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authorLinus Torvalds <torvalds@linux-foundation.org>2019-07-12 15:13:55 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2019-07-12 15:13:55 -0700
commit9e3a25dc992dd9f3170fb643bdd95da5ca9c5576 (patch)
treef636ae59fa83c83e837a6668b2693175a6e39f3a /kernel/dma
parent9787aed57dd33ba5c15a713c2c50e78baeb5052d (diff)
parent15ffe5e1acf5fe1512e98b20702e46ce9f25e2f7 (diff)
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Merge tag 'dma-mapping-5.3' of git://git.infradead.org/users/hch/dma-mapping
Pull dma-mapping updates from Christoph Hellwig: - move the USB special case that bounced DMA through a device bar into the USB code instead of handling it in the common DMA code (Laurentiu Tudor and Fredrik Noring) - don't dip into the global CMA pool for single page allocations (Nicolin Chen) - fix a crash when allocating memory for the atomic pool failed during boot (Florian Fainelli) - move support for MIPS-style uncached segments to the common code and use that for MIPS and nios2 (me) - make support for DMA_ATTR_NON_CONSISTENT and DMA_ATTR_NO_KERNEL_MAPPING generic (me) - convert nds32 to the generic remapping allocator (me) * tag 'dma-mapping-5.3' of git://git.infradead.org/users/hch/dma-mapping: (29 commits) dma-mapping: mark dma_alloc_need_uncached as __always_inline MIPS: only select ARCH_HAS_UNCACHED_SEGMENT for non-coherent platforms usb: host: Fix excessive alignment restriction for local memory allocations lib/genalloc.c: Add algorithm, align and zeroed family of DMA allocators nios2: use the generic uncached segment support in dma-direct nds32: use the generic remapping allocator for coherent DMA allocations arc: use the generic remapping allocator for coherent DMA allocations dma-direct: handle DMA_ATTR_NO_KERNEL_MAPPING in common code dma-direct: handle DMA_ATTR_NON_CONSISTENT in common code dma-mapping: add a dma_alloc_need_uncached helper openrisc: remove the partial DMA_ATTR_NON_CONSISTENT support arc: remove the partial DMA_ATTR_NON_CONSISTENT support arm-nommu: remove the partial DMA_ATTR_NON_CONSISTENT support ARM: dma-mapping: allow larger DMA mask than supported dma-mapping: truncate dma masks to what dma_addr_t can hold iommu/dma: Apply dma_{alloc,free}_contiguous functions dma-remap: Avoid de-referencing NULL atomic_pool MIPS: use the generic uncached segment support in dma-direct dma-direct: provide generic support for uncached kernel segments au1100fb: fix DMA API abuse ...
Diffstat (limited to 'kernel/dma')
-rw-r--r--kernel/dma/contiguous.c56
-rw-r--r--kernel/dma/direct.c55
-rw-r--r--kernel/dma/mapping.c12
-rw-r--r--kernel/dma/remap.c16
4 files changed, 106 insertions, 33 deletions
diff --git a/kernel/dma/contiguous.c b/kernel/dma/contiguous.c
index b2a87905846d..bfc0c17f2a3d 100644
--- a/kernel/dma/contiguous.c
+++ b/kernel/dma/contiguous.c
@@ -214,6 +214,62 @@ bool dma_release_from_contiguous(struct device *dev, struct page *pages,
return cma_release(dev_get_cma_area(dev), pages, count);
}
+/**
+ * dma_alloc_contiguous() - allocate contiguous pages
+ * @dev: Pointer to device for which the allocation is performed.
+ * @size: Requested allocation size.
+ * @gfp: Allocation flags.
+ *
+ * This function allocates contiguous memory buffer for specified device. It
+ * first tries to use device specific contiguous memory area if available or
+ * the default global one, then tries a fallback allocation of normal pages.
+ *
+ * Note that it byapss one-page size of allocations from the global area as
+ * the addresses within one page are always contiguous, so there is no need
+ * to waste CMA pages for that kind; it also helps reduce fragmentations.
