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Viewing changes to sound/pci/ctxfi/ctvmem.c

  • Committer: Package Import Robot
  • Author(s): Alessio Igor Bogani
  • Date: 2011-10-26 11:13:05 UTC
  • Revision ID: package-import@ubuntu.com-20111026111305-tz023xykf0i6eosh
Tags: upstream-3.2.0
Import upstream version 3.2.0

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sound/pci/ctxfi/ctvmem.c
 
1
/**
 
2
 * Copyright (C) 2008, Creative Technology Ltd. All Rights Reserved.
 
3
 *
 
4
 * This source file is released under GPL v2 license (no other versions).
 
5
 * See the COPYING file included in the main directory of this source
 
6
 * distribution for the license terms and conditions.
 
7
 *
 
8
 * @File    ctvmem.c
 
9
 *
 
10
 * @Brief
 
11
 * This file contains the implementation of virtual memory management object
 
12
 * for card device.
 
13
 *
 
14
 * @Author Liu Chun
 
15
 * @Date Apr 1 2008
 
16
 */
 
17
 
 
18
#include "ctvmem.h"
 
19
#include <linux/slab.h>
 
20
#include <linux/mm.h>
 
21
#include <linux/io.h>
 
22
#include <sound/pcm.h>
 
23
 
 
24
#define CT_PTES_PER_PAGE (CT_PAGE_SIZE / sizeof(void *))
 
25
#define CT_ADDRS_PER_PAGE (CT_PTES_PER_PAGE * CT_PAGE_SIZE)
 
26
 
 
27
/* *
 
28
 * Find or create vm block based on requested @size.
 
29
 * @size must be page aligned.
 
30
 * */
 
31
static struct ct_vm_block *
 
32
get_vm_block(struct ct_vm *vm, unsigned int size)
 
33
{
 
34
        struct ct_vm_block *block = NULL, *entry;
 
35
        struct list_head *pos;
 
36
 
 
37
        size = CT_PAGE_ALIGN(size);
 
38
        if (size > vm->size) {
 
39
                printk(KERN_ERR "ctxfi: Fail! No sufficient device virtural "
 
40
                                  "memory space available!\n");
 
41
                return NULL;
 
42
        }
 
43
 
 
44
        mutex_lock(&vm->lock);
 
45
        list_for_each(pos, &vm->unused) {
 
46
                entry = list_entry(pos, struct ct_vm_block, list);
 
47
                if (entry->size >= size)
 
48
                        break; /* found a block that is big enough */
 
49
        }
 
50
        if (pos == &vm->unused)
 
51
                goto out;
 
52
 
 
53
        if (entry->size == size) {
 
54
                /* Move the vm node from unused list to used list directly */
 
55
                list_move(&entry->list, &vm->used);
 
56
                vm->size -= size;
 
57
                block = entry;
 
58
                goto out;
 
59
        }
 
60
 
 
61
        block = kzalloc(sizeof(*block), GFP_KERNEL);
 
62
        if (!block)
 
63
                goto out;
 
64
 
 
65
        block->addr = entry->addr;
 
66
        block->size = size;
 
67
        list_add(&block->list, &vm->used);
 
68
        entry->addr += size;
 
69
        entry->size -= size;
 
70
        vm->size -= size;
 
71
 
 
72
 out:
 
73
        mutex_unlock(&vm->lock);
 
74
        return block;
 
75
}
 
76
 
 
77
static void put_vm_block(struct ct_vm *vm, struct ct_vm_block *block)
 
78
{
 
79
        struct ct_vm_block *entry, *pre_ent;
 
80
        struct list_head *pos, *pre;
 
81
 
 
82
        block->size = CT_PAGE_ALIGN(block->size);
 
83
 
 
84
        mutex_lock(&vm->lock);
 
85
        list_del(&block->list);
 
86
        vm->size += block->size;
 
87
 
 
88
        list_for_each(pos, &vm->unused) {
 
89
                entry = list_entry(pos, struct ct_vm_block, list);
 
90
                if (entry->addr >= (block->addr + block->size))
 
91
                        break; /* found a position */
 
92
        }
 
93
        if (pos == &vm->unused) {
 
94
                list_add_tail(&block->list, &vm->unused);
 
95
                entry = block;
 
96
        } else {
 
97
                if ((block->addr + block->size) == entry->addr) {
 
98
                        entry->addr = block->addr;
 
99
                        entry->size += block->size;
 
100
                        kfree(block);
 
101
                } else {
 
102
                        __list_add(&block->list, pos->prev, pos);
 
103
                        entry = block;
 
104
                }
 
105
        }
 
106
 
 
107
        pos = &entry->list;
 
108
        pre = pos->prev;
 
109
        while (pre != &vm->unused) {
 
110
                entry = list_entry(pos, struct ct_vm_block, list);
 
111
                pre_ent = list_entry(pre, struct ct_vm_block, list);
 
112
                if ((pre_ent->addr + pre_ent->size) > entry->addr)
 
113
                        break;
 
114
 
 
115
                pre_ent->size += entry->size;
 
116
                list_del(pos);
 
117
                kfree(entry);
 
118
                pos = pre;
 
119
                pre = pos->prev;
 
