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Diffstat (limited to 'arch/arm/mm/dma-mapping.c')
-rw-r--r--arch/arm/mm/dma-mapping.c48
1 files changed, 36 insertions, 12 deletions
diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index 0a0a1e7c20d2..e4e7f6cba1ab 100644
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c
@@ -18,12 +18,14 @@
#include <linux/device.h>
#include <linux/dma-mapping.h>
#include <linux/highmem.h>
+#include <linux/slab.h>
#include <asm/memory.h>
#include <asm/highmem.h>
#include <asm/cacheflush.h>
#include <asm/tlbflush.h>
#include <asm/sizes.h>
+#include <asm/mach/arch.h>
#include "mm.h"
@@ -117,26 +119,36 @@ static void __dma_free_buffer(struct page *page, size_t size)
}
#ifdef CONFIG_MMU
-/* Sanity check size */
-#if (CONSISTENT_DMA_SIZE % SZ_2M)
-#error "CONSISTENT_DMA_SIZE must be multiple of 2MiB"
-#endif
-#define CONSISTENT_OFFSET(x) (((unsigned long)(x) - CONSISTENT_BASE) >> PAGE_SHIFT)
-#define CONSISTENT_PTE_INDEX(x) (((unsigned long)(x) - CONSISTENT_BASE) >> PGDIR_SHIFT)
-#define NUM_CONSISTENT_PTES (CONSISTENT_DMA_SIZE >> PGDIR_SHIFT)
+#define CONSISTENT_OFFSET(x) (((unsigned long)(x) - consistent_base) >> PAGE_SHIFT)
+#define CONSISTENT_PTE_INDEX(x) (((unsigned long)(x) - consistent_base) >> PMD_SHIFT)
/*
* These are the page tables (2MB each) covering uncached, DMA consistent allocations
*/
-static pte_t *consistent_pte[NUM_CONSISTENT_PTES];
+static pte_t **consistent_pte;
+
+#define DEFAULT_CONSISTENT_DMA_SIZE SZ_2M
+
+unsigned long consistent_base = CONSISTENT_END - DEFAULT_CONSISTENT_DMA_SIZE;
+
+void __init init_consistent_dma_size(unsigned long size)
+{
+ unsigned long base = CONSISTENT_END - ALIGN(size, SZ_2M);
+
+ BUG_ON(consistent_pte); /* Check we're called before DMA region init */
+ BUG_ON(base < VMALLOC_END);
+
+ /* Grow region to accommodate specified size */
+ if (base < consistent_base)
+ consistent_base = base;
+}
#include "vmregion.h"
static struct arm_vmregion_head consistent_head = {
.vm_lock = __SPIN_LOCK_UNLOCKED(&consistent_head.vm_lock),
.vm_list = LIST_HEAD_INIT(consistent_head.vm_list),
- .vm_start = CONSISTENT_BASE,
.vm_end = CONSISTENT_END,
};
@@ -155,7 +167,17 @@ static int __init consistent_init(void)
pmd_t *pmd;
pte_t *pte;
int i = 0;
- u32 base = CONSISTENT_BASE;
+ unsigned long base = consistent_base;
+ unsigned long num_ptes = (CONSISTENT_END - base) >> PGDIR_SHIFT;
+
+ consistent_pte = kmalloc(num_ptes * sizeof(pte_t), GFP_KERNEL);
+ if (!consistent_pte) {
+ pr_err("%s: no memory\n", __func__);
+ return -ENOMEM;
+ }
+
+ pr_debug("DMA memory: 0x%08lx - 0x%08lx:\n", base, CONSISTENT_END);
+ consistent_head.vm_start = base;
do {
pgd = pgd_offset(&init_mm, base);
@@ -183,7 +205,7 @@ static int __init consistent_init(void)
}
consistent_pte[i++] = pte;
- base += (1 << PGDIR_SHIFT);
+ base += PMD_SIZE;
} while (base < CONSISTENT_END);
return ret;
@@ -198,7 +220,7 @@ __dma_alloc_remap(struct page *page, size_t size, gfp_t gfp, pgprot_t prot)
size_t align;
int bit;
- if (!consistent_pte[0]) {
+ if (!consistent_pte) {
printk(KERN_ERR "%s: not initialised\n", __func__);
dump_stack();
return NULL;
@@ -324,6 +346,8 @@ __dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, gfp_t gfp,
if (addr)
*handle = pfn_to_dma(dev, page_to_pfn(page));
+ else
+ __dma_free_buffer(page, size);
return addr;
}