);
        }

        if (missing)
                printf("\t*** Some devices missing\n");
        printf("\n");
        return 0;
}

static int btrfs_scan_kernel(void *search, unsigned unit_mode)
{
        int ret = 0, fd;
        int found = 0;
        FILE *f;
        struct mntent *mnt;
        struct btrfs_ioctl_fs_info_args fs_info_arg;
        struct btrfs_ioctl_dev_info_args *dev_info_arg = NULL;
        struct btrfs_ioctl_space_args *space_info_arg = NULL;
        char label[BTRFS_LABEL_SIZE];

        f = setmntent("/proc/self/mounts", "r");
        if (f == NULL)
                return 1;

        memset(label, 0, sizeof(label));
        while ((mnt = getmntent(f)) != NULL) {
                free(dev_info_arg);
                dev_info_arg = NULL;
                if (strcmp(mnt->mnt_type, "btrfs"))
                        continue;
                ret = get_fs_info(mnt->mnt_dir, &fs_info_arg,
                                &dev_info_arg);
                if (ret)
                        goto out;

                /* skip all fs already shown as mounted fs */
                if (is_seen_fsid(fs_info_arg.fsid, seen_fsid_hash))
                        continue;

                ret = get_label_mounted(mnt->mnt_dir, label);
                /* provide backward kernel compatibility */
                if (ret == -ENOTTY)
                        ret = get_label_unmounted(
                                (const char *)dev_info_arg->path, label);

                if (ret)
                        goto out;

                if (search && !match_search_item_kernel(fs_info_arg.fsid,
                                        mnt->mnt_dir, label, search)) {
                        continue;
                }

                fd = open(mnt->mnt_dir, O_RDONLY);
                if ((fd != -1) && !get_df(fd, &space_info_arg)) {
                        print_one_fs(&fs_info_arg, dev_info_arg,
                                     space_info_arg, label, unit_mode);
                        free(space_info_arg);
                        memset(label, 0, sizeof(label));
                        found = 1;
                }
                if (fd != -1)
                        close(fd);
        }

out:
        free(dev_info_arg);
        endmntent(f);
        return !found;
}

static void free_fs_devices(struct btrfs_fs_devices *fs_devices)
{
        struct btrfs_fs_devices *cur_seed, *next_seed;
        struct btrfs_device *device;

        while (!list_empty(&fs_devices->devices)) {
                device = list_entry(fs_devices->devices.next,
                                        struct btrfs_device, dev_list);
                list_del(&device->dev_list);

                free(device->name);
                free(device->label);
                free(device);
        }

        /* free seed fs chain */
        cur_seed = fs_devices->seed;
        fs_devices->seed = NULL;
        while (cur_seed) {
                next_seed = cur_seed->seed;
                free(cur_seed);

                cur_seed = next_seed;
        }

        list_del(&fs_devices->list);
        free(fs_devices);
}

static int copy_device(struct btrfs_device *dst,
                       struct btrfs_device *src)
{
        dst->devid = src->devid;
        memcpy(dst->uuid, src->uuid, BTRFS_UUID_SIZE);
        if (src->name == NULL)
                dst->name = NULL;
        else {
                dst->name = strdup(src->name);
                if (!dst->name)
                        return -ENOMEM;
        }
        if (src->label == NULL)
                dst->label = NULL;
        else {
                dst->label = strdup(src->label);
                if (!dst->label) {
                        free(dst->name);
                        return -ENOMEM;
                }
        }
        dst->total_devs = src->total_devs;
        dst->super_bytes_used = src->super_bytes_used;
        dst->total_bytes = src->total_bytes;
        dst->bytes_used = src->bytes_used;
        dst->generation = src->generation;

        return 0;
}

static int copy_fs_devices(struct btrfs_fs_devices *dst,
                           struct btrfs_fs_devices *src)
{
        struct btrfs_device *cur_dev, *dev_copy;
        int ret = 0;

        memcpy(dst->fsid, src->fsid, BTRFS_FSID_SIZE);
        INIT_LIST_HEAD(&dst->devices);
        dst->seed = NULL;

        list_for_each_entry(cur_dev, &src->devices, dev_list) {
                dev_copy = malloc(sizeof(*dev_copy));
                if (!dev_copy) {
                        ret = -ENOMEM;
                        break;
                }

