]>
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 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 | ||
7ea80859 | 354 | int fuse_fsync_common(struct file *file, int datasync, int isdir) |
b6aeaded | 355 | { |
7ea80859 | 356 | struct inode *inode = file->f_mapping->host; |
b6aeaded MS |
357 | struct fuse_conn *fc = get_fuse_conn(inode); |
358 | struct fuse_file *ff = file->private_data; | |
359 | struct fuse_req *req; | |
360 | struct fuse_fsync_in inarg; | |
361 | int err; | |
362 | ||
248d86e8 MS |
363 | if (is_bad_inode(inode)) |
364 | return -EIO; | |
365 | ||
82547981 | 366 | if ((!isdir && fc->no_fsync) || (isdir && fc->no_fsyncdir)) |
b6aeaded MS |
367 | return 0; |
368 | ||
3be5a52b MS |
369 | /* |
370 | * Start writeback against all dirty pages of the inode, then | |
371 | * wait for all outstanding writes, before sending the FSYNC | |
372 | * request. | |
373 | */ | |
374 | err = write_inode_now(inode, 0); | |
375 | if (err) | |
376 | return err; | |
377 | ||
378 | fuse_sync_writes(inode); | |
379 | ||
ce1d5a49 MS |
380 | req = fuse_get_req(fc); |
381 | if (IS_ERR(req)) | |
382 | return PTR_ERR(req); | |
b6aeaded MS |
383 | |
384 | memset(&inarg, 0, sizeof(inarg)); | |
385 | inarg.fh = ff->fh; | |
386 | inarg.fsync_flags = datasync ? 1 : 0; | |
82547981 | 387 | req->in.h.opcode = isdir ? FUSE_FSYNCDIR : FUSE_FSYNC; |
b6aeaded | 388 | req->in.h.nodeid = get_node_id(inode); |
b6aeaded MS |
389 | req->in.numargs = 1; |
390 | req->in.args[0].size = sizeof(inarg); | |
391 | req->in.args[0].value = &inarg; | |
b93f858a | 392 | fuse_request_send(fc, req); |
b6aeaded MS |
393 | err = req->out.h.error; |
394 | fuse_put_request(fc, req); | |
395 | if (err == -ENOSYS) { | |
82547981 MS |
396 | if (isdir) |
397 | fc->no_fsyncdir = 1; | |
398 | else | |
399 | fc->no_fsync = 1; | |
b6aeaded MS |
400 | err = 0; |
401 | } | |
402 | return err; | |
403 | } | |
404 | ||
7ea80859 | 405 | static int fuse_fsync(struct file *file, int datasync) |
82547981 | 406 | { |
7ea80859 | 407 | return fuse_fsync_common(file, datasync, 0); |
82547981 MS |
408 | } |
409 | ||
2106cb18 MS |
410 | void fuse_read_fill(struct fuse_req *req, struct file *file, loff_t pos, |
411 | size_t count, int opcode) | |
b6aeaded | 412 | { |
5c5c5e51 | 413 | struct fuse_read_in *inarg = &req->misc.read.in; |
a6643094 | 414 | struct fuse_file *ff = file->private_data; |
b6aeaded | 415 | |
361b1eb5 MS |
416 | inarg->fh = ff->fh; |
417 | inarg->offset = pos; | |
418 | inarg->size = count; | |
a6643094 | 419 | inarg->flags = file->f_flags; |
361b1eb5 | 420 | req->in.h.opcode = opcode; |
2106cb18 | 421 | req->in.h.nodeid = ff->nodeid; |
b6aeaded MS |
422 | req->in.numargs = 1; |
423 | req->in.args[0].size = sizeof(struct fuse_read_in); | |
c1aa96a5 | 424 | req->in.args[0].value = inarg; |
b6aeaded MS |
425 | req->out.argvar = 1; |
426 | req->out.numargs = 1; | |
427 | req->out.args[0].size = count; | |
b6aeaded MS |
428 | } |
429 | ||
8bfc016d | 430 | static size_t fuse_send_read(struct fuse_req *req, struct file *file, |
2106cb18 | 431 | loff_t pos, size_t count, fl_owner_t owner) |
04730fef | 432 | { |
2106cb18 MS |
433 | struct fuse_file *ff = file->private_data; |
434 | struct fuse_conn *fc = ff->fc; | |
f3332114 | 435 | |
2106cb18 | 436 | fuse_read_fill(req, file, pos, count, FUSE_READ); |
f3332114 | 437 | if (owner != NULL) { |
5c5c5e51 | 438 | struct fuse_read_in *inarg = &req->misc.read.in; |
f3332114 MS |
439 | |
440 | inarg->read_flags |= FUSE_READ_LOCKOWNER; | |
441 | inarg->lock_owner = fuse_lock_owner_id(fc, owner); | |
442 | } | |
b93f858a | 443 | fuse_request_send(fc, req); |
361b1eb5 | 444 | return req->out.args[0].size; |
04730fef MS |
445 | } |
446 | ||
5c5c5e51 MS |
447 | static void fuse_read_update_size(struct inode *inode, loff_t size, |
448 | u64 attr_ver) | |
449 | { | |
450 | struct fuse_conn *fc = get_fuse_conn(inode); | |
451 | struct fuse_inode *fi = get_fuse_inode(inode); | |
452 | ||
453 | spin_lock(&fc->lock); | |
454 | if (attr_ver == fi->attr_version && size < inode->i_size) { | |
455 | fi->attr_version = ++fc->attr_version; | |
456 | i_size_write(inode, size); | |
457 | } | |
458 | spin_unlock(&fc->lock); | |
459 | } | |
460 | ||
b6aeaded MS |
461 | static int fuse_readpage(struct file *file, struct page *page) |
462 | { | |
463 | struct inode *inode = page->mapping->host; | |
464 | struct fuse_conn *fc = get_fuse_conn(inode); | |
248d86e8 | 465 | struct fuse_req *req; |
5c5c5e51 MS |
466 | size_t num_read; |
467 | loff_t pos = page_offset(page); | |
468 | size_t count = PAGE_CACHE_SIZE; | |
469 | u64 attr_ver; | |
248d86e8 MS |
470 | int err; |
471 | ||
472 | err = -EIO; | |
473 | if (is_bad_inode(inode)) | |
474 | goto out; | |
475 | ||
3be5a52b MS |
476 | /* |
477 | * Page writeback can extend beyond the liftime of the | |
478 | * page-cache page, so make sure we read a properly synced | |
479 | * page. | |
480 | */ | |
481 | fuse_wait_on_page_writeback(inode, page->index); | |
482 | ||
ce1d5a49 MS |
483 | req = fuse_get_req(fc); |
484 | err = PTR_ERR(req); | |
485 | if (IS_ERR(req)) | |
b6aeaded MS |
486 | goto out; |
487 | ||
5c5c5e51 MS |
488 | attr_ver = fuse_get_attr_version(fc); |
489 | ||
b6aeaded | 490 | req->out.page_zeroing = 1; |
f4975c67 | 491 | req->out.argpages = 1; |
b6aeaded MS |
492 | req->num_pages = 1; |
493 | req->pages[0] = page; | |
2106cb18 | 494 | num_read = fuse_send_read(req, file, pos, count, NULL); |
b6aeaded MS |
495 | err = req->out.h.error; |
496 | fuse_put_request(fc, req); | |
5c5c5e51 MS |
497 | |
498 | if (!err) { | |
499 | /* | |
500 | * Short read means EOF. If file size is larger, truncate it | |
501 | */ | |
502 | if (num_read < count) | |
503 | fuse_read_update_size(inode, pos + num_read, attr_ver); | |
504 | ||
b6aeaded | 505 | SetPageUptodate(page); |
5c5c5e51 MS |
506 | } |
507 | ||
b36c31ba | 508 | fuse_invalidate_attr(inode); /* atime changed */ |
b6aeaded MS |
509 | out: |
510 | unlock_page(page); | |
511 | return err; | |
512 | } | |
513 | ||
c1aa96a5 | 514 | static void fuse_readpages_end(struct fuse_conn *fc, struct fuse_req *req) |
db50b96c | 515 | { |
c1aa96a5 | 516 | int i; |
5c5c5e51 MS |
517 | size_t count = req->misc.read.in.size; |
518 | size_t num_read = req->out.args[0].size; | |
ce534fb0 | 519 | struct address_space *mapping = NULL; |
c1aa96a5 | 520 | |
ce534fb0 MS |
521 | for (i = 0; mapping == NULL && i < req->num_pages; i++) |
522 | mapping = req->pages[i]->mapping; | |
5c5c5e51 | 523 | |
ce534fb0 MS |
524 | if (mapping) { |
525 | struct inode *inode = mapping->host; | |
526 | ||
527 | /* | |
528 | * Short read means EOF. If file size is larger, truncate it | |
529 | */ | |
530 | if (!req->out.h.error && num_read < count) { | |
531 | loff_t pos; | |
532 | ||
533 | pos = page_offset(req->pages[0]) + num_read; | |
534 | fuse_read_update_size(inode, pos, | |
535 | req->misc.read.attr_ver); | |
536 | } | |
537 | fuse_invalidate_attr(inode); /* atime changed */ | |
538 | } | |
c1aa96a5 | 539 | |
db50b96c MS |
540 | for (i = 0; i < req->num_pages; i++) { |
541 | struct page *page = req->pages[i]; | |
542 | if (!req->out.h.error) | |
543 | SetPageUptodate(page); | |
c1aa96a5 MS |
544 | else |
545 | SetPageError(page); | |
db50b96c | 546 | unlock_page(page); |
b5dd3285 | 547 | page_cache_release(page); |
db50b96c | 548 | } |
c756e0a4 MS |
549 | if (req->ff) |
550 | fuse_file_put(req->ff); | |
c1aa96a5 MS |
551 | } |
552 | ||
2106cb18 | 553 | static void fuse_send_readpages(struct fuse_req *req, struct file *file) |
c1aa96a5 | 554 | { |
2106cb18 MS |
555 | struct fuse_file *ff = file->private_data; |
