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Commit | Line | Data |
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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 MS |
136 | struct fuse_file *ff = file->private_data; |
137 | ||
138 | if (ff->open_flags & FOPEN_DIRECT_IO) | |
fd72faac | 139 | file->f_op = &fuse_direct_io_file_operations; |
c7b7143c | 140 | if (!(ff->open_flags & FOPEN_KEEP_CACHE)) |
b1009979 | 141 | invalidate_inode_pages2(inode->i_mapping); |
c7b7143c | 142 | if (ff->open_flags & FOPEN_NONSEEKABLE) |
a7c1b990 | 143 | nonseekable_open(inode, file); |
fd72faac MS |
144 | } |
145 | ||
91fe96b4 | 146 | int fuse_open_common(struct inode *inode, struct file *file, bool isdir) |
fd72faac | 147 | { |
acf99433 | 148 | struct fuse_conn *fc = get_fuse_conn(inode); |
b6aeaded | 149 | int err; |
b6aeaded | 150 | |
dd190d06 MS |
151 | /* VFS checks this, but only _after_ ->open() */ |
152 | if (file->f_flags & O_DIRECT) | |
153 | return -EINVAL; | |
154 | ||
b6aeaded MS |
155 | err = generic_file_open(inode, file); |
156 | if (err) | |
157 | return err; | |
158 | ||
91fe96b4 | 159 | err = fuse_do_open(fc, get_node_id(inode), file, isdir); |
fd72faac | 160 | if (err) |
91fe96b4 | 161 | return err; |
b6aeaded | 162 | |
91fe96b4 MS |
163 | fuse_finish_open(inode, file); |
164 | ||
165 | return 0; | |
b6aeaded MS |
166 | } |
167 | ||
8b0797a4 | 168 | static void fuse_prepare_release(struct fuse_file *ff, int flags, int opcode) |
64c6d8ed | 169 | { |
8b0797a4 | 170 | struct fuse_conn *fc = ff->fc; |
33649c91 | 171 | struct fuse_req *req = ff->reserved_req; |
b57d4264 | 172 | struct fuse_release_in *inarg = &req->misc.release.in; |
b6aeaded | 173 | |
8b0797a4 MS |
174 | spin_lock(&fc->lock); |
175 | list_del(&ff->write_entry); | |
176 | if (!RB_EMPTY_NODE(&ff->polled_node)) | |
177 | rb_erase(&ff->polled_node, &fc->polled_files); | |
178 | spin_unlock(&fc->lock); | |
179 | ||
180 | wake_up_interruptible_sync(&ff->poll_wait); | |
181 | ||
b6aeaded | 182 | inarg->fh = ff->fh; |
fd72faac | 183 | inarg->flags = flags; |
51eb01e7 | 184 | req->in.h.opcode = opcode; |
c7b7143c | 185 | req->in.h.nodeid = ff->nodeid; |
b6aeaded MS |
186 | req->in.numargs = 1; |
187 | req->in.args[0].size = sizeof(struct fuse_release_in); | |
188 | req->in.args[0].value = inarg; | |
fd72faac MS |
189 | } |
190 | ||
8b0797a4 | 191 | void fuse_release_common(struct file *file, int opcode) |
fd72faac | 192 | { |
6b2db28a TH |
193 | struct fuse_file *ff; |
194 | struct fuse_req *req; | |
b6aeaded | 195 | |
6b2db28a TH |
196 | ff = file->private_data; |
197 | if (unlikely(!ff)) | |
8b0797a4 | 198 | return; |
6b2db28a | 199 | |
6b2db28a | 200 | req = ff->reserved_req; |
8b0797a4 | 201 | fuse_prepare_release(ff, file->f_flags, opcode); |
6b2db28a TH |
202 | |
203 | /* Hold vfsmount and dentry until release is finished */ | |
b0be46eb MS |
204 | path_get(&file->f_path); |
205 | req->misc.release.path = file->f_path; | |
6b2db28a | 206 | |
6b2db28a TH |
207 | /* |
208 | * Normally this will send the RELEASE request, however if | |
209 | * some asynchronous READ or WRITE requests are outstanding, | |
210 | * the sending will be delayed. | |
211 | */ | |
212 | fuse_file_put(ff); | |
b6aeaded MS |
213 | } |
214 | ||
04730fef MS |
215 | static int fuse_open(struct inode *inode, struct file *file) |
216 | { | |
91fe96b4 | 217 | return fuse_open_common(inode, file, false); |
04730fef MS |
218 | } |
219 | ||
220 | static int fuse_release(struct inode *inode, struct file *file) | |
221 | { | |
8b0797a4 MS |
222 | fuse_release_common(file, FUSE_RELEASE); |
223 | ||
224 | /* return value is ignored by VFS */ | |
225 | return 0; | |
226 | } | |
227 | ||
228 | void fuse_sync_release(struct fuse_file *ff, int flags) | |
229 | { | |
230 | WARN_ON(atomic_read(&ff->count) > 1); | |
231 | fuse_prepare_release(ff, flags, FUSE_RELEASE); | |
232 | ff->reserved_req->force = 1; | |
233 | fuse_request_send(ff->fc, ff->reserved_req); | |
234 | fuse_put_request(ff->fc, ff->reserved_req); | |
235 | kfree(ff); | |
04730fef | 236 | } |
08cbf542 | 237 | EXPORT_SYMBOL_GPL(fuse_sync_release); |
04730fef | 238 | |
71421259 | 239 | /* |
9c8ef561 MS |
240 | * Scramble the ID space with XTEA, so that the value of the files_struct |
241 | * pointer is not exposed to userspace. | |
71421259 | 242 | */ |
f3332114 | 243 | u64 fuse_lock_owner_id(struct fuse_conn *fc, fl_owner_t id) |
71421259 | 244 | { |
9c8ef561 MS |
245 | u32 *k = fc->scramble_key; |
246 | u64 v = (unsigned long) id; | |
247 | u32 v0 = v; | |
248 | u32 v1 = v >> 32; | |
249 | u32 sum = 0; | |
250 | int i; | |
251 | ||
252 | for (i = 0; i < 32; i++) { | |
253 | v0 += ((v1 << 4 ^ v1 >> 5) + v1) ^ (sum + k[sum & 3]); | |
254 | sum += 0x9E3779B9; | |
255 | v1 += ((v0 << 4 ^ v0 >> 5) + v0) ^ (sum + k[sum>>11 & 3]); | |
256 | } | |
257 | ||
258 | return (u64) v0 + ((u64) v1 << 32); | |
71421259 MS |
259 | } |
260 | ||
3be5a52b MS |
261 | /* |
262 | * Check if page is under writeback | |
263 | * | |
264 | * This is currently done by walking the list of writepage requests | |
265 | * for the inode, which can be pretty inefficient. | |
266 | */ | |
267 | static bool fuse_page_is_writeback(struct inode *inode, pgoff_t index) | |
268 | { | |
269 | struct fuse_conn *fc = get_fuse_conn(inode); | |
270 | struct fuse_inode *fi = get_fuse_inode(inode); | |
271 | struct fuse_req *req; | |
272 | bool found = false; | |
273 | ||
274 | spin_lock(&fc->lock); | |
275 | list_for_each_entry(req, &fi->writepages, writepages_entry) { | |
276 | pgoff_t curr_index; | |
277 | ||
278 | BUG_ON(req->inode != inode); | |
279 | curr_index = req->misc.write.in.offset >> PAGE_CACHE_SHIFT; | |
280 | if (curr_index == index) { | |
281 | found = true; | |
282 | break; | |
283 | } | |
284 | } | |
285 | spin_unlock(&fc->lock); | |
286 | ||
287 | return found; | |
288 | } | |
289 | ||
290 | /* | |
291 | * Wait for page writeback to be completed. | |
292 | * | |
293 | * Since fuse doesn't rely on the VM writeback tracking, this has to | |
294 | * use some other means. | |
295 | */ | |
296 | static int fuse_wait_on_page_writeback(struct inode *inode, pgoff_t index) | |
297 | { | |
298 | struct fuse_inode *fi = get_fuse_inode(inode); | |
299 | ||
300 | wait_event(fi->page_waitq, !fuse_page_is_writeback(inode, index)); | |
301 | return 0; | |
302 | } | |
303 | ||
75e1fcc0 | 304 | static int fuse_flush(struct file *file, fl_owner_t id) |
b6aeaded | 305 | { |
7706a9d6 | 306 | struct inode *inode = file->f_path.dentry->d_inode; |
b6aeaded MS |
307 | struct fuse_conn *fc = get_fuse_conn(inode); |
308 | struct fuse_file *ff = file->private_data; | |
309 | struct fuse_req *req; | |
310 | struct fuse_flush_in inarg; | |
311 | int err; | |
312 | ||
248d86e8 MS |
313 | if (is_bad_inode(inode)) |
314 | return -EIO; | |
315 | ||
b6aeaded MS |
316 | if (fc->no_flush) |
317 | return 0; | |
318 | ||
33649c91 | 319 | req = fuse_get_req_nofail(fc, file); |
b6aeaded MS |
320 | memset(&inarg, 0, sizeof(inarg)); |
321 | inarg.fh = ff->fh; | |
9c8ef561 | 322 | inarg.lock_owner = fuse_lock_owner_id(fc, id); |
b6aeaded MS |
323 | req->in.h.opcode = FUSE_FLUSH; |
324 | req->in.h.nodeid = get_node_id(inode); | |
b6aeaded MS |
325 | req->in.numargs = 1; |
326 | req->in.args[0].size = sizeof(inarg); | |
327 | req->in.args[0].value = &inarg; | |
71421259 | 328 | req->force = 1; |
b93f858a | 329 | fuse_request_send(fc, req); |
b6aeaded MS |
330 | err = req->out.h.error; |
331 | fuse_put_request(fc, req); | |
332 | if (err == -ENOSYS) { | |
333 | fc->no_flush = 1; | |
334 | err = 0; | |
335 | } | |
336 | return err; | |
337 | } | |
338 | ||
3be5a52b MS |
339 | /* |
340 | * Wait for all pending writepages on the inode to finish. | |
341 | * | |
342 | * This is currently done by blocking further writes with FUSE_NOWRITE | |
343 | * and waiting for all sent writes to complete. | |
344 | * | |
345 | * This must be called under i_mutex, otherwise the FUSE_NOWRITE usage | |
346 | * could conflict with truncation. | |
347 | */ | |
348 | static void fuse_sync_writes(struct inode *inode) | |
349 | { | |
350 | fuse_set_nowrite(inode); | |
351 | fuse_release_nowrite(inode); | |
352 | } | |
353 | ||
82547981 MS |
354 | int fuse_fsync_common(struct file *file, struct dentry *de, int datasync, |
355 | int isdir) | |
b6aeaded MS |
356 | { |
357 | struct inode *inode = de->d_inode; | |
358 | struct fuse_conn *fc = get_fuse_conn(inode); | |
359 | struct fuse_file *ff = file->private_data; | |
360 | struct fuse_req *req; | |
361 | struct fuse_fsync_in inarg; | |
362 | int err; | |
363 | ||
