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Miklos Szeredi334f4852005-09-09 13:10:27 -07001/*
2 FUSE: Filesystem in Userspace
Miklos Szeredi1729a162008-11-26 12:03:54 +01003 Copyright (C) 2001-2008 Miklos Szeredi <miklos@szeredi.hu>
Miklos Szeredi334f4852005-09-09 13:10:27 -07004
5 This program can be distributed under the terms of the GNU GPL.
6 See the file COPYING.
7*/
8
9#include "fuse_i.h"
10
11#include <linux/init.h>
12#include <linux/module.h>
13#include <linux/poll.h>
14#include <linux/uio.h>
15#include <linux/miscdevice.h>
16#include <linux/pagemap.h>
17#include <linux/file.h>
18#include <linux/slab.h>
Miklos Szeredidd3bb142010-05-25 15:06:06 +020019#include <linux/pipe_fs_i.h>
Miklos Szeredice534fb2010-05-25 15:06:07 +020020#include <linux/swap.h>
21#include <linux/splice.h>
Kent Overstreeta27bb332013-05-07 16:19:08 -070022#include <linux/aio.h>
Miklos Szeredi334f4852005-09-09 13:10:27 -070023
24MODULE_ALIAS_MISCDEV(FUSE_MINOR);
Kay Sievers578454f2010-05-20 18:07:20 +020025MODULE_ALIAS("devname:fuse");
Miklos Szeredi334f4852005-09-09 13:10:27 -070026
Christoph Lametere18b8902006-12-06 20:33:20 -080027static struct kmem_cache *fuse_req_cachep;
Miklos Szeredi334f4852005-09-09 13:10:27 -070028
Miklos Szeredi8bfc0162006-01-16 22:14:28 -080029static struct fuse_conn *fuse_get_conn(struct file *file)
Miklos Szeredi334f4852005-09-09 13:10:27 -070030{
Miklos Szeredi0720b312006-04-10 22:54:55 -070031 /*
32 * Lockless access is OK, because file->private data is set
33 * once during mount and is valid until the file is released.
34 */
35 return file->private_data;
Miklos Szeredi334f4852005-09-09 13:10:27 -070036}
37
Maxim Patlasov4250c062012-10-26 19:48:07 +040038static void fuse_request_init(struct fuse_req *req, struct page **pages,
Maxim Patlasovb2430d72012-10-26 19:49:24 +040039 struct fuse_page_desc *page_descs,
Maxim Patlasov4250c062012-10-26 19:48:07 +040040 unsigned npages)
Miklos Szeredi334f4852005-09-09 13:10:27 -070041{
42 memset(req, 0, sizeof(*req));
Maxim Patlasov4250c062012-10-26 19:48:07 +040043 memset(pages, 0, sizeof(*pages) * npages);
Maxim Patlasovb2430d72012-10-26 19:49:24 +040044 memset(page_descs, 0, sizeof(*page_descs) * npages);
Miklos Szeredi334f4852005-09-09 13:10:27 -070045 INIT_LIST_HEAD(&req->list);
Miklos Szeredia4d27e72006-06-25 05:48:54 -070046 INIT_LIST_HEAD(&req->intr_entry);
Miklos Szeredi334f4852005-09-09 13:10:27 -070047 init_waitqueue_head(&req->waitq);
48 atomic_set(&req->count, 1);
Maxim Patlasov4250c062012-10-26 19:48:07 +040049 req->pages = pages;
Maxim Patlasovb2430d72012-10-26 19:49:24 +040050 req->page_descs = page_descs;
Maxim Patlasov4250c062012-10-26 19:48:07 +040051 req->max_pages = npages;
Miklos Szeredi334f4852005-09-09 13:10:27 -070052}
53
Maxim Patlasov4250c062012-10-26 19:48:07 +040054static struct fuse_req *__fuse_request_alloc(unsigned npages, gfp_t flags)
Miklos Szeredi334f4852005-09-09 13:10:27 -070055{
Maxim Patlasov4250c062012-10-26 19:48:07 +040056 struct fuse_req *req = kmem_cache_alloc(fuse_req_cachep, flags);
57 if (req) {
58 struct page **pages;
Maxim Patlasovb2430d72012-10-26 19:49:24 +040059 struct fuse_page_desc *page_descs;
Maxim Patlasov4250c062012-10-26 19:48:07 +040060
Maxim Patlasovb2430d72012-10-26 19:49:24 +040061 if (npages <= FUSE_REQ_INLINE_PAGES) {
Maxim Patlasov4250c062012-10-26 19:48:07 +040062 pages = req->inline_pages;
Maxim Patlasovb2430d72012-10-26 19:49:24 +040063 page_descs = req->inline_page_descs;
64 } else {
Maxim Patlasov4250c062012-10-26 19:48:07 +040065 pages = kmalloc(sizeof(struct page *) * npages, flags);
Maxim Patlasovb2430d72012-10-26 19:49:24 +040066 page_descs = kmalloc(sizeof(struct fuse_page_desc) *
67 npages, flags);
68 }
Maxim Patlasov4250c062012-10-26 19:48:07 +040069
Maxim Patlasovb2430d72012-10-26 19:49:24 +040070 if (!pages || !page_descs) {
71 kfree(pages);
72 kfree(page_descs);
Maxim Patlasov4250c062012-10-26 19:48:07 +040073 kmem_cache_free(fuse_req_cachep, req);
74 return NULL;
75 }
76
Maxim Patlasovb2430d72012-10-26 19:49:24 +040077 fuse_request_init(req, pages, page_descs, npages);
Maxim Patlasov4250c062012-10-26 19:48:07 +040078 }
Miklos Szeredi334f4852005-09-09 13:10:27 -070079 return req;
80}
Maxim Patlasov4250c062012-10-26 19:48:07 +040081
82struct fuse_req *fuse_request_alloc(unsigned npages)
83{
84 return __fuse_request_alloc(npages, GFP_KERNEL);
85}
Tejun Heo08cbf542009-04-14 10:54:53 +090086EXPORT_SYMBOL_GPL(fuse_request_alloc);
Miklos Szeredi334f4852005-09-09 13:10:27 -070087
Maxim Patlasov4250c062012-10-26 19:48:07 +040088struct fuse_req *fuse_request_alloc_nofs(unsigned npages)
Miklos Szeredi3be5a522008-04-30 00:54:41 -070089{
Maxim Patlasov4250c062012-10-26 19:48:07 +040090 return __fuse_request_alloc(npages, GFP_NOFS);
Miklos Szeredi3be5a522008-04-30 00:54:41 -070091}
92
Miklos Szeredi334f4852005-09-09 13:10:27 -070093void fuse_request_free(struct fuse_req *req)
94{
Maxim Patlasovb2430d72012-10-26 19:49:24 +040095 if (req->pages != req->inline_pages) {
Maxim Patlasov4250c062012-10-26 19:48:07 +040096 kfree(req->pages);
Maxim Patlasovb2430d72012-10-26 19:49:24 +040097 kfree(req->page_descs);
98 }
Miklos Szeredi334f4852005-09-09 13:10:27 -070099 kmem_cache_free(fuse_req_cachep, req);
100}
101
Miklos Szeredi8bfc0162006-01-16 22:14:28 -0800102static void block_sigs(sigset_t *oldset)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700103{
104 sigset_t mask;
105
106 siginitsetinv(&mask, sigmask(SIGKILL));
107 sigprocmask(SIG_BLOCK, &mask, oldset);
108}
109
Miklos Szeredi8bfc0162006-01-16 22:14:28 -0800110static void restore_sigs(sigset_t *oldset)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700111{
112 sigprocmask(SIG_SETMASK, oldset, NULL);
113}
114
Maxim Patlasov36cf66e2012-12-14 19:20:51 +0400115void __fuse_get_request(struct fuse_req *req)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700116{
117 atomic_inc(&req->count);
118}
119
120/* Must be called with > 1 refcount */
121static void __fuse_put_request(struct fuse_req *req)
122{
123 BUG_ON(atomic_read(&req->count) < 2);
124 atomic_dec(&req->count);
125}
126
Miklos Szeredi33649c92006-06-25 05:48:52 -0700127static void fuse_req_init_context(struct fuse_req *req)
128{
Eric W. Biederman499dcf22012-02-07 16:26:03 -0800129 req->in.h.uid = from_kuid_munged(&init_user_ns, current_fsuid());
130 req->in.h.gid = from_kgid_munged(&init_user_ns, current_fsgid());
Miklos Szeredi33649c92006-06-25 05:48:52 -0700131 req->in.h.pid = current->pid;
132}
133
Maxim Patlasov0aada882013-03-21 18:02:28 +0400134static bool fuse_block_alloc(struct fuse_conn *fc, bool for_background)
135{
136 return !fc->initialized || (for_background && fc->blocked);
137}
138
Maxim Patlasov8b41e672013-03-21 18:02:04 +0400139static struct fuse_req *__fuse_get_req(struct fuse_conn *fc, unsigned npages,
140 bool for_background)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700141{
Miklos Szeredi08a53cd2006-04-10 22:54:59 -0700142 struct fuse_req *req;
Miklos Szeredi08a53cd2006-04-10 22:54:59 -0700143 int err;
Miklos Szeredi9bc5ddd2006-04-11 21:16:09 +0200144 atomic_inc(&fc->num_waiting);
Maxim Patlasov0aada882013-03-21 18:02:28 +0400145
146 if (fuse_block_alloc(fc, for_background)) {
147 sigset_t oldset;
148 int intr;
149
150 block_sigs(&oldset);
Maxim Patlasov722d2be2013-03-21 18:02:36 +0400151 intr = wait_event_interruptible_exclusive(fc->blocked_waitq,
Maxim Patlasov0aada882013-03-21 18:02:28 +0400152 !fuse_block_alloc(fc, for_background));
153 restore_sigs(&oldset);
154 err = -EINTR;
155 if (intr)
156 goto out;
157 }
Miklos Szeredi08a53cd2006-04-10 22:54:59 -0700158
Miklos Szeredi51eb01e2006-06-25 05:48:50 -0700159 err = -ENOTCONN;
160 if (!fc->connected)
161 goto out;
162
Maxim Patlasovb111c8c2012-10-26 19:48:30 +0400163 req = fuse_request_alloc(npages);
Miklos Szeredi9bc5ddd2006-04-11 21:16:09 +0200164 err = -ENOMEM;
Maxim Patlasov722d2be2013-03-21 18:02:36 +0400165 if (!req) {
166 if (for_background)
167 wake_up(&fc->blocked_waitq);
Miklos Szeredi9bc5ddd2006-04-11 21:16:09 +0200168 goto out;
Maxim Patlasov722d2be2013-03-21 18:02:36 +0400169 }
Miklos Szeredi334f4852005-09-09 13:10:27 -0700170
Miklos Szeredi33649c92006-06-25 05:48:52 -0700171 fuse_req_init_context(req);
Miklos Szeredi9bc5ddd2006-04-11 21:16:09 +0200172 req->waiting = 1;
Maxim Patlasov8b41e672013-03-21 18:02:04 +0400173 req->background = for_background;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700174 return req;
Miklos Szeredi9bc5ddd2006-04-11 21:16:09 +0200175
176 out:
177 atomic_dec(&fc->num_waiting);
178 return ERR_PTR(err);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700179}
Maxim Patlasov8b41e672013-03-21 18:02:04 +0400180
181struct fuse_req *fuse_get_req(struct fuse_conn *fc, unsigned npages)
182{
183 return __fuse_get_req(fc, npages, false);
184}
Tejun Heo08cbf542009-04-14 10:54:53 +0900185EXPORT_SYMBOL_GPL(fuse_get_req);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700186
Maxim Patlasov8b41e672013-03-21 18:02:04 +0400187struct fuse_req *fuse_get_req_for_background(struct fuse_conn *fc,
188 unsigned npages)
189{
190 return __fuse_get_req(fc, npages, true);
191}
192EXPORT_SYMBOL_GPL(fuse_get_req_for_background);
193
Miklos Szeredi33649c92006-06-25 05:48:52 -0700194/*
195 * Return request in fuse_file->reserved_req. However that may
196 * currently be in use. If that is the case, wait for it to become
197 * available.
