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 1.7 2004/10/12 19:20:46 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(vdesc->opv_desc_vector, vdesc->opv_desc_ops); 113 } 114 115 /* 116 * Unlink previously added vnode operations vector. 117 */ 118 void 119 vfs_rm_vnodeops_sysinit(const void *data) 120 { 121 const struct vnodeopv_desc *vdesc = data; 122 123 vfs_rm_vnodeops(vdesc->opv_desc_vector); 124 } 125 126 void 127 vfs_add_vnodeops(struct vop_ops **vops_pp, struct vnodeopv_entry_desc *descs) 128 { 129 struct vnodeopv_node *node; 130 struct vop_ops *ops; 131 132 node = malloc(sizeof(*node), M_VNODEOP, M_ZERO|M_WAITOK); 133 if ((ops = *vops_pp) == NULL) { 134 ops = malloc(sizeof(struct vop_ops), 135 M_VNODEOP, M_ZERO|M_WAITOK); 136 *vops_pp = ops; 137 } 138 node->ops = ops; 139 node->descs = descs; 140 ++ops->vv_refs; 141 TAILQ_INSERT_TAIL(&vnodeopv_list, node, entry); 142 vfs_recalc_vnodeops(); 143 } 144 145 void 146 vfs_rm_vnodeops(struct vop_ops **vops_pp) 147 { 148 struct vop_ops *ops = *vops_pp; 149 struct vnodeopv_node *node; 150 151 if (ops == NULL) 152 return; 153 154 TAILQ_FOREACH(node, &vnodeopv_list, entry) { 155 if (node->ops == ops) 156 break; 157 } 158 if (node == NULL) { 159 printf("vfs_rm_vnodeops: unable to find ops: %p\n", ops); 160 return; 161 } 162 TAILQ_REMOVE(&vnodeopv_list, node, entry); 163 free(node, M_VNODEOP); 164 KKASSERT(ops != NULL && ops->vv_refs > 0); 165 if (--ops->vv_refs == 0) { 166 *vops_pp = NULL; 167 free(ops, M_VNODEOP); 168 } 169 vfs_recalc_vnodeops(); 170 } 171 172 /* 173 * Recalculate VFS operations vectors 174 */ 175 static void 176 vfs_recalc_vnodeops(void) 177 { 178 struct vnodeopv_node *node; 179 struct vnodeopv_entry_desc *desc; 180 struct vop_ops *ops; 181 struct vop_ops *vnew; 182 int off; 183 184 /* 185 * Because vop_ops may be active we can't just blow them away, we 186 * have to generate new vop_ops and then copy them into the running 187 * vop_ops. Any missing entries will be assigned to the default 188 * entry. If the default entry itself is missing it will be assigned 189 * to vop_eopnotsupp. 190 */ 191 TAILQ_FOREACH(node, &vnodeopv_list, entry) { 192 ops = node->ops; 193 if ((vnew = ops->vv_new) == NULL) { 194 vnew = malloc(sizeof(struct vop_ops), 195 M_VNODEOP, M_ZERO|M_WAITOK); 196 ops->vv_new = vnew; 197 vnew->vop_default = vop_eopnotsupp; 198 } 199 for (desc = node->descs; desc->opve_op; ++desc) { 200 off = desc->opve_op->vdesc_offset; 201 *(void **)((char *)vnew + off) = desc->opve_func; 202 } 203 for (off = __offsetof(struct vop_ops, vop_ops_first_field); 204 off <= __offsetof(struct vop_ops, vop_ops_last_field); 205 off += sizeof(void **) 206 ) { 207 if (*(void **)((char *)vnew + off) == NULL) 208 *(void **)((char *)vnew + off) = vnew->vop_default; 209 } 210 } 211 212 /* 213 * Copy the temporary ops into the running configuration and then 214 * delete them. 215 */ 216 TAILQ_FOREACH(node, &vnodeopv_list, entry) { 217 ops = node->ops; 218 if ((vnew = ops->vv_new) == NULL) 219 continue; 220 for (off = __offsetof(struct vop_ops, vop_ops_first_field); 221 off <= __offsetof(struct vop_ops, vop_ops_last_field); 222 off += sizeof(void **) 223 ) { 224 *(void **)((char *)ops + off) = 225 *(void **)((char *)vnew + off); 226 } 227 ops->vv_new = NULL; 228 free(vnew, M_VNODEOP); 229 } 230 } 231 232 /* 233 * Routines having to do with the management of the vnode table. 