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Miklos Szeredid8a5ba42005-09-09 13:10:26 -07001/*
2 FUSE: Filesystem in Userspace
Miklos Szeredi1729a162008-11-26 12:03:54 +01003 Copyright (C) 2001-2008 Miklos Szeredi <miklos@szeredi.hu>
Miklos Szeredid8a5ba42005-09-09 13:10:26 -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/pagemap.h>
12#include <linux/slab.h>
13#include <linux/file.h>
Miklos Szeredid8a5ba42005-09-09 13:10:26 -070014#include <linux/seq_file.h>
15#include <linux/init.h>
16#include <linux/module.h>
Csaba Henk487ea5a2009-08-26 19:17:22 +020017#include <linux/moduleparam.h>
Miklos Szeredid8a5ba42005-09-09 13:10:26 -070018#include <linux/parser.h>
19#include <linux/statfs.h>
Miklos Szeredi9c8ef562006-06-25 05:48:55 -070020#include <linux/random.h>
Alexey Dobriyane8edc6e2007-05-21 01:22:52 +040021#include <linux/sched.h>
Miklos Szeredidbd561d2008-07-25 01:49:00 -070022#include <linux/exportfs.h>
Miklos Szeredid8a5ba42005-09-09 13:10:26 -070023
24MODULE_AUTHOR("Miklos Szeredi <miklos@szeredi.hu>");
25MODULE_DESCRIPTION("Filesystem in Userspace");
26MODULE_LICENSE("GPL");
27
Christoph Lametere18b8902006-12-06 20:33:20 -080028static struct kmem_cache *fuse_inode_cachep;
Miklos Szeredibafa9652006-06-25 05:48:51 -070029struct list_head fuse_conn_list;
30DEFINE_MUTEX(fuse_mutex);
Miklos Szeredid8a5ba42005-09-09 13:10:26 -070031
Csaba Henk487ea5a2009-08-26 19:17:22 +020032static int set_global_limit(const char *val, struct kernel_param *kp);
33
Csaba Henk79a9d992009-08-26 19:18:24 +020034unsigned max_user_bgreq;
Csaba Henk487ea5a2009-08-26 19:17:22 +020035module_param_call(max_user_bgreq, set_global_limit, param_get_uint,
36 &max_user_bgreq, 0644);
37__MODULE_PARM_TYPE(max_user_bgreq, "uint");
38MODULE_PARM_DESC(max_user_bgreq,
39 "Global limit for the maximum number of backgrounded requests an "
40 "unprivileged user can set");
41
Csaba Henk79a9d992009-08-26 19:18:24 +020042unsigned max_user_congthresh;
Csaba Henk487ea5a2009-08-26 19:17:22 +020043module_param_call(max_user_congthresh, set_global_limit, param_get_uint,
44 &max_user_congthresh, 0644);
45__MODULE_PARM_TYPE(max_user_congthresh, "uint");
46MODULE_PARM_DESC(max_user_congthresh,
47 "Global limit for the maximum congestion threshold an "
48 "unprivileged user can set");
49
Miklos Szeredid8a5ba42005-09-09 13:10:26 -070050#define FUSE_SUPER_MAGIC 0x65735546
51
Miklos Szeredid1875db2008-02-08 04:21:43 -080052#define FUSE_DEFAULT_BLKSIZE 512
53
Csaba Henk7a6d3c82009-07-01 17:28:41 -070054/** Maximum number of outstanding background requests */
55#define FUSE_DEFAULT_MAX_BACKGROUND 12
56
57/** Congestion starts at 75% of maximum */
58#define FUSE_DEFAULT_CONGESTION_THRESHOLD (FUSE_DEFAULT_MAX_BACKGROUND * 3 / 4)
59
Miklos Szeredid8a5ba42005-09-09 13:10:26 -070060struct fuse_mount_data {
61 int fd;
62 unsigned rootmode;
63 unsigned user_id;
Miklos Szeredi87729a52005-09-09 13:10:34 -070064 unsigned group_id;
Miklos Szeredi1729a162008-11-26 12:03:54 +010065 unsigned fd_present:1;
66 unsigned rootmode_present:1;
67 unsigned user_id_present:1;
68 unsigned group_id_present:1;
Miklos Szeredi1e9a4ed2005-09-09 13:10:31 -070069 unsigned flags;
Miklos Szeredidb50b962005-09-09 13:10:33 -070070 unsigned max_read;
Miklos Szeredid8091612006-12-06 20:35:48 -080071 unsigned blksize;
Miklos Szeredid8a5ba42005-09-09 13:10:26 -070072};
73
Randy Dunlapa2daff62011-05-31 14:09:00 -070074struct fuse_forget_link *fuse_alloc_forget(void)
Miklos Szeredi07e77dc2010-12-07 20:16:56 +010075{
76 return kzalloc(sizeof(struct fuse_forget_link), GFP_KERNEL);
77}
78
Miklos Szeredid8a5ba42005-09-09 13:10:26 -070079static struct inode *fuse_alloc_inode(struct super_block *sb)
80{
81 struct inode *inode;
82 struct fuse_inode *fi;
83
Christoph Lametere94b1762006-12-06 20:33:17 -080084 inode = kmem_cache_alloc(fuse_inode_cachep, GFP_KERNEL);
Miklos Szeredid8a5ba42005-09-09 13:10:26 -070085 if (!inode)
86 return NULL;
87
88 fi = get_fuse_inode(inode);
Miklos Szeredi0a0898c2006-07-30 03:04:10 -070089 fi->i_time = 0;
Miklos Szeredid8a5ba42005-09-09 13:10:26 -070090 fi->nodeid = 0;
Miklos Szeredi9e6268d2005-09-09 13:10:29 -070091 fi->nlookup = 0;
John Muirfbee36b2007-11-28 16:22:02 -080092 fi->attr_version = 0;
Miklos Szeredi3be5a522008-04-30 00:54:41 -070093 fi->writectr = 0;
Miklos Szeredi93a8c3c2007-10-18 03:07:03 -070094 INIT_LIST_HEAD(&fi->write_files);
Miklos Szeredi3be5a522008-04-30 00:54:41 -070095 INIT_LIST_HEAD(&fi->queued_writes);
96 INIT_LIST_HEAD(&fi->writepages);
97 init_waitqueue_head(&fi->page_waitq);
Miklos Szeredi07e77dc2010-12-07 20:16:56 +010098 fi->forget = fuse_alloc_forget();
99 if (!fi->forget) {
Miklos Szeredie5e55582005-09-09 13:10:28 -0700100 kmem_cache_free(fuse_inode_cachep, inode);
101 return NULL;
102 }
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700103
104 return inode;
105}
106
Nick Pigginfa0d7e32011-01-07 17:49:49 +1100107static void fuse_i_callback(struct rcu_head *head)
108{
109 struct inode *inode = container_of(head, struct inode, i_rcu);
Nick Pigginfa0d7e32011-01-07 17:49:49 +1100110 kmem_cache_free(fuse_inode_cachep, inode);
111}
112
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700113static void fuse_destroy_inode(struct inode *inode)
114{
Miklos Szeredie5e55582005-09-09 13:10:28 -0700115 struct fuse_inode *fi = get_fuse_inode(inode);
Miklos Szeredi93a8c3c2007-10-18 03:07:03 -0700116 BUG_ON(!list_empty(&fi->write_files));
Miklos Szeredi3be5a522008-04-30 00:54:41 -0700117 BUG_ON(!list_empty(&fi->queued_writes));
Miklos Szeredi07e77dc2010-12-07 20:16:56 +0100118 kfree(fi->forget);
Nick Pigginfa0d7e32011-01-07 17:49:49 +1100119 call_rcu(&inode->i_rcu, fuse_i_callback);
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700120}
121
Al Virob57922d2010-06-07 14:34:48 -0400122static void fuse_evict_inode(struct inode *inode)
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700123{
Al Virob57922d2010-06-07 14:34:48 -0400124 truncate_inode_pages(&inode->i_data, 0);
125 end_writeback(inode);
Miklos Szeredi1e9a4ed2005-09-09 13:10:31 -0700126 if (inode->i_sb->s_flags & MS_ACTIVE) {
127 struct fuse_conn *fc = get_fuse_conn(inode);
Miklos Szeredie5e55582005-09-09 13:10:28 -0700128 struct fuse_inode *fi = get_fuse_inode(inode);
Miklos Szeredi07e77dc2010-12-07 20:16:56 +0100129 fuse_queue_forget(fc, fi->forget, fi->nodeid, fi->nlookup);
130 fi->forget = NULL;
Miklos Szeredie5e55582005-09-09 13:10:28 -0700131 }
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700132}
133
Miklos Szeredi71421252006-06-25 05:48:52 -0700134static int fuse_remount_fs(struct super_block *sb, int *flags, char *data)
135{
136 if (*flags & MS_MANDLOCK)
137 return -EINVAL;
138
139 return 0;
140}
141
Miklos Szeredi3be5a522008-04-30 00:54:41 -0700142void fuse_change_attributes_common(struct inode *inode, struct fuse_attr *attr,
143 u64 attr_valid)
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700144{
Miklos Szeredi9ffbb912006-10-17 00:10:06 -0700145 struct fuse_conn *fc = get_fuse_conn(inode);
Miklos Szerediebc14c42007-10-16 23:31:03 -0700146 struct fuse_inode *fi = get_fuse_inode(inode);
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700147
Miklos Szeredi1fb69e72007-10-18 03:06:58 -0700148 fi->attr_version = ++fc->attr_version;
149 fi->i_time = attr_valid;
150
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700151 inode->i_ino = attr->ino;
Miklos Szerediebc14c42007-10-16 23:31:03 -0700152 inode->i_mode = (inode->i_mode & S_IFMT) | (attr->mode & 07777);
Miklos Szeredibfe86842011-10-28 14:13:29 +0200153 set_nlink(inode, attr->nlink);
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700154 inode->i_uid = attr->uid;
155 inode->i_gid = attr->gid;
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700156 inode->i_blocks = attr->blocks;
157 inode->i_atime.tv_sec = attr->atime;
158 inode->i_atime.tv_nsec = attr->atimensec;
159 inode->i_mtime.tv_sec = attr->mtime;
160 inode->i_mtime.tv_nsec = attr->mtimensec;
161 inode->i_ctime.tv_sec = attr->ctime;
162 inode->i_ctime.tv_nsec = attr->ctimensec;
Miklos Szeredie00d2c22007-10-16 23:31:01 -0700163
Miklos Szeredi0e9663e2007-10-18 03:07:05 -0700164 if (attr->blksize != 0)
165 inode->i_blkbits = ilog2(attr->blksize);
166 else
167 inode->i_blkbits = inode->i_sb->s_blocksize_bits;
168
Miklos Szerediebc14c42007-10-16 23:31:03 -0700169 /*
170 * Don't set the sticky bit in i_mode, unless we want the VFS
171 * to check permissions. This prevents failures due to the
172 * check in may_delete().
