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Commit | Line | Data |
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334f485d MS |
1 | /* |
2 | FUSE: Filesystem in Userspace | |
1729a16c | 3 | Copyright (C) 2001-2008 Miklos Szeredi <miklos@szeredi.hu> |
334f485d MS |
4 | |
5 | This program can be distributed under the terms of the GNU GPL. | |
6 | See the file COPYING. | |
7 | */ | |
8 | ||
9 | #include "fuse_i.h" | |
10 | ||
11 | #include <linux/init.h> | |
12 | #include <linux/module.h> | |
13 | #include <linux/poll.h> | |
174cd4b1 | 14 | #include <linux/sched/signal.h> |
334f485d MS |
15 | #include <linux/uio.h> |
16 | #include <linux/miscdevice.h> | |
17 | #include <linux/pagemap.h> | |
18 | #include <linux/file.h> | |
19 | #include <linux/slab.h> | |
dd3bb14f | 20 | #include <linux/pipe_fs_i.h> |
ce534fb0 MS |
21 | #include <linux/swap.h> |
22 | #include <linux/splice.h> | |
0b6e9ea0 | 23 | #include <linux/sched.h> |
334f485d MS |
24 | |
25 | MODULE_ALIAS_MISCDEV(FUSE_MINOR); | |
578454ff | 26 | MODULE_ALIAS("devname:fuse"); |
334f485d | 27 | |
e18b890b | 28 | static struct kmem_cache *fuse_req_cachep; |
334f485d | 29 | |
cc080e9e | 30 | static struct fuse_dev *fuse_get_dev(struct file *file) |
334f485d | 31 | { |
0720b315 MS |
32 | /* |
33 | * Lockless access is OK, because file->private data is set | |
34 | * once during mount and is valid until the file is released. | |
35 | */ | |
cc080e9e | 36 | return ACCESS_ONCE(file->private_data); |
334f485d MS |
37 | } |
38 | ||
4250c066 | 39 | static void fuse_request_init(struct fuse_req *req, struct page **pages, |
b2430d75 | 40 | struct fuse_page_desc *page_descs, |
4250c066 | 41 | unsigned npages) |
334f485d MS |
42 | { |
43 | memset(req, 0, sizeof(*req)); | |
4250c066 | 44 | memset(pages, 0, sizeof(*pages) * npages); |
b2430d75 | 45 | memset(page_descs, 0, sizeof(*page_descs) * npages); |
334f485d | 46 | INIT_LIST_HEAD(&req->list); |
a4d27e75 | 47 | INIT_LIST_HEAD(&req->intr_entry); |
334f485d | 48 | init_waitqueue_head(&req->waitq); |
ec99f6d3 | 49 | refcount_set(&req->count, 1); |
4250c066 | 50 | req->pages = pages; |
b2430d75 | 51 | req->page_descs = page_descs; |
4250c066 | 52 | req->max_pages = npages; |
33e14b4d | 53 | __set_bit(FR_PENDING, &req->flags); |
334f485d MS |
54 | } |
55 | ||
4250c066 | 56 | static struct fuse_req *__fuse_request_alloc(unsigned npages, gfp_t flags) |
334f485d | 57 | { |
4250c066 MP |
58 | struct fuse_req *req = kmem_cache_alloc(fuse_req_cachep, flags); |
59 | if (req) { | |
60 | struct page **pages; | |
b2430d75 | 61 | struct fuse_page_desc *page_descs; |
4250c066 | 62 | |
b2430d75 | 63 | if (npages <= FUSE_REQ_INLINE_PAGES) { |
4250c066 | 64 | pages = req->inline_pages; |
b2430d75 MP |
65 | page_descs = req->inline_page_descs; |
66 | } else { | |
4250c066 | 67 | pages = kmalloc(sizeof(struct page *) * npages, flags); |
b2430d75 MP |
68 | page_descs = kmalloc(sizeof(struct fuse_page_desc) * |
69 | npages, flags); | |
70 | } | |
4250c066 | 71 | |
b2430d75 MP |
72 | if (!pages || !page_descs) { |
73 | kfree(pages); | |
74 | kfree(page_descs); | |
4250c066 MP |
75 | kmem_cache_free(fuse_req_cachep, req); |
76 | return NULL; | |
77 | } | |
78 | ||
b2430d75 | 79 | fuse_request_init(req, pages, page_descs, npages); |
4250c066 | 80 | } |
334f485d MS |
81 | return req; |
82 | } | |
4250c066 MP |
83 | |
84 | struct fuse_req *fuse_request_alloc(unsigned npages) | |
85 | { | |
86 | return __fuse_request_alloc(npages, GFP_KERNEL); | |
87 | } | |
08cbf542 | 88 | EXPORT_SYMBOL_GPL(fuse_request_alloc); |
334f485d | 89 | |
4250c066 | 90 | struct fuse_req *fuse_request_alloc_nofs(unsigned npages) |
3be5a52b | 91 | { |
4250c066 | 92 | return __fuse_request_alloc(npages, GFP_NOFS); |
3be5a52b MS |
93 | } |
94 | ||
334f485d MS |
95 | void fuse_request_free(struct fuse_req *req) |
96 | { | |
b2430d75 | 97 | if (req->pages != req->inline_pages) { |
4250c066 | 98 | kfree(req->pages); |
b2430d75 MP |
99 | kfree(req->page_descs); |
100 | } | |
334f485d MS |
101 | kmem_cache_free(fuse_req_cachep, req); |
102 | } | |
103 | ||
36cf66ed | 104 | void __fuse_get_request(struct fuse_req *req) |
334f485d | 105 | { |
ec99f6d3 | 106 | refcount_inc(&req->count); |
334f485d MS |
107 | } |
108 | ||
109 | /* Must be called with > 1 refcount */ | |
110 | static void __fuse_put_request(struct fuse_req *req) | |
111 | { | |
ec99f6d3 | 112 | refcount_dec(&req->count); |
334f485d MS |
113 | } |
114 | ||
0b6e9ea0 | 115 | static void fuse_req_init_context(struct fuse_conn *fc, struct fuse_req *req) |
33649c91 | 116 | { |
499dcf20 EB |
117 | req->in.h.uid = from_kuid_munged(&init_user_ns, current_fsuid()); |
118 | req->in.h.gid = from_kgid_munged(&init_user_ns, current_fsgid()); | |
0b6e9ea0 | 119 | req->in.h.pid = pid_nr_ns(task_pid(current), fc->pid_ns); |
33649c91 MS |
120 | } |
121 | ||
9759bd51 MS |
122 | void fuse_set_initialized(struct fuse_conn *fc) |
123 | { | |
124 | /* Make sure stores before this are seen on another CPU */ | |
125 | smp_wmb(); | |
126 | fc->initialized = 1; | |
127 | } | |
128 | ||
0aada884 MP |
129 | static bool fuse_block_alloc(struct fuse_conn *fc, bool for_background) |
130 | { | |
131 | return !fc->initialized || (for_background && fc->blocked); | |
132 | } | |
133 | ||
8b41e671 MP |
134 | static struct fuse_req *__fuse_get_req(struct fuse_conn *fc, unsigned npages, |
135 | bool for_background) | |
334f485d | 136 | { |
08a53cdc | 137 | struct fuse_req *req; |
08a53cdc | 138 | int err; |
9bc5ddda | 139 | atomic_inc(&fc->num_waiting); |
0aada884 MP |
140 | |
141 | if (fuse_block_alloc(fc, for_background)) { | |
0aada884 | 142 | err = -EINTR; |
7d3a07fc AV |
143 | if (wait_event_killable_exclusive(fc->blocked_waitq, |
144 | !fuse_block_alloc(fc, for_background))) | |
0aada884 MP |
145 | goto out; |
146 | } | |
9759bd51 MS |
147 | /* Matches smp_wmb() in fuse_set_initialized() */ |
148 | smp_rmb(); | |
08a53cdc | 149 | |
51eb01e7 MS |
150 | err = -ENOTCONN; |
151 | if (!fc->connected) | |
152 | goto out; | |
153 | ||
de155226 MS |
154 | err = -ECONNREFUSED; |
155 | if (fc->conn_error) | |
156 | goto out; | |
157 | ||
b111c8c0 | 158 | req = fuse_request_alloc(npages); |
9bc5ddda | 159 | err = -ENOMEM; |
722d2bea MP |
160 | if (!req) { |
161 | if (for_background) | |
162 | wake_up(&fc->blocked_waitq); | |
9bc5ddda | 163 | goto out; |
722d2bea | 164 | } |
334f485d | 165 | |
0b6e9ea0 | 166 | fuse_req_init_context(fc, req); |
825d6d33 MS |
167 | __set_bit(FR_WAITING, &req->flags); |
168 | if (for_background) | |
169 | __set_bit(FR_BACKGROUND, &req->flags); | |
170 | ||
334f485d | 171 | return req; |
9bc5ddda MS |
172 | |
173 | out: | |
174 | atomic_dec(&fc->num_waiting); | |
175 | return ERR_PTR(err); | |
334f485d | 176 | } |
8b41e671 MP |
177 | |
178 | struct fuse_req *fuse_get_req(struct fuse_conn *fc, unsigned npages) | |
179 | { | |
180 | return __fuse_get_req(fc, npages, false); | |
181 | } | |
08cbf542 | 182 | EXPORT_SYMBOL_GPL(fuse_get_req); |
334f485d | 183 | |
8b41e671 MP |
184 | struct fuse_req *fuse_get_req_for_background(struct fuse_conn *fc, |
185 | unsigned npages) | |
186 | { | |
187 | return __fuse_get_req(fc, npages, true); | |
188 | } | |
189 | EXPORT_SYMBOL_GPL(fuse_get_req_for_background); | |
190 | ||
33649c91 MS |
191 | /* |
192 | * Return request in fuse_file->reserved_req. However that may | |
193 | * currently be in use. If that is the case, wait for it to become | |
194 | * available. | |
195 | */ | |
196 | static struct fuse_req *get_reserved_req(struct fuse_conn *fc, | |
197 | struct file *file) | |
198 | { | |
199 | struct fuse_req *req = NULL; | |
200 | struct fuse_file *ff = file->private_data; | |
201 | ||
202 | do { | |
de5e3dec | 203 | wait_event(fc->reserved_req_waitq, ff->reserved_req); |
33649c91 MS |
204 | spin_lock(&fc->lock); |
205 | if (ff->reserved_req) { | |
206 | req = ff->reserved_req; | |
207 | ff->reserved_req = NULL; | |
cb0942b8 | 208 | req->stolen_file = get_file(file); |
33649c91 MS |
209 | } |
210 | spin_unlock(&fc->lock); | |
211 | } while (!req); | |
212 | ||
213 | return req; | |
214 | } | |
215 | ||
216 | /* | |
217 | * Put stolen request back into fuse_file->reserved_req | |
218 | */ | |
219 | static void put_reserved_req(struct fuse_conn *fc, struct fuse_req *req) | |
220 | { | |
221 | struct file *file = req->stolen_file; | |
222 | struct fuse_file *ff = file->private_data; | |
223 | ||
224 | spin_lock(&fc->lock); | |
b2430d75 | 225 | fuse_request_init(req, req->pages, req->page_descs, req->max_pages); |
33649c91 MS |
226 | BUG_ON(ff->reserved_req); |
227 | ff->reserved_req = req; | |
de5e3dec | 228 | wake_up_all(&fc->reserved_req_waitq); |
33649c91 MS |
229 | spin_unlock(&fc->lock); |
230 | fput(file); | |
231 | } | |
232 | ||
233 | /* | |
234 | * Gets a requests for a file operation, always succeeds | |
235 | * | |
236 | * This is used for sending the FLUSH request, which must get to | |
237 | * userspace, due to POSIX locks which may need to be unlocked. | |
238 | * | |
239 | * If allocation fails due to OOM, use the reserved request in | |
240 | * fuse_file. | |
241 | * | |
242 | * This is very unlikely to deadlock accidentally, since the | |
243 | * filesystem should not have it's own file open. If deadlock is | |
244 | * intentional, it can still be broken by "aborting" the filesystem. | |
245 | */ | |
b111c8c0 MP |
246 | struct fuse_req *fuse_get_req_nofail_nopages(struct fuse_conn *fc, |
247 | struct file *file) | |
33649c91 MS |
248 | { |
249 | struct fuse_req *req; | |
250 | ||
251 | atomic_inc(&fc->num_waiting); | |
0aada884 | 252 | wait_event(fc->blocked_waitq, fc->initialized); |
9759bd51 MS |
253 | /* Matches smp_wmb() in fuse_set_initialized() */ |
254 | smp_rmb(); | |
b111c8c0 | 255 | req = fuse_request_alloc(0); |
33649c91 MS |
256 | if (!req) |
257 | req = get_reserved_req(fc, file); | |
258 | ||
0b6e9ea0 | 259 | fuse_req_init_context(fc, req); |
825d6d33 MS |
260 | __set_bit(FR_WAITING, &req->flags); |
261 | __clear_bit(FR_BACKGROUND, &req->flags); | |
33649c91 MS |
262 | return req; |
263 | } | |
264 | ||
334f485d | 265 | void fuse_put_request(struct fuse_conn *fc, struct fuse_req *req) |
7128ec2a | 266 | { |
ec99f6d3 | 267 | if (refcount_dec_and_test(&req->count)) { |
825d6d33 | 268 | if (test_bit(FR_BACKGROUND, &req->flags)) { |
722d2bea MP |
