vfs_init.c revision 52780
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 52780 1999-11-01 23:54:07Z msmith $ 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/* 5640435Speter * XXX this bloat just exands the sysctl__vfs linker set a little so that 5740435Speter * we can attach sysctls for VFS modules without expanding the linker set. 5840435Speter * Currently (1998/09/06), only one VFS uses sysctls, so 2 extra linker 5940435Speter * set slots are more than sufficient. 6040435Speter */ 6140435Speterstatic int mod_xx; 6240435SpeterSYSCTL_INT(_vfs, OID_AUTO, mod0, CTLFLAG_RD, &mod_xx, 0, ""); 6340435SpeterSYSCTL_INT(_vfs, OID_AUTO, mod1, CTLFLAG_RD, &mod_xx, 0, ""); 6440435Speter 6540435Speter/* 6629653Sdyson * Zone for namei 6729653Sdyson */ 6829653Sdysonstruct vm_zone *namei_zone; 6929653Sdyson 7029653Sdyson/* 7152780Smsmith * vfs_init() will set maxvfsconf 7252780Smsmith * to the highest defined type number. 7352780Smsmith */ 7452780Smsmithint maxvfsconf; 7552780Smsmithstruct vfsconf *vfsconf; 7652780Smsmith 7752780Smsmith/* 781541Srgrimes * vfs_init.c 791541Srgrimes * 801541Srgrimes * Allocate and fill in operations vectors. 811541Srgrimes * 821541Srgrimes * An undocumented feature of this approach to defining operations is that 831541Srgrimes * there can be multiple entries in vfs_opv_descs for the same operations 841541Srgrimes * vector. This allows third parties to extend the set of operations 851541Srgrimes * supported by another layer in a binary compatibile way. For example, 861541Srgrimes * assume that NFS needed to be modified to support Ficus. NFS has an entry 871541Srgrimes * (probably nfs_vnopdeop_decls) declaring all the operations NFS supports by 881541Srgrimes * default. Ficus could add another entry (ficus_nfs_vnodeop_decl_entensions) 891541Srgrimes * listing those new operations Ficus adds to NFS, all without modifying the 901541Srgrimes * NFS code. (Of couse, the OTW NFS protocol still needs to be munged, but 911541Srgrimes * that is a(whole)nother story.) This is a feature. 921541Srgrimes */ 9341056Speter 9441056Speter/* Table of known vnodeop vectors (list of VFS vnode vectors) */ 9543311Sdillonstatic const struct vnodeopv_desc **vnodeopv_descs; 9641056Speterstatic int vnodeopv_num; 9741056Speter 9841056Speter/* Table of known descs (list of vnode op handlers "vop_access_desc") */ 9941056Speterstatic struct vnodeop_desc **vfs_op_descs; 10041056Speterstatic int *vfs_op_desc_refs; /* reference counts */ 10141056Speterstatic int num_op_descs; 10241056Speterstatic int vfs_opv_numops; 10341056Speter 10441056Speterstatic void 10541056Spetervfs_opv_recalc(void) 1061541Srgrimes{ 10741056Speter int i, j; 10812158Sbde vop_t ***opv_desc_vector_p; 10912158Sbde vop_t **opv_desc_vector; 1101541Srgrimes struct vnodeopv_entry_desc *opve_descp; 11143311Sdillon const struct vnodeopv_desc *opv; 1121541Srgrimes 11341056Speter if (vfs_op_descs == NULL) 11441056Speter panic("vfs_opv_recalc called with null vfs_op_descs"); 11541056Speter 1161541Srgrimes /* 11741056Speter * Run through and make sure all known descs have an offset 11841056Speter * 11941056Speter * vop_default_desc is hardwired at offset 1, and offset 0 12041056Speter * is a panic sanity check. 