248d86e8 MS |
364 | if (is_bad_inode(inode)) |
365 | return -EIO; | |
366 | ||
82547981 | 367 | if ((!isdir && fc->no_fsync) || (isdir && fc->no_fsyncdir)) |
b6aeaded MS |
368 | return 0; |
369 | ||
3be5a52b MS |
370 | /* |
371 | * Start writeback against all dirty pages of the inode, then | |
372 | * wait for all outstanding writes, before sending the FSYNC | |
373 | * request. | |
374 | */ | |
375 | err = write_inode_now(inode, 0); | |
376 | if (err) | |
377 | return err; | |
378 | ||
379 | fuse_sync_writes(inode); | |
380 | ||
ce1d5a49 MS |
381 | req = fuse_get_req(fc); |
382 | if (IS_ERR(req)) | |
383 | return PTR_ERR(req); | |
b6aeaded MS |
384 | |
385 | memset(&inarg, 0, sizeof(inarg)); | |
386 | inarg.fh = ff->fh; | |
387 | inarg.fsync_flags = datasync ? 1 : 0; | |
82547981 | 388 | req->in.h.opcode = isdir ? FUSE_FSYNCDIR : FUSE_FSYNC; |
b6aeaded | 389 | req->in.h.nodeid = get_node_id(inode); |
b6aeaded MS |
390 | req->in.numargs = 1; |
391 | req->in.args[0].size = sizeof(inarg); | |
392 | req->in.args[0].value = &inarg; | |
b93f858a | 393 | fuse_request_send(fc, req); |
b6aeaded MS |
394 | err = req->out.h.error; |
395 | fuse_put_request(fc, req); | |
396 | if (err == -ENOSYS) { | |
82547981 MS |
397 | if (isdir) |
398 | fc->no_fsyncdir = 1; | |
399 | else | |
400 | fc->no_fsync = 1; | |
b6aeaded MS |
401 | err = 0; |
402 | } | |
403 | return err; | |
404 | } | |
405 | ||
82547981 MS |
406 | static int fuse_fsync(struct file *file, struct dentry *de, int datasync) |
407 | { | |
408 | return fuse_fsync_common(file, de, datasync, 0); | |
409 | } | |
410 | ||
2106cb18 MS |
411 | void fuse_read_fill(struct fuse_req *req, struct file *file, loff_t pos, |
412 | size_t count, int opcode) | |
b6aeaded | 413 | { |
5c5c5e51 | 414 | struct fuse_read_in *inarg = &req->misc.read.in; |
a6643094 | 415 | struct fuse_file *ff = file->private_data; |
b6aeaded | 416 | |
361b1eb5 MS |
417 | inarg->fh = ff->fh; |
418 | inarg->offset = pos; | |
419 | inarg->size = count; | |
a6643094 | 420 | inarg->flags = file->f_flags; |
361b1eb5 | 421 | req->in.h.opcode = opcode; |
2106cb18 | 422 | req->in.h.nodeid = ff->nodeid; |
b6aeaded MS |
423 | req->in.numargs = 1; |
424 | req->in.args[0].size = sizeof(struct fuse_read_in); | |
c1aa96a5 | 425 | req->in.args[0].value = inarg; |
b6aeaded MS |
426 | req->out.argvar = 1; |
427 | req->out.numargs = 1; | |
428 | req->out.args[0].size = count; | |
b6aeaded MS |
429 | } |
430 | ||
8bfc016d | 431 | static size_t fuse_send_read(struct fuse_req *req, struct file *file, |
2106cb18 | 432 | loff_t pos, size_t count, fl_owner_t owner) |
04730fef | 433 | { |
2106cb18 MS |
434 | struct fuse_file *ff = file->private_data; |
435 | struct fuse_conn *fc = ff->fc; | |
f3332114 | 436 | |
2106cb18 | 437 | fuse_read_fill(req, file, pos, count, FUSE_READ); |
f3332114 | 438 | if (owner != NULL) { |
5c5c5e51 | 439 | struct fuse_read_in *inarg = &req->misc.read.in; |
f3332114 MS |
440 | |
441 | inarg->read_flags |= FUSE_READ_LOCKOWNER; | |
442 | inarg->lock_owner = fuse_lock_owner_id(fc, owner); | |
443 | } | |
b93f858a | 444 | fuse_request_send(fc, req); |
361b1eb5 | 445 | return req->out.args[0].size; |
04730fef MS |
446 | } |
447 | ||
5c5c5e51 MS |
448 | static void fuse_read_update_size(struct inode *inode, loff_t size, |
449 | u64 attr_ver) | |
450 | { | |
451 | struct fuse_conn *fc = get_fuse_conn(inode); | |
452 | struct fuse_inode *fi = get_fuse_inode(inode); | |
453 | ||
454 | spin_lock(&fc->lock); | |
455 | if (attr_ver == fi->attr_version && size < inode->i_size) { | |
456 | fi->attr_version = ++fc->attr_version; | |
457 | i_size_write(inode, size); | |
458 | } | |
459 | spin_unlock(&fc->lock); | |
460 | } | |
461 | ||
b6aeaded MS |
462 | static int fuse_readpage(struct file *file, struct page *page) |
463 | { | |
464 | struct inode *inode = page->mapping->host; | |
465 | struct fuse_conn *fc = get_fuse_conn(inode); | |
248d86e8 | 466 | struct fuse_req *req; |
5c5c5e51 MS |
467 | size_t num_read; |
468 | loff_t pos = page_offset(page); | |
469 | size_t count = PAGE_CACHE_SIZE; | |
470 | u64 attr_ver; | |
248d86e8 MS |
471 | int err; |
472 | ||
473 | err = -EIO; | |
474 | if (is_bad_inode(inode)) | |
475 | goto out; | |
476 | ||
3be5a52b MS |
477 | /* |
478 | * Page writeback can extend beyond the liftime of the | |
479 | * page-cache page, so make sure we read a properly synced | |
480 | * page. | |
481 | */ | |
482 | fuse_wait_on_page_writeback(inode, page->index); | |
483 | ||
ce1d5a49 MS |
484 | req = fuse_get_req(fc); |
485 | err = PTR_ERR(req); | |
486 | if (IS_ERR(req)) | |
b6aeaded MS |
487 | goto out; |
488 | ||
5c5c5e51 MS |
489 | attr_ver = fuse_get_attr_version(fc); |
490 | ||
b6aeaded | 491 | req->out.page_zeroing = 1; |
f4975c67 | 492 | req->out.argpages = 1; |
b6aeaded MS |
493 | req->num_pages = 1; |
494 | req->pages[0] = page; | |
2106cb18 | 495 | num_read = fuse_send_read(req, file, pos, count, NULL); |
b6aeaded MS |
496 | err = req->out.h.error; |
497 | fuse_put_request(fc, req); | |
5c5c5e51 MS |
498 | |
499 | if (!err) { | |
500 | /* | |
501 | * Short read means EOF. If file size is larger, truncate it | |
502 | */ | |
503 | if (num_read < count) | |
504 | fuse_read_update_size(inode, pos + num_read, attr_ver); | |
505 | ||
b6aeaded | 506 | SetPageUptodate(page); |
5c5c5e51 MS |
507 | } |
508 | ||
b36c31ba | 509 | fuse_invalidate_attr(inode); /* atime changed */ |
b6aeaded MS |
510 | out: |
511 | unlock_page(page); | |
512 | return err; | |
513 | } | |
514 | ||
c1aa96a5 | 515 | static void fuse_readpages_end(struct fuse_conn *fc, struct fuse_req *req) |
db50b96c | 516 | { |
c1aa96a5 | 517 | int i; |
5c5c5e51 MS |
518 | size_t count = req->misc.read.in.size; |
519 | size_t num_read = req->out.args[0].size; | |
520 | struct inode *inode = req->pages[0]->mapping->host; | |
c1aa96a5 | 521 | |
5c5c5e51 MS |
522 | /* |
523 | * Short read means EOF. If file size is larger, truncate it | |
524 | */ | |
525 | if (!req->out.h.error && num_read < count) { | |
526 | loff_t pos = page_offset(req->pages[0]) + num_read; | |
527 | fuse_read_update_size(inode, pos, req->misc.read.attr_ver); | |
528 | } | |
529 | ||
530 | fuse_invalidate_attr(inode); /* atime changed */ | |
c1aa96a5 | 531 | |
db50b96c MS |
532 | for (i = 0; i < req->num_pages; i++) { |
533 | struct page *page = req->pages[i]; | |
534 | if (!req->out.h.error) | |
535 | SetPageUptodate(page); | |
c1aa96a5 MS |
536 | else |
537 | SetPageError(page); | |
db50b96c MS |
538 | unlock_page(page); |
539 | } | |
c756e0a4 MS |
540 | if (req->ff) |
541 | fuse_file_put(req->ff); | |
c1aa96a5 MS |
542 | } |
543 | ||
2106cb18 | 544 | static void fuse_send_readpages(struct fuse_req *req, struct file *file) |
c1aa96a5 | 545 | { |
2106cb18 MS |
546 | struct fuse_file *ff = file->private_data; |
547 | struct fuse_conn *fc = ff->fc; | |
c1aa96a5 MS |
548 | loff_t pos = page_offset(req->pages[0]); |
549 | size_t count = req->num_pages << PAGE_CACHE_SHIFT; | |
f4975c67 MS |
550 | |
551 | req->out.argpages = 1; | |
c1aa96a5 | 552 | req->out.page_zeroing = 1; |
2106cb18 | 553 | fuse_read_fill(req, file, pos, count, FUSE_READ); |
5c5c5e51 | 554 | req->misc.read.attr_ver = fuse_get_attr_version(fc); |
9cd68455 | 555 | if (fc->async_read) { |
c756e0a4 | 556 | req->ff = fuse_file_get(ff); |
9cd68455 | 557 | req->end = fuse_readpages_end; |
b93f858a | 558 | fuse_request_send_background(fc, req); |
9cd68455 | 559 | } else { |
b93f858a | 560 | fuse_request_send(fc, req); |
9cd68455 | 561 | fuse_readpages_end(fc, req); |
e9bb09dd | 562 | fuse_put_request(fc, req); |
9cd68455 | 563 | } |
db50b96c MS |
564 | } |
565 | ||
c756e0a4 | 566 | struct fuse_fill_data { |
db50b96c | 567 | struct fuse_req *req; |
a6643094 | 568 | struct file *file; |
db50b96c MS |
569 | struct inode *inode; |
570 | }; | |
571 | ||
572 | static int fuse_readpages_fill(void *_data, struct page *page) | |
573 | { | |
c756e0a4 | 574 | struct fuse_fill_data *data = _data; |
db50b96c MS |
575 | struct fuse_req *req = data->req; |
576 | struct inode *inode = data->inode; | |
577 | struct fuse_conn *fc = get_fuse_conn(inode); | |
578 | ||
3be5a52b MS |
579 | fuse_wait_on_page_writeback(inode, page->index); |
580 | ||
db50b96c MS |
581 | if (req->num_pages && |
582 | (req->num_pages == FUSE_MAX_PAGES_PER_REQ || | |
583 | (req->num_pages + 1) * PAGE_CACHE_SIZE > fc->max_read || | |
584 | req->pages[req->num_pages - 1]->index + 1 != page->index)) { | |
2106cb18 | 585 | fuse_send_readpages(req, data->file); |
ce1d5a49 MS |
586 | data->req = req = fuse_get_req(fc); |
587 | if (IS_ERR(req)) { | |
