MFC r313493:
Define ELF_ST_VISIBILITY().

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

style(9)

Verified with: svn diff -x -Bbw elf_generic.h elf64.h

Implement ELF symbol versioning using GNU semantics. This code aims
to be compatible with symbol versioning support as implemented by
GNU libc and documented by http://people.redhat.com/~drepper/symbol-versioning
and LSB 3.0.

Implement dlvsym() function to allow lookups for a specific version of
a given symbol.

Make our ELF64 type definitions match standards. In particular this
means:
o Remove Elf64_Quarter,
o Redefine Elf64_Half to be 16-bit,
o Redefine Elf64_Word to be 32-bit,
o Add Elf64_Xword and Elf64_Sxword for 64-bit entities,
o Use Elf_Size in MI code to abstract the difference between
Elf32_Word and Elf64_Word.
o Add Elf_Ssize as the signed counterpart of Elf_Size.

MFC after: 2 weeks

Infrastructure tweaks to allow having both an Elf32 and an Elf64 executable
handler in the kernel at the same time. Also, allow for the
exec_new_vmspace() code to build a different sized vmspace depending on
the executable environment. This is a big help for execing i386 binaries
on ia64. The ELF exec code grows the ability to map partial pages when
there is a page size difference, eg: emulating 4K pages on 8K or 16K
hardware pages.

Flesh out the i386 emulation support for ia64. At this point, the only
binary that I know of that fails is cvsup, because the cvsup runtime
tries to execute code in pages not marked executable.

Obtained from: dfr (mostly, many tweaks from me).

Move the definition of ElfN_Hashelt to common headers. The only platform
which has a different definition for this is alpha.

$Id$ -> $FreeBSD$

The structure Elf_Note does not have 32 and 64 bit variants but always
has 32bit fields. This change allows FreeBSD/alpha to generate well-formed
ELF corefiles.

Reviewed by: John Polstra <jdp@polstra.com>

Add generic defines ELF_ARCH, ELF_CLASS, and ELF_DATA. These give
the relevant characteristics of the native machine, for building
and checking Elf_Ehdr structures.

Add structures to represent ELF "note" headers. Add defines for the
note types used in ELF core files.

Revamp the ELF include files to better support architecture-independent
applications. Here's how it works.

The kernel should include <machine/elf.h> to get the definitions
for the native architecture. It can reference the various ELF
structures with generic names like Elf_Sym, Elf_Shdr, etc. A define
__ELF_WORD_SIZE is also available with the value 32 or 64 as
appropriate for the native architecture.

Generic applications should include <elf.h>, which is just a wrapper
for <machine/elf.h>.

Applications such as object file dumpers that need to deal with
foreign ELF files can include <sys/elf32.h> and/or <sys/elf64.h>.
Both can be included from the same source file if desired. The
structure names must be referenced using wordsize-specific names
like Elf32_Sym, Elf64_Shdr, etc.

I haven't change the alpha stuff, but I haven't broken it either.