Commit | Line | Data |
---|---|---|
b6aeaded MS |
1 | /* |
2 | FUSE: Filesystem in Userspace | |
1729a16c | 3 | Copyright (C) 2001-2008 Miklos Szeredi <miklos@szeredi.hu> |
b6aeaded 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/pagemap.h> | |
12 | #include <linux/slab.h> | |
13 | #include <linux/kernel.h> | |
e8edc6e0 | 14 | #include <linux/sched.h> |
08cbf542 | 15 | #include <linux/module.h> |
b6aeaded | 16 | |
4b6f5d20 | 17 | static const struct file_operations fuse_direct_io_file_operations; |
45323fb7 | 18 | |
91fe96b4 MS |
19 | static int fuse_send_open(struct fuse_conn *fc, u64 nodeid, struct file *file, |
20 | int opcode, struct fuse_open_out *outargp) | |
b6aeaded | 21 | { |
b6aeaded | 22 | struct fuse_open_in inarg; |
fd72faac MS |
23 | struct fuse_req *req; |
24 | int err; | |
25 | ||
ce1d5a49 MS |
26 | req = fuse_get_req(fc); |
27 | if (IS_ERR(req)) | |
28 | return PTR_ERR(req); | |
fd72faac MS |
29 | |
30 | memset(&inarg, 0, sizeof(inarg)); | |
6ff958ed MS |
31 | inarg.flags = file->f_flags & ~(O_CREAT | O_EXCL | O_NOCTTY); |
32 | if (!fc->atomic_o_trunc) | |
33 | inarg.flags &= ~O_TRUNC; | |
91fe96b4 MS |
34 | req->in.h.opcode = opcode; |
35 | req->in.h.nodeid = nodeid; | |
fd72faac MS |
36 | req->in.numargs = 1; |
37 | req->in.args[0].size = sizeof(inarg); | |
38 | req->in.args[0].value = &inarg; | |
39 | req->out.numargs = 1; | |
40 | req->out.args[0].size = sizeof(*outargp); | |
41 | req->out.args[0].value = outargp; | |
b93f858a | 42 | fuse_request_send(fc, req); |
fd72faac MS |
43 | err = req->out.h.error; |
44 | fuse_put_request(fc, req); | |
45 | ||
46 | return err; | |
47 | } | |
48 | ||
acf99433 | 49 | struct fuse_file *fuse_file_alloc(struct fuse_conn *fc) |
fd72faac MS |
50 | { |
51 | struct fuse_file *ff; | |
6b2db28a | 52 | |
fd72faac | 53 | ff = kmalloc(sizeof(struct fuse_file), GFP_KERNEL); |
6b2db28a TH |
54 | if (unlikely(!ff)) |
55 | return NULL; | |
56 | ||
da5e4714 | 57 | ff->fc = fc; |
6b2db28a TH |
58 | ff->reserved_req = fuse_request_alloc(); |
59 | if (unlikely(!ff->reserved_req)) { | |
60 | kfree(ff); | |
61 | return NULL; | |
fd72faac | 62 | } |
6b2db28a TH |
63 | |
64 | INIT_LIST_HEAD(&ff->write_entry); | |
65 | atomic_set(&ff->count, 0); | |
66 | RB_CLEAR_NODE(&ff->polled_node); | |
67 | init_waitqueue_head(&ff->poll_wait); | |
68 | ||
69 | spin_lock(&fc->lock); | |
70 | ff->kh = ++fc->khctr; | |
71 | spin_unlock(&fc->lock); | |
72 | ||
fd72faac MS |
73 | return ff; |
74 | } | |
75 | ||
76 | void fuse_file_free(struct fuse_file *ff) | |
77 | { | |
33649c91 | 78 | fuse_request_free(ff->reserved_req); |
fd72faac MS |
79 | kfree(ff); |
80 | } | |
81 | ||
c7b7143c | 82 | struct fuse_file *fuse_file_get(struct fuse_file *ff) |
c756e0a4 MS |
83 | { |
84 | atomic_inc(&ff->count); | |
85 | return ff; | |
86 | } | |
87 | ||
819c4b3b MS |
88 | static void fuse_release_end(struct fuse_conn *fc, struct fuse_req *req) |
89 | { | |
b0be46eb | 90 | path_put(&req->misc.release.path); |
819c4b3b MS |
91 | } |
92 | ||
c756e0a4 MS |
93 | static void fuse_file_put(struct fuse_file *ff) |
94 | { | |
95 | if (atomic_dec_and_test(&ff->count)) { | |
96 | struct fuse_req *req = ff->reserved_req; | |
8b0797a4 | 97 | |
819c4b3b | 98 | req->end = fuse_release_end; |
8b0797a4 | 99 | fuse_request_send_background(ff->fc, req); |
c756e0a4 MS |
100 | kfree(ff); |
101 | } | |
102 | } | |
103 | ||
08cbf542 TH |
104 | int fuse_do_open(struct fuse_conn *fc, u64 nodeid, struct file *file, |
105 | bool isdir) | |
91fe96b4 MS |
106 | { |
107 | struct fuse_open_out outarg; | |
108 | struct fuse_file *ff; | |
109 | int err; | |
110 | int opcode = isdir ? FUSE_OPENDIR : FUSE_OPEN; | |
111 | ||
112 | ff = fuse_file_alloc(fc); | |
113 | if (!ff) | |
114 | return -ENOMEM; | |
115 | ||
116 | err = fuse_send_open(fc, nodeid, file, opcode, &outarg); | |
117 | if (err) { | |
118 | fuse_file_free(ff); | |
119 | return err; | |
120 | } | |
121 | ||
122 | if (isdir) | |
123 | outarg.open_flags &= ~FOPEN_DIRECT_IO; | |
124 | ||
125 | ff->fh = outarg.fh; | |
126 | ff->nodeid = nodeid; | |
127 | ff->open_flags = outarg.open_flags; | |
128 | file->private_data = fuse_file_get(ff); | |
129 | ||
130 | return 0; | |
131 | } | |
08cbf542 | 132 | EXPORT_SYMBOL_GPL(fuse_do_open); |
91fe96b4 | 133 | |
c7b7143c | 134 | void fuse_finish_open(struct inode *inode, struct file *file) |
fd72faac | 135 | { |
c7b7143c | 136 | struct fuse_file *ff = file->private_data; |
a0822c55 | 137 | struct fuse_conn *fc = get_fuse_conn(inode); |
c7b7143c MS |
138 | |
139 | if (ff->open_flags & FOPEN_DIRECT_IO) | |
fd72faac | 140 | file->f_op = &fuse_direct_io_file_operations; |
c7b7143c | 141 | if (!(ff->open_flags & FOPEN_KEEP_CACHE)) |
b1009979 | 142 | invalidate_inode_pages2(inode->i_mapping); |
c7b7143c | 143 | if (ff->open_flags & FOPEN_NONSEEKABLE) |
a7c1b990 | 144 | nonseekable_open(inode, file); |
a0822c55 KS |
145 | if (fc->atomic_o_trunc && (file->f_flags & O_TRUNC)) { |
146 | struct fuse_inode *fi = get_fuse_inode(inode); | |
147 | ||
148 | spin_lock(&fc->lock); | |
149 | fi->attr_version = ++fc->attr_version; | |
150 | i_size_write(inode, 0); | |
151 | spin_unlock(&fc->lock); | |
152 | fuse_invalidate_attr(inode); | |
153 | } | |
fd72faac MS |
154 | } |
155 | ||
91fe96b4 | 156 | int fuse_open_common(struct inode *inode, struct file *file, bool isdir) |
fd72faac | 157 | { |
acf99433 | 158 | struct fuse_conn *fc = get_fuse_conn(inode); |
b6aeaded | 159 | int err; |
b6aeaded | 160 | |
dd190d06 MS |
161 | /* VFS checks this, but only _after_ ->open() */ |
162 | if (file->f_flags & O_DIRECT) | |
163 | return -EINVAL; | |
164 | ||
b6aeaded MS |
165 | err = generic_file_open(inode, file); |
166 | if (err) | |
167 | return err; | |
168 | ||
91fe96b4 | 169 | err = fuse_do_open(fc, get_node_id(inode), file, isdir); |
fd72faac | 170 | if (err) |
91fe96b4 | 171 | return err; |
b6aeaded | 172 | |
91fe96b4 MS |
173 | fuse_finish_open(inode, file); |
174 | ||
175 | return 0; | |
b6aeaded MS |
176 | } |
177 | ||
8b0797a4 | 178 | static void fuse_prepare_release(struct fuse_file *ff, int flags, int opcode) |
64c6d8ed | 179 | { |
8b0797a4 | 180 | struct fuse_conn *fc = ff->fc; |
33649c91 | 181 | struct fuse_req *req = ff->reserved_req; |
b57d4264 | 182 | struct fuse_release_in *inarg = &req->misc.release.in; |
b6aeaded | 183 | |
8b0797a4 MS |
184 | spin_lock(&fc->lock); |
185 | list_del(&ff->write_entry); | |
186 | if (!RB_EMPTY_NODE(&ff->polled_node)) | |
187 | rb_erase(&ff->polled_node, &fc->polled_files); | |
188 | spin_unlock(&fc->lock); | |
189 | ||
190 | wake_up_interruptible_sync(&ff->poll_wait); | |
191 | ||
b6aeaded | 192 | inarg->fh = ff->fh; |
fd72faac | 193 | inarg->flags = flags; |
51eb01e7 | 194 | req->in.h.opcode = opcode; |
c7b7143c | 195 | req->in.h.nodeid = ff->nodeid; |
b6aeaded MS |
196 | req->in.numargs = 1; |
197 | req->in.args[0].size = sizeof(struct fuse_release_in); | |
198 | req->in.args[0].value = inarg; | |
fd72faac MS |
199 | } |
200 | ||
8b0797a4 | 201 | void fuse_release_common(struct file *file, int opcode) |
fd72faac | 202 | { |
6b2db28a TH |
203 | struct fuse_file *ff; |
204 | struct fuse_req *req; | |
b6aeaded | 205 | |
6b2db28a TH |
206 | ff = file->private_data; |
207 | if (unlikely(!ff)) | |
8b0797a4 | 208 | return; |
6b2db28a | 209 | |
6b2db28a | 210 | req = ff->reserved_req; |
8b0797a4 | 211 | fuse_prepare_release(ff, file->f_flags, opcode); |
6b2db28a TH |
212 | |
213 | /* Hold vfsmount and dentry until release is finished */ | |
b0be46eb MS |
214 | path_get(&file->f_path); |
215 | req->misc.release.path = file->f_path; | |
6b2db28a | 216 | |
6b2db28a TH |
217 | /* |
218 | * Normally this will send the RELEASE request, however if | |
219 | * some asynchronous READ or WRITE requests are outstanding, | |
220 | * the sending will be delayed. | |
221 | */ | |
222 | fuse_file_put(ff); | |
b6aeaded MS |
223 | } |
224 | ||
04730fef MS |
225 | static int fuse_open(struct inode *inode, struct file *file) |
226 | { | |
91fe96b4 | 227 | return fuse_open_common(inode, file, false); |
04730fef MS |
228 | } |
229 | ||
230 | static int fuse_release(struct inode *inode, struct file *file) | |
231 | { | |
8b0797a4 MS |
232 | fuse_release_common(file, FUSE_RELEASE); |
233 | ||
234 | /* return value is ignored by VFS */ | |
235 | return 0; | |
236 | } | |
237 | ||
238 | void fuse_sync_release(struct fuse_file *ff, int flags) | |
239 | { | |
240 | WARN_ON(atomic_read(&ff->count) > 1); | |
241 | fuse_prepare_release(ff, flags, FUSE_RELEASE); | |
242 | ff->reserved_req->force = 1; | |
243 | fuse_request_send(ff->fc, ff->reserved_req); | |
244 | fuse_put_request(ff->fc, ff->reserved_req); | |
245 | kfree(ff); | |
04730fef | 246 | } |
08cbf542 | 247 | EXPORT_SYMBOL_GPL(fuse_sync_release); |
04730fef | 248 | |
71421259 | 249 | /* |
9c8ef561 MS |
250 | * Scramble the ID space with XTEA, so that the value of the files_struct |
251 | * pointer is not exposed to userspace. | |
71421259 | 252 | */ |
f3332114 | 253 | u64 fuse_lock_owner_id(struct fuse_conn *fc, fl_owner_t id) |
71421259 | 254 | { |
9c8ef561 MS |
255 | u32 *k = fc->scramble_key; |
256 | u64 v = (unsigned long) id; | |
257 | u32 v0 = v; | |
258 | u32 v1 = v >> 32; | |
259 | u32 sum = 0; | |
