1 /* 2 * Copyright (c) 2003,2004 The DragonFly Project. All rights reserved. 3 * 4 * This code is derived from software contributed to The DragonFly Project 5 * by Matthew Dillon <dillon@backplane.com> 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 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 15 * the documentation and/or other materials provided with the 16 * distribution. 17 * 3. Neither the name of The DragonFly Project nor the names of its 18 * contributors may be used to endorse or promote products derived 19 * from this software without specific, prior written permission. 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 22 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 23 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 24 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 25 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 26 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING, 27 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 28 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 29 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 30 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 31 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * 35 * Copyright (c) 1989, 1993 36 * The Regents of the University of California. All rights reserved. 37 * 38 * This code is derived from software contributed 39 * to Berkeley by John Heidemann of the UCLA Ficus project. 40 * 41 * Source: * @(#)i405_init.c 2.10 92/04/27 UCLA Ficus project 42 * 43 * Redistribution and use in source and binary forms, with or without 44 * modification, are permitted provided that the following conditions 45 * are met: 46 * 1. Redistributions of source code must retain the above copyright 47 * notice, this list of conditions and the following disclaimer. 48 * 2. Redistributions in binary form must reproduce the above copyright 49 * notice, this list of conditions and the following disclaimer in the 50 * documentation and/or other materials provided with the distribution. 51 * 3. All advertising materials mentioning features or use of this software 52 * must display the following acknowledgement: 53 * This product includes software developed by the University of 54 * California, Berkeley and its contributors. 55 * 4. Neither the name of the University nor the names of its contributors 56 * may be used to endorse or promote products derived from this software 57 * without specific prior written permission. 58 * 59 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 60 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 61 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 62 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 63 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 64 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 65 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 66 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 67 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 68 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 69 * SUCH DAMAGE. 70 * 71 * @(#)vfs_init.c 8.3 (Berkeley) 1/4/94 72 * $FreeBSD: src/sys/kern/vfs_init.c,v 1.59 2002/04/30 18:44:32 dillon Exp $ 73 * $DragonFly: src/sys/kern/vfs_init.c,v 1.10 2005/09/17 07:43:00 dillon Exp $ 74 */ 75 /* 76 * Manage vnode VOP operations vectors 77 */ 78 #include <sys/param.h> 79 #include <sys/systm.h> 80 #include <sys/kernel.h> 81 #include <sys/mount.h> 82 #include <sys/sysctl.h> 83 #include <sys/vnode.h> 84 #include <sys/malloc.h> 85 #include <vm/vm_zone.h> 86 87 static MALLOC_DEFINE(M_VNODEOP, "vnodeops", "vnode operations vectors"); 88 89 /* 90 * Zone for namei 91 */ 92 struct vm_zone *namei_zone; 93 94 /* 95 * vfs_init() will set maxvfsconf 96 * to the highest defined type number. 