[PATCH 2/3] dma-mapping: always use VM_DMA_COHERENT for generic DMA remap
Christoph Hellwig
hch at lst.de
Tue Jun 4 06:55:03 UTC 2019
Currently the generic dma remap allocator gets a vm_flags passed by
the caller that is a little confusing. We just introduced a generic
vmalloc-level flag to identify the dma coherent allocations, so use
that everywhere and remove the now pointless argument.
Signed-off-by: Christoph Hellwig <hch at lst.de>
---
arch/arm/mm/dma-mapping.c | 37 +++++++-----------------------------
arch/xtensa/kernel/pci-dma.c | 4 ++--
drivers/iommu/dma-iommu.c | 6 +++---
include/linux/dma-mapping.h | 6 ++----
kernel/dma/remap.c | 25 +++++++++++-------------
5 files changed, 25 insertions(+), 53 deletions(-)
diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index e197b028e341..647fd25d2aba 100644
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c
@@ -356,19 +356,6 @@ static void *__alloc_remap_buffer(struct device *dev, size_t size, gfp_t gfp,
pgprot_t prot, struct page **ret_page,
const void *caller, bool want_vaddr);
-static void *
-__dma_alloc_remap(struct page *page, size_t size, gfp_t gfp, pgprot_t prot,
- const void *caller)
-{
- return dma_common_contiguous_remap(page, size, VM_DMA_COHERENT,
- prot, caller);
-}
-
-static void __dma_free_remap(void *cpu_addr, size_t size)
-{
- dma_common_free_remap(cpu_addr, size, VM_DMA_COHERENT);
-}
-
#define DEFAULT_DMA_COHERENT_POOL_SIZE SZ_256K
static struct gen_pool *atomic_pool __ro_after_init;
@@ -525,7 +512,7 @@ static void *__alloc_remap_buffer(struct device *dev, size_t size, gfp_t gfp,
if (!want_vaddr)
goto out;
- ptr = __dma_alloc_remap(page, size, gfp, prot, caller);
+ ptr = dma_common_contiguous_remap(page, size, gfp, prot, caller);
if (!ptr) {
__dma_free_buffer(page, size);
return NULL;
@@ -592,7 +579,8 @@ static void *__alloc_from_contiguous(struct device *dev, size_t size,
goto out;
if (PageHighMem(page)) {
- ptr = __dma_alloc_remap(page, size, GFP_KERNEL, prot, caller);
+ ptr = dma_common_contiguous_remap(page, size, GFP_KERNEL, prot,
+ caller);
if (!ptr) {
dma_release_from_contiguous(dev, page, count);
return NULL;
@@ -612,7 +600,7 @@ static void __free_from_contiguous(struct device *dev, struct page *page,
{
if (want_vaddr) {
if (PageHighMem(page))
- __dma_free_remap(cpu_addr, size);
+ dma_common_free_remap(cpu_addr, size);
else
__dma_remap(page, size, PAGE_KERNEL);
}
@@ -704,7 +692,7 @@ static void *remap_allocator_alloc(struct arm_dma_alloc_args *args,
static void remap_allocator_free(struct arm_dma_free_args *args)
{
if (args->want_vaddr)
- __dma_free_remap(args->cpu_addr, args->size);
+ dma_common_free_remap(args->cpu_addr, args->size);
__dma_free_buffer(args->page, args->size);
}
@@ -1374,17 +1362,6 @@ static int __iommu_free_buffer(struct device *dev, struct page **pages,
return 0;
}
-/*
- * Create a CPU mapping for a specified pages
- */
-static void *
-__iommu_alloc_remap(struct page **pages, size_t size, gfp_t gfp, pgprot_t prot,
- const void *caller)
-{
- return dma_common_pages_remap(pages, size, VM_DMA_COHERENT, prot,
- caller);
-}
-
/*
* Create a mapping in device IO address space for specified pages
*/
@@ -1541,7 +1518,7 @@ static void *__arm_iommu_alloc_attrs(struct device *dev, size_t size,