                ret = copy_device(dev_copy, cur_dev);
                if (ret) {
                        free(dev_copy);
                        break;
                }

                list_add(&dev_copy->dev_list, &dst->devices);
                dev_copy->fs_devices = dst;
        }

        return ret;
}

static int find_and_copy_seed(struct btrfs_fs_devices *seed,
                              struct btrfs_fs_devices *copy,
                              struct list_head *fs_uuids) {
        struct btrfs_fs_devices *cur_fs;

        list_for_each_entry(cur_fs, fs_uuids, list)
                if (!memcmp(seed->fsid, cur_fs->fsid, BTRFS_FSID_SIZE))
                        return copy_fs_devices(copy, cur_fs);

        return 1;
}

static int has_seed_devices(struct btrfs_fs_devices *fs_devices)
{
        struct btrfs_device *device;
        int dev_cnt_total, dev_cnt = 0;

        device = list_first_entry(&fs_devices->devices, struct btrfs_device,
                                  dev_list);

        dev_cnt_total = device->total_devs;

        list_for_each_entry(device, &fs_devices->devices, dev_list)
                dev_cnt++;

        return dev_cnt_total != dev_cnt;
}

static int search_umounted_fs_uuids(struct list_head *all_uuids,
                                    char *search, int *found)
{
        struct btrfs_fs_devices *cur_fs, *fs_copy;
        struct list_head *fs_uuids;
        int ret = 0;

        fs_uuids = btrfs_scanned_uuids();

        /*
         * The fs_uuids list is global, and open_ctree_* will
         * modify it, make a private copy here
         */
        list_for_each_entry(cur_fs, fs_uuids, list) {
                /* don't bother handle all fs, if search target specified */
                if (search) {
                        if (uuid_search(cur_fs, search) == 0)
                                continue;
                        if (found)
                                *found = 1;
                }

                /* skip all fs already shown as mounted fs */
                if (is_seen_fsid(cur_fs->fsid, seen_fsid_hash))
                        continue;

                fs_copy = calloc(1, sizeof(*fs_copy));
                if (!fs_copy) {
                        ret = -ENOMEM;
                        goto out;
                }

                ret = copy_fs_devices(fs_copy, cur_fs);
                if (ret) {
                        free(fs_copy);
                        goto out;
                }

                list_add(&fs_copy->list, all_uuids);
        }

out:
        return ret;
}

static int map_seed_devices(struct list_head *all_uuids)
{
        struct btrfs_fs_devices *cur_fs, *cur_seed;
        struct btrfs_fs_devices *seed_copy;
        struct btrfs_fs_devices *opened_fs;
        struct btrfs_device *device;
        struct btrfs_fs_info *fs_info;
        struct list_head *fs_uuids;
        int ret = 0;

        fs_uuids = btrfs_scanned_uuids();

        list_for_each_entry(cur_fs, all_uuids, list) {
                device = list_first_entry(&cur_fs->devices,
                                                struct btrfs_device, dev_list);
                if (!device)
                        continue;

                /* skip fs without seeds */
                if (!has_seed_devices(cur_fs))
                        continue;

                /*
                 * open_ctree_* detects seed/sprout mapping
                 */
                fs_info = open_ctree_fs_info(device->name, 0, 0, 0,
                                                OPEN_CTREE_PARTIAL);
                if (!fs_info)
                        continue;

                /*
                 * copy the seed chain under the opened fs
                 */
                opened_fs = fs_info->fs_devices;
                cur_seed = cur_fs;
                while (opened_fs->seed) {
                        seed_copy = malloc(sizeof(*seed_copy));
                        if (!seed_copy) {
                                ret = -ENOMEM;
                                goto fail_out;
                        }
                        ret = find_and_copy_seed(opened_fs->seed, seed_copy,
                                                 fs_uuids);
                        if (ret) {
                                free(seed_copy);
                                goto fail_out;
                        }

                        cur_seed->seed = seed_copy;

