/* * Copyright (c) 2000-2002 Apple Computer, Inc. All rights reserved. * * @APPLE_LICENSE_HEADER_START@ * * The contents of this file constitute Original Code as defined in and * are subject to the Apple Public Source License Version 1.1 (the * "License"). You may not use this file except in compliance with the * License. Please obtain a copy of the License at * http://www.apple.com/publicsource and read it before using this file. * * This Original Code and all software distributed under the License are * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT. Please see the * License for the specific language governing rights and limitations * under the License. * * @APPLE_LICENSE_HEADER_END@ */ /* Copyright (c) 1995 NeXT Computer, Inc. All Rights Reserved */ /* * Copyright (c) 1989, 1993 * The Regents of the University of California. All rights reserved. * * This code is derived from software contributed * to Berkeley by John Heidemann of the UCLA Ficus project. * * Source: * @(#)i405_init.c 2.10 92/04/27 UCLA Ficus project * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by the University of * California, Berkeley and its contributors. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)vfs_init.c 8.5 (Berkeley) 5/11/95 */ #include <sys/param.h> #include <sys/mount.h> #include <sys/time.h> #include <sys/vm.h> #include <sys/vnode.h> #include <sys/stat.h> #include <sys/namei.h> #include <sys/ucred.h> #include <sys/buf.h> #include <sys/errno.h> #include <sys/malloc.h> /* * Sigh, such primitive tools are these... */ #if 0 #define DODEBUG(A) A #else #define DODEBUG(A) #endif extern uid_t console_user; extern struct vnodeopv_desc *vfs_opv_descs[]; /* a list of lists of vnodeops defns */ extern struct vnodeop_desc *vfs_op_descs[]; /* and the operations they perform */ /* * This code doesn't work if the defn is **vnodop_defns with cc. * The problem is because of the compiler sometimes putting in an * extra level of indirection for arrays. It's an interesting * "feature" of C. */ int vfs_opv_numops; typedef (*PFI)(); /* the standard Pointer to a Function returning an Int */ /* * A miscellaneous routine. * A generic "default" routine that just returns an error. */ int vn_default_error() { return (EOPNOTSUPP); } /* * vfs_init.c * * Allocate and fill in operations vectors. * * An undocumented feature of this approach to defining operations is that * there can be multiple entries in vfs_opv_descs for the same operations * vector. This allows third parties to extend the set of operations * supported by another layer in a binary compatibile way. For example, * assume that NFS needed to be modified to support Ficus. NFS has an entry * (probably nfs_vnopdeop_decls) declaring all the operations NFS supports by * default. Ficus could add another entry (ficus_nfs_vnodeop_decl_entensions) * listing those new operations Ficus adds to NFS, all without modifying the * NFS code. (Of couse, the OTW NFS protocol still needs to be munged, but * that is a(whole)nother story.) This is a feature. */ void vfs_opv_init() { int i, j, k; int (***opv_desc_vector_p)(void *); int (**opv_desc_vector)(void *); struct vnodeopv_entry_desc *opve_descp; /* * Allocate the dynamic vectors and fill them in. */ for (i=0; vfs_opv_descs[i]; i++) { opv_desc_vector_p = vfs_opv_descs[i]->opv_desc_vector_p; /* * Allocate and init the vector, if it needs it. * Also handle backwards compatibility. */ if (*opv_desc_vector_p == NULL) { MALLOC(*opv_desc_vector_p, PFI*, vfs_opv_numops*sizeof(PFI), M_TEMP, M_WAITOK); bzero (*opv_desc_vector_p, vfs_opv_numops*sizeof(PFI)); DODEBUG(printf("vector at %x allocated\n", opv_desc_vector_p)); } opv_desc_vector = *opv_desc_vector_p; for (j=0; vfs_opv_descs[i]->opv_desc_ops[j].opve_op; j++) { opve_descp = &(vfs_opv_descs[i]->opv_desc_ops[j]); /* * Sanity check: is this operation listed * in the list of operations? We check this * by seeing if its offest is zero. Since * the default routine should always be listed * first, it should be the only one with a zero * offset. Any other operation with a zero * offset is probably not listed in * vfs_op_descs, and so is probably an error. * * A panic here means the layer programmer * has committed the all-too common bug * of adding a new operation to the layer's * list of vnode operations but * not adding the operation to the system-wide * list of supported operations. */ if (opve_descp->opve_op->vdesc_offset == 0 && opve_descp->opve_op->vdesc_offset != VOFFSET(vop_default)) { printf("operation %s not listed in %s.\n", opve_descp->opve_op->vdesc_name, "vfs_op_descs"); panic ("vfs_opv_init: bad operation"); } /* * Fill in this entry. */ opv_desc_vector[opve_descp->opve_op->vdesc_offset] = opve_descp->opve_impl; } } /* * Finally, go back and replace unfilled routines * with their default. (Sigh, an O(n^3) algorithm. I * could make it better, but that'd be work, and n is small.) */ for (i = 0; vfs_opv_descs[i]; i++) { opv_desc_vector = *(vfs_opv_descs[i]->opv_desc_vector_p); /* * Force every operations vector to have a default routine. */ if (opv_desc_vector[VOFFSET(vop_default)]==NULL) { panic("vfs_opv_init: operation vector without default routine."); } for (k = 0; k<vfs_opv_numops; k++) if (opv_desc_vector[k] == NULL) opv_desc_vector[k] = opv_desc_vector[VOFFSET(vop_default)]; } } /* * Initialize known vnode operations vectors. */ void vfs_op_init() { int i; DODEBUG(printf("Vnode_interface_init.