btrfs-progs: Remove deprecated btrfs-show-super
[platform/upstream/btrfs-progs.git] / btrfstune.c
index 2c26fe9..eccedf7 100644 (file)
@@ -16,8 +16,6 @@
  * Boston, MA 021110-1307, USA.
  */
 
-#define _XOPEN_SOURCE 500
-#define _GNU_SOURCE 1
 #include <stdio.h>
 #include <stdlib.h>
 #include <sys/types.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 "version.h"
+#include "volumes.h"
+#include "help.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) {
-                       fprintf(stderr, "seeding flag is already set on %s\n",
-                               device);
+                       if (force)
+                               return 0;
+                       else
+                               warning("seeding flag is already set on %s",
+                                               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);
+                       warning("seeding flag is not set on %s", device);
                        return 1;
                }
                super_flags &= ~BTRFS_SUPER_FLAG_SEEDING;
+               warning("seeding flag cleared on %s", device);
        }
 
        trans = btrfs_start_transaction(root, 1);
+       BUG_ON(IS_ERR(trans));
        btrfs_set_super_flags(disk_super, super_flags);
-       btrfs_commit_transaction(trans, root);
+       ret = btrfs_commit_transaction(trans, root);
 
-       return 0;
+       return ret;
 }
 
-static int enable_extrefs_flag(struct btrfs_root *root)
+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 |= BTRFS_FEATURE_INCOMPAT_EXTENDED_IREF;
+       super_flags |= flags;
        trans = btrfs_start_transaction(root, 1);
+       BUG_ON(IS_ERR(trans));
        btrfs_set_super_incompat_flags(disk_super, super_flags);
-       btrfs_commit_transaction(trans, root);
+       ret = btrfs_commit_transaction(trans, root);
 
-       return 0;
+       return ret;
 }
 
-static int enable_skinny_metadata(struct btrfs_root *root)
+static int change_header_uuid(struct btrfs_root *root, struct extent_buffer *eb)
 {
-       struct btrfs_trans_handle *trans;
-       struct btrfs_super_block *disk_super;
-       u64 super_flags;
+       struct btrfs_fs_info *fs_info = root->fs_info;
+       int same_fsid = 1;
+       int same_chunk_tree_uuid = 1;
+       int ret;
 
-       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);
+       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, fs_info, 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;
+
+       btrfs_init_path(&path);
+       /*
+        * 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(fs_info, bytenr, 0);
+               if (IS_ERR(eb)) {
+                       error("failed to read tree block: %llu", bytenr);
+                       ret = PTR_ERR(eb);
+                       goto out;
+               }
+               ret = change_header_uuid(root, eb);
+               free_extent_buffer(eb);
+               if (ret < 0) {
+                       error("failed to change uuid of tree block: %llu",
+                               bytenr);
+                       goto out;
+               }
+next:
+               ret = btrfs_next_item(root, &path);
+               if (ret < 0)
+                       goto out;
+               if (ret > 0) {
+                       ret = 0;
+                       goto out;
+               }
+       }
+
+out:
+       btrfs_release_path(&path);
+       return ret;
+}
+
+static int change_device_uuid(struct btrfs_fs_info *fs_info, struct extent_buffer *eb,
+                             int slot)
+{
+       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, fs_info, 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;
+
+       btrfs_init_path(&path);
+       /* 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(fs_info, 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_release_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(fs_info);
+       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, fs_info, 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);
+}
+
+/*
+ * 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)) {
+                               error(
+               "new fsid %s is not the same with unfinished fsid change",
+                                       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) {
+               error("failed to change UUID of metadata: %d", ret);
+               goto out;
+       }
+
+       /* Then devices */
+       printf("Change fsid on devices\n");
+       ret = change_devices_uuid(fs_info);
+       if (ret < 0) {
+               error("failed to change UUID of devices: %d", ret);
+               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);
+       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\tenable/disable seeding\n");
-       fprintf(stderr, "\t-r \t\tenable extended inode refs\n");
-       fprintf(stderr, "\t-x enable skinny metadata extent refs\n");
+       printf("usage: btrfstune [options] device\n");
+       printf("\t-S value\tpositive value will enable seeding, zero to disable, negative is not allowed\n");
+       printf("\t-r \t\tenable extended inode refs\n");
+       printf("\t-x \t\tenable skinny metadata extent refs\n");
+       printf("\t-n \t\tenable no-holes feature (more efficient sparse file representation)\n");
+       printf("\t-f \t\tforce to do dangerous operation, make sure that you are aware of the dangers\n");
+       printf("\t-u \t\tchange fsid, use a random one\n");
+       printf("\t-U UUID\t\tchange fsid to UUID\n");
 }
 
