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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) {
Miklos Szeredifba597d2016-09-27 10:45:12 +0200731 err = pipe_buf_confirm(cs->pipe, buf);
Miklos Szeredic3021622010-05-25 15:06:07 +0200732 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 iov_iter_advance(cs->iter, err);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700771 }
Miklos Szeredi334f4852005-09-09 13:10:27 -0700772
Miklos Szeredidc008092015-07-01 16:25:58 +0200773 return lock_request(cs->req);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700774}
775
776/* Do as much copy to/from userspace buffer as we can */
Miklos Szeredi8bfc0162006-01-16 22:14:28 -0800777static int fuse_copy_do(struct fuse_copy_state *cs, void **val, unsigned *size)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700778{
779 unsigned ncpy = min(*size, cs->len);
780 if (val) {
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200781 void *pgaddr = kmap_atomic(cs->pg);
782 void *buf = pgaddr + cs->offset;
783
Miklos Szeredi334f4852005-09-09 13:10:27 -0700784 if (cs->write)
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200785 memcpy(buf, *val, ncpy);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700786 else
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200787 memcpy(*val, buf, ncpy);
788
789 kunmap_atomic(pgaddr);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700790 *val += ncpy;
791 }
792 *size -= ncpy;
793 cs->len -= ncpy;
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200794 cs->offset += ncpy;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700795 return ncpy;
796}
797
Miklos Szeredice534fb2010-05-25 15:06:07 +0200798static int fuse_check_page(struct page *page)
799{
800 if (page_mapcount(page) ||
801 page->mapping != NULL ||
802 page_count(page) != 1 ||
803 (page->flags & PAGE_FLAGS_CHECK_AT_PREP &
804 ~(1 << PG_locked |
805 1 << PG_referenced |
806 1 << PG_uptodate |
807 1 << PG_lru |
808 1 << PG_active |
809 1 << PG_reclaim))) {
810 printk(KERN_WARNING "fuse: trying to steal weird page\n");
811 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);
812 return 1;
813 }
814 return 0;
815}
816
817static int fuse_try_move_page(struct fuse_copy_state *cs, struct page **pagep)
818{
819 int err;
820 struct page *oldpage = *pagep;
821 struct page *newpage;
822 struct pipe_buffer *buf = cs->pipebufs;
Miklos Szeredice534fb2010-05-25 15:06:07 +0200823
Miklos Szeredidc008092015-07-01 16:25:58 +0200824 err = unlock_request(cs->req);
Miklos Szeredi0d8e84b2015-07-01 16:25:58 +0200825 if (err)
826 return err;
827
Miklos Szeredice534fb2010-05-25 15:06:07 +0200828 fuse_copy_finish(cs);
829
Miklos Szeredifba597d2016-09-27 10:45:12 +0200830 err = pipe_buf_confirm(cs->pipe, buf);
Miklos Szeredice534fb2010-05-25 15:06:07 +0200831 if (err)
832 return err;
833
834 BUG_ON(!cs->nr_segs);
835 cs->currbuf = buf;
836 cs->len = buf->len;
837 cs->pipebufs++;
838 cs->nr_segs--;
839
840 if (cs->len != PAGE_SIZE)
841 goto out_fallback;
842
Miklos Szeredica76f5b2016-09-27 10:45:12 +0200843 if (pipe_buf_steal(cs->pipe, buf) != 0)
Miklos Szeredice534fb2010-05-25 15:06:07 +0200844 goto out_fallback;
845
846 newpage = buf->page;
847
Miklos Szerediaa991b32015-02-26 11:45:47 +0100848 if (!PageUptodate(newpage))
849 SetPageUptodate(newpage);
Miklos Szeredice534fb2010-05-25 15:06:07 +0200850
851 ClearPageMappedToDisk(newpage);
852
853 if (fuse_check_page(newpage) != 0)
854 goto out_fallback_unlock;
855
Miklos Szeredice534fb2010-05-25 15:06:07 +0200856 /*
857 * This is a new and locked page, it shouldn't be mapped or
858 * have any special flags on it
859 */
860 if (WARN_ON(page_mapped(oldpage)))
861 goto out_fallback_unlock;
862 if (WARN_ON(page_has_private(oldpage)))
863 goto out_fallback_unlock;
864 if (WARN_ON(PageDirty(oldpage) || PageWriteback(oldpage)))
865 goto out_fallback_unlock;
866 if (WARN_ON(PageMlocked(oldpage)))
867 goto out_fallback_unlock;
868
Miklos Szeredief6a3c62011-03-22 16:30:52 -0700869 err = replace_page_cache_page(oldpage, newpage, GFP_KERNEL);
Miklos Szeredice534fb2010-05-25 15:06:07 +0200870 if (err) {
Miklos Szeredief6a3c62011-03-22 16:30:52 -0700871 unlock_page(newpage);
872 return err;
Miklos Szeredice534fb2010-05-25 15:06:07 +0200873 }
Miklos Szeredief6a3c62011-03-22 16:30:52 -0700874
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +0300875 get_page(newpage);
Miklos Szeredice534fb2010-05-25 15:06:07 +0200876
877 if (!(buf->flags & PIPE_BUF_FLAG_LRU))
878 lru_cache_add_file(newpage);
879
880 err = 0;
Miklos Szeredidc008092015-07-01 16:25:58 +0200881 spin_lock(&cs->req->waitq.lock);
Miklos Szeredi825d6d32015-07-01 16:25:58 +0200882 if (test_bit(FR_ABORTED, &cs->req->flags))
Miklos Szeredice534fb2010-05-25 15:06:07 +0200883 err = -ENOENT;
884 else
885 *pagep = newpage;
Miklos Szeredidc008092015-07-01 16:25:58 +0200886 spin_unlock(&cs->req->waitq.lock);
Miklos Szeredice534fb2010-05-25 15:06:07 +0200887
888 if (err) {
889 unlock_page(newpage);
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +0300890 put_page(newpage);
Miklos Szeredice534fb2010-05-25 15:06:07 +0200891 return err;
892 }
893
894 unlock_page(oldpage);
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +0300895 put_page(oldpage);
Miklos Szeredice534fb2010-05-25 15:06:07 +0200896 cs->len = 0;
897
898 return 0;
899
900out_fallback_unlock:
901 unlock_page(newpage);
902out_fallback:
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200903 cs->pg = buf->page;
904 cs->offset = buf->offset;
Miklos Szeredice534fb2010-05-25 15:06:07 +0200905
Miklos Szeredidc008092015-07-01 16:25:58 +0200906 err = lock_request(cs->req);
Miklos Szeredice534fb2010-05-25 15:06:07 +0200907 if (err)
908 return err;
909
910 return 1;
911}
912
Miklos Szeredic3021622010-05-25 15:06:07 +0200913static int fuse_ref_page(struct fuse_copy_state *cs, struct page *page,
914 unsigned offset, unsigned count)
915{
916 struct pipe_buffer *buf;
Miklos Szeredi0d8e84b2015-07-01 16:25:58 +0200917 int err;
Miklos Szeredic3021622010-05-25 15:06:07 +0200918
919 if (cs->nr_segs == cs->pipe->buffers)
920 return -EIO;
921
Miklos Szeredidc008092015-07-01 16:25:58 +0200922 err = unlock_request(cs->req);
Miklos Szeredi0d8e84b2015-07-01 16:25:58 +0200923 if (err)
924 return err;
925
Miklos Szeredic3021622010-05-25 15:06:07 +0200926 fuse_copy_finish(cs);
927
928 buf = cs->pipebufs;
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +0300929 get_page(page);
Miklos Szeredic3021622010-05-25 15:06:07 +0200930 buf->page = page;
931 buf->offset = offset;
932 buf->len = count;
933
934 cs->pipebufs++;
935 cs->nr_segs++;
936 cs->len = 0;
937
938 return 0;
939}
940
Miklos Szeredi334f4852005-09-09 13:10:27 -0700941/*
942 * Copy a page in the request to/from the userspace buffer. Must be
943 * done atomically
944 */
Miklos Szeredice534fb2010-05-25 15:06:07 +0200945static int fuse_copy_page(struct fuse_copy_state *cs, struct page **pagep,
Miklos Szeredi8bfc0162006-01-16 22:14:28 -0800946 unsigned offset, unsigned count, int zeroing)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700947{
Miklos Szeredice534fb2010-05-25 15:06:07 +0200948 int err;
949 struct page *page = *pagep;
950
Miklos Szeredib6777c42010-10-26 14:22:27 -0700951 if (page && zeroing && count < PAGE_SIZE)
952 clear_highpage(page);
953
Miklos Szeredi334f4852005-09-09 13:10:27 -0700954 while (count) {
Miklos Szeredic3021622010-05-25 15:06:07 +0200955 if (cs->write && cs->pipebufs && page) {
956 return fuse_ref_page(cs, page, offset, count);
957 } else if (!cs->len) {
Miklos Szeredice534fb2010-05-25 15:06:07 +0200958 if (cs->move_pages && page &&
959 offset == 0 && count == PAGE_SIZE) {
960 err = fuse_try_move_page(cs, pagep);
961 if (err <= 0)
962 return err;
963 } else {
964 err = fuse_copy_fill(cs);
965 if (err)
966 return err;
967 }
Miklos Szeredi1729a162008-11-26 12:03:54 +0100968 }
Miklos Szeredi334f4852005-09-09 13:10:27 -0700969 if (page) {
Cong Wang2408f6e2011-11-25 23:14:30 +0800970 void *mapaddr = kmap_atomic(page);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700971 void *buf = mapaddr + offset;
972 offset += fuse_copy_do(cs, &buf, &count);
Cong Wang2408f6e2011-11-25 23:14:30 +0800973 kunmap_atomic(mapaddr);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700974 } else
975 offset += fuse_copy_do(cs, NULL, &count);
976 }
977 if (page && !cs->write)
978 flush_dcache_page(page);
979 return 0;
980}
981
982/* Copy pages in the request to/from userspace buffer */
983static int fuse_copy_pages(struct fuse_copy_state *cs, unsigned nbytes,
984 int zeroing)
985{
986 unsigned i;
987 struct fuse_req *req = cs->req;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700988
989 for (i = 0; i < req->num_pages && (nbytes || zeroing); i++) {
Miklos Szeredice534fb2010-05-25 15:06:07 +0200990 int err;
Maxim Patlasov85f40ae2012-10-26 19:49:33 +0400991 unsigned offset = req->page_descs[i].offset;
992 unsigned count = min(nbytes, req->page_descs[i].length);
Miklos Szeredice534fb2010-05-25 15:06:07 +0200993
994 err = fuse_copy_page(cs, &req->pages[i], offset, count,
995 zeroing);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700996 if (err)
997 return err;
998
999 nbytes -= count;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001000 }
1001 return 0;
1002}
1003
1004/* Copy a single argument in the request to/from userspace buffer */
1005static int fuse_copy_one(struct fuse_copy_state *cs, void *val, unsigned size)
1006{
1007 while (size) {
Miklos Szeredi1729a162008-11-26 12:03:54 +01001008 if (!cs->len) {