198 */
199static struct fuse_req *get_reserved_req(struct fuse_conn *fc,
200 struct file *file)
201{
202 struct fuse_req *req = NULL;
203 struct fuse_file *ff = file->private_data;
204
205 do {
Miklos Szeredide5e3de2007-10-16 23:31:00 -0700206 wait_event(fc->reserved_req_waitq, ff->reserved_req);
Miklos Szeredi33649c92006-06-25 05:48:52 -0700207 spin_lock(&fc->lock);
208 if (ff->reserved_req) {
209 req = ff->reserved_req;
210 ff->reserved_req = NULL;
Al Virocb0942b2012-08-27 14:48:26 -0400211 req->stolen_file = get_file(file);
Miklos Szeredi33649c92006-06-25 05:48:52 -0700212 }
213 spin_unlock(&fc->lock);
214 } while (!req);
215
216 return req;
217}
218
219/*
220 * Put stolen request back into fuse_file->reserved_req
221 */
222static void put_reserved_req(struct fuse_conn *fc, struct fuse_req *req)
223{
224 struct file *file = req->stolen_file;
225 struct fuse_file *ff = file->private_data;
226
227 spin_lock(&fc->lock);
Maxim Patlasovb2430d72012-10-26 19:49:24 +0400228 fuse_request_init(req, req->pages, req->page_descs, req->max_pages);
Miklos Szeredi33649c92006-06-25 05:48:52 -0700229 BUG_ON(ff->reserved_req);
230 ff->reserved_req = req;
Miklos Szeredide5e3de2007-10-16 23:31:00 -0700231 wake_up_all(&fc->reserved_req_waitq);
Miklos Szeredi33649c92006-06-25 05:48:52 -0700232 spin_unlock(&fc->lock);
233 fput(file);
234}
235
236/*
237 * Gets a requests for a file operation, always succeeds
238 *
239 * This is used for sending the FLUSH request, which must get to
240 * userspace, due to POSIX locks which may need to be unlocked.
241 *
242 * If allocation fails due to OOM, use the reserved request in
243 * fuse_file.
244 *
245 * This is very unlikely to deadlock accidentally, since the
246 * filesystem should not have it's own file open. If deadlock is
247 * intentional, it can still be broken by "aborting" the filesystem.
248 */
Maxim Patlasovb111c8c2012-10-26 19:48:30 +0400249struct fuse_req *fuse_get_req_nofail_nopages(struct fuse_conn *fc,
250 struct file *file)
Miklos Szeredi33649c92006-06-25 05:48:52 -0700251{
252 struct fuse_req *req;
253
254 atomic_inc(&fc->num_waiting);
Maxim Patlasov0aada882013-03-21 18:02:28 +0400255 wait_event(fc->blocked_waitq, fc->initialized);
Maxim Patlasovb111c8c2012-10-26 19:48:30 +0400256 req = fuse_request_alloc(0);
Miklos Szeredi33649c92006-06-25 05:48:52 -0700257 if (!req)
258 req = get_reserved_req(fc, file);
259
260 fuse_req_init_context(req);
261 req->waiting = 1;
Maxim Patlasov8b41e672013-03-21 18:02:04 +0400262 req->background = 0;
Miklos Szeredi33649c92006-06-25 05:48:52 -0700263 return req;
264}
265
Miklos Szeredi334f4852005-09-09 13:10:27 -0700266void fuse_put_request(struct fuse_conn *fc, struct fuse_req *req)
267{
Miklos Szeredi7128ec22006-02-04 23:27:40 -0800268 if (atomic_dec_and_test(&req->count)) {
Maxim Patlasov722d2be2013-03-21 18:02:36 +0400269 if (unlikely(req->background)) {
270 /*
271 * We get here in the unlikely case that a background
272 * request was allocated but not sent
273 */
274 spin_lock(&fc->lock);
275 if (!fc->blocked)
276 wake_up(&fc->blocked_waitq);
277 spin_unlock(&fc->lock);
278 }
279
Miklos Szeredi9bc5ddd2006-04-11 21:16:09 +0200280 if (req->waiting)
281 atomic_dec(&fc->num_waiting);
Miklos Szeredi33649c92006-06-25 05:48:52 -0700282
283 if (req->stolen_file)
284 put_reserved_req(fc, req);
285 else
286 fuse_request_free(req);
Miklos Szeredi7128ec22006-02-04 23:27:40 -0800287 }
288}
Tejun Heo08cbf542009-04-14 10:54:53 +0900289EXPORT_SYMBOL_GPL(fuse_put_request);
Miklos Szeredi7128ec22006-02-04 23:27:40 -0800290
Miklos Szeredid12def12008-02-06 01:38:39 -0800291static unsigned len_args(unsigned numargs, struct fuse_arg *args)
292{
293 unsigned nbytes = 0;
294 unsigned i;
295
296 for (i = 0; i < numargs; i++)
297 nbytes += args[i].size;
298
299 return nbytes;
300}
301
302static u64 fuse_get_unique(struct fuse_conn *fc)
303{
304 fc->reqctr++;
305 /* zero is special */
306 if (fc->reqctr == 0)
307 fc->reqctr = 1;
308
309 return fc->reqctr;
310}
311
312static void queue_request(struct fuse_conn *fc, struct fuse_req *req)
313{
Miklos Szeredid12def12008-02-06 01:38:39 -0800314 req->in.h.len = sizeof(struct fuse_in_header) +
315 len_args(req->in.numargs, (struct fuse_arg *) req->in.args);
316 list_add_tail(&req->list, &fc->pending);
317 req->state = FUSE_REQ_PENDING;
318 if (!req->waiting) {
319 req->waiting = 1;
320 atomic_inc(&fc->num_waiting);
321 }
322 wake_up(&fc->waitq);
323 kill_fasync(&fc->fasync, SIGIO, POLL_IN);
324}
325
Miklos Szeredi07e77dc2010-12-07 20:16:56 +0100326void fuse_queue_forget(struct fuse_conn *fc, struct fuse_forget_link *forget,
327 u64 nodeid, u64 nlookup)
328{
Miklos Szeredi02c048b2010-12-07 20:16:56 +0100329 forget->forget_one.nodeid = nodeid;
330 forget->forget_one.nlookup = nlookup;
Miklos Szeredi07e77dc2010-12-07 20:16:56 +0100331
332 spin_lock(&fc->lock);
Miklos Szeredi5dfcc872011-09-12 09:38:03 +0200333 if (fc->connected) {
334 fc->forget_list_tail->next = forget;
335 fc->forget_list_tail = forget;
336 wake_up(&fc->waitq);
337 kill_fasync(&fc->fasync, SIGIO, POLL_IN);
338 } else {
339 kfree(forget);
340 }
Miklos Szeredi07e77dc2010-12-07 20:16:56 +0100341 spin_unlock(&fc->lock);
342}
343
Miklos Szeredid12def12008-02-06 01:38:39 -0800344static void flush_bg_queue(struct fuse_conn *fc)
345{
Csaba Henk7a6d3c82009-07-01 17:28:41 -0700346 while (fc->active_background < fc->max_background &&
Miklos Szeredid12def12008-02-06 01:38:39 -0800347 !list_empty(&fc->bg_queue)) {
348 struct fuse_req *req;
349
350 req = list_entry(fc->bg_queue.next, struct fuse_req, list);
351 list_del(&req->list);
352 fc->active_background++;
Miklos Szeredi2d45ba32010-07-12 14:41:40 +0200353 req->in.h.unique = fuse_get_unique(fc);
Miklos Szeredid12def12008-02-06 01:38:39 -0800354 queue_request(fc, req);
355 }
356}
357
Miklos Szeredi6dbbcb12006-04-26 10:49:06 +0200358/*
Miklos Szeredi334f4852005-09-09 13:10:27 -0700359 * This function is called when a request is finished. Either a reply
Miklos Szeredif9a28422006-06-25 05:48:53 -0700360 * has arrived or it was aborted (and not yet sent) or some error
Miklos Szeredif43b1552006-01-16 22:14:26 -0800361 * occurred during communication with userspace, or the device file
Miklos Szeredi51eb01e2006-06-25 05:48:50 -0700362 * was closed. The requester thread is woken up (if still waiting),
363 * the 'end' callback is called if given, else the reference to the
364 * request is released
Miklos Szeredi7128ec22006-02-04 23:27:40 -0800365 *
Miklos Szeredid7133112006-04-10 22:54:55 -0700366 * Called with fc->lock, unlocks it
Miklos Szeredi334f4852005-09-09 13:10:27 -0700367 */
368static void request_end(struct fuse_conn *fc, struct fuse_req *req)
Miklos Szeredib9ca67b2010-09-07 13:42:41 +0200369__releases(fc->lock)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700370{
Miklos Szeredi51eb01e2006-06-25 05:48:50 -0700371 void (*end) (struct fuse_conn *, struct fuse_req *) = req->end;
372 req->end = NULL;
Miklos Szeredid77a1d52006-01-16 22:14:31 -0800373 list_del(&req->list);
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700374 list_del(&req->intr_entry);
Miklos Szeredi83cfd492006-01-16 22:14:31 -0800375 req->state = FUSE_REQ_FINISHED;
Miklos Szeredi51eb01e2006-06-25 05:48:50 -0700376 if (req->background) {
Maxim Patlasov722d2be2013-03-21 18:02:36 +0400377 req->background = 0;
378
379 if (fc->num_background == fc->max_background)
Miklos Szeredi51eb01e2006-06-25 05:48:50 -0700380 fc->blocked = 0;
Maxim Patlasov722d2be2013-03-21 18:02:36 +0400381
382 /* Wake up next waiter, if any */
Miklos Szeredi3c18ef82013-04-17 21:50:58 +0200383 if (!fc->blocked && waitqueue_active(&fc->blocked_waitq))
Maxim Patlasov722d2be2013-03-21 18:02:36 +0400384 wake_up(&fc->blocked_waitq);
385
Csaba Henk7a6d3c82009-07-01 17:28:41 -0700386 if (fc->num_background == fc->congestion_threshold &&
Tejun Heoa325f9b2009-04-14 10:54:52 +0900387 fc->connected && fc->bdi_initialized) {
Jens Axboe8aa7e842009-07-09 14:52:32 +0200388 clear_bdi_congested(&fc->bdi, BLK_RW_SYNC);
389 clear_bdi_congested(&fc->bdi, BLK_RW_ASYNC);
Miklos Szeredif92b99b2007-10-16 23:30:59 -0700390 }
Miklos Szeredi51eb01e2006-06-25 05:48:50 -0700391 fc->num_background--;
Miklos Szeredid12def12008-02-06 01:38:39 -0800392 fc->active_background--;
393 flush_bg_queue(fc);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700394 }
Miklos Szeredi51eb01e2006-06-25 05:48:50 -0700395 spin_unlock(&fc->lock);
Miklos Szeredi51eb01e2006-06-25 05:48:50 -0700396 wake_up(&req->waitq);
397 if (end)
398 end(fc, req);
Tejun Heoe9bb09d2008-11-26 12:03:54 +0100399 fuse_put_request(fc, req);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700400}
401
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700402static void wait_answer_interruptible(struct fuse_conn *fc,
403 struct fuse_req *req)
Miklos Szeredib9ca67b2010-09-07 13:42:41 +0200404__releases(fc->lock)
405__acquires(fc->lock)
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700406{
407 if (signal_pending(current))
408 return;
409
410 spin_unlock(&fc->lock);
411 wait_event_interruptible(req->waitq, req->state == FUSE_REQ_FINISHED);
412 spin_lock(&fc->lock);
413}
414
415static void queue_interrupt(struct fuse_conn *fc, struct fuse_req *req)
416{
417 list_add_tail(&req->intr_entry, &fc->interrupts);
418 wake_up(&fc->waitq);
419 kill_fasync(&fc->fasync, SIGIO, POLL_IN);
420}
421
Miklos Szeredi7c352bd2005-09-09 13:10:39 -0700422static void request_wait_answer(struct fuse_conn *fc, struct fuse_req *req)
Miklos Szeredib9ca67b2010-09-07 13:42:41 +0200423__releases(fc->lock)
424__acquires(fc->lock)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700425{
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700426 if (!fc->no_interrupt) {
427 /* Any signal may interrupt this */
428 wait_answer_interruptible(fc, req);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700429
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700430 if (req->aborted)
431 goto aborted;
432 if (req->state == FUSE_REQ_FINISHED)
433 return;
434
435 req->interrupted = 1;
436 if (req->state == FUSE_REQ_SENT)
437 queue_interrupt(fc, req);
438 }
439
Miklos Szeredia131de02007-10-16 23:31:04 -0700440 if (!req->force) {
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700441 sigset_t oldset;
442
443 /* Only fatal signals may interrupt this */
Miklos Szeredi51eb01e2006-06-25 05:48:50 -0700444 block_sigs(&oldset);
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700445 wait_answer_interruptible(fc, req);
Miklos Szeredi51eb01e2006-06-25 05:48:50 -0700446 restore_sigs(&oldset);
Miklos Szeredia131de02007-10-16 23:31:04 -0700447
448 if (req->aborted)
449 goto aborted;
450 if (req->state == FUSE_REQ_FINISHED)
451 return;
452
453 /* Request is not yet in userspace, bail out */
454 if (req->state == FUSE_REQ_PENDING) {
455 list_del(&req->list);
456 __fuse_put_request(req);
457 req->out.h.error = -EINTR;
458 return;
459 }
Miklos Szeredi51eb01e2006-06-25 05:48:50 -0700460 }
Miklos Szeredi334f4852005-09-09 13:10:27 -0700461
Miklos Szeredia131de02007-10-16 23:31:04 -0700462 /*
463 * Either request is already in userspace, or it was forced.
464 * Wait it out.