260 | int i; | |
261 | ||
262 | for (i = 0; i < 32; i++) { | |
263 | v0 += ((v1 << 4 ^ v1 >> 5) + v1) ^ (sum + k[sum & 3]); | |
264 | sum += 0x9E3779B9; | |
265 | v1 += ((v0 << 4 ^ v0 >> 5) + v0) ^ (sum + k[sum>>11 & 3]); | |
266 | } | |
267 | ||
268 | return (u64) v0 + ((u64) v1 << 32); | |
71421259 MS |
269 | } |
270 | ||
3be5a52b MS |
271 | /* |
272 | * Check if page is under writeback | |
273 | * | |
274 | * This is currently done by walking the list of writepage requests | |
275 | * for the inode, which can be pretty inefficient. | |
276 | */ | |
277 | static bool fuse_page_is_writeback(struct inode *inode, pgoff_t index) | |
278 | { | |
279 | struct fuse_conn *fc = get_fuse_conn(inode); | |
280 | struct fuse_inode *fi = get_fuse_inode(inode); | |
281 | struct fuse_req *req; | |
282 | bool found = false; | |
283 | ||
284 | spin_lock(&fc->lock); | |
285 | list_for_each_entry(req, &fi->writepages, writepages_entry) { | |
286 | pgoff_t curr_index; | |
287 | ||
288 | BUG_ON(req->inode != inode); | |
289 | curr_index = req->misc.write.in.offset >> PAGE_CACHE_SHIFT; | |
290 | if (curr_index == index) { | |
291 | found = true; | |
292 | break; | |
293 | } | |
294 | } | |
295 | spin_unlock(&fc->lock); | |
296 | ||
297 | return found; | |
298 | } | |
299 | ||
300 | /* | |
301 | * Wait for page writeback to be completed. | |
302 | * | |
303 | * Since fuse doesn't rely on the VM writeback tracking, this has to | |
304 | * use some other means. | |
305 | */ | |
306 | static int fuse_wait_on_page_writeback(struct inode *inode, pgoff_t index) | |
307 | { | |
308 | struct fuse_inode *fi = get_fuse_inode(inode); | |
309 | ||
310 | wait_event(fi->page_waitq, !fuse_page_is_writeback(inode, index)); | |
311 | return 0; | |
312 | } | |
313 | ||
75e1fcc0 | 314 | static int fuse_flush(struct file *file, fl_owner_t id) |
b6aeaded | 315 | { |
7706a9d6 | 316 | struct inode *inode = file->f_path.dentry->d_inode; |
b6aeaded MS |
317 | struct fuse_conn *fc = get_fuse_conn(inode); |
318 | struct fuse_file *ff = file->private_data; | |
319 | struct fuse_req *req; | |
320 | struct fuse_flush_in inarg; | |
321 | int err; | |
322 | ||
248d86e8 MS |
323 | if (is_bad_inode(inode)) |
324 | return -EIO; | |
325 | ||
b6aeaded MS |
326 | if (fc->no_flush) |
327 | return 0; | |
328 | ||
33649c91 | 329 | req = fuse_get_req_nofail(fc, file); |
b6aeaded MS |
330 | memset(&inarg, 0, sizeof(inarg)); |
331 | inarg.fh = ff->fh; | |
9c8ef561 | 332 | inarg.lock_owner = fuse_lock_owner_id(fc, id); |
b6aeaded MS |
333 | req->in.h.opcode = FUSE_FLUSH; |
334 | req->in.h.nodeid = get_node_id(inode); | |
b6aeaded MS |
335 | req->in.numargs = 1; |
336 | req->in.args[0].size = sizeof(inarg); | |
337 | req->in.args[0].value = &inarg; | |
71421259 | 338 | req->force = 1; |
b93f858a | 339 | fuse_request_send(fc, req); |
b6aeaded MS |
340 | err = req->out.h.error; |
341 | fuse_put_request(fc, req); | |
342 | if (err == -ENOSYS) { | |
343 | fc->no_flush = 1; | |
344 | err = 0; | |
345 | } | |
346 | return err; | |
347 | } | |
348 | ||
3be5a52b MS |
349 | /* |
350 | * Wait for all pending writepages on the inode to finish. | |
351 | * | |
352 | * This is currently done by blocking further writes with FUSE_NOWRITE | |
353 | * and waiting for all sent writes to complete. | |
354 | * | |
355 | * This must be called under i_mutex, otherwise the FUSE_NOWRITE usage | |
356 | * could conflict with truncation. | |
357 | */ | |
358 | static void fuse_sync_writes(struct inode *inode) | |
359 | { | |
360 | fuse_set_nowrite(inode); | |
361 | fuse_release_nowrite(inode); | |
362 | } | |
363 | ||
7ea80859 | 364 | int fuse_fsync_common(struct file *file, int datasync, int isdir) |
b6aeaded | 365 | { |
7ea80859 | 366 | struct inode *inode = file->f_mapping->host; |
b6aeaded MS |
367 | struct fuse_conn *fc = get_fuse_conn(inode); |
368 | struct fuse_file *ff = file->private_data; | |
369 | struct fuse_req *req; | |
370 | struct fuse_fsync_in inarg; | |
371 | int err; | |
372 | ||
248d86e8 MS |
373 | if (is_bad_inode(inode)) |
374 | return -EIO; | |
375 | ||
82547981 | 376 | if ((!isdir && fc->no_fsync) || (isdir && fc->no_fsyncdir)) |
b6aeaded MS |
377 | return 0; |
378 | ||
3be5a52b MS |
379 | /* |
380 | * Start writeback against all dirty pages of the inode, then | |
381 | * wait for all outstanding writes, before sending the FSYNC | |
382 | * request. | |
383 | */ | |
384 | err = write_inode_now(inode, 0); | |
385 | if (err) | |
386 | return err; | |
387 | ||
388 | fuse_sync_writes(inode); | |
389 | ||
ce1d5a49 MS |
390 | req = fuse_get_req(fc); |
391 | if (IS_ERR(req)) | |
392 | return PTR_ERR(req); | |
b6aeaded MS |
393 | |
394 | memset(&inarg, 0, sizeof(inarg)); | |
395 | inarg.fh = ff->fh; | |
396 | inarg.fsync_flags = datasync ? 1 : 0; | |
82547981 | 397 | req->in.h.opcode = isdir ? FUSE_FSYNCDIR : FUSE_FSYNC; |
b6aeaded | 398 | req->in.h.nodeid = get_node_id(inode); |
b6aeaded MS |
399 | req->in.numargs = 1; |
400 | req->in.args[0].size = sizeof(inarg); | |
401 | req->in.args[0].value = &inarg; | |
b93f858a | 402 | fuse_request_send(fc, req); |
b6aeaded MS |
403 | err = req->out.h.error; |
404 | fuse_put_request(fc, req); | |
405 | if (err == -ENOSYS) { | |
82547981 MS |
406 | if (isdir) |
407 | fc->no_fsyncdir = 1; | |
408 | else | |
409 | fc->no_fsync = 1; | |
b6aeaded MS |
410 | err = 0; |
411 | } | |
412 | return err; | |
413 | } | |
414 | ||
7ea80859 | 415 | static int fuse_fsync(struct file *file, int datasync) |
82547981 | 416 | { |
7ea80859 | 417 | return fuse_fsync_common(file, datasync, 0); |
82547981 MS |
418 | } |
419 | ||
2106cb18 MS |
420 | void fuse_read_fill(struct fuse_req *req, struct file *file, loff_t pos, |
421 | size_t count, int opcode) | |
b6aeaded | 422 | { |
5c5c5e51 | 423 | struct fuse_read_in *inarg = &req->misc.read.in; |
a6643094 | 424 | struct fuse_file *ff = file->private_data; |
b6aeaded | 425 | |
361b1eb5 MS |
426 | inarg->fh = ff->fh; |
427 | inarg->offset = pos; | |
428 | inarg->size = count; | |
a6643094 | 429 | inarg->flags = file->f_flags; |
361b1eb5 | 430 | req->in.h.opcode = opcode; |
2106cb18 | 431 | req->in.h.nodeid = ff->nodeid; |
b6aeaded MS |
432 | req->in.numargs = 1; |
433 | req->in.args[0].size = sizeof(struct fuse_read_in); | |
c1aa96a5 | 434 | req->in.args[0].value = inarg; |
b6aeaded MS |
435 | req->out.argvar = 1; |
436 | req->out.numargs = 1; | |
437 | req->out.args[0].size = count; | |
b6aeaded MS |
438 | } |
439 | ||
8bfc016d | 440 | static size_t fuse_send_read(struct fuse_req *req, struct file *file, |
2106cb18 | 441 | loff_t pos, size_t count, fl_owner_t owner) |
04730fef | 442 | { |
2106cb18 MS |
443 | struct fuse_file *ff = file->private_data; |
444 | struct fuse_conn *fc = ff->fc; | |
f3332114 | 445 | |
2106cb18 | 446 | fuse_read_fill(req, file, pos, count, FUSE_READ); |
f3332114 | 447 | if (owner != NULL) { |
5c5c5e51 | 448 | struct fuse_read_in *inarg = &req->misc.read.in; |
f3332114 MS |
449 | |
450 | inarg->read_flags |= FUSE_READ_LOCKOWNER; | |
451 | inarg->lock_owner = fuse_lock_owner_id(fc, owner); | |
452 | } | |
b93f858a | 453 | fuse_request_send(fc, req); |
361b1eb5 | 454 | return req->out.args[0].size; |
04730fef MS |
455 | } |
456 | ||
5c5c5e51 MS |
457 | static void fuse_read_update_size(struct inode *inode, loff_t size, |
458 | u64 attr_ver) | |
459 | { | |
460 | struct fuse_conn *fc = get_fuse_conn(inode); | |
461 | struct fuse_inode *fi = get_fuse_inode(inode); | |
462 | ||
463 | spin_lock(&fc->lock); | |
464 | if (attr_ver == fi->attr_version && size < inode->i_size) { | |
465 | fi->attr_version = ++fc->attr_version; | |
466 | i_size_write(inode, size); | |
467 | } | |
468 | spin_unlock(&fc->lock); | |
469 | } | |
470 | ||
b6aeaded MS |
471 | static int fuse_readpage(struct file *file, struct page *page) |
472 | { | |
473 | struct inode *inode = page->mapping->host; | |
474 | struct fuse_conn *fc = get_fuse_conn(inode); | |
248d86e8 | 475 | struct fuse_req *req; |
5c5c5e51 MS |
476 | size_t num_read; |
477 | loff_t pos = page_offset(page); | |
478 | size_t count = PAGE_CACHE_SIZE; | |
479 | u64 attr_ver; | |
248d86e8 MS |
480 | int err; |
481 | ||
482 | err = -EIO; | |
483 | if (is_bad_inode(inode)) | |
484 | goto out; | |
485 | ||
3be5a52b MS |
486 | /* |
487 | * Page writeback can extend beyond the liftime of the | |
488 | * page-cache page, so make sure we read a properly synced | |
489 | * page. | |
490 | */ | |
491 | fuse_wait_on_page_writeback(inode, page->index); | |
492 | ||
ce1d5a49 MS |
493 | req = fuse_get_req(fc); |
494 | err = PTR_ERR(req); | |
495 | if (IS_ERR(req)) | |
b6aeaded MS |
496 | goto out; |
497 | ||
5c5c5e51 MS |
498 | attr_ver = fuse_get_attr_version(fc); |
499 | ||
b6aeaded | 500 | req->out.page_zeroing = 1; |
f4975c67 | 501 | req->out.argpages = 1; |
b6aeaded MS |
502 | req->num_pages = 1; |
503 | req->pages[0] = page; | |
2106cb18 | 504 | num_read = fuse_send_read(req, file, pos, count, NULL); |
b6aeaded MS |
505 | err = req->out.h.error; |
506 | fuse_put_request(fc, req); | |
5c5c5e51 MS |
507 | |
508 | if (!err) { | |
509 | /* | |
510 | * Short read means EOF. If file size is larger, truncate it | |
511 | */ | |
512 | if (num_read < count) | |
513 | fuse_read_update_size(inode, pos + num_read, attr_ver); | |
