Btrfs-progs superblock checksum check is somewhat too restricted for super-recover, since current btrfs-progs will only read the 1st superblock and if you need super-recover the 1st superblock is possibly already damaged.
The fix is introducing super_recover parameter for btrfs_read_dev_super() and callers to allow scan backup superblocks if needed. Signed-off-by: Qu Wenruo <quwen...@cn.fujitsu.com> --- btrfs-find-root.c | 4 ++-- chunk-recover.c | 6 +++--- cmds-filesystem.c | 2 +- disk-io.c | 17 ++++++++++------- disk-io.h | 5 +++-- super-recover.c | 2 +- utils.c | 11 ++++++----- volumes.c | 4 ++-- volumes.h | 2 +- 9 files changed, 29 insertions(+), 24 deletions(-) diff --git a/btrfs-find-root.c b/btrfs-find-root.c index 25d79f1..e31a9b5 100644 --- a/btrfs-find-root.c +++ b/btrfs-find-root.c @@ -82,7 +82,7 @@ static struct btrfs_root *open_ctree_broken(int fd, const char *device) return NULL; } - ret = btrfs_scan_fs_devices(fd, device, &fs_devices, 0, 1); + ret = btrfs_scan_fs_devices(fd, device, &fs_devices, 0, 1, 1); if (ret) goto out; @@ -94,7 +94,7 @@ static struct btrfs_root *open_ctree_broken(int fd, const char *device) disk_super = fs_info->super_copy; ret = btrfs_read_dev_super(fs_devices->latest_bdev, - disk_super, fs_info->super_bytenr); + disk_super, fs_info->super_bytenr, 1); if (ret) { printk("No valid btrfs found\n"); goto out_devices; diff --git a/chunk-recover.c b/chunk-recover.c index 613d715..9baedd7 100644 --- a/chunk-recover.c +++ b/chunk-recover.c @@ -1283,7 +1283,7 @@ open_ctree_with_broken_chunk(struct recover_control *rc) disk_super = fs_info->super_copy; ret = btrfs_read_dev_super(fs_info->fs_devices->latest_bdev, - disk_super, fs_info->super_bytenr); + disk_super, fs_info->super_bytenr, 1); if (ret) { fprintf(stderr, "No valid btrfs found\n"); goto out_devices; @@ -1349,7 +1349,7 @@ static int recover_prepare(struct recover_control *rc, char *path) goto fail_close_fd; } - ret = btrfs_read_dev_super(fd, sb, BTRFS_SUPER_INFO_OFFSET); + ret = btrfs_read_dev_super(fd, sb, BTRFS_SUPER_INFO_OFFSET, 1); if (ret) { fprintf(stderr, "read super block error\n"); goto fail_free_sb; @@ -1368,7 +1368,7 @@ static int recover_prepare(struct recover_control *rc, char *path) goto fail_free_sb; } - ret = btrfs_scan_fs_devices(fd, path, &fs_devices, 0, 1); + ret = btrfs_scan_fs_devices(fd, path, &fs_devices, 0, 1, 1); if (ret) goto fail_free_sb; diff --git a/cmds-filesystem.c b/cmds-filesystem.c index 306f715..d2e46dc 100644 --- a/cmds-filesystem.c +++ b/cmds-filesystem.c @@ -513,7 +513,7 @@ static int dev_to_fsid(char *dev, __u8 *fsid) disk_super = (struct btrfs_super_block *)buf; ret = btrfs_read_dev_super(fd, disk_super, - BTRFS_SUPER_INFO_OFFSET); + BTRFS_SUPER_INFO_OFFSET, 0); if (ret) goto out; diff --git a/disk-io.c b/disk-io.c index e447af8..1bd9fae 100644 --- a/disk-io.c +++ b/disk-io.c @@ -980,7 +980,7 @@ void btrfs_cleanup_all_caches(struct btrfs_fs_info *fs_info) int btrfs_scan_fs_devices(int fd, const char *path, struct btrfs_fs_devices **fs_devices, - u64 sb_bytenr, int run_ioctl) + u64 sb_bytenr, int run_ioctl, int super_recover) { u64 total_devs; int ret; @@ -988,7 +988,7 @@ int btrfs_scan_fs_devices(int fd, const char *path, sb_bytenr = BTRFS_SUPER_INFO_OFFSET; ret = btrfs_scan_one_device(fd, path, fs_devices, - &total_devs, sb_bytenr); + &total_devs, sb_bytenr, super_recover); if (ret) { fprintf(stderr, "No valid Btrfs found on %s\n", path); return ret; @@ -1076,7 +1076,8 @@ static struct btrfs_fs_info *__open_ctree_fd(int fp, const char *path, fs_info->on_restoring = 1; ret = btrfs_scan_fs_devices(fp, path, &fs_devices, sb_bytenr, - !