1402 lines
31 KiB
C
1402 lines
31 KiB
C
/*
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* Copyright (C) 2007 Oracle. All rights reserved.
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* Copyright (C) 2008 Morey Roof. All rights reserved.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public
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* License v2 as published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* General Public License for more details.
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*
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* You should have received a copy of the GNU General Public
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* License along with this program; if not, write to the
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* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
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* Boston, MA 021110-1307, USA.
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*/
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#include "kerncompat.h"
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#include <sys/ioctl.h>
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#include <sys/time.h>
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#include <sys/sysinfo.h>
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#include <sys/select.h>
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#include <sys/stat.h>
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#include <dirent.h>
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#include <errno.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <fcntl.h>
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#include <unistd.h>
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#include <mntent.h>
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#include <ctype.h>
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#include <limits.h>
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#include <strings.h>
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#include "kernel-lib/list.h"
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#include "kernel-shared/accessors.h"
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#include "kernel-shared/ctree.h"
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#include "kernel-shared/disk-io.h"
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#include "kernel-shared/volumes.h"
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#include "common/utils.h"
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#include "common/device-utils.h"
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#include "common/path-utils.h"
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#include "common/open-utils.h"
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#include "common/sysfs-utils.h"
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#include "common/messages.h"
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#include "common/tree-search.h"
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#include "cmds/commands.h"
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#include "mkfs/common.h"
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static int rand_seed_initialized = 0;
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static unsigned short rand_seed[3];
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struct btrfs_config bconf;
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struct pending_dir {
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struct list_head list;
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char name[PATH_MAX];
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};
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void btrfs_format_csum(u16 csum_type, const u8 *data, char *output)
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{
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int i;
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int cur = 0;
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const int csum_size = btrfs_csum_type_size(csum_type);
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output[0] = '\0';
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snprintf(output, BTRFS_CSUM_STRING_LEN, "0x");
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cur += strlen("0x");
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for (i = 0; i < csum_size; i++) {
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snprintf(output + cur, BTRFS_CSUM_STRING_LEN - cur, "%02x",
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data[i]);
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cur += 2;
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}
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}
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int get_df(int fd, struct btrfs_ioctl_space_args **sargs_ret)
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{
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u64 count = 0;
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int ret;
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struct btrfs_ioctl_space_args *sargs;
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sargs = malloc(sizeof(struct btrfs_ioctl_space_args));
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if (!sargs)
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return -ENOMEM;
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sargs->space_slots = 0;
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sargs->total_spaces = 0;
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ret = ioctl(fd, BTRFS_IOC_SPACE_INFO, sargs);
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if (ret < 0) {
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error("cannot get space info: %m");
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free(sargs);
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return -errno;
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}
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/* This really should never happen */
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if (!sargs->total_spaces) {
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free(sargs);
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return -ENOENT;
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}
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count = sargs->total_spaces;
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free(sargs);
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sargs = malloc(sizeof(struct btrfs_ioctl_space_args) +
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(count * sizeof(struct btrfs_ioctl_space_info)));
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if (!sargs)
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return -ENOMEM;
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sargs->space_slots = count;
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sargs->total_spaces = 0;
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ret = ioctl(fd, BTRFS_IOC_SPACE_INFO, sargs);
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if (ret < 0) {
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error("cannot get space info with %llu slots: %m",
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count);
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free(sargs);
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return -errno;
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}
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*sargs_ret = sargs;
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return 0;
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}
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static u64 find_max_device_id(struct btrfs_tree_search_args *args, int nr_items)
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{
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struct btrfs_dev_item *dev_item;
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char *buf = btrfs_tree_search_data(args, 0);
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buf += (nr_items - 1) * (sizeof(struct btrfs_ioctl_search_header)
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+ sizeof(struct btrfs_dev_item));
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buf += sizeof(struct btrfs_ioctl_search_header);
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dev_item = (struct btrfs_dev_item *)buf;
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return btrfs_stack_device_id(dev_item);
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}
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static int search_chunk_tree_for_fs_info(int fd,
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struct btrfs_ioctl_fs_info_args *fi_args)
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{
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int ret;
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int max_items;
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u64 start_devid = 1;
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struct btrfs_tree_search_args args;
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struct btrfs_ioctl_search_key *sk;
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fi_args->num_devices = 0;
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max_items = BTRFS_SEARCH_ARGS_BUFSIZE
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/ (sizeof(struct btrfs_ioctl_search_header)
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+ sizeof(struct btrfs_dev_item));
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memset(&args, 0, sizeof(args));
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sk = btrfs_tree_search_sk(&args);
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sk->tree_id = BTRFS_CHUNK_TREE_OBJECTID;
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sk->min_objectid = BTRFS_DEV_ITEMS_OBJECTID;
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sk->min_type = BTRFS_DEV_ITEM_KEY;
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sk->max_objectid = BTRFS_DEV_ITEMS_OBJECTID;
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sk->max_type = BTRFS_DEV_ITEM_KEY;
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sk->min_transid = 0;
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sk->max_transid = (u64)-1;
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sk->nr_items = max_items;
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sk->max_offset = (u64)-1;
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again:
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sk->min_offset = start_devid;
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ret = btrfs_tree_search_ioctl(fd, &args);
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if (ret < 0)
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return -errno;
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fi_args->num_devices += (u64)sk->nr_items;
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if (sk->nr_items == max_items) {
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start_devid = find_max_device_id(&args, sk->nr_items) + 1;
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goto again;
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}
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/* Get the latest max_id to stay consistent with the num_devices */
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if (sk->nr_items == 0)
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/*
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* last tree_search returns an empty buf, use the devid of
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* the last dev_item of the previous tree_search
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*/
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fi_args->max_id = start_devid - 1;
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else
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fi_args->max_id = find_max_device_id(&args, sk->nr_items);
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return 0;
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}
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/*
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* For a given path, fill in the ioctl fs_ and info_ args.
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* If the path is a btrfs mountpoint, fill info for all devices.
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* If the path is a btrfs device, fill in only that device.
