btrfs-progs/btrfstune.c

478 lines
11 KiB
C

/*
* Copyright (C) 2008 Oracle. All rights reserved.
*
* 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 <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <dirent.h>
#include <uuid/uuid.h>
#include "kerncompat.h"
#include "ctree.h"
#include "disk-io.h"
#include "transaction.h"
#include "utils.h"
#include "volumes.h"
static char *device;
static int force = 0;
static int update_seeding_flag(struct btrfs_root *root, int set_flag)
{
struct btrfs_trans_handle *trans;
struct btrfs_super_block *disk_super;
u64 super_flags;
disk_super = root->fs_info->super_copy;
super_flags = btrfs_super_flags(disk_super);
if (set_flag) {
if (super_flags & BTRFS_SUPER_FLAG_SEEDING) {
if (force)
return 0;
else
fprintf(stderr, "seeding flag is already set on %s\n", device);
return 1;
}
super_flags |= BTRFS_SUPER_FLAG_SEEDING;
} else {
if (!(super_flags & BTRFS_SUPER_FLAG_SEEDING)) {
fprintf(stderr, "seeding flag is not set on %s\n",
device);
return 1;
}
super_flags &= ~BTRFS_SUPER_FLAG_SEEDING;
fprintf(stderr, "Warning: Seeding flag cleared.\n");
}
trans = btrfs_start_transaction(root, 1);
btrfs_set_super_flags(disk_super, super_flags);
btrfs_commit_transaction(trans, root);
return 0;
}
static int enable_extrefs_flag(struct btrfs_root *root)
{
struct btrfs_trans_handle *trans;
struct btrfs_super_block *disk_super;
u64 super_flags;
disk_super = root->fs_info->super_copy;
super_flags = btrfs_super_incompat_flags(disk_super);
super_flags |= BTRFS_FEATURE_INCOMPAT_EXTENDED_IREF;
trans = btrfs_start_transaction(root, 1);
btrfs_set_super_incompat_flags(disk_super, super_flags);
btrfs_commit_transaction(trans, root);
return 0;
}
static int enable_skinny_metadata(struct btrfs_root *root)
{
struct btrfs_trans_handle *trans;
struct btrfs_super_block *disk_super;
u64 super_flags;
disk_super = root->fs_info->super_copy;
super_flags = btrfs_super_incompat_flags(disk_super);
super_flags |= BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA;
trans = btrfs_start_transaction(root, 1);
btrfs_set_super_incompat_flags(disk_super, super_flags);
btrfs_commit_transaction(trans, root);
return 0;
}
static int change_header_uuid(struct btrfs_root *root, struct extent_buffer *eb)
{
struct btrfs_fs_info *fs_info = root->fs_info;
int same_fsid = 1;
int same_chunk_tree_uuid = 1;
int ret;
/* Check for whether we need to change fs/chunk id */
if (!fs_info->new_fsid && !fs_info->new_chunk_tree_uuid)
return 0;
if (fs_info->new_fsid)
same_fsid = !memcmp_extent_buffer(eb, fs_info->new_fsid,
btrfs_header_fsid(), BTRFS_FSID_SIZE);
if (fs_info->new_chunk_tree_uuid)
same_chunk_tree_uuid =
!memcmp_extent_buffer(eb, fs_info->new_chunk_tree_uuid,
btrfs_header_chunk_tree_uuid(eb),
BTRFS_UUID_SIZE);
if (same_fsid && same_chunk_tree_uuid)
return 0;
if (!same_fsid)
write_extent_buffer(eb, fs_info->new_fsid, btrfs_header_fsid(),
BTRFS_FSID_SIZE);
if (!same_chunk_tree_uuid)
write_extent_buffer(eb, fs_info->new_chunk_tree_uuid,
btrfs_header_chunk_tree_uuid(eb),
BTRFS_UUID_SIZE);
ret = write_tree_block(NULL, root, eb);
return ret;
}
static int change_extents_uuid(struct btrfs_fs_info *fs_info)
{
struct btrfs_root *root = fs_info->extent_root;
struct btrfs_path *path;
struct btrfs_key key = {0, 0, 0};
int ret = 0;
if (!fs_info->new_fsid && !fs_info->new_chunk_tree_uuid)
return 0;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
/*
