Provide an offline tool to disable quota. For kernel which skip_balance doesn't work, there is no way to disable quota on huge fs with balance, as quota will cause balance to hang for a long long time for each tree block switch.
So add an offline rescue tool to disable quota. Reported-by: Dan Merillat <dan.meril...@gmail.com> Signed-off-by: Qu Wenruo <w...@suse.com> --- This can patch can be fetched from github repo: https://github.com/adam900710/btrfs-progs/tree/quota_disable --- Documentation/btrfs-rescue.asciidoc | 6 +++ cmds-rescue.c | 80 +++++++++++++++++++++++++++++ 2 files changed, 86 insertions(+) diff --git a/Documentation/btrfs-rescue.asciidoc b/Documentation/btrfs-rescue.asciidoc index f94a0ff2b45e..fb088c1a768a 100644 --- a/Documentation/btrfs-rescue.asciidoc +++ b/Documentation/btrfs-rescue.asciidoc @@ -31,6 +31,12 @@ help. NOTE: Since *chunk-recover* will scan the whole device, it will be *VERY* slow especially executed on a large device. +*disable-quota* <device>:: +disable quota offline ++ +Acts as a fallback method to disable quota for case where mount hangs due to +balance and quota. + *fix-device-size* <device>:: fix device size and super block total bytes values that are do not match + diff --git a/cmds-rescue.c b/cmds-rescue.c index 38c4ab9b2ef6..c7cd92427e9d 100644 --- a/cmds-rescue.c +++ b/cmds-rescue.c @@ -250,6 +250,84 @@ out: return !!ret; } +static const char * const cmd_rescue_disable_quota_usage[] = { + "btrfs rescue disable-quota <device>", + "Disable quota, especially useful for balance mount hang when quota enabled", + "", + NULL +}; + +static int cmd_rescue_disable_quota(int argc, char **argv) +{ + struct btrfs_trans_handle *trans; + struct btrfs_fs_info *fs_info; + struct btrfs_path path; + struct btrfs_root *root; + struct btrfs_qgroup_status_item *qi; + struct btrfs_key key; + char *devname; + int ret; + + clean_args_no_options(argc, argv, cmd_rescue_disable_quota_usage); + if (check_argc_exact(argc, 2)) + usage(cmd_rescue_disable_quota_usage); + + devname = argv[optind]; + ret = check_mounted(devname); + if (ret < 0) { + error("could not check mount status: %s", strerror(-ret)); + return !!ret; + } else if (ret) { + error("%s is currently mounted", devname); + return !!ret; + } + fs_info = open_ctree_fs_info(devname, 0, 0, 0, OPEN_CTREE_WRITES); + if (!fs_info) { + error("could not open btrfs"); + ret = -EIO; + return !!ret; + } + root = fs_info->quota_root; + if (!root) { + printf("Quota is not enabled, no need to modify the fs\n"); + goto close; + } + btrfs_init_path(&path); + trans = btrfs_start_transaction(root, 1); + if (IS_ERR(trans)) { + ret = PTR_ERR(trans); + error("failed to start transaction: %s", strerror(-ret)); + goto close; + } + key.objectid = 0; + key.type = BTRFS_QGROUP_STATUS_KEY; + key.offset = 0; + ret = btrfs_search_slot(trans, root, &key, &path, 0, 1); + if (ret < 0) { + error("failed to search tree: %s", strerror(-ret)); + goto close; + } + if (ret > 0) { + printf( + "qgroup status item not found, not need to modify the fs"); + ret = 0; + goto release; + } + qi = btrfs_item_ptr(path.nodes[0], path.slots[0], + struct btrfs_qgroup_status_item); + btrfs_set_qgroup_status_flags(path.nodes[0], qi, + BTRFS_QGROUP_STATUS_FLAG_INCONSISTENT); + btrfs_mark_buffer_dirty(path.nodes[0]); + ret = btrfs_commit_transaction(trans, root); + if (ret < 0) + error("failed to commit transaction: %s", strerror(-ret)); +release: + btrfs_release_path(&path); +close: + close_ctree(fs_info->tree_root); + return !!ret; +} + static const char rescue_cmd_group_info[] = "toolbox for specific rescue operations"; @@ -262,6 +340,8 @@ const struct cmd_group rescue_cmd_group = { { "zero-log", cmd_rescue_zero_log, cmd_rescue_zero_log_usage, NULL, 0}, { "fix-device-size", cmd_rescue_fix_device_size, cmd_rescue_fix_device_size_usage, NULL, 0}, + { "disable-quota", cmd_rescue_disable_quota, + cmd_rescue_disable_quota_usage, NULL, 0}, NULL_CMD_STRUCT } }; -- 2.18.0
