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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>
Miklos Szeredi334f4852005-09-09 13:10:27 -070022
23MODULE_ALIAS_MISCDEV(FUSE_MINOR);
Kay Sievers578454f2010-05-20 18:07:20 +020024MODULE_ALIAS("devname:fuse");
Miklos Szeredi334f4852005-09-09 13:10:27 -070025
Christoph Lametere18b8902006-12-06 20:33:20 -080026static struct kmem_cache *fuse_req_cachep;
Miklos Szeredi334f4852005-09-09 13:10:27 -070027
Miklos Szeredicc080e92015-07-01 16:26:08 +020028static struct fuse_dev *fuse_get_dev(struct file *file)
Miklos Szeredi334f4852005-09-09 13:10:27 -070029{
Miklos Szeredi0720b312006-04-10 22:54:55 -070030 /*
31 * Lockless access is OK, because file->private data is set
32 * once during mount and is valid until the file is released.
33 */
Miklos Szeredicc080e92015-07-01 16:26:08 +020034 return ACCESS_ONCE(file->private_data);
Miklos Szeredi334f4852005-09-09 13:10:27 -070035}
36
Maxim Patlasov4250c062012-10-26 19:48:07 +040037static void fuse_request_init(struct fuse_req *req, struct page **pages,
Maxim Patlasovb2430d72012-10-26 19:49:24 +040038 struct fuse_page_desc *page_descs,
Maxim Patlasov4250c062012-10-26 19:48:07 +040039 unsigned npages)
Miklos Szeredi334f4852005-09-09 13:10:27 -070040{
41 memset(req, 0, sizeof(*req));
Maxim Patlasov4250c062012-10-26 19:48:07 +040042 memset(pages, 0, sizeof(*pages) * npages);
Maxim Patlasovb2430d72012-10-26 19:49:24 +040043 memset(page_descs, 0, sizeof(*page_descs) * npages);
Miklos Szeredi334f4852005-09-09 13:10:27 -070044 INIT_LIST_HEAD(&req->list);
Miklos Szeredia4d27e72006-06-25 05:48:54 -070045 INIT_LIST_HEAD(&req->intr_entry);
Miklos Szeredi334f4852005-09-09 13:10:27 -070046 init_waitqueue_head(&req->waitq);
47 atomic_set(&req->count, 1);
Maxim Patlasov4250c062012-10-26 19:48:07 +040048 req->pages = pages;
Maxim Patlasovb2430d72012-10-26 19:49:24 +040049 req->page_descs = page_descs;
Maxim Patlasov4250c062012-10-26 19:48:07 +040050 req->max_pages = npages;
Miklos Szeredi33e14b42015-07-01 16:26:01 +020051 __set_bit(FR_PENDING, &req->flags);
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
Maxim Patlasov36cf66e2012-12-14 19:20:51 +0400102void __fuse_get_request(struct fuse_req *req)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700103{
104 atomic_inc(&req->count);
105}
106
107/* Must be called with > 1 refcount */
108static void __fuse_put_request(struct fuse_req *req)
109{
110 BUG_ON(atomic_read(&req->count) < 2);
111 atomic_dec(&req->count);
112}
113
Miklos Szeredi33649c92006-06-25 05:48:52 -0700114static void fuse_req_init_context(struct fuse_req *req)
115{
Eric W. Biederman499dcf22012-02-07 16:26:03 -0800116 req->in.h.uid = from_kuid_munged(&init_user_ns, current_fsuid());
117 req->in.h.gid = from_kgid_munged(&init_user_ns, current_fsgid());
Miklos Szeredi33649c92006-06-25 05:48:52 -0700118 req->in.h.pid = current->pid;
119}
120
Miklos Szeredi9759bd512015-01-06 10:45:35 +0100121void fuse_set_initialized(struct fuse_conn *fc)
122{
123 /* Make sure stores before this are seen on another CPU */
124 smp_wmb();
125 fc->initialized = 1;
126}
127
Maxim Patlasov0aada882013-03-21 18:02:28 +0400128static bool fuse_block_alloc(struct fuse_conn *fc, bool for_background)
129{
130 return !fc->initialized || (for_background && fc->blocked);
131}
132
Maxim Patlasov8b41e672013-03-21 18:02:04 +0400133static struct fuse_req *__fuse_get_req(struct fuse_conn *fc, unsigned npages,
134 bool for_background)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700135{
Miklos Szeredi08a53cd2006-04-10 22:54:59 -0700136 struct fuse_req *req;
Miklos Szeredi08a53cd2006-04-10 22:54:59 -0700137 int err;
Miklos Szeredi9bc5ddd2006-04-11 21:16:09 +0200138 atomic_inc(&fc->num_waiting);
Maxim Patlasov0aada882013-03-21 18:02:28 +0400139
140 if (fuse_block_alloc(fc, for_background)) {
Maxim Patlasov0aada882013-03-21 18:02:28 +0400141 err = -EINTR;
Al Viro7d3a07f2016-07-19 03:08:27 -0400142 if (wait_event_killable_exclusive(fc->blocked_waitq,
143 !fuse_block_alloc(fc, for_background)))
Maxim Patlasov0aada882013-03-21 18:02:28 +0400144 goto out;
145 }
Miklos Szeredi9759bd512015-01-06 10:45:35 +0100146 /* Matches smp_wmb() in fuse_set_initialized() */
147 smp_rmb();
Miklos Szeredi08a53cd2006-04-10 22:54:59 -0700148
Miklos Szeredi51eb01e2006-06-25 05:48:50 -0700149 err = -ENOTCONN;
150 if (!fc->connected)
151 goto out;
152
Miklos Szeredide155222015-07-01 16:25:57 +0200153 err = -ECONNREFUSED;
154 if (fc->conn_error)
155 goto out;
156
Maxim Patlasovb111c8c2012-10-26 19:48:30 +0400157 req = fuse_request_alloc(npages);
Miklos Szeredi9bc5ddd2006-04-11 21:16:09 +0200158 err = -ENOMEM;
Maxim Patlasov722d2be2013-03-21 18:02:36 +0400159 if (!req) {
160 if (for_background)
161 wake_up(&fc->blocked_waitq);
Miklos Szeredi9bc5ddd2006-04-11 21:16:09 +0200162 goto out;
Maxim Patlasov722d2be2013-03-21 18:02:36 +0400163 }
Miklos Szeredi334f4852005-09-09 13:10:27 -0700164
Miklos Szeredi33649c92006-06-25 05:48:52 -0700165 fuse_req_init_context(req);
Miklos Szeredi825d6d32015-07-01 16:25:58 +0200166 __set_bit(FR_WAITING, &req->flags);
167 if (for_background)
168 __set_bit(FR_BACKGROUND, &req->flags);
169
Miklos Szeredi334f4852005-09-09 13:10:27 -0700170 return req;
Miklos Szeredi9bc5ddd2006-04-11 21:16:09 +0200171
172 out:
173 atomic_dec(&fc->num_waiting);
174 return ERR_PTR(err);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700175}
Maxim Patlasov8b41e672013-03-21 18:02:04 +0400176
177struct fuse_req *fuse_get_req(struct fuse_conn *fc, unsigned npages)
178{
179 return __fuse_get_req(fc, npages, false);
180}
Tejun Heo08cbf542009-04-14 10:54:53 +0900181EXPORT_SYMBOL_GPL(fuse_get_req);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700182
Maxim Patlasov8b41e672013-03-21 18:02:04 +0400183struct fuse_req *fuse_get_req_for_background(struct fuse_conn *fc,
184 unsigned npages)
185{
186 return __fuse_get_req(fc, npages, true);
187}
188EXPORT_SYMBOL_GPL(fuse_get_req_for_background);
189
Miklos Szeredi33649c92006-06-25 05:48:52 -0700190/*
191 * Return request in fuse_file->reserved_req. However that may
192 * currently be in use. If that is the case, wait for it to become
193 * available.
194 */
195static struct fuse_req *get_reserved_req(struct fuse_conn *fc,
196 struct file *file)
197{
198 struct fuse_req *req = NULL;
199 struct fuse_file *ff = file->private_data;
200
201 do {
Miklos Szeredide5e3de2007-10-16 23:31:00 -0700202 wait_event(fc->reserved_req_waitq, ff->reserved_req);
Miklos Szeredi33649c92006-06-25 05:48:52 -0700203 spin_lock(&fc->lock);
204 if (ff->reserved_req) {
205 req = ff->reserved_req;
206 ff->reserved_req = NULL;
Al Virocb0942b2012-08-27 14:48:26 -0400207 req->stolen_file = get_file(file);
Miklos Szeredi33649c92006-06-25 05:48:52 -0700208 }
209 spin_unlock(&fc->lock);
210 } while (!req);
211
212 return req;
213}
214
215/*
216 * Put stolen request back into fuse_file->reserved_req
217 */
218static void put_reserved_req(struct fuse_conn *fc, struct fuse_req *req)
219{
220 struct file *file = req->stolen_file;
221 struct fuse_file *ff = file->private_data;
222
223 spin_lock(&fc->lock);
Maxim Patlasovb2430d72012-10-26 19:49:24 +0400224 fuse_request_init(req, req->pages, req->page_descs, req->max_pages);
Miklos Szeredi33649c92006-06-25 05:48:52 -0700225 BUG_ON(ff->reserved_req);
226 ff->reserved_req = req;
Miklos Szeredide5e3de2007-10-16 23:31:00 -0700227 wake_up_all(&fc->reserved_req_waitq);
Miklos Szeredi33649c92006-06-25 05:48:52 -0700228 spin_unlock(&fc->lock);
229 fput(file);
230}
231
232/*
233 * Gets a requests for a file operation, always succeeds
234 *
235 * This is used for sending the FLUSH request, which must get to
236 * userspace, due to POSIX locks which may need to be unlocked.
237 *
238 * If allocation fails due to OOM, use the reserved request in
239 * fuse_file.
240 *
241 * This is very unlikely to deadlock accidentally, since the
242 * filesystem should not have it's own file open. If deadlock is
243 * intentional, it can still be broken by "aborting" the filesystem.
244 */
Maxim Patlasovb111c8c2012-10-26 19:48:30 +0400245struct fuse_req *fuse_get_req_nofail_nopages(struct fuse_conn *fc,
246 struct file *file)
Miklos Szeredi33649c92006-06-25 05:48:52 -0700247{
248 struct fuse_req *req;
249
250 atomic_inc(&fc->num_waiting);
Maxim Patlasov0aada882013-03-21 18:02:28 +0400251 wait_event(fc->blocked_waitq, fc->initialized);
Miklos Szeredi9759bd512015-01-06 10:45:35 +0100252 /* Matches smp_wmb() in fuse_set_initialized() */
253 smp_rmb();
Maxim Patlasovb111c8c2012-10-26 19:48:30 +0400254 req = fuse_request_alloc(0);
Miklos Szeredi33649c92006-06-25 05:48:52 -0700255 if (!req)
256 req = get_reserved_req(fc, file);
257
258 fuse_req_init_context(req);
Miklos Szeredi825d6d32015-07-01 16:25:58 +0200259 __set_bit(FR_WAITING, &req->flags);
260 __clear_bit(FR_BACKGROUND, &req->flags);
Miklos Szeredi33649c92006-06-25 05:48:52 -0700261 return req;
262}
263
Miklos Szeredi334f4852005-09-09 13:10:27 -0700264void fuse_put_request(struct fuse_conn *fc, struct fuse_req *req)
265{
Miklos Szeredi7128ec22006-02-04 23:27:40 -0800266 if (atomic_dec_and_test(&req->count)) {
Miklos Szeredi825d6d32015-07-01 16:25:58 +0200267 if (test_bit(FR_BACKGROUND, &req->flags)) {
Maxim Patlasov722d2be2013-03-21 18:02:36 +0400268 /*
269 * We get here in the unlikely case that a background
270 * request was allocated but not sent
271 */
272 spin_lock(&fc->lock);
273 if (!fc->blocked)
274 wake_up(&fc->blocked_waitq);
275 spin_unlock(&fc->lock);
276 }
277
Miklos Szeredi825d6d32015-07-01 16:25:58 +0200278 if (test_bit(FR_WAITING, &req->flags)) {
279 __clear_bit(FR_WAITING, &req->flags);
Miklos Szeredi9bc5ddd2006-04-11 21:16:09 +0200280 atomic_dec(&fc->num_waiting);
Miklos Szeredi73e0e732015-07-01 16:25:56 +0200281 }
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
Miklos Szeredif88996a2015-07-01 16:26:01 +0200302static u64 fuse_get_unique(struct fuse_iqueue *fiq)
Miklos Szeredid12def12008-02-06 01:38:39 -0800303{
Miklos Szeredif88996a2015-07-01 16:26:01 +0200304 return ++fiq->reqctr;
Miklos Szeredid12def12008-02-06 01:38:39 -0800305}
306
Miklos Szeredif88996a2015-07-01 16:26:01 +0200307static void queue_request(struct fuse_iqueue *fiq, struct fuse_req *req)
Miklos Szeredid12def12008-02-06 01:38:39 -0800308{
Miklos Szeredid12def12008-02-06 01:38:39 -0800309 req->in.h.len = sizeof(struct fuse_in_header) +
310 len_args(req->in.numargs, (struct fuse_arg *) req->in.args);
Miklos Szeredif88996a2015-07-01 16:26:01 +0200311 list_add_tail(&req->list, &fiq->pending);
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200312 wake_up_locked(&fiq->waitq);
Miklos Szeredif88996a2015-07-01 16:26:01 +0200313 kill_fasync(&fiq->fasync, SIGIO, POLL_IN);
Miklos Szeredid12def12008-02-06 01:38:39 -0800314}
315
Miklos Szeredi07e77dc2010-12-07 20:16:56 +0100316void fuse_queue_forget(struct fuse_conn *fc, struct fuse_forget_link *forget,
317 u64 nodeid, u64 nlookup)
318{
Miklos Szeredif88996a2015-07-01 16:26:01 +0200319 struct fuse_iqueue *fiq = &fc->iq;
320
Miklos Szeredi02c048b2010-12-07 20:16:56 +0100321 forget->forget_one.nodeid = nodeid;
322 forget->forget_one.nlookup = nlookup;
Miklos Szeredi07e77dc2010-12-07 20:16:56 +0100323
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200324 spin_lock(&fiq->waitq.lock);
Miklos Szeredie16714d2015-07-01 16:26:01 +0200325 if (fiq->connected) {
Miklos Szeredif88996a2015-07-01 16:26:01 +0200326 fiq->forget_list_tail->next = forget;
327 fiq->forget_list_tail = forget;
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200328 wake_up_locked(&fiq->waitq);
Miklos Szeredif88996a2015-07-01 16:26:01 +0200329 kill_fasync(&fiq->fasync, SIGIO, POLL_IN);
Miklos Szeredi5dfcc872011-09-12 09:38:03 +0200330 } else {
331 kfree(forget);
332 }
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200333 spin_unlock(&fiq->waitq.lock);
Miklos Szeredi07e77dc2010-12-07 20:16:56 +0100334}
335
Miklos Szeredid12def12008-02-06 01:38:39 -0800336static void flush_bg_queue(struct fuse_conn *fc)
337{
Csaba Henk7a6d3c82009-07-01 17:28:41 -0700338 while (fc->active_background < fc->max_background &&
Miklos Szeredid12def12008-02-06 01:38:39 -0800339 !list_empty(&fc->bg_queue)) {
340 struct fuse_req *req;
Miklos Szeredif88996a2015-07-01 16:26:01 +0200341 struct fuse_iqueue *fiq = &fc->iq;
Miklos Szeredid12def12008-02-06 01:38:39 -0800342
343 req = list_entry(fc->bg_queue.next, struct fuse_req, list);
344 list_del(&req->list);
345 fc->active_background++;
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200346 spin_lock(&fiq->waitq.lock);
Miklos Szeredif88996a2015-07-01 16:26:01 +0200347 req->in.h.unique = fuse_get_unique(fiq);
348 queue_request(fiq, req);
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200349 spin_unlock(&fiq->waitq.lock);
Miklos Szeredid12def12008-02-06 01:38:39 -0800350 }
351}
352
Miklos Szeredi6dbbcb12006-04-26 10:49:06 +0200353/*
Miklos Szeredi334f4852005-09-09 13:10:27 -0700354 * This function is called when a request is finished. Either a reply
Miklos Szeredif9a28422006-06-25 05:48:53 -0700355 * has arrived or it was aborted (and not yet sent) or some error
Miklos Szeredif43b1552006-01-16 22:14:26 -0800356 * occurred during communication with userspace, or the device file