173 */
174 fi->orig_i_mode = inode->i_mode;
175 if (!(fc->flags & FUSE_DEFAULT_PERMISSIONS))
176 inode->i_mode &= ~S_ISVTX;
Miklos Szeredi3be5a522008-04-30 00:54:41 -0700177}
178
179void fuse_change_attributes(struct inode *inode, struct fuse_attr *attr,
180 u64 attr_valid, u64 attr_version)
181{
182 struct fuse_conn *fc = get_fuse_conn(inode);
183 struct fuse_inode *fi = get_fuse_inode(inode);
184 loff_t oldsize;
185
186 spin_lock(&fc->lock);
187 if (attr_version != 0 && fi->attr_version > attr_version) {
188 spin_unlock(&fc->lock);
189 return;
190 }
191
192 fuse_change_attributes_common(inode, attr, attr_valid);
Miklos Szerediebc14c42007-10-16 23:31:03 -0700193
Miklos Szeredie00d2c22007-10-16 23:31:01 -0700194 oldsize = inode->i_size;
195 i_size_write(inode, attr->size);
196 spin_unlock(&fc->lock);
197
198 if (S_ISREG(inode->i_mode) && oldsize != attr->size) {
npiggin@suse.dec08d3b02009-08-21 02:35:06 +1000199 truncate_pagecache(inode, oldsize, attr->size);
Miklos Szeredib1009972007-10-16 23:31:01 -0700200 invalidate_inode_pages2(inode->i_mapping);
Miklos Szeredie00d2c22007-10-16 23:31:01 -0700201 }
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700202}
203
204static void fuse_init_inode(struct inode *inode, struct fuse_attr *attr)
205{
206 inode->i_mode = attr->mode & S_IFMT;
Miklos Szeredi9ffbb912006-10-17 00:10:06 -0700207 inode->i_size = attr->size;
Miklos Szeredie5e55582005-09-09 13:10:28 -0700208 if (S_ISREG(inode->i_mode)) {
209 fuse_init_common(inode);
Miklos Szeredib6aeade2005-09-09 13:10:30 -0700210 fuse_init_file_inode(inode);
Miklos Szeredie5e55582005-09-09 13:10:28 -0700211 } else if (S_ISDIR(inode->i_mode))
212 fuse_init_dir(inode);
213 else if (S_ISLNK(inode->i_mode))
214 fuse_init_symlink(inode);
215 else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) ||
216 S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) {
217 fuse_init_common(inode);
218 init_special_inode(inode, inode->i_mode,
219 new_decode_dev(attr->rdev));
Miklos Szeredi39ee0592006-01-06 00:19:43 -0800220 } else
221 BUG();
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700222}
223
John Muir3b463ae2009-05-31 11:13:57 -0400224int fuse_inode_eq(struct inode *inode, void *_nodeidp)
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700225{
Miklos Szeredib48badf2008-04-30 00:54:44 -0700226 u64 nodeid = *(u64 *) _nodeidp;
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700227 if (get_node_id(inode) == nodeid)
228 return 1;
229 else
230 return 0;
231}
232
233static int fuse_inode_set(struct inode *inode, void *_nodeidp)
234{
Miklos Szeredib48badf2008-04-30 00:54:44 -0700235 u64 nodeid = *(u64 *) _nodeidp;
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700236 get_fuse_inode(inode)->nodeid = nodeid;
237 return 0;
238}
239
Miklos Szeredib48badf2008-04-30 00:54:44 -0700240struct inode *fuse_iget(struct super_block *sb, u64 nodeid,
Miklos Szeredi1fb69e72007-10-18 03:06:58 -0700241 int generation, struct fuse_attr *attr,
242 u64 attr_valid, u64 attr_version)
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700243{
244 struct inode *inode;
Miklos Szeredi9e6268d2005-09-09 13:10:29 -0700245 struct fuse_inode *fi;
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700246 struct fuse_conn *fc = get_fuse_conn_super(sb);
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700247
248 retry:
249 inode = iget5_locked(sb, nodeid, fuse_inode_eq, fuse_inode_set, &nodeid);
250 if (!inode)
251 return NULL;
252
253 if ((inode->i_state & I_NEW)) {
Miklos Szeredib36c31b2005-09-09 13:10:38 -0700254 inode->i_flags |= S_NOATIME|S_NOCMTIME;
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700255 inode->i_generation = generation;
256 inode->i_data.backing_dev_info = &fc->bdi;
257 fuse_init_inode(inode, attr);
258 unlock_new_inode(inode);
259 } else if ((inode->i_mode ^ attr->mode) & S_IFMT) {
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700260 /* Inode has changed type, any I/O on the old should fail */
261 make_bad_inode(inode);
262 iput(inode);
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700263 goto retry;
264 }
265
Miklos Szeredi9e6268d2005-09-09 13:10:29 -0700266 fi = get_fuse_inode(inode);
Miklos Szeredi8da5ff22006-10-17 00:10:08 -0700267 spin_lock(&fc->lock);
Miklos Szeredi1729a162008-11-26 12:03:54 +0100268 fi->nlookup++;
Miklos Szeredi8da5ff22006-10-17 00:10:08 -0700269 spin_unlock(&fc->lock);
Miklos Szeredi1fb69e72007-10-18 03:06:58 -0700270 fuse_change_attributes(inode, attr, attr_valid, attr_version);
271
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700272 return inode;
273}
274
John Muir3b463ae2009-05-31 11:13:57 -0400275int fuse_reverse_inval_inode(struct super_block *sb, u64 nodeid,
276 loff_t offset, loff_t len)
277{
278 struct inode *inode;
279 pgoff_t pg_start;
280 pgoff_t pg_end;
281
282 inode = ilookup5(sb, nodeid, fuse_inode_eq, &nodeid);
283 if (!inode)
284 return -ENOENT;
285
286 fuse_invalidate_attr(inode);
287 if (offset >= 0) {
288 pg_start = offset >> PAGE_CACHE_SHIFT;
289 if (len <= 0)
290 pg_end = -1;
291 else
292 pg_end = (offset + len - 1) >> PAGE_CACHE_SHIFT;
293 invalidate_inode_pages2_range(inode->i_mapping,
294 pg_start, pg_end);
295 }
296 iput(inode);
297 return 0;
298}
299
Al Viro42faad92008-04-24 07:21:56 -0400300static void fuse_umount_begin(struct super_block *sb)
Miklos Szeredi69a53bf2006-01-16 22:14:41 -0800301{
Al Viro42faad92008-04-24 07:21:56 -0400302 fuse_abort_conn(get_fuse_conn_super(sb));
Miklos Szeredi69a53bf2006-01-16 22:14:41 -0800303}
304
Miklos Szeredi0ec7ca42006-12-06 20:35:52 -0800305static void fuse_send_destroy(struct fuse_conn *fc)
306{
307 struct fuse_req *req = fc->destroy_req;
308 if (req && fc->conn_init) {
309 fc->destroy_req = NULL;
310 req->in.h.opcode = FUSE_DESTROY;
311 req->force = 1;
Tejun Heob93f8582008-11-26 12:03:55 +0100312 fuse_request_send(fc, req);
Miklos Szeredi0ec7ca42006-12-06 20:35:52 -0800313 fuse_put_request(fc, req);
314 }
315}
316
Tejun Heoa325f9b2009-04-14 10:54:52 +0900317static void fuse_bdi_destroy(struct fuse_conn *fc)
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700318{
