[rfc 1/6] dma-mapping: pass device to atomic allocation functions

From: David Rientjes
Date: Sun Mar 01 2020 - 19:05:14 EST


This augments the dma_{alloc,free}_from_pool() functions with a pointer
to the struct device of the allocation. This introduces no functional
change and will be used later to determine the optimal gfp mask to
allocate memory from.

dma_in_atomic_pool() is not used outside kernel/dma/remap.c, so remove
its declaration from the header file.

Signed-off-by: David Rientjes <rientjes@xxxxxxxxxx>
---
drivers/iommu/dma-iommu.c | 5 +++--
include/linux/dma-mapping.h | 6 +++---
kernel/dma/direct.c | 4 ++--
kernel/dma/remap.c | 9 +++++----
4 files changed, 13 insertions(+), 11 deletions(-)

diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
--- a/drivers/iommu/dma-iommu.c
+++ b/drivers/iommu/dma-iommu.c
@@ -952,7 +952,7 @@ static void __iommu_dma_free(struct device *dev, size_t size, void *cpu_addr)

/* Non-coherent atomic allocation? Easy */
if (IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) &&
- dma_free_from_pool(cpu_addr, alloc_size))
+ dma_free_from_pool(dev, cpu_addr, alloc_size))
return;

if (IS_ENABLED(CONFIG_DMA_REMAP) && is_vmalloc_addr(cpu_addr)) {
@@ -1035,7 +1035,8 @@ static void *iommu_dma_alloc(struct device *dev, size_t size,

if (IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) &&
!gfpflags_allow_blocking(gfp) && !coherent)
- cpu_addr = dma_alloc_from_pool(PAGE_ALIGN(size), &page, gfp);
+ cpu_addr = dma_alloc_from_pool(dev, PAGE_ALIGN(size), &page,
+ gfp);
else
cpu_addr = iommu_dma_alloc_pages(dev, size, &page, gfp, attrs);
if (!cpu_addr)
diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h
@@ -630,9 +630,9 @@ void *dma_common_pages_remap(struct page **pages, size_t size,
pgprot_t prot, const void *caller);
void dma_common_free_remap(void *cpu_addr, size_t size);

-bool dma_in_atomic_pool(void *start, size_t size);
-void *dma_alloc_from_pool(size_t size, struct page **ret_page, gfp_t flags);
-bool dma_free_from_pool(void *start, size_t size);
+void *dma_alloc_from_pool(struct device *dev, size_t size,
+ struct page **ret_page, gfp_t flags);
+bool dma_free_from_pool(struct device *dev, void *start, size_t size);

int
dma_common_get_sgtable(struct device *dev, struct sg_table *sgt, void *cpu_addr,
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -127,7 +127,7 @@ void *dma_direct_alloc_pages(struct device *dev, size_t size,
if (IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) &&
dma_alloc_need_uncached(dev, attrs) &&
!gfpflags_allow_blocking(gfp)) {
- ret = dma_alloc_from_pool(PAGE_ALIGN(size), &page, gfp);
+ ret = dma_alloc_from_pool(dev, PAGE_ALIGN(size), &page, gfp);
if (!ret)
return NULL;
goto done;
@@ -210,7 +210,7 @@ void dma_direct_free_pages(struct device *dev, size_t size, void *cpu_addr,
}

if (IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) &&
- dma_free_from_pool(cpu_addr, PAGE_ALIGN(size)))
+ dma_free_from_pool(dev, cpu_addr, PAGE_ALIGN(size)))
return;

if (force_dma_unencrypted(dev))
diff --git a/kernel/dma/remap.c b/kernel/dma/remap.c
--- a/kernel/dma/remap.c
+++ b/kernel/dma/remap.c
@@ -173,7 +173,7 @@ static int __init dma_atomic_pool_init(void)
}
postcore_initcall(dma_atomic_pool_init);

-bool dma_in_atomic_pool(void *start, size_t size)
+static bool dma_in_atomic_pool(struct device *dev, void *start, size_t size)
{
if (unlikely(!atomic_pool))
return false;
@@ -181,7 +181,8 @@ bool dma_in_atomic_pool(void *start, size_t size)
return gen_pool_has_addr(atomic_pool, (unsigned long)start, size);
}

-void *dma_alloc_from_pool(size_t size, struct page **ret_page, gfp_t flags)
+void *dma_alloc_from_pool(struct device *dev, size_t size,
+ struct page **ret_page, gfp_t flags)
{
unsigned long val;
void *ptr = NULL;
@@ -203,9 +204,9 @@ void *dma_alloc_from_pool(size_t size, struct page **ret_page, gfp_t flags)
return ptr;
}

-bool dma_free_from_pool(void *start, size_t size)
+bool dma_free_from_pool(struct device *dev, void *start, size_t size)
{
- if (!dma_in_atomic_pool(start, size))
+ if (!dma_in_atomic_pool(dev, start, size))
return false;
gen_pool_free(atomic_pool, (unsigned long)start, size);
return true;