X86: integrate CMA with DMA-mapping subsystem
This patch adds support for CMA to dma-mapping subsystem for x86
architecture that uses common pci-dma/pci-nommu implementation. This
allows to test CMA on KVM/QEMU and a lot of common x86 boxes.
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
CC: Michal Nazarewicz <mina86@mina86.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c
index 3003250..62c9457 100644
--- a/arch/x86/kernel/pci-dma.c
+++ b/arch/x86/kernel/pci-dma.c
@@ -100,14 +100,18 @@
struct dma_attrs *attrs)
{
unsigned long dma_mask;
- struct page *page;
+ struct page *page = NULL;
+ unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
dma_addr_t addr;
dma_mask = dma_alloc_coherent_mask(dev, flag);
flag |= __GFP_ZERO;
again:
- page = alloc_pages_node(dev_to_node(dev), flag, get_order(size));
+ if (!(flag & GFP_ATOMIC))
+ page = dma_alloc_from_contiguous(dev, count, get_order(size));
+ if (!page)
+ page = alloc_pages_node(dev_to_node(dev), flag, get_order(size));
if (!page)
return NULL;
@@ -127,6 +131,16 @@
return page_address(page);
}
+void dma_generic_free_coherent(struct device *dev, size_t size, void *vaddr,
+ dma_addr_t dma_addr, struct dma_attrs *attrs)
+{
+ unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
+ struct page *page = virt_to_page(vaddr);
+
+ if (!dma_release_from_contiguous(dev, page, count))
+ free_pages((unsigned long)vaddr, get_order(size));
+}
+
/*
* See <Documentation/x86/x86_64/boot-options.txt> for the iommu kernel
* parameter documentation.
diff --git a/arch/x86/kernel/pci-nommu.c b/arch/x86/kernel/pci-nommu.c
index f960506..871be4a 100644
--- a/arch/x86/kernel/pci-nommu.c
+++ b/arch/x86/kernel/pci-nommu.c
@@ -74,12 +74,6 @@
return nents;
}
-static void nommu_free_coherent(struct device *dev, size_t size, void *vaddr,
- dma_addr_t dma_addr, struct dma_attrs *attrs)
-{
- free_pages((unsigned long)vaddr, get_order(size));
-}
-
static void nommu_sync_single_for_device(struct device *dev,
dma_addr_t addr, size_t size,
enum dma_data_direction dir)
@@ -97,7 +91,7 @@
struct dma_map_ops nommu_dma_ops = {
.alloc = dma_generic_alloc_coherent,
- .free = nommu_free_coherent,
+ .free = dma_generic_free_coherent,
.map_sg = nommu_map_sg,
.map_page = nommu_map_page,
.sync_single_for_device = nommu_sync_single_for_device,
diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
index 1a29015..d6c956e 100644
--- a/arch/x86/kernel/setup.c
+++ b/arch/x86/kernel/setup.c
@@ -50,6 +50,7 @@
#include <asm/pci-direct.h>
#include <linux/init_ohci1394_dma.h>
#include <linux/kvm_para.h>
+#include <linux/dma-contiguous.h>
#include <linux/errno.h>
#include <linux/kernel.h>
@@ -934,6 +935,7 @@
}
#endif
memblock.current_limit = get_max_mapped();
+ dma_contiguous_reserve(0);
/*
* NOTE: On x86-32, only from this point on, fixmaps are ready for use.