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*
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* The path provided must be either on a mounted btrfs fs,
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* or be a mounted btrfs device.
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*
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* Returns 0 on success, or a negative errno.
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*/
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int get_fs_info(const char *path, struct btrfs_ioctl_fs_info_args *fi_args,
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struct btrfs_ioctl_dev_info_args **di_ret)
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{
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int fd = -1;
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int ret = 0;
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int ndevs = 0;
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u64 last_devid = 0;
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int replacing = 0;
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struct btrfs_fs_devices *fs_devices_mnt = NULL;
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struct btrfs_ioctl_dev_info_args *di_args;
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struct btrfs_ioctl_dev_info_args tmp;
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char mp[PATH_MAX];
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memset(fi_args, 0, sizeof(*fi_args));
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if (path_is_block_device(path) == 1) {
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struct btrfs_super_block disk_super;
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/* Ensure it's mounted, then set path to the mountpoint */
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fd = open(path, O_RDONLY);
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if (fd < 0) {
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ret = -errno;
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error("cannot open %s: %m", path);
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goto out;
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}
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ret = check_mounted_where(fd, path, mp, sizeof(mp),
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&fs_devices_mnt, SBREAD_DEFAULT, false);
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if (!ret) {
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ret = -EINVAL;
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goto out;
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}
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if (ret < 0)
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goto out;
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path = mp;
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/* Only fill in this one device */
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fi_args->num_devices = 1;
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ret = btrfs_read_dev_super(fd, &disk_super,
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BTRFS_SUPER_INFO_OFFSET, 0);
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if (ret < 0) {
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ret = -EIO;
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goto out;
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}
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last_devid = btrfs_stack_device_id(&disk_super.dev_item);
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fi_args->max_id = last_devid;
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memcpy(fi_args->fsid, fs_devices_mnt->fsid, BTRFS_FSID_SIZE);
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close(fd);
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}
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/* at this point path must not be for a block device */
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fd = btrfs_open_file_or_dir(path);
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if (fd < 0) {
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ret = fd;
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goto out;
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}
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/* fill in fi_args if not just a single device */
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if (fi_args->num_devices != 1) {
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ret = ioctl(fd, BTRFS_IOC_FS_INFO, fi_args);
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if (ret < 0) {
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ret = -errno;
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goto out;
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}
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/*
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* The fs_args->num_devices does not include seed devices
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*/
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ret = search_chunk_tree_for_fs_info(fd, fi_args);
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if (ret)
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goto out;
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/*
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* search_chunk_tree_for_fs_info() will lacks the devid 0
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* so manual probe for it here.
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*/
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ret = device_get_info(fd, 0, &tmp);
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if (!ret) {
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fi_args->num_devices++;
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ndevs++;
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replacing = 1;
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if (last_devid == 0)
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last_devid++;
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}
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}
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if (!fi_args->num_devices)
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goto out;
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di_args = *di_ret = malloc((fi_args->num_devices) * sizeof(*di_args));
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if (!di_args) {
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ret = -errno;
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goto out;
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}
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if (replacing)
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memcpy(di_args, &tmp, sizeof(tmp));
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for (; last_devid <= fi_args->max_id && ndevs < fi_args->num_devices;
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last_devid++) {
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ret = device_get_info(fd, last_devid, &di_args[ndevs]);
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if (ret == -ENODEV)
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continue;
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if (ret)
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goto out;
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ndevs++;
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}
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/*
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* only when the only dev we wanted to find is not there then
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* let any error be returned
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*/
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if (fi_args->num_devices != 1) {
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BUG_ON(ndevs == 0);
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ret = 0;
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}
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out:
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close(fd);
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return ret;
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}
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int get_fsid_fd(int fd, u8 *fsid)
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{
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int ret;
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struct btrfs_ioctl_fs_info_args args;
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ret = ioctl(fd, BTRFS_IOC_FS_INFO, &args);
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if (ret < 0)
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return -errno;
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memcpy(fsid, args.fsid, BTRFS_FSID_SIZE);
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return 0;
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}
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int get_fsid(const char *path, u8 *fsid, int silent)
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{
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int ret;
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int fd;
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int flags = O_RDONLY;
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struct stat st;
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ret = stat(path, &st);
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if (ret < 0) {
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if (!silent)
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error("failed to stat %s: %m", path);
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return -errno;
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}
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/*
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* Open in non-blocking mode in case that path is a fifo or a special
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* character device where opening gets stuck (but is interruptible).
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*/
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if ((st.st_mode & S_IFMT) == S_IFCHR || (st.st_mode & S_IFMT) == S_IFIFO)
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flags |= O_NONBLOCK;
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fd = open(path, flags);
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if (fd < 0) {
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if (!silent)
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error("failed to open %s: %m", path);
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return -errno;
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}
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ret = get_fsid_fd(fd, fsid);
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close(fd);
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return ret;
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}
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int test_num_disk_vs_raid(u64 metadata_profile, u64 data_profile,
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u64 dev_cnt, int mixed, int ssd)
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{
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u64 allowed;
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u64 profile = metadata_profile | data_profile;
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allowed = btrfs_bg_flags_for_device_num(dev_cnt);
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if (dev_cnt > 1 && profile & BTRFS_BLOCK_GROUP_DUP) {
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warning("DUP is not recommended on filesystem with multiple devices");
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}
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if (metadata_profile & ~allowed) {
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error("unable to create FS with metadata profile %s "
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"(have %llu devices but %d devices are required)",
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btrfs_group_profile_str(metadata_profile), dev_cnt,
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btrfs_bg_type_to_devs_min(metadata_profile));
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return 1;
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}
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if (data_profile & ~allowed) {
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error("ERROR: unable to create FS with data profile %s "
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"(have %llu devices but %d devices are required)",
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btrfs_group_profile_str(data_profile), dev_cnt,
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btrfs_bg_type_to_devs_min(data_profile));
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return 1;
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}
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if (dev_cnt == 3 && profile & BTRFS_BLOCK_GROUP_RAID6) {
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warning("RAID6 is not recommended on filesystem with 3 devices only");
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}
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if (dev_cnt == 2 && profile & BTRFS_BLOCK_GROUP_RAID5) {
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warning("RAID5 is not recommended on filesystem with 2 devices only");
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}
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warning_on(!mixed && (data_profile & BTRFS_BLOCK_GROUP_DUP) && ssd,
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"DUP may not actually lead to 2 copies on the device, see manual page");
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return 0;
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}
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/*
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* This reads a line from the stdin and only returns non-zero if the
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* first whitespace delimited token is a case insensitive match with yes
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* or y.
