xref: /freebsd/sys/fs/fuse/fuse_file.c (revision 80ff58b89dcacfe07fe20b045890df9db5ca0af0)
1 /*
2  * Copyright (c) 2007-2009 Google Inc. and Amit Singh
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions are
7  * met:
8  *
9  * * Redistributions of source code must retain the above copyright
10  *   notice, this list of conditions and the following disclaimer.
11  * * Redistributions in binary form must reproduce the above
12  *   copyright notice, this list of conditions and the following disclaimer
13  *   in the documentation and/or other materials provided with the
14  *   distribution.
15  * * Neither the name of Google Inc. nor the names of its
16  *   contributors may be used to endorse or promote products derived from
17  *   this software without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
22  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
23  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
24  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
25  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
29  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30  *
31  * Copyright (C) 2005 Csaba Henk.
32  * All rights reserved.
33  *
34  * Redistribution and use in source and binary forms, with or without
35  * modification, are permitted provided that the following conditions
36  * are met:
37  * 1. Redistributions of source code must retain the above copyright
38  *    notice, this list of conditions and the following disclaimer.
39  * 2. Redistributions in binary form must reproduce the above copyright
40  *    notice, this list of conditions and the following disclaimer in the
41  *    documentation and/or other materials provided with the distribution.
42  *
43  * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
44  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
45  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
46  * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
47  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
48  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
49  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
50  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
51  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
52  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
53  * SUCH DAMAGE.
54  */
55 
56 #include <sys/cdefs.h>
57 __FBSDID("$FreeBSD$");
58 
59 #include <sys/types.h>
60 #include <sys/module.h>
61 #include <sys/systm.h>
62 #include <sys/errno.h>
63 #include <sys/param.h>
64 #include <sys/kernel.h>
65 #include <sys/conf.h>
66 #include <sys/uio.h>
67 #include <sys/malloc.h>
68 #include <sys/queue.h>
69 #include <sys/lock.h>
70 #include <sys/sx.h>
71 #include <sys/mutex.h>
72 #include <sys/proc.h>
73 #include <sys/mount.h>
74 #include <sys/vnode.h>
75 #include <sys/sysctl.h>
76 
77 #include "fuse.h"
78 #include "fuse_file.h"
79 #include "fuse_internal.h"
80 #include "fuse_ipc.h"
81 #include "fuse_node.h"
82 
83 #define FUSE_DEBUG_MODULE FILE
84 #include "fuse_debug.h"
85 
86 static int fuse_fh_count = 0;
87 
88 SYSCTL_INT(_vfs_fuse, OID_AUTO, filehandle_count, CTLFLAG_RD,
89     &fuse_fh_count, 0, "");
90 
91 int
92 fuse_filehandle_open(struct vnode *vp,
93     fufh_type_t fufh_type,
94     struct fuse_filehandle **fufhp,
95     struct thread *td,
96     struct ucred *cred)
97 {
98 	struct fuse_dispatcher fdi;
99 	struct fuse_open_in *foi;
100 	struct fuse_open_out *foo;
101 
102 	int err = 0;
103 	int isdir = 0;
104 	int oflags = 0;
105 	int op = FUSE_OPEN;
106 
107 	fuse_trace_printf("fuse_filehandle_open(vp=%p, fufh_type=%d)\n",
108 	    vp, fufh_type);
109 
110 	if (fuse_filehandle_valid(vp, fufh_type)) {
111 		panic("FUSE: filehandle_open called despite valid fufh (type=%d)",
112 		    fufh_type);
113 		/* NOTREACHED */
114 	}
115 	/*
116          * Note that this means we are effectively FILTERING OUT open() flags.
