summaryrefslogtreecommitdiffstats
path: root/sound/pci/ctxfi/ctvmem.c
blob: 6109490b83e83294373f36956a5a8a01dd923e20 (plain)
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
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
/**
 * Copyright (C) 2008, Creative Technology Ltd. All Rights Reserved.
 *
 * This source file is released under GPL v2 license (no other versions).
 * See the COPYING file included in the main directory of this source
 * distribution for the license terms and conditions.
 *
 * @File    ctvmem.c
 *
 * @Brief
 * This file contains the implementation of virtual memory management object
 * for card device.
 *
 * @Author Liu Chun
 * @Date Apr 1 2008
 */

#include "ctvmem.h"
#include <linux/slab.h>
#include <linux/mm.h>
#include <linux/io.h>
#include <sound/pcm.h>

#define CT_PTES_PER_PAGE (CT_PAGE_SIZE / sizeof(void *))
#define CT_ADDRS_PER_PAGE (CT_PTES_PER_PAGE * CT_PAGE_SIZE)

/* *
 * Find or create vm block based on requested @size.
 * @size must be page aligned.
 * */
static struct ct_vm_block *
get_vm_block(struct ct_vm *vm, unsigned int size)
{
	struct ct_vm_block *block = NULL, *entry;
	struct list_head *pos;

	size = CT_PAGE_ALIGN(size);
	if (size > vm->size) {
		printk(KERN_ERR "ctxfi: Fail! No sufficient device virtual "
				  "memory space available!\n");
		return NULL;
	}

	mutex_lock(&vm->lock);
	list_for_each(pos, &vm->unused) {
		entry = list_entry(pos, struct ct_vm_block, list);
		if (entry->size >= size)
			break; /* found a block that is big enough */
	}
	if (pos == &vm->unused)
		goto out;

	if (entry->size == size) {
		/* Move the vm node from unused list to used list directly */
		list_move(&entry->list, &vm->used);
		vm->size -= size;
		block = entry;
		goto out;
	}

	block = kzalloc(sizeof(*block), GFP_KERNEL);
	if (!block)
		goto out;

	block->addr = entry->addr;
	block->size = size;
	list_add(&block->list, &vm->used);
	entry->addr += size;
	entry->size -= size;
	vm->size -= size;

 out:
	mutex_unlock(&vm->lock);
	return block;
}

static void put_vm_block(struct ct_vm *vm, struct ct_vm_block *block)
{
	struct ct_vm_block *entry, *pre_ent;
	struct list_head *pos, *pre;

	block->size = CT_PAGE_ALIGN(block->size);

	mutex_lock(&vm->lock);
	list_del(&block->list);
	vm->size += block->size;

	list_for_each(pos, &vm->unused) {
		entry = list_entry(pos, struct ct_vm_block, list);
		if (entry->addr >= (block->addr + block->size))
			break; /* found a position */
	}
	if (pos == &vm->unused) {
		list_add_tail(&block->list, &vm->unused);
		entry = block;
	} else {
		if ((block->addr + block->size) == entry->addr) {
			entry->addr = block->addr;
			entry->size += block->size;
			kfree(block);
		} else {
			__list_add(&block->list, pos->prev, pos);
			entry = block;
		}
	}

	pos = &entry->list;
	pre = pos->prev;
	while (pre != &vm->unused) {
		entry = list_entry(pos, struct ct_vm_block, list);
		pre_ent = list_entry(pre, struct ct_vm_block, list);
		if ((pre_ent->addr + pre_ent->size) > entry->addr)
			break;

		pre_ent->size += entry->size;
		list_del(pos);
		kfree(entry);
		pos = pre;
		pre = pos->prev;
	}
	mutex_unlock(&vm->lock);
}

/* Map host addr (kmalloced/vmalloced) to device logical addr. */
static struct ct_vm_block *
ct_vm_map(struct ct_vm *vm, struct snd_pcm_substream *substream, int size)
{
	struct ct_vm_block *block;
	unsigned int pte_start;
	unsigned i, pages;
	unsigned long *ptp;

	block = get_vm_block(vm, size);
	if (block == NULL) {
		printk(KERN_ERR "ctxfi: No virtual memory block that is big "
				  "enough to allocate!\n");
		return NULL;
	}

	ptp = (unsigned long *)vm->ptp[0].area;
	pte_start = (block->addr >> CT_PAGE_SHIFT);
	pages = block->size >> CT_PAGE_SHIFT;
	for (i = 0; i < pages; i++) {
		unsigned long addr;
		addr = snd_pcm_sgbuf_get_addr(substream, i << CT_PAGE_SHIFT);
		ptp[pte_start + i] = addr;
	}

	block->size = size;
	return block;
}

static void ct_vm_unmap(struct ct_vm *vm, struct ct_vm_block *block)
{
	/* do unmapping */
	put_vm_block(vm, block);
}

/* *
 * return the host physical addr of the @index-th device
 * page table page on success, or ~0UL on failure.
 * The first returned ~0UL indicates the termination.
 * */
static dma_addr_t
ct_get_ptp_phys(struct ct_vm *vm, int index)
{
	dma_addr_t addr;

	addr = (index >= CT_PTP_NUM) ? ~0UL : vm->ptp[index].addr;

	return addr;
}

int ct_vm_create(struct ct_vm **rvm, struct pci_dev *pci)
{
	struct ct_vm *vm;
	struct ct_vm_block *block;
	int i, err = 0;

	*rvm = NULL;

	vm = kzalloc(sizeof(*vm), GFP_KERNEL);
	if (!vm)
		return -ENOMEM;

	mutex_init(&vm->lock);

	/* Allocate page table pages */
	for (i = 0; i < CT_PTP_NUM; i++) {
		err = snd_dma_alloc_pages(SNDRV_DMA_TYPE_DEV,
					  snd_dma_pci_data(pci),
					  PAGE_SIZE, &vm->ptp[i]);
		if (err < 0)
			break;
	}
	if (err < 0) {
		/* no page table pages are allocated */
		ct_vm_destroy(vm);
		return -ENOMEM;
	}
	vm->size = CT_ADDRS_PER_PAGE * i;
	vm->map = ct_vm_map;
	vm->unmap = ct_vm_unmap;
	vm->get_ptp_phys = ct_get_ptp_phys;
	INIT_LIST_HEAD(&vm->unused);
	INIT_LIST_HEAD(&vm->used);
	block = kzalloc(sizeof(*block), GFP_KERNEL);
	if (NULL != block) {
		block->addr = 0;
		block->size = vm->size;
		list_add(&block->list, &vm->unused);
	}

	*rvm = vm;
	return 0;
}

/* The caller must ensure no mapping pages are being used
 * by hardware before calling this function */
void ct_vm_destroy(struct ct_vm *vm)
{
	int i;
	struct list_head *pos;
	struct ct_vm_block *entry;

	/* free used and unused list nodes */
	while (!list_empty(&vm->used)) {
		pos = vm->used.next;
		list_del(pos);
		entry = list_entry(pos, struct ct_vm_block, list);
		kfree(entry);
	}
	while (!list_empty(&vm->unused)) {
		pos = vm->unused.next;
		list_del(pos);
		entry = list_entry(pos, struct ct_vm_block, list);
		kfree(entry);
	}

	/* free allocated page table pages */
	for (i = 0; i < CT_PTP_NUM; i++)
		snd_dma_free_pages(&vm->ptp[i]);

	vm->size = 0;

	kfree(vm);
}
OpenPOWER on IntegriCloud