| /* SPDX-License-Identifier: LGPL-2.1-or-later */ |
| |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <inttypes.h> |
| #include <linux/btrfs_tree.h> |
| #include <linux/fs.h> |
| #include <linux/loop.h> |
| #include <linux/magic.h> |
| #include <stddef.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <sys/ioctl.h> |
| #include <sys/sysmacros.h> |
| #include <unistd.h> |
| |
| #include "alloc-util.h" |
| #include "blockdev-util.h" |
| #include "btrfs-util.h" |
| #include "chattr-util.h" |
| #include "copy.h" |
| #include "fd-util.h" |
| #include "fileio.h" |
| #include "fs-util.h" |
| #include "io-util.h" |
| #include "macro.h" |
| #include "path-util.h" |
| #include "rm-rf.h" |
| #include "smack-util.h" |
| #include "sparse-endian.h" |
| #include "stat-util.h" |
| #include "string-util.h" |
| #include "time-util.h" |
| |
| /* WARNING: Be careful with file system ioctls! When we get an fd, we |
| * need to make sure it either refers to only a regular file or |
| * directory, or that it is located on btrfs, before invoking any |
| * btrfs ioctls. The ioctl numbers are reused by some device drivers |
| * (such as DRM), and hence might have bad effects when invoked on |
| * device nodes (that reference drivers) rather than fds to normal |
| * files or directories. */ |
| |
| static int validate_subvolume_name(const char *name) { |
| |
| if (!filename_is_valid(name)) |
| return -EINVAL; |
| |
| if (strlen(name) > BTRFS_SUBVOL_NAME_MAX) |
| return -E2BIG; |
| |
| return 0; |
| } |
| |
| static int extract_subvolume_name(const char *path, char **ret) { |
| _cleanup_free_ char *fn = NULL; |
| int r; |
| |
| assert(path); |
| assert(ret); |
| |
| r = path_extract_filename(path, &fn); |
| if (r < 0) |
| return r; |
| |
| r = validate_subvolume_name(fn); |
| if (r < 0) |
| return r; |
| |
| *ret = TAKE_PTR(fn); |
| return 0; |
| } |
| |
| int btrfs_is_subvol_fd(int fd) { |
| struct stat st; |
| |
| assert(fd >= 0); |
| |
| /* On btrfs subvolumes always have the inode 256 */ |
| |
| if (fstat(fd, &st) < 0) |
| return -errno; |
| |
| if (!btrfs_might_be_subvol(&st)) |
| return 0; |
| |
| return fd_is_fs_type(fd, BTRFS_SUPER_MAGIC); |
| } |
| |
| int btrfs_is_subvol(const char *path) { |
| _cleanup_close_ int fd = -EBADF; |
| |
| assert(path); |
| |
| fd = open(path, O_RDONLY|O_NOCTTY|O_CLOEXEC|O_DIRECTORY); |
| if (fd < 0) |
| return -errno; |
| |
| return btrfs_is_subvol_fd(fd); |
| } |
| |
| int btrfs_subvol_make_fd(int fd, const char *subvolume) { |
| struct btrfs_ioctl_vol_args args = {}; |
| _cleanup_close_ int real_fd = -EBADF; |
| int r; |
| |
| assert(subvolume); |
| |
| r = validate_subvolume_name(subvolume); |
| if (r < 0) |
| return r; |
| |
| /* If an O_PATH fd was specified, let's convert here to a proper one, as btrfs ioctl's can't deal |
| * with O_PATH. */ |
| fd = fd_reopen_condition(fd, O_RDONLY|O_CLOEXEC|O_DIRECTORY, O_PATH|O_DIRECTORY, &real_fd); |
| if (fd < 0) |
| return fd; |
| |
| strncpy(args.name, subvolume, sizeof(args.name)-1); |
| |
| return RET_NERRNO(ioctl(fd, BTRFS_IOC_SUBVOL_CREATE, &args)); |
| } |
| |
| int btrfs_subvol_make(const char *path) { |
| _cleanup_free_ char *subvolume = NULL; |
| _cleanup_close_ int fd = -EBADF; |
| int r; |
| |
| assert(path); |
| |
| r = extract_subvolume_name(path, &subvolume); |
| if (r < 0) |
| return r; |
| |
| fd = open_parent(path, O_CLOEXEC, 0); |
| if (fd < 0) |
| return fd; |
| |
| return btrfs_subvol_make_fd(fd, subvolume); |
| } |
| |
| int btrfs_subvol_make_fallback(const char *path, mode_t mode) { |
| mode_t old, combined; |
| int r; |
| |
| assert(path); |
| |
| /* Let's work like mkdir(), i.e. take the specified mode, and mask it with the current umask. */ |
| old = umask(~mode); |
| combined = old | ~mode; |
| if (combined != ~mode) |
| umask(combined); |
| r = btrfs_subvol_make(path); |
| umask(old); |
| |
| if (r >= 0) |
| return 1; /* subvol worked */ |
| if (r != -ENOTTY) |
| return r; |
| |
| if (mkdir(path, mode) < 0) |
| return -errno; |
| |
| return 0; /* plain directory */ |
| } |
| |
| int btrfs_subvol_set_read_only_fd(int fd, bool b) { |
| uint64_t flags, nflags; |
| struct stat st; |
| |
| assert(fd >= 0); |
| |
| if (fstat(fd, &st) < 0) |
| return -errno; |
| |
| if (!btrfs_might_be_subvol(&st)) |
| return -EINVAL; |
| |
| if (ioctl(fd, BTRFS_IOC_SUBVOL_GETFLAGS, &flags) < 0) |
| return -errno; |
| |
| nflags = UPDATE_FLAG(flags, BTRFS_SUBVOL_RDONLY, b); |
| if (flags == nflags) |
| return 0; |
| |
| return RET_NERRNO(ioctl(fd, BTRFS_IOC_SUBVOL_SETFLAGS, &nflags)); |
| } |
| |
| int btrfs_subvol_set_read_only(const char *path, bool b) { |
| _cleanup_close_ int fd = -EBADF; |
| |
| fd = open(path, O_RDONLY|O_NOCTTY|O_CLOEXEC|O_DIRECTORY); |
| if (fd < 0) |
| return -errno; |
| |
| return btrfs_subvol_set_read_only_fd(fd, b); |
| } |
| |
| int btrfs_subvol_get_read_only_fd(int fd) { |
| uint64_t flags; |
| struct stat st; |
| |
| assert(fd >= 0); |
| |
| if (fstat(fd, &st) < 0) |
| return -errno; |
| |
| if (!btrfs_might_be_subvol(&st)) |
| return -EINVAL; |
| |
| if (ioctl(fd, BTRFS_IOC_SUBVOL_GETFLAGS, &flags) < 0) |
| return -errno; |
| |
| return !!(flags & BTRFS_SUBVOL_RDONLY); |
| } |
| |
| int btrfs_reflink(int infd, int outfd) { |
| int r; |
| |
| assert(infd >= 0); |
| assert(outfd >= 0); |
| |
| /* Make sure we invoke the ioctl on a regular file, so that no device driver accidentally gets it. */ |
| |
| r = fd_verify_regular(outfd); |
| if (r < 0) |
| return r; |
| |
| return RET_NERRNO(ioctl(outfd, BTRFS_IOC_CLONE, infd)); |
| } |
| |
| int btrfs_clone_range(int infd, uint64_t in_offset, int outfd, uint64_t out_offset, uint64_t sz) { |
| struct btrfs_ioctl_clone_range_args args = { |
| .src_fd = infd, |
| .src_offset = in_offset, |
| .src_length = sz, |
| .dest_offset = out_offset, |
| }; |
| int r; |
| |
| assert(infd >= 0); |
| assert(outfd >= 0); |
| |
| r = fd_verify_regular(outfd); |
| if (r < 0) |
| return r; |
| |
| return RET_NERRNO(ioctl(outfd, BTRFS_IOC_CLONE_RANGE, &args)); |
| } |
| |
| int btrfs_get_block_device_fd(int fd, dev_t *dev) { |
| struct btrfs_ioctl_fs_info_args fsi = {}; |
| _cleanup_close_ int regfd = -EBADF; |
| uint64_t id; |
| int r; |
| |
| assert(fd >= 0); |
| assert(dev); |
| |
| fd = fd_reopen_condition(fd, O_RDONLY|O_CLOEXEC|O_NONBLOCK|O_NOCTTY, O_PATH, ®fd); |
| if (fd < 0) |
| return fd; |
| |
| r = fd_is_fs_type(fd, BTRFS_SUPER_MAGIC); |
| if (r < 0) |
| return r; |
| if (!r) |
| return -ENOTTY; |
| |
| if (ioctl(fd, BTRFS_IOC_FS_INFO, &fsi) < 0) |
| return -errno; |
| |
| /* We won't do this for btrfs RAID */ |
| if (fsi.num_devices != 1) { |
| *dev = 0; |
| return 0; |
| } |
| |
