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> |
b6aeaded | 15 | |
4b6f5d20 | 16 | static const struct file_operations fuse_direct_io_file_operations; |
45323fb7 | 17 | |
fd72faac MS |
18 | static int fuse_send_open(struct inode *inode, struct file *file, int isdir, |
19 | struct fuse_open_out *outargp) | |
b6aeaded MS |
20 | { |
21 | struct fuse_conn *fc = get_fuse_conn(inode); | |
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; | |
fd72faac MS |
34 | req->in.h.opcode = isdir ? FUSE_OPENDIR : FUSE_OPEN; |
35 | req->in.h.nodeid = get_node_id(inode); | |
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; | |
52 | ff = kmalloc(sizeof(struct fuse_file), GFP_KERNEL); | |
53 | if (ff) { | |
33649c91 MS |
54 | ff->reserved_req = fuse_request_alloc(); |
55 | if (!ff->reserved_req) { | |
fd72faac | 56 | kfree(ff); |
bb875b38 | 57 | return NULL; |
8744969a AB |
58 | } else { |
59 | INIT_LIST_HEAD(&ff->write_entry); | |
60 | atomic_set(&ff->count, 0); | |
acf99433 TH |
61 | spin_lock(&fc->lock); |
62 | ff->kh = ++fc->khctr; | |
63 | spin_unlock(&fc->lock); | |
fd72faac | 64 | } |
95668a69 TH |
65 | RB_CLEAR_NODE(&ff->polled_node); |
66 | init_waitqueue_head(&ff->poll_wait); | |
fd72faac MS |
67 | } |
68 | return ff; | |
69 | } | |
70 | ||
71 | void fuse_file_free(struct fuse_file *ff) | |
72 | { | |
33649c91 | 73 | fuse_request_free(ff->reserved_req); |
fd72faac MS |
74 | kfree(ff); |
75 | } | |
76 | ||
c756e0a4 MS |
77 | static struct fuse_file *fuse_file_get(struct fuse_file *ff) |
78 | { | |
79 | atomic_inc(&ff->count); | |
80 | return ff; | |
81 | } | |
82 | ||
819c4b3b MS |
83 | static void fuse_release_end(struct fuse_conn *fc, struct fuse_req *req) |
84 | { | |
b57d4264 MS |
85 | dput(req->misc.release.dentry); |
86 | mntput(req->misc.release.vfsmount); | |
819c4b3b MS |
87 | } |
88 | ||
c756e0a4 MS |
89 | static void fuse_file_put(struct fuse_file *ff) |
90 | { | |
91 | if (atomic_dec_and_test(&ff->count)) { | |
92 | struct fuse_req *req = ff->reserved_req; | |
b57d4264 MS |
93 | struct inode *inode = req->misc.release.dentry->d_inode; |
94 | struct fuse_conn *fc = get_fuse_conn(inode); | |
819c4b3b | 95 | req->end = fuse_release_end; |
b93f858a | 96 | fuse_request_send_background(fc, req); |
c756e0a4 MS |
97 | kfree(ff); |
98 | } | |
99 | } | |
100 | ||
fd72faac MS |
101 | void fuse_finish_open(struct inode *inode, struct file *file, |
102 | struct fuse_file *ff, struct fuse_open_out *outarg) | |
103 | { | |
104 | if (outarg->open_flags & FOPEN_DIRECT_IO) | |
105 | file->f_op = &fuse_direct_io_file_operations; | |
106 | if (!(outarg->open_flags & FOPEN_KEEP_CACHE)) | |
b1009979 | 107 | invalidate_inode_pages2(inode->i_mapping); |
a7c1b990 TH |
108 | if (outarg->open_flags & FOPEN_NONSEEKABLE) |
109 | nonseekable_open(inode, file); | |
fd72faac | 110 | ff->fh = outarg->fh; |
c756e0a4 | 111 | file->private_data = fuse_file_get(ff); |
fd72faac MS |
112 | } |
113 | ||
114 | int fuse_open_common(struct inode *inode, struct file *file, int isdir) | |
115 | { | |
acf99433 | 116 | struct fuse_conn *fc = get_fuse_conn(inode); |
b6aeaded MS |
117 | struct fuse_open_out outarg; |
118 | struct fuse_file *ff; | |
119 | int err; | |
b6aeaded | 120 | |
dd190d06 MS |
121 | /* VFS checks this, but only _after_ ->open() */ |
122 | if (file->f_flags & O_DIRECT) | |
123 | return -EINVAL; | |
124 | ||
b6aeaded MS |
125 | err = generic_file_open(inode, file); |
126 | if (err) | |
127 | return err; | |
128 | ||
acf99433 | 129 | ff = fuse_file_alloc(fc); |
b6aeaded | 130 | if (!ff) |
fd72faac | 131 | return -ENOMEM; |
b6aeaded | 132 | |
fd72faac MS |
133 | err = fuse_send_open(inode, file, isdir, &outarg); |
134 | if (err) | |
135 | fuse_file_free(ff); | |
136 | else { | |
137 | if (isdir) | |
138 | outarg.open_flags &= ~FOPEN_DIRECT_IO; | |
139 | fuse_finish_open(inode, file, ff, &outarg); | |
b6aeaded MS |
140 | } |
141 | ||
b6aeaded MS |
142 | return err; |
143 | } | |
144 | ||
c756e0a4 | 145 | void fuse_release_fill(struct fuse_file *ff, u64 nodeid, int flags, int opcode) |
64c6d8ed | 146 | { |
33649c91 | 147 | struct fuse_req *req = ff->reserved_req; |
b57d4264 | 148 | struct fuse_release_in *inarg = &req->misc.release.in; |
b6aeaded MS |
149 | |
150 | inarg->fh = ff->fh; | |
fd72faac | 151 | inarg->flags = flags; |
51eb01e7 | 152 | req->in.h.opcode = opcode; |
fd72faac | 153 | req->in.h.nodeid = nodeid; |
b6aeaded MS |
154 | req->in.numargs = 1; |
155 | req->in.args[0].size = sizeof(struct fuse_release_in); | |
156 | req->in.args[0].value = inarg; | |
fd72faac MS |
157 | } |
158 | ||
159 | int fuse_release_common(struct inode *inode, struct file *file, int isdir) | |
160 | { | |
161 | struct fuse_file *ff = file->private_data; | |
162 | if (ff) { | |
93a8c3cd | 163 | struct fuse_conn *fc = get_fuse_conn(inode); |
b57d4264 | 164 | struct fuse_req *req = ff->reserved_req; |
93a8c3cd | 165 | |
c756e0a4 MS |
166 | fuse_release_fill(ff, get_node_id(inode), file->f_flags, |
167 | isdir ? FUSE_RELEASEDIR : FUSE_RELEASE); | |
51eb01e7 MS |
168 | |
169 | /* Hold vfsmount and dentry until release is finished */ | |
b57d4264 MS |
170 | req->misc.release.vfsmount = mntget(file->f_path.mnt); |
171 | req->misc.release.dentry = dget(file->f_path.dentry); | |
93a8c3cd MS |
172 | |
173 | spin_lock(&fc->lock); | |
174 | list_del(&ff->write_entry); | |
95668a69 TH |
175 | if (!RB_EMPTY_NODE(&ff->polled_node)) |
176 | rb_erase(&ff->polled_node, &fc->polled_files); | |
93a8c3cd | 177 | spin_unlock(&fc->lock); |
95668a69 TH |
178 | |
179 | wake_up_interruptible_sync(&ff->poll_wait); | |
c756e0a4 MS |
180 | /* |
181 | * Normally this will send the RELEASE request, | |
182 | * however if some asynchronous READ or WRITE requests | |
183 | * are outstanding, the sending will be delayed | |
184 | */ | |
185 | fuse_file_put(ff); | |
fd72faac | 186 | } |
b6aeaded MS |
187 | |
188 | /* Return value is ignored by VFS */ | |
189 | return 0; | |
190 | } | |
191 | ||
04730fef MS |
192 | static int fuse_open(struct inode *inode, struct file *file) |
193 | { | |
194 | return fuse_open_common(inode, file, 0); | |
195 | } | |
196 | ||
197 | static int fuse_release(struct inode *inode, struct file *file) | |
198 | { | |
199 | return fuse_release_common(inode, file, 0); | |
200 | } | |
201 | ||
71421259 | 202 | /* |
9c8ef561 MS |
203 | * Scramble the ID space with XTEA, so that the value of the files_struct |
204 | * pointer is not exposed to userspace. | |
71421259 | 205 | */ |
f3332114 | 206 | u64 fuse_lock_owner_id(struct fuse_conn *fc, fl_owner_t id) |
71421259 | 207 | { |
9c8ef561 MS |
208 | u32 *k = fc->scramble_key; |
209 | u64 v = (unsigned long) id; | |
210 | u32 v0 = v; | |
211 | u32 v1 = v >> 32; | |
212 | u32 sum = 0; | |
213 | int i; | |
214 | ||
215 | for (i = 0; i < 32; i++) { | |
216 | v0 += ((v1 << 4 ^ v1 >> 5) + v1) ^ (sum + k[sum & 3]); | |
217 | sum += 0x9E3779B9; | |
218 | v1 += ((v0 << 4 ^ v0 >> 5) + v0) ^ (sum + k[sum>>11 & 3]); | |
219 | } | |
220 | ||
221 | return (u64) v0 + ((u64) v1 << 32); | |
71421259 MS |
222 | } |
223 | ||
3be5a52b MS |
224 | /* |
225 | * Check if page is under writeback | |
226 | * | |
227 | * This is currently done by walking the list of writepage requests | |
228 | * for the inode, which can be pretty inefficient. | |
229 | */ | |
230 | static bool fuse_page_is_writeback(struct inode *inode, pgoff_t index) | |
231 | { | |
232 | struct fuse_conn *fc = get_fuse_conn(inode); | |
233 | struct fuse_inode *fi = get_fuse_inode(inode); | |
234 | struct fuse_req *req; | |
235 | bool found = false; | |
236 | ||
237 | spin_lock(&fc->lock); | |
238 | list_for_each_entry(req, &fi->writepages, writepages_entry) { | |
239 | pgoff_t curr_index; | |
240 | ||
241 | BUG_ON(req->inode != inode); | |
242 | curr_index = req->misc.write.in.offset >> PAGE_CACHE_SHIFT; | |
243 | if (curr_index == index) { | |
244 | found = true; | |
245 | break; | |
246 | } | |
247 | } | |
248 | spin_unlock(&fc->lock); | |
249 | ||
250 | return found; | |
251 | } | |
252 | ||
253 | /* | |
254 | * Wait for page writeback to be completed. | |
255 | * | |
256 | * Since fuse doesn't rely on the VM writeback tracking, this has to | |
257 | * use some other means. | |
258 | */ | |
259 | static int fuse_wait_on_page_writeback(struct inode *inode, pgoff_t index) | |
260 | { | |
261 | struct fuse_inode *fi = get_fuse_inode(inode); | |
262 | ||
263 | wait_event(fi->page_waitq, !fuse_page_is_writeback(inode, index)); | |
264 | return 0; | |
265 | } | |
266 | ||
75e1fcc0 | 267 | static int fuse_flush(struct file *file, fl_owner_t id) |
b6aeaded | 268 | { |
7706a9d6 | 269 | struct inode *inode = file->f_path.dentry->d_inode; |
b6aeaded MS |
270 | struct fuse_conn *fc = get_fuse_conn(inode); |