db50b96c | 588 | unlock_page(page); |
ce1d5a49 | 589 | return PTR_ERR(req); |
db50b96c | 590 | } |
db50b96c MS |
591 | } |
592 | req->pages[req->num_pages] = page; | |
1729a16c | 593 | req->num_pages++; |
db50b96c MS |
594 | return 0; |
595 | } | |
596 | ||
597 | static int fuse_readpages(struct file *file, struct address_space *mapping, | |
598 | struct list_head *pages, unsigned nr_pages) | |
599 | { | |
600 | struct inode *inode = mapping->host; | |
601 | struct fuse_conn *fc = get_fuse_conn(inode); | |
c756e0a4 | 602 | struct fuse_fill_data data; |
db50b96c | 603 | int err; |
248d86e8 | 604 | |
1d7ea732 | 605 | err = -EIO; |
248d86e8 | 606 | if (is_bad_inode(inode)) |
2e990021 | 607 | goto out; |
248d86e8 | 608 | |
a6643094 | 609 | data.file = file; |
db50b96c | 610 | data.inode = inode; |
ce1d5a49 | 611 | data.req = fuse_get_req(fc); |
1d7ea732 | 612 | err = PTR_ERR(data.req); |
ce1d5a49 | 613 | if (IS_ERR(data.req)) |
2e990021 | 614 | goto out; |
db50b96c MS |
615 | |
616 | err = read_cache_pages(mapping, pages, fuse_readpages_fill, &data); | |
d3406ffa MS |
617 | if (!err) { |
618 | if (data.req->num_pages) | |
2106cb18 | 619 | fuse_send_readpages(data.req, file); |
d3406ffa MS |
620 | else |
621 | fuse_put_request(fc, data.req); | |
622 | } | |
2e990021 | 623 | out: |
1d7ea732 | 624 | return err; |
db50b96c MS |
625 | } |
626 | ||
bcb4be80 MS |
627 | static ssize_t fuse_file_aio_read(struct kiocb *iocb, const struct iovec *iov, |
628 | unsigned long nr_segs, loff_t pos) | |
629 | { | |
630 | struct inode *inode = iocb->ki_filp->f_mapping->host; | |
631 | ||
632 | if (pos + iov_length(iov, nr_segs) > i_size_read(inode)) { | |
633 | int err; | |
634 | /* | |
635 | * If trying to read past EOF, make sure the i_size | |
636 | * attribute is up-to-date. | |
637 | */ | |
638 | err = fuse_update_attributes(inode, NULL, iocb->ki_filp, NULL); | |
639 | if (err) | |
640 | return err; | |
641 | } | |
642 | ||
643 | return generic_file_aio_read(iocb, iov, nr_segs, pos); | |
644 | } | |
645 | ||
2d698b07 | 646 | static void fuse_write_fill(struct fuse_req *req, struct fuse_file *ff, |
2106cb18 | 647 | loff_t pos, size_t count) |
b6aeaded | 648 | { |
b25e82e5 MS |
649 | struct fuse_write_in *inarg = &req->misc.write.in; |
650 | struct fuse_write_out *outarg = &req->misc.write.out; | |
b6aeaded | 651 | |
b25e82e5 MS |
652 | inarg->fh = ff->fh; |
653 | inarg->offset = pos; | |
654 | inarg->size = count; | |
b6aeaded | 655 | req->in.h.opcode = FUSE_WRITE; |
2106cb18 | 656 | req->in.h.nodeid = ff->nodeid; |
b6aeaded | 657 | req->in.numargs = 2; |
2106cb18 | 658 | if (ff->fc->minor < 9) |
f3332114 MS |
659 | req->in.args[0].size = FUSE_COMPAT_WRITE_IN_SIZE; |
660 | else | |
661 | req->in.args[0].size = sizeof(struct fuse_write_in); | |
b25e82e5 | 662 | req->in.args[0].value = inarg; |
b6aeaded MS |
663 | req->in.args[1].size = count; |
664 | req->out.numargs = 1; | |
665 | req->out.args[0].size = sizeof(struct fuse_write_out); | |
b25e82e5 MS |
666 | req->out.args[0].value = outarg; |
667 | } | |
668 | ||
669 | static size_t fuse_send_write(struct fuse_req *req, struct file *file, | |
2106cb18 | 670 | loff_t pos, size_t count, fl_owner_t owner) |
b25e82e5 | 671 | { |
2106cb18 MS |
672 | struct fuse_file *ff = file->private_data; |
673 | struct fuse_conn *fc = ff->fc; | |
2d698b07 MS |
674 | struct fuse_write_in *inarg = &req->misc.write.in; |
675 | ||
2106cb18 | 676 | fuse_write_fill(req, ff, pos, count); |
2d698b07 | 677 | inarg->flags = file->f_flags; |
f3332114 | 678 | if (owner != NULL) { |
f3332114 MS |
679 | inarg->write_flags |= FUSE_WRITE_LOCKOWNER; |
680 | inarg->lock_owner = fuse_lock_owner_id(fc, owner); | |
681 | } | |
b93f858a | 682 | fuse_request_send(fc, req); |
b25e82e5 | 683 | return req->misc.write.out.size; |
b6aeaded MS |
684 | } |
685 | ||
5e6f58a1 NP |
686 | static int fuse_write_begin(struct file *file, struct address_space *mapping, |
687 | loff_t pos, unsigned len, unsigned flags, | |
688 | struct page **pagep, void **fsdata) | |
b6aeaded | 689 | { |
5e6f58a1 NP |
690 | pgoff_t index = pos >> PAGE_CACHE_SHIFT; |
691 | ||
54566b2c | 692 | *pagep = grab_cache_page_write_begin(mapping, index, flags); |
5e6f58a1 NP |
693 | if (!*pagep) |
694 | return -ENOMEM; | |
b6aeaded MS |
695 | return 0; |
696 | } | |
697 | ||
854512ec MS |
698 | static void fuse_write_update_size(struct inode *inode, loff_t pos) |
699 | { | |
700 | struct fuse_conn *fc = get_fuse_conn(inode); | |
701 | struct fuse_inode *fi = get_fuse_inode(inode); | |
702 | ||
703 | spin_lock(&fc->lock); | |
704 | fi->attr_version = ++fc->attr_version; | |
705 | if (pos > inode->i_size) | |
706 | i_size_write(inode, pos); | |
707 | spin_unlock(&fc->lock); | |
708 | } | |
709 | ||
5e6f58a1 NP |
710 | static int fuse_buffered_write(struct file *file, struct inode *inode, |
711 | loff_t pos, unsigned count, struct page *page) | |
b6aeaded MS |
712 | { |
713 | int err; | |
04730fef | 714 | size_t nres; |
b6aeaded | 715 | struct fuse_conn *fc = get_fuse_conn(inode); |
5e6f58a1 | 716 | unsigned offset = pos & (PAGE_CACHE_SIZE - 1); |
248d86e8 MS |
717 | struct fuse_req *req; |
718 | ||
719 | if (is_bad_inode(inode)) | |
720 | return -EIO; | |
721 | ||
3be5a52b MS |
722 | /* |
723 | * Make sure writepages on the same page are not mixed up with | |
724 | * plain writes. | |
725 | */ | |
726 | fuse_wait_on_page_writeback(inode, page->index); | |
727 | ||
ce1d5a49 MS |
728 | req = fuse_get_req(fc); |
729 | if (IS_ERR(req)) | |
730 | return PTR_ERR(req); | |
b6aeaded | 731 | |
f4975c67 | 732 | req->in.argpages = 1; |
b6aeaded MS |
733 | req->num_pages = 1; |
734 | req->pages[0] = page; | |
735 | req->page_offset = offset; | |
2106cb18 | 736 | nres = fuse_send_write(req, file, pos, count, NULL); |
b6aeaded MS |
737 | err = req->out.h.error; |
738 | fuse_put_request(fc, req); | |
5e6f58a1 | 739 | if (!err && !nres) |
b6aeaded MS |
740 | err = -EIO; |
741 | if (!err) { | |
5e6f58a1 | 742 | pos += nres; |
854512ec | 743 | fuse_write_update_size(inode, pos); |
5e6f58a1 | 744 | if (count == PAGE_CACHE_SIZE) |
b6aeaded | 745 | SetPageUptodate(page); |
b36c31ba MS |
746 | } |
747 | fuse_invalidate_attr(inode); | |
5e6f58a1 NP |
748 | return err ? err : nres; |
749 | } | |
750 | ||
751 | static int fuse_write_end(struct file *file, struct address_space *mapping, | |
752 | loff_t pos, unsigned len, unsigned copied, | |
753 | struct page *page, void *fsdata) | |
754 | { | |
755 | struct inode *inode = mapping->host; | |
756 | int res = 0; | |
757 | ||
758 | if (copied) | |
759 | res = fuse_buffered_write(file, inode, pos, copied, page); | |
760 | ||
761 | unlock_page(page); | |
762 | page_cache_release(page); | |
763 | return res; | |
b6aeaded MS |
764 | } |
765 | ||
ea9b9907 NP |
766 | static size_t fuse_send_write_pages(struct fuse_req *req, struct file *file, |
767 | struct inode *inode, loff_t pos, | |
768 | size_t count) | |
769 | { | |
770 | size_t res; | |
771 | unsigned offset; | |
772 | unsigned i; | |
773 | ||
774 | for (i = 0; i < req->num_pages; i++) | |
775 | fuse_wait_on_page_writeback(inode, req->pages[i]->index); | |
776 | ||
2106cb18 | 777 | res = fuse_send_write(req, file, pos, count, NULL); |
ea9b9907 NP |
778 | |
779 | offset = req->page_offset; | |
780 | count = res; | |
781 | for (i = 0; i < req->num_pages; i++) { | |
782 | struct page *page = req->pages[i]; | |
783 | ||
784 | if (!req->out.h.error && !offset && count >= PAGE_CACHE_SIZE) | |
785 | SetPageUptodate(page); | |
786 | ||
787 | if (count > PAGE_CACHE_SIZE - offset) | |
788 | count -= PAGE_CACHE_SIZE - offset; | |
789 | else | |
790 | count = 0; | |
791 | offset = 0; | |
792 | ||
793 | unlock_page(page); | |
794 | page_cache_release(page); | |
795 | } | |
796 | ||
797 | return res; | |
798 | } | |
799 | ||
800 | static ssize_t fuse_fill_write_pages(struct fuse_req *req, | |
801 | struct address_space *mapping, | |
802 | struct iov_iter *ii, loff_t pos) | |
803 | { | |
804 | struct fuse_conn *fc = get_fuse_conn(mapping->host); | |
805 | unsigned offset = pos & (PAGE_CACHE_SIZE - 1); | |
806 | size_t count = 0; | |
807 | int err; | |
808 | ||
f4975c67 | 809 | req->in.argpages = 1; |
ea9b9907 NP |
810 | req->page_offset = offset; |
811 | ||
812 | do { | |
813 | size_t tmp; | |
814 | struct page *page; | |
815 | pgoff_t index = pos >> PAGE_CACHE_SHIFT; | |
816 | size_t bytes = min_t(size_t, PAGE_CACHE_SIZE - offset, | |
817 | iov_iter_count(ii)); | |
818 | ||
819 | bytes = min_t(size_t, bytes, fc->max_write - count); | |
820 | ||
821 | again: | |
822 | err = -EFAULT; | |
