8dfcc9ba27
Have an explicit mm call to split higher order pages into individual pages. Should help to avoid bugs and be more explicit about the code's intention. Signed-off-by: Nick Piggin <npiggin@suse.de> Cc: Russell King <rmk@arm.linux.org.uk> Cc: David Howells <dhowells@redhat.com> Cc: Ralf Baechle <ralf@linux-mips.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mundt <lethal@linux-sh.org> Cc: "David S. Miller" <davem@davemloft.net> Cc: Chris Zankel <chris@zankel.net> Signed-off-by: Yoichi Yuasa <yoichi_yuasa@tripeaks.co.jp> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
85 lines
1.7 KiB
C
85 lines
1.7 KiB
C
/*
|
|
* arch/sh/mm/consistent.c
|
|
*
|
|
* Copyright (C) 2004 Paul Mundt
|
|
*
|
|
* This file is subject to the terms and conditions of the GNU General Public
|
|
* License. See the file "COPYING" in the main directory of this archive
|
|
* for more details.
|
|
*/
|
|
#include <linux/mm.h>
|
|
#include <linux/dma-mapping.h>
|
|
#include <asm/io.h>
|
|
|
|
void *consistent_alloc(gfp_t gfp, size_t size, dma_addr_t *handle)
|
|
{
|
|
struct page *page, *end, *free;
|
|
void *ret;
|
|
int order;
|
|
|
|
size = PAGE_ALIGN(size);
|
|
order = get_order(size);
|
|
|
|
page = alloc_pages(gfp, order);
|
|
if (!page)
|
|
return NULL;
|
|
split_page(page, order);
|
|
|
|
ret = page_address(page);
|
|
*handle = virt_to_phys(ret);
|
|
|
|
/*
|
|
* We must flush the cache before we pass it on to the device
|
|
*/
|
|
dma_cache_wback_inv(ret, size);
|
|
|
|
page = virt_to_page(ret);
|
|
free = page + (size >> PAGE_SHIFT);
|
|
end = page + (1 << order);
|
|
|
|
while (++page < end) {
|
|
/* Free any unused pages */
|
|
if (page >= free) {
|
|
__free_page(page);
|
|
}
|
|
}
|
|
|
|
return P2SEGADDR(ret);
|
|
}
|
|
|
|
void consistent_free(void *vaddr, size_t size)
|
|
{
|
|
unsigned long addr = P1SEGADDR((unsigned long)vaddr);
|
|
struct page *page=virt_to_page(addr);
|
|
int num_pages=(size+PAGE_SIZE-1) >> PAGE_SHIFT;
|
|
int i;
|
|
|
|
for(i=0;i<num_pages;i++) {
|
|
__free_page((page+i));
|
|
}
|
|
}
|
|
|
|
void consistent_sync(void *vaddr, size_t size, int direction)
|
|
{
|
|
void * p1addr = (void*) P1SEGADDR((unsigned long)vaddr);
|
|
|
|
switch (direction) {
|
|
case DMA_FROM_DEVICE: /* invalidate only */
|
|
dma_cache_inv(p1addr, size);
|
|
break;
|
|
case DMA_TO_DEVICE: /* writeback only */
|
|
dma_cache_wback(p1addr, size);
|
|
break;
|
|
case DMA_BIDIRECTIONAL: /* writeback and invalidate */
|
|
dma_cache_wback_inv(p1addr, size);
|
|
break;
|
|
default:
|
|
BUG();
|
|
}
|
|
}
|
|
|
|
EXPORT_SYMBOL(consistent_alloc);
|
|
EXPORT_SYMBOL(consistent_free);
|
|
EXPORT_SYMBOL(consistent_sync);
|
|
|