Tejun Heoa325f9b2009-04-14 10:54:52 +0900319 if (fc->bdi_initialized)
320 bdi_destroy(&fc->bdi);
321}
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700322
Tejun Heo08cbf542009-04-14 10:54:53 +0900323void fuse_conn_kill(struct fuse_conn *fc)
Tejun Heoa325f9b2009-04-14 10:54:52 +0900324{
Miklos Szeredid7133112006-04-10 22:54:55 -0700325 spin_lock(&fc->lock);
Miklos Szeredi9ba7cbb2006-01-16 22:14:34 -0800326 fc->connected = 0;
Miklos Szeredi51eb01e2006-06-25 05:48:50 -0700327 fc->blocked = 0;
Miklos Szeredid7133112006-04-10 22:54:55 -0700328 spin_unlock(&fc->lock);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700329 /* Flush all readers on this fs */
Jeff Dike385a17b2006-04-10 22:54:52 -0700330 kill_fasync(&fc->fasync, SIGIO, POLL_IN);
Miklos Szeredi334f4852005-09-09 13:10:27 -0700331 wake_up_all(&fc->waitq);
Miklos Szeredi51eb01e2006-06-25 05:48:50 -0700332 wake_up_all(&fc->blocked_waitq);
Miklos Szeredide5e3de2007-10-16 23:31:00 -0700333 wake_up_all(&fc->reserved_req_waitq);
Miklos Szeredibafa9652006-06-25 05:48:51 -0700334 mutex_lock(&fuse_mutex);
335 list_del(&fc->entry);
336 fuse_ctl_remove_conn(fc);
337 mutex_unlock(&fuse_mutex);
Tejun Heoa325f9b2009-04-14 10:54:52 +0900338 fuse_bdi_destroy(fc);
339}
Tejun Heo08cbf542009-04-14 10:54:53 +0900340EXPORT_SYMBOL_GPL(fuse_conn_kill);
Tejun Heoa325f9b2009-04-14 10:54:52 +0900341
342static void fuse_put_super(struct super_block *sb)
343{
344 struct fuse_conn *fc = get_fuse_conn_super(sb);
345
346 fuse_send_destroy(fc);
347 fuse_conn_kill(fc);
Miklos Szeredibafa9652006-06-25 05:48:51 -0700348 fuse_conn_put(fc);
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700349}
350
Miklos Szeredie5e55582005-09-09 13:10:28 -0700351static void convert_fuse_statfs(struct kstatfs *stbuf, struct fuse_kstatfs *attr)
352{
353 stbuf->f_type = FUSE_SUPER_MAGIC;
354 stbuf->f_bsize = attr->bsize;
Miklos Szeredide5f1202006-01-06 00:19:37 -0800355 stbuf->f_frsize = attr->frsize;
Miklos Szeredie5e55582005-09-09 13:10:28 -0700356 stbuf->f_blocks = attr->blocks;
357 stbuf->f_bfree = attr->bfree;
358 stbuf->f_bavail = attr->bavail;
359 stbuf->f_files = attr->files;
360 stbuf->f_ffree = attr->ffree;
361 stbuf->f_namelen = attr->namelen;
362 /* fsid is left zero */
363}
364
David Howells726c3342006-06-23 02:02:58 -0700365static int fuse_statfs(struct dentry *dentry, struct kstatfs *buf)
Miklos Szeredie5e55582005-09-09 13:10:28 -0700366{
David Howells726c3342006-06-23 02:02:58 -0700367 struct super_block *sb = dentry->d_sb;
Miklos Szeredie5e55582005-09-09 13:10:28 -0700368 struct fuse_conn *fc = get_fuse_conn_super(sb);
369 struct fuse_req *req;
370 struct fuse_statfs_out outarg;
371 int err;
372
Miklos Szeredie57ac682007-10-18 03:06:58 -0700373 if (!fuse_allow_task(fc, current)) {
374 buf->f_type = FUSE_SUPER_MAGIC;
375 return 0;
376 }
377
Miklos Szeredice1d5a42006-04-10 22:54:58 -0700378 req = fuse_get_req(fc);
379 if (IS_ERR(req))
380 return PTR_ERR(req);
Miklos Szeredie5e55582005-09-09 13:10:28 -0700381
Miklos Szeredide5f1202006-01-06 00:19:37 -0800382 memset(&outarg, 0, sizeof(outarg));
Miklos Szeredie5e55582005-09-09 13:10:28 -0700383 req->in.numargs = 0;
384 req->in.h.opcode = FUSE_STATFS;
Miklos Szeredi5b35e8e2006-09-29 01:59:34 -0700385 req->in.h.nodeid = get_node_id(dentry->d_inode);
Miklos Szeredie5e55582005-09-09 13:10:28 -0700386 req->out.numargs = 1;
Miklos Szeredide5f1202006-01-06 00:19:37 -0800387 req->out.args[0].size =
388 fc->minor < 4 ? FUSE_COMPAT_STATFS_SIZE : sizeof(outarg);
Miklos Szeredie5e55582005-09-09 13:10:28 -0700389 req->out.args[0].value = &outarg;
Tejun Heob93f8582008-11-26 12:03:55 +0100390 fuse_request_send(fc, req);
Miklos Szeredie5e55582005-09-09 13:10:28 -0700391 err = req->out.h.error;
392 if (!err)
393 convert_fuse_statfs(buf, &outarg.st);
394 fuse_put_request(fc, req);
395 return err;
396}
397
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700398enum {
399 OPT_FD,
400 OPT_ROOTMODE,
401 OPT_USER_ID,
Miklos Szeredi87729a52005-09-09 13:10:34 -0700402 OPT_GROUP_ID,
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700403 OPT_DEFAULT_PERMISSIONS,
404 OPT_ALLOW_OTHER,
Miklos Szeredidb50b962005-09-09 13:10:33 -0700405 OPT_MAX_READ,
Miklos Szeredid8091612006-12-06 20:35:48 -0800406 OPT_BLKSIZE,
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700407 OPT_ERR
408};
409
Steven Whitehousea447c092008-10-13 10:46:57 +0100410static const match_table_t tokens = {
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700411 {OPT_FD, "fd=%u"},
412 {OPT_ROOTMODE, "rootmode=%o"},
413 {OPT_USER_ID, "user_id=%u"},
Miklos Szeredi87729a52005-09-09 13:10:34 -0700414 {OPT_GROUP_ID, "group_id=%u"},
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700415 {OPT_DEFAULT_PERMISSIONS, "default_permissions"},
416 {OPT_ALLOW_OTHER, "allow_other"},
Miklos Szeredidb50b962005-09-09 13:10:33 -0700417 {OPT_MAX_READ, "max_read=%u"},
Miklos Szeredid8091612006-12-06 20:35:48 -0800418 {OPT_BLKSIZE, "blksize=%u"},
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700419 {OPT_ERR, NULL}
420};
421
Miklos Szeredid8091612006-12-06 20:35:48 -0800422static int parse_fuse_opt(char *opt, struct fuse_mount_data *d, int is_bdev)
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700423{
424 char *p;
425 memset(d, 0, sizeof(struct fuse_mount_data));
Miklos Szeredidb50b962005-09-09 13:10:33 -0700426 d->max_read = ~0;
Miklos Szeredid1875db2008-02-08 04:21:43 -0800427 d->blksize = FUSE_DEFAULT_BLKSIZE;
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700428
429 while ((p = strsep(&opt, ",")) != NULL) {
430 int token;
431 int value;
432 substring_t args[MAX_OPT_ARGS];
433 if (!*p)
434 continue;
435
436 token = match_token(p, tokens, args);
437 switch (token) {
438 case OPT_FD:
439 if (match_int(&args[0], &value))
440 return 0;
441 d->fd = value;
Miklos Szeredi5a533682005-09-09 13:10:34 -0700442 d->fd_present = 1;
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700443 break;
444
445 case OPT_ROOTMODE:
446 if (match_octal(&args[0], &value))
447 return 0;
Timo Savolaa5bfffa2007-04-08 16:04:00 -0700448 if (!fuse_valid_type(value))
