blob: 5d06384c2cae3c746ef2e2865956ea2871cd1c1c [file] [log] [blame]
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>
Ingo Molnar174cd4b2017-02-02 19:15:33 +010014#include <linux/sched/signal.h>
Miklos Szeredi334f4852005-09-09 13:10:27 -070015#include <linux/uio.h>
16#include <linux/miscdevice.h>
17#include <linux/pagemap.h>
18#include <linux/file.h>
19#include <linux/slab.h>
Miklos Szeredidd3bb142010-05-25 15:06:06 +020020#include <linux/pipe_fs_i.h>
Miklos Szeredice534fb2010-05-25 15:06:07 +020021#include <linux/swap.h>
22#include <linux/splice.h>
Seth Forshee0b6e9ea2014-07-02 16:29:19 -050023#include <linux/sched.h>
Miklos Szeredi334f4852005-09-09 13:10:27 -070024
25MODULE_ALIAS_MISCDEV(FUSE_MINOR);
Kay Sievers578454f2010-05-20 18:07:20 +020026MODULE_ALIAS("devname:fuse");
Miklos Szeredi334f4852005-09-09 13:10:27 -070027
Christoph Lametere18b8902006-12-06 20:33:20 -080028static struct kmem_cache *fuse_req_cachep;
Miklos Szeredi334f4852005-09-09 13:10:27 -070029
Miklos Szeredicc080e92015-07-01 16:26:08 +020030static struct fuse_dev *fuse_get_dev(struct file *file)
Miklos Szeredi334f4852005-09-09 13:10:27 -070031{
Miklos Szeredi0720b312006-04-10 22:54:55 -070032 /*
33 * Lockless access is OK, because file->private data is set
34 * once during mount and is valid until the file is released.
35 */
Mark Rutland6aa7de02017-10-23 14:07:29 -070036 return READ_ONCE(file->private_data);
Miklos Szeredi334f4852005-09-09 13:10:27 -070037}
38
Maxim Patlasov4250c062012-10-26 19:48:07 +040039static void fuse_request_init(struct fuse_req *req, struct page **pages,
Maxim Patlasovb2430d72012-10-26 19:49:24 +040040 struct fuse_page_desc *page_descs,
Maxim Patlasov4250c062012-10-26 19:48:07 +040041 unsigned npages)
Miklos Szeredi334f4852005-09-09 13:10:27 -070042{
43 memset(req, 0, sizeof(*req));
Maxim Patlasov4250c062012-10-26 19:48:07 +040044 memset(pages, 0, sizeof(*pages) * npages);
Maxim Patlasovb2430d72012-10-26 19:49:24 +040045 memset(page_descs, 0, sizeof(*page_descs) * npages);
Miklos Szeredi334f4852005-09-09 13:10:27 -070046 INIT_LIST_HEAD(&req->list);
Miklos Szeredia4d27e72006-06-25 05:48:54 -070047 INIT_LIST_HEAD(&req->intr_entry);
Miklos Szeredi334f4852005-09-09 13:10:27 -070048 init_waitqueue_head(&req->waitq);
Elena Reshetovaec99f6d2017-03-03 11:04:04 +020049 refcount_set(&req->count, 1);
Maxim Patlasov4250c062012-10-26 19:48:07 +040050 req->pages = pages;
Maxim Patlasovb2430d72012-10-26 19:49:24 +040051 req->page_descs = page_descs;
Maxim Patlasov4250c062012-10-26 19:48:07 +040052 req->max_pages = npages;
Miklos Szeredi33e14b42015-07-01 16:26:01 +020053 __set_bit(FR_PENDING, &req->flags);
Miklos Szeredi334f4852005-09-09 13:10:27 -070054}
55
Maxim Patlasov4250c062012-10-26 19:48:07 +040056static struct fuse_req *__fuse_request_alloc(unsigned npages, gfp_t flags)
Miklos Szeredi334f4852005-09-09 13:10:27 -070057{
Maxim Patlasov4250c062012-10-26 19:48:07 +040058 struct fuse_req *req = kmem_cache_alloc(fuse_req_cachep, flags);
59 if (req) {
60 struct page **pages;
Maxim Patlasovb2430d72012-10-26 19:49:24 +040061 struct fuse_page_desc *page_descs;
Maxim Patlasov4250c062012-10-26 19:48:07 +040062
Maxim Patlasovb2430d72012-10-26 19:49:24 +040063 if (npages <= FUSE_REQ_INLINE_PAGES) {
Maxim Patlasov4250c062012-10-26 19:48:07 +040064 pages = req->inline_pages;
Maxim Patlasovb2430d72012-10-26 19:49:24 +040065 page_descs = req->inline_page_descs;
66 } else {
Maxim Patlasov4250c062012-10-26 19:48:07 +040067 pages = kmalloc(sizeof(struct page *) * npages, flags);
Maxim Patlasovb2430d72012-10-26 19:49:24 +040068 page_descs = kmalloc(sizeof(struct fuse_page_desc) *
69 npages, flags);
70 }
Maxim Patlasov4250c062012-10-26 19:48:07 +040071
Maxim Patlasovb2430d72012-10-26 19:49:24 +040072 if (!pages || !page_descs) {
73 kfree(pages);
74 kfree(page_descs);
Maxim Patlasov4250c062012-10-26 19:48:07 +040075 kmem_cache_free(fuse_req_cachep, req);
76 return NULL;
77 }
78
Maxim Patlasovb2430d72012-10-26 19:49:24 +040079 fuse_request_init(req, pages, page_descs, npages);
Maxim Patlasov4250c062012-10-26 19:48:07 +040080 }
Miklos Szeredi334f4852005-09-09 13:10:27 -070081 return req;
82}
Maxim Patlasov4250c062012-10-26 19:48:07 +040083
84struct fuse_req *fuse_request_alloc(unsigned npages)
85{
86 return __fuse_request_alloc(npages, GFP_KERNEL);
87}
Tejun Heo08cbf542009-04-14 10:54:53 +090088EXPORT_SYMBOL_GPL(fuse_request_alloc);
Miklos Szeredi334f4852005-09-09 13:10:27 -070089
Maxim Patlasov4250c062012-10-26 19:48:07 +040090struct fuse_req *fuse_request_alloc_nofs(unsigned npages)
Miklos Szeredi3be5a522008-04-30 00:54:41 -070091{
Maxim Patlasov4250c062012-10-26 19:48:07 +040092 return __fuse_request_alloc(npages, GFP_NOFS);
Miklos Szeredi3be5a522008-04-30 00:54:41 -070093}
94
Miklos Szeredi334f4852005-09-09 13:10:27 -070095void fuse_request_free(struct fuse_req *req)
96{
Maxim Patlasovb2430d72012-10-26 19:49:24 +040097 if (req->pages != req->inline_pages) {
Maxim Patlasov4250c062012-10-26 19:48:07 +040098 kfree(req->pages);
Maxim Patlasovb2430d72012-10-26 19:49:24 +040099 kfree(req->page_descs);
100 }
Miklos Szeredi334f4852005-09-09 13:10:27 -0700101 kmem_cache_free(fuse_req_cachep, req);
102}
103
Maxim Patlasov36cf66e2012-12-14 19:20:51 +0400104void __fuse_get_request(struct fuse_req *req)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700105{
Elena Reshetovaec99f6d2017-03-03 11:04:04 +0200106 refcount_inc(&req->count);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700107}
108
109/* Must be called with > 1 refcount */
110static void __fuse_put_request(struct fuse_req *req)
111{
Elena Reshetovaec99f6d2017-03-03 11:04:04 +0200112 refcount_dec(&req->count);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700113}
114
Seth Forshee0b6e9ea2014-07-02 16:29:19 -0500115static void fuse_req_init_context(struct fuse_conn *fc, struct fuse_req *req)
Miklos Szeredi33649c92006-06-25 05:48:52 -0700116{
Eric W. Biederman499dcf22012-02-07 16:26:03 -0800117 req->in.h.uid = from_kuid_munged(&init_user_ns, current_fsuid());
118 req->in.h.gid = from_kgid_munged(&init_user_ns, current_fsgid());
Seth Forshee0b6e9ea2014-07-02 16:29:19 -0500119 req->in.h.pid = pid_nr_ns(task_pid(current), fc->pid_ns);
Miklos Szeredi33649c92006-06-25 05:48:52 -0700120}
121
Miklos Szeredi9759bd512015-01-06 10:45:35 +0100122void fuse_set_initialized(struct fuse_conn *fc)
123{
124 /* Make sure stores before this are seen on another CPU */
125 smp_wmb();
126 fc->initialized = 1;
127}
128
Maxim Patlasov0aada882013-03-21 18:02:28 +0400129static bool fuse_block_alloc(struct fuse_conn *fc, bool for_background)
130{
131 return !fc->initialized || (for_background && fc->blocked);
132}
133
Maxim Patlasov8b41e672013-03-21 18:02:04 +0400134static struct fuse_req *__fuse_get_req(struct fuse_conn *fc, unsigned npages,
135 bool for_background)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700136{
Miklos Szeredi08a53cd2006-04-10 22:54:59 -0700137 struct fuse_req *req;
Miklos Szeredi08a53cd2006-04-10 22:54:59 -0700138 int err;
Miklos Szeredi9bc5ddd2006-04-11 21:16:09 +0200139 atomic_inc(&fc->num_waiting);
Maxim Patlasov0aada882013-03-21 18:02:28 +0400140
141 if (fuse_block_alloc(fc, for_background)) {
Maxim Patlasov0aada882013-03-21 18:02:28 +0400142 err = -EINTR;
Al Viro7d3a07f2016-07-19 03:08:27 -0400143 if (wait_event_killable_exclusive(fc->blocked_waitq,
144 !fuse_block_alloc(fc, for_background)))
Maxim Patlasov0aada882013-03-21 18:02:28 +0400145 goto out;
146 }
Miklos Szeredi9759bd512015-01-06 10:45:35 +0100147 /* Matches smp_wmb() in fuse_set_initialized() */
148 smp_rmb();
Miklos Szeredi08a53cd2006-04-10 22:54:59 -0700149
Miklos Szeredi51eb01e2006-06-25 05:48:50 -0700150 err = -ENOTCONN;
151 if (!fc->connected)
152 goto out;
153
Miklos Szeredide155222015-07-01 16:25:57 +0200154 err = -ECONNREFUSED;
155 if (fc->conn_error)
156 goto out;
157
Maxim Patlasovb111c8c2012-10-26 19:48:30 +0400158 req = fuse_request_alloc(npages);
Miklos Szeredi9bc5ddd2006-04-11 21:16:09 +0200159 err = -ENOMEM;
Maxim Patlasov722d2be2013-03-21 18:02:36 +0400160 if (!req) {
161 if (for_background)
162 wake_up(&fc->blocked_waitq);
Miklos Szeredi9bc5ddd2006-04-11 21:16:09 +0200163 goto out;
Maxim Patlasov722d2be2013-03-21 18:02:36 +0400164 }
Miklos Szeredi334f4852005-09-09 13:10:27 -0700165
Seth Forshee0b6e9ea2014-07-02 16:29:19 -0500166 fuse_req_init_context(fc, req);
Miklos Szeredi825d6d32015-07-01 16:25:58 +0200167 __set_bit(FR_WAITING, &req->flags);
168 if (for_background)
169 __set_bit(FR_BACKGROUND, &req->flags);
170
Miklos Szeredi334f4852005-09-09 13:10:27 -0700171 return req;
Miklos Szeredi9bc5ddd2006-04-11 21:16:09 +0200172
173 out:
174 atomic_dec(&fc->num_waiting);
175 return ERR_PTR(err);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700176}
Maxim Patlasov8b41e672013-03-21 18:02:04 +0400177
178struct fuse_req *fuse_get_req(struct fuse_conn *fc, unsigned npages)
179{
180 return __fuse_get_req(fc, npages, false);
181}
Tejun Heo08cbf542009-04-14 10:54:53 +0900182EXPORT_SYMBOL_GPL(fuse_get_req);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700183
Maxim Patlasov8b41e672013-03-21 18:02:04 +0400184struct fuse_req *fuse_get_req_for_background(struct fuse_conn *fc,
185 unsigned npages)
186{
187 return __fuse_get_req(fc, npages, true);
188}
189EXPORT_SYMBOL_GPL(fuse_get_req_for_background);
190
Miklos Szeredi33649c92006-06-25 05:48:52 -0700191/*
192 * Return request in fuse_file->reserved_req. However that may
193 * currently be in use. If that is the case, wait for it to become
194 * available.
195 */
196static struct fuse_req *get_reserved_req(struct fuse_conn *fc,
197 struct file *file)
198{
199 struct fuse_req *req = NULL;
200 struct fuse_file *ff = file->private_data;
201
202 do {
Miklos Szeredide5e3de2007-10-16 23:31:00 -0700203 wait_event(fc->reserved_req_waitq, ff->reserved_req);
Miklos Szeredi33649c92006-06-25 05:48:52 -0700204 spin_lock(&fc->lock);
205 if (ff->reserved_req) {
206 req = ff->reserved_req;
207 ff->reserved_req = NULL;
Al Virocb0942b2012-08-27 14:48:26 -0400208 req->stolen_file = get_file(file);
Miklos Szeredi33649c92006-06-25 05:48:52 -0700209 }
210 spin_unlock(&fc->lock);
211 } while (!req);
212
213 return req;
214}
215
216/*
217 * Put stolen request back into fuse_file->reserved_req
218 */
219static void put_reserved_req(struct fuse_conn *fc, struct fuse_req *req)
220{
221 struct file *file = req->stolen_file;
222 struct fuse_file *ff = file->private_data;
223
224 spin_lock(&fc->lock);
Maxim Patlasovb2430d72012-10-26 19:49:24 +0400225 fuse_request_init(req, req->pages, req->page_descs, req->max_pages);
Miklos Szeredi33649c92006-06-25 05:48:52 -0700226 BUG_ON(ff->reserved_req);
227 ff->reserved_req = req;
Miklos Szeredide5e3de2007-10-16 23:31:00 -0700228 wake_up_all(&fc->reserved_req_waitq);
Miklos Szeredi33649c92006-06-25 05:48:52 -0700229 spin_unlock(&fc->lock);
230 fput(file);
231}
232
233/*
234 * Gets a requests for a file operation, always succeeds
235 *
236 * This is used for sending the FLUSH request, which must get to
237 * userspace, due to POSIX locks which may need to be unlocked.
238 *
239 * If allocation fails due to OOM, use the reserved request in
240 * fuse_file.
241 *
242 * This is very unlikely to deadlock accidentally, since the
243 * filesystem should not have it's own file open. If deadlock is
244 * intentional, it can still be broken by "aborting" the filesystem.
