diff mbox series

[v2,1/2] err.h: Add ERR_PTR_PCPU(), PTR_ERR_PCPU() and IS_ERR_PCPU() macros

Message ID 20240818210235.33481-1-ubizjak@gmail.com (mailing list archive)
State New
Headers show
Series [v2,1/2] err.h: Add ERR_PTR_PCPU(), PTR_ERR_PCPU() and IS_ERR_PCPU() macros | expand

Commit Message

Uros Bizjak Aug. 18, 2024, 9:01 p.m. UTC
Add ERR_PTR_PCPU(), PTR_ERR_PCPU() and IS_ERR_PCPU() macros that
operate on pointers in the percpu address space.

These macros remove the need for (__force void *) function
argument casts (to avoid sparse -Wcast-from-as warnings).

The patch will also avoid future build errors due to pointer address
space mismatch with enabled strict percpu address space checks.

Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
---
v2: Implement as macros to avoid powerpc build failure
---
 include/linux/err.h | 9 +++++++++
 1 file changed, 9 insertions(+)

Comments

Catalin Marinas Aug. 22, 2024, 8:35 a.m. UTC | #1
On Sun, Aug 18, 2024 at 11:01:51PM +0200, Uros Bizjak wrote:
> Add ERR_PTR_PCPU(), PTR_ERR_PCPU() and IS_ERR_PCPU() macros that
> operate on pointers in the percpu address space.
> 
> These macros remove the need for (__force void *) function
> argument casts (to avoid sparse -Wcast-from-as warnings).
> 
> The patch will also avoid future build errors due to pointer address
> space mismatch with enabled strict percpu address space checks.
> 
> Signed-off-by: Uros Bizjak <ubizjak@gmail.com>
> Cc: Catalin Marinas <catalin.marinas@arm.com>
> Cc: Andrew Morton <akpm@linux-foundation.org>

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
diff mbox series

Patch

diff --git a/include/linux/err.h b/include/linux/err.h
index b5d9bb2a2349..a4dacd745fcf 100644
--- a/include/linux/err.h
+++ b/include/linux/err.h
@@ -41,6 +41,9 @@  static inline void * __must_check ERR_PTR(long error)
 	return (void *) error;
 }
 
+/* Return the pointer in the percpu address space. */
+#define ERR_PTR_PCPU(error) ((void __percpu *)(unsigned long)ERR_PTR(error))
+
 /**
  * PTR_ERR - Extract the error code from an error pointer.
  * @ptr: An error pointer.
@@ -51,6 +54,9 @@  static inline long __must_check PTR_ERR(__force const void *ptr)
 	return (long) ptr;
 }
 
+/* Read an error pointer from the percpu address space. */
+#define PTR_ERR_PCPU(ptr) (PTR_ERR((const void *)(__force const unsigned long)(ptr)))
+
 /**
  * IS_ERR - Detect an error pointer.
  * @ptr: The pointer to check.
@@ -61,6 +67,9 @@  static inline bool __must_check IS_ERR(__force const void *ptr)
 	return IS_ERR_VALUE((unsigned long)ptr);
 }
 
+/* Read an error pointer from the percpu address space. */
+#define IS_ERR_PCPU(ptr) (IS_ERR((const void *)(__force const unsigned long)(ptr)))
+
 /**
  * IS_ERR_OR_NULL - Detect an error pointer or a null pointer.
  * @ptr: The pointer to check.