[v2,20/35] platform/x86/asus: Use kmemdup rather than duplicating its implementation
diff mbox series

Message ID 20190703162951.32737-1-huangfq.daxian@gmail.com
State Accepted, archived
Delegated to: Andy Shevchenko
Headers show
Series
  • Untitled series #141727
Related show

Commit Message

Fuqian Huang July 3, 2019, 4:29 p.m. UTC
kmemdup is introduced to duplicate a region of memory in a neat way.
Rather than kmalloc/kzalloc + memcpy, which the programmer needs to
write the size twice (sometimes lead to mistakes), kmemdup improves
readability, leads to smaller code and also reduce the chances of mistakes.
Suggestion to use kmemdup rather than using kmalloc/kzalloc + memcpy.

Signed-off-by: Fuqian Huang <huangfq.daxian@gmail.com>
---
Changes in v2:
  - Fix a typo in commit message (memset -> memcpy)
  - Split into two patches.

 drivers/platform/x86/asus-wmi.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

Comments

Andy Shevchenko July 25, 2019, 5:43 p.m. UTC | #1
On Wed, Jul 3, 2019 at 7:30 PM Fuqian Huang <huangfq.daxian@gmail.com> wrote:
>
> kmemdup is introduced to duplicate a region of memory in a neat way.
> Rather than kmalloc/kzalloc + memcpy, which the programmer needs to
> write the size twice (sometimes lead to mistakes), kmemdup improves
> readability, leads to smaller code and also reduce the chances of mistakes.
> Suggestion to use kmemdup rather than using kmalloc/kzalloc + memcpy.
>

Pushed to my review and testing queue, thanks!

> Signed-off-by: Fuqian Huang <huangfq.daxian@gmail.com>
> ---
> Changes in v2:
>   - Fix a typo in commit message (memset -> memcpy)
>   - Split into two patches.
>
>  drivers/platform/x86/asus-wmi.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/drivers/platform/x86/asus-wmi.c b/drivers/platform/x86/asus-wmi.c
> index 9b18a184e0aa..472b317ad814 100644
> --- a/drivers/platform/x86/asus-wmi.c
> +++ b/drivers/platform/x86/asus-wmi.c
> @@ -260,12 +260,11 @@ static int asus_wmi_evaluate_method_agfn(const struct acpi_buffer args)
>          * Copy to dma capable address otherwise memory corruption occurs as
>          * bios has to be able to access it.
>          */
> -       input.pointer = kzalloc(args.length, GFP_DMA | GFP_KERNEL);
> +       input.pointer = kmemdup(args.pointer, args.length, GFP_DMA | GFP_KERNEL);
>         input.length = args.length;
>         if (!input.pointer)
>                 return -ENOMEM;
>         phys_addr = virt_to_phys(input.pointer);
> -       memcpy(input.pointer, args.pointer, args.length);
>
>         status = asus_wmi_evaluate_method(ASUS_WMI_METHODID_AGFN,
>                                         phys_addr, 0, &retval);
> --
> 2.11.0
>

Patch
diff mbox series

diff --git a/drivers/platform/x86/asus-wmi.c b/drivers/platform/x86/asus-wmi.c
index 9b18a184e0aa..472b317ad814 100644
--- a/drivers/platform/x86/asus-wmi.c
+++ b/drivers/platform/x86/asus-wmi.c
@@ -260,12 +260,11 @@  static int asus_wmi_evaluate_method_agfn(const struct acpi_buffer args)
 	 * Copy to dma capable address otherwise memory corruption occurs as
 	 * bios has to be able to access it.
 	 */
-	input.pointer = kzalloc(args.length, GFP_DMA | GFP_KERNEL);
+	input.pointer = kmemdup(args.pointer, args.length, GFP_DMA | GFP_KERNEL);
 	input.length = args.length;
 	if (!input.pointer)
 		return -ENOMEM;
 	phys_addr = virt_to_phys(input.pointer);
-	memcpy(input.pointer, args.pointer, args.length);
 
 	status = asus_wmi_evaluate_method(ASUS_WMI_METHODID_AGFN,
 					phys_addr, 0, &retval);