if (attrs & DMA_ATTR_NO_KERNEL_MAPPING)
return pages;
- addr = __iommu_alloc_remap(pages, size, gfp, prot,
+ addr = dma_common_pages_remap(pages, size, gfp, prot,
__builtin_return_address(0));
if (!addr)
goto err_mapping;
@@ -1625,7 +1602,7 @@ void __arm_iommu_free_attrs(struct device *dev, size_t size, void *cpu_addr,
}
if ((attrs & DMA_ATTR_NO_KERNEL_MAPPING) == 0)
- dma_common_free_remap(cpu_addr, size, VM_DMA_COHERENT);
+ dma_common_free_remap(cpu_addr, size);
__iommu_remove_mapping(dev, handle, size);
__iommu_free_buffer(dev, pages, size, attrs);
diff --git a/arch/xtensa/kernel/pci-dma.c b/arch/xtensa/kernel/pci-dma.c
index 9171bff76fc4..81c1def6b5a2 100644
--- a/arch/xtensa/kernel/pci-dma.c
+++ b/arch/xtensa/kernel/pci-dma.c
@@ -175,7 +175,7 @@ void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *handle,
if (PageHighMem(page)) {
void *p;
- p = dma_common_contiguous_remap(page, size, VM_MAP,
+ p = dma_common_contiguous_remap(page, size,
pgprot_noncached(PAGE_KERNEL),
__builtin_return_address(0));
if (!p) {
@@ -202,7 +202,7 @@ void arch_dma_free(struct device *dev, size_t size, void *vaddr,
page = virt_to_page(platform_vaddr_to_cached(vaddr));
} else {
#ifdef CONFIG_MMU
- dma_common_free_remap(vaddr, size, VM_MAP);
+ dma_common_free_remap(vaddr, size);
#endif
page = pfn_to_page(PHYS_PFN(dma_to_phys(dev, dma_handle)));
}
diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
index 0dee374fc64a..cea561897086 100644
--- a/drivers/iommu/dma-iommu.c
+++ b/drivers/iommu/dma-iommu.c
@@ -619,7 +619,7 @@ static void *iommu_dma_alloc_remap(struct device *dev, size_t size,
< size)
goto out_free_sg;
- vaddr = dma_common_pages_remap(pages, size, VM_USERMAP, prot,
+ vaddr = dma_common_pages_remap(pages, size, prot,
__builtin_return_address(0));
if (!vaddr)
goto out_unmap;
@@ -943,7 +943,7 @@ static void __iommu_dma_free(struct device *dev, size_t size, void *cpu_addr)
pages = __iommu_dma_get_pages(cpu_addr);
if (!pages)
page = vmalloc_to_page(cpu_addr);
- dma_common_free_remap(cpu_addr, alloc_size, VM_USERMAP);
+ dma_common_free_remap(cpu_addr, alloc_size);
} else {
/* Lowmem means a coherent atomic or CMA allocation */
page = virt_to_page(cpu_addr);
@@ -983,7 +983,7 @@ static void *iommu_dma_alloc_pages(struct device *dev, size_t size,
pgprot_t prot = arch_dma_mmap_pgprot(dev, PAGE_KERNEL, attrs);
cpu_addr = dma_common_contiguous_remap(page, alloc_size,
- VM_USERMAP, prot, __builtin_return_address(0));
+ prot, __builtin_return_address(0));
if (!cpu_addr)
goto out_free_pages;
diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index 6309a721394b..ac320b7cacfd 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h
@@ -616,13 +616,11 @@ extern int dma_common_mmap(struct device *dev, struct vm_area_struct *vma,
unsigned long attrs);
void *dma_common_contiguous_remap(struct page *page, size_t size,
- unsigned long vm_flags,
pgprot_t prot, const void *caller);
void *dma_common_pages_remap(struct page **pages, size_t size,
- unsigned long vm_flags, pgprot_t prot,
- const void *caller);
-void dma_common_free_remap(void *cpu_addr, size_t size, unsigned long vm_flags);
+ pgprot_t prot, const void *caller);
+void dma_common_free_remap(void *cpu_addr, size_t size);
