linux err: make ERR_PTR/PTR_ERR architecture specific

This patch changes ERR_PTR/PTR_ERR to use CONFIG_ERR_PTR_OFFSET to map
errno values into a pointer region that cannot contain valid pointers.

IS_ERR and IS_ERR_OR_NULL have to be converted to use PTR_ERR, too,
for this to work.

Signed-off-by: Simon Goldschmidt <simon.k.r.goldschmidt@gmail.com>

diff --git a/include/linux/err.h b/include/linux/err.h
index 22e5756..5ede824 100644 (file)
--- a/include/linux/err.h
+++ b/include/linux/err.h
@@ -23,22 +23,22 @@
 
 static inline void *ERR_PTR(long error)
 {
-       return (void *) error;
+       return (void *)(CONFIG_ERR_PTR_OFFSET + error);
 }
 
 static inline long PTR_ERR(const void *ptr)
 {
-       return (long) ptr;
+       return ((long)ptr - CONFIG_ERR_PTR_OFFSET);
 }
 
 static inline long IS_ERR(const void *ptr)
 {
-       return IS_ERR_VALUE((unsigned long)ptr);
+       return IS_ERR_VALUE((unsigned long)PTR_ERR(ptr));
 }
 
 static inline bool IS_ERR_OR_NULL(const void *ptr)
 {
-       return !ptr || IS_ERR_VALUE((unsigned long)ptr);
+       return !ptr || IS_ERR_VALUE((unsigned long)PTR_ERR(ptr));
 }
 
 /**