Copy stable/10@r272459 to releng/10.1 as part of
the 10.1-RELEASE process.

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

MFC r270798:
Process STT_GNU_IFUNC when doing non-plt relocations.

MFC r270802:
Only do the second pass over non-plt relocations when the first pass
found IFUNCs.

Approved by: re (gjb)

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

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

Fix several problems with our ELF filters implementation.

Do not relocate twice an object which happens to be needed by loaded
binary (or dso) and some filtee opened due to symbol resolution when
relocating need objects. Record the state of the relocation
processing in Obj_Entry and short-circuit relocate_objects() if
current object already processed.

Do not call constructors for filtees loaded during the early
relocation processing before image is initialized enough to run
user-provided code. Filtees are loaded using dlopen_object(), which
normally performs relocation and initialization. If filtee is
lazy-loaded during the relocation of dso needed by the main object,
dlopen_object() runs too earlier, when most runtime services are not
yet ready.

Postpone the constructors call to the time when main binary and
depended libraries constructors are run, passing the new flag
RTLD_LO_EARLY to dlopen_object(). Symbol lookups callers inform
symlook_* functions about early stage of initialization with
SYMLOOK_EARLY. Pass flags through all functions participating in
object relocation.

Use the opportunity and fix flags argument to find_symdef() in
arch-specific reloc.c to use proper name SYMLOOK_IN_PLT instead of
true, which happen to have the same numeric value.

Reported and tested by: theraven
Reviewed by: kan
MFC after: 2 weeks

- Switch to saving non-offseted pointer to TLS block in order too keep things simple

Add handlers for TLS-related relocation entries

Remove debug output

Switch MIPS TLS implementation to Variant I

Fix debug output for MIPS part of rtld

Spelling fixes for libexec/

Add support for STT_GNU_IFUNC and R_MACHINE_IRELATIVE GNU extensions to
rtld on 386 and amd64. This adds runtime bits neccessary for the use
of the dispatch functions from the dynamically-linked executables and
shared libraries.

To allow use of external references from the dispatch function, resolution
of the R_MACHINE_IRESOLVE relocations in PLT is postponed until GOT entries
for PLT are prepared, and normal resolution of the GOT entries is finished.
Similar to how it is done by GNU, IRELATIVE relocations are resolved in
advance, instead of normal lazy handling for PLT.

Move the init_pltgot() call before the relocations for the object are
processed.

MFC after: 3 weeks

Implement support for ELF filters in rtld. Both normal and auxillary
filters are implemented.

Filtees are loaded on demand, unless LD_LOADFLTR environment variable
is set or -z loadfltr was specified during the linking. This forces
rtld to upgrade read-locked rtld_bind_lock to write lock when it
encounters an object with filter during symbol lookup.

Consolidate common arguments of the symbol lookup functions in the
SymLook structure. Track the state of the rtld locks in the
RtldLockState structure. Pass local RtldLockState through the rtld
symbol lookup calls to allow lock upgrades.

Reviewed by: kan
Tested by: Mykola Dzham <i levsha me>, nwhitehorn (powerpc)

Add parentheses around the argument 'x' used in the __bswapXX(x) macros. Revert
r211130 in favor of this more general fix.

This fixes a compilation error for mips 64-bit little endian build.
libexec/rtld-elf/mips/reloc.c:196: warning: right shift count >= width of type

Suggested by: stefanf, jchandra, bde

Fix compilation error for 64-bit little endian build:
libexec/rtld-elf/mips/reloc.c:196: warning: right shift count >= width of type

When the expression '(r_info) >> 32' was passed to bswap32() it was promptly
changed to '(uint32_t)(r_info) >> 32' which is not what we intended.

64 bit support for MIPS rtld.

- Handle the case where pltgot[1] is 64 bit.
- use 'ifdef __mips_n64' instead of 'ELFSIZE == 64' to detect 64 bit compile.

Updated rtld for n32 support.

Submitted by: jmallet@
Obtained from: NetBSD

This code has no copyright. It is fairly obvious to me that we're a
derivitive of NetBSD's mips_reloc.c, so pull in the copyright notice
from there.

Also, a minor tweak to load/store pointers. Other changes from NetBSD
likely would be useful too...

Obtained from: NetBSD

MFp4: Fix a bug in the mips relocation code that prevents shared images
from working.

From p4 filelog of the upstream file in p4

//depot/projects/mips2-jnpr/src/libexec/rtld-elf/mips/reloc.c
... #6 change 140737 edit on 2008/04/27 by gonzo@gonzo_jeeves (text+ko)

o Looks like handler for R_MIPS_REL32 brought by CS 137942
is broken for tradmips. Code from NetBSD's
libexec/ld.elf_so/arch/mips/mips_reloc.c works just fine.

... #3 change 137942 edit on 2008/03/17 by rrs@rrs-mips2-jnpr (text+ko)

Any relocation symbol lookup if its 0. It looks like
this is the way the compiler indicates you need to
look in another shared library. When we hit these
as we relocate a object we will do the symbol
lookups and setup the relocation table with the
right value.

Submitted by: rrs@, gonzo@

MFp4: Add mips support for dynamic linking.

This code came from the merged mips2 and Juniper mips repositories.
Warner Losh, Randall Seager, Oleksandr Tymoshenko and Olivier Houchard
worked to merge, debug and integrate this code. This code may also
contain code derived from NetBSD.