1009 int err = fuse_copy_fill(cs);
1010 if (err)
1011 return err;
1012 }
Miklos Szeredi334f4852005-09-09 13:10:27 -07001013 fuse_copy_do(cs, &val, &size);
1014 }
1015 return 0;
1016}
1017
1018/* Copy request arguments to/from userspace buffer */
1019static int fuse_copy_args(struct fuse_copy_state *cs, unsigned numargs,
1020 unsigned argpages, struct fuse_arg *args,
1021 int zeroing)
1022{
1023 int err = 0;
1024 unsigned i;
1025
1026 for (i = 0; !err && i < numargs; i++) {
1027 struct fuse_arg *arg = &args[i];
1028 if (i == numargs - 1 && argpages)
1029 err = fuse_copy_pages(cs, arg->size, zeroing);
1030 else
1031 err = fuse_copy_one(cs, arg->value, arg->size);
1032 }
1033 return err;
1034}
1035
Miklos Szeredif88996a2015-07-01 16:26:01 +02001036static int forget_pending(struct fuse_iqueue *fiq)
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001037{
Miklos Szeredif88996a2015-07-01 16:26:01 +02001038 return fiq->forget_list_head.next != NULL;
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001039}
1040
Miklos Szeredif88996a2015-07-01 16:26:01 +02001041static int request_pending(struct fuse_iqueue *fiq)
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001042{
Miklos Szeredif88996a2015-07-01 16:26:01 +02001043 return !list_empty(&fiq->pending) || !list_empty(&fiq->interrupts) ||
1044 forget_pending(fiq);
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001045}
1046
Miklos Szeredi334f4852005-09-09 13:10:27 -07001047/*
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001048 * Transfer an interrupt request to userspace
1049 *
1050 * Unlike other requests this is assembled on demand, without a need
1051 * to allocate a separate fuse_req structure.
1052 *
Miklos Szeredifd22d622015-07-01 16:26:03 +02001053 * Called with fiq->waitq.lock held, releases it
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001054 */
Miklos Szeredifd22d622015-07-01 16:26:03 +02001055static int fuse_read_interrupt(struct fuse_iqueue *fiq,
1056 struct fuse_copy_state *cs,
Miklos Szeredic3021622010-05-25 15:06:07 +02001057 size_t nbytes, struct fuse_req *req)
Miklos Szeredifd22d622015-07-01 16:26:03 +02001058__releases(fiq->waitq.lock)
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001059{
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001060 struct fuse_in_header ih;
1061 struct fuse_interrupt_in arg;
1062 unsigned reqsize = sizeof(ih) + sizeof(arg);
1063 int err;
1064
1065 list_del_init(&req->intr_entry);
Miklos Szeredi4ce60812015-07-01 16:26:02 +02001066 req->intr_unique = fuse_get_unique(fiq);
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001067 memset(&ih, 0, sizeof(ih));
1068 memset(&arg, 0, sizeof(arg));
1069 ih.len = reqsize;
1070 ih.opcode = FUSE_INTERRUPT;
1071 ih.unique = req->intr_unique;
1072 arg.unique = req->in.h.unique;
1073
Miklos Szeredi4ce60812015-07-01 16:26:02 +02001074 spin_unlock(&fiq->waitq.lock);
Miklos Szeredic3021622010-05-25 15:06:07 +02001075 if (nbytes < reqsize)
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001076 return -EINVAL;
1077
Miklos Szeredic3021622010-05-25 15:06:07 +02001078 err = fuse_copy_one(cs, &ih, sizeof(ih));
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001079 if (!err)
Miklos Szeredic3021622010-05-25 15:06:07 +02001080 err = fuse_copy_one(cs, &arg, sizeof(arg));
1081 fuse_copy_finish(cs);
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001082
1083 return err ? err : reqsize;
1084}
1085
Miklos Szeredif88996a2015-07-01 16:26:01 +02001086static struct fuse_forget_link *dequeue_forget(struct fuse_iqueue *fiq,
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001087 unsigned max,
1088 unsigned *countp)
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001089{
Miklos Szeredif88996a2015-07-01 16:26:01 +02001090 struct fuse_forget_link *head = fiq->forget_list_head.next;
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001091 struct fuse_forget_link **newhead = &head;
1092 unsigned count;
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001093
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001094 for (count = 0; *newhead != NULL && count < max; count++)
1095 newhead = &(*newhead)->next;
1096
Miklos Szeredif88996a2015-07-01 16:26:01 +02001097 fiq->forget_list_head.next = *newhead;
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001098 *newhead = NULL;
Miklos Szeredif88996a2015-07-01 16:26:01 +02001099 if (fiq->forget_list_head.next == NULL)
1100 fiq->forget_list_tail = &fiq->forget_list_head;
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001101
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001102 if (countp != NULL)
1103 *countp = count;
1104
1105 return head;
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001106}
1107
Miklos Szeredifd22d622015-07-01 16:26:03 +02001108static int fuse_read_single_forget(struct fuse_iqueue *fiq,
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001109 struct fuse_copy_state *cs,
1110 size_t nbytes)
Miklos Szeredifd22d622015-07-01 16:26:03 +02001111__releases(fiq->waitq.lock)
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001112{
1113 int err;
Miklos Szeredif88996a2015-07-01 16:26:01 +02001114 struct fuse_forget_link *forget = dequeue_forget(fiq, 1, NULL);
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001115 struct fuse_forget_in arg = {
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001116 .nlookup = forget->forget_one.nlookup,
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001117 };
1118 struct fuse_in_header ih = {
1119 .opcode = FUSE_FORGET,
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001120 .nodeid = forget->forget_one.nodeid,
Miklos Szeredif88996a2015-07-01 16:26:01 +02001121 .unique = fuse_get_unique(fiq),
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001122 .len = sizeof(ih) + sizeof(arg),
1123 };
1124
Miklos Szeredi4ce60812015-07-01 16:26:02 +02001125 spin_unlock(&fiq->waitq.lock);
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001126 kfree(forget);
1127 if (nbytes < ih.len)
1128 return -EINVAL;
1129
1130 err = fuse_copy_one(cs, &ih, sizeof(ih));
1131 if (!err)
1132 err = fuse_copy_one(cs, &arg, sizeof(arg));
1133 fuse_copy_finish(cs);
1134
1135 if (err)
1136 return err;
1137
1138 return ih.len;
1139}
1140
Miklos Szeredifd22d622015-07-01 16:26:03 +02001141static int fuse_read_batch_forget(struct fuse_iqueue *fiq,
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001142 struct fuse_copy_state *cs, size_t nbytes)
Miklos Szeredifd22d622015-07-01 16:26:03 +02001143__releases(fiq->waitq.lock)
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001144{
1145 int err;
1146 unsigned max_forgets;
1147 unsigned count;
1148 struct fuse_forget_link *head;
1149 struct fuse_batch_forget_in arg = { .count = 0 };
1150 struct fuse_in_header ih = {
1151 .opcode = FUSE_BATCH_FORGET,
Miklos Szeredif88996a2015-07-01 16:26:01 +02001152 .unique = fuse_get_unique(fiq),
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001153 .len = sizeof(ih) + sizeof(arg),
1154 };
1155
1156 if (nbytes < ih.len) {
Miklos Szeredi4ce60812015-07-01 16:26:02 +02001157 spin_unlock(&fiq->waitq.lock);
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001158 return -EINVAL;
1159 }
1160
1161 max_forgets = (nbytes - ih.len) / sizeof(struct fuse_forget_one);
Miklos Szeredif88996a2015-07-01 16:26:01 +02001162 head = dequeue_forget(fiq, max_forgets, &count);
Miklos Szeredi4ce60812015-07-01 16:26:02 +02001163 spin_unlock(&fiq->waitq.lock);
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001164
1165 arg.count = count;
1166 ih.len += count * sizeof(struct fuse_forget_one);
1167 err = fuse_copy_one(cs, &ih, sizeof(ih));
1168 if (!err)
1169 err = fuse_copy_one(cs, &arg, sizeof(arg));
1170
1171 while (head) {
1172 struct fuse_forget_link *forget = head;
1173
1174 if (!err) {
1175 err = fuse_copy_one(cs, &forget->forget_one,
1176 sizeof(forget->forget_one));
1177 }
1178 head = forget->next;
1179 kfree(forget);
1180 }
1181
1182 fuse_copy_finish(cs);
1183
1184 if (err)
1185 return err;
1186
1187 return ih.len;
1188}
1189
Miklos Szeredifd22d622015-07-01 16:26:03 +02001190static int fuse_read_forget(struct fuse_conn *fc, struct fuse_iqueue *fiq,
1191 struct fuse_copy_state *cs,
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001192 size_t nbytes)
Miklos Szeredifd22d622015-07-01 16:26:03 +02001193__releases(fiq->waitq.lock)
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001194{
Miklos Szeredif88996a2015-07-01 16:26:01 +02001195 if (fc->minor < 16 || fiq->forget_list_head.next->next == NULL)
Miklos Szeredifd22d622015-07-01 16:26:03 +02001196 return fuse_read_single_forget(fiq, cs, nbytes);
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001197 else
Miklos Szeredifd22d622015-07-01 16:26:03 +02001198 return fuse_read_batch_forget(fiq, cs, nbytes);
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001199}
1200
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001201/*
Miklos Szeredi334f4852005-09-09 13:10:27 -07001202 * Read a single request into the userspace filesystem's buffer. This
1203 * function waits until a request is available, then removes it from
1204 * the pending list and copies request data to userspace buffer. If
Miklos Szeredif9a28422006-06-25 05:48:53 -07001205 * no reply is needed (FORGET) or request has been aborted or there
1206 * was an error during the copying then it's finished by calling
Miklos Szeredi334f4852005-09-09 13:10:27 -07001207 * request_end(). Otherwise add it to the processing list, and set
1208 * the 'sent' flag.
