Annotation of sys/kern/vfs_init.c, Revision 1.1.1.1
1.1 nbrk 1: /* $OpenBSD: vfs_init.c,v 1.19 2007/05/29 16:25:07 thib Exp $ */
2: /* $NetBSD: vfs_init.c,v 1.6 1996/02/09 19:00:58 christos Exp $ */
3:
4: /*
5: * Copyright (c) 1989, 1993
6: * The Regents of the University of California. All rights reserved.
7: *
8: * This code is derived from software contributed
9: * to Berkeley by John Heidemann of the UCLA Ficus project.
10: *
11: * Source: * @(#)i405_init.c 2.10 92/04/27 UCLA Ficus project
12: *
13: * Redistribution and use in source and binary forms, with or without
14: * modification, are permitted provided that the following conditions
15: * are met:
16: * 1. Redistributions of source code must retain the above copyright
17: * notice, this list of conditions and the following disclaimer.
18: * 2. Redistributions in binary form must reproduce the above copyright
19: * notice, this list of conditions and the following disclaimer in the
20: * documentation and/or other materials provided with the distribution.
21: * 3. Neither the name of the University nor the names of its contributors
22: * may be used to endorse or promote products derived from this software
23: * without specific prior written permission.
24: *
25: * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26: * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27: * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28: * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29: * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30: * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31: * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32: * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33: * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34: * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35: * SUCH DAMAGE.
36: *
37: * @(#)vfs_init.c 8.3 (Berkeley) 1/4/94
38: */
39:
40: #include <sys/param.h>
41: #include <sys/mount.h>
42: #include <sys/time.h>
43: #include <sys/vnode.h>
44: #include <sys/stat.h>
45: #include <sys/namei.h>
46: #include <sys/ucred.h>
47: #include <sys/buf.h>
48: #include <sys/errno.h>
49: #include <sys/malloc.h>
50: #include <sys/pool.h>
51: #include <sys/systm.h>
52:
53: /*
54: * Sigh, such primitive tools are these...
55: */
56: #if 0
57: #define DODEBUG(A) A
58: #else
59: #define DODEBUG(A)
60: #endif
61:
62: extern struct vnodeopv_desc *vfs_opv_descs[];
63: /* a list of lists of vnodeops defns */
64: extern struct vnodeop_desc *vfs_op_descs[];
65: /* and the operations they perform */
66: /*
67: * This code doesn't work if the defn is **vnodop_defns with cc.
68: * The problem is because of the compiler sometimes putting in an
69: * extra level of indirection for arrays. It's an interesting
70: * "feature" of C.
71: */
72: int vfs_opv_numops;
73:
74: typedef int (*PFI)(void *);
75:
76: /*
77: * A miscellaneous routine.
78: * A generic "default" routine that just returns an error.
79: */
80: /*ARGSUSED*/
81: int
82: vn_default_error(void *v)
83: {
84:
85: return (EOPNOTSUPP);
86: }
87:
88: /*
89: * vfs_init.c
90: *
91: * Allocate and fill in operations vectors.
92: *
93: * An undocumented feature of this approach to defining operations is that
94: * there can be multiple entries in vfs_opv_descs for the same operations
95: * vector. This allows third parties to extend the set of operations
96: * supported by another layer in a binary compatibile way. For example,
97: * assume that NFS needed to be modified to support Ficus. NFS has an entry
98: * (probably nfs_vnopdeop_decls) declaring all the operations NFS supports by
99: * default. Ficus could add another entry (ficus_nfs_vnodeop_decl_entensions)
100: * listing those new operations Ficus adds to NFS, all without modifying the
101: * NFS code. (Of couse, the OTW NFS protocol still needs to be munged, but
102: * that is a(whole)nother story.) This is a feature.
103: */
104:
105: /*
106: * Allocate and init the vector, if it needs it.
107: * Also handle backwards compatibility.
108: */
109: void
110: vfs_opv_init_explicit(struct vnodeopv_desc *vfs_opv_desc)
111: {
112: int (**opv_desc_vector)(void *);
113: struct vnodeopv_entry_desc *opve_descp;
114:
115: opv_desc_vector = *(vfs_opv_desc->opv_desc_vector_p);
116:
117: if (opv_desc_vector == NULL) {
118: /* XXX - shouldn't be M_VNODE */
119: opv_desc_vector = malloc(vfs_opv_numops * sizeof(PFI),
120: M_VNODE, M_WAITOK);
121: bzero(opv_desc_vector, vfs_opv_numops * sizeof(PFI));
122: *(vfs_opv_desc->opv_desc_vector_p) = opv_desc_vector;
123: DODEBUG(printf("vector at %p allocated\n",
124: opv_desc_vector));
125: }
126:
127: for (opve_descp = vfs_opv_desc->opv_desc_ops;
128: opve_descp->opve_op; opve_descp++) {
129: /*
130: * Sanity check: is this operation listed
131: * in the list of operations? We check this
132: * by seeing if its offset is zero. Since
133: * the default routine should always be listed
134: * first, it should be the only one with a zero
135: * offset. Any other operation with a zero
136: * offset is probably not listed in
137: * vfs_op_descs, and so is probably an error.