| for (id = 1; id <= fsi.max_id; id++) { |
| struct btrfs_ioctl_dev_info_args di = { |
| .devid = id, |
| }; |
| struct stat st; |
| |
| if (ioctl(fd, BTRFS_IOC_DEV_INFO, &di) < 0) { |
| if (errno == ENODEV) |
| continue; |
| |
| return -errno; |
| } |
| |
| /* For the root fs — when no initrd is involved — btrfs returns /dev/root on any kernels from |
| * the past few years. That sucks, as we have no API to determine the actual root then. let's |
| * return an recognizable error for this case, so that the caller can maybe print a nice |
| * message about this. |
| * |
| * https://bugzilla.kernel.org/show_bug.cgi?id=89721 */ |
| if (path_equal((char*) di.path, "/dev/root")) |
| return -EUCLEAN; |
| |
| if (stat((char*) di.path, &st) < 0) |
| return -errno; |
| |
| if (!S_ISBLK(st.st_mode)) |
| return -ENOTBLK; |
| |
| if (major(st.st_rdev) == 0) |
| return -ENODEV; |
| |
| *dev = st.st_rdev; |
| return 1; |
| } |
| |
| return -ENODEV; |
| } |
| |
| int btrfs_get_block_device(const char *path, dev_t *dev) { |
| _cleanup_close_ int fd = -EBADF; |
| |
| assert(path); |
| assert(dev); |
| |
| fd = open(path, O_RDONLY|O_NOCTTY|O_CLOEXEC); |
| if (fd < 0) |
| return -errno; |
| |
| return btrfs_get_block_device_fd(fd, dev); |
| } |
| |
| int btrfs_subvol_get_id_fd(int fd, uint64_t *ret) { |
| struct btrfs_ioctl_ino_lookup_args args = { |
| .objectid = BTRFS_FIRST_FREE_OBJECTID |
| }; |
| int r; |
| |
| assert(fd >= 0); |
| assert(ret); |
| |
| r = fd_is_fs_type(fd, BTRFS_SUPER_MAGIC); |
| if (r < 0) |
| return r; |
| if (!r) |
| return -ENOTTY; |
| |
| if (ioctl(fd, BTRFS_IOC_INO_LOOKUP, &args) < 0) |
| return -errno; |
| |
| *ret = args.treeid; |
| return 0; |
| } |
| |
| int btrfs_subvol_get_id(int fd, const char *subvol, uint64_t *ret) { |
| _cleanup_close_ int subvol_fd = -EBADF; |
| |
| assert(fd >= 0); |
| assert(ret); |
| |
| subvol_fd = openat(fd, subvol, O_RDONLY|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW); |
| if (subvol_fd < 0) |
| return -errno; |
| |
| return btrfs_subvol_get_id_fd(subvol_fd, ret); |
| } |
| |
| static bool btrfs_ioctl_search_args_inc(struct btrfs_ioctl_search_args *args) { |
| assert(args); |
| |
| /* the objectid, type, offset together make up the btrfs key, |
| * which is considered a single 136byte integer when |
| * comparing. This call increases the counter by one, dealing |
| * with the overflow between the overflows */ |
| |
| if (args->key.min_offset < UINT64_MAX) { |
| args->key.min_offset++; |
| return true; |
| } |
| |
| if (args->key.min_type < UINT8_MAX) { |
| args->key.min_type++; |
| args->key.min_offset = 0; |
| return true; |
| } |
| |
| if (args->key.min_objectid < UINT64_MAX) { |
| args->key.min_objectid++; |
| args->key.min_offset = 0; |
| args->key.min_type = 0; |
| return true; |
| } |
| |
| return 0; |
| } |
| |
| static void btrfs_ioctl_search_args_set(struct btrfs_ioctl_search_args *args, const struct btrfs_ioctl_search_header *h) { |
| assert(args); |
| assert(h); |
| |
| args->key.min_objectid = h->objectid; |
| args->key.min_type = h->type; |
| args->key.min_offset = h->offset; |
| } |
| |
| static int btrfs_ioctl_search_args_compare(const struct btrfs_ioctl_search_args *args) { |
| int r; |
| |
| assert(args); |
| |
| /* Compare min and max */ |
| |
| r = CMP(args->key.min_objectid, args->key.max_objectid); |
| if (r != 0) |
| return r; |
| |
| r = CMP(args->key.min_type, args->key.max_type); |
| if (r != 0) |
| return r; |
| |
| return CMP(args->key.min_offset, args->key.max_offset); |
| } |
| |
| #define FOREACH_BTRFS_IOCTL_SEARCH_HEADER(i, sh, args) \ |
| for ((i) = 0, \ |
| (sh) = (const struct btrfs_ioctl_search_header*) (args).buf; \ |
| (i) < (args).key.nr_items; \ |
| (i)++, \ |
| (sh) = (const struct btrfs_ioctl_search_header*) ((uint8_t*) (sh) + sizeof(struct btrfs_ioctl_search_header) + (sh)->len)) |
| |
| #define BTRFS_IOCTL_SEARCH_HEADER_BODY(sh) \ |
| ((void*) ((uint8_t*) sh + sizeof(struct btrfs_ioctl_search_header))) |
| |
| int btrfs_subvol_get_info_fd(int fd, uint64_t subvol_id, BtrfsSubvolInfo *ret) { |
| struct btrfs_ioctl_search_args args = { |
| /* Tree of tree roots */ |
| .key.tree_id = BTRFS_ROOT_TREE_OBJECTID, |
| |
| /* Look precisely for the subvolume items */ |
| .key.min_type = BTRFS_ROOT_ITEM_KEY, |
| .key.max_type = BTRFS_ROOT_ITEM_KEY, |
| |
| .key.min_offset = 0, |
| .key.max_offset = UINT64_MAX, |
| |
| /* No restrictions on the other components */ |
| .key.min_transid = 0, |
| .key.max_transid = UINT64_MAX, |
| }; |
| |
| bool found = false; |
| int r; |
| |
| assert(fd >= 0); |
| assert(ret); |
| |
| if (subvol_id == 0) { |
| r = btrfs_subvol_get_id_fd(fd, &subvol_id); |
| if (r < 0) |
| return r; |
| } else { |
| r = fd_is_fs_type(fd, BTRFS_SUPER_MAGIC); |
| if (r < 0) |
| return r; |
| if (!r) |
| return -ENOTTY; |
| } |
| |
| args.key.min_objectid = args.key.max_objectid = subvol_id; |
| |
| while (btrfs_ioctl_search_args_compare(&args) <= 0) { |
| const struct btrfs_ioctl_search_header *sh; |
| unsigned i; |
| |
| args.key.nr_items = 256; |
| if (ioctl(fd, BTRFS_IOC_TREE_SEARCH, &args) < 0) |
| return -errno; |
| |
| if (args.key.nr_items <= 0) |
| break; |
| |
| FOREACH_BTRFS_IOCTL_SEARCH_HEADER(i, sh, args) { |
| |
| const struct btrfs_root_item *ri; |
| |
| /* Make sure we start the next search at least from this entry */ |
| btrfs_ioctl_search_args_set(&args, sh); |
| |
| if (sh->objectid != subvol_id) |
| continue; |
| if (sh->type != BTRFS_ROOT_ITEM_KEY) |
| continue; |
| |
| /* Older versions of the struct lacked the otime setting */ |
| if (sh->len < offsetof(struct btrfs_root_item, otime) + sizeof(struct btrfs_timespec)) |
| continue; |
| |
| ri = BTRFS_IOCTL_SEARCH_HEADER_BODY(sh); |
| |
| ret->otime = (usec_t) le64toh(ri->otime.sec) * USEC_PER_SEC + |
| (usec_t) le32toh(ri->otime.nsec) / NSEC_PER_USEC; |
| |
| ret->subvol_id = subvol_id; |
| ret->read_only = le64toh(ri->flags) & BTRFS_ROOT_SUBVOL_RDONLY; |
| |
| assert_cc(sizeof(ri->uuid) == sizeof(ret->uuid)); |
| memcpy(&ret->uuid, ri->uuid, sizeof(ret->uuid)); |
| memcpy(&ret->parent_uuid, ri->parent_uuid, sizeof(ret->parent_uuid)); |
| |
| found = true; |
| goto finish; |
| } |
| |
| /* Increase search key by one, to read the next item, if we can. */ |
| if (!btrfs_ioctl_search_args_inc(&args)) |
| break; |
| } |
| |
| finish: |
| return found ? 0 : -ENODATA; |
| } |
| |
| int btrfs_qgroup_get_quota_fd(int fd, uint64_t qgroupid, BtrfsQuotaInfo *ret) { |
| |
| struct btrfs_ioctl_search_args args = { |
| /* Tree of quota items */ |
| .key.tree_id = BTRFS_QUOTA_TREE_OBJECTID, |
| |
| /* The object ID is always 0 */ |
| .key.min_objectid = 0, |