269 | /* |
270 | * We get here in the unlikely case that a background | |
271 | * request was allocated but not sent | |
272 | */ | |
273 | spin_lock(&fc->lock); | |
274 | if (!fc->blocked) | |
275 | wake_up(&fc->blocked_waitq); | |
276 | spin_unlock(&fc->lock); | |
277 | } | |
278 | ||
825d6d33 MS |
279 | if (test_bit(FR_WAITING, &req->flags)) { |
280 | __clear_bit(FR_WAITING, &req->flags); | |
9bc5ddda | 281 | atomic_dec(&fc->num_waiting); |
73e0e738 | 282 | } |
33649c91 MS |
283 | |
284 | if (req->stolen_file) | |
285 | put_reserved_req(fc, req); | |
286 | else | |
287 | fuse_request_free(req); | |
7128ec2a MS |
288 | } |
289 | } | |
08cbf542 | 290 | EXPORT_SYMBOL_GPL(fuse_put_request); |
7128ec2a | 291 | |
d12def1b MS |
292 | static unsigned len_args(unsigned numargs, struct fuse_arg *args) |
293 | { | |
294 | unsigned nbytes = 0; | |
295 | unsigned i; | |
296 | ||
297 | for (i = 0; i < numargs; i++) | |
298 | nbytes += args[i].size; | |
299 | ||
300 | return nbytes; | |
301 | } | |
302 | ||
f88996a9 | 303 | static u64 fuse_get_unique(struct fuse_iqueue *fiq) |
d12def1b | 304 | { |
f88996a9 | 305 | return ++fiq->reqctr; |
d12def1b MS |
306 | } |
307 | ||
f88996a9 | 308 | static void queue_request(struct fuse_iqueue *fiq, struct fuse_req *req) |
d12def1b | 309 | { |
d12def1b MS |
310 | req->in.h.len = sizeof(struct fuse_in_header) + |
311 | len_args(req->in.numargs, (struct fuse_arg *) req->in.args); | |
f88996a9 | 312 | list_add_tail(&req->list, &fiq->pending); |
4ce60812 | 313 | wake_up_locked(&fiq->waitq); |
f88996a9 | 314 | kill_fasync(&fiq->fasync, SIGIO, POLL_IN); |
d12def1b MS |
315 | } |
316 | ||
07e77dca MS |
317 | void fuse_queue_forget(struct fuse_conn *fc, struct fuse_forget_link *forget, |
318 | u64 nodeid, u64 nlookup) | |
319 | { | |
f88996a9 MS |
320 | struct fuse_iqueue *fiq = &fc->iq; |
321 | ||
02c048b9 MS |
322 | forget->forget_one.nodeid = nodeid; |
323 | forget->forget_one.nlookup = nlookup; | |
07e77dca | 324 | |
4ce60812 | 325 | spin_lock(&fiq->waitq.lock); |
e16714d8 | 326 | if (fiq->connected) { |
f88996a9 MS |
327 | fiq->forget_list_tail->next = forget; |
328 | fiq->forget_list_tail = forget; | |
4ce60812 | 329 | wake_up_locked(&fiq->waitq); |
f88996a9 | 330 | kill_fasync(&fiq->fasync, SIGIO, POLL_IN); |
5dfcc87f MS |
331 | } else { |
332 | kfree(forget); | |
333 | } | |
4ce60812 | 334 | spin_unlock(&fiq->waitq.lock); |
07e77dca MS |
335 | } |
336 | ||
d12def1b MS |
337 | static void flush_bg_queue(struct fuse_conn *fc) |
338 | { | |
7a6d3c8b | 339 | while (fc->active_background < fc->max_background && |
d12def1b MS |
340 | !list_empty(&fc->bg_queue)) { |
341 | struct fuse_req *req; | |
f88996a9 | 342 | struct fuse_iqueue *fiq = &fc->iq; |
d12def1b MS |
343 | |
344 | req = list_entry(fc->bg_queue.next, struct fuse_req, list); | |
345 | list_del(&req->list); | |
346 | fc->active_background++; | |
4ce60812 | 347 | spin_lock(&fiq->waitq.lock); |
f88996a9 MS |
348 | req->in.h.unique = fuse_get_unique(fiq); |
349 | queue_request(fiq, req); | |
4ce60812 | 350 | spin_unlock(&fiq->waitq.lock); |
d12def1b MS |
351 | } |
352 | } | |
353 | ||
334f485d MS |
354 | /* |
355 | * This function is called when a request is finished. Either a reply | |
f9a2842e | 356 | * has arrived or it was aborted (and not yet sent) or some error |
f43b155a | 357 | * occurred during communication with userspace, or the device file |
51eb01e7 MS |
358 | * was closed. The requester thread is woken up (if still waiting), |
359 | * the 'end' callback is called if given, else the reference to the | |
360 | * request is released | |
334f485d MS |
361 | */ |
362 | static void request_end(struct fuse_conn *fc, struct fuse_req *req) | |
363 | { | |
4ce60812 | 364 | struct fuse_iqueue *fiq = &fc->iq; |
365ae710 | 365 | |
efe2800f | 366 | if (test_and_set_bit(FR_FINISHED, &req->flags)) |
365ae710 | 367 | return; |
365ae710 | 368 | |
4ce60812 | 369 | spin_lock(&fiq->waitq.lock); |
0d8e84b0 | 370 | list_del_init(&req->intr_entry); |
4ce60812 | 371 | spin_unlock(&fiq->waitq.lock); |
33e14b4d MS |
372 | WARN_ON(test_bit(FR_PENDING, &req->flags)); |
373 | WARN_ON(test_bit(FR_SENT, &req->flags)); | |
825d6d33 | 374 | if (test_bit(FR_BACKGROUND, &req->flags)) { |
efe2800f | 375 | spin_lock(&fc->lock); |
825d6d33 | 376 | clear_bit(FR_BACKGROUND, &req->flags); |
722d2bea | 377 | if (fc->num_background == fc->max_background) |
51eb01e7 | 378 | fc->blocked = 0; |
722d2bea MP |
379 | |
380 | /* Wake up next waiter, if any */ | |
3c18ef81 | 381 | if (!fc->blocked && waitqueue_active(&fc->blocked_waitq)) |
722d2bea MP |
382 | wake_up(&fc->blocked_waitq); |
383 | ||
7a6d3c8b | 384 | if (fc->num_background == fc->congestion_threshold && |
7fbbe972 | 385 | fc->connected && fc->sb) { |
5f7f7543 JK |
386 | clear_bdi_congested(fc->sb->s_bdi, BLK_RW_SYNC); |
387 | clear_bdi_congested(fc->sb->s_bdi, BLK_RW_ASYNC); | |
f92b99b9 | 388 | } |
51eb01e7 | 389 | fc->num_background--; |
d12def1b MS |
390 | fc->active_background--; |
391 | flush_bg_queue(fc); | |
efe2800f | 392 | spin_unlock(&fc->lock); |
334f485d | 393 | } |
51eb01e7 | 394 | wake_up(&req->waitq); |
1e6881c3 MS |
395 | if (req->end) |
396 | req->end(fc, req); | |
e9bb09dd | 397 | fuse_put_request(fc, req); |
334f485d MS |
398 | } |
399 | ||
f88996a9 | 400 | static void queue_interrupt(struct fuse_iqueue *fiq, struct fuse_req *req) |
a4d27e75 | 401 | { |
4ce60812 | 402 | spin_lock(&fiq->waitq.lock); |
6ba4d272 ST |
403 | if (test_bit(FR_FINISHED, &req->flags)) { |
404 | spin_unlock(&fiq->waitq.lock); | |
405 | return; | |
406 | } | |
8f7bb368 MS |
407 | if (list_empty(&req->intr_entry)) { |
408 | list_add_tail(&req->intr_entry, &fiq->interrupts); | |
409 | wake_up_locked(&fiq->waitq); | |
410 | } | |
4ce60812 | 411 | spin_unlock(&fiq->waitq.lock); |
f88996a9 | 412 | kill_fasync(&fiq->fasync, SIGIO, POLL_IN); |
a4d27e75 MS |
413 | } |
414 | ||
7c352bdf | 415 | static void request_wait_answer(struct fuse_conn *fc, struct fuse_req *req) |
334f485d | 416 | { |
4ce60812 | 417 | struct fuse_iqueue *fiq = &fc->iq; |
c4775267 MS |
418 | int err; |
419 | ||
a4d27e75 MS |
420 | if (!fc->no_interrupt) { |
421 | /* Any signal may interrupt this */ | |
c4775267 | 422 | err = wait_event_interruptible(req->waitq, |
33e14b4d | 423 | test_bit(FR_FINISHED, &req->flags)); |
c4775267 | 424 | if (!err) |
a4d27e75 MS |
425 | return; |
426 | ||
825d6d33 | 427 | set_bit(FR_INTERRUPTED, &req->flags); |
8f7bb368 MS |
428 | /* matches barrier in fuse_dev_do_read() */ |
429 | smp_mb__after_atomic(); | |
33e14b4d | 430 | if (test_bit(FR_SENT, &req->flags)) |
4ce60812 | 431 | queue_interrupt(fiq, req); |
a4d27e75 MS |
432 | } |
433 | ||
825d6d33 | 434 | if (!test_bit(FR_FORCE, &req->flags)) { |
a4d27e75 | 435 | /* Only fatal signals may interrupt this */ |
7d3a07fc | 436 | err = wait_event_killable(req->waitq, |
33e14b4d | 437 | test_bit(FR_FINISHED, &req->flags)); |
c4775267 | 438 | if (!err) |
a131de0a MS |
439 | return; |
440 | ||
4ce60812 | 441 | spin_lock(&fiq->waitq.lock); |
a131de0a | 442 | /* Request is not yet in userspace, bail out */ |
33e14b4d | 443 | if (test_bit(FR_PENDING, &req->flags)) { |
a131de0a | 444 | list_del(&req->list); |
4ce60812 | 445 | spin_unlock(&fiq->waitq.lock); |
a131de0a MS |
446 | __fuse_put_request(req); |
447 | req->out.h.error = -EINTR; | |
448 | return; | |
449 | } | |
4ce60812 | 450 | spin_unlock(&fiq->waitq.lock); |
51eb01e7 | 451 | } |
334f485d | 452 | |
a131de0a MS |
453 | /* |
454 | * Either request is already in userspace, or it was forced. | |
455 | * Wait it out. | |
456 | */ | |
33e14b4d | 457 | wait_event(req->waitq, test_bit(FR_FINISHED, &req->flags)); |
334f485d MS |
458 | } |
459 | ||
6a4e922c | 460 | static void __fuse_request_send(struct fuse_conn *fc, struct fuse_req *req) |
334f485d | 461 | { |
e16714d8 MS |
462 | struct fuse_iqueue *fiq = &fc->iq; |
463 | ||
825d6d33 | 464 | BUG_ON(test_bit(FR_BACKGROUND, &req->flags)); |
4ce60812 | 465 | spin_lock(&fiq->waitq.lock); |
e16714d8 | 466 | if (!fiq->connected) { |
4ce60812 | 467 | spin_unlock(&fiq->waitq.lock); |
334f485d | 468 | req->out.h.error = -ENOTCONN; |
c4775267 | 469 | } else { |
f88996a9 MS |
470 | req->in.h.unique = fuse_get_unique(fiq); |
471 | queue_request(fiq, req); | |
334f485d MS |
472 | /* acquire extra reference, since request is still needed |
473 | after request_end() */ | |
474 | __fuse_get_request(req); | |
4ce60812 | 475 | spin_unlock(&fiq->waitq.lock); |
334f485d | 476 | |
7c352bdf | 477 | request_wait_answer(fc, req); |
c4775267 MS |
478 | /* Pairs with smp_wmb() in request_end() */ |
479 | smp_rmb(); | |
334f485d | 480 | } |
334f485d | 481 | } |
6a4e922c EW |
482 | |
483 | void fuse_request_send(struct fuse_conn *fc, struct fuse_req *req) | |
484 | { | |
825d6d33 MS |
485 | __set_bit(FR_ISREPLY, &req->flags); |
486 | if (!test_bit(FR_WAITING, &req->flags)) { | |
487 | __set_bit(FR_WAITING, &req->flags); | |
5437f241 MS |
488 | atomic_inc(&fc->num_waiting); |
489 | } | |
6a4e922c EW |
490 | __fuse_request_send(fc, req); |
491 | } | |
08cbf542 | 492 | EXPORT_SYMBOL_GPL(fuse_request_send); |
334f485d | 493 | |
21f62174 MS |
494 | static void fuse_adjust_compat(struct fuse_conn *fc, struct fuse_args *args) |
495 | { | |
496 | if (fc->minor < 4 && args->in.h.opcode == FUSE_STATFS) | |
497 | args->out.args[0].size = FUSE_COMPAT_STATFS_SIZE; | |
498 | ||
499 | if (fc->minor < 9) { | |
500 | switch (args->in.h.opcode) { | |
501 | case FUSE_LOOKUP: | |
502 | case FUSE_CREATE: | |
503 | case FUSE_MKNOD: | |
504 | case FUSE_MKDIR: | |
505 | case FUSE_SYMLINK: | |
506 | case FUSE_LINK: | |
507 | args->out.args[0].size = FUSE_COMPAT_ENTRY_OUT_SIZE; | |
508 | break; | |
509 | case FUSE_GETATTR: | |
510 | case FUSE_SETATTR: | |
511 | args->out.args[0].size = FUSE_COMPAT_ATTR_OUT_SIZE; | |
512 | break; | |
513 | } | |
514 | } | |
515 | if (fc->minor < 12) { | |
516 | switch (args->in.h.opcode) { | |
517 | case FUSE_CREATE: | |
518 | args->in.args[0].size = sizeof(struct fuse_open_in); | |
519 | break; | |
520 | case FUSE_MKNOD: | |
521 | args->in.args[0].size = FUSE_COMPAT_MKNOD_IN_SIZE; | |
522 | break; | |
523 | } | |
524 | } | |
525 | } | |
526 | ||
7078187a MS |
527 | ssize_t fuse_simple_request(struct fuse_conn *fc, struct fuse_args *args) |
528 | { | |
529 | struct fuse_req *req; | |