 int main(int argc, char *argv[])
 {
        struct btrfs_root *root;
+       unsigned ctree_flags = OPEN_CTREE_WRITES;
        int success = 0;
-       int extrefs_flag = 0;
+       int total = 0;
        int seeding_flag = 0;
        u64 seeding_value = 0;
-       int skinny_flag = 0;
+       int random_fsid = 0;
+       char *new_fsid_str = NULL;
        int ret;
+       u64 super_flags = 0;
 
-       optind = 1;
        while(1) {
-               int c = getopt(argc, argv, "S:rx");
+               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) {
@@ -126,72 +410,134 @@ int main(int argc, char *argv[])
                        seeding_value = arg_strtou64(optarg);
                        break;
                case 'r':
-                       extrefs_flag = 1;
+                       super_flags |= BTRFS_FEATURE_INCOMPAT_EXTENDED_IREF;
                        break;
                case 'x':
-                       skinny_flag = 1;
+                       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 1;
+                       return c != GETOPT_VAL_HELP;
                }
        }
 
-       argc = argc - optind;
+       set_argv0(argv);
        device = argv[optind];
-       if (argc != 1) {
+       if (check_argc_exact(argc - optind, 1)) {
                print_usage();
                return 1;
        }
 
-       if (!(seeding_flag + extrefs_flag + skinny_flag)) {
-               fprintf(stderr,
-                       "ERROR: At least one option should be assigned.\n");
+       if (random_fsid && new_fsid_str) {
+               error("random fsid can't be used with specified fsid");
+               return 1;
+       }
+       if (!super_flags && !seeding_flag && !(random_fsid || new_fsid_str)) {
+               error("at least one option should be specified");
                print_usage();
                return 1;
        }
 
+       if (new_fsid_str) {
+               uuid_t tmp;
+
+               ret = uuid_parse(new_fsid_str, tmp);
+               if (ret < 0) {
+                       error("could not parse UUID: %s", new_fsid_str);
+                       return 1;
+               }
+               if (!test_uuid_unique(new_fsid_str)) {
+                       error("fsid %s is not unique", new_fsid_str);
+                       return 1;
+               }
+       }
+
        ret = check_mounted(device);
        if (ret < 0) {
-               fprintf(stderr, "Could not check mount status: %s\n",
+               error("could not check mount status of %s: %s", device,
                        strerror(-ret));
                return 1;
        } else if (ret) {
-               fprintf(stderr, "%s is mounted\n", device);
+               error("%s is mounted", device);
                return 1;
        }
 
-       root = open_ctree(device, 0, OPEN_CTREE_WRITES);
+       root = open_ctree(device, 0, ctree_flags);
 
        if (!root) {
-               fprintf(stderr, "Open ctree failed\n");
+               error("open ctree failed");
                return 1;
        }
 
        if (seeding_flag) {
+               if (!seeding_value && !force) {
+                       warning(
+"this is dangerous, clearing the seeding flag may cause the derived device not to be mountable!");
+                       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 (extrefs_flag) {
-               enable_extrefs_flag(root);
-               success++;
+       if (super_flags) {
+               ret = set_super_incompat_flags(root, super_flags);
+               if (!ret)
+                       success++;
+               total++;
        }
 
-       if (skinny_flag) {
-               enable_skinny_metadata(root);
-               success++;
+       if (random_fsid || new_fsid_str) {
+               if (!force) {
+                       warning(
+       "it's highly recommended to run 'btrfs check' before this operation");
+                       warning(
+       "also canceling running UUID change progress may cause corruption");
+                       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 > 0) {
+       if (success == total) {
                ret = 0;
        } else {
                root->fs_info->readonly = 1;
                ret = 1;
-               fprintf(stderr, "btrfstune failed\n");
+               error("btrfstune failed");
        }
+out:
        close_ctree(root);
+       btrfs_close_all_devices();
 
        return ret;
 }