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-rw-r--r--btrfstune.c553
1 files changed, 553 insertions, 0 deletions
diff --git a/btrfstune.c b/btrfstune.c
new file mode 100644
index 00000000..f731e3d2
--- /dev/null
+++ b/btrfstune.c
@@ -0,0 +1,553 @@
+/*
+ * 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 <getopt.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;
+ int ret;
+
+ 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);
+ ret = btrfs_commit_transaction(trans, root);
+
+ return ret;
+}
+
+static int set_super_incompat_flags(struct btrfs_root *root, u64 flags)
+{
+ struct btrfs_trans_handle *trans;
+ struct btrfs_super_block *disk_super;
+ u64 super_flags;
+ int ret;
+
+ disk_super = root->fs_info->super_copy;
+ super_flags = btrfs_super_incompat_flags(disk_super);
+ super_flags |= flags;
+ trans = btrfs_start_transaction(root, 1);
+ btrfs_set_super_incompat_flags(disk_super, super_flags);
+ ret = btrfs_commit_transaction(trans, root);
+
+ return ret;
+}
+
+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;
+
+ same_fsid = !memcmp_extent_buffer(eb, fs_info->new_fsid,
+ btrfs_header_fsid(), BTRFS_FSID_SIZE);
+ 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;
+
+ 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 (!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;
+
+ 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)
+{
+ struct btrfs_root *tree_root = fs_info->tree_root;
+ u64 flags = btrfs_super_flags(fs_info->super_copy);
+ int ret = 0;
+
+ flags |= BTRFS_SUPER_FLAG_CHANGING_FSID;
+ btrfs_set_super_flags(fs_info->super_copy, flags);
+
+ memcpy(fs_info->super_copy->fsid, fs_info->new_fsid, BTRFS_FSID_SIZE);
+ ret = write_all_supers(tree_root);
+ if (ret < 0)
+ return ret;
+
+ /* also restore new chunk_tree_id into tree_root for restore */
+ write_extent_buffer(tree_root->node, fs_info->new_chunk_tree_uuid,
+ btrfs_header_chunk_tree_uuid(tree_root->node),
+ BTRFS_UUID_SIZE);
+ return write_tree_block(NULL, tree_root, tree_root->node);
+}
+
+static int change_fsid_done(struct btrfs_fs_info *fs_info)
+{
+ u64 flags = btrfs_super_flags(fs_info->super_copy);
+
+ flags &= ~BTRFS_SUPER_FLAG_CHANGING_FSID;
+ btrfs_set_super_flags(fs_info->super_copy, flags);
+
+ return write_all_supers(fs_info->tree_root);
+}
+
+/*
+ * Return 0 for no unfinished fsid change.
+ * Return >0 for unfinished fsid change, and restore unfinished fsid/
+ * chunk_tree_id into fsid_ret/chunk_id_ret.
+ */
+static int check_unfinished_fsid_change(struct btrfs_fs_info *fs_info,
+ uuid_t fsid_ret, uuid_t chunk_id_ret)
+{
+ struct btrfs_root *tree_root = fs_info->tree_root;
+ u64 flags = btrfs_super_flags(fs_info->super_copy);
+
+ if (flags & BTRFS_SUPER_FLAG_CHANGING_FSID) {
+ memcpy(fsid_ret, fs_info->super_copy->fsid, BTRFS_FSID_SIZE);
+ read_extent_buffer(tree_root->node, chunk_id_ret,
+ btrfs_header_chunk_tree_uuid(tree_root->node),
+ BTRFS_UUID_SIZE);
+ return 1;
+ }
+ return 0;
+}
+
+/*
+ * Change fsid of a given fs.
+ *
+ * If new_fsid_str is not given, use a random generated UUID.
+ * Caller should check new_fsid_str is valid
+ */
+static int change_uuid(struct btrfs_fs_info *fs_info, const char *new_fsid_str)
+{
+ uuid_t new_fsid;
+ uuid_t new_chunk_id;
+ uuid_t old_fsid;
+ char uuid_buf[BTRFS_UUID_UNPARSED_SIZE];
+ int ret = 0;
+
+ if (check_unfinished_fsid_change(fs_info, new_fsid, new_chunk_id)) {
+ if (new_fsid_str) {
+ uuid_t tmp;
+
+ uuid_parse(new_fsid_str, tmp);
+ if (memcmp(tmp, new_fsid, BTRFS_FSID_SIZE)) {
+ fprintf(stderr,
+ "ERROR: New fsid %s is not the same with unfinished fsid change\n",
+ new_fsid_str);
+ return -EINVAL;
+ }
+ }
+ } else {
+ if (new_fsid_str)
+ uuid_parse(new_fsid_str, new_fsid);
+ else
+ uuid_generate(new_fsid);
+
+ uuid_generate(new_chunk_id);
+ }
+ fs_info->new_fsid = new_fsid;
+ fs_info->new_chunk_tree_uuid = new_chunk_id;
+
+ memcpy(old_fsid, (const char*)fs_info->fsid, BTRFS_UUID_SIZE);
+ uuid_unparse(old_fsid, uuid_buf);
+ printf("Current fsid: %s\n", uuid_buf);
+
+ uuid_unparse(new_fsid, uuid_buf);
+ printf("New fsid: %s\n", uuid_buf);
+ /* Now we can begin fsid change */
