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Diffstat (limited to 'sound/pci/ctxfi/ctvmem.c')
-rw-r--r--sound/pci/ctxfi/ctvmem.c250
1 files changed, 250 insertions, 0 deletions
diff --git a/sound/pci/ctxfi/ctvmem.c b/sound/pci/ctxfi/ctvmem.c
new file mode 100644
index 0000000..67665a7
--- /dev/null
+++ b/sound/pci/ctxfi/ctvmem.c
@@ -0,0 +1,250 @@
+/**
+ * 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 virtural "
+ "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_del(&entry->list);
+ list_add(&entry->list, &vm->used);
+ vm->size -= size;
+ block = entry;
+ goto out;
+ }
+
+ block = kzalloc(sizeof(*block), GFP_KERNEL);
+ if (NULL == 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 = vm->ptp[0];
+ 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 (kmalloced) addr of the @index-th device
+ * page talbe page on success, or NULL on failure.
+ * The first returned NULL indicates the termination.
+ * */
+static void *
+ct_get_ptp_virt(struct ct_vm *vm, int index)
+{
+ void *addr;
+
+ addr = (index >= CT_PTP_NUM) ? NULL : vm->ptp[index];
+
+ return addr;
+}
+
+int ct_vm_create(struct ct_vm **rvm)
+{
+ struct ct_vm *vm;
+ struct ct_vm_block *block;
+ int i;
+
+ *rvm = NULL;
+
+ vm = kzalloc(sizeof(*vm), GFP_KERNEL);
+ if (NULL == vm)
+ return -ENOMEM;
+
+ mutex_init(&vm->lock);
+
+ /* Allocate page table pages */
+ for (i = 0; i < CT_PTP_NUM; i++) {
+ vm->ptp[i] = kmalloc(PAGE_SIZE, GFP_KERNEL);
+ if (NULL == vm->ptp[i])
+ break;
+ }
+ if (!i) {
+ /* no page table pages are allocated */
+ kfree(vm);
+ return -ENOMEM;
+ }
+ vm->size = CT_ADDRS_PER_PAGE * i;
+ /* Initialise remaining ptps */
+ for (; i < CT_PTP_NUM; i++)
+ vm->ptp[i] = NULL;
+
+ vm->map = ct_vm_map;
+ vm->unmap = ct_vm_unmap;
+ vm->get_ptp_virt = ct_get_ptp_virt;
+ 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++)
+ kfree(vm->ptp[i]);
+
+ vm->size = 0;
+
+ kfree(vm);
+}