1 /*-
2 * Copyright (c) 2019 Tomohiro Kusumi <tkusumi@netbsd.org>
3 * Copyright (c) 2019 The DragonFly Project
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 */
27
28 #include "fuse.h"
29
30 static MALLOC_DEFINE(M_FUSE_NODE, "fuse_node", "FUSE node");
31
32 static struct objcache *fuse_node_objcache = NULL;
33 static struct objcache_malloc_args fuse_node_args = {
34 sizeof(struct fuse_node), M_FUSE_NODE,
35 };
36
37 static int
fuse_node_cmp(struct fuse_node * p1,struct fuse_node * p2)38 fuse_node_cmp(struct fuse_node *p1, struct fuse_node *p2)
39 {
40 if (p1->ino < p2->ino)
41 return -1;
42 if (p1->ino > p2->ino)
43 return 1;
44 return 0;
45 }
46
47 RB_PROTOTYPE2(fuse_node_tree, fuse_node, entry, fuse_node_cmp, uint64_t);
48 RB_GENERATE2(fuse_node_tree, fuse_node, node_entry, fuse_node_cmp,
49 uint64_t, ino);
50
51 void
fuse_node_new(struct fuse_mount * fmp,uint64_t ino,enum vtype vtyp,struct fuse_node ** fnpp)52 fuse_node_new(struct fuse_mount *fmp, uint64_t ino, enum vtype vtyp,
53 struct fuse_node **fnpp)
54 {
55 struct fuse_node *fnp;
56
57 fnp = objcache_get(fuse_node_objcache, M_WAITOK);
58 bzero(fnp, sizeof(*fnp));
59
60 fnp->fmp = fmp;
61
62 mtx_init(&fnp->node_lock, "fuse_node_lock");
63
64 fnp->ino = ino;
65 fnp->type = vtyp;
66 fnp->size = 0;
67 fnp->nlookup = 0;
68 fnp->fh = 0;
69 fnp->closed = false;
70
71 if (RB_INSERT(fuse_node_tree, &fmp->node_head, fnp)) {
72 panic("fuse_node_new: cannot insert %p\n", fnp);
73 }
74
75 *fnpp = fnp;
76 }
77
78 void
fuse_node_free(struct fuse_mount * fmp,struct fuse_node * fnp)79 fuse_node_free(struct fuse_mount *fmp, struct fuse_node *fnp)
80 {
81 fuse_dbg("free ino=%ju\n", fnp->ino);
82
83 mtx_lock(&fmp->ino_lock);
84 RB_REMOVE(fuse_node_tree, &fmp->node_head, fnp);
85 mtx_unlock(&fmp->ino_lock);
86
87 objcache_put(fuse_node_objcache, fnp);
88 }
89
90 /*
91 * Allocate or find the fuse node for the specified inode number and assign
92 * its vnode.