556 | struct fuse_conn *fc = ff->fc; | |
c1aa96a5 MS |
557 | loff_t pos = page_offset(req->pages[0]); |
558 | size_t count = req->num_pages << PAGE_CACHE_SHIFT; | |
f4975c67 MS |
559 | |
560 | req->out.argpages = 1; | |
c1aa96a5 | 561 | req->out.page_zeroing = 1; |
ce534fb0 | 562 | req->out.page_replace = 1; |
2106cb18 | 563 | fuse_read_fill(req, file, pos, count, FUSE_READ); |
5c5c5e51 | 564 | req->misc.read.attr_ver = fuse_get_attr_version(fc); |
9cd68455 | 565 | if (fc->async_read) { |
c756e0a4 | 566 | req->ff = fuse_file_get(ff); |
9cd68455 | 567 | req->end = fuse_readpages_end; |
b93f858a | 568 | fuse_request_send_background(fc, req); |
9cd68455 | 569 | } else { |
b93f858a | 570 | fuse_request_send(fc, req); |
9cd68455 | 571 | fuse_readpages_end(fc, req); |
e9bb09dd | 572 | fuse_put_request(fc, req); |
9cd68455 | 573 | } |
db50b96c MS |
574 | } |
575 | ||
c756e0a4 | 576 | struct fuse_fill_data { |
db50b96c | 577 | struct fuse_req *req; |
a6643094 | 578 | struct file *file; |
db50b96c MS |
579 | struct inode *inode; |
580 | }; | |
581 | ||
582 | static int fuse_readpages_fill(void *_data, struct page *page) | |
583 | { | |
c756e0a4 | 584 | struct fuse_fill_data *data = _data; |
db50b96c MS |
585 | struct fuse_req *req = data->req; |
586 | struct inode *inode = data->inode; | |
587 | struct fuse_conn *fc = get_fuse_conn(inode); | |
588 | ||
3be5a52b MS |
589 | fuse_wait_on_page_writeback(inode, page->index); |
590 | ||
db50b96c MS |
591 | if (req->num_pages && |
592 | (req->num_pages == FUSE_MAX_PAGES_PER_REQ || | |
593 | (req->num_pages + 1) * PAGE_CACHE_SIZE > fc->max_read || | |
594 | req->pages[req->num_pages - 1]->index + 1 != page->index)) { | |
2106cb18 | 595 | fuse_send_readpages(req, data->file); |
ce1d5a49 MS |
596 | data->req = req = fuse_get_req(fc); |
597 | if (IS_ERR(req)) { | |
db50b96c | 598 | unlock_page(page); |
ce1d5a49 | 599 | return PTR_ERR(req); |
db50b96c | 600 | } |
db50b96c | 601 | } |
b5dd3285 | 602 | page_cache_get(page); |
db50b96c | 603 | req->pages[req->num_pages] = page; |
1729a16c | 604 | req->num_pages++; |
db50b96c MS |
605 | return 0; |
606 | } | |
607 | ||
608 | static int fuse_readpages(struct file *file, struct address_space *mapping, | |
609 | struct list_head *pages, unsigned nr_pages) | |
610 | { | |
611 | struct inode *inode = mapping->host; | |
612 | struct fuse_conn *fc = get_fuse_conn(inode); | |
c756e0a4 | 613 | struct fuse_fill_data data; |
db50b96c | 614 | int err; |
248d86e8 | 615 | |
1d7ea732 | 616 | err = -EIO; |
248d86e8 | 617 | if (is_bad_inode(inode)) |
2e990021 | 618 | goto out; |
248d86e8 | 619 | |
a6643094 | 620 | data.file = file; |
db50b96c | 621 | data.inode = inode; |
ce1d5a49 | 622 | data.req = fuse_get_req(fc); |
1d7ea732 | 623 | err = PTR_ERR(data.req); |
ce1d5a49 | 624 | if (IS_ERR(data.req)) |
2e990021 | 625 | goto out; |
db50b96c MS |
626 | |
627 | err = read_cache_pages(mapping, pages, fuse_readpages_fill, &data); | |
d3406ffa MS |
628 | if (!err) { |
629 | if (data.req->num_pages) | |
2106cb18 | 630 | fuse_send_readpages(data.req, file); |
d3406ffa MS |
631 | else |
632 | fuse_put_request(fc, data.req); | |
633 | } | |
2e990021 | 634 | out: |
1d7ea732 | 635 | return err; |
db50b96c MS |
636 | } |
637 | ||
bcb4be80 MS |
638 | static ssize_t fuse_file_aio_read(struct kiocb *iocb, const struct iovec *iov, |
639 | unsigned long nr_segs, loff_t pos) | |
640 | { | |
641 | struct inode *inode = iocb->ki_filp->f_mapping->host; | |
642 | ||
643 | if (pos + iov_length(iov, nr_segs) > i_size_read(inode)) { | |
644 | int err; | |
645 | /* | |
646 | * If trying to read past EOF, make sure the i_size | |
647 | * attribute is up-to-date. | |
648 | */ | |
649 | err = fuse_update_attributes(inode, NULL, iocb->ki_filp, NULL); | |
650 | if (err) | |
651 | return err; | |
652 | } | |
653 | ||
654 | return generic_file_aio_read(iocb, iov, nr_segs, pos); | |
655 | } | |
656 | ||
2d698b07 | 657 | static void fuse_write_fill(struct fuse_req *req, struct fuse_file *ff, |
2106cb18 | 658 | loff_t pos, size_t count) |
b6aeaded | 659 | { |
b25e82e5 MS |
660 | struct fuse_write_in *inarg = &req->misc.write.in; |
661 | struct fuse_write_out *outarg = &req->misc.write.out; | |
b6aeaded | 662 | |
b25e82e5 MS |
663 | inarg->fh = ff->fh; |
664 | inarg->offset = pos; | |
665 | inarg->size = count; | |
b6aeaded | 666 | req->in.h.opcode = FUSE_WRITE; |
2106cb18 | 667 | req->in.h.nodeid = ff->nodeid; |
b6aeaded | 668 | req->in.numargs = 2; |
2106cb18 | 669 | if (ff->fc->minor < 9) |
f3332114 MS |
670 | req->in.args[0].size = FUSE_COMPAT_WRITE_IN_SIZE; |
671 | else | |
672 | req->in.args[0].size = sizeof(struct fuse_write_in); | |
b25e82e5 | 673 | req->in.args[0].value = inarg; |
b6aeaded MS |
674 | req->in.args[1].size = count; |
675 | req->out.numargs = 1; | |
676 | req->out.args[0].size = sizeof(struct fuse_write_out); | |
b25e82e5 MS |
677 | req->out.args[0].value = outarg; |
678 | } | |
679 | ||
680 | static size_t fuse_send_write(struct fuse_req *req, struct file *file, | |
2106cb18 | 681 | loff_t pos, size_t count, fl_owner_t owner) |
b25e82e5 | 682 | { |
2106cb18 MS |
683 | struct fuse_file *ff = file->private_data; |
684 | struct fuse_conn *fc = ff->fc; | |
2d698b07 MS |
685 | struct fuse_write_in *inarg = &req->misc.write.in; |
686 | ||
2106cb18 | 687 | fuse_write_fill(req, ff, pos, count); |
2d698b07 | 688 | inarg->flags = file->f_flags; |
f3332114 | 689 | if (owner != NULL) { |
f3332114 MS |
690 | inarg->write_flags |= FUSE_WRITE_LOCKOWNER; |
691 | inarg->lock_owner = fuse_lock_owner_id(fc, owner); | |
692 | } | |
b93f858a | 693 | fuse_request_send(fc, req); |
b25e82e5 | 694 | return req->misc.write.out.size; |
b6aeaded MS |
695 | } |
696 | ||
5e6f58a1 NP |
697 | static int fuse_write_begin(struct file *file, struct address_space *mapping, |
698 | loff_t pos, unsigned len, unsigned flags, | |
699 | struct page **pagep, void **fsdata) | |
b6aeaded | 700 | { |
5e6f58a1 NP |
701 | pgoff_t index = pos >> PAGE_CACHE_SHIFT; |
702 | ||
54566b2c | 703 | *pagep = grab_cache_page_write_begin(mapping, index, flags); |
5e6f58a1 NP |
704 | if (!*pagep) |
705 | return -ENOMEM; | |
b6aeaded MS |
706 | return 0; |
707 | } | |
708 | ||
854512ec MS |
709 | static void fuse_write_update_size(struct inode *inode, loff_t pos) |
710 | { | |
711 | struct fuse_conn *fc = get_fuse_conn(inode); | |
712 | struct fuse_inode *fi = get_fuse_inode(inode); | |
713 | ||
714 | spin_lock(&fc->lock); | |
715 | fi->attr_version = ++fc->attr_version; | |
716 | if (pos > inode->i_size) | |
717 | i_size_write(inode, pos); | |
718 | spin_unlock(&fc->lock); | |
719 | } | |
720 | ||
5e6f58a1 NP |
721 | static int fuse_buffered_write(struct file *file, struct inode *inode, |
722 | loff_t pos, unsigned count, struct page *page) | |
b6aeaded MS |
723 | { |
724 | int err; | |
04730fef | 725 | size_t nres; |
b6aeaded | 726 | struct fuse_conn *fc = get_fuse_conn(inode); |
5e6f58a1 | 727 | unsigned offset = pos & (PAGE_CACHE_SIZE - 1); |
248d86e8 MS |
728 | struct fuse_req *req; |
729 | ||
730 | if (is_bad_inode(inode)) | |
731 | return -EIO; | |
732 | ||
3be5a52b MS |
733 | /* |
734 | * Make sure writepages on the same page are not mixed up with | |
735 | * plain writes. | |
736 | */ | |
737 | fuse_wait_on_page_writeback(inode, page->index); | |
738 | ||
ce1d5a49 MS |
739 | req = fuse_get_req(fc); |
740 | if (IS_ERR(req)) | |
741 | return PTR_ERR(req); | |
b6aeaded | 742 | |
f4975c67 | 743 | req->in.argpages = 1; |
b6aeaded MS |
744 | req->num_pages = 1; |
745 | req->pages[0] = page; | |
746 | req->page_offset = offset; | |
2106cb18 | 747 | nres = fuse_send_write(req, file, pos, count, NULL); |
