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DMA-API: Change dma_declare_coherent_memory() CPU address to phys_addr_t

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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@google.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: James Bottomley <jbottomley@Parallels.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
This commit is contained in:
Bjorn Helgaas
2014-05-20 16:54:22 -06:00
parent 77f2ea2f8d
commit 88a984ba07
5 changed files with 21 additions and 24 deletions
Download Patch File Download Diff File Expand all files Collapse all files

6
drivers/base/dma-mapping.c
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@ -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);