vfs_init.c revision 72012
11541Srgrimes/* 21541Srgrimes * Copyright (c) 1989, 1993 31541Srgrimes * The Regents of the University of California. All rights reserved. 41541Srgrimes * 51541Srgrimes * This code is derived from software contributed 61541Srgrimes * to Berkeley by John Heidemann of the UCLA Ficus project. 71541Srgrimes * 81541Srgrimes * Source: * @(#)i405_init.c 2.10 92/04/27 UCLA Ficus project 91541Srgrimes * 101541Srgrimes * Redistribution and use in source and binary forms, with or without 111541Srgrimes * modification, are permitted provided that the following conditions 121541Srgrimes * are met: 131541Srgrimes * 1. Redistributions of source code must retain the above copyright 141541Srgrimes * notice, this list of conditions and the following disclaimer. 151541Srgrimes * 2. Redistributions in binary form must reproduce the above copyright 161541Srgrimes * notice, this list of conditions and the following disclaimer in the 171541Srgrimes * documentation and/or other materials provided with the distribution. 181541Srgrimes * 3. All advertising materials mentioning features or use of this software 191541Srgrimes * must display the following acknowledgement: 201541Srgrimes * This product includes software developed by the University of 211541Srgrimes * California, Berkeley and its contributors. 221541Srgrimes * 4. Neither the name of the University nor the names of its contributors 231541Srgrimes * may be used to endorse or promote products derived from this software 241541Srgrimes * without specific prior written permission. 251541Srgrimes * 261541Srgrimes * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 271541Srgrimes * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 281541Srgrimes * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 291541Srgrimes * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 301541Srgrimes * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 311541Srgrimes * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 321541Srgrimes * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 331541Srgrimes * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 341541Srgrimes * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 351541Srgrimes * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 361541Srgrimes * SUCH DAMAGE. 371541Srgrimes * 381541Srgrimes * @(#)vfs_init.c 8.3 (Berkeley) 1/4/94 3950477Speter * $FreeBSD: head/sys/kern/vfs_init.c 72012 2001-02-04 16:08:18Z phk $ 401541Srgrimes */ 411541Srgrimes 421541Srgrimes 431541Srgrimes#include <sys/param.h> 442112Swollman#include <sys/systm.h> 452946Swollman#include <sys/kernel.h> 461541Srgrimes#include <sys/mount.h> 4738869Sbde#include <sys/sysctl.h> 481541Srgrimes#include <sys/vnode.h> 491541Srgrimes#include <sys/malloc.h> 5029653Sdyson#include <vm/vm_zone.h> 511541Srgrimes 5212577Sbde 5330354SphkMALLOC_DEFINE(M_VNODE, "vnodes", "Dynamically allocated vnodes"); 5430354Sphk 5510358Sjulian/* 5669664Speter * The highest defined VFS number. 5729653Sdyson */ 5869664Speterint maxvfsconf = VFS_GENERIC + 1; 5952780Smsmithstruct vfsconf *vfsconf; 6052780Smsmith 6152780Smsmith/* 621541Srgrimes * vfs_init.c 631541Srgrimes * 641541Srgrimes * Allocate and fill in operations vectors. 