+ printf("Set superblock flag CHANGING_FSID\n");
+ ret = change_fsid_prepare(fs_info);
+ if (ret < 0)
+ goto out;
+
+ /* Change extents first */
+ printf("Change fsid in extents\n");
+ ret = change_extents_uuid(fs_info);
+ if (ret < 0) {
+ fprintf(stderr, "Failed to change UUID of metadata\n");
+ goto out;
+ }
+
+ /* Then devices */
+ printf("Change fsid on devices\n");
+ 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 */
+ 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 */
+ printf("Clear superblock flag CHANGING_FSID\n");
+ ret = change_fsid_done(fs_info);
+ fs_info->new_fsid = NULL;
+ fs_info->new_chunk_tree_uuid = NULL;
+ printf("Fsid change finished\n");
+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-n \t\tenable no-holes feature (more efficient sparse file representation)\n");
+ fprintf(stderr, "\t-f \t\tforce to do dangerous operation, make sure that you are aware of the dangers\n");
+ fprintf(stderr, "\t-u \t\tchange fsid, use a random one\n");
+ fprintf(stderr, "\t-U UUID\t\tchange fsid to UUID\n");
+}
+
+int main(int argc, char *argv[])
+{
+ struct btrfs_root *root;
+ enum btrfs_open_ctree_flags ctree_flags = OPEN_CTREE_WRITES;
+ int success = 0;
+ int total = 0;
+ int seeding_flag = 0;
+ u64 seeding_value = 0;
+ int random_fsid = 0;
+ char *new_fsid_str = NULL;
+ int ret;
+ u64 super_flags = 0;
+
+ optind = 1;
+ while(1) {
+ static const struct option long_options[] = {
+ { "help", no_argument, NULL, GETOPT_VAL_HELP},
+ { NULL, 0, NULL, 0 }
+ };
+ int c = getopt_long(argc, argv, "S:rxfuU:n", long_options, NULL);
+
+ if (c < 0)
+ break;
+ switch(c) {
+ case 'S':
+ seeding_flag = 1;
+ seeding_value = arg_strtou64(optarg);
+ break;
+ case 'r':
+ super_flags |= BTRFS_FEATURE_INCOMPAT_EXTENDED_IREF;
+ break;
+ case 'x':
+ super_flags |= BTRFS_FEATURE_INCOMPAT_SKINNY_METADATA;
+ break;
+ case 'n':
+ super_flags |= BTRFS_FEATURE_INCOMPAT_NO_HOLES;
+ break;
+ case 'f':
+ force = 1;
+ break;
+ case 'U':
+ ctree_flags |= OPEN_CTREE_IGNORE_FSID_MISMATCH;
+ new_fsid_str = optarg;
+ break;
+ case 'u':
+ ctree_flags |= OPEN_CTREE_IGNORE_FSID_MISMATCH;
+ random_fsid = 1;
+ break;
+ case GETOPT_VAL_HELP:
+ default:
+ print_usage();
+ return c != GETOPT_VAL_HELP;
+ }
+ }
+
+ set_argv0(argv);
+ device = argv[optind];
+ if (check_argc_exact(argc - optind, 1)) {
+ print_usage();
+ return 1;
+ }
+
+ if (random_fsid && new_fsid_str) {
+ fprintf(stderr,
+ "ERROR: Random fsid can't be used with specified fsid\n");
+ return 1;
+ }
+ if (!super_flags && !seeding_flag && !(random_fsid || new_fsid_str)) {
+ fprintf(stderr,
+ "ERROR: At least one option should be assigned.\n");
+ print_usage();
+ return 1;
+ }
+
+ if (new_fsid_str) {
+ uuid_t tmp;
+
+ ret = uuid_parse(new_fsid_str, tmp);
+ if (ret < 0) {
+ fprintf(stderr,
+ "ERROR: Could not parse UUID: %s\n",
+ new_fsid_str);
+ return 1;
+ }
+ if (!test_uuid_unique(new_fsid_str)) {
+ fprintf(stderr,
+ "ERROR: Fsid %s is not unique\n",
+ new_fsid_str);
+ 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, ctree_flags);
+
+ 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");
+ ret = 1;
+ goto out;
+ }
+ }
+
+ ret = update_seeding_flag(root, seeding_value);
+ if (!ret)
+ success++;
+ total++;
+ }
+
+ if (super_flags) {
+ ret = set_super_incompat_flags(root, super_flags);
+ if (!ret)
+ success++;
+ total++;
+ }
+
+ if (random_fsid || new_fsid_str) {
+ if (!force) {
+ fprintf(stderr,
+ "Warning: It's highly recommended to run 'btrfs check' before this operation\n");
+ fprintf(stderr,
+ "Also canceling running UUID change progress may cause corruption\n");
+ ret = ask_user("We are going to change UUID, are your sure?");
+ if (!ret) {
+ fprintf(stderr, "UUID change canceled\n");
+ ret = 1;
+ goto out;
+ }
+ }
+ ret = change_uuid(root->fs_info, new_fsid_str);
+ if (!ret)
+ success++;
+ total++;
+ }
+
+ if (success == total) {
+ ret = 0;
+ } else {
+ root->fs_info->readonly = 1;
+ ret = 1;
+ fprintf(stderr, "btrfstune failed\n");
+ }
+out:
+ close_ctree(root);
+ btrfs_close_all_devices();
+
+ return ret;
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-04-23 20:59:02 +0000