245 */
Maxim Patlasovb111c8c2012-10-26 19:48:30 +0400246struct fuse_req *fuse_get_req_nofail_nopages(struct fuse_conn *fc,
247 struct file *file)
Miklos Szeredi33649c92006-06-25 05:48:52 -0700248{
249 struct fuse_req *req;
250
251 atomic_inc(&fc->num_waiting);
Maxim Patlasov0aada882013-03-21 18:02:28 +0400252 wait_event(fc->blocked_waitq, fc->initialized);
Miklos Szeredi9759bd512015-01-06 10:45:35 +0100253 /* Matches smp_wmb() in fuse_set_initialized() */
254 smp_rmb();
Maxim Patlasovb111c8c2012-10-26 19:48:30 +0400255 req = fuse_request_alloc(0);
Miklos Szeredi33649c92006-06-25 05:48:52 -0700256 if (!req)
257 req = get_reserved_req(fc, file);
258
Seth Forshee0b6e9ea2014-07-02 16:29:19 -0500259 fuse_req_init_context(fc, req);
Miklos Szeredi825d6d32015-07-01 16:25:58 +0200260 __set_bit(FR_WAITING, &req->flags);
261 __clear_bit(FR_BACKGROUND, &req->flags);
Miklos Szeredi33649c92006-06-25 05:48:52 -0700262 return req;
263}
264
Miklos Szeredi334f4852005-09-09 13:10:27 -0700265void fuse_put_request(struct fuse_conn *fc, struct fuse_req *req)
266{
Elena Reshetovaec99f6d2017-03-03 11:04:04 +0200267 if (refcount_dec_and_test(&req->count)) {
Miklos Szeredi825d6d32015-07-01 16:25:58 +0200268 if (test_bit(FR_BACKGROUND, &req->flags)) {
Maxim Patlasov722d2be2013-03-21 18:02:36 +0400269 /*
270 * We get here in the unlikely case that a background
271 * request was allocated but not sent
272 */
273 spin_lock(&fc->lock);
274 if (!fc->blocked)
275 wake_up(&fc->blocked_waitq);
276 spin_unlock(&fc->lock);
277 }
278
Miklos Szeredi825d6d32015-07-01 16:25:58 +0200279 if (test_bit(FR_WAITING, &req->flags)) {
280 __clear_bit(FR_WAITING, &req->flags);
Miklos Szeredi9bc5ddd2006-04-11 21:16:09 +0200281 atomic_dec(&fc->num_waiting);
Miklos Szeredi73e0e732015-07-01 16:25:56 +0200282 }
Miklos Szeredi33649c92006-06-25 05:48:52 -0700283
284 if (req->stolen_file)
285 put_reserved_req(fc, req);
286 else
287 fuse_request_free(req);
Miklos Szeredi7128ec22006-02-04 23:27:40 -0800288 }
289}
Tejun Heo08cbf542009-04-14 10:54:53 +0900290EXPORT_SYMBOL_GPL(fuse_put_request);
Miklos Szeredi7128ec22006-02-04 23:27:40 -0800291
Miklos Szeredid12def12008-02-06 01:38:39 -0800292static unsigned len_args(unsigned numargs, struct fuse_arg *args)
293{
294 unsigned nbytes = 0;
295 unsigned i;
296
297 for (i = 0; i < numargs; i++)
298 nbytes += args[i].size;
299
300 return nbytes;
301}
302
Miklos Szeredif88996a2015-07-01 16:26:01 +0200303static u64 fuse_get_unique(struct fuse_iqueue *fiq)
Miklos Szeredid12def12008-02-06 01:38:39 -0800304{
Miklos Szeredif88996a2015-07-01 16:26:01 +0200305 return ++fiq->reqctr;
Miklos Szeredid12def12008-02-06 01:38:39 -0800306}
307
Miklos Szeredif88996a2015-07-01 16:26:01 +0200308static void queue_request(struct fuse_iqueue *fiq, struct fuse_req *req)
Miklos Szeredid12def12008-02-06 01:38:39 -0800309{
Miklos Szeredid12def12008-02-06 01:38:39 -0800310 req->in.h.len = sizeof(struct fuse_in_header) +
311 len_args(req->in.numargs, (struct fuse_arg *) req->in.args);
Miklos Szeredif88996a2015-07-01 16:26:01 +0200312 list_add_tail(&req->list, &fiq->pending);
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200313 wake_up_locked(&fiq->waitq);
Miklos Szeredif88996a2015-07-01 16:26:01 +0200314 kill_fasync(&fiq->fasync, SIGIO, POLL_IN);
Miklos Szeredid12def12008-02-06 01:38:39 -0800315}
316
Miklos Szeredi07e77dc2010-12-07 20:16:56 +0100317void fuse_queue_forget(struct fuse_conn *fc, struct fuse_forget_link *forget,
318 u64 nodeid, u64 nlookup)
319{
Miklos Szeredif88996a2015-07-01 16:26:01 +0200320 struct fuse_iqueue *fiq = &fc->iq;
321
Miklos Szeredi02c048b2010-12-07 20:16:56 +0100322 forget->forget_one.nodeid = nodeid;
323 forget->forget_one.nlookup = nlookup;
Miklos Szeredi07e77dc2010-12-07 20:16:56 +0100324
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200325 spin_lock(&fiq->waitq.lock);
Miklos Szeredie16714d2015-07-01 16:26:01 +0200326 if (fiq->connected) {
Miklos Szeredif88996a2015-07-01 16:26:01 +0200327 fiq->forget_list_tail->next = forget;
328 fiq->forget_list_tail = forget;
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200329 wake_up_locked(&fiq->waitq);
Miklos Szeredif88996a2015-07-01 16:26:01 +0200330 kill_fasync(&fiq->fasync, SIGIO, POLL_IN);
Miklos Szeredi5dfcc872011-09-12 09:38:03 +0200331 } else {
332 kfree(forget);
333 }
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200334 spin_unlock(&fiq->waitq.lock);
Miklos Szeredi07e77dc2010-12-07 20:16:56 +0100335}
336
Miklos Szeredid12def12008-02-06 01:38:39 -0800337static void flush_bg_queue(struct fuse_conn *fc)
338{
Csaba Henk7a6d3c82009-07-01 17:28:41 -0700339 while (fc->active_background < fc->max_background &&
Miklos Szeredid12def12008-02-06 01:38:39 -0800340 !list_empty(&fc->bg_queue)) {
341 struct fuse_req *req;
Miklos Szeredif88996a2015-07-01 16:26:01 +0200342 struct fuse_iqueue *fiq = &fc->iq;
Miklos Szeredid12def12008-02-06 01:38:39 -0800343
344 req = list_entry(fc->bg_queue.next, struct fuse_req, list);
345 list_del(&req->list);
346 fc->active_background++;
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200347 spin_lock(&fiq->waitq.lock);
Miklos Szeredif88996a2015-07-01 16:26:01 +0200348 req->in.h.unique = fuse_get_unique(fiq);
349 queue_request(fiq, req);
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200350 spin_unlock(&fiq->waitq.lock);
Miklos Szeredid12def12008-02-06 01:38:39 -0800351 }
352}
353
Miklos Szeredi6dbbcb12006-04-26 10:49:06 +0200354/*
Miklos Szeredi334f4852005-09-09 13:10:27 -0700355 * This function is called when a request is finished. Either a reply
Miklos Szeredif9a28422006-06-25 05:48:53 -0700356 * has arrived or it was aborted (and not yet sent) or some error
Miklos Szeredif43b1552006-01-16 22:14:26 -0800357 * occurred during communication with userspace, or the device file
Miklos Szeredi51eb01e2006-06-25 05:48:50 -0700358 * was closed. The requester thread is woken up (if still waiting),
359 * the 'end' callback is called if given, else the reference to the
360 * request is released
Miklos Szeredi334f4852005-09-09 13:10:27 -0700361 */
362static void request_end(struct fuse_conn *fc, struct fuse_req *req)
363{
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200364 struct fuse_iqueue *fiq = &fc->iq;
Miklos Szeredi365ae712015-07-01 16:26:06 +0200365
Miklos Szerediefe28002015-07-01 16:26:07 +0200366 if (test_and_set_bit(FR_FINISHED, &req->flags))
Miklos Szeredi365ae712015-07-01 16:26:06 +0200367 return;
Miklos Szeredi365ae712015-07-01 16:26:06 +0200368
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200369 spin_lock(&fiq->waitq.lock);
Miklos Szeredi0d8e84b2015-07-01 16:25:58 +0200370 list_del_init(&req->intr_entry);
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200371 spin_unlock(&fiq->waitq.lock);
Miklos Szeredi33e14b42015-07-01 16:26:01 +0200372 WARN_ON(test_bit(FR_PENDING, &req->flags));
373 WARN_ON(test_bit(FR_SENT, &req->flags));
Miklos Szeredi825d6d32015-07-01 16:25:58 +0200374 if (test_bit(FR_BACKGROUND, &req->flags)) {
Miklos Szerediefe28002015-07-01 16:26:07 +0200375 spin_lock(&fc->lock);
Miklos Szeredi825d6d32015-07-01 16:25:58 +0200376 clear_bit(FR_BACKGROUND, &req->flags);
Maxim Patlasov722d2be2013-03-21 18:02:36 +0400377 if (fc->num_background == fc->max_background)
Miklos Szeredi51eb01e2006-06-25 05:48:50 -0700378 fc->blocked = 0;
Maxim Patlasov722d2be2013-03-21 18:02:36 +0400379
380 /* Wake up next waiter, if any */
Miklos Szeredi3c18ef82013-04-17 21:50:58 +0200381 if (!fc->blocked && waitqueue_active(&fc->blocked_waitq))
Maxim Patlasov722d2be2013-03-21 18:02:36 +0400382 wake_up(&fc->blocked_waitq);
383
Csaba Henk7a6d3c82009-07-01 17:28:41 -0700384 if (fc->num_background == fc->congestion_threshold &&
Jan Kara7fbbe972017-04-12 12:24:41 +0200385 fc->connected && fc->sb) {
Jan Kara5f7f7542017-04-12 12:24:40 +0200386 clear_bdi_congested(fc->sb->s_bdi, BLK_RW_SYNC);
387 clear_bdi_congested(fc->sb->s_bdi, BLK_RW_ASYNC);
Miklos Szeredif92b99b2007-10-16 23:30:59 -0700388 }
Miklos Szeredi51eb01e2006-06-25 05:48:50 -0700389 fc->num_background--;
Miklos Szeredid12def12008-02-06 01:38:39 -0800390 fc->active_background--;
391 flush_bg_queue(fc);
Miklos Szerediefe28002015-07-01 16:26:07 +0200392 spin_unlock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700393 }
Miklos Szeredi51eb01e2006-06-25 05:48:50 -0700394 wake_up(&req->waitq);
Miklos Szeredi1e6881c2015-07-01 16:26:07 +0200395 if (req->end)
396 req->end(fc, req);
Tejun Heoe9bb09d2008-11-26 12:03:54 +0100397 fuse_put_request(fc, req);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700398}
399
Miklos Szeredif88996a2015-07-01 16:26:01 +0200400static void queue_interrupt(struct fuse_iqueue *fiq, struct fuse_req *req)
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700401{
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200402 spin_lock(&fiq->waitq.lock);
Sahitya Tummala6ba4d272017-02-08 20:30:56 +0530403 if (test_bit(FR_FINISHED, &req->flags)) {
404 spin_unlock(&fiq->waitq.lock);
405 return;
406 }
Miklos Szeredi8f7bb362015-07-01 16:26:03 +0200407 if (list_empty(&req->intr_entry)) {
408 list_add_tail(&req->intr_entry, &fiq->interrupts);
409 wake_up_locked(&fiq->waitq);
410 }
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200411 spin_unlock(&fiq->waitq.lock);
Miklos Szeredif88996a2015-07-01 16:26:01 +0200412 kill_fasync(&fiq->fasync, SIGIO, POLL_IN);
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700413}
414
Miklos Szeredi7c352bd2005-09-09 13:10:39 -0700415static void request_wait_answer(struct fuse_conn *fc, struct fuse_req *req)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700416{
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200417 struct fuse_iqueue *fiq = &fc->iq;
Miklos Szeredic4775262015-07-01 16:26:00 +0200418 int err;
419
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700420 if (!fc->no_interrupt) {
421 /* Any signal may interrupt this */
Miklos Szeredic4775262015-07-01 16:26:00 +0200422 err = wait_event_interruptible(req->waitq,
Miklos Szeredi33e14b42015-07-01 16:26:01 +0200423 test_bit(FR_FINISHED, &req->flags));
Miklos Szeredic4775262015-07-01 16:26:00 +0200424 if (!err)
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700425 return;
426
Miklos Szeredi825d6d32015-07-01 16:25:58 +0200427 set_bit(FR_INTERRUPTED, &req->flags);
Miklos Szeredi8f7bb362015-07-01 16:26:03 +0200428 /* matches barrier in fuse_dev_do_read() */
429 smp_mb__after_atomic();
Miklos Szeredi33e14b42015-07-01 16:26:01 +0200430 if (test_bit(FR_SENT, &req->flags))
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200431 queue_interrupt(fiq, req);
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700432 }
433
Miklos Szeredi825d6d32015-07-01 16:25:58 +0200434 if (!test_bit(FR_FORCE, &req->flags)) {
Miklos Szeredia4d27e72006-06-25 05:48:54 -0700435 /* Only fatal signals may interrupt this */
Al Viro7d3a07f2016-07-19 03:08:27 -0400436 err = wait_event_killable(req->waitq,
Miklos Szeredi33e14b42015-07-01 16:26:01 +0200437 test_bit(FR_FINISHED, &req->flags));
Miklos Szeredic4775262015-07-01 16:26:00 +0200438 if (!err)
Miklos Szeredia131de02007-10-16 23:31:04 -0700439 return;
440
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200441 spin_lock(&fiq->waitq.lock);
Miklos Szeredia131de02007-10-16 23:31:04 -0700442 /* Request is not yet in userspace, bail out */
Miklos Szeredi33e14b42015-07-01 16:26:01 +0200443 if (test_bit(FR_PENDING, &req->flags)) {
Miklos Szeredia131de02007-10-16 23:31:04 -0700444 list_del(&req->list);
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200445 spin_unlock(&fiq->waitq.lock);
Miklos Szeredia131de02007-10-16 23:31:04 -0700446 __fuse_put_request(req);
447 req->out.h.error = -EINTR;
448 return;
449 }
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200450 spin_unlock(&fiq->waitq.lock);
Miklos Szeredi51eb01e2006-06-25 05:48:50 -0700451 }
Miklos Szeredi334f4852005-09-09 13:10:27 -0700452
Miklos Szeredia131de02007-10-16 23:31:04 -0700453 /*
454 * Either request is already in userspace, or it was forced.
455 * Wait it out.
