[PATCH 06/11] swiotlb-xen: always use dma-direct helpers to alloc coherent pages

Christoph Hellwig
2019-08-26T12:22:17Z

x86 currently calls alloc_pages, but using dma-direct works as well
there, with the added benefit of using the CMA pool if available.
The biggest advantage is of course to remove a pointless bit of
architecture specific code.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
arch/x86/include/asm/xen/page-coherent.h | 16 ----------------
drivers/xen/swiotlb-xen.c | 7 +++----
include/xen/arm/page-coherent.h | 12 ------------
3 files changed, 3 insertions(+), 32 deletions(-)

diff --git a/arch/x86/include/asm/xen/page-coherent.h b/arch/x86/include/asm/xen/page-coherent.h
index 116777e7f387..8ee33c5edded 100644
--- a/arch/x86/include/asm/xen/page-coherent.h
+++ b/arch/x86/include/asm/xen/page-coherent.h
@@ -5,22 +5,6 @@
#include <asm/page.h>
#include <linux/dma-mapping.h>

-static inline void *xen_alloc_coherent_pages(struct device *hwdev, size_t size,
- dma_addr_t *dma_handle, gfp_t flags,
- unsigned long attrs)
-{
- void *vstart = (void*)__get_free_pages(flags, get_order(size));
- *dma_handle = virt_to_phys(vstart);
- return vstart;
-}
-
-static inline void xen_free_coherent_pages(struct device *hwdev, size_t size,
- void *cpu_addr, dma_addr_t dma_handle,
- unsigned long attrs)
-{
- free_pages((unsigned long) cpu_addr, get_order(size));
-}
-
static inline void xen_dma_map_page(struct device *hwdev, struct page *page,
dma_addr_t dev_addr, unsigned long offset, size_t size,
enum dma_data_direction dir, unsigned long attrs) { }
diff --git a/drivers/xen/swiotlb-xen.c b/drivers/xen/swiotlb-xen.c
index b8808677ae1d..f9dd4cb6e4b3 100644
--- a/drivers/xen/swiotlb-xen.c
+++ b/drivers/xen/swiotlb-xen.c
@@ -299,8 +299,7 @@ xen_swiotlb_alloc_coherent(struct device *hwdev, size_t size,
* address. In fact on ARM virt_to_phys only works for kernel direct
* mapped RAM memory. Also see comment below.
*/
- ret = xen_alloc_coherent_pages(hwdev, size, dma_handle, flags, attrs);
-
+ ret = dma_direct_alloc(hwdev, size, dma_handle, flags, attrs);
if (!ret)
return ret;

@@ -319,7 +318,7 @@ xen_swiotlb_alloc_coherent(struct device *hwdev, size_t size,
else {
if (xen_create_contiguous_region(phys, order,
fls64(dma_mask), dma_handle) != 0) {
- xen_free_coherent_pages(hwdev, size, ret, (dma_addr_t)phys, attrs);
+ dma_direct_free(hwdev, size, ret, (dma_addr_t)phys, attrs);
return NULL;
}
SetPageXenRemapped(virt_to_page(ret));
@@ -351,7 +350,7 @@ xen_swiotlb_free_coherent(struct device *hwdev, size_t size, void *vaddr,
TestClearPageXenRemapped(virt_to_page(vaddr)))
xen_destroy_contiguous_region(phys, order);

- xen_free_coherent_pages(hwdev, size, vaddr, (dma_addr_t)phys, attrs);
+ dma_direct_free(hwdev, size, vaddr, (dma_addr_t)phys, attrs);
}

/*
diff --git a/include/xen/arm/page-coherent.h b/include/xen/arm/page-coherent.h
index a840d6949a87..0e244f4fec1a 100644
--- a/include/xen/arm/page-coherent.h
+++ b/include/xen/arm/page-coherent.h
@@ -16,18 +16,6 @@ void __xen_dma_sync_single_for_cpu(struct device *hwdev,
void __xen_dma_sync_single_for_device(struct device *hwdev,
dma_addr_t handle, size_t size, enum dma_data_direction dir);

-static inline void *xen_alloc_coherent_pages(struct device *hwdev, size_t size,
- dma_addr_t *dma_handle, gfp_t flags, unsigned long attrs)
-{
- return dma_direct_alloc(hwdev, size, dma_handle, flags, attrs);
-}
-
-static inline void xen_free_coherent_pages(struct device *hwdev, size_t size,
- void *cpu_addr, dma_addr_t dma_handle, unsigned long attrs)
-{
- dma_direct_free(hwdev, size, cpu_addr, dma_handle, attrs);
-}
-
static inline void xen_dma_sync_single_for_cpu(struct device *hwdev,
dma_addr_t handle, size_t size, enum dma_data_direction dir)
{
--
2.20.1