465 */
466 spin_unlock(&fc->lock);
467 wait_event(req->waitq, req->state == FUSE_REQ_FINISHED);
468 spin_lock(&fc->lock);
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700469
Miklos Szeredia131de02007-10-16 23:31:04 -0700470 if (!req->aborted)
471 return;
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700472
473 aborted:
Miklos Szeredia131de02007-10-16 23:31:04 -0700474 BUG_ON(req->state != FUSE_REQ_FINISHED);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700475 if (req->locked) {
476 /* This is uninterruptible sleep, because data is
477 being copied to/from the buffers of req. During
478 locked state, there mustn't be any filesystem
479 operation (e.g. page fault), since that could lead
480 to deadlock */
Miklos Szeredid7133112006-04-10 22:54:55 -0700481 spin_unlock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700482 wait_event(req->waitq, !req->locked);
Miklos Szeredid7133112006-04-10 22:54:55 -0700483 spin_lock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700484 }
Miklos Szeredi334f4852005-09-09 13:10:27 -0700485}
486
Eric Wong6a4e9222013-02-04 13:04:44 +0000487static void __fuse_request_send(struct fuse_conn *fc, struct fuse_req *req)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700488{
Maxim Patlasov8b41e672013-03-21 18:02:04 +0400489 BUG_ON(req->background);
Miklos Szeredid7133112006-04-10 22:54:55 -0700490 spin_lock(&fc->lock);
Miklos Szeredi1e9a4ed2005-09-09 13:10:31 -0700491 if (!fc->connected)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700492 req->out.h.error = -ENOTCONN;
493 else if (fc->conn_error)
494 req->out.h.error = -ECONNREFUSED;
495 else {
Miklos Szeredi2d45ba32010-07-12 14:41:40 +0200496 req->in.h.unique = fuse_get_unique(fc);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700497 queue_request(fc, req);
498 /* acquire extra reference, since request is still needed
499 after request_end() */
500 __fuse_get_request(req);
501
Miklos Szeredi7c352bd2005-09-09 13:10:39 -0700502 request_wait_answer(fc, req);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700503 }
Miklos Szeredid7133112006-04-10 22:54:55 -0700504 spin_unlock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700505}
Eric Wong6a4e9222013-02-04 13:04:44 +0000506
507void fuse_request_send(struct fuse_conn *fc, struct fuse_req *req)
508{
509 req->isreply = 1;
510 __fuse_request_send(fc, req);
511}
Tejun Heo08cbf542009-04-14 10:54:53 +0900512EXPORT_SYMBOL_GPL(fuse_request_send);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700513
Tejun Heob93f8582008-11-26 12:03:55 +0100514static void fuse_request_send_nowait_locked(struct fuse_conn *fc,
515 struct fuse_req *req)
Miklos Szeredid12def12008-02-06 01:38:39 -0800516{
Maxim Patlasov8b41e672013-03-21 18:02:04 +0400517 BUG_ON(!req->background);
Miklos Szeredid12def12008-02-06 01:38:39 -0800518 fc->num_background++;
Csaba Henk7a6d3c82009-07-01 17:28:41 -0700519 if (fc->num_background == fc->max_background)
Miklos Szeredid12def12008-02-06 01:38:39 -0800520 fc->blocked = 1;
Csaba Henk7a6d3c82009-07-01 17:28:41 -0700521 if (fc->num_background == fc->congestion_threshold &&
Tejun Heoa325f9b2009-04-14 10:54:52 +0900522 fc->bdi_initialized) {
Jens Axboe8aa7e842009-07-09 14:52:32 +0200523 set_bdi_congested(&fc->bdi, BLK_RW_SYNC);
524 set_bdi_congested(&fc->bdi, BLK_RW_ASYNC);
Miklos Szeredid12def12008-02-06 01:38:39 -0800525 }
526 list_add_tail(&req->list, &fc->bg_queue);
527 flush_bg_queue(fc);
528}
529
Tejun Heob93f8582008-11-26 12:03:55 +0100530static void fuse_request_send_nowait(struct fuse_conn *fc, struct fuse_req *req)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700531{
Miklos Szeredid7133112006-04-10 22:54:55 -0700532 spin_lock(&fc->lock);
Miklos Szeredi1e9a4ed2005-09-09 13:10:31 -0700533 if (fc->connected) {
Tejun Heob93f8582008-11-26 12:03:55 +0100534 fuse_request_send_nowait_locked(fc, req);
Miklos Szeredid7133112006-04-10 22:54:55 -0700535 spin_unlock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700536 } else {
537 req->out.h.error = -ENOTCONN;
538 request_end(fc, req);
539 }
540}
541
Tejun Heob93f8582008-11-26 12:03:55 +0100542void fuse_request_send_background(struct fuse_conn *fc, struct fuse_req *req)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700543{
544 req->isreply = 1;
Tejun Heob93f8582008-11-26 12:03:55 +0100545 fuse_request_send_nowait(fc, req);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700546}
Tejun Heo08cbf542009-04-14 10:54:53 +0900547EXPORT_SYMBOL_GPL(fuse_request_send_background);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700548
Miklos Szeredi2d45ba32010-07-12 14:41:40 +0200549static int fuse_request_send_notify_reply(struct fuse_conn *fc,
550 struct fuse_req *req, u64 unique)
551{
552 int err = -ENODEV;
553
554 req->isreply = 0;
555 req->in.h.unique = unique;
556 spin_lock(&fc->lock);
557 if (fc->connected) {
558 queue_request(fc, req);
559 err = 0;
560 }
561 spin_unlock(&fc->lock);
562
563 return err;
564}
565
Miklos Szeredi334f4852005-09-09 13:10:27 -0700566/*
Miklos Szeredi3be5a522008-04-30 00:54:41 -0700567 * Called under fc->lock
568 *
569 * fc->connected must have been checked previously
570 */
Tejun Heob93f8582008-11-26 12:03:55 +0100571void fuse_request_send_background_locked(struct fuse_conn *fc,
572 struct fuse_req *req)
Miklos Szeredi3be5a522008-04-30 00:54:41 -0700573{
574 req->isreply = 1;
Tejun Heob93f8582008-11-26 12:03:55 +0100575 fuse_request_send_nowait_locked(fc, req);
Miklos Szeredi3be5a522008-04-30 00:54:41 -0700576}
577
Anand V. Avati0b05b182012-08-19 08:53:23 -0400578void fuse_force_forget(struct file *file, u64 nodeid)
579{
Al Viro6131ffa2013-02-27 16:59:05 -0500580 struct inode *inode = file_inode(file);
Anand V. Avati0b05b182012-08-19 08:53:23 -0400581 struct fuse_conn *fc = get_fuse_conn(inode);
582 struct fuse_req *req;
583 struct fuse_forget_in inarg;
584
585 memset(&inarg, 0, sizeof(inarg));
586 inarg.nlookup = 1;
Maxim Patlasovb111c8c2012-10-26 19:48:30 +0400587 req = fuse_get_req_nofail_nopages(fc, file);
Anand V. Avati0b05b182012-08-19 08:53:23 -0400588 req->in.h.opcode = FUSE_FORGET;
589 req->in.h.nodeid = nodeid;
590 req->in.numargs = 1;
591 req->in.args[0].size = sizeof(inarg);
592 req->in.args[0].value = &inarg;
593 req->isreply = 0;
Eric Wong6a4e9222013-02-04 13:04:44 +0000594 __fuse_request_send(fc, req);
595 /* ignore errors */
596 fuse_put_request(fc, req);
Anand V. Avati0b05b182012-08-19 08:53:23 -0400597}
598
Miklos Szeredi3be5a522008-04-30 00:54:41 -0700599/*
Miklos Szeredi334f4852005-09-09 13:10:27 -0700600 * Lock the request. Up to the next unlock_request() there mustn't be
601 * anything that could cause a page-fault. If the request was already
Miklos Szeredif9a28422006-06-25 05:48:53 -0700602 * aborted bail out.
Miklos Szeredi334f4852005-09-09 13:10:27 -0700603 */
Miklos Szeredid7133112006-04-10 22:54:55 -0700604static int lock_request(struct fuse_conn *fc, struct fuse_req *req)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700605{
606 int err = 0;
607 if (req) {
Miklos Szeredid7133112006-04-10 22:54:55 -0700608 spin_lock(&fc->lock);
Miklos Szeredif9a28422006-06-25 05:48:53 -0700609 if (req->aborted)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700610 err = -ENOENT;
611 else
612 req->locked = 1;
Miklos Szeredid7133112006-04-10 22:54:55 -0700613 spin_unlock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700614 }
615 return err;
616}
617
618/*
Miklos Szeredif9a28422006-06-25 05:48:53 -0700619 * Unlock request. If it was aborted during being locked, the
Miklos Szeredi334f4852005-09-09 13:10:27 -0700620 * requester thread is currently waiting for it to be unlocked, so
621 * wake it up.
622 */
Miklos Szeredid7133112006-04-10 22:54:55 -0700623static void unlock_request(struct fuse_conn *fc, struct fuse_req *req)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700624{
625 if (req) {
Miklos Szeredid7133112006-04-10 22:54:55 -0700626 spin_lock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700627 req->locked = 0;
Miklos Szeredif9a28422006-06-25 05:48:53 -0700628 if (req->aborted)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700629 wake_up(&req->waitq);
Miklos Szeredid7133112006-04-10 22:54:55 -0700630 spin_unlock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700631 }
632}
633
634struct fuse_copy_state {
Miklos Szeredid7133112006-04-10 22:54:55 -0700635 struct fuse_conn *fc;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700636 int write;
637 struct fuse_req *req;
638 const struct iovec *iov;
Miklos Szeredidd3bb142010-05-25 15:06:06 +0200639 struct pipe_buffer *pipebufs;
640 struct pipe_buffer *currbuf;
641 struct pipe_inode_info *pipe;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700642 unsigned long nr_segs;
643 unsigned long seglen;
644 unsigned long addr;
645 struct page *pg;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700646 unsigned len;
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200647 unsigned offset;
Miklos Szeredice534fb2010-05-25 15:06:07 +0200648 unsigned move_pages:1;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700649};
650
Miklos Szeredid7133112006-04-10 22:54:55 -0700651static void fuse_copy_init(struct fuse_copy_state *cs, struct fuse_conn *fc,
Miklos Szeredic3021622010-05-25 15:06:07 +0200652 int write,
Miklos Szeredid7133112006-04-10 22:54:55 -0700653 const struct iovec *iov, unsigned long nr_segs)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700654{
655 memset(cs, 0, sizeof(*cs));
Miklos Szeredid7133112006-04-10 22:54:55 -0700656 cs->fc = fc;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700657 cs->write = write;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700658 cs->iov = iov;
659 cs->nr_segs = nr_segs;
660}
661
662/* Unmap and put previous page of userspace buffer */
Miklos Szeredi8bfc0162006-01-16 22:14:28 -0800663static void fuse_copy_finish(struct fuse_copy_state *cs)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700664{
Miklos Szeredidd3bb142010-05-25 15:06:06 +0200665 if (cs->currbuf) {
666 struct pipe_buffer *buf = cs->currbuf;
667
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200668 if (cs->write)
Miklos Szeredic3021622010-05-25 15:06:07 +0200669 buf->len = PAGE_SIZE - cs->len;
Miklos Szeredidd3bb142010-05-25 15:06:06 +0200670 cs->currbuf = NULL;
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200671 } else if (cs->pg) {
Miklos Szeredi334f4852005-09-09 13:10:27 -0700672 if (cs->write) {
673 flush_dcache_page(cs->pg);
674 set_page_dirty_lock(cs->pg);
675 }
676 put_page(cs->pg);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700677 }
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200678 cs->pg = NULL;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700679}
680
681/*
682 * Get another pagefull of userspace buffer, and map it to kernel
683 * address space, and lock request
684 */
685static int fuse_copy_fill(struct fuse_copy_state *cs)
686{
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200687 struct page *page;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700688 int err;
689
Miklos Szeredid7133112006-04-10 22:54:55 -0700690 unlock_request(cs->fc, cs->req);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700691 fuse_copy_finish(cs);
Miklos Szeredidd3bb142010-05-25 15:06:06 +0200692 if (cs->pipebufs) {
693 struct pipe_buffer *buf = cs->pipebufs;
694
Miklos Szeredic3021622010-05-25 15:06:07 +0200695 if (!cs->write) {
696 err = buf->ops->confirm(cs->pipe, buf);
697 if (err)
698 return err;
Miklos Szeredidd3bb142010-05-25 15:06:06 +0200699
Miklos Szeredic3021622010-05-25 15:06:07 +0200700 BUG_ON(!cs->nr_segs);
701 cs->currbuf = buf;
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200702 cs->pg = buf->page;