| .key.max_objectid = 0, |
| |
| /* Look precisely for the quota items */ |
| .key.min_type = BTRFS_QGROUP_STATUS_KEY, |
| .key.max_type = BTRFS_QGROUP_LIMIT_KEY, |
| |
| /* No restrictions on the other components */ |
| .key.min_transid = 0, |
| .key.max_transid = UINT64_MAX, |
| }; |
| |
| bool found_info = false, found_limit = false; |
| int r; |
| |
| assert(fd >= 0); |
| assert(ret); |
| |
| if (qgroupid == 0) { |
| r = btrfs_subvol_get_id_fd(fd, &qgroupid); |
| if (r < 0) |
| return r; |
| } else { |
| r = fd_is_fs_type(fd, BTRFS_SUPER_MAGIC); |
| if (r < 0) |
| return r; |
| if (!r) |
| return -ENOTTY; |
| } |
| |
| args.key.min_offset = args.key.max_offset = qgroupid; |
| |
| while (btrfs_ioctl_search_args_compare(&args) <= 0) { |
| const struct btrfs_ioctl_search_header *sh; |
| unsigned i; |
| |
| args.key.nr_items = 256; |
| if (ioctl(fd, BTRFS_IOC_TREE_SEARCH, &args) < 0) { |
| if (errno == ENOENT) /* quota tree is missing: quota disabled */ |
| break; |
| |
| return -errno; |
| } |
| |
| if (args.key.nr_items <= 0) |
| break; |
| |
| FOREACH_BTRFS_IOCTL_SEARCH_HEADER(i, sh, args) { |
| |
| /* Make sure we start the next search at least from this entry */ |
| btrfs_ioctl_search_args_set(&args, sh); |
| |
| if (sh->objectid != 0) |
| continue; |
| if (sh->offset != qgroupid) |
| continue; |
| |
| if (sh->type == BTRFS_QGROUP_INFO_KEY) { |
| const struct btrfs_qgroup_info_item *qii = BTRFS_IOCTL_SEARCH_HEADER_BODY(sh); |
| |
| ret->referenced = le64toh(qii->rfer); |
| ret->exclusive = le64toh(qii->excl); |
| |
| found_info = true; |
| |
| } else if (sh->type == BTRFS_QGROUP_LIMIT_KEY) { |
| const struct btrfs_qgroup_limit_item *qli = BTRFS_IOCTL_SEARCH_HEADER_BODY(sh); |
| |
| if (le64toh(qli->flags) & BTRFS_QGROUP_LIMIT_MAX_RFER) |
| ret->referenced_max = le64toh(qli->max_rfer); |
| else |
| ret->referenced_max = UINT64_MAX; |
| |
| if (le64toh(qli->flags) & BTRFS_QGROUP_LIMIT_MAX_EXCL) |
| ret->exclusive_max = le64toh(qli->max_excl); |
| else |
| ret->exclusive_max = UINT64_MAX; |
| |
| found_limit = true; |
| } |
| |
| if (found_info && found_limit) |
| goto finish; |
| } |
| |
| /* Increase search key by one, to read the next item, if we can. */ |
| if (!btrfs_ioctl_search_args_inc(&args)) |
| break; |
| } |
| |
| finish: |
| if (!found_limit && !found_info) |
| return -ENODATA; |
| |
| if (!found_info) { |
| ret->referenced = UINT64_MAX; |
| ret->exclusive = UINT64_MAX; |
| } |
| |
| if (!found_limit) { |
| ret->referenced_max = UINT64_MAX; |
| ret->exclusive_max = UINT64_MAX; |
| } |
| |
| return 0; |
| } |
| |
| int btrfs_qgroup_get_quota(const char *path, uint64_t qgroupid, BtrfsQuotaInfo *ret) { |
| _cleanup_close_ int fd = -EBADF; |
| |
| fd = open(path, O_RDONLY|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW); |
| if (fd < 0) |
| return -errno; |
| |
| return btrfs_qgroup_get_quota_fd(fd, qgroupid, ret); |
| } |
| |
| int btrfs_subvol_find_subtree_qgroup(int fd, uint64_t subvol_id, uint64_t *ret) { |
| uint64_t level, lowest = UINT64_MAX, lowest_qgroupid = 0; |
| _cleanup_free_ uint64_t *qgroups = NULL; |
| int r, n; |
| |
| assert(fd >= 0); |
| assert(ret); |
| |
| /* This finds the "subtree" qgroup for a specific |
| * subvolume. This only works for subvolumes that have been |
| * prepared with btrfs_subvol_auto_qgroup_fd() with |
| * insert_intermediary_qgroup=true (or equivalent). For others |
| * it will return the leaf qgroup instead. The two cases may |
| * be distinguished via the return value, which is 1 in case |
| * an appropriate "subtree" qgroup was found, and 0 |
| * otherwise. */ |
| |
| if (subvol_id == 0) { |
| r = btrfs_subvol_get_id_fd(fd, &subvol_id); |
| if (r < 0) |
| return r; |
| } |
| |
| r = btrfs_qgroupid_split(subvol_id, &level, NULL); |
| if (r < 0) |
| return r; |
| if (level != 0) /* Input must be a leaf qgroup */ |
| return -EINVAL; |
| |
| n = btrfs_qgroup_find_parents(fd, subvol_id, &qgroups); |
| if (n < 0) |
| return n; |
| |
| for (int i = 0; i < n; i++) { |
| uint64_t id; |
| |
| r = btrfs_qgroupid_split(qgroups[i], &level, &id); |
| if (r < 0) |
| return r; |
| |
| if (id != subvol_id) |
| continue; |
| |
| if (lowest == UINT64_MAX || level < lowest) { |
| lowest_qgroupid = qgroups[i]; |
| lowest = level; |
| } |
| } |
| |
| if (lowest == UINT64_MAX) { |
| /* No suitable higher-level qgroup found, let's return |
| * the leaf qgroup instead, and indicate that with the |
| * return value. */ |
| |
| *ret = subvol_id; |
| return 0; |
| } |
| |
| *ret = lowest_qgroupid; |
| return 1; |
| } |
| |
| int btrfs_subvol_get_subtree_quota_fd(int fd, uint64_t subvol_id, BtrfsQuotaInfo *ret) { |
| uint64_t qgroupid; |
| int r; |
| |
| assert(fd >= 0); |
| assert(ret); |
| |
| /* This determines the quota data of the qgroup with the |
| * lowest level, that shares the id part with the specified |
| * subvolume. This is useful for determining the quota data |
| * for entire subvolume subtrees, as long as the subtrees have |
| * been set up with btrfs_qgroup_subvol_auto_fd() or in a |
| * compatible way */ |
| |
| r = btrfs_subvol_find_subtree_qgroup(fd, subvol_id, &qgroupid); |
| if (r < 0) |
| return r; |
| |
| return btrfs_qgroup_get_quota_fd(fd, qgroupid, ret); |
| } |
| |
| int btrfs_subvol_get_subtree_quota(const char *path, uint64_t subvol_id, BtrfsQuotaInfo *ret) { |
| _cleanup_close_ int fd = -EBADF; |
| |
| fd = open(path, O_RDONLY|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW); |
| if (fd < 0) |
| return -errno; |
| |
| return btrfs_subvol_get_subtree_quota_fd(fd, subvol_id, ret); |
| } |
| |
| int btrfs_defrag_fd(int fd) { |
| int r; |
| |
| assert(fd >= 0); |
| |
| r = fd_verify_regular(fd); |
| if (r < 0) |
| return r; |
| |
| return RET_NERRNO(ioctl(fd, BTRFS_IOC_DEFRAG, NULL)); |
| } |
| |
| int btrfs_defrag(const char *p) { |
| _cleanup_close_ int fd = -EBADF; |
| |
| fd = open(p, O_RDWR|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW); |
| if (fd < 0) |
| return -errno; |
| |
| return btrfs_defrag_fd(fd); |
| } |
| |
| int btrfs_quota_enable_fd(int fd, bool b) { |
| struct btrfs_ioctl_quota_ctl_args args = { |
| .cmd = b ? BTRFS_QUOTA_CTL_ENABLE : BTRFS_QUOTA_CTL_DISABLE, |
| }; |
| int r; |
| |
| assert(fd >= 0); |
| |
| r = fd_is_fs_type(fd, BTRFS_SUPER_MAGIC); |
| if (r < 0) |
| return r; |
| if (!r) |
| return -ENOTTY; |
| |
| return RET_NERRNO(ioctl(fd, BTRFS_IOC_QUOTA_CTL, &args)); |
| } |
| |
| int btrfs_quota_enable(const char *path, bool b) { |
| _cleanup_close_ int fd = -EBADF; |
| |
| fd = open(path, O_RDONLY|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW); |
| if (fd < 0) |
| return -errno; |
| |