449 return 0;
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700450 d->rootmode = value;
Miklos Szeredi5a533682005-09-09 13:10:34 -0700451 d->rootmode_present = 1;
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700452 break;
453
454 case OPT_USER_ID:
455 if (match_int(&args[0], &value))
456 return 0;
457 d->user_id = value;
Miklos Szeredi5a533682005-09-09 13:10:34 -0700458 d->user_id_present = 1;
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700459 break;
460
Miklos Szeredi87729a52005-09-09 13:10:34 -0700461 case OPT_GROUP_ID:
462 if (match_int(&args[0], &value))
463 return 0;
464 d->group_id = value;
Miklos Szeredi5a533682005-09-09 13:10:34 -0700465 d->group_id_present = 1;
Miklos Szeredi87729a52005-09-09 13:10:34 -0700466 break;
467
Miklos Szeredi1e9a4ed2005-09-09 13:10:31 -0700468 case OPT_DEFAULT_PERMISSIONS:
469 d->flags |= FUSE_DEFAULT_PERMISSIONS;
470 break;
471
472 case OPT_ALLOW_OTHER:
473 d->flags |= FUSE_ALLOW_OTHER;
474 break;
475
Miklos Szeredidb50b962005-09-09 13:10:33 -0700476 case OPT_MAX_READ:
477 if (match_int(&args[0], &value))
478 return 0;
479 d->max_read = value;
480 break;
481
Miklos Szeredid8091612006-12-06 20:35:48 -0800482 case OPT_BLKSIZE:
483 if (!is_bdev || match_int(&args[0], &value))
484 return 0;
485 d->blksize = value;
486 break;
487
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700488 default:
489 return 0;
490 }
491 }
Miklos Szeredi5a533682005-09-09 13:10:34 -0700492
493 if (!d->fd_present || !d->rootmode_present ||
494 !d->user_id_present || !d->group_id_present)
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700495 return 0;
496
497 return 1;
498}
499
Al Viro34c80b12011-12-08 21:32:45 -0500500static int fuse_show_options(struct seq_file *m, struct dentry *root)
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700501{
Al Viro34c80b12011-12-08 21:32:45 -0500502 struct super_block *sb = root->d_sb;
503 struct fuse_conn *fc = get_fuse_conn_super(sb);
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700504
505 seq_printf(m, ",user_id=%u", fc->user_id);
Miklos Szeredi87729a52005-09-09 13:10:34 -0700506 seq_printf(m, ",group_id=%u", fc->group_id);
Miklos Szeredi1e9a4ed2005-09-09 13:10:31 -0700507 if (fc->flags & FUSE_DEFAULT_PERMISSIONS)
508 seq_puts(m, ",default_permissions");
509 if (fc->flags & FUSE_ALLOW_OTHER)
510 seq_puts(m, ",allow_other");
Miklos Szeredidb50b962005-09-09 13:10:33 -0700511 if (fc->max_read != ~0)
512 seq_printf(m, ",max_read=%u", fc->max_read);
Al Viro34c80b12011-12-08 21:32:45 -0500513 if (sb->s_bdev && sb->s_blocksize != FUSE_DEFAULT_BLKSIZE)
514 seq_printf(m, ",blksize=%lu", sb->s_blocksize);
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700515 return 0;
516}
517
Tejun Heoa325f9b2009-04-14 10:54:52 +0900518void fuse_conn_init(struct fuse_conn *fc)
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700519{
Tejun Heo0d179aa2008-11-26 12:03:55 +0100520 memset(fc, 0, sizeof(*fc));
521 spin_lock_init(&fc->lock);
522 mutex_init(&fc->inst_mutex);
John Muir3b463ae2009-05-31 11:13:57 -0400523 init_rwsem(&fc->killsb);
Tejun Heo0d179aa2008-11-26 12:03:55 +0100524 atomic_set(&fc->count, 1);
525 init_waitqueue_head(&fc->waitq);
526 init_waitqueue_head(&fc->blocked_waitq);
527 init_waitqueue_head(&fc->reserved_req_waitq);
528 INIT_LIST_HEAD(&fc->pending);
529 INIT_LIST_HEAD(&fc->processing);
530 INIT_LIST_HEAD(&fc->io);
531 INIT_LIST_HEAD(&fc->interrupts);
532 INIT_LIST_HEAD(&fc->bg_queue);
533 INIT_LIST_HEAD(&fc->entry);
Miklos Szeredi07e77dc2010-12-07 20:16:56 +0100534 fc->forget_list_tail = &fc->forget_list_head;
Tejun Heo0d179aa2008-11-26 12:03:55 +0100535 atomic_set(&fc->num_waiting, 0);
Csaba Henk7a6d3c82009-07-01 17:28:41 -0700536 fc->max_background = FUSE_DEFAULT_MAX_BACKGROUND;
537 fc->congestion_threshold = FUSE_DEFAULT_CONGESTION_THRESHOLD;
Tejun Heo0d179aa2008-11-26 12:03:55 +0100538 fc->khctr = 0;
539 fc->polled_files = RB_ROOT;
Tejun Heo0d179aa2008-11-26 12:03:55 +0100540 fc->reqctr = 0;
541 fc->blocked = 1;
542 fc->attr_version = 1;
543 get_random_bytes(&fc->scramble_key, sizeof(fc->scramble_key));
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700544}
Tejun Heo0d179aa2008-11-26 12:03:55 +0100545EXPORT_SYMBOL_GPL(fuse_conn_init);
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700546
Miklos Szeredibafa9652006-06-25 05:48:51 -0700547void fuse_conn_put(struct fuse_conn *fc)
548{
Miklos Szeredid2a85162006-10-17 00:10:11 -0700549 if (atomic_dec_and_test(&fc->count)) {
Miklos Szeredi0ec7ca42006-12-06 20:35:52 -0800550 if (fc->destroy_req)
551 fuse_request_free(fc->destroy_req);
Miklos Szeredid2a85162006-10-17 00:10:11 -0700552 mutex_destroy(&fc->inst_mutex);
Tejun Heo43901aa2008-11-26 12:03:56 +0100553 fc->release(fc);
Miklos Szeredid2a85162006-10-17 00:10:11 -0700554 }
Miklos Szeredibafa9652006-06-25 05:48:51 -0700555}
Tejun Heo08cbf542009-04-14 10:54:53 +0900556EXPORT_SYMBOL_GPL(fuse_conn_put);
Miklos Szeredibafa9652006-06-25 05:48:51 -0700557
558struct fuse_conn *fuse_conn_get(struct fuse_conn *fc)
559{
560 atomic_inc(&fc->count);
561 return fc;
562}
Tejun Heo08cbf542009-04-14 10:54:53 +0900563EXPORT_SYMBOL_GPL(fuse_conn_get);
Miklos Szeredibafa9652006-06-25 05:48:51 -0700564
Tejun Heob93f8582008-11-26 12:03:55 +0100565static struct inode *fuse_get_root_inode(struct super_block *sb, unsigned mode)
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700566{
567 struct fuse_attr attr;
568 memset(&attr, 0, sizeof(attr));
569
570 attr.mode = mode;
571 attr.ino = FUSE_ROOT_ID;
Miklos Szeredi074406f2007-10-16 23:31:02 -0700572 attr.nlink = 1;
Miklos Szeredi1fb69e72007-10-18 03:06:58 -0700573 return fuse_iget(sb, 1, 0, &attr, 0, 0);
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700574}
575
Miklos Szeredi1729a162008-11-26 12:03:54 +0100576struct fuse_inode_handle {
Miklos Szeredidbd561d2008-07-25 01:49:00 -0700577 u64 nodeid;
578 u32 generation;
579};
580
581static struct dentry *fuse_get_dentry(struct super_block *sb,
582 struct fuse_inode_handle *handle)
583{
Miklos Szeredi33670fa2008-07-25 01:49:02 -0700584 struct fuse_conn *fc = get_fuse_conn_super(sb);
