xref: /openbsd-src/sys/nfs/nfs_node.c (revision ae3cb403620ab940fbaabb3055fac045a63d56b7)
1 /*	$OpenBSD: nfs_node.c,v 1.65 2016/09/27 01:37:38 dlg Exp $	*/
2 /*	$NetBSD: nfs_node.c,v 1.16 1996/02/18 11:53:42 fvdl Exp $	*/
3 
4 /*
5  * Copyright (c) 1989, 1993
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * This code is derived from software contributed to Berkeley by
9  * Rick Macklem at The University of Guelph.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  *
35  *	@(#)nfs_node.c	8.6 (Berkeley) 5/22/95
36  */
37 
38 
39 #include <sys/param.h>
40 #include <sys/systm.h>
41 #include <sys/timeout.h>
42 #include <sys/mount.h>
43 #include <sys/namei.h>
44 #include <sys/vnode.h>
45 #include <sys/lock.h>
46 #include <sys/kernel.h>
47 #include <sys/malloc.h>
48 #include <sys/pool.h>
49 #include <sys/rwlock.h>
50 #include <sys/queue.h>
51 
52 #include <nfs/rpcv2.h>
53 #include <nfs/nfsproto.h>
54 #include <nfs/nfsnode.h>
55 #include <nfs/nfsmount.h>
56 #include <nfs/nfs_var.h>
57 
58 struct pool nfs_node_pool;
59 extern int prtactive;
60 
61 struct rwlock nfs_hashlock = RWLOCK_INITIALIZER("nfshshlk");
62 
63 /* XXX */
64 extern struct vops nfs_vops;
65 
66 /* filehandle to node lookup. */
67 static __inline int
68 nfsnode_cmp(const struct nfsnode *a, const struct nfsnode *b)
69 {
70 	if (a->n_fhsize != b->n_fhsize)
71 		return (a->n_fhsize - b->n_fhsize);
72 	return (memcmp(a->n_fhp, b->n_fhp, a->n_fhsize));
73 }
74 
75 RBT_PROTOTYPE(nfs_nodetree, nfsnode, n_entry, nfsnode_cmp);
76 RBT_GENERATE(nfs_nodetree, nfsnode, n_entry, nfsnode_cmp);
77 
78 void
79 nfs_ninit(struct nfsmount *nmp)
80 {
81 	RBT_INIT(nfs_nodetree, &nmp->nm_ntree);
82 }
83 
84 /*
85  * Look up a vnode/nfsnode by file handle and store the pointer in *npp.
86  * Callers must check for mount points!!
87  * An error number is returned.
88  */
89 int
90 nfs_nget(struct mount *mnt, nfsfh_t *fh, int fhsize, struct nfsnode **npp)
91 {
92 	struct nfsmount		*nmp;
93 	struct nfsnode		*np, find, *np2;
94 	struct vnode		*vp, *nvp;
95 	struct proc		*p = curproc;		/* XXX */
96 	int			 error;
97 
98 	nmp = VFSTONFS(mnt);
99 
100 loop:
101 	rw_enter_write(&nfs_hashlock);
102 	find.n_fhp = fh;
103 	find.n_fhsize = fhsize;
104 	np = RBT_FIND(nfs_nodetree, &nmp->nm_ntree, &find);
105 	if (np != NULL) {
106 		rw_exit_write(&nfs_hashlock);
107 		vp = NFSTOV(np);
108 		error = vget(vp, LK_EXCLUSIVE, p);
109 		if (error)
110 			goto loop;
111 		*npp = np;
112 		return (0);
113 	}
114 
115 	/*
116 	 * getnewvnode() could recycle a vnode, potentially formerly
117 	 * owned by NFS. This will cause a VOP_RECLAIM() to happen,
118 	 * which will cause recursive locking, so we unlock before
119 	 * calling getnewvnode() lock again afterwards, but must check
120 	 * to see if this nfsnode has been added while we did not hold
121 	 * the lock.
