[v3] fpga: dfl: afu: use PFN_DOWN() helper macro
Commit Message
Replace right shifts by PAGE_SHIFT with PFN_DOWN() helper macro to convert
from physical addresses to page frame numbers.
These changes are cosmetic only; no functional changes.
Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Peter Colberg <peter.colberg@intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
---
v3:
- Revert afu_mmap(), which calculates file offsets, not physical pages
v2:
- Comment in commit message that changes are cosmetic only
---
drivers/fpga/dfl-afu-dma-region.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
Comments
On 2023-06-28 at 20:22:55 -0400, Peter Colberg wrote:
> Replace right shifts by PAGE_SHIFT with PFN_DOWN() helper macro to convert
> from physical addresses to page frame numbers.
>
> These changes are cosmetic only; no functional changes.
>
> Suggested-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> Signed-off-by: Peter Colberg <peter.colberg@intel.com>
> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
> ---
> v3:
> - Revert afu_mmap(), which calculates file offsets, not physical pages
> v2:
> - Comment in commit message that changes are cosmetic only
> ---
> drivers/fpga/dfl-afu-dma-region.c | 7 ++++---
> 1 file changed, 4 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/fpga/dfl-afu-dma-region.c b/drivers/fpga/dfl-afu-dma-region.c
> index 02b60fde0430..e8d54cfbb301 100644
> --- a/drivers/fpga/dfl-afu-dma-region.c
> +++ b/drivers/fpga/dfl-afu-dma-region.c
> @@ -10,6 +10,7 @@
> */
>
> #include <linux/dma-mapping.h>
> +#include <linux/pfn.h>
> #include <linux/sched/signal.h>
> #include <linux/uaccess.h>
> #include <linux/mm.h>
> @@ -34,7 +35,7 @@ void afu_dma_region_init(struct dfl_feature_platform_data *pdata)
> static int afu_dma_pin_pages(struct dfl_feature_platform_data *pdata,
> struct dfl_afu_dma_region *region)
> {
> - int npages = region->length >> PAGE_SHIFT;
> + int npages = PFN_DOWN(region->length);
> struct device *dev = &pdata->dev->dev;
> int ret, pinned;
>
> @@ -82,7 +83,7 @@ static int afu_dma_pin_pages(struct dfl_feature_platform_data *pdata,
> static void afu_dma_unpin_pages(struct dfl_feature_platform_data *pdata,
> struct dfl_afu_dma_region *region)
> {
> - long npages = region->length >> PAGE_SHIFT;
> + long npages = PFN_DOWN(region->length);
> struct device *dev = &pdata->dev->dev;
>
> unpin_user_pages(region->pages, npages);
> @@ -101,7 +102,7 @@ static void afu_dma_unpin_pages(struct dfl_feature_platform_data *pdata,
> */
> static bool afu_dma_check_continuous_pages(struct dfl_afu_dma_region *region)
> {
> - int npages = region->length >> PAGE_SHIFT;
> + int npages = PFN_DOWN(region->length);
> int i;
>
> for (i = 0; i < npages - 1; i++)
@@ -837,7 +838,7 @@ static int afu_mmap(struct file *filp, struct vm_area_struct *vma)
vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
return remap_pfn_range(vma, vma->vm_start,
- (region.phys + (offset - region.offset)) >> PAGE_SHIFT,
+ PFN_DOWN(region.phys + (offset - region.offset)),
size, vma->vm_page_prot);
Why is this change also dropped? Maybe use PHYS_PFN() instead?
Thanks,
Yilun
> --
> 2.28.0
>
@@ -10,6 +10,7 @@
*/
#include <linux/dma-mapping.h>
+#include <linux/pfn.h>
#include <linux/sched/signal.h>
#include <linux/uaccess.h>
#include <linux/mm.h>
@@ -34,7 +35,7 @@ void afu_dma_region_init(struct dfl_feature_platform_data *pdata)
static int afu_dma_pin_pages(struct dfl_feature_platform_data *pdata,
struct dfl_afu_dma_region *region)
{
- int npages = region->length >> PAGE_SHIFT;
+ int npages = PFN_DOWN(region->length);
struct device *dev = &pdata->dev->dev;
int ret, pinned;
@@ -82,7 +83,7 @@ static int afu_dma_pin_pages(struct dfl_feature_platform_data *pdata,
static void afu_dma_unpin_pages(struct dfl_feature_platform_data *pdata,
struct dfl_afu_dma_region *region)
{
- long npages = region->length >> PAGE_SHIFT;
+ long npages = PFN_DOWN(region->length);
struct device *dev = &pdata->dev->dev;
unpin_user_pages(region->pages, npages);
@@ -101,7 +102,7 @@ static void afu_dma_unpin_pages(struct dfl_feature_platform_data *pdata,
*/
static bool afu_dma_check_continuous_pages(struct dfl_afu_dma_region *region)
{
- int npages = region->length >> PAGE_SHIFT;
+ int npages = PFN_DOWN(region->length);
int i;
for (i = 0; i < npages - 1; i++)