diff options
| -rw-r--r-- | Documentation/btrfs-rescue.asciidoc | 29 | ||||
| -rw-r--r-- | cmds-rescue.c | 48 | ||||
| -rw-r--r-- | volumes.c | 57 | ||||
| -rw-r--r-- | volumes.h | 1 |
4 files changed, 135 insertions, 0 deletions
diff --git a/Documentation/btrfs-rescue.asciidoc b/Documentation/btrfs-rescue.asciidoc index 24b619c6..815abe3c 100644 --- a/Documentation/btrfs-rescue.asciidoc +++ b/Documentation/btrfs-rescue.asciidoc @@ -73,6 +73,35 @@ the log and the filesystem may be mounted normally again. The keywords to look for are 'open_ctree' which says that it's during mount and function names that contain 'replay', 'recover' or 'log_tree'. +*fix-device-size* <device>:: +fix device size and super block total bytes ++ +This command will fix the following problems, by re-aligning all devices' total +bytes and re-calculating super block total bytes. ++ +1. Newer kernel refuse to mount btrfs caused by mismatch super block total bytes ++ +---- +BTRFS error (device sdb): super_total_bytes 92017859088384 mismatch with fs_devices total_rw_bytes 92017859094528 +---- ++ +2. Noisy kernel warning for newer kernels ++ +---- +WARNING: CPU: 3 PID: 439 at fs/btrfs/ctree.h:1559 btrfs_update_device+0x1c5/0x1d0 [btrfs] +---- ++ +And the corresponding line is the `WARN_ON()` line below: ++ +---- +{ + BUILD_BUG_ON(sizeof(u64) != + sizeof(((struct btrfs_dev_item *)0))->total_bytes); + WARN_ON(!IS_ALIGNED(val, eb->fs_info->sectorsize)); + btrfs_set_64(eb, s, offsetof(struct btrfs_dev_item, total_bytes), val); +} +---- + EXIT STATUS ----------- *btrfs rescue* returns a zero exit status if it succeeds. Non zero is diff --git a/cmds-rescue.c b/cmds-rescue.c index 4bc798d2..c40088ad 100644 --- a/cmds-rescue.c +++ b/cmds-rescue.c @@ -20,6 +20,7 @@ #include <getopt.h> #include "ctree.h" +#include "volumes.h" #include "transaction.h" #include "disk-io.h" #include "commands.h" @@ -202,6 +203,51 @@ out: return !!ret; } +static const char * const cmd_rescue_fix_device_size_usage[] = { + "btrfs rescue fix-device-size <device>", + "Re-align device and super block sizes. Usable if newer kernel refuse to mount it due to mismatch super size", + "", + NULL +}; + +static int cmd_rescue_fix_device_size(int argc, char **argv) +{ + struct btrfs_fs_info *fs_info; + char *devname; + int ret; + + clean_args_no_options(argc, argv, cmd_rescue_fix_device_size_usage); + + if (check_argc_exact(argc, 2)) + usage(cmd_rescue_fix_device_size_usage); + + devname = argv[optind]; + ret = check_mounted(devname); + if (ret < 0) { + error("could not check mount status: %s", strerror(-ret)); + goto out; + } else if (ret) { + error("%s is currently mounted", devname); + ret = -EBUSY; + goto out; + } + + fs_info = open_ctree_fs_info(devname, 0, 0, 0, OPEN_CTREE_WRITES | + OPEN_CTREE_PARTIAL); + if (!fs_info) { + error("could not open btrfs"); + ret = -EIO; + goto out; + } + + ret = btrfs_fix_device_and_super_size(fs_info); + if (ret > 0) + ret = 0; + close_ctree(fs_info->tree_root); +out: + return !!ret; +} + static const char rescue_cmd_group_info[] = "toolbox for specific rescue operations"; @@ -212,6 +258,8 @@ const struct cmd_group rescue_cmd_group = { { "super-recover", cmd_rescue_super_recover, cmd_rescue_super_recover_usage, NULL, 0}, { "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}, NULL_CMD_STRUCT } }; @@ -2477,3 +2477,60 @@ int btrfs_fix_super_size(struct btrfs_fs_info *fs_info) old_bytes, total_bytes); return 1; } + +/* + * Return 0 if all devices and super block sizes are good + * Return >0 if any device/super size problem was found, but fixed + * Return <0 if something wrong happened during fixing + */ +int btrfs_fix_device_and_super_size(struct btrfs_fs_info *fs_info) +{ + struct btrfs_device *device; + struct list_head *dev_list = &fs_info->fs_devices->devices; + bool have_bad_value = false; + int ret; + + /* Seed device is not supported yet */ + if (fs_info->fs_devices->seed) { + error("fixing device size with seed device is not supported yet"); + return -EOPNOTSUPP; + } + + /* All devices must be set up before repairing */ + if (list_empty(dev_list)) { + error("no device found"); + return -ENODEV; + } + list_for_each_entry(device, dev_list, dev_list) { + if (device->fd == -1 || !device->writeable) { + error("devid %llu is missing or not writeable", + device->devid); + error( + "fixing device size needs all device(s) to be present and writeable"); + return -ENODEV; + } + } + + /* Repair total_bytes of each device */ + list_for_each_entry(device, dev_list, dev_list) { + ret = btrfs_fix_device_size(fs_info, device); + if (ret < 0) + return ret; + if (ret > 0) + have_bad_value = true; + } + + /* Repair super total_byte */ + ret = btrfs_fix_super_size(fs_info); + if (ret > 0) + have_bad_value = true; + if (have_bad_value) { + printf( + "Fixed unaligned/mismatched total_bytes for super block and device items\n"); + ret = 1; + } else { + printf("No device size related problem found\n"); + ret = 0; + } + return ret; +} @@ -248,4 +248,5 @@ u64 btrfs_stripe_length(struct btrfs_fs_info *fs_info, int btrfs_fix_device_size(struct btrfs_fs_info *fs_info, struct btrfs_device *device); int btrfs_fix_super_size(struct btrfs_fs_info *fs_info); +int btrfs_fix_device_and_super_size(struct btrfs_fs_info *fs_info); #endif |