diff --git a/arch/arm/Kconfig b/arch/arm/Kconfig
index c5f9ae5dbd1ad04da804d68e475d3b4b230832f6..2f88d8d9770116014f7ff55e80d98c65fbb191ed 100644
--- a/arch/arm/Kconfig
+++ b/arch/arm/Kconfig
@@ -6,7 +6,7 @@ config ARM
select HAVE_DMA_API_DEBUG
select HAVE_IDE if PCI || ISA || PCMCIA
select HAVE_DMA_ATTRS
- select HAVE_DMA_CONTIGUOUS if (CPU_V6 || CPU_V6K || CPU_V7)
+ select HAVE_DMA_CONTIGUOUS if MMU
select HAVE_MEMBLOCK
select RTC_LIB
select SYS_SUPPORTS_APM_EMULATION
diff --git a/arch/arm/include/asm/dma-mapping.h b/arch/arm/include/asm/dma-mapping.h
index 2ae842df455180d3bcd445d339ecd332d3b36c4e..5c44dcb0987bd31418298f7932baaa5a82320477 100644
--- a/arch/arm/include/asm/dma-mapping.h
+++ b/arch/arm/include/asm/dma-mapping.h
@@ -202,6 +202,13 @@ static inline void dma_free_writecombine(struct device *dev, size_t size,
return dma_free_attrs(dev, size, cpu_addr, dma_handle, &attrs);
}
+/*
+ * This can be called during early boot to increase the size of the atomic
+ * coherent DMA pool above the default value of 256KiB. It must be called
+ * before postcore_initcall.
+ */
+extern void __init init_dma_coherent_pool_size(unsigned long size);
+
/*
* This can be called during boot to increase the size of the consistent
* DMA region above it's default value of 2MB. It must be called before the
diff --git a/arch/arm/mach-kirkwood/common.c b/arch/arm/mach-kirkwood/common.c
index 3226077735b1d7104627f8f40307e84c97d4ca5b..1201191d7f1bb24c386df88f5fe4de14e172b006 100644
--- a/arch/arm/mach-kirkwood/common.c
+++ b/arch/arm/mach-kirkwood/common.c
@@ -517,6 +517,13 @@ void __init kirkwood_wdt_init(void)
void __init kirkwood_init_early(void)
{
orion_time_set_base(TIMER_VIRT_BASE);
+
+ /*
+ * Some Kirkwood devices allocate their coherent buffers from atomic
+ * context. Increase size of atomic coherent pool to make sure such
+ * the allocations won't fail.
+ */
+ init_dma_coherent_pool_size(SZ_1M);
}
int kirkwood_tclk;
diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index 4e7d1182e8a3a59270073b5cb3b348e0bd690ef8..051204fc4617670321bfa5fa7c1f3621cb49a33c 100644
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c
@@ -267,17 +267,19 @@ static void __dma_free_remap(void *cpu_addr, size_t size)
vunmap(cpu_addr);
}
+#define DEFAULT_DMA_COHERENT_POOL_SIZE SZ_256K
+
struct dma_pool {
size_t size;
spinlock_t lock;
unsigned long *bitmap;
unsigned long nr_pages;
void *vaddr;
- struct page *page;
+ struct page **pages;
};
static struct dma_pool atomic_pool = {
- .size = SZ_256K,
+ .size = DEFAULT_DMA_COHERENT_POOL_SIZE,
};
static int __init early_coherent_pool(char *p)
@@ -287,6 +289,21 @@ static int __init early_coherent_pool(char *p)
}
early_param("coherent_pool", early_coherent_pool);
+void __init init_dma_coherent_pool_size(unsigned long size)
+{
+ /*
+ * Catch any attempt to set the pool size too late.
+ */
+ BUG_ON(atomic_pool.vaddr);
+
+ /*
+ * Set architecture specific coherent pool size only if
+ * it has not been changed by kernel command line parameter.
+ */
+ if (atomic_pool.size == DEFAULT_DMA_COHERENT_POOL_SIZE)
+ atomic_pool.size = size;
+}
+
/*
* Initialise the coherent pool for atomic allocations.
