#include <linux/ioctl.h>
#include <sys/ioctl.h>
+#include <dirent.h>
+#include <libgen.h>
#include "includes.h"
#include "system/filesys.h"
#include "smbd/smbd.h"
#include "../librpc/gen_ndr/smbXsrv.h"
#include "lib/util/tevent_ntstatus.h"
+#define SHADOW_COPY_PREFIX "@GMT-" /* vfs_shadow_copy format */
+#define SHADOW_COPY_PATH_FORMAT "@GMT-%Y.%m.%d-%H.%M.%S"
+
/*
* The following ioctl definitions are taken from the GPLv2 licensed
* btrfs_ioctl.h. Such interface definitions do not equate to copyrightable
* information; therefore, they may remain part of the GPLv3 licensed Samba
* source.
*/
+#define BTRFS_SUBVOL_RDONLY (1ULL << 1)
+#define BTRFS_SUBVOL_NAME_MAX 4039
+#define BTRFS_PATH_NAME_MAX 4087
+struct btrfs_ioctl_vol_args_v2 {
+ int64_t fd;
+ uint64_t transid;
+ uint64_t flags;
+ uint64_t unused[4];
+ char name[BTRFS_SUBVOL_NAME_MAX + 1];
+};
+struct btrfs_ioctl_vol_args {
+ int64_t fd;
+ char name[BTRFS_PATH_NAME_MAX + 1];
+};
+
struct btrfs_ioctl_clone_range_args {
int64_t src_fd;
uint64_t src_offset;
#define BTRFS_IOCTL_MAGIC 0x94
#define BTRFS_IOC_CLONE_RANGE _IOW(BTRFS_IOCTL_MAGIC, 13, \
struct btrfs_ioctl_clone_range_args)
+#define BTRFS_IOC_SNAP_DESTROY _IOW(BTRFS_IOCTL_MAGIC, 15, \
+ struct btrfs_ioctl_vol_args)
+#define BTRFS_IOC_SNAP_CREATE_V2 _IOW(BTRFS_IOCTL_MAGIC, 23, \
+ struct btrfs_ioctl_vol_args_v2)
/* end btrfs_ioctl.h based interface definitions */
struct btrfs_cc_state {
return NT_STATUS_OK;
}
+/*
+ * Check whether a path can be shadow copied. Return the base volume, allowing
+ * the caller to determine if multiple paths lie on the same base volume.
+ */
+#define BTRFS_INODE_SUBVOL 256
+static NTSTATUS btrfs_snap_check_path(struct vfs_handle_struct *handle,
+ TALLOC_CTX *mem_ctx,
+ const char *service_path,
+ char **base_volume)
+{
+ struct stat st;
+ char *base;
+
+ /* btrfs userspace uses this logic to confirm subvolume */
+ if (stat(service_path, &st) < 0) {
+ return NT_STATUS_NOT_SUPPORTED;
+ }
+ if ((st.st_ino != BTRFS_INODE_SUBVOL) || !S_ISDIR(st.st_mode)) {
+ DEBUG(0, ("%s not a btrfs subvolume, snapshots not available\n",
+ service_path));
+ return NT_STATUS_NOT_SUPPORTED;
+ }
+
+ /* we "snapshot" the service path itself */
+ base = talloc_strdup(mem_ctx, service_path);
+ if (base == NULL) {
+ return NT_STATUS_NO_MEMORY;
+ }
+ *base_volume = base;
+
+ return NT_STATUS_OK;
+}
+
+static NTSTATUS btrfs_gen_snap_dest_path(TALLOC_CTX *mem_ctx,
+ const char *src_path,
+ time_t *tstamp,
+ char **dest_path, char **subvolume)
+{
+ struct tm t_gmt;
+ char time_str[50];
+ size_t tlen;
+
+ gmtime_r(tstamp, &t_gmt);
+
+ tlen = strftime(time_str, ARRAY_SIZE(time_str),
+ SHADOW_COPY_PATH_FORMAT, &t_gmt);
+ if (tlen <= 0) {
+ return NT_STATUS_UNSUCCESSFUL;
+ }
+
+ *dest_path = talloc_strdup(mem_ctx, src_path);
+ *subvolume = talloc_strdup(mem_ctx, time_str);
+ if ((*dest_path == NULL) || (*subvolume == NULL)) {
+ return NT_STATUS_NO_MEMORY;
+ }
+
+ return NT_STATUS_OK;
+}
+
+struct btrfs_snap_create_state {
+ char *base_path;
+ char *snap_path;
+};
+
+static struct tevent_req *btrfs_snap_create_send(struct vfs_handle_struct *handle,