530 | ssize_t ret; | |
531 | ||
532 | req = fuse_get_req(fc, 0); | |
533 | if (IS_ERR(req)) | |
534 | return PTR_ERR(req); | |
535 | ||
21f62174 MS |
536 | /* Needs to be done after fuse_get_req() so that fc->minor is valid */ |
537 | fuse_adjust_compat(fc, args); | |
538 | ||
7078187a MS |
539 | req->in.h.opcode = args->in.h.opcode; |
540 | req->in.h.nodeid = args->in.h.nodeid; | |
541 | req->in.numargs = args->in.numargs; | |
542 | memcpy(req->in.args, args->in.args, | |
543 | args->in.numargs * sizeof(struct fuse_in_arg)); | |
544 | req->out.argvar = args->out.argvar; | |
545 | req->out.numargs = args->out.numargs; | |
546 | memcpy(req->out.args, args->out.args, | |
547 | args->out.numargs * sizeof(struct fuse_arg)); | |
548 | fuse_request_send(fc, req); | |
549 | ret = req->out.h.error; | |
550 | if (!ret && args->out.argvar) { | |
551 | BUG_ON(args->out.numargs != 1); | |
552 | ret = req->out.args[0].size; | |
553 | } | |
554 | fuse_put_request(fc, req); | |
555 | ||
556 | return ret; | |
557 | } | |
558 | ||
f0139aa8 MS |
559 | /* |
560 | * Called under fc->lock | |
561 | * | |
562 | * fc->connected must have been checked previously | |
563 | */ | |
564 | void fuse_request_send_background_locked(struct fuse_conn *fc, | |
565 | struct fuse_req *req) | |
d12def1b | 566 | { |
825d6d33 MS |
567 | BUG_ON(!test_bit(FR_BACKGROUND, &req->flags)); |
568 | if (!test_bit(FR_WAITING, &req->flags)) { | |
569 | __set_bit(FR_WAITING, &req->flags); | |
5437f241 MS |
570 | atomic_inc(&fc->num_waiting); |
571 | } | |
825d6d33 | 572 | __set_bit(FR_ISREPLY, &req->flags); |
d12def1b | 573 | fc->num_background++; |
7a6d3c8b | 574 | if (fc->num_background == fc->max_background) |
d12def1b | 575 | fc->blocked = 1; |
7fbbe972 | 576 | if (fc->num_background == fc->congestion_threshold && fc->sb) { |
5f7f7543 JK |
577 | set_bdi_congested(fc->sb->s_bdi, BLK_RW_SYNC); |
578 | set_bdi_congested(fc->sb->s_bdi, BLK_RW_ASYNC); | |
d12def1b MS |
579 | } |
580 | list_add_tail(&req->list, &fc->bg_queue); | |
581 | flush_bg_queue(fc); | |
582 | } | |
583 | ||
f0139aa8 | 584 | void fuse_request_send_background(struct fuse_conn *fc, struct fuse_req *req) |
334f485d | 585 | { |
42dc6211 | 586 | BUG_ON(!req->end); |
d7133114 | 587 | spin_lock(&fc->lock); |
1e9a4ed9 | 588 | if (fc->connected) { |
f0139aa8 | 589 | fuse_request_send_background_locked(fc, req); |
d7133114 | 590 | spin_unlock(&fc->lock); |
334f485d | 591 | } else { |
42dc6211 | 592 | spin_unlock(&fc->lock); |
334f485d | 593 | req->out.h.error = -ENOTCONN; |
42dc6211 MS |
594 | req->end(fc, req); |
595 | fuse_put_request(fc, req); | |
334f485d MS |
596 | } |
597 | } | |
08cbf542 | 598 | EXPORT_SYMBOL_GPL(fuse_request_send_background); |
334f485d | 599 | |
2d45ba38 MS |
600 | static int fuse_request_send_notify_reply(struct fuse_conn *fc, |
601 | struct fuse_req *req, u64 unique) | |
602 | { | |
603 | int err = -ENODEV; | |
f88996a9 | 604 | struct fuse_iqueue *fiq = &fc->iq; |
2d45ba38 | 605 | |
825d6d33 | 606 | __clear_bit(FR_ISREPLY, &req->flags); |
2d45ba38 | 607 | req->in.h.unique = unique; |
4ce60812 | 608 | spin_lock(&fiq->waitq.lock); |
e16714d8 | 609 | if (fiq->connected) { |
f88996a9 | 610 | queue_request(fiq, req); |
2d45ba38 MS |
611 | err = 0; |
612 | } | |
4ce60812 | 613 | spin_unlock(&fiq->waitq.lock); |
2d45ba38 MS |
614 | |
615 | return err; | |
616 | } | |
617 | ||
0b05b183 AA |
618 | void fuse_force_forget(struct file *file, u64 nodeid) |
619 | { | |
6131ffaa | 620 | struct inode *inode = file_inode(file); |
0b05b183 AA |
621 | struct fuse_conn *fc = get_fuse_conn(inode); |
622 | struct fuse_req *req; | |
623 | struct fuse_forget_in inarg; | |
624 | ||
625 | memset(&inarg, 0, sizeof(inarg)); | |
626 | inarg.nlookup = 1; | |
b111c8c0 | 627 | req = fuse_get_req_nofail_nopages(fc, file); |
0b05b183 AA |
628 | req->in.h.opcode = FUSE_FORGET; |
629 | req->in.h.nodeid = nodeid; | |
630 | req->in.numargs = 1; | |
631 | req->in.args[0].size = sizeof(inarg); | |
632 | req->in.args[0].value = &inarg; | |
825d6d33 | 633 | __clear_bit(FR_ISREPLY, &req->flags); |
6a4e922c EW |
634 | __fuse_request_send(fc, req); |
635 | /* ignore errors */ | |
636 | fuse_put_request(fc, req); | |
0b05b183 AA |
637 | } |
638 | ||
334f485d MS |
639 | /* |
640 | * Lock the request. Up to the next unlock_request() there mustn't be | |
641 | * anything that could cause a page-fault. If the request was already | |
f9a2842e | 642 | * aborted bail out. |
334f485d | 643 | */ |
dc00809a | 644 | static int lock_request(struct fuse_req *req) |
334f485d MS |
645 | { |
646 | int err = 0; | |
647 | if (req) { | |
dc00809a | 648 | spin_lock(&req->waitq.lock); |
825d6d33 | 649 | if (test_bit(FR_ABORTED, &req->flags)) |
334f485d MS |
650 | err = -ENOENT; |
651 | else | |
825d6d33 | 652 | set_bit(FR_LOCKED, &req->flags); |
dc00809a | 653 | spin_unlock(&req->waitq.lock); |
334f485d MS |
654 | } |
655 | return err; | |
656 | } | |
657 | ||
658 | /* | |
0d8e84b0 MS |
659 | * Unlock request. If it was aborted while locked, caller is responsible |
660 | * for unlocking and ending the request. | |
334f485d | 661 | */ |
dc00809a | 662 | static int unlock_request(struct fuse_req *req) |
334f485d | 663 | { |
0d8e84b0 | 664 | int err = 0; |
334f485d | 665 | if (req) { |
dc00809a | 666 | spin_lock(&req->waitq.lock); |
825d6d33 | 667 | if (test_bit(FR_ABORTED, &req->flags)) |
0d8e84b0 MS |
668 | err = -ENOENT; |
669 | else | |
825d6d33 | 670 | clear_bit(FR_LOCKED, &req->flags); |
dc00809a | 671 | spin_unlock(&req->waitq.lock); |
334f485d | 672 | } |
0d8e84b0 | 673 | return err; |
334f485d MS |
674 | } |
675 | ||
676 | struct fuse_copy_state { | |
677 | int write; | |
678 | struct fuse_req *req; | |
6c09e94a | 679 | struct iov_iter *iter; |
dd3bb14f MS |
680 | struct pipe_buffer *pipebufs; |
681 | struct pipe_buffer *currbuf; | |
682 | struct pipe_inode_info *pipe; | |
334f485d | 683 | unsigned long nr_segs; |
334f485d | 684 | struct page *pg; |
334f485d | 685 | unsigned len; |
c55a01d3 | 686 | unsigned offset; |
ce534fb0 | 687 | unsigned move_pages:1; |
334f485d MS |
688 | }; |
689 | ||
dc00809a | 690 | static void fuse_copy_init(struct fuse_copy_state *cs, int write, |
6c09e94a | 691 | struct iov_iter *iter) |
334f485d MS |
692 | { |
693 | memset(cs, 0, sizeof(*cs)); | |
694 | cs->write = write; | |
6c09e94a | 695 | cs->iter = iter; |
334f485d MS |
696 | } |
697 | ||
698 | /* Unmap and put previous page of userspace buffer */ | |
8bfc016d | 699 | static void fuse_copy_finish(struct fuse_copy_state *cs) |
334f485d | 700 | { |
dd3bb14f MS |
701 | if (cs->currbuf) { |
702 | struct pipe_buffer *buf = cs->currbuf; | |
703 | ||
c55a01d3 | 704 | if (cs->write) |
c3021629 | 705 | buf->len = PAGE_SIZE - cs->len; |
dd3bb14f | 706 | cs->currbuf = NULL; |
c55a01d3 | 707 | } else if (cs->pg) { |
334f485d MS |
708 | if (cs->write) { |
709 | flush_dcache_page(cs->pg); | |
710 | set_page_dirty_lock(cs->pg); | |
711 | } | |
712 | put_page(cs->pg); | |
334f485d | 713 | } |
c55a01d3 | 714 | cs->pg = NULL; |
334f485d MS |
715 | } |
716 | ||
717 | /* | |
718 | * Get another pagefull of userspace buffer, and map it to kernel | |
719 | * address space, and lock request | |
720 | */ | |
721 | static int fuse_copy_fill(struct fuse_copy_state *cs) | |
722 | { | |
c55a01d3 | 723 | struct page *page; |
334f485d MS |
724 | int err; |
725 | ||
dc00809a | 726 | err = unlock_request(cs->req); |
0d8e84b0 MS |
727 | if (err) |
728 | return err; | |
729 | ||
334f485d | 730 | fuse_copy_finish(cs); |
dd3bb14f MS |
731 | if (cs->pipebufs) { |
732 | struct pipe_buffer *buf = cs->pipebufs; | |
733 | ||
c3021629 | 734 | if (!cs->write) { |
fba597db | 735 | err = pipe_buf_confirm(cs->pipe, buf); |
c3021629 MS |
736 | if (err) |
737 | return err; | |
738 | ||
739 | BUG_ON(!cs->nr_segs); | |
740 | cs->currbuf = buf; | |
c55a01d3 MS |
741 | cs->pg = buf->page; |
742 | cs->offset = buf->offset; | |
c3021629 | 743 | cs->len = buf->len; |
c3021629 MS |
744 | cs->pipebufs++; |
745 | cs->nr_segs--; | |
746 | } else { | |
c3021629 MS |
747 | if (cs->nr_segs == cs->pipe->buffers) |
748 | return -EIO; | |
749 | ||
750 | page = alloc_page(GFP_HIGHUSER); | |
751 | if (!page) | |
752 | return -ENOMEM; | |
753 | ||
754 | buf->page = page; | |
755 | buf->offset = 0; | |
756 | buf->len = 0; | |
757 | ||
758 | cs->currbuf = buf; | |
c55a01d3 MS |
759 | cs->pg = page; |
760 | cs->offset = 0; | |
c3021629 MS |
761 | cs->len = PAGE_SIZE; |
762 | cs->pipebufs++; | |
763 | cs->nr_segs++; | |
764 | } | |
dd3bb14f | 765 | } else { |
6c09e94a AV |
766 | size_t off; |
767 | err = iov_iter_get_pages(cs->iter, &page, PAGE_SIZE, 1, &off); | |
dd3bb14f MS |
768 | if (err < 0) |
769 | return err; | |
6c09e94a AV |
770 | BUG_ON(!err); |
771 | cs->len = err; | |
772 | cs->offset = off; | |
c55a01d3 | 773 | cs->pg = page; |
6c09e94a | 774 | iov_iter_advance(cs->iter, err); |
334f485d | 775 | } |
334f485d | 776 | |
dc00809a | 777 | return lock_request(cs->req); |
334f485d MS |
778 | } |
779 | ||
780 | /* Do as much copy to/from userspace buffer as we can */ | |
8bfc016d | 781 | static int fuse_copy_do(struct fuse_copy_state *cs, void **val, unsigned *size) |
334f485d MS |
782 | { |
783 | unsigned ncpy = min(*size, cs->len); | |
784 | if (val) { | |
c55a01d3 MS |
785 | void *pgaddr = kmap_atomic(cs->pg); |
786 | void *buf = pgaddr + cs->offset; | |
787 | ||
334f485d | 788 | if (cs->write) |
c55a01d3 | 789 | memcpy(buf, *val, ncpy); |
334f485d | 790 | else |
c55a01d3 MS |
791 | memcpy(*val, buf, ncpy); |
792 | ||
793 | kunmap_atomic(pgaddr); | |
334f485d MS |
794 | *val += ncpy; |
795 | } | |
796 | *size -= ncpy; | |
797 | cs->len -= ncpy; | |
c55a01d3 | 798 | cs->offset += ncpy; |
334f485d MS |
799 | return ncpy; |
800 | } | |
801 | ||
ce534fb0 MS |
802 | static int fuse_check_page(struct page *page) |
803 | { | |
804 | if (page_mapcount(page) || | |
805 | page->mapping != NULL || | |
806 | page_count(page) != 1 || | |
807 | (page->flags & PAGE_FLAGS_CHECK_AT_PREP & | |
808 | ~(1 << PG_locked | | |
809 | 1 << PG_referenced | | |
810 | 1 << PG_uptodate | | |
811 | 1 << PG_lru | | |
812 | 1 << PG_active | | |
813 | 1 << PG_reclaim))) { | |
814 | printk(KERN_WARNING "fuse: trying to steal weird page\n"); | |