1209 */
Miklos Szeredic36960462015-07-01 16:26:09 +02001210static ssize_t fuse_dev_do_read(struct fuse_dev *fud, struct file *file,
Miklos Szeredic3021622010-05-25 15:06:07 +02001211 struct fuse_copy_state *cs, size_t nbytes)
Miklos Szeredi334f4852005-09-09 13:10:27 -07001212{
Miklos Szeredi82cbdcd2015-07-01 16:26:05 +02001213 ssize_t err;
Miklos Szeredic36960462015-07-01 16:26:09 +02001214 struct fuse_conn *fc = fud->fc;
Miklos Szeredif88996a2015-07-01 16:26:01 +02001215 struct fuse_iqueue *fiq = &fc->iq;
Miklos Szeredic36960462015-07-01 16:26:09 +02001216 struct fuse_pqueue *fpq = &fud->pq;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001217 struct fuse_req *req;
1218 struct fuse_in *in;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001219 unsigned reqsize;
1220
Miklos Szeredi1d3d7522006-01-06 00:19:40 -08001221 restart:
Miklos Szeredi4ce60812015-07-01 16:26:02 +02001222 spin_lock(&fiq->waitq.lock);
Jeff Dikee5ac1d12006-04-10 22:54:53 -07001223 err = -EAGAIN;
Miklos Szeredie16714d2015-07-01 16:26:01 +02001224 if ((file->f_flags & O_NONBLOCK) && fiq->connected &&
Miklos Szeredif88996a2015-07-01 16:26:01 +02001225 !request_pending(fiq))
Jeff Dikee5ac1d12006-04-10 22:54:53 -07001226 goto err_unlock;
1227
Miklos Szeredi52509212015-07-01 16:26:03 +02001228 err = wait_event_interruptible_exclusive_locked(fiq->waitq,
1229 !fiq->connected || request_pending(fiq));
1230 if (err)
1231 goto err_unlock;
1232
Miklos Szeredi334f4852005-09-09 13:10:27 -07001233 err = -ENODEV;
Miklos Szeredie16714d2015-07-01 16:26:01 +02001234 if (!fiq->connected)
Miklos Szeredi334f4852005-09-09 13:10:27 -07001235 goto err_unlock;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001236
Miklos Szeredif88996a2015-07-01 16:26:01 +02001237 if (!list_empty(&fiq->interrupts)) {
1238 req = list_entry(fiq->interrupts.next, struct fuse_req,
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001239 intr_entry);
Miklos Szeredifd22d622015-07-01 16:26:03 +02001240 return fuse_read_interrupt(fiq, cs, nbytes, req);
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001241 }
1242
Miklos Szeredif88996a2015-07-01 16:26:01 +02001243 if (forget_pending(fiq)) {
1244 if (list_empty(&fiq->pending) || fiq->forget_batch-- > 0)
Miklos Szeredifd22d622015-07-01 16:26:03 +02001245 return fuse_read_forget(fc, fiq, cs, nbytes);
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001246
Miklos Szeredif88996a2015-07-01 16:26:01 +02001247 if (fiq->forget_batch <= -8)
1248 fiq->forget_batch = 16;
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001249 }
1250
Miklos Szeredif88996a2015-07-01 16:26:01 +02001251 req = list_entry(fiq->pending.next, struct fuse_req, list);
Miklos Szeredi33e14b42015-07-01 16:26:01 +02001252 clear_bit(FR_PENDING, &req->flags);
Miklos Szeredief759252015-07-01 16:26:02 +02001253 list_del_init(&req->list);
Miklos Szeredi4ce60812015-07-01 16:26:02 +02001254 spin_unlock(&fiq->waitq.lock);
1255
Miklos Szeredi334f4852005-09-09 13:10:27 -07001256 in = &req->in;
Miklos Szeredi1d3d7522006-01-06 00:19:40 -08001257 reqsize = in->h.len;
1258 /* If request is too large, reply with an error and restart the read */
Miklos Szeredic3021622010-05-25 15:06:07 +02001259 if (nbytes < reqsize) {
Miklos Szeredi1d3d7522006-01-06 00:19:40 -08001260 req->out.h.error = -EIO;
1261 /* SETXATTR is special, since it may contain too large data */
1262 if (in->h.opcode == FUSE_SETXATTR)
1263 req->out.h.error = -E2BIG;
1264 request_end(fc, req);
1265 goto restart;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001266 }
Miklos Szeredi45a91cb2015-07-01 16:26:06 +02001267 spin_lock(&fpq->lock);
Miklos Szeredi82cbdcd2015-07-01 16:26:05 +02001268 list_add(&req->list, &fpq->io);
Miklos Szeredi45a91cb2015-07-01 16:26:06 +02001269 spin_unlock(&fpq->lock);
Miklos Szeredic3021622010-05-25 15:06:07 +02001270 cs->req = req;
1271 err = fuse_copy_one(cs, &in->h, sizeof(in->h));
Miklos Szeredi1d3d7522006-01-06 00:19:40 -08001272 if (!err)
Miklos Szeredic3021622010-05-25 15:06:07 +02001273 err = fuse_copy_args(cs, in->numargs, in->argpages,
Miklos Szeredi1d3d7522006-01-06 00:19:40 -08001274 (struct fuse_arg *) in->args, 0);
Miklos Szeredic3021622010-05-25 15:06:07 +02001275 fuse_copy_finish(cs);
Miklos Szeredi45a91cb2015-07-01 16:26:06 +02001276 spin_lock(&fpq->lock);
Miklos Szeredi825d6d32015-07-01 16:25:58 +02001277 clear_bit(FR_LOCKED, &req->flags);
Miklos Szeredie96edd92015-07-01 16:26:04 +02001278 if (!fpq->connected) {
Miklos Szeredi82cbdcd2015-07-01 16:26:05 +02001279 err = -ENODEV;
1280 goto out_end;
Miklos Szeredic9c9d7d2007-10-16 23:31:05 -07001281 }
Miklos Szeredi334f4852005-09-09 13:10:27 -07001282 if (err) {
Miklos Szeredic9c9d7d2007-10-16 23:31:05 -07001283 req->out.h.error = -EIO;
Miklos Szeredi82cbdcd2015-07-01 16:26:05 +02001284 goto out_end;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001285 }
Miklos Szeredi825d6d32015-07-01 16:25:58 +02001286 if (!test_bit(FR_ISREPLY, &req->flags)) {
Miklos Szeredi82cbdcd2015-07-01 16:26:05 +02001287 err = reqsize;
1288 goto out_end;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001289 }
Miklos Szeredi82cbdcd2015-07-01 16:26:05 +02001290 list_move_tail(&req->list, &fpq->processing);
Miklos Szeredi45a91cb2015-07-01 16:26:06 +02001291 spin_unlock(&fpq->lock);
Miklos Szeredi82cbdcd2015-07-01 16:26:05 +02001292 set_bit(FR_SENT, &req->flags);
1293 /* matches barrier in request_wait_answer() */
1294 smp_mb__after_atomic();
1295 if (test_bit(FR_INTERRUPTED, &req->flags))
1296 queue_interrupt(fiq, req);
Miklos Szeredi82cbdcd2015-07-01 16:26:05 +02001297
Miklos Szeredi334f4852005-09-09 13:10:27 -07001298 return reqsize;
1299
Miklos Szeredi82cbdcd2015-07-01 16:26:05 +02001300out_end:
Miklos Szeredi77cd9d42015-07-01 16:26:06 +02001301 if (!test_bit(FR_PRIVATE, &req->flags))
1302 list_del_init(&req->list);
Miklos Szeredi45a91cb2015-07-01 16:26:06 +02001303 spin_unlock(&fpq->lock);
Miklos Szeredi82cbdcd2015-07-01 16:26:05 +02001304 request_end(fc, req);
1305 return err;
1306
Miklos Szeredi334f4852005-09-09 13:10:27 -07001307 err_unlock:
Miklos Szeredi4ce60812015-07-01 16:26:02 +02001308 spin_unlock(&fiq->waitq.lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001309 return err;
1310}
1311
Tom Van Braeckel94e4fe22015-01-12 05:22:16 +01001312static int fuse_dev_open(struct inode *inode, struct file *file)
1313{
1314 /*
1315 * The fuse device's file's private_data is used to hold
1316 * the fuse_conn(ection) when it is mounted, and is used to
1317 * keep track of whether the file has been mounted already.