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*/
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int ask_user(const char *question)
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{
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char buf[30] = {0,};
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char *saveptr = NULL;
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char *answer;
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printf("%s [y/N]: ", question);
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return fgets(buf, sizeof(buf) - 1, stdin) &&
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(answer = strtok_r(buf, " \t\n\r", &saveptr)) &&
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(!strcasecmp(answer, "yes") || !strcasecmp(answer, "y"));
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}
|
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|
|
/*
|
|
* Partial representation of a line in /proc/pid/mountinfo
|
|
*/
|
|
struct mnt_entry {
|
|
const char *root;
|
|
const char *path;
|
|
const char *options1;
|
|
const char *fstype;
|
|
const char *device;
|
|
const char *options2;
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};
|
|
|
|
/*
|
|
* Find first occurrence of up an option string (as "option=") in @options,
|
|
* separated by comma. Return allocated string as "option=value"
|
|
*/
|
|
static char *find_option(const char *options, const char *option)
|
|
{
|
|
char *tmp, *ret;
|
|
|
|
tmp = strstr(options, option);
|
|
if (!tmp)
|
|
return NULL;
|
|
ret = strdup(tmp);
|
|
tmp = ret;
|
|
while (*tmp && *tmp != ',')
|
|
tmp++;
|
|
*tmp = 0;
|
|
return ret;
|
|
}
|
|
|
|
/* Match whitespace separator */
|
|
static bool is_sep(char c)
|
|
{
|
|
return c == ' ' || c == '\t';
|
|
}
|
|
|
|
/* Advance @line skipping over all non-separator chars */
|
|
static void skip_nonsep(char **line)
|
|
{
|
|
while (**line && !is_sep(**line))
|
|
(*line)++;
|
|
}
|
|
|
|
/* Advance @line skipping over all separator chars, setting them to nul char */
|
|
static void skip_sep(char **line)
|
|
{
|
|
while (**line && is_sep(**line)) {
|
|
**line = 0;
|
|
(*line)++;
|
|
}
|
|
}
|
|
|
|
static bool isoctal(char c)
|
|
{
|
|
return '0' <= c && c <= '7';
|
|
}
|
|
|
|
/*
|
|
* Validate complete escape sequence used for mangling special chars in paths,
|
|
* eg. \012 == 10 == 0xa == '\n'.
|
|
* Mandatory format: backslash and 3 octal digits.
|
|
*/
|
|
static bool valid_escape(const char *str)
|
|
{
|
|
if (*str == 0 || *str != '\\')
|
|
return false;
|
|
str++;
|
|
if (*str == 0 || is_sep(*str) || !isoctal(*str))
|
|
return false;
|
|
str++;
|
|
if (*str == 0 || is_sep(*str) || !isoctal(*str))
|
|
return false;
|
|
str++;
|
|
if (*str == 0 || is_sep(*str) || !isoctal(*str))
|
|
return false;
|
|
return true;
|
|
}
|
|
|
|
/*
|
|
* Read a path from @line, with potentially mangled special characters.
|
|
* - the input is changed in-place when unmangling is done
|
|
* - end of path is a space character (a valid space in the path is mangled)
|
|
* - line is advanced to the final separator or nul character
|
|
* - returned path is a valid string terminated by zero or whitespace separator
|
|
*/
|
|
static char *read_path(char **line)
|
|
{
|
|
char *ret = *line;
|
|
char *out = *line;
|
|
|
|
while (**line) {
|
|
if (is_sep(**line))
|
|
break;
|
|
if (valid_escape(*line)) {
|
|
char c;
|
|
|
|
(*line)++;
|
|
c = ((*(*line)++) & 0b111) << 6;
|
|
c |= ((*(*line)++) & 0b111) << 3;
|
|
c |= ((*(*line)++) & 0b111);
|
|
*out++ = c;
|
|
} else {
|
|
*out++ = *(*line)++;
|
|
}
|
|
}
|
|
/*
|
|
* Unmangled characters make the final string shorter, add the null
|
|
* terminator. Otherwise keep the line at the space separator so
|
|
* followup parsing can continue.
|
|
*/
|
|
if (out < *line)
|
|
*out = 0;
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Parse a line from /proc/pid/mountinfo
|
|
* Example:
|
|
|
|
272 265 0:49 /subvol /mnt/path rw,noatime shared:145 - btrfs /dev/sda1 rw,subvolid=5598,subvol=/subvol
|
|
0 1 2 3 4 5 6 7 8 9 10
|
|
|
|
* Fields related to paths and options are parsed, @line is changed in place,
|
|
* separators are replaced by nul char, paths could be unmangled.
|
|
*/
|
|
static void parse_mntinfo_line(char *line, struct mnt_entry *ent)
|
|
{
|
|
/* Skip 0 */
|
|
skip_nonsep(&line);
|
|
skip_sep(&line);
|
|
/* Skip 1 */
|
|
skip_nonsep(&line);
|
|
skip_sep(&line);
|
|
/* Skip 2 */
|
|
skip_nonsep(&line);
|
|
skip_sep(&line);
|
|
/* Read 3 */
|
|
ent->root = read_path(&line);
|
|
skip_sep(&line);
|
|
/* Read 4 */
|
|
ent->path = read_path(&line);
|
|
skip_sep(&line);
|
|
/* Read 5 */
|
|
ent->options1 = line;
|
|
skip_nonsep(&line);
|
|
skip_sep(&line);
|
|
/* Skip 6 */
|
|
skip_nonsep(&line);
|
|
skip_sep(&line);
|
|
/* Skip 7 */
|
|
skip_nonsep(&line);
|
|
skip_sep(&line);
|
|
/* Read 8 */
|
|
ent->fstype = line;
|
|
skip_nonsep(&line);
|
|
skip_sep(&line);
|
|
/* Read 9 */
|
|
ent->device = read_path(&line);
|
|
skip_sep(&line);
|
|
/* Read 10 */
|
|
ent->options2 = line;
|
|
skip_nonsep(&line);
|
|
skip_sep(&line);
|
|
}
|
|
|
|
/*
|
|
* Compare the subvolume passed with the pathname of the directory mounted in
|
|
* btrfs. The pathname inside btrfs is different from getmnt and friends, since
|
|
* it can detect bind mounts to content from the inside of the original mount.
