I am also agree with Arnd Bergmann. We should use 'static inline function'
instead of macro to deal with error check.

On Tuesday 26 July 2016 05:09 PM, Arnd Bergmann wrote:

On Saturday, July 23, 2016 11:35:51 PM CEST Arvind Yadav wrote:

quoted

diff --git a/include/linux/err.h b/include/linux/err.h
index 1e35588..a42f942 100644
--- a/include/linux/err.h
+++ b/include/linux/err.h

@@ -19,6 +19,7 @@
  #ifndef __ASSEMBLY__
  
  #define IS_ERR_VALUE(x) unlikely((unsigned long)(void *)(x) >= (unsigned long)-MAX_ERRNO)
+#define IS_ERR_VALUE_U32(x) unlikely((unsigned int)(x) >= (unsigned int)-MAX_ERRNO)
  
  static inline void * __must_check ERR_PTR(long error)
  {

This doesn't really look like something we want to have as a generic
interface. The IS_ERR_VALUE() API is rather awkward already, and your
use seems specific to the cpu_muram_alloc() function.

How about something like

int cpm_muram_error(unsigned long addr)
{
	if (addr >= (unsigned long)-MAX_ERRNO)
		return addr;
	else
		return 0;
}

and then use that to check the value returned by the allocation
that is still an 'unsigned long', before assigning it to a 'u32'.

	Arnd