1318 */
1319 file->private_data = NULL;
1320 return 0;
1321}
1322
Al Virofbdbacc2015-04-03 21:53:39 -04001323static ssize_t fuse_dev_read(struct kiocb *iocb, struct iov_iter *to)
Miklos Szeredic3021622010-05-25 15:06:07 +02001324{
1325 struct fuse_copy_state cs;
1326 struct file *file = iocb->ki_filp;
Miklos Szeredicc080e92015-07-01 16:26:08 +02001327 struct fuse_dev *fud = fuse_get_dev(file);
1328
1329 if (!fud)
Miklos Szeredic3021622010-05-25 15:06:07 +02001330 return -EPERM;
1331
Al Virofbdbacc2015-04-03 21:53:39 -04001332 if (!iter_is_iovec(to))
1333 return -EINVAL;
Miklos Szeredic3021622010-05-25 15:06:07 +02001334
Miklos Szeredidc008092015-07-01 16:25:58 +02001335 fuse_copy_init(&cs, 1, to);
Al Virofbdbacc2015-04-03 21:53:39 -04001336
Miklos Szeredic36960462015-07-01 16:26:09 +02001337 return fuse_dev_do_read(fud, file, &cs, iov_iter_count(to));
Miklos Szeredic3021622010-05-25 15:06:07 +02001338}
1339
Miklos Szeredic3021622010-05-25 15:06:07 +02001340static ssize_t fuse_dev_splice_read(struct file *in, loff_t *ppos,
1341 struct pipe_inode_info *pipe,
1342 size_t len, unsigned int flags)
1343{
Al Virod82718e2016-09-17 22:56:25 -04001344 int total, ret;
Miklos Szeredic3021622010-05-25 15:06:07 +02001345 int page_nr = 0;
Miklos Szeredic3021622010-05-25 15:06:07 +02001346 struct pipe_buffer *bufs;
1347 struct fuse_copy_state cs;
Miklos Szeredicc080e92015-07-01 16:26:08 +02001348 struct fuse_dev *fud = fuse_get_dev(in);
1349
1350 if (!fud)
Miklos Szeredic3021622010-05-25 15:06:07 +02001351 return -EPERM;
1352
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001353 bufs = kmalloc(pipe->buffers * sizeof(struct pipe_buffer), GFP_KERNEL);
Miklos Szeredic3021622010-05-25 15:06:07 +02001354 if (!bufs)
1355 return -ENOMEM;
1356
Miklos Szeredidc008092015-07-01 16:25:58 +02001357 fuse_copy_init(&cs, 1, NULL);
Miklos Szeredic3021622010-05-25 15:06:07 +02001358 cs.pipebufs = bufs;
1359 cs.pipe = pipe;
Miklos Szeredic36960462015-07-01 16:26:09 +02001360 ret = fuse_dev_do_read(fud, in, &cs, len);
Miklos Szeredic3021622010-05-25 15:06:07 +02001361 if (ret < 0)
1362 goto out;
1363
Miklos Szeredic3021622010-05-25 15:06:07 +02001364 if (pipe->nrbufs + cs.nr_segs > pipe->buffers) {
1365 ret = -EIO;
Al Virod82718e2016-09-17 22:56:25 -04001366 goto out;
Miklos Szeredic3021622010-05-25 15:06:07 +02001367 }
1368
Al Virod82718e2016-09-17 22:56:25 -04001369 for (ret = total = 0; page_nr < cs.nr_segs; total += ret) {
Miklos Szeredi28a625c2014-01-22 19:36:57 +01001370 /*
1371 * Need to be careful about this. Having buf->ops in module
1372 * code can Oops if the buffer persists after module unload.
1373 */
Al Virod82718e2016-09-17 22:56:25 -04001374 bufs[page_nr].ops = &nosteal_pipe_buf_ops;
1375 ret = add_to_pipe(pipe, &bufs[page_nr++]);
1376 if (unlikely(ret < 0))
1377 break;
Miklos Szeredic3021622010-05-25 15:06:07 +02001378 }
Al Virod82718e2016-09-17 22:56:25 -04001379 if (total)
1380 ret = total;
Miklos Szeredic3021622010-05-25 15:06:07 +02001381out:
1382 for (; page_nr < cs.nr_segs; page_nr++)
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +03001383 put_page(bufs[page_nr].page);
Miklos Szeredic3021622010-05-25 15:06:07 +02001384
1385 kfree(bufs);
1386 return ret;
1387}
1388
Tejun Heo95668a62008-11-26 12:03:55 +01001389static int fuse_notify_poll(struct fuse_conn *fc, unsigned int size,
1390 struct fuse_copy_state *cs)
1391{
1392 struct fuse_notify_poll_wakeup_out outarg;
Miklos Szeredif6d47a12009-01-26 15:00:59 +01001393 int err = -EINVAL;
Tejun Heo95668a62008-11-26 12:03:55 +01001394
1395 if (size != sizeof(outarg))
Miklos Szeredif6d47a12009-01-26 15:00:59 +01001396 goto err;
Tejun Heo95668a62008-11-26 12:03:55 +01001397
1398 err = fuse_copy_one(cs, &outarg, sizeof(outarg));
1399 if (err)
Miklos Szeredif6d47a12009-01-26 15:00:59 +01001400 goto err;
Tejun Heo95668a62008-11-26 12:03:55 +01001401
Miklos Szeredif6d47a12009-01-26 15:00:59 +01001402 fuse_copy_finish(cs);
Tejun Heo95668a62008-11-26 12:03:55 +01001403 return fuse_notify_poll_wakeup(fc, &outarg);
Miklos Szeredif6d47a12009-01-26 15:00:59 +01001404
1405err:
1406 fuse_copy_finish(cs);
1407 return err;
Tejun Heo95668a62008-11-26 12:03:55 +01001408}
1409
John Muir3b463ae2009-05-31 11:13:57 -04001410static int fuse_notify_inval_inode(struct fuse_conn *fc, unsigned int size,
1411 struct fuse_copy_state *cs)
1412{
1413 struct fuse_notify_inval_inode_out outarg;
1414 int err = -EINVAL;
1415
1416 if (size != sizeof(outarg))
1417 goto err;
1418
1419 err = fuse_copy_one(cs, &outarg, sizeof(outarg));
1420 if (err)
1421 goto err;
1422 fuse_copy_finish(cs);
1423
1424 down_read(&fc->killsb);
1425 err = -ENOENT;
Miklos Szeredib21dda42010-02-05 12:08:31 +01001426 if (fc->sb) {
1427 err = fuse_reverse_inval_inode(fc->sb, outarg.ino,
1428 outarg.off, outarg.len);
1429 }
John Muir3b463ae2009-05-31 11:13:57 -04001430 up_read(&fc->killsb);
1431 return err;
1432
1433err:
1434 fuse_copy_finish(cs);
1435 return err;
1436}
1437
1438static int fuse_notify_inval_entry(struct fuse_conn *fc, unsigned int size,
1439 struct fuse_copy_state *cs)
1440{
1441 struct fuse_notify_inval_entry_out outarg;
Fang Wenqib2d82ee2009-12-30 18:37:13 +08001442 int err = -ENOMEM;
1443 char *buf;
John Muir3b463ae2009-05-31 11:13:57 -04001444 struct qstr name;
1445
Fang Wenqib2d82ee2009-12-30 18:37:13 +08001446 buf = kzalloc(FUSE_NAME_MAX + 1, GFP_KERNEL);
1447 if (!buf)
1448 goto err;
1449
1450 err = -EINVAL;
John Muir3b463ae2009-05-31 11:13:57 -04001451 if (size < sizeof(outarg))
1452 goto err;
1453
1454 err = fuse_copy_one(cs, &outarg, sizeof(outarg));
1455 if (err)
1456 goto err;
1457
1458 err = -ENAMETOOLONG;
1459 if (outarg.namelen > FUSE_NAME_MAX)
1460 goto err;
1461
Miklos Szeredic2183d12011-08-24 10:20:17 +02001462 err = -EINVAL;
1463 if (size != sizeof(outarg) + outarg.namelen + 1)
1464 goto err;
1465
John Muir3b463ae2009-05-31 11:13:57 -04001466 name.name = buf;
1467 name.len = outarg.namelen;
1468 err = fuse_copy_one(cs, buf, outarg.namelen + 1);
1469 if (err)
1470 goto err;
1471 fuse_copy_finish(cs);
1472 buf[outarg.namelen] = 0;
John Muir3b463ae2009-05-31 11:13:57 -04001473
1474 down_read(&fc->killsb);
1475 err = -ENOENT;
Miklos Szeredib21dda42010-02-05 12:08:31 +01001476 if (fc->sb)
John Muir451d0f52011-12-06 21:50:06 +01001477 err = fuse_reverse_inval_entry(fc->sb, outarg.parent, 0, &name);
1478 up_read(&fc->killsb);
1479 kfree(buf);
1480 return err;
1481
1482err:
1483 kfree(buf);
1484 fuse_copy_finish(cs);
1485 return err;
1486}
1487
1488static int fuse_notify_delete(struct fuse_conn *fc, unsigned int size,
1489 struct fuse_copy_state *cs)
1490{
1491 struct fuse_notify_delete_out outarg;
1492 int err = -ENOMEM;
1493 char *buf;
1494 struct qstr name;
1495
1496 buf = kzalloc(FUSE_NAME_MAX + 1, GFP_KERNEL);
1497 if (!buf)
1498 goto err;
1499
1500 err = -EINVAL;
1501 if (size < sizeof(outarg))
1502 goto err;
1503
1504 err = fuse_copy_one(cs, &outarg, sizeof(outarg));
1505 if (err)
1506 goto err;
1507
1508 err = -ENAMETOOLONG;
1509 if (outarg.namelen > FUSE_NAME_MAX)
1510 goto err;
1511
1512 err = -EINVAL;
1513 if (size != sizeof(outarg) + outarg.namelen + 1)
1514 goto err;
1515
1516 name.name = buf;
1517 name.len = outarg.namelen;
1518 err = fuse_copy_one(cs, buf, outarg.namelen + 1);
1519 if (err)
1520 goto err;
1521 fuse_copy_finish(cs);
1522 buf[outarg.namelen] = 0;
John Muir451d0f52011-12-06 21:50:06 +01001523
1524 down_read(&fc->killsb);
1525 err = -ENOENT;
1526 if (fc->sb)
1527 err = fuse_reverse_inval_entry(fc->sb, outarg.parent,
