vfs_vnode.c revision 1.5.2.5
1 1.5.2.5 rmind /* $NetBSD: vfs_vnode.c,v 1.5.2.5 2011/05/30 14:57:48 rmind Exp $ */ 2 1.5.2.2 rmind 3 1.5.2.2 rmind /*- 4 1.5.2.2 rmind * Copyright (c) 1997-2011 The NetBSD Foundation, Inc. 5 1.5.2.2 rmind * All rights reserved. 6 1.5.2.2 rmind * 7 1.5.2.2 rmind * This code is derived from software contributed to The NetBSD Foundation 8 1.5.2.2 rmind * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility, 9 1.5.2.2 rmind * NASA Ames Research Center, by Charles M. Hannum, and by Andrew Doran. 10 1.5.2.2 rmind * 11 1.5.2.2 rmind * Redistribution and use in source and binary forms, with or without 12 1.5.2.2 rmind * modification, are permitted provided that the following conditions 13 1.5.2.2 rmind * are met: 14 1.5.2.2 rmind * 1. Redistributions of source code must retain the above copyright 15 1.5.2.2 rmind * notice, this list of conditions and the following disclaimer. 16 1.5.2.2 rmind * 2. Redistributions in binary form must reproduce the above copyright 17 1.5.2.2 rmind * notice, this list of conditions and the following disclaimer in the 18 1.5.2.2 rmind * documentation and/or other materials provided with the distribution. 19 1.5.2.2 rmind * 20 1.5.2.2 rmind * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 21 1.5.2.2 rmind * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 22 1.5.2.2 rmind * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 23 1.5.2.2 rmind * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 24 1.5.2.2 rmind * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 25 1.5.2.2 rmind * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 26 1.5.2.2 rmind * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 27 1.5.2.2 rmind * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 28 1.5.2.2 rmind * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 29 1.5.2.2 rmind * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 30 1.5.2.2 rmind * POSSIBILITY OF SUCH DAMAGE. 31 1.5.2.2 rmind */ 32 1.5.2.2 rmind 33 1.5.2.2 rmind /* 34 1.5.2.2 rmind * Copyright (c) 1989, 1993 35 1.5.2.2 rmind * The Regents of the University of California. All rights reserved. 36 1.5.2.2 rmind * (c) UNIX System Laboratories, Inc. 37 1.5.2.2 rmind * All or some portions of this file are derived from material licensed 38 1.5.2.2 rmind * to the University of California by American Telephone and Telegraph 39 1.5.2.2 rmind * Co. or Unix System Laboratories, Inc. and are reproduced herein with 40 1.5.2.2 rmind * the permission of UNIX System Laboratories, Inc. 41 1.5.2.2 rmind * 42 1.5.2.2 rmind * Redistribution and use in source and binary forms, with or without 43 1.5.2.2 rmind * modification, are permitted provided that the following conditions 44 1.5.2.2 rmind * are met: 45 1.5.2.2 rmind * 1. Redistributions of source code must retain the above copyright 46 1.5.2.2 rmind * notice, this list of conditions and the following disclaimer. 47 1.5.2.2 rmind * 2. Redistributions in binary form must reproduce the above copyright 48 1.5.2.2 rmind * notice, this list of conditions and the following disclaimer in the 49 1.5.2.2 rmind * documentation and/or other materials provided with the distribution. 50 1.5.2.2 rmind * 3. Neither the name of the University nor the names of its contributors 51 1.5.2.2 rmind * may be used to endorse or promote products derived from this software 52 1.5.2.2 rmind * without specific prior written permission. 53 1.5.2.2 rmind * 54 1.5.2.2 rmind * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 55 1.5.2.2 rmind * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 56 1.5.2.2 rmind * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 57 1.5.2.2 rmind * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 58 1.5.2.2 rmind * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 59 1.5.2.2 rmind * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 60 1.5.2.2 rmind * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 61 1.5.2.2 rmind * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 62 1.5.2.2 rmind * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 63 1.5.2.2 rmind * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 64 1.5.2.2 rmind * SUCH DAMAGE. 65 1.5.2.2 rmind * 66 1.5.2.2 rmind * @(#)vfs_subr.c 8.13 (Berkeley) 4/18/94 67 1.5.2.2 rmind */ 68 1.5.2.2 rmind 69 1.5.2.2 rmind /* 70 1.5.2.2 rmind * Note on v_usecount and locking: 71 1.5.2.2 rmind * 72 1.5.2.2 rmind * At nearly all points it is known that v_usecount could be zero, the 73 1.5.2.2 rmind * vnode interlock will be held. 74 1.5.2.2 rmind * 75 1.5.2.2 rmind * To change v_usecount away from zero, the interlock must be held. To 76 1.5.2.2 rmind * change from a non-zero value to zero, again the interlock must be 77 1.5.2.2 rmind * held. 78 1.5.2.2 rmind * 79 1.5.2.2 rmind * There's a flag bit, VC_XLOCK, embedded in v_usecount. 80 1.5.2.2 rmind * To raise v_usecount, if the VC_XLOCK bit is set in it, the interlock 81 1.5.2.2 rmind * must be held. 82 1.5.2.2 rmind * To modify the VC_XLOCK bit, the interlock must be held. 83 1.5.2.2 rmind * We always keep the usecount (v_usecount & VC_MASK) non-zero while the 84 1.5.2.2 rmind * VC_XLOCK bit is set. 85 1.5.2.2 rmind * 86 1.5.2.2 rmind * Unless the VC_XLOCK bit is set, changing the usecount from a non-zero 87 1.5.2.2 rmind * value to a non-zero value can safely be done using atomic operations, 88 1.5.2.2 rmind * without the interlock held. 89 1.5.2.2 rmind * Even if the VC_XLOCK bit is set, decreasing the usecount to a non-zero 90 1.5.2.2 rmind * value can be done using atomic operations, without the interlock held. 91 1.5.2.2 rmind */ 92 1.5.2.2 rmind 93 1.5.2.2 rmind #include <sys/cdefs.h> 94 1.5.2.5 rmind __KERNEL_RCSID(0, "$NetBSD: vfs_vnode.c,v 1.5.2.5 2011/05/30 14:57:48 rmind Exp $"); 95 1.5.2.2 rmind 96 1.5.2.2 rmind #include <sys/param.h> 97 1.5.2.2 rmind #include <sys/kernel.h> 98 1.5.2.2 rmind 99 1.5.2.2 rmind #include <sys/atomic.h> 100 1.5.2.2 rmind #include <sys/buf.h> 101 1.5.2.2 rmind #include <sys/conf.h> 102 1.5.2.2 rmind #include <sys/device.h> 103 1.5.2.2 rmind #include <sys/kauth.h> 104 1.5.2.2 rmind #include <sys/kmem.h> 105 1.5.2.2 rmind #include <sys/kthread.h> 106 1.5.2.2 rmind #include <sys/module.h> 107 1.5.2.2 rmind #include <sys/mount.h> 108 1.5.2.2 rmind #include <sys/namei.h> 109 1.5.2.2 rmind #include <sys/syscallargs.h> 110 1.5.2.2 rmind #include <sys/sysctl.h> 111 1.5.2.2 rmind #include <sys/systm.h> 112 1.5.2.2 rmind #include <sys/vnode.h> 113 1.5.2.2 rmind #include <sys/wapbl.h> 114 1.5.2.2 rmind 115 1.5.2.2 rmind #include <uvm/uvm.h> 116 1.5.2.2 rmind #include <uvm/uvm_readahead.h> 117 1.5.2.2 rmind 118 1.5.2.2 rmind u_int numvnodes; 119 1.5.2.2 rmind 120 1.5.2.2 rmind static pool_cache_t vnode_cache; 121 1.5.2.2 rmind static kmutex_t vnode_free_list_lock; 122 1.5.2.2 rmind 123 1.5.2.2 rmind static vnodelst_t vnode_free_list; 124 1.5.2.2 rmind static vnodelst_t vnode_hold_list; 125 1.5.2.2 rmind static vnodelst_t vrele_list; 126 1.5.2.2 rmind 127 1.5.2.2 rmind static kmutex_t vrele_lock; 128 1.5.2.2 rmind static kcondvar_t vrele_cv; 129 1.5.2.2 rmind static lwp_t * vrele_lwp; 130 1.5.2.2 rmind static int vrele_pending; 131 1.5.2.2 rmind static int vrele_gen; 132 1.5.2.2 rmind 133 1.5.2.2 rmind static vnode_t * getcleanvnode(void); 134 1.5.2.2 rmind static void vrele_thread(void *); 135 1.5.2.2 rmind static void vpanic(vnode_t *, const char *); 136 1.5.2.2 rmind 137 1.5.2.2 rmind /* Routines having to do with the management of the vnode table. */ 138 1.5.2.2 rmind extern int (**dead_vnodeop_p)(void *); 139 1.5.2.2 rmind 140 1.5.2.2 rmind void 141 1.5.2.2 rmind vfs_vnode_sysinit(void) 142 1.5.2.2 rmind { 143 1.5.2.2 rmind int error; 144 1.5.2.2 rmind 145 1.5.2.2 rmind vnode_cache = pool_cache_init(sizeof(vnode_t), 0, 0, 0, "vnodepl", 146 1.5.2.2 rmind NULL, IPL_NONE, NULL, NULL, NULL); 147 1.5.2.2 rmind KASSERT(vnode_cache != NULL); 148 1.5.2.2 rmind 149 1.5.2.2 rmind mutex_init(&vnode_free_list_lock, MUTEX_DEFAULT, IPL_NONE); 150 1.5.2.2 rmind TAILQ_INIT(&vnode_free_list); 151 1.5.2.2 rmind TAILQ_INIT(&vnode_hold_list); 152 1.5.2.2 rmind TAILQ_INIT(&vrele_list); 153 1.5.2.2 rmind 154 1.5.2.2 rmind mutex_init(&vrele_lock, MUTEX_DEFAULT, IPL_NONE); 155 1.5.2.2 rmind cv_init(&vrele_cv, "vrele"); 156 1.5.2.2 rmind error = kthread_create(PRI_VM, KTHREAD_MPSAFE, NULL, vrele_thread, 157 1.5.2.2 rmind NULL, &vrele_lwp, "vrele"); 158 1.5.2.2 rmind KASSERT(error == 0); 159 1.5.2.2 rmind } 160 1.5.2.2 rmind 161 1.5.2.2 rmind /* 162 1.5.2.2 rmind * Allocate a new, uninitialized vnode. If 'mp' is non-NULL, this is a 163 1.5.2.2 rmind * marker vnode and we are prepared to wait for the allocation. 164 1.5.2.2 rmind */ 165 1.5.2.2 rmind vnode_t * 166 1.5.2.2 rmind vnalloc(struct mount *mp) 167 1.5.2.2 rmind { 168 1.5.2.2 rmind vnode_t *vp; 169 1.5.2.2 rmind 170 1.5.2.2 rmind vp = pool_cache_get(vnode_cache, (mp != NULL ? PR_WAITOK : PR_NOWAIT)); 171 1.5.2.2 rmind if (vp == NULL) { 172 1.5.2.2 rmind return NULL; 173 1.5.2.2 rmind } 174 1.5.2.2 rmind 175 1.5.2.2 rmind memset(vp, 0, sizeof(*vp)); 176 1.5.2.3 rmind uvm_obj_init(&vp->v_uobj, &uvm_vnodeops, true, 0); 177 1.5.2.2 rmind cv_init(&vp->v_cv, "vnode"); 178 1.5.2.2 rmind /* 179 1.5.2.2 rmind * Done by memset() above. 180 1.5.2.2 rmind * LIST_INIT(&vp->v_nclist); 181 1.5.2.2 rmind * LIST_INIT(&vp->v_dnclist); 182 1.5.2.2 rmind */ 183 1.5.2.2 rmind 184 1.5.2.2 rmind if (mp != NULL) { 185 1.5.2.2 rmind vp->v_mount = mp; 186 1.5.2.2 rmind vp->v_type = VBAD; 187 1.5.2.2 rmind vp->v_iflag = VI_MARKER; 188 1.5.2.2 rmind } else { 189 1.5.2.2 rmind rw_init(&vp->v_lock); 190 1.5.2.2 rmind } 191 1.5.2.2 rmind 192 1.5.2.2 rmind return vp; 193 1.5.2.2 rmind } 194 1.5.2.2 rmind 195 1.5.2.2 rmind /* 196 1.5.2.2 rmind * Free an unused, unreferenced vnode. 197 1.5.2.2 rmind */ 198 1.5.2.2 rmind void 199 1.5.2.2 rmind vnfree(vnode_t *vp) 200 1.5.2.2 rmind { 201 1.5.2.2 rmind 202 1.5.2.2 rmind KASSERT(vp->v_usecount == 0); 203 1.5.2.2 rmind 204 1.5.2.2 rmind if ((vp->v_iflag & VI_MARKER) == 0) { 205 1.5.2.2 rmind rw_destroy(&vp->v_lock); 206 1.5.2.2 rmind mutex_enter(&vnode_free_list_lock); 207 1.5.2.2 rmind numvnodes--; 208 1.5.2.2 rmind mutex_exit(&vnode_free_list_lock); 209 1.5.2.2 rmind } 210 1.5.2.2 rmind 211 1.5.2.3 rmind /* 212 1.5.2.3 rmind * Note: the vnode interlock will either be freed, of reference 213 1.5.2.3 rmind * dropped (if VI_LOCKSHARE was in use). 214 1.5.2.3 rmind */ 215 1.5.2.3 rmind uvm_obj_destroy(&vp->v_uobj, true); 216 1.5.2.2 rmind cv_destroy(&vp->v_cv); 217 1.5.2.2 rmind pool_cache_put(vnode_cache, vp); 218 1.5.2.2 rmind } 219 1.5.2.2 rmind 220 1.5.2.2 rmind /* 221 1.5.2.2 rmind * getcleanvnode: grab a vnode from freelist and clean it. 222 1.5.2.2 rmind * 223 1.5.2.2 rmind * => Releases vnode_free_list_lock. 224 1.5.2.2 rmind * => Returns referenced vnode on success. 225 1.5.2.2 rmind */ 226 1.5.2.2 rmind static vnode_t * 227 1.5.2.2 rmind getcleanvnode(void) 228 1.5.2.2 rmind { 229 1.5.2.2 rmind vnode_t *vp; 230 1.5.2.2 rmind vnodelst_t *listhd; 231 1.5.2.2 rmind 232 1.5.2.2 rmind KASSERT(mutex_owned(&vnode_free_list_lock)); 233 1.5.2.2 rmind retry: 234 1.5.2.2 rmind listhd = &vnode_free_list; 235 1.5.2.2 rmind try_nextlist: 236 1.5.2.2 rmind TAILQ_FOREACH(vp, listhd, v_freelist) { 237 1.5.2.2 rmind /* 238 1.5.2.2 rmind * It's safe to test v_usecount and v_iflag 239 1.5.2.2 rmind * without holding the interlock here, since 240 1.5.2.2 rmind * these vnodes should never appear on the 241 1.5.2.2 rmind * lists. 242 1.5.2.2 rmind */ 243 1.5.2.2 rmind KASSERT(vp->v_usecount == 0); 244 1.5.2.2 rmind KASSERT((vp->v_iflag & VI_CLEAN) == 0); 245 1.5.2.2 rmind KASSERT(vp->v_freelisthd == listhd); 246 1.5.2.2 rmind 247 1.5.2.2 rmind if (!mutex_tryenter(vp->v_interlock)) 248 1.5.2.2 rmind continue; 249 1.5.2.2 rmind if ((vp->v_iflag & VI_XLOCK) == 0) 250 1.5.2.2 rmind break; 251 1.5.2.2 rmind mutex_exit(vp->v_interlock); 252 1.5.2.2 rmind } 253 1.5.2.2 rmind 254 1.5.2.2 rmind if (vp == NULL) { 255 1.5.2.2 rmind if (listhd == &vnode_free_list) { 256 1.5.2.2 rmind listhd = &vnode_hold_list; 257 1.5.2.2 rmind goto try_nextlist; 258 1.5.2.2 rmind } 259 1.5.2.2 rmind mutex_exit(&vnode_free_list_lock); 260 1.5.2.2 rmind return NULL; 261 1.5.2.2 rmind } 262 1.5.2.2 rmind 263 1.5.2.2 rmind /* Remove it from the freelist. */ 264 1.5.2.2 rmind TAILQ_REMOVE(listhd, vp, v_freelist); 265 1.5.2.2 rmind vp->v_freelisthd = NULL; 266 1.5.2.2 rmind mutex_exit(&vnode_free_list_lock); 267 1.5.2.2 rmind 268 1.5.2.2 rmind KASSERT(vp->v_usecount == 0); 269 1.5.2.2 rmind 270 1.5.2.2 rmind /* 271 1.5.2.2 rmind * The vnode is still associated with a file system, so we must 272 1.5.2.2 rmind * clean it out before reusing it. We need to add a reference 273 1.5.2.2 rmind * before doing this. If the vnode gains another reference while 274 1.5.2.2 rmind * being cleaned out then we lose - retry. 