Miklos Szeredi51eb01e2006-06-25 05:48:50 -0700357 * was closed. The requester thread is woken up (if still waiting),
358 * the 'end' callback is called if given, else the reference to the
359 * request is released
Miklos Szeredi334f4852005-09-09 13:10:27 -0700360 */
361static void request_end(struct fuse_conn *fc, struct fuse_req *req)
362{
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200363 struct fuse_iqueue *fiq = &fc->iq;
Miklos Szeredi365ae712015-07-01 16:26:06 +0200364
Miklos Szerediefe28002015-07-01 16:26:07 +0200365 if (test_and_set_bit(FR_FINISHED, &req->flags))
Miklos Szeredi365ae712015-07-01 16:26:06 +0200366 return;
Miklos Szeredi365ae712015-07-01 16:26:06 +0200367
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200368 spin_lock(&fiq->waitq.lock);
Miklos Szeredi0d8e84b2015-07-01 16:25:58 +0200369 list_del_init(&req->intr_entry);
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200370 spin_unlock(&fiq->waitq.lock);
Miklos Szeredi33e14b42015-07-01 16:26:01 +0200371 WARN_ON(test_bit(FR_PENDING, &req->flags));
372 WARN_ON(test_bit(FR_SENT, &req->flags));
Miklos Szeredi825d6d32015-07-01 16:25:58 +0200373 if (test_bit(FR_BACKGROUND, &req->flags)) {
Miklos Szerediefe28002015-07-01 16:26:07 +0200374 spin_lock(&fc->lock);
Miklos Szeredi825d6d32015-07-01 16:25:58 +0200375 clear_bit(FR_BACKGROUND, &req->flags);
Maxim Patlasov722d2be2013-03-21 18:02:36 +0400376 if (fc->num_background == fc->max_background)
Miklos Szeredi51eb01e2006-06-25 05:48:50 -0700377 fc->blocked = 0;
Maxim Patlasov722d2be2013-03-21 18:02:36 +0400378
379 /* Wake up next waiter, if any */
Miklos Szeredi3c18ef82013-04-17 21:50:58 +0200380 if (!fc->blocked && waitqueue_active(&fc->blocked_waitq))
Maxim Patlasov722d2be2013-03-21 18:02:36 +0400381 wake_up(&fc->blocked_waitq);
382
Csaba Henk7a6d3c82009-07-01 17:28:41 -0700383 if (fc->num_background == fc->congestion_threshold &&
Tejun Heoa325f9b2009-04-14 10:54:52 +0900384 fc->connected && fc->bdi_initialized) {
Jens Axboe8aa7e842009-07-09 14:52:32 +0200385 clear_bdi_congested(&fc->bdi, BLK_RW_SYNC);
386 clear_bdi_congested(&fc->bdi, BLK_RW_ASYNC);
Miklos Szeredif92b99b2007-10-16 23:30:59 -0700387 }
Miklos Szeredi51eb01e2006-06-25 05:48:50 -0700388 fc->num_background--;
Miklos Szeredid12def12008-02-06 01:38:39 -0800389 fc->active_background--;
390 flush_bg_queue(fc);
Miklos Szerediefe28002015-07-01 16:26:07 +0200391 spin_unlock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700392 }
Miklos Szeredi51eb01e2006-06-25 05:48:50 -0700393 wake_up(&req->waitq);
Miklos Szeredi1e6881c2015-07-01 16:26:07 +0200394 if (req->end)
395 req->end(fc, req);
Tejun Heoe9bb09d2008-11-26 12:03:54 +0100396 fuse_put_request(fc, req);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700397}
398
Miklos Szeredif88996a2015-07-01 16:26:01 +0200399static void queue_interrupt(struct fuse_iqueue *fiq, struct fuse_req *req)
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700400{
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200401 spin_lock(&fiq->waitq.lock);
Miklos Szeredi8f7bb362015-07-01 16:26:03 +0200402 if (list_empty(&req->intr_entry)) {
403 list_add_tail(&req->intr_entry, &fiq->interrupts);
404 wake_up_locked(&fiq->waitq);
405 }
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200406 spin_unlock(&fiq->waitq.lock);
Miklos Szeredif88996a2015-07-01 16:26:01 +0200407 kill_fasync(&fiq->fasync, SIGIO, POLL_IN);
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700408}
409
Miklos Szeredi7c352bd2005-09-09 13:10:39 -0700410static void request_wait_answer(struct fuse_conn *fc, struct fuse_req *req)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700411{
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200412 struct fuse_iqueue *fiq = &fc->iq;
Miklos Szeredic4775262015-07-01 16:26:00 +0200413 int err;
414
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700415 if (!fc->no_interrupt) {
416 /* Any signal may interrupt this */
Miklos Szeredic4775262015-07-01 16:26:00 +0200417 err = wait_event_interruptible(req->waitq,
Miklos Szeredi33e14b42015-07-01 16:26:01 +0200418 test_bit(FR_FINISHED, &req->flags));
Miklos Szeredic4775262015-07-01 16:26:00 +0200419 if (!err)
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700420 return;
421
Miklos Szeredi825d6d32015-07-01 16:25:58 +0200422 set_bit(FR_INTERRUPTED, &req->flags);
Miklos Szeredi8f7bb362015-07-01 16:26:03 +0200423 /* matches barrier in fuse_dev_do_read() */
424 smp_mb__after_atomic();
Miklos Szeredi33e14b42015-07-01 16:26:01 +0200425 if (test_bit(FR_SENT, &req->flags))
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200426 queue_interrupt(fiq, req);
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700427 }
428
Miklos Szeredi825d6d32015-07-01 16:25:58 +0200429 if (!test_bit(FR_FORCE, &req->flags)) {
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700430 /* Only fatal signals may interrupt this */
Al Viro7d3a07f2016-07-19 03:08:27 -0400431 err = wait_event_killable(req->waitq,
Miklos Szeredi33e14b42015-07-01 16:26:01 +0200432 test_bit(FR_FINISHED, &req->flags));
Miklos Szeredic4775262015-07-01 16:26:00 +0200433 if (!err)
Miklos Szeredia131de02007-10-16 23:31:04 -0700434 return;
435
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200436 spin_lock(&fiq->waitq.lock);
Miklos Szeredia131de02007-10-16 23:31:04 -0700437 /* Request is not yet in userspace, bail out */
Miklos Szeredi33e14b42015-07-01 16:26:01 +0200438 if (test_bit(FR_PENDING, &req->flags)) {
Miklos Szeredia131de02007-10-16 23:31:04 -0700439 list_del(&req->list);
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200440 spin_unlock(&fiq->waitq.lock);
Miklos Szeredia131de02007-10-16 23:31:04 -0700441 __fuse_put_request(req);
442 req->out.h.error = -EINTR;
443 return;
444 }
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200445 spin_unlock(&fiq->waitq.lock);
Miklos Szeredi51eb01e2006-06-25 05:48:50 -0700446 }
Miklos Szeredi334f4852005-09-09 13:10:27 -0700447
Miklos Szeredia131de02007-10-16 23:31:04 -0700448 /*
449 * Either request is already in userspace, or it was forced.
450 * Wait it out.
451 */
Miklos Szeredi33e14b42015-07-01 16:26:01 +0200452 wait_event(req->waitq, test_bit(FR_FINISHED, &req->flags));
Miklos Szeredi334f4852005-09-09 13:10:27 -0700453}
454
Eric Wong6a4e9222013-02-04 13:04:44 +0000455static void __fuse_request_send(struct fuse_conn *fc, struct fuse_req *req)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700456{
Miklos Szeredie16714d2015-07-01 16:26:01 +0200457 struct fuse_iqueue *fiq = &fc->iq;
458
Miklos Szeredi825d6d32015-07-01 16:25:58 +0200459 BUG_ON(test_bit(FR_BACKGROUND, &req->flags));
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200460 spin_lock(&fiq->waitq.lock);
Miklos Szeredie16714d2015-07-01 16:26:01 +0200461 if (!fiq->connected) {
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200462 spin_unlock(&fiq->waitq.lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700463 req->out.h.error = -ENOTCONN;
Miklos Szeredic4775262015-07-01 16:26:00 +0200464 } else {
Miklos Szeredif88996a2015-07-01 16:26:01 +0200465 req->in.h.unique = fuse_get_unique(fiq);
466 queue_request(fiq, req);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700467 /* acquire extra reference, since request is still needed
468 after request_end() */
469 __fuse_get_request(req);
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200470 spin_unlock(&fiq->waitq.lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700471
Miklos Szeredi7c352bd2005-09-09 13:10:39 -0700472 request_wait_answer(fc, req);
Miklos Szeredic4775262015-07-01 16:26:00 +0200473 /* Pairs with smp_wmb() in request_end() */
474 smp_rmb();
Miklos Szeredi334f4852005-09-09 13:10:27 -0700475 }
Miklos Szeredi334f4852005-09-09 13:10:27 -0700476}
Eric Wong6a4e9222013-02-04 13:04:44 +0000477
478void fuse_request_send(struct fuse_conn *fc, struct fuse_req *req)
479{
Miklos Szeredi825d6d32015-07-01 16:25:58 +0200480 __set_bit(FR_ISREPLY, &req->flags);
481 if (!test_bit(FR_WAITING, &req->flags)) {
482 __set_bit(FR_WAITING, &req->flags);
Miklos Szeredi5437f242015-07-01 16:25:56 +0200483 atomic_inc(&fc->num_waiting);
484 }
Eric Wong6a4e9222013-02-04 13:04:44 +0000485 __fuse_request_send(fc, req);
486}
Tejun Heo08cbf542009-04-14 10:54:53 +0900487EXPORT_SYMBOL_GPL(fuse_request_send);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700488
Miklos Szeredi21f62172015-01-06 10:45:35 +0100489static void fuse_adjust_compat(struct fuse_conn *fc, struct fuse_args *args)
490{
491 if (fc->minor < 4 && args->in.h.opcode == FUSE_STATFS)
492 args->out.args[0].size = FUSE_COMPAT_STATFS_SIZE;
493
494 if (fc->minor < 9) {
495 switch (args->in.h.opcode) {
496 case FUSE_LOOKUP:
497 case FUSE_CREATE:
498 case FUSE_MKNOD:
499 case FUSE_MKDIR:
500 case FUSE_SYMLINK:
501 case FUSE_LINK:
502 args->out.args[0].size = FUSE_COMPAT_ENTRY_OUT_SIZE;
503 break;
504 case FUSE_GETATTR:
505 case FUSE_SETATTR:
506 args->out.args[0].size = FUSE_COMPAT_ATTR_OUT_SIZE;
507 break;
508 }
509 }
510 if (fc->minor < 12) {
511 switch (args->in.h.opcode) {
512 case FUSE_CREATE:
513 args->in.args[0].size = sizeof(struct fuse_open_in);
514 break;
515 case FUSE_MKNOD:
516 args->in.args[0].size = FUSE_COMPAT_MKNOD_IN_SIZE;
517 break;
518 }
519 }
520}
521
Miklos Szeredi70781872014-12-12 09:49:05 +0100522ssize_t fuse_simple_request(struct fuse_conn *fc, struct fuse_args *args)
523{
524 struct fuse_req *req;
525 ssize_t ret;
526
527 req = fuse_get_req(fc, 0);
528 if (IS_ERR(req))
529 return PTR_ERR(req);
530
Miklos Szeredi21f62172015-01-06 10:45:35 +0100531 /* Needs to be done after fuse_get_req() so that fc->minor is valid */
532 fuse_adjust_compat(fc, args);
533
Miklos Szeredi70781872014-12-12 09:49:05 +0100534 req->in.h.opcode = args->in.h.opcode;
535 req->in.h.nodeid = args->in.h.nodeid;
536 req->in.numargs = args->in.numargs;
537 memcpy(req->in.args, args->in.args,
538 args->in.numargs * sizeof(struct fuse_in_arg));
539 req->out.argvar = args->out.argvar;
540 req->out.numargs = args->out.numargs;
541 memcpy(req->out.args, args->out.args,
542 args->out.numargs * sizeof(struct fuse_arg));
543 fuse_request_send(fc, req);
544 ret = req->out.h.error;
545 if (!ret && args->out.argvar) {
546 BUG_ON(args->out.numargs != 1);
547 ret = req->out.args[0].size;
548 }
549 fuse_put_request(fc, req);
550
551 return ret;
552}
553
Miklos Szeredif0139aa2015-07-01 16:25:57 +0200554/*
555 * Called under fc->lock
556 *
557 * fc->connected must have been checked previously
558 */
559void fuse_request_send_background_locked(struct fuse_conn *fc,
560 struct fuse_req *req)
Miklos Szeredid12def12008-02-06 01:38:39 -0800561{
Miklos Szeredi825d6d32015-07-01 16:25:58 +0200562 BUG_ON(!test_bit(FR_BACKGROUND, &req->flags));
563 if (!test_bit(FR_WAITING, &req->flags)) {
564 __set_bit(FR_WAITING, &req->flags);
Miklos Szeredi5437f242015-07-01 16:25:56 +0200565 atomic_inc(&fc->num_waiting);
566 }
Miklos Szeredi825d6d32015-07-01 16:25:58 +0200567 __set_bit(FR_ISREPLY, &req->flags);
Miklos Szeredid12def12008-02-06 01:38:39 -0800568 fc->num_background++;
Csaba Henk7a6d3c82009-07-01 17:28:41 -0700569 if (fc->num_background == fc->max_background)
Miklos Szeredid12def12008-02-06 01:38:39 -0800570 fc->blocked = 1;
Csaba Henk7a6d3c82009-07-01 17:28:41 -0700571 if (fc->num_background == fc->congestion_threshold &&
Tejun Heoa325f9b2009-04-14 10:54:52 +0900572 fc->bdi_initialized) {
Jens Axboe8aa7e842009-07-09 14:52:32 +0200573 set_bdi_congested(&fc->bdi, BLK_RW_SYNC);
574 set_bdi_congested(&fc->bdi, BLK_RW_ASYNC);
Miklos Szeredid12def12008-02-06 01:38:39 -0800575 }
576 list_add_tail(&req->list, &fc->bg_queue);
577 flush_bg_queue(fc);
578}
579
Miklos Szeredif0139aa2015-07-01 16:25:57 +0200580void fuse_request_send_background(struct fuse_conn *fc, struct fuse_req *req)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700581{
Miklos Szeredi42dc6212015-07-01 16:25:56 +0200582 BUG_ON(!req->end);
Miklos Szeredid7133112006-04-10 22:54:55 -0700583 spin_lock(&fc->lock);
Miklos Szeredi1e9a4ed2005-09-09 13:10:31 -0700584 if (fc->connected) {
Miklos Szeredif0139aa2015-07-01 16:25:57 +0200585 fuse_request_send_background_locked(fc, req);
Miklos Szeredid7133112006-04-10 22:54:55 -0700586 spin_unlock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700587 } else {
Miklos Szeredi42dc6212015-07-01 16:25:56 +0200588 spin_unlock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700589 req->out.h.error = -ENOTCONN;
Miklos Szeredi42dc6212015-07-01 16:25:56 +0200590 req->end(fc, req);
591 fuse_put_request(fc, req);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700592 }
593}
Tejun Heo08cbf542009-04-14 10:54:53 +0900594EXPORT_SYMBOL_GPL(fuse_request_send_background);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700595
Miklos Szeredi2d45ba32010-07-12 14:41:40 +0200596static int fuse_request_send_notify_reply(struct fuse_conn *fc,
597 struct fuse_req *req, u64 unique)
598{
599 int err = -ENODEV;
Miklos Szeredif88996a2015-07-01 16:26:01 +0200600 struct fuse_iqueue *fiq = &fc->iq;
Miklos Szeredi2d45ba32010-07-12 14:41:40 +0200601
Miklos Szeredi825d6d32015-07-01 16:25:58 +0200602 __clear_bit(FR_ISREPLY, &req->flags);
Miklos Szeredi2d45ba32010-07-12 14:41:40 +0200603 req->in.h.unique = unique;
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200604 spin_lock(&fiq->waitq.lock);