| return btrfs_quota_enable_fd(fd, b); |
| } |
| |
| int btrfs_qgroup_set_limit_fd(int fd, uint64_t qgroupid, uint64_t referenced_max) { |
| |
| struct btrfs_ioctl_qgroup_limit_args args = { |
| .lim.max_rfer = referenced_max, |
| .lim.flags = BTRFS_QGROUP_LIMIT_MAX_RFER, |
| }; |
| int r; |
| |
| assert(fd >= 0); |
| |
| if (qgroupid == 0) { |
| r = btrfs_subvol_get_id_fd(fd, &qgroupid); |
| if (r < 0) |
| return r; |
| } else { |
| r = fd_is_fs_type(fd, BTRFS_SUPER_MAGIC); |
| if (r < 0) |
| return r; |
| if (!r) |
| return -ENOTTY; |
| } |
| |
| args.qgroupid = qgroupid; |
| |
| for (unsigned c = 0;; c++) { |
| if (ioctl(fd, BTRFS_IOC_QGROUP_LIMIT, &args) < 0) { |
| |
| if (errno == EBUSY && c < 10) { |
| (void) btrfs_quota_scan_wait(fd); |
| continue; |
| } |
| |
| return -errno; |
| } |
| |
| break; |
| } |
| |
| return 0; |
| } |
| |
| int btrfs_qgroup_set_limit(const char *path, uint64_t qgroupid, uint64_t referenced_max) { |
| _cleanup_close_ int fd = -EBADF; |
| |
| fd = open(path, O_RDONLY|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW); |
| if (fd < 0) |
| return -errno; |
| |
| return btrfs_qgroup_set_limit_fd(fd, qgroupid, referenced_max); |
| } |
| |
| int btrfs_subvol_set_subtree_quota_limit_fd(int fd, uint64_t subvol_id, uint64_t referenced_max) { |
| uint64_t qgroupid; |
| int r; |
| |
| assert(fd >= 0); |
| |
| r = btrfs_subvol_find_subtree_qgroup(fd, subvol_id, &qgroupid); |
| if (r < 0) |
| return r; |
| |
| return btrfs_qgroup_set_limit_fd(fd, qgroupid, referenced_max); |
| } |
| |
| int btrfs_subvol_set_subtree_quota_limit(const char *path, uint64_t subvol_id, uint64_t referenced_max) { |
| _cleanup_close_ int fd = -EBADF; |
| |
| fd = open(path, O_RDONLY|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW); |
| if (fd < 0) |
| return -errno; |
| |
| return btrfs_subvol_set_subtree_quota_limit_fd(fd, subvol_id, referenced_max); |
| } |
| |
| int btrfs_qgroupid_make(uint64_t level, uint64_t id, uint64_t *ret) { |
| assert(ret); |
| |
| if (level >= (UINT64_C(1) << (64 - BTRFS_QGROUP_LEVEL_SHIFT))) |
| return -EINVAL; |
| |
| if (id >= (UINT64_C(1) << BTRFS_QGROUP_LEVEL_SHIFT)) |
| return -EINVAL; |
| |
| *ret = (level << BTRFS_QGROUP_LEVEL_SHIFT) | id; |
| return 0; |
| } |
| |
| int btrfs_qgroupid_split(uint64_t qgroupid, uint64_t *level, uint64_t *id) { |
| assert(level || id); |
| |
| if (level) |
| *level = qgroupid >> BTRFS_QGROUP_LEVEL_SHIFT; |
| |
| if (id) |
| *id = qgroupid & ((UINT64_C(1) << BTRFS_QGROUP_LEVEL_SHIFT) - 1); |
| |
| return 0; |
| } |
| |
| static int qgroup_create_or_destroy(int fd, bool b, uint64_t qgroupid) { |
| |
| struct btrfs_ioctl_qgroup_create_args args = { |
| .create = b, |
| .qgroupid = qgroupid, |
| }; |
| int r; |
| |
| r = fd_is_fs_type(fd, BTRFS_SUPER_MAGIC); |
| if (r < 0) |
| return r; |
| if (r == 0) |
| return -ENOTTY; |
| |
| for (unsigned c = 0;; c++) { |
| if (ioctl(fd, BTRFS_IOC_QGROUP_CREATE, &args) < 0) { |
| |
| /* On old kernels if quota is not enabled, we get EINVAL. On newer kernels we get |
| * ENOTCONN. Let's always convert this to ENOTCONN to make this recognizable |
| * everywhere the same way. */ |
| |
| if (IN_SET(errno, EINVAL, ENOTCONN)) |
| return -ENOTCONN; |
| |
| if (errno == EBUSY && c < 10) { |
| (void) btrfs_quota_scan_wait(fd); |
| continue; |
| } |
| |
| return -errno; |
| } |
| |
| break; |
| } |
| |
| return 0; |
| } |
| |
| int btrfs_qgroup_create(int fd, uint64_t qgroupid) { |
| return qgroup_create_or_destroy(fd, true, qgroupid); |
| } |
| |
| int btrfs_qgroup_destroy(int fd, uint64_t qgroupid) { |
| return qgroup_create_or_destroy(fd, false, qgroupid); |
| } |
| |
| int btrfs_qgroup_destroy_recursive(int fd, uint64_t qgroupid) { |
| _cleanup_free_ uint64_t *qgroups = NULL; |
| uint64_t subvol_id; |
| int n, r; |
| |
| /* Destroys the specified qgroup, but unassigns it from all |
| * its parents first. Also, it recursively destroys all |
| * qgroups it is assigned to that have the same id part of the |
| * qgroupid as the specified group. */ |
| |
| r = btrfs_qgroupid_split(qgroupid, NULL, &subvol_id); |
| if (r < 0) |
| return r; |
| |
| n = btrfs_qgroup_find_parents(fd, qgroupid, &qgroups); |
| if (n < 0) |
| return n; |
| |
| for (int i = 0; i < n; i++) { |
| uint64_t id; |
| |
| r = btrfs_qgroupid_split(qgroups[i], NULL, &id); |
| if (r < 0) |
| return r; |
| |
| r = btrfs_qgroup_unassign(fd, qgroupid, qgroups[i]); |
| if (r < 0) |
| return r; |
| |
| if (id != subvol_id) |
| continue; |
| |
| /* The parent qgroupid shares the same id part with |
| * us? If so, destroy it too. */ |
| |
| (void) btrfs_qgroup_destroy_recursive(fd, qgroups[i]); |
| } |
| |
| return btrfs_qgroup_destroy(fd, qgroupid); |
| } |
| |
| int btrfs_quota_scan_start(int fd) { |
| struct btrfs_ioctl_quota_rescan_args args = {}; |
| |
| assert(fd >= 0); |
| |
| return RET_NERRNO(ioctl(fd, BTRFS_IOC_QUOTA_RESCAN, &args)); |
| } |
| |
| int btrfs_quota_scan_wait(int fd) { |
| assert(fd >= 0); |
| |
| return RET_NERRNO(ioctl(fd, BTRFS_IOC_QUOTA_RESCAN_WAIT)); |
| } |
| |
| int btrfs_quota_scan_ongoing(int fd) { |
| struct btrfs_ioctl_quota_rescan_args args = {}; |
| |
| assert(fd >= 0); |
| |
| if (ioctl(fd, BTRFS_IOC_QUOTA_RESCAN_STATUS, &args) < 0) |
| return -errno; |
| |
| return !!args.flags; |
| } |
| |
| static int qgroup_assign_or_unassign(int fd, bool b, uint64_t child, uint64_t parent) { |
| struct btrfs_ioctl_qgroup_assign_args args = { |
| .assign = b, |
| .src = child, |
| .dst = parent, |
| }; |
| int r; |
| |
| r = fd_is_fs_type(fd, BTRFS_SUPER_MAGIC); |
| if (r < 0) |
| return r; |
| if (r == 0) |
| return -ENOTTY; |
| |
| for (unsigned c = 0;; c++) { |
| r = ioctl(fd, BTRFS_IOC_QGROUP_ASSIGN, &args); |
| if (r < 0) { |
| if (errno == EBUSY && c < 10) { |
| (void) btrfs_quota_scan_wait(fd); |
| continue; |
| } |
| |
| return -errno; |
| } |
| |
| if (r == 0) |
| return 0; |
| |
| /* If the return value is > 0, we need to request a rescan */ |
| |
| (void) btrfs_quota_scan_start(fd); |
| return 1; |
| } |
| } |
| |
| int btrfs_qgroup_assign(int fd, uint64_t child, uint64_t parent) { |
| return qgroup_assign_or_unassign(fd, true, child, parent); |
| } |
| |
| int btrfs_qgroup_unassign(int fd, uint64_t child, uint64_t parent) { |
| return qgroup_assign_or_unassign(fd, false, child, parent); |
| } |
| |
| static int subvol_remove_children(int fd, const char *subvolume, uint64_t subvol_id, BtrfsRemoveFlags flags) { |
| struct btrfs_ioctl_search_args args = { |
| .key.tree_id = BTRFS_ROOT_TREE_OBJECTID, |
| |
| .key.min_objectid = BTRFS_FIRST_FREE_OBJECTID, |
| .key.max_objectid = BTRFS_LAST_FREE_OBJECTID, |
| |
| .key.min_type = BTRFS_ROOT_BACKREF_KEY, |
