picnoir
/
Systemd
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

btrfs: support recursively removing btrfs snapshots

This commit is contained in:
Lennart Poettering 2015-04-06 10:57:17 +02:00
parent 41d1ed059b
commit d9e2daaf3d
17 changed files with 239 additions and 70 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

9
Makefile.am
View File

@ -771,8 +771,6 @@ libsystemd_shared_la_SOURCES = \
src/shared/device-nodes.h \
src/shared/util.c \
src/shared/util.h \
src/shared/rm-rf.c \
src/shared/rm-rf.h \
src/shared/virt.c \
src/shared/virt.h \
src/shared/architecture.c \
@ -980,6 +978,8 @@ libsystemd_label_la_SOURCES = \
src/shared/btrfs-util.c \
src/shared/btrfs-util.h \
src/shared/btrfs-ctree.h \
src/shared/rm-rf.c \
src/shared/rm-rf.h \
src/shared/machine-image.c \
src/shared/machine-image.h \
src/shared/machine-pool.c \
@ -1660,6 +1660,7 @@ test_util_SOURCES = \
src/test/test-util.c
test_util_LDADD = \
libsystemd-label.la \
libsystemd-shared.la
test_path_lookup_SOURCES = \
@ -1668,6 +1669,7 @@ test_path_lookup_SOURCES = \
test_path_lookup_LDADD = \
-lm \
libsystemd-units.la \
libsystemd-label.la \
libsystemd-shared.la
test_uid_range_SOURCES = \
@ -1967,6 +1969,7 @@ test_path_util_SOURCES = \
src/test/test-path-util.c
test_path_util_LDADD = \
libsystemd-label.la \
libsystemd-shared.la
test_path_SOURCES = \
@ -2026,6 +2029,7 @@ test_conf_files_SOURCES = \
src/test/test-conf-files.c
test_conf_files_LDADD = \
libsystemd-label.la \
libsystemd-shared.la
test_bus_policy_SOURCES = \
@ -2501,6 +2505,7 @@ bootctl_CFLAGS = \
$(BLKID_CFLAGS)
bootctl_LDADD = \
libsystemd-label.la \
libsystemd-shared.la \
libsystemd-internal.la \
$(BLKID_LIBS)

2
src/import/export-tar.c
View File

@ -77,7 +77,7 @@ TarExport *tar_export_unref(TarExport *e) {
}
if (e->temp_path) {
(void) btrfs_subvol_remove(e->temp_path);
(void) btrfs_subvol_remove(e->temp_path, false);
free(e->temp_path);
}

6
src/import/import-raw.c
View File

@ -241,10 +241,8 @@ static int raw_import_finish(RawImport *i) {
return r;
}
if (i->force_local) {
(void) btrfs_subvol_remove(i->final_path);
(void) rm_rf(i->final_path, REMOVE_ROOT|REMOVE_PHYSICAL);
}
if (i->force_local)
(void) rm_rf(i->final_path, REMOVE_ROOT|REMOVE_PHYSICAL|REMOVE_SUBVOLUME);
r = rename_noreplace(AT_FDCWD, i->temp_path, AT_FDCWD, i->final_path);
if (r < 0)

9
src/import/import-tar.c
View File

@ -87,8 +87,7 @@ TarImport* tar_import_unref(TarImport *i) {
}
if (i->temp_path) {
(void) btrfs_subvol_remove(i->temp_path);
(void) rm_rf(i->temp_path, REMOVE_ROOT|REMOVE_PHYSICAL);
(void) rm_rf(i->temp_path, REMOVE_ROOT|REMOVE_PHYSICAL|REMOVE_SUBVOLUME);
free(i->temp_path);
}
@ -197,10 +196,8 @@ static int tar_import_finish(TarImport *i) {
return r;
}
if (i->force_local) {
(void) btrfs_subvol_remove(i->final_path);
(void) rm_rf(i->final_path, REMOVE_ROOT|REMOVE_PHYSICAL);
}
if (i->force_local)
(void) rm_rf(i->final_path, REMOVE_ROOT|REMOVE_PHYSICAL|REMOVE_SUBVOLUME);
r = rename_noreplace(AT_FDCWD, i->temp_path, AT_FDCWD, i->final_path);
if (r < 0)

6
src/import/pull-common.c
View File

@ -124,10 +124,8 @@ int pull_make_local_copy(const char *final, const char *image_root, const char *
p = strjoina(image_root, "/", local);
if (force_local) {
(void) btrfs_subvol_remove(p);
(void) rm_rf(p, REMOVE_ROOT|REMOVE_PHYSICAL);
}
if (force_local)
(void) rm_rf(p, REMOVE_ROOT|REMOVE_PHYSICAL|REMOVE_SUBVOLUME);
r = btrfs_subvol_snapshot(final, p, false, false);
if (r == -ENOTTY) {