Miklos Szeredie16714d2015-07-01 16:26:01 +0200605 if (fiq->connected) {
Miklos Szeredif88996a2015-07-01 16:26:01 +0200606 queue_request(fiq, req);
Miklos Szeredi2d45ba32010-07-12 14:41:40 +0200607 err = 0;
608 }
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200609 spin_unlock(&fiq->waitq.lock);
Miklos Szeredi2d45ba32010-07-12 14:41:40 +0200610
611 return err;
612}
613
Anand V. Avati0b05b182012-08-19 08:53:23 -0400614void fuse_force_forget(struct file *file, u64 nodeid)
615{
Al Viro6131ffa2013-02-27 16:59:05 -0500616 struct inode *inode = file_inode(file);
Anand V. Avati0b05b182012-08-19 08:53:23 -0400617 struct fuse_conn *fc = get_fuse_conn(inode);
618 struct fuse_req *req;
619 struct fuse_forget_in inarg;
620
621 memset(&inarg, 0, sizeof(inarg));
622 inarg.nlookup = 1;
Maxim Patlasovb111c8c2012-10-26 19:48:30 +0400623 req = fuse_get_req_nofail_nopages(fc, file);
Anand V. Avati0b05b182012-08-19 08:53:23 -0400624 req->in.h.opcode = FUSE_FORGET;
625 req->in.h.nodeid = nodeid;
626 req->in.numargs = 1;
627 req->in.args[0].size = sizeof(inarg);
628 req->in.args[0].value = &inarg;
Miklos Szeredi825d6d32015-07-01 16:25:58 +0200629 __clear_bit(FR_ISREPLY, &req->flags);
Eric Wong6a4e9222013-02-04 13:04:44 +0000630 __fuse_request_send(fc, req);
631 /* ignore errors */
632 fuse_put_request(fc, req);
Anand V. Avati0b05b182012-08-19 08:53:23 -0400633}
634
Miklos Szeredi3be5a522008-04-30 00:54:41 -0700635/*
Miklos Szeredi334f4852005-09-09 13:10:27 -0700636 * Lock the request. Up to the next unlock_request() there mustn't be
637 * anything that could cause a page-fault. If the request was already
Miklos Szeredif9a28422006-06-25 05:48:53 -0700638 * aborted bail out.
Miklos Szeredi334f4852005-09-09 13:10:27 -0700639 */
Miklos Szeredidc008092015-07-01 16:25:58 +0200640static int lock_request(struct fuse_req *req)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700641{
642 int err = 0;
643 if (req) {
Miklos Szeredidc008092015-07-01 16:25:58 +0200644 spin_lock(&req->waitq.lock);
Miklos Szeredi825d6d32015-07-01 16:25:58 +0200645 if (test_bit(FR_ABORTED, &req->flags))
Miklos Szeredi334f4852005-09-09 13:10:27 -0700646 err = -ENOENT;
647 else
Miklos Szeredi825d6d32015-07-01 16:25:58 +0200648 set_bit(FR_LOCKED, &req->flags);
Miklos Szeredidc008092015-07-01 16:25:58 +0200649 spin_unlock(&req->waitq.lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700650 }
651 return err;
652}
653
654/*
Miklos Szeredi0d8e84b2015-07-01 16:25:58 +0200655 * Unlock request. If it was aborted while locked, caller is responsible
656 * for unlocking and ending the request.
Miklos Szeredi334f4852005-09-09 13:10:27 -0700657 */
Miklos Szeredidc008092015-07-01 16:25:58 +0200658static int unlock_request(struct fuse_req *req)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700659{
Miklos Szeredi0d8e84b2015-07-01 16:25:58 +0200660 int err = 0;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700661 if (req) {
Miklos Szeredidc008092015-07-01 16:25:58 +0200662 spin_lock(&req->waitq.lock);
Miklos Szeredi825d6d32015-07-01 16:25:58 +0200663 if (test_bit(FR_ABORTED, &req->flags))
Miklos Szeredi0d8e84b2015-07-01 16:25:58 +0200664 err = -ENOENT;
665 else
Miklos Szeredi825d6d32015-07-01 16:25:58 +0200666 clear_bit(FR_LOCKED, &req->flags);
Miklos Szeredidc008092015-07-01 16:25:58 +0200667 spin_unlock(&req->waitq.lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700668 }
Miklos Szeredi0d8e84b2015-07-01 16:25:58 +0200669 return err;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700670}
671
672struct fuse_copy_state {
673 int write;
674 struct fuse_req *req;
Al Viro6c09e942015-04-03 22:06:08 -0400675 struct iov_iter *iter;
Miklos Szeredidd3bb142010-05-25 15:06:06 +0200676 struct pipe_buffer *pipebufs;
677 struct pipe_buffer *currbuf;
678 struct pipe_inode_info *pipe;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700679 unsigned long nr_segs;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700680 struct page *pg;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700681 unsigned len;
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200682 unsigned offset;
Miklos Szeredice534fb2010-05-25 15:06:07 +0200683 unsigned move_pages:1;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700684};
685
Miklos Szeredidc008092015-07-01 16:25:58 +0200686static void fuse_copy_init(struct fuse_copy_state *cs, int write,
Al Viro6c09e942015-04-03 22:06:08 -0400687 struct iov_iter *iter)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700688{
689 memset(cs, 0, sizeof(*cs));
690 cs->write = write;
Al Viro6c09e942015-04-03 22:06:08 -0400691 cs->iter = iter;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700692}
693
694/* Unmap and put previous page of userspace buffer */
Miklos Szeredi8bfc0162006-01-16 22:14:28 -0800695static void fuse_copy_finish(struct fuse_copy_state *cs)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700696{
Miklos Szeredidd3bb142010-05-25 15:06:06 +0200697 if (cs->currbuf) {
698 struct pipe_buffer *buf = cs->currbuf;
699
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200700 if (cs->write)
Miklos Szeredic3021622010-05-25 15:06:07 +0200701 buf->len = PAGE_SIZE - cs->len;
Miklos Szeredidd3bb142010-05-25 15:06:06 +0200702 cs->currbuf = NULL;
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200703 } else if (cs->pg) {
Miklos Szeredi334f4852005-09-09 13:10:27 -0700704 if (cs->write) {
705 flush_dcache_page(cs->pg);
706 set_page_dirty_lock(cs->pg);
707 }
708 put_page(cs->pg);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700709 }
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200710 cs->pg = NULL;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700711}
712
713/*
714 * Get another pagefull of userspace buffer, and map it to kernel
715 * address space, and lock request
716 */
717static int fuse_copy_fill(struct fuse_copy_state *cs)
718{
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200719 struct page *page;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700720 int err;
721
Miklos Szeredidc008092015-07-01 16:25:58 +0200722 err = unlock_request(cs->req);
Miklos Szeredi0d8e84b2015-07-01 16:25:58 +0200723 if (err)
724 return err;
725
Miklos Szeredi334f4852005-09-09 13:10:27 -0700726 fuse_copy_finish(cs);
Miklos Szeredidd3bb142010-05-25 15:06:06 +0200727 if (cs->pipebufs) {
728 struct pipe_buffer *buf = cs->pipebufs;
729
Miklos Szeredic3021622010-05-25 15:06:07 +0200730 if (!cs->write) {
731 err = buf->ops->confirm(cs->pipe, buf);
732 if (err)
733 return err;
Miklos Szeredidd3bb142010-05-25 15:06:06 +0200734
Miklos Szeredic3021622010-05-25 15:06:07 +0200735 BUG_ON(!cs->nr_segs);
736 cs->currbuf = buf;
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200737 cs->pg = buf->page;
738 cs->offset = buf->offset;
Miklos Szeredic3021622010-05-25 15:06:07 +0200739 cs->len = buf->len;
Miklos Szeredic3021622010-05-25 15:06:07 +0200740 cs->pipebufs++;
741 cs->nr_segs--;
742 } else {
Miklos Szeredic3021622010-05-25 15:06:07 +0200743 if (cs->nr_segs == cs->pipe->buffers)
744 return -EIO;
745
746 page = alloc_page(GFP_HIGHUSER);
747 if (!page)
748 return -ENOMEM;
749
750 buf->page = page;
751 buf->offset = 0;
752 buf->len = 0;
753
754 cs->currbuf = buf;
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200755 cs->pg = page;
756 cs->offset = 0;
Miklos Szeredic3021622010-05-25 15:06:07 +0200757 cs->len = PAGE_SIZE;
758 cs->pipebufs++;
759 cs->nr_segs++;
760 }
Miklos Szeredidd3bb142010-05-25 15:06:06 +0200761 } else {
Al Viro6c09e942015-04-03 22:06:08 -0400762 size_t off;
763 err = iov_iter_get_pages(cs->iter, &page, PAGE_SIZE, 1, &off);
Miklos Szeredidd3bb142010-05-25 15:06:06 +0200764 if (err < 0)
765 return err;
Al Viro6c09e942015-04-03 22:06:08 -0400766 BUG_ON(!err);
767 cs->len = err;
768 cs->offset = off;
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200769 cs->pg = page;
Al Viro6c09e942015-04-03 22:06:08 -0400770 cs->offset = off;
771 iov_iter_advance(cs->iter, err);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700772 }
Miklos Szeredi334f4852005-09-09 13:10:27 -0700773
Miklos Szeredidc008092015-07-01 16:25:58 +0200774 return lock_request(cs->req);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700775}
776
777/* Do as much copy to/from userspace buffer as we can */
Miklos Szeredi8bfc0162006-01-16 22:14:28 -0800778static int fuse_copy_do(struct fuse_copy_state *cs, void **val, unsigned *size)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700779{
780 unsigned ncpy = min(*size, cs->len);
781 if (val) {
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200782 void *pgaddr = kmap_atomic(cs->pg);
783 void *buf = pgaddr + cs->offset;
784
Miklos Szeredi334f4852005-09-09 13:10:27 -0700785 if (cs->write)
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200786 memcpy(buf, *val, ncpy);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700787 else
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200788 memcpy(*val, buf, ncpy);
789
790 kunmap_atomic(pgaddr);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700791 *val += ncpy;
792 }
793 *size -= ncpy;
794 cs->len -= ncpy;
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200795 cs->offset += ncpy;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700796 return ncpy;
797}
798
Miklos Szeredice534fb2010-05-25 15:06:07 +0200799static int fuse_check_page(struct page *page)
800{
801 if (page_mapcount(page) ||
802 page->mapping != NULL ||
803 page_count(page) != 1 ||
804 (page->flags & PAGE_FLAGS_CHECK_AT_PREP &
805 ~(1 << PG_locked |
806 1 << PG_referenced |
807 1 << PG_uptodate |
808 1 << PG_lru |
809 1 << PG_active |
810 1 << PG_reclaim))) {
811 printk(KERN_WARNING "fuse: trying to steal weird page\n");
812 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);
813 return 1;
814 }
815 return 0;
816}
817
818static int fuse_try_move_page(struct fuse_copy_state *cs, struct page **pagep)
819{
820 int err;
821 struct page *oldpage = *pagep;
822 struct page *newpage;
823 struct pipe_buffer *buf = cs->pipebufs;
Miklos Szeredice534fb2010-05-25 15:06:07 +0200824
Miklos Szeredidc008092015-07-01 16:25:58 +0200825 err = unlock_request(cs->req);
Miklos Szeredi0d8e84b2015-07-01 16:25:58 +0200826 if (err)
827 return err;
828
Miklos Szeredice534fb2010-05-25 15:06:07 +0200829 fuse_copy_finish(cs);
830
831 err = buf->ops->confirm(cs->pipe, buf);
832 if (err)
833 return err;
834
835 BUG_ON(!cs->nr_segs);
836 cs->currbuf = buf;
837 cs->len = buf->len;
838 cs->pipebufs++;
839 cs->nr_segs--;
840
841 if (cs->len != PAGE_SIZE)
842 goto out_fallback;
843
844 if (buf->ops->steal(cs->pipe, buf) != 0)
845 goto out_fallback;
846
847 newpage = buf->page;
848
Miklos Szerediaa991b32015-02-26 11:45:47 +0100849 if (!PageUptodate(newpage))
850 SetPageUptodate(newpage);
Miklos Szeredice534fb2010-05-25 15:06:07 +0200851
852 ClearPageMappedToDisk(newpage);
853
854 if (fuse_check_page(newpage) != 0)
855 goto out_fallback_unlock;
856
Miklos Szeredice534fb2010-05-25 15:06:07 +0200857 /*
858 * This is a new and locked page, it shouldn't be mapped or
859 * have any special flags on it
860 */
861 if (WARN_ON(page_mapped(oldpage)))
862 goto out_fallback_unlock;
863 if (WARN_ON(page_has_private(oldpage)))
864 goto out_fallback_unlock;
865 if (WARN_ON(PageDirty(oldpage) || PageWriteback(oldpage)))
866 goto out_fallback_unlock;
867 if (WARN_ON(PageMlocked(oldpage)))
868 goto out_fallback_unlock;
869
Miklos Szeredief6a3c62011-03-22 16:30:52 -0700870 err = replace_page_cache_page(oldpage, newpage, GFP_KERNEL);
Miklos Szeredice534fb2010-05-25 15:06:07 +0200871 if (err) {
Miklos Szeredief6a3c62011-03-22 16:30:52 -0700872 unlock_page(newpage);
873 return err;
Miklos Szeredice534fb2010-05-25 15:06:07 +0200874 }
Miklos Szeredief6a3c62011-03-22 16:30:52 -0700875
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +0300876 get_page(newpage);
Miklos Szeredice534fb2010-05-25 15:06:07 +0200877
878 if (!(buf->flags & PIPE_BUF_FLAG_LRU))
879 lru_cache_add_file(newpage);
880
881 err = 0;
Miklos Szeredidc008092015-07-01 16:25:58 +0200882 spin_lock(&cs->req->waitq.lock);
Miklos Szeredi825d6d32015-07-01 16:25:58 +0200883 if (test_bit(FR_ABORTED, &cs->req->flags))
Miklos Szeredice534fb2010-05-25 15:06:07 +0200884 err = -ENOENT;
885 else
886 *pagep = newpage;
Miklos Szeredidc008092015-07-01 16:25:58 +0200887 spin_unlock(&cs->req->waitq.lock);
Miklos Szeredice534fb2010-05-25 15:06:07 +0200888
889 if (err) {
890 unlock_page(newpage);
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +0300891 put_page(newpage);
Miklos Szeredice534fb2010-05-25 15:06:07 +0200892 return err;
893 }
894
895 unlock_page(oldpage);
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +0300896 put_page(oldpage);
Miklos Szeredice534fb2010-05-25 15:06:07 +0200897 cs->len = 0;
898
899 return 0;
900
901out_fallback_unlock:
902 unlock_page(newpage);
903out_fallback:
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200904 cs->pg = buf->page;
905 cs->offset = buf->offset;
Miklos Szeredice534fb2010-05-25 15:06:07 +0200906
Miklos Szeredidc008092015-07-01 16:25:58 +0200907 err = lock_request(cs->req);
Miklos Szeredice534fb2010-05-25 15:06:07 +0200908 if (err)
909 return err;
910
911 return 1;
912}
913
