/* elfnote.h COPYRIGHT FUJITSU LIMITED 2016 */
/* @ref.impl include/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.
 */
#ifndef __HEADER_ARM64_COMMON_ELFNOTE_H
#define __HEADER_ARM64_COMMON_ELFNOTE_H

#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_START(name, type, flags)        \
.pushsection .note.name, flags,@note    ;       \
  .balign 4                             ;       \
  .long 2f - 1f         /* namesz */    ;       \
  .long 4484f - 3f      /* descsz */    ;       \
  .long type                            ;       \
1:.asciz #name                          ;       \
2:.balign 4                             ;       \
3:

#define ELFNOTE_END                             \
4484:.balign 4                          ;       \
.popsection                             ;

#endif	/* __ASSEMBLER__ */

#endif	/* !__HEADER_ARM64_COMMON_ELFNOTE_H */