514 | ||
b6aeaded | 515 | SetPageUptodate(page); |
5c5c5e51 MS |
516 | } |
517 | ||
b36c31ba | 518 | fuse_invalidate_attr(inode); /* atime changed */ |
b6aeaded MS |
519 | out: |
520 | unlock_page(page); | |
521 | return err; | |
522 | } | |
523 | ||
c1aa96a5 | 524 | static void fuse_readpages_end(struct fuse_conn *fc, struct fuse_req *req) |
db50b96c | 525 | { |
c1aa96a5 | 526 | int i; |
5c5c5e51 MS |
527 | size_t count = req->misc.read.in.size; |
528 | size_t num_read = req->out.args[0].size; | |
ce534fb0 | 529 | struct address_space *mapping = NULL; |
c1aa96a5 | 530 | |
ce534fb0 MS |
531 | for (i = 0; mapping == NULL && i < req->num_pages; i++) |
532 | mapping = req->pages[i]->mapping; | |
5c5c5e51 | 533 | |
ce534fb0 MS |
534 | if (mapping) { |
535 | struct inode *inode = mapping->host; | |
536 | ||
537 | /* | |
538 | * Short read means EOF. If file size is larger, truncate it | |
539 | */ | |
540 | if (!req->out.h.error && num_read < count) { | |
541 | loff_t pos; | |
542 | ||
543 | pos = page_offset(req->pages[0]) + num_read; | |
544 | fuse_read_update_size(inode, pos, | |
545 | req->misc.read.attr_ver); | |
546 | } | |
547 | fuse_invalidate_attr(inode); /* atime changed */ | |
548 | } | |
c1aa96a5 | 549 | |
db50b96c MS |
550 | for (i = 0; i < req->num_pages; i++) { |
551 | struct page *page = req->pages[i]; | |
552 | if (!req->out.h.error) | |
553 | SetPageUptodate(page); | |
c1aa96a5 MS |
554 | else |
555 | SetPageError(page); | |
db50b96c | 556 | unlock_page(page); |
b5dd3285 | 557 | page_cache_release(page); |
db50b96c | 558 | } |
c756e0a4 MS |
559 | if (req->ff) |
560 | fuse_file_put(req->ff); | |
c1aa96a5 MS |
561 | } |
562 | ||
2106cb18 | 563 | static void fuse_send_readpages(struct fuse_req *req, struct file *file) |
c1aa96a5 | 564 | { |
2106cb18 MS |
565 | struct fuse_file *ff = file->private_data; |
566 | struct fuse_conn *fc = ff->fc; | |
c1aa96a5 MS |
567 | loff_t pos = page_offset(req->pages[0]); |
568 | size_t count = req->num_pages << PAGE_CACHE_SHIFT; | |
f4975c67 MS |
569 | |
570 | req->out.argpages = 1; | |
c1aa96a5 | 571 | req->out.page_zeroing = 1; |
ce534fb0 | 572 | req->out.page_replace = 1; |
2106cb18 | 573 | fuse_read_fill(req, file, pos, count, FUSE_READ); |
5c5c5e51 | 574 | req->misc.read.attr_ver = fuse_get_attr_version(fc); |
9cd68455 | 575 | if (fc->async_read) { |
c756e0a4 | 576 | req->ff = fuse_file_get(ff); |
9cd68455 | 577 | req->end = fuse_readpages_end; |
b93f858a | 578 | fuse_request_send_background(fc, req); |
9cd68455 | 579 | } else { |
b93f858a | 580 | fuse_request_send(fc, req); |
9cd68455 | 581 | fuse_readpages_end(fc, req); |
e9bb09dd | 582 | fuse_put_request(fc, req); |
9cd68455 | 583 | } |
db50b96c MS |
584 | } |
585 | ||
c756e0a4 | 586 | struct fuse_fill_data { |
db50b96c | 587 | struct fuse_req *req; |
a6643094 | 588 | struct file *file; |
db50b96c MS |
589 | struct inode *inode; |
590 | }; | |
591 | ||
592 | static int fuse_readpages_fill(void *_data, struct page *page) | |
593 | { | |
c756e0a4 | 594 | struct fuse_fill_data *data = _data; |
db50b96c MS |
595 | struct fuse_req *req = data->req; |
596 | struct inode *inode = data->inode; | |
597 | struct fuse_conn *fc = get_fuse_conn(inode); | |
598 | ||
3be5a52b MS |
599 | fuse_wait_on_page_writeback(inode, page->index); |
600 | ||
db50b96c MS |
601 | if (req->num_pages && |
602 | (req->num_pages == FUSE_MAX_PAGES_PER_REQ || | |
603 | (req->num_pages + 1) * PAGE_CACHE_SIZE > fc->max_read || | |
604 | req->pages[req->num_pages - 1]->index + 1 != page->index)) { | |
2106cb18 | 605 | fuse_send_readpages(req, data->file); |
ce1d5a49 MS |
606 | data->req = req = fuse_get_req(fc); |
607 | if (IS_ERR(req)) { | |
db50b96c | 608 | unlock_page(page); |
ce1d5a49 | 609 | return PTR_ERR(req); |
db50b96c | 610 | } |
db50b96c | 611 | } |
b5dd3285 | 612 | page_cache_get(page); |
db50b96c | 613 | req->pages[req->num_pages] = page; |
1729a16c | 614 | req->num_pages++; |
db50b96c MS |
615 | return 0; |
616 | } | |
617 | ||
618 | static int fuse_readpages(struct file *file, struct address_space *mapping, | |
619 | struct list_head *pages, unsigned nr_pages) | |
620 | { | |
621 | struct inode *inode = mapping->host; | |
622 | struct fuse_conn *fc = get_fuse_conn(inode); | |
c756e0a4 | 623 | struct fuse_fill_data data; |
db50b96c | 624 | int err; |
248d86e8 | 625 | |
1d7ea732 | 626 | err = -EIO; |
248d86e8 | 627 | if (is_bad_inode(inode)) |
2e990021 | 628 | goto out; |
248d86e8 | 629 | |
a6643094 | 630 | data.file = file; |
db50b96c | 631 | data.inode = inode; |
ce1d5a49 | 632 | data.req = fuse_get_req(fc); |
1d7ea732 | 633 | err = PTR_ERR(data.req); |
ce1d5a49 | 634 | if (IS_ERR(data.req)) |
2e990021 | 635 | goto out; |
db50b96c MS |
636 | |
637 | err = read_cache_pages(mapping, pages, fuse_readpages_fill, &data); | |
d3406ffa MS |
638 | if (!err) { |
639 | if (data.req->num_pages) | |
2106cb18 | 640 | fuse_send_readpages(data.req, file); |
d3406ffa MS |
641 | else |
642 | fuse_put_request(fc, data.req); | |
643 | } | |
2e990021 | 644 | out: |
1d7ea732 | 645 | return err; |
db50b96c MS |
646 | } |
647 | ||
bcb4be80 MS |
648 | static ssize_t fuse_file_aio_read(struct kiocb *iocb, const struct iovec *iov, |
649 | unsigned long nr_segs, loff_t pos) | |
650 | { | |
651 | struct inode *inode = iocb->ki_filp->f_mapping->host; | |
652 | ||
653 | if (pos + iov_length(iov, nr_segs) > i_size_read(inode)) { | |
654 | int err; | |
655 | /* | |
656 | * If trying to read past EOF, make sure the i_size | |
657 | * attribute is up-to-date. | |
658 | */ | |
659 | err = fuse_update_attributes(inode, NULL, iocb->ki_filp, NULL); | |
660 | if (err) | |
661 | return err; | |
662 | } | |
663 | ||
664 | return generic_file_aio_read(iocb, iov, nr_segs, pos); | |
665 | } | |
666 | ||
2d698b07 | 667 | static void fuse_write_fill(struct fuse_req *req, struct fuse_file *ff, |
2106cb18 | 668 | loff_t pos, size_t count) |
b6aeaded | 669 | { |
b25e82e5 MS |
670 | struct fuse_write_in *inarg = &req->misc.write.in; |
671 | struct fuse_write_out *outarg = &req->misc.write.out; | |
b6aeaded | 672 | |
b25e82e5 MS |
673 | inarg->fh = ff->fh; |
674 | inarg->offset = pos; | |
675 | inarg->size = count; | |
b6aeaded | 676 | req->in.h.opcode = FUSE_WRITE; |
2106cb18 | 677 | req->in.h.nodeid = ff->nodeid; |
b6aeaded | 678 | req->in.numargs = 2; |
2106cb18 | 679 | if (ff->fc->minor < 9) |
f3332114 MS |
680 | req->in.args[0].size = FUSE_COMPAT_WRITE_IN_SIZE; |
681 | else | |
682 | req->in.args[0].size = sizeof(struct fuse_write_in); | |
b25e82e5 | 683 | req->in.args[0].value = inarg; |
b6aeaded MS |
684 | req->in.args[1].size = count; |
685 | req->out.numargs = 1; | |
686 | req->out.args[0].size = sizeof(struct fuse_write_out); | |
b25e82e5 MS |
687 | req->out.args[0].value = outarg; |
688 | } | |
689 | ||
690 | static size_t fuse_send_write(struct fuse_req *req, struct file *file, | |
2106cb18 | 691 | loff_t pos, size_t count, fl_owner_t owner) |
b25e82e5 | 692 | { |
2106cb18 MS |
693 | struct fuse_file *ff = file->private_data; |
694 | struct fuse_conn *fc = ff->fc; | |
2d698b07 MS |
695 | struct fuse_write_in *inarg = &req->misc.write.in; |
696 | ||
2106cb18 | 697 | fuse_write_fill(req, ff, pos, count); |
2d698b07 | 698 | inarg->flags = file->f_flags; |
f3332114 | 699 | if (owner != NULL) { |
f3332114 MS |
700 | inarg->write_flags |= FUSE_WRITE_LOCKOWNER; |
701 | inarg->lock_owner = fuse_lock_owner_id(fc, owner); | |
702 | } | |
b93f858a | 703 | fuse_request_send(fc, req); |
b25e82e5 | 704 | return req->misc.write.out.size; |
b6aeaded MS |
705 | } |
706 | ||
5e6f58a1 NP |
707 | static int fuse_write_begin(struct file *file, struct address_space *mapping, |
708 | loff_t pos, unsigned len, unsigned flags, | |
709 | struct page **pagep, void **fsdata) | |
b6aeaded | 710 | { |
5e6f58a1 NP |
711 | pgoff_t index = pos >> PAGE_CACHE_SHIFT; |
712 | ||
54566b2c | 713 | *pagep = grab_cache_page_write_begin(mapping, index, flags); |
5e6f58a1 NP |
714 | if (!*pagep) |
715 | return -ENOMEM; | |
b6aeaded MS |
716 | return 0; |
717 | } | |
718 | ||
a1d75f25 | 719 | void fuse_write_update_size(struct inode *inode, loff_t pos) |
854512ec MS |
720 | { |
721 | struct fuse_conn *fc = get_fuse_conn(inode); | |
722 | struct fuse_inode *fi = get_fuse_inode(inode); | |
723 | ||
724 | spin_lock(&fc->lock); | |
725 | fi->attr_version = ++fc->attr_version; | |
726 | if (pos > inode->i_size) | |
727 | i_size_write(inode, pos); | |
728 | spin_unlock(&fc->lock); | |
729 | } | |
730 | ||
5e6f58a1 NP |
731 | static int fuse_buffered_write(struct file *file, struct inode *inode, |
732 | loff_t pos, unsigned count, struct page *page) | |
b6aeaded MS |
733 | { |
734 | int err; | |
04730fef | 735 | size_t nres; |
b6aeaded | 736 | struct fuse_conn *fc = get_fuse_conn(inode); |
5e6f58a1 | 737 | unsigned offset = pos & (PAGE_CACHE_SIZE - 1); |
248d86e8 MS |
738 | struct fuse_req *req; |
739 | ||
740 | if (is_bad_inode(inode)) | |
741 | return -EIO; | |
742 | ||
3be5a52b MS |
743 | /* |
744 | * Make sure writepages on the same page are not mixed up with | |
745 | * plain writes. | |
746 | */ | |
747 | fuse_wait_on_page_writeback(inode, page->index); | |
748 | ||
ce1d5a49 MS |
749 | req = fuse_get_req(fc); |