275 1.5.2.2 rmind */ 276 1.5.2.2 rmind atomic_add_int(&vp->v_usecount, 1 + VC_XLOCK); 277 1.5.2.2 rmind vclean(vp, DOCLOSE); 278 1.5.2.2 rmind KASSERT(vp->v_usecount >= 1 + VC_XLOCK); 279 1.5.2.2 rmind atomic_add_int(&vp->v_usecount, -VC_XLOCK); 280 1.5.2.2 rmind if (vp->v_usecount == 1) { 281 1.5.2.2 rmind /* We're about to dirty it. */ 282 1.5.2.2 rmind vp->v_iflag &= ~VI_CLEAN; 283 1.5.2.2 rmind mutex_exit(vp->v_interlock); 284 1.5.2.2 rmind if (vp->v_type == VBLK || vp->v_type == VCHR) { 285 1.5.2.2 rmind spec_node_destroy(vp); 286 1.5.2.2 rmind } 287 1.5.2.2 rmind vp->v_type = VNON; 288 1.5.2.2 rmind } else { 289 1.5.2.2 rmind /* 290 1.5.2.2 rmind * Don't return to freelist - the holder of the last 291 1.5.2.2 rmind * reference will destroy it. 292 1.5.2.2 rmind */ 293 1.5.2.2 rmind vrelel(vp, 0); /* releases vp->v_interlock */ 294 1.5.2.2 rmind mutex_enter(&vnode_free_list_lock); 295 1.5.2.2 rmind goto retry; 296 1.5.2.2 rmind } 297 1.5.2.2 rmind 298 1.5.2.2 rmind KASSERT(vp->v_data == NULL); 299 1.5.2.2 rmind KASSERT(vp->v_uobj.uo_npages == 0); 300 1.5.2.2 rmind KASSERT(TAILQ_EMPTY(&vp->v_uobj.memq)); 301 1.5.2.2 rmind KASSERT(vp->v_numoutput == 0); 302 1.5.2.2 rmind KASSERT((vp->v_iflag & VI_ONWORKLST) == 0); 303 1.5.2.2 rmind 304 1.5.2.2 rmind return vp; 305 1.5.2.2 rmind } 306 1.5.2.2 rmind 307 1.5.2.2 rmind /* 308 1.5.2.2 rmind * getnewvnode: return the next vnode from the free list. 309 1.5.2.2 rmind * 310 1.5.2.2 rmind * => Returns referenced vnode, moved into the mount queue. 311 1.5.2.5 rmind * => Shares the interlock specified by 'slock', if it is not NULL. 312 1.5.2.2 rmind */ 313 1.5.2.2 rmind int 314 1.5.2.2 rmind getnewvnode(enum vtagtype tag, struct mount *mp, int (**vops)(void *), 315 1.5.2.5 rmind kmutex_t *slock, vnode_t **vpp) 316 1.5.2.2 rmind { 317 1.5.2.2 rmind struct uvm_object *uobj; 318 1.5.2.2 rmind static int toggle; 319 1.5.2.2 rmind vnode_t *vp; 320 1.5.2.2 rmind int error = 0, tryalloc; 321 1.5.2.2 rmind 322 1.5.2.2 rmind try_again: 323 1.5.2.2 rmind if (mp != NULL) { 324 1.5.2.2 rmind /* 325 1.5.2.2 rmind * Mark filesystem busy while we are creating a vnode. 326 1.5.2.2 rmind * If unmount is in progress, this will fail. 327 1.5.2.2 rmind */ 328 1.5.2.2 rmind error = vfs_busy(mp, NULL); 329 1.5.2.2 rmind if (error) 330 1.5.2.2 rmind return error; 331 1.5.2.2 rmind } 332 1.5.2.2 rmind 333 1.5.2.2 rmind /* 334 1.5.2.2 rmind * We must choose whether to allocate a new vnode or recycle an 335 1.5.2.2 rmind * existing one. The criterion for allocating a new one is that 336 1.5.2.2 rmind * the total number of vnodes is less than the number desired or 337 1.5.2.2 rmind * there are no vnodes on either free list. Generally we only 338 1.5.2.2 rmind * want to recycle vnodes that have no buffers associated with 339 1.5.2.2 rmind * them, so we look first on the vnode_free_list. If it is empty, 340 1.5.2.2 rmind * we next consider vnodes with referencing buffers on the 341 1.5.2.2 rmind * vnode_hold_list. The toggle ensures that half the time we 342 1.5.2.2 rmind * will use a buffer from the vnode_hold_list, and half the time 343 1.5.2.2 rmind * we will allocate a new one unless the list has grown to twice 344 1.5.2.2 rmind * the desired size. We are reticent to recycle vnodes from the 345 1.5.2.2 rmind * vnode_hold_list because we will lose the identity of all its 346 1.5.2.2 rmind * referencing buffers. 347 1.5.2.2 rmind */ 348 1.5.2.2 rmind 349 1.5.2.2 rmind vp = NULL; 350 1.5.2.2 rmind 351 1.5.2.2 rmind mutex_enter(&vnode_free_list_lock); 352 1.5.2.2 rmind 353 1.5.2.2 rmind toggle ^= 1; 354 1.5.2.2 rmind if (numvnodes > 2 * desiredvnodes) 355 1.5.2.2 rmind toggle = 0; 356 1.5.2.2 rmind 357 1.5.2.2 rmind tryalloc = numvnodes < desiredvnodes || 358 1.5.2.2 rmind (TAILQ_FIRST(&vnode_free_list) == NULL && 359 1.5.2.2 rmind (TAILQ_FIRST(&vnode_hold_list) == NULL || toggle)); 360 1.5.2.2 rmind 361 1.5.2.2 rmind if (tryalloc) { 362 1.5.2.2 rmind /* Allocate a new vnode. */ 363 1.5.2.2 rmind numvnodes++; 364 1.5.2.2 rmind mutex_exit(&vnode_free_list_lock); 365 1.5.2.2 rmind if ((vp = vnalloc(NULL)) == NULL) { 366 1.5.2.2 rmind mutex_enter(&vnode_free_list_lock); 367 1.5.2.2 rmind numvnodes--; 368 1.5.2.2 rmind } else 369 1.5.2.2 rmind vp->v_usecount = 1; 370 1.5.2.2 rmind } 371 1.5.2.2 rmind 372 1.5.2.2 rmind if (vp == NULL) { 373 1.5.2.2 rmind /* Recycle and get vnode clean. */ 374 1.5.2.2 rmind vp = getcleanvnode(); 375 1.5.2.2 rmind if (vp == NULL) { 376 1.5.2.2 rmind if (mp != NULL) { 377 1.5.2.2 rmind vfs_unbusy(mp, false, NULL); 378 1.5.2.2 rmind } 379 1.5.2.2 rmind if (tryalloc) { 380 1.5.2.2 rmind printf("WARNING: unable to allocate new " 381 1.5.2.2 rmind "vnode, retrying...\n"); 382 1.5.2.2 rmind kpause("newvn", false, hz, NULL); 383 1.5.2.2 rmind goto try_again; 384 1.5.2.2 rmind } 385 1.5.2.2 rmind tablefull("vnode", "increase kern.maxvnodes or NVNODE"); 386 1.5.2.2 rmind *vpp = 0; 387 1.5.2.2 rmind return ENFILE; 388 1.5.2.2 rmind } 389 1.5.2.5 rmind if ((vp->v_iflag & VI_LOCKSHARE) != 0 || slock) { 390 1.5.2.3 rmind /* We must remove vnode from the old mount point. */ 391 1.5.2.3 rmind if (vp->v_mount) { 392 1.5.2.3 rmind vfs_insmntque(vp, NULL); 393 1.5.2.3 rmind } 394 1.5.2.3 rmind /* Allocate a new interlock, if it was shared. */ 395 1.5.2.3 rmind if (vp->v_iflag & VI_LOCKSHARE) { 396 1.5.2.3 rmind uvm_obj_setlock(&vp->v_uobj, NULL); 397 1.5.2.3 rmind vp->v_iflag &= ~VI_LOCKSHARE; 398 1.5.2.3 rmind } 399 1.5.2.3 rmind } 400 1.5.2.2 rmind vp->v_iflag = 0; 401 1.5.2.2 rmind vp->v_vflag = 0; 402 1.5.2.2 rmind vp->v_uflag = 0; 403 1.5.2.2 rmind vp->v_socket = NULL; 404 1.5.2.2 rmind } 405 1.5.2.2 rmind 406 1.5.2.2 rmind KASSERT(vp->v_usecount == 1); 407 1.5.2.2 rmind KASSERT(vp->v_freelisthd == NULL); 408 1.5.2.2 rmind KASSERT(LIST_EMPTY(&vp->v_nclist)); 409 1.5.2.2 rmind KASSERT(LIST_EMPTY(&vp->v_dnclist)); 410 1.5.2.2 rmind 411 1.5.2.2 rmind /* Initialize vnode. */ 412 1.5.2.2 rmind vp->v_type = VNON; 413 1.5.2.2 rmind vp->v_tag = tag; 414 1.5.2.2 rmind vp->v_op = vops; 415 1.5.2.2 rmind vp->v_data = NULL; 416 1.5.2.2 rmind 417 1.5.2.2 rmind uobj = &vp->v_uobj; 418 1.5.2.2 rmind KASSERT(uobj->pgops == &uvm_vnodeops); 419 1.5.2.2 rmind KASSERT(uobj->uo_npages == 0); 420 1.5.2.2 rmind KASSERT(TAILQ_FIRST(&uobj->memq) == NULL); 421 1.5.2.2 rmind vp->v_size = vp->v_writesize = VSIZENOTSET; 422 1.5.2.2 rmind 423 1.5.2.3 rmind /* Share the vnode_t::v_interlock, if requested. */ 424 1.5.2.5 rmind if (slock) { 425 1.5.2.3 rmind /* Set the interlock and mark that it is shared. */ 426 1.5.2.3 rmind KASSERT(vp->v_mount == NULL); 427 1.5.2.5 rmind mutex_obj_hold(slock); 428 1.5.2.5 rmind uvm_obj_setlock(&vp->v_uobj, slock); 429 1.5.2.5 rmind KASSERT(vp->v_interlock == slock); 430 1.5.2.3 rmind vp->v_iflag |= VI_LOCKSHARE; 431 1.5.2.3 rmind } 432 1.5.2.3 rmind 433 1.5.2.2 rmind /* Finally, move vnode into the mount queue. */ 434 1.5.2.2 rmind vfs_insmntque(vp, mp); 435 1.5.2.2 rmind 436 1.5.2.2 rmind if (mp != NULL) { 437 1.5.2.2 rmind if ((mp->mnt_iflag & IMNT_MPSAFE) != 0) 438 1.5.2.2 rmind vp->v_vflag |= VV_MPSAFE; 439 1.5.2.2 rmind vfs_unbusy(mp, true, NULL); 440 1.5.2.2 rmind } 441 1.5.2.2 rmind 442 1.5.2.2 rmind *vpp = vp; 443 1.5.2.2 rmind return 0; 444 1.5.2.2 rmind } 445 1.5.2.2 rmind 446 1.5.2.2 rmind /* 447 1.5.2.2 rmind * This is really just the reverse of getnewvnode(). Needed for 448 1.5.2.2 rmind * VFS_VGET functions who may need to push back a vnode in case 449 1.5.2.2 rmind * of a locking race. 450 1.5.2.2 rmind */ 451 1.5.2.2 rmind void 452 1.5.2.2 rmind ungetnewvnode(vnode_t *vp) 453 1.5.2.2 rmind { 454 1.5.2.2 rmind 455 1.5.2.2 rmind KASSERT(vp->v_usecount == 1); 456 1.5.2.2 rmind KASSERT(vp->v_data == NULL); 457 1.5.2.2 rmind KASSERT(vp->v_freelisthd == NULL); 458 1.5.2.2 rmind 459 1.5.2.2 rmind mutex_enter(vp->v_interlock); 460 1.5.2.2 rmind vp->v_iflag |= VI_CLEAN; 461 1.5.2.2 rmind vrelel(vp, 0); 462 1.5.2.2 rmind } 463 1.5.2.2 rmind 464 1.5.2.2 rmind /* 465 1.5.2.2 rmind * Remove a vnode from its freelist. 466 1.5.2.2 rmind */ 467 1.5.2.2 rmind void 468 1.5.2.2 rmind vremfree(vnode_t *vp) 469 1.5.2.2 rmind { 470 1.5.2.2 rmind 471 1.5.2.2 rmind KASSERT(mutex_owned(vp->v_interlock)); 472 1.5.2.2 rmind KASSERT(vp->v_usecount == 0); 473 1.5.2.2 rmind 474 1.5.2.2 rmind /* 475 1.5.2.2 rmind * Note that the reference count must not change until 476 1.5.2.2 rmind * the vnode is removed. 477 1.5.2.2 rmind */ 478 1.5.2.2 rmind mutex_enter(&vnode_free_list_lock); 479 1.5.2.2 rmind if (vp->v_holdcnt > 0) { 480 1.5.2.2 rmind KASSERT(vp->v_freelisthd == &vnode_hold_list); 481 1.5.2.2 rmind } else { 482 1.5.2.2 rmind KASSERT(vp->v_freelisthd == &vnode_free_list); 483 1.5.2.2 rmind } 484 1.5.2.2 rmind TAILQ_REMOVE(vp->v_freelisthd, vp, v_freelist); 485 1.5.2.2 rmind vp->v_freelisthd = NULL; 486 1.5.2.2 rmind mutex_exit(&vnode_free_list_lock); 487 1.5.2.2 rmind } 488 1.5.2.2 rmind 489 1.5.2.2 rmind /* 490 1.5.2.2 rmind * Try to gain a reference to a vnode, without acquiring its interlock. 491 1.5.2.2 rmind * The caller must hold a lock that will prevent the vnode from being 492 1.5.2.2 rmind * recycled or freed. 493 1.5.2.2 rmind */ 494 1.5.2.2 rmind bool 495 1.5.2.2 rmind vtryget(vnode_t *vp) 496 1.5.2.2 rmind { 497 1.5.2.2 rmind u_int use, next; 498 1.5.2.2 rmind 499 1.5.2.2 rmind /* 500 1.5.2.2 rmind * If the vnode is being freed, don't make life any harder 501 1.5.2.2 rmind * for vclean() by adding another reference without waiting. 502 1.5.2.2 rmind * This is not strictly necessary, but we'll do it anyway. 503 1.5.2.2 rmind */ 504 1.5.2.2 rmind if (__predict_false((vp->v_iflag & VI_XLOCK) != 0)) { 505 1.5.2.2 rmind return false; 506 1.5.2.2 rmind } 507 1.5.2.2 rmind for (use = vp->v_usecount;; use = next) { 508 1.5.2.2 rmind if (use == 0 || __predict_false((use & VC_XLOCK) != 0)) { 509 1.5.2.2 rmind /* Need interlock held if first reference. */ 510 1.5.2.2 rmind return false; 511 1.5.2.2 rmind } 512 1.5.2.2 rmind next = atomic_cas_uint(&vp->v_usecount, use, use + 1); 513 1.5.2.2 rmind if (__predict_true(next == use)) { 514 1.5.2.2 rmind return true; 515 1.5.2.2 rmind } 516 1.5.2.2 rmind } 517 1.5.2.2 rmind } 518 1.5.2.2 rmind 519 1.5.2.2 rmind /* 520 1.5.2.2 rmind * vget: get a particular vnode from the free list, increment its reference 521 1.5.2.2 rmind * count and lock it. 522 1.5.2.2 rmind * 523 1.5.2.2 rmind * => Should be called with v_interlock held. 524 1.5.2.2 rmind * 525 1.5.2.2 rmind * If VI_XLOCK is set, the vnode is being eliminated in vgone()/vclean(). 526 1.5.2.2 rmind * In that case, we cannot grab the vnode, so the process is awakened when 527 1.5.2.2 rmind * the transition is completed, and an error returned to indicate that the 528 1.5.2.2 rmind * vnode is no longer usable (e.g. changed to a new file system type). 529 1.5.2.2 rmind */ 530 1.5.2.2 rmind int 531 1.5.2.2 rmind vget(vnode_t *vp, int flags) 532 1.5.2.2 rmind { 533 1.5.2.2 rmind int error = 0; 534 1.5.2.2 rmind 535 1.5.2.2 rmind KASSERT((vp->v_iflag & VI_MARKER) == 0); 536 1.5.2.2 rmind KASSERT(mutex_owned(vp->v_interlock)); 537 1.5.2.2 rmind KASSERT((flags & ~(LK_SHARED|LK_EXCLUSIVE|LK_NOWAIT)) == 0); 538 1.5.2.2 rmind 539 1.5.2.2 rmind /* 540 1.5.2.2 rmind * Before adding a reference, we must remove the vnode 541 1.5.2.2 rmind * from its freelist. 