[v2] fpga: dfl: afu: use PFN_DOWN() and PFN_PHYS() helper macros

[PATCH v2] fpga: dfl: afu: use PFN_DOWN() and PFN_PHYS() helper macros

Posted by Peter Colberg 2 years, 7 months ago

Replace all shifts by PAGE_SHIFT with PFN_DOWN() and PFN_PHYS() helper
macros to convert between physical addresses and 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>
---
v2:
- Comment in commit message that changes are cosmetic only
---
 drivers/fpga/dfl-afu-dma-region.c | 7 ++++---
 drivers/fpga/dfl-afu-main.c       | 5 +++--
 2 files changed, 7 insertions(+), 5 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++)
diff --git a/drivers/fpga/dfl-afu-main.c b/drivers/fpga/dfl-afu-main.c
index 7f621e96d3b8..048c9b418c8b 100644
--- a/drivers/fpga/dfl-afu-main.c
+++ b/drivers/fpga/dfl-afu-main.c
@@ -16,6 +16,7 @@
 
 #include <linux/kernel.h>
 #include <linux/module.h>
+#include <linux/pfn.h>
 #include <linux/uaccess.h>
 #include <linux/fpga-dfl.h>
 
@@ -816,7 +817,7 @@ static int afu_mmap(struct file *filp, struct vm_area_struct *vma)
 
 	pdata = dev_get_platdata(&pdev->dev);
 
-	offset = vma->vm_pgoff << PAGE_SHIFT;
+	offset = PFN_PHYS(vma->vm_pgoff);
 	ret = afu_mmio_region_get_by_offset(pdata, offset, size, &region);
 	if (ret)
 		return ret;
@@ -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);
 }
 
-- 
2.28.0

Re: [PATCH v2] fpga: dfl: afu: use PFN_DOWN() and PFN_PHYS() helper macros

Posted by Xu Yilun 2 years, 7 months ago

On 2023-06-19 at 15:56:34 -0400, Peter Colberg wrote:
> Replace all shifts by PAGE_SHIFT with PFN_DOWN() and PFN_PHYS() helper
> macros to convert between physical addresses and 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>
> ---
> v2:
> - Comment in commit message that changes are cosmetic only
> ---
>  drivers/fpga/dfl-afu-dma-region.c | 7 ++++---
>  drivers/fpga/dfl-afu-main.c       | 5 +++--
>  2 files changed, 7 insertions(+), 5 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);

I don't much prefer this change, it is not doing the phy addr to pfn
convertion. The macro name doesn't match what is doing here.

>  	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);

ditto

>  	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);

ditto

>  	int i;
>  
>  	for (i = 0; i < npages - 1; i++)
> diff --git a/drivers/fpga/dfl-afu-main.c b/drivers/fpga/dfl-afu-main.c
> index 7f621e96d3b8..048c9b418c8b 100644
> --- a/drivers/fpga/dfl-afu-main.c
> +++ b/drivers/fpga/dfl-afu-main.c
> @@ -16,6 +16,7 @@
>  
>  #include <linux/kernel.h>
>  #include <linux/module.h>
> +#include <linux/pfn.h>
>  #include <linux/uaccess.h>
>  #include <linux/fpga-dfl.h>
>  
> @@ -816,7 +817,7 @@ static int afu_mmap(struct file *filp, struct vm_area_struct *vma)
>  
>  	pdata = dev_get_platdata(&pdev->dev);
>  
> -	offset = vma->vm_pgoff << PAGE_SHIFT;
> +	offset = PFN_PHYS(vma->vm_pgoff);

ditto. The variables are offsets within file, not phys addr & pfn.

>  	ret = afu_mmio_region_get_by_offset(pdata, offset, size, &region);
>  	if (ret)
>  		return ret;
> @@ -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);
>  }
>  
> -- 
> 2.28.0
>

Re: [PATCH v2] fpga: dfl: afu: use PFN_DOWN() and PFN_PHYS() helper macros

Posted by Andy Shevchenko 2 years, 7 months ago

On Tue, Jun 27, 2023 at 02:26:27PM +0800, Xu Yilun wrote:
> On 2023-06-19 at 15:56:34 -0400, Peter Colberg wrote:

...

> > -	int npages = region->length >> PAGE_SHIFT;
> > +	int npages = PFN_DOWN(region->length);
> 
> I don't much prefer this change, it is not doing the phy addr to pfn
> convertion. The macro name doesn't match what is doing here.

This macro converts length to pages. And it's not about phy addr.

...

> > -	long npages = region->length >> PAGE_SHIFT;
> > +	long npages = PFN_DOWN(region->length);
> 
> ditto

Ditto.

...

> > -	int npages = region->length >> PAGE_SHIFT;
> > +	int npages = PFN_DOWN(region->length);
> 
> ditto

Ditto.

...

> > -	offset = vma->vm_pgoff << PAGE_SHIFT;
> > +	offset = PFN_PHYS(vma->vm_pgoff);
> 
> ditto. The variables are offsets within file, not phys addr & pfn.

Here I probably can agree.

-- 
With Best Regards,
Andy Shevchenko

Re: [PATCH v2] fpga: dfl: afu: use PFN_DOWN() and PFN_PHYS() helper macros

Posted by Xu Yilun 2 years, 7 months ago

On 2023-06-27 at 21:23:03 +0300, Andy Shevchenko wrote:
> On Tue, Jun 27, 2023 at 02:26:27PM +0800, Xu Yilun wrote:
> > On 2023-06-19 at 15:56:34 -0400, Peter Colberg wrote:
> 
> ...
> 
> > > -	int npages = region->length >> PAGE_SHIFT;
> > > +	int npages = PFN_DOWN(region->length);
> > 
> > I don't much prefer this change, it is not doing the phy addr to pfn
> > convertion. The macro name doesn't match what is doing here.
> 
> This macro converts length to pages. And it's not about phy addr.

You are right.

> > > -	offset = vma->vm_pgoff << PAGE_SHIFT;
> > > +	offset = PFN_PHYS(vma->vm_pgoff);
> > 
> > ditto. The variables are offsets within file, not phys addr & pfn.
> 
> Here I probably can agree.

OK. Remove this one, and others LGTM.

Thanks,
Yilun

> 
> -- 
> With Best Regards,
> Andy Shevchenko
> 
>

[PATCH v3] fpga: dfl: afu: use PFN_DOWN() helper macro

Posted by Peter Colberg 2 years, 7 months ago

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++)
-- 
2.28.0

Re: [PATCH v3] fpga: dfl: afu: use PFN_DOWN() helper macro

Posted by Xu Yilun 2 years, 7 months ago

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
>