750 | if (IS_ERR(req)) | |
751 | return PTR_ERR(req); | |
b6aeaded | 752 | |
f4975c67 | 753 | req->in.argpages = 1; |
b6aeaded MS |
754 | req->num_pages = 1; |
755 | req->pages[0] = page; | |
756 | req->page_offset = offset; | |
2106cb18 | 757 | nres = fuse_send_write(req, file, pos, count, NULL); |
b6aeaded MS |
758 | err = req->out.h.error; |
759 | fuse_put_request(fc, req); | |
5e6f58a1 | 760 | if (!err && !nres) |
b6aeaded MS |
761 | err = -EIO; |
762 | if (!err) { | |
5e6f58a1 | 763 | pos += nres; |
854512ec | 764 | fuse_write_update_size(inode, pos); |
5e6f58a1 | 765 | if (count == PAGE_CACHE_SIZE) |
b6aeaded | 766 | SetPageUptodate(page); |
b36c31ba MS |
767 | } |
768 | fuse_invalidate_attr(inode); | |
5e6f58a1 NP |
769 | return err ? err : nres; |
770 | } | |
771 | ||
772 | static int fuse_write_end(struct file *file, struct address_space *mapping, | |
773 | loff_t pos, unsigned len, unsigned copied, | |
774 | struct page *page, void *fsdata) | |
775 | { | |
776 | struct inode *inode = mapping->host; | |
777 | int res = 0; | |
778 | ||
779 | if (copied) | |
780 | res = fuse_buffered_write(file, inode, pos, copied, page); | |
781 | ||
782 | unlock_page(page); | |
783 | page_cache_release(page); | |
784 | return res; | |
b6aeaded MS |
785 | } |
786 | ||
ea9b9907 NP |
787 | static size_t fuse_send_write_pages(struct fuse_req *req, struct file *file, |
788 | struct inode *inode, loff_t pos, | |
789 | size_t count) | |
790 | { | |
791 | size_t res; | |
792 | unsigned offset; | |
793 | unsigned i; | |
794 | ||
795 | for (i = 0; i < req->num_pages; i++) | |
796 | fuse_wait_on_page_writeback(inode, req->pages[i]->index); | |
797 | ||
2106cb18 | 798 | res = fuse_send_write(req, file, pos, count, NULL); |
ea9b9907 NP |
799 | |
800 | offset = req->page_offset; | |
801 | count = res; | |
802 | for (i = 0; i < req->num_pages; i++) { | |
803 | struct page *page = req->pages[i]; | |
804 | ||
805 | if (!req->out.h.error && !offset && count >= PAGE_CACHE_SIZE) | |
806 | SetPageUptodate(page); | |
807 | ||
808 | if (count > PAGE_CACHE_SIZE - offset) | |
809 | count -= PAGE_CACHE_SIZE - offset; | |
810 | else | |
811 | count = 0; | |
812 | offset = 0; | |
813 | ||
814 | unlock_page(page); | |
815 | page_cache_release(page); | |
816 | } | |
817 | ||
818 | return res; | |
819 | } | |
820 | ||
821 | static ssize_t fuse_fill_write_pages(struct fuse_req *req, | |
822 | struct address_space *mapping, | |
823 | struct iov_iter *ii, loff_t pos) | |
824 | { | |
825 | struct fuse_conn *fc = get_fuse_conn(mapping->host); | |
826 | unsigned offset = pos & (PAGE_CACHE_SIZE - 1); | |
827 | size_t count = 0; | |
828 | int err; | |
829 | ||
f4975c67 | 830 | req->in.argpages = 1; |
ea9b9907 NP |
831 | req->page_offset = offset; |
832 | ||
833 | do { | |
834 | size_t tmp; | |
835 | struct page *page; | |
836 | pgoff_t index = pos >> PAGE_CACHE_SHIFT; | |
837 | size_t bytes = min_t(size_t, PAGE_CACHE_SIZE - offset, | |
838 | iov_iter_count(ii)); | |
839 | ||
840 | bytes = min_t(size_t, bytes, fc->max_write - count); | |
841 | ||
842 | again: | |
843 | err = -EFAULT; | |
844 | if (iov_iter_fault_in_readable(ii, bytes)) | |
845 | break; | |
846 | ||
847 | err = -ENOMEM; | |
54566b2c | 848 | page = grab_cache_page_write_begin(mapping, index, 0); |
ea9b9907 NP |
849 | if (!page) |
850 | break; | |
851 | ||
931e80e4 | 852 | if (mapping_writably_mapped(mapping)) |
853 | flush_dcache_page(page); | |
854 | ||
ea9b9907 NP |
855 | pagefault_disable(); |
856 | tmp = iov_iter_copy_from_user_atomic(page, ii, offset, bytes); | |
857 | pagefault_enable(); | |
858 | flush_dcache_page(page); | |
859 | ||
860 | if (!tmp) { | |
861 | unlock_page(page); | |
862 | page_cache_release(page); | |
863 | bytes = min(bytes, iov_iter_single_seg_count(ii)); | |
864 | goto again; | |
865 | } | |
866 | ||
867 | err = 0; | |
868 | req->pages[req->num_pages] = page; | |
869 | req->num_pages++; | |
870 | ||
871 | iov_iter_advance(ii, tmp); | |
872 | count += tmp; | |
873 | pos += tmp; | |
874 | offset += tmp; | |
875 | if (offset == PAGE_CACHE_SIZE) | |
876 | offset = 0; | |
877 | ||
78bb6cb9 MS |
878 | if (!fc->big_writes) |
879 | break; | |
ea9b9907 NP |
880 | } while (iov_iter_count(ii) && count < fc->max_write && |
881 | req->num_pages < FUSE_MAX_PAGES_PER_REQ && offset == 0); | |
882 | ||
883 | return count > 0 ? count : err; | |
884 | } | |
885 | ||
886 | static ssize_t fuse_perform_write(struct file *file, | |
887 | struct address_space *mapping, | |
888 | struct iov_iter *ii, loff_t pos) | |
889 | { | |
890 | struct inode *inode = mapping->host; | |
891 | struct fuse_conn *fc = get_fuse_conn(inode); | |
892 | int err = 0; | |
893 | ssize_t res = 0; | |
894 | ||
895 | if (is_bad_inode(inode)) | |
896 | return -EIO; | |
897 | ||
898 | do { | |
899 | struct fuse_req *req; | |
900 | ssize_t count; | |
901 | ||
902 | req = fuse_get_req(fc); | |
903 | if (IS_ERR(req)) { | |
904 | err = PTR_ERR(req); | |
905 | break; | |
906 | } | |
907 | ||
908 | count = fuse_fill_write_pages(req, mapping, ii, pos); | |
909 | if (count <= 0) { | |
910 | err = count; | |
911 | } else { | |
912 | size_t num_written; | |
913 | ||
914 | num_written = fuse_send_write_pages(req, file, inode, | |
915 | pos, count); | |
916 | err = req->out.h.error; | |
917 | if (!err) { | |
918 | res += num_written; | |
919 | pos += num_written; | |
920 | ||
921 | /* break out of the loop on short write */ | |
922 | if (num_written != count) | |
923 | err = -EIO; | |
924 | } | |
925 | } | |
926 | fuse_put_request(fc, req); | |
927 | } while (!err && iov_iter_count(ii)); | |
928 | ||
929 | if (res > 0) | |
930 | fuse_write_update_size(inode, pos); | |
931 | ||
932 | fuse_invalidate_attr(inode); | |
933 | ||
934 | return res > 0 ? res : err; | |
935 | } | |
936 | ||
937 | static ssize_t fuse_file_aio_write(struct kiocb *iocb, const struct iovec *iov, | |
938 | unsigned long nr_segs, loff_t pos) | |
939 | { | |
940 | struct file *file = iocb->ki_filp; | |
941 | struct address_space *mapping = file->f_mapping; | |
942 | size_t count = 0; | |
943 | ssize_t written = 0; | |
944 | struct inode *inode = mapping->host; | |
945 | ssize_t err; | |
946 | struct iov_iter i; | |
947 | ||
948 | WARN_ON(iocb->ki_pos != pos); | |
949 | ||
950 | err = generic_segment_checks(iov, &nr_segs, &count, VERIFY_READ); | |
951 | if (err) | |
952 | return err; | |
953 | ||
954 | mutex_lock(&inode->i_mutex); | |
955 | vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE); | |
956 | ||
957 | /* We can write back this queue in page reclaim */ | |
958 | current->backing_dev_info = mapping->backing_dev_info; | |
959 | ||
960 | err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode)); | |
961 | if (err) | |
962 | goto out; | |
963 | ||
964 | if (count == 0) | |
965 | goto out; | |
966 | ||
2f1936b8 | 967 | err = file_remove_suid(file); |
ea9b9907 NP |
968 | if (err) |
969 | goto out; | |
970 | ||
971 | file_update_time(file); | |
972 | ||
973 | iov_iter_init(&i, iov, nr_segs, count, 0); | |
974 | written = fuse_perform_write(file, mapping, &i, pos); | |
975 | if (written >= 0) | |
976 | iocb->ki_pos = pos + written; | |
977 | ||
978 | out: | |
979 | current->backing_dev_info = NULL; | |
980 | mutex_unlock(&inode->i_mutex); | |
981 | ||
982 | return written ? written : err; | |
983 | } | |
984 | ||
413ef8cb MS |
985 | static void fuse_release_user_pages(struct fuse_req *req, int write) |
986 | { | |
987 | unsigned i; | |
988 | ||
989 | for (i = 0; i < req->num_pages; i++) { | |
990 | struct page *page = req->pages[i]; | |
991 | if (write) | |
992 | set_page_dirty_lock(page); | |
993 | put_page(page); | |
994 | } | |
995 | } | |
996 | ||
997 | static int fuse_get_user_pages(struct fuse_req *req, const char __user *buf, | |
ce60a2f1 | 998 | size_t *nbytesp, int write) |
413ef8cb | 999 | { |
ce60a2f1 | 1000 | size_t nbytes = *nbytesp; |
413ef8cb MS |
1001 | unsigned long user_addr = (unsigned long) buf; |
1002 | unsigned offset = user_addr & ~PAGE_MASK; | |
1003 | int npages; | |
1004 | ||
f4975c67 MS |
1005 | /* Special case for kernel I/O: can copy directly into the buffer */ |
1006 | if (segment_eq(get_fs(), KERNEL_DS)) { | |
1007 | if (write) | |
1008 | req->in.args[1].value = (void *) user_addr; | |
1009 | else | |
1010 | req->out.args[0].value = (void *) user_addr; | |
1011 | ||
1012 | return 0; | |
1013 | } | |
413ef8cb | 1014 | |
ce60a2f1 | 1015 | nbytes = min_t(size_t, nbytes, FUSE_MAX_PAGES_PER_REQ << PAGE_SHIFT); |
413ef8cb | 1016 | npages = (nbytes + offset + PAGE_SIZE - 1) >> PAGE_SHIFT; |
bd730967 | 1017 | npages = clamp(npages, 1, FUSE_MAX_PAGES_PER_REQ); |
1bf94ca7 | 1018 | npages = get_user_pages_fast(user_addr, npages, !write, req->pages); |
413ef8cb MS |
1019 | if (npages < 0) |
1020 | return npages; | |
1021 | ||
1022 | req->num_pages = npages; | |
1023 | req->page_offset = offset; | |
f4975c67 MS |
1024 | |
1025 | if (write) | |
1026 | req->in.argpages = 1; | |
1027 | else | |
1028 | req->out.argpages = 1; | |
1029 | ||
1030 | nbytes = (req->num_pages << PAGE_SHIFT) - req->page_offset; | |
1031 | *nbytesp = min(*nbytesp, nbytes); | |
1032 | ||
413ef8cb MS |
1033 | return 0; |
1034 | } | |
1035 | ||
08cbf542 TH |
