1 /* 2 * Copyright (c) 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * This code is derived from software contributed to Berkeley by 6 * Rick Macklem at The University of Guelph. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. All advertising materials mentioning features or use of this software 17 * must display the following acknowledgement: 18 * This product includes software developed by the University of 19 * California, Berkeley and its contributors. 20 * 4. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * @(#)nfs_node.c 8.6 (Berkeley) 5/22/95 37 * $FreeBSD: src/sys/nfs/nfs_node.c,v 1.36.2.3 2002/01/05 22:25:04 dillon Exp $ 38 * $DragonFly: src/sys/vfs/nfs/nfs_node.c,v 1.27 2007/08/08 00:12:51 swildner Exp $ 39 */ 40 41 42 #include <sys/param.h> 43 #include <sys/systm.h> 44 #include <sys/proc.h> 45 #include <sys/mount.h> 46 #include <sys/namei.h> 47 #include <sys/vnode.h> 48 #include <sys/malloc.h> 49 #include <sys/fnv_hash.h> 50 51 #include <vm/vm_zone.h> 52 53 #include "rpcv2.h" 54 #include "nfsproto.h" 55 #include "nfs.h" 56 #include "nfsmount.h" 57 #include "nfsnode.h" 58 59 static vm_zone_t nfsnode_zone; 60 static LIST_HEAD(nfsnodehashhead, nfsnode) *nfsnodehashtbl; 61 static u_long nfsnodehash; 62 63 #define TRUE 1 64 #define FALSE 0 65 66 #define NFSNOHASH(fhsum) (&nfsnodehashtbl[(fhsum) & nfsnodehash]) 67 68 /* 69 * Initialize hash links for nfsnodes 70 * and build nfsnode free list. 71 */ 72 void 73 nfs_nhinit(void) 74 { 75 nfsnode_zone = zinit("NFSNODE", sizeof(struct nfsnode), 0, 0, 1); 76 nfsnodehashtbl = hashinit(desiredvnodes, M_NFSHASH, &nfsnodehash); 77 } 78 79 /* 80 * Look up a vnode/nfsnode by file handle. 81 * Callers must check for mount points!! 82 * In all cases, a pointer to a 83 * nfsnode structure is returned. 84 */ 85 static int nfs_node_hash_lock; 86 87 int 88 nfs_nget(struct mount *mntp, nfsfh_t *fhp, int fhsize, struct nfsnode **npp) 89 { 90 struct nfsnode *np, *np2; 91 struct nfsnodehashhead *nhpp; 92 struct vnode *vp; 93 struct vnode *nvp; 94 int error; 95 int lkflags; 96 struct nfsmount *nmp; 97 98 /* 99 * Calculate nfs mount point and figure out whether the rslock should 100 * be interruptable or not. 101 */ 102 nmp = VFSTONFS(mntp); 103 if (nmp->nm_flag & NFSMNT_INT) 104 lkflags = LK_PCATCH; 105 else 106 lkflags = 0; 107 108 retry: 109 nhpp = NFSNOHASH(fnv_32_buf(fhp->fh_bytes, fhsize, FNV1_32_INIT)); 110 loop: 111 for (np = nhpp->lh_first; np; np = np->n_hash.le_next) { 112 if (mntp != NFSTOV(np)->v_mount || np->n_fhsize != fhsize || 113 bcmp((caddr_t)fhp, (caddr_t)np->n_fhp, fhsize)) { 114 continue; 115 } 116 vp = NFSTOV(np); 117 if (vget(vp, LK_EXCLUSIVE)) 118 goto loop; 119 for (np = nhpp->lh_first; np; np = np->n_hash.le_next) { 120 if (mntp == NFSTOV(np)->v_mount && 121 np->n_fhsize == fhsize && 122 bcmp((caddr_t)fhp, (caddr_t)np->n_fhp, fhsize) == 0 123 ) { 124 break; 125 } 126 } 127 if (np == NULL || NFSTOV(np) != vp) { 128 vput(vp); 129 goto loop; 130 } 131 *npp = np; 132 return(0); 133 } 134 /* 135 * Obtain a lock to prevent a race condition if the getnewvnode() 136 * or MALLOC() below happens to block. 137 */ 138 if (nfs_node_hash_lock) { 139 while (nfs_node_hash_lock) { 140 nfs_node_hash_lock = -1; 141 tsleep(&nfs_node_hash_lock, 0, "nfsngt", 0); 142 } 143 goto loop; 144 } 145 nfs_node_hash_lock = 1; 146 147 /* 148 * Allocate before getnewvnode since doing so afterward 149 * might cause a bogus v_data pointer to get dereferenced 150 * elsewhere if zalloc should block. 