b6aeaded MS |
748 | err = req->out.h.error; |
749 | fuse_put_request(fc, req); | |
5e6f58a1 | 750 | if (!err && !nres) |
b6aeaded MS |
751 | err = -EIO; |
752 | if (!err) { | |
5e6f58a1 | 753 | pos += nres; |
854512ec | 754 | fuse_write_update_size(inode, pos); |
5e6f58a1 | 755 | if (count == PAGE_CACHE_SIZE) |
b6aeaded | 756 | SetPageUptodate(page); |
b36c31ba MS |
757 | } |
758 | fuse_invalidate_attr(inode); | |
5e6f58a1 NP |
759 | return err ? err : nres; |
760 | } | |
761 | ||
762 | static int fuse_write_end(struct file *file, struct address_space *mapping, | |
763 | loff_t pos, unsigned len, unsigned copied, | |
764 | struct page *page, void *fsdata) | |
765 | { | |
766 | struct inode *inode = mapping->host; | |
767 | int res = 0; | |
768 | ||
769 | if (copied) | |
770 | res = fuse_buffered_write(file, inode, pos, copied, page); | |
771 | ||
772 | unlock_page(page); | |
773 | page_cache_release(page); | |
774 | return res; | |
b6aeaded MS |
775 | } |
776 | ||
ea9b9907 NP |
777 | static size_t fuse_send_write_pages(struct fuse_req *req, struct file *file, |
778 | struct inode *inode, loff_t pos, | |
779 | size_t count) | |
780 | { | |
781 | size_t res; | |
782 | unsigned offset; | |
783 | unsigned i; | |
784 | ||
785 | for (i = 0; i < req->num_pages; i++) | |
786 | fuse_wait_on_page_writeback(inode, req->pages[i]->index); | |
787 | ||
2106cb18 | 788 | res = fuse_send_write(req, file, pos, count, NULL); |
ea9b9907 NP |
789 | |
790 | offset = req->page_offset; | |
791 | count = res; | |
792 | for (i = 0; i < req->num_pages; i++) { | |
793 | struct page *page = req->pages[i]; | |
794 | ||
795 | if (!req->out.h.error && !offset && count >= PAGE_CACHE_SIZE) | |
796 | SetPageUptodate(page); | |
797 | ||
798 | if (count > PAGE_CACHE_SIZE - offset) | |
799 | count -= PAGE_CACHE_SIZE - offset; | |
800 | else | |
801 | count = 0; | |
802 | offset = 0; | |
803 | ||
804 | unlock_page(page); | |
805 | page_cache_release(page); | |
806 | } | |
807 | ||
808 | return res; | |
809 | } | |
810 | ||
811 | static ssize_t fuse_fill_write_pages(struct fuse_req *req, | |
812 | struct address_space *mapping, | |
813 | struct iov_iter *ii, loff_t pos) | |
814 | { | |
815 | struct fuse_conn *fc = get_fuse_conn(mapping->host); | |
816 | unsigned offset = pos & (PAGE_CACHE_SIZE - 1); | |
817 | size_t count = 0; | |
818 | int err; | |
819 | ||
f4975c67 | 820 | req->in.argpages = 1; |
ea9b9907 NP |
821 | req->page_offset = offset; |
822 | ||
823 | do { | |
824 | size_t tmp; | |
825 | struct page *page; | |
826 | pgoff_t index = pos >> PAGE_CACHE_SHIFT; | |
827 | size_t bytes = min_t(size_t, PAGE_CACHE_SIZE - offset, | |
828 | iov_iter_count(ii)); | |
829 | ||
830 | bytes = min_t(size_t, bytes, fc->max_write - count); | |
831 | ||
832 | again: | |
833 | err = -EFAULT; | |
834 | if (iov_iter_fault_in_readable(ii, bytes)) | |
835 | break; | |
836 | ||
837 | err = -ENOMEM; | |
54566b2c | 838 | page = grab_cache_page_write_begin(mapping, index, 0); |
ea9b9907 NP |
839 | if (!page) |
840 | break; | |
841 | ||
931e80e4 | 842 | if (mapping_writably_mapped(mapping)) |
843 | flush_dcache_page(page); | |
844 | ||
ea9b9907 NP |
845 | pagefault_disable(); |
846 | tmp = iov_iter_copy_from_user_atomic(page, ii, offset, bytes); | |
847 | pagefault_enable(); | |
848 | flush_dcache_page(page); | |
849 | ||
850 | if (!tmp) { | |
851 | unlock_page(page); | |
852 | page_cache_release(page); | |
853 | bytes = min(bytes, iov_iter_single_seg_count(ii)); | |
854 | goto again; | |
855 | } | |
856 | ||
857 | err = 0; | |
858 | req->pages[req->num_pages] = page; | |
859 | req->num_pages++; | |
860 | ||
861 | iov_iter_advance(ii, tmp); | |
862 | count += tmp; | |
863 | pos += tmp; | |
864 | offset += tmp; | |
865 | if (offset == PAGE_CACHE_SIZE) | |
866 | offset = 0; | |
867 | ||
78bb6cb9 MS |
868 | if (!fc->big_writes) |
869 | break; | |
ea9b9907 NP |
870 | } while (iov_iter_count(ii) && count < fc->max_write && |
871 | req->num_pages < FUSE_MAX_PAGES_PER_REQ && offset == 0); | |
872 | ||
873 | return count > 0 ? count : err; | |
874 | } | |
875 | ||
876 | static ssize_t fuse_perform_write(struct file *file, | |
877 | struct address_space *mapping, | |
878 | struct iov_iter *ii, loff_t pos) | |
879 | { | |
880 | struct inode *inode = mapping->host; | |
881 | struct fuse_conn *fc = get_fuse_conn(inode); | |
882 | int err = 0; | |
883 | ssize_t res = 0; | |
884 | ||
885 | if (is_bad_inode(inode)) | |
886 | return -EIO; | |
887 | ||
888 | do { | |
889 | struct fuse_req *req; | |
890 | ssize_t count; | |
891 | ||
892 | req = fuse_get_req(fc); | |
893 | if (IS_ERR(req)) { | |
894 | err = PTR_ERR(req); | |
895 | break; | |
896 | } | |
897 | ||
898 | count = fuse_fill_write_pages(req, mapping, ii, pos); | |
899 | if (count <= 0) { | |
900 | err = count; | |
901 | } else { | |
902 | size_t num_written; | |
903 | ||
904 | num_written = fuse_send_write_pages(req, file, inode, | |
905 | pos, count); | |
906 | err = req->out.h.error; | |
907 | if (!err) { | |
908 | res += num_written; | |
909 | pos += num_written; | |
910 | ||
911 | /* break out of the loop on short write */ | |
912 | if (num_written != count) | |
913 | err = -EIO; | |
914 | } | |
915 | } | |
916 | fuse_put_request(fc, req); | |
917 | } while (!err && iov_iter_count(ii)); | |
918 | ||
919 | if (res > 0) | |
920 | fuse_write_update_size(inode, pos); | |
921 | ||
922 | fuse_invalidate_attr(inode); | |
923 | ||
924 | return res > 0 ? res : err; | |
925 | } | |
926 | ||
927 | static ssize_t fuse_file_aio_write(struct kiocb *iocb, const struct iovec *iov, | |
928 | unsigned long nr_segs, loff_t pos) | |
929 | { | |
930 | struct file *file = iocb->ki_filp; | |
931 | struct address_space *mapping = file->f_mapping; | |
932 | size_t count = 0; | |
933 | ssize_t written = 0; | |
934 | struct inode *inode = mapping->host; | |
935 | ssize_t err; | |
936 | struct iov_iter i; | |
937 | ||
938 | WARN_ON(iocb->ki_pos != pos); | |
939 | ||
940 | err = generic_segment_checks(iov, &nr_segs, &count, VERIFY_READ); | |
941 | if (err) | |
942 | return err; | |
943 | ||
944 | mutex_lock(&inode->i_mutex); | |
945 | vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE); | |
946 | ||
947 | /* We can write back this queue in page reclaim */ | |
948 | current->backing_dev_info = mapping->backing_dev_info; | |
949 | ||
950 | err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode)); | |
951 | if (err) | |
952 | goto out; | |
953 | ||
954 | if (count == 0) | |
955 | goto out; | |
956 | ||
2f1936b8 | 957 | err = file_remove_suid(file); |
ea9b9907 NP |
958 | if (err) |
959 | goto out; | |
960 | ||
961 | file_update_time(file); | |
962 | ||
963 | iov_iter_init(&i, iov, nr_segs, count, 0); | |
964 | written = fuse_perform_write(file, mapping, &i, pos); | |
965 | if (written >= 0) | |
966 | iocb->ki_pos = pos + written; | |
967 | ||
968 | out: | |
969 | current->backing_dev_info = NULL; | |
970 | mutex_unlock(&inode->i_mutex); | |
971 | ||
972 | return written ? written : err; | |
973 | } | |
974 | ||
413ef8cb MS |
975 | static void fuse_release_user_pages(struct fuse_req *req, int write) |
976 | { | |
977 | unsigned i; | |
978 | ||
979 | for (i = 0; i < req->num_pages; i++) { | |
980 | struct page *page = req->pages[i]; | |
981 | if (write) | |
982 | set_page_dirty_lock(page); | |
983 | put_page(page); | |
984 | } | |
985 | } | |
986 | ||
987 | static int fuse_get_user_pages(struct fuse_req *req, const char __user *buf, | |
ce60a2f1 | 988 | size_t *nbytesp, int write) |
413ef8cb | 989 | { |
ce60a2f1 | 990 | size_t nbytes = *nbytesp; |
413ef8cb MS |
991 | unsigned long user_addr = (unsigned long) buf; |