823 | if (iov_iter_fault_in_readable(ii, bytes)) | |
824 | break; | |
825 | ||
826 | err = -ENOMEM; | |
54566b2c | 827 | page = grab_cache_page_write_begin(mapping, index, 0); |
ea9b9907 NP |
828 | if (!page) |
829 | break; | |
830 | ||
831 | pagefault_disable(); | |
832 | tmp = iov_iter_copy_from_user_atomic(page, ii, offset, bytes); | |
833 | pagefault_enable(); | |
834 | flush_dcache_page(page); | |
835 | ||
836 | if (!tmp) { | |
837 | unlock_page(page); | |
838 | page_cache_release(page); | |
839 | bytes = min(bytes, iov_iter_single_seg_count(ii)); | |
840 | goto again; | |
841 | } | |
842 | ||
843 | err = 0; | |
844 | req->pages[req->num_pages] = page; | |
845 | req->num_pages++; | |
846 | ||
847 | iov_iter_advance(ii, tmp); | |
848 | count += tmp; | |
849 | pos += tmp; | |
850 | offset += tmp; | |
851 | if (offset == PAGE_CACHE_SIZE) | |
852 | offset = 0; | |
853 | ||
78bb6cb9 MS |
854 | if (!fc->big_writes) |
855 | break; | |
ea9b9907 NP |
856 | } while (iov_iter_count(ii) && count < fc->max_write && |
857 | req->num_pages < FUSE_MAX_PAGES_PER_REQ && offset == 0); | |
858 | ||
859 | return count > 0 ? count : err; | |
860 | } | |
861 | ||
862 | static ssize_t fuse_perform_write(struct file *file, | |
863 | struct address_space *mapping, | |
864 | struct iov_iter *ii, loff_t pos) | |
865 | { | |
866 | struct inode *inode = mapping->host; | |
867 | struct fuse_conn *fc = get_fuse_conn(inode); | |
868 | int err = 0; | |
869 | ssize_t res = 0; | |
870 | ||
871 | if (is_bad_inode(inode)) | |
872 | return -EIO; | |
873 | ||
874 | do { | |
875 | struct fuse_req *req; | |
876 | ssize_t count; | |
877 | ||
878 | req = fuse_get_req(fc); | |
879 | if (IS_ERR(req)) { | |
880 | err = PTR_ERR(req); | |
881 | break; | |
882 | } | |
883 | ||
884 | count = fuse_fill_write_pages(req, mapping, ii, pos); | |
885 | if (count <= 0) { | |
886 | err = count; | |
887 | } else { | |
888 | size_t num_written; | |
889 | ||
890 | num_written = fuse_send_write_pages(req, file, inode, | |
891 | pos, count); | |
892 | err = req->out.h.error; | |
893 | if (!err) { | |
894 | res += num_written; | |
895 | pos += num_written; | |
896 | ||
897 | /* break out of the loop on short write */ | |
898 | if (num_written != count) | |
899 | err = -EIO; | |
900 | } | |
901 | } | |
902 | fuse_put_request(fc, req); | |
903 | } while (!err && iov_iter_count(ii)); | |
904 | ||
905 | if (res > 0) | |
906 | fuse_write_update_size(inode, pos); | |
907 | ||
908 | fuse_invalidate_attr(inode); | |
909 | ||
910 | return res > 0 ? res : err; | |
911 | } | |
912 | ||
913 | static ssize_t fuse_file_aio_write(struct kiocb *iocb, const struct iovec *iov, | |
914 | unsigned long nr_segs, loff_t pos) | |
915 | { | |
916 | struct file *file = iocb->ki_filp; | |
917 | struct address_space *mapping = file->f_mapping; | |
918 | size_t count = 0; | |
919 | ssize_t written = 0; | |
920 | struct inode *inode = mapping->host; | |
921 | ssize_t err; | |
922 | struct iov_iter i; | |
923 | ||
924 | WARN_ON(iocb->ki_pos != pos); | |
925 | ||
926 | err = generic_segment_checks(iov, &nr_segs, &count, VERIFY_READ); | |
927 | if (err) | |
928 | return err; | |
929 | ||
930 | mutex_lock(&inode->i_mutex); | |
931 | vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE); | |
932 | ||
933 | /* We can write back this queue in page reclaim */ | |
934 | current->backing_dev_info = mapping->backing_dev_info; | |
935 | ||
936 | err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode)); | |
937 | if (err) | |
938 | goto out; | |
939 | ||
940 | if (count == 0) | |
941 | goto out; | |
942 | ||
2f1936b8 | 943 | err = file_remove_suid(file); |
ea9b9907 NP |
944 | if (err) |
945 | goto out; | |
946 | ||
947 | file_update_time(file); | |
948 | ||
949 | iov_iter_init(&i, iov, nr_segs, count, 0); | |
950 | written = fuse_perform_write(file, mapping, &i, pos); | |
951 | if (written >= 0) | |
952 | iocb->ki_pos = pos + written; | |
953 | ||
954 | out: | |
955 | current->backing_dev_info = NULL; | |
956 | mutex_unlock(&inode->i_mutex); | |
957 | ||
958 | return written ? written : err; | |
959 | } | |
960 | ||
413ef8cb MS |
961 | static void fuse_release_user_pages(struct fuse_req *req, int write) |
962 | { | |
963 | unsigned i; | |
964 | ||
965 | for (i = 0; i < req->num_pages; i++) { | |
966 | struct page *page = req->pages[i]; | |
967 | if (write) | |
968 | set_page_dirty_lock(page); | |
969 | put_page(page); | |
970 | } | |
971 | } | |
972 | ||
973 | static int fuse_get_user_pages(struct fuse_req *req, const char __user *buf, | |
ce60a2f1 | 974 | size_t *nbytesp, int write) |
413ef8cb | 975 | { |
ce60a2f1 | 976 | size_t nbytes = *nbytesp; |
413ef8cb MS |
977 | unsigned long user_addr = (unsigned long) buf; |
978 | unsigned offset = user_addr & ~PAGE_MASK; | |
979 | int npages; | |
980 | ||
f4975c67 MS |
981 | /* Special case for kernel I/O: can copy directly into the buffer */ |
982 | if (segment_eq(get_fs(), KERNEL_DS)) { | |
983 | if (write) | |
984 | req->in.args[1].value = (void *) user_addr; | |
985 | else | |
986 | req->out.args[0].value = (void *) user_addr; | |
987 | ||
988 | return 0; | |
989 | } | |
413ef8cb | 990 | |
ce60a2f1 | 991 | nbytes = min_t(size_t, nbytes, FUSE_MAX_PAGES_PER_REQ << PAGE_SHIFT); |
413ef8cb | 992 | npages = (nbytes + offset + PAGE_SIZE - 1) >> PAGE_SHIFT; |
bd730967 | 993 | npages = clamp(npages, 1, FUSE_MAX_PAGES_PER_REQ); |
413ef8cb | 994 | down_read(¤t->mm->mmap_sem); |
f4975c67 | 995 | npages = get_user_pages(current, current->mm, user_addr, npages, !write, |
413ef8cb MS |
996 | 0, req->pages, NULL); |
997 | up_read(¤t->mm->mmap_sem); | |
998 | if (npages < 0) | |
999 | return npages; | |
1000 | ||
1001 | req->num_pages = npages; | |
1002 | req->page_offset = offset; | |
f4975c67 MS |
1003 | |
1004 | if (write) | |
1005 | req->in.argpages = 1; | |
1006 | else | |
1007 | req->out.argpages = 1; | |
1008 | ||
1009 | nbytes = (req->num_pages << PAGE_SHIFT) - req->page_offset; | |
1010 | *nbytesp = min(*nbytesp, nbytes); | |
1011 | ||
413ef8cb MS |
1012 | return 0; |
1013 | } | |
1014 | ||
08cbf542 TH |
1015 | ssize_t fuse_direct_io(struct file *file, const char __user *buf, |
1016 | size_t count, loff_t *ppos, int write) | |
413ef8cb | 1017 | { |
2106cb18 MS |
1018 | struct fuse_file *ff = file->private_data; |
1019 | struct fuse_conn *fc = ff->fc; | |
413ef8cb MS |
1020 | size_t nmax = write ? fc->max_write : fc->max_read; |
1021 | loff_t pos = *ppos; | |
1022 | ssize_t res = 0; | |
248d86e8 MS |
1023 | struct fuse_req *req; |
1024 | ||
ce1d5a49 MS |
1025 | req = fuse_get_req(fc); |
1026 | if (IS_ERR(req)) | |
1027 | return PTR_ERR(req); | |
413ef8cb MS |
1028 | |
1029 | while (count) { | |
413ef8cb | 1030 | size_t nres; |
2106cb18 | 1031 | fl_owner_t owner = current->files; |
f4975c67 MS |
1032 | size_t nbytes = min(count, nmax); |
1033 | int err = fuse_get_user_pages(req, buf, &nbytes, write); | |
413ef8cb MS |
1034 | if (err) { |
1035 | res = err; | |
1036 | break; | |
1037 | } | |
f4975c67 | 1038 | |
413ef8cb | 1039 | if (write) |
2106cb18 | 1040 | nres = fuse_send_write(req, file, pos, nbytes, owner); |
413ef8cb | 1041 | else |
2106cb18 MS |
1042 | nres = fuse_send_read(req, file, pos, nbytes, owner); |
1043 | ||
413ef8cb MS |
1044 | fuse_release_user_pages(req, !write); |
1045 | if (req->out.h.error) { | |
1046 | if (!res) | |
1047 | res = req->out.h.error; | |
1048 | break; | |
1049 | } else if (nres > nbytes) { | |
1050 | res = -EIO; | |
1051 | break; | |
1052 | } | |
1053 | count -= nres; | |
1054 | res += nres; | |
1055 | pos += nres; | |
1056 | buf += nres; | |
1057 | if (nres != nbytes) | |
1058 | break; | |
56cf34ff MS |
1059 | if (count) { |
1060 | fuse_put_request(fc, req); | |
1061 | req = fuse_get_req(fc); | |
1062 | if (IS_ERR(req)) | |
1063 | break; | |
1064 | } | |
413ef8cb | 1065 | } |
f60311d5 AA |
1066 | if (!IS_ERR(req)) |
1067 | fuse_put_request(fc, req); | |
d09cb9d7 | 1068 | if (res > 0) |
413ef8cb | 1069 | *ppos = pos; |
413ef8cb MS |
1070 | |
1071 | return res; | |
1072 | } | |
08cbf542 | 1073 | EXPORT_SYMBOL_GPL(fuse_direct_io); |
413ef8cb MS |
1074 | |
1075 | static ssize_t fuse_direct_read(struct file *file, char __user *buf, | |
1076 | size_t count, loff_t *ppos) | |
1077 | { | |
d09cb9d7 MS |
1078 | ssize_t res; |
1079 | struct inode *inode = file->f_path.dentry->d_inode; | |
1080 | ||
1081 | if (is_bad_inode(inode)) | |
1082 | return -EIO; | |
1083 | ||
1084 | res = fuse_direct_io(file, buf, count, ppos, 0); | |
1085 | ||
1086 | fuse_invalidate_attr(inode); | |
1087 | ||
1088 | return res; | |
413ef8cb MS |
1089 | } |
1090 | ||