122 	 */
123 	rw_exit_write(&nfs_hashlock);
124 	error = getnewvnode(VT_NFS, mnt, &nfs_vops, &nvp);
125 	/* note that we don't have this vnode set up completely yet */
126 	rw_enter_write(&nfs_hashlock);
127 	if (error) {
128 		*npp = NULL;
129 		rw_exit_write(&nfs_hashlock);
130 		return (error);
131 	}
132 	nvp->v_flag |= VLARVAL;
133 	np = RBT_FIND(nfs_nodetree, &nmp->nm_ntree, &find);
134 	if (np != NULL) {
135 		vgone(nvp);
136 		rw_exit_write(&nfs_hashlock);
137 		goto loop;
138 	}
139 
140 	vp = nvp;
141 	np = pool_get(&nfs_node_pool, PR_WAITOK | PR_ZERO);
142 	vp->v_data = np;
143 	/* we now have an nfsnode on this vnode */
144 	vp->v_flag &= ~VLARVAL;
145 	np->n_vnode = vp;
146 
147 	rw_init(&np->n_commitlock, "nfs_commitlk");
148 
149 	/*
150 	 * Are we getting the root? If so, make sure the vnode flags
151 	 * are correct
152 	 */
153 	if ((fhsize == nmp->nm_fhsize) && !bcmp(fh, nmp->nm_fh, fhsize)) {
154 		if (vp->v_type == VNON)
155 			vp->v_type = VDIR;
156 		vp->v_flag |= VROOT;
157 	}
158 
159 	np->n_fhp = &np->n_fh;
160 	bcopy(fh, np->n_fhp, fhsize);
161 	np->n_fhsize = fhsize;
162 	np2 = RBT_INSERT(nfs_nodetree, &nmp->nm_ntree, np);
163 	KASSERT(np2 == NULL);
164 	np->n_accstamp = -1;
165 	rw_exit(&nfs_hashlock);
166 	*npp = np;
167 
168 	return (0);
169 }
170 
171 int
172 nfs_inactive(void *v)
173 {
174 	struct vop_inactive_args	*ap = v;
175 	struct nfsnode			*np;
176 	struct sillyrename		*sp;
177 
178 #ifdef DIAGNOSTIC
179 	if (prtactive && ap->a_vp->v_usecount != 0)
180 		vprint("nfs_inactive: pushing active", ap->a_vp);
181 #endif
182 	if (ap->a_vp->v_flag & VLARVAL)
183 		/*
184 		 * vnode was incompletely set up, just return
185 		 * as we are throwing it away.
186 		 */
187 		return(0);
188 #ifdef DIAGNOSTIC
189 	if (ap->a_vp->v_data == NULL)
190 		panic("NULL v_data (no nfsnode set up?) in vnode %p",
191 		    ap->a_vp);
192 #endif
193 	np = VTONFS(ap->a_vp);
194 	if (ap->a_vp->v_type != VDIR) {
195 		sp = np->n_sillyrename;
196 		np->n_sillyrename = NULL;
197 	} else
198 		sp = NULL;
199 	if (sp) {
200 		/*
201 		 * Remove the silly file that was rename'd earlier
202 		 */
203 		nfs_vinvalbuf(ap->a_vp, 0, sp->s_cred, curproc);
204 		nfs_removeit(sp);
205 		crfree(sp->s_cred);
206 		vrele(sp->s_dvp);
207 		free(sp, M_NFSREQ, sizeof(*sp));
208 	}
209 	np->n_flag &= (NMODIFIED | NFLUSHINPROG | NFLUSHWANT);
210 
211 	VOP_UNLOCK(ap->a_vp, ap->a_p);
212 	return (0);
213 }
214 
215 /*
216  * Reclaim an nfsnode so that it can be used for other purposes.
217  */
218 int
219 nfs_reclaim(void *v)
220 {
221 	struct vop_reclaim_args	*ap = v;
222 	struct vnode		*vp = ap->a_vp;
223 	struct nfsmount		*nmp;
224 	struct nfsnode		*np = VTONFS(vp);
225 
226 #ifdef DIAGNOSTIC
227 	if (prtactive && vp->v_usecount != 0)
228 		vprint("nfs_reclaim: pushing active", vp);
229 #endif
230 	if (ap->a_vp->v_flag & VLARVAL)
231 		/*
232 		 * vnode was incompletely set up, just return
233 		 * as we are throwing it away.
234 		 */
235 		return(0);
236 #ifdef DIAGNOSTIC
237 	if (ap->a_vp->v_data == NULL)
238 		panic("NULL v_data (no nfsnode set up?) in vnode %p",
239 		    ap->a_vp);
240 #endif
241 	nmp = VFSTONFS(vp->v_mount);
242 	rw_enter_write(&nfs_hashlock);
243 	RBT_REMOVE(nfs_nodetree, &nmp->nm_ntree, np);
244 	rw_exit_write(&nfs_hashlock);
245 
246 	if (np->n_rcred)
247 		crfree(np->n_rcred);
248 	if (np->n_wcred)
249 		crfree(np->n_wcred);
250 
251 	cache_purge(vp);
252 	pool_put(&nfs_node_pool, vp->v_data);
253 	vp->v_data = NULL;
254 
255 	return (0);
256 }
257