271 | struct fuse_file *ff = file->private_data; | |
272 | struct fuse_req *req; | |
273 | struct fuse_flush_in inarg; | |
274 | int err; | |
275 | ||
248d86e8 MS |
276 | if (is_bad_inode(inode)) |
277 | return -EIO; | |
278 | ||
b6aeaded MS |
279 | if (fc->no_flush) |
280 | return 0; | |
281 | ||
33649c91 | 282 | req = fuse_get_req_nofail(fc, file); |
b6aeaded MS |
283 | memset(&inarg, 0, sizeof(inarg)); |
284 | inarg.fh = ff->fh; | |
9c8ef561 | 285 | inarg.lock_owner = fuse_lock_owner_id(fc, id); |
b6aeaded MS |
286 | req->in.h.opcode = FUSE_FLUSH; |
287 | req->in.h.nodeid = get_node_id(inode); | |
b6aeaded MS |
288 | req->in.numargs = 1; |
289 | req->in.args[0].size = sizeof(inarg); | |
290 | req->in.args[0].value = &inarg; | |
71421259 | 291 | req->force = 1; |
b93f858a | 292 | fuse_request_send(fc, req); |
b6aeaded MS |
293 | err = req->out.h.error; |
294 | fuse_put_request(fc, req); | |
295 | if (err == -ENOSYS) { | |
296 | fc->no_flush = 1; | |
297 | err = 0; | |
298 | } | |
299 | return err; | |
300 | } | |
301 | ||
3be5a52b MS |
302 | /* |
303 | * Wait for all pending writepages on the inode to finish. | |
304 | * | |
305 | * This is currently done by blocking further writes with FUSE_NOWRITE | |
306 | * and waiting for all sent writes to complete. | |
307 | * | |
308 | * This must be called under i_mutex, otherwise the FUSE_NOWRITE usage | |
309 | * could conflict with truncation. | |
310 | */ | |
311 | static void fuse_sync_writes(struct inode *inode) | |
312 | { | |
313 | fuse_set_nowrite(inode); | |
314 | fuse_release_nowrite(inode); | |
315 | } | |
316 | ||
82547981 MS |
317 | int fuse_fsync_common(struct file *file, struct dentry *de, int datasync, |
318 | int isdir) | |
b6aeaded MS |
319 | { |
320 | struct inode *inode = de->d_inode; | |
321 | struct fuse_conn *fc = get_fuse_conn(inode); | |
322 | struct fuse_file *ff = file->private_data; | |
323 | struct fuse_req *req; | |
324 | struct fuse_fsync_in inarg; | |
325 | int err; | |
326 | ||
248d86e8 MS |
327 | if (is_bad_inode(inode)) |
328 | return -EIO; | |
329 | ||
82547981 | 330 | if ((!isdir && fc->no_fsync) || (isdir && fc->no_fsyncdir)) |
b6aeaded MS |
331 | return 0; |
332 | ||
3be5a52b MS |
333 | /* |
334 | * Start writeback against all dirty pages of the inode, then | |
335 | * wait for all outstanding writes, before sending the FSYNC | |
336 | * request. | |
337 | */ | |
338 | err = write_inode_now(inode, 0); | |
339 | if (err) | |
340 | return err; | |
341 | ||
342 | fuse_sync_writes(inode); | |
343 | ||
ce1d5a49 MS |
344 | req = fuse_get_req(fc); |
345 | if (IS_ERR(req)) | |
346 | return PTR_ERR(req); | |
b6aeaded MS |
347 | |
348 | memset(&inarg, 0, sizeof(inarg)); | |
349 | inarg.fh = ff->fh; | |
350 | inarg.fsync_flags = datasync ? 1 : 0; | |
82547981 | 351 | req->in.h.opcode = isdir ? FUSE_FSYNCDIR : FUSE_FSYNC; |
b6aeaded | 352 | req->in.h.nodeid = get_node_id(inode); |
b6aeaded MS |
353 | req->in.numargs = 1; |
354 | req->in.args[0].size = sizeof(inarg); | |
355 | req->in.args[0].value = &inarg; | |
b93f858a | 356 | fuse_request_send(fc, req); |
b6aeaded MS |
357 | err = req->out.h.error; |
358 | fuse_put_request(fc, req); | |
359 | if (err == -ENOSYS) { | |
82547981 MS |
360 | if (isdir) |
361 | fc->no_fsyncdir = 1; | |
362 | else | |
363 | fc->no_fsync = 1; | |
b6aeaded MS |
364 | err = 0; |
365 | } | |
366 | return err; | |
367 | } | |
368 | ||
82547981 MS |
369 | static int fuse_fsync(struct file *file, struct dentry *de, int datasync) |
370 | { | |
371 | return fuse_fsync_common(file, de, datasync, 0); | |
372 | } | |
373 | ||
a6643094 | 374 | void fuse_read_fill(struct fuse_req *req, struct file *file, |
361b1eb5 | 375 | struct inode *inode, loff_t pos, size_t count, int opcode) |
b6aeaded | 376 | { |
5c5c5e51 | 377 | struct fuse_read_in *inarg = &req->misc.read.in; |
a6643094 | 378 | struct fuse_file *ff = file->private_data; |
b6aeaded | 379 | |
361b1eb5 MS |
380 | inarg->fh = ff->fh; |
381 | inarg->offset = pos; | |
382 | inarg->size = count; | |
a6643094 | 383 | inarg->flags = file->f_flags; |
361b1eb5 | 384 | req->in.h.opcode = opcode; |
b6aeaded | 385 | req->in.h.nodeid = get_node_id(inode); |
b6aeaded MS |
386 | req->in.numargs = 1; |
387 | req->in.args[0].size = sizeof(struct fuse_read_in); | |
c1aa96a5 | 388 | req->in.args[0].value = inarg; |
b6aeaded MS |
389 | req->out.argvar = 1; |
390 | req->out.numargs = 1; | |
391 | req->out.args[0].size = count; | |
b6aeaded MS |
392 | } |
393 | ||
8bfc016d | 394 | static size_t fuse_send_read(struct fuse_req *req, struct file *file, |
f3332114 MS |
395 | struct inode *inode, loff_t pos, size_t count, |
396 | fl_owner_t owner) | |
04730fef | 397 | { |
361b1eb5 | 398 | struct fuse_conn *fc = get_fuse_conn(inode); |
f3332114 | 399 | |
a6643094 | 400 | fuse_read_fill(req, file, inode, pos, count, FUSE_READ); |
f3332114 | 401 | if (owner != NULL) { |
5c5c5e51 | 402 | struct fuse_read_in *inarg = &req->misc.read.in; |
f3332114 MS |
403 | |
404 | inarg->read_flags |= FUSE_READ_LOCKOWNER; | |
405 | inarg->lock_owner = fuse_lock_owner_id(fc, owner); | |
406 | } | |
b93f858a | 407 | fuse_request_send(fc, req); |
361b1eb5 | 408 | return req->out.args[0].size; |
04730fef MS |
409 | } |
410 | ||
5c5c5e51 MS |
411 | static void fuse_read_update_size(struct inode *inode, loff_t size, |
412 | u64 attr_ver) | |
413 | { | |
414 | struct fuse_conn *fc = get_fuse_conn(inode); | |
415 | struct fuse_inode *fi = get_fuse_inode(inode); | |
416 | ||
417 | spin_lock(&fc->lock); | |
418 | if (attr_ver == fi->attr_version && size < inode->i_size) { | |
419 | fi->attr_version = ++fc->attr_version; | |
420 | i_size_write(inode, size); | |
421 | } | |
422 | spin_unlock(&fc->lock); | |
423 | } | |
424 | ||
b6aeaded MS |
425 | static int fuse_readpage(struct file *file, struct page *page) |
426 | { | |
427 | struct inode *inode = page->mapping->host; | |
428 | struct fuse_conn *fc = get_fuse_conn(inode); | |
248d86e8 | 429 | struct fuse_req *req; |
5c5c5e51 MS |
430 | size_t num_read; |
431 | loff_t pos = page_offset(page); | |
432 | size_t count = PAGE_CACHE_SIZE; | |
433 | u64 attr_ver; | |
248d86e8 MS |
434 | int err; |
435 | ||
436 | err = -EIO; | |
437 | if (is_bad_inode(inode)) | |
438 | goto out; | |
439 | ||
3be5a52b MS |
440 | /* |
441 | * Page writeback can extend beyond the liftime of the | |
442 | * page-cache page, so make sure we read a properly synced | |
443 | * page. | |
444 | */ | |
445 | fuse_wait_on_page_writeback(inode, page->index); | |
446 | ||
ce1d5a49 MS |
447 | req = fuse_get_req(fc); |
448 | err = PTR_ERR(req); | |
449 | if (IS_ERR(req)) | |
b6aeaded MS |
450 | goto out; |
451 | ||
5c5c5e51 MS |
452 | attr_ver = fuse_get_attr_version(fc); |
453 | ||
b6aeaded | 454 | req->out.page_zeroing = 1; |
f4975c67 | 455 | req->out.argpages = 1; |
b6aeaded MS |
456 | req->num_pages = 1; |
457 | req->pages[0] = page; | |
5c5c5e51 | 458 | num_read = fuse_send_read(req, file, inode, pos, count, NULL); |
b6aeaded MS |
459 | err = req->out.h.error; |
460 | fuse_put_request(fc, req); | |
5c5c5e51 MS |
461 | |
462 | if (!err) { | |
463 | /* | |
464 | * Short read means EOF. If file size is larger, truncate it | |
465 | */ | |
466 | if (num_read < count) | |
467 | fuse_read_update_size(inode, pos + num_read, attr_ver); | |
468 | ||
b6aeaded | 469 | SetPageUptodate(page); |
5c5c5e51 MS |
470 | } |
471 | ||
b36c31ba | 472 | fuse_invalidate_attr(inode); /* atime changed */ |
b6aeaded MS |
473 | out: |
474 | unlock_page(page); | |
475 | return err; | |
476 | } | |
477 | ||
c1aa96a5 | 478 | static void fuse_readpages_end(struct fuse_conn *fc, struct fuse_req *req) |
db50b96c | 479 | { |
c1aa96a5 | 480 | int i; |
5c5c5e51 MS |
481 | size_t count = req->misc.read.in.size; |
482 | size_t num_read = req->out.args[0].size; | |
483 | struct inode *inode = req->pages[0]->mapping->host; | |
c1aa96a5 | 484 | |
5c5c5e51 MS |
485 | /* |
486 | * Short read means EOF. If file size is larger, truncate it | |
487 | */ | |
488 | if (!req->out.h.error && num_read < count) { | |
489 | loff_t pos = page_offset(req->pages[0]) + num_read; | |
490 | fuse_read_update_size(inode, pos, req->misc.read.attr_ver); | |
491 | } | |
492 | ||
493 | fuse_invalidate_attr(inode); /* atime changed */ | |
c1aa96a5 | 494 | |
db50b96c MS |
495 | for (i = 0; i < req->num_pages; i++) { |
496 | struct page *page = req->pages[i]; | |
497 | if (!req->out.h.error) | |
498 | SetPageUptodate(page); | |
c1aa96a5 MS |
499 | else |
500 | SetPageError(page); | |
db50b96c MS |
501 | unlock_page(page); |
502 | } | |
c756e0a4 MS |
503 | if (req->ff) |
504 | fuse_file_put(req->ff); | |
c1aa96a5 MS |
505 | } |
506 | ||
a6643094 | 507 | static void fuse_send_readpages(struct fuse_req *req, struct file *file, |
