linux/arch/cris/arch-v32/mm/intmem.c

140 lines
3.4 KiB
C

/*
* Simple allocator for internal RAM in ETRAX FS
*
* Copyright (c) 2004 Axis Communications AB.
*/
#include <linux/list.h>
#include <linux/slab.h>
#include <asm/io.h>
#include <asm/arch/memmap.h>
#define STATUS_FREE 0
#define STATUS_ALLOCATED 1
struct intmem_allocation {
struct list_head entry;
unsigned int size;
unsigned offset;
char status;
};
static struct list_head intmem_allocations;
static void* intmem_virtual;
static void crisv32_intmem_init(void)
{
static int initiated = 0;
if (!initiated) {
struct intmem_allocation* alloc =
(struct intmem_allocation*)kmalloc(sizeof *alloc, GFP_KERNEL);
INIT_LIST_HEAD(&intmem_allocations);
intmem_virtual = ioremap(MEM_INTMEM_START, MEM_INTMEM_SIZE);
initiated = 1;
alloc->size = MEM_INTMEM_SIZE;
alloc->offset = 0;
alloc->status = STATUS_FREE;
list_add_tail(&alloc->entry, &intmem_allocations);
}
}
void* crisv32_intmem_alloc(unsigned size, unsigned align)
{
struct intmem_allocation* allocation;
struct intmem_allocation* tmp;
void* ret = NULL;
preempt_disable();
crisv32_intmem_init();
list_for_each_entry_safe(allocation, tmp, &intmem_allocations, entry) {
int alignment = allocation->offset % align;
alignment = alignment ? align - alignment : alignment;
if (allocation->status == STATUS_FREE &&
allocation->size >= size + alignment) {
if (allocation->size > size + alignment) {
struct intmem_allocation* alloc =
(struct intmem_allocation*)
kmalloc(sizeof *alloc, GFP_ATOMIC);
alloc->status = STATUS_FREE;
alloc->size = allocation->size - size - alignment;
alloc->offset = allocation->offset + size;
list_add(&alloc->entry, &allocation->entry);
if (alignment) {
struct intmem_allocation* tmp;
tmp = (struct intmem_allocation*)
kmalloc(sizeof *tmp, GFP_ATOMIC);
tmp->offset = allocation->offset;
tmp->size = alignment;
tmp->status = STATUS_FREE;
allocation->offset += alignment;
list_add_tail(&tmp->entry, &allocation->entry);
}
}
allocation->status = STATUS_ALLOCATED;
allocation->size = size;
ret = (void*)((int)intmem_virtual + allocation->offset);
}
}
preempt_enable();
return ret;
}
void crisv32_intmem_free(void* addr)
{
struct intmem_allocation* allocation;
struct intmem_allocation* tmp;
if (addr == NULL)
return;
preempt_disable();
crisv32_intmem_init();
list_for_each_entry_safe(allocation, tmp, &intmem_allocations, entry) {
if (allocation->offset == (int)(addr - intmem_virtual)) {
struct intmem_allocation* prev =
list_entry(allocation->entry.prev,
struct intmem_allocation, entry);
struct intmem_allocation* next =
list_entry(allocation->entry.next,
struct intmem_allocation, entry);
allocation->status = STATUS_FREE;
/* Join with prev and/or next if also free */
if (prev->status == STATUS_FREE) {
prev->size += allocation->size;
list_del(&allocation->entry);
kfree(allocation);
allocation = prev;
}
if (next->status == STATUS_FREE) {
allocation->size += next->size;
list_del(&next->entry);
kfree(next);
}
preempt_enable();
return;
}
}
preempt_enable();
}
void* crisv32_intmem_phys_to_virt(unsigned long addr)
{
return (void*)(addr - MEM_INTMEM_START+
(unsigned long)intmem_virtual);
}
unsigned long crisv32_intmem_virt_to_phys(void* addr)
{
return (unsigned long)((unsigned long )addr -
(unsigned long)intmem_virtual + MEM_INTMEM_START);
}