234 */ 235 struct vattr va_null; 236 237 /* 238 * Initialize the vnode structures and initialize each file system type. 239 */ 240 /* ARGSUSED*/ 241 static void 242 vfsinit(void *dummy) 243 { 244 TAILQ_INIT(&vnodeopv_list); 245 namei_zone = zinit("NAMEI", MAXPATHLEN, 0, 0, 2); 246 247 /* 248 * Initialize the vnode table 249 */ 250 vfs_subr_init(); 251 vfs_mount_init(); 252 vfs_lock_init(); 253 vfs_sync_init(); 254 /* 255 * Initialize the vnode name cache 256 */ 257 nchinit(); 258 /* 259 * Initialize each file system type. 260 * Vfs type numbers must be distinct from VFS_GENERIC (and VFS_VFSCONF). 261 */ 262 vattr_null(&va_null); 263 maxvfsconf = VFS_GENERIC + 1; 264 } 265 SYSINIT(vfs, SI_SUB_VFS, SI_ORDER_FIRST, vfsinit, NULL) 266 267 /* 268 * Register a VFS. 269 * 270 * After doing general initialisation, this function will 271 * call the filesystem specific initialisation vector op, 272 * i.e. vfsops->vfs_init(). 273 */ 274 int 275 vfs_register(struct vfsconf *vfc) 276 { 277 struct sysctl_oid *oidp; 278 struct vfsconf *vfsp; 279 280 vfsp = NULL; 281 if (vfsconf) 282 for (vfsp = vfsconf; vfsp->vfc_next; vfsp = vfsp->vfc_next) 283 if (strcmp(vfc->vfc_name, vfsp->vfc_name) == 0) 284 return EEXIST; 285 286 vfc->vfc_typenum = maxvfsconf++; 287 if (vfsp) 288 vfsp->vfc_next = vfc; 289 else 290 vfsconf = vfc; 291 vfc->vfc_next = NULL; 292 293 /* 294 * If this filesystem has a sysctl node under vfs 295 * (i.e. vfs.xxfs), then change the oid number of that node to 296 * match the filesystem's type number. This allows user code 297 * which uses the type number to read sysctl variables defined 298 * by the filesystem to continue working. Since the oids are 299 * in a sorted list, we need to make sure the order is 300 * preserved by re-registering the oid after modifying its 301 * number. 302 */ 303 SLIST_FOREACH(oidp, &sysctl__vfs_children, oid_link) 304 if (strcmp(oidp->oid_name, vfc->vfc_name) == 0) { 305 sysctl_unregister_oid(oidp); 306 oidp->oid_number = vfc->vfc_typenum; 307 sysctl_register_oid(oidp); 308 } 309 310 /* 311 * Call init function for this VFS... 312 */ 313 (*(vfc->vfc_vfsops->vfs_init))(vfc); 314 315 return 0; 316 } 317 318 319 /* 320 * Remove previously registered VFS. 321 * 322 * After doing general de-registration like removing sysctl 323 * nodes etc, it will call the filesystem specific vector 324 * op, i.e. vfsops->vfs_uninit(). 325 * 326 */ 327 int 328 vfs_unregister(struct vfsconf *vfc) 329 { 330 struct vfsconf *vfsp, *prev_vfsp; 331 int error, i, maxtypenum; 332 333 i = vfc->vfc_typenum; 334 335 prev_vfsp = NULL; 336 for (vfsp = vfsconf; vfsp; 337 prev_vfsp = vfsp, vfsp = vfsp->vfc_next) { 338 if (!strcmp(vfc->vfc_name, vfsp->vfc_name)) 339 break; 340 } 341 if (vfsp == NULL) 342 return EINVAL; 343 if (vfsp->vfc_refcount) 344 return EBUSY; 345 if (vfc->vfc_vfsops->vfs_uninit != NULL) { 346 error = (*vfc->vfc_vfsops->vfs_uninit)(vfsp); 347 if (error) 348 return (error); 349 } 350 if (prev_vfsp) 351 prev_vfsp->vfc_next = vfsp->vfc_next; 352 else 353 vfsconf = vfsp->vfc_next; 354 maxtypenum = VFS_GENERIC; 355 for (vfsp = vfsconf; vfsp != NULL; vfsp = vfsp->vfc_next) 356 if (maxtypenum < vfsp->vfc_typenum) 357 maxtypenum = vfsp->vfc_typenum; 358 maxvfsconf = maxtypenum + 1; 359 return 0; 360 } 361 362 int 363 vfs_modevent(module_t mod, int type, void *data) 364 { 365 struct vfsconf *vfc; 366 int error = 0; 367 368 vfc = (struct vfsconf *)data; 369 370 switch (type) { 371 case MOD_LOAD: 372 if (vfc) 373 error = vfs_register(vfc); 374 break; 375 376 case MOD_UNLOAD: 377 if (vfc) 378 error = vfs_unregister(vfc); 379 break; 380 default: /* including MOD_SHUTDOWN */ 381 break; 382 } 383 return (error); 384 } 385