703 cs->offset = buf->offset;
Miklos Szeredic3021622010-05-25 15:06:07 +0200704 cs->len = buf->len;
Miklos Szeredic3021622010-05-25 15:06:07 +0200705 cs->pipebufs++;
706 cs->nr_segs--;
707 } else {
Miklos Szeredic3021622010-05-25 15:06:07 +0200708 if (cs->nr_segs == cs->pipe->buffers)
709 return -EIO;
710
711 page = alloc_page(GFP_HIGHUSER);
712 if (!page)
713 return -ENOMEM;
714
715 buf->page = page;
716 buf->offset = 0;
717 buf->len = 0;
718
719 cs->currbuf = buf;
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200720 cs->pg = page;
721 cs->offset = 0;
Miklos Szeredic3021622010-05-25 15:06:07 +0200722 cs->len = PAGE_SIZE;
723 cs->pipebufs++;
724 cs->nr_segs++;
725 }
Miklos Szeredidd3bb142010-05-25 15:06:06 +0200726 } else {
727 if (!cs->seglen) {
728 BUG_ON(!cs->nr_segs);
729 cs->seglen = cs->iov[0].iov_len;
730 cs->addr = (unsigned long) cs->iov[0].iov_base;
731 cs->iov++;
732 cs->nr_segs--;
733 }
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200734 err = get_user_pages_fast(cs->addr, 1, cs->write, &page);
Miklos Szeredidd3bb142010-05-25 15:06:06 +0200735 if (err < 0)
736 return err;
737 BUG_ON(err != 1);
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200738 cs->pg = page;
739 cs->offset = cs->addr % PAGE_SIZE;
740 cs->len = min(PAGE_SIZE - cs->offset, cs->seglen);
Miklos Szeredidd3bb142010-05-25 15:06:06 +0200741 cs->seglen -= cs->len;
742 cs->addr += cs->len;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700743 }
Miklos Szeredi334f4852005-09-09 13:10:27 -0700744
Miklos Szeredid7133112006-04-10 22:54:55 -0700745 return lock_request(cs->fc, cs->req);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700746}
747
748/* Do as much copy to/from userspace buffer as we can */
Miklos Szeredi8bfc0162006-01-16 22:14:28 -0800749static int fuse_copy_do(struct fuse_copy_state *cs, void **val, unsigned *size)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700750{
751 unsigned ncpy = min(*size, cs->len);
752 if (val) {
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200753 void *pgaddr = kmap_atomic(cs->pg);
754 void *buf = pgaddr + cs->offset;
755
Miklos Szeredi334f4852005-09-09 13:10:27 -0700756 if (cs->write)
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200757 memcpy(buf, *val, ncpy);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700758 else
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200759 memcpy(*val, buf, ncpy);
760
761 kunmap_atomic(pgaddr);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700762 *val += ncpy;
763 }
764 *size -= ncpy;
765 cs->len -= ncpy;
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200766 cs->offset += ncpy;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700767 return ncpy;
768}
769
Miklos Szeredice534fb2010-05-25 15:06:07 +0200770static int fuse_check_page(struct page *page)
771{
772 if (page_mapcount(page) ||
773 page->mapping != NULL ||
774 page_count(page) != 1 ||
775 (page->flags & PAGE_FLAGS_CHECK_AT_PREP &
776 ~(1 << PG_locked |
777 1 << PG_referenced |
778 1 << PG_uptodate |
779 1 << PG_lru |
780 1 << PG_active |
781 1 << PG_reclaim))) {
782 printk(KERN_WARNING "fuse: trying to steal weird page\n");
783 printk(KERN_WARNING " page=%p index=%li flags=%08lx, count=%i, mapcount=%i, mapping=%p\n", page, page->index, page->flags, page_count(page), page_mapcount(page), page->mapping);
784 return 1;
785 }
786 return 0;
787}
788
789static int fuse_try_move_page(struct fuse_copy_state *cs, struct page **pagep)
790{
791 int err;
792 struct page *oldpage = *pagep;
793 struct page *newpage;
794 struct pipe_buffer *buf = cs->pipebufs;
Miklos Szeredice534fb2010-05-25 15:06:07 +0200795
796 unlock_request(cs->fc, cs->req);
797 fuse_copy_finish(cs);
798
799 err = buf->ops->confirm(cs->pipe, buf);
800 if (err)
801 return err;
802
803 BUG_ON(!cs->nr_segs);
804 cs->currbuf = buf;
805 cs->len = buf->len;
806 cs->pipebufs++;
807 cs->nr_segs--;
808
809 if (cs->len != PAGE_SIZE)
810 goto out_fallback;
811
812 if (buf->ops->steal(cs->pipe, buf) != 0)
813 goto out_fallback;
814
815 newpage = buf->page;
816
817 if (WARN_ON(!PageUptodate(newpage)))
818 return -EIO;
819
820 ClearPageMappedToDisk(newpage);
821
822 if (fuse_check_page(newpage) != 0)
823 goto out_fallback_unlock;
824
Miklos Szeredice534fb2010-05-25 15:06:07 +0200825 /*
826 * This is a new and locked page, it shouldn't be mapped or
827 * have any special flags on it
828 */
829 if (WARN_ON(page_mapped(oldpage)))
830 goto out_fallback_unlock;
831 if (WARN_ON(page_has_private(oldpage)))
832 goto out_fallback_unlock;
833 if (WARN_ON(PageDirty(oldpage) || PageWriteback(oldpage)))
834 goto out_fallback_unlock;
835 if (WARN_ON(PageMlocked(oldpage)))
836 goto out_fallback_unlock;
837
Miklos Szeredief6a3c62011-03-22 16:30:52 -0700838 err = replace_page_cache_page(oldpage, newpage, GFP_KERNEL);
Miklos Szeredice534fb2010-05-25 15:06:07 +0200839 if (err) {
Miklos Szeredief6a3c62011-03-22 16:30:52 -0700840 unlock_page(newpage);
841 return err;
Miklos Szeredice534fb2010-05-25 15:06:07 +0200842 }
Miklos Szeredief6a3c62011-03-22 16:30:52 -0700843
Miklos Szeredice534fb2010-05-25 15:06:07 +0200844 page_cache_get(newpage);
845
846 if (!(buf->flags & PIPE_BUF_FLAG_LRU))
847 lru_cache_add_file(newpage);
848
849 err = 0;
850 spin_lock(&cs->fc->lock);
851 if (cs->req->aborted)
852 err = -ENOENT;
853 else
854 *pagep = newpage;
855 spin_unlock(&cs->fc->lock);
856
857 if (err) {
858 unlock_page(newpage);
859 page_cache_release(newpage);
860 return err;
861 }
862
863 unlock_page(oldpage);
864 page_cache_release(oldpage);
865 cs->len = 0;
866
867 return 0;
868
869out_fallback_unlock:
870 unlock_page(newpage);
871out_fallback:
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200872 cs->pg = buf->page;
873 cs->offset = buf->offset;
Miklos Szeredice534fb2010-05-25 15:06:07 +0200874
875 err = lock_request(cs->fc, cs->req);
876 if (err)
877 return err;
878
879 return 1;
880}
881
Miklos Szeredic3021622010-05-25 15:06:07 +0200882static int fuse_ref_page(struct fuse_copy_state *cs, struct page *page,
883 unsigned offset, unsigned count)
884{
885 struct pipe_buffer *buf;
886
887 if (cs->nr_segs == cs->pipe->buffers)
888 return -EIO;
889
890 unlock_request(cs->fc, cs->req);
891 fuse_copy_finish(cs);
892
893 buf = cs->pipebufs;
894 page_cache_get(page);
895 buf->page = page;
896 buf->offset = offset;
897 buf->len = count;
898
899 cs->pipebufs++;
900 cs->nr_segs++;
901 cs->len = 0;
902
903 return 0;
904}
905
Miklos Szeredi334f4852005-09-09 13:10:27 -0700906/*
907 * Copy a page in the request to/from the userspace buffer. Must be
908 * done atomically
909 */
Miklos Szeredice534fb2010-05-25 15:06:07 +0200910static int fuse_copy_page(struct fuse_copy_state *cs, struct page **pagep,
Miklos Szeredi8bfc0162006-01-16 22:14:28 -0800911 unsigned offset, unsigned count, int zeroing)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700912{
Miklos Szeredice534fb2010-05-25 15:06:07 +0200913 int err;
914 struct page *page = *pagep;
915
Miklos Szeredib6777c42010-10-26 14:22:27 -0700916 if (page && zeroing && count < PAGE_SIZE)
917 clear_highpage(page);
918
Miklos Szeredi334f4852005-09-09 13:10:27 -0700919 while (count) {
Miklos Szeredic3021622010-05-25 15:06:07 +0200920 if (cs->write && cs->pipebufs && page) {
921 return fuse_ref_page(cs, page, offset, count);
922 } else if (!cs->len) {
Miklos Szeredice534fb2010-05-25 15:06:07 +0200923 if (cs->move_pages && page &&
924 offset == 0 && count == PAGE_SIZE) {
925 err = fuse_try_move_page(cs, pagep);
926 if (err <= 0)
927 return err;
928 } else {
929 err = fuse_copy_fill(cs);
930 if (err)
931 return err;
932 }
Miklos Szeredi1729a162008-11-26 12:03:54 +0100933 }
Miklos Szeredi334f4852005-09-09 13:10:27 -0700934 if (page) {
Cong Wang2408f6e2011-11-25 23:14:30 +0800935 void *mapaddr = kmap_atomic(page);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700936 void *buf = mapaddr + offset;
937 offset += fuse_copy_do(cs, &buf, &count);
Cong Wang2408f6e2011-11-25 23:14:30 +0800938 kunmap_atomic(mapaddr);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700939 } else
940 offset += fuse_copy_do(cs, NULL, &count);
941 }
942 if (page && !cs->write)
943 flush_dcache_page(page);
944 return 0;
945}
946
947/* Copy pages in the request to/from userspace buffer */
948static int fuse_copy_pages(struct fuse_copy_state *cs, unsigned nbytes,
949 int zeroing)
950{
951 unsigned i;
952 struct fuse_req *req = cs->req;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700953
954 for (i = 0; i < req->num_pages && (nbytes || zeroing); i++) {
Miklos Szeredice534fb2010-05-25 15:06:07 +0200955 int err;
Maxim Patlasov85f40ae2012-10-26 19:49:33 +0400956 unsigned offset = req->page_descs[i].offset;
957 unsigned count = min(nbytes, req->page_descs[i].length);
Miklos Szeredice534fb2010-05-25 15:06:07 +0200958
959 err = fuse_copy_page(cs, &req->pages[i], offset, count,
960 zeroing);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700961 if (err)
962 return err;
963
964 nbytes -= count;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700965 }
966 return 0;
967}
968
969/* Copy a single argument in the request to/from userspace buffer */
970static int fuse_copy_one(struct fuse_copy_state *cs, void *val, unsigned size)
971{
972 while (size) {
Miklos Szeredi1729a162008-11-26 12:03:54 +0100973 if (!cs->len) {
974 int err = fuse_copy_fill(cs);
975 if (err)
976 return err;
977 }
Miklos Szeredi334f4852005-09-09 13:10:27 -0700978 fuse_copy_do(cs, &val, &size);
979 }
980 return 0;
981}
982
983/* Copy request arguments to/from userspace buffer */
984static int fuse_copy_args(struct fuse_copy_state *cs, unsigned numargs,
985 unsigned argpages, struct fuse_arg *args,
986 int zeroing)
987{
988 int err = 0;
989 unsigned i;
990
991 for (i = 0; !err && i < numargs; i++) {
992 struct fuse_arg *arg = &args[i];
993 if (i == numargs - 1 && argpages)
994 err = fuse_copy_pages(cs, arg->size, zeroing);
995 else
996 err = fuse_copy_one(cs, arg->value, arg->size);
997 }
998 return err;
999}
1000
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001001static int forget_pending(struct fuse_conn *fc)
1002{
1003 return fc->forget_list_head.next != NULL;
1004}
1005
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001006static int request_pending(struct fuse_conn *fc)
1007{
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001008 return !list_empty(&fc->pending) || !list_empty(&fc->interrupts) ||
1009 forget_pending(fc);
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001010}
1011
Miklos Szeredi334f4852005-09-09 13:10:27 -07001012/* Wait until a request is available on the pending list */
1013static void request_wait(struct fuse_conn *fc)
Miklos Szeredib9ca67b2010-09-07 13:42:41 +02001014__releases(fc->lock)
1015__acquires(fc->lock)
Miklos Szeredi334f4852005-09-09 13:10:27 -07001016{
1017 DECLARE_WAITQUEUE(wait, current);
1018
1019 add_wait_queue_exclusive(&fc->waitq, &wait);
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001020 while (fc->connected && !request_pending(fc)) {
Miklos Szeredi334f4852005-09-09 13:10:27 -07001021 set_current_state(TASK_INTERRUPTIBLE);
1022 if (signal_pending(current))
1023 break;
1024
Miklos Szeredid7133112006-04-10 22:54:55 -07001025 spin_unlock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001026 schedule();
Miklos Szeredid7133112006-04-10 22:54:55 -07001027 spin_lock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001028 }
1029 set_current_state(TASK_RUNNING);
1030 remove_wait_queue(&fc->waitq, &wait);
1031}
1032
1033/*
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001034 * Transfer an interrupt request to userspace
1035 *
1036 * Unlike other requests this is assembled on demand, without a need
1037 * to allocate a separate fuse_req structure.
