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 static lwkt_token nfsnhash_token = LWKT_TOKEN_MP_INITIALIZER(nfsnhash_token); 63 static struct lock nfsnhash_lock; 64 65 #define TRUE 1 66 #define FALSE 0 67 68 #define NFSNOHASH(fhsum) (&nfsnodehashtbl[(fhsum) & nfsnodehash]) 69 70 /* 71 * Initialize hash links for nfsnodes 72 * and build nfsnode free list. 73 */ 74 void 75 nfs_nhinit(void) 76 { 77 nfsnode_zone = zinit("NFSNODE", sizeof(struct nfsnode), 0, 0, 1); 78 nfsnodehashtbl = hashinit(desiredvnodes, M_NFSHASH, &nfsnodehash); 79 lockinit(&nfsnhash_lock, "nfsnht", 0, 0); 80 } 81 82 /* 83 * Look up a vnode/nfsnode by file handle. 84 * Callers must check for mount points!! 85 * In all cases, a pointer to a 86 * nfsnode structure is returned. 87 */ 88 89 int 90 nfs_nget(struct mount *mntp, nfsfh_t *fhp, int fhsize, struct nfsnode **npp) 91 { 92 struct nfsnode *np, *np2; 93 struct nfsnodehashhead *nhpp; 94 struct vnode *vp; 95 struct vnode *nvp; 96 int error; 97 int lkflags; 98 struct nfsmount *nmp; 99 100 /* 101 * Calculate nfs mount point and figure out whether the rslock should 102 * be interruptable or not. 103 */ 104 nmp = VFSTONFS(mntp); 105 if (nmp->nm_flag & NFSMNT_INT) 106 lkflags = LK_PCATCH; 107 else 108 lkflags = 0; 109 110 lwkt_gettoken(&nfsnhash_token); 111 112 retry: 113 nhpp = NFSNOHASH(fnv_32_buf(fhp->fh_bytes, fhsize, FNV1_32_INIT)); 114 loop: 115 for (np = nhpp->lh_first; np; np = np->n_hash.le_next) { 116 if (mntp != NFSTOV(np)->v_mount || np->n_fhsize != fhsize || 117 bcmp((caddr_t)fhp, (caddr_t)np->n_fhp, fhsize)) { 118 continue; 119 } 120 vp = NFSTOV(np); 121 if (vget(vp, LK_EXCLUSIVE)) 122 goto loop; 123 for (np = nhpp->lh_first; np; np = np->n_hash.le_next) { 124 if (mntp == NFSTOV(np)->v_mount && 125 np->n_fhsize == fhsize && 126 bcmp((caddr_t)fhp, (caddr_t)np->n_fhp, fhsize) == 0 127 ) { 128 break; 129 } 130 } 131 if (np == NULL || NFSTOV(np) != vp) { 132 vput(vp); 133 goto loop; 134 } 135 *npp = np; 136 lwkt_reltoken(&nfsnhash_token); 137 return(0); 138 } 139 140 /* 141 * Obtain a lock to prevent a race condition if the getnewvnode() 142 * or MALLOC() below happens to block. 143 */ 144 if (lockmgr(&nfsnhash_lock, LK_EXCLUSIVE | LK_SLEEPFAIL)) 145 goto loop; 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 lockmgr(&nfsnhash_lock, LK_RELEASE); 157 *npp = 0; 158 zfree(nfsnode_zone, np); 159 lwkt_reltoken(&nfsnhash_token); 160 return (error); 161 } 162 vp = nvp; 163 bzero((caddr_t)np, sizeof *np); 164 np->n_vnode = vp; 165 vp->v_data = np; 166 167 /* 168 * Insert the nfsnode in the hash queue for its new file handle 169 */ 170 for (np2 = nhpp->lh_first; np2 != 0; np2 = np2->n_hash.le_next) { 171 if (mntp != NFSTOV(np2)->v_mount || np2->n_fhsize != fhsize || 172 bcmp((caddr_t)fhp, (caddr_t)np2->n_fhp, fhsize)) 173 continue; 174 vx_put(vp); 175 lockmgr(&nfsnhash_lock, LK_RELEASE); 176 zfree(nfsnode_zone, np); 177 goto retry; 178 } 179 LIST_INSERT_HEAD(nhpp, np, n_hash); 180 if (fhsize > NFS_SMALLFH) { 181 MALLOC(np->n_fhp, nfsfh_t *, fhsize, M_NFSBIGFH, M_WAITOK); 