|
|
*
|
|
* Example:
|
|
* # mount -o subvol=/vol /dev/sda2 /mnt
|
|
* # mount --bind /mnt/dir2 /othermnt
|
|
*
|
|
* # mounts
|
|
* ...
|
|
* /dev/sda2 on /mnt type btrfs (ro,relatime,ssd,space_cache,subvolid=256,subvol=/vol)
|
|
* /dev/sda2 on /othermnt type btrfs (ro,relatime,ssd,space_cache,subvolid=256,subvol=/vol)
|
|
*
|
|
* # cat /proc/self/mountinfo
|
|
*
|
|
* 38 30 0:32 /vol /mnt ro,relatime - btrfs /dev/sda2 ro,ssd,space_cache,subvolid=256,subvol=/vol
|
|
* 37 29 0:32 /vol/dir2 /othermnt ro,relatime - btrfs /dev/sda2 ro,ssd,space_cache,subvolid=256,subvol=/vol
|
|
*
|
|
* If we try to find a mount point only using subvol and subvolid from mount
|
|
* options we would get mislead to believe that /othermnt has the same content
|
|
* as /mnt.
|
|
*
|
|
* But, using mountinfo, we have the pathaname _inside_ the filesystem, so we
|
|
* can filter out the mount points with bind mounts which have different content
|
|
* from the original mounts, in this case the mount point with id 37.
|
|
*/
|
|
int find_mount_fsroot(const char *subvol, const char *subvolid, char **mount)
|
|
{
|
|
FILE *mnt;
|
|
char *buf = NULL;
|
|
int bs = 4096;
|
|
int line = 0;
|
|
int ret = 0;
|
|
bool found = false;
|
|
|
|
mnt = fopen("/proc/self/mountinfo", "r");
|
|
if (!mnt)
|
|
return -1;
|
|
|
|
buf = malloc(bs);
|
|
if (!buf) {
|
|
ret = -ENOMEM;
|
|
goto out;
|
|
}
|
|
|
|
do {
|
|
int ch;
|
|
|
|
ch = fgetc(mnt);
|
|
if (ch == -1)
|
|
break;
|
|
|
|
if (ch == '\n') {
|
|
struct mnt_entry ent;
|
|
char *opt;
|
|
const char *value;
|
|
|
|
buf[line] = 0;
|
|
parse_mntinfo_line(buf, &ent);
|
|
|
|
/* Skip unrelated mounts */
|
|
if (strcmp(ent.fstype, "btrfs") != 0)
|
|
goto nextline;
|
|
if (strlen(ent.root) != strlen(subvol))
|
|
goto nextline;
|
|
if (strcmp(ent.root, subvol) != 0)
|
|
goto nextline;
|
|
|
|
/*
|
|
* Match subvolume by id found in mountinfo and
|
|
* requested by the caller
|
|
*/
|
|
opt = find_option(ent.options2, "subvolid=");
|
|
if (!opt)
|
|
goto nextline;
|
|
value = opt + strlen("subvolid=");
|
|
if (strcmp(value, subvolid) != 0) {
|
|
free(opt);
|
|
goto nextline;
|
|
}
|
|
free(opt);
|
|
|
|
/*
|
|
* First match is in most cases the original mount, not
|
|
* a bind mount. In case there are no further bind
|
|
* mounts, return what we found in @mount. Any
|
|
* following mount that matches by path and subvolume
|
|
* id is a bind mount and we return the original mount.
|
|
*/
|
|
if (found)
|
|
goto out;
|
|
found = true;
|
|
*mount = strdup(ent.path);
|
|
ret = 0;
|
|
goto nextline;
|
|
}
|
|
/*
|
|
* Grow buffer if needed, there are 3 paths up to PATH_MAX and
|
|
* mount options are limited by page size. Often the overall
|
|
* line length does not exceed 256.