Miklos Szeredic3021622010-05-25 15:06:07 +0200914static int fuse_ref_page(struct fuse_copy_state *cs, struct page *page,
915 unsigned offset, unsigned count)
916{
917 struct pipe_buffer *buf;
Miklos Szeredi0d8e84b2015-07-01 16:25:58 +0200918 int err;
Miklos Szeredic3021622010-05-25 15:06:07 +0200919
920 if (cs->nr_segs == cs->pipe->buffers)
921 return -EIO;
922
Miklos Szeredidc008092015-07-01 16:25:58 +0200923 err = unlock_request(cs->req);
Miklos Szeredi0d8e84b2015-07-01 16:25:58 +0200924 if (err)
925 return err;
926
Miklos Szeredic3021622010-05-25 15:06:07 +0200927 fuse_copy_finish(cs);
928
929 buf = cs->pipebufs;
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +0300930 get_page(page);
Miklos Szeredic3021622010-05-25 15:06:07 +0200931 buf->page = page;
932 buf->offset = offset;
933 buf->len = count;
934
935 cs->pipebufs++;
936 cs->nr_segs++;
937 cs->len = 0;
938
939 return 0;
940}
941
Miklos Szeredi334f4852005-09-09 13:10:27 -0700942/*
943 * Copy a page in the request to/from the userspace buffer. Must be
944 * done atomically
945 */
Miklos Szeredice534fb2010-05-25 15:06:07 +0200946static int fuse_copy_page(struct fuse_copy_state *cs, struct page **pagep,
Miklos Szeredi8bfc0162006-01-16 22:14:28 -0800947 unsigned offset, unsigned count, int zeroing)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700948{
Miklos Szeredice534fb2010-05-25 15:06:07 +0200949 int err;
950 struct page *page = *pagep;
951
Miklos Szeredib6777c42010-10-26 14:22:27 -0700952 if (page && zeroing && count < PAGE_SIZE)
953 clear_highpage(page);
954
Miklos Szeredi334f4852005-09-09 13:10:27 -0700955 while (count) {
Miklos Szeredic3021622010-05-25 15:06:07 +0200956 if (cs->write && cs->pipebufs && page) {
957 return fuse_ref_page(cs, page, offset, count);
958 } else if (!cs->len) {
Miklos Szeredice534fb2010-05-25 15:06:07 +0200959 if (cs->move_pages && page &&
960 offset == 0 && count == PAGE_SIZE) {
961 err = fuse_try_move_page(cs, pagep);
962 if (err <= 0)
963 return err;
964 } else {
965 err = fuse_copy_fill(cs);
966 if (err)
967 return err;
968 }
Miklos Szeredi1729a162008-11-26 12:03:54 +0100969 }
Miklos Szeredi334f4852005-09-09 13:10:27 -0700970 if (page) {
Cong Wang2408f6e2011-11-25 23:14:30 +0800971 void *mapaddr = kmap_atomic(page);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700972 void *buf = mapaddr + offset;
973 offset += fuse_copy_do(cs, &buf, &count);
Cong Wang2408f6e2011-11-25 23:14:30 +0800974 kunmap_atomic(mapaddr);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700975 } else
976 offset += fuse_copy_do(cs, NULL, &count);
977 }
978 if (page && !cs->write)
979 flush_dcache_page(page);
980 return 0;
981}
982
983/* Copy pages in the request to/from userspace buffer */
984static int fuse_copy_pages(struct fuse_copy_state *cs, unsigned nbytes,
985 int zeroing)
986{
987 unsigned i;
988 struct fuse_req *req = cs->req;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700989
990 for (i = 0; i < req->num_pages && (nbytes || zeroing); i++) {
Miklos Szeredice534fb2010-05-25 15:06:07 +0200991 int err;
Maxim Patlasov85f40ae2012-10-26 19:49:33 +0400992 unsigned offset = req->page_descs[i].offset;
993 unsigned count = min(nbytes, req->page_descs[i].length);
Miklos Szeredice534fb2010-05-25 15:06:07 +0200994
995 err = fuse_copy_page(cs, &req->pages[i], offset, count,
996 zeroing);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700997 if (err)
998 return err;
999
1000 nbytes -= count;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001001 }
1002 return 0;
1003}
1004
1005/* Copy a single argument in the request to/from userspace buffer */
1006static int fuse_copy_one(struct fuse_copy_state *cs, void *val, unsigned size)
1007{
1008 while (size) {
Miklos Szeredi1729a162008-11-26 12:03:54 +01001009 if (!cs->len) {
1010 int err = fuse_copy_fill(cs);
1011 if (err)
1012 return err;
1013 }
Miklos Szeredi334f4852005-09-09 13:10:27 -07001014 fuse_copy_do(cs, &val, &size);
1015 }
1016 return 0;
1017}
1018
1019/* Copy request arguments to/from userspace buffer */
1020static int fuse_copy_args(struct fuse_copy_state *cs, unsigned numargs,
1021 unsigned argpages, struct fuse_arg *args,
1022 int zeroing)
1023{
1024 int err = 0;
1025 unsigned i;
1026
1027 for (i = 0; !err && i < numargs; i++) {
1028 struct fuse_arg *arg = &args[i];
1029 if (i == numargs - 1 && argpages)
1030 err = fuse_copy_pages(cs, arg->size, zeroing);
1031 else
1032 err = fuse_copy_one(cs, arg->value, arg->size);
1033 }
1034 return err;
1035}
1036
Miklos Szeredif88996a2015-07-01 16:26:01 +02001037static int forget_pending(struct fuse_iqueue *fiq)
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001038{
Miklos Szeredif88996a2015-07-01 16:26:01 +02001039 return fiq->forget_list_head.next != NULL;
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001040}
1041
Miklos Szeredif88996a2015-07-01 16:26:01 +02001042static int request_pending(struct fuse_iqueue *fiq)
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001043{
Miklos Szeredif88996a2015-07-01 16:26:01 +02001044 return !list_empty(&fiq->pending) || !list_empty(&fiq->interrupts) ||
1045 forget_pending(fiq);
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001046}
1047
Miklos Szeredi334f4852005-09-09 13:10:27 -07001048/*
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001049 * Transfer an interrupt request to userspace
1050 *
1051 * Unlike other requests this is assembled on demand, without a need
1052 * to allocate a separate fuse_req structure.
1053 *
Miklos Szeredifd22d622015-07-01 16:26:03 +02001054 * Called with fiq->waitq.lock held, releases it
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001055 */
Miklos Szeredifd22d622015-07-01 16:26:03 +02001056static int fuse_read_interrupt(struct fuse_iqueue *fiq,
1057 struct fuse_copy_state *cs,
Miklos Szeredic3021622010-05-25 15:06:07 +02001058 size_t nbytes, struct fuse_req *req)
Miklos Szeredifd22d622015-07-01 16:26:03 +02001059__releases(fiq->waitq.lock)
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001060{
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001061 struct fuse_in_header ih;
1062 struct fuse_interrupt_in arg;
1063 unsigned reqsize = sizeof(ih) + sizeof(arg);
1064 int err;
1065
1066 list_del_init(&req->intr_entry);
Miklos Szeredi4ce60812015-07-01 16:26:02 +02001067 req->intr_unique = fuse_get_unique(fiq);
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001068 memset(&ih, 0, sizeof(ih));
1069 memset(&arg, 0, sizeof(arg));
1070 ih.len = reqsize;
1071 ih.opcode = FUSE_INTERRUPT;
1072 ih.unique = req->intr_unique;
1073 arg.unique = req->in.h.unique;
1074
Miklos Szeredi4ce60812015-07-01 16:26:02 +02001075 spin_unlock(&fiq->waitq.lock);
Miklos Szeredic3021622010-05-25 15:06:07 +02001076 if (nbytes < reqsize)
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001077 return -EINVAL;
1078
Miklos Szeredic3021622010-05-25 15:06:07 +02001079 err = fuse_copy_one(cs, &ih, sizeof(ih));
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001080 if (!err)
Miklos Szeredic3021622010-05-25 15:06:07 +02001081 err = fuse_copy_one(cs, &arg, sizeof(arg));
1082 fuse_copy_finish(cs);
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001083
1084 return err ? err : reqsize;
1085}
1086
Miklos Szeredif88996a2015-07-01 16:26:01 +02001087static struct fuse_forget_link *dequeue_forget(struct fuse_iqueue *fiq,
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001088 unsigned max,
1089 unsigned *countp)
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001090{
Miklos Szeredif88996a2015-07-01 16:26:01 +02001091 struct fuse_forget_link *head = fiq->forget_list_head.next;
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001092 struct fuse_forget_link **newhead = &head;
1093 unsigned count;
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001094
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001095 for (count = 0; *newhead != NULL && count < max; count++)
1096 newhead = &(*newhead)->next;
1097
Miklos Szeredif88996a2015-07-01 16:26:01 +02001098 fiq->forget_list_head.next = *newhead;
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001099 *newhead = NULL;
Miklos Szeredif88996a2015-07-01 16:26:01 +02001100 if (fiq->forget_list_head.next == NULL)
1101 fiq->forget_list_tail = &fiq->forget_list_head;
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001102
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001103 if (countp != NULL)
1104 *countp = count;
1105
1106 return head;
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001107}
1108
Miklos Szeredifd22d622015-07-01 16:26:03 +02001109static int fuse_read_single_forget(struct fuse_iqueue *fiq,
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001110 struct fuse_copy_state *cs,
1111 size_t nbytes)
Miklos Szeredifd22d622015-07-01 16:26:03 +02001112__releases(fiq->waitq.lock)
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001113{
1114 int err;
Miklos Szeredif88996a2015-07-01 16:26:01 +02001115 struct fuse_forget_link *forget = dequeue_forget(fiq, 1, NULL);
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001116 struct fuse_forget_in arg = {
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001117 .nlookup = forget->forget_one.nlookup,
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001118 };
1119 struct fuse_in_header ih = {
1120 .opcode = FUSE_FORGET,
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001121 .nodeid = forget->forget_one.nodeid,
Miklos Szeredif88996a2015-07-01 16:26:01 +02001122 .unique = fuse_get_unique(fiq),
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001123 .len = sizeof(ih) + sizeof(arg),
1124 };
1125
Miklos Szeredi4ce60812015-07-01 16:26:02 +02001126 spin_unlock(&fiq->waitq.lock);
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001127 kfree(forget);
1128 if (nbytes < ih.len)
1129 return -EINVAL;
1130
1131 err = fuse_copy_one(cs, &ih, sizeof(ih));
1132 if (!err)
1133 err = fuse_copy_one(cs, &arg, sizeof(arg));
1134 fuse_copy_finish(cs);
1135
1136 if (err)
1137 return err;
1138
1139 return ih.len;
1140}
1141
Miklos Szeredifd22d622015-07-01 16:26:03 +02001142static int fuse_read_batch_forget(struct fuse_iqueue *fiq,
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001143 struct fuse_copy_state *cs, size_t nbytes)
Miklos Szeredifd22d622015-07-01 16:26:03 +02001144__releases(fiq->waitq.lock)
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001145{
1146 int err;
1147 unsigned max_forgets;
1148 unsigned count;
1149 struct fuse_forget_link *head;
1150 struct fuse_batch_forget_in arg = { .count = 0 };
1151 struct fuse_in_header ih = {
1152 .opcode = FUSE_BATCH_FORGET,
Miklos Szeredif88996a2015-07-01 16:26:01 +02001153 .unique = fuse_get_unique(fiq),
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001154 .len = sizeof(ih) + sizeof(arg),
1155 };
1156
1157 if (nbytes < ih.len) {
Miklos Szeredi4ce60812015-07-01 16:26:02 +02001158 spin_unlock(&fiq->waitq.lock);
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001159 return -EINVAL;
1160 }
1161
1162 max_forgets = (nbytes - ih.len) / sizeof(struct fuse_forget_one);
Miklos Szeredif88996a2015-07-01 16:26:01 +02001163 head = dequeue_forget(fiq, max_forgets, &count);
Miklos Szeredi4ce60812015-07-01 16:26:02 +02001164 spin_unlock(&fiq->waitq.lock);
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001165
1166 arg.count = count;
1167 ih.len += count * sizeof(struct fuse_forget_one);
1168 err = fuse_copy_one(cs, &ih, sizeof(ih));
1169 if (!err)
1170 err = fuse_copy_one(cs, &arg, sizeof(arg));
1171
1172 while (head) {
1173 struct fuse_forget_link *forget = head;
1174
1175 if (!err) {
1176 err = fuse_copy_one(cs, &forget->forget_one,
1177 sizeof(forget->forget_one));
1178 }
1179 head = forget->next;
1180 kfree(forget);
1181 }
1182
1183 fuse_copy_finish(cs);
1184
1185 if (err)
1186 return err;
1187
1188 return ih.len;
1189}
1190
Miklos Szeredifd22d622015-07-01 16:26:03 +02001191static int fuse_read_forget(struct fuse_conn *fc, struct fuse_iqueue *fiq,
1192 struct fuse_copy_state *cs,
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001193 size_t nbytes)
Miklos Szeredifd22d622015-07-01 16:26:03 +02001194__releases(fiq->waitq.lock)
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001195{
Miklos Szeredif88996a2015-07-01 16:26:01 +02001196 if (fc->minor < 16 || fiq->forget_list_head.next->next == NULL)
Miklos Szeredifd22d622015-07-01 16:26:03 +02001197 return fuse_read_single_forget(fiq, cs, nbytes);
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001198 else
Miklos Szeredifd22d622015-07-01 16:26:03 +02001199 return fuse_read_batch_forget(fiq, cs, nbytes);
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001200}
1201
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001202/*
Miklos Szeredi334f4852005-09-09 13:10:27 -07001203 * Read a single request into the userspace filesystem's buffer. This
1204 * function waits until a request is available, then removes it from
1205 * the pending list and copies request data to userspace buffer. If
Miklos Szeredif9a28422006-06-25 05:48:53 -07001206 * no reply is needed (FORGET) or request has been aborted or there
1207 * was an error during the copying then it's finished by calling
Miklos Szeredi334f4852005-09-09 13:10:27 -07001208 * request_end(). Otherwise add it to the processing list, and set
1209 * the 'sent' flag.