1036 | ssize_t fuse_direct_io(struct file *file, const char __user *buf, |
1037 | size_t count, loff_t *ppos, int write) | |
413ef8cb | 1038 | { |
2106cb18 MS |
1039 | struct fuse_file *ff = file->private_data; |
1040 | struct fuse_conn *fc = ff->fc; | |
413ef8cb MS |
1041 | size_t nmax = write ? fc->max_write : fc->max_read; |
1042 | loff_t pos = *ppos; | |
1043 | ssize_t res = 0; | |
248d86e8 MS |
1044 | struct fuse_req *req; |
1045 | ||
ce1d5a49 MS |
1046 | req = fuse_get_req(fc); |
1047 | if (IS_ERR(req)) | |
1048 | return PTR_ERR(req); | |
413ef8cb MS |
1049 | |
1050 | while (count) { | |
413ef8cb | 1051 | size_t nres; |
2106cb18 | 1052 | fl_owner_t owner = current->files; |
f4975c67 MS |
1053 | size_t nbytes = min(count, nmax); |
1054 | int err = fuse_get_user_pages(req, buf, &nbytes, write); | |
413ef8cb MS |
1055 | if (err) { |
1056 | res = err; | |
1057 | break; | |
1058 | } | |
f4975c67 | 1059 | |
413ef8cb | 1060 | if (write) |
2106cb18 | 1061 | nres = fuse_send_write(req, file, pos, nbytes, owner); |
413ef8cb | 1062 | else |
2106cb18 MS |
1063 | nres = fuse_send_read(req, file, pos, nbytes, owner); |
1064 | ||
413ef8cb MS |
1065 | fuse_release_user_pages(req, !write); |
1066 | if (req->out.h.error) { | |
1067 | if (!res) | |
1068 | res = req->out.h.error; | |
1069 | break; | |
1070 | } else if (nres > nbytes) { | |
1071 | res = -EIO; | |
1072 | break; | |
1073 | } | |
1074 | count -= nres; | |
1075 | res += nres; | |
1076 | pos += nres; | |
1077 | buf += nres; | |
1078 | if (nres != nbytes) | |
1079 | break; | |
56cf34ff MS |
1080 | if (count) { |
1081 | fuse_put_request(fc, req); | |
1082 | req = fuse_get_req(fc); | |
1083 | if (IS_ERR(req)) | |
1084 | break; | |
1085 | } | |
413ef8cb | 1086 | } |
f60311d5 AA |
1087 | if (!IS_ERR(req)) |
1088 | fuse_put_request(fc, req); | |
d09cb9d7 | 1089 | if (res > 0) |
413ef8cb | 1090 | *ppos = pos; |
413ef8cb MS |
1091 | |
1092 | return res; | |
1093 | } | |
08cbf542 | 1094 | EXPORT_SYMBOL_GPL(fuse_direct_io); |
413ef8cb MS |
1095 | |
1096 | static ssize_t fuse_direct_read(struct file *file, char __user *buf, | |
1097 | size_t count, loff_t *ppos) | |
1098 | { | |
d09cb9d7 MS |
1099 | ssize_t res; |
1100 | struct inode *inode = file->f_path.dentry->d_inode; | |
1101 | ||
1102 | if (is_bad_inode(inode)) | |
1103 | return -EIO; | |
1104 | ||
1105 | res = fuse_direct_io(file, buf, count, ppos, 0); | |
1106 | ||
1107 | fuse_invalidate_attr(inode); | |
1108 | ||
1109 | return res; | |
413ef8cb MS |
1110 | } |
1111 | ||
1112 | static ssize_t fuse_direct_write(struct file *file, const char __user *buf, | |
1113 | size_t count, loff_t *ppos) | |
1114 | { | |
7706a9d6 | 1115 | struct inode *inode = file->f_path.dentry->d_inode; |
413ef8cb | 1116 | ssize_t res; |
d09cb9d7 MS |
1117 | |
1118 | if (is_bad_inode(inode)) | |
1119 | return -EIO; | |
1120 | ||
413ef8cb | 1121 | /* Don't allow parallel writes to the same file */ |
1b1dcc1b | 1122 | mutex_lock(&inode->i_mutex); |
889f7848 | 1123 | res = generic_write_checks(file, ppos, &count, 0); |
d09cb9d7 | 1124 | if (!res) { |
889f7848 | 1125 | res = fuse_direct_io(file, buf, count, ppos, 1); |
d09cb9d7 MS |
1126 | if (res > 0) |
1127 | fuse_write_update_size(inode, *ppos); | |
1128 | } | |
1b1dcc1b | 1129 | mutex_unlock(&inode->i_mutex); |
d09cb9d7 MS |
1130 | |
1131 | fuse_invalidate_attr(inode); | |
1132 | ||
413ef8cb MS |
1133 | return res; |
1134 | } | |
1135 | ||
3be5a52b | 1136 | static void fuse_writepage_free(struct fuse_conn *fc, struct fuse_req *req) |
b6aeaded | 1137 | { |
3be5a52b MS |
1138 | __free_page(req->pages[0]); |
1139 | fuse_file_put(req->ff); | |
3be5a52b MS |
1140 | } |
1141 | ||
1142 | static void fuse_writepage_finish(struct fuse_conn *fc, struct fuse_req *req) | |
1143 | { | |
1144 | struct inode *inode = req->inode; | |
1145 | struct fuse_inode *fi = get_fuse_inode(inode); | |
1146 | struct backing_dev_info *bdi = inode->i_mapping->backing_dev_info; | |
1147 | ||
1148 | list_del(&req->writepages_entry); | |
1149 | dec_bdi_stat(bdi, BDI_WRITEBACK); | |
1150 | dec_zone_page_state(req->pages[0], NR_WRITEBACK_TEMP); | |
1151 | bdi_writeout_inc(bdi); | |
1152 | wake_up(&fi->page_waitq); | |
1153 | } | |
1154 | ||
1155 | /* Called under fc->lock, may release and reacquire it */ | |
1156 | static void fuse_send_writepage(struct fuse_conn *fc, struct fuse_req *req) | |
b9ca67b2 MS |
1157 | __releases(fc->lock) |
1158 | __acquires(fc->lock) | |
3be5a52b MS |
1159 | { |
1160 | struct fuse_inode *fi = get_fuse_inode(req->inode); | |
1161 | loff_t size = i_size_read(req->inode); | |
1162 | struct fuse_write_in *inarg = &req->misc.write.in; | |
1163 | ||
1164 | if (!fc->connected) | |
1165 | goto out_free; | |
1166 | ||
1167 | if (inarg->offset + PAGE_CACHE_SIZE <= size) { | |
1168 | inarg->size = PAGE_CACHE_SIZE; | |
1169 | } else if (inarg->offset < size) { | |
1170 | inarg->size = size & (PAGE_CACHE_SIZE - 1); | |
1171 | } else { | |
1172 | /* Got truncated off completely */ | |
1173 | goto out_free; | |
b6aeaded | 1174 | } |
3be5a52b MS |
1175 | |
1176 | req->in.args[1].size = inarg->size; | |
1177 | fi->writectr++; | |
b93f858a | 1178 | fuse_request_send_background_locked(fc, req); |
3be5a52b MS |
1179 | return; |
1180 | ||
1181 | out_free: | |
1182 | fuse_writepage_finish(fc, req); | |
1183 | spin_unlock(&fc->lock); | |
1184 | fuse_writepage_free(fc, req); | |
e9bb09dd | 1185 | fuse_put_request(fc, req); |
3be5a52b | 1186 | spin_lock(&fc->lock); |
b6aeaded MS |
1187 | } |
1188 | ||
3be5a52b MS |
1189 | /* |
1190 | * If fi->writectr is positive (no truncate or fsync going on) send | |
1191 | * all queued writepage requests. | |
1192 | * | |
1193 | * Called with fc->lock | |
1194 | */ | |
1195 | void fuse_flush_writepages(struct inode *inode) | |
b9ca67b2 MS |
1196 | __releases(fc->lock) |
1197 | __acquires(fc->lock) | |
b6aeaded | 1198 | { |
3be5a52b MS |
1199 | struct fuse_conn *fc = get_fuse_conn(inode); |
1200 | struct fuse_inode *fi = get_fuse_inode(inode); | |
1201 | struct fuse_req *req; | |
1202 | ||
1203 | while (fi->writectr >= 0 && !list_empty(&fi->queued_writes)) { | |
1204 | req = list_entry(fi->queued_writes.next, struct fuse_req, list); | |
1205 | list_del_init(&req->list); | |
1206 | fuse_send_writepage(fc, req); | |
1207 | } | |
1208 | } | |
1209 | ||
1210 | static void fuse_writepage_end(struct fuse_conn *fc, struct fuse_req *req) | |
1211 | { | |
1212 | struct inode *inode = req->inode; | |
1213 | struct fuse_inode *fi = get_fuse_inode(inode); | |
1214 | ||
1215 | mapping_set_error(inode->i_mapping, req->out.h.error); | |
1216 | spin_lock(&fc->lock); | |
1217 | fi->writectr--; | |
1218 | fuse_writepage_finish(fc, req); | |
1219 | spin_unlock(&fc->lock); | |
1220 | fuse_writepage_free(fc, req); | |
1221 | } | |
1222 | ||
1223 | static int fuse_writepage_locked(struct page *page) | |
1224 | { | |
1225 | struct address_space *mapping = page->mapping; | |
1226 | struct inode *inode = mapping->host; | |
1227 | struct fuse_conn *fc = get_fuse_conn(inode); | |
1228 | struct fuse_inode *fi = get_fuse_inode(inode); | |
1229 | struct fuse_req *req; | |
1230 | struct fuse_file *ff; | |
1231 | struct page *tmp_page; | |
1232 | ||
1233 | set_page_writeback(page); | |
1234 | ||
1235 | req = fuse_request_alloc_nofs(); | |
1236 | if (!req) | |
1237 | goto err; | |
1238 | ||
1239 | tmp_page = alloc_page(GFP_NOFS | __GFP_HIGHMEM); | |
1240 | if (!tmp_page) | |
1241 | goto err_free; | |
1242 | ||
1243 | spin_lock(&fc->lock); | |
1244 | BUG_ON(list_empty(&fi->write_files)); | |
1245 | ff = list_entry(fi->write_files.next, struct fuse_file, write_entry); | |
1246 | req->ff = fuse_file_get(ff); | |
1247 | spin_unlock(&fc->lock); | |
1248 | ||
2106cb18 | 1249 | fuse_write_fill(req, ff, page_offset(page), 0); |
3be5a52b MS |
1250 | |
1251 | copy_highpage(tmp_page, page); | |
2d698b07 | 1252 | req->misc.write.in.write_flags |= FUSE_WRITE_CACHE; |
f4975c67 | 1253 | req->in.argpages = 1; |
3be5a52b MS |
1254 | req->num_pages = 1; |
1255 | req->pages[0] = tmp_page; | |
1256 | req->page_offset = 0; | |
1257 | req->end = fuse_writepage_end; | |
1258 | req->inode = inode; | |
1259 | ||
1260 | inc_bdi_stat(mapping->backing_dev_info, BDI_WRITEBACK); | |
1261 | inc_zone_page_state(tmp_page, NR_WRITEBACK_TEMP); | |
1262 | end_page_writeback(page); | |
1263 | ||
1264 | spin_lock(&fc->lock); | |
1265 | list_add(&req->writepages_entry, &fi->writepages); | |
1266 | list_add_tail(&req->list, &fi->queued_writes); | |
1267 | fuse_flush_writepages(inode); | |
1268 | spin_unlock(&fc->lock); | |
1269 | ||
1270 | return 0; | |
1271 | ||
1272 | err_free: | |
1273 | fuse_request_free(req); | |
1274 | err: | |
1275 | end_page_writeback(page); | |
1276 | return -ENOMEM; | |
1277 | } | |
1278 | ||
1279 | static int fuse_writepage(struct page *page, struct writeback_control *wbc) | |
1280 | { | |
1281 | int err; | |
1282 | ||
1283 | err = fuse_writepage_locked(page); | |
1284 | unlock_page(page); | |
1285 | ||
1286 | return err; | |
1287 | } | |
1288 | ||
1289 | static int fuse_launder_page(struct page *page) | |
1290 | { | |
1291 | int err = 0; | |
1292 | if (clear_page_dirty_for_io(page)) { | |
1293 | struct inode *inode = page->mapping->host; | |