|
|
*/
|
|
if (line >= bs) {
|
|
char *tmp;
|
|
|
|
bs += 4096;
|
|
tmp = realloc(buf, bs);
|
|
if (!tmp) {
|
|
ret = -ENOMEM;
|
|
goto out;
|
|
}
|
|
buf = tmp;
|
|
}
|
|
buf[line++] = ch;
|
|
continue;
|
|
nextline:
|
|
line = 0;
|
|
} while (1);
|
|
out:
|
|
free(buf);
|
|
fclose(mnt);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* return 0 if a btrfs mount point is found
|
|
* return 1 if a mount point is found but not btrfs
|
|
* return <0 if something goes wrong
|
|
*/
|
|
int find_mount_root(const char *path, char **mount_root)
|
|
{
|
|
FILE *mnttab;
|
|
int fd;
|
|
struct mntent *ent;
|
|
int len;
|
|
int ret = 0;
|
|
int not_btrfs = 1;
|
|
int longest_matchlen = 0;
|
|
char *longest_match = NULL;
|
|
|
|
fd = open(path, O_RDONLY | O_NOATIME);
|
|
if (fd < 0)
|
|
return -errno;
|
|
close(fd);
|
|
|
|
mnttab = setmntent("/proc/self/mounts", "r");
|
|
if (!mnttab)
|
|
return -errno;
|
|
|
|
while ((ent = getmntent(mnttab))) {
|
|
if (path_is_in_dir(ent->mnt_dir, path)) {
|
|
len = strlen(ent->mnt_dir);
|
|
if (longest_matchlen <= len) {
|
|
free(longest_match);
|
|
longest_matchlen = len;
|
|
longest_match = strdup(ent->mnt_dir);
|
|
if (!longest_match) {
|
|
ret = -errno;
|
|
break;
|
|
}
|
|
not_btrfs = strcmp(ent->mnt_type, "btrfs");
|
|
}
|
|
}
|
|
}
|
|
endmntent(mnttab);
|
|
|
|
if (ret)
|
|
return ret;
|
|
if (!longest_match)
|
|
return -ENOENT;
|
|
if (not_btrfs) {
|
|
free(longest_match);
|
|
return 1;
|
|
}
|
|
|
|
ret = 0;
|
|
*mount_root = realpath(longest_match, NULL);
|
|
if (!*mount_root)
|
|
ret = -errno;
|
|
|
|
free(longest_match);
|
|
return ret;
|
|
}
|
|
|
|
int find_next_key(struct btrfs_path *path, struct btrfs_key *key)
|
|
{
|
|
int level;
|
|
|
|
for (level = 0; level < BTRFS_MAX_LEVEL; level++) {
|
|
if (!path->nodes[level])
|
|
break;
|
|
if (path->slots[level] + 1 >=
|
|
btrfs_header_nritems(path->nodes[level]))
|
|
continue;
|
|
if (level == 0)
|
|
btrfs_item_key_to_cpu(path->nodes[level], key,
|
|
path->slots[level] + 1);
|
|
else
|
|
btrfs_node_key_to_cpu(path->nodes[level], key,
|
|
path->slots[level] + 1);
|
|
return 0;
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
const char* btrfs_group_type_str(u64 flag)
|
|
{
|
|
u64 mask = BTRFS_BLOCK_GROUP_TYPE_MASK |
|
|
BTRFS_SPACE_INFO_GLOBAL_RSV;
|
|
|
|
switch (flag & mask) {
|
|
case BTRFS_BLOCK_GROUP_DATA:
|
|
return "Data";
|
|
case BTRFS_BLOCK_GROUP_SYSTEM:
|
|
return "System";
|
|
case BTRFS_BLOCK_GROUP_METADATA:
|
|
return "Metadata";
|
|
case BTRFS_BLOCK_GROUP_DATA|BTRFS_BLOCK_GROUP_METADATA:
|
|
return "Data+Metadata";
|
|
case BTRFS_SPACE_INFO_GLOBAL_RSV:
|
|
return "GlobalReserve";
|
|
default:
|
|
return "unknown";
|
|
}
|
|
}
|
|
|
|
const char* btrfs_group_profile_str(u64 flag)
|
|
{
|
|
int index;
|
|
|
|
flag &= ~(BTRFS_BLOCK_GROUP_TYPE_MASK | BTRFS_BLOCK_GROUP_RESERVED);
|
|
if (flag & ~BTRFS_BLOCK_GROUP_PROFILE_MASK)
|
|
return "UNKNOWN";
|
|
|
|
index = btrfs_bg_flags_to_raid_index(flag);
|
|
return btrfs_raid_array[index].upper_name;
|
|
}
|
|
|
|
u64 div_factor(u64 num, int factor)
|
|
{
|
|
if (factor == 10)
|
|
return num;
|
|
num *= factor;
|
|
num /= 10;
|
|
return num;
|
|
}
|
|
/*
|
|
* Get the length of the string converted from a u64 number.
|
|
*
|
|
* Result is equal to log10(num) + 1, but without the use of math library.
|
|
*/
|
|
int count_digits(u64 num)
|
|
{
|
|
int ret = 0;
|
|
|
|
if (num == 0)
|
|
return 1;
|
|
while (num > 0) {
|
|
ret++;
|
|
num /= 10;
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
const char *subvol_strip_mountpoint(const char *mnt, const char *full_path)
|
|
{
|
|
int len = strlen(mnt);
|
|
if (!len)
|
|
return full_path;
|
|
|
|
if ((strncmp(mnt, full_path, len) != 0) || ((len > 1) && (full_path[len] != '/'))) {
|
|
error("not on mount point: %s", mnt);
|
|
exit(1);
|
|
}
|
|
|
|
if (mnt[len - 1] != '/')
|
|
len += 1;
|
|
|
|
return full_path + len;
|
|
}
|
|
|
|
/* Set the seed manually */
|
|
void init_rand_seed(u64 seed)
|
|
{
|
|
int i;
|
|
|
|
/* only use the last 48 bits */
|
|
for (i = 0; i < 3; i++) {
|
|
rand_seed[i] = (unsigned short)(seed ^ (unsigned short)(-1));
|
|
seed >>= 16;
|
|
}
|
|
rand_seed_initialized = 1;
|
|
}
|
|
|
|
static void __init_seed(void)
|
|
{
|
|
struct timeval tv;
|
|
int ret;
|
|
int fd;
|
|
|
|
if(rand_seed_initialized)
|
|
return;
|
|
/* Use urandom as primary seed source. */
|
|
fd = open("/dev/urandom", O_RDONLY);
|
|
if (fd >= 0) {
|
|
ret = read(fd, rand_seed, sizeof(rand_seed));
|
|
close(fd);
|
|
if (ret < sizeof(rand_seed))
|
|
goto fallback;
|
|
} else {
|
|
fallback:
|
|
/* Use time and pid as fallback seed */
|
|
warning("failed to read /dev/urandom, use time and pid as random seed");
|
|
gettimeofday(&tv, 0);
|
|
rand_seed[0] = getpid() ^ (tv.tv_sec & 0xFFFF);
|
|
rand_seed[1] = getppid() ^ (tv.tv_usec & 0xFFFF);
|
|
rand_seed[2] = (tv.tv_sec ^ tv.tv_usec) >> 16;
|
|
}
|
|
rand_seed_initialized = 1;
|
|
}
|
|
|
|
u32 rand_u32(void)
|
|
{
|
|
__init_seed();
|
|
/*
|
|
* Don't use nrand48, its range is [0,2^31) The highest bit will always
|
|
* be 0. Use jrand48 to include the highest bit.