1210 */
Miklos Szeredic36960462015-07-01 16:26:09 +02001211static ssize_t fuse_dev_do_read(struct fuse_dev *fud, struct file *file,
Miklos Szeredic3021622010-05-25 15:06:07 +02001212 struct fuse_copy_state *cs, size_t nbytes)
Miklos Szeredi334f4852005-09-09 13:10:27 -07001213{
Miklos Szeredi82cbdcd2015-07-01 16:26:05 +02001214 ssize_t err;
Miklos Szeredic36960462015-07-01 16:26:09 +02001215 struct fuse_conn *fc = fud->fc;
Miklos Szeredif88996a2015-07-01 16:26:01 +02001216 struct fuse_iqueue *fiq = &fc->iq;
Miklos Szeredic36960462015-07-01 16:26:09 +02001217 struct fuse_pqueue *fpq = &fud->pq;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001218 struct fuse_req *req;
1219 struct fuse_in *in;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001220 unsigned reqsize;
1221
Miklos Szeredi1d3d7522006-01-06 00:19:40 -08001222 restart:
Miklos Szeredi4ce60812015-07-01 16:26:02 +02001223 spin_lock(&fiq->waitq.lock);
Jeff Dikee5ac1d12006-04-10 22:54:53 -07001224 err = -EAGAIN;
Miklos Szeredie16714d2015-07-01 16:26:01 +02001225 if ((file->f_flags & O_NONBLOCK) && fiq->connected &&
Miklos Szeredif88996a2015-07-01 16:26:01 +02001226 !request_pending(fiq))
Jeff Dikee5ac1d12006-04-10 22:54:53 -07001227 goto err_unlock;
1228
Miklos Szeredi52509212015-07-01 16:26:03 +02001229 err = wait_event_interruptible_exclusive_locked(fiq->waitq,
1230 !fiq->connected || request_pending(fiq));
1231 if (err)
1232 goto err_unlock;
1233
Miklos Szeredi334f4852005-09-09 13:10:27 -07001234 err = -ENODEV;
Miklos Szeredie16714d2015-07-01 16:26:01 +02001235 if (!fiq->connected)
Miklos Szeredi334f4852005-09-09 13:10:27 -07001236 goto err_unlock;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001237
Miklos Szeredif88996a2015-07-01 16:26:01 +02001238 if (!list_empty(&fiq->interrupts)) {
1239 req = list_entry(fiq->interrupts.next, struct fuse_req,
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001240 intr_entry);
Miklos Szeredifd22d622015-07-01 16:26:03 +02001241 return fuse_read_interrupt(fiq, cs, nbytes, req);
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001242 }
1243
Miklos Szeredif88996a2015-07-01 16:26:01 +02001244 if (forget_pending(fiq)) {
1245 if (list_empty(&fiq->pending) || fiq->forget_batch-- > 0)
Miklos Szeredifd22d622015-07-01 16:26:03 +02001246 return fuse_read_forget(fc, fiq, cs, nbytes);
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001247
Miklos Szeredif88996a2015-07-01 16:26:01 +02001248 if (fiq->forget_batch <= -8)
1249 fiq->forget_batch = 16;
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001250 }
1251
Miklos Szeredif88996a2015-07-01 16:26:01 +02001252 req = list_entry(fiq->pending.next, struct fuse_req, list);
Miklos Szeredi33e14b42015-07-01 16:26:01 +02001253 clear_bit(FR_PENDING, &req->flags);
Miklos Szeredief759252015-07-01 16:26:02 +02001254 list_del_init(&req->list);
Miklos Szeredi4ce60812015-07-01 16:26:02 +02001255 spin_unlock(&fiq->waitq.lock);
1256
Miklos Szeredi334f4852005-09-09 13:10:27 -07001257 in = &req->in;
Miklos Szeredi1d3d7522006-01-06 00:19:40 -08001258 reqsize = in->h.len;
1259 /* If request is too large, reply with an error and restart the read */
Miklos Szeredic3021622010-05-25 15:06:07 +02001260 if (nbytes < reqsize) {
Miklos Szeredi1d3d7522006-01-06 00:19:40 -08001261 req->out.h.error = -EIO;
1262 /* SETXATTR is special, since it may contain too large data */
1263 if (in->h.opcode == FUSE_SETXATTR)
1264 req->out.h.error = -E2BIG;
1265 request_end(fc, req);
1266 goto restart;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001267 }
Miklos Szeredi45a91cb2015-07-01 16:26:06 +02001268 spin_lock(&fpq->lock);
Miklos Szeredi82cbdcd2015-07-01 16:26:05 +02001269 list_add(&req->list, &fpq->io);
Miklos Szeredi45a91cb2015-07-01 16:26:06 +02001270 spin_unlock(&fpq->lock);
Miklos Szeredic3021622010-05-25 15:06:07 +02001271 cs->req = req;
1272 err = fuse_copy_one(cs, &in->h, sizeof(in->h));
Miklos Szeredi1d3d7522006-01-06 00:19:40 -08001273 if (!err)
Miklos Szeredic3021622010-05-25 15:06:07 +02001274 err = fuse_copy_args(cs, in->numargs, in->argpages,
Miklos Szeredi1d3d7522006-01-06 00:19:40 -08001275 (struct fuse_arg *) in->args, 0);
Miklos Szeredic3021622010-05-25 15:06:07 +02001276 fuse_copy_finish(cs);
Miklos Szeredi45a91cb2015-07-01 16:26:06 +02001277 spin_lock(&fpq->lock);
Miklos Szeredi825d6d32015-07-01 16:25:58 +02001278 clear_bit(FR_LOCKED, &req->flags);
Miklos Szeredie96edd92015-07-01 16:26:04 +02001279 if (!fpq->connected) {
Miklos Szeredi82cbdcd2015-07-01 16:26:05 +02001280 err = -ENODEV;
1281 goto out_end;
Miklos Szeredic9c9d7d2007-10-16 23:31:05 -07001282 }
Miklos Szeredi334f4852005-09-09 13:10:27 -07001283 if (err) {
Miklos Szeredic9c9d7d2007-10-16 23:31:05 -07001284 req->out.h.error = -EIO;
Miklos Szeredi82cbdcd2015-07-01 16:26:05 +02001285 goto out_end;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001286 }
Miklos Szeredi825d6d32015-07-01 16:25:58 +02001287 if (!test_bit(FR_ISREPLY, &req->flags)) {
Miklos Szeredi82cbdcd2015-07-01 16:26:05 +02001288 err = reqsize;
1289 goto out_end;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001290 }
Miklos Szeredi82cbdcd2015-07-01 16:26:05 +02001291 list_move_tail(&req->list, &fpq->processing);
Miklos Szeredi45a91cb2015-07-01 16:26:06 +02001292 spin_unlock(&fpq->lock);
Miklos Szeredi82cbdcd2015-07-01 16:26:05 +02001293 set_bit(FR_SENT, &req->flags);
1294 /* matches barrier in request_wait_answer() */
1295 smp_mb__after_atomic();
1296 if (test_bit(FR_INTERRUPTED, &req->flags))
1297 queue_interrupt(fiq, req);
Miklos Szeredi82cbdcd2015-07-01 16:26:05 +02001298
Miklos Szeredi334f4852005-09-09 13:10:27 -07001299 return reqsize;
1300
Miklos Szeredi82cbdcd2015-07-01 16:26:05 +02001301out_end:
Miklos Szeredi77cd9d42015-07-01 16:26:06 +02001302 if (!test_bit(FR_PRIVATE, &req->flags))
1303 list_del_init(&req->list);
Miklos Szeredi45a91cb2015-07-01 16:26:06 +02001304 spin_unlock(&fpq->lock);
Miklos Szeredi82cbdcd2015-07-01 16:26:05 +02001305 request_end(fc, req);
1306 return err;
1307
Miklos Szeredi334f4852005-09-09 13:10:27 -07001308 err_unlock:
Miklos Szeredi4ce60812015-07-01 16:26:02 +02001309 spin_unlock(&fiq->waitq.lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001310 return err;
1311}
1312
Tom Van Braeckel94e4fe22015-01-12 05:22:16 +01001313static int fuse_dev_open(struct inode *inode, struct file *file)
1314{
1315 /*
1316 * The fuse device's file's private_data is used to hold
1317 * the fuse_conn(ection) when it is mounted, and is used to
1318 * keep track of whether the file has been mounted already.
1319 */
1320 file->private_data = NULL;
1321 return 0;
1322}
1323
Al Virofbdbacc2015-04-03 21:53:39 -04001324static ssize_t fuse_dev_read(struct kiocb *iocb, struct iov_iter *to)
Miklos Szeredic3021622010-05-25 15:06:07 +02001325{
1326 struct fuse_copy_state cs;
1327 struct file *file = iocb->ki_filp;
Miklos Szeredicc080e92015-07-01 16:26:08 +02001328 struct fuse_dev *fud = fuse_get_dev(file);
1329
1330 if (!fud)
Miklos Szeredic3021622010-05-25 15:06:07 +02001331 return -EPERM;
1332
Al Virofbdbacc2015-04-03 21:53:39 -04001333 if (!iter_is_iovec(to))
1334 return -EINVAL;
Miklos Szeredic3021622010-05-25 15:06:07 +02001335
Miklos Szeredidc008092015-07-01 16:25:58 +02001336 fuse_copy_init(&cs, 1, to);
Al Virofbdbacc2015-04-03 21:53:39 -04001337
Miklos Szeredic36960462015-07-01 16:26:09 +02001338 return fuse_dev_do_read(fud, file, &cs, iov_iter_count(to));
Miklos Szeredic3021622010-05-25 15:06:07 +02001339}
1340
Miklos Szeredic3021622010-05-25 15:06:07 +02001341static ssize_t fuse_dev_splice_read(struct file *in, loff_t *ppos,
1342 struct pipe_inode_info *pipe,
1343 size_t len, unsigned int flags)
1344{
1345 int ret;
1346 int page_nr = 0;
1347 int do_wakeup = 0;
1348 struct pipe_buffer *bufs;
1349 struct fuse_copy_state cs;
Miklos Szeredicc080e92015-07-01 16:26:08 +02001350 struct fuse_dev *fud = fuse_get_dev(in);
1351
1352 if (!fud)
Miklos Szeredic3021622010-05-25 15:06:07 +02001353 return -EPERM;
1354
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001355 bufs = kmalloc(pipe->buffers * sizeof(struct pipe_buffer), GFP_KERNEL);
Miklos Szeredic3021622010-05-25 15:06:07 +02001356 if (!bufs)
1357 return -ENOMEM;
1358
Miklos Szeredidc008092015-07-01 16:25:58 +02001359 fuse_copy_init(&cs, 1, NULL);
Miklos Szeredic3021622010-05-25 15:06:07 +02001360 cs.pipebufs = bufs;
1361 cs.pipe = pipe;
Miklos Szeredic36960462015-07-01 16:26:09 +02001362 ret = fuse_dev_do_read(fud, in, &cs, len);
Miklos Szeredic3021622010-05-25 15:06:07 +02001363 if (ret < 0)
1364 goto out;
1365
1366 ret = 0;
1367 pipe_lock(pipe);
1368
1369 if (!pipe->readers) {
1370 send_sig(SIGPIPE, current, 0);
1371 if (!ret)
1372 ret = -EPIPE;
1373 goto out_unlock;
1374 }
1375
1376 if (pipe->nrbufs + cs.nr_segs > pipe->buffers) {
1377 ret = -EIO;
1378 goto out_unlock;
1379 }
1380
1381 while (page_nr < cs.nr_segs) {
1382 int newbuf = (pipe->curbuf + pipe->nrbufs) & (pipe->buffers - 1);
1383 struct pipe_buffer *buf = pipe->bufs + newbuf;
1384
1385 buf->page = bufs[page_nr].page;
1386 buf->offset = bufs[page_nr].offset;
1387 buf->len = bufs[page_nr].len;
Miklos Szeredi28a625c2014-01-22 19:36:57 +01001388 /*
1389 * Need to be careful about this. Having buf->ops in module
1390 * code can Oops if the buffer persists after module unload.
