xref: /freebsd/sys/fs/fuse/fuse_node.c (revision 4f52dfbb8d6c4d446500c5b097e3806ec219fbd4)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 2007-2009 Google Inc. and Amit Singh
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions are
9  * met:
10  *
11  * * Redistributions of source code must retain the above copyright
12  *   notice, this list of conditions and the following disclaimer.
13  * * Redistributions in binary form must reproduce the above
14  *   copyright notice, this list of conditions and the following disclaimer
15  *   in the documentation and/or other materials provided with the
16  *   distribution.
17  * * Neither the name of Google Inc. nor the names of its
18  *   contributors may be used to endorse or promote products derived from
19  *   this software without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
24  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
25  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
26  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
27  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
31  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  *
33  * Copyright (C) 2005 Csaba Henk.
34  * All rights reserved.
35  *
36  * Redistribution and use in source and binary forms, with or without
37  * modification, are permitted provided that the following conditions
38  * are met:
39  * 1. Redistributions of source code must retain the above copyright
40  *    notice, this list of conditions and the following disclaimer.
41  * 2. Redistributions in binary form must reproduce the above copyright
42  *    notice, this list of conditions and the following disclaimer in the
43  *    documentation and/or other materials provided with the distribution.
44  *
45  * THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND
46  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
47  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
48  * ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
49  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
50  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
51  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
52  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
53  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
54  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
55  * SUCH DAMAGE.
56  */
57 
58 #include <sys/cdefs.h>
59 __FBSDID("$FreeBSD$");
60 
61 #include <sys/types.h>
62 #include <sys/module.h>
63 #include <sys/systm.h>
64 #include <sys/errno.h>
65 #include <sys/param.h>
66 #include <sys/kernel.h>
67 #include <sys/conf.h>
68 #include <sys/uio.h>
69 #include <sys/malloc.h>
70 #include <sys/queue.h>
71 #include <sys/lock.h>
72 #include <sys/sx.h>
73 #include <sys/mutex.h>
74 #include <sys/proc.h>
75 #include <sys/vnode.h>
76 #include <sys/namei.h>
77 #include <sys/mount.h>
78 #include <sys/sysctl.h>
79 #include <sys/fcntl.h>
80 #include <sys/fnv_hash.h>
81 #include <sys/priv.h>
82 #include <security/mac/mac_framework.h>
83 #include <vm/vm.h>
84 #include <vm/vm_extern.h>
85 
86 #include "fuse.h"
87 #include "fuse_node.h"
88 #include "fuse_internal.h"
89 #include "fuse_io.h"
90 #include "fuse_ipc.h"
91 
92 #define FUSE_DEBUG_MODULE VNOPS
93 #include "fuse_debug.h"
94 
95 MALLOC_DEFINE(M_FUSEVN, "fuse_vnode", "fuse vnode private data");
96 
97 static int fuse_node_count = 0;
98 
99 SYSCTL_INT(_vfs_fuse, OID_AUTO, node_count, CTLFLAG_RD,
100     &fuse_node_count, 0, "");
101 
102 int	fuse_data_cache_enable = 1;
103 
104 SYSCTL_INT(_vfs_fuse, OID_AUTO, data_cache_enable, CTLFLAG_RW,
105     &fuse_data_cache_enable, 0, "");
106 
107 int	fuse_data_cache_invalidate = 0;
108 
109 SYSCTL_INT(_vfs_fuse, OID_AUTO, data_cache_invalidate, CTLFLAG_RW,
110     &fuse_data_cache_invalidate, 0, "");
111 
112 int	fuse_mmap_enable = 1;
113 
