xref: /openbsd-src/sys/nfs/nfs_node.c (revision 91f110e064cd7c194e59e019b83bb7496c1c84d4)
1 /*	$OpenBSD: nfs_node.c,v 1.55 2010/12/21 20:14:43 thib 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/proc.h>
42 #include <sys/mount.h>
43 #include <sys/namei.h>
44 #include <sys/vnode.h>
45 #include <sys/kernel.h>
46 #include <sys/malloc.h>
47 #include <sys/pool.h>
48 #include <sys/rwlock.h>
49 #include <sys/queue.h>
50 
51 #include <nfs/rpcv2.h>
52 #include <nfs/nfsproto.h>
53 #include <nfs/nfs.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 RB_PROTOTYPE(nfs_nodetree, nfsnode, n_entry, nfsnode_cmp);
76 RB_GENERATE(nfs_nodetree, nfsnode, n_entry, nfsnode_cmp);
77 
78 /*
79  * Look up a vnode/nfsnode by file handle.
80  * Callers must check for mount points!!
81  * In all cases, a pointer to a
82  * nfsnode structure is returned.
83  */
84 int
85 nfs_nget(struct mount *mnt, nfsfh_t *fh, int fhsize, struct nfsnode **npp)
86 {
87 	struct nfsmount		*nmp;
88 	struct nfsnode		*np, find, *np2;
89 	struct vnode		*vp, *nvp;
90 	struct proc		*p = curproc;		/* XXX */
91 	int			 error;
92 
93 	nmp = VFSTONFS(mnt);
94 
95 loop:
96 	rw_enter_write(&nfs_hashlock);
97 	find.n_fhp = fh;
98 	find.n_fhsize = fhsize;
99 	np = RB_FIND(nfs_nodetree, &nmp->nm_ntree, &find);
100 	if (np != NULL) {
101 		rw_exit_write(&nfs_hashlock);
102 		vp = NFSTOV(np);
103 		error = vget(vp, LK_EXCLUSIVE, p);
104 		if (error)
105 			goto loop;
106 		*npp = np;
107 		return (0);
108 	}
109 
110 	/*
111 	 * getnewvnode() could recycle a vnode, potentially formerly
112 	 * owned by NFS. This will cause a VOP_RECLAIM() to happen,
113 	 * which will cause recursive locking, so we unlock before
114 	 * calling getnewvnode() lock again afterwards, but must check
115 	 * to see if this nfsnode has been added while we did not hold
116 	 * the lock.
117 	 */
118 	rw_exit_write(&nfs_hashlock);
119 	error = getnewvnode(VT_NFS, mnt, &nfs_vops, &nvp);
120 	/* note that we don't have this vnode set up completely yet */
121 	rw_enter_write(&nfs_hashlock);
122 	if (error) {
123 		*npp = NULL;
124 		rw_exit_write(&nfs_hashlock);
125 		return (error);
126 	}
127 	nvp->v_flag |= VLARVAL;
128 	np = RB_FIND(nfs_nodetree, &nmp->nm_ntree, &find);
129 	if (np != NULL) {
130 		vgone(nvp);
131 		rw_exit_write(&nfs_hashlock);
132 		goto loop;
133 	}
134 
135 	vp = nvp;
136 	np = pool_get(&nfs_node_pool, PR_WAITOK | PR_ZERO);
137 	vp->v_data = np;
138 	/* we now have an nfsnode on this vnode */
139 	vp->v_flag &= ~VLARVAL;
140 	np->n_vnode = vp;
141 
142 	rw_init(&np->n_commitlock, "nfs_commitlk");
143 
144 	/*
145 	 * Are we getting the root? If so, make sure the vnode flags
146 	 * are correct
147 	 */
148 	if ((fhsize == nmp->nm_fhsize) && !bcmp(fh, nmp->nm_fh, fhsize)) {
149 		if (vp->v_type == VNON)
150 			vp->v_type = VDIR;
151 		vp->v_flag |= VROOT;
152 	}
153 
154 	np->n_fhp = &np->n_fh;
155 	bcopy(fh, np->n_fhp, fhsize);
156 	np->n_fhsize = fhsize;
157 	np2 = RB_INSERT(nfs_nodetree, &nmp->nm_ntree, np);
158 	KASSERT(np2 == NULL);
159 	np->n_accstamp = -1;
160 	rw_exit(&nfs_hashlock);
161 	*npp = np;
162 
163 	return (0);
164 }
165 
166 int
167 nfs_inactive(void *v)
168 {
169 	struct vop_inactive_args	*ap = v;
170 	struct nfsnode			*np;
171 	struct sillyrename		*sp;
172 
173 #ifdef DIAGNOSTIC
174 	if (prtactive && ap->a_vp->v_usecount != 0)
175 		vprint("nfs_inactive: pushing active", ap->a_vp);
176 #endif
177 	if (ap->a_vp->v_flag & VLARVAL)
178 		/*
179 		 * vnode was incompletely set up, just return
180 		 * as we are throwing it away.
181 		 */
182 		return(0);
183 #ifdef DIAGNOSTIC
184 	if (ap->a_vp->v_data == NULL)
185 		panic("NULL v_data (no nfsnode set up?) in vnode %p",
186 		    ap->a_vp);
187 #endif
188 	np = VTONFS(ap->a_vp);
189 	if (ap->a_vp->v_type != VDIR) {
190 		sp = np->n_sillyrename;
191 		np->n_sillyrename = NULL;
192 	} else
193 		sp = NULL;
194 	if (sp) {
195 		/*
196 		 * Remove the silly file that was rename'd earlier
197 		 */
198 		nfs_vinvalbuf(ap->a_vp, 0, sp->s_cred, curproc);
199 		nfs_removeit(sp);
200 		crfree(sp->s_cred);
201 		vrele(sp->s_dvp);
202 		free(sp, M_NFSREQ);
203 	}
204 	np->n_flag &= (NMODIFIED | NFLUSHINPROG | NFLUSHWANT);
205 
206 	VOP_UNLOCK(ap->a_vp, 0, ap->a_p);
207 	return (0);
208 }
209 
210 /*
211  * Reclaim an nfsnode so that it can be used for other purposes.
212  */
213 int
214 nfs_reclaim(void *v)
215 {
216 	struct vop_reclaim_args	*ap = v;
217 	struct vnode		*vp = ap->a_vp;
218 	struct nfsmount		*nmp;
219 	struct nfsnode		*np = VTONFS(vp);
220 
221 #ifdef DIAGNOSTIC
222 	if (prtactive && vp->v_usecount != 0)
223 		vprint("nfs_reclaim: pushing active", vp);
224 #endif
225 	if (ap->a_vp->v_flag & VLARVAL)
226 		/*
227 		 * vnode was incompletely set up, just return
228 		 * as we are throwing it away.
229 		 */
230 		return(0);
231 #ifdef DIAGNOSTIC
232 	if (ap->a_vp->v_data == NULL)
233 		panic("NULL v_data (no nfsnode set up?) in vnode %p",
234 		    ap->a_vp);
235 #endif
236 	nmp = VFSTONFS(vp->v_mount);
237 	rw_enter_write(&nfs_hashlock);
238 	RB_REMOVE(nfs_nodetree, &nmp->nm_ntree, np);
239 	rw_exit_write(&nfs_hashlock);
240 
241 	if (np->n_rcred)
242 		crfree(np->n_rcred);
243 	if (np->n_wcred)
244 		crfree(np->n_wcred);
245 
246 	cache_purge(vp);
247 	pool_put(&nfs_node_pool, vp->v_data);
248 	vp->v_data = NULL;
249 
250 	return (0);
251 }
252