542 1.5.2.2 rmind */ 543 1.5.2.2 rmind if (vp->v_usecount == 0) { 544 1.5.2.2 rmind vremfree(vp); 545 1.5.2.2 rmind vp->v_usecount = 1; 546 1.5.2.2 rmind } else { 547 1.5.2.2 rmind atomic_inc_uint(&vp->v_usecount); 548 1.5.2.2 rmind } 549 1.5.2.2 rmind 550 1.5.2.2 rmind /* 551 1.5.2.2 rmind * If the vnode is in the process of being cleaned out for 552 1.5.2.2 rmind * another use, we wait for the cleaning to finish and then 553 1.5.2.2 rmind * return failure. Cleaning is determined by checking if 554 1.5.2.2 rmind * the VI_XLOCK flag is set. 555 1.5.2.2 rmind */ 556 1.5.2.2 rmind if ((vp->v_iflag & VI_XLOCK) != 0) { 557 1.5.2.2 rmind if ((flags & LK_NOWAIT) != 0) { 558 1.5.2.2 rmind vrelel(vp, 0); 559 1.5.2.2 rmind return EBUSY; 560 1.5.2.2 rmind } 561 1.5.2.2 rmind vwait(vp, VI_XLOCK); 562 1.5.2.2 rmind vrelel(vp, 0); 563 1.5.2.2 rmind return ENOENT; 564 1.5.2.2 rmind } 565 1.5.2.2 rmind 566 1.5.2.2 rmind /* 567 1.5.2.2 rmind * Ok, we got it in good shape. Just locking left. 568 1.5.2.2 rmind */ 569 1.5.2.2 rmind KASSERT((vp->v_iflag & VI_CLEAN) == 0); 570 1.5.2.2 rmind mutex_exit(vp->v_interlock); 571 1.5.2.2 rmind if (flags & (LK_EXCLUSIVE | LK_SHARED)) { 572 1.5.2.2 rmind error = vn_lock(vp, flags); 573 1.5.2.2 rmind if (error != 0) { 574 1.5.2.2 rmind vrele(vp); 575 1.5.2.2 rmind } 576 1.5.2.2 rmind } 577 1.5.2.2 rmind return error; 578 1.5.2.2 rmind } 579 1.5.2.2 rmind 580 1.5.2.2 rmind /* 581 1.5.2.2 rmind * vput: unlock and release the reference. 582 1.5.2.2 rmind */ 583 1.5.2.2 rmind void 584 1.5.2.2 rmind vput(vnode_t *vp) 585 1.5.2.2 rmind { 586 1.5.2.2 rmind 587 1.5.2.2 rmind KASSERT((vp->v_iflag & VI_MARKER) == 0); 588 1.5.2.2 rmind 589 1.5.2.2 rmind VOP_UNLOCK(vp); 590 1.5.2.2 rmind vrele(vp); 591 1.5.2.2 rmind } 592 1.5.2.2 rmind 593 1.5.2.2 rmind /* 594 1.5.2.2 rmind * Try to drop reference on a vnode. Abort if we are releasing the 595 1.5.2.2 rmind * last reference. Note: this _must_ succeed if not the last reference. 596 1.5.2.2 rmind */ 597 1.5.2.2 rmind static inline bool 598 1.5.2.2 rmind vtryrele(vnode_t *vp) 599 1.5.2.2 rmind { 600 1.5.2.2 rmind u_int use, next; 601 1.5.2.2 rmind 602 1.5.2.2 rmind for (use = vp->v_usecount;; use = next) { 603 1.5.2.2 rmind if (use == 1) { 604 1.5.2.2 rmind return false; 605 1.5.2.2 rmind } 606 1.5.2.2 rmind KASSERT((use & VC_MASK) > 1); 607 1.5.2.2 rmind next = atomic_cas_uint(&vp->v_usecount, use, use - 1); 608 1.5.2.2 rmind if (__predict_true(next == use)) { 609 1.5.2.2 rmind return true; 610 1.5.2.2 rmind } 611 1.5.2.2 rmind } 612 1.5.2.2 rmind } 613 1.5.2.2 rmind 614 1.5.2.2 rmind /* 615 1.5.2.2 rmind * Vnode release. If reference count drops to zero, call inactive 616 1.5.2.2 rmind * routine and either return to freelist or free to the pool. 617 1.5.2.2 rmind */ 618 1.5.2.2 rmind void 619 1.5.2.2 rmind vrelel(vnode_t *vp, int flags) 620 1.5.2.2 rmind { 621 1.5.2.2 rmind bool recycle, defer; 622 1.5.2.2 rmind int error; 623 1.5.2.2 rmind 624 1.5.2.2 rmind KASSERT(mutex_owned(vp->v_interlock)); 625 1.5.2.2 rmind KASSERT((vp->v_iflag & VI_MARKER) == 0); 626 1.5.2.2 rmind KASSERT(vp->v_freelisthd == NULL); 627 1.5.2.2 rmind 628 1.5.2.2 rmind if (__predict_false(vp->v_op == dead_vnodeop_p && 629 1.5.2.2 rmind (vp->v_iflag & (VI_CLEAN|VI_XLOCK)) == 0)) { 630 1.5.2.2 rmind vpanic(vp, "dead but not clean"); 631 1.5.2.2 rmind } 632 1.5.2.2 rmind 633 1.5.2.2 rmind /* 634 1.5.2.2 rmind * If not the last reference, just drop the reference count 635 1.5.2.2 rmind * and unlock. 636 1.5.2.2 rmind */ 637 1.5.2.2 rmind if (vtryrele(vp)) { 638 1.5.2.2 rmind vp->v_iflag |= VI_INACTREDO; 639 1.5.2.2 rmind mutex_exit(vp->v_interlock); 640 1.5.2.2 rmind return; 641 1.5.2.2 rmind } 642 1.5.2.2 rmind if (vp->v_usecount <= 0 || vp->v_writecount != 0) { 643 1.5.2.2 rmind vpanic(vp, "vrelel: bad ref count"); 644 1.5.2.2 rmind } 645 1.5.2.2 rmind 646 1.5.2.2 rmind KASSERT((vp->v_iflag & VI_XLOCK) == 0); 647 1.5.2.2 rmind 648 1.5.2.2 rmind /* 649 1.5.2.2 rmind * If not clean, deactivate the vnode, but preserve 650 1.5.2.2 rmind * our reference across the call to VOP_INACTIVE(). 651 1.5.2.2 rmind */ 652 1.5.2.2 rmind retry: 653 1.5.2.2 rmind if ((vp->v_iflag & VI_CLEAN) == 0) { 654 1.5.2.2 rmind recycle = false; 655 1.5.2.2 rmind vp->v_iflag |= VI_INACTNOW; 656 1.5.2.2 rmind 657 1.5.2.2 rmind /* 658 1.5.2.2 rmind * XXX This ugly block can be largely eliminated if 659 1.5.2.2 rmind * locking is pushed down into the file systems. 660 1.5.2.2 rmind * 661 1.5.2.2 rmind * Defer vnode release to vrele_thread if caller 662 1.5.2.2 rmind * requests it explicitly. 663 1.5.2.2 rmind */ 664 1.5.2.2 rmind if ((curlwp == uvm.pagedaemon_lwp) || 665 1.5.2.2 rmind (flags & VRELEL_ASYNC_RELE) != 0) { 666 1.5.2.2 rmind /* The pagedaemon can't wait around; defer. */ 667 1.5.2.2 rmind defer = true; 668 1.5.2.2 rmind } else if (curlwp == vrele_lwp) { 669 1.5.2.2 rmind /* We have to try harder. */ 670 1.5.2.2 rmind vp->v_iflag &= ~VI_INACTREDO; 671 1.5.2.2 rmind mutex_exit(vp->v_interlock); 672 1.5.2.2 rmind error = vn_lock(vp, LK_EXCLUSIVE); 673 1.5.2.2 rmind if (error != 0) { 674 1.5.2.2 rmind /* XXX */ 675 1.5.2.2 rmind vpanic(vp, "vrele: unable to lock %p"); 676 1.5.2.2 rmind } 677 1.5.2.2 rmind defer = false; 678 1.5.2.2 rmind } else if ((vp->v_iflag & VI_LAYER) != 0) { 679 1.5.2.2 rmind /* 680 1.5.2.2 rmind * Acquiring the stack's lock in vclean() even 681 1.5.2.2 rmind * for an honest vput/vrele is dangerous because 682 1.5.2.2 rmind * our caller may hold other vnode locks; defer. 683 1.5.2.2 rmind */ 684 1.5.2.2 rmind defer = true; 685 1.5.2.2 rmind } else { 686 1.5.2.2 rmind /* If we can't acquire the lock, then defer. */ 687 1.5.2.2 rmind vp->v_iflag &= ~VI_INACTREDO; 688 1.5.2.2 rmind mutex_exit(vp->v_interlock); 689 1.5.2.2 rmind error = vn_lock(vp, LK_EXCLUSIVE | LK_NOWAIT); 690 1.5.2.2 rmind if (error != 0) { 691 1.5.2.2 rmind defer = true; 692 1.5.2.2 rmind mutex_enter(vp->v_interlock); 693 1.5.2.2 rmind } else { 694 1.5.2.2 rmind defer = false; 695 1.5.2.2 rmind } 696 1.5.2.2 rmind } 697 1.5.2.2 rmind 698 1.5.2.2 rmind if (defer) { 699 1.5.2.2 rmind /* 700 1.5.2.2 rmind * Defer reclaim to the kthread; it's not safe to 701 1.5.2.2 rmind * clean it here. We donate it our last reference. 702 1.5.2.2 rmind */ 703 1.5.2.2 rmind KASSERT(mutex_owned(vp->v_interlock)); 704 1.5.2.2 rmind KASSERT((vp->v_iflag & VI_INACTPEND) == 0); 705 1.5.2.2 rmind vp->v_iflag &= ~VI_INACTNOW; 706 1.5.2.2 rmind vp->v_iflag |= VI_INACTPEND; 707 1.5.2.2 rmind mutex_enter(&vrele_lock); 708 1.5.2.2 rmind TAILQ_INSERT_TAIL(&vrele_list, vp, v_freelist); 709 1.5.2.2 rmind if (++vrele_pending > (desiredvnodes >> 8)) 710 1.5.2.2 rmind cv_signal(&vrele_cv); 711 1.5.2.2 rmind mutex_exit(&vrele_lock); 712 1.5.2.2 rmind mutex_exit(vp->v_interlock); 713 1.5.2.2 rmind return; 714 1.5.2.2 rmind } 715 1.5.2.2 rmind 716 1.5.2.2 rmind #ifdef DIAGNOSTIC 717 1.5.2.2 rmind if ((vp->v_type == VBLK || vp->v_type == VCHR) && 718 1.5.2.2 rmind vp->v_specnode != NULL && vp->v_specnode->sn_opencnt != 0) { 719 1.5.2.2 rmind vprint("vrelel: missing VOP_CLOSE()", vp); 720 1.5.2.2 rmind } 721 1.5.2.2 rmind #endif 722 1.5.2.2 rmind 723 1.5.2.2 rmind /* 724 1.5.2.2 rmind * The vnode can gain another reference while being 725 1.5.2.2 rmind * deactivated. If VOP_INACTIVE() indicates that 726 1.5.2.2 rmind * the described file has been deleted, then recycle 727 1.5.2.2 rmind * the vnode irrespective of additional references. 