| .key.max_type = BTRFS_ROOT_BACKREF_KEY, |
| |
| .key.min_transid = 0, |
| .key.max_transid = UINT64_MAX, |
| }; |
| |
| struct btrfs_ioctl_vol_args vol_args = {}; |
| _cleanup_close_ int subvol_fd = -EBADF; |
| struct stat st; |
| bool made_writable = false; |
| int r; |
| |
| assert(fd >= 0); |
| assert(subvolume); |
| |
| if (fstat(fd, &st) < 0) |
| return -errno; |
| |
| if (!S_ISDIR(st.st_mode)) |
| return -EINVAL; |
| |
| subvol_fd = openat(fd, subvolume, O_RDONLY|O_NOCTTY|O_CLOEXEC|O_DIRECTORY|O_NOFOLLOW); |
| if (subvol_fd < 0) |
| return -errno; |
| |
| /* Let's check if this is actually a subvolume. Note that this is mostly redundant, as BTRFS_IOC_SNAP_DESTROY |
| * would fail anyway if it is not. However, it's a good thing to check this ahead of time so that we can return |
| * ENOTTY unconditionally in this case. This is different from the ioctl() which will return EPERM/EACCES if we |
| * don't have the privileges to remove subvolumes, regardless if the specified directory is actually a |
| * subvolume or not. In order to make it easy for callers to cover the "this is not a btrfs subvolume" case |
| * let's prefer ENOTTY over EPERM/EACCES though. */ |
| r = btrfs_is_subvol_fd(subvol_fd); |
| if (r < 0) |
| return r; |
| if (r == 0) /* Not a btrfs subvolume */ |
| return -ENOTTY; |
| |
| if (subvol_id == 0) { |
| r = btrfs_subvol_get_id_fd(subvol_fd, &subvol_id); |
| if (r < 0) |
| return r; |
| } |
| |
| /* First, try to remove the subvolume. If it happens to be |
| * already empty, this will just work. */ |
| strncpy(vol_args.name, subvolume, sizeof(vol_args.name)-1); |
| if (ioctl(fd, BTRFS_IOC_SNAP_DESTROY, &vol_args) >= 0) { |
| (void) btrfs_qgroup_destroy_recursive(fd, subvol_id); /* for the leaf subvolumes, the qgroup id is identical to the subvol id */ |
| return 0; |
| } |
| if (!(flags & BTRFS_REMOVE_RECURSIVE) || errno != ENOTEMPTY) |
| return -errno; |
| |
| /* OK, the subvolume is not empty, let's look for child |
| * subvolumes, and remove them, first */ |
| |
| args.key.min_offset = args.key.max_offset = subvol_id; |
| |
| while (btrfs_ioctl_search_args_compare(&args) <= 0) { |
| const struct btrfs_ioctl_search_header *sh; |
| unsigned i; |
| |
| args.key.nr_items = 256; |
| if (ioctl(fd, BTRFS_IOC_TREE_SEARCH, &args) < 0) |
| return -errno; |
| |
| if (args.key.nr_items <= 0) |
| break; |
| |
| FOREACH_BTRFS_IOCTL_SEARCH_HEADER(i, sh, args) { |
| _cleanup_free_ char *p = NULL; |
| const struct btrfs_root_ref *ref; |
| |
| btrfs_ioctl_search_args_set(&args, sh); |
| |
| if (sh->type != BTRFS_ROOT_BACKREF_KEY) |
| continue; |
| if (sh->offset != subvol_id) |
| continue; |
| |
| ref = BTRFS_IOCTL_SEARCH_HEADER_BODY(sh); |
| |
| p = strndup((char*) ref + sizeof(struct btrfs_root_ref), le64toh(ref->name_len)); |
| if (!p) |
| return -ENOMEM; |
| |
| struct btrfs_ioctl_ino_lookup_args ino_args = { |
| .treeid = subvol_id, |
| .objectid = htole64(ref->dirid), |
| }; |
| |
| if (ioctl(fd, BTRFS_IOC_INO_LOOKUP, &ino_args) < 0) |
| return -errno; |
| |
| if (!made_writable) { |
| r = btrfs_subvol_set_read_only_fd(subvol_fd, false); |
| if (r < 0) |
| return r; |
| |
| made_writable = true; |
| } |
| |
| if (isempty(ino_args.name)) |
| /* Subvolume is in the top-level |
| * directory of the subvolume. */ |
| r = subvol_remove_children(subvol_fd, p, sh->objectid, flags); |
| else { |
| _cleanup_close_ int child_fd = -EBADF; |
| |
| /* Subvolume is somewhere further down, |
| * hence we need to open the |
| * containing directory first */ |
| |
| child_fd = openat(subvol_fd, ino_args.name, O_RDONLY|O_NOCTTY|O_CLOEXEC|O_DIRECTORY|O_NOFOLLOW); |
| if (child_fd < 0) |
| return -errno; |
| |
| r = subvol_remove_children(child_fd, p, sh->objectid, flags); |
| } |
| if (r < 0) |
| return r; |
| } |
| |
| /* Increase search key by one, to read the next item, if we can. */ |
| if (!btrfs_ioctl_search_args_inc(&args)) |
| break; |
| } |
| |
| /* OK, the child subvolumes should all be gone now, let's try |
| * again to remove the subvolume */ |
| if (ioctl(fd, BTRFS_IOC_SNAP_DESTROY, &vol_args) < 0) |
| return -errno; |
| |
| (void) btrfs_qgroup_destroy_recursive(fd, subvol_id); |
| return 0; |
| } |
| |
| int btrfs_subvol_remove(const char *path, BtrfsRemoveFlags flags) { |
| _cleanup_free_ char *subvolume = NULL; |
| _cleanup_close_ int fd = -EBADF; |
| int r; |
| |
| assert(path); |
| |
| r = extract_subvolume_name(path, &subvolume); |
| if (r < 0) |
| return r; |
| |
| fd = open_parent(path, O_CLOEXEC, 0); |
| if (fd < 0) |
| return fd; |
| |
| return subvol_remove_children(fd, subvolume, 0, flags); |
| } |
| |
| int btrfs_subvol_remove_fd(int fd, const char *subvolume, BtrfsRemoveFlags flags) { |
| return subvol_remove_children(fd, subvolume, 0, flags); |
| } |
| |
| int btrfs_qgroup_copy_limits(int fd, uint64_t old_qgroupid, uint64_t new_qgroupid) { |
| |
| struct btrfs_ioctl_search_args args = { |
| /* Tree of quota items */ |
| .key.tree_id = BTRFS_QUOTA_TREE_OBJECTID, |
| |
| /* The object ID is always 0 */ |
| .key.min_objectid = 0, |
| .key.max_objectid = 0, |
| |
| /* Look precisely for the quota items */ |
| .key.min_type = BTRFS_QGROUP_LIMIT_KEY, |
| .key.max_type = BTRFS_QGROUP_LIMIT_KEY, |
| |
| /* For our qgroup */ |
| .key.min_offset = old_qgroupid, |
| .key.max_offset = old_qgroupid, |
| |
| /* No restrictions on the other components */ |
| .key.min_transid = 0, |
| .key.max_transid = UINT64_MAX, |
| }; |
| |
| int r; |
| |
| r = fd_is_fs_type(fd, BTRFS_SUPER_MAGIC); |
| if (r < 0) |
| return r; |
| if (!r) |
| return -ENOTTY; |
| |
| while (btrfs_ioctl_search_args_compare(&args) <= 0) { |
| const struct btrfs_ioctl_search_header *sh; |
| unsigned i; |
| |
| args.key.nr_items = 256; |
| if (ioctl(fd, BTRFS_IOC_TREE_SEARCH, &args) < 0) { |
| if (errno == ENOENT) /* quota tree missing: quota is not enabled, hence nothing to copy */ |
| break; |
| |
| return -errno; |
| } |
| |
| if (args.key.nr_items <= 0) |
| break; |
| |
| FOREACH_BTRFS_IOCTL_SEARCH_HEADER(i, sh, args) { |
| const struct btrfs_qgroup_limit_item *qli = BTRFS_IOCTL_SEARCH_HEADER_BODY(sh); |
| struct btrfs_ioctl_qgroup_limit_args qargs; |
| unsigned c; |
| |
| /* Make sure we start the next search at least from this entry */ |
| btrfs_ioctl_search_args_set(&args, sh); |
| |
| if (sh->objectid != 0) |
| continue; |
| if (sh->type != BTRFS_QGROUP_LIMIT_KEY) |
| continue; |
| if (sh->offset != old_qgroupid) |
| continue; |
| |
| /* We found the entry, now copy things over. */ |
| |
| qargs = (struct btrfs_ioctl_qgroup_limit_args) { |
| .qgroupid = new_qgroupid, |
| |
| .lim.max_rfer = le64toh(qli->max_rfer), |
