1/*-
2 * Copyright (c) 2001 Dag-Erling Co�dan Sm�rgrav
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer
10 *    in this position and unchanged.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 * 3. The name of the author may not be used to endorse or promote products
15 *    derived from this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29#include <sys/cdefs.h>
30__FBSDID("$FreeBSD$");
31
32#include "opt_pseudofs.h"
33
34#include <sys/param.h>
35#include <sys/kernel.h>
36#include <sys/systm.h>
37#include <sys/limits.h>
38#include <sys/lock.h>
39#include <sys/malloc.h>
40#include <sys/mutex.h>
41#include <sys/proc.h>
42#include <sys/sysctl.h>
43#include <sys/systm.h>
44
45#include <fs/pseudofs/pseudofs.h>
46#include <fs/pseudofs/pseudofs_internal.h>
47
48/*
49 * Initialize fileno bitmap
50 */
51void
52pfs_fileno_init(struct pfs_info *pi)
53{
54
55	mtx_assert(&Giant, MA_OWNED);
56	mtx_init(&pi->pi_mutex, "pfs_fileno", NULL, MTX_DEF);
57	pi->pi_unrhdr = new_unrhdr(3, INT_MAX / NO_PID, &pi->pi_mutex);
58}
59
60/*
61 * Tear down fileno bitmap
62 */
63void
64pfs_fileno_uninit(struct pfs_info *pi)
65{
66
67	mtx_assert(&Giant, MA_OWNED);
68	delete_unrhdr(pi->pi_unrhdr);
69	pi->pi_unrhdr = NULL;
70	mtx_destroy(&pi->pi_mutex);
71}
72
73/*
74 * Allocate a file number
75 */
76void
77pfs_fileno_alloc(struct pfs_node *pn)
78{
79
80	if (pn->pn_parent)
81		PFS_TRACE(("%s/%s", pn->pn_parent->pn_name, pn->pn_name));
82	else
83		PFS_TRACE(("%s", pn->pn_name));
84	pfs_assert_not_owned(pn);
85
86	switch (pn->pn_type) {
87	case pfstype_root:
88		/* root must always be 2 */
89		pn->pn_fileno = 2;
90		break;
91	case pfstype_dir:
92	case pfstype_file:
93	case pfstype_symlink:
94	case pfstype_procdir:
95		pn->pn_fileno = alloc_unr(pn->pn_info->pi_unrhdr);
96		break;
97	case pfstype_this:
98		KASSERT(pn->pn_parent != NULL,
99		    ("%s(): pfstype_this node has no parent", __func__));
100		pn->pn_fileno = pn->pn_parent->pn_fileno;
101		break;
102	case pfstype_parent:
103		KASSERT(pn->pn_parent != NULL,
104		    ("%s(): pfstype_parent node has no parent", __func__));
105		if (pn->pn_parent->pn_type == pfstype_root) {
106			pn->pn_fileno = pn->pn_parent->pn_fileno;
107			break;
108		}
109		KASSERT(pn->pn_parent->pn_parent != NULL,
110		    ("%s(): pfstype_parent node has no grandparent", __func__));
111		pn->pn_fileno = pn->pn_parent->pn_parent->pn_fileno;
112		break;
113	case pfstype_none:
114		KASSERT(0,
115		    ("%s(): pfstype_none node", __func__));
116		break;
117	}
118
119#if 0
120	printf("%s(): %s: ", __func__, pn->pn_info->pi_name);
121	if (pn->pn_parent) {
122		if (pn->pn_parent->pn_parent) {
123			printf("%s/", pn->pn_parent->pn_parent->pn_name);
124		}
125		printf("%s/", pn->pn_parent->pn_name);
126	}
127	printf("%s -> %d\n", pn->pn_name, pn->pn_fileno);
128#endif
129}
130
131/*
132 * Release a file number
133 */
134void
135pfs_fileno_free(struct pfs_node *pn)
136{
137
138	pfs_assert_not_owned(pn);
139
140	switch (pn->pn_type) {
141	case pfstype_root:
142		/* not allocated from unrhdr */
143		return;
144	case pfstype_dir:
145	case pfstype_file:
146	case pfstype_symlink:
147	case pfstype_procdir:
148		free_unr(pn->pn_info->pi_unrhdr, pn->pn_fileno);
149		break;
150	case pfstype_this:
151	case pfstype_parent:
152		/* ignore these, as they don't "own" their file number */
153		break;
154	case pfstype_none:
155		KASSERT(0,
156		    ("pfs_fileno_free() called for pfstype_none node"));
157		break;
158	}
159}
160