c1aa96a5 MS |
508 | struct inode *inode) |
509 | { | |
510 | struct fuse_conn *fc = get_fuse_conn(inode); | |
511 | loff_t pos = page_offset(req->pages[0]); | |
512 | size_t count = req->num_pages << PAGE_CACHE_SHIFT; | |
f4975c67 MS |
513 | |
514 | req->out.argpages = 1; | |
c1aa96a5 | 515 | req->out.page_zeroing = 1; |
a6643094 | 516 | fuse_read_fill(req, file, inode, pos, count, FUSE_READ); |
5c5c5e51 | 517 | req->misc.read.attr_ver = fuse_get_attr_version(fc); |
9cd68455 | 518 | if (fc->async_read) { |
a6643094 | 519 | struct fuse_file *ff = file->private_data; |
c756e0a4 | 520 | req->ff = fuse_file_get(ff); |
9cd68455 | 521 | req->end = fuse_readpages_end; |
b93f858a | 522 | fuse_request_send_background(fc, req); |
9cd68455 | 523 | } else { |
b93f858a | 524 | fuse_request_send(fc, req); |
9cd68455 | 525 | fuse_readpages_end(fc, req); |
e9bb09dd | 526 | fuse_put_request(fc, req); |
9cd68455 | 527 | } |
db50b96c MS |
528 | } |
529 | ||
c756e0a4 | 530 | struct fuse_fill_data { |
db50b96c | 531 | struct fuse_req *req; |
a6643094 | 532 | struct file *file; |
db50b96c MS |
533 | struct inode *inode; |
534 | }; | |
535 | ||
536 | static int fuse_readpages_fill(void *_data, struct page *page) | |
537 | { | |
c756e0a4 | 538 | struct fuse_fill_data *data = _data; |
db50b96c MS |
539 | struct fuse_req *req = data->req; |
540 | struct inode *inode = data->inode; | |
541 | struct fuse_conn *fc = get_fuse_conn(inode); | |
542 | ||
3be5a52b MS |
543 | fuse_wait_on_page_writeback(inode, page->index); |
544 | ||
db50b96c MS |
545 | if (req->num_pages && |
546 | (req->num_pages == FUSE_MAX_PAGES_PER_REQ || | |
547 | (req->num_pages + 1) * PAGE_CACHE_SIZE > fc->max_read || | |
548 | req->pages[req->num_pages - 1]->index + 1 != page->index)) { | |
a6643094 | 549 | fuse_send_readpages(req, data->file, inode); |
ce1d5a49 MS |
550 | data->req = req = fuse_get_req(fc); |
551 | if (IS_ERR(req)) { | |
db50b96c | 552 | unlock_page(page); |
ce1d5a49 | 553 | return PTR_ERR(req); |
db50b96c | 554 | } |
db50b96c MS |
555 | } |
556 | req->pages[req->num_pages] = page; | |
1729a16c | 557 | req->num_pages++; |
db50b96c MS |
558 | return 0; |
559 | } | |
560 | ||
561 | static int fuse_readpages(struct file *file, struct address_space *mapping, | |
562 | struct list_head *pages, unsigned nr_pages) | |
563 | { | |
564 | struct inode *inode = mapping->host; | |
565 | struct fuse_conn *fc = get_fuse_conn(inode); | |
c756e0a4 | 566 | struct fuse_fill_data data; |
db50b96c | 567 | int err; |
248d86e8 | 568 | |
1d7ea732 | 569 | err = -EIO; |
248d86e8 | 570 | if (is_bad_inode(inode)) |
2e990021 | 571 | goto out; |
248d86e8 | 572 | |
a6643094 | 573 | data.file = file; |
db50b96c | 574 | data.inode = inode; |
ce1d5a49 | 575 | data.req = fuse_get_req(fc); |
1d7ea732 | 576 | err = PTR_ERR(data.req); |
ce1d5a49 | 577 | if (IS_ERR(data.req)) |
2e990021 | 578 | goto out; |
db50b96c MS |
579 | |
580 | err = read_cache_pages(mapping, pages, fuse_readpages_fill, &data); | |
d3406ffa MS |
581 | if (!err) { |
582 | if (data.req->num_pages) | |
a6643094 | 583 | fuse_send_readpages(data.req, file, inode); |
d3406ffa MS |
584 | else |
585 | fuse_put_request(fc, data.req); | |
586 | } | |
2e990021 | 587 | out: |
1d7ea732 | 588 | return err; |
db50b96c MS |
589 | } |
590 | ||
bcb4be80 MS |
591 | static ssize_t fuse_file_aio_read(struct kiocb *iocb, const struct iovec *iov, |
592 | unsigned long nr_segs, loff_t pos) | |
593 | { | |
594 | struct inode *inode = iocb->ki_filp->f_mapping->host; | |
595 | ||
596 | if (pos + iov_length(iov, nr_segs) > i_size_read(inode)) { | |
597 | int err; | |
598 | /* | |
599 | * If trying to read past EOF, make sure the i_size | |
600 | * attribute is up-to-date. | |
601 | */ | |
602 | err = fuse_update_attributes(inode, NULL, iocb->ki_filp, NULL); | |
603 | if (err) | |
604 | return err; | |
605 | } | |
606 | ||
607 | return generic_file_aio_read(iocb, iov, nr_segs, pos); | |
608 | } | |
609 | ||
a6643094 | 610 | static void fuse_write_fill(struct fuse_req *req, struct file *file, |
3be5a52b MS |
611 | struct fuse_file *ff, struct inode *inode, |
612 | loff_t pos, size_t count, int writepage) | |
b6aeaded | 613 | { |
f3332114 | 614 | struct fuse_conn *fc = get_fuse_conn(inode); |
b25e82e5 MS |
615 | struct fuse_write_in *inarg = &req->misc.write.in; |
616 | struct fuse_write_out *outarg = &req->misc.write.out; | |
b6aeaded | 617 | |
b25e82e5 MS |
618 | memset(inarg, 0, sizeof(struct fuse_write_in)); |
619 | inarg->fh = ff->fh; | |
620 | inarg->offset = pos; | |
621 | inarg->size = count; | |
622 | inarg->write_flags = writepage ? FUSE_WRITE_CACHE : 0; | |
3be5a52b | 623 | inarg->flags = file ? file->f_flags : 0; |
b6aeaded MS |
624 | req->in.h.opcode = FUSE_WRITE; |
625 | req->in.h.nodeid = get_node_id(inode); | |
b6aeaded | 626 | req->in.numargs = 2; |
f3332114 MS |
627 | if (fc->minor < 9) |
628 | req->in.args[0].size = FUSE_COMPAT_WRITE_IN_SIZE; | |
629 | else | |
630 | req->in.args[0].size = sizeof(struct fuse_write_in); | |
b25e82e5 | 631 | req->in.args[0].value = inarg; |
b6aeaded MS |
632 | req->in.args[1].size = count; |
633 | req->out.numargs = 1; | |
634 | req->out.args[0].size = sizeof(struct fuse_write_out); | |
b25e82e5 MS |
635 | req->out.args[0].value = outarg; |
636 | } | |
637 | ||
638 | static size_t fuse_send_write(struct fuse_req *req, struct file *file, | |
f3332114 MS |
639 | struct inode *inode, loff_t pos, size_t count, |
640 | fl_owner_t owner) | |
b25e82e5 MS |
641 | { |
642 | struct fuse_conn *fc = get_fuse_conn(inode); | |
3be5a52b | 643 | fuse_write_fill(req, file, file->private_data, inode, pos, count, 0); |
f3332114 MS |
644 | if (owner != NULL) { |
645 | struct fuse_write_in *inarg = &req->misc.write.in; | |
646 | inarg->write_flags |= FUSE_WRITE_LOCKOWNER; | |
647 | inarg->lock_owner = fuse_lock_owner_id(fc, owner); | |
648 | } | |
b93f858a | 649 | fuse_request_send(fc, req); |
b25e82e5 | 650 | return req->misc.write.out.size; |
b6aeaded MS |
651 | } |
652 | ||
5e6f58a1 NP |
653 | static int fuse_write_begin(struct file *file, struct address_space *mapping, |
654 | loff_t pos, unsigned len, unsigned flags, | |
655 | struct page **pagep, void **fsdata) | |
b6aeaded | 656 | { |
5e6f58a1 NP |
657 | pgoff_t index = pos >> PAGE_CACHE_SHIFT; |
658 | ||
54566b2c | 659 | *pagep = grab_cache_page_write_begin(mapping, index, flags); |
5e6f58a1 NP |
660 | if (!*pagep) |
661 | return -ENOMEM; | |
b6aeaded MS |
662 | return 0; |
663 | } | |
664 | ||
854512ec MS |
665 | static void fuse_write_update_size(struct inode *inode, loff_t pos) |
666 | { | |
667 | struct fuse_conn *fc = get_fuse_conn(inode); | |
668 | struct fuse_inode *fi = get_fuse_inode(inode); | |
669 | ||
670 | spin_lock(&fc->lock); | |
671 | fi->attr_version = ++fc->attr_version; | |
672 | if (pos > inode->i_size) | |
673 | i_size_write(inode, pos); | |
674 | spin_unlock(&fc->lock); | |
675 | } | |
676 | ||
5e6f58a1 NP |
677 | static int fuse_buffered_write(struct file *file, struct inode *inode, |
678 | loff_t pos, unsigned count, struct page *page) | |
b6aeaded MS |
679 | { |
680 | int err; | |
04730fef | 681 | size_t nres; |
b6aeaded | 682 | struct fuse_conn *fc = get_fuse_conn(inode); |
5e6f58a1 | 683 | unsigned offset = pos & (PAGE_CACHE_SIZE - 1); |
248d86e8 MS |
684 | struct fuse_req *req; |
685 | ||
686 | if (is_bad_inode(inode)) | |
687 | return -EIO; | |
688 | ||
3be5a52b MS |
689 | /* |
690 | * Make sure writepages on the same page are not mixed up with | |
691 | * plain writes. | |
692 | */ | |
693 | fuse_wait_on_page_writeback(inode, page->index); | |
694 | ||
ce1d5a49 MS |
695 | req = fuse_get_req(fc); |
696 | if (IS_ERR(req)) | |
697 | return PTR_ERR(req); | |
b6aeaded | 698 | |
f4975c67 | 699 | req->in.argpages = 1; |
b6aeaded MS |
700 | req->num_pages = 1; |
701 | req->pages[0] = page; | |
702 | req->page_offset = offset; | |
f3332114 | 703 | nres = fuse_send_write(req, file, inode, pos, count, NULL); |
b6aeaded MS |
704 | err = req->out.h.error; |
705 | fuse_put_request(fc, req); | |
5e6f58a1 | 706 | if (!err && !nres) |
b6aeaded MS |
707 | err = -EIO; |
708 | if (!err) { | |
5e6f58a1 | 709 | pos += nres; |
854512ec | 710 | fuse_write_update_size(inode, pos); |
5e6f58a1 | 711 | if (count == PAGE_CACHE_SIZE) |
b6aeaded | 712 | SetPageUptodate(page); |
b36c31ba MS |
713 | } |
714 | fuse_invalidate_attr(inode); | |
5e6f58a1 NP |
715 | return err ? err : nres; |
716 | } | |
717 | ||
718 | static int fuse_write_end(struct file *file, struct address_space *mapping, | |
719 | loff_t pos, unsigned len, unsigned copied, | |
720 | struct page *page, void *fsdata) | |
721 | { | |
722 | struct inode *inode = mapping->host; | |
723 | int res = 0; | |
724 | ||
725 | if (copied) | |