114 SYSCTL_INT(_vfs_fuse, OID_AUTO, mmap_enable, CTLFLAG_RW,
115     &fuse_mmap_enable, 0, "");
116 
117 int	fuse_refresh_size = 0;
118 
119 SYSCTL_INT(_vfs_fuse, OID_AUTO, refresh_size, CTLFLAG_RW,
120     &fuse_refresh_size, 0, "");
121 
122 int	fuse_sync_resize = 1;
123 
124 SYSCTL_INT(_vfs_fuse, OID_AUTO, sync_resize, CTLFLAG_RW,
125     &fuse_sync_resize, 0, "");
126 
127 int	fuse_fix_broken_io = 0;
128 
129 SYSCTL_INT(_vfs_fuse, OID_AUTO, fix_broken_io, CTLFLAG_RW,
130     &fuse_fix_broken_io, 0, "");
131 
132 static void
133 fuse_vnode_init(struct vnode *vp, struct fuse_vnode_data *fvdat,
134     uint64_t nodeid, enum vtype vtyp)
135 {
136 	int i;
137 
138 	fvdat->nid = nodeid;
139 	if (nodeid == FUSE_ROOT_ID) {
140 		vp->v_vflag |= VV_ROOT;
141 	}
142 	vp->v_type = vtyp;
143 	vp->v_data = fvdat;
144 
145 	for (i = 0; i < FUFH_MAXTYPE; i++)
146 		fvdat->fufh[i].fh_type = FUFH_INVALID;
147 
148 	atomic_add_acq_int(&fuse_node_count, 1);
149 }
150 
151 void
152 fuse_vnode_destroy(struct vnode *vp)
153 {
154 	struct fuse_vnode_data *fvdat = vp->v_data;
155 
156 	vp->v_data = NULL;
157 	free(fvdat, M_FUSEVN);
158 
159 	atomic_subtract_acq_int(&fuse_node_count, 1);
160 }
161 
162 static int
163 fuse_vnode_cmp(struct vnode *vp, void *nidp)
164 {
165 	return (VTOI(vp) != *((uint64_t *)nidp));
166 }
167 
168 static uint32_t __inline
169 fuse_vnode_hash(uint64_t id)
170 {
171 	return (fnv_32_buf(&id, sizeof(id), FNV1_32_INIT));
172 }
173 
174 static int
175 fuse_vnode_alloc(struct mount *mp,
176     struct thread *td,
177     uint64_t nodeid,
178     enum vtype vtyp,
179     struct vnode **vpp)
180 {
181 	struct fuse_vnode_data *fvdat;
182 	struct vnode *vp2;
183 	int err = 0;
184 
185 	FS_DEBUG("been asked for vno #%ju\n", (uintmax_t)nodeid);
186 
187 	if (vtyp == VNON) {
188 		return EINVAL;
189 	}
190 	*vpp = NULL;
191 	err = vfs_hash_get(mp, fuse_vnode_hash(nodeid), LK_EXCLUSIVE, td, vpp,
192 	    fuse_vnode_cmp, &nodeid);
193 	if (err)
194 		return (err);
195 
196 	if (*vpp) {
197 		MPASS((*vpp)->v_type == vtyp && (*vpp)->v_data != NULL);
198 		FS_DEBUG("vnode taken from hash\n");
199 		return (0);
200 	}
201 	fvdat = malloc(sizeof(*fvdat), M_FUSEVN, M_WAITOK | M_ZERO);
202 	err = getnewvnode("fuse", mp, &fuse_vnops, vpp);
203 	if (err) {
204 		free(fvdat, M_FUSEVN);
205 		return (err);
206 	}
207 	lockmgr((*vpp)->v_vnlock, LK_EXCLUSIVE, NULL);
208 	fuse_vnode_init(*vpp, fvdat, nodeid, vtyp);
209 	err = insmntque(*vpp, mp);
210 	ASSERT_VOP_ELOCKED(*vpp, "fuse_vnode_alloc");
211 	if (err) {
212 		free(fvdat, M_FUSEVN);
213 		*vpp = NULL;
214 		return (err);
215 	}
216 	err = vfs_hash_insert(*vpp, fuse_vnode_hash(nodeid), LK_EXCLUSIVE,
217 	    td, &vp2, fuse_vnode_cmp, &nodeid);
218 	if (err)
219 		return (err);
220 	if (vp2 != NULL) {
221 		*vpp = vp2;
222 		return (0);
223 	}
224 
225 	ASSERT_VOP_ELOCKED(*vpp, "fuse_vnode_alloc");
226 
227 	return (0);
228 }
229 
230 int
231 fuse_vnode_get(struct mount *mp,
232     uint64_t nodeid,
233     struct vnode *dvp,
234     struct vnode **vpp,
235     struct componentname *cnp,
236     enum vtype vtyp)
237 {
238 	struct thread *td = (cnp != NULL ? cnp->cn_thread : curthread);
239 	int err = 0;
240 
241 	debug_printf("dvp=%p\n", dvp);
242 
243 	err = fuse_vnode_alloc(mp, td, nodeid, vtyp, vpp);
244 	if (err) {
245 		return err;
246 	}
247 	if (dvp != NULL) {
248 		MPASS((cnp->cn_flags & ISDOTDOT) == 0);
249 		MPASS(!(cnp->cn_namelen == 1 && cnp->cn_nameptr[0] == '.'));
250 		fuse_vnode_setparent(*vpp, dvp);
251 	}
252 	if (dvp != NULL && cnp != NULL && (cnp->cn_flags & MAKEENTRY) != 0) {
253 		ASSERT_VOP_LOCKED(*vpp, "fuse_vnode_get");
254 		ASSERT_VOP_LOCKED(dvp, "fuse_vnode_get");
255 		cache_enter(dvp, *vpp, cnp);
256 	}
257 
258 	/*
259 	 * In userland, libfuse uses cached lookups for dot and dotdot entries,
260 	 * thus it does not really bump the nlookup counter for forget.