1091 | static ssize_t fuse_direct_write(struct file *file, const char __user *buf, | |
1092 | size_t count, loff_t *ppos) | |
1093 | { | |
7706a9d6 | 1094 | struct inode *inode = file->f_path.dentry->d_inode; |
413ef8cb | 1095 | ssize_t res; |
d09cb9d7 MS |
1096 | |
1097 | if (is_bad_inode(inode)) | |
1098 | return -EIO; | |
1099 | ||
413ef8cb | 1100 | /* Don't allow parallel writes to the same file */ |
1b1dcc1b | 1101 | mutex_lock(&inode->i_mutex); |
889f7848 | 1102 | res = generic_write_checks(file, ppos, &count, 0); |
d09cb9d7 | 1103 | if (!res) { |
889f7848 | 1104 | res = fuse_direct_io(file, buf, count, ppos, 1); |
d09cb9d7 MS |
1105 | if (res > 0) |
1106 | fuse_write_update_size(inode, *ppos); | |
1107 | } | |
1b1dcc1b | 1108 | mutex_unlock(&inode->i_mutex); |
d09cb9d7 MS |
1109 | |
1110 | fuse_invalidate_attr(inode); | |
1111 | ||
413ef8cb MS |
1112 | return res; |
1113 | } | |
1114 | ||
3be5a52b | 1115 | static void fuse_writepage_free(struct fuse_conn *fc, struct fuse_req *req) |
b6aeaded | 1116 | { |
3be5a52b MS |
1117 | __free_page(req->pages[0]); |
1118 | fuse_file_put(req->ff); | |
3be5a52b MS |
1119 | } |
1120 | ||
1121 | static void fuse_writepage_finish(struct fuse_conn *fc, struct fuse_req *req) | |
1122 | { | |
1123 | struct inode *inode = req->inode; | |
1124 | struct fuse_inode *fi = get_fuse_inode(inode); | |
1125 | struct backing_dev_info *bdi = inode->i_mapping->backing_dev_info; | |
1126 | ||
1127 | list_del(&req->writepages_entry); | |
1128 | dec_bdi_stat(bdi, BDI_WRITEBACK); | |
1129 | dec_zone_page_state(req->pages[0], NR_WRITEBACK_TEMP); | |
1130 | bdi_writeout_inc(bdi); | |
1131 | wake_up(&fi->page_waitq); | |
1132 | } | |
1133 | ||
1134 | /* Called under fc->lock, may release and reacquire it */ | |
1135 | static void fuse_send_writepage(struct fuse_conn *fc, struct fuse_req *req) | |
5d9ec854 HH |
1136 | __releases(&fc->lock) |
1137 | __acquires(&fc->lock) | |
3be5a52b MS |
1138 | { |
1139 | struct fuse_inode *fi = get_fuse_inode(req->inode); | |
1140 | loff_t size = i_size_read(req->inode); | |
1141 | struct fuse_write_in *inarg = &req->misc.write.in; | |
1142 | ||
1143 | if (!fc->connected) | |
1144 | goto out_free; | |
1145 | ||
1146 | if (inarg->offset + PAGE_CACHE_SIZE <= size) { | |
1147 | inarg->size = PAGE_CACHE_SIZE; | |
1148 | } else if (inarg->offset < size) { | |
1149 | inarg->size = size & (PAGE_CACHE_SIZE - 1); | |
1150 | } else { | |
1151 | /* Got truncated off completely */ | |
1152 | goto out_free; | |
b6aeaded | 1153 | } |
3be5a52b MS |
1154 | |
1155 | req->in.args[1].size = inarg->size; | |
1156 | fi->writectr++; | |
b93f858a | 1157 | fuse_request_send_background_locked(fc, req); |
3be5a52b MS |
1158 | return; |
1159 | ||
1160 | out_free: | |
1161 | fuse_writepage_finish(fc, req); | |
1162 | spin_unlock(&fc->lock); | |
1163 | fuse_writepage_free(fc, req); | |
e9bb09dd | 1164 | fuse_put_request(fc, req); |
3be5a52b | 1165 | spin_lock(&fc->lock); |
b6aeaded MS |
1166 | } |
1167 | ||
3be5a52b MS |
1168 | /* |
1169 | * If fi->writectr is positive (no truncate or fsync going on) send | |
1170 | * all queued writepage requests. | |
1171 | * | |
1172 | * Called with fc->lock | |
1173 | */ | |
1174 | void fuse_flush_writepages(struct inode *inode) | |
5d9ec854 HH |
1175 | __releases(&fc->lock) |
1176 | __acquires(&fc->lock) | |
b6aeaded | 1177 | { |
3be5a52b MS |
1178 | struct fuse_conn *fc = get_fuse_conn(inode); |
1179 | struct fuse_inode *fi = get_fuse_inode(inode); | |
1180 | struct fuse_req *req; | |
1181 | ||
1182 | while (fi->writectr >= 0 && !list_empty(&fi->queued_writes)) { | |
1183 | req = list_entry(fi->queued_writes.next, struct fuse_req, list); | |
1184 | list_del_init(&req->list); | |
1185 | fuse_send_writepage(fc, req); | |
1186 | } | |
1187 | } | |
1188 | ||
1189 | static void fuse_writepage_end(struct fuse_conn *fc, struct fuse_req *req) | |
1190 | { | |
1191 | struct inode *inode = req->inode; | |
1192 | struct fuse_inode *fi = get_fuse_inode(inode); | |
1193 | ||
1194 | mapping_set_error(inode->i_mapping, req->out.h.error); | |
1195 | spin_lock(&fc->lock); | |
1196 | fi->writectr--; | |
1197 | fuse_writepage_finish(fc, req); | |
1198 | spin_unlock(&fc->lock); | |
1199 | fuse_writepage_free(fc, req); | |
1200 | } | |
1201 | ||
1202 | static int fuse_writepage_locked(struct page *page) | |
1203 | { | |
1204 | struct address_space *mapping = page->mapping; | |
1205 | struct inode *inode = mapping->host; | |
1206 | struct fuse_conn *fc = get_fuse_conn(inode); | |
1207 | struct fuse_inode *fi = get_fuse_inode(inode); | |
1208 | struct fuse_req *req; | |
1209 | struct fuse_file *ff; | |
1210 | struct page *tmp_page; | |
1211 | ||
1212 | set_page_writeback(page); | |
1213 | ||
1214 | req = fuse_request_alloc_nofs(); | |
1215 | if (!req) | |
1216 | goto err; | |
1217 | ||
1218 | tmp_page = alloc_page(GFP_NOFS | __GFP_HIGHMEM); | |
1219 | if (!tmp_page) | |
1220 | goto err_free; | |
1221 | ||
1222 | spin_lock(&fc->lock); | |
1223 | BUG_ON(list_empty(&fi->write_files)); | |
1224 | ff = list_entry(fi->write_files.next, struct fuse_file, write_entry); | |
1225 | req->ff = fuse_file_get(ff); | |
1226 | spin_unlock(&fc->lock); | |
1227 | ||
2106cb18 | 1228 | fuse_write_fill(req, ff, page_offset(page), 0); |
3be5a52b MS |
1229 | |
1230 | copy_highpage(tmp_page, page); | |
2d698b07 | 1231 | req->misc.write.in.write_flags |= FUSE_WRITE_CACHE; |
f4975c67 | 1232 | req->in.argpages = 1; |
3be5a52b MS |
1233 | req->num_pages = 1; |
1234 | req->pages[0] = tmp_page; | |
1235 | req->page_offset = 0; | |
1236 | req->end = fuse_writepage_end; | |
1237 | req->inode = inode; | |
1238 | ||
1239 | inc_bdi_stat(mapping->backing_dev_info, BDI_WRITEBACK); | |
1240 | inc_zone_page_state(tmp_page, NR_WRITEBACK_TEMP); | |
1241 | end_page_writeback(page); | |
1242 | ||
1243 | spin_lock(&fc->lock); | |
1244 | list_add(&req->writepages_entry, &fi->writepages); | |
1245 | list_add_tail(&req->list, &fi->queued_writes); | |
1246 | fuse_flush_writepages(inode); | |
1247 | spin_unlock(&fc->lock); | |
1248 | ||
1249 | return 0; | |
1250 | ||
1251 | err_free: | |
1252 | fuse_request_free(req); | |
1253 | err: | |
1254 | end_page_writeback(page); | |
1255 | return -ENOMEM; | |
1256 | } | |
1257 | ||
1258 | static int fuse_writepage(struct page *page, struct writeback_control *wbc) | |
1259 | { | |
1260 | int err; | |
1261 | ||
1262 | err = fuse_writepage_locked(page); | |
1263 | unlock_page(page); | |
1264 | ||
1265 | return err; | |
1266 | } | |
1267 | ||
1268 | static int fuse_launder_page(struct page *page) | |
1269 | { | |
1270 | int err = 0; | |
1271 | if (clear_page_dirty_for_io(page)) { | |
1272 | struct inode *inode = page->mapping->host; | |
1273 | err = fuse_writepage_locked(page); | |
1274 | if (!err) | |
1275 | fuse_wait_on_page_writeback(inode, page->index); | |
1276 | } | |
1277 | return err; | |
1278 | } | |
1279 | ||
1280 | /* | |
1281 | * Write back dirty pages now, because there may not be any suitable | |
1282 | * open files later | |
1283 | */ | |
1284 | static void fuse_vma_close(struct vm_area_struct *vma) | |
1285 | { | |
1286 | filemap_write_and_wait(vma->vm_file->f_mapping); | |
1287 | } | |
1288 | ||
1289 | /* | |
1290 | * Wait for writeback against this page to complete before allowing it | |
1291 | * to be marked dirty again, and hence written back again, possibly | |
1292 | * before the previous writepage completed. | |
1293 | * | |
1294 | * Block here, instead of in ->writepage(), so that the userspace fs | |
1295 | * can only block processes actually operating on the filesystem. | |
1296 | * | |
1297 | * Otherwise unprivileged userspace fs would be able to block | |
1298 | * unrelated: | |
1299 | * | |
1300 | * - page migration | |
1301 | * - sync(2) | |
1302 | * - try_to_free_pages() with order > PAGE_ALLOC_COSTLY_ORDER | |
1303 | */ | |
c2ec175c | 1304 | static int fuse_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) |
3be5a52b | 1305 | { |
c2ec175c | 1306 | struct page *page = vmf->page; |
3be5a52b MS |
1307 | /* |
1308 | * Don't use page->mapping as it may become NULL from a | |
1309 | * concurrent truncate. | |
1310 | */ | |
1311 | struct inode *inode = vma->vm_file->f_mapping->host; | |
1312 | ||
1313 | fuse_wait_on_page_writeback(inode, page->index); | |
1314 | return 0; | |
1315 | } | |
1316 | ||
f0f37e2f | 1317 | static const struct vm_operations_struct fuse_file_vm_ops = { |
3be5a52b MS |
1318 | .close = fuse_vma_close, |
1319 | .fault = filemap_fault, | |
1320 | .page_mkwrite = fuse_page_mkwrite, | |
1321 | }; | |
1322 | ||