651541Srgrimes * 661541Srgrimes * An undocumented feature of this approach to defining operations is that 671541Srgrimes * there can be multiple entries in vfs_opv_descs for the same operations 681541Srgrimes * vector. This allows third parties to extend the set of operations 691541Srgrimes * supported by another layer in a binary compatibile way. For example, 701541Srgrimes * assume that NFS needed to be modified to support Ficus. NFS has an entry 711541Srgrimes * (probably nfs_vnopdeop_decls) declaring all the operations NFS supports by 721541Srgrimes * default. Ficus could add another entry (ficus_nfs_vnodeop_decl_entensions) 731541Srgrimes * listing those new operations Ficus adds to NFS, all without modifying the 741541Srgrimes * NFS code. (Of couse, the OTW NFS protocol still needs to be munged, but 751541Srgrimes * that is a(whole)nother story.) This is a feature. 761541Srgrimes */ 7741056Speter 7841056Speter/* Table of known vnodeop vectors (list of VFS vnode vectors) */ 7943311Sdillonstatic const struct vnodeopv_desc **vnodeopv_descs; 8041056Speterstatic int vnodeopv_num; 8141056Speter 8241056Speter/* Table of known descs (list of vnode op handlers "vop_access_desc") */ 8341056Speterstatic struct vnodeop_desc **vfs_op_descs; 8441056Speterstatic int *vfs_op_desc_refs; /* reference counts */ 8541056Speterstatic int num_op_descs; 8641056Speterstatic int vfs_opv_numops; 8741056Speter 8841056Speterstatic void 8941056Spetervfs_opv_recalc(void) 901541Srgrimes{ 9141056Speter int i, j; 9212158Sbde vop_t ***opv_desc_vector_p; 9312158Sbde vop_t **opv_desc_vector; 941541Srgrimes struct vnodeopv_entry_desc *opve_descp; 9543311Sdillon const struct vnodeopv_desc *opv; 961541Srgrimes 9741056Speter if (vfs_op_descs == NULL) 9841056Speter panic("vfs_opv_recalc called with null vfs_op_descs"); 9941056Speter 1001541Srgrimes /* 10141056Speter * Run through and make sure all known descs have an offset 10241056Speter * 10341056Speter * vop_default_desc is hardwired at offset 1, and offset 0 10441056Speter * is a panic sanity check. 1051541Srgrimes */ 10641056Speter vfs_opv_numops = 0; 10741056Speter for (i = 0; i < num_op_descs; i++) 10841056Speter if (vfs_opv_numops < (vfs_op_descs[i]->vdesc_offset + 1)) 10941056Speter vfs_opv_numops = vfs_op_descs[i]->vdesc_offset + 1; 11041056Speter for (i = 0; i < num_op_descs; i++) 11141056Speter if (vfs_op_descs[i]->vdesc_offset == 0) 11241056Speter vfs_op_descs[i]->vdesc_offset = vfs_opv_numops++; 11340435Speter /* 11441056Speter * Allocate and fill in the vectors 11540435Speter */ 11641056Speter for (i = 0; i < vnodeopv_num; i++) { 11741056Speter opv = vnodeopv_descs[i]; 11841056Speter opv_desc_vector_p = opv->opv_desc_vector_p; 11941056Speter if (*opv_desc_vector_p) 12041056Speter FREE(*opv_desc_vector_p, M_VNODE); 12140435Speter MALLOC(*opv_desc_vector_p, vop_t **, 12269781Sdwmalone vfs_opv_numops * sizeof(vop_t *), M_VNODE, 12369781Sdwmalone M_WAITOK | M_ZERO); 12441056Speter if (*opv_desc_vector_p == NULL) 12541056Speter panic("no memory for vop_t ** vector"); 12641056Speter 12765527Speter /* Fill in, with slot 0 being to return EOPNOTSUPP */ 12841056Speter opv_desc_vector = *opv_desc_vector_p; 12965527Speter opv_desc_vector[0] = (vop_t *)vop_eopnotsupp; 13041056Speter for (j = 0; opv->opv_desc_ops[j].opve_op; j++) { 13141056Speter opve_descp = &(opv->opv_desc_ops[j]); 13241056Speter opv_desc_vector[opve_descp->opve_op->vdesc_offset] = 13341056Speter opve_descp->opve_impl; 13441056Speter } 13541056Speter 13641056Speter /* Replace unfilled routines with their default (slot 1). */ 13741056Speter opv_desc_vector = *(opv->opv_desc_vector_p); 13841056Speter