int __init dma_atomic_pool_init(gfp_t gfp, pgprot_t prot);
bool dma_in_atomic_pool(void *start, size_t size);
diff --git a/kernel/dma/remap.c b/kernel/dma/remap.c
index 7a723194ecbe..51958d21c810 100644
--- a/kernel/dma/remap.c
+++ b/kernel/dma/remap.c
@@ -12,12 +12,11 @@
#include <linux/vmalloc.h>
static struct vm_struct *__dma_common_pages_remap(struct page **pages,
- size_t size, unsigned long vm_flags, pgprot_t prot,
- const void *caller)
+ size_t size, pgprot_t prot, const void *caller)
{
struct vm_struct *area;
- area = get_vm_area_caller(size, vm_flags, caller);
+ area = get_vm_area_caller(size, VM_DMA_COHERENT, caller);
if (!area)
return NULL;
@@ -34,12 +33,11 @@ static struct vm_struct *__dma_common_pages_remap(struct page **pages,
* Cannot be used in non-sleeping contexts
*/
void *dma_common_pages_remap(struct page **pages, size_t size,
- unsigned long vm_flags, pgprot_t prot,
- const void *caller)
+ pgprot_t prot, const void *caller)
{
struct vm_struct *area;
- area = __dma_common_pages_remap(pages, size, vm_flags, prot, caller);
+ area = __dma_common_pages_remap(pages, size, prot, caller);
if (!area)
return NULL;
@@ -53,7 +51,6 @@ void *dma_common_pages_remap(struct page **pages, size_t size,
* Cannot be used in non-sleeping contexts
*/
void *dma_common_contiguous_remap(struct page *page, size_t size,
- unsigned long vm_flags,
pgprot_t prot, const void *caller)
{
int i;
@@ -67,7 +64,7 @@ void *dma_common_contiguous_remap(struct page *page, size_t size,
for (i = 0; i < (size >> PAGE_SHIFT); i++)
pages[i] = nth_page(page, i);
- area = __dma_common_pages_remap(pages, size, vm_flags, prot, caller);
+ area = __dma_common_pages_remap(pages, size, prot, caller);
kfree(pages);
@@ -79,11 +76,11 @@ void *dma_common_contiguous_remap(struct page *page, size_t size,
/*
* Unmaps a range previously mapped by dma_common_*_remap
*/
-void dma_common_free_remap(void *cpu_addr, size_t size, unsigned long vm_flags)
+void dma_common_free_remap(void *cpu_addr, size_t size)
{
struct vm_struct *area = find_vm_area(cpu_addr);
- if (!area || (area->flags & vm_flags) != vm_flags) {
+ if (!area || area->flags != VM_DMA_COHERENT) {
WARN(1, "trying to free invalid coherent area: %p\n", cpu_addr);
return;
}
@@ -127,8 +124,8 @@ int __init dma_atomic_pool_init(gfp_t gfp, pgprot_t prot)
if (!atomic_pool)
goto free_page;
- addr = dma_common_contiguous_remap(page, atomic_pool_size, VM_USERMAP,
- prot, __builtin_return_address(0));
+ addr = dma_common_contiguous_remap(page, atomic_pool_size, prot,
+ __builtin_return_address(0));
if (!addr)
goto destroy_genpool;
@@ -143,7 +140,7 @@ int __init dma_atomic_pool_init(gfp_t gfp, pgprot_t prot)
return 0;
remove_mapping:
- dma_common_free_remap(addr, atomic_pool_size, VM_USERMAP);
+ dma_common_free_remap(addr, atomic_pool_size);
destroy_genpool:
gen_pool_destroy(atomic_pool);
atomic_pool = NULL;
@@ -220,7 +217,7 @@ void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
}
/* create a coherent mapping */
- ret = dma_common_contiguous_remap(page, size, VM_USERMAP,
+ ret = dma_common_contiguous_remap(page, size,
arch_dma_mmap_pgprot(dev, PAGE_KERNEL, attrs),
__builtin_return_address(0));
if (!ret) {
--
2.20.1
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