*/
@@ -297,6 +314,7 @@ static int __init atomic_pool_init(void)
unsigned long nr_pages = pool->size >> PAGE_SHIFT;
unsigned long *bitmap;
struct page *page;
+ struct page **pages;
void *ptr;
int bitmap_size = BITS_TO_LONGS(nr_pages) * sizeof(long);
@@ -304,21 +322,31 @@ static int __init atomic_pool_init(void)
if (!bitmap)
goto no_bitmap;
+ pages = kzalloc(nr_pages * sizeof(struct page *), GFP_KERNEL);
+ if (!pages)
+ goto no_pages;
+
if (IS_ENABLED(CONFIG_CMA))
ptr = __alloc_from_contiguous(NULL, pool->size, prot, &page);
else
ptr = __alloc_remap_buffer(NULL, pool->size, GFP_KERNEL, prot,
&page, NULL);
if (ptr) {
+ int i;
+
+ for (i = 0; i < nr_pages; i++)
+ pages[i] = page + i;
+
spin_lock_init(&pool->lock);
pool->vaddr = ptr;
- pool->page = page;
+ pool->pages = pages;
pool->bitmap = bitmap;
pool->nr_pages = nr_pages;
pr_info("DMA: preallocated %u KiB pool for atomic coherent allocations\n",
(unsigned)pool->size / 1024);
return 0;
}
+no_pages:
kfree(bitmap);
no_bitmap:
pr_err("DMA: failed to allocate %u KiB pool for atomic coherent allocation\n",
@@ -443,27 +471,45 @@ static void *__alloc_from_pool(size_t size, struct page **ret_page)
if (pageno < pool->nr_pages) {
bitmap_set(pool->bitmap, pageno, count);
ptr = pool->vaddr + PAGE_SIZE * pageno;
- *ret_page = pool->page + pageno;
+ *ret_page = pool->pages[pageno];
+ } else {
+ pr_err_once("ERROR: %u KiB atomic DMA coherent pool is too small!\n"
+ "Please increase it with coherent_pool= kernel parameter!\n",
+ (unsigned)pool->size / 1024);
}
spin_unlock_irqrestore(&pool->lock, flags);
return ptr;
}
+static bool __in_atomic_pool(void *start, size_t size)
+{
+ struct dma_pool *pool = &atomic_pool;
+ void *end = start + size;
+ void *pool_start = pool->vaddr;
+ void *pool_end = pool->vaddr + pool->size;
+
+ if (start < pool_start || start > pool_end)
+ return false;
+
+ if (end <= pool_end)
+ return true;
+
+ WARN(1, "Wrong coherent size(%p-%p) from atomic pool(%p-%p)\n",
+ start, end - 1, pool_start, pool_end - 1);
+
+ return false;
+}
+
static int __free_from_pool(void *start, size_t size)
{
struct dma_pool *pool = &atomic_pool;
unsigned long pageno, count;
unsigned long flags;
- if (start < pool->vaddr || start > pool->vaddr + pool->size)
+ if (!__in_atomic_pool(start, size))
return 0;
- if (start + size > pool->vaddr + pool->size) {
- WARN(1, "freeing wrong coherent size from pool\n");
- return 0;
- }
-
pageno = (start - pool->vaddr) >> PAGE_SHIFT;
count = size >> PAGE_SHIFT;
@@ -1090,10 +1136,22 @@ static int __iommu_remove_mapping(struct device *dev, dma_addr_t iova, size_t si
return 0;
}
+static struct page **__atomic_get_pages(void *addr)
+{
+ struct dma_pool *pool = &atomic_pool;
+ struct page **pages = pool->pages;
+ int offs = (addr - pool->vaddr) >> PAGE_SHIFT;
+
+ return pages + offs;
+}
+
static struct page **__iommu_get_pages(void *cpu_addr, struct dma_attrs *attrs)
{
struct vm_struct *area;
+ if (__in_atomic_pool(cpu_addr, PAGE_SIZE))
+ return __atomic_get_pages(cpu_addr);
+
if (dma_get_attr(DMA_ATTR_NO_KERNEL_MAPPING, attrs))
return cpu_addr;
@@ -1103,6 +1161,34 @@ static struct page **__iommu_get_pages(void *cpu_addr, struct dma_attrs *attrs)
return NULL;
}
+static void *__iommu_alloc_atomic(struct device *dev, size_t size,
+ dma_addr_t *handle)
+{
+ struct page *page;
+ void *addr;
+
+ addr = __alloc_from_pool(size, &page);
+ if (!addr)
+ return NULL;
+
+ *handle = __iommu_create_mapping(dev, &page, size);
+ if (*handle == DMA_ERROR_CODE)
+ goto err_mapping;
+
+ return addr;
+
+err_mapping:
+ __free_from_pool(addr, size);
+ return NULL;
+}
+
+static void __iommu_free_atomic(struct device *dev, struct page **pages,
+ dma_addr_t handle, size_t size)
+{
+ __iommu_remove_mapping(dev, handle, size);
+ __free_from_pool(page_address(pages[0]), size);
+}
+
static void *arm_iommu_alloc_attrs(struct device *dev, size_t size,
dma_addr_t *handle, gfp_t gfp, struct dma_attrs *attrs)
{
@@ -1113,6 +1199,9 @@ static void *arm_iommu_alloc_attrs(struct device *dev, size_t size,
*handle = DMA_ERROR_CODE;
size = PAGE_ALIGN(size);
+ if (gfp & GFP_ATOMIC)
+ return __iommu_alloc_atomic(dev, size, handle);
+
pages = __iommu_alloc_buffer(dev, size, gfp);
if (!pages)
return NULL;
@@ -1179,6 +1268,11 @@ void arm_iommu_free_attrs(struct device *dev, size_t size, void *cpu_addr,
return;
}
+ if (__in_atomic_pool(cpu_addr, size)) {
+ __iommu_free_atomic(dev, pages, handle, size);
+ return;
+ }
+
if (!dma_get_attr(DMA_ATTR_NO_KERNEL_MAPPING, attrs)) {
unmap_kernel_range((unsigned long)cpu_addr, size);
vunmap(cpu_addr);
diff --git a/drivers/base/dma-contiguous.c b/drivers/base/dma-contiguous.c
index 78efb0306a446027f7fce1019572902f5aaa805b..34d94c762a1e79415fc00b0fc59caf034a3e186a 100644
--- a/drivers/base/dma-contiguous.c
+++ b/drivers/base/dma-contiguous.c
@@ -250,7 +250,7 @@ int __init dma_declare_contiguous(struct device *dev, unsigned long size,
return -EINVAL;
/* Sanitise input arguments */
- alignment = PAGE_SIZE << max(MAX_ORDER, pageblock_order);
+ alignment = PAGE_SIZE << max(MAX_ORDER - 1, pageblock_order);
base = ALIGN(base, alignment);
size = ALIGN(size, alignment);
limit &= ~(alignment - 1);