2 * Copyright (C) 2008, Creative Technology Ltd. All Rights Reserved.
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.
11 * This file contains the implementation of virtual memory management object
19 #include <linux/slab.h>
22 #include <sound/pcm.h>
24 #define CT_PTES_PER_PAGE (CT_PAGE_SIZE / sizeof(void *))
25 #define CT_ADDRS_PER_PAGE (CT_PTES_PER_PAGE * CT_PAGE_SIZE)
28 * Find or create vm block based on requested @size.
29 * @size must be page aligned.
31 static struct ct_vm_block *
32 get_vm_block(struct ct_vm *vm, unsigned int size)
34 struct ct_vm_block *block = NULL, *entry;
35 struct list_head *pos;
37 size = CT_PAGE_ALIGN(size);
38 if (size > vm->size) {
39 printk(KERN_ERR "ctxfi: Fail! No sufficient device virtual "
40 "memory space available!\n");
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 */
50 if (pos == &vm->unused)
53 if (entry->size == size) {
54 /* Move the vm node from unused list to used list directly */
55 list_move(&entry->list, &vm->used);
61 block = kzalloc(sizeof(*block), GFP_KERNEL);
65 block->addr = entry->addr;
67 list_add(&block->list, &vm->used);
73 mutex_unlock(&vm->lock);
77 static void put_vm_block(struct ct_vm *vm, struct ct_vm_block *block)
79 struct ct_vm_block *entry, *pre_ent;
80 struct list_head *pos, *pre;
82 block->size = CT_PAGE_ALIGN(block->size);
84 mutex_lock(&vm->lock);
85 list_del(&block->list);
86 vm->size += block->size;
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 */
93 if (pos == &vm->unused) {
94 list_add_tail(&block->list, &vm->unused);
97 if ((block->addr + block->size) == entry->addr) {
98 entry->addr = block->addr;
99 entry->size += block->size;
102 __list_add(&block->list, pos->prev, pos);
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)
115 pre_ent->size += entry->size;
121 mutex_unlock(&vm->lock);
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)
128 struct ct_vm_block *block;
129 unsigned int pte_start;
133 block = get_vm_block(vm, size);
135 printk(KERN_ERR "ctxfi: No virtual memory block that is big "
136 "enough to allocate!\n");
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++) {
145 addr = snd_pcm_sgbuf_get_addr(substream, i << CT_PAGE_SHIFT);
146 ptp[pte_start + i] = addr;
153 static void ct_vm_unmap(struct ct_vm *vm, struct ct_vm_block *block)
156 put_vm_block(vm, block);
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.
165 ct_get_ptp_phys(struct ct_vm *vm, int index)
169 addr = (index >= CT_PTP_NUM) ? ~0UL : vm->ptp[index].addr;
174 int ct_vm_create(struct ct_vm **rvm, struct pci_dev *pci)
177 struct ct_vm_block *block;
182 vm = kzalloc(sizeof(*vm), GFP_KERNEL);
186 mutex_init(&vm->lock);
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]);
197 /* no page table pages are allocated */
201 vm->size = CT_ADDRS_PER_PAGE * i;
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);
210 block->size = vm->size;
211 list_add(&block->list, &vm->unused);
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)
223 struct list_head *pos;
224 struct ct_vm_block *entry;
226 /* free used and unused list nodes */
227 while (!list_empty(&vm->used)) {
230 entry = list_entry(pos, struct ct_vm_block, list);
233 while (!list_empty(&vm->unused)) {
234 pos = vm->unused.next;
236 entry = list_entry(pos, struct ct_vm_block, list);
240 /* free allocated page table pages */
241 for (i = 0; i < CT_PTP_NUM; i++)
242 snd_dma_free_pages(&vm->ptp[i]);