992 | unsigned offset = user_addr & ~PAGE_MASK; | |
993 | int npages; | |
994 | ||
f4975c67 MS |
995 | /* Special case for kernel I/O: can copy directly into the buffer */ |
996 | if (segment_eq(get_fs(), KERNEL_DS)) { | |
997 | if (write) | |
998 | req->in.args[1].value = (void *) user_addr; | |
999 | else | |
1000 | req->out.args[0].value = (void *) user_addr; | |
1001 | ||
1002 | return 0; | |
1003 | } | |
413ef8cb | 1004 | |
ce60a2f1 | 1005 | nbytes = min_t(size_t, nbytes, FUSE_MAX_PAGES_PER_REQ << PAGE_SHIFT); |
413ef8cb | 1006 | npages = (nbytes + offset + PAGE_SIZE - 1) >> PAGE_SHIFT; |
bd730967 | 1007 | npages = clamp(npages, 1, FUSE_MAX_PAGES_PER_REQ); |
1bf94ca7 | 1008 | npages = get_user_pages_fast(user_addr, npages, !write, req->pages); |
413ef8cb MS |
1009 | if (npages < 0) |
1010 | return npages; | |
1011 | ||
1012 | req->num_pages = npages; | |
1013 | req->page_offset = offset; | |
f4975c67 MS |
1014 | |
1015 | if (write) | |
1016 | req->in.argpages = 1; | |
1017 | else | |
1018 | req->out.argpages = 1; | |
1019 | ||
1020 | nbytes = (req->num_pages << PAGE_SHIFT) - req->page_offset; | |
1021 | *nbytesp = min(*nbytesp, nbytes); | |
1022 | ||
413ef8cb MS |
1023 | return 0; |
1024 | } | |
1025 | ||
08cbf542 TH |
1026 | ssize_t fuse_direct_io(struct file *file, const char __user *buf, |
1027 | size_t count, loff_t *ppos, int write) | |
413ef8cb | 1028 | { |
2106cb18 MS |
1029 | struct fuse_file *ff = file->private_data; |
1030 | struct fuse_conn *fc = ff->fc; | |
413ef8cb MS |
1031 | size_t nmax = write ? fc->max_write : fc->max_read; |
1032 | loff_t pos = *ppos; | |
1033 | ssize_t res = 0; | |
248d86e8 MS |
1034 | struct fuse_req *req; |
1035 | ||
ce1d5a49 MS |
1036 | req = fuse_get_req(fc); |
1037 | if (IS_ERR(req)) | |
1038 | return PTR_ERR(req); | |
413ef8cb MS |
1039 | |
1040 | while (count) { | |
413ef8cb | 1041 | size_t nres; |
2106cb18 | 1042 | fl_owner_t owner = current->files; |
f4975c67 MS |
1043 | size_t nbytes = min(count, nmax); |
1044 | int err = fuse_get_user_pages(req, buf, &nbytes, write); | |
413ef8cb MS |
1045 | if (err) { |
1046 | res = err; | |
1047 | break; | |
1048 | } | |
f4975c67 | 1049 | |
413ef8cb | 1050 | if (write) |
2106cb18 | 1051 | nres = fuse_send_write(req, file, pos, nbytes, owner); |
413ef8cb | 1052 | else |
2106cb18 MS |
1053 | nres = fuse_send_read(req, file, pos, nbytes, owner); |
1054 | ||
413ef8cb MS |
1055 | fuse_release_user_pages(req, !write); |
1056 | if (req->out.h.error) { | |
1057 | if (!res) | |
1058 | res = req->out.h.error; | |
1059 | break; | |
1060 | } else if (nres > nbytes) { | |
1061 | res = -EIO; | |
1062 | break; | |
1063 | } | |
1064 | count -= nres; | |
1065 | res += nres; | |
1066 | pos += nres; | |
1067 | buf += nres; | |
1068 | if (nres != nbytes) | |
1069 | break; | |
56cf34ff MS |
1070 | if (count) { |
1071 | fuse_put_request(fc, req); | |
1072 | req = fuse_get_req(fc); | |
1073 | if (IS_ERR(req)) | |
1074 | break; | |
1075 | } | |
413ef8cb | 1076 | } |
f60311d5 AA |
1077 | if (!IS_ERR(req)) |
1078 | fuse_put_request(fc, req); | |
d09cb9d7 | 1079 | if (res > 0) |
413ef8cb | 1080 | *ppos = pos; |
413ef8cb MS |
1081 | |
1082 | return res; | |
1083 | } | |
08cbf542 | 1084 | EXPORT_SYMBOL_GPL(fuse_direct_io); |
413ef8cb MS |
1085 | |
1086 | static ssize_t fuse_direct_read(struct file *file, char __user *buf, | |
1087 | size_t count, loff_t *ppos) | |
1088 | { | |
d09cb9d7 MS |
1089 | ssize_t res; |
1090 | struct inode *inode = file->f_path.dentry->d_inode; | |
1091 | ||
1092 | if (is_bad_inode(inode)) | |
1093 | return -EIO; | |
1094 | ||
1095 | res = fuse_direct_io(file, buf, count, ppos, 0); | |
1096 | ||
1097 | fuse_invalidate_attr(inode); | |
1098 | ||
1099 | return res; | |
413ef8cb MS |
1100 | } |
1101 | ||
1102 | static ssize_t fuse_direct_write(struct file *file, const char __user *buf, | |
1103 | size_t count, loff_t *ppos) | |
1104 | { | |
7706a9d6 | 1105 | struct inode *inode = file->f_path.dentry->d_inode; |
413ef8cb | 1106 | ssize_t res; |
d09cb9d7 MS |
1107 | |
1108 | if (is_bad_inode(inode)) | |
1109 | return -EIO; | |
1110 | ||
413ef8cb | 1111 | /* Don't allow parallel writes to the same file */ |
1b1dcc1b | 1112 | mutex_lock(&inode->i_mutex); |
889f7848 | 1113 | res = generic_write_checks(file, ppos, &count, 0); |
d09cb9d7 | 1114 | if (!res) { |
889f7848 | 1115 | res = fuse_direct_io(file, buf, count, ppos, 1); |
d09cb9d7 MS |
1116 | if (res > 0) |
1117 | fuse_write_update_size(inode, *ppos); | |
1118 | } | |
1b1dcc1b | 1119 | mutex_unlock(&inode->i_mutex); |
d09cb9d7 MS |
1120 | |
1121 | fuse_invalidate_attr(inode); | |
1122 | ||
413ef8cb MS |
1123 | return res; |
1124 | } | |
1125 | ||
3be5a52b | 1126 | static void fuse_writepage_free(struct fuse_conn *fc, struct fuse_req *req) |
b6aeaded | 1127 | { |
3be5a52b MS |
1128 | __free_page(req->pages[0]); |
1129 | fuse_file_put(req->ff); | |
3be5a52b MS |
1130 | } |
1131 | ||
1132 | static void fuse_writepage_finish(struct fuse_conn *fc, struct fuse_req *req) | |
1133 | { | |
1134 | struct inode *inode = req->inode; | |
1135 | struct fuse_inode *fi = get_fuse_inode(inode); | |
1136 | struct backing_dev_info *bdi = inode->i_mapping->backing_dev_info; | |
1137 | ||
1138 | list_del(&req->writepages_entry); | |
1139 | dec_bdi_stat(bdi, BDI_WRITEBACK); | |
1140 | dec_zone_page_state(req->pages[0], NR_WRITEBACK_TEMP); | |
1141 | bdi_writeout_inc(bdi); | |
1142 | wake_up(&fi->page_waitq); | |
1143 | } | |
1144 | ||
1145 | /* Called under fc->lock, may release and reacquire it */ | |
1146 | static void fuse_send_writepage(struct fuse_conn *fc, struct fuse_req *req) | |
5d9ec854 HH |
1147 | __releases(&fc->lock) |
1148 | __acquires(&fc->lock) | |
3be5a52b MS |
1149 | { |
1150 | struct fuse_inode *fi = get_fuse_inode(req->inode); | |
1151 | loff_t size = i_size_read(req->inode); | |
1152 | struct fuse_write_in *inarg = &req->misc.write.in; | |
1153 | ||
1154 | if (!fc->connected) | |
1155 | goto out_free; | |
1156 | ||
1157 | if (inarg->offset + PAGE_CACHE_SIZE <= size) { | |
1158 | inarg->size = PAGE_CACHE_SIZE; | |
1159 | } else if (inarg->offset < size) { | |
1160 | inarg->size = size & (PAGE_CACHE_SIZE - 1); | |
1161 | } else { | |
1162 | /* Got truncated off completely */ | |
1163 | goto out_free; | |
b6aeaded | 1164 | } |
3be5a52b MS |
1165 | |
1166 | req->in.args[1].size = inarg->size; | |
1167 | fi->writectr++; | |
b93f858a | 1168 | fuse_request_send_background_locked(fc, req); |
3be5a52b MS |
1169 | return; |
1170 | ||
1171 | out_free: | |
1172 | fuse_writepage_finish(fc, req); | |
1173 | spin_unlock(&fc->lock); | |
1174 | fuse_writepage_free(fc, req); | |
e9bb09dd | 1175 | fuse_put_request(fc, req); |
3be5a52b | 1176 | spin_lock(&fc->lock); |
b6aeaded MS |
1177 | } |
1178 | ||
3be5a52b MS |
1179 | /* |
1180 | * If fi->writectr is positive (no truncate or fsync going on) send | |
1181 | * all queued writepage requests. | |
1182 | * | |
1183 | * Called with fc->lock | |
1184 | */ | |
1185 | void fuse_flush_writepages(struct inode *inode) | |
5d9ec854 HH |
1186 | __releases(&fc->lock) |
1187 | __acquires(&fc->lock) | |
b6aeaded | 1188 | { |
3be5a52b MS |
1189 | struct fuse_conn *fc = get_fuse_conn(inode); |
1190 | struct fuse_inode *fi = get_fuse_inode(inode); | |
1191 | struct fuse_req *req; | |
1192 | ||
1193 | while (fi->writectr >= 0 && !list_empty(&fi->queued_writes)) { | |
1194 | req = list_entry(fi->queued_writes.next, struct fuse_req, list); | |
1195 | list_del_init(&req->list); | |
1196 | fuse_send_writepage(fc, req); | |
1197 | } | |
1198 | } | |
1199 | ||
1200 | static void fuse_writepage_end(struct fuse_conn *fc, struct fuse_req *req) | |
