2 * Module to make use of awesome Btrfs features
4 * Copyright (C) David Disseldorp 2011-2013
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 3 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, see <http://www.gnu.org/licenses/>.
20 #include <linux/ioctl.h>
21 #include <sys/ioctl.h>
23 #include "system/filesys.h"
24 #include "smbd/smbd.h"
25 #include "../librpc/gen_ndr/smbXsrv.h"
26 #include "lib/util/tevent_ntstatus.h"
28 struct btrfs_ioctl_clone_range_args {
35 #define BTRFS_IOCTL_MAGIC 0x94
36 #define BTRFS_IOC_CLONE_RANGE _IOW(BTRFS_IOCTL_MAGIC, 13, \
37 struct btrfs_ioctl_clone_range_args)
39 struct btrfs_cc_state {
40 struct vfs_handle_struct *handle;
42 struct tevent_req *subreq; /* non-null if passed to next VFS fn */
44 static void btrfs_copy_chunk_done(struct tevent_req *subreq);
46 static struct tevent_req *btrfs_copy_chunk_send(struct vfs_handle_struct *handle,
48 struct tevent_context *ev,
49 struct files_struct *src_fsp,
51 struct files_struct *dest_fsp,
55 struct tevent_req *req;
56 struct btrfs_cc_state *cc_state;
57 struct btrfs_ioctl_clone_range_args cr_args;
58 struct lock_struct src_lck;
59 struct lock_struct dest_lck;
63 req = tevent_req_create(mem_ctx, &cc_state, struct btrfs_cc_state);
67 cc_state->handle = handle;
69 status = vfs_stat_fsp(src_fsp);
70 if (tevent_req_nterror(req, status)) {
71 return tevent_req_post(req, ev);
74 if (src_fsp->fsp_name->st.st_ex_size < src_off + num) {
75 /* [MS-SMB2] Handling a Server-Side Data Copy Request */
76 tevent_req_nterror(req, NT_STATUS_INVALID_VIEW_SIZE);
77 return tevent_req_post(req, ev);
80 init_strict_lock_struct(src_fsp,
81 src_fsp->op->global->open_persistent_id,
86 init_strict_lock_struct(dest_fsp,
87 dest_fsp->op->global->open_persistent_id,
93 if (!SMB_VFS_STRICT_LOCK(src_fsp->conn, src_fsp, &src_lck)) {
94 tevent_req_nterror(req, NT_STATUS_FILE_LOCK_CONFLICT);
95 return tevent_req_post(req, ev);
97 if (!SMB_VFS_STRICT_LOCK(dest_fsp->conn, dest_fsp, &dest_lck)) {
98 SMB_VFS_STRICT_UNLOCK(src_fsp->conn, src_fsp, &src_lck);
99 tevent_req_nterror(req, NT_STATUS_FILE_LOCK_CONFLICT);
100 return tevent_req_post(req, ev);
103 ZERO_STRUCT(cr_args);
104 cr_args.src_fd = src_fsp->fh->fd;
105 cr_args.src_offset = (uint64_t)src_off;
106 cr_args.dest_offset = (uint64_t)dest_off;
107 cr_args.src_length = (uint64_t)num;
109 ret = ioctl(dest_fsp->fh->fd, BTRFS_IOC_CLONE_RANGE, &cr_args);
110 SMB_VFS_STRICT_UNLOCK(src_fsp->conn, src_fsp, &dest_lck);
111 SMB_VFS_STRICT_UNLOCK(src_fsp->conn, src_fsp, &src_lck);
114 * BTRFS_IOC_CLONE_RANGE only supports 'sectorsize' aligned
115 * cloning. Which is 4096 by default, therefore fall back to
116 * manual read/write on failure.
118 DEBUG(5, ("BTRFS_IOC_CLONE_RANGE failed: %s, length %llu, "
119 "src fd: %lld off: %llu, dest fd: %d off: %llu\n",
121 (unsigned long long)cr_args.src_length,
122 (long long)cr_args.src_fd,
123 (unsigned long long)cr_args.src_offset,
125 (unsigned long long)cr_args.dest_offset));
126 cc_state->subreq = SMB_VFS_NEXT_COPY_CHUNK_SEND(handle,
132 if (tevent_req_nomem(cc_state->subreq, req)) {
133 return tevent_req_post(req, ev);
135 /* wait for subreq completion */
136 tevent_req_set_callback(cc_state->subreq,
137 btrfs_copy_chunk_done,
143 DEBUG(5, ("BTRFS_IOC_CLONE_RANGE returned %d\n", ret));
144 /* BTRFS_IOC_CLONE_RANGE is all or nothing */
145 cc_state->copied = num;
146 tevent_req_done(req);
147 return tevent_req_post(req, ev);
150 /* only used if the request is passed through to next VFS module */
151 static void btrfs_copy_chunk_done(struct tevent_req *subreq)
153 struct tevent_req *req = tevent_req_callback_data(
154 subreq, struct tevent_req);
155 struct btrfs_cc_state *cc_state = tevent_req_data(req,
156 struct btrfs_cc_state);
159 status = SMB_VFS_NEXT_COPY_CHUNK_RECV(cc_state->handle,
162 if (tevent_req_nterror(req, status)) {
165 tevent_req_done(req);
168 static NTSTATUS btrfs_copy_chunk_recv(struct vfs_handle_struct *handle,
169 struct tevent_req *req,
173 struct btrfs_cc_state *cc_state = tevent_req_data(req,
174 struct btrfs_cc_state);
176 if (tevent_req_is_nterror(req, &status)) {
177 DEBUG(4, ("server side copy chunk failed: %s\n",
179 tevent_req_received(req);
183 DEBUG(10, ("server side copy chunk copied %llu\n",
184 (unsigned long long)cc_state->copied));
185 *copied = cc_state->copied;
186 tevent_req_received(req);
190 static struct vfs_fn_pointers btrfs_fns = {
191 .copy_chunk_send_fn = btrfs_copy_chunk_send,
192 .copy_chunk_recv_fn = btrfs_copy_chunk_recv,
195 NTSTATUS vfs_btrfs_init(void);
196 NTSTATUS vfs_btrfs_init(void)
198 return smb_register_vfs(SMB_VFS_INTERFACE_VERSION,
199 "btrfs", &btrfs_fns);