815 | printk(KERN_WARNING " page=%p index=%li flags=%08lx, count=%i, mapcount=%i, mapping=%p\n", page, page->index, page->flags, page_count(page), page_mapcount(page), page->mapping); | |
816 | return 1; | |
817 | } | |
818 | return 0; | |
819 | } | |
820 | ||
821 | static int fuse_try_move_page(struct fuse_copy_state *cs, struct page **pagep) | |
822 | { | |
823 | int err; | |
824 | struct page *oldpage = *pagep; | |
825 | struct page *newpage; | |
826 | struct pipe_buffer *buf = cs->pipebufs; | |
ce534fb0 | 827 | |
dc00809a | 828 | err = unlock_request(cs->req); |
0d8e84b0 MS |
829 | if (err) |
830 | return err; | |
831 | ||
ce534fb0 MS |
832 | fuse_copy_finish(cs); |
833 | ||
fba597db | 834 | err = pipe_buf_confirm(cs->pipe, buf); |
ce534fb0 MS |
835 | if (err) |
836 | return err; | |
837 | ||
838 | BUG_ON(!cs->nr_segs); | |
839 | cs->currbuf = buf; | |
840 | cs->len = buf->len; | |
841 | cs->pipebufs++; | |
842 | cs->nr_segs--; | |
843 | ||
844 | if (cs->len != PAGE_SIZE) | |
845 | goto out_fallback; | |
846 | ||
ca76f5b6 | 847 | if (pipe_buf_steal(cs->pipe, buf) != 0) |
ce534fb0 MS |
848 | goto out_fallback; |
849 | ||
850 | newpage = buf->page; | |
851 | ||
aa991b3b MS |
852 | if (!PageUptodate(newpage)) |
853 | SetPageUptodate(newpage); | |
ce534fb0 MS |
854 | |
855 | ClearPageMappedToDisk(newpage); | |
856 | ||
857 | if (fuse_check_page(newpage) != 0) | |
858 | goto out_fallback_unlock; | |
859 | ||
ce534fb0 MS |
860 | /* |
861 | * This is a new and locked page, it shouldn't be mapped or | |
862 | * have any special flags on it | |
863 | */ | |
864 | if (WARN_ON(page_mapped(oldpage))) | |
865 | goto out_fallback_unlock; | |
866 | if (WARN_ON(page_has_private(oldpage))) | |
867 | goto out_fallback_unlock; | |
868 | if (WARN_ON(PageDirty(oldpage) || PageWriteback(oldpage))) | |
869 | goto out_fallback_unlock; | |
870 | if (WARN_ON(PageMlocked(oldpage))) | |
871 | goto out_fallback_unlock; | |
872 | ||
ef6a3c63 | 873 | err = replace_page_cache_page(oldpage, newpage, GFP_KERNEL); |
ce534fb0 | 874 | if (err) { |
ef6a3c63 MS |
875 | unlock_page(newpage); |
876 | return err; | |
ce534fb0 | 877 | } |
ef6a3c63 | 878 | |
09cbfeaf | 879 | get_page(newpage); |
ce534fb0 MS |
880 | |
881 | if (!(buf->flags & PIPE_BUF_FLAG_LRU)) | |
882 | lru_cache_add_file(newpage); | |
883 | ||
884 | err = 0; | |
dc00809a | 885 | spin_lock(&cs->req->waitq.lock); |
825d6d33 | 886 | if (test_bit(FR_ABORTED, &cs->req->flags)) |
ce534fb0 MS |
887 | err = -ENOENT; |
888 | else | |
889 | *pagep = newpage; | |
dc00809a | 890 | spin_unlock(&cs->req->waitq.lock); |
ce534fb0 MS |
891 | |
892 | if (err) { | |
893 | unlock_page(newpage); | |
09cbfeaf | 894 | put_page(newpage); |
ce534fb0 MS |
895 | return err; |
896 | } | |
897 | ||
898 | unlock_page(oldpage); | |
09cbfeaf | 899 | put_page(oldpage); |
ce534fb0 MS |
900 | cs->len = 0; |
901 | ||
902 | return 0; | |
903 | ||
904 | out_fallback_unlock: | |
905 | unlock_page(newpage); | |
906 | out_fallback: | |
c55a01d3 MS |
907 | cs->pg = buf->page; |
908 | cs->offset = buf->offset; | |
ce534fb0 | 909 | |
dc00809a | 910 | err = lock_request(cs->req); |
ce534fb0 MS |
911 | if (err) |
912 | return err; | |
913 | ||
914 | return 1; | |
915 | } | |
916 | ||
c3021629 MS |
917 | static int fuse_ref_page(struct fuse_copy_state *cs, struct page *page, |
918 | unsigned offset, unsigned count) | |
919 | { | |
920 | struct pipe_buffer *buf; | |
0d8e84b0 | 921 | int err; |
c3021629 MS |
922 | |
923 | if (cs->nr_segs == cs->pipe->buffers) | |
924 | return -EIO; | |
925 | ||
dc00809a | 926 | err = unlock_request(cs->req); |
0d8e84b0 MS |
927 | if (err) |
928 | return err; | |
929 | ||
c3021629 MS |
930 | fuse_copy_finish(cs); |
931 | ||
932 | buf = cs->pipebufs; | |
09cbfeaf | 933 | get_page(page); |
c3021629 MS |
934 | buf->page = page; |
935 | buf->offset = offset; | |
936 | buf->len = count; | |
937 | ||
938 | cs->pipebufs++; | |
939 | cs->nr_segs++; | |
940 | cs->len = 0; | |
941 | ||
942 | return 0; | |
943 | } | |
944 | ||
334f485d MS |
945 | /* |
946 | * Copy a page in the request to/from the userspace buffer. Must be | |
947 | * done atomically | |
948 | */ | |
ce534fb0 | 949 | static int fuse_copy_page(struct fuse_copy_state *cs, struct page **pagep, |
8bfc016d | 950 | unsigned offset, unsigned count, int zeroing) |
334f485d | 951 | { |
ce534fb0 MS |
952 | int err; |
953 | struct page *page = *pagep; | |
954 | ||
b6777c40 MS |
955 | if (page && zeroing && count < PAGE_SIZE) |
956 | clear_highpage(page); | |
957 | ||
334f485d | 958 | while (count) { |
c3021629 MS |
959 | if (cs->write && cs->pipebufs && page) { |
960 | return fuse_ref_page(cs, page, offset, count); | |
961 | } else if (!cs->len) { | |
ce534fb0 MS |
962 | if (cs->move_pages && page && |
963 | offset == 0 && count == PAGE_SIZE) { | |
964 | err = fuse_try_move_page(cs, pagep); | |
965 | if (err <= 0) | |
966 | return err; | |
967 | } else { | |
968 | err = fuse_copy_fill(cs); | |
969 | if (err) | |
970 | return err; | |
971 | } | |
1729a16c | 972 | } |
334f485d | 973 | if (page) { |
2408f6ef | 974 | void *mapaddr = kmap_atomic(page); |
334f485d MS |
975 | void *buf = mapaddr + offset; |
976 | offset += fuse_copy_do(cs, &buf, &count); | |
2408f6ef | 977 | kunmap_atomic(mapaddr); |
334f485d MS |
978 | } else |
979 | offset += fuse_copy_do(cs, NULL, &count); | |
980 | } | |
981 | if (page && !cs->write) | |
982 | flush_dcache_page(page); | |
983 | return 0; | |
984 | } | |
985 | ||
986 | /* Copy pages in the request to/from userspace buffer */ | |
987 | static int fuse_copy_pages(struct fuse_copy_state *cs, unsigned nbytes, | |
988 | int zeroing) | |
989 | { | |
990 | unsigned i; | |
991 | struct fuse_req *req = cs->req; | |
334f485d MS |
992 | |
993 | for (i = 0; i < req->num_pages && (nbytes || zeroing); i++) { | |
ce534fb0 | 994 | int err; |
85f40aec MP |
995 | unsigned offset = req->page_descs[i].offset; |
996 | unsigned count = min(nbytes, req->page_descs[i].length); | |
ce534fb0 MS |
997 | |
998 | err = fuse_copy_page(cs, &req->pages[i], offset, count, | |
999 | zeroing); | |
334f485d MS |
1000 | if (err) |
1001 | return err; | |
1002 | ||
1003 | nbytes -= count; | |
334f485d MS |
1004 | } |
1005 | return 0; | |
1006 | } | |
1007 | ||
1008 | /* Copy a single argument in the request to/from userspace buffer */ | |
1009 | static int fuse_copy_one(struct fuse_copy_state *cs, void *val, unsigned size) | |
1010 | { | |
1011 | while (size) { | |
1729a16c MS |
1012 | if (!cs->len) { |
1013 | int err = fuse_copy_fill(cs); | |
1014 | if (err) | |
1015 | return err; | |
1016 | } | |
334f485d MS |
1017 | fuse_copy_do(cs, &val, &size); |
1018 | } | |
1019 | return 0; | |
1020 | } | |
1021 | ||
1022 | /* Copy request arguments to/from userspace buffer */ | |
1023 | static int fuse_copy_args(struct fuse_copy_state *cs, unsigned numargs, | |
1024 | unsigned argpages, struct fuse_arg *args, | |
1025 | int zeroing) | |
1026 | { | |
1027 | int err = 0; | |
1028 | unsigned i; | |
1029 | ||
1030 | for (i = 0; !err && i < numargs; i++) { | |
1031 | struct fuse_arg *arg = &args[i]; | |
1032 | if (i == numargs - 1 && argpages) | |
1033 | err = fuse_copy_pages(cs, arg->size, zeroing); | |
1034 | else | |
1035 | err = fuse_copy_one(cs, arg->value, arg->size); | |
1036 | } | |
1037 | return err; | |
1038 | } | |
1039 | ||
f88996a9 | 1040 | static int forget_pending(struct fuse_iqueue *fiq) |
07e77dca | 1041 | { |
f88996a9 | 1042 | return fiq->forget_list_head.next != NULL; |
07e77dca MS |
1043 | } |
1044 | ||
f88996a9 | 1045 | static int request_pending(struct fuse_iqueue *fiq) |
a4d27e75 | 1046 | { |
f88996a9 MS |
1047 | return !list_empty(&fiq->pending) || !list_empty(&fiq->interrupts) || |
1048 | forget_pending(fiq); | |
a4d27e75 MS |
1049 | } |
1050 | ||
a4d27e75 MS |
1051 | /* |
1052 | * Transfer an interrupt request to userspace | |
1053 | * | |
1054 | * Unlike other requests this is assembled on demand, without a need | |
1055 | * to allocate a separate fuse_req structure. | |
1056 | * | |
fd22d62e | 1057 | * Called with fiq->waitq.lock held, releases it |
a4d27e75 | 1058 | */ |
fd22d62e MS |
1059 | static int fuse_read_interrupt(struct fuse_iqueue *fiq, |
1060 | struct fuse_copy_state *cs, | |
c3021629 | 1061 | size_t nbytes, struct fuse_req *req) |
fd22d62e | 1062 | __releases(fiq->waitq.lock) |
a4d27e75 | 1063 | { |
a4d27e75 MS |
1064 | struct fuse_in_header ih; |
1065 | struct fuse_interrupt_in arg; | |
1066 | unsigned reqsize = sizeof(ih) + sizeof(arg); | |
1067 | int err; | |
1068 | ||
1069 | list_del_init(&req->intr_entry); | |
4ce60812 | 1070 | req->intr_unique = fuse_get_unique(fiq); |
a4d27e75 MS |
1071 | memset(&ih, 0, sizeof(ih)); |
1072 | memset(&arg, 0, sizeof(arg)); | |
1073 | ih.len = reqsize; | |
1074 | ih.opcode = FUSE_INTERRUPT; | |
1075 | ih.unique = req->intr_unique; | |
1076 | arg.unique = req->in.h.unique; | |
1077 | ||
4ce60812 | 1078 | spin_unlock(&fiq->waitq.lock); |
c3021629 | 1079 | if (nbytes < reqsize) |
a4d27e75 MS |
1080 | return -EINVAL; |
1081 | ||
c3021629 | 1082 | err = fuse_copy_one(cs, &ih, sizeof(ih)); |
a4d27e75 | 1083 | if (!err) |
c3021629 MS |
1084 | err = fuse_copy_one(cs, &arg, sizeof(arg)); |
1085 | fuse_copy_finish(cs); | |
a4d27e75 MS |
1086 | |
1087 | return err ? err : reqsize; | |
1088 | } | |
1089 | ||
f88996a9 | 1090 | static struct fuse_forget_link *dequeue_forget(struct fuse_iqueue *fiq, |
02c048b9 MS |
1091 | unsigned max, |
1092 | unsigned *countp) | |
07e77dca | 1093 | { |
f88996a9 | 1094 | struct fuse_forget_link *head = fiq->forget_list_head.next; |
02c048b9 MS |
1095 | struct fuse_forget_link **newhead = &head; |
1096 | unsigned count; | |
07e77dca | 1097 | |
02c048b9 MS |
1098 | for (count = 0; *newhead != NULL && count < max; count++) |
1099 | newhead = &(*newhead)->next; | |
1100 | ||
f88996a9 | 1101 | fiq->forget_list_head.next = *newhead; |
02c048b9 | 1102 | *newhead = NULL; |
f88996a9 MS |
1103 | if (fiq->forget_list_head.next == NULL) |
1104 | fiq->forget_list_tail = &fiq->forget_list_head; | |
07e77dca | 1105 | |
02c048b9 MS |
1106 | if (countp != NULL) |
1107 | *countp = count; | |
1108 | ||
1109 | return head; | |
07e77dca MS |
1110 | } |
1111 | ||
fd22d62e | 1112 | static int fuse_read_single_forget(struct fuse_iqueue *fiq, |
07e77dca MS |
1113 | struct fuse_copy_state *cs, |
1114 | size_t nbytes) | |
fd22d62e | 1115 | __releases(fiq->waitq.lock) |