456 */
Miklos Szeredi33e14b42015-07-01 16:26:01 +0200457 wait_event(req->waitq, test_bit(FR_FINISHED, &req->flags));
Miklos Szeredi334f4852005-09-09 13:10:27 -0700458}
459
Eric Wong6a4e9222013-02-04 13:04:44 +0000460static void __fuse_request_send(struct fuse_conn *fc, struct fuse_req *req)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700461{
Miklos Szeredie16714d2015-07-01 16:26:01 +0200462 struct fuse_iqueue *fiq = &fc->iq;
463
Miklos Szeredi825d6d32015-07-01 16:25:58 +0200464 BUG_ON(test_bit(FR_BACKGROUND, &req->flags));
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200465 spin_lock(&fiq->waitq.lock);
Miklos Szeredie16714d2015-07-01 16:26:01 +0200466 if (!fiq->connected) {
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200467 spin_unlock(&fiq->waitq.lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700468 req->out.h.error = -ENOTCONN;
Miklos Szeredic4775262015-07-01 16:26:00 +0200469 } else {
Miklos Szeredif88996a2015-07-01 16:26:01 +0200470 req->in.h.unique = fuse_get_unique(fiq);
471 queue_request(fiq, req);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700472 /* acquire extra reference, since request is still needed
473 after request_end() */
474 __fuse_get_request(req);
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200475 spin_unlock(&fiq->waitq.lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700476
Miklos Szeredi7c352bd2005-09-09 13:10:39 -0700477 request_wait_answer(fc, req);
Miklos Szeredic4775262015-07-01 16:26:00 +0200478 /* Pairs with smp_wmb() in request_end() */
479 smp_rmb();
Miklos Szeredi334f4852005-09-09 13:10:27 -0700480 }
Miklos Szeredi334f4852005-09-09 13:10:27 -0700481}
Eric Wong6a4e9222013-02-04 13:04:44 +0000482
483void fuse_request_send(struct fuse_conn *fc, struct fuse_req *req)
484{
Miklos Szeredi825d6d32015-07-01 16:25:58 +0200485 __set_bit(FR_ISREPLY, &req->flags);
486 if (!test_bit(FR_WAITING, &req->flags)) {
487 __set_bit(FR_WAITING, &req->flags);
Miklos Szeredi5437f242015-07-01 16:25:56 +0200488 atomic_inc(&fc->num_waiting);
489 }
Eric Wong6a4e9222013-02-04 13:04:44 +0000490 __fuse_request_send(fc, req);
491}
Tejun Heo08cbf542009-04-14 10:54:53 +0900492EXPORT_SYMBOL_GPL(fuse_request_send);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700493
Miklos Szeredi21f62172015-01-06 10:45:35 +0100494static void fuse_adjust_compat(struct fuse_conn *fc, struct fuse_args *args)
495{
496 if (fc->minor < 4 && args->in.h.opcode == FUSE_STATFS)
497 args->out.args[0].size = FUSE_COMPAT_STATFS_SIZE;
498
499 if (fc->minor < 9) {
500 switch (args->in.h.opcode) {
501 case FUSE_LOOKUP:
502 case FUSE_CREATE:
503 case FUSE_MKNOD:
504 case FUSE_MKDIR:
505 case FUSE_SYMLINK:
506 case FUSE_LINK:
507 args->out.args[0].size = FUSE_COMPAT_ENTRY_OUT_SIZE;
508 break;
509 case FUSE_GETATTR:
510 case FUSE_SETATTR:
511 args->out.args[0].size = FUSE_COMPAT_ATTR_OUT_SIZE;
512 break;
513 }
514 }
515 if (fc->minor < 12) {
516 switch (args->in.h.opcode) {
517 case FUSE_CREATE:
518 args->in.args[0].size = sizeof(struct fuse_open_in);
519 break;
520 case FUSE_MKNOD:
521 args->in.args[0].size = FUSE_COMPAT_MKNOD_IN_SIZE;
522 break;
523 }
524 }
525}
526
Miklos Szeredi70781872014-12-12 09:49:05 +0100527ssize_t fuse_simple_request(struct fuse_conn *fc, struct fuse_args *args)
528{
529 struct fuse_req *req;
530 ssize_t ret;
531
532 req = fuse_get_req(fc, 0);
533 if (IS_ERR(req))
534 return PTR_ERR(req);
535
Miklos Szeredi21f62172015-01-06 10:45:35 +0100536 /* Needs to be done after fuse_get_req() so that fc->minor is valid */
537 fuse_adjust_compat(fc, args);
538
Miklos Szeredi70781872014-12-12 09:49:05 +0100539 req->in.h.opcode = args->in.h.opcode;
540 req->in.h.nodeid = args->in.h.nodeid;
541 req->in.numargs = args->in.numargs;
542 memcpy(req->in.args, args->in.args,
543 args->in.numargs * sizeof(struct fuse_in_arg));
544 req->out.argvar = args->out.argvar;
545 req->out.numargs = args->out.numargs;
546 memcpy(req->out.args, args->out.args,
547 args->out.numargs * sizeof(struct fuse_arg));
548 fuse_request_send(fc, req);
549 ret = req->out.h.error;
550 if (!ret && args->out.argvar) {
551 BUG_ON(args->out.numargs != 1);
552 ret = req->out.args[0].size;
553 }
554 fuse_put_request(fc, req);
555
556 return ret;
557}
558
Miklos Szeredif0139aa2015-07-01 16:25:57 +0200559/*
560 * Called under fc->lock
561 *
562 * fc->connected must have been checked previously
563 */
564void fuse_request_send_background_locked(struct fuse_conn *fc,
565 struct fuse_req *req)
Miklos Szeredid12def12008-02-06 01:38:39 -0800566{
Miklos Szeredi825d6d32015-07-01 16:25:58 +0200567 BUG_ON(!test_bit(FR_BACKGROUND, &req->flags));
568 if (!test_bit(FR_WAITING, &req->flags)) {
569 __set_bit(FR_WAITING, &req->flags);
Miklos Szeredi5437f242015-07-01 16:25:56 +0200570 atomic_inc(&fc->num_waiting);
571 }
Miklos Szeredi825d6d32015-07-01 16:25:58 +0200572 __set_bit(FR_ISREPLY, &req->flags);
Miklos Szeredid12def12008-02-06 01:38:39 -0800573 fc->num_background++;
Csaba Henk7a6d3c82009-07-01 17:28:41 -0700574 if (fc->num_background == fc->max_background)
Miklos Szeredid12def12008-02-06 01:38:39 -0800575 fc->blocked = 1;
Jan Kara7fbbe972017-04-12 12:24:41 +0200576 if (fc->num_background == fc->congestion_threshold && fc->sb) {
Jan Kara5f7f7542017-04-12 12:24:40 +0200577 set_bdi_congested(fc->sb->s_bdi, BLK_RW_SYNC);
578 set_bdi_congested(fc->sb->s_bdi, BLK_RW_ASYNC);
Miklos Szeredid12def12008-02-06 01:38:39 -0800579 }
580 list_add_tail(&req->list, &fc->bg_queue);
581 flush_bg_queue(fc);
582}
583
Miklos Szeredif0139aa2015-07-01 16:25:57 +0200584void fuse_request_send_background(struct fuse_conn *fc, struct fuse_req *req)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700585{
Miklos Szeredi42dc6212015-07-01 16:25:56 +0200586 BUG_ON(!req->end);
Miklos Szeredid7133112006-04-10 22:54:55 -0700587 spin_lock(&fc->lock);
Miklos Szeredi1e9a4ed2005-09-09 13:10:31 -0700588 if (fc->connected) {
Miklos Szeredif0139aa2015-07-01 16:25:57 +0200589 fuse_request_send_background_locked(fc, req);
Miklos Szeredid7133112006-04-10 22:54:55 -0700590 spin_unlock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700591 } else {
Miklos Szeredi42dc6212015-07-01 16:25:56 +0200592 spin_unlock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700593 req->out.h.error = -ENOTCONN;
Miklos Szeredi42dc6212015-07-01 16:25:56 +0200594 req->end(fc, req);
595 fuse_put_request(fc, req);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700596 }
597}
Tejun Heo08cbf542009-04-14 10:54:53 +0900598EXPORT_SYMBOL_GPL(fuse_request_send_background);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700599
Miklos Szeredi2d45ba32010-07-12 14:41:40 +0200600static int fuse_request_send_notify_reply(struct fuse_conn *fc,
601 struct fuse_req *req, u64 unique)
602{
603 int err = -ENODEV;
Miklos Szeredif88996a2015-07-01 16:26:01 +0200604 struct fuse_iqueue *fiq = &fc->iq;
Miklos Szeredi2d45ba32010-07-12 14:41:40 +0200605
Miklos Szeredi825d6d32015-07-01 16:25:58 +0200606 __clear_bit(FR_ISREPLY, &req->flags);
Miklos Szeredi2d45ba32010-07-12 14:41:40 +0200607 req->in.h.unique = unique;
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200608 spin_lock(&fiq->waitq.lock);
Miklos Szeredie16714d2015-07-01 16:26:01 +0200609 if (fiq->connected) {
Miklos Szeredif88996a2015-07-01 16:26:01 +0200610 queue_request(fiq, req);
Miklos Szeredi2d45ba32010-07-12 14:41:40 +0200611 err = 0;
612 }
Miklos Szeredi4ce60812015-07-01 16:26:02 +0200613 spin_unlock(&fiq->waitq.lock);
Miklos Szeredi2d45ba32010-07-12 14:41:40 +0200614
615 return err;
616}
617
Anand V. Avati0b05b182012-08-19 08:53:23 -0400618void fuse_force_forget(struct file *file, u64 nodeid)
619{
Al Viro6131ffa2013-02-27 16:59:05 -0500620 struct inode *inode = file_inode(file);
Anand V. Avati0b05b182012-08-19 08:53:23 -0400621 struct fuse_conn *fc = get_fuse_conn(inode);
622 struct fuse_req *req;
623 struct fuse_forget_in inarg;
624
625 memset(&inarg, 0, sizeof(inarg));
626 inarg.nlookup = 1;
Maxim Patlasovb111c8c2012-10-26 19:48:30 +0400627 req = fuse_get_req_nofail_nopages(fc, file);
Anand V. Avati0b05b182012-08-19 08:53:23 -0400628 req->in.h.opcode = FUSE_FORGET;
629 req->in.h.nodeid = nodeid;
630 req->in.numargs = 1;
631 req->in.args[0].size = sizeof(inarg);
632 req->in.args[0].value = &inarg;
Miklos Szeredi825d6d32015-07-01 16:25:58 +0200633 __clear_bit(FR_ISREPLY, &req->flags);
Eric Wong6a4e9222013-02-04 13:04:44 +0000634 __fuse_request_send(fc, req);
635 /* ignore errors */
636 fuse_put_request(fc, req);
Anand V. Avati0b05b182012-08-19 08:53:23 -0400637}
638
Miklos Szeredi3be5a522008-04-30 00:54:41 -0700639/*
Miklos Szeredi334f4852005-09-09 13:10:27 -0700640 * Lock the request. Up to the next unlock_request() there mustn't be
641 * anything that could cause a page-fault. If the request was already
Miklos Szeredif9a28422006-06-25 05:48:53 -0700642 * aborted bail out.
Miklos Szeredi334f4852005-09-09 13:10:27 -0700643 */
Miklos Szeredidc008092015-07-01 16:25:58 +0200644static int lock_request(struct fuse_req *req)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700645{
646 int err = 0;
647 if (req) {
Miklos Szeredidc008092015-07-01 16:25:58 +0200648 spin_lock(&req->waitq.lock);
Miklos Szeredi825d6d32015-07-01 16:25:58 +0200649 if (test_bit(FR_ABORTED, &req->flags))
Miklos Szeredi334f4852005-09-09 13:10:27 -0700650 err = -ENOENT;
651 else
Miklos Szeredi825d6d32015-07-01 16:25:58 +0200652 set_bit(FR_LOCKED, &req->flags);
Miklos Szeredidc008092015-07-01 16:25:58 +0200653 spin_unlock(&req->waitq.lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700654 }
655 return err;
656}
657
658/*
Miklos Szeredi0d8e84b2015-07-01 16:25:58 +0200659 * Unlock request. If it was aborted while locked, caller is responsible
660 * for unlocking and ending the request.
Miklos Szeredi334f4852005-09-09 13:10:27 -0700661 */
Miklos Szeredidc008092015-07-01 16:25:58 +0200662static int unlock_request(struct fuse_req *req)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700663{
Miklos Szeredi0d8e84b2015-07-01 16:25:58 +0200664 int err = 0;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700665 if (req) {
Miklos Szeredidc008092015-07-01 16:25:58 +0200666 spin_lock(&req->waitq.lock);
Miklos Szeredi825d6d32015-07-01 16:25:58 +0200667 if (test_bit(FR_ABORTED, &req->flags))
Miklos Szeredi0d8e84b2015-07-01 16:25:58 +0200668 err = -ENOENT;
669 else
Miklos Szeredi825d6d32015-07-01 16:25:58 +0200670 clear_bit(FR_LOCKED, &req->flags);
Miklos Szeredidc008092015-07-01 16:25:58 +0200671 spin_unlock(&req->waitq.lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700672 }
Miklos Szeredi0d8e84b2015-07-01 16:25:58 +0200673 return err;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700674}
675
676struct fuse_copy_state {
677 int write;
678 struct fuse_req *req;
Al Viro6c09e942015-04-03 22:06:08 -0400679 struct iov_iter *iter;
Miklos Szeredidd3bb142010-05-25 15:06:06 +0200680 struct pipe_buffer *pipebufs;
681 struct pipe_buffer *currbuf;
682 struct pipe_inode_info *pipe;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700683 unsigned long nr_segs;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700684 struct page *pg;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700685 unsigned len;
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200686 unsigned offset;
Miklos Szeredice534fb2010-05-25 15:06:07 +0200687 unsigned move_pages:1;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700688};
689
Miklos Szeredidc008092015-07-01 16:25:58 +0200690static void fuse_copy_init(struct fuse_copy_state *cs, int write,
Al Viro6c09e942015-04-03 22:06:08 -0400691 struct iov_iter *iter)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700692{
693 memset(cs, 0, sizeof(*cs));
694 cs->write = write;
Al Viro6c09e942015-04-03 22:06:08 -0400695 cs->iter = iter;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700696}
697
698/* Unmap and put previous page of userspace buffer */
Miklos Szeredi8bfc0162006-01-16 22:14:28 -0800699static void fuse_copy_finish(struct fuse_copy_state *cs)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700700{
Miklos Szeredidd3bb142010-05-25 15:06:06 +0200701 if (cs->currbuf) {
702 struct pipe_buffer *buf = cs->currbuf;
703
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200704 if (cs->write)
Miklos Szeredic3021622010-05-25 15:06:07 +0200705 buf->len = PAGE_SIZE - cs->len;
Miklos Szeredidd3bb142010-05-25 15:06:06 +0200706 cs->currbuf = NULL;
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200707 } else if (cs->pg) {
Miklos Szeredi334f4852005-09-09 13:10:27 -0700708 if (cs->write) {
709 flush_dcache_page(cs->pg);
710 set_page_dirty_lock(cs->pg);
711 }
712 put_page(cs->pg);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700713 }
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200714 cs->pg = NULL;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700715}
716
717/*
718 * Get another pagefull of userspace buffer, and map it to kernel
719 * address space, and lock request
720 */
721static int fuse_copy_fill(struct fuse_copy_state *cs)
