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 *
| 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 * $FreeBSD: head/sys/fs/pseudofs/pseudofs_fileno.c 97940 2002-06-06 16:59:24Z des $
| 28 * $FreeBSD: head/sys/fs/pseudofs/pseudofs_fileno.c 109623 2003-01-21 08:56:16Z alfred $
|
29 */
30
31#include <sys/param.h>
32#include <sys/kernel.h>
33#include <sys/systm.h>
34#include <sys/lock.h>
35#include <sys/malloc.h>
36#include <sys/mutex.h>
37#include <sys/sysctl.h>
38
39#include <machine/limits.h>
40
41#include <fs/pseudofs/pseudofs.h>
42#include <fs/pseudofs/pseudofs_internal.h>
43
44static MALLOC_DEFINE(M_PFSFILENO, "pfs_fileno", "pseudofs fileno bitmap");
45
46static struct mtx pfs_fileno_mutex;
47
48#define PFS_BITMAP_SIZE 4096
49#define PFS_SLOT_BITS (int)(sizeof(unsigned int) * CHAR_BIT)
50#define PFS_BITMAP_BITS (PFS_BITMAP_SIZE * PFS_SLOT_BITS)
51struct pfs_bitmap {
52 u_int32_t pb_offset;
53 int pb_used;
54 unsigned int pb_bitmap[PFS_BITMAP_SIZE];
55 struct pfs_bitmap *pb_next;
56};
57
58/*
59 * Initialization
60 */
61void
62pfs_fileno_load(void)
63{
64 mtx_init(&pfs_fileno_mutex, "pseudofs_fileno", NULL, MTX_DEF);
65}
66
67/*
68 * Teardown
69 */
70void
71pfs_fileno_unload(void)
72{
73 mtx_destroy(&pfs_fileno_mutex);
74}
75
76/*
77 * Initialize fileno bitmap
78 */
79void
80pfs_fileno_init(struct pfs_info *pi)
81{
82 struct pfs_bitmap *pb;
83
84 MALLOC(pb, struct pfs_bitmap *, sizeof *pb,
| 29 */
30
31#include <sys/param.h>
32#include <sys/kernel.h>
33#include <sys/systm.h>
34#include <sys/lock.h>
35#include <sys/malloc.h>
36#include <sys/mutex.h>
37#include <sys/sysctl.h>
38
39#include <machine/limits.h>
40
41#include <fs/pseudofs/pseudofs.h>
42#include <fs/pseudofs/pseudofs_internal.h>
43
44static MALLOC_DEFINE(M_PFSFILENO, "pfs_fileno", "pseudofs fileno bitmap");
45
46static struct mtx pfs_fileno_mutex;
47
48#define PFS_BITMAP_SIZE 4096
49#define PFS_SLOT_BITS (int)(sizeof(unsigned int) * CHAR_BIT)
50#define PFS_BITMAP_BITS (PFS_BITMAP_SIZE * PFS_SLOT_BITS)
51struct pfs_bitmap {
52 u_int32_t pb_offset;
53 int pb_used;
54 unsigned int pb_bitmap[PFS_BITMAP_SIZE];
55 struct pfs_bitmap *pb_next;
56};
57
58/*
59 * Initialization
60 */
61void
62pfs_fileno_load(void)
63{
64 mtx_init(&pfs_fileno_mutex, "pseudofs_fileno", NULL, MTX_DEF);
65}
66
67/*
68 * Teardown
69 */
70void
71pfs_fileno_unload(void)
72{
73 mtx_destroy(&pfs_fileno_mutex);
74}
75
76/*
77 * Initialize fileno bitmap
78 */
79void
80pfs_fileno_init(struct pfs_info *pi)
81{
82 struct pfs_bitmap *pb;
83
84 MALLOC(pb, struct pfs_bitmap *, sizeof *pb,
|
85 M_PFSFILENO, M_WAITOK|M_ZERO);
| 85 M_PFSFILENO, M_ZERO);
|
86
87 mtx_lock(&pi->pi_mutex);
88
89 pb->pb_bitmap[0] = 07;
90 pb->pb_used = 3;
91 pi->pi_bitmap = pb;
92 pi->pi_root->pn_fileno = 2;
93
94 mtx_unlock(&pi->pi_mutex);
95}
96
97/*
98 * Tear down fileno bitmap
99 */
100void
101pfs_fileno_uninit(struct pfs_info *pi)
102{
103 struct pfs_bitmap *pb, *npb;
104 int used;
105
106 mtx_lock(&pi->pi_mutex);
107
108 pb = pi->pi_bitmap;
109 pi->pi_bitmap = NULL;
110
111 mtx_unlock(&pi->pi_mutex);