if (opv_desc_vector[1] == NULL) 13941056Speter panic("vfs_opv_recalc: vector without a default."); 14041056Speter for (j = 0; j < vfs_opv_numops; j++) 14141056Speter if (opv_desc_vector[j] == NULL) 14241056Speter opv_desc_vector[j] = opv_desc_vector[1]; 14340435Speter } 14441056Speter} 14540435Speter 14641056Spetervoid 14743311Sdillonvfs_add_vnodeops(const void *data) 14841056Speter{ 14943311Sdillon const struct vnodeopv_desc *opv; 15043311Sdillon const struct vnodeopv_desc **newopv; 15141056Speter struct vnodeop_desc **newop; 15241056Speter int *newref; 15341056Speter vop_t **opv_desc_vector; 15441056Speter struct vnodeop_desc *desc; 15541591Sarchie int i, j; 15641056Speter 15743311Sdillon opv = (const struct vnodeopv_desc *)data; 15843311Sdillon MALLOC(newopv, const struct vnodeopv_desc **, 15941056Speter (vnodeopv_num + 1) * sizeof(*newopv), M_VNODE, M_WAITOK); 16041056Speter if (newopv == NULL) 16141056Speter panic("vfs_add_vnodeops: no memory"); 16241056Speter if (vnodeopv_descs) { 16341056Speter bcopy(vnodeopv_descs, newopv, vnodeopv_num * sizeof(*newopv)); 16441056Speter FREE(vnodeopv_descs, M_VNODE); 16541056Speter } 16641056Speter newopv[vnodeopv_num] = opv; 16741056Speter vnodeopv_descs = newopv; 16841056Speter vnodeopv_num++; 16941056Speter 17041056Speter /* See if we have turned up a new vnode op desc */ 17141056Speter opv_desc_vector = *(opv->opv_desc_vector_p); 17241056Speter for (i = 0; (desc = opv->opv_desc_ops[i].opve_op); i++) { 17341056Speter for (j = 0; j < num_op_descs; j++) { 17441056Speter if (desc == vfs_op_descs[j]) { 17541056Speter /* found it, increase reference count */ 17641056Speter vfs_op_desc_refs[j]++; 17741056Speter break; 17841056Speter } 1791541Srgrimes } 18041056Speter if (j == num_op_descs) { 18141056Speter /* not found, new entry */ 18241056Speter MALLOC(newop, struct vnodeop_desc **, 18341056Speter (num_op_descs + 1) * sizeof(*newop), 18441056Speter M_VNODE, M_WAITOK); 18541056Speter if (newop == NULL) 18641056Speter panic("vfs_add_vnodeops: no memory for desc"); 18741056Speter /* new reference count (for unload) */ 18841056Speter MALLOC(newref, int *, 18941056Speter (num_op_descs + 1) * sizeof(*newref), 19041056Speter M_VNODE, M_WAITOK); 19141056Speter if (newref == NULL) 19241056Speter panic("vfs_add_vnodeops: no memory for refs"); 19341056Speter if (vfs_op_descs) { 19441056Speter bcopy(vfs_op_descs, newop, 19541056Speter num_op_descs * sizeof(*newop)); 19641056Speter FREE(vfs_op_descs, M_VNODE); 19741056Speter } 19841056Speter if (vfs_op_desc_refs) { 19941056Speter bcopy(vfs_op_desc_refs, newref, 20041056Speter num_op_descs * sizeof(*newref)); 20141056Speter FREE(vfs_op_desc_refs, M_VNODE); 20241056Speter } 20341056Speter newop[num_op_descs] = desc; 20441056Speter newref[num_op_descs] = 1; 20541056Speter vfs_op_descs = newop; 20641056Speter vfs_op_desc_refs = newref; 20741056Speter num_op_descs++; 20841056Speter } 2091541Srgrimes } 21041056Speter vfs_opv_recalc(); 2111541Srgrimes} 2121541Srgrimes 21341056Spetervoid 21443311Sdillonvfs_rm_vnodeops(const void *data) 2151541Srgrimes{ 21643311Sdillon const struct vnodeopv_desc *opv; 21743311Sdillon const struct vnodeopv_desc **newopv; 21841056Speter struct vnodeop_desc **newop; 21941056Speter int *newref; 22041056Speter vop_t **opv_desc_vector; 22141056Speter struct vnodeop_desc *desc; 22241056Speter int i, j, k; 2231541Srgrimes 22443351Sdillon opv = (const struct vnodeopv_desc *)data; 