On Thu, 2021-10-07 at 18:44 +0300, Andy Shevchenko wrote:
kernel.h is being used as a dump for all kinds of stuff for a long time. Here is the attempt cleaning it up by splitting out container_of() and typeof_member() macros.
For time being include new header back to kernel.h to avoid twisted indirected includes for existing users.
IMO: this new file is missing 2 #include directives.
diff --git a/include/linux/container_of.h b/include/linux/container_of.h
[]
@@ -0,0 +1,37 @@ +/* SPDX-License-Identifier: GPL-2.0 */
And trivially: I'd prefer GPL-2.0-only
+#ifndef _LINUX_CONTAINER_OF_H +#define _LINUX_CONTAINER_OF_H
+#define typeof_member(T, m) typeof(((T*)0)->m)
+/**
- container_of - cast a member of a structure out to the containing structure
- @ptr: the pointer to the member.
- @type: the type of the container struct this is embedded in.
- @member: the name of the member within the struct.
- */
+#define container_of(ptr, type, member) ({ \
- void *__mptr = (void *)(ptr); \
- BUILD_BUG_ON_MSG(!__same_type(*(ptr), ((type *)0)->member) && \
!__same_type(*(ptr), void), \"pointer type mismatch in container_of()"); \
This is not a self-contained header as it requires #include <linux/build_bug.h> which should be at the top of this file.
- ((type *)(__mptr - offsetof(type, member))); })
+/**
- container_of_safe - cast a member of a structure out to the containing structure
- @ptr: the pointer to the member.
- @type: the type of the container struct this is embedded in.
- @member: the name of the member within the struct.
- If IS_ERR_OR_NULL(ptr), ptr is returned unchanged.
- */
+#define container_of_safe(ptr, type, member) ({ \
- void *__mptr = (void *)(ptr); \
- BUILD_BUG_ON_MSG(!__same_type(*(ptr), ((type *)0)->member) && \
!__same_type(*(ptr), void), \"pointer type mismatch in container_of()"); \- IS_ERR_OR_NULL(__mptr) ? ERR_CAST(__mptr) : \
((type *)(__mptr - offsetof(type, member))); })
And this requires
#include <linux/err.h>
+#endif /* _LINUX_CONTAINER_OF_H */