* Here we don't use transaction as it will takes a lot of reserve
* space, and that will make a near-full btrfs unable to change uuid
*/
ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
if (ret < 0)
goto out;
while (1) {
struct btrfs_extent_item *ei;
struct extent_buffer *eb;
u64 flags;
u64 bytenr;
btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
if (key.type != BTRFS_EXTENT_ITEM_KEY &&
key.type != BTRFS_METADATA_ITEM_KEY)
goto next;
ei = btrfs_item_ptr(path->nodes[0], path->slots[0],
struct btrfs_extent_item);
flags = btrfs_extent_flags(path->nodes[0], ei);
if (!(flags & BTRFS_EXTENT_FLAG_TREE_BLOCK))
goto next;
bytenr = key.objectid;
eb = read_tree_block(root, bytenr, root->nodesize, 0);
if (IS_ERR(eb)) {
fprintf(stderr, "Failed to read tree block: %llu\n",
bytenr);
ret = PTR_ERR(eb);
goto out;
}
ret = change_header_uuid(root, eb);
free_extent_buffer(eb);
if (ret < 0) {
fprintf(stderr, "Failed to change uuid of tree block: %llu\n",
bytenr);
goto out;
}
next:
ret = btrfs_next_item(root, path);
if (ret < 0)
goto out;
if (ret > 0) {
ret = 0;
goto out;
}
}
out:
btrfs_free_path(path);
return ret;
}
static int change_device_uuid(struct btrfs_root *root, struct extent_buffer *eb,
int slot)
{
struct btrfs_fs_info *fs_info = root->fs_info;
struct btrfs_dev_item *di;
int ret = 0;
di = btrfs_item_ptr(eb, slot, struct btrfs_dev_item);
if (fs_info->new_fsid) {
if (!memcmp_extent_buffer(eb, fs_info->new_fsid,
(unsigned long)btrfs_device_fsid(di),
BTRFS_FSID_SIZE))
return ret;
write_extent_buffer(eb, fs_info->new_fsid,
(unsigned long)btrfs_device_fsid(di),
BTRFS_FSID_SIZE);
ret = write_tree_block(NULL, root, eb);
}
return ret;
}
static int change_devices_uuid(struct btrfs_fs_info *fs_info)
{
struct btrfs_root *root = fs_info->chunk_root;
struct btrfs_path *path;
struct btrfs_key key = {0, 0, 0};
int ret = 0;
/*
* Unlike change_extents_uuid, we only need to change fsid in dev_item
*/
if (!fs_info->new_fsid)
return 0;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
/* No transaction again */
ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
if (ret < 0)
goto out;
while (1) {
btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
if (key.type != BTRFS_DEV_ITEM_KEY ||
key.objectid != BTRFS_DEV_ITEMS_OBJECTID)
goto next;
ret = change_device_uuid(root, path->nodes[0], path->slots[0]);
if (ret < 0)
goto out;
next:
ret = btrfs_next_item(root, path);
if (ret < 0)
goto out;
if (ret > 0) {
ret = 0;
goto out;
}
}
out:
btrfs_free_path(path);
return ret;
}
static int change_fsid_prepare(struct btrfs_fs_info *fs_info)
{
u64 flags = btrfs_super_flags(fs_info->super_copy);
if (!fs_info->new_fsid && !fs_info->new_chunk_tree_uuid)
return 0;
if (fs_info->new_fsid)
flags |= BTRFS_SUPER_FLAG_CHANGING_FSID;
btrfs_set_super_flags(fs_info->super_copy, flags);
return write_all_supers(fs_info->tree_root);
}
static int change_fsid_done(struct btrfs_fs_info *fs_info)
{
u64 flags = btrfs_super_flags(fs_info->super_copy);
if (!fs_info->new_fsid && !fs_info->new_chunk_tree_uuid)
return 0;
if (fs_info->new_fsid)
flags &= ~BTRFS_SUPER_FLAG_CHANGING_FSID;
btrfs_set_super_flags(fs_info->super_copy, flags);
return write_all_supers(fs_info->tree_root);
}
static int change_uuid(struct btrfs_fs_info *fs_info, const char *new_fsid,
const char *new_chunk_uuid)
{
int ret = 0;
/* caller should do extra check on passed uuid */
if (new_fsid) {
/* allocated mem will be freed at close_ctree() */