726 | res = fuse_buffered_write(file, inode, pos, copied, page); | |
727 | ||
728 | unlock_page(page); | |
729 | page_cache_release(page); | |
730 | return res; | |
b6aeaded MS |
731 | } |
732 | ||
ea9b9907 NP |
733 | static size_t fuse_send_write_pages(struct fuse_req *req, struct file *file, |
734 | struct inode *inode, loff_t pos, | |
735 | size_t count) | |
736 | { | |
737 | size_t res; | |
738 | unsigned offset; | |
739 | unsigned i; | |
740 | ||
741 | for (i = 0; i < req->num_pages; i++) | |
742 | fuse_wait_on_page_writeback(inode, req->pages[i]->index); | |
743 | ||
744 | res = fuse_send_write(req, file, inode, pos, count, NULL); | |
745 | ||
746 | offset = req->page_offset; | |
747 | count = res; | |
748 | for (i = 0; i < req->num_pages; i++) { | |
749 | struct page *page = req->pages[i]; | |
750 | ||
751 | if (!req->out.h.error && !offset && count >= PAGE_CACHE_SIZE) | |
752 | SetPageUptodate(page); | |
753 | ||
754 | if (count > PAGE_CACHE_SIZE - offset) | |
755 | count -= PAGE_CACHE_SIZE - offset; | |
756 | else | |
757 | count = 0; | |
758 | offset = 0; | |
759 | ||
760 | unlock_page(page); | |
761 | page_cache_release(page); | |
762 | } | |
763 | ||
764 | return res; | |
765 | } | |
766 | ||
767 | static ssize_t fuse_fill_write_pages(struct fuse_req *req, | |
768 | struct address_space *mapping, | |
769 | struct iov_iter *ii, loff_t pos) | |
770 | { | |
771 | struct fuse_conn *fc = get_fuse_conn(mapping->host); | |
772 | unsigned offset = pos & (PAGE_CACHE_SIZE - 1); | |
773 | size_t count = 0; | |
774 | int err; | |
775 | ||
f4975c67 | 776 | req->in.argpages = 1; |
ea9b9907 NP |
777 | req->page_offset = offset; |
778 | ||
779 | do { | |
780 | size_t tmp; | |
781 | struct page *page; | |
782 | pgoff_t index = pos >> PAGE_CACHE_SHIFT; | |
783 | size_t bytes = min_t(size_t, PAGE_CACHE_SIZE - offset, | |
784 | iov_iter_count(ii)); | |
785 | ||
786 | bytes = min_t(size_t, bytes, fc->max_write - count); | |
787 | ||
788 | again: | |
789 | err = -EFAULT; | |
790 | if (iov_iter_fault_in_readable(ii, bytes)) | |
791 | break; | |
792 | ||
793 | err = -ENOMEM; | |
54566b2c | 794 | page = grab_cache_page_write_begin(mapping, index, 0); |
ea9b9907 NP |
795 | if (!page) |
796 | break; | |
797 | ||
798 | pagefault_disable(); | |
799 | tmp = iov_iter_copy_from_user_atomic(page, ii, offset, bytes); | |
800 | pagefault_enable(); | |
801 | flush_dcache_page(page); | |
802 | ||
803 | if (!tmp) { | |
804 | unlock_page(page); | |
805 | page_cache_release(page); | |
806 | bytes = min(bytes, iov_iter_single_seg_count(ii)); | |
807 | goto again; | |
808 | } | |
809 | ||
810 | err = 0; | |
811 | req->pages[req->num_pages] = page; | |
812 | req->num_pages++; | |
813 | ||
814 | iov_iter_advance(ii, tmp); | |
815 | count += tmp; | |
816 | pos += tmp; | |
817 | offset += tmp; | |
818 | if (offset == PAGE_CACHE_SIZE) | |
819 | offset = 0; | |
820 | ||
78bb6cb9 MS |
821 | if (!fc->big_writes) |
822 | break; | |
ea9b9907 NP |
823 | } while (iov_iter_count(ii) && count < fc->max_write && |
824 | req->num_pages < FUSE_MAX_PAGES_PER_REQ && offset == 0); | |
825 | ||
826 | return count > 0 ? count : err; | |
827 | } | |
828 | ||
829 | static ssize_t fuse_perform_write(struct file *file, | |
830 | struct address_space *mapping, | |
831 | struct iov_iter *ii, loff_t pos) | |
832 | { | |
833 | struct inode *inode = mapping->host; | |
834 | struct fuse_conn *fc = get_fuse_conn(inode); | |
835 | int err = 0; | |
836 | ssize_t res = 0; | |
837 | ||
838 | if (is_bad_inode(inode)) | |
839 | return -EIO; | |
840 | ||
841 | do { | |
842 | struct fuse_req *req; | |
843 | ssize_t count; | |
844 | ||
845 | req = fuse_get_req(fc); | |
846 | if (IS_ERR(req)) { | |
847 | err = PTR_ERR(req); | |
848 | break; | |
849 | } | |
850 | ||
851 | count = fuse_fill_write_pages(req, mapping, ii, pos); | |
852 | if (count <= 0) { | |
853 | err = count; | |
854 | } else { | |
855 | size_t num_written; | |
856 | ||
857 | num_written = fuse_send_write_pages(req, file, inode, | |
858 | pos, count); | |
859 | err = req->out.h.error; | |
860 | if (!err) { | |
861 | res += num_written; | |
862 | pos += num_written; | |
863 | ||
864 | /* break out of the loop on short write */ | |
865 | if (num_written != count) | |
866 | err = -EIO; | |
867 | } | |
868 | } | |
869 | fuse_put_request(fc, req); | |
870 | } while (!err && iov_iter_count(ii)); | |
871 | ||
872 | if (res > 0) | |
873 | fuse_write_update_size(inode, pos); | |
874 | ||
875 | fuse_invalidate_attr(inode); | |
876 | ||
877 | return res > 0 ? res : err; | |
878 | } | |
879 | ||
880 | static ssize_t fuse_file_aio_write(struct kiocb *iocb, const struct iovec *iov, | |
881 | unsigned long nr_segs, loff_t pos) | |
882 | { | |
883 | struct file *file = iocb->ki_filp; | |
884 | struct address_space *mapping = file->f_mapping; | |
885 | size_t count = 0; | |
886 | ssize_t written = 0; | |
887 | struct inode *inode = mapping->host; | |
888 | ssize_t err; | |
889 | struct iov_iter i; | |
890 | ||
891 | WARN_ON(iocb->ki_pos != pos); | |
892 | ||
893 | err = generic_segment_checks(iov, &nr_segs, &count, VERIFY_READ); | |
894 | if (err) | |
895 | return err; | |
896 | ||
897 | mutex_lock(&inode->i_mutex); | |
898 | vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE); | |
899 | ||
900 | /* We can write back this queue in page reclaim */ | |
901 | current->backing_dev_info = mapping->backing_dev_info; | |
902 | ||
903 | err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode)); | |
904 | if (err) | |
905 | goto out; | |
906 | ||
907 | if (count == 0) | |
908 | goto out; | |
909 | ||
2f1936b8 | 910 | err = file_remove_suid(file); |
ea9b9907 NP |
911 | if (err) |
912 | goto out; | |
913 | ||
914 | file_update_time(file); | |
915 | ||
916 | iov_iter_init(&i, iov, nr_segs, count, 0); | |
917 | written = fuse_perform_write(file, mapping, &i, pos); | |
918 | if (written >= 0) | |
919 | iocb->ki_pos = pos + written; | |
920 | ||
921 | out: | |
922 | current->backing_dev_info = NULL; | |
923 | mutex_unlock(&inode->i_mutex); | |
924 | ||
925 | return written ? written : err; | |
926 | } | |
927 | ||
413ef8cb MS |
928 | static void fuse_release_user_pages(struct fuse_req *req, int write) |
929 | { | |
930 | unsigned i; | |
931 | ||
932 | for (i = 0; i < req->num_pages; i++) { | |
933 | struct page *page = req->pages[i]; | |
934 | if (write) | |
935 | set_page_dirty_lock(page); | |
936 | put_page(page); | |
937 | } | |
938 | } | |
939 | ||
940 | static int fuse_get_user_pages(struct fuse_req *req, const char __user *buf, | |
f4975c67 | 941 | unsigned *nbytesp, int write) |
413ef8cb | 942 | { |
f4975c67 | 943 | unsigned nbytes = *nbytesp; |
413ef8cb MS |
944 | unsigned long user_addr = (unsigned long) buf; |
945 | unsigned offset = user_addr & ~PAGE_MASK; | |
946 | int npages; | |
947 | ||
f4975c67 MS |
948 | /* Special case for kernel I/O: can copy directly into the buffer */ |
949 | if (segment_eq(get_fs(), KERNEL_DS)) { | |
950 | if (write) | |
951 | req->in.args[1].value = (void *) user_addr; | |
952 | else | |
953 | req->out.args[0].value = (void *) user_addr; | |
954 | ||
955 | return 0; | |
956 | } | |
413ef8cb MS |
957 | |
958 | nbytes = min(nbytes, (unsigned) FUSE_MAX_PAGES_PER_REQ << PAGE_SHIFT); | |
959 | npages = (nbytes + offset + PAGE_SIZE - 1) >> PAGE_SHIFT; | |
bd730967 | 960 | npages = clamp(npages, 1, FUSE_MAX_PAGES_PER_REQ); |
413ef8cb | 961 | down_read(¤t->mm->mmap_sem); |
f4975c67 | 962 | npages = get_user_pages(current, current->mm, user_addr, npages, !write, |
413ef8cb MS |
963 | 0, req->pages, NULL); |
964 | up_read(¤t->mm->mmap_sem); | |
965 | if (npages < 0) | |
966 | return npages; | |
967 | ||
968 | req->num_pages = npages; | |
969 | req->page_offset = offset; | |
f4975c67 MS |
970 | |
971 | if (write) | |
972 | req->in.argpages = 1; | |
973 | else | |
974 | req->out.argpages = 1; | |
975 | ||
976 | nbytes = (req->num_pages << PAGE_SHIFT) - req->page_offset; | |
977 | *nbytesp = min(*nbytesp, nbytes); | |
978 | ||
413ef8cb MS |
979 | return 0; |
980 | } | |
981 | ||
982 | static ssize_t fuse_direct_io(struct file *file, const char __user *buf, | |
983 | size_t count, loff_t *ppos, int write) | |
984 | { | |
7706a9d6 | 985 | struct inode *inode = file->f_path.dentry->d_inode; |
413ef8cb MS |
986 | struct fuse_conn *fc = get_fuse_conn(inode); |
987 | size_t nmax = write ? fc->max_write : fc->max_read; | |
988 | loff_t pos = *ppos; | |
989 | ssize_t res = 0; | |
248d86e8 MS |
990 | struct fuse_req *req; |
991 | ||
992 | if (is_bad_inode(inode)) | |
993 | return -EIO; | |
994 | ||
ce1d5a49 MS |
995 | req = fuse_get_req(fc); |
996 | if (IS_ERR(req)) | |
997 | return PTR_ERR(req); | |
413ef8cb MS |
998 | |
999 | while (count) { | |
413ef8cb | 1000 | size_t nres; |