182 } else { 183 np->n_fhp = &np->n_fh; 184 } 185 bcopy((caddr_t)fhp, (caddr_t)np->n_fhp, fhsize); 186 np->n_fhsize = fhsize; 187 lockinit(&np->n_rslock, "nfrslk", 0, lkflags); 188 189 /* 190 * nvp is locked & refd so effectively so is np. 191 */ 192 *npp = np; 193 lockmgr(&nfsnhash_lock, LK_RELEASE); 194 lwkt_reltoken(&nfsnhash_token); 195 196 return (0); 197 } 198 199 /* 200 * Nonblocking version of nfs_nget() 201 */ 202 int 203 nfs_nget_nonblock(struct mount *mntp, nfsfh_t *fhp, int fhsize, 204 struct nfsnode **npp) 205 { 206 struct nfsnode *np, *np2; 207 struct nfsnodehashhead *nhpp; 208 struct vnode *vp; 209 struct vnode *nvp; 210 int error; 211 int lkflags; 212 struct nfsmount *nmp; 213 214 /* 215 * Calculate nfs mount point and figure out whether the rslock should 216 * be interruptable or not. 217 */ 218 nmp = VFSTONFS(mntp); 219 if (nmp->nm_flag & NFSMNT_INT) 220 lkflags = LK_PCATCH; 221 else 222 lkflags = 0; 223 vp = NULL; 224 *npp = NULL; 225 226 lwkt_gettoken(&nfsnhash_token); 227 228 retry: 229 nhpp = NFSNOHASH(fnv_32_buf(fhp->fh_bytes, fhsize, FNV1_32_INIT)); 230 loop: 231 for (np = nhpp->lh_first; np; np = np->n_hash.le_next) { 232 if (mntp != NFSTOV(np)->v_mount || np->n_fhsize != fhsize || 233 bcmp((caddr_t)fhp, (caddr_t)np->n_fhp, fhsize)) { 234 continue; 235 } 236 if (vp == NULL) { 237 vp = NFSTOV(np); 238 if (vget(vp, LK_EXCLUSIVE | LK_NOWAIT)) { 239 error = EWOULDBLOCK; 240 goto fail; 241 } 242 goto loop; 243 } 244 if (NFSTOV(np) != vp) { 245 vput(vp); 246 vp = NULL; 247 goto loop; 248 } 249 *npp = np; 250 lwkt_reltoken(&nfsnhash_token); 251 return(0); 252 } 253 254 /* 255 * Not found. If we raced and had acquired a vp we have to release 256 * it here. 257 */ 258 if (vp) { 259 vput(vp); 260 vp = NULL; 261 } 262 263 /* 264 * Obtain a lock to prevent a race condition if the getnewvnode() 265 * or MALLOC() below happens to block. 266 */ 267 if (lockmgr(&nfsnhash_lock, LK_EXCLUSIVE | LK_SLEEPFAIL)) 268 goto loop; 269 270 /* 271 * Entry not found, allocate a new entry. 272 * 273 * Allocate before getnewvnode since doing so afterward 274 * might cause a bogus v_data pointer to get dereferenced 275 * elsewhere if zalloc should block. 276 */ 277 np = zalloc(nfsnode_zone); 278 279 error = getnewvnode(VT_NFS, mntp, &nvp, 0, 0); 280 if (error) { 281 lockmgr(&nfsnhash_lock, LK_RELEASE); 282 zfree(nfsnode_zone, np); 283 lwkt_reltoken(&nfsnhash_token); 284 return (error); 285 } 286 vp = nvp; 287 bzero(np, sizeof (*np)); 288 np->n_vnode = vp; 289 vp->v_data = np; 290 291 /* 292 * Insert the nfsnode in the hash queue for its new file handle. 293 * If someone raced us we free np and vp and try again. 