07e77dca MS |
1116 | { |
1117 | int err; | |
f88996a9 | 1118 | struct fuse_forget_link *forget = dequeue_forget(fiq, 1, NULL); |
07e77dca | 1119 | struct fuse_forget_in arg = { |
02c048b9 | 1120 | .nlookup = forget->forget_one.nlookup, |
07e77dca MS |
1121 | }; |
1122 | struct fuse_in_header ih = { | |
1123 | .opcode = FUSE_FORGET, | |
02c048b9 | 1124 | .nodeid = forget->forget_one.nodeid, |
f88996a9 | 1125 | .unique = fuse_get_unique(fiq), |
07e77dca MS |
1126 | .len = sizeof(ih) + sizeof(arg), |
1127 | }; | |
1128 | ||
4ce60812 | 1129 | spin_unlock(&fiq->waitq.lock); |
07e77dca MS |
1130 | kfree(forget); |
1131 | if (nbytes < ih.len) | |
1132 | return -EINVAL; | |
1133 | ||
1134 | err = fuse_copy_one(cs, &ih, sizeof(ih)); | |
1135 | if (!err) | |
1136 | err = fuse_copy_one(cs, &arg, sizeof(arg)); | |
1137 | fuse_copy_finish(cs); | |
1138 | ||
1139 | if (err) | |
1140 | return err; | |
1141 | ||
1142 | return ih.len; | |
1143 | } | |
1144 | ||
fd22d62e | 1145 | static int fuse_read_batch_forget(struct fuse_iqueue *fiq, |
02c048b9 | 1146 | struct fuse_copy_state *cs, size_t nbytes) |
fd22d62e | 1147 | __releases(fiq->waitq.lock) |
02c048b9 MS |
1148 | { |
1149 | int err; | |
1150 | unsigned max_forgets; | |
1151 | unsigned count; | |
1152 | struct fuse_forget_link *head; | |
1153 | struct fuse_batch_forget_in arg = { .count = 0 }; | |
1154 | struct fuse_in_header ih = { | |
1155 | .opcode = FUSE_BATCH_FORGET, | |
f88996a9 | 1156 | .unique = fuse_get_unique(fiq), |
02c048b9 MS |
1157 | .len = sizeof(ih) + sizeof(arg), |
1158 | }; | |
1159 | ||
1160 | if (nbytes < ih.len) { | |
4ce60812 | 1161 | spin_unlock(&fiq->waitq.lock); |
02c048b9 MS |
1162 | return -EINVAL; |
1163 | } | |
1164 | ||
1165 | max_forgets = (nbytes - ih.len) / sizeof(struct fuse_forget_one); | |
f88996a9 | 1166 | head = dequeue_forget(fiq, max_forgets, &count); |
4ce60812 | 1167 | spin_unlock(&fiq->waitq.lock); |
02c048b9 MS |
1168 | |
1169 | arg.count = count; | |
1170 | ih.len += count * sizeof(struct fuse_forget_one); | |
1171 | err = fuse_copy_one(cs, &ih, sizeof(ih)); | |
1172 | if (!err) | |
1173 | err = fuse_copy_one(cs, &arg, sizeof(arg)); | |
1174 | ||
1175 | while (head) { | |
1176 | struct fuse_forget_link *forget = head; | |
1177 | ||
1178 | if (!err) { | |
1179 | err = fuse_copy_one(cs, &forget->forget_one, | |
1180 | sizeof(forget->forget_one)); | |
1181 | } | |
1182 | head = forget->next; | |
1183 | kfree(forget); | |
1184 | } | |
1185 | ||
1186 | fuse_copy_finish(cs); | |
1187 | ||
1188 | if (err) | |
1189 | return err; | |
1190 | ||
1191 | return ih.len; | |
1192 | } | |
1193 | ||
fd22d62e MS |
1194 | static int fuse_read_forget(struct fuse_conn *fc, struct fuse_iqueue *fiq, |
1195 | struct fuse_copy_state *cs, | |
02c048b9 | 1196 | size_t nbytes) |
fd22d62e | 1197 | __releases(fiq->waitq.lock) |
02c048b9 | 1198 | { |
f88996a9 | 1199 | if (fc->minor < 16 || fiq->forget_list_head.next->next == NULL) |
fd22d62e | 1200 | return fuse_read_single_forget(fiq, cs, nbytes); |
02c048b9 | 1201 | else |
fd22d62e | 1202 | return fuse_read_batch_forget(fiq, cs, nbytes); |
02c048b9 MS |
1203 | } |
1204 | ||
334f485d MS |
1205 | /* |
1206 | * Read a single request into the userspace filesystem's buffer. This | |
1207 | * function waits until a request is available, then removes it from | |
1208 | * the pending list and copies request data to userspace buffer. If | |
f9a2842e MS |
1209 | * no reply is needed (FORGET) or request has been aborted or there |
1210 | * was an error during the copying then it's finished by calling | |
334f485d MS |
1211 | * request_end(). Otherwise add it to the processing list, and set |
1212 | * the 'sent' flag. | |
1213 | */ | |
c3696046 | 1214 | static ssize_t fuse_dev_do_read(struct fuse_dev *fud, struct file *file, |
c3021629 | 1215 | struct fuse_copy_state *cs, size_t nbytes) |
334f485d | 1216 | { |
82cbdcd3 | 1217 | ssize_t err; |
c3696046 | 1218 | struct fuse_conn *fc = fud->fc; |
f88996a9 | 1219 | struct fuse_iqueue *fiq = &fc->iq; |
c3696046 | 1220 | struct fuse_pqueue *fpq = &fud->pq; |
334f485d MS |
1221 | struct fuse_req *req; |
1222 | struct fuse_in *in; | |
334f485d MS |
1223 | unsigned reqsize; |
1224 | ||
0b6e9ea0 SF |
1225 | if (task_active_pid_ns(current) != fc->pid_ns) |
1226 | return -EIO; | |
1227 | ||
1d3d752b | 1228 | restart: |
4ce60812 | 1229 | spin_lock(&fiq->waitq.lock); |
e5ac1d1e | 1230 | err = -EAGAIN; |
e16714d8 | 1231 | if ((file->f_flags & O_NONBLOCK) && fiq->connected && |
f88996a9 | 1232 | !request_pending(fiq)) |
e5ac1d1e JD |
1233 | goto err_unlock; |
1234 | ||
5250921b MS |
1235 | err = wait_event_interruptible_exclusive_locked(fiq->waitq, |
1236 | !fiq->connected || request_pending(fiq)); | |
1237 | if (err) | |
1238 | goto err_unlock; | |
1239 | ||
334f485d | 1240 | err = -ENODEV; |
e16714d8 | 1241 | if (!fiq->connected) |
334f485d | 1242 | goto err_unlock; |
334f485d | 1243 | |
f88996a9 MS |
1244 | if (!list_empty(&fiq->interrupts)) { |
1245 | req = list_entry(fiq->interrupts.next, struct fuse_req, | |
a4d27e75 | 1246 | intr_entry); |
fd22d62e | 1247 | return fuse_read_interrupt(fiq, cs, nbytes, req); |
a4d27e75 MS |
1248 | } |
1249 | ||
f88996a9 MS |
1250 | if (forget_pending(fiq)) { |
1251 | if (list_empty(&fiq->pending) || fiq->forget_batch-- > 0) | |
fd22d62e | 1252 | return fuse_read_forget(fc, fiq, cs, nbytes); |
07e77dca | 1253 | |
f88996a9 MS |
1254 | if (fiq->forget_batch <= -8) |
1255 | fiq->forget_batch = 16; | |
07e77dca MS |
1256 | } |
1257 | ||
f88996a9 | 1258 | req = list_entry(fiq->pending.next, struct fuse_req, list); |
33e14b4d | 1259 | clear_bit(FR_PENDING, &req->flags); |
ef759258 | 1260 | list_del_init(&req->list); |
4ce60812 MS |
1261 | spin_unlock(&fiq->waitq.lock); |
1262 | ||
334f485d | 1263 | in = &req->in; |
1d3d752b MS |
1264 | reqsize = in->h.len; |
1265 | /* If request is too large, reply with an error and restart the read */ | |
c3021629 | 1266 | if (nbytes < reqsize) { |
1d3d752b MS |
1267 | req->out.h.error = -EIO; |
1268 | /* SETXATTR is special, since it may contain too large data */ | |
1269 | if (in->h.opcode == FUSE_SETXATTR) | |
1270 | req->out.h.error = -E2BIG; | |
1271 | request_end(fc, req); | |
1272 | goto restart; | |
334f485d | 1273 | } |
45a91cb1 | 1274 | spin_lock(&fpq->lock); |
82cbdcd3 | 1275 | list_add(&req->list, &fpq->io); |
45a91cb1 | 1276 | spin_unlock(&fpq->lock); |
c3021629 MS |
1277 | cs->req = req; |
1278 | err = fuse_copy_one(cs, &in->h, sizeof(in->h)); | |
1d3d752b | 1279 | if (!err) |
c3021629 | 1280 | err = fuse_copy_args(cs, in->numargs, in->argpages, |
1d3d752b | 1281 | (struct fuse_arg *) in->args, 0); |
c3021629 | 1282 | fuse_copy_finish(cs); |
45a91cb1 | 1283 | spin_lock(&fpq->lock); |
825d6d33 | 1284 | clear_bit(FR_LOCKED, &req->flags); |
e96edd94 | 1285 | if (!fpq->connected) { |
82cbdcd3 MS |
1286 | err = -ENODEV; |
1287 | goto out_end; | |
c9c9d7df | 1288 | } |
334f485d | 1289 | if (err) { |
c9c9d7df | 1290 | req->out.h.error = -EIO; |
82cbdcd3 | 1291 | goto out_end; |
334f485d | 1292 | } |
825d6d33 | 1293 | if (!test_bit(FR_ISREPLY, &req->flags)) { |
82cbdcd3 MS |
1294 | err = reqsize; |
1295 | goto out_end; | |
334f485d | 1296 | } |
82cbdcd3 | 1297 | list_move_tail(&req->list, &fpq->processing); |
45a91cb1 | 1298 | spin_unlock(&fpq->lock); |
82cbdcd3 MS |
1299 | set_bit(FR_SENT, &req->flags); |
1300 | /* matches barrier in request_wait_answer() */ | |
1301 | smp_mb__after_atomic(); | |
1302 | if (test_bit(FR_INTERRUPTED, &req->flags)) | |
1303 | queue_interrupt(fiq, req); | |
82cbdcd3 | 1304 | |
334f485d MS |
1305 | return reqsize; |
1306 | ||
82cbdcd3 | 1307 | out_end: |
77cd9d48 MS |
1308 | if (!test_bit(FR_PRIVATE, &req->flags)) |
1309 | list_del_init(&req->list); | |
45a91cb1 | 1310 | spin_unlock(&fpq->lock); |
82cbdcd3 MS |
1311 | request_end(fc, req); |
1312 | return err; | |
1313 | ||
334f485d | 1314 | err_unlock: |
4ce60812 | 1315 | spin_unlock(&fiq->waitq.lock); |
334f485d MS |
1316 | return err; |
1317 | } | |
1318 | ||
94e4fe2c TVB |
1319 | static int fuse_dev_open(struct inode *inode, struct file *file) |
1320 | { | |
1321 | /* | |
1322 | * The fuse device's file's private_data is used to hold | |
1323 | * the fuse_conn(ection) when it is mounted, and is used to | |
1324 | * keep track of whether the file has been mounted already. | |
1325 | */ | |
1326 | file->private_data = NULL; | |
1327 | return 0; | |
1328 | } | |
1329 | ||
fbdbacca | 1330 | static ssize_t fuse_dev_read(struct kiocb *iocb, struct iov_iter *to) |
c3021629 MS |
1331 | { |
1332 | struct fuse_copy_state cs; | |
1333 | struct file *file = iocb->ki_filp; | |
cc080e9e MS |
1334 | struct fuse_dev *fud = fuse_get_dev(file); |
1335 | ||
1336 | if (!fud) | |
c3021629 MS |
1337 | return -EPERM; |
1338 | ||
fbdbacca AV |
1339 | if (!iter_is_iovec(to)) |
1340 | return -EINVAL; | |
1341 | ||
dc00809a | 1342 | fuse_copy_init(&cs, 1, to); |
c3021629 | 1343 | |
c3696046 | 1344 | return fuse_dev_do_read(fud, file, &cs, iov_iter_count(to)); |
c3021629 MS |
1345 | } |
1346 | ||
c3021629 MS |
1347 | static ssize_t fuse_dev_splice_read(struct file *in, loff_t *ppos, |
1348 | struct pipe_inode_info *pipe, | |
1349 | size_t len, unsigned int flags) | |
1350 | { | |
d82718e3 | 1351 | int total, ret; |
c3021629 | 1352 | int page_nr = 0; |
c3021629 MS |
1353 | struct pipe_buffer *bufs; |
1354 | struct fuse_copy_state cs; | |
cc080e9e MS |
1355 | struct fuse_dev *fud = fuse_get_dev(in); |
1356 | ||
1357 | if (!fud) | |
c3021629 MS |
1358 | return -EPERM; |
1359 | ||
07e77dca | 1360 | bufs = kmalloc(pipe->buffers * sizeof(struct pipe_buffer), GFP_KERNEL); |
c3021629 MS |
1361 | if (!bufs) |
1362 | return -ENOMEM; | |
1363 | ||
dc00809a | 1364 | fuse_copy_init(&cs, 1, NULL); |
c3021629 MS |
1365 | cs.pipebufs = bufs; |
1366 | cs.pipe = pipe; | |
c3696046 | 1367 | ret = fuse_dev_do_read(fud, in, &cs, len); |
c3021629 MS |
1368 | if (ret < 0) |
1369 | goto out; | |
1370 | ||
c3021629 MS |
1371 | if (pipe->nrbufs + cs.nr_segs > pipe->buffers) { |
1372 | ret = -EIO; | |
d82718e3 | 1373 | goto out; |
c3021629 MS |
1374 | } |
1375 | ||
d82718e3 | 1376 | for (ret = total = 0; page_nr < cs.nr_segs; total += ret) { |
28a625cb MS |
1377 | /* |
1378 | * Need to be careful about this. Having buf->ops in module | |
