1 /*-
2 * Copyright (c) 2019 Tomohiro Kusumi <tkusumi@netbsd.org>
3 * Copyright (c) 2019 The DragonFly Project
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 */
27
28 #include "fuse.h"
29
30 #include <sys/signalvar.h>
31 #include <sys/kern_syscall.h>
32
33 static MALLOC_DEFINE(M_FUSE_BUF, "fuse_buf", "FUSE buf");
34 static MALLOC_DEFINE(M_FUSE_IPC, "fuse_ipc", "FUSE ipc");
35
36 static struct objcache *fuse_ipc_objcache = NULL;
37 static struct objcache_malloc_args fuse_ipc_args = {
38 sizeof(struct fuse_ipc), M_FUSE_IPC,
39 };
40
41 #if 0
42 static int
43 fuse_block_sigs(sigset_t *oldset)
44 {
45 if (curproc) {
46 sigset_t newset;
47 int error;
48
49 SIGFILLSET(newset);
50 SIGDELSET(newset, SIGKILL);
51
52 error = kern_sigprocmask(SIG_BLOCK, &newset, oldset);
53 KKASSERT(!error);
54 return error;
55 }
56
57 return -1;
58 }
59
60 static int
61 fuse_restore_sigs(sigset_t *oldset)
62 {
63 if (curproc) {
64 int error = kern_sigprocmask(SIG_SETMASK, oldset, NULL);
65 KKASSERT(!error);
66 return error;
67 }
68
69 return -1;
70 }
71 #endif
72
73 void
fuse_buf_alloc(struct fuse_buf * fbp,size_t len)74 fuse_buf_alloc(struct fuse_buf *fbp, size_t len)
75 {
76 fbp->buf = kmalloc(len, M_FUSE_BUF, M_WAITOK | M_ZERO);
77 KKASSERT(fbp->buf);
78 fbp->len = len;
79 }
80
81 void
fuse_buf_free(struct fuse_buf * fbp)82 fuse_buf_free(struct fuse_buf *fbp)
83 {
84 if (fbp->buf) {
85 kfree(fbp->buf, M_FUSE_BUF);
86 fbp->buf = NULL;
87 }
88 fbp->len = 0;
89 }
90
91 struct fuse_ipc*
fuse_ipc_get(struct fuse_mount * fmp,size_t len)92 fuse_ipc_get(struct fuse_mount *fmp, size_t len)
93 {
94 struct fuse_ipc *fip;
95
96 fip = objcache_get(fuse_ipc_objcache, M_WAITOK);
97 bzero(fip, sizeof(*fip));
98 refcount_init(&fip->refcnt, 1);
99 fip->fmp = fmp;
100 fip->unique = atomic_fetchadd_long(&fmp->unique, 1);
101 fip->done = 0;
102
103 fuse_buf_alloc(&fip->request, sizeof(struct fuse_in_header) + len);
104 fip->reply.buf = NULL;
105
106 return fip;
107 }
108
109 void
fuse_ipc_put(struct fuse_ipc * fip)110 fuse_ipc_put(struct fuse_ipc *fip)
111 {
112 if (refcount_release(&fip->refcnt)) {
113 fuse_buf_free(&fip->request);
114 fuse_buf_free(&fip->reply);
115 objcache_put(fuse_ipc_objcache, fip);
116 }
117 }
118
119 static void
fuse_ipc_remove(struct fuse_ipc * fip)120 fuse_ipc_remove(struct fuse_ipc *fip)
121 {
122 struct fuse_mount *fmp = fip->fmp;
123 struct fuse_ipc *p;
124
125 mtx_lock(&fmp->ipc_lock);
126 TAILQ_FOREACH(p, &fmp->request_head, request_entry) {
127 if (fip == p) {
128 TAILQ_REMOVE(&fmp->request_head, p, request_entry);
129 if (atomic_swap_int(&fip->sent, 1) == -1)
130 wakeup(fip);
131 break;
132 }
133 }
134 TAILQ_FOREACH(p, &fmp->reply_head, reply_entry) {
135 if (fip == p) {
136 TAILQ_REMOVE(&fmp->reply_head, p, reply_entry);
137 break;
138 }
139 }
140 mtx_unlock(&fmp->ipc_lock);
141 }
142
143 void*
fuse_ipc_fill(struct fuse_ipc * fip,int op,uint64_t ino,struct ucred * cred)144 fuse_ipc_fill(struct fuse_ipc *fip, int op, uint64_t ino, struct ucred *cred)
145 {
146 if (!cred)
147 cred = curthread->td_ucred;
148
149 fuse_fill_in_header(fuse_in(fip), fuse_in_size(fip), op, fip->unique,
150 ino, cred->cr_uid, cred->cr_rgid,
151 curthread->td_proc ? curthread->td_proc->p_pid : 0);
152
153 fuse_dbgipc(fip, 0, "");
154
155 return fuse_in_data(fip);
156 }
157
158 static int
fuse_ipc_wait(struct fuse_ipc * fip)159 fuse_ipc_wait(struct fuse_ipc *fip)
160 {
161 int error, retry = 0;
162
163 if (fuse_test_dead(fip->fmp)) {
164 KKASSERT(!fuse_ipc_test_replied(fip));
165 fuse_ipc_set_replied(fip);