117          */
118 	oflags = fuse_filehandle_xlate_to_oflags(fufh_type);
119 
120 	if (vnode_isdir(vp)) {
121 		isdir = 1;
122 		op = FUSE_OPENDIR;
123 		if (fufh_type != FUFH_RDONLY) {
124 			printf("FUSE:non-rdonly fh requested for a directory?\n");
125 			fufh_type = FUFH_RDONLY;
126 		}
127 	}
128 	fdisp_init(&fdi, sizeof(*foi));
129 	fdisp_make_vp(&fdi, op, vp, td, cred);
130 
131 	foi = fdi.indata;
132 	foi->flags = oflags;
133 
134 	if ((err = fdisp_wait_answ(&fdi))) {
135 		debug_printf("OUCH ... daemon didn't give fh (err = %d)\n", err);
136 		if (err == ENOENT) {
137 			fuse_internal_vnode_disappear(vp);
138 		}
139 		goto out;
140 	}
141 	foo = fdi.answ;
142 
143 	fuse_filehandle_init(vp, fufh_type, fufhp, foo->fh);
144 	fuse_vnode_open(vp, foo->open_flags, td);
145 
146 out:
147 	fdisp_destroy(&fdi);
148 	return err;
149 }
150 
151 int
152 fuse_filehandle_close(struct vnode *vp,
153     fufh_type_t fufh_type,
154     struct thread *td,
155     struct ucred *cred)
156 {
157 	struct fuse_dispatcher fdi;
158 	struct fuse_release_in *fri;
159 	struct fuse_vnode_data *fvdat = VTOFUD(vp);
160 	struct fuse_filehandle *fufh = NULL;
161 
162 	int err = 0;
163 	int isdir = 0;
164 	int op = FUSE_RELEASE;
165 
166 	fuse_trace_printf("fuse_filehandle_put(vp=%p, fufh_type=%d)\n",
167 	    vp, fufh_type);
168 
169 	fufh = &(fvdat->fufh[fufh_type]);
170 	if (!FUFH_IS_VALID(fufh)) {
171 		panic("FUSE: filehandle_put called on invalid fufh (type=%d)",
172 		    fufh_type);
173 		/* NOTREACHED */
174 	}
175 	if (fuse_isdeadfs(vp)) {
176 		goto out;
177 	}
178 	if (vnode_isdir(vp)) {
179 		op = FUSE_RELEASEDIR;
180 		isdir = 1;
181 	}
182 	fdisp_init(&fdi, sizeof(*fri));
183 	fdisp_make_vp(&fdi, op, vp, td, cred);
184 	fri = fdi.indata;
185 	fri->fh = fufh->fh_id;
186 	fri->flags = fuse_filehandle_xlate_to_oflags(fufh_type);
187 
188 	err = fdisp_wait_answ(&fdi);
189 	fdisp_destroy(&fdi);
190 
191 out:
192 	atomic_subtract_acq_int(&fuse_fh_count, 1);
193 	fufh->fh_id = (uint64_t)-1;
194 	fufh->fh_type = FUFH_INVALID;
195 
196 	return err;
197 }
198 
199 int
200 fuse_filehandle_valid(struct vnode *vp, fufh_type_t fufh_type)
201 {
202 	struct fuse_vnode_data *fvdat = VTOFUD(vp);
203 	struct fuse_filehandle *fufh;
204 
205 	fufh = &(fvdat->fufh[fufh_type]);
206 	return FUFH_IS_VALID(fufh);
207 }
208 
209 int
210 fuse_filehandle_get(struct vnode *vp, fufh_type_t fufh_type,
211     struct fuse_filehandle **fufhp)
212 {
213 	struct fuse_vnode_data *fvdat = VTOFUD(vp);
214 	struct fuse_filehandle *fufh;
215 
216 	fufh = &(fvdat->fufh[fufh_type]);
217 	if (!FUFH_IS_VALID(fufh))
218 		return EBADF;
219 	if (fufhp != NULL)
220 		*fufhp = fufh;
221 	return 0;
222 }
223 
224 int
225 fuse_filehandle_getrw(struct vnode *vp, fufh_type_t fufh_type,
226     struct fuse_filehandle **fufhp)
227 {
228 	struct fuse_vnode_data *fvdat = VTOFUD(vp);
229 	struct fuse_filehandle *fufh;
230 
231 	fufh = &(fvdat->fufh[fufh_type]);
232 	if (!FUFH_IS_VALID(fufh)) {
233 		fufh_type = FUFH_RDWR;
234 	}
235 	return fuse_filehandle_get(vp, fufh_type, fufhp);
236 }
237 
238 void
239 fuse_filehandle_init(struct vnode *vp,
240     fufh_type_t fufh_type,
241     struct fuse_filehandle **fufhp,
242     uint64_t fh_id)
243 {
244 	struct fuse_vnode_data *fvdat = VTOFUD(vp);
245 	struct fuse_filehandle *fufh;
246 
247 	FS_DEBUG("id=%jd type=%d\n", (intmax_t)fh_id, fufh_type);
248 	fufh = &(fvdat->fufh[fufh_type]);
249 	MPASS(!FUFH_IS_VALID(fufh));
250 	fufh->fh_id = fh_id;
251 	fufh->fh_type = fufh_type;
252 	if (!FUFH_IS_VALID(fufh)) {
253 		panic("FUSE: init: invalid filehandle id (type=%d)", fufh_type);
254 	}
255 	if (fufhp != NULL)
256 		*fufhp = fufh;
257 
258 	atomic_add_acq_int(&fuse_fh_count, 1);
259 }
260