[PATCH v3 2/4] DMA-API: Change dma_declare_coherent_memory() CPU address to phys_addr_t
From: Bjorn Helgaas
Date: Thu May 08 2014 - 16:49:07 EST
dma_declare_coherent_memory() takes two addresses for a region of memory: a
"bus_addr" and a "device_addr". I think the intent is that "bus_addr" is
the physical address a *CPU* would use to access the region, and
"device_addr" is the bus address the *device* would use to address the
region.
Rename "bus_addr" to "phys_addr" and change its type to phys_addr_t.
Most callers already supply a phys_addr_t for this argument. The others
supply a 32-bit integer (a constant, unsigned int, or __u32) and need no
change.
Use "unsigned long", not phys_addr_t, to hold PFNs.
No functional change (this could theoretically fix a truncation in a config
with 32-bit dma_addr_t and 64-bit phys_addr_t, but I don't think there are
any such cases involving this code).
Signed-off-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
Acked-by: Arnd Bergmann <arnd@xxxxxxxx>
---
Documentation/DMA-API.txt | 9 ++++-----
drivers/base/dma-coherent.c | 10 +++++-----
drivers/base/dma-mapping.c | 6 +++---
include/asm-generic/dma-coherent.h | 13 +++++--------
include/linux/dma-mapping.h | 7 ++++---
5 files changed, 21 insertions(+), 24 deletions(-)
diff --git a/Documentation/DMA-API.txt b/Documentation/DMA-API.txt
index 1147eba43128..4f1cdc5febd1 100644
--- a/Documentation/DMA-API.txt
+++ b/Documentation/DMA-API.txt
@@ -497,19 +497,18 @@ continuing on for size. Again, you *must* observe the cache line
boundaries when doing this.
int
-dma_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
+dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr,
dma_addr_t device_addr, size_t size, int
flags)
Declare region of memory to be handed out by dma_alloc_coherent() when
it's asked for coherent memory for this device.
-bus_addr is the physical address to which the memory is currently
-assigned in the bus responding region (this will be used by the
-platform to perform the mapping).
+phys_addr is the cpu physical address to which the memory is currently
+assigned (this will be ioremapped so the cpu can access the region).
device_addr is the bus address the device needs to be programmed
-with actually to address this memory (this will be handed out as the
+with to actually address this memory (this will be handed out as the
dma_addr_t in dma_alloc_coherent()).
size is the size of the area (must be multiples of PAGE_SIZE).
diff --git a/drivers/base/dma-coherent.c b/drivers/base/dma-coherent.c
index bc256b641027..7d6e84a51424 100644
--- a/drivers/base/dma-coherent.c
+++ b/drivers/base/dma-coherent.c
@@ -10,13 +10,13 @@
struct dma_coherent_mem {
void *virt_base;
dma_addr_t device_base;
- phys_addr_t pfn_base;
+ unsigned long pfn_base;
int size;
int flags;
unsigned long *bitmap;
};
-int dma_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
+int dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr,
dma_addr_t device_addr, size_t size, int flags)
{
void __iomem *mem_base = NULL;
@@ -32,7 +32,7 @@ int dma_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
/* FIXME: this routine just ignores DMA_MEMORY_INCLUDES_CHILDREN */
- mem_base = ioremap(bus_addr, size);
+ mem_base = ioremap(phys_addr, size);
if (!mem_base)
goto out;
@@ -45,7 +45,7 @@ int dma_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
dev->dma_mem->virt_base = mem_base;
dev->dma_mem->device_base = device_addr;
- dev->dma_mem->pfn_base = PFN_DOWN(bus_addr);
+ dev->dma_mem->pfn_base = PFN_DOWN(phys_addr);
dev->dma_mem->size = pages;
dev->dma_mem->flags = flags;
@@ -208,7 +208,7 @@ int dma_mmap_from_coherent(struct device *dev, struct vm_area_struct *vma,
*ret = -ENXIO;
if (off < count && user_count <= count - off) {
- unsigned pfn = mem->pfn_base + start + off;
+ unsigned long pfn = mem->pfn_base + start + off;
*ret = remap_pfn_range(vma, vma->vm_start, pfn,
user_count << PAGE_SHIFT,
vma->vm_page_prot);
diff --git a/drivers/base/dma-mapping.c b/drivers/base/dma-mapping.c
index 0ce39a33b3c2..6cd08e145bfa 100644
--- a/drivers/base/dma-mapping.c
+++ b/drivers/base/dma-mapping.c
@@ -175,7 +175,7 @@ static void dmam_coherent_decl_release(struct device *dev, void *res)
/**
* dmam_declare_coherent_memory - Managed dma_declare_coherent_memory()
* @dev: Device to declare coherent memory for
- * @bus_addr: Bus address of coherent memory to be declared
+ * @phys_addr: Physical address of coherent memory to be declared
* @device_addr: Device address of coherent memory to be declared
* @size: Size of coherent memory to be declared
* @flags: Flags
@@ -185,7 +185,7 @@ static void dmam_coherent_decl_release(struct device *dev, void *res)
* RETURNS:
* 0 on success, -errno on failure.