3
src/import/pull-dkr.c
View File

@ -111,8 +111,7 @@ DkrPull* dkr_pull_unref(DkrPull *i) {
sd_event_unref(i->event);
if (i->temp_path) {
(void) btrfs_subvol_remove(i->temp_path);
(void) rm_rf(i->temp_path, REMOVE_ROOT|REMOVE_PHYSICAL);
(void) rm_rf(i->temp_path, REMOVE_ROOT|REMOVE_PHYSICAL|REMOVE_SUBVOLUME);
free(i->temp_path);
}

6
src/import/pull-raw.c
View File

@ -277,10 +277,8 @@ static int raw_pull_make_local_copy(RawPull *i) {
p = strjoina(i->image_root, "/", i->local, ".raw");
if (i->force_local) {
(void) btrfs_subvol_remove(p);
(void) rm_rf(p, REMOVE_ROOT|REMOVE_PHYSICAL);
}
if (i->force_local)
(void) rm_rf(p, REMOVE_ROOT|REMOVE_PHYSICAL|REMOVE_SUBVOLUME);
r = tempfn_random(p, &tp);
if (r < 0)

3
src/import/pull-tar.c
View File

@ -88,8 +88,7 @@ TarPull* tar_pull_unref(TarPull *i) {
sd_event_unref(i->event);
if (i->temp_path) {
(void) btrfs_subvol_remove(i->temp_path);
(void) rm_rf(i->temp_path, REMOVE_ROOT|REMOVE_PHYSICAL);
(void) rm_rf(i->temp_path, REMOVE_ROOT|REMOVE_PHYSICAL|REMOVE_SUBVOLUME);
free(i->temp_path);
}

2
src/nspawn/nspawn.c
View File

@ -4459,7 +4459,7 @@ finish:
if (remove_subvol && arg_directory) {
int k;
k = btrfs_subvol_remove(arg_directory);
k = btrfs_subvol_remove(arg_directory, true);
if (k < 0)
log_warning_errno(k, "Cannot remove subvolume '%s', ignoring: %m", arg_directory);
}

6
src/shared/btrfs-ctree.h
View File

@ -90,3 +90,9 @@ struct btrfs_qgroup_limit_item {
le64_t rsv_rfer;
le64_t rsv_excl;
} _packed_;
struct btrfs_root_ref {
le64_t dirid;
le64_t sequence;
le16_t name_len;
} _packed_;

163
src/shared/btrfs-util.c
View File

@ -124,14 +124,14 @@ int btrfs_subvol_snapshot_fd(int old_fd, const char *new_path, bool read_only, b
r = copy_directory_fd(old_fd, new_path, true);
if (r < 0) {
btrfs_subvol_remove(new_path);
btrfs_subvol_remove(new_path, false);
return r;
}
if (read_only) {
r = btrfs_subvol_set_read_only(new_path, true);
if (r < 0) {
btrfs_subvol_remove(new_path);
btrfs_subvol_remove(new_path, false);
return r;
}
}
@ -211,30 +211,6 @@ int btrfs_subvol_make_label(const char *path) {
return mac_smack_fix(path, false, false);
}
int btrfs_subvol_remove(const char *path) {
struct btrfs_ioctl_vol_args args = {};
_cleanup_close_ int fd = -1;
const char *subvolume;
int r;
assert(path);
r = extract_subvolume_name(path, &subvolume);
if (r < 0)
return r;
fd = open_parent(path, O_RDONLY|O_NOCTTY|O_CLOEXEC|O_DIRECTORY);
if (fd < 0)
return fd;
strncpy(args.name, subvolume, sizeof(args.name)-1);
if (ioctl(fd, BTRFS_IOC_SNAP_DESTROY, &args) < 0)
return -errno;
return 0;
}
int btrfs_subvol_set_read_only_fd(int fd, bool b) {
uint64_t flags, nflags;
struct stat st;
@ -798,3 +774,138 @@ int btrfs_resize_loopback(const char *p, uint64_t new_size, bool grow_only) {
return btrfs_resize_loopback_fd(fd, new_size, grow_only);
}
static int subvol_remove_children(int fd, const char *subvolume, uint64_t subvol_id, bool recursive) {
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_t) -1,
};
struct btrfs_ioctl_vol_args vol_args = {};
_cleanup_close_ int subvol_fd = -1;
int r;
assert(fd >= 0);
assert(subvolume);
/* 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)
return 0;
if (!recursive || errno != ENOTEMPTY)
return -errno;
/* OK, the subvolume is not empty, let's look for child
* subvolumes, and remove them, first */
subvol_fd = openat(fd, subvolume, O_RDONLY|O_NOCTTY|O_CLOEXEC|O_DIRECTORY);
if (subvol_fd < 0)
return -errno;
if (subvol_id == 0) {
r = btrfs_subvol_get_id_fd(subvol_fd, &subvol_id);
if (r < 0)
return r;
}
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;
struct btrfs_ioctl_ino_lookup_args ino_args;
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;
zero(ino_args);
ino_args.treeid = subvol_id;
ino_args.objectid = ref->dirid;
if (ioctl(fd, BTRFS_IOC_INO_LOOKUP, &ino_args) < 0)
return -errno;
if (isempty(ino_args.name))
/* Subvolume is in the top-level
* directory of the subvolume. */
r = subvol_remove_children(subvol_fd, p, sh->objectid, recursive);
else {
_cleanup_close_ int child_fd = -1;
/* 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);
if (child_fd < 0)
return -errno;
r = subvol_remove_children(child_fd, p, sh->objectid, recursive);
}
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;
return 0;
}
int btrfs_subvol_remove(const char *path, bool recursive) {
_cleanup_close_ int fd = -1;
const char *subvolume;
int r;
assert(path);
r = extract_subvolume_name(path, &subvolume);
if (r < 0)
return r;
fd = open_parent(path, O_RDONLY|O_NOCTTY|O_CLOEXEC|O_DIRECTORY);
if (fd < 0)
return fd;
return subvol_remove_children(fd, subvolume, 0, recursive);
}
int btrfs_subvol_remove_fd(int fd, const char *subvolume, bool recursive) {
return subvol_remove_children(fd, subvolume, 0, recursive);
}