(flags & OPEN_CTREE_RECOVER_SUPER)); + !(flags & OPEN_CTREE_RECOVER_SUPER), + (flags & OPEN_CTREE_RECOVER_SUPER)); if (ret) goto out; @@ -1096,9 +1097,9 @@ static struct btrfs_fs_info *__open_ctree_fd(int fp, const char *path, disk_super = fs_info->super_copy; if (!(flags & OPEN_CTREE_RECOVER_SUPER)) ret = btrfs_read_dev_super(fs_devices->latest_bdev, - disk_super, sb_bytenr); + disk_super, sb_bytenr, 1); else - ret = btrfs_read_dev_super(fp, disk_super, sb_bytenr); + ret = btrfs_read_dev_super(fp, disk_super, sb_bytenr, 0); if (ret) { printk("No valid btrfs found\n"); goto out_devices; @@ -1182,7 +1183,8 @@ struct btrfs_root *open_ctree_fd(int fp, const char *path, u64 sb_bytenr, return info->fs_root; } -int btrfs_read_dev_super(int fd, struct btrfs_super_block *sb, u64 sb_bytenr) +int btrfs_read_dev_super(int fd, struct btrfs_super_block *sb, u64 sb_bytenr, + int recover_super) { u8 fsid[BTRFS_FSID_SIZE]; int fsid_is_initialized = 0; @@ -1190,6 +1192,7 @@ int btrfs_read_dev_super(int fd, struct btrfs_super_block *sb, u64 sb_bytenr) struct btrfs_super_block *buf = (struct btrfs_super_block *) data; int i; int ret; + int max_super = recover_super ? BTRFS_SUPER_MIRROR_MAX : 1; u64 transid = 0; u64 bytenr; u32 crc; @@ -1215,7 +1218,7 @@ int btrfs_read_dev_super(int fd, struct btrfs_super_block *sb, u64 sb_bytenr) * later supers, using BTRFS_SUPER_MIRROR_MAX instead */ - for (i = 0; i < 1; i++) { + for (i = 0; i < max_super; i++) { bytenr = btrfs_sb_offset(i); ret = pread64(fd, data, sizeof(data), bytenr); if (ret < sizeof(data)) diff --git a/disk-io.h b/disk-io.h index 941a3da..13d4420 100644 --- a/disk-io.h +++ b/disk-io.h @@ -68,7 +68,7 @@ void btrfs_release_all_roots(struct btrfs_fs_info *fs_info); void btrfs_cleanup_all_caches(struct btrfs_fs_info *fs_info); int btrfs_scan_fs_devices(int fd, const char *path, struct btrfs_fs_devices **fs_devices, u64 sb_bytenr, - int run_ioctl); + int run_ioctl, int super_recover); int btrfs_setup_chunk_tree_and_device_map(struct btrfs_fs_info *fs_info); struct btrfs_root *open_ctree(const char *filename, u64 sb_bytenr, @@ -82,7 +82,8 @@ int close_ctree(struct btrfs_root *root); int write_all_supers(struct btrfs_root *root); int write_ctree_super(struct btrfs_trans_handle *trans, struct btrfs_root *root); -int btrfs_read_dev_super(int fd, struct btrfs_super_block *sb, u64 sb_bytenr); +int btrfs_read_dev_super(int fd, struct btrfs_super_block *sb, u64 sb_bytenr, + int super_recover); int btrfs_map_bh_to_logical(struct btrfs_root *root, struct extent_buffer *bh, u64 logical); struct extent_buffer *btrfs_find_tree_block(struct btrfs_root *root, diff --git a/super-recover.c b/super-recover.c index cd6ba37..767de4b 