1379 | * code can Oops if the buffer persists after module unload. | |
1380 | */ | |
d82718e3 | 1381 | bufs[page_nr].ops = &nosteal_pipe_buf_ops; |
84588a93 | 1382 | bufs[page_nr].flags = 0; |
d82718e3 AV |
1383 | ret = add_to_pipe(pipe, &bufs[page_nr++]); |
1384 | if (unlikely(ret < 0)) | |
1385 | break; | |
c3021629 | 1386 | } |
d82718e3 AV |
1387 | if (total) |
1388 | ret = total; | |
c3021629 MS |
1389 | out: |
1390 | for (; page_nr < cs.nr_segs; page_nr++) | |
09cbfeaf | 1391 | put_page(bufs[page_nr].page); |
c3021629 MS |
1392 | |
1393 | kfree(bufs); | |
1394 | return ret; | |
1395 | } | |
1396 | ||
95668a69 TH |
1397 | static int fuse_notify_poll(struct fuse_conn *fc, unsigned int size, |
1398 | struct fuse_copy_state *cs) | |
1399 | { | |
1400 | struct fuse_notify_poll_wakeup_out outarg; | |
f6d47a17 | 1401 | int err = -EINVAL; |
95668a69 TH |
1402 | |
1403 | if (size != sizeof(outarg)) | |
f6d47a17 | 1404 | goto err; |
95668a69 TH |
1405 | |
1406 | err = fuse_copy_one(cs, &outarg, sizeof(outarg)); | |
1407 | if (err) | |
f6d47a17 | 1408 | goto err; |
95668a69 | 1409 | |
f6d47a17 | 1410 | fuse_copy_finish(cs); |
95668a69 | 1411 | return fuse_notify_poll_wakeup(fc, &outarg); |
f6d47a17 MS |
1412 | |
1413 | err: | |
1414 | fuse_copy_finish(cs); | |
1415 | return err; | |
95668a69 TH |
1416 | } |
1417 | ||
3b463ae0 JM |
1418 | static int fuse_notify_inval_inode(struct fuse_conn *fc, unsigned int size, |
1419 | struct fuse_copy_state *cs) | |
1420 | { | |
1421 | struct fuse_notify_inval_inode_out outarg; | |
1422 | int err = -EINVAL; | |
1423 | ||
1424 | if (size != sizeof(outarg)) | |
1425 | goto err; | |
1426 | ||
1427 | err = fuse_copy_one(cs, &outarg, sizeof(outarg)); | |
1428 | if (err) | |
1429 | goto err; | |
1430 | fuse_copy_finish(cs); | |
1431 | ||
1432 | down_read(&fc->killsb); | |
1433 | err = -ENOENT; | |
b21dda43 MS |
1434 | if (fc->sb) { |
1435 | err = fuse_reverse_inval_inode(fc->sb, outarg.ino, | |
1436 | outarg.off, outarg.len); | |
1437 | } | |
3b463ae0 JM |
1438 | up_read(&fc->killsb); |
1439 | return err; | |
1440 | ||
1441 | err: | |
1442 | fuse_copy_finish(cs); | |
1443 | return err; | |
1444 | } | |
1445 | ||
1446 | static int fuse_notify_inval_entry(struct fuse_conn *fc, unsigned int size, | |
1447 | struct fuse_copy_state *cs) | |
1448 | { | |
1449 | struct fuse_notify_inval_entry_out outarg; | |
b2d82ee3 FW |
1450 | int err = -ENOMEM; |
1451 | char *buf; | |
3b463ae0 JM |
1452 | struct qstr name; |
1453 | ||
b2d82ee3 FW |
1454 | buf = kzalloc(FUSE_NAME_MAX + 1, GFP_KERNEL); |
1455 | if (!buf) | |
1456 | goto err; | |
1457 | ||
1458 | err = -EINVAL; | |
3b463ae0 JM |
1459 | if (size < sizeof(outarg)) |
1460 | goto err; | |
1461 | ||
1462 | err = fuse_copy_one(cs, &outarg, sizeof(outarg)); | |
1463 | if (err) | |
1464 | goto err; | |
1465 | ||
1466 | err = -ENAMETOOLONG; | |
1467 | if (outarg.namelen > FUSE_NAME_MAX) | |
1468 | goto err; | |
1469 | ||
c2183d1e MS |
1470 | err = -EINVAL; |
1471 | if (size != sizeof(outarg) + outarg.namelen + 1) | |
1472 | goto err; | |
1473 | ||
3b463ae0 JM |
1474 | name.name = buf; |
1475 | name.len = outarg.namelen; | |
1476 | err = fuse_copy_one(cs, buf, outarg.namelen + 1); | |
1477 | if (err) | |
1478 | goto err; | |
1479 | fuse_copy_finish(cs); | |
1480 | buf[outarg.namelen] = 0; | |
3b463ae0 JM |
1481 | |
1482 | down_read(&fc->killsb); | |
1483 | err = -ENOENT; | |
b21dda43 | 1484 | if (fc->sb) |
451d0f59 JM |
1485 | err = fuse_reverse_inval_entry(fc->sb, outarg.parent, 0, &name); |
1486 | up_read(&fc->killsb); | |
1487 | kfree(buf); | |
1488 | return err; | |
1489 | ||
1490 | err: | |
1491 | kfree(buf); | |
1492 | fuse_copy_finish(cs); | |
1493 | return err; | |
1494 | } | |
1495 | ||
1496 | static int fuse_notify_delete(struct fuse_conn *fc, unsigned int size, | |
1497 | struct fuse_copy_state *cs) | |
1498 | { | |
1499 | struct fuse_notify_delete_out outarg; | |
1500 | int err = -ENOMEM; | |
1501 | char *buf; | |
1502 | struct qstr name; | |
1503 | ||
1504 | buf = kzalloc(FUSE_NAME_MAX + 1, GFP_KERNEL); | |
1505 | if (!buf) | |
1506 | goto err; | |
1507 | ||
1508 | err = -EINVAL; | |
1509 | if (size < sizeof(outarg)) | |
1510 | goto err; | |
1511 | ||
1512 | err = fuse_copy_one(cs, &outarg, sizeof(outarg)); | |
1513 | if (err) | |
1514 | goto err; | |
1515 | ||
1516 | err = -ENAMETOOLONG; | |
1517 | if (outarg.namelen > FUSE_NAME_MAX) | |
1518 | goto err; | |
1519 | ||
1520 | err = -EINVAL; | |
1521 | if (size != sizeof(outarg) + outarg.namelen + 1) | |
1522 | goto err; | |
1523 | ||
1524 | name.name = buf; | |
1525 | name.len = outarg.namelen; | |
1526 | err = fuse_copy_one(cs, buf, outarg.namelen + 1); | |
1527 | if (err) | |
1528 | goto err; | |
1529 | fuse_copy_finish(cs); | |
1530 | buf[outarg.namelen] = 0; | |
451d0f59 JM |
1531 | |
1532 | down_read(&fc->killsb); | |
1533 | err = -ENOENT; | |
1534 | if (fc->sb) | |
1535 | err = fuse_reverse_inval_entry(fc->sb, outarg.parent, | |
1536 | outarg.child, &name); | |
3b463ae0 | 1537 | up_read(&fc->killsb); |
b2d82ee3 | 1538 | kfree(buf); |
3b463ae0 JM |
1539 | return err; |
1540 | ||
1541 | err: | |
b2d82ee3 | 1542 | kfree(buf); |
3b463ae0 JM |
1543 | fuse_copy_finish(cs); |
1544 | return err; | |
1545 | } | |
1546 | ||
a1d75f25 MS |
1547 | static int fuse_notify_store(struct fuse_conn *fc, unsigned int size, |
1548 | struct fuse_copy_state *cs) | |
1549 | { | |
1550 | struct fuse_notify_store_out outarg; | |
1551 | struct inode *inode; | |
1552 | struct address_space *mapping; | |
1553 | u64 nodeid; | |
1554 | int err; | |
1555 | pgoff_t index; | |
1556 | unsigned int offset; | |
1557 | unsigned int num; | |
1558 | loff_t file_size; | |
1559 | loff_t end; | |
1560 | ||
1561 | err = -EINVAL; | |
1562 | if (size < sizeof(outarg)) | |
1563 | goto out_finish; | |
1564 | ||
1565 | err = fuse_copy_one(cs, &outarg, sizeof(outarg)); | |
1566 | if (err) | |
1567 | goto out_finish; | |
1568 | ||
1569 | err = -EINVAL; | |
1570 | if (size - sizeof(outarg) != outarg.size) | |
1571 | goto out_finish; | |
1572 | ||
1573 | nodeid = outarg.nodeid; | |
1574 | ||
1575 | down_read(&fc->killsb); | |
1576 | ||
1577 | err = -ENOENT; | |
1578 | if (!fc->sb) | |
1579 | goto out_up_killsb; | |
1580 | ||
1581 | inode = ilookup5(fc->sb, nodeid, fuse_inode_eq, &nodeid); | |
1582 | if (!inode) | |
1583 | goto out_up_killsb; | |
1584 | ||
1585 | mapping = inode->i_mapping; | |
09cbfeaf KS |
1586 | index = outarg.offset >> PAGE_SHIFT; |
1587 | offset = outarg.offset & ~PAGE_MASK; | |
a1d75f25 MS |
1588 | file_size = i_size_read(inode); |
1589 | end = outarg.offset + outarg.size; | |
1590 | if (end > file_size) { | |
1591 | file_size = end; | |
1592 | fuse_write_update_size(inode, file_size); | |
1593 | } | |
1594 | ||
1595 | num = outarg.size; | |
1596 | while (num) { | |
1597 | struct page *page; | |
1598 | unsigned int this_num; | |
1599 | ||
1600 | err = -ENOMEM; | |
1601 | page = find_or_create_page(mapping, index, | |
1602 | mapping_gfp_mask(mapping)); | |
1603 | if (!page) | |
1604 | goto out_iput; | |
1605 | ||
09cbfeaf | 1606 | this_num = min_t(unsigned, num, PAGE_SIZE - offset); |
a1d75f25 | 1607 | err = fuse_copy_page(cs, &page, offset, this_num, 0); |
063ec1e5 | 1608 | if (!err && offset == 0 && |
09cbfeaf | 1609 | (this_num == PAGE_SIZE || file_size == end)) |
a1d75f25 MS |
1610 | SetPageUptodate(page); |
1611 | unlock_page(page); | |
09cbfeaf | 1612 | put_page(page); |
a1d75f25 MS |
1613 | |
1614 | if (err) | |
1615 | goto out_iput; | |
1616 | ||
1617 | num -= this_num; | |
1618 | offset = 0; | |
1619 | index++; | |
1620 | } | |
1621 | ||
1622 | err = 0; | |
1623 | ||
1624 | out_iput: | |
1625 | iput(inode); | |
1626 | out_up_killsb: | |
1627 | up_read(&fc->killsb); | |
1628 | out_finish: | |
1629 | fuse_copy_finish(cs); | |
1630 | return err; | |
1631 | } | |
1632 | ||
2d45ba38 MS |
1633 | static void fuse_retrieve_end(struct fuse_conn *fc, struct fuse_req *req) |
1634 | { | |
b745bc85 | 1635 | release_pages(req->pages, req->num_pages, false); |
2d45ba38 MS |
1636 | } |
1637 | ||
1638 | static int fuse_retrieve(struct fuse_conn *fc, struct inode *inode, | |
1639 | struct fuse_notify_retrieve_out *outarg) | |
1640 | { | |
1641 | int err; | |
1642 | struct address_space *mapping = inode->i_mapping; | |
1643 | struct fuse_req *req; | |
1644 | pgoff_t index; | |
1645 | loff_t file_size; | |
1646 | unsigned int num; | |
1647 | unsigned int offset; | |
0157443c | 1648 | size_t total_len = 0; |
4d53dc99 | 1649 | int num_pages; |
2d45ba38 | 1650 | |
09cbfeaf | 1651 | offset = outarg->offset & ~PAGE_MASK; |
4d53dc99 MP |
1652 | file_size = i_size_read(inode); |
1653 | ||
1654 | num = outarg->size; | |
1655 | if (outarg->offset > file_size) | |
1656 | num = 0; | |
1657 | else if (outarg->offset + num > file_size) | |
1658 | num = file_size - outarg->offset; | |
1659 | ||
1660 | num_pages = (num + offset + PAGE_SIZE - 1) >> PAGE_SHIFT; | |
1661 | num_pages = min(num_pages, FUSE_MAX_PAGES_PER_REQ); | |
1662 | ||
1663 | req = fuse_get_req(fc, num_pages); | |
2d45ba38 MS |
1664 | if (IS_ERR(req)) |
1665 | return PTR_ERR(req); | |
1666 | ||
2d45ba38 MS |
1667 | req->in.h.opcode = FUSE_NOTIFY_REPLY; |
1668 | req->in.h.nodeid = outarg->nodeid; | |
1669 | req->in.numargs = 2; | |
1670 | req->in.argpages = 1; | |
b2430d75 | 1671 | req->page_descs[0].offset = offset; |
2d45ba38 MS |
1672 | req->end = fuse_retrieve_end; |
1673 | ||
09cbfeaf | 1674 | index = outarg->offset >> PAGE_SHIFT; |
2d45ba38 | 1675 | |
4d53dc99 | 1676 | while (num && req->num_pages < num_pages) { |
2d45ba38 MS |
1677 | struct page *page; |
1678 | unsigned int this_num; | |
1679 | ||
1680 | page = find_get_page(mapping, index); | |
1681 | if (!page) | |
1682 | break; | |
1683 | ||
09cbfeaf | 1684 | this_num = min_t(unsigned, num, PAGE_SIZE - offset); |
2d45ba38 | 1685 | req->pages[req->num_pages] = page; |
85f40aec | 1686 | req->page_descs[req->num_pages].length = this_num; |
2d45ba38 MS |
1687 | req->num_pages++; |
1688 | ||
c9e67d48 | 1689 | offset = 0; |
2d45ba38 MS |
1690 | num -= this_num; |
1691 | total_len += this_num; | |
48706d0a | 1692 | index++; |
2d45ba38 MS |
1693 | } |
1694 | req->misc.retrieve_in.offset = outarg->offset; | |
1695 | req->misc.retrieve_in.size = total_len; | |
1696 | req->in.args[0].size = sizeof(req->misc.retrieve_in); | |
