aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/base/dma-coherent.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/base/dma-coherent.c')
-rw-r--r--drivers/base/dma-coherent.c246
1 files changed, 142 insertions, 104 deletions
diff --git a/drivers/base/dma-coherent.c b/drivers/base/dma-coherent.c
index 2ae24c28e70c..744f64f43454 100644
--- a/drivers/base/dma-coherent.c
+++ b/drivers/base/dma-coherent.c
@@ -25,7 +25,7 @@ static inline struct dma_coherent_mem *dev_get_coherent_memory(struct device *de
{
if (dev && dev->dma_mem)
return dev->dma_mem;
- return dma_coherent_default_memory;
+ return NULL;
}
static inline dma_addr_t dma_get_device_base(struct device *dev,
@@ -37,7 +37,7 @@ static inline dma_addr_t dma_get_device_base(struct device *dev,
return mem->device_base;
}
-static bool dma_init_coherent_memory(
+static int dma_init_coherent_memory(
phys_addr_t phys_addr, dma_addr_t device_addr, size_t size, int flags,
struct dma_coherent_mem **mem)
{
@@ -45,25 +45,28 @@ static bool dma_init_coherent_memory(
void __iomem *mem_base = NULL;
int pages = size >> PAGE_SHIFT;
int bitmap_size = BITS_TO_LONGS(pages) * sizeof(long);
+ int ret;
- if ((flags & (DMA_MEMORY_MAP | DMA_MEMORY_IO)) == 0)
- goto out;
- if (!size)
+ if (!size) {
+ ret = -EINVAL;
goto out;
+ }
- if (flags & DMA_MEMORY_MAP)
- mem_base = memremap(phys_addr, size, MEMREMAP_WC);
- else
- mem_base = ioremap(phys_addr, size);
- if (!mem_base)
+ mem_base = memremap(phys_addr, size, MEMREMAP_WC);
+ if (!mem_base) {
+ ret = -EINVAL;
goto out;
-
+ }
dma_mem = kzalloc(sizeof(struct dma_coherent_mem), GFP_KERNEL);
- if (!dma_mem)
+ if (!dma_mem) {
+ ret = -ENOMEM;
goto out;
+ }
dma_mem->bitmap = kzalloc(bitmap_size, GFP_KERNEL);
- if (!dma_mem->bitmap)
+ if (!dma_mem->bitmap) {
+ ret = -ENOMEM;
goto out;
+ }
dma_mem->virt_base = mem_base;
dma_mem->device_base = device_addr;
@@ -73,17 +76,13 @@ static bool dma_init_coherent_memory(
spin_lock_init(&dma_mem->spinlock);
*mem = dma_mem;
- return true;
+ return 0;
out:
kfree(dma_mem);
- if (mem_base) {
- if (flags & DMA_MEMORY_MAP)
- memunmap(mem_base);
- else
- iounmap(mem_base);
- }
- return false;
+ if (mem_base)
+ memunmap(mem_base);
+ return ret;
}
static void dma_release_coherent_memory(struct dma_coherent_mem *mem)
@@ -91,10 +90,7 @@ static void dma_release_coherent_memory(struct dma_coherent_mem *mem)
if (!mem)
return;
- if (mem->flags & DMA_MEMORY_MAP)
- memunmap(mem->virt_base);
- else
- iounmap(mem->virt_base);
+ memunmap(mem->virt_base);
kfree(mem->bitmap);
kfree(mem);
}
@@ -109,8 +105,6 @@ static int dma_assign_coherent_memory(struct device *dev,
return -EBUSY;
dev->dma_mem = mem;
- /* FIXME: this routine just ignores DMA_MEMORY_INCLUDES_CHILDREN */
-
return 0;
}
@@ -118,16 +112,16 @@ int dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr,
dma_addr_t device_addr, size_t size, int flags)
{
struct dma_coherent_mem *mem;
+ int ret;
- if (!dma_init_coherent_memory(phys_addr, device_addr, size, flags,
- &mem))
- return 0;
-
- if (dma_assign_coherent_memory(dev, mem) == 0)
- return flags & DMA_MEMORY_MAP ? DMA_MEMORY_MAP : DMA_MEMORY_IO;
+ ret = dma_init_coherent_memory(phys_addr, device_addr, size, flags, &mem);
+ if (ret)
+ return ret;
- dma_release_coherent_memory(mem);
- return 0;
+ ret = dma_assign_coherent_memory(dev, mem);
+ if (ret)
+ dma_release_coherent_memory(mem);
+ return ret;
}
EXPORT_SYMBOL(dma_declare_coherent_memory);
@@ -165,9 +159,38 @@ void *dma_mark_declared_memory_occupied(struct device *dev,
}
EXPORT_SYMBOL(dma_mark_declared_memory_occupied);
+static void *__dma_alloc_from_coherent(struct dma_coherent_mem *mem,
+ ssize_t size, dma_addr_t *dma_handle)
+{
+ int order = get_order(size);
+ unsigned long flags;
+ int pageno;
+ void *ret;
+
+ spin_lock_irqsave(&mem->spinlock, flags);
+
+ if (unlikely(size > (mem->size << PAGE_SHIFT)))
+ goto err;
+
+ pageno = bitmap_find_free_region(mem->bitmap, mem->size, order);
+ if (unlikely(pageno < 0))
+ goto err;
+
+ /*
+ * Memory was found in the coherent area.