722{
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200723 struct page *page;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700724 int err;
725
Miklos Szeredidc008092015-07-01 16:25:58 +0200726 err = unlock_request(cs->req);
Miklos Szeredi0d8e84b2015-07-01 16:25:58 +0200727 if (err)
728 return err;
729
Miklos Szeredi334f4852005-09-09 13:10:27 -0700730 fuse_copy_finish(cs);
Miklos Szeredidd3bb142010-05-25 15:06:06 +0200731 if (cs->pipebufs) {
732 struct pipe_buffer *buf = cs->pipebufs;
733
Miklos Szeredic3021622010-05-25 15:06:07 +0200734 if (!cs->write) {
Miklos Szeredifba597d2016-09-27 10:45:12 +0200735 err = pipe_buf_confirm(cs->pipe, buf);
Miklos Szeredic3021622010-05-25 15:06:07 +0200736 if (err)
737 return err;
Miklos Szeredidd3bb142010-05-25 15:06:06 +0200738
Miklos Szeredic3021622010-05-25 15:06:07 +0200739 BUG_ON(!cs->nr_segs);
740 cs->currbuf = buf;
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200741 cs->pg = buf->page;
742 cs->offset = buf->offset;
Miklos Szeredic3021622010-05-25 15:06:07 +0200743 cs->len = buf->len;
Miklos Szeredic3021622010-05-25 15:06:07 +0200744 cs->pipebufs++;
745 cs->nr_segs--;
746 } else {
Miklos Szeredic3021622010-05-25 15:06:07 +0200747 if (cs->nr_segs == cs->pipe->buffers)
748 return -EIO;
749
750 page = alloc_page(GFP_HIGHUSER);
751 if (!page)
752 return -ENOMEM;
753
754 buf->page = page;
755 buf->offset = 0;
756 buf->len = 0;
757
758 cs->currbuf = buf;
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200759 cs->pg = page;
760 cs->offset = 0;
Miklos Szeredic3021622010-05-25 15:06:07 +0200761 cs->len = PAGE_SIZE;
762 cs->pipebufs++;
763 cs->nr_segs++;
764 }
Miklos Szeredidd3bb142010-05-25 15:06:06 +0200765 } else {
Al Viro6c09e942015-04-03 22:06:08 -0400766 size_t off;
767 err = iov_iter_get_pages(cs->iter, &page, PAGE_SIZE, 1, &off);
Miklos Szeredidd3bb142010-05-25 15:06:06 +0200768 if (err < 0)
769 return err;
Al Viro6c09e942015-04-03 22:06:08 -0400770 BUG_ON(!err);
771 cs->len = err;
772 cs->offset = off;
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200773 cs->pg = page;
Al Viro6c09e942015-04-03 22:06:08 -0400774 iov_iter_advance(cs->iter, err);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700775 }
Miklos Szeredi334f4852005-09-09 13:10:27 -0700776
Miklos Szeredidc008092015-07-01 16:25:58 +0200777 return lock_request(cs->req);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700778}
779
780/* Do as much copy to/from userspace buffer as we can */
Miklos Szeredi8bfc0162006-01-16 22:14:28 -0800781static int fuse_copy_do(struct fuse_copy_state *cs, void **val, unsigned *size)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700782{
783 unsigned ncpy = min(*size, cs->len);
784 if (val) {
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200785 void *pgaddr = kmap_atomic(cs->pg);
786 void *buf = pgaddr + cs->offset;
787
Miklos Szeredi334f4852005-09-09 13:10:27 -0700788 if (cs->write)
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200789 memcpy(buf, *val, ncpy);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700790 else
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200791 memcpy(*val, buf, ncpy);
792
793 kunmap_atomic(pgaddr);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700794 *val += ncpy;
795 }
796 *size -= ncpy;
797 cs->len -= ncpy;
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200798 cs->offset += ncpy;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700799 return ncpy;
800}
801
Miklos Szeredice534fb2010-05-25 15:06:07 +0200802static int fuse_check_page(struct page *page)
803{
804 if (page_mapcount(page) ||
805 page->mapping != NULL ||
806 page_count(page) != 1 ||
807 (page->flags & PAGE_FLAGS_CHECK_AT_PREP &
808 ~(1 << PG_locked |
809 1 << PG_referenced |
810 1 << PG_uptodate |
811 1 << PG_lru |
812 1 << PG_active |
813 1 << PG_reclaim))) {
814 printk(KERN_WARNING "fuse: trying to steal weird page\n");
815 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);
816 return 1;
817 }
818 return 0;
819}
820
821static int fuse_try_move_page(struct fuse_copy_state *cs, struct page **pagep)
822{
823 int err;
824 struct page *oldpage = *pagep;
825 struct page *newpage;
826 struct pipe_buffer *buf = cs->pipebufs;
Miklos Szeredice534fb2010-05-25 15:06:07 +0200827
Miklos Szeredidc008092015-07-01 16:25:58 +0200828 err = unlock_request(cs->req);
Miklos Szeredi0d8e84b2015-07-01 16:25:58 +0200829 if (err)
830 return err;
831
Miklos Szeredice534fb2010-05-25 15:06:07 +0200832 fuse_copy_finish(cs);
833
Miklos Szeredifba597d2016-09-27 10:45:12 +0200834 err = pipe_buf_confirm(cs->pipe, buf);
Miklos Szeredice534fb2010-05-25 15:06:07 +0200835 if (err)
836 return err;
837
838 BUG_ON(!cs->nr_segs);
839 cs->currbuf = buf;
840 cs->len = buf->len;
841 cs->pipebufs++;
842 cs->nr_segs--;
843
844 if (cs->len != PAGE_SIZE)
845 goto out_fallback;
846
Miklos Szeredica76f5b2016-09-27 10:45:12 +0200847 if (pipe_buf_steal(cs->pipe, buf) != 0)
Miklos Szeredice534fb2010-05-25 15:06:07 +0200848 goto out_fallback;
849
850 newpage = buf->page;
851
Miklos Szerediaa991b32015-02-26 11:45:47 +0100852 if (!PageUptodate(newpage))
853 SetPageUptodate(newpage);
Miklos Szeredice534fb2010-05-25 15:06:07 +0200854
855 ClearPageMappedToDisk(newpage);
856
857 if (fuse_check_page(newpage) != 0)
858 goto out_fallback_unlock;
859
Miklos Szeredice534fb2010-05-25 15:06:07 +0200860 /*
861 * This is a new and locked page, it shouldn't be mapped or
862 * have any special flags on it
863 */
864 if (WARN_ON(page_mapped(oldpage)))
865 goto out_fallback_unlock;
866 if (WARN_ON(page_has_private(oldpage)))
867 goto out_fallback_unlock;
868 if (WARN_ON(PageDirty(oldpage) || PageWriteback(oldpage)))
869 goto out_fallback_unlock;
870 if (WARN_ON(PageMlocked(oldpage)))
871 goto out_fallback_unlock;
872
Miklos Szeredief6a3c62011-03-22 16:30:52 -0700873 err = replace_page_cache_page(oldpage, newpage, GFP_KERNEL);
Miklos Szeredice534fb2010-05-25 15:06:07 +0200874 if (err) {
Miklos Szeredief6a3c62011-03-22 16:30:52 -0700875 unlock_page(newpage);
876 return err;
Miklos Szeredice534fb2010-05-25 15:06:07 +0200877 }
Miklos Szeredief6a3c62011-03-22 16:30:52 -0700878
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +0300879 get_page(newpage);
Miklos Szeredice534fb2010-05-25 15:06:07 +0200880
881 if (!(buf->flags & PIPE_BUF_FLAG_LRU))
882 lru_cache_add_file(newpage);
883
884 err = 0;
Miklos Szeredidc008092015-07-01 16:25:58 +0200885 spin_lock(&cs->req->waitq.lock);
Miklos Szeredi825d6d32015-07-01 16:25:58 +0200886 if (test_bit(FR_ABORTED, &cs->req->flags))
Miklos Szeredice534fb2010-05-25 15:06:07 +0200887 err = -ENOENT;
888 else
889 *pagep = newpage;
Miklos Szeredidc008092015-07-01 16:25:58 +0200890 spin_unlock(&cs->req->waitq.lock);
Miklos Szeredice534fb2010-05-25 15:06:07 +0200891
892 if (err) {
893 unlock_page(newpage);
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +0300894 put_page(newpage);
Miklos Szeredice534fb2010-05-25 15:06:07 +0200895 return err;
896 }
897
898 unlock_page(oldpage);
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +0300899 put_page(oldpage);
Miklos Szeredice534fb2010-05-25 15:06:07 +0200900 cs->len = 0;
901
902 return 0;
903
904out_fallback_unlock:
905 unlock_page(newpage);
906out_fallback:
Miklos Szeredic55a01d2014-07-07 15:28:51 +0200907 cs->pg = buf->page;
908 cs->offset = buf->offset;
Miklos Szeredice534fb2010-05-25 15:06:07 +0200909
Miklos Szeredidc008092015-07-01 16:25:58 +0200910 err = lock_request(cs->req);
Miklos Szeredice534fb2010-05-25 15:06:07 +0200911 if (err)
912 return err;
913
914 return 1;
915}
916
Miklos Szeredic3021622010-05-25 15:06:07 +0200917static int fuse_ref_page(struct fuse_copy_state *cs, struct page *page,
918 unsigned offset, unsigned count)
919{
920 struct pipe_buffer *buf;
Miklos Szeredi0d8e84b2015-07-01 16:25:58 +0200921 int err;
Miklos Szeredic3021622010-05-25 15:06:07 +0200922
923 if (cs->nr_segs == cs->pipe->buffers)
924 return -EIO;
925
Miklos Szeredidc008092015-07-01 16:25:58 +0200926 err = unlock_request(cs->req);
Miklos Szeredi0d8e84b2015-07-01 16:25:58 +0200927 if (err)
928 return err;
929
Miklos Szeredic3021622010-05-25 15:06:07 +0200930 fuse_copy_finish(cs);
931
932 buf = cs->pipebufs;
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +0300933 get_page(page);
Miklos Szeredic3021622010-05-25 15:06:07 +0200934 buf->page = page;
935 buf->offset = offset;
936 buf->len = count;
937
938 cs->pipebufs++;
939 cs->nr_segs++;
940 cs->len = 0;
941
942 return 0;
943}
944
Miklos Szeredi334f4852005-09-09 13:10:27 -0700945/*
946 * Copy a page in the request to/from the userspace buffer. Must be
947 * done atomically
948 */
Miklos Szeredice534fb2010-05-25 15:06:07 +0200949static int fuse_copy_page(struct fuse_copy_state *cs, struct page **pagep,
Miklos Szeredi8bfc0162006-01-16 22:14:28 -0800950 unsigned offset, unsigned count, int zeroing)
Miklos Szeredi334f4852005-09-09 13:10:27 -0700951{
Miklos Szeredice534fb2010-05-25 15:06:07 +0200952 int err;
953 struct page *page = *pagep;
954
Miklos Szeredib6777c42010-10-26 14:22:27 -0700955 if (page && zeroing && count < PAGE_SIZE)
956 clear_highpage(page);
957
Miklos Szeredi334f4852005-09-09 13:10:27 -0700958 while (count) {
Miklos Szeredic3021622010-05-25 15:06:07 +0200959 if (cs->write && cs->pipebufs && page) {
960 return fuse_ref_page(cs, page, offset, count);
961 } else if (!cs->len) {
Miklos Szeredice534fb2010-05-25 15:06:07 +0200962 if (cs->move_pages && page &&
963 offset == 0 && count == PAGE_SIZE) {
964 err = fuse_try_move_page(cs, pagep);
965 if (err <= 0)
966 return err;
967 } else {
968 err = fuse_copy_fill(cs);
969 if (err)
970 return err;
971 }
Miklos Szeredi1729a162008-11-26 12:03:54 +0100972 }
Miklos Szeredi334f4852005-09-09 13:10:27 -0700973 if (page) {
Cong Wang2408f6e2011-11-25 23:14:30 +0800974 void *mapaddr = kmap_atomic(page);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700975 void *buf = mapaddr + offset;
976 offset += fuse_copy_do(cs, &buf, &count);
Cong Wang2408f6e2011-11-25 23:14:30 +0800977 kunmap_atomic(mapaddr);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700978 } else
979 offset += fuse_copy_do(cs, NULL, &count);
980 }
981 if (page && !cs->write)
982 flush_dcache_page(page);
983 return 0;
984}
985
986/* Copy pages in the request to/from userspace buffer */
987static int fuse_copy_pages(struct fuse_copy_state *cs, unsigned nbytes,
988 int zeroing)
989{
990 unsigned i;
991 struct fuse_req *req = cs->req;
Miklos Szeredi334f4852005-09-09 13:10:27 -0700992
993 for (i = 0; i < req->num_pages && (nbytes || zeroing); i++) {
Miklos Szeredice534fb2010-05-25 15:06:07 +0200994 int err;
Maxim Patlasov85f40ae2012-10-26 19:49:33 +0400995 unsigned offset = req->page_descs[i].offset;
996 unsigned count = min(nbytes, req->page_descs[i].length);
Miklos Szeredice534fb2010-05-25 15:06:07 +0200997
998 err = fuse_copy_page(cs, &req->pages[i], offset, count,
999 zeroing);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001000 if (err)
1001 return err;
1002
1003 nbytes -= count;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001004 }
1005 return 0;
1006}
1007
1008/* Copy a single argument in the request to/from userspace buffer */
1009static int fuse_copy_one(struct fuse_copy_state *cs, void *val, unsigned size)
1010{
1011 while (size) {
Miklos Szeredi1729a162008-11-26 12:03:54 +01001012 if (!cs->len) {
1013 int err = fuse_copy_fill(cs);
1014 if (err)
1015 return err;
1016 }
Miklos Szeredi334f4852005-09-09 13:10:27 -07001017 fuse_copy_do(cs, &val, &size);
1018 }
1019 return 0;
1020}
1021
1022/* Copy request arguments to/from userspace buffer */
1023static int fuse_copy_args(struct fuse_copy_state *cs, unsigned numargs,
1024 unsigned argpages, struct fuse_arg *args,
1025 int zeroing)
1026{
1027 int err = 0;
1028 unsigned i;
1029
1030 for (i = 0; !err && i < numargs; i++) {
1031 struct fuse_arg *arg = &args[i];
1032 if (i == numargs - 1 && argpages)
1033 err = fuse_copy_pages(cs, arg->size, zeroing);
1034 else
1035 err = fuse_copy_one(cs, arg->value, arg->size);
1036 }
1037 return err;
1038}
1039
Miklos Szeredif88996a2015-07-01 16:26:01 +02001040static int forget_pending(struct fuse_iqueue *fiq)
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001041{
Miklos Szeredif88996a2015-07-01 16:26:01 +02001042 return fiq->forget_list_head.next != NULL;
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001043}
1044
Miklos Szeredif88996a2015-07-01 16:26:01 +02001045static int request_pending(struct fuse_iqueue *fiq)
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001046{
Miklos Szeredif88996a2015-07-01 16:26:01 +02001047 return !list_empty(&fiq->pending) || !list_empty(&fiq->interrupts) ||
1048 forget_pending(fiq);
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001049}
1050
Miklos Szeredi334f4852005-09-09 13:10:27 -07001051/*
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001052 * Transfer an interrupt request to userspace
1053 *
1054 * Unlike other requests this is assembled on demand, without a need
1055 * to allocate a separate fuse_req structure.