112
113 for (used = 0; pb; pb = npb) {
114 npb = pb->pb_next;
115 used += pb->pb_used;
116 FREE(pb, M_PFSFILENO);
117 }
118#if 0
119 /* we currently don't reclaim filenos */
120 if (used > 2)
121 printf("WARNING: %d file numbers still in use\n", used);
122#endif
123}
124
125/*
126 * Get the next available file number
127 */
128static u_int32_t
129pfs_get_fileno(struct pfs_info *pi)
130{
131 struct pfs_bitmap *pb, *ppb;
132 u_int32_t fileno;
133 unsigned int *p;
134 int i;
135
136 mtx_lock(&pi->pi_mutex);
137
138 /* look for the first page with free bits */
139 for (ppb = NULL, pb = pi->pi_bitmap; pb; ppb = pb, pb = pb->pb_next)
140 if (pb->pb_used != PFS_BITMAP_BITS)
141 break;
142
143 /* out of pages? */
144 if (pb == NULL) {
145 mtx_unlock(&pi->pi_mutex);
146 MALLOC(pb, struct pfs_bitmap *, sizeof *pb,
| 86
87 mtx_lock(&pi->pi_mutex);
88
89 pb->pb_bitmap[0] = 07;
90 pb->pb_used = 3;
91 pi->pi_bitmap = pb;
92 pi->pi_root->pn_fileno = 2;
93
94 mtx_unlock(&pi->pi_mutex);
95}
96
97/*
98 * Tear down fileno bitmap
99 */
100void
101pfs_fileno_uninit(struct pfs_info *pi)
102{
103 struct pfs_bitmap *pb, *npb;
104 int used;
105
106 mtx_lock(&pi->pi_mutex);
107
108 pb = pi->pi_bitmap;
109 pi->pi_bitmap = NULL;
110
111 mtx_unlock(&pi->pi_mutex);
112
113 for (used = 0; pb; pb = npb) {
114 npb = pb->pb_next;
115 used += pb->pb_used;
116 FREE(pb, M_PFSFILENO);
117 }
118#if 0
119 /* we currently don't reclaim filenos */
120 if (used > 2)
121 printf("WARNING: %d file numbers still in use\n", used);
122#endif
123}
124
125/*
126 * Get the next available file number
127 */
128static u_int32_t
129pfs_get_fileno(struct pfs_info *pi)
130{
131 struct pfs_bitmap *pb, *ppb;
132 u_int32_t fileno;
133 unsigned int *p;
134 int i;
135
136 mtx_lock(&pi->pi_mutex);
137
138 /* look for the first page with free bits */
139 for (ppb = NULL, pb = pi->pi_bitmap; pb; ppb = pb, pb = pb->pb_next)
140 if (pb->pb_used != PFS_BITMAP_BITS)
141 break;
142
143 /* out of pages? */
144 if (pb == NULL) {
145 mtx_unlock(&pi->pi_mutex);
146 MALLOC(pb, struct pfs_bitmap *, sizeof *pb,
|
147 M_PFSFILENO, M_WAITOK|M_ZERO);
| 147 M_PFSFILENO, M_ZERO);
|
148 mtx_lock(&pi->pi_mutex);
149 /* protect against possible race */
150 while (ppb->pb_next)
151 ppb = ppb->pb_next;
152 pb->pb_offset = ppb->pb_offset + PFS_BITMAP_BITS;
153 ppb->pb_next = pb;
154 }
155
156 /* find the first free slot */
157 for (i = 0; i < PFS_BITMAP_SIZE; ++i)
158 if (pb->pb_bitmap[i] != UINT_MAX)
159 break;
160
161 /* find the first available bit and flip it */
162 fileno = pb->pb_offset + i * PFS_SLOT_BITS;
163 p = &pb->pb_bitmap[i];
164 for (i = 0; i < PFS_SLOT_BITS; ++i, ++fileno)
165 if ((*p & (unsigned int)(1 << i)) == 0)
166 break;
167 KASSERT(i < PFS_SLOT_BITS,
168 ("slot has free bits, yet doesn't"));
169 *p |= (unsigned int)(1 << i);
170 ++pb->pb_used;
171
172 mtx_unlock(&pi->pi_mutex);
173
174 return fileno;
175}
176
177/*
178 * Free a file number
179 */
180static void
181pfs_free_fileno(struct pfs_info *pi, u_int32_t fileno)
182{
183 struct pfs_bitmap *pb;
184 unsigned int *p;
