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 1.10 2004/04/19 16:33:49 cpressey 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(void) 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, NULL, 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, NULL, LK_EXCLUSIVE | LK_RETRY, td); 186 187 return (0); 188 } 189 190 /* 191 * nfs_inactive(struct vnode *a_vp, struct thread *a_td) 192 */ 193 int 194 nfs_inactive(struct vop_inactive_args *ap) 195 { 196 struct nfsnode *np; 197 struct sillyrename *sp; 198 199 np = VTONFS(ap->a_vp); 200 if (prtactive && ap->a_vp->v_usecount != 0) 201 vprint("nfs_inactive: pushing active", ap->a_vp); 202 if (ap->a_vp->v_type != VDIR) { 203 sp = np->n_sillyrename; 204 np->n_sillyrename = (struct sillyrename *)0; 205 } else 206 sp = (struct sillyrename *)0; 207 if (sp) { 208 /* 209 * We need a reference to keep the vnode from being 210 * recycled by getnewvnode while we do the I/O 211 * associated with discarding the buffers unless we 212 * are being forcibly unmounted in which case we already 213 * have our own reference. 214 */ 215 if (ap->a_vp->v_usecount > 0) 216 (void) nfs_vinvalbuf(ap->a_vp, 0, ap->a_td, 1); 217 else if (vget(ap->a_vp, NULL, 0, ap->a_td)) 218 panic("nfs_inactive: lost vnode"); 219 else { 220 (void) nfs_vinvalbuf(ap->a_vp, 0, ap->a_td, 1); 221 vrele(ap->a_vp); 222 } 223 /* 224 * Remove the silly file that was rename'd earlier 225 */ 226 nfs_removeit(sp); 227 crfree(sp->s_cred); 228 vrele(sp->s_dvp); 229 FREE((caddr_t)sp, M_NFSREQ); 230 } 231 np->n_flag &= (NMODIFIED | NFLUSHINPROG | NFLUSHWANT | NQNFSEVICTED | 232 NQNFSNONCACHE | NQNFSWRITE); 233 VOP_UNLOCK(ap->a_vp, NULL, 0, ap->a_td); 234 return (0); 235 } 236 237 /* 238 * Reclaim an nfsnode so that it can be used for other purposes. 239 * 240 * nfs_reclaim(struct vnode *a_vp) 241 */ 242 int 243 nfs_reclaim(struct vop_reclaim_args *ap) 244 { 245 struct vnode *vp = ap->a_vp; 246 struct nfsnode *np = VTONFS(vp); 247 struct nfsmount *nmp = VFSTONFS(vp->v_mount); 248 struct nfsdmap *dp, *dp2; 249 250 if (prtactive && vp->v_usecount != 0) 251 vprint("nfs_reclaim: pushing active", vp); 252 253 if (np->n_hash.le_prev != NULL) 254 LIST_REMOVE(np, n_hash); 255 256 /* 257 * For nqnfs, take it off the timer queue as required. 258 */ 259 if ((nmp->nm_flag & NFSMNT_NQNFS) && np->n_timer.cqe_next != 0) { 260 CIRCLEQ_REMOVE(&nmp->nm_timerhead, np, n_timer); 261 } 262 263 /* 264 * Free up any directory cookie structures and 265 * large file handle structures that might be associated with 266 * this nfs node. 267 */ 268 if (vp->v_type == VDIR) { 269 dp = np->n_cookies.lh_first; 270 while (dp) { 271 dp2 = dp; 272 dp = dp->ndm_list.le_next; 273 FREE((caddr_t)dp2, M_NFSDIROFF); 274 } 275 } 276 if (np->n_fhsize > NFS_SMALLFH) { 277 FREE((caddr_t)np->n_fhp, M_NFSBIGFH); 278 } 279 if (np->n_rucred) { 280 crfree(np->n_rucred); 281 np->n_rucred = NULL; 282 } 283 if (np->n_wucred) { 284 crfree(np->n_wucred); 285 np->n_wucred = NULL; 286 } 287 288 cache_purge(vp); 289 zfree(nfsnode_zone, vp->v_data); 290 vp->v_data = (void *)0; 291 return (0); 292 } 293 294 #if 0 295 /* 296 * Lock an nfsnode 297 * 298 * nfs_lock(struct vnode *a_vp) 299 */ 300 int 301 nfs_lock(struct vop_lock_args *ap) 302 { 303 struct vnode *vp = ap->a_vp; 304 305 /* 306 * Ugh, another place where interruptible mounts will get hung. 307 * If you make this sleep interruptible, then you have to fix all 308 * the VOP_LOCK() calls to expect interruptibility. 309 */ 310 while (vp->v_flag & VXLOCK) { 311 vp->v_flag |= VXWANT; 312 (void) tsleep((caddr_t)vp, 0, "nfslck", 0); 313 } 314 if (vp->v_tag == VT_NON) 315 return (ENOENT); 316 317 #if 0 318 /* 319 * Only lock regular files. If a server crashed while we were 320 * holding a directory lock, we could easily end up sleeping 321 * until the server rebooted while holding a lock on the root. 322 * Locks are only needed for protecting critical sections in 323 * VMIO at the moment. 324 * New vnodes will have type VNON but they should be locked 325 * since they may become VREG. This is checked in loadattrcache 326 * and unwanted locks are released there. 327 */ 328 if (vp->v_type == VREG || vp->v_type == VNON) { 329 while (np->n_flag & NLOCKED) { 330 np->n_flag |= NWANTED; 331 (void) tsleep((caddr_t) np, 0, "nfslck2", 0); 332 /* 333 * If the vnode has transmuted into a VDIR while we 334 * were asleep, then skip the lock. 335 */ 336 if (vp->v_type != VREG && vp->v_type != VNON) 337 return (0); 338 } 339 np->n_flag |= NLOCKED; 340 } 341 #endif 342 343 return (0); 344 } 345 346 /* 347 * Unlock an nfsnode 348 * 349 * nfs_unlock(struct vnode *a_vp) 350 */ 351 int 352 nfs_unlock(struct vop_unlock_args *ap) 353 { 354 #if 0 355 struct vnode* vp = ap->a_vp; 356 struct nfsnode* np = VTONFS(vp); 357 358 if (vp->v_type == VREG || vp->v_type == VNON) { 359 if (!(np->n_flag & NLOCKED)) 360 panic("nfs_unlock: nfsnode not locked"); 361 np->n_flag &= ~NLOCKED; 362 if (np->n_flag & NWANTED) { 363 np->n_flag &= ~NWANTED; 364 wakeup((caddr_t) np); 365 } 366 } 367 #endif 368 369 return (0); 370 } 371 372 /* 373 * Check for a locked nfsnode 374 * 375 * nfs_islocked(struct vnode *a_vp, struct thread *a_td) 376 */ 377 int 378 nfs_islocked(struct vop_islocked_args *ap) 379 { 380 return VTONFS(ap->a_vp)->n_flag & NLOCKED ? 1 : 0; 381 } 382 #endif 383 384