|
|
*/
|
|
return (u32)jrand48(rand_seed);
|
|
}
|
|
|
|
/* Return random number in range [0, upper) */
|
|
unsigned int rand_range(unsigned int upper)
|
|
{
|
|
__init_seed();
|
|
/*
|
|
* Use the full 48bits to mod, which would be more uniformly
|
|
* distributed
|
|
*/
|
|
return (unsigned int)(jrand48(rand_seed) % upper);
|
|
}
|
|
|
|
int rand_int(void)
|
|
{
|
|
return (int)(rand_u32());
|
|
}
|
|
|
|
u64 rand_u64(void)
|
|
{
|
|
u64 ret = 0;
|
|
|
|
ret += rand_u32();
|
|
ret <<= 32;
|
|
ret += rand_u32();
|
|
return ret;
|
|
}
|
|
|
|
u16 rand_u16(void)
|
|
{
|
|
return (u16)(rand_u32());
|
|
}
|
|
|
|
u8 rand_u8(void)
|
|
{
|
|
return (u8)(rand_u32());
|
|
}
|
|
|
|
/*
|
|
* Parse a boolean value from an environment variable.
|
|
*
|
|
* As long as the environment variable is not set to "0", "n" or "\0",
|
|
* it would return true.
|
|
*/
|
|
bool get_env_bool(const char *env_name)
|
|
{
|
|
char *env_value_str;
|
|
|
|
env_value_str = getenv(env_name);
|
|
if (!env_value_str)
|
|
return false;
|
|
if (env_value_str[0] == '0' || env_value_str[0] == 'n' ||
|
|
env_value_str[0] == 0)
|
|
return false;
|
|
return true;
|
|
}
|
|
|
|
void btrfs_config_init(void)
|
|
{
|
|
bconf.output_format = CMD_FORMAT_TEXT;
|
|
bconf.verbose = BTRFS_BCONF_UNSET;
|
|
INIT_LIST_HEAD(&bconf.params);
|
|
}
|
|
|
|
void bconf_be_verbose(void)
|
|
{
|
|
if (bconf.verbose == BTRFS_BCONF_UNSET)
|
|
bconf.verbose = 1;
|
|
else
|
|
bconf.verbose++;
|
|
}
|
|
|
|
void bconf_be_quiet(void)
|
|
{
|
|
bconf.verbose = BTRFS_BCONF_QUIET;
|
|
}
|
|
|
|
void bconf_add_param(const char *key, const char *value)
|
|
{
|
|
struct config_param *param;
|
|
|
|
param = calloc(1, sizeof(*param));
|
|
if (!param)
|
|
return;
|
|
param->key = strdup(key);
|
|
if (value)
|
|
param->value = strdup(value);
|
|
list_add(¶m->list, &bconf.params);
|
|
}
|
|
|
|
const char *bconf_param_value(const char *key)
|
|
{
|
|
struct config_param *param;
|
|
|
|
list_for_each_entry(param, &bconf.params, list) {
|
|
if (strcmp(key, param->key) == 0)
|
|
return param->value;
|
|
}
|
|
return NULL;
|
|
}
|
|
|
|
void bconf_save_param(const char *str)
|
|
{
|
|
char *tmp;
|
|
|
|
tmp = strchr(str, '=');
|
|
if (!tmp) {
|
|
bconf_add_param(str, NULL);
|
|
printf("Global param: %s\n", str);
|
|
} else {
|
|
*tmp = 0;
|
|
bconf_add_param(str, tmp + 1);
|
|
printf("Global param: %s=%s\n", str, tmp + 1);
|
|
*tmp = '=';
|
|
}
|
|
}
|
|
|
|
void bconf_set_dry_run(void)
|
|
{
|
|
pr_verbose(LOG_INFO, "Dry-run requested\n");
|
|
bconf.dry_run = 1;
|
|
}
|
|
|
|
bool bconf_is_dry_run(void)
|
|
{
|
|
return bconf.dry_run == 1;
|
|
}
|
|
|
|
/* Returns total size of main memory in bytes, -1UL if error. */
|
|
unsigned long total_memory(void)
|
|
{
|
|
struct sysinfo si;
|
|
|
|
if (sysinfo(&si) < 0) {
|
|
error("can't determine memory size");
|
|
return -1UL;
|
|
}
|
|
return si.totalram * si.mem_unit; /* bytes */
|
|
}
|
|
|
|
void print_device_info(struct btrfs_device *device, char *prefix)
|
|
{
|
|
if (prefix)
|
|
printf("%s", prefix);
|
|
printf("Device: id = %llu, name = %s\n",
|
|
device->devid, device->name);
|
|
}
|
|
|
|
void print_all_devices(struct list_head *devices)
|
|
{
|
|
struct btrfs_device *dev;
|
|
|
|
printf("All Devices:\n");
|
|
list_for_each_entry(dev, devices, dev_list)
|
|
print_device_info(dev, "\t");
|
|
printf("\n");
|
|
}
|
|
|
|
static int bit_count(u64 x)
|
|
{
|
|
int ret = 0;
|
|
|
|
while (x) {
|
|
if (x & 1)
|
|
ret++;
|
|
x >>= 1;
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
static char *sprint_profiles(u64 profiles)
|
|
{
|
|
int i;
|
|
int maxlen = 1;
|
|
char *ptr;
|
|
|
|
if (bit_count(profiles) <= 1)
|
|
return NULL;
|
|
|
|
for (i = 0; i < BTRFS_NR_RAID_TYPES; i++)
|
|
maxlen += strlen(btrfs_raid_array[i].lower_name) + 2;
|
|
|
|
ptr = calloc(1, maxlen);
|
|
if (!ptr)
|
|
return NULL;
|
|
|
|
if (profiles & BTRFS_AVAIL_ALLOC_BIT_SINGLE)
|
|
strcat(ptr, btrfs_raid_array[BTRFS_RAID_SINGLE].lower_name);