1528 outarg.child, &name);
John Muir3b463ae2009-05-31 11:13:57 -04001529 up_read(&fc->killsb);
Fang Wenqib2d82ee2009-12-30 18:37:13 +08001530 kfree(buf);
John Muir3b463ae2009-05-31 11:13:57 -04001531 return err;
1532
1533err:
Fang Wenqib2d82ee2009-12-30 18:37:13 +08001534 kfree(buf);
John Muir3b463ae2009-05-31 11:13:57 -04001535 fuse_copy_finish(cs);
1536 return err;
1537}
1538
Miklos Szeredia1d75f22010-07-12 14:41:40 +02001539static int fuse_notify_store(struct fuse_conn *fc, unsigned int size,
1540 struct fuse_copy_state *cs)
1541{
1542 struct fuse_notify_store_out outarg;
1543 struct inode *inode;
1544 struct address_space *mapping;
1545 u64 nodeid;
1546 int err;
1547 pgoff_t index;
1548 unsigned int offset;
1549 unsigned int num;
1550 loff_t file_size;
1551 loff_t end;
1552
1553 err = -EINVAL;
1554 if (size < sizeof(outarg))
1555 goto out_finish;
1556
1557 err = fuse_copy_one(cs, &outarg, sizeof(outarg));
1558 if (err)
1559 goto out_finish;
1560
1561 err = -EINVAL;
1562 if (size - sizeof(outarg) != outarg.size)
1563 goto out_finish;
1564
1565 nodeid = outarg.nodeid;
1566
1567 down_read(&fc->killsb);
1568
1569 err = -ENOENT;
1570 if (!fc->sb)
1571 goto out_up_killsb;
1572
1573 inode = ilookup5(fc->sb, nodeid, fuse_inode_eq, &nodeid);
1574 if (!inode)
1575 goto out_up_killsb;
1576
1577 mapping = inode->i_mapping;
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +03001578 index = outarg.offset >> PAGE_SHIFT;
1579 offset = outarg.offset & ~PAGE_MASK;
Miklos Szeredia1d75f22010-07-12 14:41:40 +02001580 file_size = i_size_read(inode);
1581 end = outarg.offset + outarg.size;
1582 if (end > file_size) {
1583 file_size = end;
1584 fuse_write_update_size(inode, file_size);
1585 }
1586
1587 num = outarg.size;
1588 while (num) {
1589 struct page *page;
1590 unsigned int this_num;
1591
1592 err = -ENOMEM;
1593 page = find_or_create_page(mapping, index,
1594 mapping_gfp_mask(mapping));
1595 if (!page)
1596 goto out_iput;
1597
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +03001598 this_num = min_t(unsigned, num, PAGE_SIZE - offset);
Miklos Szeredia1d75f22010-07-12 14:41:40 +02001599 err = fuse_copy_page(cs, &page, offset, this_num, 0);
Miklos Szeredi063ec1e2014-01-22 19:36:58 +01001600 if (!err && offset == 0 &&
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +03001601 (this_num == PAGE_SIZE || file_size == end))
Miklos Szeredia1d75f22010-07-12 14:41:40 +02001602 SetPageUptodate(page);
1603 unlock_page(page);
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +03001604 put_page(page);
Miklos Szeredia1d75f22010-07-12 14:41:40 +02001605
1606 if (err)
1607 goto out_iput;
1608
1609 num -= this_num;
1610 offset = 0;
1611 index++;
1612 }
1613
1614 err = 0;
1615
1616out_iput:
1617 iput(inode);
1618out_up_killsb:
1619 up_read(&fc->killsb);
1620out_finish:
1621 fuse_copy_finish(cs);
1622 return err;
1623}
1624
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001625static void fuse_retrieve_end(struct fuse_conn *fc, struct fuse_req *req)
1626{
Mel Gormanb745bc82014-06-04 16:10:22 -07001627 release_pages(req->pages, req->num_pages, false);
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001628}
1629
1630static int fuse_retrieve(struct fuse_conn *fc, struct inode *inode,
1631 struct fuse_notify_retrieve_out *outarg)
1632{
1633 int err;
1634 struct address_space *mapping = inode->i_mapping;
1635 struct fuse_req *req;
1636 pgoff_t index;
1637 loff_t file_size;
1638 unsigned int num;
1639 unsigned int offset;
Geert Uytterhoeven01574432010-09-30 22:06:21 +02001640 size_t total_len = 0;
Maxim Patlasov4d53dc92012-10-26 19:48:42 +04001641 int num_pages;
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001642
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +03001643 offset = outarg->offset & ~PAGE_MASK;
Maxim Patlasov4d53dc92012-10-26 19:48:42 +04001644 file_size = i_size_read(inode);
1645
1646 num = outarg->size;
1647 if (outarg->offset > file_size)
1648 num = 0;
1649 else if (outarg->offset + num > file_size)
1650 num = file_size - outarg->offset;
1651
1652 num_pages = (num + offset + PAGE_SIZE - 1) >> PAGE_SHIFT;
1653 num_pages = min(num_pages, FUSE_MAX_PAGES_PER_REQ);
1654
1655 req = fuse_get_req(fc, num_pages);
1656 if (IS_ERR(req))
1657 return PTR_ERR(req);
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001658
1659 req->in.h.opcode = FUSE_NOTIFY_REPLY;
1660 req->in.h.nodeid = outarg->nodeid;
1661 req->in.numargs = 2;
1662 req->in.argpages = 1;
Maxim Patlasovb2430d72012-10-26 19:49:24 +04001663 req->page_descs[0].offset = offset;
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001664 req->end = fuse_retrieve_end;
1665
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +03001666 index = outarg->offset >> PAGE_SHIFT;
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001667
Maxim Patlasov4d53dc92012-10-26 19:48:42 +04001668 while (num && req->num_pages < num_pages) {
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001669 struct page *page;
1670 unsigned int this_num;
1671
1672 page = find_get_page(mapping, index);
1673 if (!page)
1674 break;
1675
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +03001676 this_num = min_t(unsigned, num, PAGE_SIZE - offset);
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001677 req->pages[req->num_pages] = page;
Maxim Patlasov85f40ae2012-10-26 19:49:33 +04001678 req->page_descs[req->num_pages].length = this_num;
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001679 req->num_pages++;
1680
Miklos Szeredic9e67d42012-09-04 18:45:54 +02001681 offset = 0;
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001682 num -= this_num;
1683 total_len += this_num;
Miklos Szeredi48706d02011-12-13 10:36:59 +01001684 index++;
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001685 }
1686 req->misc.retrieve_in.offset = outarg->offset;
1687 req->misc.retrieve_in.size = total_len;
1688 req->in.args[0].size = sizeof(req->misc.retrieve_in);
1689 req->in.args[0].value = &req->misc.retrieve_in;
1690 req->in.args[1].size = total_len;
1691
1692 err = fuse_request_send_notify_reply(fc, req, outarg->notify_unique);
1693 if (err)
1694 fuse_retrieve_end(fc, req);
1695
1696 return err;
1697}
1698
1699static int fuse_notify_retrieve(struct fuse_conn *fc, unsigned int size,
1700 struct fuse_copy_state *cs)
1701{
1702 struct fuse_notify_retrieve_out outarg;
1703 struct inode *inode;
1704 int err;
1705
1706 err = -EINVAL;
1707 if (size != sizeof(outarg))
1708 goto copy_finish;
1709
1710 err = fuse_copy_one(cs, &outarg, sizeof(outarg));
1711 if (err)
1712 goto copy_finish;
1713
1714 fuse_copy_finish(cs);
1715
1716 down_read(&fc->killsb);
1717 err = -ENOENT;
1718 if (fc->sb) {
1719 u64 nodeid = outarg.nodeid;
1720
1721 inode = ilookup5(fc->sb, nodeid, fuse_inode_eq, &nodeid);
1722 if (inode) {
1723 err = fuse_retrieve(fc, inode, &outarg);
1724 iput(inode);
1725 }
1726 }
1727 up_read(&fc->killsb);
1728
1729 return err;
1730
1731copy_finish:
1732 fuse_copy_finish(cs);
1733 return err;
1734}
1735
Tejun Heo85993962008-11-26 12:03:55 +01001736static int fuse_notify(struct fuse_conn *fc, enum fuse_notify_code code,
1737 unsigned int size, struct fuse_copy_state *cs)
1738{
Miklos Szeredi0d278362015-02-26 11:45:47 +01001739 /* Don't try to move pages (yet) */
1740 cs->move_pages = 0;
1741
Tejun Heo85993962008-11-26 12:03:55 +01001742 switch (code) {
Tejun Heo95668a62008-11-26 12:03:55 +01001743 case FUSE_NOTIFY_POLL:
1744 return fuse_notify_poll(fc, size, cs);