185 int i;
186
187 mtx_lock(&pi->pi_mutex);
188
189 /* find the right page */
190 for (pb = pi->pi_bitmap;
191 pb && fileno >= PFS_BITMAP_BITS;
192 pb = pb->pb_next, fileno -= PFS_BITMAP_BITS)
193 /* nothing */ ;
194 KASSERT(pb,
195 ("fileno isn't in any bitmap"));
196
197 /* find the right bit in the right slot and flip it */
198 p = &pb->pb_bitmap[fileno / PFS_SLOT_BITS];
199 i = fileno % PFS_SLOT_BITS;
200 KASSERT(*p & (unsigned int)(1 << i),
201 ("fileno is already free"));
202 *p &= ~((unsigned int)(1 << i));
203 --pb->pb_used;
204
205 mtx_unlock(&pi->pi_mutex);
206 printf("pfs_free_fileno(): reclaimed %d\n", fileno);
207}
208
209/*
210 * Allocate a file number
211 */
212void
213pfs_fileno_alloc(struct pfs_info *pi, struct pfs_node *pn)
214{
215 /* make sure our parent has a file number */
216 if (pn->pn_parent && !pn->pn_parent->pn_fileno)
217 pfs_fileno_alloc(pi, pn->pn_parent);
218
219 switch (pn->pn_type) {
220 case pfstype_root:
221 case pfstype_dir:
222 case pfstype_file:
223 case pfstype_symlink:
224 case pfstype_procdir:
225 pn->pn_fileno = pfs_get_fileno(pi);
226 break;
227 case pfstype_this:
228 KASSERT(pn->pn_parent != NULL,
229 ("pfstype_this node has no parent"));
230 pn->pn_fileno = pn->pn_parent->pn_fileno;
231 break;
232 case pfstype_parent:
233 KASSERT(pn->pn_parent != NULL,
234 ("pfstype_parent node has no parent"));
235 if (pn->pn_parent == pi->pi_root) {
236 pn->pn_fileno = pn->pn_parent->pn_fileno;
237 break;
238 }
239 KASSERT(pn->pn_parent->pn_parent != NULL,
240 ("pfstype_parent node has no grandparent"));
241 pn->pn_fileno = pn->pn_parent->pn_parent->pn_fileno;
242 break;
243 case pfstype_none:
244 KASSERT(0,
245 ("pfs_fileno_alloc() called for pfstype_none node"));
246 break;
247 }
248
249#if 0
250 printf("pfs_fileno_alloc(): %s: ", pi->pi_name);
251 if (pn->pn_parent) {
252 if (pn->pn_parent->pn_parent) {
253 printf("%s/", pn->pn_parent->pn_parent->pn_name);
254 }
255 printf("%s/", pn->pn_parent->pn_name);
256 }
257 printf("%s -> %d\n", pn->pn_name, pn->pn_fileno);
258#endif
259}
260
261/*
262 * Release a file number
263 */
264void
265pfs_fileno_free(struct pfs_info *pi, struct pfs_node *pn)
266{
267 switch (pn->pn_type) {
268 case pfstype_root:
269 case pfstype_dir:
270 case pfstype_file:
271 case pfstype_symlink:
272 case pfstype_procdir:
273 pfs_free_fileno(pi, pn->pn_fileno);
274 break;
275 case pfstype_this:
276 case pfstype_parent:
277 /* ignore these, as they don't "own" their file number */
278 break;
279 case pfstype_none:
280 KASSERT(0,
281 ("pfs_fileno_free() called for pfstype_none node"));
282 break;
283 }
284}
| 148 mtx_lock(&pi->pi_mutex);
149 /* protect against possible race */
150 while (ppb->pb_next)
151 ppb = ppb->pb_next;
152 pb->pb_offset = ppb->pb_offset + PFS_BITMAP_BITS;
153 ppb->pb_next = pb;
154 }
155
156 /* find the first free slot */
157 for (i = 0; i < PFS_BITMAP_SIZE; ++i)
158 if (pb->pb_bitmap[i] != UINT_MAX)
159 break;
160
161 /* find the first available bit and flip it */
162 fileno = pb->pb_offset + i * PFS_SLOT_BITS;
163 p = &pb->pb_bitmap[i];