                        opened_fs = opened_fs->seed;
                        cur_seed = cur_seed->seed;
                }

                close_ctree(fs_info->chunk_root);
        }

out:
        return ret;
fail_out:
        close_ctree(fs_info->chunk_root);
        goto out;
}

static const char * const cmd_filesystem_show_usage[] = {
        "btrfs filesystem show [options] [<path>|<uuid>|<device>|label]",
        "Show the structure of a filesystem",
        "-d|--all-devices   show only disks under /dev containing btrfs filesystem",
        "-m|--mounted       show only mounted btrfs",
        HELPINFO_UNITS_LONG,
        "If no argument is given, structure of all present filesystems is shown.",
        NULL
};

static int cmd_filesystem_show(int argc, char **argv)
{
        LIST_HEAD(all_uuids);
        struct btrfs_fs_devices *fs_devices;
        char *search = NULL;
        int ret;
        /* default, search both kernel and udev */
        int where = -1;
        int type = 0;
        char mp[PATH_MAX];
        char path[PATH_MAX];
        u8 fsid[BTRFS_FSID_SIZE];
        char uuid_buf[BTRFS_UUID_UNPARSED_SIZE];
        unsigned unit_mode;
        int found = 0;

        unit_mode = get_unit_mode_from_arg(&argc, argv, 0);

        while (1) {
                int c;
                static const struct option long_options[] = {
                        { "all-devices", no_argument, NULL, 'd'},
                        { "mounted", no_argument, NULL, 'm'},
                        { NULL, 0, NULL, 0 }
                };

                c = getopt_long(argc, argv, "dm", long_options, NULL);
                if (c < 0)
                        break;
                switch (c) {
                case 'd':
                        where = BTRFS_SCAN_LBLKID;
                        break;
                case 'm':
                        where = BTRFS_SCAN_MOUNTED;
                        break;
                default:
                        usage(cmd_filesystem_show_usage);
                }
        }

        if (check_argc_max(argc, optind + 1))
                usage(cmd_filesystem_show_usage);

        if (argc > optind) {
                search = argv[optind];
                if (*search == 0)
                        usage(cmd_filesystem_show_usage);
                type = check_arg_type(search);

                /*
                 * For search is a device:
                 *     realpath do /dev/mapper/XX => /dev/dm-X
                 *     which is required by BTRFS_SCAN_DEV
                 * For search is a mountpoint:
                 *     realpath do  /mnt/btrfs/  => /mnt/btrfs
                 *     which shall be recognized by btrfs_scan_kernel()
                 */
                if (realpath(search, path))
                        search = path;

                /*
                 * Needs special handling if input arg is block dev And if
                 * input arg is mount-point just print it right away
                 */
                if (type == BTRFS_ARG_BLKDEV && where != BTRFS_SCAN_LBLKID) {
                        ret = get_btrfs_mount(search, mp, sizeof(mp));
                        if (!ret) {
                                /* given block dev is mounted */
                                search = mp;
                                type = BTRFS_ARG_MNTPOINT;
                        } else {
                                ret = dev_to_fsid(search, fsid);
                                if (ret) {
                                        error("no btrfs on %s", search);
                                        return 1;
                                }
                                uuid_unparse(fsid, uuid_buf);
                                search = uuid_buf;
                                type = BTRFS_ARG_UUID;
                                goto devs_only;
                        }
                }
        }

        if (where == BTRFS_SCAN_LBLKID)
                goto devs_only;

        /* show mounted btrfs */
        ret = btrfs_scan_kernel(search, unit_mode);
        if (search && !ret) {
                /* since search is found we are done */
                goto out;
        }

        /* shows mounted only */
        if (where == BTRFS_SCAN_MOUNTED)
                goto out;

devs_only:
        ret = btrfs_scan_devices();

        if (ret) {
                error("blkid device scan returned %d", ret);
                return 1;
        }

        ret = search_umounted_fs_uuids(&all_uuids, search, &found);
        if (ret < 0) {
                error("searching target device returned error %d", ret);
                return 1;
        }

        /*
         * The seed/sprout mapping are not detected yet,
         * do mapping build for all umounted fs
         */
        ret = map_seed_devices(&all_uuids);
        if (ret) {
                error("mapping seed devices returned error %d", ret);
                return 1;
        }

        list_for_each_entry(fs_devices, &all_uuids, list)
                print_one_uuid(fs_devices, unit_mode);

        if (search && !found) {
                error("not a valid btrfs filesystem: %s", search);
                ret = 1;
        }
        while (!list_empty(&all_uuids)) {
                fs_devices = list_entry(all_uuids.next,
                                        struct btrfs_fs_devices, list);
                free_fs_devices(fs_devices);
        }
out:
        free_seen_fsid(seen_fsid_hash);
        return ret;
}