f4975c67 MS |
1001 | size_t nbytes = min(count, nmax); |
1002 | int err = fuse_get_user_pages(req, buf, &nbytes, write); | |
413ef8cb MS |
1003 | if (err) { |
1004 | res = err; | |
1005 | break; | |
1006 | } | |
f4975c67 | 1007 | |
413ef8cb | 1008 | if (write) |
f3332114 MS |
1009 | nres = fuse_send_write(req, file, inode, pos, nbytes, |
1010 | current->files); | |
413ef8cb | 1011 | else |
f3332114 MS |
1012 | nres = fuse_send_read(req, file, inode, pos, nbytes, |
1013 | current->files); | |
413ef8cb MS |
1014 | fuse_release_user_pages(req, !write); |
1015 | if (req->out.h.error) { | |
1016 | if (!res) | |
1017 | res = req->out.h.error; | |
1018 | break; | |
1019 | } else if (nres > nbytes) { | |
1020 | res = -EIO; | |
1021 | break; | |
1022 | } | |
1023 | count -= nres; | |
1024 | res += nres; | |
1025 | pos += nres; | |
1026 | buf += nres; | |
1027 | if (nres != nbytes) | |
1028 | break; | |
56cf34ff MS |
1029 | if (count) { |
1030 | fuse_put_request(fc, req); | |
1031 | req = fuse_get_req(fc); | |
1032 | if (IS_ERR(req)) | |
1033 | break; | |
1034 | } | |
413ef8cb MS |
1035 | } |
1036 | fuse_put_request(fc, req); | |
1037 | if (res > 0) { | |
854512ec MS |
1038 | if (write) |
1039 | fuse_write_update_size(inode, pos); | |
413ef8cb | 1040 | *ppos = pos; |
b36c31ba MS |
1041 | } |
1042 | fuse_invalidate_attr(inode); | |
413ef8cb MS |
1043 | |
1044 | return res; | |
1045 | } | |
1046 | ||
1047 | static ssize_t fuse_direct_read(struct file *file, char __user *buf, | |
1048 | size_t count, loff_t *ppos) | |
1049 | { | |
1050 | return fuse_direct_io(file, buf, count, ppos, 0); | |
1051 | } | |
1052 | ||
1053 | static ssize_t fuse_direct_write(struct file *file, const char __user *buf, | |
1054 | size_t count, loff_t *ppos) | |
1055 | { | |
7706a9d6 | 1056 | struct inode *inode = file->f_path.dentry->d_inode; |
413ef8cb MS |
1057 | ssize_t res; |
1058 | /* Don't allow parallel writes to the same file */ | |
1b1dcc1b | 1059 | mutex_lock(&inode->i_mutex); |
889f7848 MS |
1060 | res = generic_write_checks(file, ppos, &count, 0); |
1061 | if (!res) | |
1062 | res = fuse_direct_io(file, buf, count, ppos, 1); | |
1b1dcc1b | 1063 | mutex_unlock(&inode->i_mutex); |
413ef8cb MS |
1064 | return res; |
1065 | } | |
1066 | ||
3be5a52b | 1067 | static void fuse_writepage_free(struct fuse_conn *fc, struct fuse_req *req) |
b6aeaded | 1068 | { |
3be5a52b MS |
1069 | __free_page(req->pages[0]); |
1070 | fuse_file_put(req->ff); | |
3be5a52b MS |
1071 | } |
1072 | ||
1073 | static void fuse_writepage_finish(struct fuse_conn *fc, struct fuse_req *req) | |
1074 | { | |
1075 | struct inode *inode = req->inode; | |
1076 | struct fuse_inode *fi = get_fuse_inode(inode); | |
1077 | struct backing_dev_info *bdi = inode->i_mapping->backing_dev_info; | |
1078 | ||
1079 | list_del(&req->writepages_entry); | |
1080 | dec_bdi_stat(bdi, BDI_WRITEBACK); | |
1081 | dec_zone_page_state(req->pages[0], NR_WRITEBACK_TEMP); | |
1082 | bdi_writeout_inc(bdi); | |
1083 | wake_up(&fi->page_waitq); | |
1084 | } | |
1085 | ||
1086 | /* Called under fc->lock, may release and reacquire it */ | |
1087 | static void fuse_send_writepage(struct fuse_conn *fc, struct fuse_req *req) | |
5d9ec854 HH |
1088 | __releases(&fc->lock) |
1089 | __acquires(&fc->lock) | |
3be5a52b MS |
1090 | { |
1091 | struct fuse_inode *fi = get_fuse_inode(req->inode); | |
1092 | loff_t size = i_size_read(req->inode); | |
1093 | struct fuse_write_in *inarg = &req->misc.write.in; | |
1094 | ||
1095 | if (!fc->connected) | |
1096 | goto out_free; | |
1097 | ||
1098 | if (inarg->offset + PAGE_CACHE_SIZE <= size) { | |
1099 | inarg->size = PAGE_CACHE_SIZE; | |
1100 | } else if (inarg->offset < size) { | |
1101 | inarg->size = size & (PAGE_CACHE_SIZE - 1); | |
1102 | } else { | |
1103 | /* Got truncated off completely */ | |
1104 | goto out_free; | |
b6aeaded | 1105 | } |
3be5a52b MS |
1106 | |
1107 | req->in.args[1].size = inarg->size; | |
1108 | fi->writectr++; | |
b93f858a | 1109 | fuse_request_send_background_locked(fc, req); |
3be5a52b MS |
1110 | return; |
1111 | ||
1112 | out_free: | |
1113 | fuse_writepage_finish(fc, req); | |
1114 | spin_unlock(&fc->lock); | |
1115 | fuse_writepage_free(fc, req); | |
e9bb09dd | 1116 | fuse_put_request(fc, req); |
3be5a52b | 1117 | spin_lock(&fc->lock); |
b6aeaded MS |
1118 | } |
1119 | ||
3be5a52b MS |
1120 | /* |
1121 | * If fi->writectr is positive (no truncate or fsync going on) send | |
1122 | * all queued writepage requests. | |
1123 | * | |
1124 | * Called with fc->lock | |
1125 | */ | |
1126 | void fuse_flush_writepages(struct inode *inode) | |
5d9ec854 HH |
1127 | __releases(&fc->lock) |
1128 | __acquires(&fc->lock) | |
b6aeaded | 1129 | { |
3be5a52b MS |
1130 | struct fuse_conn *fc = get_fuse_conn(inode); |
1131 | struct fuse_inode *fi = get_fuse_inode(inode); | |
1132 | struct fuse_req *req; | |
1133 | ||
1134 | while (fi->writectr >= 0 && !list_empty(&fi->queued_writes)) { | |
1135 | req = list_entry(fi->queued_writes.next, struct fuse_req, list); | |
1136 | list_del_init(&req->list); | |
1137 | fuse_send_writepage(fc, req); | |
1138 | } | |
1139 | } | |
1140 | ||
1141 | static void fuse_writepage_end(struct fuse_conn *fc, struct fuse_req *req) | |
1142 | { | |
1143 | struct inode *inode = req->inode; | |
1144 | struct fuse_inode *fi = get_fuse_inode(inode); | |
1145 | ||
1146 | mapping_set_error(inode->i_mapping, req->out.h.error); | |
1147 | spin_lock(&fc->lock); | |
1148 | fi->writectr--; | |
1149 | fuse_writepage_finish(fc, req); | |
1150 | spin_unlock(&fc->lock); | |
1151 | fuse_writepage_free(fc, req); | |
1152 | } | |
1153 | ||
1154 | static int fuse_writepage_locked(struct page *page) | |
1155 | { | |
1156 | struct address_space *mapping = page->mapping; | |
1157 | struct inode *inode = mapping->host; | |
1158 | struct fuse_conn *fc = get_fuse_conn(inode); | |
1159 | struct fuse_inode *fi = get_fuse_inode(inode); | |
1160 | struct fuse_req *req; | |
1161 | struct fuse_file *ff; | |
1162 | struct page *tmp_page; | |
1163 | ||
1164 | set_page_writeback(page); | |
1165 | ||
1166 | req = fuse_request_alloc_nofs(); | |
1167 | if (!req) | |
1168 | goto err; | |
1169 | ||
1170 | tmp_page = alloc_page(GFP_NOFS | __GFP_HIGHMEM); | |
1171 | if (!tmp_page) | |
1172 | goto err_free; | |
1173 | ||
1174 | spin_lock(&fc->lock); | |
1175 | BUG_ON(list_empty(&fi->write_files)); | |
1176 | ff = list_entry(fi->write_files.next, struct fuse_file, write_entry); | |
1177 | req->ff = fuse_file_get(ff); | |
1178 | spin_unlock(&fc->lock); | |
1179 | ||
1180 | fuse_write_fill(req, NULL, ff, inode, page_offset(page), 0, 1); | |
1181 | ||
1182 | copy_highpage(tmp_page, page); | |
f4975c67 | 1183 | req->in.argpages = 1; |
3be5a52b MS |
1184 | req->num_pages = 1; |
1185 | req->pages[0] = tmp_page; | |
1186 | req->page_offset = 0; | |
1187 | req->end = fuse_writepage_end; | |
1188 | req->inode = inode; | |
1189 | ||
1190 | inc_bdi_stat(mapping->backing_dev_info, BDI_WRITEBACK); | |
1191 | inc_zone_page_state(tmp_page, NR_WRITEBACK_TEMP); | |
1192 | end_page_writeback(page); | |
1193 | ||
1194 | spin_lock(&fc->lock); | |
1195 | list_add(&req->writepages_entry, &fi->writepages); | |
1196 | list_add_tail(&req->list, &fi->queued_writes); | |
1197 | fuse_flush_writepages(inode); | |
1198 | spin_unlock(&fc->lock); | |
1199 | ||
1200 | return 0; | |
1201 | ||
1202 | err_free: | |
1203 | fuse_request_free(req); | |
1204 | err: | |
1205 | end_page_writeback(page); | |
1206 | return -ENOMEM; | |
1207 | } | |
1208 | ||
1209 | static int fuse_writepage(struct page *page, struct writeback_control *wbc) | |
1210 | { | |
1211 | int err; | |
1212 | ||
1213 | err = fuse_writepage_locked(page); | |
1214 | unlock_page(page); | |
1215 | ||
1216 | return err; | |
1217 | } | |
1218 | ||
1219 | static int fuse_launder_page(struct page *page) | |
1220 | { | |
1221 | int err = 0; | |
1222 | if (clear_page_dirty_for_io(page)) { | |
1223 | struct inode *inode = page->mapping->host; | |
1224 | err = fuse_writepage_locked(page); | |
1225 | if (!err) | |
1226 | fuse_wait_on_page_writeback(inode, page->index); | |
1227 | } | |
1228 | return err; | |
1229 | } | |
1230 | ||
1231 | /* | |
1232 | * Write back dirty pages now, because there may not be any suitable | |
1233 | * open files later | |
1234 | */ | |
1235 | static void fuse_vma_close(struct vm_area_struct *vma) | |
1236 | { | |
1237 | filemap_write_and_wait(vma->vm_file->f_mapping); | |
1238 | } | |
1239 | ||
1240 | /* | |
1241 | * Wait for writeback against this page to complete before allowing it | |
1242 | * to be marked dirty again, and hence written back again, possibly | |
1243 | * before the previous writepage completed. | |
1244 | * | |
1245 | * Block here, instead of in ->writepage(), so that the userspace fs | |