Miklos Szeredidbd561d2008-07-25 01:49:00 -0700585 struct inode *inode;
586 struct dentry *entry;
587 int err = -ESTALE;
588
589 if (handle->nodeid == 0)
590 goto out_err;
591
592 inode = ilookup5(sb, handle->nodeid, fuse_inode_eq, &handle->nodeid);
Miklos Szeredi33670fa2008-07-25 01:49:02 -0700593 if (!inode) {
594 struct fuse_entry_out outarg;
595 struct qstr name;
596
597 if (!fc->export_support)
598 goto out_err;
599
600 name.len = 1;
601 name.name = ".";
602 err = fuse_lookup_name(sb, handle->nodeid, &name, &outarg,
603 &inode);
604 if (err && err != -ENOENT)
605 goto out_err;
606 if (err || !inode) {
607 err = -ESTALE;
608 goto out_err;
609 }
610 err = -EIO;
611 if (get_node_id(inode) != handle->nodeid)
612 goto out_iput;
613 }
Miklos Szeredidbd561d2008-07-25 01:49:00 -0700614 err = -ESTALE;
615 if (inode->i_generation != handle->generation)
616 goto out_iput;
617
Christoph Hellwig44003722008-08-11 15:49:04 +0200618 entry = d_obtain_alias(inode);
Al Viroc35eebe2010-12-18 11:15:22 -0500619 if (!IS_ERR(entry) && get_node_id(inode) != FUSE_ROOT_ID)
Miklos Szeredidbd561d2008-07-25 01:49:00 -0700620 fuse_invalidate_entry_cache(entry);
Miklos Szeredidbd561d2008-07-25 01:49:00 -0700621
622 return entry;
623
624 out_iput:
625 iput(inode);
626 out_err:
627 return ERR_PTR(err);
628}
629
630static int fuse_encode_fh(struct dentry *dentry, u32 *fh, int *max_len,
631 int connectable)
632{
633 struct inode *inode = dentry->d_inode;
634 bool encode_parent = connectable && !S_ISDIR(inode->i_mode);
635 int len = encode_parent ? 6 : 3;
636 u64 nodeid;
637 u32 generation;
638
Aneesh Kumar K.V5fe0c232011-01-29 18:43:25 +0530639 if (*max_len < len) {
640 *max_len = len;
Miklos Szeredidbd561d2008-07-25 01:49:00 -0700641 return 255;
Aneesh Kumar K.V5fe0c232011-01-29 18:43:25 +0530642 }
Miklos Szeredidbd561d2008-07-25 01:49:00 -0700643
644 nodeid = get_fuse_inode(inode)->nodeid;
645 generation = inode->i_generation;
646
647 fh[0] = (u32)(nodeid >> 32);
648 fh[1] = (u32)(nodeid & 0xffffffff);
649 fh[2] = generation;
650
651 if (encode_parent) {
652 struct inode *parent;
653
654 spin_lock(&dentry->d_lock);
655 parent = dentry->d_parent->d_inode;
656 nodeid = get_fuse_inode(parent)->nodeid;
657 generation = parent->i_generation;
658 spin_unlock(&dentry->d_lock);
659
660 fh[3] = (u32)(nodeid >> 32);
661 fh[4] = (u32)(nodeid & 0xffffffff);
662 fh[5] = generation;
663 }
664
665 *max_len = len;
666 return encode_parent ? 0x82 : 0x81;
667}
668
669static struct dentry *fuse_fh_to_dentry(struct super_block *sb,
670 struct fid *fid, int fh_len, int fh_type)
671{
672 struct fuse_inode_handle handle;
673
674 if ((fh_type != 0x81 && fh_type != 0x82) || fh_len < 3)
675 return NULL;
676
677 handle.nodeid = (u64) fid->raw[0] << 32;
678 handle.nodeid |= (u64) fid->raw[1];
679 handle.generation = fid->raw[2];
680 return fuse_get_dentry(sb, &handle);
681}
682
683static struct dentry *fuse_fh_to_parent(struct super_block *sb,
684 struct fid *fid, int fh_len, int fh_type)
685{
686 struct fuse_inode_handle parent;
687
688 if (fh_type != 0x82 || fh_len < 6)
689 return NULL;
690
691 parent.nodeid = (u64) fid->raw[3] << 32;
692 parent.nodeid |= (u64) fid->raw[4];
693 parent.generation = fid->raw[5];
694 return fuse_get_dentry(sb, &parent);
695}
696
Miklos Szeredi33670fa2008-07-25 01:49:02 -0700697static struct dentry *fuse_get_parent(struct dentry *child)
698{
699 struct inode *child_inode = child->d_inode;
700 struct fuse_conn *fc = get_fuse_conn(child_inode);
701 struct inode *inode;
702 struct dentry *parent;
703 struct fuse_entry_out outarg;
704 struct qstr name;
705 int err;
706
707 if (!fc->export_support)
708 return ERR_PTR(-ESTALE);
709
710 name.len = 2;
711 name.name = "..";
712 err = fuse_lookup_name(child_inode->i_sb, get_node_id(child_inode),
713 &name, &outarg, &inode);
Christoph Hellwig44003722008-08-11 15:49:04 +0200714 if (err) {
715 if (err == -ENOENT)
716 return ERR_PTR(-ESTALE);
Miklos Szeredi33670fa2008-07-25 01:49:02 -0700717 return ERR_PTR(err);
Miklos Szeredi33670fa2008-07-25 01:49:02 -0700718 }
Christoph Hellwig44003722008-08-11 15:49:04 +0200719
720 parent = d_obtain_alias(inode);
Al Viroc35eebe2010-12-18 11:15:22 -0500721 if (!IS_ERR(parent) && get_node_id(inode) != FUSE_ROOT_ID)
Miklos Szeredi33670fa2008-07-25 01:49:02 -0700722 fuse_invalidate_entry_cache(parent);
Miklos Szeredi33670fa2008-07-25 01:49:02 -0700723
724 return parent;
725}
Miklos Szeredidbd561d2008-07-25 01:49:00 -0700726
727static const struct export_operations fuse_export_operations = {
728 .fh_to_dentry = fuse_fh_to_dentry,
729 .fh_to_parent = fuse_fh_to_parent,
730 .encode_fh = fuse_encode_fh,
Miklos Szeredi33670fa2008-07-25 01:49:02 -0700731 .get_parent = fuse_get_parent,
Miklos Szeredidbd561d2008-07-25 01:49:00 -0700732};
733
Josef 'Jeff' Sipekee9b6d62007-02-12 00:55:41 -0800734static const struct super_operations fuse_super_operations = {
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700735 .alloc_inode = fuse_alloc_inode,
736 .destroy_inode = fuse_destroy_inode,
Al Virob57922d2010-06-07 14:34:48 -0400737 .evict_inode = fuse_evict_inode,
Miklos Szerediead5f0b2007-05-23 13:57:54 -0700738 .drop_inode = generic_delete_inode,
Miklos Szeredi71421252006-06-25 05:48:52 -0700739 .remount_fs = fuse_remount_fs,
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700740 .put_super = fuse_put_super,
Miklos Szeredi69a53bf2006-01-16 22:14:41 -0800741 .umount_begin = fuse_umount_begin,
Miklos Szeredie5e55582005-09-09 13:10:28 -0700742 .statfs = fuse_statfs,
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700743 .show_options = fuse_show_options,
744};
745
Csaba Henk487ea5a2009-08-26 19:17:22 +0200746static void sanitize_global_limit(unsigned *limit)
747{
748 if (*limit == 0)
749 *limit = ((num_physpages << PAGE_SHIFT) >> 13) /
750 sizeof(struct fuse_req);
751
752 if (*limit >= 1 << 16)
753 *limit = (1 << 16) - 1;
754}
755
756static int set_global_limit(const char *val, struct kernel_param *kp)
757{
758 int rv;
759
760 rv = param_set_uint(val, kp);
761 if (rv)
762 return rv;
763
764 sanitize_global_limit((unsigned *)kp->arg);