1201 | { | |
1202 | struct inode *inode = req->inode; | |
1203 | struct fuse_inode *fi = get_fuse_inode(inode); | |
1204 | ||
1205 | mapping_set_error(inode->i_mapping, req->out.h.error); | |
1206 | spin_lock(&fc->lock); | |
1207 | fi->writectr--; | |
1208 | fuse_writepage_finish(fc, req); | |
1209 | spin_unlock(&fc->lock); | |
1210 | fuse_writepage_free(fc, req); | |
1211 | } | |
1212 | ||
1213 | static int fuse_writepage_locked(struct page *page) | |
1214 | { | |
1215 | struct address_space *mapping = page->mapping; | |
1216 | struct inode *inode = mapping->host; | |
1217 | struct fuse_conn *fc = get_fuse_conn(inode); | |
1218 | struct fuse_inode *fi = get_fuse_inode(inode); | |
1219 | struct fuse_req *req; | |
1220 | struct fuse_file *ff; | |
1221 | struct page *tmp_page; | |
1222 | ||
1223 | set_page_writeback(page); | |
1224 | ||
1225 | req = fuse_request_alloc_nofs(); | |
1226 | if (!req) | |
1227 | goto err; | |
1228 | ||
1229 | tmp_page = alloc_page(GFP_NOFS | __GFP_HIGHMEM); | |
1230 | if (!tmp_page) | |
1231 | goto err_free; | |
1232 | ||
1233 | spin_lock(&fc->lock); | |
1234 | BUG_ON(list_empty(&fi->write_files)); | |
1235 | ff = list_entry(fi->write_files.next, struct fuse_file, write_entry); | |
1236 | req->ff = fuse_file_get(ff); | |
1237 | spin_unlock(&fc->lock); | |
1238 | ||
2106cb18 | 1239 | fuse_write_fill(req, ff, page_offset(page), 0); |
3be5a52b MS |
1240 | |
1241 | copy_highpage(tmp_page, page); | |
2d698b07 | 1242 | req->misc.write.in.write_flags |= FUSE_WRITE_CACHE; |
f4975c67 | 1243 | req->in.argpages = 1; |
3be5a52b MS |
1244 | req->num_pages = 1; |
1245 | req->pages[0] = tmp_page; | |
1246 | req->page_offset = 0; | |
1247 | req->end = fuse_writepage_end; | |
1248 | req->inode = inode; | |
1249 | ||
1250 | inc_bdi_stat(mapping->backing_dev_info, BDI_WRITEBACK); | |
1251 | inc_zone_page_state(tmp_page, NR_WRITEBACK_TEMP); | |
1252 | end_page_writeback(page); | |
1253 | ||
1254 | spin_lock(&fc->lock); | |
1255 | list_add(&req->writepages_entry, &fi->writepages); | |
1256 | list_add_tail(&req->list, &fi->queued_writes); | |
1257 | fuse_flush_writepages(inode); | |
1258 | spin_unlock(&fc->lock); | |
1259 | ||
1260 | return 0; | |
1261 | ||
1262 | err_free: | |
1263 | fuse_request_free(req); | |
1264 | err: | |
1265 | end_page_writeback(page); | |
1266 | return -ENOMEM; | |
1267 | } | |
1268 | ||
1269 | static int fuse_writepage(struct page *page, struct writeback_control *wbc) | |
1270 | { | |
1271 | int err; | |
1272 | ||
1273 | err = fuse_writepage_locked(page); | |
1274 | unlock_page(page); | |
1275 | ||
1276 | return err; | |
1277 | } | |
1278 | ||
1279 | static int fuse_launder_page(struct page *page) | |
1280 | { | |
1281 | int err = 0; | |
1282 | if (clear_page_dirty_for_io(page)) { | |
1283 | struct inode *inode = page->mapping->host; | |
1284 | err = fuse_writepage_locked(page); | |
1285 | if (!err) | |
1286 | fuse_wait_on_page_writeback(inode, page->index); | |
1287 | } | |
1288 | return err; | |
1289 | } | |
1290 | ||
1291 | /* | |
1292 | * Write back dirty pages now, because there may not be any suitable | |
1293 | * open files later | |
1294 | */ | |
1295 | static void fuse_vma_close(struct vm_area_struct *vma) | |
1296 | { | |
1297 | filemap_write_and_wait(vma->vm_file->f_mapping); | |
1298 | } | |
1299 | ||
1300 | /* | |
1301 | * Wait for writeback against this page to complete before allowing it | |
1302 | * to be marked dirty again, and hence written back again, possibly | |
1303 | * before the previous writepage completed. | |
1304 | * | |
1305 | * Block here, instead of in ->writepage(), so that the userspace fs | |
1306 | * can only block processes actually operating on the filesystem. | |
1307 | * | |
1308 | * Otherwise unprivileged userspace fs would be able to block | |
1309 | * unrelated: | |
1310 | * | |
1311 | * - page migration | |
1312 | * - sync(2) | |
1313 | * - try_to_free_pages() with order > PAGE_ALLOC_COSTLY_ORDER | |
1314 | */ | |
c2ec175c | 1315 | static int fuse_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) |
3be5a52b | 1316 | { |
c2ec175c | 1317 | struct page *page = vmf->page; |
3be5a52b MS |
1318 | /* |
1319 | * Don't use page->mapping as it may become NULL from a | |
1320 | * concurrent truncate. | |
1321 | */ | |
1322 | struct inode *inode = vma->vm_file->f_mapping->host; | |
1323 | ||
1324 | fuse_wait_on_page_writeback(inode, page->index); | |
1325 | return 0; | |
1326 | } | |
1327 | ||
f0f37e2f | 1328 | static const struct vm_operations_struct fuse_file_vm_ops = { |
3be5a52b MS |
1329 | .close = fuse_vma_close, |
1330 | .fault = filemap_fault, | |
1331 | .page_mkwrite = fuse_page_mkwrite, | |
1332 | }; | |
1333 | ||
1334 | static int fuse_file_mmap(struct file *file, struct vm_area_struct *vma) | |
1335 | { | |
1336 | if ((vma->vm_flags & VM_SHARED) && (vma->vm_flags & VM_MAYWRITE)) { | |
1337 | struct inode *inode = file->f_dentry->d_inode; | |
1338 | struct fuse_conn *fc = get_fuse_conn(inode); | |
1339 | struct fuse_inode *fi = get_fuse_inode(inode); | |
1340 | struct fuse_file *ff = file->private_data; | |
1341 | /* | |
1342 | * file may be written through mmap, so chain it onto the | |
1343 | * inodes's write_file list | |
1344 | */ | |
1345 | spin_lock(&fc->lock); | |
1346 | if (list_empty(&ff->write_entry)) | |
1347 | list_add(&ff->write_entry, &fi->write_files); | |
1348 | spin_unlock(&fc->lock); | |
1349 | } | |
1350 | file_accessed(file); | |
1351 | vma->vm_ops = &fuse_file_vm_ops; | |
b6aeaded MS |
1352 | return 0; |
1353 | } | |
1354 | ||
fc280c96 MS |
1355 | static int fuse_direct_mmap(struct file *file, struct vm_area_struct *vma) |
1356 | { | |
1357 | /* Can't provide the coherency needed for MAP_SHARED */ | |
1358 | if (vma->vm_flags & VM_MAYSHARE) | |
1359 | return -ENODEV; | |
1360 | ||
3121bfe7 MS |
1361 | invalidate_inode_pages2(file->f_mapping); |
1362 | ||
fc280c96 MS |
1363 | return generic_file_mmap(file, vma); |
1364 | } | |
1365 | ||
71421259 MS |
1366 | static int convert_fuse_file_lock(const struct fuse_file_lock *ffl, |
1367 | struct file_lock *fl) | |
1368 | { | |
1369 | switch (ffl->type) { | |
1370 | case F_UNLCK: | |
1371 | break; | |
1372 | ||
1373 | case F_RDLCK: | |
1374 | case F_WRLCK: | |
1375 | if (ffl->start > OFFSET_MAX || ffl->end > OFFSET_MAX || | |
1376 | ffl->end < ffl->start) | |
1377 | return -EIO; | |
1378 | ||
1379 | fl->fl_start = ffl->start; | |
1380 | fl->fl_end = ffl->end; | |
1381 | fl->fl_pid = ffl->pid; | |
1382 | break; | |
1383 | ||
1384 | default: | |
1385 | return -EIO; | |
1386 | } | |
1387 | fl->fl_type = ffl->type; | |
1388 | return 0; | |
1389 | } | |
1390 | ||
1391 | static void fuse_lk_fill(struct fuse_req *req, struct file *file, | |
a9ff4f87 MS |
1392 | const struct file_lock *fl, int opcode, pid_t pid, |
1393 | int flock) | |
71421259 | 1394 | { |
7706a9d6 | 1395 | struct inode *inode = file->f_path.dentry->d_inode; |
9c8ef561 | 1396 | struct fuse_conn *fc = get_fuse_conn(inode); |
71421259 MS |
1397 | struct fuse_file *ff = file->private_data; |
1398 | struct fuse_lk_in *arg = &req->misc.lk_in; | |
1399 | ||
1400 | arg->fh = ff->fh; | |
9c8ef561 | 1401 | arg->owner = fuse_lock_owner_id(fc, fl->fl_owner); |
71421259 MS |
1402 | arg->lk.start = fl->fl_start; |
1403 | arg->lk.end = fl->fl_end; | |
1404 | arg->lk.type = fl->fl_type; | |
1405 | arg->lk.pid = pid; | |
a9ff4f87 MS |
1406 | if (flock) |
1407 | arg->lk_flags |= FUSE_LK_FLOCK; | |
71421259 MS |
1408 | req->in.h.opcode = opcode; |
1409 | req->in.h.nodeid = get_node_id(inode); | |
1410 | req->in.numargs = 1; | |
1411 | req->in.args[0].size = sizeof(*arg); | |