1246 | * can only block processes actually operating on the filesystem. | |
1247 | * | |
1248 | * Otherwise unprivileged userspace fs would be able to block | |
1249 | * unrelated: | |
1250 | * | |
1251 | * - page migration | |
1252 | * - sync(2) | |
1253 | * - try_to_free_pages() with order > PAGE_ALLOC_COSTLY_ORDER | |
1254 | */ | |
c2ec175c | 1255 | static int fuse_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) |
3be5a52b | 1256 | { |
c2ec175c | 1257 | struct page *page = vmf->page; |
3be5a52b MS |
1258 | /* |
1259 | * Don't use page->mapping as it may become NULL from a | |
1260 | * concurrent truncate. | |
1261 | */ | |
1262 | struct inode *inode = vma->vm_file->f_mapping->host; | |
1263 | ||
1264 | fuse_wait_on_page_writeback(inode, page->index); | |
1265 | return 0; | |
1266 | } | |
1267 | ||
1268 | static struct vm_operations_struct fuse_file_vm_ops = { | |
1269 | .close = fuse_vma_close, | |
1270 | .fault = filemap_fault, | |
1271 | .page_mkwrite = fuse_page_mkwrite, | |
1272 | }; | |
1273 | ||
1274 | static int fuse_file_mmap(struct file *file, struct vm_area_struct *vma) | |
1275 | { | |
1276 | if ((vma->vm_flags & VM_SHARED) && (vma->vm_flags & VM_MAYWRITE)) { | |
1277 | struct inode *inode = file->f_dentry->d_inode; | |
1278 | struct fuse_conn *fc = get_fuse_conn(inode); | |
1279 | struct fuse_inode *fi = get_fuse_inode(inode); | |
1280 | struct fuse_file *ff = file->private_data; | |
1281 | /* | |
1282 | * file may be written through mmap, so chain it onto the | |
1283 | * inodes's write_file list | |
1284 | */ | |
1285 | spin_lock(&fc->lock); | |
1286 | if (list_empty(&ff->write_entry)) | |
1287 | list_add(&ff->write_entry, &fi->write_files); | |
1288 | spin_unlock(&fc->lock); | |
1289 | } | |
1290 | file_accessed(file); | |
1291 | vma->vm_ops = &fuse_file_vm_ops; | |
b6aeaded MS |
1292 | return 0; |
1293 | } | |
1294 | ||
fc280c96 MS |
1295 | static int fuse_direct_mmap(struct file *file, struct vm_area_struct *vma) |
1296 | { | |
1297 | /* Can't provide the coherency needed for MAP_SHARED */ | |
1298 | if (vma->vm_flags & VM_MAYSHARE) | |
1299 | return -ENODEV; | |
1300 | ||
1301 | return generic_file_mmap(file, vma); | |
1302 | } | |
1303 | ||
71421259 MS |
1304 | static int convert_fuse_file_lock(const struct fuse_file_lock *ffl, |
1305 | struct file_lock *fl) | |
1306 | { | |
1307 | switch (ffl->type) { | |
1308 | case F_UNLCK: | |
1309 | break; | |
1310 | ||
1311 | case F_RDLCK: | |
1312 | case F_WRLCK: | |
1313 | if (ffl->start > OFFSET_MAX || ffl->end > OFFSET_MAX || | |
1314 | ffl->end < ffl->start) | |
1315 | return -EIO; | |
1316 | ||
1317 | fl->fl_start = ffl->start; | |
1318 | fl->fl_end = ffl->end; | |
1319 | fl->fl_pid = ffl->pid; | |
1320 | break; | |
1321 | ||
1322 | default: | |
1323 | return -EIO; | |
1324 | } | |
1325 | fl->fl_type = ffl->type; | |
1326 | return 0; | |
1327 | } | |
1328 | ||
1329 | static void fuse_lk_fill(struct fuse_req *req, struct file *file, | |
a9ff4f87 MS |
1330 | const struct file_lock *fl, int opcode, pid_t pid, |
1331 | int flock) | |
71421259 | 1332 | { |
7706a9d6 | 1333 | struct inode *inode = file->f_path.dentry->d_inode; |
9c8ef561 | 1334 | struct fuse_conn *fc = get_fuse_conn(inode); |
71421259 MS |
1335 | struct fuse_file *ff = file->private_data; |
1336 | struct fuse_lk_in *arg = &req->misc.lk_in; | |
1337 | ||
1338 | arg->fh = ff->fh; | |
9c8ef561 | 1339 | arg->owner = fuse_lock_owner_id(fc, fl->fl_owner); |
71421259 MS |
1340 | arg->lk.start = fl->fl_start; |
1341 | arg->lk.end = fl->fl_end; | |
1342 | arg->lk.type = fl->fl_type; | |
1343 | arg->lk.pid = pid; | |
a9ff4f87 MS |
1344 | if (flock) |
1345 | arg->lk_flags |= FUSE_LK_FLOCK; | |
71421259 MS |
1346 | req->in.h.opcode = opcode; |
1347 | req->in.h.nodeid = get_node_id(inode); | |
1348 | req->in.numargs = 1; | |
1349 | req->in.args[0].size = sizeof(*arg); | |
1350 | req->in.args[0].value = arg; | |
1351 | } | |
1352 | ||
1353 | static int fuse_getlk(struct file *file, struct file_lock *fl) | |
1354 | { | |
7706a9d6 | 1355 | struct inode *inode = file->f_path.dentry->d_inode; |
71421259 MS |
1356 | struct fuse_conn *fc = get_fuse_conn(inode); |
1357 | struct fuse_req *req; | |
1358 | struct fuse_lk_out outarg; | |
1359 | int err; | |
1360 | ||
1361 | req = fuse_get_req(fc); | |
1362 | if (IS_ERR(req)) | |
1363 | return PTR_ERR(req); | |
1364 | ||
a9ff4f87 | 1365 | fuse_lk_fill(req, file, fl, FUSE_GETLK, 0, 0); |
71421259 MS |
1366 | req->out.numargs = 1; |
1367 | req->out.args[0].size = sizeof(outarg); | |
1368 | req->out.args[0].value = &outarg; | |
b93f858a | 1369 | fuse_request_send(fc, req); |
71421259 MS |
1370 | err = req->out.h.error; |
1371 | fuse_put_request(fc, req); | |
1372 | if (!err) | |
1373 | err = convert_fuse_file_lock(&outarg.lk, fl); | |
1374 | ||
1375 | return err; | |
1376 | } | |
1377 | ||
a9ff4f87 | 1378 | static int fuse_setlk(struct file *file, struct file_lock *fl, int flock) |
71421259 | 1379 | { |
7706a9d6 | 1380 | struct inode *inode = file->f_path.dentry->d_inode; |
71421259 MS |
1381 | struct fuse_conn *fc = get_fuse_conn(inode); |
1382 | struct fuse_req *req; | |
1383 | int opcode = (fl->fl_flags & FL_SLEEP) ? FUSE_SETLKW : FUSE_SETLK; | |
1384 | pid_t pid = fl->fl_type != F_UNLCK ? current->tgid : 0; | |
1385 | int err; | |
1386 | ||
48e90761 MS |
1387 | if (fl->fl_lmops && fl->fl_lmops->fl_grant) { |
1388 | /* NLM needs asynchronous locks, which we don't support yet */ | |
1389 | return -ENOLCK; | |
1390 | } | |
1391 | ||
71421259 MS |
1392 | /* Unlock on close is handled by the flush method */ |
1393 | if (fl->fl_flags & FL_CLOSE) | |
1394 | return 0; | |
1395 | ||
1396 | req = fuse_get_req(fc); | |
1397 | if (IS_ERR(req)) | |
1398 | return PTR_ERR(req); | |
1399 | ||
a9ff4f87 | 1400 | fuse_lk_fill(req, file, fl, opcode, pid, flock); |
b93f858a | 1401 | fuse_request_send(fc, req); |
71421259 | 1402 | err = req->out.h.error; |
a4d27e75 MS |
1403 | /* locking is restartable */ |
1404 | if (err == -EINTR) | |
1405 | err = -ERESTARTSYS; | |
71421259 MS |
1406 | fuse_put_request(fc, req); |
1407 | return err; | |
1408 | } | |
1409 | ||
1410 | static int fuse_file_lock(struct file *file, int cmd, struct file_lock *fl) | |
1411 | { | |
7706a9d6 | 1412 | struct inode *inode = file->f_path.dentry->d_inode; |
71421259 MS |
1413 | struct fuse_conn *fc = get_fuse_conn(inode); |
1414 | int err; | |
1415 | ||
48e90761 MS |
1416 | if (cmd == F_CANCELLK) { |
1417 | err = 0; | |
1418 | } else if (cmd == F_GETLK) { | |
71421259 | 1419 | if (fc->no_lock) { |
9d6a8c5c | 1420 | posix_test_lock(file, fl); |
71421259 MS |
1421 | err = 0; |
1422 | } else | |
1423 | err = fuse_getlk(file, fl); | |
1424 | } else { | |
1425 | if (fc->no_lock) | |
48e90761 | 1426 | err = posix_lock_file(file, fl, NULL); |
71421259 | 1427 | else |
a9ff4f87 | 1428 | err = fuse_setlk(file, fl, 0); |
71421259 MS |
1429 | } |
1430 | return err; | |
1431 | } | |
1432 | ||
a9ff4f87 MS |
1433 | static int fuse_file_flock(struct file *file, int cmd, struct file_lock *fl) |
1434 | { | |
1435 | struct inode *inode = file->f_path.dentry->d_inode; | |
1436 | struct fuse_conn *fc = get_fuse_conn(inode); | |
1437 | int err; | |
1438 | ||
1439 | if (fc->no_lock) { | |
1440 | err = flock_lock_file_wait(file, fl); | |
1441 | } else { | |
1442 | /* emulate flock with POSIX locks */ | |
1443 | fl->fl_owner = (fl_owner_t) file; | |
1444 | err = fuse_setlk(file, fl, 1); | |
1445 | } | |
1446 | ||
1447 | return err; | |
1448 | } | |
1449 | ||
b2d2272f MS |
1450 | static sector_t fuse_bmap(struct address_space *mapping, sector_t block) |
1451 | { | |
1452 | struct inode *inode = mapping->host; | |
1453 | struct fuse_conn *fc = get_fuse_conn(inode); | |
1454 | struct fuse_req *req; | |
1455 | struct fuse_bmap_in inarg; | |
1456 | struct fuse_bmap_out outarg; | |
1457 | int err; | |
1458 | ||
1459 | if (!inode->i_sb->s_bdev || fc->no_bmap) | |
1460 | return 0; | |
1461 | ||
1462 | req = fuse_get_req(fc); | |
1463 | if (IS_ERR(req)) | |
1464 | return 0; | |
1465 | ||
1466 | memset(&inarg, 0, sizeof(inarg)); | |
1467 | inarg.block = block; | |
1468 | inarg.blocksize = inode->i_sb->s_blocksize; | |
1469 | req->in.h.opcode = FUSE_BMAP; | |
1470 | req->in.h.nodeid = get_node_id(inode); | |
1471 | req->in.numargs = 1; | |
1472 | req->in.args[0].size = sizeof(inarg); | |
1473 | req->in.args[0].value = &inarg; | |
1474 | req->out.numargs = 1; | |
1475 | req->out.args[0].size = sizeof(outarg); | |
1476 | req->out.args[0].value = &outarg; | |
b93f858a | 1477 | fuse_request_send(fc, req); |
b2d2272f MS |
1478 | err = req->out.h.error; |
1479 | fuse_put_request(fc, req); | |
1480 | if (err == -ENOSYS) | |
1481 | fc->no_bmap = 1; | |
1482 | ||
