xref: /openbsd/sys/nfs/nfs_node.c (revision 564dba15)
1 /*	$OpenBSD: nfs_node.c,v 1.76 2024/05/01 13:15:59 jsg 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/malloc.h>
47 #include <sys/pool.h>
48 #include <sys/rwlock.h>
49 
50 #include <nfs/nfsproto.h>
51 #include <nfs/nfsnode.h>
52 #include <nfs/nfsmount.h>
53 #include <nfs/nfs_var.h>
54 
55 struct pool nfs_node_pool;
56 extern int prtactive;
57 
58 /* XXX */
59 extern const struct vops nfs_vops;
60 
61 /* filehandle to node lookup. */
62 static __inline int
nfsnode_cmp(const struct nfsnode * a,const struct nfsnode * b)63 nfsnode_cmp(const struct nfsnode *a, const struct nfsnode *b)
64 {
65 	if (a->n_fhsize != b->n_fhsize)
66 		return (a->n_fhsize - b->n_fhsize);
67 	return (memcmp(a->n_fhp, b->n_fhp, a->n_fhsize));
68 }
69 
70 RBT_PROTOTYPE(nfs_nodetree, nfsnode, n_entry, nfsnode_cmp);
71 RBT_GENERATE(nfs_nodetree, nfsnode, n_entry, nfsnode_cmp);
72 
73 void
nfs_ninit(struct nfsmount * nmp)74 nfs_ninit(struct nfsmount *nmp)
75 {
76 	RBT_INIT(nfs_nodetree, &nmp->nm_ntree);
77 }
78 
79 /*
80  * Look up a vnode/nfsnode by file handle and store the pointer in *npp.
81  * Callers must check for mount points!!
82  * An error number is returned.
83  */
84 int
nfs_nget(struct mount * mnt,nfsfh_t * fh,int fhsize,struct nfsnode ** npp)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 	int			 error;
91 
92 	nmp = VFSTONFS(mnt);
93 
94 loop:
95 	find.n_fhp = fh;
96 	find.n_fhsize = fhsize;
97 	np = RBT_FIND(nfs_nodetree, &nmp->nm_ntree, &find);
98 	if (np != NULL) {
99 		vp = NFSTOV(np);
100 		error = vget(vp, LK_EXCLUSIVE);
101 		if (error)
102 			goto loop;
103 		*npp = np;
104 		return (0);
105 	}
106 
107 	/*
108 	 * getnewvnode() could recycle a vnode, potentially formerly
109 	 * owned by NFS. This will cause a VOP_RECLAIM() to happen,
110 	 * which will cause recursive locking, so we unlock before
111 	 * calling getnewvnode() lock again afterwards, but must check
112 	 * to see if this nfsnode has been added while we did not hold
113 	 * the lock.
114 	 */
115 	error = getnewvnode(VT_NFS, mnt, &nfs_vops, &nvp);
116 	/* note that we don't have this vnode set up completely yet */
117 	if (error) {
118 		*npp = NULL;
119 		return (error);
120 	}
121 	nvp->v_flag |= VLARVAL;
122 	np = pool_get(&nfs_node_pool, PR_WAITOK | PR_ZERO);
123 	/*
124 	 * getnewvnode() and pool_get() can sleep, check for race.