1391 */
1392 buf->ops = &nosteal_pipe_buf_ops;
Miklos Szeredic3021622010-05-25 15:06:07 +02001393
1394 pipe->nrbufs++;
1395 page_nr++;
1396 ret += buf->len;
1397
Al Viro6447a3c2013-03-21 11:01:38 -04001398 if (pipe->files)
Miklos Szeredic3021622010-05-25 15:06:07 +02001399 do_wakeup = 1;
1400 }
1401
1402out_unlock:
1403 pipe_unlock(pipe);
1404
1405 if (do_wakeup) {
1406 smp_mb();
1407 if (waitqueue_active(&pipe->wait))
1408 wake_up_interruptible(&pipe->wait);
1409 kill_fasync(&pipe->fasync_readers, SIGIO, POLL_IN);
1410 }
1411
1412out:
1413 for (; page_nr < cs.nr_segs; page_nr++)
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +03001414 put_page(bufs[page_nr].page);
Miklos Szeredic3021622010-05-25 15:06:07 +02001415
1416 kfree(bufs);
1417 return ret;
1418}
1419
Tejun Heo95668a62008-11-26 12:03:55 +01001420static int fuse_notify_poll(struct fuse_conn *fc, unsigned int size,
1421 struct fuse_copy_state *cs)
1422{
1423 struct fuse_notify_poll_wakeup_out outarg;
Miklos Szeredif6d47a12009-01-26 15:00:59 +01001424 int err = -EINVAL;
Tejun Heo95668a62008-11-26 12:03:55 +01001425
1426 if (size != sizeof(outarg))
Miklos Szeredif6d47a12009-01-26 15:00:59 +01001427 goto err;
Tejun Heo95668a62008-11-26 12:03:55 +01001428
1429 err = fuse_copy_one(cs, &outarg, sizeof(outarg));
1430 if (err)
Miklos Szeredif6d47a12009-01-26 15:00:59 +01001431 goto err;
Tejun Heo95668a62008-11-26 12:03:55 +01001432
Miklos Szeredif6d47a12009-01-26 15:00:59 +01001433 fuse_copy_finish(cs);
Tejun Heo95668a62008-11-26 12:03:55 +01001434 return fuse_notify_poll_wakeup(fc, &outarg);
Miklos Szeredif6d47a12009-01-26 15:00:59 +01001435
1436err:
1437 fuse_copy_finish(cs);
1438 return err;
Tejun Heo95668a62008-11-26 12:03:55 +01001439}
1440
John Muir3b463ae2009-05-31 11:13:57 -04001441static int fuse_notify_inval_inode(struct fuse_conn *fc, unsigned int size,
1442 struct fuse_copy_state *cs)
1443{
1444 struct fuse_notify_inval_inode_out outarg;
1445 int err = -EINVAL;
1446
1447 if (size != sizeof(outarg))
1448 goto err;
1449
1450 err = fuse_copy_one(cs, &outarg, sizeof(outarg));
1451 if (err)
1452 goto err;
1453 fuse_copy_finish(cs);
1454
1455 down_read(&fc->killsb);
1456 err = -ENOENT;
Miklos Szeredib21dda42010-02-05 12:08:31 +01001457 if (fc->sb) {
1458 err = fuse_reverse_inval_inode(fc->sb, outarg.ino,
1459 outarg.off, outarg.len);
1460 }
John Muir3b463ae2009-05-31 11:13:57 -04001461 up_read(&fc->killsb);
1462 return err;
1463
1464err:
1465 fuse_copy_finish(cs);
1466 return err;
1467}
1468
1469static int fuse_notify_inval_entry(struct fuse_conn *fc, unsigned int size,
1470 struct fuse_copy_state *cs)
1471{
1472 struct fuse_notify_inval_entry_out outarg;
Fang Wenqib2d82ee2009-12-30 18:37:13 +08001473 int err = -ENOMEM;
1474 char *buf;
John Muir3b463ae2009-05-31 11:13:57 -04001475 struct qstr name;
1476
Fang Wenqib2d82ee2009-12-30 18:37:13 +08001477 buf = kzalloc(FUSE_NAME_MAX + 1, GFP_KERNEL);
1478 if (!buf)
1479 goto err;
1480
1481 err = -EINVAL;
John Muir3b463ae2009-05-31 11:13:57 -04001482 if (size < sizeof(outarg))
1483 goto err;
1484
1485 err = fuse_copy_one(cs, &outarg, sizeof(outarg));
1486 if (err)
1487 goto err;
1488
1489 err = -ENAMETOOLONG;
1490 if (outarg.namelen > FUSE_NAME_MAX)
1491 goto err;
1492
Miklos Szeredic2183d12011-08-24 10:20:17 +02001493 err = -EINVAL;
1494 if (size != sizeof(outarg) + outarg.namelen + 1)
1495 goto err;
1496
John Muir3b463ae2009-05-31 11:13:57 -04001497 name.name = buf;
1498 name.len = outarg.namelen;
1499 err = fuse_copy_one(cs, buf, outarg.namelen + 1);
1500 if (err)
1501 goto err;
1502 fuse_copy_finish(cs);
1503 buf[outarg.namelen] = 0;
John Muir3b463ae2009-05-31 11:13:57 -04001504
1505 down_read(&fc->killsb);
1506 err = -ENOENT;
Miklos Szeredib21dda42010-02-05 12:08:31 +01001507 if (fc->sb)
John Muir451d0f52011-12-06 21:50:06 +01001508 err = fuse_reverse_inval_entry(fc->sb, outarg.parent, 0, &name);
1509 up_read(&fc->killsb);
1510 kfree(buf);
1511 return err;
1512
1513err:
1514 kfree(buf);
1515 fuse_copy_finish(cs);
1516 return err;
1517}
1518
1519static int fuse_notify_delete(struct fuse_conn *fc, unsigned int size,
1520 struct fuse_copy_state *cs)
1521{
1522 struct fuse_notify_delete_out outarg;
1523 int err = -ENOMEM;
1524 char *buf;
1525 struct qstr name;
1526
1527 buf = kzalloc(FUSE_NAME_MAX + 1, GFP_KERNEL);
1528 if (!buf)
1529 goto err;
1530
1531 err = -EINVAL;
1532 if (size < sizeof(outarg))
1533 goto err;
1534
1535 err = fuse_copy_one(cs, &outarg, sizeof(outarg));
1536 if (err)
1537 goto err;
1538
1539 err = -ENAMETOOLONG;
1540 if (outarg.namelen > FUSE_NAME_MAX)
1541 goto err;
1542
1543 err = -EINVAL;
1544 if (size != sizeof(outarg) + outarg.namelen + 1)
1545 goto err;
1546
1547 name.name = buf;
1548 name.len = outarg.namelen;
1549 err = fuse_copy_one(cs, buf, outarg.namelen + 1);
1550 if (err)
1551 goto err;
1552 fuse_copy_finish(cs);
1553 buf[outarg.namelen] = 0;
John Muir451d0f52011-12-06 21:50:06 +01001554
1555 down_read(&fc->killsb);
1556 err = -ENOENT;
1557 if (fc->sb)
1558 err = fuse_reverse_inval_entry(fc->sb, outarg.parent,
1559 outarg.child, &name);
John Muir3b463ae2009-05-31 11:13:57 -04001560 up_read(&fc->killsb);
Fang Wenqib2d82ee2009-12-30 18:37:13 +08001561 kfree(buf);
John Muir3b463ae2009-05-31 11:13:57 -04001562 return err;
1563
1564err:
Fang Wenqib2d82ee2009-12-30 18:37:13 +08001565 kfree(buf);
John Muir3b463ae2009-05-31 11:13:57 -04001566 fuse_copy_finish(cs);
1567 return err;
1568}
1569
Miklos Szeredia1d75f22010-07-12 14:41:40 +02001570static int fuse_notify_store(struct fuse_conn *fc, unsigned int size,
1571 struct fuse_copy_state *cs)
1572{
1573 struct fuse_notify_store_out outarg;
1574 struct inode *inode;
1575 struct address_space *mapping;
1576 u64 nodeid;
1577 int err;
1578 pgoff_t index;
1579 unsigned int offset;
1580 unsigned int num;
1581 loff_t file_size;
1582 loff_t end;
1583
1584 err = -EINVAL;
1585 if (size < sizeof(outarg))
1586 goto out_finish;
1587
1588 err = fuse_copy_one(cs, &outarg, sizeof(outarg));
1589 if (err)
1590 goto out_finish;
1591
1592 err = -EINVAL;
1593 if (size - sizeof(outarg) != outarg.size)
1594 goto out_finish;
1595
1596 nodeid = outarg.nodeid;
1597
1598 down_read(&fc->killsb);
1599
1600 err = -ENOENT;
1601 if (!fc->sb)
1602 goto out_up_killsb;
1603
1604 inode = ilookup5(fc->sb, nodeid, fuse_inode_eq, &nodeid);
1605 if (!inode)
1606 goto out_up_killsb;
1607
1608 mapping = inode->i_mapping;
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +03001609 index = outarg.offset >> PAGE_SHIFT;
1610 offset = outarg.offset & ~PAGE_MASK;
Miklos Szeredia1d75f22010-07-12 14:41:40 +02001611 file_size = i_size_read(inode);
1612 end = outarg.offset + outarg.size;
1613 if (end > file_size) {
1614 file_size = end;
1615 fuse_write_update_size(inode, file_size);
1616 }
1617
1618 num = outarg.size;
1619 while (num) {
1620 struct page *page;
1621 unsigned int this_num;
1622
1623 err = -ENOMEM;
1624 page = find_or_create_page(mapping, index,
1625 mapping_gfp_mask(mapping));
1626 if (!page)
1627 goto out_iput;
1628
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +03001629 this_num = min_t(unsigned, num, PAGE_SIZE - offset);
Miklos Szeredia1d75f22010-07-12 14:41:40 +02001630 err = fuse_copy_page(cs, &page, offset, this_num, 0);
Miklos Szeredi063ec1e2014-01-22 19:36:58 +01001631 if (!err && offset == 0 &&
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +03001632 (this_num == PAGE_SIZE || file_size == end))
Miklos Szeredia1d75f22010-07-12 14:41:40 +02001633 SetPageUptodate(page);
1634 unlock_page(page);
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +03001635 put_page(page);
Miklos Szeredia1d75f22010-07-12 14:41:40 +02001636
1637 if (err)
1638 goto out_iput;
1639
1640 num -= this_num;
1641 offset = 0;
1642 index++;
1643 }
1644
1645 err = 0;
1646
1647out_iput:
1648 iput(inode);
1649out_up_killsb:
1650 up_read(&fc->killsb);
1651out_finish:
1652 fuse_copy_finish(cs);
1653 return err;
1654}
1655
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001656static void fuse_retrieve_end(struct fuse_conn *fc, struct fuse_req *req)
1657{
Mel Gormanb745bc82014-06-04 16:10:22 -07001658 release_pages(req->pages, req->num_pages, false);
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001659}
1660
1661static int fuse_retrieve(struct fuse_conn *fc, struct inode *inode,
1662 struct fuse_notify_retrieve_out *outarg)
1663{
1664 int err;
1665 struct address_space *mapping = inode->i_mapping;
1666 struct fuse_req *req;
1667 pgoff_t index;
1668 loff_t file_size;
1669 unsigned int num;
1670 unsigned int offset;
Geert Uytterhoeven01574432010-09-30 22:06:21 +02001671 size_t total_len = 0;
Maxim Patlasov4d53dc92012-10-26 19:48:42 +04001672 int num_pages;
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001673
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +03001674 offset = outarg->offset & ~PAGE_MASK;
Maxim Patlasov4d53dc92012-10-26 19:48:42 +04001675 file_size = i_size_read(inode);
1676
1677 num = outarg->size;
1678 if (outarg->offset > file_size)
1679 num = 0;
1680 else if (outarg->offset + num > file_size)
1681 num = file_size - outarg->offset;
1682
1683 num_pages = (num + offset + PAGE_SIZE - 1) >> PAGE_SHIFT;
1684 num_pages = min(num_pages, FUSE_MAX_PAGES_PER_REQ);
1685
1686 req = fuse_get_req(fc, num_pages);
1687 if (IS_ERR(req))
1688 return PTR_ERR(req);
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001689
1690 req->in.h.opcode = FUSE_NOTIFY_REPLY;
1691 req->in.h.nodeid = outarg->nodeid;
1692 req->in.numargs = 2;
1693 req->in.argpages = 1;
Maxim Patlasovb2430d72012-10-26 19:49:24 +04001694 req->page_descs[0].offset = offset;
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001695 req->end = fuse_retrieve_end;
1696
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +03001697 index = outarg->offset >> PAGE_SHIFT;
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001698
Maxim Patlasov4d53dc92012-10-26 19:48:42 +04001699 while (num && req->num_pages < num_pages) {
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001700 struct page *page;
1701 unsigned int this_num;
1702
1703 page = find_get_page(mapping, index);
1704 if (!page)
1705 break;
1706
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +03001707 this_num = min_t(unsigned, num, PAGE_SIZE - offset);
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001708 req->pages[req->num_pages] = page;
Maxim Patlasov85f40ae2012-10-26 19:49:33 +04001709 req->page_descs[req->num_pages].length = this_num;
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001710 req->num_pages++;
1711
Miklos Szeredic9e67d42012-09-04 18:45:54 +02001712 offset = 0;
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001713 num -= this_num;
1714 total_len += this_num;
Miklos Szeredi48706d02011-12-13 10:36:59 +01001715 index++;
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001716 }
1717 req->misc.retrieve_in.offset = outarg->offset;
1718 req->misc.retrieve_in.size = total_len;
1719 req->in.args[0].size = sizeof(req->misc.retrieve_in);
1720 req->in.args[0].value = &req->misc.retrieve_in;
1721 req->in.args[1].size = total_len;
1722
1723 err = fuse_request_send_notify_reply(fc, req, outarg->notify_unique);
1724 if (err)
1725 fuse_retrieve_end(fc, req);
1726
1727 return err;
1728}
1729
1730static int fuse_notify_retrieve(struct fuse_conn *fc, unsigned int size,
1731 struct fuse_copy_state *cs)
1732{
1733 struct fuse_notify_retrieve_out outarg;
1734 struct inode *inode;
1735 int err;
1736
1737 err = -EINVAL;
1738 if (size != sizeof(outarg))
1739 goto copy_finish;
1740
1741 err = fuse_copy_one(cs, &outarg, sizeof(outarg));
1742 if (err)
1743 goto copy_finish;
1744
1745 fuse_copy_finish(cs);
1746
1747 down_read(&fc->killsb);
1748 err = -ENOENT;
1749 if (fc->sb) {
1750 u64 nodeid = outarg.nodeid;
1751
1752 inode = ilookup5(fc->sb, nodeid, fuse_inode_eq, &nodeid);
1753 if (inode) {
1754 err = fuse_retrieve(fc, inode, &outarg);
1755 iput(inode);
1756 }
1757 }
1758 up_read(&fc->killsb);
1759
1760 return err;
1761
1762copy_finish:
1763 fuse_copy_finish(cs);
1764 return err;
1765}
1766
Tejun Heo85993962008-11-26 12:03:55 +01001767static int fuse_notify(struct fuse_conn *fc, enum fuse_notify_code code,
1768 unsigned int size, struct fuse_copy_state *cs)
1769{
Miklos Szeredi0d278362015-02-26 11:45:47 +01001770 /* Don't try to move pages (yet) */
1771 cs->move_pages = 0;
1772
Tejun Heo85993962008-11-26 12:03:55 +01001773 switch (code) {
Tejun Heo95668a62008-11-26 12:03:55 +01001774 case FUSE_NOTIFY_POLL:
1775 return fuse_notify_poll(fc, size, cs);
1776
John Muir3b463ae2009-05-31 11:13:57 -04001777 case FUSE_NOTIFY_INVAL_INODE:
1778 return fuse_notify_inval_inode(fc, size, cs);
1779
1780 case FUSE_NOTIFY_INVAL_ENTRY:
1781 return fuse_notify_inval_entry(fc, size, cs);
1782
Miklos Szeredia1d75f22010-07-12 14:41:40 +02001783 case FUSE_NOTIFY_STORE:
1784 return fuse_notify_store(fc, size, cs);
1785
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001786 case FUSE_NOTIFY_RETRIEVE:
1787 return fuse_notify_retrieve(fc, size, cs);
1788
John Muir451d0f52011-12-06 21:50:06 +01001789 case FUSE_NOTIFY_DELETE:
1790 return fuse_notify_delete(fc, size, cs);
1791
Tejun Heo85993962008-11-26 12:03:55 +01001792 default:
Miklos Szeredif6d47a12009-01-26 15:00:59 +01001793 fuse_copy_finish(cs);
Tejun Heo85993962008-11-26 12:03:55 +01001794 return -EINVAL;
1795 }
1796}
1797
Miklos Szeredi334f4852005-09-09 13:10:27 -07001798/* Look up request on processing list by unique ID */
Miklos Szeredi3a2b5b92015-07-01 16:26:04 +02001799static struct fuse_req *request_find(struct fuse_pqueue *fpq, u64 unique)
Miklos Szeredi334f4852005-09-09 13:10:27 -07001800{
Dong Fang05726ac2013-07-30 22:50:01 -04001801 struct fuse_req *req;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001802
Miklos Szeredi3a2b5b92015-07-01 16:26:04 +02001803 list_for_each_entry(req, &fpq->processing, list) {
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001804 if (req->in.h.unique == unique || req->intr_unique == unique)
Miklos Szeredi334f4852005-09-09 13:10:27 -07001805 return req;
1806 }
1807 return NULL;
1808}
1809
1810static int copy_out_args(struct fuse_copy_state *cs, struct fuse_out *out,
1811 unsigned nbytes)
1812{
1813 unsigned reqsize = sizeof(struct fuse_out_header);
1814
1815 if (out->h.error)
1816 return nbytes != reqsize ? -EINVAL : 0;
1817
1818 reqsize += len_args(out->numargs, out->args);
1819
1820 if (reqsize < nbytes || (reqsize > nbytes && !out->argvar))
1821 return -EINVAL;
1822 else if (reqsize > nbytes) {
1823 struct fuse_arg *lastarg = &out->args[out->numargs-1];
1824 unsigned diffsize = reqsize - nbytes;
1825 if (diffsize > lastarg->size)
1826 return -EINVAL;
1827 lastarg->size -= diffsize;
1828 }
1829 return fuse_copy_args(cs, out->numargs, out->argpages, out->args,
1830 out->page_zeroing);
1831}
1832
1833/*
1834 * Write a single reply to a request. First the header is copied from
1835 * the write buffer. The request is then searched on the processing
1836 * list by the unique ID found in the header. If found, then remove
1837 * it from the list and copy the rest of the buffer to the request.