728 1.5.2.2 rmind * Another thread may be waiting to re-use the on-disk 729 1.5.2.2 rmind * inode. 730 1.5.2.2 rmind * 731 1.5.2.2 rmind * Note that VOP_INACTIVE() will drop the vnode lock. 732 1.5.2.2 rmind */ 733 1.5.2.2 rmind VOP_INACTIVE(vp, &recycle); 734 1.5.2.2 rmind mutex_enter(vp->v_interlock); 735 1.5.2.2 rmind vp->v_iflag &= ~VI_INACTNOW; 736 1.5.2.2 rmind if (!recycle) { 737 1.5.2.2 rmind if (vtryrele(vp)) { 738 1.5.2.2 rmind mutex_exit(vp->v_interlock); 739 1.5.2.2 rmind return; 740 1.5.2.2 rmind } 741 1.5.2.2 rmind 742 1.5.2.2 rmind /* 743 1.5.2.2 rmind * If we grew another reference while 744 1.5.2.2 rmind * VOP_INACTIVE() was underway, retry. 745 1.5.2.2 rmind */ 746 1.5.2.2 rmind if ((vp->v_iflag & VI_INACTREDO) != 0) { 747 1.5.2.2 rmind goto retry; 748 1.5.2.2 rmind } 749 1.5.2.2 rmind } 750 1.5.2.2 rmind 751 1.5.2.2 rmind /* Take care of space accounting. */ 752 1.5.2.2 rmind if (vp->v_iflag & VI_EXECMAP) { 753 1.5.2.2 rmind atomic_add_int(&uvmexp.execpages, 754 1.5.2.2 rmind -vp->v_uobj.uo_npages); 755 1.5.2.2 rmind atomic_add_int(&uvmexp.filepages, 756 1.5.2.2 rmind vp->v_uobj.uo_npages); 757 1.5.2.2 rmind } 758 1.5.2.2 rmind vp->v_iflag &= ~(VI_TEXT|VI_EXECMAP|VI_WRMAP); 759 1.5.2.2 rmind vp->v_vflag &= ~VV_MAPPED; 760 1.5.2.2 rmind 761 1.5.2.2 rmind /* 762 1.5.2.2 rmind * Recycle the vnode if the file is now unused (unlinked), 763 1.5.2.2 rmind * otherwise just free it. 764 1.5.2.2 rmind */ 765 1.5.2.2 rmind if (recycle) { 766 1.5.2.2 rmind vclean(vp, DOCLOSE); 767 1.5.2.2 rmind } 768 1.5.2.2 rmind KASSERT(vp->v_usecount > 0); 769 1.5.2.2 rmind } 770 1.5.2.2 rmind 771 1.5.2.2 rmind if (atomic_dec_uint_nv(&vp->v_usecount) != 0) { 772 1.5.2.2 rmind /* Gained another reference while being reclaimed. */ 773 1.5.2.2 rmind mutex_exit(vp->v_interlock); 774 1.5.2.2 rmind return; 775 1.5.2.2 rmind } 776 1.5.2.2 rmind 777 1.5.2.2 rmind if ((vp->v_iflag & VI_CLEAN) != 0) { 778 1.5.2.2 rmind /* 779 1.5.2.2 rmind * It's clean so destroy it. It isn't referenced 780 1.5.2.2 rmind * anywhere since it has been reclaimed. 781 1.5.2.2 rmind */ 782 1.5.2.2 rmind KASSERT(vp->v_holdcnt == 0); 783 1.5.2.2 rmind KASSERT(vp->v_writecount == 0); 784 1.5.2.2 rmind mutex_exit(vp->v_interlock); 785 1.5.2.2 rmind vfs_insmntque(vp, NULL); 786 1.5.2.2 rmind if (vp->v_type == VBLK || vp->v_type == VCHR) { 787 1.5.2.2 rmind spec_node_destroy(vp); 788 1.5.2.2 rmind } 789 1.5.2.2 rmind vnfree(vp); 790 1.5.2.2 rmind } else { 791 1.5.2.2 rmind /* 792 1.5.2.2 rmind * Otherwise, put it back onto the freelist. It 793 1.5.2.2 rmind * can't be destroyed while still associated with 794 1.5.2.2 rmind * a file system. 795 1.5.2.2 rmind */ 796 1.5.2.2 rmind mutex_enter(&vnode_free_list_lock); 797 1.5.2.2 rmind if (vp->v_holdcnt > 0) { 798 1.5.2.2 rmind vp->v_freelisthd = &vnode_hold_list; 799 1.5.2.2 rmind } else { 800 1.5.2.2 rmind vp->v_freelisthd = &vnode_free_list; 801 1.5.2.2 rmind } 802 1.5.2.2 rmind TAILQ_INSERT_TAIL(vp->v_freelisthd, vp, v_freelist); 803 1.5.2.2 rmind mutex_exit(&vnode_free_list_lock); 804 1.5.2.2 rmind mutex_exit(vp->v_interlock); 805 1.5.2.2 rmind } 806 1.5.2.2 rmind } 807 1.5.2.2 rmind 808 1.5.2.2 rmind void 809 1.5.2.2 rmind vrele(vnode_t *vp) 810 1.5.2.2 rmind { 811 1.5.2.2 rmind 812 1.5.2.2 rmind KASSERT((vp->v_iflag & VI_MARKER) == 0); 813 1.5.2.2 rmind 814 1.5.2.2 rmind if ((vp->v_iflag & VI_INACTNOW) == 0 && vtryrele(vp)) { 815 1.5.2.2 rmind return; 816 1.5.2.2 rmind } 817 1.5.2.2 rmind mutex_enter(vp->v_interlock); 818 1.5.2.2 rmind vrelel(vp, 0); 819 1.5.2.2 rmind } 820 1.5.2.2 rmind 821 1.5.2.2 rmind /* 822 1.5.2.2 rmind * Asynchronous vnode release, vnode is released in different context. 823 1.5.2.2 rmind */ 824 1.5.2.2 rmind void 825 1.5.2.2 rmind vrele_async(vnode_t *vp) 826 1.5.2.2 rmind { 827 1.5.2.2 rmind 828 1.5.2.2 rmind KASSERT((vp->v_iflag & VI_MARKER) == 0); 829 1.5.2.2 rmind 830 1.5.2.2 rmind if ((vp->v_iflag & VI_INACTNOW) == 0 && vtryrele(vp)) { 831 1.5.2.2 rmind return; 832 1.5.2.2 rmind } 833 1.5.2.2 rmind mutex_enter(vp->v_interlock); 834 1.5.2.2 rmind vrelel(vp, VRELEL_ASYNC_RELE); 835 1.5.2.2 rmind } 836 1.5.2.2 rmind 837 1.5.2.2 rmind static void 838 1.5.2.2 rmind vrele_thread(void *cookie) 839 1.5.2.2 rmind { 840 1.5.2.2 rmind vnode_t *vp; 841 1.5.2.2 rmind 842 1.5.2.2 rmind for (;;) { 843 1.5.2.2 rmind mutex_enter(&vrele_lock); 844 1.5.2.2 rmind while (TAILQ_EMPTY(&vrele_list)) { 845 1.5.2.2 rmind vrele_gen++; 846 1.5.2.2 rmind cv_broadcast(&vrele_cv); 847 1.5.2.2 rmind cv_timedwait(&vrele_cv, &vrele_lock, hz); 848 1.5.2.2 rmind } 849 1.5.2.2 rmind vp = TAILQ_FIRST(&vrele_list); 850 1.5.2.2 rmind TAILQ_REMOVE(&vrele_list, vp, v_freelist); 851 1.5.2.2 rmind vrele_pending--; 852 1.5.2.2 rmind mutex_exit(&vrele_lock); 853 1.5.2.2 rmind 854 1.5.2.2 rmind /* 855 1.5.2.2 rmind * If not the last reference, then ignore the vnode 856 1.5.2.2 rmind * and look for more work. 857 1.5.2.2 rmind */ 858 1.5.2.2 rmind mutex_enter(vp->v_interlock); 859 1.5.2.2 rmind KASSERT((vp->v_iflag & VI_INACTPEND) != 0); 860 1.5.2.2 rmind vp->v_iflag &= ~VI_INACTPEND; 861 1.5.2.2 rmind vrelel(vp, 0); 862 1.5.2.2 rmind } 863 1.5.2.2 rmind } 864 1.5.2.2 rmind 865 1.5.2.2 rmind void 866 1.5.2.2 rmind vrele_flush(void) 867 1.5.2.2 rmind { 868 1.5.2.2 rmind int gen; 869 1.5.2.2 rmind 870 1.5.2.2 rmind mutex_enter(&vrele_lock); 871 1.5.2.2 rmind gen = vrele_gen; 872 1.5.2.2 rmind while (vrele_pending && gen == vrele_gen) { 873 1.5.2.2 rmind cv_broadcast(&vrele_cv); 874 1.5.2.2 rmind cv_wait(&vrele_cv, &vrele_lock); 875 1.5.2.2 rmind } 876 1.5.2.2 rmind mutex_exit(&vrele_lock); 877 1.5.2.2 rmind } 878 1.5.2.2 rmind 879 1.5.2.2 rmind /* 880 1.5.2.2 rmind * Vnode reference, where a reference is already held by some other 881 1.5.2.2 rmind * object (for example, a file structure). 