164 for (i = 0; i < PFS_SLOT_BITS; ++i, ++fileno)
165 if ((*p & (unsigned int)(1 << i)) == 0)
166 break;
167 KASSERT(i < PFS_SLOT_BITS,
168 ("slot has free bits, yet doesn't"));
169 *p |= (unsigned int)(1 << i);
170 ++pb->pb_used;
171
172 mtx_unlock(&pi->pi_mutex);
173
174 return fileno;
175}
176
177/*
178 * Free a file number
179 */
180static void
181pfs_free_fileno(struct pfs_info *pi, u_int32_t fileno)
182{
183 struct pfs_bitmap *pb;
184 unsigned int *p;
185 int i;
186
187 mtx_lock(&pi->pi_mutex);
188
189 /* find the right page */
190 for (pb = pi->pi_bitmap;
191 pb && fileno >= PFS_BITMAP_BITS;
192 pb = pb->pb_next, fileno -= PFS_BITMAP_BITS)
193 /* nothing */ ;
194 KASSERT(pb,
195 ("fileno isn't in any bitmap"));
196
197 /* find the right bit in the right slot and flip it */
198 p = &pb->pb_bitmap[fileno / PFS_SLOT_BITS];
199 i = fileno % PFS_SLOT_BITS;
200 KASSERT(*p & (unsigned int)(1 << i),
201 ("fileno is already free"));
202 *p &= ~((unsigned int)(1 << i));
203 --pb->pb_used;
204
205 mtx_unlock(&pi->pi_mutex);
206 printf("pfs_free_fileno(): reclaimed %d\n", fileno);
207}
208
209/*
210 * Allocate a file number
211 */
212void
213pfs_fileno_alloc(struct pfs_info *pi, struct pfs_node *pn)
214{
215 /* make sure our parent has a file number */
216 if (pn->pn_parent && !pn->pn_parent->pn_fileno)
217 pfs_fileno_alloc(pi, pn->pn_parent);
218
219 switch (pn->pn_type) {
220 case pfstype_root:
221 case pfstype_dir:
222 case pfstype_file:
223 case pfstype_symlink:
224 case pfstype_procdir:
225 pn->pn_fileno = pfs_get_fileno(pi);
226 break;
227 case pfstype_this:
228 KASSERT(pn->pn_parent != NULL,
229 ("pfstype_this node has no parent"));
230 pn->pn_fileno = pn->pn_parent->pn_fileno;
231 break;
232 case pfstype_parent:
233 KASSERT(pn->pn_parent != NULL,
234 ("pfstype_parent node has no parent"));
235 if (pn->pn_parent == pi->pi_root) {
236 pn->pn_fileno = pn->pn_parent->pn_fileno;
237 break;
238 }
239 KASSERT(pn->pn_parent->pn_parent != NULL,
240 ("pfstype_parent node has no grandparent"));
241 pn->pn_fileno = pn->pn_parent->pn_parent->pn_fileno;
242 break;
243 case pfstype_none:
244 KASSERT(0,
245 ("pfs_fileno_alloc() called for pfstype_none node"));
246 break;
247 }
248
249#if 0
250 printf("pfs_fileno_alloc(): %s: ", pi->pi_name);
251 if (pn->pn_parent) {
252 if (pn->pn_parent->pn_parent) {
253 printf("%s/", pn->pn_parent->pn_parent->pn_name);
254 }
255 printf("%s/", pn->pn_parent->pn_name);
256 }
257 printf("%s -> %d\n", pn->pn_name, pn->pn_fileno);
258#endif
259}
260
261/*
262 * Release a file number
263 */
264void
265pfs_fileno_free(struct pfs_info *pi, struct pfs_node *pn)
266{
267 switch (pn->pn_type) {
268 case pfstype_root:
269 case pfstype_dir:
270 case pfstype_file:
271 case pfstype_symlink:
272 case pfstype_procdir:
273 pfs_free_fileno(pi, pn->pn_fileno);
274 break;
275 case pfstype_this:
276 case pfstype_parent:
277 /* ignore these, as they don't "own" their file number */
278 break;
279 case pfstype_none:
280 KASSERT(0,
281 ("pfs_fileno_free() called for pfstype_none node"));
282 break;
283 }
284}
|