1412 | req->in.args[0].value = arg; | |
1413 | } | |
1414 | ||
1415 | static int fuse_getlk(struct file *file, struct file_lock *fl) | |
1416 | { | |
7706a9d6 | 1417 | struct inode *inode = file->f_path.dentry->d_inode; |
71421259 MS |
1418 | struct fuse_conn *fc = get_fuse_conn(inode); |
1419 | struct fuse_req *req; | |
1420 | struct fuse_lk_out outarg; | |
1421 | int err; | |
1422 | ||
1423 | req = fuse_get_req(fc); | |
1424 | if (IS_ERR(req)) | |
1425 | return PTR_ERR(req); | |
1426 | ||
a9ff4f87 | 1427 | fuse_lk_fill(req, file, fl, FUSE_GETLK, 0, 0); |
71421259 MS |
1428 | req->out.numargs = 1; |
1429 | req->out.args[0].size = sizeof(outarg); | |
1430 | req->out.args[0].value = &outarg; | |
b93f858a | 1431 | fuse_request_send(fc, req); |
71421259 MS |
1432 | err = req->out.h.error; |
1433 | fuse_put_request(fc, req); | |
1434 | if (!err) | |
1435 | err = convert_fuse_file_lock(&outarg.lk, fl); | |
1436 | ||
1437 | return err; | |
1438 | } | |
1439 | ||
a9ff4f87 | 1440 | static int fuse_setlk(struct file *file, struct file_lock *fl, int flock) |
71421259 | 1441 | { |
7706a9d6 | 1442 | struct inode *inode = file->f_path.dentry->d_inode; |
71421259 MS |
1443 | struct fuse_conn *fc = get_fuse_conn(inode); |
1444 | struct fuse_req *req; | |
1445 | int opcode = (fl->fl_flags & FL_SLEEP) ? FUSE_SETLKW : FUSE_SETLK; | |
1446 | pid_t pid = fl->fl_type != F_UNLCK ? current->tgid : 0; | |
1447 | int err; | |
1448 | ||
48e90761 MS |
1449 | if (fl->fl_lmops && fl->fl_lmops->fl_grant) { |
1450 | /* NLM needs asynchronous locks, which we don't support yet */ | |
1451 | return -ENOLCK; | |
1452 | } | |
1453 | ||
71421259 MS |
1454 | /* Unlock on close is handled by the flush method */ |
1455 | if (fl->fl_flags & FL_CLOSE) | |
1456 | return 0; | |
1457 | ||
1458 | req = fuse_get_req(fc); | |
1459 | if (IS_ERR(req)) | |
1460 | return PTR_ERR(req); | |
1461 | ||
a9ff4f87 | 1462 | fuse_lk_fill(req, file, fl, opcode, pid, flock); |
b93f858a | 1463 | fuse_request_send(fc, req); |
71421259 | 1464 | err = req->out.h.error; |
a4d27e75 MS |
1465 | /* locking is restartable */ |
1466 | if (err == -EINTR) | |
1467 | err = -ERESTARTSYS; | |
71421259 MS |
1468 | fuse_put_request(fc, req); |
1469 | return err; | |
1470 | } | |
1471 | ||
1472 | static int fuse_file_lock(struct file *file, int cmd, struct file_lock *fl) | |
1473 | { | |
7706a9d6 | 1474 | struct inode *inode = file->f_path.dentry->d_inode; |
71421259 MS |
1475 | struct fuse_conn *fc = get_fuse_conn(inode); |
1476 | int err; | |
1477 | ||
48e90761 MS |
1478 | if (cmd == F_CANCELLK) { |
1479 | err = 0; | |
1480 | } else if (cmd == F_GETLK) { | |
71421259 | 1481 | if (fc->no_lock) { |
9d6a8c5c | 1482 | posix_test_lock(file, fl); |
71421259 MS |
1483 | err = 0; |
1484 | } else | |
1485 | err = fuse_getlk(file, fl); | |
1486 | } else { | |
1487 | if (fc->no_lock) | |
48e90761 | 1488 | err = posix_lock_file(file, fl, NULL); |
71421259 | 1489 | else |
a9ff4f87 | 1490 | err = fuse_setlk(file, fl, 0); |
71421259 MS |
1491 | } |
1492 | return err; | |
1493 | } | |
1494 | ||
a9ff4f87 MS |
1495 | static int fuse_file_flock(struct file *file, int cmd, struct file_lock *fl) |
1496 | { | |
1497 | struct inode *inode = file->f_path.dentry->d_inode; | |
1498 | struct fuse_conn *fc = get_fuse_conn(inode); | |
1499 | int err; | |
1500 | ||
1501 | if (fc->no_lock) { | |
1502 | err = flock_lock_file_wait(file, fl); | |
1503 | } else { | |
1504 | /* emulate flock with POSIX locks */ | |
1505 | fl->fl_owner = (fl_owner_t) file; | |
1506 | err = fuse_setlk(file, fl, 1); | |
1507 | } | |
1508 | ||
1509 | return err; | |
1510 | } | |
1511 | ||
b2d2272f MS |
1512 | static sector_t fuse_bmap(struct address_space *mapping, sector_t block) |
1513 | { | |
1514 | struct inode *inode = mapping->host; | |
1515 | struct fuse_conn *fc = get_fuse_conn(inode); | |
1516 | struct fuse_req *req; | |
1517 | struct fuse_bmap_in inarg; | |
1518 | struct fuse_bmap_out outarg; | |
1519 | int err; | |
1520 | ||
1521 | if (!inode->i_sb->s_bdev || fc->no_bmap) | |
1522 | return 0; | |
1523 | ||
1524 | req = fuse_get_req(fc); | |
1525 | if (IS_ERR(req)) | |
1526 | return 0; | |
1527 | ||
1528 | memset(&inarg, 0, sizeof(inarg)); | |
1529 | inarg.block = block; | |
1530 | inarg.blocksize = inode->i_sb->s_blocksize; | |
1531 | req->in.h.opcode = FUSE_BMAP; | |
1532 | req->in.h.nodeid = get_node_id(inode); | |
1533 | req->in.numargs = 1; | |
1534 | req->in.args[0].size = sizeof(inarg); | |
1535 | req->in.args[0].value = &inarg; | |
1536 | req->out.numargs = 1; | |
1537 | req->out.args[0].size = sizeof(outarg); | |
1538 | req->out.args[0].value = &outarg; | |
b93f858a | 1539 | fuse_request_send(fc, req); |
b2d2272f MS |
1540 | err = req->out.h.error; |
1541 | fuse_put_request(fc, req); | |
1542 | if (err == -ENOSYS) | |
1543 | fc->no_bmap = 1; | |
1544 | ||
1545 | return err ? 0 : outarg.block; | |
1546 | } | |
1547 | ||
5559b8f4 MS |
1548 | static loff_t fuse_file_llseek(struct file *file, loff_t offset, int origin) |
1549 | { | |
1550 | loff_t retval; | |
1551 | struct inode *inode = file->f_path.dentry->d_inode; | |
1552 | ||
1553 | mutex_lock(&inode->i_mutex); | |
1554 | switch (origin) { | |
1555 | case SEEK_END: | |
769415c6 MS |
1556 | retval = fuse_update_attributes(inode, NULL, file, NULL); |
1557 | if (retval) | |
5291658d | 1558 | goto exit; |
5559b8f4 MS |
1559 | offset += i_size_read(inode); |
1560 | break; | |
1561 | case SEEK_CUR: | |
1562 | offset += file->f_pos; | |
1563 | } | |
1564 | retval = -EINVAL; | |
1565 | if (offset >= 0 && offset <= inode->i_sb->s_maxbytes) { | |
1566 | if (offset != file->f_pos) { | |
1567 | file->f_pos = offset; | |
1568 | file->f_version = 0; | |
1569 | } | |
1570 | retval = offset; | |
1571 | } | |
5291658d | 1572 | exit: |
5559b8f4 MS |
1573 | mutex_unlock(&inode->i_mutex); |
1574 | return retval; | |
1575 | } | |
1576 | ||
59efec7b TH |
1577 | static int fuse_ioctl_copy_user(struct page **pages, struct iovec *iov, |
1578 | unsigned int nr_segs, size_t bytes, bool to_user) | |
1579 | { | |
1580 | struct iov_iter ii; | |
1581 | int page_idx = 0; | |
1582 | ||
1583 | if (!bytes) | |
1584 | return 0; | |
1585 | ||
1586 | iov_iter_init(&ii, iov, nr_segs, bytes, 0); | |
1587 | ||
1588 | while (iov_iter_count(&ii)) { | |
1589 | struct page *page = pages[page_idx++]; | |
1590 | size_t todo = min_t(size_t, PAGE_SIZE, iov_iter_count(&ii)); | |
4aa0edd2 | 1591 | void *kaddr; |
59efec7b | 1592 | |
4aa0edd2 | 1593 | kaddr = kmap(page); |
59efec7b TH |
1594 | |
1595 | while (todo) { | |
1596 | char __user *uaddr = ii.iov->iov_base + ii.iov_offset; | |
1597 | size_t iov_len = ii.iov->iov_len - ii.iov_offset; | |
1598 | size_t copy = min(todo, iov_len); | |
1599 | size_t left; | |
1600 | ||
1601 | if (!to_user) | |
1602 | left = copy_from_user(kaddr, uaddr, copy); | |
1603 | else | |
1604 | left = copy_to_user(uaddr, kaddr, copy); | |
1605 | ||
1606 | if (unlikely(left)) | |
1607 | return -EFAULT; | |
1608 | ||
1609 | iov_iter_advance(&ii, copy); | |
1610 | todo -= copy; | |
1611 | kaddr += copy; | |
1612 | } | |
1613 | ||
0bd87182 | 1614 | kunmap(page); |
59efec7b TH |
1615 | } |
1616 | ||
1617 | return 0; | |
1618 | } | |
1619 | ||
1620 | /* | |
1621 | * For ioctls, there is no generic way to determine how much memory | |
1622 | * needs to be read and/or written. Furthermore, ioctls are allowed | |
1623 | * to dereference the passed pointer, so the parameter requires deep | |
1624 | * copying but FUSE has no idea whatsoever about what to copy in or | |
1625 | * out. | |
1626 | * | |
1627 | * This is solved by allowing FUSE server to retry ioctl with | |
