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 
zft_memory_stats(void)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 
zft_vcalloc_once(void * new,size_t size)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 }
zft_vmalloc_once(void * new,size_t size)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 }
zft_vcalloc_always(void * new,size_t size)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 }
zft_vmalloc_always(void * new,size_t size)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 }
zft_vfree(void * old,size_t size)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 
zft_kmalloc(size_t size)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 
zft_kfree(void * old,size_t size)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  */
zft_uninit_mem(void)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