+ */
+struct page *dma_alloc_contiguous(struct device *dev, size_t size, gfp_t gfp)
+{
+ int node = dev ? dev_to_node(dev) : NUMA_NO_NODE;
+ size_t count = PAGE_ALIGN(size) >> PAGE_SHIFT;
+ size_t align = get_order(PAGE_ALIGN(size));
+ struct page *page = NULL;
+ struct cma *cma = NULL;
+
+ if (dev && dev->cma_area)
+ cma = dev->cma_area;
+ else if (count > 1)
+ cma = dma_contiguous_default_area;
+
+ /* CMA can be used only in the context which permits sleeping */
+ if (cma && gfpflags_allow_blocking(gfp)) {
+ align = min_t(size_t, align, CONFIG_CMA_ALIGNMENT);
+ page = cma_alloc(cma, count, align, gfp & __GFP_NOWARN);
+ }
+
+ /* Fallback allocation of normal pages */
+ if (!page)
+ page = alloc_pages_node(node, gfp, align);
+ return page;
+}
+
+/**
+ * dma_free_contiguous() - release allocated pages
+ * @dev: Pointer to device for which the pages were allocated.
+ * @page: Pointer to the allocated pages.
+ * @size: Size of allocated pages.
+ *
+ * This function releases memory allocated by dma_alloc_contiguous(). As the
+ * cma_release returns false when provided pages do not belong to contiguous
+ * area and true otherwise, this function then does a fallback __free_pages()
+ * upon a false-return.
+ */
+void dma_free_contiguous(struct device *dev, struct page *page, size_t size)
+{
+ if (!cma_release(dev_get_cma_area(dev), page, size >> PAGE_SHIFT))
+ __free_pages(page, get_order(size));
+}
+
/*
* Support for reserved memory regions defined in device tree
*/
diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c
index 2c2772e9702a..b90e1aede743 100644
--- a/kernel/dma/direct.c
+++ b/kernel/dma/direct.c
@@ -96,8 +96,6 @@ static bool dma_coherent_ok(struct device *dev, phys_addr_t phys, size_t size)
struct page *__dma_direct_alloc_pages(struct device *dev, size_t size,
dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
{
- unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
- int page_order = get_order(size);
struct page *page = NULL;
u64 phys_mask;
@@ -109,20 +107,9 @@ struct page *__dma_direct_alloc_pages(struct device *dev, size_t size,
gfp |= __dma_direct_optimal_gfp_mask(dev, dev->coherent_dma_mask,
&phys_mask);
again:
- /* CMA can be used only in the context which permits sleeping */
- if (gfpflags_allow_blocking(gfp)) {
- page = dma_alloc_from_contiguous(dev, count, page_order,
- gfp & __GFP_NOWARN);
- if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) {
- dma_release_from_contiguous(dev, page, count);
- page = NULL;
- }
- }
- if (!page)
- page = alloc_pages_node(dev_to_node(dev), gfp, page_order);
-
+ page = dma_alloc_contiguous(dev, size, gfp);
if (page && !dma_coherent_ok(dev, page_to_phys(page), size)) {
- __free_pages(page, page_order);
+ dma_free_contiguous(dev, page, size);
page = NULL;
if (IS_ENABLED(CONFIG_ZONE_DMA32) &&
@@ -151,10 +138,18 @@ void *dma_direct_alloc_pages(struct device *dev, size_t size,
if (!page)
return NULL;
+ if (attrs & DMA_ATTR_NO_KERNEL_MAPPING) {
+ /* remove any dirty cache lines on the kernel alias */
+ if (!PageHighMem(page))
+ arch_dma_prep_coherent(page, size);
+ /* return the page pointer as the opaque cookie */
+ return page;
+ }
+
if (PageHighMem(page)) {
/*
* Depending on the cma= arguments and per-arch setup
- * dma_alloc_from_contiguous could return highmem pages.
+ * dma_alloc_contiguous could return highmem pages.
* Without remapping there is no way to return them here,
* so log an error and fail.