| .lim.max_excl = le64toh(qli->max_excl), |
| .lim.rsv_rfer = le64toh(qli->rsv_rfer), |
| .lim.rsv_excl = le64toh(qli->rsv_excl), |
| |
| .lim.flags = le64toh(qli->flags) & (BTRFS_QGROUP_LIMIT_MAX_RFER| |
| BTRFS_QGROUP_LIMIT_MAX_EXCL| |
| BTRFS_QGROUP_LIMIT_RSV_RFER| |
| BTRFS_QGROUP_LIMIT_RSV_EXCL), |
| }; |
| |
| for (c = 0;; c++) { |
| if (ioctl(fd, BTRFS_IOC_QGROUP_LIMIT, &qargs) < 0) { |
| if (errno == EBUSY && c < 10) { |
| (void) btrfs_quota_scan_wait(fd); |
| continue; |
| } |
| return -errno; |
| } |
| |
| break; |
| } |
| |
| return 1; |
| } |
| |
| /* Increase search key by one, to read the next item, if we can. */ |
| if (!btrfs_ioctl_search_args_inc(&args)) |
| break; |
| } |
| |
| return 0; |
| } |
| |
| static int copy_quota_hierarchy(int fd, uint64_t old_subvol_id, uint64_t new_subvol_id) { |
| _cleanup_free_ uint64_t *old_qgroups = NULL, *old_parent_qgroups = NULL; |
| bool copy_from_parent = false, insert_intermediary_qgroup = false; |
| int n_old_qgroups, n_old_parent_qgroups, r; |
| uint64_t old_parent_id; |
| |
| assert(fd >= 0); |
| |
| /* Copies a reduced form of quota information from the old to |
| * the new subvolume. */ |
| |
| n_old_qgroups = btrfs_qgroup_find_parents(fd, old_subvol_id, &old_qgroups); |
| if (n_old_qgroups <= 0) /* Nothing to copy */ |
| return n_old_qgroups; |
| |
| r = btrfs_subvol_get_parent(fd, old_subvol_id, &old_parent_id); |
| if (r == -ENXIO) |
| /* We have no parent, hence nothing to copy. */ |
| n_old_parent_qgroups = 0; |
| else if (r < 0) |
| return r; |
| else { |
| n_old_parent_qgroups = btrfs_qgroup_find_parents(fd, old_parent_id, &old_parent_qgroups); |
| if (n_old_parent_qgroups < 0) |
| return n_old_parent_qgroups; |
| } |
| |
| for (int i = 0; i < n_old_qgroups; i++) { |
| uint64_t id; |
| |
| r = btrfs_qgroupid_split(old_qgroups[i], NULL, &id); |
| if (r < 0) |
| return r; |
| |
| if (id == old_subvol_id) { |
| /* The old subvolume was member of a qgroup |
| * that had the same id, but a different level |
| * as it self. Let's set up something similar |
| * in the destination. */ |
| insert_intermediary_qgroup = true; |
| break; |
| } |
| |
| for (int j = 0; j < n_old_parent_qgroups; j++) |
| if (old_parent_qgroups[j] == old_qgroups[i]) |
| /* The old subvolume shared a common |
| * parent qgroup with its parent |
| * subvolume. Let's set up something |
| * similar in the destination. */ |
| copy_from_parent = true; |
| } |
| |
| if (!insert_intermediary_qgroup && !copy_from_parent) |
| return 0; |
| |
| return btrfs_subvol_auto_qgroup_fd(fd, new_subvol_id, insert_intermediary_qgroup); |
| } |
| |
| static int copy_subtree_quota_limits(int fd, uint64_t old_subvol, uint64_t new_subvol) { |
| uint64_t old_subtree_qgroup, new_subtree_qgroup; |
| bool changed; |
| int r; |
| |
| /* First copy the leaf limits */ |
| r = btrfs_qgroup_copy_limits(fd, old_subvol, new_subvol); |
| if (r < 0) |
| return r; |
| changed = r > 0; |
| |
| /* Then, try to copy the subtree limits, if there are any. */ |
| r = btrfs_subvol_find_subtree_qgroup(fd, old_subvol, &old_subtree_qgroup); |
| if (r < 0) |
| return r; |
| if (r == 0) |
| return changed; |
| |
| r = btrfs_subvol_find_subtree_qgroup(fd, new_subvol, &new_subtree_qgroup); |
| if (r < 0) |
| return r; |
| if (r == 0) |
| return changed; |
| |
| r = btrfs_qgroup_copy_limits(fd, old_subtree_qgroup, new_subtree_qgroup); |
| if (r != 0) |
| return r; |
| |
| return changed; |
| } |
| |
| static int subvol_snapshot_children( |
| int old_fd, |
| int new_fd, |
| const char *subvolume, |
| uint64_t old_subvol_id, |
| BtrfsSnapshotFlags flags) { |
| |
| struct btrfs_ioctl_search_args args = { |
| .key.tree_id = BTRFS_ROOT_TREE_OBJECTID, |
| |
| .key.min_objectid = BTRFS_FIRST_FREE_OBJECTID, |
| .key.max_objectid = BTRFS_LAST_FREE_OBJECTID, |
| |
| .key.min_type = BTRFS_ROOT_BACKREF_KEY, |
| .key.max_type = BTRFS_ROOT_BACKREF_KEY, |
| |
| .key.min_transid = 0, |
| .key.max_transid = UINT64_MAX, |
| }; |
| |
| struct btrfs_ioctl_vol_args_v2 vol_args = { |
| .flags = flags & BTRFS_SNAPSHOT_READ_ONLY ? BTRFS_SUBVOL_RDONLY : 0, |
| .fd = old_fd, |
| }; |
| _cleanup_close_ int subvolume_fd = -EBADF; |
| uint64_t new_subvol_id; |
| int r; |
| |
| assert(old_fd >= 0); |
| assert(new_fd >= 0); |
| assert(subvolume); |
| |
| strncpy(vol_args.name, subvolume, sizeof(vol_args.name)-1); |
| |
| if (ioctl(new_fd, BTRFS_IOC_SNAP_CREATE_V2, &vol_args) < 0) |
| return -errno; |
| |
| if (!(flags & BTRFS_SNAPSHOT_RECURSIVE) && |
| !(flags & BTRFS_SNAPSHOT_QUOTA)) |
| return 0; |
| |
| if (old_subvol_id == 0) { |
| r = btrfs_subvol_get_id_fd(old_fd, &old_subvol_id); |
| if (r < 0) |
| return r; |
| } |
| |
| r = btrfs_subvol_get_id(new_fd, vol_args.name, &new_subvol_id); |
| if (r < 0) |
| return r; |
| |
| if (flags & BTRFS_SNAPSHOT_QUOTA) |
| (void) copy_quota_hierarchy(new_fd, old_subvol_id, new_subvol_id); |
| |
| if (!(flags & BTRFS_SNAPSHOT_RECURSIVE)) { |
| |
| if (flags & BTRFS_SNAPSHOT_QUOTA) |
| (void) copy_subtree_quota_limits(new_fd, old_subvol_id, new_subvol_id); |
| |
| return 0; |
| } |
| |
| args.key.min_offset = args.key.max_offset = old_subvol_id; |
| |
| while (btrfs_ioctl_search_args_compare(&args) <= 0) { |
| const struct btrfs_ioctl_search_header *sh; |
| unsigned i; |
| |
| args.key.nr_items = 256; |
| if (ioctl(old_fd, BTRFS_IOC_TREE_SEARCH, &args) < 0) |
| return -errno; |
| |
| if (args.key.nr_items <= 0) |
| break; |
| |
| FOREACH_BTRFS_IOCTL_SEARCH_HEADER(i, sh, args) { |
| _cleanup_free_ char *p = NULL, *c = NULL, *np = NULL; |
| const struct btrfs_root_ref *ref; |
| _cleanup_close_ int old_child_fd = -EBADF, new_child_fd = -EBADF; |
| |
| btrfs_ioctl_search_args_set(&args, sh); |
| |
| if (sh->type != BTRFS_ROOT_BACKREF_KEY) |
| continue; |
| |
| /* Avoid finding the source subvolume a second |
| * time */ |
| if (sh->offset != old_subvol_id) |
| continue; |
| |
| /* Avoid running into loops if the new |
| * subvolume is below the old one. */ |
| if (sh->objectid == new_subvol_id) |
| continue; |
| |
| ref = BTRFS_IOCTL_SEARCH_HEADER_BODY(sh); |
| p = strndup((char*) ref + sizeof(struct btrfs_root_ref), le64toh(ref->name_len)); |
| if (!p) |
| return -ENOMEM; |
| |
| struct btrfs_ioctl_ino_lookup_args ino_args = { |
| .treeid = old_subvol_id, |
| .objectid = htole64(ref->dirid), |
| }; |
| |
| if (ioctl(old_fd, BTRFS_IOC_INO_LOOKUP, &ino_args) < 0) |
| return -errno; |
| |
| c = path_join(ino_args.name, p); |
| if (!c) |
| return -ENOMEM; |
| |
| old_child_fd = openat(old_fd, c, O_RDONLY|O_NOCTTY|O_CLOEXEC|O_DIRECTORY|O_NOFOLLOW); |
| if (old_child_fd < 0) |
| return -errno; |
| |
| np = path_join(subvolume, ino_args.name); |