1483 | return err ? 0 : outarg.block; | |
1484 | } | |
1485 | ||
5559b8f4 MS |
1486 | static loff_t fuse_file_llseek(struct file *file, loff_t offset, int origin) |
1487 | { | |
1488 | loff_t retval; | |
1489 | struct inode *inode = file->f_path.dentry->d_inode; | |
1490 | ||
1491 | mutex_lock(&inode->i_mutex); | |
1492 | switch (origin) { | |
1493 | case SEEK_END: | |
769415c6 MS |
1494 | retval = fuse_update_attributes(inode, NULL, file, NULL); |
1495 | if (retval) | |
5291658d | 1496 | goto exit; |
5559b8f4 MS |
1497 | offset += i_size_read(inode); |
1498 | break; | |
1499 | case SEEK_CUR: | |
1500 | offset += file->f_pos; | |
1501 | } | |
1502 | retval = -EINVAL; | |
1503 | if (offset >= 0 && offset <= inode->i_sb->s_maxbytes) { | |
1504 | if (offset != file->f_pos) { | |
1505 | file->f_pos = offset; | |
1506 | file->f_version = 0; | |
1507 | } | |
1508 | retval = offset; | |
1509 | } | |
5291658d | 1510 | exit: |
5559b8f4 MS |
1511 | mutex_unlock(&inode->i_mutex); |
1512 | return retval; | |
1513 | } | |
1514 | ||
59efec7b TH |
1515 | static int fuse_ioctl_copy_user(struct page **pages, struct iovec *iov, |
1516 | unsigned int nr_segs, size_t bytes, bool to_user) | |
1517 | { | |
1518 | struct iov_iter ii; | |
1519 | int page_idx = 0; | |
1520 | ||
1521 | if (!bytes) | |
1522 | return 0; | |
1523 | ||
1524 | iov_iter_init(&ii, iov, nr_segs, bytes, 0); | |
1525 | ||
1526 | while (iov_iter_count(&ii)) { | |
1527 | struct page *page = pages[page_idx++]; | |
1528 | size_t todo = min_t(size_t, PAGE_SIZE, iov_iter_count(&ii)); | |
1529 | void *kaddr, *map; | |
1530 | ||
1531 | kaddr = map = kmap(page); | |
1532 | ||
1533 | while (todo) { | |
1534 | char __user *uaddr = ii.iov->iov_base + ii.iov_offset; | |
1535 | size_t iov_len = ii.iov->iov_len - ii.iov_offset; | |
1536 | size_t copy = min(todo, iov_len); | |
1537 | size_t left; | |
1538 | ||
1539 | if (!to_user) | |
1540 | left = copy_from_user(kaddr, uaddr, copy); | |
1541 | else | |
1542 | left = copy_to_user(uaddr, kaddr, copy); | |
1543 | ||
1544 | if (unlikely(left)) | |
1545 | return -EFAULT; | |
1546 | ||
1547 | iov_iter_advance(&ii, copy); | |
1548 | todo -= copy; | |
1549 | kaddr += copy; | |
1550 | } | |
1551 | ||
1552 | kunmap(map); | |
1553 | } | |
1554 | ||
1555 | return 0; | |
1556 | } | |
1557 | ||
1558 | /* | |
1559 | * For ioctls, there is no generic way to determine how much memory | |
1560 | * needs to be read and/or written. Furthermore, ioctls are allowed | |
1561 | * to dereference the passed pointer, so the parameter requires deep | |
1562 | * copying but FUSE has no idea whatsoever about what to copy in or | |
1563 | * out. | |
1564 | * | |
1565 | * This is solved by allowing FUSE server to retry ioctl with | |
1566 | * necessary in/out iovecs. Let's assume the ioctl implementation | |
1567 | * needs to read in the following structure. | |
1568 | * | |
1569 | * struct a { | |
1570 | * char *buf; | |
1571 | * size_t buflen; | |
1572 | * } | |
1573 | * | |
1574 | * On the first callout to FUSE server, inarg->in_size and | |
1575 | * inarg->out_size will be NULL; then, the server completes the ioctl | |
1576 | * with FUSE_IOCTL_RETRY set in out->flags, out->in_iovs set to 1 and | |
1577 | * the actual iov array to | |
1578 | * | |
1579 | * { { .iov_base = inarg.arg, .iov_len = sizeof(struct a) } } | |
1580 | * | |
1581 | * which tells FUSE to copy in the requested area and retry the ioctl. | |
1582 | * On the second round, the server has access to the structure and | |
1583 | * from that it can tell what to look for next, so on the invocation, | |
1584 | * it sets FUSE_IOCTL_RETRY, out->in_iovs to 2 and iov array to | |
1585 | * | |
1586 | * { { .iov_base = inarg.arg, .iov_len = sizeof(struct a) }, | |
1587 | * { .iov_base = a.buf, .iov_len = a.buflen } } | |
1588 | * | |
1589 | * FUSE will copy both struct a and the pointed buffer from the | |
1590 | * process doing the ioctl and retry ioctl with both struct a and the | |
1591 | * buffer. | |
1592 | * | |
1593 | * This time, FUSE server has everything it needs and completes ioctl | |
1594 | * without FUSE_IOCTL_RETRY which finishes the ioctl call. | |
1595 | * | |
1596 | * Copying data out works the same way. | |
1597 | * | |
1598 | * Note that if FUSE_IOCTL_UNRESTRICTED is clear, the kernel | |
1599 | * automatically initializes in and out iovs by decoding @cmd with | |
1600 | * _IOC_* macros and the server is not allowed to request RETRY. This | |
1601 | * limits ioctl data transfers to well-formed ioctls and is the forced | |
1602 | * behavior for all FUSE servers. | |
1603 | */ | |
1604 | static long fuse_file_do_ioctl(struct file *file, unsigned int cmd, | |
1605 | unsigned long arg, unsigned int flags) | |
1606 | { | |
1607 | struct inode *inode = file->f_dentry->d_inode; | |
1608 | struct fuse_file *ff = file->private_data; | |
1609 | struct fuse_conn *fc = get_fuse_conn(inode); | |
1610 | struct fuse_ioctl_in inarg = { | |
1611 | .fh = ff->fh, | |
1612 | .cmd = cmd, | |
1613 | .arg = arg, | |
1614 | .flags = flags | |
1615 | }; | |
1616 | struct fuse_ioctl_out outarg; | |
1617 | struct fuse_req *req = NULL; | |
1618 | struct page **pages = NULL; | |
1619 | struct page *iov_page = NULL; | |
1620 | struct iovec *in_iov = NULL, *out_iov = NULL; | |
1621 | unsigned int in_iovs = 0, out_iovs = 0, num_pages = 0, max_pages; | |
1622 | size_t in_size, out_size, transferred; | |
1623 | int err; | |
1624 | ||
1625 | /* assume all the iovs returned by client always fits in a page */ | |
1626 | BUILD_BUG_ON(sizeof(struct iovec) * FUSE_IOCTL_MAX_IOV > PAGE_SIZE); | |
1627 | ||
1628 | if (!fuse_allow_task(fc, current)) | |
1629 | return -EACCES; | |
1630 | ||
1631 | err = -EIO; | |
1632 | if (is_bad_inode(inode)) | |
1633 | goto out; | |
1634 | ||
1635 | err = -ENOMEM; | |
1636 | pages = kzalloc(sizeof(pages[0]) * FUSE_MAX_PAGES_PER_REQ, GFP_KERNEL); | |
1637 | iov_page = alloc_page(GFP_KERNEL); | |
1638 | if (!pages || !iov_page) | |
1639 | goto out; | |
1640 | ||
1641 | /* | |
1642 | * If restricted, initialize IO parameters as encoded in @cmd. | |
1643 | * RETRY from server is not allowed. | |
1644 | */ | |
1645 | if (!(flags & FUSE_IOCTL_UNRESTRICTED)) { | |
1646 | struct iovec *iov = page_address(iov_page); | |
1647 | ||
c9f0523d | 1648 | iov->iov_base = (void __user *)arg; |
59efec7b TH |
1649 | iov->iov_len = _IOC_SIZE(cmd); |
1650 | ||
1651 | if (_IOC_DIR(cmd) & _IOC_WRITE) { | |
1652 | in_iov = iov; | |
1653 | in_iovs = 1; | |
1654 | } | |
1655 | ||
1656 | if (_IOC_DIR(cmd) & _IOC_READ) { | |
1657 | out_iov = iov; | |
1658 | out_iovs = 1; | |
1659 | } | |
1660 | } | |
1661 | ||
1662 | retry: | |
1663 | inarg.in_size = in_size = iov_length(in_iov, in_iovs); | |
1664 | inarg.out_size = out_size = iov_length(out_iov, out_iovs); | |
1665 | ||
1666 | /* | |
1667 | * Out data can be used either for actual out data or iovs, | |
1668 | * make sure there always is at least one page. | |
1669 | */ | |
1670 | out_size = max_t(size_t, out_size, PAGE_SIZE); | |
1671 | max_pages = DIV_ROUND_UP(max(in_size, out_size), PAGE_SIZE); | |
1672 | ||
1673 | /* make sure there are enough buffer pages and init request with them */ | |
1674 | err = -ENOMEM; | |
1675 | if (max_pages > FUSE_MAX_PAGES_PER_REQ) | |
1676 | goto out; | |
1677 | while (num_pages < max_pages) { | |
1678 | pages[num_pages] = alloc_page(GFP_KERNEL | __GFP_HIGHMEM); | |
1679 | if (!pages[num_pages]) | |
1680 | goto out; | |
1681 | num_pages++; | |
1682 | } | |
1683 | ||
1684 | req = fuse_get_req(fc); | |
1685 | if (IS_ERR(req)) { | |
1686 | err = PTR_ERR(req); | |
1687 | req = NULL; | |
1688 | goto out; | |
1689 | } | |
1690 | memcpy(req->pages, pages, sizeof(req->pages[0]) * num_pages); | |
1691 | req->num_pages = num_pages; | |
1692 | ||
1693 | /* okay, let's send it to the client */ | |
1694 | req->in.h.opcode = FUSE_IOCTL; | |
1695 | req->in.h.nodeid = get_node_id(inode); | |
1696 | req->in.numargs = 1; | |
1697 | req->in.args[0].size = sizeof(inarg); | |
1698 | req->in.args[0].value = &inarg; | |
1699 | if (in_size) { | |
1700 | req->in.numargs++; | |
1701 | req->in.args[1].size = in_size; | |
1702 | req->in.argpages = 1; | |
1703 | ||
1704 | err = fuse_ioctl_copy_user(pages, in_iov, in_iovs, in_size, | |
1705 | false); | |
1706 | if (err) | |
1707 | goto out; | |
1708 | } | |
1709 | ||
1710 | req->out.numargs = 2; | |
1711 | req->out.args[0].size = sizeof(outarg); | |
1712 | req->out.args[0].value = &outarg; | |
1713 | req->out.args[1].size = out_size; | |
1714 | req->out.argpages = 1; | |
1715 | req->out.argvar = 1; | |
1716 | ||
b93f858a | 1717 | fuse_request_send(fc, req); |
59efec7b TH |
1718 | err = req->out.h.error; |
1719 | transferred = req->out.args[1].size; | |