static const char * const cmd_filesystem_sync_usage[] = {
        "btrfs filesystem sync <path>",
        "Force a sync on a filesystem",
        NULL
};

static int cmd_filesystem_sync(int argc, char **argv)
{
        int     fd, res, e;
        char    *path;
        DIR     *dirstream = NULL;

        clean_args_no_options(argc, argv, cmd_filesystem_sync_usage);

        if (check_argc_exact(argc - optind, 1))
                usage(cmd_filesystem_sync_usage);

        path = argv[optind];

        fd = btrfs_open_dir(path, &dirstream, 1);
        if (fd < 0)
                return 1;

        res = ioctl(fd, BTRFS_IOC_SYNC);
        e = errno;
        close_file_or_dir(fd, dirstream);
        if( res < 0 ){
                error("sync ioctl failed on '%s': %s", path, strerror(e));
                return 1;
        }

        return 0;
}

static int parse_compress_type(char *s)
{
        if (strcmp(optarg, "zlib") == 0)
                return BTRFS_COMPRESS_ZLIB;
        else if (strcmp(optarg, "lzo") == 0)
                return BTRFS_COMPRESS_LZO;
        else if (strcmp(optarg, "zstd") == 0)
                return BTRFS_COMPRESS_ZSTD;
        else {
                error("unknown compression type %s", s);
                exit(1);
        };
}

static const char * const cmd_filesystem_defrag_usage[] = {
        "btrfs filesystem defragment [options] <file>|<dir> [<file>|<dir>...]",
        "Defragment a file or a directory",
        "",
        "-v                  be verbose",
        "-r                  defragment files recursively",
        "-c[zlib,lzo,zstd]   compress the file while defragmenting",
        "-f                  flush data to disk immediately after defragmenting",
        "-s start            defragment only from byte onward",
        "-l len              defragment only up to len bytes",
        "-t size             target extent size hint (default: 32M)",
        "",
        "Warning: most Linux kernels will break up the ref-links of COW data",
        "(e.g., files copied with 'cp --reflink', snapshots) which may cause",
        "considerable increase of space usage. See btrfs-filesystem(8) for",
        "more information.",
        NULL
};

static struct btrfs_ioctl_defrag_range_args defrag_global_range;
static int defrag_global_verbose;
static int defrag_global_errors;
static int defrag_callback(const char *fpath, const struct stat *sb,
                int typeflag, struct FTW *ftwbuf)
{
        int ret = 0;
        int err = 0;
        int fd = 0;

        if ((typeflag == FTW_F) && S_ISREG(sb->st_mode)) {
                if (defrag_global_verbose)
                        printf("%s\n", fpath);
                fd = open(fpath, O_RDWR);
                if (fd < 0) {
                        err = errno;
                        goto error;
                }
                ret = ioctl(fd, BTRFS_IOC_DEFRAG_RANGE, &defrag_global_range);
                close(fd);
                if (ret && errno == ENOTTY) {
                        error(
"defrag range ioctl not supported in this kernel version, 2.6.33 and newer is required");
                        defrag_global_errors++;
                        return ENOTTY;
                }
                if (ret) {
                        err = errno;
                        goto error;
                }
        }
        return 0;

error:
        error("defrag failed on %s: %s", fpath, strerror(err));
        defrag_global_errors++;
        return 0;
}

static int cmd_filesystem_defrag(int argc, char **argv)
{
        int fd;
        int flush = 0;
        u64 start = 0;
        u64 len = (u64)-1;
        u64 thresh;
        int i;
        int recursive = 0;
        int ret = 0;
        int compress_type = BTRFS_COMPRESS_NONE;
        DIR *dirstream;

        /*
         * Kernel has a different default (256K) that is supposed to be safe,
         * but it does not defragment very well. The 32M will likely lead to
         * better results and is independent of the kernel default. We have to
         * use the v2 defrag ioctl.
         */
        thresh = SZ_32M;

        defrag_global_errors = 0;
        defrag_global_verbose = 0;
        defrag_global_errors = 0;
        while(1) {
                int c = getopt(argc, argv, "vrc::fs:l:t:");
                if (c < 0)
                        break;

