dma-mapping: always use VM_DMA_COHERENT for generic DMA remap

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@lst.de>

5 files changed, 21 insertions, 28 deletions

diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index aec31f9b918b..fd02c982e36a 100644
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c
@@ -343,13 +343,12 @@ 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);
+        return dma_common_contiguous_remap(page, size, prot, caller);
 }
 
 static void __dma_free_remap(void *cpu_addr, size_t size)
 {
-        dma_common_free_remap(cpu_addr, size, VM_DMA_COHERENT);
+        dma_common_free_remap(cpu_addr, size);
 }
 
 #define DEFAULT_DMA_COHERENT_POOL_SIZE  SZ_256K
@@ -1365,8 +1364,7 @@ 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);
+        return dma_common_pages_remap(pages, size, prot, caller);
 }
 
 /*
@@ -1609,7 +1607,7 @@ 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 65f05776d827..154979d62b73 100644
--- a/arch/xtensa/kernel/pci-dma.c
+++ b/arch/xtensa/kernel/pci-dma.c
@@ -167,7 +167,7 @@ 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) {
@@ -192,7 +192,7 @@ 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 ef407e4eccde..949e341bf2f3 100644
--- a/drivers/iommu/dma-iommu.c
+++ b/drivers/iommu/dma-iommu.c
@@ -617,7 +617,7 @@ 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;
@@ -941,7 +941,7 @@ 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);
@@ -979,7 +979,7 @@ static void *iommu_dma_alloc_pages(struct device *dev, size_t size,
                 pgprot_t prot = dma_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 80063b0fdea8..86223bc24d82 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h
@@ -627,13 +627,11 @@ 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);
 
 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);
diff --git a/kernel/dma/remap.c b/kernel/dma/remap.c
index 838123f79639..f6b90521a7e4 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;
         }
@@ -136,7 +133,7 @@ static int __init dma_atomic_pool_init(void)
         if (!atomic_pool)
                 goto free_page;
 
-        addr = dma_common_contiguous_remap(page, atomic_pool_size, VM_USERMAP,
+        addr = dma_common_contiguous_remap(page, atomic_pool_size,
                                            pgprot_dmacoherent(PAGE_KERNEL),
                                            __builtin_return_address(0));
         if (!addr)
@@ -153,7 +150,7 @@ static int __init dma_atomic_pool_init(void)
         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;
@@ -228,7 +225,7 @@ void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
         arch_dma_prep_coherent(page, size);
 
         /* create a coherent mapping */
-        ret = dma_common_contiguous_remap(page, size, VM_USERMAP,
+        ret = dma_common_contiguous_remap(page, size,
                         dma_pgprot(dev, PAGE_KERNEL, attrs),
                         __builtin_return_address(0));
         if (!ret) {