diff options
author | Srikant Patnaik | 2015-01-11 12:28:04 +0530 |
---|---|---|
committer | Srikant Patnaik | 2015-01-11 12:28:04 +0530 |
commit | 871480933a1c28f8a9fed4c4d34d06c439a7a422 (patch) | |
tree | 8718f573808810c2a1e8cb8fb6ac469093ca2784 /include/linux/elfnote.h | |
parent | 9d40ac5867b9aefe0722bc1f110b965ff294d30d (diff) | |
download | FOSSEE-netbook-kernel-source-871480933a1c28f8a9fed4c4d34d06c439a7a422.tar.gz FOSSEE-netbook-kernel-source-871480933a1c28f8a9fed4c4d34d06c439a7a422.tar.bz2 FOSSEE-netbook-kernel-source-871480933a1c28f8a9fed4c4d34d06c439a7a422.zip |
Moved, renamed, and deleted files
The original directory structure was scattered and unorganized.
Changes are basically to make it look like kernel structure.
Diffstat (limited to 'include/linux/elfnote.h')
-rw-r--r-- | include/linux/elfnote.h | 98 |
1 files changed, 98 insertions, 0 deletions
diff --git a/include/linux/elfnote.h b/include/linux/elfnote.h new file mode 100644 index 00000000..278e3ef0 --- /dev/null +++ b/include/linux/elfnote.h @@ -0,0 +1,98 @@ +#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_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 ; + +#define ELFNOTE(name, type, desc) \ + ELFNOTE_START(name, type, "") \ + desc ; \ + ELFNOTE_END + +#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) \ + __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 */ |