166 return ENOTCONN;
167 }
168
169 if (fuse_ipc_test_replied(fip))
170 return 0;
171 again:
172 tsleep_interlock(fip, 0);
173 if (fuse_ipc_test_replied(fip))
174 return 0;
175 error = tsleep(fip, PINTERLOCKED, "ftxp", 5 * hz);
176 if (!error)
177 KKASSERT(fuse_ipc_test_replied(fip));
178
179 if (error == EWOULDBLOCK) {
180 if (!fuse_ipc_test_replied(fip)) {
181 if (!retry)
182 fuse_print("timeout/retry\n");
183 if (retry++ < 6)
184 goto again;
185 fuse_print("timeout\n");
186 fuse_ipc_remove(fip);
187 fuse_ipc_set_replied(fip);
188 return ETIMEDOUT;
189 } else
190 fuse_dbg("EWOULDBLOCK lost race\n");
191 } else if (error) {
192 fuse_print("error=%d\n", error);
193 fuse_ipc_remove(fip);
194 fuse_ipc_set_replied(fip);
195 return error;
196 }
197
198 if (fuse_test_dead(fip->fmp)) {
199 KKASSERT(fuse_ipc_test_replied(fip));
200 return ENOTCONN;
201 }
202
203 return 0;
204 }
205
206 static int
fuse_ipc_wait_sent(struct fuse_ipc * fip)207 fuse_ipc_wait_sent(struct fuse_ipc *fip)
208 {
209 int error, retry = 0;
210
211 if (fuse_test_dead(fip->fmp)) {
212 KKASSERT(!fuse_ipc_test_replied(fip));
213 fuse_ipc_remove(fip);
214 fuse_ipc_set_replied(fip);
215 return ENOTCONN;
216 }
217
218 error = 0;
219
220 for (;;) {
221 tsleep_interlock(fip, 0);
222 if (atomic_swap_int(&fip->sent, -1) == 1) {
223 error = 0;
224 break;
225 }
226 error = tsleep(fip, PINTERLOCKED, "ftxp", 5 * hz);
227 if (error == EWOULDBLOCK) {
228 ++retry;
229 if (retry == 6) {
230 fuse_print("timeout\n");
231 error = ETIMEDOUT;
232 break;
233 }
234 fuse_print("timeout/retry\n");
235 }
236 }
237 if (fuse_test_dead(fip->fmp))
238 error = ENOTCONN;
239 if (error) {
240 fuse_ipc_remove(fip);
241 fuse_ipc_set_replied(fip);
242 }
243 return error;
244 }
245
246 int
fuse_ipc_tx(struct fuse_ipc * fip)247 fuse_ipc_tx(struct fuse_ipc *fip)
248 {
249 struct fuse_mount *fmp = fip->fmp;
250 struct fuse_out_header *ohd;
251 int error;
252
253 if (fuse_test_dead(fmp)) {
254 fuse_ipc_put(fip);
255 return ENOTCONN;
256 }
257
258 mtx_lock(&fmp->ipc_lock);
259 TAILQ_INSERT_TAIL(&fmp->reply_head, fip, reply_entry);
260 TAILQ_INSERT_TAIL(&fmp->request_head, fip, request_entry);
261 mtx_unlock(&fmp->ipc_lock);
262
263 wakeup(fmp);
264 KNOTE(&fmp->kq.ki_note, 0);
265
266 error = fuse_ipc_wait(fip);
267 KKASSERT(fuse_ipc_test_replied(fip));
268 if (error) {
269 fuse_dbgipc(fip, error, "ipc_wait");
270 fuse_ipc_put(fip);
271 return error;
272 }
273
274 ohd = fuse_out(fip);
275 KKASSERT(ohd);
276 error = ohd->error;
277 if (error) {
278 fuse_dbgipc(fip, error, "ipc_error");
279 fuse_ipc_put(fip);
280 if (error < 0)
281 error = -error;
282 return error;
283 }
284 fuse_dbgipc(fip, 0, "done");
285
286 return 0;
287 }
288
289 int
fuse_ipc_tx_noreply(struct fuse_ipc * fip)290 fuse_ipc_tx_noreply(struct fuse_ipc *fip)
291 {
292 struct fuse_mount *fmp = fip->fmp;
293 int error;
294
295 if (fuse_test_dead(fmp)) {
296 fuse_ipc_put(fip);
297 return ENOTCONN;
298 }
299
300 mtx_lock(&fmp->ipc_lock);
301 TAILQ_INSERT_TAIL(&fmp->request_head, fip, request_entry);
302 mtx_unlock(&fmp->ipc_lock);
303
304 wakeup(fmp);
305 KNOTE(&fmp->kq.ki_note, 0);
306
307 error = fuse_ipc_wait_sent(fip);
308 if (error)
309 fuse_ipc_put(fip);
310 return error;
311 }
312
313 void
fuse_ipc_init(void)314 fuse_ipc_init(void)
315 {
316 fuse_ipc_objcache = objcache_create("fuse_ipc", 0, 0,
317 NULL, NULL, NULL,
318 objcache_malloc_alloc_zero, objcache_malloc_free, &fuse_ipc_args);
319 }
320
321 void
fuse_ipc_cleanup(void)322 fuse_ipc_cleanup(void)
323 {
324 objcache_destroy(fuse_ipc_objcache);
325 }
326