1056 *
Miklos Szeredifd22d622015-07-01 16:26:03 +02001057 * Called with fiq->waitq.lock held, releases it
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001058 */
Miklos Szeredifd22d622015-07-01 16:26:03 +02001059static int fuse_read_interrupt(struct fuse_iqueue *fiq,
1060 struct fuse_copy_state *cs,
Miklos Szeredic3021622010-05-25 15:06:07 +02001061 size_t nbytes, struct fuse_req *req)
Miklos Szeredifd22d622015-07-01 16:26:03 +02001062__releases(fiq->waitq.lock)
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001063{
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001064 struct fuse_in_header ih;
1065 struct fuse_interrupt_in arg;
1066 unsigned reqsize = sizeof(ih) + sizeof(arg);
1067 int err;
1068
1069 list_del_init(&req->intr_entry);
Miklos Szeredi4ce60812015-07-01 16:26:02 +02001070 req->intr_unique = fuse_get_unique(fiq);
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001071 memset(&ih, 0, sizeof(ih));
1072 memset(&arg, 0, sizeof(arg));
1073 ih.len = reqsize;
1074 ih.opcode = FUSE_INTERRUPT;
1075 ih.unique = req->intr_unique;
1076 arg.unique = req->in.h.unique;
1077
Miklos Szeredi4ce60812015-07-01 16:26:02 +02001078 spin_unlock(&fiq->waitq.lock);
Miklos Szeredic3021622010-05-25 15:06:07 +02001079 if (nbytes < reqsize)
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001080 return -EINVAL;
1081
Miklos Szeredic3021622010-05-25 15:06:07 +02001082 err = fuse_copy_one(cs, &ih, sizeof(ih));
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001083 if (!err)
Miklos Szeredic3021622010-05-25 15:06:07 +02001084 err = fuse_copy_one(cs, &arg, sizeof(arg));
1085 fuse_copy_finish(cs);
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001086
1087 return err ? err : reqsize;
1088}
1089
Miklos Szeredif88996a2015-07-01 16:26:01 +02001090static struct fuse_forget_link *dequeue_forget(struct fuse_iqueue *fiq,
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001091 unsigned max,
1092 unsigned *countp)
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001093{
Miklos Szeredif88996a2015-07-01 16:26:01 +02001094 struct fuse_forget_link *head = fiq->forget_list_head.next;
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001095 struct fuse_forget_link **newhead = &head;
1096 unsigned count;
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001097
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001098 for (count = 0; *newhead != NULL && count < max; count++)
1099 newhead = &(*newhead)->next;
1100
Miklos Szeredif88996a2015-07-01 16:26:01 +02001101 fiq->forget_list_head.next = *newhead;
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001102 *newhead = NULL;
Miklos Szeredif88996a2015-07-01 16:26:01 +02001103 if (fiq->forget_list_head.next == NULL)
1104 fiq->forget_list_tail = &fiq->forget_list_head;
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001105
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001106 if (countp != NULL)
1107 *countp = count;
1108
1109 return head;
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001110}
1111
Miklos Szeredifd22d622015-07-01 16:26:03 +02001112static int fuse_read_single_forget(struct fuse_iqueue *fiq,
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001113 struct fuse_copy_state *cs,
1114 size_t nbytes)
Miklos Szeredifd22d622015-07-01 16:26:03 +02001115__releases(fiq->waitq.lock)
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001116{
1117 int err;
Miklos Szeredif88996a2015-07-01 16:26:01 +02001118 struct fuse_forget_link *forget = dequeue_forget(fiq, 1, NULL);
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001119 struct fuse_forget_in arg = {
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001120 .nlookup = forget->forget_one.nlookup,
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001121 };
1122 struct fuse_in_header ih = {
1123 .opcode = FUSE_FORGET,
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001124 .nodeid = forget->forget_one.nodeid,
Miklos Szeredif88996a2015-07-01 16:26:01 +02001125 .unique = fuse_get_unique(fiq),
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001126 .len = sizeof(ih) + sizeof(arg),
1127 };
1128
Miklos Szeredi4ce60812015-07-01 16:26:02 +02001129 spin_unlock(&fiq->waitq.lock);
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001130 kfree(forget);
1131 if (nbytes < ih.len)
1132 return -EINVAL;
1133
1134 err = fuse_copy_one(cs, &ih, sizeof(ih));
1135 if (!err)
1136 err = fuse_copy_one(cs, &arg, sizeof(arg));
1137 fuse_copy_finish(cs);
1138
1139 if (err)
1140 return err;
1141
1142 return ih.len;
1143}
1144
Miklos Szeredifd22d622015-07-01 16:26:03 +02001145static int fuse_read_batch_forget(struct fuse_iqueue *fiq,
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001146 struct fuse_copy_state *cs, size_t nbytes)
Miklos Szeredifd22d622015-07-01 16:26:03 +02001147__releases(fiq->waitq.lock)
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001148{
1149 int err;
1150 unsigned max_forgets;
1151 unsigned count;
1152 struct fuse_forget_link *head;
1153 struct fuse_batch_forget_in arg = { .count = 0 };
1154 struct fuse_in_header ih = {
1155 .opcode = FUSE_BATCH_FORGET,
Miklos Szeredif88996a2015-07-01 16:26:01 +02001156 .unique = fuse_get_unique(fiq),
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001157 .len = sizeof(ih) + sizeof(arg),
1158 };
1159
1160 if (nbytes < ih.len) {
Miklos Szeredi4ce60812015-07-01 16:26:02 +02001161 spin_unlock(&fiq->waitq.lock);
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001162 return -EINVAL;
1163 }
1164
1165 max_forgets = (nbytes - ih.len) / sizeof(struct fuse_forget_one);
Miklos Szeredif88996a2015-07-01 16:26:01 +02001166 head = dequeue_forget(fiq, max_forgets, &count);
Miklos Szeredi4ce60812015-07-01 16:26:02 +02001167 spin_unlock(&fiq->waitq.lock);
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001168
1169 arg.count = count;
1170 ih.len += count * sizeof(struct fuse_forget_one);
1171 err = fuse_copy_one(cs, &ih, sizeof(ih));
1172 if (!err)
1173 err = fuse_copy_one(cs, &arg, sizeof(arg));
1174
1175 while (head) {
1176 struct fuse_forget_link *forget = head;
1177
1178 if (!err) {
1179 err = fuse_copy_one(cs, &forget->forget_one,
1180 sizeof(forget->forget_one));
1181 }
1182 head = forget->next;
1183 kfree(forget);
1184 }
1185
1186 fuse_copy_finish(cs);
1187
1188 if (err)
1189 return err;
1190
1191 return ih.len;
1192}
1193
Miklos Szeredifd22d622015-07-01 16:26:03 +02001194static int fuse_read_forget(struct fuse_conn *fc, struct fuse_iqueue *fiq,
1195 struct fuse_copy_state *cs,
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001196 size_t nbytes)
Miklos Szeredifd22d622015-07-01 16:26:03 +02001197__releases(fiq->waitq.lock)
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001198{
Miklos Szeredif88996a2015-07-01 16:26:01 +02001199 if (fc->minor < 16 || fiq->forget_list_head.next->next == NULL)
Miklos Szeredifd22d622015-07-01 16:26:03 +02001200 return fuse_read_single_forget(fiq, cs, nbytes);
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001201 else
Miklos Szeredifd22d622015-07-01 16:26:03 +02001202 return fuse_read_batch_forget(fiq, cs, nbytes);
Miklos Szeredi02c048b2010-12-07 20:16:56 +01001203}
1204
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001205/*
Miklos Szeredi334f4852005-09-09 13:10:27 -07001206 * Read a single request into the userspace filesystem's buffer. This
1207 * function waits until a request is available, then removes it from
1208 * the pending list and copies request data to userspace buffer. If
Miklos Szeredif9a28422006-06-25 05:48:53 -07001209 * no reply is needed (FORGET) or request has been aborted or there
1210 * was an error during the copying then it's finished by calling
Miklos Szeredi334f4852005-09-09 13:10:27 -07001211 * request_end(). Otherwise add it to the processing list, and set
1212 * the 'sent' flag.
1213 */
Miklos Szeredic36960462015-07-01 16:26:09 +02001214static ssize_t fuse_dev_do_read(struct fuse_dev *fud, struct file *file,
Miklos Szeredic3021622010-05-25 15:06:07 +02001215 struct fuse_copy_state *cs, size_t nbytes)
Miklos Szeredi334f4852005-09-09 13:10:27 -07001216{
Miklos Szeredi82cbdcd2015-07-01 16:26:05 +02001217 ssize_t err;
Miklos Szeredic36960462015-07-01 16:26:09 +02001218 struct fuse_conn *fc = fud->fc;
Miklos Szeredif88996a2015-07-01 16:26:01 +02001219 struct fuse_iqueue *fiq = &fc->iq;
Miklos Szeredic36960462015-07-01 16:26:09 +02001220 struct fuse_pqueue *fpq = &fud->pq;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001221 struct fuse_req *req;
1222 struct fuse_in *in;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001223 unsigned reqsize;
1224
Miklos Szeredi1d3d7522006-01-06 00:19:40 -08001225 restart:
Miklos Szeredi4ce60812015-07-01 16:26:02 +02001226 spin_lock(&fiq->waitq.lock);
Jeff Dikee5ac1d12006-04-10 22:54:53 -07001227 err = -EAGAIN;
Miklos Szeredie16714d2015-07-01 16:26:01 +02001228 if ((file->f_flags & O_NONBLOCK) && fiq->connected &&
Miklos Szeredif88996a2015-07-01 16:26:01 +02001229 !request_pending(fiq))
Jeff Dikee5ac1d12006-04-10 22:54:53 -07001230 goto err_unlock;
1231
Miklos Szeredi52509212015-07-01 16:26:03 +02001232 err = wait_event_interruptible_exclusive_locked(fiq->waitq,
1233 !fiq->connected || request_pending(fiq));
1234 if (err)
1235 goto err_unlock;
1236
Miklos Szeredi334f4852005-09-09 13:10:27 -07001237 err = -ENODEV;
Miklos Szeredie16714d2015-07-01 16:26:01 +02001238 if (!fiq->connected)
Miklos Szeredi334f4852005-09-09 13:10:27 -07001239 goto err_unlock;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001240
Miklos Szeredif88996a2015-07-01 16:26:01 +02001241 if (!list_empty(&fiq->interrupts)) {
1242 req = list_entry(fiq->interrupts.next, struct fuse_req,
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001243 intr_entry);
Miklos Szeredifd22d622015-07-01 16:26:03 +02001244 return fuse_read_interrupt(fiq, cs, nbytes, req);
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001245 }
1246
Miklos Szeredif88996a2015-07-01 16:26:01 +02001247 if (forget_pending(fiq)) {
1248 if (list_empty(&fiq->pending) || fiq->forget_batch-- > 0)
Miklos Szeredifd22d622015-07-01 16:26:03 +02001249 return fuse_read_forget(fc, fiq, cs, nbytes);
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001250
Miklos Szeredif88996a2015-07-01 16:26:01 +02001251 if (fiq->forget_batch <= -8)
1252 fiq->forget_batch = 16;
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001253 }
1254
Miklos Szeredif88996a2015-07-01 16:26:01 +02001255 req = list_entry(fiq->pending.next, struct fuse_req, list);
Miklos Szeredi33e14b42015-07-01 16:26:01 +02001256 clear_bit(FR_PENDING, &req->flags);
Miklos Szeredief759252015-07-01 16:26:02 +02001257 list_del_init(&req->list);
Miklos Szeredi4ce60812015-07-01 16:26:02 +02001258 spin_unlock(&fiq->waitq.lock);
1259
Miklos Szeredi334f4852005-09-09 13:10:27 -07001260 in = &req->in;
Miklos Szeredi1d3d7522006-01-06 00:19:40 -08001261 reqsize = in->h.len;
Miklos Szeredi5d6d3a32017-09-12 16:57:53 +02001262
1263 if (task_active_pid_ns(current) != fc->pid_ns) {
1264 rcu_read_lock();
1265 in->h.pid = pid_vnr(find_pid_ns(in->h.pid, fc->pid_ns));
1266 rcu_read_unlock();
1267 }
1268
Miklos Szeredi1d3d7522006-01-06 00:19:40 -08001269 /* If request is too large, reply with an error and restart the read */
Miklos Szeredic3021622010-05-25 15:06:07 +02001270 if (nbytes < reqsize) {
Miklos Szeredi1d3d7522006-01-06 00:19:40 -08001271 req->out.h.error = -EIO;
1272 /* SETXATTR is special, since it may contain too large data */
1273 if (in->h.opcode == FUSE_SETXATTR)
1274 req->out.h.error = -E2BIG;
1275 request_end(fc, req);
1276 goto restart;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001277 }
Miklos Szeredi45a91cb2015-07-01 16:26:06 +02001278 spin_lock(&fpq->lock);
Miklos Szeredi82cbdcd2015-07-01 16:26:05 +02001279 list_add(&req->list, &fpq->io);
Miklos Szeredi45a91cb2015-07-01 16:26:06 +02001280 spin_unlock(&fpq->lock);
Miklos Szeredic3021622010-05-25 15:06:07 +02001281 cs->req = req;
1282 err = fuse_copy_one(cs, &in->h, sizeof(in->h));
Miklos Szeredi1d3d7522006-01-06 00:19:40 -08001283 if (!err)
Miklos Szeredic3021622010-05-25 15:06:07 +02001284 err = fuse_copy_args(cs, in->numargs, in->argpages,
Miklos Szeredi1d3d7522006-01-06 00:19:40 -08001285 (struct fuse_arg *) in->args, 0);
Miklos Szeredic3021622010-05-25 15:06:07 +02001286 fuse_copy_finish(cs);
Miklos Szeredi45a91cb2015-07-01 16:26:06 +02001287 spin_lock(&fpq->lock);
Miklos Szeredi825d6d32015-07-01 16:25:58 +02001288 clear_bit(FR_LOCKED, &req->flags);
Miklos Szeredie96edd92015-07-01 16:26:04 +02001289 if (!fpq->connected) {
Miklos Szeredi82cbdcd2015-07-01 16:26:05 +02001290 err = -ENODEV;
1291 goto out_end;
Miklos Szeredic9c9d7d2007-10-16 23:31:05 -07001292 }
Miklos Szeredi334f4852005-09-09 13:10:27 -07001293 if (err) {
Miklos Szeredic9c9d7d2007-10-16 23:31:05 -07001294 req->out.h.error = -EIO;
Miklos Szeredi82cbdcd2015-07-01 16:26:05 +02001295 goto out_end;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001296 }
Miklos Szeredi825d6d32015-07-01 16:25:58 +02001297 if (!test_bit(FR_ISREPLY, &req->flags)) {
Miklos Szeredi82cbdcd2015-07-01 16:26:05 +02001298 err = reqsize;
1299 goto out_end;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001300 }
Miklos Szeredi82cbdcd2015-07-01 16:26:05 +02001301 list_move_tail(&req->list, &fpq->processing);
Miklos Szeredi45a91cb2015-07-01 16:26:06 +02001302 spin_unlock(&fpq->lock);
Miklos Szeredi82cbdcd2015-07-01 16:26:05 +02001303 set_bit(FR_SENT, &req->flags);
1304 /* matches barrier in request_wait_answer() */
1305 smp_mb__after_atomic();
1306 if (test_bit(FR_INTERRUPTED, &req->flags))
1307 queue_interrupt(fiq, req);
Miklos Szeredi82cbdcd2015-07-01 16:26:05 +02001308
Miklos Szeredi334f4852005-09-09 13:10:27 -07001309 return reqsize;
1310
Miklos Szeredi82cbdcd2015-07-01 16:26:05 +02001311out_end:
Miklos Szeredi77cd9d42015-07-01 16:26:06 +02001312 if (!test_bit(FR_PRIVATE, &req->flags))
1313 list_del_init(&req->list);
Miklos Szeredi45a91cb2015-07-01 16:26:06 +02001314 spin_unlock(&fpq->lock);
Miklos Szeredi82cbdcd2015-07-01 16:26:05 +02001315 request_end(fc, req);
1316 return err;
1317
Miklos Szeredi334f4852005-09-09 13:10:27 -07001318 err_unlock:
Miklos Szeredi4ce60812015-07-01 16:26:02 +02001319 spin_unlock(&fiq->waitq.lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001320 return err;
1321}
1322
Tom Van Braeckel94e4fe22015-01-12 05:22:16 +01001323static int fuse_dev_open(struct inode *inode, struct file *file)
1324{
1325 /*
1326 * The fuse device's file's private_data is used to hold
1327 * the fuse_conn(ection) when it is mounted, and is used to
1328 * keep track of whether the file has been mounted already.
