ARM: add support for hw-breakpoints [v5]

This is version 5 of the patches originally posted at:

v1.) http://lists.infradead.org/pipermail/linux-arm-kernel/2010-February/009084.html
v2.) http://lists.infradead.org/pipermail/linux-arm-kernel/2010-March/011170.html
v3.) http://lists.infradead.org/pipermail/linux-arm-kernel/2010-June/017680.html
v4.) http://lists.infradead.org/pipermail/linux-arm-kernel/2010-July/019882.html

Changes from v4 include:
- isb() after writing to breakpoint registers to ensure that the update takes place.
- Rebased onto 2.6.35

As with v4, these patches have been shown to work with GDB using the patches posted here:

http://sourceware.org/ml/gdb-patches/2010-07/msg00110.html

Will Deacon (4):
ARM: hw-breakpoint: add mechanism for hooking into prefetch aborts
ARM: hw-breakpoint: add ARM backend for the hw-breakpoint framework
ARM: hw-breakpoint: add new ptrace requests for hw-breakpoint
interaction
ARM: hw-breakpoint: add HAVE_HW_BREAKPOINT to Kconfig

 arch/arm/Kconfig                     |    1 +
 arch/arm/include/asm/hw_breakpoint.h |  117 ++++++
 arch/arm/include/asm/processor.h     |    4 +
 arch/arm/include/asm/ptrace.h        |    2 +
 arch/arm/include/asm/system.h        |    3 +
 arch/arm/kernel/Makefile             |    1 +
 arch/arm/kernel/hw_breakpoint.c      |  761 ++++++++++++++++++++++++++++++++++
 arch/arm/kernel/ptrace.c             |  223 ++++++++++
 arch/arm/mm/fault.c                  |   11 +
 9 files changed, 1123 insertions(+), 0 deletions(-)
 create mode 100644 arch/arm/include/asm/hw_breakpoint.h
 create mode 100644 arch/arm/kernel/hw_breakpoint.c