+ */
+ *dma_handle = mem->device_base + (pageno << PAGE_SHIFT);
+ ret = mem->virt_base + (pageno << PAGE_SHIFT);
+ spin_unlock_irqrestore(&mem->spinlock, flags);
+ memset(ret, 0, size);
+ return ret;
+err:
+ spin_unlock_irqrestore(&mem->spinlock, flags);
+ return NULL;
+}
+
/**
- * dma_alloc_from_coherent() - try to allocate memory from the per-device coherent area
- *
+ * dma_alloc_from_dev_coherent() - allocate memory from device coherent pool
* @dev: device from which we allocate memory
* @size: size of requested memory area
* @dma_handle: This will be filled with the correct dma handle
@@ -180,44 +203,18 @@ EXPORT_SYMBOL(dma_mark_declared_memory_occupied);
* Returns 0 if dma_alloc_coherent should continue with allocating from
* generic memory areas, or !0 if dma_alloc_coherent should return @ret.
*/
-int dma_alloc_from_coherent(struct device *dev, ssize_t size,
- dma_addr_t *dma_handle, void **ret)
+int dma_alloc_from_dev_coherent(struct device *dev, ssize_t size,
+ dma_addr_t *dma_handle, void **ret)
{
struct dma_coherent_mem *mem = dev_get_coherent_memory(dev);
- int order = get_order(size);
- unsigned long flags;
- int pageno;
- int dma_memory_map;
if (!mem)
return 0;
- *ret = NULL;
- spin_lock_irqsave(&mem->spinlock, flags);
-
- if (unlikely(size > (mem->size << PAGE_SHIFT)))
- goto err;
-
- pageno = bitmap_find_free_region(mem->bitmap, mem->size, order);
- if (unlikely(pageno < 0))
- goto err;
-
- /*
- * Memory was found in the per-device area.
- */
- *dma_handle = dma_get_device_base(dev, mem) + (pageno << PAGE_SHIFT);
- *ret = mem->virt_base + (pageno << PAGE_SHIFT);
- dma_memory_map = (mem->flags & DMA_MEMORY_MAP);
- spin_unlock_irqrestore(&mem->spinlock, flags);
- if (dma_memory_map)
- memset(*ret, 0, size);
- else
- memset_io(*ret, 0, size);
-
- return 1;
+ *ret = __dma_alloc_from_coherent(mem, size, dma_handle);
+ if (*ret)
+ return 1;
-err:
- spin_unlock_irqrestore(&mem->spinlock, flags);
/*
* In the case where the allocation can not be satisfied from the
* per-device area, try to fall back to generic memory if the
@@ -225,25 +222,20 @@ err:
*/
return mem->flags & DMA_MEMORY_EXCLUSIVE;
}
-EXPORT_SYMBOL(dma_alloc_from_coherent);
+EXPORT_SYMBOL(dma_alloc_from_dev_coherent);
-/**
- * dma_release_from_coherent() - try to free the memory allocated from per-device coherent memory pool
- * @dev: device from which the memory was allocated
- * @order: the order of pages allocated
- * @vaddr: virtual address of allocated pages
- *
- * This checks whether the memory was allocated from the per-device
- * coherent memory pool and if so, releases that memory.
- *
- * Returns 1 if we correctly released the memory, or 0 if
- * dma_release_coherent() should proceed with releasing memory from
- * generic pools.
- */
-int dma_release_from_coherent(struct device *dev, int order, void *vaddr)
+void *dma_alloc_from_global_coherent(ssize_t size, dma_addr_t *dma_handle)
{
- struct dma_coherent_mem *mem = dev_get_coherent_memory(dev);
+ if (!dma_coherent_default_memory)
+ return NULL;
+
+ return __dma_alloc_from_coherent(dma_coherent_default_memory, size,
+ dma_handle);
+}
+static int __dma_release_from_coherent(struct dma_coherent_mem *mem,
+ int order, void *vaddr)
+{
if (mem && vaddr >= mem->virt_base && vaddr <
(mem->virt_base + (mem->size << PAGE_SHIFT))) {
int page = (vaddr - mem->virt_base) >> PAGE_SHIFT;
@@ -256,28 +248,39 @@ int dma_release_from_coherent(struct device *dev, int order, void *vaddr)
}
return 0;
}
-EXPORT_SYMBOL(dma_release_from_coherent);
/**
- * dma_mmap_from_coherent() - try to mmap the memory allocated from
- * per-device coherent memory pool to userspace
+ * dma_release_from_dev_coherent() - free memory to device coherent memory pool
* @dev: device from which the memory was allocated
- * @vma: vm_area for the userspace memory
- * @vaddr: cpu address returned by dma_alloc_from_coherent
- * @size: size of the memory buffer allocated by dma_alloc_from_coherent
- * @ret: result from remap_pfn_range()
+ * @order: the order of pages allocated
+ * @vaddr: virtual address of allocated pages
*
* This checks whether the memory was allocated from the per-device
- * coherent memory pool and if so, maps that memory to the provided vma.
