File: /usr/src/linux/drivers/char/ftape/zftape/zftape-buffers.c
1 /*
2 * Copyright (C) 1995-1997 Claus-Justus Heine.
3
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU General Public License as published by
6 the Free Software Foundation; either version 2, or (at your option)
7 any later version.
8
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU General Public License for more details.
13
14 You should have received a copy of the GNU General Public License
15 along with this program; see the file COPYING. If not, write to
16 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
17
18 *
19 * $Source: /homes/cvs/ftape-stacked/ftape/zftape/zftape-buffers.c,v $
20 * $Revision: 1.2 $
21 * $Date: 1997/10/05 19:18:59 $
22 *
23 * This file contains the dynamic buffer allocation routines
24 * of zftape
25 */
26
27 #include <linux/errno.h>
28 #include <linux/mm.h>
29 #include <linux/slab.h>
30 #include <asm/segment.h>
31
32 #include <linux/zftape.h>
33
34 #if LINUX_VERSION_CODE >= KERNEL_VER(2,1,0)
35 #include <linux/vmalloc.h>
36 #endif
37
38 #include "../zftape/zftape-init.h"
39 #include "../zftape/zftape-eof.h"
40 #include "../zftape/zftape-ctl.h"
41 #include "../zftape/zftape-write.h"
42 #include "../zftape/zftape-read.h"
43 #include "../zftape/zftape-rw.h"
44 #include "../zftape/zftape-vtbl.h"
45
46 /* global variables
47 */
48
49 /* local varibales
50 */
51 static unsigned int used_memory;
52 static unsigned int peak_memory;
53
54 void zft_memory_stats(void)
55 {
56 TRACE_FUN(ft_t_flow);
57
58 TRACE(ft_t_noise, "Memory usage (vmalloc allocations):\n"
59 KERN_INFO "total allocated: %d\n"
60 KERN_INFO "peak allocation: %d",
61 used_memory, peak_memory);
62 peak_memory = used_memory;
63 TRACE_EXIT;
64 }
65
66 int zft_vcalloc_once(void *new, size_t size)
67 {
68 TRACE_FUN(ft_t_flow);
69 if (zft_vmalloc_once(new, size) < 0) {
70 TRACE_EXIT -ENOMEM;
71 }
72 memset(*(void **)new, '\0', size);
73 TRACE_EXIT 0;
74 }
75 int zft_vmalloc_once(void *new, size_t size)
76 {
77 TRACE_FUN(ft_t_flow);
78
79 if (*(void **)new != NULL || size == 0) {
80 TRACE_EXIT 0;
81 }
82 if ((*(void **)new = vmalloc(size)) == NULL) {
83 TRACE_EXIT -ENOMEM;
84 }
85 used_memory += size;
86 if (peak_memory < used_memory) {
87 peak_memory = used_memory;
88 }
89 TRACE_ABORT(0, ft_t_noise,
90 "allocated buffer @ %p, %d bytes", *(void **)new, size);
91 }
92 int zft_vcalloc_always(void *new, size_t size)
93 {
94 TRACE_FUN(ft_t_flow);
95
96 zft_vfree(new, size);
97 TRACE_EXIT zft_vcalloc_once(new, size);
98 }
99 int zft_vmalloc_always(void *new, size_t size)
100 {
101 TRACE_FUN(ft_t_flow);
102
103 zft_vfree(new, size);
104 TRACE_EXIT zft_vmalloc_once(new, size);
105 }
106 void zft_vfree(void *old, size_t size)
107 {
108 TRACE_FUN(ft_t_flow);
109
110 if (*(void **)old) {
111 vfree(*(void **)old);
112 used_memory -= size;
113 TRACE(ft_t_noise, "released buffer @ %p, %d bytes",
114 *(void **)old, size);
115 *(void **)old = NULL;
116 }
117 TRACE_EXIT;
118 }
119
120 void *zft_kmalloc(size_t size)
121 {
122 void *new;
123
124 while ((new = kmalloc(size, GFP_KERNEL)) == NULL) {
125 current->state = TASK_INTERRUPTIBLE;
126 schedule_timeout(HZ/10);
127 }
128 memset(new, 0, size);
129 used_memory += size;
130 if (peak_memory < used_memory) {
131 peak_memory = used_memory;
132 }
133 return new;
134 }
135
136 void zft_kfree(void *old, size_t size)
137 {
138 kfree(old);
139 used_memory -= size;
140 }
141
142 /* there are some more buffers that are allocated on demand.
143 * cleanup_module() calles this function to be sure to have released
144 * them
145 */
146 void zft_uninit_mem(void)
147 {
148 TRACE_FUN(ft_t_flow);
149
150 zft_vfree(&zft_hseg_buf, FT_SEGMENT_SIZE);
151 zft_vfree(&zft_deblock_buf, FT_SEGMENT_SIZE); zft_deblock_segment = -1;
152 zft_free_vtbl();
153 if (zft_cmpr_lock(0 /* don't load */) == 0) {
154 (*zft_cmpr_ops->cleanup)();
155 (*zft_cmpr_ops->reset)(); /* unlock it again */
156 }
157 zft_memory_stats();
158 TRACE_EXIT;
159 }
160