1745
John Muir3b463ae2009-05-31 11:13:57 -04001746 case FUSE_NOTIFY_INVAL_INODE:
1747 return fuse_notify_inval_inode(fc, size, cs);
1748
1749 case FUSE_NOTIFY_INVAL_ENTRY:
1750 return fuse_notify_inval_entry(fc, size, cs);
1751
Miklos Szeredia1d75f22010-07-12 14:41:40 +02001752 case FUSE_NOTIFY_STORE:
1753 return fuse_notify_store(fc, size, cs);
1754
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001755 case FUSE_NOTIFY_RETRIEVE:
1756 return fuse_notify_retrieve(fc, size, cs);
1757
John Muir451d0f52011-12-06 21:50:06 +01001758 case FUSE_NOTIFY_DELETE:
1759 return fuse_notify_delete(fc, size, cs);
1760
Tejun Heo85993962008-11-26 12:03:55 +01001761 default:
Miklos Szeredif6d47a12009-01-26 15:00:59 +01001762 fuse_copy_finish(cs);
Tejun Heo85993962008-11-26 12:03:55 +01001763 return -EINVAL;
1764 }
1765}
1766
Miklos Szeredi334f4852005-09-09 13:10:27 -07001767/* Look up request on processing list by unique ID */
Miklos Szeredi3a2b5b92015-07-01 16:26:04 +02001768static struct fuse_req *request_find(struct fuse_pqueue *fpq, u64 unique)
Miklos Szeredi334f4852005-09-09 13:10:27 -07001769{
Dong Fang05726ac2013-07-30 22:50:01 -04001770 struct fuse_req *req;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001771
Miklos Szeredi3a2b5b92015-07-01 16:26:04 +02001772 list_for_each_entry(req, &fpq->processing, list) {
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001773 if (req->in.h.unique == unique || req->intr_unique == unique)
Miklos Szeredi334f4852005-09-09 13:10:27 -07001774 return req;
1775 }
1776 return NULL;
1777}
1778
1779static int copy_out_args(struct fuse_copy_state *cs, struct fuse_out *out,
1780 unsigned nbytes)
1781{
1782 unsigned reqsize = sizeof(struct fuse_out_header);
1783
1784 if (out->h.error)
1785 return nbytes != reqsize ? -EINVAL : 0;
1786
1787 reqsize += len_args(out->numargs, out->args);
1788
1789 if (reqsize < nbytes || (reqsize > nbytes && !out->argvar))
1790 return -EINVAL;
1791 else if (reqsize > nbytes) {
1792 struct fuse_arg *lastarg = &out->args[out->numargs-1];
1793 unsigned diffsize = reqsize - nbytes;
1794 if (diffsize > lastarg->size)
1795 return -EINVAL;
1796 lastarg->size -= diffsize;
1797 }
1798 return fuse_copy_args(cs, out->numargs, out->argpages, out->args,
1799 out->page_zeroing);
1800}
1801
1802/*
1803 * Write a single reply to a request. First the header is copied from
1804 * the write buffer. The request is then searched on the processing
1805 * list by the unique ID found in the header. If found, then remove
1806 * it from the list and copy the rest of the buffer to the request.
1807 * The request is finished by calling request_end()
1808 */
Miklos Szeredic36960462015-07-01 16:26:09 +02001809static ssize_t fuse_dev_do_write(struct fuse_dev *fud,
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001810 struct fuse_copy_state *cs, size_t nbytes)
Miklos Szeredi334f4852005-09-09 13:10:27 -07001811{
1812 int err;
Miklos Szeredic36960462015-07-01 16:26:09 +02001813 struct fuse_conn *fc = fud->fc;
1814 struct fuse_pqueue *fpq = &fud->pq;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001815 struct fuse_req *req;
1816 struct fuse_out_header oh;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001817
Miklos Szeredi334f4852005-09-09 13:10:27 -07001818 if (nbytes < sizeof(struct fuse_out_header))
1819 return -EINVAL;
1820
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001821 err = fuse_copy_one(cs, &oh, sizeof(oh));
Miklos Szeredi334f4852005-09-09 13:10:27 -07001822 if (err)
1823 goto err_finish;
Tejun Heo85993962008-11-26 12:03:55 +01001824
Miklos Szeredi334f4852005-09-09 13:10:27 -07001825 err = -EINVAL;
Tejun Heo85993962008-11-26 12:03:55 +01001826 if (oh.len != nbytes)
1827 goto err_finish;
1828
1829 /*
1830 * Zero oh.unique indicates unsolicited notification message
1831 * and error contains notification code.
1832 */
1833 if (!oh.unique) {
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001834 err = fuse_notify(fc, oh.error, nbytes - sizeof(oh), cs);
Tejun Heo85993962008-11-26 12:03:55 +01001835 return err ? err : nbytes;
1836 }
1837
1838 err = -EINVAL;
1839 if (oh.error <= -1000 || oh.error > 0)
Miklos Szeredi334f4852005-09-09 13:10:27 -07001840 goto err_finish;
1841
Miklos Szeredi45a91cb2015-07-01 16:26:06 +02001842 spin_lock(&fpq->lock);
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08001843 err = -ENOENT;
Miklos Szeredie96edd92015-07-01 16:26:04 +02001844 if (!fpq->connected)
Miklos Szeredi45a91cb2015-07-01 16:26:06 +02001845 goto err_unlock_pq;
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08001846
Miklos Szeredi3a2b5b92015-07-01 16:26:04 +02001847 req = request_find(fpq, oh.unique);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001848 if (!req)
Miklos Szeredi45a91cb2015-07-01 16:26:06 +02001849 goto err_unlock_pq;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001850
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001851 /* Is it an interrupt reply? */
1852 if (req->intr_unique == oh.unique) {
Miklos Szeredi45a91cb2015-07-01 16:26:06 +02001853 spin_unlock(&fpq->lock);
1854
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001855 err = -EINVAL;
1856 if (nbytes != sizeof(struct fuse_out_header))
Miklos Szeredi46c34a32015-07-01 16:26:07 +02001857 goto err_finish;
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001858
1859 if (oh.error == -ENOSYS)
1860 fc->no_interrupt = 1;
1861 else if (oh.error == -EAGAIN)
Miklos Szeredif88996a2015-07-01 16:26:01 +02001862 queue_interrupt(&fc->iq, req);
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001863
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001864 fuse_copy_finish(cs);
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001865 return nbytes;
1866 }
1867
Miklos Szeredi33e14b42015-07-01 16:26:01 +02001868 clear_bit(FR_SENT, &req->flags);
Miklos Szeredi3a2b5b92015-07-01 16:26:04 +02001869 list_move(&req->list, &fpq->io);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001870 req->out.h = oh;
Miklos Szeredi825d6d32015-07-01 16:25:58 +02001871 set_bit(FR_LOCKED, &req->flags);
Miklos Szeredi45a91cb2015-07-01 16:26:06 +02001872 spin_unlock(&fpq->lock);
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001873 cs->req = req;
Miklos Szeredice534fb2010-05-25 15:06:07 +02001874 if (!req->out.page_replace)
1875 cs->move_pages = 0;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001876
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001877 err = copy_out_args(cs, &req->out, nbytes);
1878 fuse_copy_finish(cs);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001879
Miklos Szeredi45a91cb2015-07-01 16:26:06 +02001880 spin_lock(&fpq->lock);
Miklos Szeredi825d6d32015-07-01 16:25:58 +02001881 clear_bit(FR_LOCKED, &req->flags);
Miklos Szeredie96edd92015-07-01 16:26:04 +02001882 if (!fpq->connected)
Miklos Szeredi0d8e84b2015-07-01 16:25:58 +02001883 err = -ENOENT;
1884 else if (err)
Miklos Szeredi334f4852005-09-09 13:10:27 -07001885 req->out.h.error = -EIO;
Miklos Szeredi77cd9d42015-07-01 16:26:06 +02001886 if (!test_bit(FR_PRIVATE, &req->flags))
1887 list_del_init(&req->list);
Miklos Szeredi45a91cb2015-07-01 16:26:06 +02001888 spin_unlock(&fpq->lock);
Miklos Szeredi46c34a32015-07-01 16:26:07 +02001889
Miklos Szeredi334f4852005-09-09 13:10:27 -07001890 request_end(fc, req);
1891
1892 return err ? err : nbytes;
1893
Miklos Szeredi45a91cb2015-07-01 16:26:06 +02001894 err_unlock_pq:
1895 spin_unlock(&fpq->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001896 err_finish:
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001897 fuse_copy_finish(cs);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001898 return err;
1899}
1900
Al Virofbdbacc2015-04-03 21:53:39 -04001901static ssize_t fuse_dev_write(struct kiocb *iocb, struct iov_iter *from)
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001902{
1903 struct fuse_copy_state cs;
Miklos Szeredicc080e92015-07-01 16:26:08 +02001904 struct fuse_dev *fud = fuse_get_dev(iocb->ki_filp);
1905
1906 if (!fud)
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001907 return -EPERM;
1908
Al Virofbdbacc2015-04-03 21:53:39 -04001909 if (!iter_is_iovec(from))
1910 return -EINVAL;
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001911
Miklos Szeredidc008092015-07-01 16:25:58 +02001912 fuse_copy_init(&cs, 0, from);
Al Virofbdbacc2015-04-03 21:53:39 -04001913
Miklos Szeredic36960462015-07-01 16:26:09 +02001914 return fuse_dev_do_write(fud, &cs, iov_iter_count(from));
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001915}
1916
1917static ssize_t fuse_dev_splice_write(struct pipe_inode_info *pipe,
1918 struct file *out, loff_t *ppos,
1919 size_t len, unsigned int flags)
1920{
1921 unsigned nbuf;
1922 unsigned idx;
1923 struct pipe_buffer *bufs;
1924 struct fuse_copy_state cs;
Miklos Szeredicc080e92015-07-01 16:26:08 +02001925 struct fuse_dev *fud;
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001926 size_t rem;
1927 ssize_t ret;
1928
Miklos Szeredicc080e92015-07-01 16:26:08 +02001929 fud = fuse_get_dev(out);
1930 if (!fud)
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001931 return -EPERM;
1932
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001933 bufs = kmalloc(pipe->buffers * sizeof(struct pipe_buffer), GFP_KERNEL);
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001934 if (!bufs)
1935 return -ENOMEM;
1936
1937 pipe_lock(pipe);
1938 nbuf = 0;
1939 rem = 0;
1940 for (idx = 0; idx < pipe->nrbufs && rem < len; idx++)
1941 rem += pipe->bufs[(pipe->curbuf + idx) & (pipe->buffers - 1)].len;
1942
1943 ret = -EINVAL;
1944 if (rem < len) {
1945 pipe_unlock(pipe);
1946 goto out;
1947 }
1948
1949 rem = len;
1950 while (rem) {
1951 struct pipe_buffer *ibuf;
1952 struct pipe_buffer *obuf;
1953
1954 BUG_ON(nbuf >= pipe->buffers);
1955 BUG_ON(!pipe->nrbufs);
1956 ibuf = &pipe->bufs[pipe->curbuf];
1957 obuf = &bufs[nbuf];
1958
1959 if (rem >= ibuf->len) {
1960 *obuf = *ibuf;
1961 ibuf->ops = NULL;
1962 pipe->curbuf = (pipe->curbuf + 1) & (pipe->buffers - 1);
1963 pipe->nrbufs--;
1964 } else {
Miklos Szeredi7bf2d1d2016-09-27 10:45:12 +02001965 pipe_buf_get(pipe, ibuf);
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001966 *obuf = *ibuf;
1967 obuf->flags &= ~PIPE_BUF_FLAG_GIFT;
1968 obuf->len = rem;
1969 ibuf->offset += obuf->len;
1970 ibuf->len -= obuf->len;
1971 }
1972 nbuf++;
1973 rem -= obuf->len;
1974 }
1975 pipe_unlock(pipe);
1976
Miklos Szeredidc008092015-07-01 16:25:58 +02001977 fuse_copy_init(&cs, 0, NULL);
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001978 cs.pipebufs = bufs;
Al Viro6c09e942015-04-03 22:06:08 -04001979 cs.nr_segs = nbuf;
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001980 cs.pipe = pipe;
1981
Miklos Szeredice534fb2010-05-25 15:06:07 +02001982 if (flags & SPLICE_F_MOVE)
1983 cs.move_pages = 1;
1984
Miklos Szeredic36960462015-07-01 16:26:09 +02001985 ret = fuse_dev_do_write(fud, &cs, len);
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001986
Miklos Szeredia7796382016-09-27 10:45:12 +02001987 for (idx = 0; idx < nbuf; idx++)
1988 pipe_buf_release(pipe, &bufs[idx]);
1989
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001990out:
1991 kfree(bufs);
1992 return ret;
1993}
1994
Miklos Szeredi334f4852005-09-09 13:10:27 -07001995static unsigned fuse_dev_poll(struct file *file, poll_table *wait)
1996{
Miklos Szeredi334f4852005-09-09 13:10:27 -07001997 unsigned mask = POLLOUT | POLLWRNORM;
Miklos Szeredif88996a2015-07-01 16:26:01 +02001998 struct fuse_iqueue *fiq;
Miklos Szeredicc080e92015-07-01 16:26:08 +02001999 struct fuse_dev *fud = fuse_get_dev(file);
2000
2001 if (!fud)
Miklos Szeredi7025d9a2006-04-10 22:54:50 -07002002 return POLLERR;
Miklos Szeredi334f4852005-09-09 13:10:27 -07002003
Miklos Szeredicc080e92015-07-01 16:26:08 +02002004 fiq = &fud->fc->iq;
Miklos Szeredif88996a2015-07-01 16:26:01 +02002005 poll_wait(file, &fiq->waitq, wait);
Miklos Szeredi334f4852005-09-09 13:10:27 -07002006
Miklos Szeredi4ce60812015-07-01 16:26:02 +02002007 spin_lock(&fiq->waitq.lock);
Miklos Szeredie16714d2015-07-01 16:26:01 +02002008 if (!fiq->connected)
Miklos Szeredi7025d9a2006-04-10 22:54:50 -07002009 mask = POLLERR;
Miklos Szeredif88996a2015-07-01 16:26:01 +02002010 else if (request_pending(fiq))
Miklos Szeredi7025d9a2006-04-10 22:54:50 -07002011 mask |= POLLIN | POLLRDNORM;
Miklos Szeredi4ce60812015-07-01 16:26:02 +02002012 spin_unlock(&fiq->waitq.lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -07002013
2014 return mask;
2015}
2016
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002017/*
2018 * Abort all requests on the given list (pending or processing)
2019 *
Miklos Szeredid7133112006-04-10 22:54:55 -07002020 * This function releases and reacquires fc->lock
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002021 */
Miklos Szeredi334f4852005-09-09 13:10:27 -07002022static void end_requests(struct fuse_conn *fc, struct list_head *head)
2023{
2024 while (!list_empty(head)) {
2025 struct fuse_req *req;
2026 req = list_entry(head->next, struct fuse_req, list);
Miklos Szeredi334f4852005-09-09 13:10:27 -07002027 req->out.h.error = -ECONNABORTED;
Miklos Szeredi33e14b42015-07-01 16:26:01 +02002028 clear_bit(FR_PENDING, &req->flags);
2029 clear_bit(FR_SENT, &req->flags);
Miklos Szeredif377cb72015-07-01 16:26:04 +02002030 list_del_init(&req->list);
Miklos Szeredi334f4852005-09-09 13:10:27 -07002031 request_end(fc, req);
Miklos Szeredi334f4852005-09-09 13:10:27 -07002032 }
2033}
2034
Bryan Green357ccf22011-03-01 16:43:52 -08002035static void end_polls(struct fuse_conn *fc)
2036{
2037 struct rb_node *p;
2038
2039 p = rb_first(&fc->polled_files);
2040
2041 while (p) {
2042 struct fuse_file *ff;
2043 ff = rb_entry(p, struct fuse_file, polled_node);
2044 wake_up_interruptible_all(&ff->poll_wait);
2045
2046 p = rb_next(p);
2047 }
2048}
2049
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002050/*
2051 * Abort all requests.
2052 *
Miklos Szeredib716d422015-07-01 16:25:59 +02002053 * Emergency exit in case of a malicious or accidental deadlock, or just a hung
2054 * filesystem.
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002055 *
Miklos Szeredib716d422015-07-01 16:25:59 +02002056 * The same effect is usually achievable through killing the filesystem daemon
2057 * and all users of the filesystem. The exception is the combination of an
2058 * asynchronous request and the tricky deadlock (see
2059 * Documentation/filesystems/fuse.txt).
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002060 *
Miklos Szeredib716d422015-07-01 16:25:59 +02002061 * Aborting requests under I/O goes as follows: 1: Separate out unlocked
2062 * requests, they should be finished off immediately. Locked requests will be
2063 * finished after unlock; see unlock_request(). 2: Finish off the unlocked
2064 * requests. It is possible that some request will finish before we can. This
2065 * is OK, the request will in that case be removed from the list before we touch
2066 * it.