+ * coherent memory pool and if so, releases that memory.
*
- * Returns 1 if we correctly mapped the memory, or 0 if the caller should
- * proceed with mapping memory from generic pools.
+ * Returns 1 if we correctly released the memory, or 0 if the caller should
+ * proceed with releasing memory from generic pools.
*/
-int dma_mmap_from_coherent(struct device *dev, struct vm_area_struct *vma,
- void *vaddr, size_t size, int *ret)
+int dma_release_from_dev_coherent(struct device *dev, int order, void *vaddr)
{
struct dma_coherent_mem *mem = dev_get_coherent_memory(dev);
+ return __dma_release_from_coherent(mem, order, vaddr);
+}
+EXPORT_SYMBOL(dma_release_from_dev_coherent);
+
+int dma_release_from_global_coherent(int order, void *vaddr)
+{
+ if (!dma_coherent_default_memory)
+ return 0;
+
+ return __dma_release_from_coherent(dma_coherent_default_memory, order,
+ vaddr);
+}
+
+static int __dma_mmap_from_coherent(struct dma_coherent_mem *mem,
+ struct vm_area_struct *vma, void *vaddr, size_t size, int *ret)
+{
if (mem && vaddr >= mem->virt_base && vaddr + size <=
(mem->virt_base + (mem->size << PAGE_SHIFT))) {
unsigned long off = vma->vm_pgoff;
@@ -296,7 +299,39 @@ int dma_mmap_from_coherent(struct device *dev, struct vm_area_struct *vma,
}
return 0;
}
-EXPORT_SYMBOL(dma_mmap_from_coherent);
+
+/**
+ * dma_mmap_from_dev_coherent() - mmap memory from the device coherent pool
+ * @dev: device from which the memory was allocated
+ * @vma: vm_area for the userspace memory
+ * @vaddr: cpu address returned by dma_alloc_from_dev_coherent
+ * @size: size of the memory buffer allocated
+ * @ret: result from remap_pfn_range()
+ *
+ * This checks whether the memory was allocated from the per-device
+ * coherent memory pool and if so, maps that memory to the provided vma.
+ *
+ * Returns 1 if we correctly mapped the memory, or 0 if the caller should
+ * proceed with mapping memory from generic pools.
+ */
+int dma_mmap_from_dev_coherent(struct device *dev, struct vm_area_struct *vma,
+ void *vaddr, size_t size, int *ret)
+{
+ struct dma_coherent_mem *mem = dev_get_coherent_memory(dev);
+
+ return __dma_mmap_from_coherent(mem, vma, vaddr, size, ret);
+}
+EXPORT_SYMBOL(dma_mmap_from_dev_coherent);
+
+int dma_mmap_from_global_coherent(struct vm_area_struct *vma, void *vaddr,
+ size_t size, int *ret)
+{
+ if (!dma_coherent_default_memory)
+ return 0;
+
+ return __dma_mmap_from_coherent(dma_coherent_default_memory, vma,
+ vaddr, size, ret);
+}
/*
* Support for reserved memory regions defined in device tree
@@ -311,14 +346,17 @@ static struct reserved_mem *dma_reserved_default_memory __initdata;
static int rmem_dma_device_init(struct reserved_mem *rmem, struct device *dev)
{
struct dma_coherent_mem *mem = rmem->priv;
+ int ret;
- if (!mem &&
- !dma_init_coherent_memory(rmem->base, rmem->base, rmem->size,
- DMA_MEMORY_MAP | DMA_MEMORY_EXCLUSIVE,
- &mem)) {
- pr_err("Reserved memory: failed to init DMA memory pool at %pa, size %ld MiB\n",
- &rmem->base, (unsigned long)rmem->size / SZ_1M);
- return -ENODEV;
+ if (!mem) {
+ ret = dma_init_coherent_memory(rmem->base, rmem->base,
+ rmem->size,
+ DMA_MEMORY_EXCLUSIVE, &mem);
+ if (ret) {
+ pr_err("Reserved memory: failed to init DMA memory pool at %pa, size %ld MiB\n",
+ &rmem->base, (unsigned long)rmem->size / SZ_1M);
+ return ret;
+ }
}
mem->use_dev_dma_pfn_offset = true;
rmem->priv = mem;