                switch(c) {
                case 'c':
                        compress_type = BTRFS_COMPRESS_ZLIB;
                        if (optarg)
                                compress_type = parse_compress_type(optarg);
                        break;
                case 'f':
                        flush = 1;
                        break;
                case 'v':
                        defrag_global_verbose = 1;
                        break;
                case 's':
                        start = parse_size(optarg);
                        break;
                case 'l':
                        len = parse_size(optarg);
                        break;
                case 't':
                        thresh = parse_size(optarg);
                        if (thresh > (u32)-1) {
                                warning(
                            "target extent size %llu too big, trimmed to %u",
                                        thresh, (u32)-1);
                                thresh = (u32)-1;
                        }
                        break;
                case 'r':
                        recursive = 1;
                        break;
                default:
                        usage(cmd_filesystem_defrag_usage);
                }
        }

        if (check_argc_min(argc - optind, 1))
                usage(cmd_filesystem_defrag_usage);

        memset(&defrag_global_range, 0, sizeof(defrag_global_range));
        defrag_global_range.start = start;
        defrag_global_range.len = len;
        defrag_global_range.extent_thresh = (u32)thresh;
        if (compress_type) {
                defrag_global_range.flags |= BTRFS_DEFRAG_RANGE_COMPRESS;
                defrag_global_range.compress_type = compress_type;
        }
        if (flush)
                defrag_global_range.flags |= BTRFS_DEFRAG_RANGE_START_IO;

        /*
         * Look for directory arguments and warn if the recursive mode is not
         * requested, as this is not implemented as recursive defragmentation
         * in kernel. The stat errors are silent here as we check them below.
         */
        if (!recursive) {
                int found = 0;

                for (i = optind; i < argc; i++) {
                        struct stat st;

                        if (stat(argv[i], &st))
                                continue;

                        if (S_ISDIR(st.st_mode)) {
                                warning(
                        "directory specified but recursive mode not requested: %s",
                                        argv[i]);
                                found = 1;
                        }
                }
                if (found) {
                        warning(
"a directory passed to the defrag ioctl will not process the files\n"
"recursively but will defragment the subvolume tree and the extent tree.\n"
"If this is not intended, please use option -r .");
                }
        }

        for (i = optind; i < argc; i++) {
                struct stat st;
                int defrag_err = 0;

                dirstream = NULL;
                fd = open_file_or_dir(argv[i], &dirstream);
                if (fd < 0) {
                        error("cannot open %s: %s", argv[i],
                                        strerror(errno));
                        defrag_global_errors++;
                        close_file_or_dir(fd, dirstream);
                        continue;
                }
                if (fstat(fd, &st)) {
                        error("failed to stat %s: %s",
                                        argv[i], strerror(errno));
                        defrag_global_errors++;
                        close_file_or_dir(fd, dirstream);
                        continue;
                }
                if (!(S_ISDIR(st.st_mode) || S_ISREG(st.st_mode))) {
                        error("%s is not a directory or a regular file",
                                        argv[i]);
                        defrag_global_errors++;
                        close_file_or_dir(fd, dirstream);
                        continue;
                }
                if (recursive && S_ISDIR(st.st_mode)) {
                        ret = nftw(argv[i], defrag_callback, 10,
                                                FTW_MOUNT | FTW_PHYS);
                        if (ret == ENOTTY)
                                exit(1);
                        /* errors are handled in the callback */
                        ret = 0;
                } else {
                        if (defrag_global_verbose)
                                printf("%s\n", argv[i]);
                        ret = ioctl(fd, BTRFS_IOC_DEFRAG_RANGE,
                                        &defrag_global_range);
                        defrag_err = errno;
                }
                close_file_or_dir(fd, dirstream);
                if (ret && defrag_err == ENOTTY) {
                        error(
"defrag range ioctl not supported in this kernel version, 2.6.33 and newer is required");
                        defrag_global_errors++;
                        break;
                }
                if (ret) {
                        error("defrag failed on %s: %s", argv[i],
                                        strerror(defrag_err));
                        defrag_global_errors++;
                }
        }
        if (defrag_global_errors)
                fprintf(stderr, "total %d failures\n", defrag_global_errors);

        return !!defrag_global_errors;
}

static const char * const cmd_filesystem_resize_usage[] = {
        "btrfs filesystem resize [devid:][+/-]<newsize>[kKmMgGtTpPeE]|[devid:]max <path>",
        "Resize a filesystem",
        "If 'max' is passed, the filesystem will occupy all available space",
        "on the device 'devid'.",
        "[kK] means KiB, which denotes 1KiB = 1024B, 1MiB = 1024KiB, etc.",
        NULL
};