1838 * The request is finished by calling request_end()
1839 */
Miklos Szeredic36960462015-07-01 16:26:09 +02001840static ssize_t fuse_dev_do_write(struct fuse_dev *fud,
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001841 struct fuse_copy_state *cs, size_t nbytes)
Miklos Szeredi334f4852005-09-09 13:10:27 -07001842{
1843 int err;
Miklos Szeredic36960462015-07-01 16:26:09 +02001844 struct fuse_conn *fc = fud->fc;
1845 struct fuse_pqueue *fpq = &fud->pq;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001846 struct fuse_req *req;
1847 struct fuse_out_header oh;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001848
Miklos Szeredi334f4852005-09-09 13:10:27 -07001849 if (nbytes < sizeof(struct fuse_out_header))
1850 return -EINVAL;
1851
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001852 err = fuse_copy_one(cs, &oh, sizeof(oh));
Miklos Szeredi334f4852005-09-09 13:10:27 -07001853 if (err)
1854 goto err_finish;
Tejun Heo85993962008-11-26 12:03:55 +01001855
Miklos Szeredi334f4852005-09-09 13:10:27 -07001856 err = -EINVAL;
Tejun Heo85993962008-11-26 12:03:55 +01001857 if (oh.len != nbytes)
1858 goto err_finish;
1859
1860 /*
1861 * Zero oh.unique indicates unsolicited notification message
1862 * and error contains notification code.
1863 */
1864 if (!oh.unique) {
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001865 err = fuse_notify(fc, oh.error, nbytes - sizeof(oh), cs);
Tejun Heo85993962008-11-26 12:03:55 +01001866 return err ? err : nbytes;
1867 }
1868
1869 err = -EINVAL;
1870 if (oh.error <= -1000 || oh.error > 0)
Miklos Szeredi334f4852005-09-09 13:10:27 -07001871 goto err_finish;
1872
Miklos Szeredi45a91cb2015-07-01 16:26:06 +02001873 spin_lock(&fpq->lock);
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08001874 err = -ENOENT;
Miklos Szeredie96edd92015-07-01 16:26:04 +02001875 if (!fpq->connected)
Miklos Szeredi45a91cb2015-07-01 16:26:06 +02001876 goto err_unlock_pq;
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08001877
Miklos Szeredi3a2b5b92015-07-01 16:26:04 +02001878 req = request_find(fpq, oh.unique);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001879 if (!req)
Miklos Szeredi45a91cb2015-07-01 16:26:06 +02001880 goto err_unlock_pq;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001881
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001882 /* Is it an interrupt reply? */
1883 if (req->intr_unique == oh.unique) {
Miklos Szeredi45a91cb2015-07-01 16:26:06 +02001884 spin_unlock(&fpq->lock);
1885
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001886 err = -EINVAL;
1887 if (nbytes != sizeof(struct fuse_out_header))
Miklos Szeredi46c34a32015-07-01 16:26:07 +02001888 goto err_finish;
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001889
1890 if (oh.error == -ENOSYS)
1891 fc->no_interrupt = 1;
1892 else if (oh.error == -EAGAIN)
Miklos Szeredif88996a2015-07-01 16:26:01 +02001893 queue_interrupt(&fc->iq, req);
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001894
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001895 fuse_copy_finish(cs);
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001896 return nbytes;
1897 }
1898
Miklos Szeredi33e14b42015-07-01 16:26:01 +02001899 clear_bit(FR_SENT, &req->flags);
Miklos Szeredi3a2b5b92015-07-01 16:26:04 +02001900 list_move(&req->list, &fpq->io);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001901 req->out.h = oh;
Miklos Szeredi825d6d32015-07-01 16:25:58 +02001902 set_bit(FR_LOCKED, &req->flags);
Miklos Szeredi45a91cb2015-07-01 16:26:06 +02001903 spin_unlock(&fpq->lock);
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001904 cs->req = req;
Miklos Szeredice534fb2010-05-25 15:06:07 +02001905 if (!req->out.page_replace)
1906 cs->move_pages = 0;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001907
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001908 err = copy_out_args(cs, &req->out, nbytes);
1909 fuse_copy_finish(cs);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001910
Miklos Szeredi45a91cb2015-07-01 16:26:06 +02001911 spin_lock(&fpq->lock);
Miklos Szeredi825d6d32015-07-01 16:25:58 +02001912 clear_bit(FR_LOCKED, &req->flags);
Miklos Szeredie96edd92015-07-01 16:26:04 +02001913 if (!fpq->connected)
Miklos Szeredi0d8e84b2015-07-01 16:25:58 +02001914 err = -ENOENT;
1915 else if (err)
Miklos Szeredi334f4852005-09-09 13:10:27 -07001916 req->out.h.error = -EIO;
Miklos Szeredi77cd9d42015-07-01 16:26:06 +02001917 if (!test_bit(FR_PRIVATE, &req->flags))
1918 list_del_init(&req->list);
Miklos Szeredi45a91cb2015-07-01 16:26:06 +02001919 spin_unlock(&fpq->lock);
Miklos Szeredi46c34a32015-07-01 16:26:07 +02001920
Miklos Szeredi334f4852005-09-09 13:10:27 -07001921 request_end(fc, req);
1922
1923 return err ? err : nbytes;
1924
Miklos Szeredi45a91cb2015-07-01 16:26:06 +02001925 err_unlock_pq:
1926 spin_unlock(&fpq->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001927 err_finish:
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001928 fuse_copy_finish(cs);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001929 return err;
1930}
1931
Al Virofbdbacc2015-04-03 21:53:39 -04001932static ssize_t fuse_dev_write(struct kiocb *iocb, struct iov_iter *from)
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001933{
1934 struct fuse_copy_state cs;
Miklos Szeredicc080e92015-07-01 16:26:08 +02001935 struct fuse_dev *fud = fuse_get_dev(iocb->ki_filp);
1936
1937 if (!fud)
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001938 return -EPERM;
1939
Al Virofbdbacc2015-04-03 21:53:39 -04001940 if (!iter_is_iovec(from))
1941 return -EINVAL;
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001942
Miklos Szeredidc008092015-07-01 16:25:58 +02001943 fuse_copy_init(&cs, 0, from);
Al Virofbdbacc2015-04-03 21:53:39 -04001944
Miklos Szeredic36960462015-07-01 16:26:09 +02001945 return fuse_dev_do_write(fud, &cs, iov_iter_count(from));
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001946}
1947
1948static ssize_t fuse_dev_splice_write(struct pipe_inode_info *pipe,
1949 struct file *out, loff_t *ppos,
1950 size_t len, unsigned int flags)
1951{
1952 unsigned nbuf;
1953 unsigned idx;
1954 struct pipe_buffer *bufs;
1955 struct fuse_copy_state cs;
Miklos Szeredicc080e92015-07-01 16:26:08 +02001956 struct fuse_dev *fud;
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001957 size_t rem;
1958 ssize_t ret;
1959
Miklos Szeredicc080e92015-07-01 16:26:08 +02001960 fud = fuse_get_dev(out);
1961 if (!fud)
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001962 return -EPERM;
1963
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001964 bufs = kmalloc(pipe->buffers * sizeof(struct pipe_buffer), GFP_KERNEL);
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001965 if (!bufs)
1966 return -ENOMEM;
1967
1968 pipe_lock(pipe);
1969 nbuf = 0;
1970 rem = 0;
1971 for (idx = 0; idx < pipe->nrbufs && rem < len; idx++)
1972 rem += pipe->bufs[(pipe->curbuf + idx) & (pipe->buffers - 1)].len;
1973
1974 ret = -EINVAL;
1975 if (rem < len) {
1976 pipe_unlock(pipe);
1977 goto out;
1978 }
1979
1980 rem = len;
1981 while (rem) {
1982 struct pipe_buffer *ibuf;
1983 struct pipe_buffer *obuf;
1984
1985 BUG_ON(nbuf >= pipe->buffers);
1986 BUG_ON(!pipe->nrbufs);
1987 ibuf = &pipe->bufs[pipe->curbuf];
1988 obuf = &bufs[nbuf];
1989
1990 if (rem >= ibuf->len) {
1991 *obuf = *ibuf;
1992 ibuf->ops = NULL;
1993 pipe->curbuf = (pipe->curbuf + 1) & (pipe->buffers - 1);
1994 pipe->nrbufs--;
1995 } else {
1996 ibuf->ops->get(pipe, ibuf);
1997 *obuf = *ibuf;
1998 obuf->flags &= ~PIPE_BUF_FLAG_GIFT;
1999 obuf->len = rem;
2000 ibuf->offset += obuf->len;
2001 ibuf->len -= obuf->len;
2002 }
2003 nbuf++;
2004 rem -= obuf->len;
2005 }
2006 pipe_unlock(pipe);
2007
Miklos Szeredidc008092015-07-01 16:25:58 +02002008 fuse_copy_init(&cs, 0, NULL);
Miklos Szeredidd3bb142010-05-25 15:06:06 +02002009 cs.pipebufs = bufs;
Al Viro6c09e942015-04-03 22:06:08 -04002010 cs.nr_segs = nbuf;
Miklos Szeredidd3bb142010-05-25 15:06:06 +02002011 cs.pipe = pipe;
2012
Miklos Szeredice534fb2010-05-25 15:06:07 +02002013 if (flags & SPLICE_F_MOVE)
2014 cs.move_pages = 1;
2015
Miklos Szeredic36960462015-07-01 16:26:09 +02002016 ret = fuse_dev_do_write(fud, &cs, len);
Miklos Szeredidd3bb142010-05-25 15:06:06 +02002017
2018 for (idx = 0; idx < nbuf; idx++) {
2019 struct pipe_buffer *buf = &bufs[idx];
2020 buf->ops->release(pipe, buf);
2021 }
2022out:
2023 kfree(bufs);
2024 return ret;
2025}
2026
Miklos Szeredi334f4852005-09-09 13:10:27 -07002027static unsigned fuse_dev_poll(struct file *file, poll_table *wait)
2028{
Miklos Szeredi334f4852005-09-09 13:10:27 -07002029 unsigned mask = POLLOUT | POLLWRNORM;
Miklos Szeredif88996a2015-07-01 16:26:01 +02002030 struct fuse_iqueue *fiq;
Miklos Szeredicc080e92015-07-01 16:26:08 +02002031 struct fuse_dev *fud = fuse_get_dev(file);
2032
2033 if (!fud)
Miklos Szeredi7025d9a2006-04-10 22:54:50 -07002034 return POLLERR;
Miklos Szeredi334f4852005-09-09 13:10:27 -07002035
Miklos Szeredicc080e92015-07-01 16:26:08 +02002036 fiq = &fud->fc->iq;
Miklos Szeredif88996a2015-07-01 16:26:01 +02002037 poll_wait(file, &fiq->waitq, wait);
Miklos Szeredi334f4852005-09-09 13:10:27 -07002038
Miklos Szeredi4ce60812015-07-01 16:26:02 +02002039 spin_lock(&fiq->waitq.lock);
Miklos Szeredie16714d2015-07-01 16:26:01 +02002040 if (!fiq->connected)
Miklos Szeredi7025d9a2006-04-10 22:54:50 -07002041 mask = POLLERR;
Miklos Szeredif88996a2015-07-01 16:26:01 +02002042 else if (request_pending(fiq))
Miklos Szeredi7025d9a2006-04-10 22:54:50 -07002043 mask |= POLLIN | POLLRDNORM;
Miklos Szeredi4ce60812015-07-01 16:26:02 +02002044 spin_unlock(&fiq->waitq.lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -07002045
2046 return mask;
2047}
2048
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002049/*
2050 * Abort all requests on the given list (pending or processing)
2051 *
Miklos Szeredid7133112006-04-10 22:54:55 -07002052 * This function releases and reacquires fc->lock
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002053 */
Miklos Szeredi334f4852005-09-09 13:10:27 -07002054static void end_requests(struct fuse_conn *fc, struct list_head *head)
2055{
2056 while (!list_empty(head)) {
2057 struct fuse_req *req;
2058 req = list_entry(head->next, struct fuse_req, list);
Miklos Szeredi334f4852005-09-09 13:10:27 -07002059 req->out.h.error = -ECONNABORTED;
Miklos Szeredi33e14b42015-07-01 16:26:01 +02002060 clear_bit(FR_PENDING, &req->flags);
2061 clear_bit(FR_SENT, &req->flags);
Miklos Szeredif377cb72015-07-01 16:26:04 +02002062 list_del_init(&req->list);
Miklos Szeredi334f4852005-09-09 13:10:27 -07002063 request_end(fc, req);
Miklos Szeredi334f4852005-09-09 13:10:27 -07002064 }
2065}
2066
Bryan Green357ccf22011-03-01 16:43:52 -08002067static void end_polls(struct fuse_conn *fc)
2068{
2069 struct rb_node *p;
2070
2071 p = rb_first(&fc->polled_files);
2072
2073 while (p) {
2074 struct fuse_file *ff;
2075 ff = rb_entry(p, struct fuse_file, polled_node);
2076 wake_up_interruptible_all(&ff->poll_wait);
2077
2078 p = rb_next(p);
2079 }
2080}
2081
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002082/*
2083 * Abort all requests.