765
766 return 0;
767}
768
769static void process_init_limits(struct fuse_conn *fc, struct fuse_init_out *arg)
770{
771 int cap_sys_admin = capable(CAP_SYS_ADMIN);
772
773 if (arg->minor < 13)
774 return;
775
776 sanitize_global_limit(&max_user_bgreq);
777 sanitize_global_limit(&max_user_congthresh);
778
779 if (arg->max_background) {
780 fc->max_background = arg->max_background;
781
782 if (!cap_sys_admin && fc->max_background > max_user_bgreq)
783 fc->max_background = max_user_bgreq;
784 }
785 if (arg->congestion_threshold) {
786 fc->congestion_threshold = arg->congestion_threshold;
787
788 if (!cap_sys_admin &&
789 fc->congestion_threshold > max_user_congthresh)
790 fc->congestion_threshold = max_user_congthresh;
791 }
792}
793
Miklos Szeredi9b9a0462006-01-16 22:14:44 -0800794static void process_init_reply(struct fuse_conn *fc, struct fuse_req *req)
795{
Miklos Szeredi9b9a0462006-01-16 22:14:44 -0800796 struct fuse_init_out *arg = &req->misc.init_out;
797
798 if (req->out.h.error || arg->major != FUSE_KERNEL_VERSION)
799 fc->conn_error = 1;
800 else {
Miklos Szeredi9cd68452006-02-01 03:04:40 -0800801 unsigned long ra_pages;
802
Csaba Henk487ea5a2009-08-26 19:17:22 +0200803 process_init_limits(fc, arg);
804
Miklos Szeredi9cd68452006-02-01 03:04:40 -0800805 if (arg->minor >= 6) {
806 ra_pages = arg->max_readahead / PAGE_CACHE_SIZE;
807 if (arg->flags & FUSE_ASYNC_READ)
808 fc->async_read = 1;
Miklos Szeredi71421252006-06-25 05:48:52 -0700809 if (!(arg->flags & FUSE_POSIX_LOCKS))
810 fc->no_lock = 1;
Miklos Szeredi37fb3a32011-08-08 16:08:08 +0200811 if (arg->minor >= 17) {
812 if (!(arg->flags & FUSE_FLOCK_LOCKS))
813 fc->no_flock = 1;
Miklos Szeredi24114502011-09-12 09:31:49 +0200814 } else {
815 if (!(arg->flags & FUSE_POSIX_LOCKS))
816 fc->no_flock = 1;
Miklos Szeredi37fb3a32011-08-08 16:08:08 +0200817 }
Miklos Szeredi6ff958e2007-10-18 03:07:02 -0700818 if (arg->flags & FUSE_ATOMIC_O_TRUNC)
819 fc->atomic_o_trunc = 1;
Miklos Szeredi33670fa2008-07-25 01:49:02 -0700820 if (arg->minor >= 9) {
821 /* LOOKUP has dependency on proto version */
822 if (arg->flags & FUSE_EXPORT_SUPPORT)
823 fc->export_support = 1;
824 }
Miklos Szeredi78bb6cb2008-05-12 14:02:32 -0700825 if (arg->flags & FUSE_BIG_WRITES)
826 fc->big_writes = 1;
Miklos Szeredie0a43dd2009-06-30 20:12:23 +0200827 if (arg->flags & FUSE_DONT_MASK)
828 fc->dont_mask = 1;
Miklos Szeredi71421252006-06-25 05:48:52 -0700829 } else {
Miklos Szeredi9cd68452006-02-01 03:04:40 -0800830 ra_pages = fc->max_read / PAGE_CACHE_SIZE;
Miklos Szeredi71421252006-06-25 05:48:52 -0700831 fc->no_lock = 1;
Miklos Szeredi37fb3a32011-08-08 16:08:08 +0200832 fc->no_flock = 1;
Miklos Szeredi71421252006-06-25 05:48:52 -0700833 }
Miklos Szeredi9cd68452006-02-01 03:04:40 -0800834
835 fc->bdi.ra_pages = min(fc->bdi.ra_pages, ra_pages);
Miklos Szeredi9b9a0462006-01-16 22:14:44 -0800836 fc->minor = arg->minor;
837 fc->max_write = arg->minor < 5 ? 4096 : arg->max_write;
Miklos Szeredif948d562008-06-17 18:05:40 +0200838 fc->max_write = max_t(unsigned, 4096, fc->max_write);
Miklos Szeredi0ec7ca42006-12-06 20:35:52 -0800839 fc->conn_init = 1;
Miklos Szeredi9b9a0462006-01-16 22:14:44 -0800840 }
Miklos Szeredi08a53cd2006-04-10 22:54:59 -0700841 fc->blocked = 0;
842 wake_up_all(&fc->blocked_waitq);
Miklos Szeredi9b9a0462006-01-16 22:14:44 -0800843}
844
Miklos Szeredice1d5a42006-04-10 22:54:58 -0700845static void fuse_send_init(struct fuse_conn *fc, struct fuse_req *req)
Miklos Szeredi9b9a0462006-01-16 22:14:44 -0800846{
Miklos Szeredi9b9a0462006-01-16 22:14:44 -0800847 struct fuse_init_in *arg = &req->misc.init_in;
Miklos Szeredi095da6c2006-01-16 22:14:52 -0800848
Miklos Szeredi9b9a0462006-01-16 22:14:44 -0800849 arg->major = FUSE_KERNEL_VERSION;
850 arg->minor = FUSE_KERNEL_MINOR_VERSION;
Miklos Szeredi9cd68452006-02-01 03:04:40 -0800851 arg->max_readahead = fc->bdi.ra_pages * PAGE_CACHE_SIZE;
Miklos Szeredi78bb6cb2008-05-12 14:02:32 -0700852 arg->flags |= FUSE_ASYNC_READ | FUSE_POSIX_LOCKS | FUSE_ATOMIC_O_TRUNC |
Miklos Szeredi37fb3a32011-08-08 16:08:08 +0200853 FUSE_EXPORT_SUPPORT | FUSE_BIG_WRITES | FUSE_DONT_MASK |
854 FUSE_FLOCK_LOCKS;
Miklos Szeredi9b9a0462006-01-16 22:14:44 -0800855 req->in.h.opcode = FUSE_INIT;
856 req->in.numargs = 1;
857 req->in.args[0].size = sizeof(*arg);
858 req->in.args[0].value = arg;
859 req->out.numargs = 1;
Daniel Mack3ad2f3f2010-02-03 08:01:28 +0800860 /* Variable length argument used for backward compatibility
Miklos Szeredi9b9a0462006-01-16 22:14:44 -0800861 with interface version < 7.5. Rest of init_out is zeroed
862 by do_get_request(), so a short reply is not a problem */
863 req->out.argvar = 1;
864 req->out.args[0].size = sizeof(struct fuse_init_out);
865 req->out.args[0].value = &req->misc.init_out;
866 req->end = process_init_reply;
Tejun Heob93f8582008-11-26 12:03:55 +0100867 fuse_request_send_background(fc, req);
Miklos Szeredi9b9a0462006-01-16 22:14:44 -0800868}
869
Tejun Heo43901aa2008-11-26 12:03:56 +0100870static void fuse_free_conn(struct fuse_conn *fc)
871{
872 kfree(fc);
873}
874
Tejun Heoa325f9b2009-04-14 10:54:52 +0900875static int fuse_bdi_init(struct fuse_conn *fc, struct super_block *sb)
876{
877 int err;
878
Jens Axboed9938312009-06-12 14:45:52 +0200879 fc->bdi.name = "fuse";
Tejun Heoa325f9b2009-04-14 10:54:52 +0900880 fc->bdi.ra_pages = (VM_MAX_READAHEAD * 1024) / PAGE_CACHE_SIZE;
Tejun Heoa325f9b2009-04-14 10:54:52 +0900881 /* fuse does it's own writeback accounting */
882 fc->bdi.capabilities = BDI_CAP_NO_ACCT_WB;
883
884 err = bdi_init(&fc->bdi);
885 if (err)
886 return err;
887
888 fc->bdi_initialized = 1;
889
890 if (sb->s_bdev) {
891 err = bdi_register(&fc->bdi, NULL, "%u:%u-fuseblk",
892 MAJOR(fc->dev), MINOR(fc->dev));
893 } else {
894 err = bdi_register_dev(&fc->bdi, fc->dev);
895 }
896
897 if (err)
898 return err;
899
900 /*
901 * For a single fuse filesystem use max 1% of dirty +
902 * writeback threshold.
903 *
904 * This gives about 1M of write buffer for memory maps on a
905 * machine with 1G and 10% dirty_ratio, which should be more
906 * than enough.
