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-rw-r--r--include/linux/dma-map-ops.h13
-rw-r--r--kernel/dma/direct.c100
2 files changed, 39 insertions, 74 deletions
diff --git a/include/linux/dma-map-ops.h b/include/linux/dma-map-ops.h
index 33c6e24707a9..8029f7e04145 100644
--- a/include/linux/dma-map-ops.h
+++ b/include/linux/dma-map-ops.h
@@ -219,19 +219,6 @@ static inline bool dev_is_dma_coherent(struct device *dev)
}
#endif /* CONFIG_ARCH_HAS_DMA_COHERENCE_H */
-/*
- * Check if an allocation needs to be marked uncached to be coherent.
- */
-static __always_inline bool dma_alloc_need_uncached(struct device *dev,
- unsigned long attrs)
-{
- if (dev_is_dma_coherent(dev))
- return false;
- if (attrs & DMA_ATTR_NO_KERNEL_MAPPING)
- return false;
- return true;
-}
-
void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
gfp_t gfp, unsigned long attrs);
void arch_dma_free(struct device *dev, size_t size, void *cpu_addr,
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index eddcb70251c9..b92d08e65999 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -75,39 +75,6 @@ static bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size)
min_not_zero(dev->coherent_dma_mask, dev->bus_dma_limit);
}
-/*
- * Decrypting memory is allowed to block, so if this device requires
- * unencrypted memory it must come from atomic pools.
- */
-static inline bool dma_should_alloc_from_pool(struct device *dev, gfp_t gfp,
- unsigned long attrs)
-{
- if (!IS_ENABLED(CONFIG_DMA_COHERENT_POOL))
- return false;
- if (gfpflags_allow_blocking(gfp))
- return false;
- if (force_dma_unencrypted(dev))
- return true;
- if (!IS_ENABLED(CONFIG_DMA_DIRECT_REMAP))
- return false;
- if (dma_alloc_need_uncached(dev, attrs))
- return true;
- return false;
-}
-
-static inline bool dma_should_free_from_pool(struct device *dev,
- unsigned long attrs)
-{
- if (IS_ENABLED(CONFIG_DMA_COHERENT_POOL))
- return true;
- if ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) &&
- !force_dma_unencrypted(dev))
- return false;
- if (IS_ENABLED(CONFIG_DMA_DIRECT_REMAP))
- return true;
- return false;
-}
-
static struct page *__dma_direct_alloc_pages(struct device *dev, size_t size,
gfp_t gfp)
{
@@ -170,35 +137,45 @@ void *dma_direct_alloc(struct device *dev, size_t size,
void *ret;
int err;
- if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_SET_UNCACHED) &&
- !IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) &&
- dma_alloc_need_uncached(dev, attrs))
- return arch_dma_alloc(dev, size, dma_handle, gfp, attrs);
-
size = PAGE_ALIGN(size);
if (attrs & DMA_ATTR_NO_WARN)
gfp |= __GFP_NOWARN;
- if (dma_should_alloc_from_pool(dev, gfp, attrs))
- return dma_direct_alloc_from_pool(dev, size, dma_handle, gfp);
-
- /* we always manually zero the memory once we are done */
- page = __dma_direct_alloc_pages(dev, size, gfp & ~__GFP_ZERO);
- if (!page)
- return NULL;
-
if ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) &&
!force_dma_unencrypted(dev)) {
+ page = __dma_direct_alloc_pages(dev, size, gfp & ~__GFP_ZERO);
+ if (!page)
+ return NULL;
/* remove any dirty cache lines on the kernel alias */
if (!PageHighMem(page))
arch_dma_prep_coherent(page, size);
+ *dma_handle = phys_to_dma_direct(dev, page_to_phys(page));
/* return the page pointer as the opaque cookie */
- ret = page;
- goto done;
+ return page;
}
+ if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_SET_UNCACHED) &&
+ !IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) &&
+ !dev_is_dma_coherent(dev))
+ return arch_dma_alloc(dev, size, dma_handle, gfp, attrs);
+
+ /*
+ * Remapping or decrypting memory may block. If either is required and
+ * we can't block, allocate the memory from the atomic pools.
