[PATCH 5/7] dma-direct: handle DMA_ATTR_NON_CONSISTENT in common code

From: Christoph Hellwig
Date: Fri Jun 14 2019 - 10:50:00 EST


Only call into arch_dma_alloc if we require an uncached mapping,
and remove the parisc code manually doing normal cached
DMA_ATTR_NON_CONSISTENT allocations.

Signed-off-by: Christoph Hellwig <hch@xxxxxx>
---
arch/parisc/kernel/pci-dma.c | 48 ++++++++++--------------------------
kernel/dma/direct.c | 4 +--
2 files changed, 15 insertions(+), 37 deletions(-)

diff --git a/arch/parisc/kernel/pci-dma.c b/arch/parisc/kernel/pci-dma.c
index 239162355b58..ca35d9a76e50 100644
--- a/arch/parisc/kernel/pci-dma.c
+++ b/arch/parisc/kernel/pci-dma.c
@@ -394,17 +394,20 @@ pcxl_dma_init(void)

__initcall(pcxl_dma_init);

-static void *pcxl_dma_alloc(struct device *dev, size_t size,
- dma_addr_t *dma_handle, gfp_t flag, unsigned long attrs)
+void *arch_dma_alloc(struct device *dev, size_t size,
+ dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
{
unsigned long vaddr;
unsigned long paddr;
int order;

+ if (boot_cpu_data.cpu_type != pcxl2 && boot_cpu_data.cpu_type != pcxl)
+ return NULL;
+
order = get_order(size);
size = 1 << (order + PAGE_SHIFT);
vaddr = pcxl_alloc_range(size);
- paddr = __get_free_pages(flag | __GFP_ZERO, order);
+ paddr = __get_free_pages(gfp | __GFP_ZERO, order);
flush_kernel_dcache_range(paddr, size);
paddr = __pa(paddr);
map_uncached_pages(vaddr, size, paddr);
@@ -421,44 +424,19 @@ static void *pcxl_dma_alloc(struct device *dev, size_t size,
return (void *)vaddr;
}

-static void *pcx_dma_alloc(struct device *dev, size_t size,
- dma_addr_t *dma_handle, gfp_t flag, unsigned long attrs)
-{
- void *addr;
-
- if ((attrs & DMA_ATTR_NON_CONSISTENT) == 0)
- return NULL;
-
- addr = (void *)__get_free_pages(flag | __GFP_ZERO, get_order(size));
- if (addr)
- *dma_handle = (dma_addr_t)virt_to_phys(addr);
-
- return addr;
-}
-
-void *arch_dma_alloc(struct device *dev, size_t size,
- dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
-{
-
- if (boot_cpu_data.cpu_type == pcxl2 || boot_cpu_data.cpu_type == pcxl)
- return pcxl_dma_alloc(dev, size, dma_handle, gfp, attrs);
- else
- return pcx_dma_alloc(dev, size, dma_handle, gfp, attrs);
-}
-
void arch_dma_free(struct device *dev, size_t size, void *vaddr,
dma_addr_t dma_handle, unsigned long attrs)
{
int order = get_order(size);

- if (boot_cpu_data.cpu_type == pcxl2 || boot_cpu_data.cpu_type == pcxl) {
- size = 1 << (order + PAGE_SHIFT);
- unmap_uncached_pages((unsigned long)vaddr, size);
- pcxl_free_range((unsigned long)vaddr, size);
+ WARN_ON_ONCE(boot_cpu_data.cpu_type != pcxl2 &&
+ boot_cpu_data.cpu_type != pcxl);

- vaddr = __va(dma_handle);
- }
- free_pages((unsigned long)vaddr, get_order(size));
+ size = 1 << (order + PAGE_SHIFT);
+ unmap_uncached_pages((unsigned long)vaddr, size);
+ pcxl_free_range((unsigned long)vaddr, size);
+
+ free_pages((unsigned long)__va(dma_handle), order);
}

void arch_sync_dma_for_device(struct device *dev, phys_addr_t paddr,
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index c2893713bf80..fc354f4f490b 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -191,7 +191,7 @@ void *dma_direct_alloc(struct device *dev, size_t size,
dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
{
if (!IS_ENABLED(CONFIG_ARCH_HAS_UNCACHED_SEGMENT) &&
- !dev_is_dma_coherent(dev))
+ dma_alloc_need_uncached(dev, attrs))
return arch_dma_alloc(dev, size, dma_handle, gfp, attrs);
return dma_direct_alloc_pages(dev, size, dma_handle, gfp, attrs);
}
@@ -200,7 +200,7 @@ void dma_direct_free(struct device *dev, size_t size,
void *cpu_addr, dma_addr_t dma_addr, unsigned long attrs)
{
if (!IS_ENABLED(CONFIG_ARCH_HAS_UNCACHED_SEGMENT) &&
- !dev_is_dma_coherent(dev))
+ dma_alloc_need_uncached(dev, attrs))
arch_dma_free(dev, size, cpu_addr, dma_addr, attrs);
else
dma_direct_free_pages(dev, size, cpu_addr, dma_addr, attrs);
--
2.20.1