1294 | err = fuse_writepage_locked(page); | |
1295 | if (!err) | |
1296 | fuse_wait_on_page_writeback(inode, page->index); | |
1297 | } | |
1298 | return err; | |
1299 | } | |
1300 | ||
1301 | /* | |
1302 | * Write back dirty pages now, because there may not be any suitable | |
1303 | * open files later | |
1304 | */ | |
1305 | static void fuse_vma_close(struct vm_area_struct *vma) | |
1306 | { | |
1307 | filemap_write_and_wait(vma->vm_file->f_mapping); | |
1308 | } | |
1309 | ||
1310 | /* | |
1311 | * Wait for writeback against this page to complete before allowing it | |
1312 | * to be marked dirty again, and hence written back again, possibly | |
1313 | * before the previous writepage completed. | |
1314 | * | |
1315 | * Block here, instead of in ->writepage(), so that the userspace fs | |
1316 | * can only block processes actually operating on the filesystem. | |
1317 | * | |
1318 | * Otherwise unprivileged userspace fs would be able to block | |
1319 | * unrelated: | |
1320 | * | |
1321 | * - page migration | |
1322 | * - sync(2) | |
1323 | * - try_to_free_pages() with order > PAGE_ALLOC_COSTLY_ORDER | |
1324 | */ | |
c2ec175c | 1325 | static int fuse_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) |
3be5a52b | 1326 | { |
c2ec175c | 1327 | struct page *page = vmf->page; |
3be5a52b MS |
1328 | /* |
1329 | * Don't use page->mapping as it may become NULL from a | |
1330 | * concurrent truncate. | |
1331 | */ | |
1332 | struct inode *inode = vma->vm_file->f_mapping->host; | |
1333 | ||
1334 | fuse_wait_on_page_writeback(inode, page->index); | |
1335 | return 0; | |
1336 | } | |
1337 | ||
f0f37e2f | 1338 | static const struct vm_operations_struct fuse_file_vm_ops = { |
3be5a52b MS |
1339 | .close = fuse_vma_close, |
1340 | .fault = filemap_fault, | |
1341 | .page_mkwrite = fuse_page_mkwrite, | |
1342 | }; | |
1343 | ||
1344 | static int fuse_file_mmap(struct file *file, struct vm_area_struct *vma) | |
1345 | { | |
1346 | if ((vma->vm_flags & VM_SHARED) && (vma->vm_flags & VM_MAYWRITE)) { | |
1347 | struct inode *inode = file->f_dentry->d_inode; | |
1348 | struct fuse_conn *fc = get_fuse_conn(inode); | |
1349 | struct fuse_inode *fi = get_fuse_inode(inode); | |
1350 | struct fuse_file *ff = file->private_data; | |
1351 | /* | |
1352 | * file may be written through mmap, so chain it onto the | |
1353 | * inodes's write_file list | |
1354 | */ | |
1355 | spin_lock(&fc->lock); | |
1356 | if (list_empty(&ff->write_entry)) | |
1357 | list_add(&ff->write_entry, &fi->write_files); | |
1358 | spin_unlock(&fc->lock); | |
1359 | } | |
1360 | file_accessed(file); | |
1361 | vma->vm_ops = &fuse_file_vm_ops; | |
b6aeaded MS |
1362 | return 0; |
1363 | } | |
1364 | ||
fc280c96 MS |
1365 | static int fuse_direct_mmap(struct file *file, struct vm_area_struct *vma) |
1366 | { | |
1367 | /* Can't provide the coherency needed for MAP_SHARED */ | |
1368 | if (vma->vm_flags & VM_MAYSHARE) | |
1369 | return -ENODEV; | |
1370 | ||
3121bfe7 MS |
1371 | invalidate_inode_pages2(file->f_mapping); |
1372 | ||
fc280c96 MS |
1373 | return generic_file_mmap(file, vma); |
1374 | } | |
1375 | ||
71421259 MS |
1376 | static int convert_fuse_file_lock(const struct fuse_file_lock *ffl, |
1377 | struct file_lock *fl) | |
1378 | { | |
1379 | switch (ffl->type) { | |
1380 | case F_UNLCK: | |
1381 | break; | |
1382 | ||
1383 | case F_RDLCK: | |
1384 | case F_WRLCK: | |
1385 | if (ffl->start > OFFSET_MAX || ffl->end > OFFSET_MAX || | |
1386 | ffl->end < ffl->start) | |
1387 | return -EIO; | |
1388 | ||
1389 | fl->fl_start = ffl->start; | |
1390 | fl->fl_end = ffl->end; | |
1391 | fl->fl_pid = ffl->pid; | |
1392 | break; | |
1393 | ||
1394 | default: | |
1395 | return -EIO; | |
1396 | } | |
1397 | fl->fl_type = ffl->type; | |
1398 | return 0; | |
1399 | } | |
1400 | ||
1401 | static void fuse_lk_fill(struct fuse_req *req, struct file *file, | |
a9ff4f87 MS |
1402 | const struct file_lock *fl, int opcode, pid_t pid, |
1403 | int flock) | |
71421259 | 1404 | { |
7706a9d6 | 1405 | struct inode *inode = file->f_path.dentry->d_inode; |
9c8ef561 | 1406 | struct fuse_conn *fc = get_fuse_conn(inode); |
71421259 MS |
1407 | struct fuse_file *ff = file->private_data; |
1408 | struct fuse_lk_in *arg = &req->misc.lk_in; | |
1409 | ||
1410 | arg->fh = ff->fh; | |
9c8ef561 | 1411 | arg->owner = fuse_lock_owner_id(fc, fl->fl_owner); |
71421259 MS |
1412 | arg->lk.start = fl->fl_start; |
1413 | arg->lk.end = fl->fl_end; | |
1414 | arg->lk.type = fl->fl_type; | |
1415 | arg->lk.pid = pid; | |
a9ff4f87 MS |
1416 | if (flock) |
1417 | arg->lk_flags |= FUSE_LK_FLOCK; | |
71421259 MS |
1418 | req->in.h.opcode = opcode; |
1419 | req->in.h.nodeid = get_node_id(inode); | |
1420 | req->in.numargs = 1; | |
1421 | req->in.args[0].size = sizeof(*arg); | |
1422 | req->in.args[0].value = arg; | |
1423 | } | |
1424 | ||
1425 | static int fuse_getlk(struct file *file, struct file_lock *fl) | |
1426 | { | |
7706a9d6 | 1427 | struct inode *inode = file->f_path.dentry->d_inode; |
71421259 MS |
1428 | struct fuse_conn *fc = get_fuse_conn(inode); |
1429 | struct fuse_req *req; | |
1430 | struct fuse_lk_out outarg; | |
1431 | int err; | |
1432 | ||
1433 | req = fuse_get_req(fc); | |
1434 | if (IS_ERR(req)) | |
1435 | return PTR_ERR(req); | |
1436 | ||
a9ff4f87 | 1437 | fuse_lk_fill(req, file, fl, FUSE_GETLK, 0, 0); |
71421259 MS |
1438 | req->out.numargs = 1; |
1439 | req->out.args[0].size = sizeof(outarg); | |
1440 | req->out.args[0].value = &outarg; | |
b93f858a | 1441 | fuse_request_send(fc, req); |
71421259 MS |
1442 | err = req->out.h.error; |
1443 | fuse_put_request(fc, req); | |
1444 | if (!err) | |
1445 | err = convert_fuse_file_lock(&outarg.lk, fl); | |
1446 | ||
1447 | return err; | |
1448 | } | |
1449 | ||
a9ff4f87 | 1450 | static int fuse_setlk(struct file *file, struct file_lock *fl, int flock) |
71421259 | 1451 | { |
7706a9d6 | 1452 | struct inode *inode = file->f_path.dentry->d_inode; |
71421259 MS |
1453 | struct fuse_conn *fc = get_fuse_conn(inode); |
1454 | struct fuse_req *req; | |
1455 | int opcode = (fl->fl_flags & FL_SLEEP) ? FUSE_SETLKW : FUSE_SETLK; | |
1456 | pid_t pid = fl->fl_type != F_UNLCK ? current->tgid : 0; | |
1457 | int err; | |
1458 | ||
48e90761 MS |
1459 | if (fl->fl_lmops && fl->fl_lmops->fl_grant) { |
1460 | /* NLM needs asynchronous locks, which we don't support yet */ | |
1461 | return -ENOLCK; | |
1462 | } | |
1463 | ||
71421259 MS |
1464 | /* Unlock on close is handled by the flush method */ |
1465 | if (fl->fl_flags & FL_CLOSE) | |
1466 | return 0; | |
1467 | ||
1468 | req = fuse_get_req(fc); | |
1469 | if (IS_ERR(req)) | |
1470 | return PTR_ERR(req); | |
1471 | ||
a9ff4f87 | 1472 | fuse_lk_fill(req, file, fl, opcode, pid, flock); |
b93f858a | 1473 | fuse_request_send(fc, req); |
71421259 | 1474 | err = req->out.h.error; |
a4d27e75 MS |
1475 | /* locking is restartable */ |
1476 | if (err == -EINTR) | |
1477 | err = -ERESTARTSYS; | |
71421259 MS |
1478 | fuse_put_request(fc, req); |
1479 | return err; | |
1480 | } | |
1481 | ||
1482 | static int fuse_file_lock(struct file *file, int cmd, struct file_lock *fl) | |
1483 | { | |
7706a9d6 | 1484 | struct inode *inode = file->f_path.dentry->d_inode; |
71421259 MS |
1485 | struct fuse_conn *fc = get_fuse_conn(inode); |
1486 | int err; | |
1487 | ||
48e90761 MS |
1488 | if (cmd == F_CANCELLK) { |
1489 | err = 0; | |
1490 | } else if (cmd == F_GETLK) { | |
71421259 | 1491 | if (fc->no_lock) { |
9d6a8c5c | 1492 | posix_test_lock(file, fl); |
71421259 MS |
1493 | err = 0; |
1494 | } else | |
1495 | err = fuse_getlk(file, fl); | |
1496 | } else { | |
1497 | if (fc->no_lock) | |
48e90761 | 1498 | err = posix_lock_file(file, fl, NULL); |
71421259 | 1499 | else |
a9ff4f87 | 1500 | err = fuse_setlk(file, fl, 0); |
71421259 MS |
1501 | } |
1502 | return err; | |
1503 | } | |
1504 | ||
a9ff4f87 MS |
1505 | static int fuse_file_flock(struct file *file, int cmd, struct file_lock *fl) |
1506 | { | |
1507 | struct inode *inode = file->f_path.dentry->d_inode; | |
1508 | struct fuse_conn *fc = get_fuse_conn(inode); | |
1509 | int err; | |
1510 | ||
1511 | if (fc->no_lock) { | |
1512 | err = flock_lock_file_wait(file, fl); | |
1513 | } else { | |
1514 | /* emulate flock with POSIX locks */ | |
1515 | fl->fl_owner = (fl_owner_t) file; | |
1516 | err = fuse_setlk(file, fl, 1); | |
1517 | } | |
1518 | ||
1519 | return err; | |
1520 | } | |
1521 | ||
b2d2272f MS |
1522 | static sector_t fuse_bmap(struct address_space *mapping, sector_t block) |
1523 | { | |
1524 | struct inode *inode = mapping->host; | |
1525 | struct fuse_conn *fc = get_fuse_conn(inode); | |
1526 | struct fuse_req *req; | |
1527 | struct fuse_bmap_in inarg; | |
1528 | struct fuse_bmap_out outarg; | |
1529 | int err; | |
1530 | ||
1531 | if (!inode->i_sb->s_bdev || fc->no_bmap) | |
1532 | return 0; | |
1533 | ||
1534 | req = fuse_get_req(fc); | |
1535 | if (IS_ERR(req)) | |
1536 | return 0; | |
1537 | ||
1538 | memset(&inarg, 0, sizeof(inarg)); | |
1539 | inarg.block = block; | |
1540 | inarg.blocksize = inode->i_sb->s_blocksize; | |
1541 | req->in.h.opcode = FUSE_BMAP; | |
1542 | req->in.h.nodeid = get_node_id(inode); | |
1543 | req->in.numargs = 1; | |
1544 | req->in.args[0].size = sizeof(inarg); | |