*/
@@ -171,15 +166,19 @@ void *dma_direct_alloc_pages(struct device *dev, size_t size,
*dma_handle = phys_to_dma(dev, page_to_phys(page));
}
memset(ret, 0, size);
+
+ if (IS_ENABLED(CONFIG_ARCH_HAS_UNCACHED_SEGMENT) &&
+ dma_alloc_need_uncached(dev, attrs)) {
+ arch_dma_prep_coherent(page, size);
+ ret = uncached_kernel_address(ret);
+ }
+
return ret;
}
void __dma_direct_free_pages(struct device *dev, size_t size, struct page *page)
{
- unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
-
- if (!dma_release_from_contiguous(dev, page, count))
- __free_pages(page, get_order(size));
+ dma_free_contiguous(dev, page, size);
}
void dma_direct_free_pages(struct device *dev, size_t size, void *cpu_addr,
@@ -187,15 +186,26 @@ void dma_direct_free_pages(struct device *dev, size_t size, void *cpu_addr,
{
unsigned int page_order = get_order(size);
+ if (attrs & DMA_ATTR_NO_KERNEL_MAPPING) {
+ /* cpu_addr is a struct page cookie, not a kernel address */
+ __dma_direct_free_pages(dev, size, cpu_addr);
+ return;
+ }
+
if (force_dma_unencrypted())
set_memory_encrypted((unsigned long)cpu_addr, 1 << page_order);
+
+ if (IS_ENABLED(CONFIG_ARCH_HAS_UNCACHED_SEGMENT) &&
+ dma_alloc_need_uncached(dev, attrs))
+ cpu_addr = cached_kernel_address(cpu_addr);
__dma_direct_free_pages(dev, size, virt_to_page(cpu_addr));
}
void *dma_direct_alloc(struct device *dev, size_t size,
dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
{
- if (!dev_is_dma_coherent(dev))
+ if (!IS_ENABLED(CONFIG_ARCH_HAS_UNCACHED_SEGMENT) &&
+ 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);
}
@@ -203,7 +213,8 @@ void *dma_direct_alloc(struct device *dev, size_t size,
void dma_direct_free(struct device *dev, size_t size,
void *cpu_addr, dma_addr_t dma_addr, unsigned long attrs)
{
- if (!dev_is_dma_coherent(dev))
+ if (!IS_ENABLED(CONFIG_ARCH_HAS_UNCACHED_SEGMENT) &&
+ 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);
diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c
index f7afdadb6770..1f628e7ac709 100644
--- a/kernel/dma/mapping.c
+++ b/kernel/dma/mapping.c
@@ -317,6 +317,12 @@ void arch_dma_set_mask(struct device *dev, u64 mask);
int dma_set_mask(struct device *dev, u64 mask)
{
+ /*
+ * Truncate the mask to the actually supported dma_addr_t width to
+ * avoid generating unsupportable addresses.
+ */
+ mask = (dma_addr_t)mask;
+
if (!dev->dma_mask || !dma_supported(dev, mask))
return -EIO;
@@ -330,6 +336,12 @@ EXPORT_SYMBOL(dma_set_mask);
#ifndef CONFIG_ARCH_HAS_DMA_SET_COHERENT_MASK
int dma_set_coherent_mask(struct device *dev, u64 mask)
{
+ /*
+ * Truncate the mask to the actually supported dma_addr_t width to
+ * avoid generating unsupportable addresses.
+ */
+ mask = (dma_addr_t)mask;
+
if (!dma_supported(dev, mask))
return -EIO;
diff --git a/kernel/dma/remap.c b/kernel/dma/remap.c
index 7a723194ecbe..a594aec07882 100644
--- a/kernel/dma/remap.c
+++ b/kernel/dma/remap.c
@@ -158,6 +158,9 @@ out:
bool dma_in_atomic_pool(void *start, size_t size)
{
+ if (unlikely(!atomic_pool))
+ return false;
+
return addr_in_gen_pool(atomic_pool, (unsigned long)start, size);
}
@@ -199,8 +202,7 @@ void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
size = PAGE_ALIGN(size);
- if (!gfpflags_allow_blocking(flags) &&
- !(attrs & DMA_ATTR_NO_KERNEL_MAPPING)) {
+ if (!gfpflags_allow_blocking(flags)) {
ret = dma_alloc_from_pool(size, &page, flags);
if (!ret)
return NULL;
@@ -214,11 +216,6 @@ void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
/* remove any dirty cache lines on the kernel alias */
arch_dma_prep_coherent(page, size);
- if (attrs & DMA_ATTR_NO_KERNEL_MAPPING) {
- ret = page; /* opaque cookie */
- goto done;
- }
-
/* create a coherent mapping */
ret = dma_common_contiguous_remap(page, size, VM_USERMAP,
arch_dma_mmap_pgprot(dev, PAGE_KERNEL, attrs),
@@ -237,10 +234,7 @@ done:
void arch_dma_free(struct device *dev, size_t size, void *vaddr,
dma_addr_t dma_handle, unsigned long attrs)
{
- if (attrs & DMA_ATTR_NO_KERNEL_MAPPING) {
- /* vaddr is a struct page cookie, not a kernel address */
- __dma_direct_free_pages(dev, size, vaddr);
- } else if (!dma_free_from_pool(vaddr, PAGE_ALIGN(size))) {
+ if (!dma_free_from_pool(vaddr, PAGE_ALIGN(size))) {
phys_addr_t phys = dma_to_phys(dev, dma_handle);
struct page *page = pfn_to_page(__phys_to_pfn(phys));