1720 | fuse_put_request(fc, req); | |
1721 | req = NULL; | |
1722 | if (err) | |
1723 | goto out; | |
1724 | ||
1725 | /* did it ask for retry? */ | |
1726 | if (outarg.flags & FUSE_IOCTL_RETRY) { | |
1727 | char *vaddr; | |
1728 | ||
1729 | /* no retry if in restricted mode */ | |
1730 | err = -EIO; | |
1731 | if (!(flags & FUSE_IOCTL_UNRESTRICTED)) | |
1732 | goto out; | |
1733 | ||
1734 | in_iovs = outarg.in_iovs; | |
1735 | out_iovs = outarg.out_iovs; | |
1736 | ||
1737 | /* | |
1738 | * Make sure things are in boundary, separate checks | |
1739 | * are to protect against overflow. | |
1740 | */ | |
1741 | err = -ENOMEM; | |
1742 | if (in_iovs > FUSE_IOCTL_MAX_IOV || | |
1743 | out_iovs > FUSE_IOCTL_MAX_IOV || | |
1744 | in_iovs + out_iovs > FUSE_IOCTL_MAX_IOV) | |
1745 | goto out; | |
1746 | ||
1747 | err = -EIO; | |
1748 | if ((in_iovs + out_iovs) * sizeof(struct iovec) != transferred) | |
1749 | goto out; | |
1750 | ||
1751 | /* okay, copy in iovs and retry */ | |
1752 | vaddr = kmap_atomic(pages[0], KM_USER0); | |
1753 | memcpy(page_address(iov_page), vaddr, transferred); | |
1754 | kunmap_atomic(vaddr, KM_USER0); | |
1755 | ||
1756 | in_iov = page_address(iov_page); | |
1757 | out_iov = in_iov + in_iovs; | |
1758 | ||
1759 | goto retry; | |
1760 | } | |
1761 | ||
1762 | err = -EIO; | |
1763 | if (transferred > inarg.out_size) | |
1764 | goto out; | |
1765 | ||
1766 | err = fuse_ioctl_copy_user(pages, out_iov, out_iovs, transferred, true); | |
1767 | out: | |
1768 | if (req) | |
1769 | fuse_put_request(fc, req); | |
1770 | if (iov_page) | |
1771 | __free_page(iov_page); | |
1772 | while (num_pages) | |
1773 | __free_page(pages[--num_pages]); | |
1774 | kfree(pages); | |
1775 | ||
1776 | return err ? err : outarg.result; | |
1777 | } | |
1778 | ||
1779 | static long fuse_file_ioctl(struct file *file, unsigned int cmd, | |
1780 | unsigned long arg) | |
1781 | { | |
1782 | return fuse_file_do_ioctl(file, cmd, arg, 0); | |
1783 | } | |
1784 | ||
1785 | static long fuse_file_compat_ioctl(struct file *file, unsigned int cmd, | |
1786 | unsigned long arg) | |
1787 | { | |
1788 | return fuse_file_do_ioctl(file, cmd, arg, FUSE_IOCTL_COMPAT); | |
1789 | } | |
1790 | ||
95668a69 TH |
1791 | /* |
1792 | * All files which have been polled are linked to RB tree | |
1793 | * fuse_conn->polled_files which is indexed by kh. Walk the tree and | |
1794 | * find the matching one. | |
1795 | */ | |
1796 | static struct rb_node **fuse_find_polled_node(struct fuse_conn *fc, u64 kh, | |
1797 | struct rb_node **parent_out) | |
1798 | { | |
1799 | struct rb_node **link = &fc->polled_files.rb_node; | |
1800 | struct rb_node *last = NULL; | |
1801 | ||
1802 | while (*link) { | |
1803 | struct fuse_file *ff; | |
1804 | ||
1805 | last = *link; | |
1806 | ff = rb_entry(last, struct fuse_file, polled_node); | |
1807 | ||
1808 | if (kh < ff->kh) | |
1809 | link = &last->rb_left; | |
1810 | else if (kh > ff->kh) | |
1811 | link = &last->rb_right; | |
1812 | else | |
1813 | return link; | |
1814 | } | |
1815 | ||
1816 | if (parent_out) | |
1817 | *parent_out = last; | |
1818 | return link; | |
1819 | } | |
1820 | ||
1821 | /* | |
1822 | * The file is about to be polled. Make sure it's on the polled_files | |
1823 | * RB tree. Note that files once added to the polled_files tree are | |
1824 | * not removed before the file is released. This is because a file | |
1825 | * polled once is likely to be polled again. | |
1826 | */ | |
1827 | static void fuse_register_polled_file(struct fuse_conn *fc, | |
1828 | struct fuse_file *ff) | |
1829 | { | |
1830 | spin_lock(&fc->lock); | |
1831 | if (RB_EMPTY_NODE(&ff->polled_node)) { | |
1832 | struct rb_node **link, *parent; | |
1833 | ||
1834 | link = fuse_find_polled_node(fc, ff->kh, &parent); | |
1835 | BUG_ON(*link); | |
1836 | rb_link_node(&ff->polled_node, parent, link); | |
1837 | rb_insert_color(&ff->polled_node, &fc->polled_files); | |
1838 | } | |
1839 | spin_unlock(&fc->lock); | |
1840 | } | |
1841 | ||
1842 | static unsigned fuse_file_poll(struct file *file, poll_table *wait) | |
1843 | { | |
1844 | struct inode *inode = file->f_dentry->d_inode; | |
1845 | struct fuse_file *ff = file->private_data; | |
1846 | struct fuse_conn *fc = get_fuse_conn(inode); | |
1847 | struct fuse_poll_in inarg = { .fh = ff->fh, .kh = ff->kh }; | |
1848 | struct fuse_poll_out outarg; | |
1849 | struct fuse_req *req; | |
1850 | int err; | |
1851 | ||
1852 | if (fc->no_poll) | |
1853 | return DEFAULT_POLLMASK; | |
1854 | ||
1855 | poll_wait(file, &ff->poll_wait, wait); | |
1856 | ||
1857 | /* | |
1858 | * Ask for notification iff there's someone waiting for it. | |
1859 | * The client may ignore the flag and always notify. | |
1860 | */ | |
1861 | if (waitqueue_active(&ff->poll_wait)) { | |
1862 | inarg.flags |= FUSE_POLL_SCHEDULE_NOTIFY; | |
1863 | fuse_register_polled_file(fc, ff); | |
1864 | } | |
1865 | ||
1866 | req = fuse_get_req(fc); | |
1867 | if (IS_ERR(req)) | |
1868 | return PTR_ERR(req); | |
1869 | ||
1870 | req->in.h.opcode = FUSE_POLL; | |
1871 | req->in.h.nodeid = get_node_id(inode); | |
1872 | req->in.numargs = 1; | |
1873 | req->in.args[0].size = sizeof(inarg); | |
1874 | req->in.args[0].value = &inarg; | |
1875 | req->out.numargs = 1; | |
1876 | req->out.args[0].size = sizeof(outarg); | |
1877 | req->out.args[0].value = &outarg; | |
b93f858a | 1878 | fuse_request_send(fc, req); |
95668a69 TH |
1879 | err = req->out.h.error; |
1880 | fuse_put_request(fc, req); | |
1881 | ||
1882 | if (!err) | |
1883 | return outarg.revents; | |
1884 | if (err == -ENOSYS) { | |
1885 | fc->no_poll = 1; | |
1886 | return DEFAULT_POLLMASK; | |
1887 | } | |
1888 | return POLLERR; | |
1889 | } | |
1890 | ||
1891 | /* | |
1892 | * This is called from fuse_handle_notify() on FUSE_NOTIFY_POLL and | |
1893 | * wakes up the poll waiters. | |
1894 | */ | |
1895 | int fuse_notify_poll_wakeup(struct fuse_conn *fc, | |
1896 | struct fuse_notify_poll_wakeup_out *outarg) | |
1897 | { | |
1898 | u64 kh = outarg->kh; | |
1899 | struct rb_node **link; | |
1900 | ||
1901 | spin_lock(&fc->lock); | |
1902 | ||
1903 | link = fuse_find_polled_node(fc, kh, NULL); | |
1904 | if (*link) { | |
1905 | struct fuse_file *ff; | |
1906 | ||
1907 | ff = rb_entry(*link, struct fuse_file, polled_node); | |
1908 | wake_up_interruptible_sync(&ff->poll_wait); | |
1909 | } | |
1910 | ||
1911 | spin_unlock(&fc->lock); | |
1912 | return 0; | |
1913 | } | |
1914 | ||
4b6f5d20 | 1915 | static const struct file_operations fuse_file_operations = { |
5559b8f4 | 1916 | .llseek = fuse_file_llseek, |
543ade1f | 1917 | .read = do_sync_read, |
bcb4be80 | 1918 | .aio_read = fuse_file_aio_read, |
543ade1f | 1919 | .write = do_sync_write, |
ea9b9907 | 1920 | .aio_write = fuse_file_aio_write, |
b6aeaded MS |
1921 | .mmap = fuse_file_mmap, |
1922 | .open = fuse_open, | |
1923 | .flush = fuse_flush, | |
1924 | .release = fuse_release, | |
1925 | .fsync = fuse_fsync, | |
71421259 | 1926 | .lock = fuse_file_lock, |
a9ff4f87 | 1927 | .flock = fuse_file_flock, |
5ffc4ef4 | 1928 | .splice_read = generic_file_splice_read, |
59efec7b TH |
1929 | .unlocked_ioctl = fuse_file_ioctl, |
1930 | .compat_ioctl = fuse_file_compat_ioctl, | |
95668a69 | 1931 | .poll = fuse_file_poll, |
b6aeaded MS |
1932 | }; |
1933 | ||
4b6f5d20 | 1934 | static const struct file_operations fuse_direct_io_file_operations = { |
5559b8f4 | 1935 | .llseek = fuse_file_llseek, |
413ef8cb MS |
1936 | .read = fuse_direct_read, |
1937 | .write = fuse_direct_write, | |
fc280c96 | 1938 | .mmap = fuse_direct_mmap, |
413ef8cb MS |
1939 | .open = fuse_open, |
1940 | .flush = fuse_flush, | |
1941 | .release = fuse_release, | |
1942 | .fsync = fuse_fsync, | |
71421259 | 1943 | .lock = fuse_file_lock, |
a9ff4f87 | 1944 | .flock = fuse_file_flock, |
59efec7b TH |
1945 | .unlocked_ioctl = fuse_file_ioctl, |
1946 | .compat_ioctl = fuse_file_compat_ioctl, | |
95668a69 | 1947 | .poll = fuse_file_poll, |
fc280c96 | 1948 | /* no splice_read */ |
413ef8cb MS |
1949 | }; |
1950 | ||
f5e54d6e | 1951 | static const struct address_space_operations fuse_file_aops = { |
b6aeaded | 1952 | .readpage = fuse_readpage, |
3be5a52b MS |
1953 | .writepage = fuse_writepage, |
1954 | .launder_page = fuse_launder_page, | |
5e6f58a1 NP |
1955 | .write_begin = fuse_write_begin, |
1956 | .write_end = fuse_write_end, | |
db50b96c | 1957 | .readpages = fuse_readpages, |
3be5a52b | 1958 | .set_page_dirty = __set_page_dirty_nobuffers, |
b2d2272f | 1959 | .bmap = fuse_bmap, |
b6aeaded MS |
1960 | }; |
1961 | ||
1962 | void fuse_init_file_inode(struct inode *inode) | |
1963 | { | |
45323fb7 MS |
1964 | inode->i_fop = &fuse_file_operations; |
1965 | inode->i_data.a_ops = &fuse_file_aops; | |
b6aeaded | 1966 | } |