1697 | req->in.args[0].value = &req->misc.retrieve_in; | |
1698 | req->in.args[1].size = total_len; | |
1699 | ||
1700 | err = fuse_request_send_notify_reply(fc, req, outarg->notify_unique); | |
1701 | if (err) | |
1702 | fuse_retrieve_end(fc, req); | |
1703 | ||
1704 | return err; | |
1705 | } | |
1706 | ||
1707 | static int fuse_notify_retrieve(struct fuse_conn *fc, unsigned int size, | |
1708 | struct fuse_copy_state *cs) | |
1709 | { | |
1710 | struct fuse_notify_retrieve_out outarg; | |
1711 | struct inode *inode; | |
1712 | int err; | |
1713 | ||
1714 | err = -EINVAL; | |
1715 | if (size != sizeof(outarg)) | |
1716 | goto copy_finish; | |
1717 | ||
1718 | err = fuse_copy_one(cs, &outarg, sizeof(outarg)); | |
1719 | if (err) | |
1720 | goto copy_finish; | |
1721 | ||
1722 | fuse_copy_finish(cs); | |
1723 | ||
1724 | down_read(&fc->killsb); | |
1725 | err = -ENOENT; | |
1726 | if (fc->sb) { | |
1727 | u64 nodeid = outarg.nodeid; | |
1728 | ||
1729 | inode = ilookup5(fc->sb, nodeid, fuse_inode_eq, &nodeid); | |
1730 | if (inode) { | |
1731 | err = fuse_retrieve(fc, inode, &outarg); | |
1732 | iput(inode); | |
1733 | } | |
1734 | } | |
1735 | up_read(&fc->killsb); | |
1736 | ||
1737 | return err; | |
1738 | ||
1739 | copy_finish: | |
1740 | fuse_copy_finish(cs); | |
1741 | return err; | |
1742 | } | |
1743 | ||
8599396b TH |
1744 | static int fuse_notify(struct fuse_conn *fc, enum fuse_notify_code code, |
1745 | unsigned int size, struct fuse_copy_state *cs) | |
1746 | { | |
0d278362 MS |
1747 | /* Don't try to move pages (yet) */ |
1748 | cs->move_pages = 0; | |
1749 | ||
8599396b | 1750 | switch (code) { |
95668a69 TH |
1751 | case FUSE_NOTIFY_POLL: |
1752 | return fuse_notify_poll(fc, size, cs); | |
1753 | ||
3b463ae0 JM |
1754 | case FUSE_NOTIFY_INVAL_INODE: |
1755 | return fuse_notify_inval_inode(fc, size, cs); | |
1756 | ||
1757 | case FUSE_NOTIFY_INVAL_ENTRY: | |
1758 | return fuse_notify_inval_entry(fc, size, cs); | |
1759 | ||
a1d75f25 MS |
1760 | case FUSE_NOTIFY_STORE: |
1761 | return fuse_notify_store(fc, size, cs); | |
1762 | ||
2d45ba38 MS |
1763 | case FUSE_NOTIFY_RETRIEVE: |
1764 | return fuse_notify_retrieve(fc, size, cs); | |
1765 | ||
451d0f59 JM |
1766 | case FUSE_NOTIFY_DELETE: |
1767 | return fuse_notify_delete(fc, size, cs); | |
1768 | ||
8599396b | 1769 | default: |
f6d47a17 | 1770 | fuse_copy_finish(cs); |
8599396b TH |
1771 | return -EINVAL; |
1772 | } | |
1773 | } | |
1774 | ||
334f485d | 1775 | /* Look up request on processing list by unique ID */ |
3a2b5b9c | 1776 | static struct fuse_req *request_find(struct fuse_pqueue *fpq, u64 unique) |
334f485d | 1777 | { |
05726aca | 1778 | struct fuse_req *req; |
334f485d | 1779 | |
3a2b5b9c | 1780 | list_for_each_entry(req, &fpq->processing, list) { |
a4d27e75 | 1781 | if (req->in.h.unique == unique || req->intr_unique == unique) |
334f485d MS |
1782 | return req; |
1783 | } | |
1784 | return NULL; | |
1785 | } | |
1786 | ||
1787 | static int copy_out_args(struct fuse_copy_state *cs, struct fuse_out *out, | |
1788 | unsigned nbytes) | |
1789 | { | |
1790 | unsigned reqsize = sizeof(struct fuse_out_header); | |
1791 | ||
1792 | if (out->h.error) | |
1793 | return nbytes != reqsize ? -EINVAL : 0; | |
1794 | ||
1795 | reqsize += len_args(out->numargs, out->args); | |
1796 | ||
1797 | if (reqsize < nbytes || (reqsize > nbytes && !out->argvar)) | |
1798 | return -EINVAL; | |
1799 | else if (reqsize > nbytes) { | |
1800 | struct fuse_arg *lastarg = &out->args[out->numargs-1]; | |
1801 | unsigned diffsize = reqsize - nbytes; | |
1802 | if (diffsize > lastarg->size) | |
1803 | return -EINVAL; | |
1804 | lastarg->size -= diffsize; | |
1805 | } | |
1806 | return fuse_copy_args(cs, out->numargs, out->argpages, out->args, | |
1807 | out->page_zeroing); | |
1808 | } | |
1809 | ||
1810 | /* | |
1811 | * Write a single reply to a request. First the header is copied from | |
1812 | * the write buffer. The request is then searched on the processing | |
1813 | * list by the unique ID found in the header. If found, then remove | |
1814 | * it from the list and copy the rest of the buffer to the request. | |
1815 | * The request is finished by calling request_end() | |
1816 | */ | |
c3696046 | 1817 | static ssize_t fuse_dev_do_write(struct fuse_dev *fud, |
dd3bb14f | 1818 | struct fuse_copy_state *cs, size_t nbytes) |
334f485d MS |
1819 | { |
1820 | int err; | |
c3696046 MS |
1821 | struct fuse_conn *fc = fud->fc; |
1822 | struct fuse_pqueue *fpq = &fud->pq; | |
334f485d MS |
1823 | struct fuse_req *req; |
1824 | struct fuse_out_header oh; | |
334f485d | 1825 | |
0b6e9ea0 SF |
1826 | if (task_active_pid_ns(current) != fc->pid_ns) |
1827 | return -EIO; | |
1828 | ||
334f485d MS |
1829 | if (nbytes < sizeof(struct fuse_out_header)) |
1830 | return -EINVAL; | |
1831 | ||
dd3bb14f | 1832 | err = fuse_copy_one(cs, &oh, sizeof(oh)); |
334f485d MS |
1833 | if (err) |
1834 | goto err_finish; | |
8599396b TH |
1835 | |
1836 | err = -EINVAL; | |
1837 | if (oh.len != nbytes) | |
1838 | goto err_finish; | |
1839 | ||
1840 | /* | |
1841 | * Zero oh.unique indicates unsolicited notification message | |
1842 | * and error contains notification code. | |
1843 | */ | |
1844 | if (!oh.unique) { | |
dd3bb14f | 1845 | err = fuse_notify(fc, oh.error, nbytes - sizeof(oh), cs); |
8599396b TH |
1846 | return err ? err : nbytes; |
1847 | } | |
1848 | ||
334f485d | 1849 | err = -EINVAL; |
8599396b | 1850 | if (oh.error <= -1000 || oh.error > 0) |
334f485d MS |
1851 | goto err_finish; |
1852 | ||
45a91cb1 | 1853 | spin_lock(&fpq->lock); |
69a53bf2 | 1854 | err = -ENOENT; |
e96edd94 | 1855 | if (!fpq->connected) |
45a91cb1 | 1856 | goto err_unlock_pq; |
69a53bf2 | 1857 | |
3a2b5b9c | 1858 | req = request_find(fpq, oh.unique); |
334f485d | 1859 | if (!req) |
45a91cb1 | 1860 | goto err_unlock_pq; |
334f485d | 1861 | |
a4d27e75 MS |
1862 | /* Is it an interrupt reply? */ |
1863 | if (req->intr_unique == oh.unique) { | |
45a91cb1 MS |
1864 | spin_unlock(&fpq->lock); |
1865 | ||
a4d27e75 MS |
1866 | err = -EINVAL; |
1867 | if (nbytes != sizeof(struct fuse_out_header)) | |
46c34a34 | 1868 | goto err_finish; |
a4d27e75 MS |
1869 | |
1870 | if (oh.error == -ENOSYS) | |
1871 | fc->no_interrupt = 1; | |
1872 | else if (oh.error == -EAGAIN) | |
f88996a9 | 1873 | queue_interrupt(&fc->iq, req); |
a4d27e75 | 1874 | |
dd3bb14f | 1875 | fuse_copy_finish(cs); |
a4d27e75 MS |
1876 | return nbytes; |
1877 | } | |
1878 | ||
33e14b4d | 1879 | clear_bit(FR_SENT, &req->flags); |
3a2b5b9c | 1880 | list_move(&req->list, &fpq->io); |
334f485d | 1881 | req->out.h = oh; |
825d6d33 | 1882 | set_bit(FR_LOCKED, &req->flags); |
45a91cb1 | 1883 | spin_unlock(&fpq->lock); |
dd3bb14f | 1884 | cs->req = req; |
ce534fb0 MS |
1885 | if (!req->out.page_replace) |
1886 | cs->move_pages = 0; | |
334f485d | 1887 | |
dd3bb14f MS |
1888 | err = copy_out_args(cs, &req->out, nbytes); |
1889 | fuse_copy_finish(cs); | |
334f485d | 1890 | |
45a91cb1 | 1891 | spin_lock(&fpq->lock); |
825d6d33 | 1892 | clear_bit(FR_LOCKED, &req->flags); |
e96edd94 | 1893 | if (!fpq->connected) |
0d8e84b0 MS |
1894 | err = -ENOENT; |
1895 | else if (err) | |
334f485d | 1896 | req->out.h.error = -EIO; |
77cd9d48 MS |
1897 | if (!test_bit(FR_PRIVATE, &req->flags)) |
1898 | list_del_init(&req->list); | |
45a91cb1 | 1899 | spin_unlock(&fpq->lock); |
46c34a34 | 1900 | |
334f485d MS |
1901 | request_end(fc, req); |
1902 | ||
1903 | return err ? err : nbytes; | |
1904 | ||
45a91cb1 MS |
1905 | err_unlock_pq: |
1906 | spin_unlock(&fpq->lock); | |
334f485d | 1907 | err_finish: |
dd3bb14f | 1908 | fuse_copy_finish(cs); |
334f485d MS |
1909 | return err; |
1910 | } | |
1911 | ||
fbdbacca | 1912 | static ssize_t fuse_dev_write(struct kiocb *iocb, struct iov_iter *from) |
dd3bb14f MS |
1913 | { |
1914 | struct fuse_copy_state cs; | |
cc080e9e MS |
1915 | struct fuse_dev *fud = fuse_get_dev(iocb->ki_filp); |
1916 | ||
1917 | if (!fud) | |
dd3bb14f MS |
1918 | return -EPERM; |
1919 | ||
fbdbacca AV |
1920 | if (!iter_is_iovec(from)) |
1921 | return -EINVAL; | |
1922 | ||
dc00809a | 1923 | fuse_copy_init(&cs, 0, from); |
dd3bb14f | 1924 | |
c3696046 | 1925 | return fuse_dev_do_write(fud, &cs, iov_iter_count(from)); |
dd3bb14f MS |
1926 | } |
1927 | ||
1928 | static ssize_t fuse_dev_splice_write(struct pipe_inode_info *pipe, | |
1929 | struct file *out, loff_t *ppos, | |
1930 | size_t len, unsigned int flags) | |
1931 | { | |
1932 | unsigned nbuf; | |
1933 | unsigned idx; | |
1934 | struct pipe_buffer *bufs; | |
1935 | struct fuse_copy_state cs; | |
cc080e9e | 1936 | struct fuse_dev *fud; |
dd3bb14f MS |
1937 | size_t rem; |
1938 | ssize_t ret; | |
1939 | ||
cc080e9e MS |
1940 | fud = fuse_get_dev(out); |
1941 | if (!fud) | |
dd3bb14f MS |
1942 | return -EPERM; |
1943 | ||
07e77dca | 1944 | bufs = kmalloc(pipe->buffers * sizeof(struct pipe_buffer), GFP_KERNEL); |
dd3bb14f MS |
1945 | if (!bufs) |
1946 | return -ENOMEM; | |
1947 | ||
1948 | pipe_lock(pipe); | |
1949 | nbuf = 0; | |
1950 | rem = 0; | |
1951 | for (idx = 0; idx < pipe->nrbufs && rem < len; idx++) | |
1952 | rem += pipe->bufs[(pipe->curbuf + idx) & (pipe->buffers - 1)].len; | |
1953 | ||
1954 | ret = -EINVAL; | |
1955 | if (rem < len) { | |
1956 | pipe_unlock(pipe); | |
1957 | goto out; | |
1958 | } | |
1959 | ||
1960 | rem = len; | |
1961 | while (rem) { | |
1962 | struct pipe_buffer *ibuf; | |
1963 | struct pipe_buffer *obuf; | |
1964 | ||
1965 | BUG_ON(nbuf >= pipe->buffers); | |
1966 | BUG_ON(!pipe->nrbufs); | |
1967 | ibuf = &pipe->bufs[pipe->curbuf]; | |
1968 | obuf = &bufs[nbuf]; | |
1969 | ||
1970 | if (rem >= ibuf->len) { | |
1971 | *obuf = *ibuf; | |
1972 | ibuf->ops = NULL; | |
1973 | pipe->curbuf = (pipe->curbuf + 1) & (pipe->buffers - 1); | |
1974 | pipe->nrbufs--; | |
1975 | } else { | |
7bf2d1df | 1976 | pipe_buf_get(pipe, ibuf); |
dd3bb14f MS |
1977 | *obuf = *ibuf; |
1978 | obuf->flags &= ~PIPE_BUF_FLAG_GIFT; | |
1979 | obuf->len = rem; | |
1980 | ibuf->offset += obuf->len; | |
1981 | ibuf->len -= obuf->len; | |
1982 | } | |
1983 | nbuf++; | |
1984 | rem -= obuf->len; | |
1985 | } | |
1986 | pipe_unlock(pipe); | |
1987 | ||
dc00809a | 1988 | fuse_copy_init(&cs, 0, NULL); |
dd3bb14f | 1989 | cs.pipebufs = bufs; |
6c09e94a | 1990 | cs.nr_segs = nbuf; |
dd3bb14f MS |
1991 | cs.pipe = pipe; |
1992 | ||