1323 | static int fuse_file_mmap(struct file *file, struct vm_area_struct *vma) | |
1324 | { | |
1325 | if ((vma->vm_flags & VM_SHARED) && (vma->vm_flags & VM_MAYWRITE)) { | |
1326 | struct inode *inode = file->f_dentry->d_inode; | |
1327 | struct fuse_conn *fc = get_fuse_conn(inode); | |
1328 | struct fuse_inode *fi = get_fuse_inode(inode); | |
1329 | struct fuse_file *ff = file->private_data; | |
1330 | /* | |
1331 | * file may be written through mmap, so chain it onto the | |
1332 | * inodes's write_file list | |
1333 | */ | |
1334 | spin_lock(&fc->lock); | |
1335 | if (list_empty(&ff->write_entry)) | |
1336 | list_add(&ff->write_entry, &fi->write_files); | |
1337 | spin_unlock(&fc->lock); | |
1338 | } | |
1339 | file_accessed(file); | |
1340 | vma->vm_ops = &fuse_file_vm_ops; | |
b6aeaded MS |
1341 | return 0; |
1342 | } | |
1343 | ||
fc280c96 MS |
1344 | static int fuse_direct_mmap(struct file *file, struct vm_area_struct *vma) |
1345 | { | |
1346 | /* Can't provide the coherency needed for MAP_SHARED */ | |
1347 | if (vma->vm_flags & VM_MAYSHARE) | |
1348 | return -ENODEV; | |
1349 | ||
3121bfe7 MS |
1350 | invalidate_inode_pages2(file->f_mapping); |
1351 | ||
fc280c96 MS |
1352 | return generic_file_mmap(file, vma); |
1353 | } | |
1354 | ||
71421259 MS |
1355 | static int convert_fuse_file_lock(const struct fuse_file_lock *ffl, |
1356 | struct file_lock *fl) | |
1357 | { | |
1358 | switch (ffl->type) { | |
1359 | case F_UNLCK: | |
1360 | break; | |
1361 | ||
1362 | case F_RDLCK: | |
1363 | case F_WRLCK: | |
1364 | if (ffl->start > OFFSET_MAX || ffl->end > OFFSET_MAX || | |
1365 | ffl->end < ffl->start) | |
1366 | return -EIO; | |
1367 | ||
1368 | fl->fl_start = ffl->start; | |
1369 | fl->fl_end = ffl->end; | |
1370 | fl->fl_pid = ffl->pid; | |
1371 | break; | |
1372 | ||
1373 | default: | |
1374 | return -EIO; | |
1375 | } | |
1376 | fl->fl_type = ffl->type; | |
1377 | return 0; | |
1378 | } | |
1379 | ||
1380 | static void fuse_lk_fill(struct fuse_req *req, struct file *file, | |
a9ff4f87 MS |
1381 | const struct file_lock *fl, int opcode, pid_t pid, |
1382 | int flock) | |
71421259 | 1383 | { |
7706a9d6 | 1384 | struct inode *inode = file->f_path.dentry->d_inode; |
9c8ef561 | 1385 | struct fuse_conn *fc = get_fuse_conn(inode); |
71421259 MS |
1386 | struct fuse_file *ff = file->private_data; |
1387 | struct fuse_lk_in *arg = &req->misc.lk_in; | |
1388 | ||
1389 | arg->fh = ff->fh; | |
9c8ef561 | 1390 | arg->owner = fuse_lock_owner_id(fc, fl->fl_owner); |
71421259 MS |
1391 | arg->lk.start = fl->fl_start; |
1392 | arg->lk.end = fl->fl_end; | |
1393 | arg->lk.type = fl->fl_type; | |
1394 | arg->lk.pid = pid; | |
a9ff4f87 MS |
1395 | if (flock) |
1396 | arg->lk_flags |= FUSE_LK_FLOCK; | |
71421259 MS |
1397 | req->in.h.opcode = opcode; |
1398 | req->in.h.nodeid = get_node_id(inode); | |
1399 | req->in.numargs = 1; | |
1400 | req->in.args[0].size = sizeof(*arg); | |
1401 | req->in.args[0].value = arg; | |
1402 | } | |
1403 | ||
1404 | static int fuse_getlk(struct file *file, struct file_lock *fl) | |
1405 | { | |
7706a9d6 | 1406 | struct inode *inode = file->f_path.dentry->d_inode; |
71421259 MS |
1407 | struct fuse_conn *fc = get_fuse_conn(inode); |
1408 | struct fuse_req *req; | |
1409 | struct fuse_lk_out outarg; | |
1410 | int err; | |
1411 | ||
1412 | req = fuse_get_req(fc); | |
1413 | if (IS_ERR(req)) | |
1414 | return PTR_ERR(req); | |
1415 | ||
a9ff4f87 | 1416 | fuse_lk_fill(req, file, fl, FUSE_GETLK, 0, 0); |
71421259 MS |
1417 | req->out.numargs = 1; |
1418 | req->out.args[0].size = sizeof(outarg); | |
1419 | req->out.args[0].value = &outarg; | |
b93f858a | 1420 | fuse_request_send(fc, req); |
71421259 MS |
1421 | err = req->out.h.error; |
1422 | fuse_put_request(fc, req); | |
1423 | if (!err) | |
1424 | err = convert_fuse_file_lock(&outarg.lk, fl); | |
1425 | ||
1426 | return err; | |
1427 | } | |
1428 | ||
a9ff4f87 | 1429 | static int fuse_setlk(struct file *file, struct file_lock *fl, int flock) |
71421259 | 1430 | { |
7706a9d6 | 1431 | struct inode *inode = file->f_path.dentry->d_inode; |
71421259 MS |
1432 | struct fuse_conn *fc = get_fuse_conn(inode); |
1433 | struct fuse_req *req; | |
1434 | int opcode = (fl->fl_flags & FL_SLEEP) ? FUSE_SETLKW : FUSE_SETLK; | |
1435 | pid_t pid = fl->fl_type != F_UNLCK ? current->tgid : 0; | |
1436 | int err; | |
1437 | ||
48e90761 MS |
1438 | if (fl->fl_lmops && fl->fl_lmops->fl_grant) { |
1439 | /* NLM needs asynchronous locks, which we don't support yet */ | |
1440 | return -ENOLCK; | |
1441 | } | |
1442 | ||
71421259 MS |
1443 | /* Unlock on close is handled by the flush method */ |
1444 | if (fl->fl_flags & FL_CLOSE) | |
1445 | return 0; | |
1446 | ||
1447 | req = fuse_get_req(fc); | |
1448 | if (IS_ERR(req)) | |
1449 | return PTR_ERR(req); | |
1450 | ||
a9ff4f87 | 1451 | fuse_lk_fill(req, file, fl, opcode, pid, flock); |
b93f858a | 1452 | fuse_request_send(fc, req); |
71421259 | 1453 | err = req->out.h.error; |
a4d27e75 MS |
1454 | /* locking is restartable */ |
1455 | if (err == -EINTR) | |
1456 | err = -ERESTARTSYS; | |
71421259 MS |
1457 | fuse_put_request(fc, req); |
1458 | return err; | |
1459 | } | |
1460 | ||
1461 | static int fuse_file_lock(struct file *file, int cmd, struct file_lock *fl) | |
1462 | { | |
7706a9d6 | 1463 | struct inode *inode = file->f_path.dentry->d_inode; |
71421259 MS |
1464 | struct fuse_conn *fc = get_fuse_conn(inode); |
1465 | int err; | |
1466 | ||
48e90761 MS |
1467 | if (cmd == F_CANCELLK) { |
1468 | err = 0; | |
1469 | } else if (cmd == F_GETLK) { | |
71421259 | 1470 | if (fc->no_lock) { |
9d6a8c5c | 1471 | posix_test_lock(file, fl); |
71421259 MS |
1472 | err = 0; |
1473 | } else | |
1474 | err = fuse_getlk(file, fl); | |
1475 | } else { | |
1476 | if (fc->no_lock) | |
48e90761 | 1477 | err = posix_lock_file(file, fl, NULL); |
71421259 | 1478 | else |
a9ff4f87 | 1479 | err = fuse_setlk(file, fl, 0); |
71421259 MS |
1480 | } |
1481 | return err; | |
1482 | } | |
1483 | ||
a9ff4f87 MS |
1484 | static int fuse_file_flock(struct file *file, int cmd, struct file_lock *fl) |
1485 | { | |
1486 | struct inode *inode = file->f_path.dentry->d_inode; | |
1487 | struct fuse_conn *fc = get_fuse_conn(inode); | |
1488 | int err; | |
1489 | ||
1490 | if (fc->no_lock) { | |
1491 | err = flock_lock_file_wait(file, fl); | |
1492 | } else { | |
1493 | /* emulate flock with POSIX locks */ | |
1494 | fl->fl_owner = (fl_owner_t) file; | |
1495 | err = fuse_setlk(file, fl, 1); | |
1496 | } | |
1497 | ||
1498 | return err; | |
1499 | } | |
1500 | ||
b2d2272f MS |
1501 | static sector_t fuse_bmap(struct address_space *mapping, sector_t block) |
1502 | { | |
1503 | struct inode *inode = mapping->host; | |
1504 | struct fuse_conn *fc = get_fuse_conn(inode); | |
1505 | struct fuse_req *req; | |
1506 | struct fuse_bmap_in inarg; | |
1507 | struct fuse_bmap_out outarg; | |
1508 | int err; | |
1509 | ||
1510 | if (!inode->i_sb->s_bdev || fc->no_bmap) | |
1511 | return 0; | |
1512 | ||
1513 | req = fuse_get_req(fc); | |
1514 | if (IS_ERR(req)) | |
1515 | return 0; | |
1516 | ||
1517 | memset(&inarg, 0, sizeof(inarg)); | |
1518 | inarg.block = block; | |
1519 | inarg.blocksize = inode->i_sb->s_blocksize; | |
1520 | req->in.h.opcode = FUSE_BMAP; | |
1521 | req->in.h.nodeid = get_node_id(inode); | |
1522 | req->in.numargs = 1; | |
1523 | req->in.args[0].size = sizeof(inarg); | |
1524 | req->in.args[0].value = &inarg; | |
1525 | req->out.numargs = 1; | |
1526 | req->out.args[0].size = sizeof(outarg); | |
1527 | req->out.args[0].value = &outarg; | |
b93f858a | 1528 | fuse_request_send(fc, req); |
b2d2272f MS |
1529 | err = req->out.h.error; |
1530 | fuse_put_request(fc, req); | |
1531 | if (err == -ENOSYS) | |
1532 | fc->no_bmap = 1; | |
1533 | ||
1534 | return err ? 0 : outarg.block; | |
1535 | } | |
1536 | ||
5559b8f4 MS |
1537 | static loff_t fuse_file_llseek(struct file *file, loff_t offset, int origin) |
1538 | { | |
1539 | loff_t retval; | |
1540 | struct inode *inode = file->f_path.dentry->d_inode; | |
1541 | ||
1542 | mutex_lock(&inode->i_mutex); | |
1543 | switch (origin) { | |
1544 | case SEEK_END: | |
769415c6 MS |
1545 | retval = fuse_update_attributes(inode, NULL, file, NULL); |
1546 | if (retval) | |
5291658d | 1547 | goto exit; |
5559b8f4 MS |
1548 | offset += i_size_read(inode); |
1549 | break; | |
1550 | case SEEK_CUR: | |
1551 | offset += file->f_pos; | |
1552 | } | |
1553 | retval = -EINVAL; | |
1554 | if (offset >= 0 && offset <= inode->i_sb->s_maxbytes) { | |
1555 | if (offset != file->f_pos) { | |
1556 | file->f_pos = offset; | |
1557 | file->f_version = 0; | |