261 	 * Follow the same semantic and avoid tu bump it in order to keep
262 	 * nlookup counters consistent.
263 	 */
264 	if (cnp == NULL || ((cnp->cn_flags & ISDOTDOT) == 0 &&
265 	    (cnp->cn_namelen != 1 || cnp->cn_nameptr[0] != '.')))
266 		VTOFUD(*vpp)->nlookup++;
267 
268 	return 0;
269 }
270 
271 void
272 fuse_vnode_open(struct vnode *vp, int32_t fuse_open_flags, struct thread *td)
273 {
274 	/*
275 	 * Funcation is called for every vnode open.
276 	 * Merge fuse_open_flags it may be 0
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 		ASSERT_VOP_ELOCKED(vp, __func__);
293 		VTOFUD(vp)->flag |= FN_DIRECTIO;
294 		fuse_io_invalbuf(vp, td);
295 	} else {
296 		if ((fuse_open_flags & FOPEN_KEEP_CACHE) == 0)
297 			fuse_io_invalbuf(vp, td);
298 	        VTOFUD(vp)->flag &= ~FN_DIRECTIO;
299 	}
300 
301 	if (vnode_vtype(vp) == VREG) {
302 		/* XXXIP prevent getattr, by using cached node size */
303 		vnode_create_vobject(vp, 0, td);
304 	}
305 }
306 
307 int
308 fuse_vnode_savesize(struct vnode *vp, struct ucred *cred)
309 {
310 	struct fuse_vnode_data *fvdat = VTOFUD(vp);
311 	struct thread *td = curthread;
312 	struct fuse_filehandle *fufh = NULL;
313 	struct fuse_dispatcher fdi;
314 	struct fuse_setattr_in *fsai;
315 	int err = 0;
316 
317 	FS_DEBUG("inode=%ju size=%ju\n", (uintmax_t)VTOI(vp),
318 	    (uintmax_t)fvdat->filesize);
319 	ASSERT_VOP_ELOCKED(vp, "fuse_io_extend");
320 
321 	if (fuse_isdeadfs(vp)) {
322 		return EBADF;
323 	}
324 	if (vnode_vtype(vp) == VDIR) {
325 		return EISDIR;
326 	}
327 	if (vfs_isrdonly(vnode_mount(vp))) {
328 		return EROFS;
329 	}
330 	if (cred == NULL) {
331 		cred = td->td_ucred;
332 	}
333 	fdisp_init(&fdi, sizeof(*fsai));
334 	fdisp_make_vp(&fdi, FUSE_SETATTR, vp, td, cred);
335 	fsai = fdi.indata;
336 	fsai->valid = 0;
337 
338 	/* Truncate to a new value. */
339 	    fsai->size = fvdat->filesize;
340 	fsai->valid |= FATTR_SIZE;
341 
342 	fuse_filehandle_getrw(vp, FUFH_WRONLY, &fufh);
343 	if (fufh) {
344 		fsai->fh = fufh->fh_id;
345 		fsai->valid |= FATTR_FH;
346 	}
347 	err = fdisp_wait_answ(&fdi);
348 	fdisp_destroy(&fdi);
349 	if (err == 0)
350 		fvdat->flag &= ~FN_SIZECHANGE;
351 
352 	return err;
353 }
354 
355 void
356 fuse_vnode_refreshsize(struct vnode *vp, struct ucred *cred)
357 {
358 
359 	struct fuse_vnode_data *fvdat = VTOFUD(vp);
360 	struct vattr va;
361 
362 	if ((fvdat->flag & FN_SIZECHANGE) != 0 ||
363 	    (fuse_refresh_size == 0 && fvdat->filesize != 0))
364 		return;
365 
366 	VOP_GETATTR(vp, &va, cred);
367 	FS_DEBUG("refreshed file size: %jd\n", (intmax_t)VTOFUD(vp)->filesize);
368 }
369 
370 int
371 fuse_vnode_setsize(struct vnode *vp, struct ucred *cred, off_t newsize)
372 {
373 	struct fuse_vnode_data *fvdat = VTOFUD(vp);
374 	off_t oldsize;
375 	int err = 0;
376 
377 	FS_DEBUG("inode=%ju oldsize=%ju newsize=%ju\n",
378 	    (uintmax_t)VTOI(vp), (uintmax_t)fvdat->filesize,
379 	    (uintmax_t)newsize);
380 	ASSERT_VOP_ELOCKED(vp, "fuse_vnode_setsize");
381 
382 	oldsize = fvdat->filesize;
383 	fvdat->filesize = newsize;
384 	fvdat->flag |= FN_SIZECHANGE;
385 
386 	if (newsize < oldsize) {
387 		err = vtruncbuf(vp, cred, newsize, fuse_iosize(vp));
388 	}
389 	vnode_pager_setsize(vp, newsize);
390 	return err;
391 }
392