1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
|
/*
*
* (C) COPYRIGHT 2008-2012 ARM Limited. All rights reserved.
*
* This program is free software and is provided to you under the terms of the
* GNU General Public License version 2 as published by the Free Software
* Foundation, and any use by you of this program is subject to the terms
* of such GNU licence.
*
* A copy of the licence is included with the program, and can also be obtained
* from Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
*
*/
#include <common/ump_kernel_descriptor_mapping.h>
#include <common/ump_kernel_priv.h>
#define MALI_PAD_INT(x) (((x) + (BITS_PER_LONG - 1)) & ~(BITS_PER_LONG - 1))
/**
* Allocate a descriptor table capable of holding 'count' mappings
* @param count Number of mappings in the table
* @return Pointer to a new table, NULL on error
*/
static umpp_descriptor_table * descriptor_table_alloc(unsigned int count);
/**
* Free a descriptor table
* @param table The table to free
*/
static void descriptor_table_free(umpp_descriptor_table * table);
umpp_descriptor_mapping * umpp_descriptor_mapping_create(unsigned int init_entries, unsigned int max_entries)
{
umpp_descriptor_mapping * map = kzalloc(sizeof(umpp_descriptor_mapping), GFP_KERNEL);
init_entries = MALI_PAD_INT(init_entries);
max_entries = MALI_PAD_INT(max_entries);
if (NULL != map)
{
map->table = descriptor_table_alloc(init_entries);
if (NULL != map->table)
{
init_rwsem( &map->lock);
set_bit(0, map->table->usage);
map->max_nr_mappings_allowed = max_entries;
map->current_nr_mappings = init_entries;
return map;
descriptor_table_free(map->table);
}
kfree(map);
}
return NULL;
}
void umpp_descriptor_mapping_destroy(umpp_descriptor_mapping * map)
{
UMP_ASSERT(NULL != map);
descriptor_table_free(map->table);
kfree(map);
}
unsigned int umpp_descriptor_mapping_allocate(umpp_descriptor_mapping * map, void * target)
{
int descriptor = 0;
UMP_ASSERT(NULL != map);
down_write( &map->lock);
descriptor = find_first_zero_bit(map->table->usage, map->current_nr_mappings);
if (descriptor == map->current_nr_mappings)
{
/* no free descriptor, try to expand the table */
umpp_descriptor_table * new_table;
umpp_descriptor_table * old_table = map->table;
int nr_mappings_new = map->current_nr_mappings + BITS_PER_LONG;
if (map->current_nr_mappings >= map->max_nr_mappings_allowed)
{
descriptor = 0;
goto unlock_and_exit;
}
new_table = descriptor_table_alloc(nr_mappings_new);
if (NULL == new_table)
{
descriptor = 0;
goto unlock_and_exit;
}
memcpy(new_table->usage, old_table->usage, (sizeof(unsigned long)*map->current_nr_mappings) / BITS_PER_LONG);
memcpy(new_table->mappings, old_table->mappings, map->current_nr_mappings * sizeof(void*));
map->table = new_table;
map->current_nr_mappings = nr_mappings_new;
descriptor_table_free(old_table);
}
/* we have found a valid descriptor, set the value and usage bit */
set_bit(descriptor, map->table->usage);
map->table->mappings[descriptor] = target;
unlock_and_exit:
up_write(&map->lock);
return descriptor;
}
int umpp_descriptor_mapping_lookup(umpp_descriptor_mapping * map, unsigned int descriptor, void** const target)
{
int result = -EINVAL;
UMP_ASSERT(map);
UMP_ASSERT(target);
down_read(&map->lock);
if ( (descriptor > 0) && (descriptor < map->current_nr_mappings) && test_bit(descriptor, map->table->usage) )
{
*target = map->table->mappings[descriptor];
result = 0;
}
/* keep target untouched if the descriptor was not found */
up_read(&map->lock);
return result;
}
void umpp_descriptor_mapping_remove(umpp_descriptor_mapping * map, unsigned int descriptor)
{
UMP_ASSERT(map);
down_write(&map->lock);
if ( (descriptor > 0) && (descriptor < map->current_nr_mappings) && test_bit(descriptor, map->table->usage) )
{
map->table->mappings[descriptor] = NULL;
clear_bit(descriptor, map->table->usage);
}
up_write(&map->lock);
}
static umpp_descriptor_table * descriptor_table_alloc(unsigned int count)
{
umpp_descriptor_table * table;
table = kzalloc(sizeof(umpp_descriptor_table) + ((sizeof(unsigned long) * count)/BITS_PER_LONG) + (sizeof(void*) * count), __GFP_HARDWALL | GFP_KERNEL );
if (NULL != table)
{
table->usage = (unsigned long*)((u8*)table + sizeof(umpp_descriptor_table));
table->mappings = (void**)((u8*)table + sizeof(umpp_descriptor_table) + ((sizeof(unsigned long) * count)/BITS_PER_LONG));
}
return table;
}
static void descriptor_table_free(umpp_descriptor_table * table)
{
UMP_ASSERT(table);
kfree(table);
}
|