1329 */
1330 file->private_data = NULL;
1331 return 0;
1332}
1333
Al Virofbdbacc2015-04-03 21:53:39 -04001334static ssize_t fuse_dev_read(struct kiocb *iocb, struct iov_iter *to)
Miklos Szeredic3021622010-05-25 15:06:07 +02001335{
1336 struct fuse_copy_state cs;
1337 struct file *file = iocb->ki_filp;
Miklos Szeredicc080e92015-07-01 16:26:08 +02001338 struct fuse_dev *fud = fuse_get_dev(file);
1339
1340 if (!fud)
Miklos Szeredic3021622010-05-25 15:06:07 +02001341 return -EPERM;
1342
Al Virofbdbacc2015-04-03 21:53:39 -04001343 if (!iter_is_iovec(to))
1344 return -EINVAL;
Miklos Szeredic3021622010-05-25 15:06:07 +02001345
Miklos Szeredidc008092015-07-01 16:25:58 +02001346 fuse_copy_init(&cs, 1, to);
Al Virofbdbacc2015-04-03 21:53:39 -04001347
Miklos Szeredic36960462015-07-01 16:26:09 +02001348 return fuse_dev_do_read(fud, file, &cs, iov_iter_count(to));
Miklos Szeredic3021622010-05-25 15:06:07 +02001349}
1350
Miklos Szeredic3021622010-05-25 15:06:07 +02001351static ssize_t fuse_dev_splice_read(struct file *in, loff_t *ppos,
1352 struct pipe_inode_info *pipe,
1353 size_t len, unsigned int flags)
1354{
Al Virod82718e2016-09-17 22:56:25 -04001355 int total, ret;
Miklos Szeredic3021622010-05-25 15:06:07 +02001356 int page_nr = 0;
Miklos Szeredic3021622010-05-25 15:06:07 +02001357 struct pipe_buffer *bufs;
1358 struct fuse_copy_state cs;
Miklos Szeredicc080e92015-07-01 16:26:08 +02001359 struct fuse_dev *fud = fuse_get_dev(in);
1360
1361 if (!fud)
Miklos Szeredic3021622010-05-25 15:06:07 +02001362 return -EPERM;
1363
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001364 bufs = kmalloc(pipe->buffers * sizeof(struct pipe_buffer), GFP_KERNEL);
Miklos Szeredic3021622010-05-25 15:06:07 +02001365 if (!bufs)
1366 return -ENOMEM;
1367
Miklos Szeredidc008092015-07-01 16:25:58 +02001368 fuse_copy_init(&cs, 1, NULL);
Miklos Szeredic3021622010-05-25 15:06:07 +02001369 cs.pipebufs = bufs;
1370 cs.pipe = pipe;
Miklos Szeredic36960462015-07-01 16:26:09 +02001371 ret = fuse_dev_do_read(fud, in, &cs, len);
Miklos Szeredic3021622010-05-25 15:06:07 +02001372 if (ret < 0)
1373 goto out;
1374
Miklos Szeredic3021622010-05-25 15:06:07 +02001375 if (pipe->nrbufs + cs.nr_segs > pipe->buffers) {
1376 ret = -EIO;
Al Virod82718e2016-09-17 22:56:25 -04001377 goto out;
Miklos Szeredic3021622010-05-25 15:06:07 +02001378 }
1379
Al Virod82718e2016-09-17 22:56:25 -04001380 for (ret = total = 0; page_nr < cs.nr_segs; total += ret) {
Miklos Szeredi28a625c2014-01-22 19:36:57 +01001381 /*
1382 * Need to be careful about this. Having buf->ops in module
1383 * code can Oops if the buffer persists after module unload.
1384 */
Al Virod82718e2016-09-17 22:56:25 -04001385 bufs[page_nr].ops = &nosteal_pipe_buf_ops;
Miklos Szeredi84588a92017-02-16 15:08:20 +01001386 bufs[page_nr].flags = 0;
Al Virod82718e2016-09-17 22:56:25 -04001387 ret = add_to_pipe(pipe, &bufs[page_nr++]);
1388 if (unlikely(ret < 0))
1389 break;
Miklos Szeredic3021622010-05-25 15:06:07 +02001390 }
Al Virod82718e2016-09-17 22:56:25 -04001391 if (total)
1392 ret = total;
Miklos Szeredic3021622010-05-25 15:06:07 +02001393out:
1394 for (; page_nr < cs.nr_segs; page_nr++)
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +03001395 put_page(bufs[page_nr].page);
Miklos Szeredic3021622010-05-25 15:06:07 +02001396
1397 kfree(bufs);
1398 return ret;
1399}
1400
Tejun Heo95668a62008-11-26 12:03:55 +01001401static int fuse_notify_poll(struct fuse_conn *fc, unsigned int size,
1402 struct fuse_copy_state *cs)
1403{
1404 struct fuse_notify_poll_wakeup_out outarg;
Miklos Szeredif6d47a12009-01-26 15:00:59 +01001405 int err = -EINVAL;
Tejun Heo95668a62008-11-26 12:03:55 +01001406
1407 if (size != sizeof(outarg))
Miklos Szeredif6d47a12009-01-26 15:00:59 +01001408 goto err;
Tejun Heo95668a62008-11-26 12:03:55 +01001409
1410 err = fuse_copy_one(cs, &outarg, sizeof(outarg));
1411 if (err)
Miklos Szeredif6d47a12009-01-26 15:00:59 +01001412 goto err;
Tejun Heo95668a62008-11-26 12:03:55 +01001413
Miklos Szeredif6d47a12009-01-26 15:00:59 +01001414 fuse_copy_finish(cs);
Tejun Heo95668a62008-11-26 12:03:55 +01001415 return fuse_notify_poll_wakeup(fc, &outarg);
Miklos Szeredif6d47a12009-01-26 15:00:59 +01001416
1417err:
1418 fuse_copy_finish(cs);
1419 return err;
Tejun Heo95668a62008-11-26 12:03:55 +01001420}
1421
John Muir3b463ae2009-05-31 11:13:57 -04001422static int fuse_notify_inval_inode(struct fuse_conn *fc, unsigned int size,
1423 struct fuse_copy_state *cs)
1424{
1425 struct fuse_notify_inval_inode_out outarg;
1426 int err = -EINVAL;
1427
1428 if (size != sizeof(outarg))
1429 goto err;
1430
1431 err = fuse_copy_one(cs, &outarg, sizeof(outarg));
1432 if (err)
1433 goto err;
1434 fuse_copy_finish(cs);
1435
1436 down_read(&fc->killsb);
1437 err = -ENOENT;
Miklos Szeredib21dda42010-02-05 12:08:31 +01001438 if (fc->sb) {
1439 err = fuse_reverse_inval_inode(fc->sb, outarg.ino,
1440 outarg.off, outarg.len);
1441 }
John Muir3b463ae2009-05-31 11:13:57 -04001442 up_read(&fc->killsb);
1443 return err;
1444
1445err:
1446 fuse_copy_finish(cs);
1447 return err;
1448}
1449
1450static int fuse_notify_inval_entry(struct fuse_conn *fc, unsigned int size,
1451 struct fuse_copy_state *cs)
1452{
1453 struct fuse_notify_inval_entry_out outarg;
Fang Wenqib2d82ee2009-12-30 18:37:13 +08001454 int err = -ENOMEM;
1455 char *buf;
John Muir3b463ae2009-05-31 11:13:57 -04001456 struct qstr name;
1457
Fang Wenqib2d82ee2009-12-30 18:37:13 +08001458 buf = kzalloc(FUSE_NAME_MAX + 1, GFP_KERNEL);
1459 if (!buf)
1460 goto err;
1461
1462 err = -EINVAL;
John Muir3b463ae2009-05-31 11:13:57 -04001463 if (size < sizeof(outarg))
1464 goto err;
1465
1466 err = fuse_copy_one(cs, &outarg, sizeof(outarg));
1467 if (err)
1468 goto err;
1469
1470 err = -ENAMETOOLONG;
1471 if (outarg.namelen > FUSE_NAME_MAX)
1472 goto err;
1473
Miklos Szeredic2183d12011-08-24 10:20:17 +02001474 err = -EINVAL;
1475 if (size != sizeof(outarg) + outarg.namelen + 1)
1476 goto err;
1477
John Muir3b463ae2009-05-31 11:13:57 -04001478 name.name = buf;
1479 name.len = outarg.namelen;
1480 err = fuse_copy_one(cs, buf, outarg.namelen + 1);
1481 if (err)
1482 goto err;
1483 fuse_copy_finish(cs);
1484 buf[outarg.namelen] = 0;
John Muir3b463ae2009-05-31 11:13:57 -04001485
1486 down_read(&fc->killsb);
1487 err = -ENOENT;
Miklos Szeredib21dda42010-02-05 12:08:31 +01001488 if (fc->sb)
John Muir451d0f52011-12-06 21:50:06 +01001489 err = fuse_reverse_inval_entry(fc->sb, outarg.parent, 0, &name);
1490 up_read(&fc->killsb);
1491 kfree(buf);
1492 return err;
1493
1494err:
1495 kfree(buf);
1496 fuse_copy_finish(cs);
1497 return err;
1498}
1499
1500static int fuse_notify_delete(struct fuse_conn *fc, unsigned int size,
1501 struct fuse_copy_state *cs)
1502{
1503 struct fuse_notify_delete_out outarg;
1504 int err = -ENOMEM;
1505 char *buf;
1506 struct qstr name;
1507
1508 buf = kzalloc(FUSE_NAME_MAX + 1, GFP_KERNEL);
1509 if (!buf)
1510 goto err;
1511
1512 err = -EINVAL;
1513 if (size < sizeof(outarg))
1514 goto err;
1515
1516 err = fuse_copy_one(cs, &outarg, sizeof(outarg));
1517 if (err)
1518 goto err;
1519
1520 err = -ENAMETOOLONG;
1521 if (outarg.namelen > FUSE_NAME_MAX)
1522 goto err;
1523
1524 err = -EINVAL;
1525 if (size != sizeof(outarg) + outarg.namelen + 1)
1526 goto err;
1527
1528 name.name = buf;
1529 name.len = outarg.namelen;
1530 err = fuse_copy_one(cs, buf, outarg.namelen + 1);
1531 if (err)
1532 goto err;
1533 fuse_copy_finish(cs);
1534 buf[outarg.namelen] = 0;
John Muir451d0f52011-12-06 21:50:06 +01001535
1536 down_read(&fc->killsb);
1537 err = -ENOENT;
1538 if (fc->sb)
1539 err = fuse_reverse_inval_entry(fc->sb, outarg.parent,
1540 outarg.child, &name);
John Muir3b463ae2009-05-31 11:13:57 -04001541 up_read(&fc->killsb);
Fang Wenqib2d82ee2009-12-30 18:37:13 +08001542 kfree(buf);
John Muir3b463ae2009-05-31 11:13:57 -04001543 return err;
1544
1545err:
Fang Wenqib2d82ee2009-12-30 18:37:13 +08001546 kfree(buf);
John Muir3b463ae2009-05-31 11:13:57 -04001547 fuse_copy_finish(cs);
1548 return err;
1549}
1550
Miklos Szeredia1d75f22010-07-12 14:41:40 +02001551static int fuse_notify_store(struct fuse_conn *fc, unsigned int size,
1552 struct fuse_copy_state *cs)
1553{
1554 struct fuse_notify_store_out outarg;
1555 struct inode *inode;
1556 struct address_space *mapping;
1557 u64 nodeid;
1558 int err;
1559 pgoff_t index;
1560 unsigned int offset;
1561 unsigned int num;
1562 loff_t file_size;
1563 loff_t end;
1564
1565 err = -EINVAL;
1566 if (size < sizeof(outarg))
1567 goto out_finish;
1568
1569 err = fuse_copy_one(cs, &outarg, sizeof(outarg));
1570 if (err)
1571 goto out_finish;
1572
1573 err = -EINVAL;
1574 if (size - sizeof(outarg) != outarg.size)
1575 goto out_finish;
1576
1577 nodeid = outarg.nodeid;
1578
1579 down_read(&fc->killsb);
1580
1581 err = -ENOENT;
1582 if (!fc->sb)
1583 goto out_up_killsb;
1584
1585 inode = ilookup5(fc->sb, nodeid, fuse_inode_eq, &nodeid);
1586 if (!inode)
1587 goto out_up_killsb;
1588
1589 mapping = inode->i_mapping;
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +03001590 index = outarg.offset >> PAGE_SHIFT;
1591 offset = outarg.offset & ~PAGE_MASK;
Miklos Szeredia1d75f22010-07-12 14:41:40 +02001592 file_size = i_size_read(inode);
1593 end = outarg.offset + outarg.size;
1594 if (end > file_size) {
1595 file_size = end;
1596 fuse_write_update_size(inode, file_size);
1597 }
1598
1599 num = outarg.size;
1600 while (num) {
1601 struct page *page;
1602 unsigned int this_num;
1603
1604 err = -ENOMEM;
1605 page = find_or_create_page(mapping, index,
1606 mapping_gfp_mask(mapping));
1607 if (!page)
1608 goto out_iput;
1609
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +03001610 this_num = min_t(unsigned, num, PAGE_SIZE - offset);
Miklos Szeredia1d75f22010-07-12 14:41:40 +02001611 err = fuse_copy_page(cs, &page, offset, this_num, 0);
Miklos Szeredi063ec1e2014-01-22 19:36:58 +01001612 if (!err && offset == 0 &&
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +03001613 (this_num == PAGE_SIZE || file_size == end))
Miklos Szeredia1d75f22010-07-12 14:41:40 +02001614 SetPageUptodate(page);
1615 unlock_page(page);
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +03001616 put_page(page);
Miklos Szeredia1d75f22010-07-12 14:41:40 +02001617
1618 if (err)
1619 goto out_iput;
1620
1621 num -= this_num;
1622 offset = 0;
1623 index++;
1624 }
1625
1626 err = 0;
1627
1628out_iput:
1629 iput(inode);
1630out_up_killsb:
1631 up_read(&fc->killsb);
1632out_finish:
1633 fuse_copy_finish(cs);
1634 return err;
1635}
1636
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001637static void fuse_retrieve_end(struct fuse_conn *fc, struct fuse_req *req)
1638{
Mel Gormanc6f92f92017-11-15 17:37:55 -08001639 release_pages(req->pages, req->num_pages);
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001640}
1641
1642static int fuse_retrieve(struct fuse_conn *fc, struct inode *inode,
1643 struct fuse_notify_retrieve_out *outarg)
1644{
1645 int err;
1646 struct address_space *mapping = inode->i_mapping;
1647 struct fuse_req *req;
1648 pgoff_t index;
1649 loff_t file_size;
1650 unsigned int num;
1651 unsigned int offset;
Geert Uytterhoeven01574432010-09-30 22:06:21 +02001652 size_t total_len = 0;
Maxim Patlasov4d53dc92012-10-26 19:48:42 +04001653 int num_pages;
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001654
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +03001655 offset = outarg->offset & ~PAGE_MASK;
Maxim Patlasov4d53dc92012-10-26 19:48:42 +04001656 file_size = i_size_read(inode);
1657
1658 num = outarg->size;
1659 if (outarg->offset > file_size)
1660 num = 0;
1661 else if (outarg->offset + num > file_size)
1662 num = file_size - outarg->offset;
1663
1664 num_pages = (num + offset + PAGE_SIZE - 1) >> PAGE_SHIFT;
1665 num_pages = min(num_pages, FUSE_MAX_PAGES_PER_REQ);
1666
1667 req = fuse_get_req(fc, num_pages);
1668 if (IS_ERR(req))
1669 return PTR_ERR(req);
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001670
1671 req->in.h.opcode = FUSE_NOTIFY_REPLY;
1672 req->in.h.nodeid = outarg->nodeid;
1673 req->in.numargs = 2;
1674 req->in.argpages = 1;
Maxim Patlasovb2430d72012-10-26 19:49:24 +04001675 req->page_descs[0].offset = offset;
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001676 req->end = fuse_retrieve_end;
1677
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +03001678 index = outarg->offset >> PAGE_SHIFT;
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001679
Maxim Patlasov4d53dc92012-10-26 19:48:42 +04001680 while (num && req->num_pages < num_pages) {
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001681 struct page *page;
1682 unsigned int this_num;
1683
1684 page = find_get_page(mapping, index);
1685 if (!page)
1686 break;
1687
Kirill A. Shutemov09cbfea2016-04-01 15:29:47 +03001688 this_num = min_t(unsigned, num, PAGE_SIZE - offset);
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001689 req->pages[req->num_pages] = page;
Maxim Patlasov85f40ae2012-10-26 19:49:33 +04001690 req->page_descs[req->num_pages].length = this_num;
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001691 req->num_pages++;
1692
Miklos Szeredic9e67d42012-09-04 18:45:54 +02001693 offset = 0;
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001694 num -= this_num;
1695 total_len += this_num;
Miklos Szeredi48706d02011-12-13 10:36:59 +01001696 index++;
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001697 }
1698 req->misc.retrieve_in.offset = outarg->offset;
1699 req->misc.retrieve_in.size = total_len;
1700 req->in.args[0].size = sizeof(req->misc.retrieve_in);
1701 req->in.args[0].value = &req->misc.retrieve_in;
1702 req->in.args[1].size = total_len;
1703
1704 err = fuse_request_send_notify_reply(fc, req, outarg->notify_unique);
1705 if (err)
1706 fuse_retrieve_end(fc, req);
1707
1708 return err;
1709}
1710
1711static int fuse_notify_retrieve(struct fuse_conn *fc, unsigned int size,
1712 struct fuse_copy_state *cs)
1713{
1714 struct fuse_notify_retrieve_out outarg;
1715 struct inode *inode;
1716 int err;
1717
1718 err = -EINVAL;
1719 if (size != sizeof(outarg))
1720 goto copy_finish;
1721
1722 err = fuse_copy_one(cs, &outarg, sizeof(outarg));
1723 if (err)
1724 goto copy_finish;
1725
1726 fuse_copy_finish(cs);
1727
1728 down_read(&fc->killsb);
1729 err = -ENOENT;
1730 if (fc->sb) {
1731 u64 nodeid = outarg.nodeid;
1732
1733 inode = ilookup5(fc->sb, nodeid, fuse_inode_eq, &nodeid);
1734 if (inode) {
1735 err = fuse_retrieve(fc, inode, &outarg);
1736 iput(inode);