151 */ 152 np = zalloc(nfsnode_zone); 153 154 error = getnewvnode(VT_NFS, mntp, &nvp, 0, 0); 155 if (error) { 156 if (nfs_node_hash_lock < 0) 157 wakeup(&nfs_node_hash_lock); 158 nfs_node_hash_lock = 0; 159 *npp = 0; 160 zfree(nfsnode_zone, np); 161 return (error); 162 } 163 vp = nvp; 164 bzero((caddr_t)np, sizeof *np); 165 np->n_vnode = vp; 166 vp->v_data = np; 167 168 /* 169 * Insert the nfsnode in the hash queue for its new file handle 170 */ 171 for (np2 = nhpp->lh_first; np2 != 0; np2 = np2->n_hash.le_next) { 172 if (mntp != NFSTOV(np2)->v_mount || np2->n_fhsize != fhsize || 173 bcmp((caddr_t)fhp, (caddr_t)np2->n_fhp, fhsize)) 174 continue; 175 vx_put(vp); 176 if (nfs_node_hash_lock < 0) 177 wakeup(&nfs_node_hash_lock); 178 nfs_node_hash_lock = 0; 179 zfree(nfsnode_zone, np); 180 goto retry; 181 } 182 LIST_INSERT_HEAD(nhpp, np, n_hash); 183 if (fhsize > NFS_SMALLFH) { 184 MALLOC(np->n_fhp, nfsfh_t *, fhsize, M_NFSBIGFH, M_WAITOK); 185 } else 186 np->n_fhp = &np->n_fh; 187 bcopy((caddr_t)fhp, (caddr_t)np->n_fhp, fhsize); 188 np->n_fhsize = fhsize; 189 lockinit(&np->n_rslock, "nfrslk", 0, lkflags); 190 191 /* 192 * nvp is locked & refd so effectively so is np. 193 */ 194 *npp = np; 195 196 if (nfs_node_hash_lock < 0) 197 wakeup(&nfs_node_hash_lock); 198 nfs_node_hash_lock = 0; 199 200 return (0); 201 } 202 203 /* 204 * nfs_inactive(struct vnode *a_vp) 205 * 206 * NOTE: the passed vnode is locked but not referenced. On return the 207 * vnode must be unlocked and not referenced. 208 */ 209 int 210 nfs_inactive(struct vop_inactive_args *ap) 211 { 212 struct nfsnode *np; 213 struct sillyrename *sp; 214 215 np = VTONFS(ap->a_vp); 216 if (prtactive && ap->a_vp->v_sysref.refcnt > 1) 217 vprint("nfs_inactive: pushing active", ap->a_vp); 218 if (ap->a_vp->v_type != VDIR) { 219 sp = np->n_sillyrename; 220 np->n_sillyrename = NULL; 221 } else { 222 sp = NULL; 223 } 224 if (sp) { 225 /* 226 * We need a reference to keep the vnode from being 227 * recycled by getnewvnode while we do the I/O 228 * associated with discarding the buffers. The vnode 229 * is already locked. 230 */ 231 nfs_vinvalbuf(ap->a_vp, 0, 1); 232 233 /* 234 * Remove the silly file that was rename'd earlier 235 */ 236 nfs_removeit(sp); 237 crfree(sp->s_cred); 238 vrele(sp->s_dvp); 239 FREE((caddr_t)sp, M_NFSREQ); 240 } 241 242 np->n_flag &= ~(NWRITEERR | NACC | NUPD | NCHG | NLOCKED | NWANTED); 243 244 return (0); 245 } 246 247 /* 248 * Reclaim an nfsnode so that it can be used for other purposes. 249 * 250 * nfs_reclaim(struct vnode *a_vp) 251 */ 252 int 253 nfs_reclaim(struct vop_reclaim_args *ap) 254 { 255 struct vnode *vp = ap->a_vp; 256 struct nfsnode *np = VTONFS(vp); 257 struct nfsdmap *dp, *dp2; 258 259 if (prtactive && vp->v_sysref.refcnt > 1) 260 vprint("nfs_reclaim: pushing active", vp); 261 262 if (np->n_hash.le_prev != NULL) 263 LIST_REMOVE(np, n_hash); 264 265 /* 266 * Free up any directory cookie structures and 267 * large file handle structures that might be associated with 268 * this nfs node. 269 */ 270 if (vp->v_type == VDIR) { 271 dp = np->n_cookies.lh_first; 272 while (dp) { 273 dp2 = dp; 274 dp = dp->ndm_list.le_next; 275 FREE((caddr_t)dp2, M_NFSDIROFF); 276 } 277 } 278 if (np->n_fhsize > NFS_SMALLFH) { 279 FREE((caddr_t)np->n_fhp, M_NFSBIGFH); 280 } 281 if (np->n_rucred) { 282 crfree(np->n_rucred); 283 np->n_rucred = NULL; 284 } 285 if (np->n_wucred) { 286 crfree(np->n_wucred); 287 np->n_wucred = NULL; 288 } 289 290 vp->v_data = NULL; 291 zfree(nfsnode_zone, np); 292 return (0); 293 } 294 295