From:   Alejandro Colomar <alx.manpages@gmail.com>
To:     LKML <linux-kernel@vger.kernel.org>
Cc:     Alejandro Colomar <alx.manpages@gmail.com>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Arnd Bergmann <arnd@arndb.de>,
        Alexey Dobriyan <adobriyan@gmail.com>,
        Jani Nikula <jani.nikula@linux.intel.com>,
        Rasmus Villemoes <linux@rasmusvillemoes.dk>,
        Kees Cook <keescook@chromium.org>,
        Joe Perches <joe@perches.com>
Subject: [PATCH v2 08/20] Implement container_of_safe() in terms of container_of()
Date:   Sat, 20 Nov 2021 14:00:51 +0100
Message-Id: <20211120130104.185699-9-alx.manpages@gmail.com>
In-Reply-To: <20211120130104.185699-1-alx.manpages@gmail.com>
References: <20211119113644.1600-1-alx.manpages@gmail.com>
 <20211120130104.185699-1-alx.manpages@gmail.com>
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There's no more a need for the temporary variable __mptr,
since now it's only passed to functions that accept a 'const void *',
and everything can convert automatically to it,
reducing the need for the cast too.

Signed-off-by: Alejandro Colomar <alx.manpages@gmail.com>
---
 include/linux/container_of.h | 9 ++-------
 1 file changed, 2 insertions(+), 7 deletions(-)

diff --git a/include/linux/container_of.h b/include/linux/container_of.h
index 220990db7b61..03809348f333 100644
--- a/include/linux/container_of.h
+++ b/include/linux/container_of.h
@@ -30,12 +30,7 @@
  *
  * If IS_ERR_OR_NULL(ptr), ptr is returned unchanged.
  */
-#define container_of_safe(ptr, type, member) ({				\
-	void *__mptr = (void *)(ptr);					\
-	static_assert(__same_type(*(ptr), ((type *)0)->member) ||	\
-		      __same_type(*(ptr), void),			\
-		      "pointer type mismatch in container_of_safe()");	\
-	IS_ERR_OR_NULL(__mptr) ? ERR_CAST(__mptr) :			\
-		((type *)(__mptr - offsetof(type, member))); })
+#define container_of_safe(ptr, type, member) 				\
+	(IS_ERR_OR_NULL(ptr) ? ERR_CAST(ptr) : container_of(type, member))
 
 #endif	/* _LINUX_CONTAINER_OF_H */
-- 
2.33.1