1 files changed, 90 insertions, 0 deletions
diff --git a/include/linux/elfnote.h b/include/linux/elfnote.h
new file mode 100644
index 000000000000..67396db141e8
--- /dev/null
+++ b/include/linux/elfnote.h
@@ -0,0 +1,90 @@
+#ifndef _LINUX_ELFNOTE_H
+#define _LINUX_ELFNOTE_H
+/*
+ * Helper macros to generate ELF Note structures, which are put into a
+ * PT_NOTE segment of the final vmlinux image.  These are useful for
+ * including name-value pairs of metadata into the kernel binary (or
+ * modules?) for use by external programs.
+ *
+ * Each note has three parts: a name, a type and a desc.  The name is
+ * intended to distinguish the note's originator, so it would be a
+ * company, project, subsystem, etc; it must be in a suitable form for
+ * use in a section name.  The type is an integer which is used to tag
+ * the data, and is considered to be within the "name" namespace (so
+ * "FooCo"'s type 42 is distinct from "BarProj"'s type 42).  The
+ * "desc" field is the actual data.  There are no constraints on the
+ * desc field's contents, though typically they're fairly small.
+ *
+ * All notes from a given NAME are put into a section named
+ * .note.NAME.  When the kernel image is finally linked, all the notes
+ * are packed into a single .notes section, which is mapped into the
+ * PT_NOTE segment.  Because notes for a given name are grouped into
+ * the same section, they'll all be adjacent the output file.
+ *
+ * This file defines macros for both C and assembler use.  Their
+ * syntax is slightly different, but they're semantically similar.
+ *
+ * See the ELF specification for more detail about ELF notes.
+ */
+#ifdef __ASSEMBLER__
+/*
+ * Generate a structure with the same shape as Elf{32,64}_Nhdr (which
+ * turn out to be the same size and shape), followed by the name and
+ * desc data with appropriate padding.  The 'desctype' argument is the
+ * assembler pseudo op defining the type of the data e.g. .asciz while
+ * 'descdata' is the data itself e.g.  "hello, world".
+ *
+ * e.g. ELFNOTE(XYZCo, 42, .asciz, "forty-two")
+ *      ELFNOTE(XYZCo, 12, .long, 0xdeadbeef)
+ */
+#define ELFNOTE(name, type, desctype, descdata) \
+.pushsection .note.name                 ;       \
+  .align 4                              ;       \
+  .long 2f - 1f         /* namesz */    ;       \
+  .long 4f - 3f         /* descsz */    ;       \
+  .long type                            ;       \
+1:.asciz "name"                         ;       \
+2:.align 4                              ;       \
+3:desctype descdata                     ;       \
+4:.align 4                              ;       \
+.popsection                             ;
+#else   /* !__ASSEMBLER__ */
+#include <linux/elf.h>
+/*
+ * Use an anonymous structure which matches the shape of
+ * Elf{32,64}_Nhdr, but includes the name and desc data.  The size and
+ * type of name and desc depend on the macro arguments.  "name" must
+ * be a literal string, and "desc" must be passed by value.  You may
+ * only define one note per line, since __LINE__ is used to generate
+ * unique symbols.
+ */
+#define _ELFNOTE_PASTE(a,b)     a##b
+#define _ELFNOTE(size, name, unique, type, desc)                        \
+        static const struct {                                           \
+                struct elf##size##_note _nhdr;                          \
+                unsigned char _name[sizeof(name)]                       \
+                __attribute__((aligned(sizeof(Elf##size##_Word))));     \
+                typeof(desc) _desc                                      \
+                             __attribute__((aligned(sizeof(Elf##size##_Word)))); \
+        } _ELFNOTE_PASTE(_note_, unique)                                \
+                __attribute_used__                                      \
+                __attribute__((section(".note." name),                  \
+                               aligned(sizeof(Elf##size##_Word)),       \
+                               unused)) = {                             \
+                {                                                       \
+                        sizeof(name),                                   \
+                        sizeof(desc),                                   \
+                        type,                                           \
+                },                                                      \
+                name,                                                   \
+                desc                                                    \
+        }
+#define ELFNOTE(size, name, type, desc)         \
+        _ELFNOTE(size, name, __LINE__, type, desc)
+#define ELFNOTE32(name, type, desc) ELFNOTE(32, name, type, desc)
+#define ELFNOTE64(name, type, desc) ELFNOTE(64, name, type, desc)
+#endif  /* __ASSEMBLER__ */
+#endif /* _LINUX_ELFNOTE_H */

diff --git a/include/linux/elfnote.h b/include/linux/elfnote.h new file mode 100644 index 000000000000..67396db141e8 --- /dev/null +++ b/include/linux/elfnote.h
@@ -0,0 +1,90 @@
	1	#ifndef _LINUX_ELFNOTE_H
	2	#define _LINUX_ELFNOTE_H
	3	/*
	4	* Helper macros to generate ELF Note structures, which are put into a
	5	* PT_NOTE segment of the final vmlinux image. These are useful for
	6	* including name-value pairs of metadata into the kernel binary (or
	7	* modules?) for use by external programs.
