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 1.8 2003/10/10 22:01:13 dillon 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 /* 67 * Initialize hash links for nfsnodes 68 * and build nfsnode free list. 69 */ 70 void 71 nfs_nhinit() 72 { 73 nfsnode_zone = zinit("NFSNODE", sizeof(struct nfsnode), 0, 0, 1); 74 nfsnodehashtbl = hashinit(desiredvnodes, M_NFSHASH, &nfsnodehash); 75 } 76 77 /* 78 * Look up a vnode/nfsnode by file handle. 79 * Callers must check for mount points!! 80 * In all cases, a pointer to a 81 * nfsnode structure is returned. 82 */ 83 static int nfs_node_hash_lock; 84 85 int 86 nfs_nget(struct mount *mntp, nfsfh_t *fhp, int fhsize, struct nfsnode **npp) 87 { 88 struct thread *td = curthread; /* XXX */ 89 struct nfsnode *np, *np2; 90 struct nfsnodehashhead *nhpp; 91 struct vnode *vp; 92 struct vnode *nvp; 93 int error; 94 int rsflags; 95 struct nfsmount *nmp; 96 97 /* 98 * Calculate nfs mount point and figure out whether the rslock should 99 * be interruptable or not. 100 */ 101 nmp = VFSTONFS(mntp); 102 if (nmp->nm_flag & NFSMNT_INT) 103 rsflags = PCATCH; 104 else 105 rsflags = 0; 106 107 retry: 108 nhpp = NFSNOHASH(fnv_32_buf(fhp->fh_bytes, fhsize, FNV1_32_INIT)); 109 loop: 110 for (np = nhpp->lh_first; np != 0; np = np->n_hash.le_next) { 111 if (mntp != NFSTOV(np)->v_mount || np->n_fhsize != fhsize || 112 bcmp((caddr_t)fhp, (caddr_t)np->n_fhp, fhsize)) 113 continue; 114 vp = NFSTOV(np); 115 if (vget(vp, LK_EXCLUSIVE|LK_SLEEPFAIL, td)) 116 goto loop; 117 *npp = np; 118 return(0); 119 } 120 /* 121 * Obtain a lock to prevent a race condition if the getnewvnode() 122 * or MALLOC() below happens to block. 123 */ 124 if (nfs_node_hash_lock) { 125 while (nfs_node_hash_lock) { 126 nfs_node_hash_lock = -1; 127 tsleep(&nfs_node_hash_lock, 0, "nfsngt", 0); 128 } 129 goto loop; 130 } 131 nfs_node_hash_lock = 1; 132 133 /* 134 * Allocate before getnewvnode since doing so afterward 135 * might cause a bogus v_data pointer to get dereferenced 136 * elsewhere if zalloc should block. 137 */ 138 np = zalloc(nfsnode_zone); 139 140 error = getnewvnode(VT_NFS, mntp, nfsv2_vnodeop_p, &nvp); 141 if (error) { 142 if (nfs_node_hash_lock < 0) 143 wakeup(&nfs_node_hash_lock); 144 nfs_node_hash_lock = 0; 145 *npp = 0; 146 zfree(nfsnode_zone, np); 147 return (error); 148 } 149 vp = nvp; 150 bzero((caddr_t)np, sizeof *np); 151 vp->v_data = np; 152 np->n_vnode = vp; 153 /* 154 * Insert the nfsnode in the hash queue for its new file handle 155 */ 156 for (np2 = nhpp->lh_first; np2 != 0; np2 = np2->n_hash.le_next) { 157 if (mntp != NFSTOV(np2)->v_mount || np2->n_fhsize != fhsize || 158 bcmp((caddr_t)fhp, (caddr_t)np2->n_fhp, fhsize)) 159 continue; 160 vrele(vp); 161 if (nfs_node_hash_lock < 0) 162 wakeup(&nfs_node_hash_lock); 163 nfs_node_hash_lock = 0; 164 zfree(nfsnode_zone, np); 165 goto retry; 166 } 167 LIST_INSERT_HEAD(nhpp, np, n_hash); 168 if (fhsize > NFS_SMALLFH) { 169 MALLOC(np->n_fhp, nfsfh_t *, fhsize, M_NFSBIGFH, M_WAITOK); 170 } else 171 np->n_fhp = &np->n_fh; 172 bcopy((caddr_t)fhp, (caddr_t)np->n_fhp, fhsize); 173 np->n_fhsize = fhsize; 174 lockinit(&np->n_rslock, rsflags, "nfrslk", 0, LK_NOPAUSE); 175 lockinit(&np->n_lock, 0, "nfsnlk", 0, LK_NOPAUSE); 176 *npp = np; 177 178 if (nfs_node_hash_lock < 0) 179 wakeup(&nfs_node_hash_lock); 180 nfs_node_hash_lock = 0; 181 182 /* 183 * Lock the new nfsnode. 184 */ 185 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, td); 186 187 return (0); 188 } 189 190 int 191 nfs_inactive(ap) 192 struct vop_inactive_args /* { 193 struct vnode *a_vp; 194 struct thread *a_td; 195 } */ *ap; 196 { 197 struct nfsnode *np; 198 struct sillyrename *sp; 199 200 np = VTONFS(ap->a_vp); 201 if (prtactive && ap->a_vp->v_usecount != 0) 202 vprint("nfs_inactive: pushing active", ap->a_vp); 203 if (ap->a_vp->v_type != VDIR) { 204 sp = np->n_sillyrename; 205 np->n_sillyrename = (struct sillyrename *)0; 206 } else 207 sp = (struct sillyrename *)0; 208 if (sp) { 209 /* 210 * We need a reference to keep the vnode from being 211 * recycled by getnewvnode while we do the I/O 212 * associated with discarding the buffers unless we 213 * are being forcibly unmounted in which case we already 214 * have our own reference. 