125 	 */
126 	if (RBT_FIND(nfs_nodetree, &nmp->nm_ntree, &find) != NULL) {
127 		pool_put(&nfs_node_pool, np);
128 		vgone(nvp);
129 		goto loop;
130 	}
131 
132 	vp = nvp;
133 #ifdef VFSLCKDEBUG
134 	vp->v_flag |= VLOCKSWORK;
135 #endif
136 	rrw_init_flags(&np->n_lock, "nfsnode", RWL_DUPOK | RWL_IS_VNODE);
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 	rw_init(&np->n_commitlock, "nfs_commitlk");
142 	np->n_fhp = &np->n_fh;
143 	bcopy(fh, np->n_fhp, fhsize);
144 	np->n_fhsize = fhsize;
145 	/* lock the nfsnode, then put it on the rbtree */
146 	VOP_LOCK(vp, LK_EXCLUSIVE);
147 	np2 = RBT_INSERT(nfs_nodetree, &nmp->nm_ntree, np);
148 	KASSERT(np2 == NULL);
149 	np->n_accstamp = -1;
150 	*npp = np;
151 
152 	return (0);
153 }
154 
155 int
nfs_inactive(void * v)156 nfs_inactive(void *v)
157 {
158 	struct vop_inactive_args	*ap = v;
159 	struct nfsnode			*np;
160 	struct sillyrename		*sp;
161 
162 #ifdef DIAGNOSTIC
163 	if (prtactive && ap->a_vp->v_usecount != 0)
164 		vprint("nfs_inactive: pushing active", ap->a_vp);
165 #endif
166 	if (ap->a_vp->v_flag & VLARVAL)
167 		/*
168 		 * vnode was incompletely set up, just return
169 		 * as we are throwing it away.
170 		 */
171 		return(0);
172 #ifdef DIAGNOSTIC
173 	if (ap->a_vp->v_data == NULL)
174 		panic("NULL v_data (no nfsnode set up?) in vnode %p",
175 		    ap->a_vp);
176 #endif
177 	np = VTONFS(ap->a_vp);
178 	if (ap->a_vp->v_type != VDIR) {
179 		sp = np->n_sillyrename;
180 		np->n_sillyrename = NULL;
181 	} else
182 		sp = NULL;
183 	if (sp != NULL)
184 		nfs_vinvalbuf(ap->a_vp, 0, sp->s_cred, curproc);
185 	np->n_flag &= (NMODIFIED | NFLUSHINPROG | NFLUSHWANT);
186 
187 	VOP_UNLOCK(ap->a_vp);
188 
189 	if (sp != NULL) {
190 		/*
191 		 * Remove the silly file that was rename'd earlier
192 		 */
193 		vn_lock(sp->s_dvp, LK_EXCLUSIVE | LK_RETRY);
194 		nfs_removeit(sp);
195 		crfree(sp->s_cred);
196 		vput(sp->s_dvp);
197 		free(sp, M_NFSREQ, sizeof(*sp));
198 	}
199 
200 	return (0);
201 }
202 
203 /*
204  * Reclaim an nfsnode so that it can be used for other purposes.
205  */
206 int
nfs_reclaim(void * v)207 nfs_reclaim(void *v)
208 {
209 	struct vop_reclaim_args	*ap = v;
210 	struct vnode		*vp = ap->a_vp;
211 	struct nfsmount		*nmp;
212 	struct nfsnode		*np = VTONFS(vp);
213 
214 #ifdef DIAGNOSTIC
215 	if (prtactive && vp->v_usecount != 0)
216 		vprint("nfs_reclaim: pushing active", vp);
217 #endif
218 	if (ap->a_vp->v_flag & VLARVAL)
219 		/*
220 		 * vnode was incompletely set up, just return
221 		 * as we are throwing it away.
222 		 */
223 		return(0);
224 #ifdef DIAGNOSTIC
225 	if (ap->a_vp->v_data == NULL)
226 		panic("NULL v_data (no nfsnode set up?) in vnode %p",
227 		    ap->a_vp);
228 #endif
229 	nmp = VFSTONFS(vp->v_mount);
230 	RBT_REMOVE(nfs_nodetree, &nmp->nm_ntree, np);
231 
232 	if (np->n_rcred)
233 		crfree(np->n_rcred);
234 	if (np->n_wcred)
235 		crfree(np->n_wcred);
236 
237 	cache_purge(vp);
238 	pool_put(&nfs_node_pool, vp->v_data);
239 	vp->v_data = NULL;
240 
241 	return (0);
242 }
243