97 */ 98 int maxvfsconf; 99 struct vfsconf *vfsconf; 100 101 static TAILQ_HEAD(, vnodeopv_node) vnodeopv_list; 102 static void vfs_recalc_vnodeops(void); 103 104 /* 105 * Add a vnode operations (vnops) vector to the global list. 106 */ 107 void 108 vfs_add_vnodeops_sysinit(const void *data) 109 { 110 const struct vnodeopv_desc *vdesc = data; 111 112 vfs_add_vnodeops(NULL, vdesc->opv_desc_vector, 113 vdesc->opv_desc_ops, vdesc->opv_flags); 114 } 115 116 /* 117 * Unlink previously added vnode operations vector. 118 */ 119 void 120 vfs_rm_vnodeops_sysinit(const void *data) 121 { 122 const struct vnodeopv_desc *vdesc = data; 123 124 vfs_rm_vnodeops(vdesc->opv_desc_vector); 125 } 126 127 void 128 vfs_add_vnodeops(struct mount *mp, struct vop_ops **vops_pp, 129 struct vnodeopv_entry_desc *descs, int flags) 130 { 131 struct vnodeopv_node *node; 132 struct vop_ops *ops; 133 134 node = malloc(sizeof(*node), M_VNODEOP, M_ZERO|M_WAITOK); 135 if ((ops = *vops_pp) == NULL) { 136 ops = malloc(sizeof(struct vop_ops), 137 M_VNODEOP, M_ZERO|M_WAITOK); 138 *vops_pp = ops; 139 } 140 node->ops = ops; 141 node->descs = descs; 142 ops->vv_mount = mp; 143 ops->vv_flags |= flags; 144 145 /* 146 * Journal and coherency ops inherit normal ops flags 147 */ 148 if (vops_pp == &mp->mnt_vn_coherency_ops && mp->mnt_vn_norm_ops) 149 ops->vv_flags |= mp->mnt_vn_norm_ops->vv_flags; 150 if (vops_pp == &mp->mnt_vn_journal_ops && mp->mnt_vn_norm_ops) 151 ops->vv_flags |= mp->mnt_vn_norm_ops->vv_flags; 152 153 ++ops->vv_refs; 154 TAILQ_INSERT_TAIL(&vnodeopv_list, node, entry); 155 156 vfs_recalc_vnodeops(); 157 158 if (mp) { 159 if (mp->mnt_vn_coherency_ops) 160 mp->mnt_vn_use_ops = mp->mnt_vn_coherency_ops; 161 else if (mp->mnt_vn_journal_ops) 162 mp->mnt_vn_use_ops = mp->mnt_vn_journal_ops; 163 else 164 mp->mnt_vn_use_ops = mp->mnt_vn_norm_ops; 165 } 166 } 167 168 void 169 vfs_rm_vnodeops(struct vop_ops **vops_pp) 170 { 171 struct vop_ops *ops = *vops_pp; 172 struct vnodeopv_node *node; 173 struct mount *mp; 174 175 if (ops == NULL) 176 return; 177 178 TAILQ_FOREACH(node, &vnodeopv_list, entry) { 179 if (node->ops == ops) 180 break; 181 } 182 if (node == NULL) { 183 printf("vfs_rm_vnodeops: unable to find ops: %p\n", ops); 184 return; 185 } 186 TAILQ_REMOVE(&vnodeopv_list, node, entry); 187 free(node, M_VNODEOP); 188 KKASSERT(ops != NULL && ops->vv_refs > 0); 189 if (--ops->vv_refs == 0) { 190 *vops_pp = NULL; 191 if ((mp = ops->vv_mount) != NULL) { 192 if (mp->mnt_vn_coherency_ops) 193 mp->mnt_vn_use_ops = mp->mnt_vn_coherency_ops; 194 else if (mp->mnt_vn_journal_ops) 195 mp->mnt_vn_use_ops = mp->mnt_vn_journal_ops; 196 else 197 mp->mnt_vn_use_ops = mp->mnt_vn_norm_ops; 198 } 199 free(ops, M_VNODEOP); 200 } 201 vfs_recalc_vnodeops(); 202 } 203 204 /* 205 * Recalculate VFS operations vectors 206 */ 207 static void 208 vfs_recalc_vnodeops(void) 209 { 210 struct vnodeopv_node *node; 211 struct vnodeopv_entry_desc *desc; 212 struct vop_ops *ops; 213 struct vop_ops *vnew; 214 int off; 215 216 /* 217 * Because vop_ops may be active we can't just blow them away, we 218 * have to generate new vop_ops and then copy them into the running 219 * vop_ops. Any missing entries will be assigned to the default 220 * entry. If the default entry itself is missing it will be assigned 221 * to vop_eopnotsupp. 