1038 *
1039 * Called with fc->lock held, releases it
1040 */
Miklos Szeredic3021622010-05-25 15:06:07 +02001041static int fuse_read_interrupt(struct fuse_conn *fc, struct fuse_copy_state *cs,
1042 size_t nbytes, struct fuse_req *req)
Miklos Szeredib9ca67b2010-09-07 13:42:41 +02001043__releases(fc->lock)
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001044{
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001045 struct fuse_in_header ih;
1046 struct fuse_interrupt_in arg;
1047 unsigned reqsize = sizeof(ih) + sizeof(arg);
1048 int err;
1049
1050 list_del_init(&req->intr_entry);
1051 req->intr_unique = fuse_get_unique(fc);
1052 memset(&ih, 0, sizeof(ih));
1053 memset(&arg, 0, sizeof(arg));
1054 ih.len = reqsize;
1055 ih.opcode = FUSE_INTERRUPT;
1056 ih.unique = req->intr_unique;
1057 arg.unique = req->in.h.unique;
1058
1059 spin_unlock(&fc->lock);
Miklos Szeredic3021622010-05-25 15:06:07 +02001060 if (nbytes < reqsize)
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001061 return -EINVAL;
1062
Miklos Szeredic3021622010-05-25 15:06:07 +02001063 err = fuse_copy_one(cs, &ih, sizeof(ih));
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001064 if (!err)
Miklos Szeredic3021622010-05-25 15:06:07 +02001065 err = fuse_copy_one(cs, &arg, sizeof(arg));
1066 fuse_copy_finish(cs);
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001067
1068 return err ? err : reqsize;
1069}
1070
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001071static struct fuse_forget_link *dequeue_forget(struct fuse_conn *fc,
1072 unsigned max,
1073 unsigned *countp)
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001074{
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001075 struct fuse_forget_link *head = fc->forget_list_head.next;
1076 struct fuse_forget_link **newhead = &head;
1077 unsigned count;
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001078
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001079 for (count = 0; *newhead != NULL && count < max; count++)
1080 newhead = &(*newhead)->next;
1081
1082 fc->forget_list_head.next = *newhead;
1083 *newhead = NULL;
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001084 if (fc->forget_list_head.next == NULL)
1085 fc->forget_list_tail = &fc->forget_list_head;
1086
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001087 if (countp != NULL)
1088 *countp = count;
1089
1090 return head;
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001091}
1092
1093static int fuse_read_single_forget(struct fuse_conn *fc,
1094 struct fuse_copy_state *cs,
1095 size_t nbytes)
1096__releases(fc->lock)
1097{
1098 int err;
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001099 struct fuse_forget_link *forget = dequeue_forget(fc, 1, NULL);
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001100 struct fuse_forget_in arg = {
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001101 .nlookup = forget->forget_one.nlookup,
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001102 };
1103 struct fuse_in_header ih = {
1104 .opcode = FUSE_FORGET,
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001105 .nodeid = forget->forget_one.nodeid,
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001106 .unique = fuse_get_unique(fc),
1107 .len = sizeof(ih) + sizeof(arg),
1108 };
1109
1110 spin_unlock(&fc->lock);
1111 kfree(forget);
1112 if (nbytes < ih.len)
1113 return -EINVAL;
1114
1115 err = fuse_copy_one(cs, &ih, sizeof(ih));
1116 if (!err)
1117 err = fuse_copy_one(cs, &arg, sizeof(arg));
1118 fuse_copy_finish(cs);
1119
1120 if (err)
1121 return err;
1122
1123 return ih.len;
1124}
1125
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001126static int fuse_read_batch_forget(struct fuse_conn *fc,
1127 struct fuse_copy_state *cs, size_t nbytes)
1128__releases(fc->lock)
1129{
1130 int err;
1131 unsigned max_forgets;
1132 unsigned count;
1133 struct fuse_forget_link *head;
1134 struct fuse_batch_forget_in arg = { .count = 0 };
1135 struct fuse_in_header ih = {
1136 .opcode = FUSE_BATCH_FORGET,
1137 .unique = fuse_get_unique(fc),
1138 .len = sizeof(ih) + sizeof(arg),
1139 };
1140
1141 if (nbytes < ih.len) {
1142 spin_unlock(&fc->lock);
1143 return -EINVAL;
1144 }
1145
1146 max_forgets = (nbytes - ih.len) / sizeof(struct fuse_forget_one);
1147 head = dequeue_forget(fc, max_forgets, &count);
1148 spin_unlock(&fc->lock);
1149
1150 arg.count = count;
1151 ih.len += count * sizeof(struct fuse_forget_one);
1152 err = fuse_copy_one(cs, &ih, sizeof(ih));
1153 if (!err)
1154 err = fuse_copy_one(cs, &arg, sizeof(arg));
1155
1156 while (head) {
1157 struct fuse_forget_link *forget = head;
1158
1159 if (!err) {
1160 err = fuse_copy_one(cs, &forget->forget_one,
1161 sizeof(forget->forget_one));
1162 }
1163 head = forget->next;
1164 kfree(forget);
1165 }
1166
1167 fuse_copy_finish(cs);
1168
1169 if (err)
1170 return err;
1171
1172 return ih.len;
1173}
1174
1175static int fuse_read_forget(struct fuse_conn *fc, struct fuse_copy_state *cs,
1176 size_t nbytes)
1177__releases(fc->lock)
1178{
1179 if (fc->minor < 16 || fc->forget_list_head.next->next == NULL)
1180 return fuse_read_single_forget(fc, cs, nbytes);
1181 else
1182 return fuse_read_batch_forget(fc, cs, nbytes);
1183}
1184
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001185/*
Miklos Szeredi334f4852005-09-09 13:10:27 -07001186 * Read a single request into the userspace filesystem's buffer. This
1187 * function waits until a request is available, then removes it from
1188 * the pending list and copies request data to userspace buffer. If
Miklos Szeredif9a28422006-06-25 05:48:53 -07001189 * no reply is needed (FORGET) or request has been aborted or there
1190 * was an error during the copying then it's finished by calling
Miklos Szeredi334f4852005-09-09 13:10:27 -07001191 * request_end(). Otherwise add it to the processing list, and set
1192 * the 'sent' flag.
1193 */
Miklos Szeredic3021622010-05-25 15:06:07 +02001194static ssize_t fuse_dev_do_read(struct fuse_conn *fc, struct file *file,
1195 struct fuse_copy_state *cs, size_t nbytes)
Miklos Szeredi334f4852005-09-09 13:10:27 -07001196{
1197 int err;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001198 struct fuse_req *req;
1199 struct fuse_in *in;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001200 unsigned reqsize;
1201
Miklos Szeredi1d3d7522006-01-06 00:19:40 -08001202 restart:
Miklos Szeredid7133112006-04-10 22:54:55 -07001203 spin_lock(&fc->lock);
Jeff Dikee5ac1d12006-04-10 22:54:53 -07001204 err = -EAGAIN;
1205 if ((file->f_flags & O_NONBLOCK) && fc->connected &&
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001206 !request_pending(fc))
Jeff Dikee5ac1d12006-04-10 22:54:53 -07001207 goto err_unlock;
1208
Miklos Szeredi334f4852005-09-09 13:10:27 -07001209 request_wait(fc);
1210 err = -ENODEV;
Miklos Szeredi9ba7cbb2006-01-16 22:14:34 -08001211 if (!fc->connected)
Miklos Szeredi334f4852005-09-09 13:10:27 -07001212 goto err_unlock;
1213 err = -ERESTARTSYS;
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001214 if (!request_pending(fc))
Miklos Szeredi334f4852005-09-09 13:10:27 -07001215 goto err_unlock;
1216
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001217 if (!list_empty(&fc->interrupts)) {
1218 req = list_entry(fc->interrupts.next, struct fuse_req,
1219 intr_entry);
Miklos Szeredic3021622010-05-25 15:06:07 +02001220 return fuse_read_interrupt(fc, cs, nbytes, req);
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001221 }
1222
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001223 if (forget_pending(fc)) {
1224 if (list_empty(&fc->pending) || fc->forget_batch-- > 0)
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001225 return fuse_read_forget(fc, cs, nbytes);
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001226
1227 if (fc->forget_batch <= -8)
1228 fc->forget_batch = 16;
1229 }
1230
Miklos Szeredi334f4852005-09-09 13:10:27 -07001231 req = list_entry(fc->pending.next, struct fuse_req, list);
Miklos Szeredi83cfd492006-01-16 22:14:31 -08001232 req->state = FUSE_REQ_READING;
Miklos Szeredid77a1d52006-01-16 22:14:31 -08001233 list_move(&req->list, &fc->io);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001234
1235 in = &req->in;
Miklos Szeredi1d3d7522006-01-06 00:19:40 -08001236 reqsize = in->h.len;
1237 /* If request is too large, reply with an error and restart the read */
Miklos Szeredic3021622010-05-25 15:06:07 +02001238 if (nbytes < reqsize) {
Miklos Szeredi1d3d7522006-01-06 00:19:40 -08001239 req->out.h.error = -EIO;
1240 /* SETXATTR is special, since it may contain too large data */
1241 if (in->h.opcode == FUSE_SETXATTR)
1242 req->out.h.error = -E2BIG;
1243 request_end(fc, req);
1244 goto restart;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001245 }
Miklos Szeredid7133112006-04-10 22:54:55 -07001246 spin_unlock(&fc->lock);
Miklos Szeredic3021622010-05-25 15:06:07 +02001247 cs->req = req;
1248 err = fuse_copy_one(cs, &in->h, sizeof(in->h));
Miklos Szeredi1d3d7522006-01-06 00:19:40 -08001249 if (!err)
Miklos Szeredic3021622010-05-25 15:06:07 +02001250 err = fuse_copy_args(cs, in->numargs, in->argpages,
Miklos Szeredi1d3d7522006-01-06 00:19:40 -08001251 (struct fuse_arg *) in->args, 0);
Miklos Szeredic3021622010-05-25 15:06:07 +02001252 fuse_copy_finish(cs);
Miklos Szeredid7133112006-04-10 22:54:55 -07001253 spin_lock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001254 req->locked = 0;
Miklos Szeredic9c9d7d2007-10-16 23:31:05 -07001255 if (req->aborted) {
1256 request_end(fc, req);
1257 return -ENODEV;
1258 }
Miklos Szeredi334f4852005-09-09 13:10:27 -07001259 if (err) {
Miklos Szeredic9c9d7d2007-10-16 23:31:05 -07001260 req->out.h.error = -EIO;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001261 request_end(fc, req);
1262 return err;
1263 }
1264 if (!req->isreply)
1265 request_end(fc, req);
1266 else {
Miklos Szeredi83cfd492006-01-16 22:14:31 -08001267 req->state = FUSE_REQ_SENT;
Miklos Szeredid77a1d52006-01-16 22:14:31 -08001268 list_move_tail(&req->list, &fc->processing);
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001269 if (req->interrupted)
1270 queue_interrupt(fc, req);
Miklos Szeredid7133112006-04-10 22:54:55 -07001271 spin_unlock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001272 }
1273 return reqsize;
1274
1275 err_unlock:
Miklos Szeredid7133112006-04-10 22:54:55 -07001276 spin_unlock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001277 return err;
1278}
1279
Miklos Szeredic3021622010-05-25 15:06:07 +02001280static ssize_t fuse_dev_read(struct kiocb *iocb, const struct iovec *iov,
1281 unsigned long nr_segs, loff_t pos)
1282{
1283 struct fuse_copy_state cs;
1284 struct file *file = iocb->ki_filp;
1285 struct fuse_conn *fc = fuse_get_conn(file);
1286 if (!fc)
1287 return -EPERM;
1288
1289 fuse_copy_init(&cs, fc, 1, iov, nr_segs);
1290
1291 return fuse_dev_do_read(fc, file, &cs, iov_length(iov, nr_segs));
1292}
1293
Miklos Szeredic3021622010-05-25 15:06:07 +02001294static ssize_t fuse_dev_splice_read(struct file *in, loff_t *ppos,
1295 struct pipe_inode_info *pipe,
1296 size_t len, unsigned int flags)
1297{
1298 int ret;
1299 int page_nr = 0;
1300 int do_wakeup = 0;
1301 struct pipe_buffer *bufs;
1302 struct fuse_copy_state cs;
1303 struct fuse_conn *fc = fuse_get_conn(in);
1304 if (!fc)
1305 return -EPERM;
1306
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001307 bufs = kmalloc(pipe->buffers * sizeof(struct pipe_buffer), GFP_KERNEL);
Miklos Szeredic3021622010-05-25 15:06:07 +02001308 if (!bufs)
1309 return -ENOMEM;
1310
1311 fuse_copy_init(&cs, fc, 1, NULL, 0);
1312 cs.pipebufs = bufs;
1313 cs.pipe = pipe;
1314 ret = fuse_dev_do_read(fc, in, &cs, len);
1315 if (ret < 0)
1316 goto out;
1317
1318 ret = 0;
1319 pipe_lock(pipe);
1320
1321 if (!pipe->readers) {
1322 send_sig(SIGPIPE, current, 0);
1323 if (!ret)
1324 ret = -EPIPE;
1325 goto out_unlock;
1326 }
1327
1328 if (pipe->nrbufs + cs.nr_segs > pipe->buffers) {
1329 ret = -EIO;
1330 goto out_unlock;
1331 }
1332
1333 while (page_nr < cs.nr_segs) {
1334 int newbuf = (pipe->curbuf + pipe->nrbufs) & (pipe->buffers - 1);
1335 struct pipe_buffer *buf = pipe->bufs + newbuf;
1336
1337 buf->page = bufs[page_nr].page;
1338 buf->offset = bufs[page_nr].offset;
1339 buf->len = bufs[page_nr].len;
Miklos Szeredi28a625c2014-01-22 19:36:57 +01001340 /*
1341 * Need to be careful about this. Having buf->ops in module
1342 * code can Oops if the buffer persists after module unload.