1545 | req->in.args[0].value = &inarg; | |
1546 | req->out.numargs = 1; | |
1547 | req->out.args[0].size = sizeof(outarg); | |
1548 | req->out.args[0].value = &outarg; | |
b93f858a | 1549 | fuse_request_send(fc, req); |
b2d2272f MS |
1550 | err = req->out.h.error; |
1551 | fuse_put_request(fc, req); | |
1552 | if (err == -ENOSYS) | |
1553 | fc->no_bmap = 1; | |
1554 | ||
1555 | return err ? 0 : outarg.block; | |
1556 | } | |
1557 | ||
5559b8f4 MS |
1558 | static loff_t fuse_file_llseek(struct file *file, loff_t offset, int origin) |
1559 | { | |
1560 | loff_t retval; | |
1561 | struct inode *inode = file->f_path.dentry->d_inode; | |
1562 | ||
1563 | mutex_lock(&inode->i_mutex); | |
1564 | switch (origin) { | |
1565 | case SEEK_END: | |
769415c6 MS |
1566 | retval = fuse_update_attributes(inode, NULL, file, NULL); |
1567 | if (retval) | |
5291658d | 1568 | goto exit; |
5559b8f4 MS |
1569 | offset += i_size_read(inode); |
1570 | break; | |
1571 | case SEEK_CUR: | |
1572 | offset += file->f_pos; | |
1573 | } | |
1574 | retval = -EINVAL; | |
1575 | if (offset >= 0 && offset <= inode->i_sb->s_maxbytes) { | |
1576 | if (offset != file->f_pos) { | |
1577 | file->f_pos = offset; | |
1578 | file->f_version = 0; | |
1579 | } | |
1580 | retval = offset; | |
1581 | } | |
5291658d | 1582 | exit: |
5559b8f4 MS |
1583 | mutex_unlock(&inode->i_mutex); |
1584 | return retval; | |
1585 | } | |
1586 | ||
59efec7b TH |
1587 | static int fuse_ioctl_copy_user(struct page **pages, struct iovec *iov, |
1588 | unsigned int nr_segs, size_t bytes, bool to_user) | |
1589 | { | |
1590 | struct iov_iter ii; | |
1591 | int page_idx = 0; | |
1592 | ||
1593 | if (!bytes) | |
1594 | return 0; | |
1595 | ||
1596 | iov_iter_init(&ii, iov, nr_segs, bytes, 0); | |
1597 | ||
1598 | while (iov_iter_count(&ii)) { | |
1599 | struct page *page = pages[page_idx++]; | |
1600 | size_t todo = min_t(size_t, PAGE_SIZE, iov_iter_count(&ii)); | |
4aa0edd2 | 1601 | void *kaddr; |
59efec7b | 1602 | |
4aa0edd2 | 1603 | kaddr = kmap(page); |
59efec7b TH |
1604 | |
1605 | while (todo) { | |
1606 | char __user *uaddr = ii.iov->iov_base + ii.iov_offset; | |
1607 | size_t iov_len = ii.iov->iov_len - ii.iov_offset; | |
1608 | size_t copy = min(todo, iov_len); | |
1609 | size_t left; | |
1610 | ||
1611 | if (!to_user) | |
1612 | left = copy_from_user(kaddr, uaddr, copy); | |
1613 | else | |
1614 | left = copy_to_user(uaddr, kaddr, copy); | |
1615 | ||
1616 | if (unlikely(left)) | |
1617 | return -EFAULT; | |
1618 | ||
1619 | iov_iter_advance(&ii, copy); | |
1620 | todo -= copy; | |
1621 | kaddr += copy; | |
1622 | } | |
1623 | ||
0bd87182 | 1624 | kunmap(page); |
59efec7b TH |
1625 | } |
1626 | ||
1627 | return 0; | |
1628 | } | |
1629 | ||
1630 | /* | |
1631 | * For ioctls, there is no generic way to determine how much memory | |
1632 | * needs to be read and/or written. Furthermore, ioctls are allowed | |
1633 | * to dereference the passed pointer, so the parameter requires deep | |
1634 | * copying but FUSE has no idea whatsoever about what to copy in or | |
1635 | * out. | |
1636 | * | |
1637 | * This is solved by allowing FUSE server to retry ioctl with | |
1638 | * necessary in/out iovecs. Let's assume the ioctl implementation | |
1639 | * needs to read in the following structure. | |
1640 | * | |
1641 | * struct a { | |
1642 | * char *buf; | |
1643 | * size_t buflen; | |
1644 | * } | |
1645 | * | |
1646 | * On the first callout to FUSE server, inarg->in_size and | |
1647 | * inarg->out_size will be NULL; then, the server completes the ioctl | |
1648 | * with FUSE_IOCTL_RETRY set in out->flags, out->in_iovs set to 1 and | |
1649 | * the actual iov array to | |
1650 | * | |
1651 | * { { .iov_base = inarg.arg, .iov_len = sizeof(struct a) } } | |
1652 | * | |
1653 | * which tells FUSE to copy in the requested area and retry the ioctl. | |
1654 | * On the second round, the server has access to the structure and | |
1655 | * from that it can tell what to look for next, so on the invocation, | |
1656 | * it sets FUSE_IOCTL_RETRY, out->in_iovs to 2 and iov array to | |
1657 | * | |
1658 | * { { .iov_base = inarg.arg, .iov_len = sizeof(struct a) }, | |
1659 | * { .iov_base = a.buf, .iov_len = a.buflen } } | |
1660 | * | |
1661 | * FUSE will copy both struct a and the pointed buffer from the | |
1662 | * process doing the ioctl and retry ioctl with both struct a and the | |
1663 | * buffer. | |
1664 | * | |
1665 | * This time, FUSE server has everything it needs and completes ioctl | |
1666 | * without FUSE_IOCTL_RETRY which finishes the ioctl call. | |
1667 | * | |
1668 | * Copying data out works the same way. | |
1669 | * | |
1670 | * Note that if FUSE_IOCTL_UNRESTRICTED is clear, the kernel | |
1671 | * automatically initializes in and out iovs by decoding @cmd with | |
1672 | * _IOC_* macros and the server is not allowed to request RETRY. This | |
1673 | * limits ioctl data transfers to well-formed ioctls and is the forced | |
1674 | * behavior for all FUSE servers. | |
1675 | */ | |
08cbf542 TH |
1676 | long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg, |
1677 | unsigned int flags) | |
59efec7b | 1678 | { |
59efec7b | 1679 | struct fuse_file *ff = file->private_data; |
d36f2487 | 1680 | struct fuse_conn *fc = ff->fc; |
59efec7b TH |
1681 | struct fuse_ioctl_in inarg = { |
1682 | .fh = ff->fh, | |
1683 | .cmd = cmd, | |
1684 | .arg = arg, | |
1685 | .flags = flags | |
1686 | }; | |
1687 | struct fuse_ioctl_out outarg; | |
1688 | struct fuse_req *req = NULL; | |
1689 | struct page **pages = NULL; | |
1690 | struct page *iov_page = NULL; | |
1691 | struct iovec *in_iov = NULL, *out_iov = NULL; | |
1692 | unsigned int in_iovs = 0, out_iovs = 0, num_pages = 0, max_pages; | |
1693 | size_t in_size, out_size, transferred; | |
1694 | int err; | |
1695 | ||
1696 | /* assume all the iovs returned by client always fits in a page */ | |
1697 | BUILD_BUG_ON(sizeof(struct iovec) * FUSE_IOCTL_MAX_IOV > PAGE_SIZE); | |
1698 | ||
59efec7b TH |
1699 | err = -ENOMEM; |
1700 | pages = kzalloc(sizeof(pages[0]) * FUSE_MAX_PAGES_PER_REQ, GFP_KERNEL); | |
1701 | iov_page = alloc_page(GFP_KERNEL); | |
1702 | if (!pages || !iov_page) | |
1703 | goto out; | |
1704 | ||
1705 | /* | |
1706 | * If restricted, initialize IO parameters as encoded in @cmd. | |
1707 | * RETRY from server is not allowed. | |
1708 | */ | |
1709 | if (!(flags & FUSE_IOCTL_UNRESTRICTED)) { | |
1710 | struct iovec *iov = page_address(iov_page); | |
1711 | ||
c9f0523d | 1712 | iov->iov_base = (void __user *)arg; |
59efec7b TH |
1713 | iov->iov_len = _IOC_SIZE(cmd); |
1714 | ||
1715 | if (_IOC_DIR(cmd) & _IOC_WRITE) { | |
1716 | in_iov = iov; | |
1717 | in_iovs = 1; | |
1718 | } | |
1719 | ||
1720 | if (_IOC_DIR(cmd) & _IOC_READ) { | |
1721 | out_iov = iov; | |
1722 | out_iovs = 1; | |
1723 | } | |
1724 | } | |
1725 | ||
1726 | retry: | |
1727 | inarg.in_size = in_size = iov_length(in_iov, in_iovs); | |
1728 | inarg.out_size = out_size = iov_length(out_iov, out_iovs); | |
1729 | ||
1730 | /* | |
1731 | * Out data can be used either for actual out data or iovs, | |
1732 | * make sure there always is at least one page. | |
1733 | */ | |
1734 | out_size = max_t(size_t, out_size, PAGE_SIZE); | |
1735 | max_pages = DIV_ROUND_UP(max(in_size, out_size), PAGE_SIZE); | |
1736 | ||
1737 | /* make sure there are enough buffer pages and init request with them */ | |
1738 | err = -ENOMEM; | |
1739 | if (max_pages > FUSE_MAX_PAGES_PER_REQ) | |
1740 | goto out; | |
1741 | while (num_pages < max_pages) { | |
1742 | pages[num_pages] = alloc_page(GFP_KERNEL | __GFP_HIGHMEM); | |
1743 | if (!pages[num_pages]) | |
1744 | goto out; | |
1745 | num_pages++; | |
1746 | } | |
1747 | ||
1748 | req = fuse_get_req(fc); | |
1749 | if (IS_ERR(req)) { | |
1750 | err = PTR_ERR(req); | |
1751 | req = NULL; | |
1752 | goto out; | |
1753 | } | |
1754 | memcpy(req->pages, pages, sizeof(req->pages[0]) * num_pages); | |
1755 | req->num_pages = num_pages; | |
1756 | ||
1757 | /* okay, let's send it to the client */ | |
1758 | req->in.h.opcode = FUSE_IOCTL; | |
d36f2487 | 1759 | req->in.h.nodeid = ff->nodeid; |
59efec7b TH |
1760 | req->in.numargs = 1; |
1761 | req->in.args[0].size = sizeof(inarg); | |
1762 | req->in.args[0].value = &inarg; | |
1763 | if (in_size) { | |
1764 | req->in.numargs++; | |
1765 | req->in.args[1].size = in_size; | |
1766 | req->in.argpages = 1; | |
1767 | ||
1768 | err = fuse_ioctl_copy_user(pages, in_iov, in_iovs, in_size, | |
1769 | false); | |
1770 | if (err) | |
1771 | goto out; | |
1772 | } | |
1773 | ||
1774 | req->out.numargs = 2; | |
1775 | req->out.args[0].size = sizeof(outarg); | |
1776 | req->out.args[0].value = &outarg; | |
1777 | req->out.args[1].size = out_size; | |
1778 | req->out.argpages = 1; | |
1779 | req->out.argvar = 1; | |
1780 | ||
b93f858a | 1781 | fuse_request_send(fc, req); |
59efec7b TH |
1782 | err = req->out.h.error; |
1783 | transferred = req->out.args[1].size; | |
1784 | fuse_put_request(fc, req); | |
1785 | req = NULL; | |
1786 | if (err) | |
1787 | goto out; | |
1788 | ||
1789 | /* did it ask for retry? */ | |
1790 | if (outarg.flags & FUSE_IOCTL_RETRY) { | |
1791 | char *vaddr; | |
1792 | ||
