xref: /freebsd/sys/fs/fuse/fuse_node.c (revision b2d48be1bc7df45ddd13b143a160d0acb5a383c5)
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/vnode.h>
74 #include <sys/namei.h>
75 #include <sys/mount.h>
76 #include <sys/sysctl.h>
77 #include <sys/fcntl.h>
78 #include <sys/fnv_hash.h>
79 #include <sys/priv.h>
80 #include <security/mac/mac_framework.h>
81 #include <vm/vm.h>
82 #include <vm/vm_extern.h>
83 
84 #include "fuse.h"
85 #include "fuse_node.h"
86 #include "fuse_internal.h"
87 #include "fuse_io.h"
88 #include "fuse_ipc.h"
89 
90 #define FUSE_DEBUG_MODULE VNOPS
91 #include "fuse_debug.h"
92 
93 MALLOC_DEFINE(M_FUSEVN, "fuse_vnode", "fuse vnode private data");
94 
95 static int fuse_node_count = 0;
96 
97 SYSCTL_INT(_vfs_fuse, OID_AUTO, node_count, CTLFLAG_RD,
98     &fuse_node_count, 0, "");
99 
100 int	fuse_data_cache_enable = 1;
101 
102 SYSCTL_INT(_vfs_fuse, OID_AUTO, data_cache_enable, CTLFLAG_RW,
103     &fuse_data_cache_enable, 0, "");
104 
105 int	fuse_data_cache_invalidate = 0;
106 
107 SYSCTL_INT(_vfs_fuse, OID_AUTO, data_cache_invalidate, CTLFLAG_RW,
108     &fuse_data_cache_invalidate, 0, "");
109 
110 int	fuse_mmap_enable = 1;
111 
112 SYSCTL_INT(_vfs_fuse, OID_AUTO, mmap_enable, CTLFLAG_RW,
113     &fuse_mmap_enable, 0, "");
114 
115 int	fuse_refresh_size = 0;
116 
117 SYSCTL_INT(_vfs_fuse, OID_AUTO, refresh_size, CTLFLAG_RW,
118     &fuse_refresh_size, 0, "");
119 
120 int	fuse_sync_resize = 1;
121 
122 SYSCTL_INT(_vfs_fuse, OID_AUTO, sync_resize, CTLFLAG_RW,
123     &fuse_sync_resize, 0, "");
124 
125 int	fuse_fix_broken_io = 0;
126 
127 SYSCTL_INT(_vfs_fuse, OID_AUTO, fix_broken_io, CTLFLAG_RW,
128     &fuse_fix_broken_io, 0, "");
129 
130 static void
131 fuse_vnode_init(struct vnode *vp, struct fuse_vnode_data *fvdat,
132     uint64_t nodeid, enum vtype vtyp)
133 {
134 	int i;
135 
136 	fvdat->nid = nodeid;
137 	if (nodeid == FUSE_ROOT_ID) {
138 		vp->v_vflag |= VV_ROOT;
139 	}
140 	vp->v_type = vtyp;
141 	vp->v_data = fvdat;
142 
143 	for (i = 0; i < FUFH_MAXTYPE; i++)
144 		fvdat->fufh[i].fh_type = FUFH_INVALID;
145 
146 	atomic_add_acq_int(&fuse_node_count, 1);
147 }
148 
149 void
150 fuse_vnode_destroy(struct vnode *vp)
151 {
152 	struct fuse_vnode_data *fvdat = vp->v_data;
153 
154 	vp->v_data = NULL;
155 	free(fvdat, M_FUSEVN);
156 
157 	atomic_subtract_acq_int(&fuse_node_count, 1);
158 }
159 
160 static int
161 fuse_vnode_cmp(struct vnode *vp, void *nidp)
162 {
163 	return (VTOI(vp) != *((uint64_t *)nidp));
164 }
165 
166 static uint32_t __inline
167 fuse_vnode_hash(uint64_t id)
168 {
169 	return (fnv_32_buf(&id, sizeof(id), FNV1_32_INIT));
170 }
171 
172 static int
173 fuse_vnode_alloc(struct mount *mp,
174     struct thread *td,
175     uint64_t nodeid,
176     enum vtype vtyp,
177     struct vnode **vpp)
178 {
179 	struct fuse_vnode_data *fvdat;
180 	struct vnode *vp2;
181 	int err = 0;
182 