907 *
908 * Privileged users can raise it by writing to
909 *
910 * /sys/class/bdi/<bdi>/max_ratio
911 */
912 bdi_set_max_ratio(&fc->bdi, 1);
913
914 return 0;
915}
916
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700917static int fuse_fill_super(struct super_block *sb, void *data, int silent)
918{
919 struct fuse_conn *fc;
920 struct inode *root;
921 struct fuse_mount_data d;
922 struct file *file;
Miklos Szeredif543f252006-01-16 22:14:35 -0800923 struct dentry *root_dentry;
Miklos Szeredice1d5a42006-04-10 22:54:58 -0700924 struct fuse_req *init_req;
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700925 int err;
Miklos Szeredid8091612006-12-06 20:35:48 -0800926 int is_bdev = sb->s_bdev != NULL;
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700927
Miklos Szeredic2b8f002009-01-26 15:00:58 +0100928 err = -EINVAL;
Miklos Szeredi71421252006-06-25 05:48:52 -0700929 if (sb->s_flags & MS_MANDLOCK)
Miklos Szeredic2b8f002009-01-26 15:00:58 +0100930 goto err;
Miklos Szeredi71421252006-06-25 05:48:52 -0700931
Al Viro9e1f1de2011-06-03 18:24:58 -0400932 sb->s_flags &= ~MS_NOSEC;
933
Miklos Szeredid8091612006-12-06 20:35:48 -0800934 if (!parse_fuse_opt((char *) data, &d, is_bdev))
Miklos Szeredic2b8f002009-01-26 15:00:58 +0100935 goto err;
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700936
Miklos Szeredid8091612006-12-06 20:35:48 -0800937 if (is_bdev) {
Miklos Szeredi875d95e2006-12-06 20:35:54 -0800938#ifdef CONFIG_BLOCK
Miklos Szeredic2b8f002009-01-26 15:00:58 +0100939 err = -EINVAL;
Miklos Szeredid8091612006-12-06 20:35:48 -0800940 if (!sb_set_blocksize(sb, d.blksize))
Miklos Szeredic2b8f002009-01-26 15:00:58 +0100941 goto err;
Miklos Szeredi875d95e2006-12-06 20:35:54 -0800942#endif
Miklos Szeredid8091612006-12-06 20:35:48 -0800943 } else {
944 sb->s_blocksize = PAGE_CACHE_SIZE;
945 sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
946 }
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700947 sb->s_magic = FUSE_SUPER_MAGIC;
948 sb->s_op = &fuse_super_operations;
949 sb->s_maxbytes = MAX_LFS_FILESIZE;
Miklos Szeredi0a2da9b2012-04-11 11:45:06 +0200950 sb->s_time_gran = 1;
Miklos Szeredidbd561d2008-07-25 01:49:00 -0700951 sb->s_export_op = &fuse_export_operations;
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700952
953 file = fget(d.fd);
Miklos Szeredic2b8f002009-01-26 15:00:58 +0100954 err = -EINVAL;
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700955 if (!file)
Miklos Szeredic2b8f002009-01-26 15:00:58 +0100956 goto err;
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700957
Miklos Szeredic2b8f002009-01-26 15:00:58 +0100958 if (file->f_op != &fuse_dev_operations)
959 goto err_fput;
Miklos Szeredi0720b312006-04-10 22:54:55 -0700960
Tejun Heo0d179aa2008-11-26 12:03:55 +0100961 fc = kmalloc(sizeof(*fc), GFP_KERNEL);
Miklos Szeredic2b8f002009-01-26 15:00:58 +0100962 err = -ENOMEM;
963 if (!fc)
964 goto err_fput;
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700965
Tejun Heoa325f9b2009-04-14 10:54:52 +0900966 fuse_conn_init(fc);
967
968 fc->dev = sb->s_dev;
John Muir3b463ae2009-05-31 11:13:57 -0400969 fc->sb = sb;
Tejun Heoa325f9b2009-04-14 10:54:52 +0900970 err = fuse_bdi_init(fc, sb);
971 if (err)
972 goto err_put_conn;
Tejun Heo0d179aa2008-11-26 12:03:55 +0100973
Jens Axboe32a88aa2009-09-16 15:02:33 +0200974 sb->s_bdi = &fc->bdi;
975
Miklos Szeredie0a43dd2009-06-30 20:12:23 +0200976 /* Handle umasking inside the fuse code */
977 if (sb->s_flags & MS_POSIXACL)
978 fc->dont_mask = 1;
979 sb->s_flags |= MS_POSIXACL;
980
Tejun Heo43901aa2008-11-26 12:03:56 +0100981 fc->release = fuse_free_conn;
Miklos Szeredi1e9a4ed2005-09-09 13:10:31 -0700982 fc->flags = d.flags;
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700983 fc->user_id = d.user_id;
Miklos Szeredi87729a52005-09-09 13:10:34 -0700984 fc->group_id = d.group_id;
Miklos Szeredif948d562008-06-17 18:05:40 +0200985 fc->max_read = max_t(unsigned, 4096, d.max_read);
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700986
Miklos Szeredif543f252006-01-16 22:14:35 -0800987 /* Used by get_root_inode() */
988 sb->s_fs_info = fc;
989
Miklos Szeredid8a5ba42005-09-09 13:10:26 -0700990 err = -ENOMEM;
Tejun Heob93f8582008-11-26 12:03:55 +0100991 root = fuse_get_root_inode(sb, d.rootmode);
Al Viro48fde702012-01-08 22:15:13 -0500992 root_dentry = d_make_root(root);
993 if (!root_dentry)
Miklos Szeredic2b8f002009-01-26 15:00:58 +0100994 goto err_put_conn;
Al Viroc35eebe2010-12-18 11:15:22 -0500995 /* only now - we want root dentry with NULL ->d_op */
996 sb->s_d_op = &fuse_dentry_operations;
Miklos Szeredif543f252006-01-16 22:14:35 -0800997
Miklos Szeredice1d5a42006-04-10 22:54:58 -0700998 init_req = fuse_request_alloc();
999 if (!init_req)
1000 goto err_put_root;
1001
Miklos Szeredi0ec7ca42006-12-06 20:35:52 -08001002 if (is_bdev) {
1003 fc->destroy_req = fuse_request_alloc();
1004 if (!fc->destroy_req)
Julia Lawall17e18ab2008-10-16 16:08:56 +02001005 goto err_free_init_req;
Miklos Szeredi0ec7ca42006-12-06 20:35:52 -08001006 }
1007
Miklos Szeredibafa9652006-06-25 05:48:51 -07001008 mutex_lock(&fuse_mutex);
Miklos Szeredi8aa09a52006-04-26 10:49:16 +02001009 err = -EINVAL;
1010 if (file->private_data)
Miklos Szeredibafa9652006-06-25 05:48:51 -07001011 goto err_unlock;
Miklos Szeredi8aa09a52006-04-26 10:49:16 +02001012
Miklos Szeredibafa9652006-06-25 05:48:51 -07001013 err = fuse_ctl_add_conn(fc);
1014 if (err)
1015 goto err_unlock;
1016
1017 list_add_tail(&fc->entry, &fuse_conn_list);
Miklos Szeredif543f252006-01-16 22:14:35 -08001018 sb->s_root = root_dentry;
Miklos Szeredif543f252006-01-16 22:14:35 -08001019 fc->connected = 1;
Miklos Szeredibafa9652006-06-25 05:48:51 -07001020 file->private_data = fuse_conn_get(fc);
1021 mutex_unlock(&fuse_mutex);
Miklos Szeredi0720b312006-04-10 22:54:55 -07001022 /*
1023 * atomic_dec_and_test() in fput() provides the necessary
1024 * memory barrier for file->private_data to be visible on all
1025 * CPUs after this
1026 */
1027 fput(file);
Miklos Szeredif543f252006-01-16 22:14:35 -08001028
Miklos Szeredice1d5a42006-04-10 22:54:58 -07001029 fuse_send_init(fc, init_req);
Miklos Szeredif543f252006-01-16 22:14:35 -08001030
Miklos Szeredid8a5ba42005-09-09 13:10:26 -07001031 return 0;
1032
Miklos Szeredibafa9652006-06-25 05:48:51 -07001033 err_unlock:
1034 mutex_unlock(&fuse_mutex);
Julia Lawall17e18ab2008-10-16 16:08:56 +02001035 err_free_init_req:
Miklos Szeredice1d5a42006-04-10 22:54:58 -07001036 fuse_request_free(init_req);
Miklos Szeredif543f252006-01-16 22:14:35 -08001037 err_put_root:
1038 dput(root_dentry);
Miklos Szeredic2b8f002009-01-26 15:00:58 +01001039 err_put_conn:
Tejun Heoa325f9b2009-04-14 10:54:52 +09001040 fuse_bdi_destroy(fc);
Miklos Szeredibafa9652006-06-25 05:48:51 -07001041 fuse_conn_put(fc);
Miklos Szeredic2b8f002009-01-26 15:00:58 +01001042 err_fput:
1043 fput(file);
1044 err:
Miklos Szeredid8a5ba42005-09-09 13:10:26 -07001045 return err;
1046}
1047
Al Viro3c26ff62010-07-25 11:46:36 +04001048static struct dentry *fuse_mount(struct file_system_type *fs_type,
David Howells454e2392006-06-23 02:02:57 -07001049 int flags, const char *dev_name,
Al Viro3c26ff62010-07-25 11:46:36 +04001050 void *raw_data)
Miklos Szeredid8a5ba42005-09-09 13:10:26 -07001051{
Al Viro3c26ff62010-07-25 11:46:36 +04001052 return mount_nodev(fs_type, flags, raw_data, fuse_fill_super);
Miklos Szeredid8a5ba42005-09-09 13:10:26 -07001053}
1054