215 */ 216 if (ap->a_vp->v_usecount > 0) 217 (void) nfs_vinvalbuf(ap->a_vp, 0, ap->a_td, 1); 218 else if (vget(ap->a_vp, 0, ap->a_td)) 219 panic("nfs_inactive: lost vnode"); 220 else { 221 (void) nfs_vinvalbuf(ap->a_vp, 0, ap->a_td, 1); 222 vrele(ap->a_vp); 223 } 224 /* 225 * Remove the silly file that was rename'd earlier 226 */ 227 nfs_removeit(sp); 228 crfree(sp->s_cred); 229 vrele(sp->s_dvp); 230 FREE((caddr_t)sp, M_NFSREQ); 231 } 232 np->n_flag &= (NMODIFIED | NFLUSHINPROG | NFLUSHWANT | NQNFSEVICTED | 233 NQNFSNONCACHE | NQNFSWRITE); 234 VOP_UNLOCK(ap->a_vp, 0, ap->a_td); 235 return (0); 236 } 237 238 /* 239 * Reclaim an nfsnode so that it can be used for other purposes. 240 */ 241 int 242 nfs_reclaim(ap) 243 struct vop_reclaim_args /* { 244 struct vnode *a_vp; 245 } */ *ap; 246 { 247 struct vnode *vp = ap->a_vp; 248 struct nfsnode *np = VTONFS(vp); 249 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 250 struct nfsdmap *dp, *dp2; 251 252 if (prtactive && vp->v_usecount != 0) 253 vprint("nfs_reclaim: pushing active", vp); 254 255 if (np->n_hash.le_prev != NULL) 256 LIST_REMOVE(np, n_hash); 257 258 /* 259 * For nqnfs, take it off the timer queue as required. 260 */ 261 if ((nmp->nm_flag & NFSMNT_NQNFS) && np->n_timer.cqe_next != 0) { 262 CIRCLEQ_REMOVE(&nmp->nm_timerhead, np, n_timer); 263 } 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 cache_purge(vp); 291 zfree(nfsnode_zone, vp->v_data); 292 vp->v_data = (void *)0; 293 return (0); 294 } 295 296 #if 0 297 /* 298 * Lock an nfsnode 299 */ 300 int 301 nfs_lock(ap) 302 struct vop_lock_args /* { 303 struct vnode *a_vp; 304 } */ *ap; 305 { 306 struct vnode *vp = ap->a_vp; 307 308 /* 309 * Ugh, another place where interruptible mounts will get hung. 310 * If you make this sleep interruptible, then you have to fix all 311 * the VOP_LOCK() calls to expect interruptibility. 312 */ 313 while (vp->v_flag & VXLOCK) { 314 vp->v_flag |= VXWANT; 315 (void) tsleep((caddr_t)vp, 0, "nfslck", 0); 316 } 317 if (vp->v_tag == VT_NON) 318 return (ENOENT); 319 320 #if 0 321 /* 322 * Only lock regular files. If a server crashed while we were 323 * holding a directory lock, we could easily end up sleeping 324 * until the server rebooted while holding a lock on the root. 325 * Locks are only needed for protecting critical sections in 326 * VMIO at the moment. 327 * New vnodes will have type VNON but they should be locked 328 * since they may become VREG. This is checked in loadattrcache 329 * and unwanted locks are released there. 330 */ 331 if (vp->v_type == VREG || vp->v_type == VNON) { 332 while (np->n_flag & NLOCKED) { 333 np->n_flag |= NWANTED; 334 (void) tsleep((caddr_t) np, 0, "nfslck2", 0); 335 /* 336 * If the vnode has transmuted into a VDIR while we 337 * were asleep, then skip the lock. 338 */ 339 if (vp->v_type != VREG && vp->v_type != VNON) 340 return (0); 341 } 342 np->n_flag |= NLOCKED; 343 } 344 #endif 345 346 return (0); 347 } 348 349 /* 350 * Unlock an nfsnode 351 */ 352 int 353 nfs_unlock(ap) 354 struct vop_unlock_args /* { 355 struct vnode *a_vp; 356 } */ *ap; 357 { 358 #if 0 359 struct vnode* vp = ap->a_vp; 360 struct nfsnode* np = VTONFS(vp); 361 362 if (vp->v_type == VREG || vp->v_type == VNON) { 363 if (!(np->n_flag & NLOCKED)) 364 panic("nfs_unlock: nfsnode not locked"); 365 np->n_flag &= ~NLOCKED; 366 if (np->n_flag & NWANTED) { 367 np->n_flag &= ~NWANTED; 368 wakeup((caddr_t) np); 369 } 370 } 371 #endif 372 373 return (0); 374 } 375 376 /* 377 * Check for a locked nfsnode 378 */ 379 int 380 nfs_islocked(ap) 381 struct vop_islocked_args /* { 382 struct vnode *a_vp; 383 struct thread *a_td; 384 } */ *ap; 385 { 386 return VTONFS(ap->a_vp)->n_flag & NLOCKED ? 1 : 0; 387 } 388 #endif 389 390