*/
-int dmam_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
+int dmam_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr,
dma_addr_t device_addr, size_t size, int flags)
{
void *res;
@@ -195,7 +195,7 @@ int dmam_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
if (!res)
return -ENOMEM;
- rc = dma_declare_coherent_memory(dev, bus_addr, device_addr, size,
+ rc = dma_declare_coherent_memory(dev, phys_addr, device_addr, size,
flags);
if (rc == 0)
devres_add(dev, res);
diff --git a/include/asm-generic/dma-coherent.h b/include/asm-generic/dma-coherent.h
index 2be8a2dbc868..0297e5875798 100644
--- a/include/asm-generic/dma-coherent.h
+++ b/include/asm-generic/dma-coherent.h
@@ -16,16 +16,13 @@ int dma_mmap_from_coherent(struct device *dev, struct vm_area_struct *vma,
* Standard interface
*/
#define ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY
-extern int
-dma_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
- dma_addr_t device_addr, size_t size, int flags);
+int dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr,
+ dma_addr_t device_addr, size_t size, int flags);
-extern void
-dma_release_declared_memory(struct device *dev);
+void dma_release_declared_memory(struct device *dev);
-extern void *
-dma_mark_declared_memory_occupied(struct device *dev,
- dma_addr_t device_addr, size_t size);
+void *dma_mark_declared_memory_occupied(struct device *dev,
+ dma_addr_t device_addr, size_t size);
#else
#define dma_alloc_from_coherent(dev, size, handle, ret) (0)
#define dma_release_from_coherent(dev, order, vaddr) (0)
diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index b9aa2b97aab5..0c3eab1e39ac 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h
@@ -192,7 +192,7 @@ static inline int dma_get_cache_alignment(void)
#ifndef ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY
static inline int
-dma_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
+dma_declare_coherent_memory(struct device *dev, phys_addr_t phys_addr,
dma_addr_t device_addr, size_t size, int flags)
{
return 0;
@@ -223,13 +223,14 @@ extern void *dmam_alloc_noncoherent(struct device *dev, size_t size,
extern void dmam_free_noncoherent(struct device *dev, size_t size, void *vaddr,
dma_addr_t dma_handle);
#ifdef ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY
-extern int dmam_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
+extern int dmam_declare_coherent_memory(struct device *dev,
+ phys_addr_t phys_addr,
dma_addr_t device_addr, size_t size,
int flags);
extern void dmam_release_declared_memory(struct device *dev);
#else /* ARCH_HAS_DMA_DECLARE_COHERENT_MEMORY */
static inline int dmam_declare_coherent_memory(struct device *dev,
- dma_addr_t bus_addr, dma_addr_t device_addr,
+ phys_addr_t phys_addr, dma_addr_t device_addr,
size_t size, gfp_t gfp)
{
return 0;
--
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