120
        }
 
121
        mutex_unlock(&vm->lock);
 
122
}
 
123
 
 
124
/* Map host addr (kmalloced/vmalloced) to device logical addr. */
 
125
static struct ct_vm_block *
 
126
ct_vm_map(struct ct_vm *vm, struct snd_pcm_substream *substream, int size)
 
127
{
 
128
        struct ct_vm_block *block;
 
129
        unsigned int pte_start;
 
130
        unsigned i, pages;
 
131
        unsigned long *ptp;
 
132
 
 
133
        block = get_vm_block(vm, size);
 
134
        if (block == NULL) {
 
135
                printk(KERN_ERR "ctxfi: No virtual memory block that is big "
 
136
                                  "enough to allocate!\n");
 
137
                return NULL;
 
138
        }
 
139
 
 
140
        ptp = (unsigned long *)vm->ptp[0].area;
 
141
        pte_start = (block->addr >> CT_PAGE_SHIFT);
 
142
        pages = block->size >> CT_PAGE_SHIFT;
 
143
        for (i = 0; i < pages; i++) {
 
144
                unsigned long addr;
 
145
                addr = snd_pcm_sgbuf_get_addr(substream, i << CT_PAGE_SHIFT);
 
146
                ptp[pte_start + i] = addr;
 
147
        }
 
148
 
 
149
        block->size = size;
 
150
        return block;
 
151
}
 
152
 
 
153
static void ct_vm_unmap(struct ct_vm *vm, struct ct_vm_block *block)
 
154
{
 
155
        /* do unmapping */
 
156
        put_vm_block(vm, block);
 
157
}
 
158
 
 
159
/* *
 
160
 * return the host physical addr of the @index-th device
 
161
 * page table page on success, or ~0UL on failure.
 
162
 * The first returned ~0UL indicates the termination.
 
163
 * */
 
164
static dma_addr_t
 
165
ct_get_ptp_phys(struct ct_vm *vm, int index)
 
166
{
 
167
        dma_addr_t addr;
 
168
 
 
169
        addr = (index >= CT_PTP_NUM) ? ~0UL : vm->ptp[index].addr;
 
170
 
 
171
        return addr;
 
172
}
 
173
 
 
174
int ct_vm_create(struct ct_vm **rvm, struct pci_dev *pci)
 
175
{
 
176
        struct ct_vm *vm;
 
177
        struct ct_vm_block *block;
 
178
        int i, err = 0;
 
179
 
 
180
        *rvm = NULL;
 
181
 
 
182
        vm = kzalloc(sizeof(*vm), GFP_KERNEL);
 
183
        if (!vm)
 
184
                return -ENOMEM;
 
185
 
 
186
        mutex_init(&vm->lock);
 
187
 
 
188
        /* Allocate page table pages */
 
189
        for (i = 0; i < CT_PTP_NUM; i++) {
 
190
                err = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV,
 
191
                                          snd_dma_pci_data(pci),
 
192
                                          PAGE_SIZE, &vm->ptp[i]);
 
193
                if (err < 0)
 
194
                        break;
 
195
        }
 
196
        if (err < 0) {
 
197
                /* no page table pages are allocated */
 
198
                ct_vm_destroy(vm);
 
199
                return -ENOMEM;
 
200
        }
 
201
        vm->size = CT_ADDRS_PER_PAGE * i;
 
202
        vm->map = ct_vm_map;
 
203
        vm->unmap = ct_vm_unmap;
 
204
        vm->get_ptp_phys = ct_get_ptp_phys;
 
205
        INIT_LIST_HEAD(&vm->unused);
 
206
        INIT_LIST_HEAD(&vm->used);
 
207
        block = kzalloc(sizeof(*block), GFP_KERNEL);
 
208
        if (NULL != block) {
 
209
                block->addr = 0;
 
210
                block->size = vm->size;
 
211
                list_add(&block->list, &vm->unused);
 
212
        }
 
213
 
 
214
        *rvm = vm;
 
215
        return 0;
 
216
}
 
217
 
 
218
/* The caller must ensure no mapping pages are being used
 
219
 * by hardware before calling this function */
 
220
void ct_vm_destroy(struct ct_vm *vm)
 
221
{
 
222
        int i;
 
223
        struct list_head *pos;
 
224
        struct ct_vm_block *entry;
 
225
 
 
226
        /* free used and unused list nodes */
 
227
        while (!list_empty(&vm->used)) {
 
228
                pos = vm->used.next;
 
229
                list_del(pos);
 
230
                entry = list_entry(pos, struct ct_vm_block, list);
 
231
                kfree(entry);
 
232
        }
 
233
        while (!list_empty(&vm->unused)) {
 
234
                pos = vm->unused.next;
 
235
                list_del(pos);
 
236
                entry = list_entry(pos, struct ct_vm_block, list);
 
237
                kfree(entry);
 
238
        }
 
239
 
 
240
        /* free allocated page table pages */
 
241
        for (i = 0; i < CT_PTP_NUM; i++)
 
242
                snd_dma_free_pages(&vm->ptp[i]);
 
243
 
 
244
        vm->size = 0;
 
245
 
 
246
        kfree(vm);
 
247
}