1211541Srgrimes */ 12241056Speter vfs_opv_numops = 0; 12341056Speter for (i = 0; i < num_op_descs; i++) 12441056Speter if (vfs_opv_numops < (vfs_op_descs[i]->vdesc_offset + 1)) 12541056Speter vfs_opv_numops = vfs_op_descs[i]->vdesc_offset + 1; 12641056Speter for (i = 0; i < num_op_descs; i++) 12741056Speter if (vfs_op_descs[i]->vdesc_offset == 0) 12841056Speter vfs_op_descs[i]->vdesc_offset = vfs_opv_numops++; 12940435Speter /* 13041056Speter * Allocate and fill in the vectors 13140435Speter */ 13241056Speter for (i = 0; i < vnodeopv_num; i++) { 13341056Speter opv = vnodeopv_descs[i]; 13441056Speter opv_desc_vector_p = opv->opv_desc_vector_p; 13541056Speter if (*opv_desc_vector_p) 13641056Speter FREE(*opv_desc_vector_p, M_VNODE); 13740435Speter MALLOC(*opv_desc_vector_p, vop_t **, 13840880Speter vfs_opv_numops * sizeof(vop_t *), M_VNODE, M_WAITOK); 13941056Speter if (*opv_desc_vector_p == NULL) 14041056Speter panic("no memory for vop_t ** vector"); 14141056Speter bzero(*opv_desc_vector_p, vfs_opv_numops * sizeof(vop_t *)); 14241056Speter 14341056Speter /* Fill in, with slot 0 being panic */ 14441056Speter opv_desc_vector = *opv_desc_vector_p; 14541056Speter opv_desc_vector[0] = (vop_t *)vop_panic; 14641056Speter for (j = 0; opv->opv_desc_ops[j].opve_op; j++) { 14741056Speter opve_descp = &(opv->opv_desc_ops[j]); 14841056Speter opv_desc_vector[opve_descp->opve_op->vdesc_offset] = 14941056Speter opve_descp->opve_impl; 15041056Speter } 15141056Speter 15241056Speter /* Replace unfilled routines with their default (slot 1). */ 15341056Speter opv_desc_vector = *(opv->opv_desc_vector_p); 15441056Speter if (opv_desc_vector[1] == NULL) 15541056Speter panic("vfs_opv_recalc: vector without a default."); 15641056Speter for (j = 0; j < vfs_opv_numops; j++) 15741056Speter if (opv_desc_vector[j] == NULL) 15841056Speter opv_desc_vector[j] = opv_desc_vector[1]; 15940435Speter } 16041056Speter} 16140435Speter 16241056Spetervoid 16343311Sdillonvfs_add_vnodeops(const void *data) 16441056Speter{ 16543311Sdillon const struct vnodeopv_desc *opv; 16643311Sdillon const struct vnodeopv_desc **newopv; 16741056Speter struct vnodeop_desc **newop; 16841056Speter int *newref; 16941056Speter vop_t **opv_desc_vector; 17041056Speter struct vnodeop_desc *desc; 17141591Sarchie int i, j; 17241056Speter 17343311Sdillon opv = (const struct vnodeopv_desc *)data; 17443311Sdillon MALLOC(newopv, const struct vnodeopv_desc **, 17541056Speter (vnodeopv_num + 1) * sizeof(*newopv), M_VNODE, M_WAITOK); 17641056Speter if (newopv == NULL) 17741056Speter panic("vfs_add_vnodeops: no memory"); 17841056Speter if (vnodeopv_descs) { 17941056Speter bcopy(vnodeopv_descs, newopv, vnodeopv_num * sizeof(*newopv)); 18041056Speter FREE(vnodeopv_descs, M_VNODE); 18141056Speter } 18241056Speter newopv[vnodeopv_num] = opv; 18341056Speter vnodeopv_descs = newopv; 18441056Speter vnodeopv_num++; 18541056Speter 18641056Speter /* See if we have turned up a new vnode op desc */ 18741056Speter opv_desc_vector = *(opv->opv_desc_vector_p); 18841056Speter for (i = 0; (desc = opv->opv_desc_ops[i].opve_op); i++) { 18941056Speter for (j = 0; j < num_op_descs; j++) { 19041056Speter if (desc == vfs_op_descs[j]) { 19141056Speter /* found it, increase reference count */ 19241056Speter vfs_op_desc_refs[j]++; 19341056Speter break; 19441056Speter } 1951541Srgrimes } 19641056Speter if (j == num_op_descs) { 19741056Speter /* not found, new entry */ 19841056Speter MALLOC(newop, struct vnodeop_desc **, 19941056Speter (num_op_descs + 1) * sizeof(*newop), 20041056Speter M_VNODE, M_WAITOK); 20141056Speter if (newop == NULL) 20241056Speter panic("vfs_add_vnodeops: no memory for desc"); 20341056Speter /* new reference count (for unload) */ 20441056Speter MALLOC(newref, int *, 20541056Speter (num_op_descs + 1) * sizeof(*newref), 20641056Speter M_VNODE, M_WAITOK); 20741056Speter if (newref == NULL) 20841056Speter panic("vfs_add_vnodeops: no memory for refs"); 20941056Speter if (vfs_op_descs) { 21041056Speter bcopy(vfs_op_descs, newop, 21141056Speter num_op_descs * sizeof(*newop)); 21241056Speter FREE(vfs_op_descs, M_VNODE); 21341056Speter } 21441056Speter if (vfs_op_desc_refs) { 21541056Speter bcopy(vfs_op_desc_refs, newref, 21641056Speter num_op_descs * sizeof(*newref)); 21741056Speter FREE(vfs_op_desc_refs, M_VNODE); 21841056Speter } 21941056Speter newop[num_op_descs] = desc; 22041056Speter newref[num_op_descs] = 1; 22141056Speter vfs_op_descs = newop; 22241056Speter vfs_op_desc_refs = newref; 22341056Speter num_op_descs++; 22441056Speter } 2251541Srgrimes } 22641056Speter vfs_opv_recalc(); 2271541Srgrimes} 2281541Srgrimes 22941056Spetervoid 23043311Sdillonvfs_rm_vnodeops(const void *data) 2311541Srgrimes{ 23243311Sdillon const struct vnodeopv_desc *opv; 23343311Sdillon const struct vnodeopv_desc **newopv; 23441056Speter struct vnodeop_desc **newop; 23541056Speter int *newref; 23641056Speter vop_t **opv_desc_vector; 23741056Speter struct vnodeop_desc *desc; 23841056Speter int i, j, k; 2391541Srgrimes 24043351Sdillon opv = (const struct vnodeopv_desc *)data; 24141056Speter /* Lower ref counts on descs in the table and release if zero */ 24241056Speter opv_desc_vector = *(opv->opv_desc_vector_p); 24341056Speter for (i = 0; (desc = opv->opv_desc_ops[i].opve_op); i++) { 24441056Speter for (j = 0; j < num_op_descs; j++) { 24541056Speter if (desc == vfs_op_descs[j]) { 24641056Speter /* found it, decrease reference count */ 24741056Speter vfs_op_desc_refs[j]--; 24841056Speter break; 24941056Speter } 25041056Speter } 25141056Speter for (j = 0; j < num_op_descs; j++) { 25241056Speter if (vfs_op_desc_refs[j] > 0) 25341056Speter continue; 25441056Speter if (vfs_op_desc_refs[j] < 0) 25541056Speter panic("vfs_remove_vnodeops: negative refcnt"); 25641056Speter MALLOC(newop, struct vnodeop_desc **, 25741056Speter (num_op_descs - 1) * sizeof(*newop), 25841056Speter M_VNODE, M_WAITOK); 25941056Speter if (newop == NULL) 26041056Speter panic("vfs_remove_vnodeops: no memory for desc"); 26141056Speter /* new reference count (for unload) */ 26241056Speter MALLOC(newref, int *, 26341056Speter (num_op_descs - 1) * sizeof(*newref), 26441056Speter M_VNODE, M_WAITOK); 26541056Speter if (newref == NULL) 26641056Speter