+ TALLOC_CTX *mem_ctx,
+ struct tevent_context *ev,
+ const char *base_volume,
+ time_t *tstamp,
+ bool rw)
+{
+ struct tevent_req *req;
+ struct btrfs_snap_create_state *create_state;
+ struct btrfs_ioctl_vol_args_v2 ioctl_arg;
+ DIR *src_dir;
+ DIR *dest_dir;
+ int src_fd;
+ int dest_fd;
+ char *dest_path;
+ char *dest_subvolume;
+ int ret;
+ NTSTATUS status;
+
+ req = tevent_req_create(mem_ctx, &create_state,
+ struct btrfs_snap_create_state);
+ if (req == NULL) {
+ return NULL;
+ }
+
+ create_state->base_path = talloc_strdup(mem_ctx, base_volume);
+ if (tevent_req_nomem(create_state->base_path, req)) {
+ return tevent_req_post(req, ev);
+ }
+
+ status = btrfs_gen_snap_dest_path(mem_ctx, base_volume, tstamp,
+ &dest_path, &dest_subvolume);
+ if (tevent_req_nterror(req, status)) {
+ return tevent_req_post(req, ev);
+ }
+
+ create_state->snap_path = talloc_asprintf(mem_ctx, "%s/%s",
+ dest_path, dest_subvolume);
+ if (tevent_req_nomem(create_state->snap_path, req)) {
+ return tevent_req_post(req, ev);
+ }
+
+ src_dir = opendir(base_volume);
+ if (src_dir == NULL) {
+ DEBUG(0, ("clone src %s open failed: %s\n",
+ base_volume, strerror(errno)));
+ tevent_req_nterror(req, map_nt_error_from_unix(errno));
+ return tevent_req_post(req, ev);
+ }
+ src_fd = dirfd(src_dir);
+ if (src_fd < 0) {
+ tevent_req_nterror(req, map_nt_error_from_unix(errno));
+ closedir(src_dir);
+ return tevent_req_post(req, ev);
+ }
+
+ dest_dir = opendir(dest_path);
+ if (dest_dir == NULL) {
+ DEBUG(0, ("clone dest %s open failed: %s\n",
+ dest_path, strerror(errno)));
+ tevent_req_nterror(req, map_nt_error_from_unix(errno));
+ closedir(src_dir);
+ return tevent_req_post(req, ev);
+ }
+ dest_fd = dirfd(dest_dir);
+ if (dest_fd < 0) {
+ tevent_req_nterror(req, map_nt_error_from_unix(errno));
+ closedir(src_dir);
+ closedir(dest_dir);
+ return tevent_req_post(req, ev);
+ }
+
+ /* avoid zeroing the entire struct here, name is 4k */
+ ioctl_arg.fd = src_fd;
+ ioctl_arg.transid = 0;
+ ioctl_arg.flags = (rw == false) ? BTRFS_SUBVOL_RDONLY : 0;
+ memset(ioctl_arg.unused, 0, ARRAY_SIZE(ioctl_arg.unused));
+ strncpy(ioctl_arg.name, dest_subvolume, ARRAY_SIZE(ioctl_arg.name));
+
+ become_root();
+ ret = ioctl(dest_fd, BTRFS_IOC_SNAP_CREATE_V2, &ioctl_arg);
+ unbecome_root();
+ if (ret < 0) {
+ DEBUG(0, ("%s -> %s(%s) BTRFS_IOC_SNAP_CREATE_V2 failed: %s\n",
+ base_volume, dest_path, dest_subvolume,
+ strerror(errno)));
+ tevent_req_nterror(req, map_nt_error_from_unix(errno));
+ closedir(src_dir);
+ closedir(dest_dir);
+ return tevent_req_post(req, ev);
+ }
+ DEBUG(5, ("%s -> %s(%s) BTRFS_IOC_SNAP_CREATE_V2 done\n",
+ base_volume, dest_path, dest_subvolume));
+
+ closedir(src_dir);
+ closedir(dest_dir);
+ tevent_req_done(req);
+ return tevent_req_post(req, ev);
+}
+
+static NTSTATUS btrfs_snap_create_recv(struct vfs_handle_struct *handle,
+ struct tevent_req *req,
+ TALLOC_CTX *mem_ctx,
+ char **base_path, char **snap_path)
+{
+ struct btrfs_snap_create_state *create_state = tevent_req_data(req,
+ struct btrfs_snap_create_state);
+ NTSTATUS status;
+
+ if (tevent_req_is_nterror(req, &status)) {
+ tevent_req_received(req);