	8	*
	9	* Each note has three parts: a name, a type and a desc. The name is
	10	* intended to distinguish the note's originator, so it would be a
	11	* company, project, subsystem, etc; it must be in a suitable form for
	12	* use in a section name. The type is an integer which is used to tag
	13	* the data, and is considered to be within the "name" namespace (so
	14	* "FooCo"'s type 42 is distinct from "BarProj"'s type 42). The
	15	* "desc" field is the actual data. There are no constraints on the
	16	* desc field's contents, though typically they're fairly small.
	17	*
	18	* All notes from a given NAME are put into a section named
	19	* .note.NAME. When the kernel image is finally linked, all the notes
	20	* are packed into a single .notes section, which is mapped into the
	21	* PT_NOTE segment. Because notes for a given name are grouped into
	22	* the same section, they'll all be adjacent the output file.
	23	*
	24	* This file defines macros for both C and assembler use. Their
	25	* syntax is slightly different, but they're semantically similar.
	26	*
	27	* See the ELF specification for more detail about ELF notes.
	28	*/
	29
	30	#ifdef __ASSEMBLER__
	31	/*
	32	* Generate a structure with the same shape as Elf{32,64}_Nhdr (which
	33	* turn out to be the same size and shape), followed by the name and
	34	* desc data with appropriate padding. The 'desctype' argument is the
	35	* assembler pseudo op defining the type of the data e.g. .asciz while
	36	* 'descdata' is the data itself e.g. "hello, world".
	37	*
	38	* e.g. ELFNOTE(XYZCo, 42, .asciz, "forty-two")
	39	* ELFNOTE(XYZCo, 12, .long, 0xdeadbeef)
	40	*/
	41	#define ELFNOTE(name, type, desctype, descdata) \
	42	.pushsection .note.name ; \
	43	.align 4 ; \
	44	.long 2f - 1f /* namesz */ ; \
	45	.long 4f - 3f /* descsz */ ; \
	46	.long type ; \
	47	1:.asciz "name" ; \
	48	2:.align 4 ; \
	49	3:desctype descdata ; \
	50	4:.align 4 ; \
	51	.popsection ;
	52	#else /* !__ASSEMBLER__ */
	53	#include <linux/elf.h>
	54	/*
	55	* Use an anonymous structure which matches the shape of
	56	* Elf{32,64}_Nhdr, but includes the name and desc data. The size and
	57	* type of name and desc depend on the macro arguments. "name" must
	58	* be a literal string, and "desc" must be passed by value. You may
	59	* only define one note per line, since __LINE__ is used to generate
	60	* unique symbols.
	61	*/
	62	#define _ELFNOTE_PASTE(a,b) a##b
	63	#define _ELFNOTE(size, name, unique, type, desc) \
	64	static const struct { \
	65	struct elf##size##_note _nhdr; \
	66	unsigned char _name[sizeof(name)] \
	67	__attribute__((aligned(sizeof(Elf##size##_Word)))); \
	68	typeof(desc) _desc \
	69	__attribute__((aligned(sizeof(Elf##size##_Word)))); \
	70	} _ELFNOTE_PASTE(_note_, unique) \
	71	__attribute_used__ \
	72	__attribute__((section(".note." name), \
	73	aligned(sizeof(Elf##size##_Word)), \
	74	unused)) = { \
	75	{ \
	76	sizeof(name), \
	77	sizeof(desc), \
	78	type, \
	79	}, \
	80	name, \
	81	desc \
	82	}
	83	#define ELFNOTE(size, name, type, desc) \
	84	_ELFNOTE(size, name, __LINE__, type, desc)
	85
	86	#define ELFNOTE32(name, type, desc) ELFNOTE(32, name, type, desc)
	87	#define ELFNOTE64(name, type, desc) ELFNOTE(64, name, type, desc)
	88	#endif /* __ASSEMBLER__ */
	89
	90	#endif /* _LINUX_ELFNOTE_H */