882 1.5.2.2 rmind */ 883 1.5.2.2 rmind void 884 1.5.2.2 rmind vref(vnode_t *vp) 885 1.5.2.2 rmind { 886 1.5.2.2 rmind 887 1.5.2.2 rmind KASSERT((vp->v_iflag & VI_MARKER) == 0); 888 1.5.2.2 rmind KASSERT(vp->v_usecount != 0); 889 1.5.2.2 rmind 890 1.5.2.2 rmind atomic_inc_uint(&vp->v_usecount); 891 1.5.2.2 rmind } 892 1.5.2.2 rmind 893 1.5.2.2 rmind /* 894 1.5.2.2 rmind * Page or buffer structure gets a reference. 895 1.5.2.2 rmind * Called with v_interlock held. 896 1.5.2.2 rmind */ 897 1.5.2.2 rmind void 898 1.5.2.2 rmind vholdl(vnode_t *vp) 899 1.5.2.2 rmind { 900 1.5.2.2 rmind 901 1.5.2.2 rmind KASSERT(mutex_owned(vp->v_interlock)); 902 1.5.2.2 rmind KASSERT((vp->v_iflag & VI_MARKER) == 0); 903 1.5.2.2 rmind 904 1.5.2.2 rmind if (vp->v_holdcnt++ == 0 && vp->v_usecount == 0) { 905 1.5.2.2 rmind mutex_enter(&vnode_free_list_lock); 906 1.5.2.2 rmind KASSERT(vp->v_freelisthd == &vnode_free_list); 907 1.5.2.2 rmind TAILQ_REMOVE(vp->v_freelisthd, vp, v_freelist); 908 1.5.2.2 rmind vp->v_freelisthd = &vnode_hold_list; 909 1.5.2.2 rmind TAILQ_INSERT_TAIL(vp->v_freelisthd, vp, v_freelist); 910 1.5.2.2 rmind mutex_exit(&vnode_free_list_lock); 911 1.5.2.2 rmind } 912 1.5.2.2 rmind } 913 1.5.2.2 rmind 914 1.5.2.2 rmind /* 915 1.5.2.2 rmind * Page or buffer structure frees a reference. 916 1.5.2.2 rmind * Called with v_interlock held. 917 1.5.2.2 rmind */ 918 1.5.2.2 rmind void 919 1.5.2.2 rmind holdrelel(vnode_t *vp) 920 1.5.2.2 rmind { 921 1.5.2.2 rmind 922 1.5.2.2 rmind KASSERT(mutex_owned(vp->v_interlock)); 923 1.5.2.2 rmind KASSERT((vp->v_iflag & VI_MARKER) == 0); 924 1.5.2.2 rmind 925 1.5.2.2 rmind if (vp->v_holdcnt <= 0) { 926 1.5.2.2 rmind vpanic(vp, "holdrelel: holdcnt vp %p"); 927 1.5.2.2 rmind } 928 1.5.2.2 rmind 929 1.5.2.2 rmind vp->v_holdcnt--; 930 1.5.2.2 rmind if (vp->v_holdcnt == 0 && vp->v_usecount == 0) { 931 1.5.2.2 rmind mutex_enter(&vnode_free_list_lock); 932 1.5.2.2 rmind KASSERT(vp->v_freelisthd == &vnode_hold_list); 933 1.5.2.2 rmind TAILQ_REMOVE(vp->v_freelisthd, vp, v_freelist); 934 1.5.2.2 rmind vp->v_freelisthd = &vnode_free_list; 935 1.5.2.2 rmind TAILQ_INSERT_TAIL(vp->v_freelisthd, vp, v_freelist); 936 1.5.2.2 rmind mutex_exit(&vnode_free_list_lock); 937 1.5.2.2 rmind } 938 1.5.2.2 rmind } 939 1.5.2.2 rmind 940 1.5.2.2 rmind /* 941 1.5.2.2 rmind * Disassociate the underlying file system from a vnode. 942 1.5.2.2 rmind * 943 1.5.2.2 rmind * Must be called with the interlock held, and will return with it held. 944 1.5.2.2 rmind */ 945 1.5.2.2 rmind void 946 1.5.2.2 rmind vclean(vnode_t *vp, int flags) 947 1.5.2.2 rmind { 948 1.5.2.2 rmind lwp_t *l = curlwp; 949 1.5.2.2 rmind bool recycle, active; 950 1.5.2.2 rmind int error; 951 1.5.2.2 rmind 952 1.5.2.2 rmind KASSERT(mutex_owned(vp->v_interlock)); 953 1.5.2.2 rmind KASSERT((vp->v_iflag & VI_MARKER) == 0); 954 1.5.2.2 rmind KASSERT(vp->v_usecount != 0); 955 1.5.2.2 rmind 956 1.5.2.2 rmind /* If cleaning is already in progress wait until done and return. */ 957 1.5.2.2 rmind if (vp->v_iflag & VI_XLOCK) { 958 1.5.2.2 rmind vwait(vp, VI_XLOCK); 959 1.5.2.2 rmind return; 960 1.5.2.2 rmind } 961 1.5.2.2 rmind 962 1.5.2.2 rmind /* If already clean, nothing to do. */ 963 1.5.2.2 rmind if ((vp->v_iflag & VI_CLEAN) != 0) { 964 1.5.2.2 rmind return; 965 1.5.2.2 rmind } 966 1.5.2.2 rmind 967 1.5.2.2 rmind /* 968 1.5.2.2 rmind * Prevent the vnode from being recycled or brought into use 969 1.5.2.2 rmind * while we clean it out. 970 1.5.2.2 rmind */ 971 1.5.2.2 rmind vp->v_iflag |= VI_XLOCK; 972 1.5.2.2 rmind if (vp->v_iflag & VI_EXECMAP) { 973 1.5.2.2 rmind atomic_add_int(&uvmexp.execpages, -vp->v_uobj.uo_npages); 974 1.5.2.2 rmind atomic_add_int(&uvmexp.filepages, vp->v_uobj.uo_npages); 975 1.5.2.2 rmind } 976 1.5.2.2 rmind vp->v_iflag &= ~(VI_TEXT|VI_EXECMAP); 977 1.5.2.2 rmind active = (vp->v_usecount & VC_MASK) > 1; 978 1.5.2.2 rmind 979 1.5.2.2 rmind /* XXXAD should not lock vnode under layer */ 980 1.5.2.2 rmind mutex_exit(vp->v_interlock); 981 1.5.2.2 rmind VOP_LOCK(vp, LK_EXCLUSIVE); 982 1.5.2.2 rmind 983 1.5.2.2 rmind /* 984 1.5.2.2 rmind * Clean out any cached data associated with the vnode. 985 1.5.2.2 rmind * If purging an active vnode, it must be closed and 986 1.5.2.2 rmind * deactivated before being reclaimed. Note that the 987 1.5.2.2 rmind * VOP_INACTIVE will unlock the vnode. 988 1.5.2.2 rmind */ 989 1.5.2.2 rmind if (flags & DOCLOSE) { 990 1.5.2.2 rmind error = vinvalbuf(vp, V_SAVE, NOCRED, l, 0, 0); 991 1.5.2.2 rmind if (error != 0) { 992 1.5.2.2 rmind /* XXX, fix vn_start_write's grab of mp and use that. */ 993 1.5.2.2 rmind 994 1.5.2.2 rmind if (wapbl_vphaswapbl(vp)) 995 1.5.2.2 rmind WAPBL_DISCARD(wapbl_vptomp(vp)); 996 1.5.2.2 rmind error = vinvalbuf(vp, 0, NOCRED, l, 0, 0); 997 1.5.2.2 rmind } 998 1.5.2.2 rmind KASSERT(error == 0); 999 1.5.2.2 rmind KASSERT((vp->v_iflag & VI_ONWORKLST) == 0); 1000 1.5.2.2 rmind if (active && (vp->v_type == VBLK || vp->v_type == VCHR)) { 1001 1.5.2.2 rmind spec_node_revoke(vp); 1002 1.5.2.2 rmind } 1003 1.5.2.2 rmind } 1004 1.5.2.2 rmind if (active) { 1005 1.5.2.2 rmind VOP_INACTIVE(vp, &recycle); 1006 1.5.2.2 rmind } else { 1007 1.5.2.2 rmind /* 1008 1.5.2.2 rmind * Any other processes trying to obtain this lock must first 1009 1.5.2.2 rmind * wait for VI_XLOCK to clear, then call the new lock operation. 