xref: /openbsd/sys/nfs/nfs_node.c (revision 5af055cd)
1 /*	$OpenBSD: nfs_node.c,v 1.64 2016/03/19 12:04:16 natano 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 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 and store the pointer in *npp.
80  * Callers must check for mount points!!
81  * An error number is returned.
82  */
83 int
84 nfs_nget(struct mount *mnt, nfsfh_t *fh, int fhsize, struct nfsnode **npp)
85 {
86 	struct nfsmount		*nmp;
87 	struct nfsnode		*np, find, *np2;
88 	struct vnode		*vp, *nvp;
89 	struct proc		*p = curproc;		/* XXX */
90 	int			 error;
91 
92 	nmp = VFSTONFS(mnt);
93 
94 loop:
95 	rw_enter_write(&nfs_hashlock);
96 	find.n_fhp = fh;
97 	find.n_fhsize = fhsize;
98 	np = RB_FIND(nfs_nodetree, &nmp->nm_ntree, &find);
99 	if (np != NULL) {
100 		rw_exit_write(&nfs_hashlock);
101 		vp = NFSTOV(np);
102 		error = vget(vp, LK_EXCLUSIVE, p);
103 		if (error)
104 			goto loop;
105 		*npp = np;
106 		return (0);
107 	}
108 
109 	/*
110 	 * getnewvnode() could recycle a vnode, potentially formerly
111 	 * owned by NFS. This will cause a VOP_RECLAIM() to happen,
112 	 * which will cause recursive locking, so we unlock before
113 	 * calling getnewvnode() lock again afterwards, but must check
114 	 * to see if this nfsnode has been added while we did not hold
115 	 * the lock.
116 	 */
117 	rw_exit_write(&nfs_hashlock);
118 	error = getnewvnode(VT_NFS, mnt, &nfs_vops, &nvp);
119 	/* note that we don't have this vnode set up completely yet */
120 	rw_enter_write(&nfs_hashlock);
121 	if (error) {
122 		*npp = NULL;
123 		rw_exit_write(&nfs_hashlock);
124 		return (error);
125 	}
126 	nvp->v_flag |= VLARVAL;
127 	np = RB_FIND(nfs_nodetree, &nmp->nm_ntree, &find);
128 	if (np != NULL) {
129 		vgone(nvp);
130 		rw_exit_write(&nfs_hashlock);
131 		goto loop;
132 	}
133 
134 	vp = nvp;
135 	np = pool_get(&nfs_node_pool, PR_WAITOK | PR_ZERO);
136 	vp->v_data = np;
137 	/* we now have an nfsnode on this vnode */
138 	vp->v_flag &= ~VLARVAL;
139 	np->n_vnode = vp;
140 
141 	rw_init(&np->n_commitlock, "nfs_commitlk");
142 
143 	/*
144 	 * Are we getting the root? If so, make sure the vnode flags
145 	 * are correct
146 	 */
147 	if ((fhsize == nmp->nm_fhsize) && !bcmp(fh, nmp->nm_fh, fhsize)) {
148 		if (vp->v_type == VNON)
149 			vp->v_type = VDIR;
150 		vp->v_flag |= VROOT;
151 	}
152 
153 	np->n_fhp = &np->n_fh;
154 	bcopy(fh, np->n_fhp, fhsize);
155 	np->n_fhsize = fhsize;
156 	np2 = RB_INSERT(nfs_nodetree, &nmp->nm_ntree, np);
157 	KASSERT(np2 == NULL);
158 	np->n_accstamp = -1;
159 	rw_exit(&nfs_hashlock);
160 	*npp = np;
161 
162 	return (0);
163 }
164 
165 int
166 nfs_inactive(void *v)
167 {
168 	struct vop_inactive_args	*ap = v;
169 	struct nfsnode			*np;
170 	struct sillyrename		*sp;
171 
172 #ifdef DIAGNOSTIC
173 	if (prtactive && ap->a_vp->v_usecount != 0)
174 		vprint("nfs_inactive: pushing active", ap->a_vp);
175 #endif
176 	if (ap->a_vp->v_flag & VLARVAL)
177 		/*
178 		 * vnode was incompletely set up, just return
179 		 * as we are throwing it away.
180 		 */
181 		return(0);
182 #ifdef DIAGNOSTIC
183 	if (ap->a_vp->v_data == NULL)
184 		panic("NULL v_data (no nfsnode set up?) in vnode %p",
185 		    ap->a_vp);
186 #endif
187 	np = VTONFS(ap->a_vp);
188 	if (ap->a_vp->v_type != VDIR) {
189 		sp = np->n_sillyrename;
190 		np->n_sillyrename = NULL;
191 	} else
192 		sp = NULL;
193 	if (sp) {
194 		/*
195 		 * Remove the silly file that was rename'd earlier
196 		 */
197 		nfs_vinvalbuf(ap->a_vp, 0, sp->s_cred, curproc);
198 		nfs_removeit(sp);
199 		crfree(sp->s_cred);
200 		vrele(sp->s_dvp);
201 		free(sp, M_NFSREQ, sizeof(*sp));
202 	}
203 	np->n_flag &= (NMODIFIED | NFLUSHINPROG | NFLUSHWANT);
204 
205 	VOP_UNLOCK(ap->a_vp, ap->a_p);
206 	return (0);
207 }
208 
209 /*
210  * Reclaim an nfsnode so that it can be used for other purposes.
211  */
212 int
213 nfs_reclaim(void *v)
214 {
215 	struct vop_reclaim_args	*ap = v;
216 	struct vnode		*vp = ap->a_vp;
217 	struct nfsmount		*nmp;
218 	struct nfsnode		*np = VTONFS(vp);
219 
220 #ifdef DIAGNOSTIC
221 	if (prtactive && vp->v_usecount != 0)
222 		vprint("nfs_reclaim: pushing active", vp);
223 #endif
224 	if (ap->a_vp->v_flag & VLARVAL)
225 		/*
226 		 * vnode was incompletely set up, just return
227 		 * as we are throwing it away.
228 		 */
229 		return(0);
230 #ifdef DIAGNOSTIC
231 	if (ap->a_vp->v_data == NULL)
232 		panic("NULL v_data (no nfsnode set up?) in vnode %p",
233 		    ap->a_vp);
234 #endif
235 	nmp = VFSTONFS(vp->v_mount);
236 	rw_enter_write(&nfs_hashlock);
237 	RB_REMOVE(nfs_nodetree, &nmp->nm_ntree, np);
238 	rw_exit_write(&nfs_hashlock);
239 
240 	if (np->n_rcred)
241 		crfree(np->n_rcred);
242 	if (np->n_wcred)
243 		crfree(np->n_wcred);
244 
245 	cache_purge(vp);
246 	pool_put(&nfs_node_pool, vp->v_data);
247 	vp->v_data = NULL;
248 
249 	return (0);
250 }
251