1737 }
1738 }
1739 up_read(&fc->killsb);
1740
1741 return err;
1742
1743copy_finish:
1744 fuse_copy_finish(cs);
1745 return err;
1746}
1747
Tejun Heo85993962008-11-26 12:03:55 +01001748static int fuse_notify(struct fuse_conn *fc, enum fuse_notify_code code,
1749 unsigned int size, struct fuse_copy_state *cs)
1750{
Miklos Szeredi0d278362015-02-26 11:45:47 +01001751 /* Don't try to move pages (yet) */
1752 cs->move_pages = 0;
1753
Tejun Heo85993962008-11-26 12:03:55 +01001754 switch (code) {
Tejun Heo95668a62008-11-26 12:03:55 +01001755 case FUSE_NOTIFY_POLL:
1756 return fuse_notify_poll(fc, size, cs);
1757
John Muir3b463ae2009-05-31 11:13:57 -04001758 case FUSE_NOTIFY_INVAL_INODE:
1759 return fuse_notify_inval_inode(fc, size, cs);
1760
1761 case FUSE_NOTIFY_INVAL_ENTRY:
1762 return fuse_notify_inval_entry(fc, size, cs);
1763
Miklos Szeredia1d75f22010-07-12 14:41:40 +02001764 case FUSE_NOTIFY_STORE:
1765 return fuse_notify_store(fc, size, cs);
1766
Miklos Szeredi2d45ba32010-07-12 14:41:40 +02001767 case FUSE_NOTIFY_RETRIEVE:
1768 return fuse_notify_retrieve(fc, size, cs);
1769
John Muir451d0f52011-12-06 21:50:06 +01001770 case FUSE_NOTIFY_DELETE:
1771 return fuse_notify_delete(fc, size, cs);
1772
Tejun Heo85993962008-11-26 12:03:55 +01001773 default:
Miklos Szeredif6d47a12009-01-26 15:00:59 +01001774 fuse_copy_finish(cs);
Tejun Heo85993962008-11-26 12:03:55 +01001775 return -EINVAL;
1776 }
1777}
1778
Miklos Szeredi334f4852005-09-09 13:10:27 -07001779/* Look up request on processing list by unique ID */
Miklos Szeredi3a2b5b92015-07-01 16:26:04 +02001780static struct fuse_req *request_find(struct fuse_pqueue *fpq, u64 unique)
Miklos Szeredi334f4852005-09-09 13:10:27 -07001781{
Dong Fang05726ac2013-07-30 22:50:01 -04001782 struct fuse_req *req;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001783
Miklos Szeredi3a2b5b92015-07-01 16:26:04 +02001784 list_for_each_entry(req, &fpq->processing, list) {
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001785 if (req->in.h.unique == unique || req->intr_unique == unique)
Miklos Szeredi334f4852005-09-09 13:10:27 -07001786 return req;
1787 }
1788 return NULL;
1789}
1790
1791static int copy_out_args(struct fuse_copy_state *cs, struct fuse_out *out,
1792 unsigned nbytes)
1793{
1794 unsigned reqsize = sizeof(struct fuse_out_header);
1795
1796 if (out->h.error)
1797 return nbytes != reqsize ? -EINVAL : 0;
1798
1799 reqsize += len_args(out->numargs, out->args);
1800
1801 if (reqsize < nbytes || (reqsize > nbytes && !out->argvar))
1802 return -EINVAL;
1803 else if (reqsize > nbytes) {
1804 struct fuse_arg *lastarg = &out->args[out->numargs-1];
1805 unsigned diffsize = reqsize - nbytes;
1806 if (diffsize > lastarg->size)
1807 return -EINVAL;
1808 lastarg->size -= diffsize;
1809 }
1810 return fuse_copy_args(cs, out->numargs, out->argpages, out->args,
1811 out->page_zeroing);
1812}
1813
1814/*
1815 * Write a single reply to a request. First the header is copied from
1816 * the write buffer. The request is then searched on the processing
1817 * list by the unique ID found in the header. If found, then remove
1818 * it from the list and copy the rest of the buffer to the request.
1819 * The request is finished by calling request_end()
1820 */
Miklos Szeredic36960462015-07-01 16:26:09 +02001821static ssize_t fuse_dev_do_write(struct fuse_dev *fud,
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001822 struct fuse_copy_state *cs, size_t nbytes)
Miklos Szeredi334f4852005-09-09 13:10:27 -07001823{
1824 int err;
Miklos Szeredic36960462015-07-01 16:26:09 +02001825 struct fuse_conn *fc = fud->fc;
1826 struct fuse_pqueue *fpq = &fud->pq;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001827 struct fuse_req *req;
1828 struct fuse_out_header oh;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001829
Miklos Szeredi334f4852005-09-09 13:10:27 -07001830 if (nbytes < sizeof(struct fuse_out_header))
1831 return -EINVAL;
1832
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001833 err = fuse_copy_one(cs, &oh, sizeof(oh));
Miklos Szeredi334f4852005-09-09 13:10:27 -07001834 if (err)
1835 goto err_finish;
Tejun Heo85993962008-11-26 12:03:55 +01001836
Miklos Szeredi334f4852005-09-09 13:10:27 -07001837 err = -EINVAL;
Tejun Heo85993962008-11-26 12:03:55 +01001838 if (oh.len != nbytes)
1839 goto err_finish;
1840
1841 /*
1842 * Zero oh.unique indicates unsolicited notification message
1843 * and error contains notification code.
1844 */
1845 if (!oh.unique) {
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001846 err = fuse_notify(fc, oh.error, nbytes - sizeof(oh), cs);
Tejun Heo85993962008-11-26 12:03:55 +01001847 return err ? err : nbytes;
1848 }
1849
1850 err = -EINVAL;
1851 if (oh.error <= -1000 || oh.error > 0)
Miklos Szeredi334f4852005-09-09 13:10:27 -07001852 goto err_finish;
1853
Miklos Szeredi45a91cb2015-07-01 16:26:06 +02001854 spin_lock(&fpq->lock);
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08001855 err = -ENOENT;
Miklos Szeredie96edd92015-07-01 16:26:04 +02001856 if (!fpq->connected)
Miklos Szeredi45a91cb2015-07-01 16:26:06 +02001857 goto err_unlock_pq;
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08001858
Miklos Szeredi3a2b5b92015-07-01 16:26:04 +02001859 req = request_find(fpq, oh.unique);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001860 if (!req)
Miklos Szeredi45a91cb2015-07-01 16:26:06 +02001861 goto err_unlock_pq;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001862
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001863 /* Is it an interrupt reply? */
1864 if (req->intr_unique == oh.unique) {
Miklos Szeredi45a91cb2015-07-01 16:26:06 +02001865 spin_unlock(&fpq->lock);
1866
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001867 err = -EINVAL;
1868 if (nbytes != sizeof(struct fuse_out_header))
Miklos Szeredi46c34a32015-07-01 16:26:07 +02001869 goto err_finish;
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001870
1871 if (oh.error == -ENOSYS)
1872 fc->no_interrupt = 1;
1873 else if (oh.error == -EAGAIN)
Miklos Szeredif88996a2015-07-01 16:26:01 +02001874 queue_interrupt(&fc->iq, req);
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001875
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001876 fuse_copy_finish(cs);
Miklos Szeredia4d27e72006-06-25 05:48:54 -07001877 return nbytes;
1878 }
1879
Miklos Szeredi33e14b42015-07-01 16:26:01 +02001880 clear_bit(FR_SENT, &req->flags);
Miklos Szeredi3a2b5b92015-07-01 16:26:04 +02001881 list_move(&req->list, &fpq->io);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001882 req->out.h = oh;
Miklos Szeredi825d6d32015-07-01 16:25:58 +02001883 set_bit(FR_LOCKED, &req->flags);
Miklos Szeredi45a91cb2015-07-01 16:26:06 +02001884 spin_unlock(&fpq->lock);
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001885 cs->req = req;
Miklos Szeredice534fb2010-05-25 15:06:07 +02001886 if (!req->out.page_replace)
1887 cs->move_pages = 0;
Miklos Szeredi334f4852005-09-09 13:10:27 -07001888
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001889 err = copy_out_args(cs, &req->out, nbytes);
1890 fuse_copy_finish(cs);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001891
Miklos Szeredi45a91cb2015-07-01 16:26:06 +02001892 spin_lock(&fpq->lock);
Miklos Szeredi825d6d32015-07-01 16:25:58 +02001893 clear_bit(FR_LOCKED, &req->flags);
Miklos Szeredie96edd92015-07-01 16:26:04 +02001894 if (!fpq->connected)
Miklos Szeredi0d8e84b2015-07-01 16:25:58 +02001895 err = -ENOENT;
1896 else if (err)
Miklos Szeredi334f4852005-09-09 13:10:27 -07001897 req->out.h.error = -EIO;
Miklos Szeredi77cd9d42015-07-01 16:26:06 +02001898 if (!test_bit(FR_PRIVATE, &req->flags))
1899 list_del_init(&req->list);
Miklos Szeredi45a91cb2015-07-01 16:26:06 +02001900 spin_unlock(&fpq->lock);
Miklos Szeredi46c34a32015-07-01 16:26:07 +02001901
Miklos Szeredi334f4852005-09-09 13:10:27 -07001902 request_end(fc, req);
1903
1904 return err ? err : nbytes;
1905
Miklos Szeredi45a91cb2015-07-01 16:26:06 +02001906 err_unlock_pq:
1907 spin_unlock(&fpq->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001908 err_finish:
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001909 fuse_copy_finish(cs);
Miklos Szeredi334f4852005-09-09 13:10:27 -07001910 return err;
1911}
1912
Al Virofbdbacc2015-04-03 21:53:39 -04001913static ssize_t fuse_dev_write(struct kiocb *iocb, struct iov_iter *from)
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001914{
1915 struct fuse_copy_state cs;
Miklos Szeredicc080e92015-07-01 16:26:08 +02001916 struct fuse_dev *fud = fuse_get_dev(iocb->ki_filp);
1917
1918 if (!fud)
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001919 return -EPERM;
1920
Al Virofbdbacc2015-04-03 21:53:39 -04001921 if (!iter_is_iovec(from))
1922 return -EINVAL;
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001923
Miklos Szeredidc008092015-07-01 16:25:58 +02001924 fuse_copy_init(&cs, 0, from);
Al Virofbdbacc2015-04-03 21:53:39 -04001925
Miklos Szeredic36960462015-07-01 16:26:09 +02001926 return fuse_dev_do_write(fud, &cs, iov_iter_count(from));
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001927}
1928
1929static ssize_t fuse_dev_splice_write(struct pipe_inode_info *pipe,
1930 struct file *out, loff_t *ppos,
1931 size_t len, unsigned int flags)
1932{
1933 unsigned nbuf;
1934 unsigned idx;
1935 struct pipe_buffer *bufs;
1936 struct fuse_copy_state cs;
Miklos Szeredicc080e92015-07-01 16:26:08 +02001937 struct fuse_dev *fud;
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001938 size_t rem;
1939 ssize_t ret;
1940
Miklos Szeredicc080e92015-07-01 16:26:08 +02001941 fud = fuse_get_dev(out);
1942 if (!fud)
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001943 return -EPERM;
1944
Miklos Szeredi07e77dc2010-12-07 20:16:56 +01001945 bufs = kmalloc(pipe->buffers * sizeof(struct pipe_buffer), GFP_KERNEL);
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001946 if (!bufs)
1947 return -ENOMEM;
1948
1949 pipe_lock(pipe);
1950 nbuf = 0;
1951 rem = 0;
1952 for (idx = 0; idx < pipe->nrbufs && rem < len; idx++)
1953 rem += pipe->bufs[(pipe->curbuf + idx) & (pipe->buffers - 1)].len;
1954
1955 ret = -EINVAL;
1956 if (rem < len) {
1957 pipe_unlock(pipe);
1958 goto out;
1959 }
1960
1961 rem = len;
1962 while (rem) {
1963 struct pipe_buffer *ibuf;
1964 struct pipe_buffer *obuf;
1965
1966 BUG_ON(nbuf >= pipe->buffers);
1967 BUG_ON(!pipe->nrbufs);
1968 ibuf = &pipe->bufs[pipe->curbuf];
1969 obuf = &bufs[nbuf];
1970
1971 if (rem >= ibuf->len) {
1972 *obuf = *ibuf;
1973 ibuf->ops = NULL;
1974 pipe->curbuf = (pipe->curbuf + 1) & (pipe->buffers - 1);
1975 pipe->nrbufs--;
1976 } else {
Miklos Szeredi7bf2d1d2016-09-27 10:45:12 +02001977 pipe_buf_get(pipe, ibuf);
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001978 *obuf = *ibuf;
1979 obuf->flags &= ~PIPE_BUF_FLAG_GIFT;
1980 obuf->len = rem;
1981 ibuf->offset += obuf->len;
1982 ibuf->len -= obuf->len;
1983 }
1984 nbuf++;
1985 rem -= obuf->len;
1986 }
1987 pipe_unlock(pipe);
1988
Miklos Szeredidc008092015-07-01 16:25:58 +02001989 fuse_copy_init(&cs, 0, NULL);
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001990 cs.pipebufs = bufs;
Al Viro6c09e942015-04-03 22:06:08 -04001991 cs.nr_segs = nbuf;
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001992 cs.pipe = pipe;
1993
Miklos Szeredice534fb2010-05-25 15:06:07 +02001994 if (flags & SPLICE_F_MOVE)
1995 cs.move_pages = 1;
1996
Miklos Szeredic36960462015-07-01 16:26:09 +02001997 ret = fuse_dev_do_write(fud, &cs, len);
Miklos Szeredidd3bb142010-05-25 15:06:06 +02001998
Miklos Szeredia7796382016-09-27 10:45:12 +02001999 for (idx = 0; idx < nbuf; idx++)
2000 pipe_buf_release(pipe, &bufs[idx]);
2001
Miklos Szeredidd3bb142010-05-25 15:06:06 +02002002out:
2003 kfree(bufs);
2004 return ret;
2005}
2006
Al Viro076ccb72017-07-03 01:02:18 -04002007static __poll_t fuse_dev_poll(struct file *file, poll_table *wait)
Miklos Szeredi334f4852005-09-09 13:10:27 -07002008{
Linus Torvaldsa9a08842018-02-11 14:34:03 -08002009 __poll_t mask = EPOLLOUT | EPOLLWRNORM;
Miklos Szeredif88996a2015-07-01 16:26:01 +02002010 struct fuse_iqueue *fiq;
Miklos Szeredicc080e92015-07-01 16:26:08 +02002011 struct fuse_dev *fud = fuse_get_dev(file);
2012
2013 if (!fud)
Linus Torvaldsa9a08842018-02-11 14:34:03 -08002014 return EPOLLERR;
Miklos Szeredi334f4852005-09-09 13:10:27 -07002015
Miklos Szeredicc080e92015-07-01 16:26:08 +02002016 fiq = &fud->fc->iq;
Miklos Szeredif88996a2015-07-01 16:26:01 +02002017 poll_wait(file, &fiq->waitq, wait);
Miklos Szeredi334f4852005-09-09 13:10:27 -07002018
Miklos Szeredi4ce60812015-07-01 16:26:02 +02002019 spin_lock(&fiq->waitq.lock);
Miklos Szeredie16714d2015-07-01 16:26:01 +02002020 if (!fiq->connected)
Linus Torvaldsa9a08842018-02-11 14:34:03 -08002021 mask = EPOLLERR;
Miklos Szeredif88996a2015-07-01 16:26:01 +02002022 else if (request_pending(fiq))
Linus Torvaldsa9a08842018-02-11 14:34:03 -08002023 mask |= EPOLLIN | EPOLLRDNORM;
Miklos Szeredi4ce60812015-07-01 16:26:02 +02002024 spin_unlock(&fiq->waitq.lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -07002025
2026 return mask;
2027}
2028
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002029/*
2030 * Abort all requests on the given list (pending or processing)
2031 *
Miklos Szeredid7133112006-04-10 22:54:55 -07002032 * This function releases and reacquires fc->lock
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002033 */
Miklos Szeredi334f4852005-09-09 13:10:27 -07002034static void end_requests(struct fuse_conn *fc, struct list_head *head)
2035{
2036 while (!list_empty(head)) {
2037 struct fuse_req *req;
2038 req = list_entry(head->next, struct fuse_req, list);
Miklos Szeredi334f4852005-09-09 13:10:27 -07002039 req->out.h.error = -ECONNABORTED;
Miklos Szeredi33e14b42015-07-01 16:26:01 +02002040 clear_bit(FR_SENT, &req->flags);
Miklos Szeredif377cb72015-07-01 16:26:04 +02002041 list_del_init(&req->list);
Miklos Szeredi334f4852005-09-09 13:10:27 -07002042 request_end(fc, req);
Miklos Szeredi334f4852005-09-09 13:10:27 -07002043 }
2044}
2045
Bryan Green357ccf22011-03-01 16:43:52 -08002046static void end_polls(struct fuse_conn *fc)
2047{
2048 struct rb_node *p;
2049
2050 p = rb_first(&fc->polled_files);
2051
2052 while (p) {
2053 struct fuse_file *ff;
2054 ff = rb_entry(p, struct fuse_file, polled_node);
2055 wake_up_interruptible_all(&ff->poll_wait);
2056
2057 p = rb_next(p);
2058 }
2059}
2060
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002061/*
2062 * Abort all requests.