1343 */
1344 buf->ops = &nosteal_pipe_buf_ops;
Miklos Szeredic3021622010-05-25 15:06:07 +02001345
1346 pipe->nrbufs++;
1347 page_nr++;
1348 ret += buf->len;
1349
Al Viro6447a3c2013-03-21 11:01:38 -04001350 if (pipe->files)
Miklos Szeredic3021622010-05-25 15:06:07 +02001351 do_wakeup = 1;
1352 }
1353
1354out_unlock:
1355 pipe_unlock(pipe);
1356
1357 if (do_wakeup) {
1358 smp_mb();
1359 if (waitqueue_active(&pipe->wait))
1360 wake_up_interruptible(&pipe->wait);
1361 kill_fasync(&pipe->fasync_readers, SIGIO, POLL_IN);
1362 }
1363
1364out:
1365 for (; page_nr < cs.nr_segs; page_nr++)
1366 page_cache_release(bufs[page_nr].page);
1367
1368 kfree(bufs);
1369 return ret;
1370}
1371
Tejun Heo95668a62008-11-26 12:03:55 +01001372static int fuse_notify_poll(struct fuse_conn *fc, unsigned int size,
1373 struct fuse_copy_state *cs)
1374{
1375 struct fuse_notify_poll_wakeup_out outarg;
Miklos Szeredif6d47a12009-01-26 15:00:59 +01001376 int err = -EINVAL;
Tejun Heo95668a62008-11-26 12:03:55 +01001377
1378 if (size != sizeof(outarg))
Miklos Szeredif6d47a12009-01-26 15:00:59 +01001379 goto err;
Tejun Heo95668a62008-11-26 12:03:55 +01001380
1381 err = fuse_copy_one(cs, &outarg, sizeof(outarg));
1382 if (err)
Miklos Szeredif6d47a12009-01-26 15:00:59 +01001383 goto err;
Tejun Heo95668a62008-11-26 12:03:55 +01001384
Miklos Szeredif6d47a12009-01-26 15:00:59 +01001385 fuse_copy_finish(cs);
Tejun Heo95668a62008-11-26 12:03:55 +01001386 return fuse_notify_poll_wakeup(fc, &outarg);
Miklos Szeredif6d47a12009-01-26 15:00:59 +01001387
1388err:
1389 fuse_copy_finish(cs);
1390 return err;
Tejun Heo95668a62008-11-26 12:03:55 +01001391}
1392
John Muir3b463ae2009-05-31 11:13:57 -04001393static int fuse_notify_inval_inode(struct fuse_conn *fc, unsigned int size,
1394 struct fuse_copy_state *cs)
1395{
1396 struct fuse_notify_inval_inode_out outarg;
1397 int err = -EINVAL;
1398
1399 if (size != sizeof(outarg))
1400 goto err;
1401
1402 err = fuse_copy_one(cs, &outarg, sizeof(outarg));
1403 if (err)
1404 goto err;
1405 fuse_copy_finish(cs);
1406
1407 down_read(&fc->killsb);
1408 err = -ENOENT;
Miklos Szeredib21dda42010-02-05 12:08:31 +01001409 if (fc->sb) {
1410 err = fuse_reverse_inval_inode(fc->sb, outarg.ino,
1411 outarg.off, outarg.len);
1412 }
John Muir3b463ae2009-05-31 11:13:57 -04001413 up_read(&fc->killsb);
1414 return err;
1415
1416err:
1417 fuse_copy_finish(cs);
1418 return err;
1419}
1420
1421static int fuse_notify_inval_entry(struct fuse_conn *fc, unsigned int size,
1422 struct fuse_copy_state *cs)
1423{
1424 struct fuse_notify_inval_entry_out outarg;
Fang Wenqib2d82ee2009-12-30 18:37:13 +08001425 int err = -ENOMEM;
1426 char *buf;
John Muir3b463ae2009-05-31 11:13:57 -04001427 struct qstr name;
1428
Fang Wenqib2d82ee2009-12-30 18:37:13 +08001429 buf = kzalloc(FUSE_NAME_MAX + 1, GFP_KERNEL);
1430 if (!buf)
1431 goto err;
1432
1433 err = -EINVAL;
John Muir3b463ae2009-05-31 11:13:57 -04001434 if (size < sizeof(outarg))
1435 goto err;
1436
1437 err = fuse_copy_one(cs, &outarg, sizeof(outarg));
1438 if (err)
1439 goto err;
1440
1441 err = -ENAMETOOLONG;
1442 if (outarg.namelen > FUSE_NAME_MAX)
1443 goto err;
1444
Miklos Szeredic2183d12011-08-24 10:20:17 +02001445 err = -EINVAL;
1446 if (size != sizeof(outarg) + outarg.namelen + 1)
1447 goto err;
1448
John Muir3b463ae2009-05-31 11:13:57 -04001449 name.name = buf;
1450 name.len = outarg.namelen;
1451 err = fuse_copy_one(cs, buf, outarg.namelen + 1);
1452 if (err)
1453 goto err;
1454 fuse_copy_finish(cs);
1455 buf[outarg.namelen] = 0;
1456 name.hash = full_name_hash(name.name, name.len);
1457
1458 down_read(&fc->killsb);
1459 err = -ENOENT;
Miklos Szeredib21dda42010-02-05 12:08:31 +01001460 if (fc->sb)
John Muir451d0f52011-12-06 21:50:06 +01001461 err = fuse_reverse_inval_entry(fc->sb, outarg.parent, 0, &name);
1462 up_read(&fc->killsb);
1463 kfree(buf);
1464 return err;
1465
1466err:
1467 kfree(buf);
1468 fuse_copy_finish(cs);
1469 return err;
1470}
1471
1472static int fuse_notify_delete(struct fuse_conn *fc, unsigned int size,
1473 struct fuse_copy_state *cs)
1474{
1475 struct fuse_notify_delete_out outarg;
1476 int err = -ENOMEM;
1477 char *buf;
1478 struct qstr name;
1479
1480 buf = kzalloc(FUSE_NAME_MAX + 1, GFP_KERNEL);
1481 if (!buf)
1482 goto err;
1483
1484 err = -EINVAL;
1485 if (size < sizeof(outarg))
1486 goto err;
1487
1488 err = fuse_copy_one(cs, &outarg, sizeof(outarg));
1489 if (err)
1490 goto err;
1491
1492 err = -ENAMETOOLONG;
1493 if (outarg.namelen > FUSE_NAME_MAX)
1494 goto err;
1495
1496 err = -EINVAL;
1497 if (size != sizeof(outarg) + outarg.namelen + 1)
1498 goto err;
1499
1500 name.name = buf;
1501 name.len = outarg.namelen;
1502 err = fuse_copy_one(cs, buf, outarg.namelen + 1);
1503 if (err)
1504 goto err;
1505 fuse_copy_finish(cs);
1506 buf[outarg.namelen] = 0;
1507 name.hash = full_name_hash(name.name, name.len);
1508
1509 down_read(&fc->killsb);
1510 err = -ENOENT;
1511 if (fc->sb)
1512 err = fuse_reverse_inval_entry(fc->sb, outarg.parent,
1513 outarg.child, &name);
John Muir3b463ae2009-05-31 11:13:57 -04001514 up_read(&fc->killsb);
Fang Wenqib2d82ee2009-12-30 18:37:13 +08001515 kfree(buf);
John Muir3b463ae2009-05-31 11:13:57 -04001516 return err;
1517
1518err:
Fang Wenqib2d82ee2009-12-30 18:37:13 +08001519 kfree(buf);
John Muir3b463ae2009-05-31 11:13:57 -04001520 fuse_copy_finish(cs);
1521 return err;
1522}
1523
Miklos Szeredia1d75f22010-07-12 14:41:40 +02001524static int fuse_notify_store(struct fuse_conn *fc, unsigned int size,
1525 struct fuse_copy_state *cs)
1526{
1527 struct fuse_notify_store_out outarg;
1528 struct inode *inode;
1529 struct address_space *mapping;
1530 u64 nodeid;
1531 int err;
1532 pgoff_t index;
1533 unsigned int offset;
1534 unsigned int num;
1535 loff_t file_size;
1536 loff_t end;
1537
1538 err = -EINVAL;
1539 if (size < sizeof(outarg))
1540 goto out_finish;
1541
1542 err = fuse_copy_one(cs, &outarg, sizeof(outarg));
1543 if (err)
1544 goto out_finish;
1545
1546 err = -EINVAL;
1547 if (size - sizeof(outarg) != outarg.size)
1548 goto out_finish;
1549
1550 nodeid = outarg.nodeid;
1551
1552 down_read(&fc->killsb);
1553
1554 err = -ENOENT;
1555 if (!fc->sb)
1556 goto out_up_killsb;
1557
1558 inode = ilookup5(fc->sb, nodeid, fuse_inode_eq, &nodeid);
1559 if (!inode)
1560 goto out_up_killsb;
1561
1562 mapping = inode->i_mapping;
1563 index = outarg.offset >> PAGE_CACHE_SHIFT;
1564 offset = outarg.offset & ~PAGE_CACHE_MASK;
1565 file_size = i_size_read(inode);
1566 end = outarg.offset + outarg.size;
1567 if (end > file_size) {
1568 file_size = end;
1569 fuse_write_update_size(inode, file_size);
1570 }
1571
1572 num = outarg.size;
1573 while (num) {
1574 struct page *page;
1575 unsigned int this_num;
1576
1577 err = -ENOMEM;
1578 page = find_or_create_page(mapping, index,
1579 mapping_gfp_mask(mapping));
1580 if (!page)
1581 goto out_iput;
1582
1583 this_num = min_t(unsigned, num, PAGE_CACHE_SIZE - offset);
1584 err = fuse_copy_page(cs, &page, offset, this_num, 0);
Miklos Szeredi063ec1e2014-01-22 19:36:58 +01001585 if (!err && offset == 0 &&
1586 (this_num == PAGE_CACHE_SIZE || file_size == end))
Miklos Szeredia1d75f22010-07-12 14:41:40 +02001587 SetPageUptodate(page);
1588 unlock_page(page);
1589 page_cache_release(page);
1590
1591 if (err)
1592 goto out_iput;
1593
1594 num -= this_num;
1595 offset = 0;
1596 index++;
1597 }
1598
1599 err = 0;
1600
1601out_iput:
1602 iput(inode);
1603out_up_killsb:
1604 up_read(&fc->killsb);
1605out_finish:
1606 fuse_copy_finish(cs);
1607 return err;
1608}
1609
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001610static void fuse_retrieve_end(struct fuse_conn *fc, struct fuse_req *req)
1611{
Miklos Szeredi0be85572010-10-27 15:34:46 -07001612 release_pages(req->pages, req->num_pages, 0);
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001613}
1614
1615static int fuse_retrieve(struct fuse_conn *fc, struct inode *inode,
1616 struct fuse_notify_retrieve_out *outarg)
1617{
1618 int err;
1619 struct address_space *mapping = inode->i_mapping;
1620 struct fuse_req *req;
1621 pgoff_t index;
1622 loff_t file_size;
1623 unsigned int num;
1624 unsigned int offset;
Geert Uytterhoeven01574432010-09-30 22:06:21 +02001625 size_t total_len = 0;
Maxim Patlasov4d53dc92012-10-26 19:48:42 +04001626 int num_pages;
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001627
1628 offset = outarg->offset & ~PAGE_CACHE_MASK;
Maxim Patlasov4d53dc92012-10-26 19:48:42 +04001629 file_size = i_size_read(inode);
1630
1631 num = outarg->size;
1632 if (outarg->offset > file_size)
1633 num = 0;
1634 else if (outarg->offset + num > file_size)
1635 num = file_size - outarg->offset;
1636
1637 num_pages = (num + offset + PAGE_SIZE - 1) >> PAGE_SHIFT;
1638 num_pages = min(num_pages, FUSE_MAX_PAGES_PER_REQ);
1639
1640 req = fuse_get_req(fc, num_pages);
1641 if (IS_ERR(req))
1642 return PTR_ERR(req);
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001643
1644 req->in.h.opcode = FUSE_NOTIFY_REPLY;
1645 req->in.h.nodeid = outarg->nodeid;
1646 req->in.numargs = 2;
1647 req->in.argpages = 1;
Maxim Patlasovb2430d72012-10-26 19:49:24 +04001648 req->page_descs[0].offset = offset;
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001649 req->end = fuse_retrieve_end;
1650
1651 index = outarg->offset >> PAGE_CACHE_SHIFT;
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001652
Maxim Patlasov4d53dc92012-10-26 19:48:42 +04001653 while (num && req->num_pages < num_pages) {
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001654 struct page *page;
1655 unsigned int this_num;
1656
1657 page = find_get_page(mapping, index);
1658 if (!page)
1659 break;
1660
1661 this_num = min_t(unsigned, num, PAGE_CACHE_SIZE - offset);
1662 req->pages[req->num_pages] = page;
Maxim Patlasov85f40ae2012-10-26 19:49:33 +04001663 req->page_descs[req->num_pages].length = this_num;
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001664 req->num_pages++;
1665
Miklos Szeredic9e67d42012-09-04 18:45:54 +02001666 offset = 0;
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001667 num -= this_num;
1668 total_len += this_num;
Miklos Szeredi48706d02011-12-13 10:36:59 +01001669 index++;
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001670 }
1671 req->misc.retrieve_in.offset = outarg->offset;
1672 req->misc.retrieve_in.size = total_len;
1673 req->in.args[0].size = sizeof(req->misc.retrieve_in);
1674 req->in.args[0].value = &req->misc.retrieve_in;
1675 req->in.args[1].size = total_len;
1676
1677 err = fuse_request_send_notify_reply(fc, req, outarg->notify_unique);
1678 if (err)
1679 fuse_retrieve_end(fc, req);
1680
1681 return err;
1682}
1683
1684static int fuse_notify_retrieve(struct fuse_conn *fc, unsigned int size,
1685 struct fuse_copy_state *cs)
1686{
1687 struct fuse_notify_retrieve_out outarg;
1688 struct inode *inode;
1689 int err;
1690
1691 err = -EINVAL;
1692 if (size != sizeof(outarg))
1693 goto copy_finish;
1694
1695 err = fuse_copy_one(cs, &outarg, sizeof(outarg));
1696 if (err)
1697 goto copy_finish;
1698
1699 fuse_copy_finish(cs);
1700
1701 down_read(&fc->killsb);
1702 err = -ENOENT;
1703 if (fc->sb) {
1704 u64 nodeid = outarg.nodeid;
1705
1706 inode = ilookup5(fc->sb, nodeid, fuse_inode_eq, &nodeid);
1707 if (inode) {
1708 err = fuse_retrieve(fc, inode, &outarg);
1709 iput(inode);
1710 }
1711 }
1712 up_read(&fc->killsb);
1713
1714 return err;
1715
1716copy_finish:
1717 fuse_copy_finish(cs);
1718 return err;
1719}
1720
Tejun Heo85993962008-11-26 12:03:55 +01001721static int fuse_notify(struct fuse_conn *fc, enum fuse_notify_code code,
1722 unsigned int size, struct fuse_copy_state *cs)
1723{
1724 switch (code) {
Tejun Heo95668a62008-11-26 12:03:55 +01001725 case FUSE_NOTIFY_POLL:
1726 return fuse_notify_poll(fc, size, cs);
1727
John Muir3b463ae2009-05-31 11:13:57 -04001728 case FUSE_NOTIFY_INVAL_INODE:
1729 return fuse_notify_inval_inode(fc, size, cs);