+ */
+ if (IS_ENABLED(CONFIG_DMA_COHERENT_POOL) &&
+ !gfpflags_allow_blocking(gfp) &&
+ (force_dma_unencrypted(dev) ||
+ (IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) && !dev_is_dma_coherent(dev))))
+ return dma_direct_alloc_from_pool(dev, size, dma_handle, gfp);
+
+ /* we always manually zero the memory once we are done */
+ page = __dma_direct_alloc_pages(dev, size, gfp & ~__GFP_ZERO);
+ if (!page)
+ return NULL;
+
if ((IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) &&
- dma_alloc_need_uncached(dev, attrs)) ||
+ !dev_is_dma_coherent(dev)) ||
(IS_ENABLED(CONFIG_DMA_REMAP) && PageHighMem(page))) {
/* remove any dirty cache lines on the kernel alias */
arch_dma_prep_coherent(page, size);
@@ -241,7 +218,7 @@ void *dma_direct_alloc(struct device *dev, size_t size,
memset(ret, 0, size);
if (IS_ENABLED(CONFIG_ARCH_HAS_DMA_SET_UNCACHED) &&
- dma_alloc_need_uncached(dev, attrs)) {
+ !dev_is_dma_coherent(dev)) {
arch_dma_prep_coherent(page, size);
ret = arch_dma_set_uncached(ret, size);
if (IS_ERR(ret))
@@ -269,25 +246,25 @@ void dma_direct_free(struct device *dev, size_t size,
{
unsigned int page_order = get_order(size);
+ if ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) &&
+ !force_dma_unencrypted(dev)) {
+ /* cpu_addr is a struct page cookie, not a kernel address */
+ dma_free_contiguous(dev, cpu_addr, size);
+ return;
+ }
+
if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_SET_UNCACHED) &&
!IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) &&
- dma_alloc_need_uncached(dev, attrs)) {
+ !dev_is_dma_coherent(dev)) {
arch_dma_free(dev, size, cpu_addr, dma_addr, attrs);
return;
}
/* If cpu_addr is not from an atomic pool, dma_free_from_pool() fails */
- if (dma_should_free_from_pool(dev, attrs) &&
+ if (IS_ENABLED(CONFIG_DMA_COHERENT_POOL) &&
dma_free_from_pool(dev, cpu_addr, PAGE_ALIGN(size)))
return;
- if ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) &&
- !force_dma_unencrypted(dev)) {
- /* cpu_addr is a struct page cookie, not a kernel address */
- dma_free_contiguous(dev, cpu_addr, size);
- return;
- }
-
if (force_dma_unencrypted(dev))
set_memory_encrypted((unsigned long)cpu_addr, 1 << page_order);
@@ -305,7 +282,8 @@ struct page *dma_direct_alloc_pages(struct device *dev, size_t size,
struct page *page;
void *ret;
- if (dma_should_alloc_from_pool(dev, gfp, 0))
+ if (IS_ENABLED(CONFIG_DMA_COHERENT_POOL) &&
+ force_dma_unencrypted(dev) && !gfpflags_allow_blocking(gfp))
return dma_direct_alloc_from_pool(dev, size, dma_handle, gfp);
page = __dma_direct_alloc_pages(dev, size, gfp);
@@ -344,7 +322,7 @@ void dma_direct_free_pages(struct device *dev, size_t size,
void *vaddr = page_address(page);
/* If cpu_addr is not from an atomic pool, dma_free_from_pool() fails */
- if (dma_should_free_from_pool(dev, 0) &&
+ if (IS_ENABLED(CONFIG_DMA_COHERENT_POOL) &&
dma_free_from_pool(dev, vaddr, size))
return;