|
|
|
|
for (i = 0; i < BTRFS_NR_RAID_TYPES; i++) {
|
|
if (!(btrfs_raid_array[i].bg_flag & profiles))
|
|
continue;
|
|
|
|
if (ptr[0])
|
|
strcat(ptr, ", ");
|
|
strcat(ptr, btrfs_raid_array[i].lower_name);
|
|
}
|
|
|
|
return ptr;
|
|
}
|
|
|
|
static int btrfs_get_string_for_multiple_profiles(int fd, char **data_ret,
|
|
char **metadata_ret, char **mixed_ret, char **system_ret,
|
|
char **types_ret)
|
|
{
|
|
int ret;
|
|
int i;
|
|
struct btrfs_ioctl_space_args *sargs;
|
|
u64 data_profiles = 0;
|
|
u64 metadata_profiles = 0;
|
|
u64 system_profiles = 0;
|
|
u64 mixed_profiles = 0;
|
|
const u64 mixed_profile_fl = BTRFS_BLOCK_GROUP_METADATA |
|
|
BTRFS_BLOCK_GROUP_DATA;
|
|
|
|
ret = get_df(fd, &sargs);
|
|
if (ret < 0)
|
|
return -1;
|
|
|
|
for (i = 0; i < sargs->total_spaces; i++) {
|
|
u64 flags = sargs->spaces[i].flags;
|
|
|
|
if (!(flags & BTRFS_BLOCK_GROUP_PROFILE_MASK))
|
|
flags |= BTRFS_AVAIL_ALLOC_BIT_SINGLE;
|
|
|
|
if ((flags & mixed_profile_fl) == mixed_profile_fl)
|
|
mixed_profiles |= flags;
|
|
else if (flags & BTRFS_BLOCK_GROUP_DATA)
|
|
data_profiles |= flags;
|
|
else if (flags & BTRFS_BLOCK_GROUP_METADATA)
|
|
metadata_profiles |= flags;
|
|
else if (flags & BTRFS_BLOCK_GROUP_SYSTEM)
|
|
system_profiles |= flags;
|
|
}
|
|
free(sargs);
|
|
|
|
data_profiles &= BTRFS_EXTENDED_PROFILE_MASK;
|
|
system_profiles &= BTRFS_EXTENDED_PROFILE_MASK;
|
|
mixed_profiles &= BTRFS_EXTENDED_PROFILE_MASK;
|
|
metadata_profiles &= BTRFS_EXTENDED_PROFILE_MASK;
|
|
|
|
*data_ret = sprint_profiles(data_profiles);
|
|
*metadata_ret = sprint_profiles(metadata_profiles);
|
|
*mixed_ret = sprint_profiles(mixed_profiles);
|
|
*system_ret = sprint_profiles(system_profiles);
|
|
|
|
if (types_ret) {
|
|
*types_ret = calloc(1, 64);
|
|
if (!*types_ret)
|
|
goto out;
|
|
if (*data_ret)
|
|
strcat(*types_ret, "data");
|
|
if (*metadata_ret) {
|
|
if ((*types_ret)[0])
|
|
strcat(*types_ret, ", ");
|
|
strcat(*types_ret, "metadata");
|
|
}
|
|
if (*mixed_ret) {
|
|
if ((*types_ret)[0])
|
|
strcat(*types_ret, ", ");
|
|
strcat(*types_ret, "data+metadata");
|
|
}
|
|
if (*system_ret) {
|
|
if ((*types_ret)[0])
|
|
strcat(*types_ret, ", ");
|
|
strcat(*types_ret, "system");
|
|
}
|
|
}
|
|
|
|
out:
|
|
return *data_ret || *metadata_ret || *mixed_ret || *system_ret;
|
|
}
|
|
|
|
/*
|
|
* Return string containing coma separated list of block group types that
|
|
* contain multiple profiles. The return value must be freed by the caller.
|
|
*/
|
|
char *btrfs_test_for_multiple_profiles(int fd)
|
|
{
|
|
char *data = NULL;
|
|
char *metadata = NULL;
|
|
char *system = NULL;
|
|
char *mixed = NULL;
|
|
char *types = NULL;
|
|
|
|
btrfs_get_string_for_multiple_profiles(fd, &data, &metadata, &mixed,
|
|
&system, &types);
|
|
free(data);
|
|
free(metadata);
|
|
free(mixed);
|
|
free(system);
|
|
|
|
return types;
|
|
}
|
|
|
|
int btrfs_warn_multiple_profiles(int fd)
|
|
{
|
|
int ret;
|
|
char *data_prof, *mixed_prof, *metadata_prof, *system_prof;
|
|
|
|
ret = btrfs_get_string_for_multiple_profiles(fd, &data_prof,
|
|
&metadata_prof, &mixed_prof, &system_prof, NULL);
|
|
|
|
if (ret != 1)
|
|
return ret;
|
|
|
|
warning("Multiple block group profiles detected, see 'man btrfs(5)'");
|
|
warning_on(!!data_prof, " Data: %s", data_prof);
|
|
warning_on(!!metadata_prof, " Metadata: %s", metadata_prof);
|
|
warning_on(!!mixed_prof, " Data+Metadata: %s", mixed_prof);
|
|
warning_on(!!system_prof, " System: %s", system_prof);
|
|
|
|
free(data_prof);
|
|
free(metadata_prof);
|
|
free(mixed_prof);
|
|
free(system_prof);
|
|
|
|
return 1;
|
|
}
|
|
|
|
void btrfs_warn_experimental(const char *str)
|
|
{
|
|
#if EXPERIMENTAL
|
|
warning("Experimental build with unstable or unfinished features");
|
|
warning_on(str != NULL, "%s\n", str);
|
|
#endif
|
|
}
|
|
|
|
static const char exclop_def[][16] = {
|
|
[BTRFS_EXCLOP_NONE] = "none",
|
|
[BTRFS_EXCLOP_BALANCE] = "balance",
|
|
[BTRFS_EXCLOP_BALANCE_PAUSED] = "balance paused",
