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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 18:49:45 +0000
commit2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch)
tree848558de17fb3008cdf4d861b01ac7781903ce39 /include/linux/container_of.h
parentInitial commit. (diff)
downloadlinux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz
linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'include/linux/container_of.h')
-rw-r--r--include/linux/container_of.h40
1 files changed, 40 insertions, 0 deletions
diff --git a/include/linux/container_of.h b/include/linux/container_of.h
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--- /dev/null
+++ b/include/linux/container_of.h
@@ -0,0 +1,40 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _LINUX_CONTAINER_OF_H
+#define _LINUX_CONTAINER_OF_H
+
+#include <linux/build_bug.h>
+#include <linux/err.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); \
+ static_assert(__same_type(*(ptr), ((type *)0)->member) || \
+ __same_type(*(ptr), void), \
+ "pointer type mismatch in container_of()"); \
+ ((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); \
+ 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))); })
+
+#endif /* _LINUX_CONTAINER_OF_H */