static int cmd_filesystem_resize(int argc, char **argv)
{
        struct btrfs_ioctl_vol_args     args;
        int     fd, res, len, e;
        char    *amount, *path;
        DIR     *dirstream = NULL;
        struct stat st;

        clean_args_no_options_relaxed(argc, argv, cmd_filesystem_resize_usage);

        if (check_argc_exact(argc - optind, 2))
                usage(cmd_filesystem_resize_usage);

        amount = argv[optind];
        path = argv[optind + 1];

        len = strlen(amount);
        if (len == 0 || len >= BTRFS_VOL_NAME_MAX) {
                error("resize value too long (%s)", amount);
                return 1;
        }

        res = stat(path, &st);
        if (res < 0) {
                error("resize: cannot stat %s: %s", path, strerror(errno));
                return 1;
        }
        if (!S_ISDIR(st.st_mode)) {
                error("resize works on mounted filesystems and accepts only\n"
                        "directories as argument. Passing file containing a btrfs image\n"
                        "would resize the underlying filesystem instead of the image.\n");
                return 1;
        }

        fd = btrfs_open_dir(path, &dirstream, 1);
        if (fd < 0)
                return 1;

        printf("Resize '%s' of '%s'\n", path, amount);
        memset(&args, 0, sizeof(args));
        strncpy_null(args.name, amount);
        res = ioctl(fd, BTRFS_IOC_RESIZE, &args);
        e = errno;
        close_file_or_dir(fd, dirstream);
        if( res < 0 ){
                switch (e) {
                case EFBIG:
                        error("unable to resize '%s': no enough free space",
                                path);
                        break;
                default:
                        error("unable to resize '%s': %s", path, strerror(e));
                        break;
                }
                return 1;
        } else if (res > 0) {
                const char *err_str = btrfs_err_str(res);

                if (err_str) {
                        error("resizing of '%s' failed: %s", path, err_str);
                } else {
                        error("resizing of '%s' failed: unknown error %d",
                                path, res);
                }
                return 1;
        }
        return 0;
}

static const char * const cmd_filesystem_label_usage[] = {
        "btrfs filesystem label [<device>|<mount_point>] [<newlabel>]",
        "Get or change the label of a filesystem",
        "With one argument, get the label of filesystem on <device>.",
        "If <newlabel> is passed, set the filesystem label to <newlabel>.",
        NULL
};

static int cmd_filesystem_label(int argc, char **argv)
{
        clean_args_no_options(argc, argv, cmd_filesystem_label_usage);

        if (check_argc_min(argc - optind, 1) ||
                        check_argc_max(argc - optind, 2))
                usage(cmd_filesystem_label_usage);

        if (argc - optind > 1) {
                return set_label(argv[optind], argv[optind + 1]);
        } else {
                char label[BTRFS_LABEL_SIZE];
                int ret;

                ret = get_label(argv[optind], label);
                if (!ret)
                        fprintf(stdout, "%s\n", label);

                return ret;
        }
}

static const char filesystem_cmd_group_info[] =
"overall filesystem tasks and information";

const struct cmd_group filesystem_cmd_group = {
        filesystem_cmd_group_usage, filesystem_cmd_group_info, {
                { "df", cmd_filesystem_df, cmd_filesystem_df_usage, NULL, 0 },
                { "du", cmd_filesystem_du, cmd_filesystem_du_usage, NULL, 0 },
                { "show", cmd_filesystem_show, cmd_filesystem_show_usage, NULL,
                        0 },
                { "sync", cmd_filesystem_sync, cmd_filesystem_sync_usage, NULL,
                        0 },
                { "defragment", cmd_filesystem_defrag,
                        cmd_filesystem_defrag_usage, NULL, 0 },
                { "balance", cmd_balance, NULL, &balance_cmd_group,
                        CMD_HIDDEN },
                { "resize", cmd_filesystem_resize, cmd_filesystem_resize_usage,
                        NULL, 0 },
                { "label", cmd_filesystem_label, cmd_filesystem_label_usage,
                        NULL, 0 },
                { "usage", cmd_filesystem_usage,
                        cmd_filesystem_usage_usage, NULL, 0 },

                NULL_CMD_STRUCT
        }
};

int cmd_filesystem(int argc, char **argv)
{
        return handle_command_group(&filesystem_cmd_group, argc, argv);
}