|
|
[BTRFS_EXCLOP_DEV_ADD] = "device add",
|
|
[BTRFS_EXCLOP_DEV_REMOVE] = "device remove",
|
|
[BTRFS_EXCLOP_DEV_REPLACE] = "device replace",
|
|
[BTRFS_EXCLOP_RESIZE] = "resize",
|
|
[BTRFS_EXCLOP_SWAP_ACTIVATE] = "swap activate",
|
|
};
|
|
|
|
/*
|
|
* Read currently running exclusive operation from sysfs. If this is not
|
|
* available, return BTRFS_EXCLOP_UNKNOWN
|
|
*/
|
|
int get_fs_exclop(int fd)
|
|
{
|
|
int sysfs_fd;
|
|
char buf[32];
|
|
int ret;
|
|
int i;
|
|
|
|
sysfs_fd = sysfs_open_fsid_file(fd, "exclusive_operation");
|
|
if (sysfs_fd < 0)
|
|
return BTRFS_EXCLOP_UNKNOWN;
|
|
|
|
memset(buf, 0, sizeof(buf));
|
|
ret = sysfs_read_file(sysfs_fd, buf, sizeof(buf));
|
|
close(sysfs_fd);
|
|
if (ret <= 0)
|
|
return BTRFS_EXCLOP_UNKNOWN;
|
|
|
|
i = strlen(buf) - 1;
|
|
while (i > 0 && isspace(buf[i])) i--;
|
|
if (i > 0)
|
|
buf[i + 1] = 0;
|
|
for (i = 0; i < ARRAY_SIZE(exclop_def); i++) {
|
|
if (strcmp(exclop_def[i], buf) == 0)
|
|
return i;
|
|
}
|
|
|
|
return BTRFS_EXCLOP_UNKNOWN;
|
|
}
|
|
|
|
const char *get_fs_exclop_name(int op)
|
|
{
|
|
if (0 <= op && op <= ARRAY_SIZE(exclop_def))
|
|
return exclop_def[op];
|
|
return "UNKNOWN";
|
|
}
|
|
|
|
/*
|
|
* Check if there's another exclusive operation running and either return error
|
|
* or wait until there's none in case @enqueue is true. The timeout between
|
|
* checks is 1 minute as we get notification on the sysfs file when the
|
|
* operation finishes.
|
|
*
|
|
* Return:
|
|
* 0 - caller can continue, nothing running or the status is not available
|
|
* 1 - another operation running
|
|
* <0 - there was another error
|
|
*/
|
|
int check_running_fs_exclop(int fd, enum exclusive_operation start, bool enqueue)
|
|
{
|
|
int sysfs_fd;
|
|
int exclop;
|
|
int ret;
|
|
|
|
sysfs_fd = sysfs_open_fsid_file(fd, "exclusive_operation");
|
|
if (sysfs_fd < 0) {
|
|
if (sysfs_fd == -ENOENT)
|
|
return 0;
|
|
return sysfs_fd;
|
|
}
|
|
|
|
exclop = get_fs_exclop(fd);
|
|
if (exclop <= 0) {
|
|
ret = 0;
|
|
goto out;
|
|
}
|
|
|
|
/*
|
|
* Some combinations are compatible:
|
|
* - start device add when balance is paused (kernel 5.17)
|
|
*/
|
|
if (start == BTRFS_EXCLOP_DEV_ADD && exclop == BTRFS_EXCLOP_BALANCE_PAUSED) {
|
|
ret = 0;
|
|
goto out;
|
|
}
|
|
|
|
if (!enqueue) {
|
|
error(
|
|
"unable to start %s, another exclusive operation '%s' in progress",
|
|
get_fs_exclop_name(start),
|
|
get_fs_exclop_name(exclop));
|
|
ret = 1;
|
|
goto out;
|
|
} else {
|
|
pr_verbose(LOG_DEFAULT, "Waiting for another exclusive operation '%s' to finish ...",
|
|
get_fs_exclop_name(exclop));
|
|
fflush(stdout);
|
|
}
|
|
|
|
/*
|
|
* The sysfs file descriptor needs to be reopened and all data read
|
|
* before each select().
|
|
*/
|
|
while (exclop > 0) {
|
|
fd_set fds;
|
|
struct timeval tv = { .tv_sec = 60, .tv_usec = 0 };
|
|
char tmp[1024];
|
|
|
|
close(sysfs_fd);
|
|
sysfs_fd = sysfs_open_fsid_file(fd, "exclusive_operation");
|
|
if (sysfs_fd < 0)
|
|
return sysfs_fd;
|
|
FD_ZERO(&fds);
|
|
FD_SET(sysfs_fd, &fds);
|
|
|
|
ret = read(sysfs_fd, tmp, sizeof(tmp));
|
|
ret = select(sysfs_fd + 1, NULL, NULL, &fds, &tv);
|
|
if (ret < 0) {
|
|
ret = -errno;
|
|
break;
|
|
}
|
|
if (ret > 0) {
|
|
close(sysfs_fd);
|
|
sysfs_fd = sysfs_open_fsid_file(fd, "exclusive_operation");
|
|
if (sysfs_fd < 0)
|
|
return sysfs_fd;
|
|
|
|
FD_ZERO(&fds);
|
|
FD_SET(sysfs_fd, &fds);
|
|
|
|
ret = read(sysfs_fd, tmp, sizeof(tmp));
|
|
/*
|
|
* Notified before the timeout, check again before
|
|
* returning. In case there are more operations
|
|
* waiting, we want to reduce the chances to race so
|
|
* reuse the remaining time to randomize the order.
|
|
*/
|
|
tv.tv_sec = (tv.tv_sec % 10) + 1;
|
|
ret = select(sysfs_fd + 1, NULL, NULL, &fds, &tv);
|
|
exclop = get_fs_exclop(fd);
|
|
if (exclop <= 0)
|
|
ret = 0;
|
|
}
|
|
}
|
|
pr_verbose(LOG_DEFAULT, " done\n");
|
|
out:
|
|
close(sysfs_fd);
|
|
|
|
return ret;
|
|
}
|