Blackfin: convert DMA code to a proper bitmap
authorMichael Hennerich <michael.hennerich@analog.com>
Wed, 23 Sep 2009 11:32:52 +0000 (11:32 +0000)
committerMike Frysinger <vapier@gentoo.org>
Tue, 15 Dec 2009 05:13:51 +0000 (00:13 -0500)
Rather than using our own data structures that basically boil down to a
bitmap, use the standard bitmap functions.

Reported-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
arch/blackfin/kernel/dma-mapping.c

index e74e74d7733ff254ecb5cba001eeb28765be2c94..be81572b89c2cf2a4f4ac84ba92ec1229bedf2cd 100644 (file)
@@ -19,7 +19,7 @@
 #include <asm/bfin-global.h>
 
 static spinlock_t dma_page_lock;
-static unsigned int *dma_page;
+static unsigned long *dma_page;
 static unsigned int dma_pages;
 static unsigned long dma_base;
 static unsigned long dma_size;
@@ -30,7 +30,7 @@ void dma_alloc_init(unsigned long start, unsigned long end)
        spin_lock_init(&dma_page_lock);
        dma_initialized = 0;
 
-       dma_page = (unsigned int *)__get_free_page(GFP_KERNEL);
+       dma_page = (unsigned long *)__get_free_page(GFP_KERNEL);
        memset(dma_page, 0, PAGE_SIZE);
        dma_base = PAGE_ALIGN(start);
        dma_size = PAGE_ALIGN(end) - PAGE_ALIGN(start);
@@ -58,10 +58,11 @@ static unsigned long __alloc_dma_pages(unsigned int pages)
        spin_lock_irqsave(&dma_page_lock, flags);
 
        for (i = 0; i < dma_pages;) {
-               if (dma_page[i++] == 0) {
+               if (test_bit(i++, dma_page) == 0) {
                        if (++count == pages) {
                                while (count--)
-                                       dma_page[--i] = 1;
+                                       __set_bit(--i, dma_page);
+
                                ret = dma_base + (i << PAGE_SHIFT);
                                break;
                        }
@@ -84,9 +85,9 @@ static void __free_dma_pages(unsigned long addr, unsigned int pages)
        }
 
        spin_lock_irqsave(&dma_page_lock, flags);
-       for (i = page; i < page + pages; i++) {
-               dma_page[i] = 0;
-       }
+       for (i = page; i < page + pages; i++)
+               __clear_bit(i, dma_page);
+
        spin_unlock_irqrestore(&dma_page_lock, flags);
 }