93 */
94 int
fuse_alloc_node(struct fuse_mount * fmp,struct fuse_node * dfnp,uint64_t ino,enum vtype vtyp,struct vnode ** vpp)95 fuse_alloc_node(struct fuse_mount *fmp, struct fuse_node *dfnp,
96 uint64_t ino, enum vtype vtyp, struct vnode **vpp)
97 {
98 struct fuse_node *fnp;
99 int error;
100 int allocated = 0;
101
102 KKASSERT(dfnp->type == VDIR);
103 if (vtyp == VBLK || vtyp == VCHR || vtyp == VFIFO)
104 return EINVAL;
105
106 mtx_lock(&fmp->ino_lock);
107 fnp = RB_LOOKUP(fuse_node_tree, &fmp->node_head, ino);
108 if (fnp == NULL) {
109 fuse_node_new(fmp, ino, vtyp, &fnp);
110 allocated = 1;
111 }
112 mtx_unlock(&fmp->ino_lock);
113
114 error = fuse_node_vn(fnp, vpp);
115 if (error) {
116 if (allocated)
117 fuse_node_free(fmp, fnp);
118 }
119 return error;
120 }
121
122 /*
123 * Returns exclusively locked vp
124 */
125 int
fuse_node_vn(struct fuse_node * fnp,struct vnode ** vpp)126 fuse_node_vn(struct fuse_node *fnp, struct vnode **vpp)
127 {
128 struct mount *mp = fnp->fmp->mp;
129 struct vnode *vp;
130 struct vnode *newvp;
131 int error;
132
133 newvp = NULL;
134 retry:
135 error = 0;
136 if (fnp->vp == NULL && newvp == NULL) {
137 error = getnewvnode(VT_FUSE, mp, &newvp,
138 VLKTIMEOUT, LK_CANRECURSE);
139 if (error)
140 return error;
141 }
142
143 mtx_lock(&fnp->node_lock);
144
145 /*
146 * Check case where vp is already assigned
147 */
148 vp = fnp->vp;
149 if (vp) {
150 vhold(vp);
151 mtx_unlock(&fnp->node_lock);
152 error = vget(vp, LK_EXCLUSIVE | LK_RETRY);
153 vdrop(vp);
154
155 if (error)
156 goto retry;
157 if (fnp->vp != vp) {
158 vput(vp);
159 goto retry;
160 }
161
162 *vpp = vp;
163
164 if (newvp) {
165 newvp->v_type = VBAD;
166 vx_put(newvp);
167 }
168
169 return 0;
170 }
171
172 /*
173 * Assign new vp, release the node lock
174 */
175 if (newvp == NULL) {
176 mtx_unlock(&fnp->node_lock);
177 goto retry;
178 }
179
180 fnp->vp = newvp;
181 mtx_unlock(&fnp->node_lock);
182 vp = newvp;
183
184 /*
185 * Finish setting up vp (vp is held exclusively + vx)
186 */
187 vp->v_type = fnp->type;
188 vp->v_data = fnp;
189
190 switch (vp->v_type) {
191 case VREG:
192 vinitvmio(vp, fnp->size, FUSE_BLKSIZE, -1);
193 break;
194 case VDIR:
195 break;
196 case VBLK:
197 case VCHR:
198 KKASSERT(0);
199 vp->v_ops = &mp->mnt_vn_spec_ops;
200 addaliasu(vp, umajor(0), uminor(0)); /* XXX CUSE */
201 break;
202 case VLNK:
203 break;
204 case VSOCK:
205 break;
206 case VFIFO:
207 KKASSERT(0);
208 case VDATABASE:
209 break;
210 default:
211 KKASSERT(0);
212 }
213
214 vx_downgrade(vp); /* VX to normal, is still exclusive */
215
216 *vpp = vp;
217
218 return error;
219 }
220
221 int
fuse_node_truncate(struct fuse_node * fnp,size_t oldsize,size_t newsize)222 fuse_node_truncate(struct fuse_node *fnp, size_t oldsize, size_t newsize)
223 {
224 struct vnode *vp = fnp->vp;
225 int error;
226
227 fuse_dbg("ino=%ju update size %ju -> %ju\n",
228 fnp->ino, oldsize, newsize);
229
230 fnp->attr.va_size = fnp->size = newsize;
231
232 if (newsize < oldsize)
233 error = nvtruncbuf(vp, newsize, FUSE_BLKSIZE, -1, 0);
234 else
235 error = nvextendbuf(vp, oldsize, newsize, FUSE_BLKSIZE,
236 FUSE_BLKSIZE, -1, -1, 0);
237 return error;
238 }
239
240 void
fuse_node_init(void)241 fuse_node_init(void)
242 {
243 fuse_node_objcache = objcache_create("fuse_node", 0, 0,
244 NULL, NULL, NULL,
245 objcache_malloc_alloc_zero, objcache_malloc_free, &fuse_node_args);
246 }
247
248 void
fuse_node_cleanup(void)249 fuse_node_cleanup(void)
250 {
251 objcache_destroy(fuse_node_objcache);
252 }
253