+ return status;
+ }
+
+ *base_path = talloc_strdup(mem_ctx, create_state->base_path);
+ *snap_path = talloc_strdup(mem_ctx, create_state->snap_path);
+ tevent_req_received(req);
+ return NT_STATUS_OK;
+}
+
+static struct tevent_req *btrfs_snap_delete_send(struct vfs_handle_struct *handle,
+ TALLOC_CTX *mem_ctx,
+ struct tevent_context *ev,
+ char *snap_path)
+{
+ struct tevent_req *req;
+ char *tstr;
+ struct tm t_gmt;
+ DIR *dest_dir;
+ int dest_fd;
+ char *dest_path;
+ char *subvolume;
+ struct btrfs_ioctl_vol_args ioctl_arg;
+ int ret;
+
+ /* no state retained over delete, only the ntstatus in req */
+ req = tevent_req_create(mem_ctx, NULL, NULL);
+ if (req == NULL) {
+ return NULL;
+ }
+
+ dest_path = talloc_strdup(mem_ctx, snap_path);
+ if (tevent_req_nomem(dest_path, req)) {
+ return tevent_req_post(req, ev);
+ }
+ subvolume = talloc_strdup(mem_ctx, snap_path);
+ if (tevent_req_nomem(subvolume, req)) {
+ return tevent_req_post(req, ev);
+ }
+ dest_path = dirname(dest_path);
+ subvolume = basename(subvolume);
+
+ /* confirm snap_path matches creation format */
+ tstr = strptime(subvolume, SHADOW_COPY_PATH_FORMAT, &t_gmt);
+ if ((tstr == NULL) || (*tstr != '\0')) {
+ DEBUG(0, ("snapshot path %s does not match creation format\n",
+ snap_path));
+ tevent_req_nterror(req, NT_STATUS_UNSUCCESSFUL);
+ return tevent_req_post(req, ev);
+ }
+
+ dest_dir = opendir(dest_path);
+ if (dest_dir == NULL) {
+ DEBUG(0, ("snap destroy dest %s open failed: %s\n",
+ dest_path, strerror(errno)));
+ tevent_req_nterror(req, map_nt_error_from_unix(errno));
+ return tevent_req_post(req, ev);
+ }
+ dest_fd = dirfd(dest_dir);
+ if (dest_fd < 0) {
+ tevent_req_nterror(req, map_nt_error_from_unix(errno));
+ closedir(dest_dir);
+ return tevent_req_post(req, ev);
+ }
+
+ ioctl_arg.fd = -1; /* not needed */
+ strncpy(ioctl_arg.name, subvolume, ARRAY_SIZE(ioctl_arg.name));
+
+ become_root();
+ ret = ioctl(dest_fd, BTRFS_IOC_SNAP_DESTROY, &ioctl_arg);
+ unbecome_root();
+ if (ret < 0) {
+ DEBUG(0, ("%s(%s) BTRFS_IOC_SNAP_DESTROY failed: %s\n",
+ dest_path, subvolume, strerror(errno)));
+ tevent_req_nterror(req, map_nt_error_from_unix(errno));
+ closedir(dest_dir);
+ return tevent_req_post(req, ev);
+ }
+ DEBUG(5, ("%s(%s) BTRFS_IOC_SNAP_DESTROY done\n",
+ dest_path, subvolume));
+
+ closedir(dest_dir);
+ tevent_req_done(req);
+ return tevent_req_post(req, ev);
+}
+
+static NTSTATUS btrfs_snap_delete_recv(struct vfs_handle_struct *handle,
+ struct tevent_req *req)
+{
+ NTSTATUS status;
+
+ if (tevent_req_is_nterror(req, &status)) {
+ tevent_req_received(req);
+ return status;
+ }
+ tevent_req_received(req);
+ return NT_STATUS_OK;
+}
+
static struct vfs_fn_pointers btrfs_fns = {
.copy_chunk_send_fn = btrfs_copy_chunk_send,
.copy_chunk_recv_fn = btrfs_copy_chunk_recv,
+ .snap_check_path_fn = btrfs_snap_check_path,
+ .snap_create_send_fn = btrfs_snap_create_send,
+ .snap_create_recv_fn = btrfs_snap_create_recv,
+ .snap_delete_send_fn = btrfs_snap_delete_send,
+ .snap_delete_recv_fn = btrfs_snap_delete_recv,
};
NTSTATUS vfs_btrfs_init(void);
git.samba.org / ddiss / samba.git / commitdiff