100644 --- a/super-recover.c +++ b/super-recover.c @@ -292,7 +292,7 @@ int btrfs_recover_superblocks(const char *dname, } init_recover_superblock(&recover); - ret = btrfs_scan_fs_devices(fd, dname, &recover.fs_devices, 0, 0); + ret = btrfs_scan_fs_devices(fd, dname, &recover.fs_devices, 0, 0, 1); close(fd); if (ret) { ret = 1; diff --git a/utils.c b/utils.c index e130849..b0c24b1 100644 --- a/utils.c +++ b/utils.c @@ -1017,7 +1017,7 @@ int check_mounted_where(int fd, const char *file, char *where, int size, /* scan the initial device */ ret = btrfs_scan_one_device(fd, file, &fs_devices_mnt, - &total_devs, BTRFS_SUPER_INFO_OFFSET); + &total_devs, BTRFS_SUPER_INFO_OFFSET, 0); is_btrfs = (ret >= 0); /* scan other devices */ @@ -1179,7 +1179,7 @@ again: } ret = btrfs_scan_one_device(fd, fullpath, &tmp_devices, &num_devices, - BTRFS_SUPER_INFO_OFFSET); + BTRFS_SUPER_INFO_OFFSET, 0); if (ret == 0 && run_ioctl > 0) { btrfs_register_one_device(fullpath); } @@ -1522,7 +1522,7 @@ scan_again: } ret = btrfs_scan_one_device(fd, fullpath, &tmp_devices, &num_devices, - BTRFS_SUPER_INFO_OFFSET); + BTRFS_SUPER_INFO_OFFSET, 0); if (ret == 0 && run_ioctl > 0) { btrfs_register_one_device(fullpath); } @@ -1696,7 +1696,8 @@ int get_fs_info(char *path, struct btrfs_ioctl_fs_info_args *fi_args, fi_args->num_devices = 1; disk_super = (struct btrfs_super_block *)buf; - ret = btrfs_read_dev_super(fd, disk_super, BTRFS_SUPER_INFO_OFFSET); + ret = btrfs_read_dev_super(fd, disk_super, + BTRFS_SUPER_INFO_OFFSET, 0); if (ret < 0) { ret = -EIO; goto out; @@ -2045,7 +2046,7 @@ int btrfs_scan_lblkid(int update_kernel) continue; } ret = btrfs_scan_one_device(fd, path, &tmp_devices, - &num_devices, BTRFS_SUPER_INFO_OFFSET); + &num_devices, BTRFS_SUPER_INFO_OFFSET, 0); if (ret) { printf("ERROR: could not scan %s\n", path); close (fd); diff --git a/volumes.c b/volumes.c index a61928c..fa17ce1 100644 --- a/volumes.c +++ b/volumes.c @@ -232,7 +232,7 @@ fail: int btrfs_scan_one_device(int fd, const char *path, struct btrfs_fs_devices **fs_devices_ret, - u64 *total_devs, u64 super_offset) + u64 *total_devs, u64 super_offset, int super_recover) { struct btrfs_super_block *disk_super; char *buf; @@ -245,7 +245,7 @@ int btrfs_scan_one_device(int fd, const char *path, goto error; } disk_super = (struct btrfs_super_block *)buf; - ret = btrfs_read_dev_super(fd, disk_super, super_offset); + ret = btrfs_read_dev_super(fd, disk_super, super_offset, super_recover); if (ret < 0) { ret = -EIO; goto error_brelse; diff --git a/volumes.h b/volumes.h index b1ff3d0..70afa54 100644 --- a/volumes.h +++ b/volumes.h @@ -178,7 +178,7 @@ int btrfs_update_device(struct btrfs_trans_handle *trans, struct btrfs_device *device); int btrfs_scan_one_device(int fd, const char *path, struct btrfs_fs_devices **fs_devices_ret, - u64 *total_devs, u64 super_offset); + u64 *total_devs, u64 super_offset, int super_recover); int btrfs_num_copies(struct btrfs_mapping_tree *map_tree, u64 logical, u64 len); struct list_head *btrfs_scanned_uuids(void); int btrfs_add_system_chunk(struct btrfs_trans_handle *trans, -- 2.0.1 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html