1730
1731 case FUSE_NOTIFY_INVAL_ENTRY:
1732 return fuse_notify_inval_entry(fc, size, cs);
1733
Miklos Szeredia1d75f22010-07-12 14:41:40 +02001734 case FUSE_NOTIFY_STORE:
1735 return fuse_notify_store(fc, size, cs);
1736
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001737 case FUSE_NOTIFY_RETRIEVE:
1738 return fuse_notify_retrieve(fc, size, cs);
1739
John Muir451d0f52011-12-06 21:50:06 +01001740 case FUSE_NOTIFY_DELETE:
1741 return fuse_notify_delete(fc, size, cs);
1742
Tejun Heo85993962008-11-26 12:03:55 +01001743 default:
Miklos Szeredif6d47a12009-01-26 15:00:59 +01001744 fuse_copy_finish(cs);
Tejun Heo85993962008-11-26 12:03:55 +01001745 return -EINVAL;
1746 }
1747}
1748
Miklos Szeredi334f4852005-09-09 13:10:27 -07001749/* Look up request on processing list by unique ID */
1750static struct fuse_req *request_find(struct fuse_conn *fc, u64 unique)
1751{
Dong Fang05726ac2013-07-30 22:50:01 -04001752 struct fuse_req *req;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001753
Dong Fang05726ac2013-07-30 22:50:01 -04001754 list_for_each_entry(req, &fc->processing, list) {
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001755 if (req->in.h.unique == unique || req->intr_unique == unique)
Miklos Szeredi334f4852005-09-09 13:10:27 -07001756 return req;
1757 }
1758 return NULL;
1759}
1760
1761static int copy_out_args(struct fuse_copy_state *cs, struct fuse_out *out,
1762 unsigned nbytes)
1763{
1764 unsigned reqsize = sizeof(struct fuse_out_header);
1765
1766 if (out->h.error)
1767 return nbytes != reqsize ? -EINVAL : 0;
1768
1769 reqsize += len_args(out->numargs, out->args);
1770
1771 if (reqsize < nbytes || (reqsize > nbytes && !out->argvar))
1772 return -EINVAL;
1773 else if (reqsize > nbytes) {
1774 struct fuse_arg *lastarg = &out->args[out->numargs-1];
1775 unsigned diffsize = reqsize - nbytes;
1776 if (diffsize > lastarg->size)
1777 return -EINVAL;
1778 lastarg->size -= diffsize;
1779 }
1780 return fuse_copy_args(cs, out->numargs, out->argpages, out->args,
1781 out->page_zeroing);
1782}
1783
1784/*
1785 * Write a single reply to a request. First the header is copied from
1786 * the write buffer. The request is then searched on the processing
1787 * list by the unique ID found in the header. If found, then remove
1788 * it from the list and copy the rest of the buffer to the request.
1789 * The request is finished by calling request_end()
1790 */
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001791static ssize_t fuse_dev_do_write(struct fuse_conn *fc,
1792 struct fuse_copy_state *cs, size_t nbytes)
Miklos Szeredi334f4852005-09-09 13:10:27 -07001793{
1794 int err;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001795 struct fuse_req *req;
1796 struct fuse_out_header oh;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001797
Miklos Szeredi334f4852005-09-09 13:10:27 -07001798 if (nbytes < sizeof(struct fuse_out_header))
1799 return -EINVAL;
1800
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001801 err = fuse_copy_one(cs, &oh, sizeof(oh));
Miklos Szeredi334f4852005-09-09 13:10:27 -07001802 if (err)
1803 goto err_finish;
Tejun Heo85993962008-11-26 12:03:55 +01001804
Miklos Szeredi334f4852005-09-09 13:10:27 -07001805 err = -EINVAL;
Tejun Heo85993962008-11-26 12:03:55 +01001806 if (oh.len != nbytes)
1807 goto err_finish;
1808
1809 /*
1810 * Zero oh.unique indicates unsolicited notification message
1811 * and error contains notification code.
1812 */
1813 if (!oh.unique) {
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001814 err = fuse_notify(fc, oh.error, nbytes - sizeof(oh), cs);
Tejun Heo85993962008-11-26 12:03:55 +01001815 return err ? err : nbytes;
1816 }
1817
1818 err = -EINVAL;
1819 if (oh.error <= -1000 || oh.error > 0)
Miklos Szeredi334f4852005-09-09 13:10:27 -07001820 goto err_finish;
1821
Miklos Szeredid7133112006-04-10 22:54:55 -07001822 spin_lock(&fc->lock);
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08001823 err = -ENOENT;
1824 if (!fc->connected)
1825 goto err_unlock;
1826
Miklos Szeredi334f4852005-09-09 13:10:27 -07001827 req = request_find(fc, oh.unique);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001828 if (!req)
1829 goto err_unlock;
1830
Miklos Szeredif9a28422006-06-25 05:48:53 -07001831 if (req->aborted) {
Miklos Szeredid7133112006-04-10 22:54:55 -07001832 spin_unlock(&fc->lock);
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001833 fuse_copy_finish(cs);
Miklos Szeredid7133112006-04-10 22:54:55 -07001834 spin_lock(&fc->lock);
Miklos Szeredi222f1d692006-01-16 22:14:25 -08001835 request_end(fc, req);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001836 return -ENOENT;
1837 }
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001838 /* Is it an interrupt reply? */
1839 if (req->intr_unique == oh.unique) {
1840 err = -EINVAL;
1841 if (nbytes != sizeof(struct fuse_out_header))
1842 goto err_unlock;
1843
1844 if (oh.error == -ENOSYS)
1845 fc->no_interrupt = 1;
1846 else if (oh.error == -EAGAIN)
1847 queue_interrupt(fc, req);
1848
1849 spin_unlock(&fc->lock);
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001850 fuse_copy_finish(cs);
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001851 return nbytes;
1852 }
1853
1854 req->state = FUSE_REQ_WRITING;
Miklos Szeredid77a1d52006-01-16 22:14:31 -08001855 list_move(&req->list, &fc->io);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001856 req->out.h = oh;
1857 req->locked = 1;
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001858 cs->req = req;
Miklos Szeredice534fb2010-05-25 15:06:07 +02001859 if (!req->out.page_replace)
1860 cs->move_pages = 0;
Miklos Szeredid7133112006-04-10 22:54:55 -07001861 spin_unlock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001862
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001863 err = copy_out_args(cs, &req->out, nbytes);
1864 fuse_copy_finish(cs);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001865
Miklos Szeredid7133112006-04-10 22:54:55 -07001866 spin_lock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001867 req->locked = 0;
1868 if (!err) {
Miklos Szeredif9a28422006-06-25 05:48:53 -07001869 if (req->aborted)
Miklos Szeredi334f4852005-09-09 13:10:27 -07001870 err = -ENOENT;
Miklos Szeredif9a28422006-06-25 05:48:53 -07001871 } else if (!req->aborted)
Miklos Szeredi334f4852005-09-09 13:10:27 -07001872 req->out.h.error = -EIO;
1873 request_end(fc, req);
1874
1875 return err ? err : nbytes;
1876
1877 err_unlock:
Miklos Szeredid7133112006-04-10 22:54:55 -07001878 spin_unlock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001879 err_finish:
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001880 fuse_copy_finish(cs);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001881 return err;
1882}
1883
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001884static ssize_t fuse_dev_write(struct kiocb *iocb, const struct iovec *iov,
1885 unsigned long nr_segs, loff_t pos)
1886{
1887 struct fuse_copy_state cs;
1888 struct fuse_conn *fc = fuse_get_conn(iocb->ki_filp);
1889 if (!fc)
1890 return -EPERM;
1891
Miklos Szeredic3021622010-05-25 15:06:07 +02001892 fuse_copy_init(&cs, fc, 0, iov, nr_segs);
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001893
1894 return fuse_dev_do_write(fc, &cs, iov_length(iov, nr_segs));
1895}
1896
1897static ssize_t fuse_dev_splice_write(struct pipe_inode_info *pipe,
1898 struct file *out, loff_t *ppos,
1899 size_t len, unsigned int flags)
1900{
1901 unsigned nbuf;
1902 unsigned idx;
1903 struct pipe_buffer *bufs;
1904 struct fuse_copy_state cs;
1905 struct fuse_conn *fc;
1906 size_t rem;
1907 ssize_t ret;
1908
1909 fc = fuse_get_conn(out);
1910 if (!fc)
1911 return -EPERM;
1912
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001913 bufs = kmalloc(pipe->buffers * sizeof(struct pipe_buffer), GFP_KERNEL);
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001914 if (!bufs)
1915 return -ENOMEM;
1916
1917 pipe_lock(pipe);
1918 nbuf = 0;
1919 rem = 0;
1920 for (idx = 0; idx < pipe->nrbufs && rem < len; idx++)
1921 rem += pipe->bufs[(pipe->curbuf + idx) & (pipe->buffers - 1)].len;
1922
1923 ret = -EINVAL;
1924 if (rem < len) {
1925 pipe_unlock(pipe);
1926 goto out;
1927 }
1928
1929 rem = len;
1930 while (rem) {
1931 struct pipe_buffer *ibuf;
1932 struct pipe_buffer *obuf;
1933
1934 BUG_ON(nbuf >= pipe->buffers);
1935 BUG_ON(!pipe->nrbufs);
1936 ibuf = &pipe->bufs[pipe->curbuf];
1937 obuf = &bufs[nbuf];
1938
1939 if (rem >= ibuf->len) {
1940 *obuf = *ibuf;
1941 ibuf->ops = NULL;
1942 pipe->curbuf = (pipe->curbuf + 1) & (pipe->buffers - 1);
1943 pipe->nrbufs--;
1944 } else {
1945 ibuf->ops->get(pipe, ibuf);
1946 *obuf = *ibuf;
1947 obuf->flags &= ~PIPE_BUF_FLAG_GIFT;
1948 obuf->len = rem;
1949 ibuf->offset += obuf->len;
1950 ibuf->len -= obuf->len;
1951 }
1952 nbuf++;
1953 rem -= obuf->len;
1954 }
1955 pipe_unlock(pipe);
1956
Miklos Szeredic3021622010-05-25 15:06:07 +02001957 fuse_copy_init(&cs, fc, 0, NULL, nbuf);
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001958 cs.pipebufs = bufs;
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001959 cs.pipe = pipe;
1960
Miklos Szeredice534fb2010-05-25 15:06:07 +02001961 if (flags & SPLICE_F_MOVE)
1962 cs.move_pages = 1;
1963
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001964 ret = fuse_dev_do_write(fc, &cs, len);
1965
1966 for (idx = 0; idx < nbuf; idx++) {
1967 struct pipe_buffer *buf = &bufs[idx];
1968 buf->ops->release(pipe, buf);
1969 }
1970out:
1971 kfree(bufs);
1972 return ret;
1973}
1974
Miklos Szeredi334f4852005-09-09 13:10:27 -07001975static unsigned fuse_dev_poll(struct file *file, poll_table *wait)
1976{
Miklos Szeredi334f4852005-09-09 13:10:27 -07001977 unsigned mask = POLLOUT | POLLWRNORM;
Miklos Szeredi7025d9a2006-04-10 22:54:50 -07001978 struct fuse_conn *fc = fuse_get_conn(file);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001979 if (!fc)
Miklos Szeredi7025d9a2006-04-10 22:54:50 -07001980 return POLLERR;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001981
1982 poll_wait(file, &fc->waitq, wait);
1983
Miklos Szeredid7133112006-04-10 22:54:55 -07001984 spin_lock(&fc->lock);
Miklos Szeredi7025d9a2006-04-10 22:54:50 -07001985 if (!fc->connected)
1986 mask = POLLERR;
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001987 else if (request_pending(fc))
Miklos Szeredi7025d9a2006-04-10 22:54:50 -07001988 mask |= POLLIN | POLLRDNORM;
Miklos Szeredid7133112006-04-10 22:54:55 -07001989 spin_unlock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001990
1991 return mask;
1992}
1993
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08001994/*
1995 * Abort all requests on the given list (pending or processing)
1996 *
Miklos Szeredid7133112006-04-10 22:54:55 -07001997 * This function releases and reacquires fc->lock
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08001998 */
Miklos Szeredi334f4852005-09-09 13:10:27 -07001999static void end_requests(struct fuse_conn *fc, struct list_head *head)
Miklos Szeredib9ca67b2010-09-07 13:42:41 +02002000__releases(fc->lock)
2001__acquires(fc->lock)
Miklos Szeredi334f4852005-09-09 13:10:27 -07002002{
2003 while (!list_empty(head)) {
2004 struct fuse_req *req;
2005 req = list_entry(head->next, struct fuse_req, list);
Miklos Szeredi334f4852005-09-09 13:10:27 -07002006 req->out.h.error = -ECONNABORTED;
2007 request_end(fc, req);
Miklos Szeredid7133112006-04-10 22:54:55 -07002008 spin_lock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -07002009 }
2010}
2011
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002012/*
2013 * Abort requests under I/O
2014 *
Miklos Szeredif9a28422006-06-25 05:48:53 -07002015 * The requests are set to aborted and finished, and the request
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002016 * waiter is woken up. This will make request_wait_answer() wait
2017 * until the request is unlocked and then return.