1558 | } | |
1559 | retval = offset; | |
1560 | } | |
5291658d | 1561 | exit: |
5559b8f4 MS |
1562 | mutex_unlock(&inode->i_mutex); |
1563 | return retval; | |
1564 | } | |
1565 | ||
59efec7b TH |
1566 | static int fuse_ioctl_copy_user(struct page **pages, struct iovec *iov, |
1567 | unsigned int nr_segs, size_t bytes, bool to_user) | |
1568 | { | |
1569 | struct iov_iter ii; | |
1570 | int page_idx = 0; | |
1571 | ||
1572 | if (!bytes) | |
1573 | return 0; | |
1574 | ||
1575 | iov_iter_init(&ii, iov, nr_segs, bytes, 0); | |
1576 | ||
1577 | while (iov_iter_count(&ii)) { | |
1578 | struct page *page = pages[page_idx++]; | |
1579 | size_t todo = min_t(size_t, PAGE_SIZE, iov_iter_count(&ii)); | |
1580 | void *kaddr, *map; | |
1581 | ||
1582 | kaddr = map = kmap(page); | |
1583 | ||
1584 | while (todo) { | |
1585 | char __user *uaddr = ii.iov->iov_base + ii.iov_offset; | |
1586 | size_t iov_len = ii.iov->iov_len - ii.iov_offset; | |
1587 | size_t copy = min(todo, iov_len); | |
1588 | size_t left; | |
1589 | ||
1590 | if (!to_user) | |
1591 | left = copy_from_user(kaddr, uaddr, copy); | |
1592 | else | |
1593 | left = copy_to_user(uaddr, kaddr, copy); | |
1594 | ||
1595 | if (unlikely(left)) | |
1596 | return -EFAULT; | |
1597 | ||
1598 | iov_iter_advance(&ii, copy); | |
1599 | todo -= copy; | |
1600 | kaddr += copy; | |
1601 | } | |
1602 | ||
0bd87182 | 1603 | kunmap(page); |
59efec7b TH |
1604 | } |
1605 | ||
1606 | return 0; | |
1607 | } | |
1608 | ||
1609 | /* | |
1610 | * For ioctls, there is no generic way to determine how much memory | |
1611 | * needs to be read and/or written. Furthermore, ioctls are allowed | |
1612 | * to dereference the passed pointer, so the parameter requires deep | |
1613 | * copying but FUSE has no idea whatsoever about what to copy in or | |
1614 | * out. | |
1615 | * | |
1616 | * This is solved by allowing FUSE server to retry ioctl with | |
1617 | * necessary in/out iovecs. Let's assume the ioctl implementation | |
1618 | * needs to read in the following structure. | |
1619 | * | |
1620 | * struct a { | |
1621 | * char *buf; | |
1622 | * size_t buflen; | |
1623 | * } | |
1624 | * | |
1625 | * On the first callout to FUSE server, inarg->in_size and | |
1626 | * inarg->out_size will be NULL; then, the server completes the ioctl | |
1627 | * with FUSE_IOCTL_RETRY set in out->flags, out->in_iovs set to 1 and | |
1628 | * the actual iov array to | |
1629 | * | |
1630 | * { { .iov_base = inarg.arg, .iov_len = sizeof(struct a) } } | |
1631 | * | |
1632 | * which tells FUSE to copy in the requested area and retry the ioctl. | |
1633 | * On the second round, the server has access to the structure and | |
1634 | * from that it can tell what to look for next, so on the invocation, | |
1635 | * it sets FUSE_IOCTL_RETRY, out->in_iovs to 2 and iov array to | |
1636 | * | |
1637 | * { { .iov_base = inarg.arg, .iov_len = sizeof(struct a) }, | |
1638 | * { .iov_base = a.buf, .iov_len = a.buflen } } | |
1639 | * | |
1640 | * FUSE will copy both struct a and the pointed buffer from the | |
1641 | * process doing the ioctl and retry ioctl with both struct a and the | |
1642 | * buffer. | |
1643 | * | |
1644 | * This time, FUSE server has everything it needs and completes ioctl | |
1645 | * without FUSE_IOCTL_RETRY which finishes the ioctl call. | |
1646 | * | |
1647 | * Copying data out works the same way. | |
1648 | * | |
1649 | * Note that if FUSE_IOCTL_UNRESTRICTED is clear, the kernel | |
1650 | * automatically initializes in and out iovs by decoding @cmd with | |
1651 | * _IOC_* macros and the server is not allowed to request RETRY. This | |
1652 | * limits ioctl data transfers to well-formed ioctls and is the forced | |
1653 | * behavior for all FUSE servers. | |
1654 | */ | |
08cbf542 TH |
1655 | long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg, |
1656 | unsigned int flags) | |
59efec7b | 1657 | { |
59efec7b | 1658 | struct fuse_file *ff = file->private_data; |
d36f2487 | 1659 | struct fuse_conn *fc = ff->fc; |
59efec7b TH |
1660 | struct fuse_ioctl_in inarg = { |
1661 | .fh = ff->fh, | |
1662 | .cmd = cmd, | |
1663 | .arg = arg, | |
1664 | .flags = flags | |
1665 | }; | |
1666 | struct fuse_ioctl_out outarg; | |
1667 | struct fuse_req *req = NULL; | |
1668 | struct page **pages = NULL; | |
1669 | struct page *iov_page = NULL; | |
1670 | struct iovec *in_iov = NULL, *out_iov = NULL; | |
1671 | unsigned int in_iovs = 0, out_iovs = 0, num_pages = 0, max_pages; | |
1672 | size_t in_size, out_size, transferred; | |
1673 | int err; | |
1674 | ||
1675 | /* assume all the iovs returned by client always fits in a page */ | |
1676 | BUILD_BUG_ON(sizeof(struct iovec) * FUSE_IOCTL_MAX_IOV > PAGE_SIZE); | |
1677 | ||
59efec7b TH |
1678 | err = -ENOMEM; |
1679 | pages = kzalloc(sizeof(pages[0]) * FUSE_MAX_PAGES_PER_REQ, GFP_KERNEL); | |
1680 | iov_page = alloc_page(GFP_KERNEL); | |
1681 | if (!pages || !iov_page) | |
1682 | goto out; | |
1683 | ||
1684 | /* | |
1685 | * If restricted, initialize IO parameters as encoded in @cmd. | |
1686 | * RETRY from server is not allowed. | |
1687 | */ | |
1688 | if (!(flags & FUSE_IOCTL_UNRESTRICTED)) { | |
1689 | struct iovec *iov = page_address(iov_page); | |
1690 | ||
c9f0523d | 1691 | iov->iov_base = (void __user *)arg; |
59efec7b TH |
1692 | iov->iov_len = _IOC_SIZE(cmd); |
1693 | ||
1694 | if (_IOC_DIR(cmd) & _IOC_WRITE) { | |
1695 | in_iov = iov; | |
1696 | in_iovs = 1; | |
1697 | } | |
1698 | ||
1699 | if (_IOC_DIR(cmd) & _IOC_READ) { | |
1700 | out_iov = iov; | |
1701 | out_iovs = 1; | |
1702 | } | |
1703 | } | |
1704 | ||
1705 | retry: | |
1706 | inarg.in_size = in_size = iov_length(in_iov, in_iovs); | |
1707 | inarg.out_size = out_size = iov_length(out_iov, out_iovs); | |
1708 | ||
1709 | /* | |
1710 | * Out data can be used either for actual out data or iovs, | |
1711 | * make sure there always is at least one page. | |
1712 | */ | |
1713 | out_size = max_t(size_t, out_size, PAGE_SIZE); | |
1714 | max_pages = DIV_ROUND_UP(max(in_size, out_size), PAGE_SIZE); | |
1715 | ||
1716 | /* make sure there are enough buffer pages and init request with them */ | |
1717 | err = -ENOMEM; | |
1718 | if (max_pages > FUSE_MAX_PAGES_PER_REQ) | |
1719 | goto out; | |
1720 | while (num_pages < max_pages) { | |
1721 | pages[num_pages] = alloc_page(GFP_KERNEL | __GFP_HIGHMEM); | |
1722 | if (!pages[num_pages]) | |
1723 | goto out; | |
1724 | num_pages++; | |
1725 | } | |
1726 | ||
1727 | req = fuse_get_req(fc); | |
1728 | if (IS_ERR(req)) { | |
1729 | err = PTR_ERR(req); | |
1730 | req = NULL; | |
1731 | goto out; | |
1732 | } | |
1733 | memcpy(req->pages, pages, sizeof(req->pages[0]) * num_pages); | |
1734 | req->num_pages = num_pages; | |
1735 | ||
1736 | /* okay, let's send it to the client */ | |
1737 | req->in.h.opcode = FUSE_IOCTL; | |
d36f2487 | 1738 | req->in.h.nodeid = ff->nodeid; |
59efec7b TH |
1739 | req->in.numargs = 1; |
1740 | req->in.args[0].size = sizeof(inarg); | |
1741 | req->in.args[0].value = &inarg; | |
1742 | if (in_size) { | |
1743 | req->in.numargs++; | |
1744 | req->in.args[1].size = in_size; | |
1745 | req->in.argpages = 1; | |
1746 | ||
1747 | err = fuse_ioctl_copy_user(pages, in_iov, in_iovs, in_size, | |
1748 | false); | |
1749 | if (err) | |
1750 | goto out; | |
1751 | } | |
1752 | ||
1753 | req->out.numargs = 2; | |
1754 | req->out.args[0].size = sizeof(outarg); | |
1755 | req->out.args[0].value = &outarg; | |
1756 | req->out.args[1].size = out_size; | |
1757 | req->out.argpages = 1; | |
1758 | req->out.argvar = 1; | |
1759 | ||
b93f858a | 1760 | fuse_request_send(fc, req); |
59efec7b TH |
1761 | err = req->out.h.error; |
1762 | transferred = req->out.args[1].size; | |
1763 | fuse_put_request(fc, req); | |
1764 | req = NULL; | |
1765 | if (err) | |
1766 | goto out; | |
1767 | ||
1768 | /* did it ask for retry? */ | |
1769 | if (outarg.flags & FUSE_IOCTL_RETRY) { | |
1770 | char *vaddr; | |
1771 | ||
1772 | /* no retry if in restricted mode */ | |
1773 | err = -EIO; | |
1774 | if (!(flags & FUSE_IOCTL_UNRESTRICTED)) | |
1775 | goto out; | |
1776 | ||
1777 | in_iovs = outarg.in_iovs; | |
1778 | out_iovs = outarg.out_iovs; | |
1779 | ||
1780 | /* | |
1781 | * Make sure things are in boundary, separate checks | |
1782 | * are to protect against overflow. | |
1783 | */ | |
1784 | err = -ENOMEM; | |
1785 | if (in_iovs > FUSE_IOCTL_MAX_IOV || | |
1786 | out_iovs > FUSE_IOCTL_MAX_IOV || | |
1787 | in_iovs + out_iovs > FUSE_IOCTL_MAX_IOV) | |
1788 | goto out; | |
1789 | ||
1790 | err = -EIO; | |
1791 | if ((in_iovs + out_iovs) * sizeof(struct iovec) != transferred) | |