| if (!np) |
| return -ENOMEM; |
| |
| new_child_fd = openat(new_fd, np, O_RDONLY|O_NOCTTY|O_CLOEXEC|O_DIRECTORY|O_NOFOLLOW); |
| if (new_child_fd < 0) |
| return -errno; |
| |
| if (flags & BTRFS_SNAPSHOT_READ_ONLY) { |
| /* If the snapshot is read-only we |
| * need to mark it writable |
| * temporarily, to put the subsnapshot |
| * into place. */ |
| |
| if (subvolume_fd < 0) { |
| subvolume_fd = openat(new_fd, subvolume, O_RDONLY|O_NOCTTY|O_CLOEXEC|O_DIRECTORY|O_NOFOLLOW); |
| if (subvolume_fd < 0) |
| return -errno; |
| } |
| |
| r = btrfs_subvol_set_read_only_fd(subvolume_fd, false); |
| if (r < 0) |
| return r; |
| } |
| |
| /* When btrfs clones the subvolumes, child |
| * subvolumes appear as empty directories. Remove |
| * them, so that we can create a new snapshot |
| * in their place */ |
| if (unlinkat(new_child_fd, p, AT_REMOVEDIR) < 0) { |
| int k = -errno; |
| |
| if (flags & BTRFS_SNAPSHOT_READ_ONLY) |
| (void) btrfs_subvol_set_read_only_fd(subvolume_fd, true); |
| |
| return k; |
| } |
| |
| r = subvol_snapshot_children(old_child_fd, new_child_fd, p, sh->objectid, flags & ~BTRFS_SNAPSHOT_FALLBACK_COPY); |
| |
| /* Restore the readonly flag */ |
| if (flags & BTRFS_SNAPSHOT_READ_ONLY) { |
| int k; |
| |
| k = btrfs_subvol_set_read_only_fd(subvolume_fd, true); |
| if (r >= 0 && k < 0) |
| return k; |
| } |
| |
| if (r < 0) |
| return r; |
| } |
| |
| /* Increase search key by one, to read the next item, if we can. */ |
| if (!btrfs_ioctl_search_args_inc(&args)) |
| break; |
| } |
| |
| if (flags & BTRFS_SNAPSHOT_QUOTA) |
| (void) copy_subtree_quota_limits(new_fd, old_subvol_id, new_subvol_id); |
| |
| return 0; |
| } |
| |
| int btrfs_subvol_snapshot_fd_full( |
| int old_fd, |
| const char *new_path, |
| BtrfsSnapshotFlags flags, |
| copy_progress_path_t progress_path, |
| copy_progress_bytes_t progress_bytes, |
| void *userdata) { |
| |
| _cleanup_free_ char *subvolume = NULL; |
| _cleanup_close_ int new_fd = -EBADF; |
| int r; |
| |
| assert(old_fd >= 0); |
| assert(new_path); |
| |
| r = btrfs_is_subvol_fd(old_fd); |
| if (r < 0) |
| return r; |
| if (r == 0) { |
| bool plain_directory = false; |
| |
| /* If the source isn't a proper subvolume, fail unless fallback is requested */ |
| if (!(flags & BTRFS_SNAPSHOT_FALLBACK_COPY)) |
| return -EISDIR; |
| |
| r = btrfs_subvol_make(new_path); |
| if (ERRNO_IS_NOT_SUPPORTED(r) && (flags & BTRFS_SNAPSHOT_FALLBACK_DIRECTORY)) { |
| /* If the destination doesn't support subvolumes, then use a plain directory, if that's requested. */ |
| if (mkdir(new_path, 0755) < 0) |
| return -errno; |
| |
| plain_directory = true; |
| } else if (r < 0) |
| return r; |
| |
| r = copy_directory_fd_full( |
| old_fd, new_path, |
| COPY_MERGE_EMPTY| |
| COPY_REFLINK| |
| COPY_SAME_MOUNT| |
| COPY_HARDLINKS| |
| COPY_ALL_XATTRS| |
| (FLAGS_SET(flags, BTRFS_SNAPSHOT_SIGINT) ? COPY_SIGINT : 0)| |
| (FLAGS_SET(flags, BTRFS_SNAPSHOT_SIGTERM) ? COPY_SIGTERM : 0), |
| progress_path, |
| progress_bytes, |
| userdata); |
| if (r < 0) |
| goto fallback_fail; |
| |
| if (flags & BTRFS_SNAPSHOT_READ_ONLY) { |
| |
| if (plain_directory) { |
| /* Plain directories have no recursive read-only flag, but something pretty close to |
| * it: the IMMUTABLE bit. Let's use this here, if this is requested. */ |
| |
| if (flags & BTRFS_SNAPSHOT_FALLBACK_IMMUTABLE) |
| (void) chattr_path(new_path, FS_IMMUTABLE_FL, FS_IMMUTABLE_FL, NULL); |
| } else { |
| r = btrfs_subvol_set_read_only(new_path, true); |
| if (r < 0) |
| goto fallback_fail; |
| } |
| } |
| |
| return 0; |
| |
| fallback_fail: |
| (void) rm_rf(new_path, REMOVE_ROOT|REMOVE_PHYSICAL|REMOVE_SUBVOLUME); |
| return r; |
| } |
| |
| r = extract_subvolume_name(new_path, &subvolume); |
| if (r < 0) |
| return r; |
| |
| new_fd = open_parent(new_path, O_CLOEXEC, 0); |
| if (new_fd < 0) |
| return new_fd; |
| |
| return subvol_snapshot_children(old_fd, new_fd, subvolume, 0, flags); |
| } |
| |
| int btrfs_subvol_snapshot_full( |
| const char *old_path, |
| const char *new_path, |
| BtrfsSnapshotFlags flags, |
| copy_progress_path_t progress_path, |
| copy_progress_bytes_t progress_bytes, |
| void *userdata) { |
| |
| _cleanup_close_ int old_fd = -EBADF; |
| |
| assert(old_path); |
| assert(new_path); |
| |
| old_fd = open(old_path, O_RDONLY|O_NOCTTY|O_CLOEXEC|O_DIRECTORY); |
| if (old_fd < 0) |
| return -errno; |
| |
| return btrfs_subvol_snapshot_fd_full(old_fd, new_path, flags, progress_path, progress_bytes, userdata); |
| } |
| |
| int btrfs_qgroup_find_parents(int fd, uint64_t qgroupid, uint64_t **ret) { |
| |
| struct btrfs_ioctl_search_args args = { |
| /* Tree of quota items */ |
| .key.tree_id = BTRFS_QUOTA_TREE_OBJECTID, |
| |
| /* Look precisely for the quota relation items */ |
| .key.min_type = BTRFS_QGROUP_RELATION_KEY, |
| .key.max_type = BTRFS_QGROUP_RELATION_KEY, |
| |
| /* No restrictions on the other components */ |
| .key.min_offset = 0, |
| .key.max_offset = UINT64_MAX, |
| |
| .key.min_transid = 0, |
| .key.max_transid = UINT64_MAX, |
| }; |
| |
| _cleanup_free_ uint64_t *items = NULL; |
| size_t n_items = 0; |
| int r; |
| |
| assert(fd >= 0); |
| assert(ret); |
| |
| if (qgroupid == 0) { |
| r = btrfs_subvol_get_id_fd(fd, &qgroupid); |
| if (r < 0) |
| return r; |
| } else { |
| r = fd_is_fs_type(fd, BTRFS_SUPER_MAGIC); |
| if (r < 0) |
| return r; |
| if (!r) |
| return -ENOTTY; |
| } |
| |
| args.key.min_objectid = args.key.max_objectid = qgroupid; |
| |
| while (btrfs_ioctl_search_args_compare(&args) <= 0) { |
| const struct btrfs_ioctl_search_header *sh; |
| unsigned i; |
| |
| args.key.nr_items = 256; |
| if (ioctl(fd, BTRFS_IOC_TREE_SEARCH, &args) < 0) { |
| if (errno == ENOENT) /* quota tree missing: quota is disabled */ |
| break; |
| |
| return -errno; |
| } |
| |
| if (args.key.nr_items <= 0) |
| break; |
| |
| FOREACH_BTRFS_IOCTL_SEARCH_HEADER(i, sh, args) { |
| |
| /* Make sure we start the next search at least from this entry */ |
| btrfs_ioctl_search_args_set(&args, sh); |
| |
| if (sh->type != BTRFS_QGROUP_RELATION_KEY) |
| continue; |
| if (sh->offset < sh->objectid) |
| continue; |
| if (sh->objectid != qgroupid) |
| continue; |
| |
| if (!GREEDY_REALLOC(items, n_items+1)) |
| return -ENOMEM; |
| |
| items[n_items++] = sh->offset; |
| } |
| |
| /* Increase search key by one, to read the next item, if we can. */ |
| if (!btrfs_ioctl_search_args_inc(&args)) |
| break; |
| } |
| |
| if (n_items <= 0) { |
| *ret = NULL; |
| return 0; |
| } |
| |
| *ret = TAKE_PTR(items); |
| |
| return (int) n_items; |
| } |
| |
| int btrfs_subvol_auto_qgroup_fd(int fd, uint64_t subvol_id, bool insert_intermediary_qgroup) { |