22541056Speter /* Lower ref counts on descs in the table and release if zero */ 22641056Speter opv_desc_vector = *(opv->opv_desc_vector_p); 22741056Speter for (i = 0; (desc = opv->opv_desc_ops[i].opve_op); i++) { 22841056Speter for (j = 0; j < num_op_descs; j++) { 22941056Speter if (desc == vfs_op_descs[j]) { 23041056Speter /* found it, decrease reference count */ 23141056Speter vfs_op_desc_refs[j]--; 23241056Speter break; 23341056Speter } 23441056Speter } 23541056Speter for (j = 0; j < num_op_descs; j++) { 23641056Speter if (vfs_op_desc_refs[j] > 0) 23741056Speter continue; 23841056Speter if (vfs_op_desc_refs[j] < 0) 23941056Speter panic("vfs_remove_vnodeops: negative refcnt"); 24041056Speter MALLOC(newop, struct vnodeop_desc **, 24141056Speter (num_op_descs - 1) * sizeof(*newop), 24241056Speter M_VNODE, M_WAITOK); 24341056Speter if (newop == NULL) 24441056Speter panic("vfs_remove_vnodeops: no memory for desc"); 24541056Speter /* new reference count (for unload) */ 24641056Speter MALLOC(newref, int *, 24741056Speter (num_op_descs - 1) * sizeof(*newref), 24841056Speter M_VNODE, M_WAITOK); 24941056Speter if (newref == NULL) 25041056Speter panic("vfs_remove_vnodeops: no memory for refs"); 25141056Speter for (k = j; k < (num_op_descs - 1); k++) { 25241056Speter vfs_op_descs[k] = vfs_op_descs[k + 1]; 25341056Speter vfs_op_desc_refs[k] = vfs_op_desc_refs[k + 1]; 25441056Speter } 25541056Speter bcopy(vfs_op_descs, newop, 25641056Speter (num_op_descs - 1) * sizeof(*newop)); 25741056Speter bcopy(vfs_op_desc_refs, newref, 25841056Speter (num_op_descs - 1) * sizeof(*newref)); 25941056Speter FREE(vfs_op_descs, M_VNODE); 26041056Speter FREE(vfs_op_desc_refs, M_VNODE); 26141056Speter vfs_op_descs = newop; 26241056Speter vfs_op_desc_refs = newref; 26341056Speter num_op_descs--; 26441056Speter } 26541056Speter } 26641056Speter 26741056Speter for (i = 0; i < vnodeopv_num; i++) { 26841056Speter if (vnodeopv_descs[i] == opv) { 26941056Speter for (j = i; j < (vnodeopv_num - 1); j++) 27041056Speter vnodeopv_descs[j] = vnodeopv_descs[j + 1]; 27141056Speter break; 27241056Speter } 27341056Speter } 27441056Speter if (i == vnodeopv_num) 27541056Speter panic("vfs_remove_vnodeops: opv not found"); 27643311Sdillon MALLOC(newopv, const struct vnodeopv_desc **, 27741056Speter (vnodeopv_num - 1) * sizeof(*newopv), M_VNODE, M_WAITOK); 27841056Speter if (newopv == NULL) 27941056Speter panic("vfs_remove_vnodeops: no memory"); 28041056Speter bcopy(vnodeopv_descs, newopv, (vnodeopv_num - 1) * sizeof(*newopv)); 28141056Speter FREE(vnodeopv_descs, M_VNODE); 28241056Speter vnodeopv_descs = newopv; 28341056Speter vnodeopv_num--; 28441056Speter 28541056Speter vfs_opv_recalc(); 2861541Srgrimes} 2871541Srgrimes 2881541Srgrimes/* 2891541Srgrimes * Routines having to do with the management of the vnode table. 2901541Srgrimes */ 2911541Srgrimesstruct vattr va_null; 2921541Srgrimes 2931541Srgrimes/* 2941541Srgrimes * Initialize the vnode structures and initialize each file system type. 2951541Srgrimes */ 29610358Sjulian/* ARGSUSED*/ 29710358Sjulianstatic void 29841056Spetervfsinit(void *dummy) 2991541Srgrimes{ 3001541Srgrimes 3011541Srgrimes vattr_null(&va_null); 30240435Speter} 30341056SpeterSYSINIT(vfs, SI_SUB_VFS, SI_ORDER_FIRST, vfsinit, NULL) 30440435Speter 30540435Speterint 30641056Spetervfs_register(struct vfsconf *vfc) 30740435Speter{ 30844549Sdfr struct sysctl_oid *oidp; 30940435Speter struct vfsconf *vfsp; 31040435Speter 