fs_info->new_fsid = malloc(BTRFS_FSID_SIZE);
if (!fs_info->new_fsid) {
ret = -ENOMEM;
goto out;
}
ret = uuid_parse(new_fsid, fs_info->new_fsid);
if (ret < 0)
goto out;
}
if (new_chunk_uuid) {
/* allocated mem will be freed at close_ctree() */
fs_info->new_chunk_tree_uuid = malloc(BTRFS_UUID_SIZE);
if (!fs_info->new_chunk_tree_uuid) {
ret = -ENOMEM;
goto out;
}
ret = uuid_parse(new_chunk_uuid, fs_info->new_chunk_tree_uuid);
if (ret < 0)
goto out;
}
/* Now we can begin fsid change */
ret = change_fsid_prepare(fs_info);
if (ret < 0)
goto out;
/* Change extents first */
ret = change_extents_uuid(fs_info);
if (ret < 0) {
fprintf(stderr, "Failed to change UUID of metadata\n");
goto out;
}
/* Then devices */
ret = change_devices_uuid(fs_info);
if (ret < 0) {
fprintf(stderr, "Failed to change UUID of devices\n");
goto out;
}
/* Last, change fsid in super, only fsid change needs this */
if (new_fsid) {
memcpy(fs_info->fs_devices->fsid, fs_info->new_fsid,
BTRFS_FSID_SIZE);
memcpy(fs_info->super_copy->fsid, fs_info->new_fsid,
BTRFS_FSID_SIZE);
ret = write_all_supers(fs_info->tree_root);
if (ret < 0)
goto out;
}
/* Now fsid change is done */
ret = change_fsid_done(fs_info);
out:
return ret;
}
static void print_usage(void)
{
fprintf(stderr, "usage: btrfstune [options] device\n");
fprintf(stderr, "\t-S value\tpositive value will enable seeding, zero to disable, negative is not allowed\n");
fprintf(stderr, "\t-r \t\tenable extended inode refs\n");
fprintf(stderr, "\t-x \t\tenable skinny metadata extent refs\n");
fprintf(stderr, "\t-f \t\tforce to set or clear flags, make sure that you are aware of the dangers\n");
}
int main(int argc, char *argv[])
{
struct btrfs_root *root;
int success = 0;
int total = 0;
int extrefs_flag = 0;
int seeding_flag = 0;
u64 seeding_value = 0;
int skinny_flag = 0;
int ret;
optind = 1;
while(1) {
int c = getopt(argc, argv, "S:rxf");
if (c < 0)
break;
switch(c) {
case 'S':
seeding_flag = 1;
seeding_value = arg_strtou64(optarg);
break;
case 'r':
extrefs_flag = 1;
break;
case 'x':
skinny_flag = 1;
break;
case 'f':
force = 1;
break;
default:
print_usage();
return 1;
}
}
set_argv0(argv);
argc = argc - optind;
device = argv[optind];
if (check_argc_exact(argc, 1)) {
print_usage();
return 1;
}
if (!(seeding_flag + extrefs_flag + skinny_flag)) {
fprintf(stderr,
"ERROR: At least one option should be assigned.\n");
print_usage();
return 1;
}
ret = check_mounted(device);
if (ret < 0) {
fprintf(stderr, "Could not check mount status: %s\n",
strerror(-ret));
return 1;
} else if (ret) {
fprintf(stderr, "%s is mounted\n", device);
return 1;
}
root = open_ctree(device, 0, OPEN_CTREE_WRITES);
if (!root) {
fprintf(stderr, "Open ctree failed\n");
return 1;
}
if (seeding_flag) {
if (!seeding_value && !force) {
fprintf(stderr, "Warning: This is dangerous, clearing the seeding flag may cause the derived device not to be mountable!\n");
ret = ask_user("We are going to clear the seeding flag, are you sure?");
if (!ret) {
fprintf(stderr, "Clear seeding flag canceled\n");
return 1;
}
}
ret = update_seeding_flag(root, seeding_value);
if (!ret)
success++;
total++;
}
if (extrefs_flag) {
enable_extrefs_flag(root);
success++;
total++;
}
if (skinny_flag) {
enable_skinny_metadata(root);
success++;
total++;
}
if (success == total) {
ret = 0;
} else {
root->fs_info->readonly = 1;
ret = 1;
fprintf(stderr, "btrfstune failed\n");
}
close_ctree(root);
return ret;
}