4
src/shared/btrfs-util.h
View File

@ -47,7 +47,6 @@ int btrfs_is_snapshot(int fd);
int btrfs_subvol_make(const char *path);
int btrfs_subvol_make_label(const char *path);
int btrfs_subvol_remove(const char *path);
int btrfs_subvol_snapshot_fd(int old_fd, const char *new_path, bool read_only, bool fallback_copy);
int btrfs_subvol_snapshot(const char *old_path, const char *new_path, bool read_only, bool fallback_copy);
@ -76,3 +75,6 @@ int btrfs_quota_limit(const char *path, uint64_t referenced_max);
int btrfs_resize_loopback_fd(int fd, uint64_t size, bool grow_only);
int btrfs_resize_loopback(const char *path, uint64_t size, bool grow_only);
int btrfs_subvol_remove(const char *path, bool recursive);
int btrfs_subvol_remove_fd(int fd, const char *subvolume, bool recursive);

2
src/shared/machine-image.c
View File

@ -358,7 +358,7 @@ int image_remove(Image *i) {
switch (i->type) {
case IMAGE_SUBVOLUME:
return btrfs_subvol_remove(i->path);
return btrfs_subvol_remove(i->path, true);
case IMAGE_DIRECTORY:
/* Allow deletion of read-only directories */

8
src/shared/missing.h
View File

@ -428,6 +428,10 @@ struct btrfs_ioctl_clone_range_args {
#define BTRFS_FIRST_FREE_OBJECTID 256
#endif
#ifndef BTRFS_LAST_FREE_OBJECTID
#define BTRFS_LAST_FREE_OBJECTID -256ULL
#endif
#ifndef BTRFS_ROOT_TREE_OBJECTID
#define BTRFS_ROOT_TREE_OBJECTID 1
#endif
@ -452,6 +456,10 @@ struct btrfs_ioctl_clone_range_args {
#define BTRFS_QGROUP_LIMIT_KEY 244
#endif
#ifndef BTRFS_ROOT_BACKREF_KEY
#define BTRFS_ROOT_BACKREF_KEY 144
#endif
#ifndef BTRFS_SUPER_MAGIC
#define BTRFS_SUPER_MAGIC 0x9123683E
#endif