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002067 */
2068void fuse_abort_conn(struct fuse_conn *fc)
2069{
Miklos Szeredif88996a2015-07-01 16:26:01 +02002070 struct fuse_iqueue *fiq = &fc->iq;
2071
Miklos Szeredid7133112006-04-10 22:54:55 -07002072 spin_lock(&fc->lock);
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002073 if (fc->connected) {
Miklos Szeredic36960462015-07-01 16:26:09 +02002074 struct fuse_dev *fud;
Miklos Szeredib716d422015-07-01 16:25:59 +02002075 struct fuse_req *req, *next;
Miklos Szeredi41f98272015-07-01 16:25:59 +02002076 LIST_HEAD(to_end1);
2077 LIST_HEAD(to_end2);
Miklos Szeredib716d422015-07-01 16:25:59 +02002078
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002079 fc->connected = 0;
Miklos Szeredi51eb01e2006-06-25 05:48:50 -07002080 fc->blocked = 0;
Miklos Szeredi9759bd512015-01-06 10:45:35 +01002081 fuse_set_initialized(fc);
Miklos Szeredic36960462015-07-01 16:26:09 +02002082 list_for_each_entry(fud, &fc->devices, entry) {
2083 struct fuse_pqueue *fpq = &fud->pq;
2084
2085 spin_lock(&fpq->lock);
2086 fpq->connected = 0;
2087 list_for_each_entry_safe(req, next, &fpq->io, list) {
2088 req->out.h.error = -ECONNABORTED;
2089 spin_lock(&req->waitq.lock);
2090 set_bit(FR_ABORTED, &req->flags);
2091 if (!test_bit(FR_LOCKED, &req->flags)) {
2092 set_bit(FR_PRIVATE, &req->flags);
2093 list_move(&req->list, &to_end1);
2094 }
2095 spin_unlock(&req->waitq.lock);
Miklos Szeredi77cd9d42015-07-01 16:26:06 +02002096 }
Miklos Szeredic36960462015-07-01 16:26:09 +02002097 list_splice_init(&fpq->processing, &to_end2);
2098 spin_unlock(&fpq->lock);
Miklos Szeredib716d422015-07-01 16:25:59 +02002099 }
Miklos Szeredi41f98272015-07-01 16:25:59 +02002100 fc->max_background = UINT_MAX;
2101 flush_bg_queue(fc);
Miklos Szeredi8c911892015-07-01 16:26:02 +02002102
Miklos Szeredi4ce60812015-07-01 16:26:02 +02002103 spin_lock(&fiq->waitq.lock);
Miklos Szeredi8c911892015-07-01 16:26:02 +02002104 fiq->connected = 0;
Miklos Szeredif88996a2015-07-01 16:26:01 +02002105 list_splice_init(&fiq->pending, &to_end2);
Miklos Szeredi8c911892015-07-01 16:26:02 +02002106 while (forget_pending(fiq))
2107 kfree(dequeue_forget(fiq, 1, NULL));
Miklos Szeredi4ce60812015-07-01 16:26:02 +02002108 wake_up_all_locked(&fiq->waitq);
2109 spin_unlock(&fiq->waitq.lock);
Miklos Szeredi8c911892015-07-01 16:26:02 +02002110 kill_fasync(&fiq->fasync, SIGIO, POLL_IN);
Miklos Szerediee314a82015-07-01 16:26:08 +02002111 end_polls(fc);
2112 wake_up_all(&fc->blocked_waitq);
2113 spin_unlock(&fc->lock);
Miklos Szeredi8c911892015-07-01 16:26:02 +02002114
Miklos Szeredi41f98272015-07-01 16:25:59 +02002115 while (!list_empty(&to_end1)) {
2116 req = list_first_entry(&to_end1, struct fuse_req, list);
Miklos Szeredib716d422015-07-01 16:25:59 +02002117 __fuse_get_request(req);
Miklos Szeredif377cb72015-07-01 16:26:04 +02002118 list_del_init(&req->list);
Miklos Szeredib716d422015-07-01 16:25:59 +02002119 request_end(fc, req);
Miklos Szeredib716d422015-07-01 16:25:59 +02002120 }
Miklos Szeredi41f98272015-07-01 16:25:59 +02002121 end_requests(fc, &to_end2);
Miklos Szerediee314a82015-07-01 16:26:08 +02002122 } else {
2123 spin_unlock(&fc->lock);
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002124 }
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002125}
Tejun Heo08cbf542009-04-14 10:54:53 +09002126EXPORT_SYMBOL_GPL(fuse_abort_conn);
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002127
Tejun Heo08cbf542009-04-14 10:54:53 +09002128int fuse_dev_release(struct inode *inode, struct file *file)
Miklos Szeredi334f4852005-09-09 13:10:27 -07002129{
Miklos Szeredicc080e92015-07-01 16:26:08 +02002130 struct fuse_dev *fud = fuse_get_dev(file);
2131
2132 if (fud) {
2133 struct fuse_conn *fc = fud->fc;
Miklos Szeredic36960462015-07-01 16:26:09 +02002134 struct fuse_pqueue *fpq = &fud->pq;
Miklos Szeredicc080e92015-07-01 16:26:08 +02002135
Miklos Szeredic36960462015-07-01 16:26:09 +02002136 WARN_ON(!list_empty(&fpq->io));
2137 end_requests(fc, &fpq->processing);
2138 /* Are we the last open device? */
2139 if (atomic_dec_and_test(&fc->dev_count)) {
2140 WARN_ON(fc->iq.fasync != NULL);
2141 fuse_abort_conn(fc);
2142 }
Miklos Szeredicc080e92015-07-01 16:26:08 +02002143 fuse_dev_free(fud);
Jeff Dike385a17b2006-04-10 22:54:52 -07002144 }
Miklos Szeredi334f4852005-09-09 13:10:27 -07002145 return 0;
2146}
Tejun Heo08cbf542009-04-14 10:54:53 +09002147EXPORT_SYMBOL_GPL(fuse_dev_release);
Miklos Szeredi334f4852005-09-09 13:10:27 -07002148
Jeff Dike385a17b2006-04-10 22:54:52 -07002149static int fuse_dev_fasync(int fd, struct file *file, int on)
2150{
Miklos Szeredicc080e92015-07-01 16:26:08 +02002151 struct fuse_dev *fud = fuse_get_dev(file);
2152
2153 if (!fud)
Miklos Szeredia87046d2006-04-10 22:54:56 -07002154 return -EPERM;
Jeff Dike385a17b2006-04-10 22:54:52 -07002155
2156 /* No locking - fasync_helper does its own locking */
Miklos Szeredicc080e92015-07-01 16:26:08 +02002157 return fasync_helper(fd, file, on, &fud->fc->iq.fasync);
Jeff Dike385a17b2006-04-10 22:54:52 -07002158}
2159
Miklos Szeredi00c570f2015-07-01 16:26:08 +02002160static int fuse_device_clone(struct fuse_conn *fc, struct file *new)
2161{
Miklos Szeredicc080e92015-07-01 16:26:08 +02002162 struct fuse_dev *fud;
2163
Miklos Szeredi00c570f2015-07-01 16:26:08 +02002164 if (new->private_data)
2165 return -EINVAL;
2166
Miklos Szeredicc080e92015-07-01 16:26:08 +02002167 fud = fuse_dev_alloc(fc);
2168 if (!fud)
2169 return -ENOMEM;
2170
2171 new->private_data = fud;
Miklos Szeredic36960462015-07-01 16:26:09 +02002172 atomic_inc(&fc->dev_count);
Miklos Szeredi00c570f2015-07-01 16:26:08 +02002173
2174 return 0;
2175}
2176
2177static long fuse_dev_ioctl(struct file *file, unsigned int cmd,
2178 unsigned long arg)
2179{
2180 int err = -ENOTTY;
2181
2182 if (cmd == FUSE_DEV_IOC_CLONE) {
2183 int oldfd;
2184
2185 err = -EFAULT;
2186 if (!get_user(oldfd, (__u32 __user *) arg)) {
2187 struct file *old = fget(oldfd);
2188
2189 err = -EINVAL;
2190 if (old) {
Jann Horn8ed1f0e2015-08-16 20:27:01 +02002191 struct fuse_dev *fud = NULL;
2192
2193 /*
2194 * Check against file->f_op because CUSE
2195 * uses the same ioctl handler.
2196 */
2197 if (old->f_op == file->f_op &&
2198 old->f_cred->user_ns == file->f_cred->user_ns)
2199 fud = fuse_get_dev(old);
Miklos Szeredi00c570f2015-07-01 16:26:08 +02002200
Miklos Szeredicc080e92015-07-01 16:26:08 +02002201 if (fud) {
Miklos Szeredi00c570f2015-07-01 16:26:08 +02002202 mutex_lock(&fuse_mutex);
Miklos Szeredicc080e92015-07-01 16:26:08 +02002203 err = fuse_device_clone(fud->fc, file);
Miklos Szeredi00c570f2015-07-01 16:26:08 +02002204 mutex_unlock(&fuse_mutex);
2205 }
2206 fput(old);
2207 }
2208 }
2209 }
2210 return err;
2211}
2212
Arjan van de Ven4b6f5d22006-03-28 01:56:42 -08002213const struct file_operations fuse_dev_operations = {
Miklos Szeredi334f4852005-09-09 13:10:27 -07002214 .owner = THIS_MODULE,
Tom Van Braeckel94e4fe22015-01-12 05:22:16 +01002215 .open = fuse_dev_open,
Miklos Szeredi334f4852005-09-09 13:10:27 -07002216 .llseek = no_llseek,
Al Virofbdbacc2015-04-03 21:53:39 -04002217 .read_iter = fuse_dev_read,
Miklos Szeredic3021622010-05-25 15:06:07 +02002218 .splice_read = fuse_dev_splice_read,
Al Virofbdbacc2015-04-03 21:53:39 -04002219 .write_iter = fuse_dev_write,
Miklos Szeredidd3bb142010-05-25 15:06:06 +02002220 .splice_write = fuse_dev_splice_write,
Miklos Szeredi334f4852005-09-09 13:10:27 -07002221 .poll = fuse_dev_poll,
2222 .release = fuse_dev_release,
Jeff Dike385a17b2006-04-10 22:54:52 -07002223 .fasync = fuse_dev_fasync,
Miklos Szeredi00c570f2015-07-01 16:26:08 +02002224 .unlocked_ioctl = fuse_dev_ioctl,
2225 .compat_ioctl = fuse_dev_ioctl,
Miklos Szeredi334f4852005-09-09 13:10:27 -07002226};
Tejun Heo08cbf542009-04-14 10:54:53 +09002227EXPORT_SYMBOL_GPL(fuse_dev_operations);
Miklos Szeredi334f4852005-09-09 13:10:27 -07002228
2229static struct miscdevice fuse_miscdevice = {
2230 .minor = FUSE_MINOR,
2231 .name = "fuse",
2232 .fops = &fuse_dev_operations,
2233};
2234
2235int __init fuse_dev_init(void)
2236{
2237 int err = -ENOMEM;
2238 fuse_req_cachep = kmem_cache_create("fuse_request",
2239 sizeof(struct fuse_req),
Paul Mundt20c2df82007-07-20 10:11:58 +09002240 0, 0, NULL);
Miklos Szeredi334f4852005-09-09 13:10:27 -07002241 if (!fuse_req_cachep)
2242 goto out;
2243
2244 err = misc_register(&fuse_miscdevice);
2245 if (err)
2246 goto out_cache_clean;
2247
2248 return 0;
2249
2250 out_cache_clean:
2251 kmem_cache_destroy(fuse_req_cachep);
2252 out:
2253 return err;
2254}
2255
2256void fuse_dev_cleanup(void)
2257{
2258 misc_deregister(&fuse_miscdevice);
2259 kmem_cache_destroy(fuse_req_cachep);
2260}