31140435Speter vfsp = NULL; 31240435Speter if (vfsconf) 31340435Speter for (vfsp = vfsconf; vfsp->vfc_next; vfsp = vfsp->vfc_next) 31444549Sdfr if (strcmp(vfc->vfc_name, vfsp->vfc_name) == 0) 31540435Speter return EEXIST; 31640435Speter 31740435Speter vfc->vfc_typenum = maxvfsconf++; 31840435Speter if (vfsp) 31940435Speter vfsp->vfc_next = vfc; 32040435Speter else 32140435Speter vfsconf = vfc; 32240435Speter vfc->vfc_next = NULL; 32340435Speter 32440435Speter /* 32544549Sdfr * If this filesystem has a sysctl node under vfs 32644549Sdfr * (i.e. vfs.xxfs), then change the oid number of that node to 32744549Sdfr * match the filesystem's type number. This allows user code 32844549Sdfr * which uses the type number to read sysctl variables defined 32944549Sdfr * by the filesystem to continue working. Since the oids are 33044549Sdfr * in a sorted list, we need to make sure the order is 33144549Sdfr * preserved by re-registering the oid after modifying its 33244549Sdfr * number. 33344549Sdfr */ 33472012Sphk SLIST_FOREACH(oidp, &sysctl__vfs_children, oid_link) 33544549Sdfr if (strcmp(oidp->oid_name, vfc->vfc_name) == 0) { 33644549Sdfr sysctl_unregister_oid(oidp); 33744549Sdfr oidp->oid_number = vfc->vfc_typenum; 33844549Sdfr sysctl_register_oid(oidp); 33944549Sdfr } 34044549Sdfr 34144549Sdfr /* 34240435Speter * Call init function for this VFS... 34340435Speter */ 34440435Speter (*(vfc->vfc_vfsops->vfs_init))(vfc); 34540435Speter 34640435Speter return 0; 3471541Srgrimes} 3482946Swollman 34940435Speter 35040435Speterint 35141056Spetervfs_unregister(struct vfsconf *vfc) 35240435Speter{ 35340435Speter struct vfsconf *vfsp, *prev_vfsp; 35440435Speter int error, i, maxtypenum; 35540435Speter 35640435Speter i = vfc->vfc_typenum; 35740435Speter 35840435Speter prev_vfsp = NULL; 35940435Speter for (vfsp = vfsconf; vfsp; 36040435Speter prev_vfsp = vfsp, vfsp = vfsp->vfc_next) { 36140435Speter if (!strcmp(vfc->vfc_name, vfsp->vfc_name)) 36240435Speter break; 36340435Speter } 36440435Speter if (vfsp == NULL) 36540435Speter return EINVAL; 36640435Speter if (vfsp->vfc_refcount) 36740435Speter return EBUSY; 36840435Speter if (vfc->vfc_vfsops->vfs_uninit != NULL) { 36940435Speter error = (*vfc->vfc_vfsops->vfs_uninit)(vfsp); 37040435Speter if (error) 37140435Speter return (error); 37240435Speter } 37340435Speter if (prev_vfsp) 37440435Speter prev_vfsp->vfc_next = vfsp->vfc_next; 37540435Speter else 37640435Speter vfsconf = vfsp->vfc_next; 37740435Speter maxtypenum = VFS_GENERIC; 37840435Speter for (vfsp = vfsconf; vfsp != NULL; vfsp = vfsp->vfc_next) 37940435Speter if (maxtypenum < vfsp->vfc_typenum) 38040435Speter maxtypenum = vfsp->vfc_typenum; 38140435Speter maxvfsconf = maxtypenum + 1; 38240435Speter return 0; 38340435Speter} 38441056Speter 38541056Speterint 38641170Sbdevfs_modevent(module_t mod, int type, void *data) 38741056Speter{ 38841056Speter struct vfsconf *vfc; 38941056Speter int error = 0; 39041056Speter 39141056Speter vfc = (struct vfsconf *)data; 39241056Speter 39341056Speter switch (type) { 39441056Speter case MOD_LOAD: 39541056Speter if (vfc) 39641056Speter error = vfs_register(vfc); 39741056Speter break; 39841056Speter 39941056Speter case MOD_UNLOAD: 40041056Speter if (vfc) 40141056Speter error = vfs_unregister(vfc); 40241056Speter break; 40341056Speter default: /* including MOD_SHUTDOWN */ 40441056Speter break; 40541056Speter } 40641056Speter return (error); 40741056Speter} 408