\n")); /* * Set all vnode vectors to a well known value. */ for (i = 0; vfs_opv_descs[i]; i++) *(vfs_opv_descs[i]->opv_desc_vector_p) = NULL; /* * Figure out how many ops there are by counting the table, * and assign each its offset. */ for (vfs_opv_numops = 0, i = 0; vfs_op_descs[i]; i++) { vfs_op_descs[i]->vdesc_offset = vfs_opv_numops; vfs_opv_numops++; } DODEBUG(printf ("vfs_opv_numops=%d\n", vfs_opv_numops)); } /* * Routines having to do with the management of the vnode table. */ extern struct vnodeops dead_vnodeops; extern struct vnodeops spec_vnodeops; struct vattr va_null; /* * Initialize the vnode structures and initialize each file system type. */ vfsinit() { struct vfsconf *vfsp; int i, maxtypenum; /* * Initialize the "console user" for access purposes: */ console_user = (uid_t)0; /* * Initialize the vnode table */ vntblinit(); /* * Initialize the filesystem event mechanism. */ vfs_event_init(); /* * Initialize the vnode name cache */ nchinit(); /* * Build vnode operation vectors. */ vfs_op_init(); vfs_opv_init(); /* finish the job */ /* * Initialize each file system type in the static list, * until the first NULL ->vfs_vfsops is encountered. */ vattr_null(&va_null); numused_vfsslots = maxtypenum = 0; for (vfsp = vfsconf, i = 0; i < maxvfsconf; i++, vfsp++) { if (vfsp->vfc_vfsops == (struct vfsops *)0) break; if (i) vfsconf[i-1].vfc_next = vfsp; if (maxtypenum <= vfsp->vfc_typenum) maxtypenum = vfsp->vfc_typenum + 1; (*vfsp->vfc_vfsops->vfs_init)(vfsp); numused_vfsslots++; } /* next vfc_typenum to be used */ maxvfsconf = maxtypenum; } /* * Name: vfsconf_add * * Description: Add a filesystem to the vfsconf list at the first * unused slot. If no slots are available, return an * error. * * Parameter: nvfsp vfsconf for VFS to add * * Returns: 0 Success * -1 Failure * * Notes: The vfsconf should be treated as a linked list by * all external references, as the implementation is * expected to change in the future. The linkage is * through ->vfc_next, and the list is NULL terminated. * * Warning: This code assumes that vfsconf[0] is non-empty. */ int vfsconf_add(struct vfsconf *nvfsp) { int slot; struct vfsconf *slotp; if (nvfsp == NULL) /* overkill */ return (-1); /* * Find the next empty slot; we recognize an empty slot by a * NULL-valued ->vfc_vfsops, so if we delete a VFS, we must * ensure we set the entry back to NULL. */ for (slot = 0; slot < maxvfsslots; slot++) { if (vfsconf[slot].vfc_vfsops == NULL) break; } if (slot == maxvfsslots) { /* out of static slots; allocate one instead */ MALLOC(slotp, struct vfsconf *, sizeof(struct vfsconf), M_TEMP, M_WAITOK); } else { slotp = &vfsconf[slot]; } /* * Replace the contents of the next empty slot with the contents * of the provided nvfsp. * * Note; Takes advantage of the fact that 'slot' was left * with the value of 'maxvfslots' in the allocation case. */ bcopy(nvfsp, slotp, sizeof(struct vfsconf)); if (slot != 0) { slotp->vfc_next = vfsconf[slot - 1].vfc_next; vfsconf[slot - 1].vfc_next = slotp; } else { slotp->vfc_next = NULL; } numused_vfsslots++; /* * Call through the ->vfs_init(); use slotp instead of nvfsp, * so that if the FS cares where it's instance record is, it * can find it later. * * XXX All code that calls ->vfs_init treats it as if it * XXX returns a "void', and can never fail. */ if (nvfsp->vfc_vfsops->vfs_init) (*nvfsp->vfc_vfsops->vfs_init)(slotp); return(0); } /* * Name: vfsconf_del * * Description: Remove a filesystem from the vfsconf list by name. * If no such filesystem exists, return an error. * * Parameter: fs_name name of VFS to remove * * Returns: 0 Success * -1 Failure * * Notes: Hopefully all filesystems have unique names. */ int vfsconf_del(char * fs_name) { struct vfsconf **vcpp; struct vfsconf *vcdelp; /* * Traverse the list looking for fs_name; if found, *vcpp * will contain the address of the pointer to the entry to * be removed. */ for( vcpp = &vfsconf; *vcpp; vcpp = &(*vcpp)->vfc_next) { if (strcmp( (*vcpp)->vfc_name, fs_name) == 0) break; } if (*vcpp == NULL) { /* XXX need real error code for entry not found */ return(-1); } /* Unlink entry */ vcdelp = *vcpp; *vcpp = (*vcpp)->vfc_next; /* * Is this an entry from our static table? We find out by * seeing if the pointer to the object to be deleted places * the object in the address space containing the table (or not). */ if (vcdelp >= vfsconf && vcdelp < (vfsconf + maxvfsslots)) { /* Y */ /* Mark as empty for vfscon_add() */ bzero(vcdelp, sizeof(struct vfsconf)); numused_vfsslots--; } else { /* N */ /* * This entry was dynamically allocated; we must free it; * we would prefer to have just linked the caller's * vfsconf onto our list, but it may not be persistent * because of the previous (copying) implementation. */ FREE(vcdelp, M_TEMP); } return(0); }