183 	FS_DEBUG("been asked for vno #%ju\n", (uintmax_t)nodeid);
184 
185 	if (vtyp == VNON) {
186 		return EINVAL;
187 	}
188 	*vpp = NULL;
189 	err = vfs_hash_get(mp, fuse_vnode_hash(nodeid), LK_EXCLUSIVE, td, vpp,
190 	    fuse_vnode_cmp, &nodeid);
191 	if (err)
192 		return (err);
193 
194 	if (*vpp) {
195 		MPASS((*vpp)->v_type == vtyp && (*vpp)->v_data != NULL);
196 		FS_DEBUG("vnode taken from hash\n");
197 		return (0);
198 	}
199 	fvdat = malloc(sizeof(*fvdat), M_FUSEVN, M_WAITOK | M_ZERO);
200 	err = getnewvnode("fuse", mp, &fuse_vnops, vpp);
201 	if (err) {
202 		free(fvdat, M_FUSEVN);
203 		return (err);
204 	}
205 	lockmgr((*vpp)->v_vnlock, LK_EXCLUSIVE, NULL);
206 	fuse_vnode_init(*vpp, fvdat, nodeid, vtyp);
207 	err = insmntque(*vpp, mp);
208 	ASSERT_VOP_ELOCKED(*vpp, "fuse_vnode_alloc");
209 	if (err) {
210 		free(fvdat, M_FUSEVN);
211 		*vpp = NULL;
212 		return (err);
213 	}
214 	err = vfs_hash_insert(*vpp, fuse_vnode_hash(nodeid), LK_EXCLUSIVE,
215 	    td, &vp2, fuse_vnode_cmp, &nodeid);
216 	if (err)
217 		return (err);
218 	if (vp2 != NULL) {
219 		*vpp = vp2;
220 		return (0);
221 	}
222 
223 	ASSERT_VOP_ELOCKED(*vpp, "fuse_vnode_alloc");
224 
225 	return (0);
226 }
227 
228 int
229 fuse_vnode_get(struct mount *mp,
230     uint64_t nodeid,
231     struct vnode *dvp,
232     struct vnode **vpp,
233     struct componentname *cnp,
234     enum vtype vtyp)
235 {
236 	struct thread *td = (cnp != NULL ? cnp->cn_thread : curthread);
237 	int err = 0;
238 
239 	debug_printf("dvp=%p\n", dvp);
240 
241 	err = fuse_vnode_alloc(mp, td, nodeid, vtyp, vpp);
242 	if (err) {
243 		return err;
244 	}
245 	if (dvp != NULL) {
246 		MPASS((cnp->cn_flags & ISDOTDOT) == 0);
247 		MPASS(!(cnp->cn_namelen == 1 && cnp->cn_nameptr[0] == '.'));
248 		fuse_vnode_setparent(*vpp, dvp);
249 	}
250 	if (dvp != NULL && cnp != NULL && (cnp->cn_flags & MAKEENTRY) != 0) {
251 		ASSERT_VOP_LOCKED(*vpp, "fuse_vnode_get");
252 		ASSERT_VOP_LOCKED(dvp, "fuse_vnode_get");
253 		cache_enter(dvp, *vpp, cnp);
254 	}
255 
256 	/*
257 	 * In userland, libfuse uses cached lookups for dot and dotdot entries,
258 	 * thus it does not really bump the nlookup counter for forget.
259 	 * Follow the same semantic and avoid tu bump it in order to keep
260 	 * nlookup counters consistent.
261 	 */
262 	if (cnp == NULL || ((cnp->cn_flags & ISDOTDOT) == 0 &&
263 	    (cnp->cn_namelen != 1 || cnp->cn_nameptr[0] != '.')))
264 		VTOFUD(*vpp)->nlookup++;
265 
266 	return 0;
267 }
268 
269 void
270 fuse_vnode_open(struct vnode *vp, int32_t fuse_open_flags, struct thread *td)
271 {
272 	/*
273 	 * Funcation is called for every vnode open.
274 	 * Merge fuse_open_flags it may be 0
275 	 *
276 	 * XXXIP: Handle FOPEN_KEEP_CACHE
277 	 */
278 	/*
279 	 * Ideally speaking, direct io should be enabled on
280 	 * fd's but do not see of any way of providing that
281 	 * this implementation.