222 */ 223 TAILQ_FOREACH(node, &vnodeopv_list, entry) { 224 ops = node->ops; 225 if ((vnew = ops->vv_new) == NULL) { 226 vnew = malloc(sizeof(struct vop_ops), 227 M_VNODEOP, M_ZERO|M_WAITOK); 228 ops->vv_new = vnew; 229 vnew->vop_default = vop_eopnotsupp; 230 } 231 for (desc = node->descs; desc->opve_op; ++desc) { 232 off = desc->opve_op->vdesc_offset; 233 *(void **)((char *)vnew + off) = desc->opve_func; 234 } 235 for (off = __offsetof(struct vop_ops, vop_ops_first_field); 236 off <= __offsetof(struct vop_ops, vop_ops_last_field); 237 off += sizeof(void **) 238 ) { 239 if (*(void **)((char *)vnew + off) == NULL) 240 *(void **)((char *)vnew + off) = vnew->vop_default; 241 } 242 } 243 244 /* 245 * Copy the temporary ops into the running configuration and then 246 * delete them. 247 */ 248 TAILQ_FOREACH(node, &vnodeopv_list, entry) { 249 ops = node->ops; 250 if ((vnew = ops->vv_new) == NULL) 251 continue; 252 for (off = __offsetof(struct vop_ops, vop_ops_first_field); 253 off <= __offsetof(struct vop_ops, vop_ops_last_field); 254 off += sizeof(void **) 255 ) { 256 *(void **)((char *)ops + off) = 257 *(void **)((char *)vnew + off); 258 } 259 ops->vv_new = NULL; 260 free(vnew, M_VNODEOP); 261 } 262 } 263 264 /* 265 * Routines having to do with the management of the vnode table. 266 */ 267 struct vattr va_null; 268 269 /* 270 * Initialize the vnode structures and initialize each file system type. 271 */ 272 /* ARGSUSED*/ 273 static void 274 vfsinit(void *dummy) 275 { 276 TAILQ_INIT(&vnodeopv_list); 277 namei_zone = zinit("NAMEI", MAXPATHLEN, 0, 0, 2); 278 279 /* 280 * Initialize the vnode table 281 */ 282 vfs_subr_init(); 283 vfs_mount_init(); 284 vfs_lock_init(); 285 vfs_sync_init(); 286 /* 287 * Initialize the vnode name cache 288 */ 289 nchinit(); 290 /* 291 * Initialize each file system type. 292 * Vfs type numbers must be distinct from VFS_GENERIC (and VFS_VFSCONF). 293 */ 294 vattr_null(&va_null); 295 maxvfsconf = VFS_GENERIC + 1; 296 } 297 SYSINIT(vfs, SI_SUB_VFS, SI_ORDER_FIRST, vfsinit, NULL) 298 299 /* 300 * Register a VFS. 301 * 302 * After doing general initialisation, this function will 303 * call the filesystem specific initialisation vector op, 304 * i.e. vfsops->vfs_init(). 305 */ 306 int 307 vfs_register(struct vfsconf *vfc) 308 { 309 struct sysctl_oid *oidp; 310 struct vfsconf *vfsp; 311 struct vfsops *vfsops = NULL; 312 313 vfsp = NULL; 314 if (vfsconf) 315 for (vfsp = vfsconf; vfsp->vfc_next; vfsp = vfsp->vfc_next) 316 if (strcmp(vfc->vfc_name, vfsp->vfc_name) == 0) 317 return EEXIST; 318 319 vfc->vfc_typenum = maxvfsconf++; 320 if (vfsp) 321 vfsp->vfc_next = vfc; 322 else 323 vfsconf = vfc; 324 vfc->vfc_next = NULL; 325 326 /* 327 * If this filesystem has a sysctl node under vfs 328 * (i.e. vfs.xxfs), then change the oid number of that node to 329 * match the filesystem's type number. This allows user code 330 * which uses the type number to read sysctl variables defined 331 * by the filesystem to continue working. Since the oids are 332 * in a sorted list, we need to make sure the order is 333 * preserved by re-registering the oid after modifying its 334 * number. 335 */ 336 SLIST_FOREACH(oidp, &sysctl__vfs_children, oid_link) 337 if (strcmp(oidp->oid_name, vfc->vfc_name) == 0) { 338 sysctl_unregister_oid(oidp); 339 oidp->oid_number = vfc->vfc_typenum; 340 sysctl_register_oid(oidp); 341 } 342 343 /* 344 * Initialise unused fields in the file system's vfsops vector. 345 * 346 * NOTE the file system should provide the mount and unmount ops 347 * at the least. In order for unmount to succeed, we also need 348 * the file system to provide us with vfsops->vfs_root otherwise 349 * the unmount(2) operation will not succeed. 