ce534fb0 MS |
1993 | if (flags & SPLICE_F_MOVE) |
1994 | cs.move_pages = 1; | |
1995 | ||
c3696046 | 1996 | ret = fuse_dev_do_write(fud, &cs, len); |
dd3bb14f | 1997 | |
a779638c MS |
1998 | for (idx = 0; idx < nbuf; idx++) |
1999 | pipe_buf_release(pipe, &bufs[idx]); | |
2000 | ||
dd3bb14f MS |
2001 | out: |
2002 | kfree(bufs); | |
2003 | return ret; | |
2004 | } | |
2005 | ||
334f485d MS |
2006 | static unsigned fuse_dev_poll(struct file *file, poll_table *wait) |
2007 | { | |
334f485d | 2008 | unsigned mask = POLLOUT | POLLWRNORM; |
f88996a9 | 2009 | struct fuse_iqueue *fiq; |
cc080e9e MS |
2010 | struct fuse_dev *fud = fuse_get_dev(file); |
2011 | ||
2012 | if (!fud) | |
7025d9ad | 2013 | return POLLERR; |
334f485d | 2014 | |
cc080e9e | 2015 | fiq = &fud->fc->iq; |
f88996a9 | 2016 | poll_wait(file, &fiq->waitq, wait); |
334f485d | 2017 | |
4ce60812 | 2018 | spin_lock(&fiq->waitq.lock); |
e16714d8 | 2019 | if (!fiq->connected) |
7025d9ad | 2020 | mask = POLLERR; |
f88996a9 | 2021 | else if (request_pending(fiq)) |
7025d9ad | 2022 | mask |= POLLIN | POLLRDNORM; |
4ce60812 | 2023 | spin_unlock(&fiq->waitq.lock); |
334f485d MS |
2024 | |
2025 | return mask; | |
2026 | } | |
2027 | ||
69a53bf2 MS |
2028 | /* |
2029 | * Abort all requests on the given list (pending or processing) | |
2030 | * | |
d7133114 | 2031 | * This function releases and reacquires fc->lock |
69a53bf2 | 2032 | */ |
334f485d MS |
2033 | static void end_requests(struct fuse_conn *fc, struct list_head *head) |
2034 | { | |
2035 | while (!list_empty(head)) { | |
2036 | struct fuse_req *req; | |
2037 | req = list_entry(head->next, struct fuse_req, list); | |
334f485d | 2038 | req->out.h.error = -ECONNABORTED; |
33e14b4d | 2039 | clear_bit(FR_SENT, &req->flags); |
f377cb79 | 2040 | list_del_init(&req->list); |
334f485d | 2041 | request_end(fc, req); |
334f485d MS |
2042 | } |
2043 | } | |
2044 | ||
357ccf2b BG |
2045 | static void end_polls(struct fuse_conn *fc) |
2046 | { | |
2047 | struct rb_node *p; | |
2048 | ||
2049 | p = rb_first(&fc->polled_files); | |
2050 | ||
2051 | while (p) { | |
2052 | struct fuse_file *ff; | |
2053 | ff = rb_entry(p, struct fuse_file, polled_node); | |
2054 | wake_up_interruptible_all(&ff->poll_wait); | |
2055 | ||
2056 | p = rb_next(p); | |
2057 | } | |
2058 | } | |
2059 | ||
69a53bf2 MS |
2060 | /* |
2061 | * Abort all requests. | |
2062 | * | |
b716d425 MS |
2063 | * Emergency exit in case of a malicious or accidental deadlock, or just a hung |
2064 | * filesystem. | |
2065 | * | |
2066 | * The same effect is usually achievable through killing the filesystem daemon | |
2067 | * and all users of the filesystem. The exception is the combination of an | |
2068 | * asynchronous request and the tricky deadlock (see | |
2069 | * Documentation/filesystems/fuse.txt). | |
69a53bf2 | 2070 | * |
b716d425 MS |
2071 | * Aborting requests under I/O goes as follows: 1: Separate out unlocked |
2072 | * requests, they should be finished off immediately. Locked requests will be | |
2073 | * finished after unlock; see unlock_request(). 2: Finish off the unlocked | |
2074 | * requests. It is possible that some request will finish before we can. This | |
2075 | * is OK, the request will in that case be removed from the list before we touch | |
2076 | * it. | |
69a53bf2 MS |
2077 | */ |
2078 | void fuse_abort_conn(struct fuse_conn *fc) | |
2079 | { | |
f88996a9 MS |
2080 | struct fuse_iqueue *fiq = &fc->iq; |
2081 | ||
d7133114 | 2082 | spin_lock(&fc->lock); |
69a53bf2 | 2083 | if (fc->connected) { |
c3696046 | 2084 | struct fuse_dev *fud; |
b716d425 | 2085 | struct fuse_req *req, *next; |
41f98274 MS |
2086 | LIST_HEAD(to_end1); |
2087 | LIST_HEAD(to_end2); | |
b716d425 | 2088 | |
69a53bf2 | 2089 | fc->connected = 0; |
51eb01e7 | 2090 | fc->blocked = 0; |
9759bd51 | 2091 | fuse_set_initialized(fc); |
c3696046 MS |
2092 | list_for_each_entry(fud, &fc->devices, entry) { |
2093 | struct fuse_pqueue *fpq = &fud->pq; | |
2094 | ||
2095 | spin_lock(&fpq->lock); | |
2096 | fpq->connected = 0; | |
2097 | list_for_each_entry_safe(req, next, &fpq->io, list) { | |
2098 | req->out.h.error = -ECONNABORTED; | |
2099 | spin_lock(&req->waitq.lock); | |
2100 | set_bit(FR_ABORTED, &req->flags); | |
2101 | if (!test_bit(FR_LOCKED, &req->flags)) { | |
2102 | set_bit(FR_PRIVATE, &req->flags); | |
2103 | list_move(&req->list, &to_end1); | |
2104 | } | |
2105 | spin_unlock(&req->waitq.lock); | |
77cd9d48 | 2106 | } |
c3696046 MS |
2107 | list_splice_init(&fpq->processing, &to_end2); |
2108 | spin_unlock(&fpq->lock); | |
b716d425 | 2109 | } |
41f98274 MS |
2110 | fc->max_background = UINT_MAX; |
2111 | flush_bg_queue(fc); | |
8c91189a | 2112 | |
4ce60812 | 2113 | spin_lock(&fiq->waitq.lock); |
8c91189a | 2114 | fiq->connected = 0; |
f88996a9 | 2115 | list_splice_init(&fiq->pending, &to_end2); |
a8a86d78 TE |
2116 | list_for_each_entry(req, &to_end2, list) |
2117 | clear_bit(FR_PENDING, &req->flags); | |
8c91189a MS |
2118 | while (forget_pending(fiq)) |
2119 | kfree(dequeue_forget(fiq, 1, NULL)); | |
4ce60812 MS |
2120 | wake_up_all_locked(&fiq->waitq); |
2121 | spin_unlock(&fiq->waitq.lock); | |
8c91189a | 2122 | kill_fasync(&fiq->fasync, SIGIO, POLL_IN); |
ee314a87 MS |
2123 | end_polls(fc); |
2124 | wake_up_all(&fc->blocked_waitq); | |
2125 | spin_unlock(&fc->lock); | |
8c91189a | 2126 | |
41f98274 MS |
2127 | while (!list_empty(&to_end1)) { |
2128 | req = list_first_entry(&to_end1, struct fuse_req, list); | |
b716d425 | 2129 | __fuse_get_request(req); |
f377cb79 | 2130 | list_del_init(&req->list); |
b716d425 | 2131 | request_end(fc, req); |
b716d425 | 2132 | } |
41f98274 | 2133 | end_requests(fc, &to_end2); |
ee314a87 MS |
2134 | } else { |
2135 | spin_unlock(&fc->lock); | |
69a53bf2 | 2136 | } |
69a53bf2 | 2137 | } |
08cbf542 | 2138 | EXPORT_SYMBOL_GPL(fuse_abort_conn); |
69a53bf2 | 2139 | |
08cbf542 | 2140 | int fuse_dev_release(struct inode *inode, struct file *file) |
334f485d | 2141 | { |
cc080e9e MS |
2142 | struct fuse_dev *fud = fuse_get_dev(file); |
2143 | ||
2144 | if (fud) { | |
2145 | struct fuse_conn *fc = fud->fc; | |
c3696046 MS |
2146 | struct fuse_pqueue *fpq = &fud->pq; |
2147 | ||
2148 | WARN_ON(!list_empty(&fpq->io)); | |
2149 | end_requests(fc, &fpq->processing); | |
2150 | /* Are we the last open device? */ | |
2151 | if (atomic_dec_and_test(&fc->dev_count)) { | |
2152 | WARN_ON(fc->iq.fasync != NULL); | |
2153 | fuse_abort_conn(fc); | |
2154 | } | |
cc080e9e | 2155 | fuse_dev_free(fud); |
385a17bf | 2156 | } |
334f485d MS |
2157 | return 0; |
2158 | } | |
08cbf542 | 2159 | EXPORT_SYMBOL_GPL(fuse_dev_release); |
334f485d | 2160 | |
385a17bf JD |
2161 | static int fuse_dev_fasync(int fd, struct file *file, int on) |
2162 | { | |
cc080e9e MS |
2163 | struct fuse_dev *fud = fuse_get_dev(file); |
2164 | ||
2165 | if (!fud) | |
a87046d8 | 2166 | return -EPERM; |
385a17bf JD |
2167 | |
2168 | /* No locking - fasync_helper does its own locking */ | |
cc080e9e | 2169 | return fasync_helper(fd, file, on, &fud->fc->iq.fasync); |
385a17bf JD |
2170 | } |
2171 | ||
00c570f4 MS |
2172 | static int fuse_device_clone(struct fuse_conn *fc, struct file *new) |
2173 | { | |
cc080e9e MS |
2174 | struct fuse_dev *fud; |
2175 | ||
00c570f4 MS |
2176 | if (new->private_data) |
2177 | return -EINVAL; | |
2178 | ||
cc080e9e MS |
2179 | fud = fuse_dev_alloc(fc); |
2180 | if (!fud) | |
2181 | return -ENOMEM; | |
2182 | ||
2183 | new->private_data = fud; | |
c3696046 | 2184 | atomic_inc(&fc->dev_count); |
00c570f4 MS |
2185 | |
2186 | return 0; | |
2187 | } | |
2188 | ||
2189 | static long fuse_dev_ioctl(struct file *file, unsigned int cmd, | |
2190 | unsigned long arg) | |
2191 | { | |
2192 | int err = -ENOTTY; | |
2193 | ||
2194 | if (cmd == FUSE_DEV_IOC_CLONE) { | |
2195 | int oldfd; | |
2196 | ||
2197 | err = -EFAULT; | |
2198 | if (!get_user(oldfd, (__u32 __user *) arg)) { | |
2199 | struct file *old = fget(oldfd); | |
2200 | ||
2201 | err = -EINVAL; | |
2202 | if (old) { | |
8ed1f0e2 JH |
2203 | struct fuse_dev *fud = NULL; |
2204 | ||
2205 | /* | |
2206 | * Check against file->f_op because CUSE | |
2207 | * uses the same ioctl handler. | |
2208 | */ | |
2209 | if (old->f_op == file->f_op && | |
2210 | old->f_cred->user_ns == file->f_cred->user_ns) | |
2211 | fud = fuse_get_dev(old); | |
00c570f4 | 2212 | |
cc080e9e | 2213 | if (fud) { |
00c570f4 | 2214 | mutex_lock(&fuse_mutex); |
cc080e9e | 2215 | err = fuse_device_clone(fud->fc, file); |
00c570f4 MS |
2216 | mutex_unlock(&fuse_mutex); |
2217 | } | |
2218 | fput(old); | |
2219 | } | |
2220 | } | |
2221 | } | |
2222 | return err; | |
2223 | } | |
2224 | ||
4b6f5d20 | 2225 | const struct file_operations fuse_dev_operations = { |
334f485d | 2226 | .owner = THIS_MODULE, |
94e4fe2c | 2227 | .open = fuse_dev_open, |
334f485d | 2228 | .llseek = no_llseek, |
fbdbacca | 2229 | .read_iter = fuse_dev_read, |
c3021629 | 2230 | .splice_read = fuse_dev_splice_read, |
fbdbacca | 2231 | .write_iter = fuse_dev_write, |
dd3bb14f | 2232 | .splice_write = fuse_dev_splice_write, |
334f485d MS |
2233 | .poll = fuse_dev_poll, |
2234 | .release = fuse_dev_release, | |
385a17bf | 2235 | .fasync = fuse_dev_fasync, |
00c570f4 MS |
2236 | .unlocked_ioctl = fuse_dev_ioctl, |
2237 | .compat_ioctl = fuse_dev_ioctl, | |
334f485d | 2238 | }; |
08cbf542 | 2239 | EXPORT_SYMBOL_GPL(fuse_dev_operations); |
334f485d MS |
2240 | |
2241 | static struct miscdevice fuse_miscdevice = { | |
2242 | .minor = FUSE_MINOR, | |
2243 | .name = "fuse", | |
2244 | .fops = &fuse_dev_operations, | |
2245 | }; | |
2246 | ||
2247 | int __init fuse_dev_init(void) | |
2248 | { | |
2249 | int err = -ENOMEM; | |
2250 | fuse_req_cachep = kmem_cache_create("fuse_request", | |
2251 | sizeof(struct fuse_req), | |
20c2df83 | 2252 | 0, 0, NULL); |
334f485d MS |
2253 | if (!fuse_req_cachep) |
2254 | goto out; | |
2255 | ||
2256 | err = misc_register(&fuse_miscdevice); | |
2257 | if (err) | |
2258 | goto out_cache_clean; | |
2259 | ||
2260 | return 0; | |
2261 | ||
2262 | out_cache_clean: | |
2263 | kmem_cache_destroy(fuse_req_cachep); | |
2264 | out: | |
2265 | return err; | |
2266 | } | |
2267 | ||
2268 | void fuse_dev_cleanup(void) | |
2269 | { | |
2270 | misc_deregister(&fuse_miscdevice); | |
2271 | kmem_cache_destroy(fuse_req_cachep); | |
2272 | } |