1628 | * necessary in/out iovecs. Let's assume the ioctl implementation | |
1629 | * needs to read in the following structure. | |
1630 | * | |
1631 | * struct a { | |
1632 | * char *buf; | |
1633 | * size_t buflen; | |
1634 | * } | |
1635 | * | |
1636 | * On the first callout to FUSE server, inarg->in_size and | |
1637 | * inarg->out_size will be NULL; then, the server completes the ioctl | |
1638 | * with FUSE_IOCTL_RETRY set in out->flags, out->in_iovs set to 1 and | |
1639 | * the actual iov array to | |
1640 | * | |
1641 | * { { .iov_base = inarg.arg, .iov_len = sizeof(struct a) } } | |
1642 | * | |
1643 | * which tells FUSE to copy in the requested area and retry the ioctl. | |
1644 | * On the second round, the server has access to the structure and | |
1645 | * from that it can tell what to look for next, so on the invocation, | |
1646 | * it sets FUSE_IOCTL_RETRY, out->in_iovs to 2 and iov array to | |
1647 | * | |
1648 | * { { .iov_base = inarg.arg, .iov_len = sizeof(struct a) }, | |
1649 | * { .iov_base = a.buf, .iov_len = a.buflen } } | |
1650 | * | |
1651 | * FUSE will copy both struct a and the pointed buffer from the | |
1652 | * process doing the ioctl and retry ioctl with both struct a and the | |
1653 | * buffer. | |
1654 | * | |
1655 | * This time, FUSE server has everything it needs and completes ioctl | |
1656 | * without FUSE_IOCTL_RETRY which finishes the ioctl call. | |
1657 | * | |
1658 | * Copying data out works the same way. | |
1659 | * | |
1660 | * Note that if FUSE_IOCTL_UNRESTRICTED is clear, the kernel | |
1661 | * automatically initializes in and out iovs by decoding @cmd with | |
1662 | * _IOC_* macros and the server is not allowed to request RETRY. This | |
1663 | * limits ioctl data transfers to well-formed ioctls and is the forced | |
1664 | * behavior for all FUSE servers. | |
1665 | */ | |
08cbf542 TH |
1666 | long fuse_do_ioctl(struct file *file, unsigned int cmd, unsigned long arg, |
1667 | unsigned int flags) | |
59efec7b | 1668 | { |
59efec7b | 1669 | struct fuse_file *ff = file->private_data; |
d36f2487 | 1670 | struct fuse_conn *fc = ff->fc; |
59efec7b TH |
1671 | struct fuse_ioctl_in inarg = { |
1672 | .fh = ff->fh, | |
1673 | .cmd = cmd, | |
1674 | .arg = arg, | |
1675 | .flags = flags | |
1676 | }; | |
1677 | struct fuse_ioctl_out outarg; | |
1678 | struct fuse_req *req = NULL; | |
1679 | struct page **pages = NULL; | |
1680 | struct page *iov_page = NULL; | |
1681 | struct iovec *in_iov = NULL, *out_iov = NULL; | |
1682 | unsigned int in_iovs = 0, out_iovs = 0, num_pages = 0, max_pages; | |
1683 | size_t in_size, out_size, transferred; | |
1684 | int err; | |
1685 | ||
1686 | /* assume all the iovs returned by client always fits in a page */ | |
1687 | BUILD_BUG_ON(sizeof(struct iovec) * FUSE_IOCTL_MAX_IOV > PAGE_SIZE); | |
1688 | ||
59efec7b TH |
1689 | err = -ENOMEM; |
1690 | pages = kzalloc(sizeof(pages[0]) * FUSE_MAX_PAGES_PER_REQ, GFP_KERNEL); | |
1691 | iov_page = alloc_page(GFP_KERNEL); | |
1692 | if (!pages || !iov_page) | |
1693 | goto out; | |
1694 | ||
1695 | /* | |
1696 | * If restricted, initialize IO parameters as encoded in @cmd. | |
1697 | * RETRY from server is not allowed. | |
1698 | */ | |
1699 | if (!(flags & FUSE_IOCTL_UNRESTRICTED)) { | |
1700 | struct iovec *iov = page_address(iov_page); | |
1701 | ||
c9f0523d | 1702 | iov->iov_base = (void __user *)arg; |
59efec7b TH |
1703 | iov->iov_len = _IOC_SIZE(cmd); |
1704 | ||
1705 | if (_IOC_DIR(cmd) & _IOC_WRITE) { | |
1706 | in_iov = iov; | |
1707 | in_iovs = 1; | |
1708 | } | |
1709 | ||
1710 | if (_IOC_DIR(cmd) & _IOC_READ) { | |
1711 | out_iov = iov; | |
1712 | out_iovs = 1; | |
1713 | } | |
1714 | } | |
1715 | ||
1716 | retry: | |
1717 | inarg.in_size = in_size = iov_length(in_iov, in_iovs); | |
1718 | inarg.out_size = out_size = iov_length(out_iov, out_iovs); | |
1719 | ||
1720 | /* | |
1721 | * Out data can be used either for actual out data or iovs, | |
1722 | * make sure there always is at least one page. | |
1723 | */ | |
1724 | out_size = max_t(size_t, out_size, PAGE_SIZE); | |
1725 | max_pages = DIV_ROUND_UP(max(in_size, out_size), PAGE_SIZE); | |
1726 | ||
1727 | /* make sure there are enough buffer pages and init request with them */ | |
1728 | err = -ENOMEM; | |
1729 | if (max_pages > FUSE_MAX_PAGES_PER_REQ) | |
1730 | goto out; | |
1731 | while (num_pages < max_pages) { | |
1732 | pages[num_pages] = alloc_page(GFP_KERNEL | __GFP_HIGHMEM); | |
1733 | if (!pages[num_pages]) | |
1734 | goto out; | |
1735 | num_pages++; | |
1736 | } | |
1737 | ||
1738 | req = fuse_get_req(fc); | |
1739 | if (IS_ERR(req)) { | |
1740 | err = PTR_ERR(req); | |
1741 | req = NULL; | |
1742 | goto out; | |
1743 | } | |
1744 | memcpy(req->pages, pages, sizeof(req->pages[0]) * num_pages); | |
1745 | req->num_pages = num_pages; | |
1746 | ||
1747 | /* okay, let's send it to the client */ | |
1748 | req->in.h.opcode = FUSE_IOCTL; | |
d36f2487 | 1749 | req->in.h.nodeid = ff->nodeid; |
59efec7b TH |
1750 | req->in.numargs = 1; |
1751 | req->in.args[0].size = sizeof(inarg); | |
1752 | req->in.args[0].value = &inarg; | |
1753 | if (in_size) { | |
1754 | req->in.numargs++; | |
1755 | req->in.args[1].size = in_size; | |
1756 | req->in.argpages = 1; | |
1757 | ||
1758 | err = fuse_ioctl_copy_user(pages, in_iov, in_iovs, in_size, | |
1759 | false); | |
1760 | if (err) | |
1761 | goto out; | |
1762 | } | |
1763 | ||
1764 | req->out.numargs = 2; | |
1765 | req->out.args[0].size = sizeof(outarg); | |
1766 | req->out.args[0].value = &outarg; | |
1767 | req->out.args[1].size = out_size; | |
1768 | req->out.argpages = 1; | |
1769 | req->out.argvar = 1; | |
1770 | ||
b93f858a | 1771 | fuse_request_send(fc, req); |
59efec7b TH |
1772 | err = req->out.h.error; |
1773 | transferred = req->out.args[1].size; | |
1774 | fuse_put_request(fc, req); | |
1775 | req = NULL; | |
1776 | if (err) | |
1777 | goto out; | |
1778 | ||
1779 | /* did it ask for retry? */ | |
1780 | if (outarg.flags & FUSE_IOCTL_RETRY) { | |
1781 | char *vaddr; | |
1782 | ||
1783 | /* no retry if in restricted mode */ | |
1784 | err = -EIO; | |
1785 | if (!(flags & FUSE_IOCTL_UNRESTRICTED)) | |
1786 | goto out; | |
1787 | ||
1788 | in_iovs = outarg.in_iovs; | |
1789 | out_iovs = outarg.out_iovs; | |
1790 | ||
1791 | /* | |
1792 | * Make sure things are in boundary, separate checks | |
1793 | * are to protect against overflow. | |
1794 | */ | |
1795 | err = -ENOMEM; | |
1796 | if (in_iovs > FUSE_IOCTL_MAX_IOV || | |
1797 | out_iovs > FUSE_IOCTL_MAX_IOV || | |
1798 | in_iovs + out_iovs > FUSE_IOCTL_MAX_IOV) | |
1799 | goto out; | |
1800 | ||
1801 | err = -EIO; | |
1802 | if ((in_iovs + out_iovs) * sizeof(struct iovec) != transferred) | |
1803 | goto out; | |
1804 | ||
1805 | /* okay, copy in iovs and retry */ | |
1806 | vaddr = kmap_atomic(pages[0], KM_USER0); | |
1807 | memcpy(page_address(iov_page), vaddr, transferred); | |
1808 | kunmap_atomic(vaddr, KM_USER0); | |
1809 | ||
1810 | in_iov = page_address(iov_page); | |
1811 | out_iov = in_iov + in_iovs; | |
1812 | ||
1813 | goto retry; | |
1814 | } | |
1815 | ||
1816 | err = -EIO; | |
1817 | if (transferred > inarg.out_size) | |
1818 | goto out; | |
1819 | ||
1820 | err = fuse_ioctl_copy_user(pages, out_iov, out_iovs, transferred, true); | |
1821 | out: | |
1822 | if (req) | |
1823 | fuse_put_request(fc, req); | |
1824 | if (iov_page) | |
1825 | __free_page(iov_page); | |
1826 | while (num_pages) | |
1827 | __free_page(pages[--num_pages]); | |
1828 | kfree(pages); | |
1829 | ||
1830 | return err ? err : outarg.result; | |
1831 | } | |
08cbf542 | 1832 | EXPORT_SYMBOL_GPL(fuse_do_ioctl); |