1792 | goto out; | |
1793 | ||
1794 | /* okay, copy in iovs and retry */ | |
1795 | vaddr = kmap_atomic(pages[0], KM_USER0); | |
1796 | memcpy(page_address(iov_page), vaddr, transferred); | |
1797 | kunmap_atomic(vaddr, KM_USER0); | |
1798 | ||
1799 | in_iov = page_address(iov_page); | |
1800 | out_iov = in_iov + in_iovs; | |
1801 | ||
1802 | goto retry; | |
1803 | } | |
1804 | ||
1805 | err = -EIO; | |
1806 | if (transferred > inarg.out_size) | |
1807 | goto out; | |
1808 | ||
1809 | err = fuse_ioctl_copy_user(pages, out_iov, out_iovs, transferred, true); | |
1810 | out: | |
1811 | if (req) | |
1812 | fuse_put_request(fc, req); | |
1813 | if (iov_page) | |
1814 | __free_page(iov_page); | |
1815 | while (num_pages) | |
1816 | __free_page(pages[--num_pages]); | |
1817 | kfree(pages); | |
1818 | ||
1819 | return err ? err : outarg.result; | |
1820 | } | |
08cbf542 | 1821 | EXPORT_SYMBOL_GPL(fuse_do_ioctl); |
59efec7b | 1822 | |
d36f2487 MS |
1823 | static long fuse_file_ioctl_common(struct file *file, unsigned int cmd, |
1824 | unsigned long arg, unsigned int flags) | |
1825 | { | |
1826 | struct inode *inode = file->f_dentry->d_inode; | |
1827 | struct fuse_conn *fc = get_fuse_conn(inode); | |
1828 | ||
1829 | if (!fuse_allow_task(fc, current)) | |
1830 | return -EACCES; | |
1831 | ||
1832 | if (is_bad_inode(inode)) | |
1833 | return -EIO; | |
1834 | ||
1835 | return fuse_do_ioctl(file, cmd, arg, flags); | |
1836 | } | |
1837 | ||
59efec7b TH |
1838 | static long fuse_file_ioctl(struct file *file, unsigned int cmd, |
1839 | unsigned long arg) | |
1840 | { | |
d36f2487 | 1841 | return fuse_file_ioctl_common(file, cmd, arg, 0); |
59efec7b TH |
1842 | } |
1843 | ||
1844 | static long fuse_file_compat_ioctl(struct file *file, unsigned int cmd, | |
1845 | unsigned long arg) | |
1846 | { | |
d36f2487 | 1847 | return fuse_file_ioctl_common(file, cmd, arg, FUSE_IOCTL_COMPAT); |
59efec7b TH |
1848 | } |
1849 | ||
95668a69 TH |
1850 | /* |
1851 | * All files which have been polled are linked to RB tree | |
1852 | * fuse_conn->polled_files which is indexed by kh. Walk the tree and | |
1853 | * find the matching one. | |
1854 | */ | |
1855 | static struct rb_node **fuse_find_polled_node(struct fuse_conn *fc, u64 kh, | |
1856 | struct rb_node **parent_out) | |
1857 | { | |
1858 | struct rb_node **link = &fc->polled_files.rb_node; | |
1859 | struct rb_node *last = NULL; | |
1860 | ||
1861 | while (*link) { | |
1862 | struct fuse_file *ff; | |
1863 | ||
1864 | last = *link; | |
1865 | ff = rb_entry(last, struct fuse_file, polled_node); | |
1866 | ||
1867 | if (kh < ff->kh) | |
1868 | link = &last->rb_left; | |
1869 | else if (kh > ff->kh) | |
1870 | link = &last->rb_right; | |
1871 | else | |
1872 | return link; | |
1873 | } | |
1874 | ||
1875 | if (parent_out) | |
1876 | *parent_out = last; | |
1877 | return link; | |
1878 | } | |
1879 | ||
1880 | /* | |
1881 | * The file is about to be polled. Make sure it's on the polled_files | |
1882 | * RB tree. Note that files once added to the polled_files tree are | |
1883 | * not removed before the file is released. This is because a file | |
1884 | * polled once is likely to be polled again. | |
1885 | */ | |
1886 | static void fuse_register_polled_file(struct fuse_conn *fc, | |
1887 | struct fuse_file *ff) | |
1888 | { | |
1889 | spin_lock(&fc->lock); | |
1890 | if (RB_EMPTY_NODE(&ff->polled_node)) { | |
1891 | struct rb_node **link, *parent; | |
1892 | ||
1893 | link = fuse_find_polled_node(fc, ff->kh, &parent); | |
1894 | BUG_ON(*link); | |
1895 | rb_link_node(&ff->polled_node, parent, link); | |
1896 | rb_insert_color(&ff->polled_node, &fc->polled_files); | |
1897 | } | |
1898 | spin_unlock(&fc->lock); | |
1899 | } | |
1900 | ||
08cbf542 | 1901 | unsigned fuse_file_poll(struct file *file, poll_table *wait) |
95668a69 | 1902 | { |
95668a69 | 1903 | struct fuse_file *ff = file->private_data; |
797759aa | 1904 | struct fuse_conn *fc = ff->fc; |
95668a69 TH |
1905 | struct fuse_poll_in inarg = { .fh = ff->fh, .kh = ff->kh }; |
1906 | struct fuse_poll_out outarg; | |
1907 | struct fuse_req *req; | |
1908 | int err; | |
1909 | ||
1910 | if (fc->no_poll) | |
1911 | return DEFAULT_POLLMASK; | |
1912 | ||
1913 | poll_wait(file, &ff->poll_wait, wait); | |
1914 | ||
1915 | /* | |
1916 | * Ask for notification iff there's someone waiting for it. | |
1917 | * The client may ignore the flag and always notify. | |
1918 | */ | |
1919 | if (waitqueue_active(&ff->poll_wait)) { | |
1920 | inarg.flags |= FUSE_POLL_SCHEDULE_NOTIFY; | |
1921 | fuse_register_polled_file(fc, ff); | |
1922 | } | |
1923 | ||
1924 | req = fuse_get_req(fc); | |
1925 | if (IS_ERR(req)) | |
201fa69a | 1926 | return POLLERR; |
95668a69 TH |
1927 | |
1928 | req->in.h.opcode = FUSE_POLL; | |
797759aa | 1929 | req->in.h.nodeid = ff->nodeid; |
95668a69 TH |
1930 | req->in.numargs = 1; |
1931 | req->in.args[0].size = sizeof(inarg); | |
1932 | req->in.args[0].value = &inarg; | |
1933 | req->out.numargs = 1; | |
1934 | req->out.args[0].size = sizeof(outarg); | |
1935 | req->out.args[0].value = &outarg; | |
b93f858a | 1936 | fuse_request_send(fc, req); |
95668a69 TH |
1937 | err = req->out.h.error; |
1938 | fuse_put_request(fc, req); | |
1939 | ||
1940 | if (!err) | |
1941 | return outarg.revents; | |
1942 | if (err == -ENOSYS) { | |
1943 | fc->no_poll = 1; | |
1944 | return DEFAULT_POLLMASK; | |
1945 | } | |
1946 | return POLLERR; | |
1947 | } | |
08cbf542 | 1948 | EXPORT_SYMBOL_GPL(fuse_file_poll); |
95668a69 TH |
1949 | |
1950 | /* | |
1951 | * This is called from fuse_handle_notify() on FUSE_NOTIFY_POLL and | |
1952 | * wakes up the poll waiters. | |
1953 | */ | |
1954 | int fuse_notify_poll_wakeup(struct fuse_conn *fc, | |
1955 | struct fuse_notify_poll_wakeup_out *outarg) | |
1956 | { | |
1957 | u64 kh = outarg->kh; | |
1958 | struct rb_node **link; | |
1959 | ||
1960 | spin_lock(&fc->lock); | |
1961 | ||
1962 | link = fuse_find_polled_node(fc, kh, NULL); | |
1963 | if (*link) { | |
1964 | struct fuse_file *ff; | |
1965 | ||
1966 | ff = rb_entry(*link, struct fuse_file, polled_node); | |
1967 | wake_up_interruptible_sync(&ff->poll_wait); | |
1968 | } | |
1969 | ||
1970 | spin_unlock(&fc->lock); | |
1971 | return 0; | |
1972 | } | |
1973 | ||
4b6f5d20 | 1974 | static const struct file_operations fuse_file_operations = { |
5559b8f4 | 1975 | .llseek = fuse_file_llseek, |
543ade1f | 1976 | .read = do_sync_read, |
bcb4be80 | 1977 | .aio_read = fuse_file_aio_read, |
543ade1f | 1978 | .write = do_sync_write, |
ea9b9907 | 1979 | .aio_write = fuse_file_aio_write, |
b6aeaded MS |
1980 | .mmap = fuse_file_mmap, |
1981 | .open = fuse_open, | |
1982 | .flush = fuse_flush, | |
1983 | .release = fuse_release, | |
1984 | .fsync = fuse_fsync, | |
71421259 | 1985 | .lock = fuse_file_lock, |
a9ff4f87 | 1986 | .flock = fuse_file_flock, |
5ffc4ef4 | 1987 | .splice_read = generic_file_splice_read, |
59efec7b TH |
1988 | .unlocked_ioctl = fuse_file_ioctl, |
1989 | .compat_ioctl = fuse_file_compat_ioctl, | |
95668a69 | 1990 | .poll = fuse_file_poll, |
b6aeaded MS |
1991 | }; |
1992 | ||
4b6f5d20 | 1993 | static const struct file_operations fuse_direct_io_file_operations = { |
5559b8f4 | 1994 | .llseek = fuse_file_llseek, |
413ef8cb MS |
1995 | .read = fuse_direct_read, |
1996 | .write = fuse_direct_write, | |
fc280c96 | 1997 | .mmap = fuse_direct_mmap, |
413ef8cb MS |
1998 | .open = fuse_open, |
1999 | .flush = fuse_flush, | |
2000 | .release = fuse_release, | |
2001 | .fsync = fuse_fsync, | |
71421259 | 2002 | .lock = fuse_file_lock, |
a9ff4f87 | 2003 | .flock = fuse_file_flock, |
59efec7b TH |
2004 | .unlocked_ioctl = fuse_file_ioctl, |
2005 | .compat_ioctl = fuse_file_compat_ioctl, | |
95668a69 | 2006 | .poll = fuse_file_poll, |
fc280c96 | 2007 | /* no splice_read */ |
413ef8cb MS |
2008 | }; |
2009 | ||
f5e54d6e | 2010 | static const struct address_space_operations fuse_file_aops = { |
b6aeaded | 2011 | .readpage = fuse_readpage, |
3be5a52b MS |
2012 | .writepage = fuse_writepage, |
2013 | .launder_page = fuse_launder_page, | |
5e6f58a1 NP |
2014 | .write_begin = fuse_write_begin, |
2015 | .write_end = fuse_write_end, | |
db50b96c | 2016 | .readpages = fuse_readpages, |
3be5a52b | 2017 | .set_page_dirty = __set_page_dirty_nobuffers, |
b2d2272f | 2018 | .bmap = fuse_bmap, |
b6aeaded MS |
2019 | }; |
2020 | ||
2021 | void fuse_init_file_inode(struct inode *inode) | |
2022 | { | |
45323fb7 MS |
2023 | inode->i_fop = &fuse_file_operations; |
2024 | inode->i_data.a_ops = &fuse_file_aops; | |
b6aeaded | 2025 | } |