| _cleanup_free_ uint64_t *qgroups = NULL; |
| _cleanup_close_ int real_fd = -EBADF; |
| uint64_t parent_subvol; |
| bool changed = false; |
| int n = 0, r; |
| |
| assert(fd >= 0); |
| |
| /* |
| * Sets up the specified subvolume's qgroup automatically in |
| * one of two ways: |
| * |
| * If insert_intermediary_qgroup is false, the subvolume's |
| * leaf qgroup will be assigned to the same parent qgroups as |
| * the subvolume's parent subvolume. |
| * |
| * If insert_intermediary_qgroup is true a new intermediary |
| * higher-level qgroup is created, with a higher level number, |
| * but reusing the id of the subvolume. The level number is |
| * picked as one smaller than the lowest level qgroup the |
| * parent subvolume is a member of. If the parent subvolume's |
| * leaf qgroup is assigned to no higher-level qgroup a new |
| * qgroup of level 255 is created instead. Either way, the new |
| * qgroup is then assigned to the parent's higher-level |
| * qgroup, and the subvolume itself is assigned to it. |
| * |
| * If the subvolume is already assigned to a higher level |
| * qgroup, no operation is executed. |
| * |
| * Effectively this means: regardless if |
| * insert_intermediary_qgroup is true or not, after this |
| * function is invoked the subvolume will be accounted within |
| * the same qgroups as the parent. However, if it is true, it |
| * will also get its own higher-level qgroup, which may in |
| * turn be used by subvolumes created beneath this subvolume |
| * later on. |
| * |
| * This hence defines a simple default qgroup setup for |
| * subvolumes, as long as this function is invoked on each |
| * created subvolume: each subvolume is always accounting |
| * together with its immediate parents. Optionally, if |
| * insert_intermediary_qgroup is true, it will also get a |
| * qgroup that then includes all its own child subvolumes. |
| */ |
| |
| /* Turn this into a proper fd, if it is currently O_PATH */ |
| fd = fd_reopen_condition(fd, O_RDONLY|O_CLOEXEC, O_PATH, &real_fd); |
| if (fd < 0) |
| return fd; |
| |
| if (subvol_id == 0) { |
| r = btrfs_is_subvol_fd(fd); |
| if (r < 0) |
| return r; |
| if (!r) |
| return -ENOTTY; |
| |
| r = btrfs_subvol_get_id_fd(fd, &subvol_id); |
| if (r < 0) |
| return r; |
| } |
| |
| n = btrfs_qgroup_find_parents(fd, subvol_id, &qgroups); |
| if (n < 0) |
| return n; |
| if (n > 0) /* already parent qgroups set up, let's bail */ |
| return 0; |
| |
| qgroups = mfree(qgroups); |
| |
| r = btrfs_subvol_get_parent(fd, subvol_id, &parent_subvol); |
| if (r == -ENXIO) |
| /* No parent, hence no qgroup memberships */ |
| n = 0; |
| else if (r < 0) |
| return r; |
| else { |
| n = btrfs_qgroup_find_parents(fd, parent_subvol, &qgroups); |
| if (n < 0) |
| return n; |
| } |
| |
| if (insert_intermediary_qgroup) { |
| uint64_t lowest = 256, new_qgroupid; |
| bool created = false; |
| |
| /* Determine the lowest qgroup that the parent |
| * subvolume is assigned to. */ |
| |
| for (int i = 0; i < n; i++) { |
| uint64_t level; |
| |
| r = btrfs_qgroupid_split(qgroups[i], &level, NULL); |
| if (r < 0) |
| return r; |
| |
| if (level < lowest) |
| lowest = level; |
| } |
| |
| if (lowest <= 1) /* There are no levels left we could use insert an intermediary qgroup at */ |
| return -EBUSY; |
| |
| r = btrfs_qgroupid_make(lowest - 1, subvol_id, &new_qgroupid); |
| if (r < 0) |
| return r; |
| |
| /* Create the new intermediary group, unless it already exists */ |
| r = btrfs_qgroup_create(fd, new_qgroupid); |
| if (r < 0 && r != -EEXIST) |
| return r; |
| if (r >= 0) |
| changed = created = true; |
| |
| for (int i = 0; i < n; i++) { |
| r = btrfs_qgroup_assign(fd, new_qgroupid, qgroups[i]); |
| if (r < 0 && r != -EEXIST) { |
| if (created) |
| (void) btrfs_qgroup_destroy_recursive(fd, new_qgroupid); |
| |
| return r; |
| } |
| if (r >= 0) |
| changed = true; |
| } |
| |
| r = btrfs_qgroup_assign(fd, subvol_id, new_qgroupid); |
| if (r < 0 && r != -EEXIST) { |
| if (created) |
| (void) btrfs_qgroup_destroy_recursive(fd, new_qgroupid); |
| return r; |
| } |
| if (r >= 0) |
| changed = true; |
| |
| } else { |
| int i; |
| |
| /* Assign our subvolume to all the same qgroups as the parent */ |
| |
| for (i = 0; i < n; i++) { |
| r = btrfs_qgroup_assign(fd, subvol_id, qgroups[i]); |
| if (r < 0 && r != -EEXIST) |
| return r; |
| if (r >= 0) |
| changed = true; |
| } |
| } |
| |
| return changed; |
| } |
| |
| int btrfs_subvol_auto_qgroup(const char *path, uint64_t subvol_id, bool create_intermediary_qgroup) { |
| _cleanup_close_ int fd = -EBADF; |
| |
| fd = open(path, O_RDONLY|O_NOCTTY|O_CLOEXEC|O_DIRECTORY); |
| if (fd < 0) |
| return -errno; |
| |
| return btrfs_subvol_auto_qgroup_fd(fd, subvol_id, create_intermediary_qgroup); |
| } |
| |
| int btrfs_subvol_get_parent(int fd, uint64_t subvol_id, uint64_t *ret) { |
| |
| struct btrfs_ioctl_search_args args = { |
| /* Tree of tree roots */ |
| .key.tree_id = BTRFS_ROOT_TREE_OBJECTID, |
| |
| /* Look precisely for the subvolume items */ |
| .key.min_type = BTRFS_ROOT_BACKREF_KEY, |
| .key.max_type = BTRFS_ROOT_BACKREF_KEY, |
| |
| /* No restrictions on the other components */ |
| .key.min_offset = 0, |
| .key.max_offset = UINT64_MAX, |
| |
| .key.min_transid = 0, |
| .key.max_transid = UINT64_MAX, |
| }; |
| int r; |
| |
| assert(fd >= 0); |
| assert(ret); |
| |
| if (subvol_id == 0) { |
| r = btrfs_subvol_get_id_fd(fd, &subvol_id); |
| if (r < 0) |
| return r; |
| } else { |
| r = fd_is_fs_type(fd, BTRFS_SUPER_MAGIC); |
| if (r < 0) |
| return r; |
| if (!r) |
| return -ENOTTY; |
| } |
| |
| args.key.min_objectid = args.key.max_objectid = subvol_id; |
| |
| while (btrfs_ioctl_search_args_compare(&args) <= 0) { |
| const struct btrfs_ioctl_search_header *sh; |
| unsigned i; |
| |
| args.key.nr_items = 256; |
| if (ioctl(fd, BTRFS_IOC_TREE_SEARCH, &args) < 0) |
| return negative_errno(); |
| |
| if (args.key.nr_items <= 0) |
| break; |
| |
| FOREACH_BTRFS_IOCTL_SEARCH_HEADER(i, sh, args) { |
| |
| if (sh->type != BTRFS_ROOT_BACKREF_KEY) |
| continue; |
| if (sh->objectid != subvol_id) |
| continue; |
| |
| *ret = sh->offset; |
| return 0; |
| } |
| } |
| |
| return -ENXIO; |
| } |
| |
| int btrfs_forget_device(const char *path) { |
| _cleanup_close_ int control_fd = -EBADF; |
| struct btrfs_ioctl_vol_args args = {}; |
| |
| assert(path); |
| |
| if (strlen(path) > BTRFS_PATH_NAME_MAX) |
| return -E2BIG; |
| |
| strcpy(args.name, path); |
| |
| control_fd = open("/dev/btrfs-control", O_RDWR|O_CLOEXEC); |
| if (control_fd < 0) |
| return -errno; |
| |
| return RET_NERRNO(ioctl(control_fd, BTRFS_IOC_FORGET_DEV, &args)); |
| } |