282 	 *
283 	 * Also cannot think of a reason why would two
284 	 * different fd's on same vnode would like
285 	 * have DIRECT_IO turned on and off. But linux
286 	 * based implementation works on an fd not an
287 	 * inode and provides such a feature.
288 	 *
289 	 * XXXIP: Handle fd based DIRECT_IO
290 	 */
291 	if (fuse_open_flags & FOPEN_DIRECT_IO) {
292 		VTOFUD(vp)->flag |= FN_DIRECTIO;
293 	} else {
294 	        VTOFUD(vp)->flag &= ~FN_DIRECTIO;
295 	}
296 
297 	if (vnode_vtype(vp) == VREG) {
298 		/* XXXIP prevent getattr, by using cached node size */
299 		vnode_create_vobject(vp, 0, td);
300 	}
301 }
302 
303 int
304 fuse_vnode_savesize(struct vnode *vp, struct ucred *cred)
305 {
306 	struct fuse_vnode_data *fvdat = VTOFUD(vp);
307 	struct thread *td = curthread;
308 	struct fuse_filehandle *fufh = NULL;
309 	struct fuse_dispatcher fdi;
310 	struct fuse_setattr_in *fsai;
311 	int err = 0;
312 
313 	FS_DEBUG("inode=%ju size=%ju\n", (uintmax_t)VTOI(vp),
314 	    (uintmax_t)fvdat->filesize);
315 	ASSERT_VOP_ELOCKED(vp, "fuse_io_extend");
316 
317 	if (fuse_isdeadfs(vp)) {
318 		return EBADF;
319 	}
320 	if (vnode_vtype(vp) == VDIR) {
321 		return EISDIR;
322 	}
323 	if (vfs_isrdonly(vnode_mount(vp))) {
324 		return EROFS;
325 	}
326 	if (cred == NULL) {
327 		cred = td->td_ucred;
328 	}
329 	fdisp_init(&fdi, sizeof(*fsai));
330 	fdisp_make_vp(&fdi, FUSE_SETATTR, vp, td, cred);
331 	fsai = fdi.indata;
332 	fsai->valid = 0;
333 
334 	/* Truncate to a new value. */
335 	    fsai->size = fvdat->filesize;
336 	fsai->valid |= FATTR_SIZE;
337 
338 	fuse_filehandle_getrw(vp, FUFH_WRONLY, &fufh);
339 	if (fufh) {
340 		fsai->fh = fufh->fh_id;
341 		fsai->valid |= FATTR_FH;
342 	}
343 	err = fdisp_wait_answ(&fdi);
344 	fdisp_destroy(&fdi);
345 	if (err == 0)
346 		fvdat->flag &= ~FN_SIZECHANGE;
347 
348 	return err;
349 }
350 
351 void
352 fuse_vnode_refreshsize(struct vnode *vp, struct ucred *cred)
353 {
354 
355 	struct fuse_vnode_data *fvdat = VTOFUD(vp);
356 	struct vattr va;
357 
358 	if ((fvdat->flag & FN_SIZECHANGE) != 0 ||
359 	    (fuse_refresh_size == 0 && fvdat->filesize != 0))
360 		return;
361 
362 	VOP_GETATTR(vp, &va, cred);
363 	FS_DEBUG("refreshed file size: %jd\n", (intmax_t)VTOFUD(vp)->filesize);
364 }
365 
366 int
367 fuse_vnode_setsize(struct vnode *vp, struct ucred *cred, off_t newsize)
368 {
369 	struct fuse_vnode_data *fvdat = VTOFUD(vp);
370 	off_t oldsize;
371 	int err = 0;
372 
373 	FS_DEBUG("inode=%ju oldsize=%ju newsize=%ju\n",
374 	    (uintmax_t)VTOI(vp), (uintmax_t)fvdat->filesize,
375 	    (uintmax_t)newsize);
376 	ASSERT_VOP_ELOCKED(vp, "fuse_vnode_setsize");
377 
378 	oldsize = fvdat->filesize;
379 	fvdat->filesize = newsize;
380 	fvdat->flag |= FN_SIZECHANGE;
381 
382 	if (newsize < oldsize) {
383 		err = vtruncbuf(vp, cred, newsize, fuse_iosize(vp));
384 	}
385 	vnode_pager_setsize(vp, newsize);
386 	return err;
387 }
388