59efec7b | 1833 | |
d36f2487 MS |
1834 | static long fuse_file_ioctl_common(struct file *file, unsigned int cmd, |
1835 | unsigned long arg, unsigned int flags) | |
1836 | { | |
1837 | struct inode *inode = file->f_dentry->d_inode; | |
1838 | struct fuse_conn *fc = get_fuse_conn(inode); | |
1839 | ||
1840 | if (!fuse_allow_task(fc, current)) | |
1841 | return -EACCES; | |
1842 | ||
1843 | if (is_bad_inode(inode)) | |
1844 | return -EIO; | |
1845 | ||
1846 | return fuse_do_ioctl(file, cmd, arg, flags); | |
1847 | } | |
1848 | ||
59efec7b TH |
1849 | static long fuse_file_ioctl(struct file *file, unsigned int cmd, |
1850 | unsigned long arg) | |
1851 | { | |
d36f2487 | 1852 | return fuse_file_ioctl_common(file, cmd, arg, 0); |
59efec7b TH |
1853 | } |
1854 | ||
1855 | static long fuse_file_compat_ioctl(struct file *file, unsigned int cmd, | |
1856 | unsigned long arg) | |
1857 | { | |
d36f2487 | 1858 | return fuse_file_ioctl_common(file, cmd, arg, FUSE_IOCTL_COMPAT); |
59efec7b TH |
1859 | } |
1860 | ||
95668a69 TH |
1861 | /* |
1862 | * All files which have been polled are linked to RB tree | |
1863 | * fuse_conn->polled_files which is indexed by kh. Walk the tree and | |
1864 | * find the matching one. | |
1865 | */ | |
1866 | static struct rb_node **fuse_find_polled_node(struct fuse_conn *fc, u64 kh, | |
1867 | struct rb_node **parent_out) | |
1868 | { | |
1869 | struct rb_node **link = &fc->polled_files.rb_node; | |
1870 | struct rb_node *last = NULL; | |
1871 | ||
1872 | while (*link) { | |
1873 | struct fuse_file *ff; | |
1874 | ||
1875 | last = *link; | |
1876 | ff = rb_entry(last, struct fuse_file, polled_node); | |
1877 | ||
1878 | if (kh < ff->kh) | |
1879 | link = &last->rb_left; | |
1880 | else if (kh > ff->kh) | |
1881 | link = &last->rb_right; | |
1882 | else | |
1883 | return link; | |
1884 | } | |
1885 | ||
1886 | if (parent_out) | |
1887 | *parent_out = last; | |
1888 | return link; | |
1889 | } | |
1890 | ||
1891 | /* | |
1892 | * The file is about to be polled. Make sure it's on the polled_files | |
1893 | * RB tree. Note that files once added to the polled_files tree are | |
1894 | * not removed before the file is released. This is because a file | |
1895 | * polled once is likely to be polled again. | |
1896 | */ | |
1897 | static void fuse_register_polled_file(struct fuse_conn *fc, | |
1898 | struct fuse_file *ff) | |
1899 | { | |
1900 | spin_lock(&fc->lock); | |
1901 | if (RB_EMPTY_NODE(&ff->polled_node)) { | |
1902 | struct rb_node **link, *parent; | |
1903 | ||
1904 | link = fuse_find_polled_node(fc, ff->kh, &parent); | |
1905 | BUG_ON(*link); | |
1906 | rb_link_node(&ff->polled_node, parent, link); | |
1907 | rb_insert_color(&ff->polled_node, &fc->polled_files); | |
1908 | } | |
1909 | spin_unlock(&fc->lock); | |
1910 | } | |
1911 | ||
08cbf542 | 1912 | unsigned fuse_file_poll(struct file *file, poll_table *wait) |
95668a69 | 1913 | { |
95668a69 | 1914 | struct fuse_file *ff = file->private_data; |
797759aa | 1915 | struct fuse_conn *fc = ff->fc; |
95668a69 TH |
1916 | struct fuse_poll_in inarg = { .fh = ff->fh, .kh = ff->kh }; |
1917 | struct fuse_poll_out outarg; | |
1918 | struct fuse_req *req; | |
1919 | int err; | |
1920 | ||
1921 | if (fc->no_poll) | |
1922 | return DEFAULT_POLLMASK; | |
1923 | ||
1924 | poll_wait(file, &ff->poll_wait, wait); | |
1925 | ||
1926 | /* | |
1927 | * Ask for notification iff there's someone waiting for it. | |
1928 | * The client may ignore the flag and always notify. | |
1929 | */ | |
1930 | if (waitqueue_active(&ff->poll_wait)) { | |
1931 | inarg.flags |= FUSE_POLL_SCHEDULE_NOTIFY; | |
1932 | fuse_register_polled_file(fc, ff); | |
1933 | } | |
1934 | ||
1935 | req = fuse_get_req(fc); | |
1936 | if (IS_ERR(req)) | |
201fa69a | 1937 | return POLLERR; |
95668a69 TH |
1938 | |
1939 | req->in.h.opcode = FUSE_POLL; | |
797759aa | 1940 | req->in.h.nodeid = ff->nodeid; |
95668a69 TH |
1941 | req->in.numargs = 1; |
1942 | req->in.args[0].size = sizeof(inarg); | |
1943 | req->in.args[0].value = &inarg; | |
1944 | req->out.numargs = 1; | |
1945 | req->out.args[0].size = sizeof(outarg); | |
1946 | req->out.args[0].value = &outarg; | |
b93f858a | 1947 | fuse_request_send(fc, req); |
95668a69 TH |
1948 | err = req->out.h.error; |
1949 | fuse_put_request(fc, req); | |
1950 | ||
1951 | if (!err) | |
1952 | return outarg.revents; | |
1953 | if (err == -ENOSYS) { | |
1954 | fc->no_poll = 1; | |
1955 | return DEFAULT_POLLMASK; | |
1956 | } | |
1957 | return POLLERR; | |
1958 | } | |
08cbf542 | 1959 | EXPORT_SYMBOL_GPL(fuse_file_poll); |
95668a69 TH |
1960 | |
1961 | /* | |
1962 | * This is called from fuse_handle_notify() on FUSE_NOTIFY_POLL and | |
1963 | * wakes up the poll waiters. | |
1964 | */ | |
1965 | int fuse_notify_poll_wakeup(struct fuse_conn *fc, | |
1966 | struct fuse_notify_poll_wakeup_out *outarg) | |
1967 | { | |
1968 | u64 kh = outarg->kh; | |
1969 | struct rb_node **link; | |
1970 | ||
1971 | spin_lock(&fc->lock); | |
1972 | ||
1973 | link = fuse_find_polled_node(fc, kh, NULL); | |
1974 | if (*link) { | |
1975 | struct fuse_file *ff; | |
1976 | ||
1977 | ff = rb_entry(*link, struct fuse_file, polled_node); | |
1978 | wake_up_interruptible_sync(&ff->poll_wait); | |
1979 | } | |
1980 | ||
1981 | spin_unlock(&fc->lock); | |
1982 | return 0; | |
1983 | } | |
1984 | ||
4b6f5d20 | 1985 | static const struct file_operations fuse_file_operations = { |
5559b8f4 | 1986 | .llseek = fuse_file_llseek, |
543ade1f | 1987 | .read = do_sync_read, |
bcb4be80 | 1988 | .aio_read = fuse_file_aio_read, |
543ade1f | 1989 | .write = do_sync_write, |
ea9b9907 | 1990 | .aio_write = fuse_file_aio_write, |
b6aeaded MS |
1991 | .mmap = fuse_file_mmap, |
1992 | .open = fuse_open, | |
1993 | .flush = fuse_flush, | |
1994 | .release = fuse_release, | |
1995 | .fsync = fuse_fsync, | |
71421259 | 1996 | .lock = fuse_file_lock, |
a9ff4f87 | 1997 | .flock = fuse_file_flock, |
5ffc4ef4 | 1998 | .splice_read = generic_file_splice_read, |
59efec7b TH |
1999 | .unlocked_ioctl = fuse_file_ioctl, |
2000 | .compat_ioctl = fuse_file_compat_ioctl, | |
95668a69 | 2001 | .poll = fuse_file_poll, |
b6aeaded MS |
2002 | }; |
2003 | ||
4b6f5d20 | 2004 | static const struct file_operations fuse_direct_io_file_operations = { |
5559b8f4 | 2005 | .llseek = fuse_file_llseek, |
413ef8cb MS |
2006 | .read = fuse_direct_read, |
2007 | .write = fuse_direct_write, | |
fc280c96 | 2008 | .mmap = fuse_direct_mmap, |
413ef8cb MS |
2009 | .open = fuse_open, |
2010 | .flush = fuse_flush, | |
2011 | .release = fuse_release, | |
2012 | .fsync = fuse_fsync, | |
71421259 | 2013 | .lock = fuse_file_lock, |
a9ff4f87 | 2014 | .flock = fuse_file_flock, |
59efec7b TH |
2015 | .unlocked_ioctl = fuse_file_ioctl, |
2016 | .compat_ioctl = fuse_file_compat_ioctl, | |
95668a69 | 2017 | .poll = fuse_file_poll, |
fc280c96 | 2018 | /* no splice_read */ |
413ef8cb MS |
2019 | }; |
2020 | ||
f5e54d6e | 2021 | static const struct address_space_operations fuse_file_aops = { |
b6aeaded | 2022 | .readpage = fuse_readpage, |
3be5a52b MS |
2023 | .writepage = fuse_writepage, |
2024 | .launder_page = fuse_launder_page, | |
5e6f58a1 NP |
2025 | .write_begin = fuse_write_begin, |
2026 | .write_end = fuse_write_end, | |
db50b96c | 2027 | .readpages = fuse_readpages, |
3be5a52b | 2028 | .set_page_dirty = __set_page_dirty_nobuffers, |
b2d2272f | 2029 | .bmap = fuse_bmap, |
b6aeaded MS |
2030 | }; |
2031 | ||
2032 | void fuse_init_file_inode(struct inode *inode) | |
2033 | { | |
45323fb7 MS |
2034 | inode->i_fop = &fuse_file_operations; |
2035 | inode->i_data.a_ops = &fuse_file_aops; | |
b6aeaded | 2036 | } |