Miklos Szeredi64c6d8e2006-01-16 22:14:42 -08002018 *
2019 * If the request is asynchronous, then the end function needs to be
2020 * called after waiting for the request to be unlocked (if it was
2021 * locked).
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002022 */
2023static void end_io_requests(struct fuse_conn *fc)
Miklos Szeredib9ca67b2010-09-07 13:42:41 +02002024__releases(fc->lock)
2025__acquires(fc->lock)
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002026{
2027 while (!list_empty(&fc->io)) {
Miklos Szeredi64c6d8e2006-01-16 22:14:42 -08002028 struct fuse_req *req =
2029 list_entry(fc->io.next, struct fuse_req, list);
2030 void (*end) (struct fuse_conn *, struct fuse_req *) = req->end;
2031
Miklos Szeredif9a28422006-06-25 05:48:53 -07002032 req->aborted = 1;
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002033 req->out.h.error = -ECONNABORTED;
2034 req->state = FUSE_REQ_FINISHED;
2035 list_del_init(&req->list);
2036 wake_up(&req->waitq);
Miklos Szeredi64c6d8e2006-01-16 22:14:42 -08002037 if (end) {
2038 req->end = NULL;
Miklos Szeredi64c6d8e2006-01-16 22:14:42 -08002039 __fuse_get_request(req);
Miklos Szeredid7133112006-04-10 22:54:55 -07002040 spin_unlock(&fc->lock);
Miklos Szeredi64c6d8e2006-01-16 22:14:42 -08002041 wait_event(req->waitq, !req->locked);
2042 end(fc, req);
Tejun Heoe9bb09d2008-11-26 12:03:54 +01002043 fuse_put_request(fc, req);
Miklos Szeredid7133112006-04-10 22:54:55 -07002044 spin_lock(&fc->lock);
Miklos Szeredi64c6d8e2006-01-16 22:14:42 -08002045 }
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002046 }
2047}
2048
Miklos Szeredi595afaf2010-09-07 13:42:41 +02002049static void end_queued_requests(struct fuse_conn *fc)
Miklos Szeredib9ca67b2010-09-07 13:42:41 +02002050__releases(fc->lock)
2051__acquires(fc->lock)
Miklos Szeredi595afaf2010-09-07 13:42:41 +02002052{
2053 fc->max_background = UINT_MAX;
2054 flush_bg_queue(fc);
2055 end_requests(fc, &fc->pending);
2056 end_requests(fc, &fc->processing);
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01002057 while (forget_pending(fc))
Miklos Szeredi02c048b2010-12-07 20:16:56 +01002058 kfree(dequeue_forget(fc, 1, NULL));
Miklos Szeredi595afaf2010-09-07 13:42:41 +02002059}
2060
Bryan Green357ccf22011-03-01 16:43:52 -08002061static void end_polls(struct fuse_conn *fc)
2062{
2063 struct rb_node *p;
2064
2065 p = rb_first(&fc->polled_files);
2066
2067 while (p) {
2068 struct fuse_file *ff;
2069 ff = rb_entry(p, struct fuse_file, polled_node);
2070 wake_up_interruptible_all(&ff->poll_wait);
2071
2072 p = rb_next(p);
2073 }
2074}
2075
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002076/*
2077 * Abort all requests.
2078 *
2079 * Emergency exit in case of a malicious or accidental deadlock, or
2080 * just a hung filesystem.
2081 *
2082 * The same effect is usually achievable through killing the
2083 * filesystem daemon and all users of the filesystem. The exception
2084 * is the combination of an asynchronous request and the tricky
2085 * deadlock (see Documentation/filesystems/fuse.txt).
2086 *
2087 * During the aborting, progression of requests from the pending and
2088 * processing lists onto the io list, and progression of new requests
2089 * onto the pending list is prevented by req->connected being false.
2090 *
2091 * Progression of requests under I/O to the processing list is
Miklos Szeredif9a28422006-06-25 05:48:53 -07002092 * prevented by the req->aborted flag being true for these requests.
2093 * For this reason requests on the io list must be aborted first.
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002094 */
2095void fuse_abort_conn(struct fuse_conn *fc)
2096{
Miklos Szeredid7133112006-04-10 22:54:55 -07002097 spin_lock(&fc->lock);
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002098 if (fc->connected) {
2099 fc->connected = 0;
Miklos Szeredi51eb01e2006-06-25 05:48:50 -07002100 fc->blocked = 0;
Maxim Patlasov796523fb2013-03-21 18:02:15 +04002101 fc->initialized = 1;
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002102 end_io_requests(fc);
Miklos Szeredi595afaf2010-09-07 13:42:41 +02002103 end_queued_requests(fc);
Bryan Green357ccf22011-03-01 16:43:52 -08002104 end_polls(fc);
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002105 wake_up_all(&fc->waitq);
Miklos Szeredi51eb01e2006-06-25 05:48:50 -07002106 wake_up_all(&fc->blocked_waitq);
Jeff Dike385a17b2006-04-10 22:54:52 -07002107 kill_fasync(&fc->fasync, SIGIO, POLL_IN);
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002108 }
Miklos Szeredid7133112006-04-10 22:54:55 -07002109 spin_unlock(&fc->lock);
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002110}
Tejun Heo08cbf542009-04-14 10:54:53 +09002111EXPORT_SYMBOL_GPL(fuse_abort_conn);
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002112
Tejun Heo08cbf542009-04-14 10:54:53 +09002113int fuse_dev_release(struct inode *inode, struct file *file)
Miklos Szeredi334f4852005-09-09 13:10:27 -07002114{
Miklos Szeredi0720b312006-04-10 22:54:55 -07002115 struct fuse_conn *fc = fuse_get_conn(file);
Miklos Szeredi334f4852005-09-09 13:10:27 -07002116 if (fc) {
Miklos Szeredid7133112006-04-10 22:54:55 -07002117 spin_lock(&fc->lock);
Miklos Szeredi1e9a4ed2005-09-09 13:10:31 -07002118 fc->connected = 0;
Miklos Szeredi595afaf2010-09-07 13:42:41 +02002119 fc->blocked = 0;
Maxim Patlasov0aada882013-03-21 18:02:28 +04002120 fc->initialized = 1;
Miklos Szeredi595afaf2010-09-07 13:42:41 +02002121 end_queued_requests(fc);
Bryan Green357ccf22011-03-01 16:43:52 -08002122 end_polls(fc);
Miklos Szeredi595afaf2010-09-07 13:42:41 +02002123 wake_up_all(&fc->blocked_waitq);
Miklos Szeredid7133112006-04-10 22:54:55 -07002124 spin_unlock(&fc->lock);
Miklos Szeredibafa9652006-06-25 05:48:51 -07002125 fuse_conn_put(fc);
Jeff Dike385a17b2006-04-10 22:54:52 -07002126 }
Miklos Szeredif543f252006-01-16 22:14:35 -08002127
Miklos Szeredi334f4852005-09-09 13:10:27 -07002128 return 0;
2129}
Tejun Heo08cbf542009-04-14 10:54:53 +09002130EXPORT_SYMBOL_GPL(fuse_dev_release);
Miklos Szeredi334f4852005-09-09 13:10:27 -07002131
Jeff Dike385a17b2006-04-10 22:54:52 -07002132static int fuse_dev_fasync(int fd, struct file *file, int on)
2133{
2134 struct fuse_conn *fc = fuse_get_conn(file);
2135 if (!fc)
Miklos Szeredia87046d2006-04-10 22:54:56 -07002136 return -EPERM;
Jeff Dike385a17b2006-04-10 22:54:52 -07002137
2138 /* No locking - fasync_helper does its own locking */
2139 return fasync_helper(fd, file, on, &fc->fasync);
2140}
2141
Arjan van de Ven4b6f5d22006-03-28 01:56:42 -08002142const struct file_operations fuse_dev_operations = {
Miklos Szeredi334f4852005-09-09 13:10:27 -07002143 .owner = THIS_MODULE,
2144 .llseek = no_llseek,
Badari Pulavartyee0b3e62006-09-30 23:28:47 -07002145 .read = do_sync_read,
2146 .aio_read = fuse_dev_read,
Miklos Szeredic3021622010-05-25 15:06:07 +02002147 .splice_read = fuse_dev_splice_read,
Badari Pulavartyee0b3e62006-09-30 23:28:47 -07002148 .write = do_sync_write,
2149 .aio_write = fuse_dev_write,
Miklos Szeredidd3bb142010-05-25 15:06:06 +02002150 .splice_write = fuse_dev_splice_write,
Miklos Szeredi334f4852005-09-09 13:10:27 -07002151 .poll = fuse_dev_poll,
2152 .release = fuse_dev_release,
Jeff Dike385a17b2006-04-10 22:54:52 -07002153 .fasync = fuse_dev_fasync,
Miklos Szeredi334f4852005-09-09 13:10:27 -07002154};
Tejun Heo08cbf542009-04-14 10:54:53 +09002155EXPORT_SYMBOL_GPL(fuse_dev_operations);
Miklos Szeredi334f4852005-09-09 13:10:27 -07002156
2157static struct miscdevice fuse_miscdevice = {
2158 .minor = FUSE_MINOR,
2159 .name = "fuse",
2160 .fops = &fuse_dev_operations,
2161};
2162
2163int __init fuse_dev_init(void)
2164{
2165 int err = -ENOMEM;
2166 fuse_req_cachep = kmem_cache_create("fuse_request",
2167 sizeof(struct fuse_req),
Paul Mundt20c2df82007-07-20 10:11:58 +09002168 0, 0, NULL);
Miklos Szeredi334f4852005-09-09 13:10:27 -07002169 if (!fuse_req_cachep)
2170 goto out;
2171
2172 err = misc_register(&fuse_miscdevice);
2173 if (err)
2174 goto out_cache_clean;
2175
2176 return 0;
2177
2178 out_cache_clean:
2179 kmem_cache_destroy(fuse_req_cachep);
2180 out:
2181 return err;
2182}
2183
2184void fuse_dev_cleanup(void)
2185{
2186 misc_deregister(&fuse_miscdevice);
2187 kmem_cache_destroy(fuse_req_cachep);
2188}