2084 *
Miklos Szeredib716d422015-07-01 16:25:59 +02002085 * Emergency exit in case of a malicious or accidental deadlock, or just a hung
2086 * filesystem.
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002087 *
Miklos Szeredib716d422015-07-01 16:25:59 +02002088 * The same effect is usually achievable through killing the filesystem daemon
2089 * and all users of the filesystem. The exception is the combination of an
2090 * asynchronous request and the tricky deadlock (see
2091 * Documentation/filesystems/fuse.txt).
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002092 *
Miklos Szeredib716d422015-07-01 16:25:59 +02002093 * Aborting requests under I/O goes as follows: 1: Separate out unlocked
2094 * requests, they should be finished off immediately. Locked requests will be
2095 * finished after unlock; see unlock_request(). 2: Finish off the unlocked
2096 * requests. It is possible that some request will finish before we can. This
2097 * is OK, the request will in that case be removed from the list before we touch
2098 * it.
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002099 */
2100void fuse_abort_conn(struct fuse_conn *fc)
2101{
Miklos Szeredif88996a2015-07-01 16:26:01 +02002102 struct fuse_iqueue *fiq = &fc->iq;
2103
Miklos Szeredid7133112006-04-10 22:54:55 -07002104 spin_lock(&fc->lock);
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002105 if (fc->connected) {
Miklos Szeredic36960462015-07-01 16:26:09 +02002106 struct fuse_dev *fud;
Miklos Szeredib716d422015-07-01 16:25:59 +02002107 struct fuse_req *req, *next;
Miklos Szeredi41f98272015-07-01 16:25:59 +02002108 LIST_HEAD(to_end1);
2109 LIST_HEAD(to_end2);
Miklos Szeredib716d422015-07-01 16:25:59 +02002110
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002111 fc->connected = 0;
Miklos Szeredi51eb01e2006-06-25 05:48:50 -07002112 fc->blocked = 0;
Miklos Szeredi9759bd512015-01-06 10:45:35 +01002113 fuse_set_initialized(fc);
Miklos Szeredic36960462015-07-01 16:26:09 +02002114 list_for_each_entry(fud, &fc->devices, entry) {
2115 struct fuse_pqueue *fpq = &fud->pq;
2116
2117 spin_lock(&fpq->lock);
2118 fpq->connected = 0;
2119 list_for_each_entry_safe(req, next, &fpq->io, list) {
2120 req->out.h.error = -ECONNABORTED;
2121 spin_lock(&req->waitq.lock);
2122 set_bit(FR_ABORTED, &req->flags);
2123 if (!test_bit(FR_LOCKED, &req->flags)) {
2124 set_bit(FR_PRIVATE, &req->flags);
2125 list_move(&req->list, &to_end1);
2126 }
2127 spin_unlock(&req->waitq.lock);
Miklos Szeredi77cd9d42015-07-01 16:26:06 +02002128 }
Miklos Szeredic36960462015-07-01 16:26:09 +02002129 list_splice_init(&fpq->processing, &to_end2);
2130 spin_unlock(&fpq->lock);
Miklos Szeredib716d422015-07-01 16:25:59 +02002131 }
Miklos Szeredi41f98272015-07-01 16:25:59 +02002132 fc->max_background = UINT_MAX;
2133 flush_bg_queue(fc);
Miklos Szeredi8c911892015-07-01 16:26:02 +02002134
Miklos Szeredi4ce60812015-07-01 16:26:02 +02002135 spin_lock(&fiq->waitq.lock);
Miklos Szeredi8c911892015-07-01 16:26:02 +02002136 fiq->connected = 0;
Miklos Szeredif88996a2015-07-01 16:26:01 +02002137 list_splice_init(&fiq->pending, &to_end2);
Miklos Szeredi8c911892015-07-01 16:26:02 +02002138 while (forget_pending(fiq))
2139 kfree(dequeue_forget(fiq, 1, NULL));
Miklos Szeredi4ce60812015-07-01 16:26:02 +02002140 wake_up_all_locked(&fiq->waitq);
2141 spin_unlock(&fiq->waitq.lock);
Miklos Szeredi8c911892015-07-01 16:26:02 +02002142 kill_fasync(&fiq->fasync, SIGIO, POLL_IN);
Miklos Szerediee314a82015-07-01 16:26:08 +02002143 end_polls(fc);
2144 wake_up_all(&fc->blocked_waitq);
2145 spin_unlock(&fc->lock);
Miklos Szeredi8c911892015-07-01 16:26:02 +02002146
Miklos Szeredi41f98272015-07-01 16:25:59 +02002147 while (!list_empty(&to_end1)) {
2148 req = list_first_entry(&to_end1, struct fuse_req, list);
Miklos Szeredib716d422015-07-01 16:25:59 +02002149 __fuse_get_request(req);
Miklos Szeredif377cb72015-07-01 16:26:04 +02002150 list_del_init(&req->list);
Miklos Szeredib716d422015-07-01 16:25:59 +02002151 request_end(fc, req);
Miklos Szeredib716d422015-07-01 16:25:59 +02002152 }
Miklos Szeredi41f98272015-07-01 16:25:59 +02002153 end_requests(fc, &to_end2);
Miklos Szerediee314a82015-07-01 16:26:08 +02002154 } else {
2155 spin_unlock(&fc->lock);
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002156 }
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002157}
Tejun Heo08cbf542009-04-14 10:54:53 +09002158EXPORT_SYMBOL_GPL(fuse_abort_conn);
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002159
Tejun Heo08cbf542009-04-14 10:54:53 +09002160int fuse_dev_release(struct inode *inode, struct file *file)
Miklos Szeredi334f4852005-09-09 13:10:27 -07002161{
Miklos Szeredicc080e92015-07-01 16:26:08 +02002162 struct fuse_dev *fud = fuse_get_dev(file);
2163
2164 if (fud) {
2165 struct fuse_conn *fc = fud->fc;
Miklos Szeredic36960462015-07-01 16:26:09 +02002166 struct fuse_pqueue *fpq = &fud->pq;
Miklos Szeredicc080e92015-07-01 16:26:08 +02002167
Miklos Szeredic36960462015-07-01 16:26:09 +02002168 WARN_ON(!list_empty(&fpq->io));
2169 end_requests(fc, &fpq->processing);
2170 /* Are we the last open device? */
2171 if (atomic_dec_and_test(&fc->dev_count)) {
2172 WARN_ON(fc->iq.fasync != NULL);
2173 fuse_abort_conn(fc);
2174 }
Miklos Szeredicc080e92015-07-01 16:26:08 +02002175 fuse_dev_free(fud);
Jeff Dike385a17b2006-04-10 22:54:52 -07002176 }
Miklos Szeredi334f4852005-09-09 13:10:27 -07002177 return 0;
2178}
Tejun Heo08cbf542009-04-14 10:54:53 +09002179EXPORT_SYMBOL_GPL(fuse_dev_release);
Miklos Szeredi334f4852005-09-09 13:10:27 -07002180
Jeff Dike385a17b2006-04-10 22:54:52 -07002181static int fuse_dev_fasync(int fd, struct file *file, int on)
2182{
Miklos Szeredicc080e92015-07-01 16:26:08 +02002183 struct fuse_dev *fud = fuse_get_dev(file);
2184
2185 if (!fud)
Miklos Szeredia87046d2006-04-10 22:54:56 -07002186 return -EPERM;
Jeff Dike385a17b2006-04-10 22:54:52 -07002187
2188 /* No locking - fasync_helper does its own locking */
Miklos Szeredicc080e92015-07-01 16:26:08 +02002189 return fasync_helper(fd, file, on, &fud->fc->iq.fasync);
Jeff Dike385a17b2006-04-10 22:54:52 -07002190}
2191
Miklos Szeredi00c570f2015-07-01 16:26:08 +02002192static int fuse_device_clone(struct fuse_conn *fc, struct file *new)
2193{
Miklos Szeredicc080e92015-07-01 16:26:08 +02002194 struct fuse_dev *fud;
2195
Miklos Szeredi00c570f2015-07-01 16:26:08 +02002196 if (new->private_data)
2197 return -EINVAL;
2198
Miklos Szeredicc080e92015-07-01 16:26:08 +02002199 fud = fuse_dev_alloc(fc);
2200 if (!fud)
2201 return -ENOMEM;
2202
2203 new->private_data = fud;
Miklos Szeredic36960462015-07-01 16:26:09 +02002204 atomic_inc(&fc->dev_count);
Miklos Szeredi00c570f2015-07-01 16:26:08 +02002205
2206 return 0;
2207}
2208
2209static long fuse_dev_ioctl(struct file *file, unsigned int cmd,
2210 unsigned long arg)
2211{
2212 int err = -ENOTTY;
2213
2214 if (cmd == FUSE_DEV_IOC_CLONE) {
2215 int oldfd;
2216
2217 err = -EFAULT;
2218 if (!get_user(oldfd, (__u32 __user *) arg)) {
2219 struct file *old = fget(oldfd);
2220
2221 err = -EINVAL;
2222 if (old) {
Jann Horn8ed1f0e2015-08-16 20:27:01 +02002223 struct fuse_dev *fud = NULL;
2224
2225 /*
2226 * Check against file->f_op because CUSE
2227 * uses the same ioctl handler.
2228 */
2229 if (old->f_op == file->f_op &&
2230 old->f_cred->user_ns == file->f_cred->user_ns)
2231 fud = fuse_get_dev(old);
Miklos Szeredi00c570f2015-07-01 16:26:08 +02002232
Miklos Szeredicc080e92015-07-01 16:26:08 +02002233 if (fud) {
Miklos Szeredi00c570f2015-07-01 16:26:08 +02002234 mutex_lock(&fuse_mutex);
Miklos Szeredicc080e92015-07-01 16:26:08 +02002235 err = fuse_device_clone(fud->fc, file);
Miklos Szeredi00c570f2015-07-01 16:26:08 +02002236 mutex_unlock(&fuse_mutex);
2237 }
2238 fput(old);
2239 }
2240 }
2241 }
2242 return err;
2243}
2244
Arjan van de Ven4b6f5d22006-03-28 01:56:42 -08002245const struct file_operations fuse_dev_operations = {
Miklos Szeredi334f4852005-09-09 13:10:27 -07002246 .owner = THIS_MODULE,
Tom Van Braeckel94e4fe22015-01-12 05:22:16 +01002247 .open = fuse_dev_open,
Miklos Szeredi334f4852005-09-09 13:10:27 -07002248 .llseek = no_llseek,
Al Virofbdbacc2015-04-03 21:53:39 -04002249 .read_iter = fuse_dev_read,
Miklos Szeredic3021622010-05-25 15:06:07 +02002250 .splice_read = fuse_dev_splice_read,
Al Virofbdbacc2015-04-03 21:53:39 -04002251 .write_iter = fuse_dev_write,
Miklos Szeredidd3bb142010-05-25 15:06:06 +02002252 .splice_write = fuse_dev_splice_write,
Miklos Szeredi334f4852005-09-09 13:10:27 -07002253 .poll = fuse_dev_poll,
2254 .release = fuse_dev_release,
Jeff Dike385a17b2006-04-10 22:54:52 -07002255 .fasync = fuse_dev_fasync,
Miklos Szeredi00c570f2015-07-01 16:26:08 +02002256 .unlocked_ioctl = fuse_dev_ioctl,
2257 .compat_ioctl = fuse_dev_ioctl,
Miklos Szeredi334f4852005-09-09 13:10:27 -07002258};
Tejun Heo08cbf542009-04-14 10:54:53 +09002259EXPORT_SYMBOL_GPL(fuse_dev_operations);
Miklos Szeredi334f4852005-09-09 13:10:27 -07002260
2261static struct miscdevice fuse_miscdevice = {
2262 .minor = FUSE_MINOR,
2263 .name = "fuse",
2264 .fops = &fuse_dev_operations,
2265};
2266
2267int __init fuse_dev_init(void)
2268{
2269 int err = -ENOMEM;
2270 fuse_req_cachep = kmem_cache_create("fuse_request",
2271 sizeof(struct fuse_req),
Paul Mundt20c2df82007-07-20 10:11:58 +09002272 0, 0, NULL);
Miklos Szeredi334f4852005-09-09 13:10:27 -07002273 if (!fuse_req_cachep)
2274 goto out;
2275
2276 err = misc_register(&fuse_miscdevice);
2277 if (err)
2278 goto out_cache_clean;
2279
2280 return 0;
2281
2282 out_cache_clean:
2283 kmem_cache_destroy(fuse_req_cachep);
2284 out:
2285 return err;
2286}
2287
2288void fuse_dev_cleanup(void)
2289{
2290 misc_deregister(&fuse_miscdevice);
2291 kmem_cache_destroy(fuse_req_cachep);
2292}