John Muir3b463ae2009-05-31 11:13:57 -04001055static void fuse_kill_sb_anon(struct super_block *sb)
1056{
1057 struct fuse_conn *fc = get_fuse_conn_super(sb);
1058
1059 if (fc) {
1060 down_write(&fc->killsb);
1061 fc->sb = NULL;
1062 up_write(&fc->killsb);
1063 }
1064
1065 kill_anon_super(sb);
1066}
1067
Miklos Szeredi875d95e2006-12-06 20:35:54 -08001068static struct file_system_type fuse_fs_type = {
1069 .owner = THIS_MODULE,
1070 .name = "fuse",
Miklos Szeredi79c0b2d2007-05-08 00:25:43 -07001071 .fs_flags = FS_HAS_SUBTYPE,
Al Viro3c26ff62010-07-25 11:46:36 +04001072 .mount = fuse_mount,
John Muir3b463ae2009-05-31 11:13:57 -04001073 .kill_sb = fuse_kill_sb_anon,
Miklos Szeredi875d95e2006-12-06 20:35:54 -08001074};
1075
1076#ifdef CONFIG_BLOCK
Al Viro152a0832010-07-25 00:46:55 +04001077static struct dentry *fuse_mount_blk(struct file_system_type *fs_type,
Miklos Szeredid6392f82006-12-06 20:35:44 -08001078 int flags, const char *dev_name,
Al Viro152a0832010-07-25 00:46:55 +04001079 void *raw_data)
Miklos Szeredid6392f82006-12-06 20:35:44 -08001080{
Al Viro152a0832010-07-25 00:46:55 +04001081 return mount_bdev(fs_type, flags, dev_name, raw_data, fuse_fill_super);
Miklos Szeredid6392f82006-12-06 20:35:44 -08001082}
1083
John Muir3b463ae2009-05-31 11:13:57 -04001084static void fuse_kill_sb_blk(struct super_block *sb)
1085{
1086 struct fuse_conn *fc = get_fuse_conn_super(sb);
1087
1088 if (fc) {
1089 down_write(&fc->killsb);
1090 fc->sb = NULL;
1091 up_write(&fc->killsb);
1092 }
1093
1094 kill_block_super(sb);
1095}
1096
Miklos Szeredid6392f82006-12-06 20:35:44 -08001097static struct file_system_type fuseblk_fs_type = {
1098 .owner = THIS_MODULE,
1099 .name = "fuseblk",
Al Viro152a0832010-07-25 00:46:55 +04001100 .mount = fuse_mount_blk,
John Muir3b463ae2009-05-31 11:13:57 -04001101 .kill_sb = fuse_kill_sb_blk,
Alexey Dobriyanedad01e2007-06-16 10:16:05 -07001102 .fs_flags = FS_REQUIRES_DEV | FS_HAS_SUBTYPE,
Miklos Szeredid6392f82006-12-06 20:35:44 -08001103};
1104
Miklos Szeredi875d95e2006-12-06 20:35:54 -08001105static inline int register_fuseblk(void)
1106{
1107 return register_filesystem(&fuseblk_fs_type);
1108}
1109
1110static inline void unregister_fuseblk(void)
1111{
1112 unregister_filesystem(&fuseblk_fs_type);
1113}
1114#else
1115static inline int register_fuseblk(void)
1116{
1117 return 0;
1118}
1119
1120static inline void unregister_fuseblk(void)
1121{
1122}
1123#endif
1124
Alexey Dobriyan51cc5062008-07-25 19:45:34 -07001125static void fuse_inode_init_once(void *foo)
Miklos Szeredid8a5ba42005-09-09 13:10:26 -07001126{
Miklos Szeredi1729a162008-11-26 12:03:54 +01001127 struct inode *inode = foo;
Miklos Szeredid8a5ba42005-09-09 13:10:26 -07001128
Christoph Lametera35afb82007-05-16 22:10:57 -07001129 inode_init_once(inode);
Miklos Szeredid8a5ba42005-09-09 13:10:26 -07001130}
1131
1132static int __init fuse_fs_init(void)
1133{
1134 int err;
1135
Miklos Szeredid6392f82006-12-06 20:35:44 -08001136 fuse_inode_cachep = kmem_cache_create("fuse_inode",
1137 sizeof(struct fuse_inode),
1138 0, SLAB_HWCACHE_ALIGN,
Paul Mundt20c2df82007-07-20 10:11:58 +09001139 fuse_inode_init_once);
Miklos Szeredid6392f82006-12-06 20:35:44 -08001140 err = -ENOMEM;
1141 if (!fuse_inode_cachep)
Al Viro988f0322011-12-13 12:25:27 -05001142 goto out;
1143
1144 err = register_fuseblk();
1145 if (err)
1146 goto out2;
1147
1148 err = register_filesystem(&fuse_fs_type);
1149 if (err)
1150 goto out3;
Miklos Szeredid6392f82006-12-06 20:35:44 -08001151
1152 return 0;
1153
Al Viro988f0322011-12-13 12:25:27 -05001154 out3:
Miklos Szeredi875d95e2006-12-06 20:35:54 -08001155 unregister_fuseblk();
Al Viro988f0322011-12-13 12:25:27 -05001156 out2:
1157 kmem_cache_destroy(fuse_inode_cachep);
Miklos Szeredid6392f82006-12-06 20:35:44 -08001158 out:
Miklos Szeredid8a5ba42005-09-09 13:10:26 -07001159 return err;
1160}
1161
1162static void fuse_fs_cleanup(void)
1163{
1164 unregister_filesystem(&fuse_fs_type);
Miklos Szeredi875d95e2006-12-06 20:35:54 -08001165 unregister_fuseblk();
Miklos Szeredid8a5ba42005-09-09 13:10:26 -07001166 kmem_cache_destroy(fuse_inode_cachep);
1167}
1168
Greg Kroah-Hartman5c89e172007-10-29 20:13:17 +01001169static struct kobject *fuse_kobj;
1170static struct kobject *connections_kobj;
1171
Miklos Szeredif543f252006-01-16 22:14:35 -08001172static int fuse_sysfs_init(void)
1173{
1174 int err;
1175
Greg Kroah-Hartman00d26662007-10-29 14:17:23 -06001176 fuse_kobj = kobject_create_and_add("fuse", fs_kobj);
Greg Kroah-Hartman5c89e172007-10-29 20:13:17 +01001177 if (!fuse_kobj) {
1178 err = -ENOMEM;
Miklos Szeredif543f252006-01-16 22:14:35 -08001179 goto out_err;
Greg Kroah-Hartman5c89e172007-10-29 20:13:17 +01001180 }
Miklos Szeredif543f252006-01-16 22:14:35 -08001181
Greg Kroah-Hartman5c89e172007-10-29 20:13:17 +01001182 connections_kobj = kobject_create_and_add("connections", fuse_kobj);
1183 if (!connections_kobj) {
1184 err = -ENOMEM;
Miklos Szeredif543f252006-01-16 22:14:35 -08001185 goto out_fuse_unregister;
Greg Kroah-Hartman5c89e172007-10-29 20:13:17 +01001186 }
Miklos Szeredif543f252006-01-16 22:14:35 -08001187
1188 return 0;
1189
1190 out_fuse_unregister:
Greg Kroah-Hartman197b12d2007-12-20 08:13:05 -08001191 kobject_put(fuse_kobj);
Miklos Szeredif543f252006-01-16 22:14:35 -08001192 out_err:
1193 return err;
1194}
1195
1196static void fuse_sysfs_cleanup(void)
1197{
Greg Kroah-Hartman197b12d2007-12-20 08:13:05 -08001198 kobject_put(connections_kobj);
1199 kobject_put(fuse_kobj);
Miklos Szeredif543f252006-01-16 22:14:35 -08001200}
1201
Miklos Szeredid8a5ba42005-09-09 13:10:26 -07001202static int __init fuse_init(void)
1203{
1204 int res;
1205
Miklos Szeredi1729a162008-11-26 12:03:54 +01001206 printk(KERN_INFO "fuse init (API version %i.%i)\n",
Miklos Szeredid8a5ba42005-09-09 13:10:26 -07001207 FUSE_KERNEL_VERSION, FUSE_KERNEL_MINOR_VERSION);
1208
Miklos Szeredibafa9652006-06-25 05:48:51 -07001209 INIT_LIST_HEAD(&fuse_conn_list);
Miklos Szeredid8a5ba42005-09-09 13:10:26 -07001210 res = fuse_fs_init();
1211 if (res)
1212 goto err;
1213
Miklos Szeredi334f4852005-09-09 13:10:27 -07001214 res = fuse_dev_init();
1215 if (res)
1216 goto err_fs_cleanup;
1217
Miklos Szeredif543f252006-01-16 22:14:35 -08001218 res = fuse_sysfs_init();
1219 if (res)
1220 goto err_dev_cleanup;
1221
Miklos Szeredibafa9652006-06-25 05:48:51 -07001222 res = fuse_ctl_init();
1223 if (res)
1224 goto err_sysfs_cleanup;
1225
Csaba Henk487ea5a2009-08-26 19:17:22 +02001226 sanitize_global_limit(&max_user_bgreq);
1227 sanitize_global_limit(&max_user_congthresh);
1228
Miklos Szeredid8a5ba42005-09-09 13:10:26 -07001229 return 0;
1230
Miklos Szeredibafa9652006-06-25 05:48:51 -07001231 err_sysfs_cleanup:
1232 fuse_sysfs_cleanup();
Miklos Szeredif543f252006-01-16 22:14:35 -08001233 err_dev_cleanup:
1234 fuse_dev_cleanup();
Miklos Szeredi334f4852005-09-09 13:10:27 -07001235 err_fs_cleanup:
1236 fuse_fs_cleanup();
Miklos Szeredid8a5ba42005-09-09 13:10:26 -07001237 err:
1238 return res;
1239}
1240
1241static void __exit fuse_exit(void)
1242{
1243 printk(KERN_DEBUG "fuse exit\n");
1244
Miklos Szeredibafa9652006-06-25 05:48:51 -07001245 fuse_ctl_cleanup();
Miklos Szeredif543f252006-01-16 22:14:35 -08001246 fuse_sysfs_cleanup();
Miklos Szeredid8a5ba42005-09-09 13:10:26 -07001247 fuse_fs_cleanup();
Miklos Szeredi334f4852005-09-09 13:10:27 -07001248 fuse_dev_cleanup();
Miklos Szeredid8a5ba42005-09-09 13:10:26 -07001249}
1250
1251module_init(fuse_init);
1252module_exit(fuse_exit);