2063 *
Miklos Szeredib716d422015-07-01 16:25:59 +02002064 * Emergency exit in case of a malicious or accidental deadlock, or just a hung
2065 * filesystem.
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002066 *
Miklos Szeredib716d422015-07-01 16:25:59 +02002067 * The same effect is usually achievable through killing the filesystem daemon
2068 * and all users of the filesystem. The exception is the combination of an
2069 * asynchronous request and the tricky deadlock (see
2070 * Documentation/filesystems/fuse.txt).
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002071 *
Miklos Szeredib716d422015-07-01 16:25:59 +02002072 * Aborting requests under I/O goes as follows: 1: Separate out unlocked
2073 * requests, they should be finished off immediately. Locked requests will be
2074 * finished after unlock; see unlock_request(). 2: Finish off the unlocked
2075 * requests. It is possible that some request will finish before we can. This
2076 * is OK, the request will in that case be removed from the list before we touch
2077 * it.
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002078 */
2079void fuse_abort_conn(struct fuse_conn *fc)
2080{
Miklos Szeredif88996a2015-07-01 16:26:01 +02002081 struct fuse_iqueue *fiq = &fc->iq;
2082
Miklos Szeredid7133112006-04-10 22:54:55 -07002083 spin_lock(&fc->lock);
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002084 if (fc->connected) {
Miklos Szeredic36960462015-07-01 16:26:09 +02002085 struct fuse_dev *fud;
Miklos Szeredib716d422015-07-01 16:25:59 +02002086 struct fuse_req *req, *next;
Miklos Szeredi41f98272015-07-01 16:25:59 +02002087 LIST_HEAD(to_end1);
2088 LIST_HEAD(to_end2);
Miklos Szeredib716d422015-07-01 16:25:59 +02002089
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002090 fc->connected = 0;
Miklos Szeredi51eb01e2006-06-25 05:48:50 -07002091 fc->blocked = 0;
Miklos Szeredi9759bd512015-01-06 10:45:35 +01002092 fuse_set_initialized(fc);
Miklos Szeredic36960462015-07-01 16:26:09 +02002093 list_for_each_entry(fud, &fc->devices, entry) {
2094 struct fuse_pqueue *fpq = &fud->pq;
2095
2096 spin_lock(&fpq->lock);
2097 fpq->connected = 0;
2098 list_for_each_entry_safe(req, next, &fpq->io, list) {
2099 req->out.h.error = -ECONNABORTED;
2100 spin_lock(&req->waitq.lock);
2101 set_bit(FR_ABORTED, &req->flags);
2102 if (!test_bit(FR_LOCKED, &req->flags)) {
2103 set_bit(FR_PRIVATE, &req->flags);
2104 list_move(&req->list, &to_end1);
2105 }
2106 spin_unlock(&req->waitq.lock);
Miklos Szeredi77cd9d42015-07-01 16:26:06 +02002107 }
Miklos Szeredic36960462015-07-01 16:26:09 +02002108 list_splice_init(&fpq->processing, &to_end2);
2109 spin_unlock(&fpq->lock);
Miklos Szeredib716d422015-07-01 16:25:59 +02002110 }
Miklos Szeredi41f98272015-07-01 16:25:59 +02002111 fc->max_background = UINT_MAX;
2112 flush_bg_queue(fc);
Miklos Szeredi8c911892015-07-01 16:26:02 +02002113
Miklos Szeredi4ce60812015-07-01 16:26:02 +02002114 spin_lock(&fiq->waitq.lock);
Miklos Szeredi8c911892015-07-01 16:26:02 +02002115 fiq->connected = 0;
Miklos Szeredif88996a2015-07-01 16:26:01 +02002116 list_splice_init(&fiq->pending, &to_end2);
Tahsin Erdogana8a86d72017-01-12 12:04:04 -08002117 list_for_each_entry(req, &to_end2, list)
2118 clear_bit(FR_PENDING, &req->flags);
Miklos Szeredi8c911892015-07-01 16:26:02 +02002119 while (forget_pending(fiq))
2120 kfree(dequeue_forget(fiq, 1, NULL));
Miklos Szeredi4ce60812015-07-01 16:26:02 +02002121 wake_up_all_locked(&fiq->waitq);
2122 spin_unlock(&fiq->waitq.lock);
Miklos Szeredi8c911892015-07-01 16:26:02 +02002123 kill_fasync(&fiq->fasync, SIGIO, POLL_IN);
Miklos Szerediee314a82015-07-01 16:26:08 +02002124 end_polls(fc);
2125 wake_up_all(&fc->blocked_waitq);
2126 spin_unlock(&fc->lock);
Miklos Szeredi8c911892015-07-01 16:26:02 +02002127
Miklos Szeredi41f98272015-07-01 16:25:59 +02002128 while (!list_empty(&to_end1)) {
2129 req = list_first_entry(&to_end1, struct fuse_req, list);
Miklos Szeredib716d422015-07-01 16:25:59 +02002130 __fuse_get_request(req);
Miklos Szeredif377cb72015-07-01 16:26:04 +02002131 list_del_init(&req->list);
Miklos Szeredib716d422015-07-01 16:25:59 +02002132 request_end(fc, req);
Miklos Szeredib716d422015-07-01 16:25:59 +02002133 }
Miklos Szeredi41f98272015-07-01 16:25:59 +02002134 end_requests(fc, &to_end2);
Miklos Szerediee314a82015-07-01 16:26:08 +02002135 } else {
2136 spin_unlock(&fc->lock);
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002137 }
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002138}
Tejun Heo08cbf542009-04-14 10:54:53 +09002139EXPORT_SYMBOL_GPL(fuse_abort_conn);
Miklos Szeredi69a53bf2006-01-16 22:14:41 -08002140
Tejun Heo08cbf542009-04-14 10:54:53 +09002141int fuse_dev_release(struct inode *inode, struct file *file)
Miklos Szeredi334f4852005-09-09 13:10:27 -07002142{
Miklos Szeredicc080e92015-07-01 16:26:08 +02002143 struct fuse_dev *fud = fuse_get_dev(file);
2144
2145 if (fud) {
2146 struct fuse_conn *fc = fud->fc;
Miklos Szeredic36960462015-07-01 16:26:09 +02002147 struct fuse_pqueue *fpq = &fud->pq;
Miklos Szeredicc080e92015-07-01 16:26:08 +02002148
Miklos Szeredic36960462015-07-01 16:26:09 +02002149 WARN_ON(!list_empty(&fpq->io));
2150 end_requests(fc, &fpq->processing);
2151 /* Are we the last open device? */
2152 if (atomic_dec_and_test(&fc->dev_count)) {
2153 WARN_ON(fc->iq.fasync != NULL);
2154 fuse_abort_conn(fc);
2155 }
Miklos Szeredicc080e92015-07-01 16:26:08 +02002156 fuse_dev_free(fud);
Jeff Dike385a17b2006-04-10 22:54:52 -07002157 }
Miklos Szeredi334f4852005-09-09 13:10:27 -07002158 return 0;
2159}
Tejun Heo08cbf542009-04-14 10:54:53 +09002160EXPORT_SYMBOL_GPL(fuse_dev_release);
Miklos Szeredi334f4852005-09-09 13:10:27 -07002161
Jeff Dike385a17b2006-04-10 22:54:52 -07002162static int fuse_dev_fasync(int fd, struct file *file, int on)
2163{
Miklos Szeredicc080e92015-07-01 16:26:08 +02002164 struct fuse_dev *fud = fuse_get_dev(file);
2165
2166 if (!fud)
Miklos Szeredia87046d2006-04-10 22:54:56 -07002167 return -EPERM;
Jeff Dike385a17b2006-04-10 22:54:52 -07002168
2169 /* No locking - fasync_helper does its own locking */
Miklos Szeredicc080e92015-07-01 16:26:08 +02002170 return fasync_helper(fd, file, on, &fud->fc->iq.fasync);
Jeff Dike385a17b2006-04-10 22:54:52 -07002171}
2172
Miklos Szeredi00c570f2015-07-01 16:26:08 +02002173static int fuse_device_clone(struct fuse_conn *fc, struct file *new)
2174{
Miklos Szeredicc080e92015-07-01 16:26:08 +02002175 struct fuse_dev *fud;
2176
Miklos Szeredi00c570f2015-07-01 16:26:08 +02002177 if (new->private_data)
2178 return -EINVAL;
2179
Miklos Szeredicc080e92015-07-01 16:26:08 +02002180 fud = fuse_dev_alloc(fc);
2181 if (!fud)
2182 return -ENOMEM;
2183
2184 new->private_data = fud;
Miklos Szeredic36960462015-07-01 16:26:09 +02002185 atomic_inc(&fc->dev_count);
Miklos Szeredi00c570f2015-07-01 16:26:08 +02002186
2187 return 0;
2188}
2189
2190static long fuse_dev_ioctl(struct file *file, unsigned int cmd,
2191 unsigned long arg)
2192{
2193 int err = -ENOTTY;
2194
2195 if (cmd == FUSE_DEV_IOC_CLONE) {
2196 int oldfd;
2197
2198 err = -EFAULT;
2199 if (!get_user(oldfd, (__u32 __user *) arg)) {
2200 struct file *old = fget(oldfd);
2201
2202 err = -EINVAL;
2203 if (old) {
Jann Horn8ed1f0e2015-08-16 20:27:01 +02002204 struct fuse_dev *fud = NULL;
2205
2206 /*
2207 * Check against file->f_op because CUSE
2208 * uses the same ioctl handler.
2209 */
2210 if (old->f_op == file->f_op &&
2211 old->f_cred->user_ns == file->f_cred->user_ns)
2212 fud = fuse_get_dev(old);
Miklos Szeredi00c570f2015-07-01 16:26:08 +02002213
Miklos Szeredicc080e92015-07-01 16:26:08 +02002214 if (fud) {
Miklos Szeredi00c570f2015-07-01 16:26:08 +02002215 mutex_lock(&fuse_mutex);
Miklos Szeredicc080e92015-07-01 16:26:08 +02002216 err = fuse_device_clone(fud->fc, file);
Miklos Szeredi00c570f2015-07-01 16:26:08 +02002217 mutex_unlock(&fuse_mutex);
2218 }
2219 fput(old);
2220 }
2221 }
2222 }
2223 return err;
2224}
2225
Arjan van de Ven4b6f5d22006-03-28 01:56:42 -08002226const struct file_operations fuse_dev_operations = {
Miklos Szeredi334f4852005-09-09 13:10:27 -07002227 .owner = THIS_MODULE,
Tom Van Braeckel94e4fe22015-01-12 05:22:16 +01002228 .open = fuse_dev_open,
Miklos Szeredi334f4852005-09-09 13:10:27 -07002229 .llseek = no_llseek,
Al Virofbdbacc2015-04-03 21:53:39 -04002230 .read_iter = fuse_dev_read,
Miklos Szeredic3021622010-05-25 15:06:07 +02002231 .splice_read = fuse_dev_splice_read,
Al Virofbdbacc2015-04-03 21:53:39 -04002232 .write_iter = fuse_dev_write,
Miklos Szeredidd3bb142010-05-25 15:06:06 +02002233 .splice_write = fuse_dev_splice_write,
Miklos Szeredi334f4852005-09-09 13:10:27 -07002234 .poll = fuse_dev_poll,
2235 .release = fuse_dev_release,
Jeff Dike385a17b2006-04-10 22:54:52 -07002236 .fasync = fuse_dev_fasync,
Miklos Szeredi00c570f2015-07-01 16:26:08 +02002237 .unlocked_ioctl = fuse_dev_ioctl,
2238 .compat_ioctl = fuse_dev_ioctl,
Miklos Szeredi334f4852005-09-09 13:10:27 -07002239};
Tejun Heo08cbf542009-04-14 10:54:53 +09002240EXPORT_SYMBOL_GPL(fuse_dev_operations);
Miklos Szeredi334f4852005-09-09 13:10:27 -07002241
2242static struct miscdevice fuse_miscdevice = {
2243 .minor = FUSE_MINOR,
2244 .name = "fuse",
2245 .fops = &fuse_dev_operations,
2246};
2247
2248int __init fuse_dev_init(void)
2249{
2250 int err = -ENOMEM;
2251 fuse_req_cachep = kmem_cache_create("fuse_request",
2252 sizeof(struct fuse_req),
Paul Mundt20c2df82007-07-20 10:11:58 +09002253 0, 0, NULL);
Miklos Szeredi334f4852005-09-09 13:10:27 -07002254 if (!fuse_req_cachep)
2255 goto out;
2256
2257 err = misc_register(&fuse_miscdevice);
2258 if (err)
2259 goto out_cache_clean;
2260
2261 return 0;
2262
2263 out_cache_clean:
2264 kmem_cache_destroy(fuse_req_cachep);
2265 out:
2266 return err;
2267}
2268
2269void fuse_dev_cleanup(void)
2270{
2271 misc_deregister(&fuse_miscdevice);
2272 kmem_cache_destroy(fuse_req_cachep);
2273}