350 */ 351 vfsops = vfc->vfc_vfsops; 352 KKASSERT(vfc->vfc_vfsops != NULL); 353 KKASSERT(vfsops->vfs_mount != NULL); 354 KKASSERT(vfsops->vfs_root != NULL); 355 KKASSERT(vfsops->vfs_unmount != NULL); 356 357 if (vfsops->vfs_root == NULL) { 358 /* return file system's root vnode */ 359 vfsops->vfs_root = vfs_stdroot; 360 } 361 if (vfsops->vfs_start == NULL) { 362 /* 363 * Make file system operational before first use. This 364 * routine is called at mount-time for initialising MFS, 365 * not used by other file systems. 366 */ 367 vfsops->vfs_start = vfs_stdstart; 368 } 369 if (vfsops->vfs_quotactl == NULL) { 370 /* quota control */ 371 vfsops->vfs_quotactl = vfs_stdquotactl; 372 } 373 if (vfsops->vfs_statfs == NULL) { 374 /* return file system's status */ 375 vfsops->vfs_statfs = vfs_stdstatfs; 376 } 377 if (vfsops->vfs_sync == NULL) { 378 /* 379 * Flush dirty buffers. File systems can use vfs_stdsync() 380 * by explicitly setting it in the vfsops->vfs_sync vector 381 * entry. 382 */ 383 vfsops->vfs_sync = vfs_stdnosync; 384 } 385 if (vfsops->vfs_vget == NULL) { 386 /* convert an inode number to a vnode */ 387 vfsops->vfs_vget = vfs_stdvget; 388 } 389 if (vfsops->vfs_fhtovp == NULL) { 390 /* turn an NFS file handle into a vnode */ 391 vfsops->vfs_fhtovp = vfs_stdfhtovp; 392 } 393 if (vfsops->vfs_checkexp == NULL) { 394 /* check if file system is exported */ 395 vfsops->vfs_checkexp = vfs_stdcheckexp; 396 } 397 if (vfsops->vfs_vptofh == NULL) { 398 /* turn a vnode into an NFS file handle */ 399 vfsops->vfs_vptofh = vfs_stdvptofh; 400 } 401 if (vfsops->vfs_init == NULL) { 402 /* file system specific initialisation */ 403 vfsops->vfs_init = vfs_stdinit; 404 } 405 if (vfsops->vfs_uninit == NULL) { 406 /* file system specific uninitialisation */ 407 vfsops->vfs_uninit = vfs_stduninit; 408 } 409 if (vfsops->vfs_extattrctl == NULL) { 410 /* extended attribute control */ 411 vfsops->vfs_extattrctl = vfs_stdextattrctl; 412 } 413 414 /* 415 * Call init function for this VFS... 416 */ 417 (*(vfc->vfc_vfsops->vfs_init))(vfc); 418 419 return 0; 420 } 421 422 423 /* 424 * Remove previously registered VFS. 425 * 426 * After doing general de-registration like removing sysctl 427 * nodes etc, it will call the filesystem specific vector 428 * op, i.e. vfsops->vfs_uninit(). 429 * 430 */ 431 int 432 vfs_unregister(struct vfsconf *vfc) 433 { 434 struct vfsconf *vfsp, *prev_vfsp; 435 int error, i, maxtypenum; 436 437 i = vfc->vfc_typenum; 438 439 prev_vfsp = NULL; 440 for (vfsp = vfsconf; vfsp; 441 prev_vfsp = vfsp, vfsp = vfsp->vfc_next) { 442 if (!strcmp(vfc->vfc_name, vfsp->vfc_name)) 443 break; 444 } 445 if (vfsp == NULL) 446 return EINVAL; 447 if (vfsp->vfc_refcount) 448 return EBUSY; 449 if (vfc->vfc_vfsops->vfs_uninit != NULL) { 450 error = (*vfc->vfc_vfsops->vfs_uninit)(vfsp); 451 if (error) 452 return (error); 453 } 454 if (prev_vfsp) 455 prev_vfsp->vfc_next = vfsp->vfc_next; 456 else 457 vfsconf = vfsp->vfc_next; 458 maxtypenum = VFS_GENERIC; 459 for (vfsp = vfsconf; vfsp != NULL; vfsp = vfsp->vfc_next) 460 if (maxtypenum < vfsp->vfc_typenum) 461 maxtypenum = vfsp->vfc_typenum; 462 maxvfsconf = maxtypenum + 1; 463 return 0; 464 } 465 466 int 467 vfs_modevent(module_t mod, int type, void *data) 468 { 469 struct vfsconf *vfc; 470 int error = 0; 471 472 vfc = (struct vfsconf *)data; 473 474 switch (type) { 475 case MOD_LOAD: 476 if (vfc) 477 error = vfs_register(vfc); 478 break; 479 480 case MOD_UNLOAD: 481 if (vfc) 482 error = vfs_unregister(vfc); 483 break; 484 default: /* including MOD_SHUTDOWN */ 485 break; 486 } 487 return (error); 488 } 489