1010 1.5.2.2 rmind */ 1011 1.5.2.2 rmind VOP_UNLOCK(vp); 1012 1.5.2.2 rmind } 1013 1.5.2.2 rmind 1014 1.5.2.2 rmind /* Disassociate the underlying file system from the vnode. */ 1015 1.5.2.2 rmind if (VOP_RECLAIM(vp)) { 1016 1.5.2.2 rmind vpanic(vp, "vclean: cannot reclaim"); 1017 1.5.2.2 rmind } 1018 1.5.2.2 rmind 1019 1.5.2.2 rmind KASSERT(vp->v_uobj.uo_npages == 0); 1020 1.5.2.2 rmind if (vp->v_type == VREG && vp->v_ractx != NULL) { 1021 1.5.2.2 rmind uvm_ra_freectx(vp->v_ractx); 1022 1.5.2.2 rmind vp->v_ractx = NULL; 1023 1.5.2.2 rmind } 1024 1.5.2.2 rmind cache_purge(vp); 1025 1.5.2.2 rmind 1026 1.5.2.2 rmind /* Done with purge, notify sleepers of the grim news. */ 1027 1.5.2.2 rmind mutex_enter(vp->v_interlock); 1028 1.5.2.2 rmind vp->v_op = dead_vnodeop_p; 1029 1.5.2.2 rmind vp->v_tag = VT_NON; 1030 1.5.2.2 rmind KNOTE(&vp->v_klist, NOTE_REVOKE); 1031 1.5.2.2 rmind vp->v_iflag &= ~VI_XLOCK; 1032 1.5.2.2 rmind vp->v_vflag &= ~VV_LOCKSWORK; 1033 1.5.2.2 rmind if ((flags & DOCLOSE) != 0) { 1034 1.5.2.2 rmind vp->v_iflag |= VI_CLEAN; 1035 1.5.2.2 rmind } 1036 1.5.2.2 rmind cv_broadcast(&vp->v_cv); 1037 1.5.2.2 rmind 1038 1.5.2.2 rmind KASSERT((vp->v_iflag & VI_ONWORKLST) == 0); 1039 1.5.2.2 rmind } 1040 1.5.2.2 rmind 1041 1.5.2.2 rmind /* 1042 1.5.2.2 rmind * Recycle an unused vnode to the front of the free list. 1043 1.5.2.2 rmind * Release the passed interlock if the vnode will be recycled. 1044 1.5.2.2 rmind */ 1045 1.5.2.2 rmind int 1046 1.5.2.2 rmind vrecycle(vnode_t *vp, kmutex_t *inter_lkp, struct lwp *l) 1047 1.5.2.2 rmind { 1048 1.5.2.2 rmind 1049 1.5.2.2 rmind KASSERT((vp->v_iflag & VI_MARKER) == 0); 1050 1.5.2.2 rmind 1051 1.5.2.2 rmind mutex_enter(vp->v_interlock); 1052 1.5.2.2 rmind if (vp->v_usecount != 0) { 1053 1.5.2.2 rmind mutex_exit(vp->v_interlock); 1054 1.5.2.2 rmind return 0; 1055 1.5.2.2 rmind } 1056 1.5.2.2 rmind if (inter_lkp) { 1057 1.5.2.2 rmind mutex_exit(inter_lkp); 1058 1.5.2.2 rmind } 1059 1.5.2.2 rmind vremfree(vp); 1060 1.5.2.2 rmind vp->v_usecount = 1; 1061 1.5.2.2 rmind vclean(vp, DOCLOSE); 1062 1.5.2.2 rmind vrelel(vp, 0); 1063 1.5.2.2 rmind return 1; 1064 1.5.2.2 rmind } 1065 1.5.2.2 rmind 1066 1.5.2.2 rmind /* 1067 1.5.2.2 rmind * Eliminate all activity associated with the requested vnode 1068 1.5.2.2 rmind * and with all vnodes aliased to the requested vnode. 1069 1.5.2.2 rmind */ 1070 1.5.2.2 rmind void 1071 1.5.2.2 rmind vrevoke(vnode_t *vp) 1072 1.5.2.2 rmind { 1073 1.5.2.2 rmind vnode_t *vq, **vpp; 1074 1.5.2.2 rmind enum vtype type; 1075 1.5.2.2 rmind dev_t dev; 1076 1.5.2.2 rmind 1077 1.5.2.2 rmind KASSERT(vp->v_usecount > 0); 1078 1.5.2.2 rmind 1079 1.5.2.2 rmind mutex_enter(vp->v_interlock); 1080 1.5.2.2 rmind if ((vp->v_iflag & VI_CLEAN) != 0) { 1081 1.5.2.2 rmind mutex_exit(vp->v_interlock); 1082 1.5.2.2 rmind return; 1083 1.5.2.2 rmind } else if (vp->v_type != VBLK && vp->v_type != VCHR) { 1084 1.5.2.2 rmind atomic_inc_uint(&vp->v_usecount); 1085 1.5.2.2 rmind vclean(vp, DOCLOSE); 1086 1.5.2.2 rmind vrelel(vp, 0); 1087 1.5.2.2 rmind return; 1088 1.5.2.2 rmind } else { 1089 1.5.2.2 rmind dev = vp->v_rdev; 1090 1.5.2.2 rmind type = vp->v_type; 1091 1.5.2.2 rmind mutex_exit(vp->v_interlock); 1092 1.5.2.2 rmind } 1093 1.5.2.2 rmind 1094 1.5.2.2 rmind vpp = &specfs_hash[SPECHASH(dev)]; 1095 1.5.2.2 rmind mutex_enter(&device_lock); 1096 1.5.2.2 rmind for (vq = *vpp; vq != NULL;) { 1097 1.5.2.2 rmind /* If clean or being cleaned, then ignore it. */ 1098 1.5.2.2 rmind mutex_enter(vq->v_interlock); 1099 1.5.2.2 rmind if ((vq->v_iflag & (VI_CLEAN | VI_XLOCK)) != 0 || 1100 1.5.2.2 rmind vq->v_rdev != dev || vq->v_type != type) { 1101 1.5.2.2 rmind mutex_exit(vq->v_interlock); 1102 1.5.2.2 rmind vq = vq->v_specnext; 1103 1.5.2.2 rmind continue; 1104 1.5.2.2 rmind } 1105 1.5.2.2 rmind mutex_exit(&device_lock); 1106 1.5.2.2 rmind if (vq->v_usecount == 0) { 1107 1.5.2.2 rmind vremfree(vq); 1108 1.5.2.2 rmind vq->v_usecount = 1; 1109 1.5.2.2 rmind } else { 1110 1.5.2.2 rmind atomic_inc_uint(&vq->v_usecount); 1111 1.5.2.2 rmind } 1112 1.5.2.2 rmind vclean(vq, DOCLOSE); 1113 1.5.2.2 rmind vrelel(vq, 0); 1114 1.5.2.2 rmind mutex_enter(&device_lock); 1115 1.5.2.2 rmind vq = *vpp; 1116 1.5.2.2 rmind } 1117 1.5.2.2 rmind mutex_exit(&device_lock); 1118 1.5.2.2 rmind } 1119 1.5.2.2 rmind 1120 1.5.2.2 rmind /* 1121 1.5.2.2 rmind * Eliminate all activity associated with a vnode in preparation for 1122 1.5.2.2 rmind * reuse. Drops a reference from the vnode. 1123 1.5.2.2 rmind */ 1124 1.5.2.2 rmind void 1125 1.5.2.2 rmind vgone(vnode_t *vp) 1126 1.5.2.2 rmind { 1127 1.5.2.2 rmind 1128 1.5.2.2 rmind mutex_enter(vp->v_interlock); 1129 1.5.2.2 rmind vclean(vp, DOCLOSE); 1130 1.5.2.2 rmind vrelel(vp, 0); 1131 1.5.2.2 rmind } 1132 1.5.2.2 rmind 1133 1.5.2.2 rmind /* 1134 1.5.2.2 rmind * Update outstanding I/O count and do wakeup if requested. 1135 1.5.2.2 rmind */ 1136 1.5.2.2 rmind void 1137 1.5.2.2 rmind vwakeup(struct buf *bp) 1138 1.5.2.2 rmind { 1139 1.5.2.2 rmind vnode_t *vp; 1140 1.5.2.2 rmind 1141 1.5.2.2 rmind if ((vp = bp->b_vp) == NULL) 1142 1.5.2.2 rmind return; 1143 1.5.2.2 rmind 1144 1.5.2.2 rmind KASSERT(bp->b_objlock == vp->v_interlock); 1145 1.5.2.2 rmind KASSERT(mutex_owned(bp->b_objlock)); 1146 1.5.2.2 rmind 1147 1.5.2.2 rmind if (--vp->v_numoutput < 0) 1148 1.5.2.2 rmind panic("vwakeup: neg numoutput, vp %p", vp); 1149 1.5.2.2 rmind if (vp->v_numoutput == 0) 1150 1.5.2.2 rmind cv_broadcast(&vp->v_cv); 1151 1.5.2.2 rmind } 1152 1.5.2.2 rmind 1153 1.5.2.2 rmind /* 1154 1.5.2.2 rmind * Wait for a vnode (typically with VI_XLOCK set) to be cleaned or 1155 1.5.2.2 rmind * recycled. 1156 1.5.2.2 rmind */ 1157 1.5.2.2 rmind void 1158 1.5.2.2 rmind vwait(vnode_t *vp, int flags) 1159 1.5.2.2 rmind { 1160 1.5.2.2 rmind 1161 1.5.2.2 rmind KASSERT(mutex_owned(vp->v_interlock)); 1162 1.5.2.2 rmind KASSERT(vp->v_usecount != 0); 1163 1.5.2.2 rmind 1164 1.5.2.2 rmind while ((vp->v_iflag & flags) != 0) 1165 1.5.2.2 rmind cv_wait(&vp->v_cv, vp->v_interlock); 1166 1.5.2.2 rmind } 1167 1.5.2.2 rmind 1168 1.5.2.2 rmind int 1169 1.5.2.2 rmind vfs_drainvnodes(long target) 1170 1.5.2.2 rmind { 1171 1.5.2.2 rmind 1172 1.5.2.2 rmind while (numvnodes > target) { 1173 1.5.2.2 rmind vnode_t *vp; 1174 1.5.2.2 rmind 1175 1.5.2.2 rmind mutex_enter(&vnode_free_list_lock); 1176 1.5.2.2 rmind vp = getcleanvnode(); 1177 1.5.2.2 rmind if (vp == NULL) { 1178 1.5.2.2 rmind return EBUSY; 1179 1.5.2.2 rmind } 1180 1.5.2.2 rmind ungetnewvnode(vp); 1181 1.5.2.2 rmind } 1182 1.5.2.2 rmind return 0; 1183 1.5.2.2 rmind } 1184 1.5.2.2 rmind 1185 1.5.2.2 rmind void 1186 1.5.2.2 rmind vpanic(vnode_t *vp, const char *msg) 1187 1.5.2.2 rmind { 1188 1.5.2.2 rmind #ifdef DIAGNOSTIC 1189 1.5.2.2 rmind 1190 1.5.2.2 rmind vprint(NULL, vp); 1191 1.5.2.2 rmind panic("%s\n", msg); 1192 1.5.2.2 rmind #endif 1193 1.5.2.2 rmind } 1194
Indexes created Sun Sep 21 20:09:37 GMT 2025