31
src/shared/rm-rf.c
View File

@ -21,6 +21,7 @@
#include "util.h"
#include "path-util.h"
#include "btrfs-util.h"
#include "rm-rf.h"
int rm_rf_children(int fd, RemoveFlags flags, struct stat *root_dev) {
@ -116,22 +117,22 @@ int rm_rf_children(int fd, RemoveFlags flags, struct stat *root_dev) {
}
if ((flags & REMOVE_SUBVOLUME) && st.st_ino == 256) {
struct btrfs_ioctl_vol_args args = {};
/* This could be a subvolume, try to remove it */
strncpy(args.name, de->d_name, sizeof(args.name)-1);
if (ioctl(fd, BTRFS_IOC_SNAP_DESTROY, &args) < 0) {
if (errno != ENOTTY && errno != EINVAL) {
r = btrfs_subvol_remove_fd(fd, de->d_name, true);
if (r < 0) {
if (r != -ENOTTY && r != -EINVAL) {
if (ret == 0)
ret = -errno;
ret = r;
safe_close(subdir_fd);
continue;
}
/* ENOTTY, then it wasn't a btrfs subvolume */
/* ENOTTY, then it wasn't a
* btrfs subvolume, continue
* below. */
} else {
/* It was a subvolume, continue. */
safe_close(subdir_fd);
@ -175,6 +176,18 @@ int rm_rf(const char *path, RemoveFlags flags) {
return -EPERM;
}
if ((flags & (REMOVE_SUBVOLUME|REMOVE_ROOT|REMOVE_PHYSICAL)) == (REMOVE_SUBVOLUME|REMOVE_ROOT|REMOVE_PHYSICAL)) {
/* Try to remove as subvolume first */
r = btrfs_subvol_remove(path, true);
if (r >= 0)
return r;
if (r != -ENOTTY && r != -EINVAL)
return r;
/* Not btrfs or not a subvolume */
}
fd = open(path, O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC|O_NOFOLLOW|O_NOATIME);
if (fd < 0) {
@ -201,8 +214,8 @@ int rm_rf(const char *path, RemoveFlags flags) {
r = rm_rf_children(fd, flags, NULL);
if (flags & REMOVE_ROOT) {
if (rmdir(path) < 0 && errno != ENOENT) {
if (r == 0)
if (rmdir(path) < 0) {
if (r == 0 && errno != ENOENT)
r = -errno;
}
}

48
src/test/test-btrfs.c
View File

@ -27,8 +27,7 @@
#include "btrfs-util.h"
int main(int argc, char *argv[]) {
int r;
int fd;
int r, fd;
fd = open("/", O_RDONLY|O_CLOEXEC|O_DIRECTORY);
if (fd < 0)
@ -81,15 +80,15 @@ int main(int argc, char *argv[]) {
if (r < 0)
log_error_errno(r, "Failed to make snapshot: %m");
r = btrfs_subvol_remove("/xxxtest");
r = btrfs_subvol_remove("/xxxtest", false);
if (r < 0)
log_error_errno(r, "Failed to remove subvolume: %m");
r = btrfs_subvol_remove("/xxxtest2");
r = btrfs_subvol_remove("/xxxtest2", false);
if (r < 0)
log_error_errno(r, "Failed to remove subvolume: %m");
r = btrfs_subvol_remove("/xxxtest3");
r = btrfs_subvol_remove("/xxxtest3", false);
if (r < 0)
log_error_errno(r, "Failed to remove subvolume: %m");
@ -97,9 +96,46 @@ int main(int argc, char *argv[]) {
if (r < 0)
log_error_errno(r, "Failed to make snapshot: %m");
r = btrfs_subvol_remove("/etc2");
r = btrfs_subvol_remove("/etc2", false);
if (r < 0)
log_error_errno(r, "Failed to remove subvolume: %m");
r = btrfs_subvol_make("/xxxrectest");
if (r < 0)
log_error_errno(r, "Failed to make subvolume: %m");
r = btrfs_subvol_make("/xxxrectest/xxxrectest2");
if (r < 0)
log_error_errno(r, "Failed to make subvolume: %m");
r = btrfs_subvol_make("/xxxrectest/xxxrectest3");
if (r < 0)
log_error_errno(r, "Failed to make subvolume: %m");
r = btrfs_subvol_make("/xxxrectest/xxxrectest3/sub");
if (r < 0)
log_error_errno(r, "Failed to make subvolume: %m");
if (mkdir("/xxxrectest/dir", 0755) < 0)
log_error_errno(errno, "Failed to make directory: %m");
r = btrfs_subvol_make("/xxxrectest/dir/xxxrectest4");
if (r < 0)
log_error_errno(r, "Failed to make subvolume: %m");
if (mkdir("/xxxrectest/dir/xxxrectest4/dir", 0755) < 0)
log_error_errno(errno, "Failed to make directory: %m");
r = btrfs_subvol_make("/xxxrectest/dir/xxxrectest4/dir/xxxrectest5");
if (r < 0)
log_error_errno(r, "Failed to make subvolume: %m");
if (mkdir("/xxxrectest/mnt", 0755) < 0)
log_error_errno(errno, "Failed to make directory: %m");
r = btrfs_subvol_remove("/xxxrectest", true);
if (r < 0)
log_error_errno(r, "Failed to recursively remove subvolume: %m");
return 0;
}

1
src/test/test-hostname.c
View File

@ -19,7 +19,6 @@
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include "hostname-setup.h"
#include "util.h"