1793 | /* no retry if in restricted mode */ | |
1794 | err = -EIO; | |
1795 | if (!(flags & FUSE_IOCTL_UNRESTRICTED)) | |
1796 | goto out; | |
1797 | ||
1798 | in_iovs = outarg.in_iovs; | |
1799 | out_iovs = outarg.out_iovs; | |
1800 | ||
1801 | /* | |
1802 | * Make sure things are in boundary, separate checks | |
1803 | * are to protect against overflow. | |
1804 | */ | |
1805 | err = -ENOMEM; | |
1806 | if (in_iovs > FUSE_IOCTL_MAX_IOV || | |
1807 | out_iovs > FUSE_IOCTL_MAX_IOV || | |
1808 | in_iovs + out_iovs > FUSE_IOCTL_MAX_IOV) | |
1809 | goto out; | |
1810 | ||
1811 | err = -EIO; | |
1812 | if ((in_iovs + out_iovs) * sizeof(struct iovec) != transferred) | |
1813 | goto out; | |
1814 | ||
1815 | /* okay, copy in iovs and retry */ | |
1816 | vaddr = kmap_atomic(pages[0], KM_USER0); | |
1817 | memcpy(page_address(iov_page), vaddr, transferred); | |
1818 | kunmap_atomic(vaddr, KM_USER0); | |
1819 | ||
1820 | in_iov = page_address(iov_page); | |
1821 | out_iov = in_iov + in_iovs; | |
1822 | ||
1823 | goto retry; | |
1824 | } | |
1825 | ||
1826 | err = -EIO; | |
1827 | if (transferred > inarg.out_size) | |
1828 | goto out; | |
1829 | ||
1830 | err = fuse_ioctl_copy_user(pages, out_iov, out_iovs, transferred, true); | |
1831 | out: | |
1832 | if (req) | |
1833 | fuse_put_request(fc, req); | |
1834 | if (iov_page) | |
1835 | __free_page(iov_page); | |
1836 | while (num_pages) | |
1837 | __free_page(pages[--num_pages]); | |
1838 | kfree(pages); | |
1839 | ||
1840 | return err ? err : outarg.result; | |
1841 | } | |
08cbf542 | 1842 | EXPORT_SYMBOL_GPL(fuse_do_ioctl); |
59efec7b | 1843 | |
d36f2487 MS |
1844 | static long fuse_file_ioctl_common(struct file *file, unsigned int cmd, |
1845 | unsigned long arg, unsigned int flags) | |
1846 | { | |
1847 | struct inode *inode = file->f_dentry->d_inode; | |
1848 | struct fuse_conn *fc = get_fuse_conn(inode); | |
1849 | ||
1850 | if (!fuse_allow_task(fc, current)) | |
1851 | return -EACCES; | |
1852 | ||
1853 | if (is_bad_inode(inode)) | |
1854 | return -EIO; | |
1855 | ||
1856 | return fuse_do_ioctl(file, cmd, arg, flags); | |
1857 | } | |
1858 | ||
59efec7b TH |
1859 | static long fuse_file_ioctl(struct file *file, unsigned int cmd, |
1860 | unsigned long arg) | |
1861 | { | |
d36f2487 | 1862 | return fuse_file_ioctl_common(file, cmd, arg, 0); |
59efec7b TH |
1863 | } |
1864 | ||
1865 | static long fuse_file_compat_ioctl(struct file *file, unsigned int cmd, | |
1866 | unsigned long arg) | |
1867 | { | |
d36f2487 | 1868 | return fuse_file_ioctl_common(file, cmd, arg, FUSE_IOCTL_COMPAT); |
59efec7b TH |
1869 | } |
1870 | ||
95668a69 TH |
1871 | /* |
1872 | * All files which have been polled are linked to RB tree | |
1873 | * fuse_conn->polled_files which is indexed by kh. Walk the tree and | |
1874 | * find the matching one. | |
1875 | */ | |
1876 | static struct rb_node **fuse_find_polled_node(struct fuse_conn *fc, u64 kh, | |
1877 | struct rb_node **parent_out) | |
1878 | { | |
1879 | struct rb_node **link = &fc->polled_files.rb_node; | |
1880 | struct rb_node *last = NULL; | |
1881 | ||
1882 | while (*link) { | |
1883 | struct fuse_file *ff; | |
1884 | ||
1885 | last = *link; | |
1886 | ff = rb_entry(last, struct fuse_file, polled_node); | |
1887 | ||
1888 | if (kh < ff->kh) | |
1889 | link = &last->rb_left; | |
1890 | else if (kh > ff->kh) | |
1891 | link = &last->rb_right; | |
1892 | else | |
1893 | return link; | |
1894 | } | |
1895 | ||
1896 | if (parent_out) | |
1897 | *parent_out = last; | |
1898 | return link; | |
1899 | } | |
1900 | ||
1901 | /* | |
1902 | * The file is about to be polled. Make sure it's on the polled_files | |
1903 | * RB tree. Note that files once added to the polled_files tree are | |
1904 | * not removed before the file is released. This is because a file | |
1905 | * polled once is likely to be polled again. | |
1906 | */ | |
1907 | static void fuse_register_polled_file(struct fuse_conn *fc, | |
1908 | struct fuse_file *ff) | |
1909 | { | |
1910 | spin_lock(&fc->lock); | |
1911 | if (RB_EMPTY_NODE(&ff->polled_node)) { | |
1912 | struct rb_node **link, *parent; | |
1913 | ||
1914 | link = fuse_find_polled_node(fc, ff->kh, &parent); | |
1915 | BUG_ON(*link); | |
1916 | rb_link_node(&ff->polled_node, parent, link); | |
1917 | rb_insert_color(&ff->polled_node, &fc->polled_files); | |
1918 | } | |
1919 | spin_unlock(&fc->lock); | |
1920 | } | |
1921 | ||
08cbf542 | 1922 | unsigned fuse_file_poll(struct file *file, poll_table *wait) |
95668a69 | 1923 | { |
95668a69 | 1924 | struct fuse_file *ff = file->private_data; |
797759aa | 1925 | struct fuse_conn *fc = ff->fc; |
95668a69 TH |
1926 | struct fuse_poll_in inarg = { .fh = ff->fh, .kh = ff->kh }; |
1927 | struct fuse_poll_out outarg; | |
1928 | struct fuse_req *req; | |
1929 | int err; | |
1930 | ||
1931 | if (fc->no_poll) | |
1932 | return DEFAULT_POLLMASK; | |
1933 | ||
1934 | poll_wait(file, &ff->poll_wait, wait); | |
1935 | ||
1936 | /* | |
1937 | * Ask for notification iff there's someone waiting for it. | |
1938 | * The client may ignore the flag and always notify. | |
1939 | */ | |
1940 | if (waitqueue_active(&ff->poll_wait)) { | |
1941 | inarg.flags |= FUSE_POLL_SCHEDULE_NOTIFY; | |
1942 | fuse_register_polled_file(fc, ff); | |
1943 | } | |
1944 | ||
1945 | req = fuse_get_req(fc); | |
1946 | if (IS_ERR(req)) | |
201fa69a | 1947 | return POLLERR; |
95668a69 TH |
1948 | |
1949 | req->in.h.opcode = FUSE_POLL; | |
797759aa | 1950 | req->in.h.nodeid = ff->nodeid; |
95668a69 TH |
1951 | req->in.numargs = 1; |
1952 | req->in.args[0].size = sizeof(inarg); | |
1953 | req->in.args[0].value = &inarg; | |
1954 | req->out.numargs = 1; | |
1955 | req->out.args[0].size = sizeof(outarg); | |
1956 | req->out.args[0].value = &outarg; | |
b93f858a | 1957 | fuse_request_send(fc, req); |
95668a69 TH |
1958 | err = req->out.h.error; |
1959 | fuse_put_request(fc, req); | |
1960 | ||
1961 | if (!err) | |
1962 | return outarg.revents; | |
1963 | if (err == -ENOSYS) { | |
1964 | fc->no_poll = 1; | |
1965 | return DEFAULT_POLLMASK; | |
1966 | } | |
1967 | return POLLERR; | |
1968 | } | |
08cbf542 | 1969 | EXPORT_SYMBOL_GPL(fuse_file_poll); |
95668a69 TH |
1970 | |
1971 | /* | |
1972 | * This is called from fuse_handle_notify() on FUSE_NOTIFY_POLL and | |
1973 | * wakes up the poll waiters. | |
1974 | */ | |
1975 | int fuse_notify_poll_wakeup(struct fuse_conn *fc, | |
1976 | struct fuse_notify_poll_wakeup_out *outarg) | |
1977 | { | |
1978 | u64 kh = outarg->kh; | |
1979 | struct rb_node **link; | |
1980 | ||
1981 | spin_lock(&fc->lock); | |
1982 | ||
1983 | link = fuse_find_polled_node(fc, kh, NULL); | |
1984 | if (*link) { | |
1985 | struct fuse_file *ff; | |
1986 | ||
1987 | ff = rb_entry(*link, struct fuse_file, polled_node); | |
1988 | wake_up_interruptible_sync(&ff->poll_wait); | |
1989 | } | |
1990 | ||
1991 | spin_unlock(&fc->lock); | |
1992 | return 0; | |
1993 | } | |
1994 | ||
4b6f5d20 | 1995 | static const struct file_operations fuse_file_operations = { |
5559b8f4 | 1996 | .llseek = fuse_file_llseek, |
543ade1f | 1997 | .read = do_sync_read, |
bcb4be80 | 1998 | .aio_read = fuse_file_aio_read, |
543ade1f | 1999 | .write = do_sync_write, |
ea9b9907 | 2000 | .aio_write = fuse_file_aio_write, |
b6aeaded MS |
2001 | .mmap = fuse_file_mmap, |
2002 | .open = fuse_open, | |
2003 | .flush = fuse_flush, | |
2004 | .release = fuse_release, | |
2005 | .fsync = fuse_fsync, | |
71421259 | 2006 | .lock = fuse_file_lock, |
a9ff4f87 | 2007 | .flock = fuse_file_flock, |
5ffc4ef4 | 2008 | .splice_read = generic_file_splice_read, |
59efec7b TH |
2009 | .unlocked_ioctl = fuse_file_ioctl, |
2010 | .compat_ioctl = fuse_file_compat_ioctl, | |
95668a69 | 2011 | .poll = fuse_file_poll, |
b6aeaded MS |
2012 | }; |
2013 | ||
4b6f5d20 | 2014 | static const struct file_operations fuse_direct_io_file_operations = { |
5559b8f4 | 2015 | .llseek = fuse_file_llseek, |
413ef8cb MS |
2016 | .read = fuse_direct_read, |
2017 | .write = fuse_direct_write, | |
fc280c96 | 2018 | .mmap = fuse_direct_mmap, |
413ef8cb MS |
2019 | .open = fuse_open, |
2020 | .flush = fuse_flush, | |
2021 | .release = fuse_release, | |
2022 | .fsync = fuse_fsync, | |
71421259 | 2023 | .lock = fuse_file_lock, |
a9ff4f87 | 2024 | .flock = fuse_file_flock, |
59efec7b TH |
2025 | .unlocked_ioctl = fuse_file_ioctl, |
2026 | .compat_ioctl = fuse_file_compat_ioctl, | |
95668a69 | 2027 | .poll = fuse_file_poll, |
fc280c96 | 2028 | /* no splice_read */ |
413ef8cb MS |
2029 | }; |
2030 | ||
f5e54d6e | 2031 | static const struct address_space_operations fuse_file_aops = { |
b6aeaded | 2032 | .readpage = fuse_readpage, |
3be5a52b MS |
2033 | .writepage = fuse_writepage, |
2034 | .launder_page = fuse_launder_page, | |
5e6f58a1 NP |
2035 | .write_begin = fuse_write_begin, |
2036 | .write_end = fuse_write_end, | |
db50b96c | 2037 | .readpages = fuse_readpages, |
3be5a52b | 2038 | .set_page_dirty = __set_page_dirty_nobuffers, |
b2d2272f | 2039 | .bmap = fuse_bmap, |
b6aeaded MS |
2040 | }; |
2041 | ||
2042 | void fuse_init_file_inode(struct inode *inode) | |
2043 | { | |
45323fb7 MS |
2044 | inode->i_fop = &fuse_file_operations; |
2045 | inode->i_data.a_ops = &fuse_file_aops; | |
b6aeaded | 2046 | } |