294 */ 295 for (np2 = nhpp->lh_first; np2 != 0; np2 = np2->n_hash.le_next) { 296 if (mntp != NFSTOV(np2)->v_mount || np2->n_fhsize != fhsize || 297 bcmp((caddr_t)fhp, (caddr_t)np2->n_fhp, fhsize)) { 298 continue; 299 } 300 vx_put(vp); 301 lockmgr(&nfsnhash_lock, LK_RELEASE); 302 zfree(nfsnode_zone, np); 303 goto retry; 304 } 305 LIST_INSERT_HEAD(nhpp, np, n_hash); 306 if (fhsize > NFS_SMALLFH) { 307 MALLOC(np->n_fhp, nfsfh_t *, fhsize, M_NFSBIGFH, M_WAITOK); 308 } else { 309 np->n_fhp = &np->n_fh; 310 } 311 bcopy((caddr_t)fhp, (caddr_t)np->n_fhp, fhsize); 312 np->n_fhsize = fhsize; 313 lockinit(&np->n_rslock, "nfrslk", 0, lkflags); 314 315 /* 316 * nvp is locked & refd so effectively so is np. 317 */ 318 *npp = np; 319 error = 0; 320 lockmgr(&nfsnhash_lock, LK_RELEASE); 321 fail: 322 lwkt_reltoken(&nfsnhash_token); 323 return (error); 324 } 325 326 /* 327 * nfs_inactive(struct vnode *a_vp) 328 * 329 * NOTE: the passed vnode is locked but not referenced. On return the 330 * vnode must be unlocked and not referenced. 331 */ 332 int 333 nfs_inactive(struct vop_inactive_args *ap) 334 { 335 struct nfsmount *nmp = VFSTONFS(ap->a_vp->v_mount); 336 struct nfsnode *np; 337 struct sillyrename *sp; 338 339 lwkt_gettoken(&nmp->nm_token); 340 341 np = VTONFS(ap->a_vp); 342 if (prtactive && ap->a_vp->v_sysref.refcnt > 1) 343 vprint("nfs_inactive: pushing active", ap->a_vp); 344 if (ap->a_vp->v_type != VDIR) { 345 sp = np->n_sillyrename; 346 np->n_sillyrename = NULL; 347 } else { 348 sp = NULL; 349 } 350 if (sp) { 351 /* 352 * We need a reference to keep the vnode from being 353 * recycled by getnewvnode while we do the I/O 354 * associated with discarding the buffers. The vnode 355 * is already locked. 356 */ 357 nfs_vinvalbuf(ap->a_vp, 0, 1); 358 359 /* 360 * Remove the silly file that was rename'd earlier 361 */ 362 nfs_removeit(sp); 363 crfree(sp->s_cred); 364 vrele(sp->s_dvp); 365 FREE((caddr_t)sp, M_NFSREQ); 366 } 367 368 np->n_flag &= ~(NWRITEERR | NACC | NUPD | NCHG | NLOCKED | NWANTED); 369 lwkt_reltoken(&nmp->nm_token); 370 371 return (0); 372 } 373 374 /* 375 * Reclaim an nfsnode so that it can be used for other purposes. 376 * 377 * nfs_reclaim(struct vnode *a_vp) 378 */ 379 int 380 nfs_reclaim(struct vop_reclaim_args *ap) 381 { 382 struct vnode *vp = ap->a_vp; 383 struct nfsnode *np = VTONFS(vp); 384 struct nfsdmap *dp, *dp2; 385 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 386 387 if (prtactive && vp->v_sysref.refcnt > 1) 388 vprint("nfs_reclaim: pushing active", vp); 389 390 391 /* 392 * Remove from hash table 393 */ 394 lwkt_gettoken(&nfsnhash_token); 395 if (np->n_hash.le_prev != NULL) 396 LIST_REMOVE(np, n_hash); 397 lwkt_reltoken(&nfsnhash_token); 398 399 /* 400 * Free up any directory cookie structures and 401 * large file handle structures that might be associated with 402 * this nfs node. 403 */ 404 lwkt_gettoken(&nmp->nm_token); 405 if (vp->v_type == VDIR) { 406 dp = np->n_cookies.lh_first; 407 while (dp) { 408 dp2 = dp; 409 dp = dp->ndm_list.le_next; 410 FREE((caddr_t)dp2, M_NFSDIROFF); 411 } 412 } 413 if (np->n_fhsize > NFS_SMALLFH) { 414 FREE((caddr_t)np->n_fhp, M_NFSBIGFH); 415 } 416 if (np->n_rucred) { 417 crfree(np->n_rucred); 418 np->n_rucred = NULL; 419 } 420 if (np->n_wucred) { 421 crfree(np->n_wucred); 422 np->n_wucred = NULL; 423 } 424 vp->v_data = NULL; 425 426 lwkt_reltoken(&nmp->nm_token); 427 zfree(nfsnode_zone, np); 428 429 return (0); 430 } 431 432