138: *
139: * A panic here means the layer programmer
140: * has committed the all-too common bug
141: * of adding a new operation to the layer's
142: * list of vnode operations but
143: * not adding the operation to the system-wide
144: * list of supported operations.
145: */
146: if (opve_descp->opve_op->vdesc_offset == 0 &&
147: opve_descp->opve_op->vdesc_offset != VOFFSET(vop_default)) {
148: printf("operation %s not listed in %s.\n",
149: opve_descp->opve_op->vdesc_name, "vfs_op_descs");
150: panic ("vfs_opv_init: bad operation");
151: }
152:
153: /*
154: * Fill in this entry.
155: */
156: opv_desc_vector[opve_descp->opve_op->vdesc_offset] =
157: opve_descp->opve_impl;
158: }
159: }
160:
161: void
162: vfs_opv_init_default(struct vnodeopv_desc *vfs_opv_desc)
163: {
164: int j;
165: int (**opv_desc_vector)(void *);
166:
167: opv_desc_vector = *(vfs_opv_desc->opv_desc_vector_p);
168:
169: /*
170: * Force every operations vector to have a default routine.
171: */
172: if (opv_desc_vector[VOFFSET(vop_default)] == NULL)
173: panic("vfs_opv_init: operation vector without default routine.");
174:
175: for (j = 0; j < vfs_opv_numops; j++)
176: if (opv_desc_vector[j] == NULL)
177: opv_desc_vector[j] =
178: opv_desc_vector[VOFFSET(vop_default)];
179: }
180:
181: void
182: vfs_opv_init(void)
183: {
184: int i;
185:
186: /*
187: * Allocate the dynamic vectors and fill them in.
188: */
189: for (i = 0; vfs_opv_descs[i]; i++)
190: vfs_opv_init_explicit(vfs_opv_descs[i]);
191:
192: /*
193: * Finally, go back and replace unfilled routines
194: * with their default.
195: */
196: for (i = 0; vfs_opv_descs[i]; i++)
197: vfs_opv_init_default(vfs_opv_descs[i]);
198: }
199:
200: /*
201: * Initialize known vnode operations vectors.
202: */
203: void
204: vfs_op_init(void)
205: {
206: int i;
207:
208: DODEBUG(printf("Vnode_interface_init.\n"));
209: /*
210: * Set all vnode vectors to a well known value.
211: */
212: for (i = 0; vfs_opv_descs[i]; i++)
213: *(vfs_opv_descs[i]->opv_desc_vector_p) = NULL;
214: /*
215: * Figure out how many ops there are by counting the table,
216: * and assign each its offset.
217: */
218: for (vfs_opv_numops = 0, i = 0; vfs_op_descs[i]; i++) {
219: vfs_op_descs[i]->vdesc_offset = vfs_opv_numops;
220: vfs_opv_numops++;
221: }
222: DODEBUG(printf ("vfs_opv_numops=%d\n", vfs_opv_numops));
223: }
224:
225: /*
226: * Routines having to do with the management of the vnode table.
227: */
228: struct pool namei_pool;
229:
230: /*
231: * Initialize the vnode structures and initialize each file system type.
232: */
233: void
234: vfsinit(void)
235: {
236: int i;
237: struct vfsconf *vfsconflist;
238: int vfsconflistlen;
239:
240: pool_init(&namei_pool, MAXPATHLEN, 0, 0, 0, "namei",
241: &pool_allocator_nointr);
242:
243: /*
244: * Initialize the vnode table
245: */
246: vntblinit();
247: /*
248: * Initialize the vnode name cache
249: */
250: nchinit();
251: /*
252: * Build vnode operation vectors.
253: */
254: vfs_op_init();
255: vfs_opv_init(); /* finish the job */
256:
257: /*
258: * Stop using vfsconf and maxvfsconf as a temporary storage,
259: * set them to their correct values now.
260: */
261: vfsconflist = vfsconf;
262: vfsconflistlen = maxvfsconf;
263: vfsconf = NULL;
264: maxvfsconf = 0;
265:
266: for (i = 0; i < vfsconflistlen; i++)
267: vfs_register(&vfsconflist[i]);
268: }
CVSweb
![[BACK]](/icons/back.gif){kind=icon}
Return to vfs_init.c CVS log ![[TXT]](/icons/text.gif){kind=icon}
![[DIR]](/icons/dir.gif){kind=icon}
Up to [local] / sys / kern