panic("vfs_remove_vnodeops: no memory for refs"); 26741056Speter for (k = j; k < (num_op_descs - 1); k++) { 26841056Speter vfs_op_descs[k] = vfs_op_descs[k + 1]; 26941056Speter vfs_op_desc_refs[k] = vfs_op_desc_refs[k + 1]; 27041056Speter } 27141056Speter bcopy(vfs_op_descs, newop, 27241056Speter (num_op_descs - 1) * sizeof(*newop)); 27341056Speter bcopy(vfs_op_desc_refs, newref, 27441056Speter (num_op_descs - 1) * sizeof(*newref)); 27541056Speter FREE(vfs_op_descs, M_VNODE); 27641056Speter FREE(vfs_op_desc_refs, M_VNODE); 27741056Speter vfs_op_descs = newop; 27841056Speter vfs_op_desc_refs = newref; 27941056Speter num_op_descs--; 28041056Speter } 28141056Speter } 28241056Speter 28341056Speter for (i = 0; i < vnodeopv_num; i++) { 28441056Speter if (vnodeopv_descs[i] == opv) { 28541056Speter for (j = i; j < (vnodeopv_num - 1); j++) 28641056Speter vnodeopv_descs[j] = vnodeopv_descs[j + 1]; 28741056Speter break; 28841056Speter } 28941056Speter } 29041056Speter if (i == vnodeopv_num) 29141056Speter panic("vfs_remove_vnodeops: opv not found"); 29243311Sdillon MALLOC(newopv, const struct vnodeopv_desc **, 29341056Speter (vnodeopv_num - 1) * sizeof(*newopv), M_VNODE, M_WAITOK); 29441056Speter if (newopv == NULL) 29541056Speter panic("vfs_remove_vnodeops: no memory"); 29641056Speter bcopy(vnodeopv_descs, newopv, (vnodeopv_num - 1) * sizeof(*newopv)); 29741056Speter FREE(vnodeopv_descs, M_VNODE); 29841056Speter vnodeopv_descs = newopv; 29941056Speter vnodeopv_num--; 30041056Speter 30141056Speter vfs_opv_recalc(); 3021541Srgrimes} 3031541Srgrimes 3041541Srgrimes/* 3051541Srgrimes * Routines having to do with the management of the vnode table. 3061541Srgrimes */ 3071541Srgrimesstruct vattr va_null; 3081541Srgrimes 3091541Srgrimes/* 3101541Srgrimes * Initialize the vnode structures and initialize each file system type. 3111541Srgrimes */ 31210358Sjulian/* ARGSUSED*/ 31310358Sjulianstatic void 31441056Spetervfsinit(void *dummy) 3151541Srgrimes{ 3161541Srgrimes 31729653Sdyson namei_zone = zinit("NAMEI", MAXPATHLEN, 0, 0, 2); 31829653Sdyson 3191541Srgrimes /* 3201541Srgrimes * Initialize the vnode table 3211541Srgrimes */ 3221541Srgrimes vntblinit(); 3231541Srgrimes /* 3241541Srgrimes * Initialize the vnode name cache 3251541Srgrimes */ 3261541Srgrimes nchinit(); 3271541Srgrimes /* 3281541Srgrimes * Initialize each file system type. 32939975Sobrien * Vfs type numbers must be distinct from VFS_GENERIC (and VFS_VFSCONF). 3301541Srgrimes */ 3311541Srgrimes vattr_null(&va_null); 33240435Speter maxvfsconf = VFS_GENERIC + 1; 33340435Speter} 33441056SpeterSYSINIT(vfs, SI_SUB_VFS, SI_ORDER_FIRST, vfsinit, NULL) 33540435Speter 33640435Speterint 33741056Spetervfs_register(struct vfsconf *vfc) 33840435Speter{ 33944549Sdfr struct sysctl_oid *oidp; 34040435Speter struct vfsconf *vfsp; 34140435Speter 34240435Speter vfsp = NULL; 34340435Speter if (vfsconf) 34440435Speter for (vfsp = vfsconf; vfsp->vfc_next; vfsp = vfsp->vfc_next) 34544549Sdfr if (strcmp(vfc->vfc_name, vfsp->vfc_name) == 0) 34640435Speter return EEXIST; 34740435Speter 34840435Speter vfc->vfc_typenum = maxvfsconf++; 34940435Speter if (vfsp) 35040435Speter vfsp->vfc_next = vfc; 35140435Speter else 35240435Speter vfsconf = vfc; 35340435Speter vfc->vfc_next = NULL; 35440435Speter 35540435Speter /* 35644549Sdfr * If this filesystem has a sysctl node under vfs 35744549Sdfr * (i.e. vfs.xxfs), then change the oid number of that node to 35844549Sdfr * match the filesystem's type number. This allows user code 35944549Sdfr * which uses the type number to read sysctl variables defined 36044549Sdfr * by the filesystem to continue working. Since the oids are 36144549Sdfr * in a sorted list, we need to make sure the order is 36244549Sdfr * preserved by re-registering the oid after modifying its 36344549Sdfr * number. 36444549Sdfr */ 36544549Sdfr for (oidp = SLIST_FIRST(&sysctl__vfs_children); oidp; 36644549Sdfr oidp = SLIST_NEXT(oidp, oid_link)) 36744549Sdfr if (strcmp(oidp->oid_name, vfc->vfc_name) == 0) { 36844549Sdfr sysctl_unregister_oid(oidp); 36944549Sdfr oidp->oid_number = vfc->vfc_typenum; 37044549Sdfr sysctl_register_oid(oidp); 37144549Sdfr } 37244549Sdfr 37344549Sdfr /* 37440435Speter * Call init function for this VFS... 37540435Speter */ 37640435Speter (*(vfc->vfc_vfsops->vfs_init))(vfc); 37740435Speter 37840435Speter return 0; 3791541Srgrimes} 3802946Swollman 38140435Speter 38240435Speterint 38341056Spetervfs_unregister(struct vfsconf *vfc) 38440435Speter{ 38540435Speter struct vfsconf *vfsp, *prev_vfsp; 38640435Speter int error, i, maxtypenum; 38740435Speter 38840435Speter i = vfc->vfc_typenum; 38940435Speter 39040435Speter prev_vfsp = NULL; 39140435Speter for (vfsp = vfsconf; vfsp; 39240435Speter prev_vfsp = vfsp, vfsp = vfsp->vfc_next) { 39340435Speter if (!strcmp(vfc->vfc_name, vfsp->vfc_name)) 39440435Speter break; 39540435Speter } 39640435Speter if (vfsp == NULL) 39740435Speter return EINVAL; 39840435Speter if (vfsp->vfc_refcount) 39940435Speter return EBUSY; 40040435Speter if (vfc->vfc_vfsops->vfs_uninit != NULL) { 40140435Speter error = (*vfc->vfc_vfsops->vfs_uninit)(vfsp); 40240435Speter if (error) 40340435Speter return (error); 40440435Speter } 40540435Speter if (prev_vfsp) 40640435Speter prev_vfsp->vfc_next = vfsp->vfc_next; 40740435Speter else 40840435Speter vfsconf = vfsp->vfc_next; 40940435Speter maxtypenum = VFS_GENERIC; 41040435Speter for (vfsp = vfsconf; vfsp != NULL; vfsp = vfsp->vfc_next) 41140435Speter if (maxtypenum < vfsp->vfc_typenum) 41240435Speter maxtypenum = vfsp->vfc_typenum; 41340435Speter maxvfsconf = maxtypenum + 1; 41440435Speter return 0; 41540435Speter} 41641056Speter 41741056Speterint 41841170Sbdevfs_modevent(module_t mod, int type, void *data) 41941056Speter{ 42041056Speter struct vfsconf *vfc; 42141056Speter int error = 0; 42241056Speter 42341056Speter vfc = (struct vfsconf *)data; 42441056Speter 42541056Speter switch (type) { 42641056Speter case MOD_LOAD: 42741056Speter if (vfc) 42841056Speter error = vfs_register(vfc); 42941056Speter break; 43041056Speter 43141056Speter case MOD_UNLOAD: 43241056Speter if (vfc) 43341056Speter error = vfs_unregister(vfc); 43441056Speter break; 43541056Speter default: /* including MOD_SHUTDOWN */ 43641056Speter break; 43741056Speter } 43841056Speter return (error); 43941056Speter} 440