This patch ports the kprobe-based event tracer to powerpc. This patch
is based on x86 port. This brings powerpc on par with x86.
Signed-off-by: NMahesh Salgaonkar <mahesh@linux.vnet.ibm.com>
Acked-by: NMasami Hiramatsu <mhiramat@redhat.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Another fix for the extended ptrace patches in the -next tree.

The handling of breakpoints and watchpoints is inconsistent.  When a
breakpoint or watchpoint is hit, the interrupt handler is clearing the
proper bits in the dbcr* registers, but leaving the dac* and iac* registers
alone.  The ptrace code to delete the break/watchpoints checks the dac* and
iac* registers for zero to determine if they are enabled.  Instead, they
should check the dbcr* bits.
Signed-off-by: NDave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

powerpc/booke: Fix a couple typos in the advanced ptrace code

Found and fixed a couple typos in the advanced ptrace patches.
(These patches are currently in benh's next tree.)
Signed-off-by: NDave Kleikamp <shaggy@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: linuxppc-dev list <Linuxppc-dev@ozlabs.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

powerpc/booke: Add support for advanced debug registers

From: Dave Kleikamp <shaggy@linux.vnet.ibm.com>

Based on patches originally written by Torez Smith.

This patch defines context switch and trap related functionality
for BookE specific Debug Registers. It adds support to ptrace()
for setting and getting BookE related Debug Registers
Signed-off-by: NDave Kleikamp <shaggy@linux.vnet.ibm.com>
Cc: Torez Smith  <lnxtorez@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: David Gibson <dwg@au1.ibm.com>
Cc: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Sergio Durigan Junior <sergiodj@br.ibm.com>
Cc: Thiago Jung Bauermann <bauerman@br.ibm.com>
Cc: linuxppc-dev list <Linuxppc-dev@ozlabs.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

powerpc: Extended ptrace interface

From: Dave Kleikamp <shaggy@linux.vnet.ibm.com>

Based on patches originally written by Torez Smith.

Add a new extended ptrace interface so that user-space has a single
interface for powerpc, without having to know the specific layout
of the debug registers.

Implement:
PPC_PTRACE_GETHWDEBUGINFO
PPC_PTRACE_SETHWDEBUG
PPC_PTRACE_DELHWDEBUG
Signed-off-by: NDave Kleikamp <shaggy@linux.vnet.ibm.com>
Acked-by: NDavid Gibson <dwg@au1.ibm.com>
Cc: Torez Smith  <lnxtorez@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Cc: Kumar Gala <galak@kernel.crashing.org>
Cc: Sergio Durigan Junior <sergiodj@br.ibm.com>
Cc: Thiago Jung Bauermann <bauerman@br.ibm.com>
Cc: linuxppc-dev list <Linuxppc-dev@ozlabs.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

powerpc/booke: Introduce new CONFIG options for advanced debug registers

From: Dave Kleikamp <shaggy@linux.vnet.ibm.com>

Introduce new config options to simplify the ifdefs pertaining to the
advanced debug registers for booke and 40x processors:

CONFIG_PPC_ADV_DEBUG_REGS - boolean: true for dac-based processors
CONFIG_PPC_ADV_DEBUG_IACS - number of IAC registers
CONFIG_PPC_ADV_DEBUG_DACS - number of DAC registers
CONFIG_PPC_ADV_DEBUG_DVCS - number of DVC registers
CONFIG_PPC_ADV_DEBUG_DAC_RANGE - DAC ranges supported

Beginning conservatively, since I only have the facilities to test 440
hardware.  I believe all 40x and booke platforms support at least 2 IAC
and 2 DAC registers.  For 440, 4 IAC and 2 DVC registers are enabled, as
well as the DAC ranges.
Signed-off-by: NDave Kleikamp <shaggy@linux.vnet.ibm.com>
Acked-by: NDavid Gibson <dwg@au1.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

On booke processors, gdb is seeing spurious SIGTRAPs when setting a
watchpoint.

user_disable_single_step() simply quits when the DAC is non-zero.  It should
be clearing the DBCR0_IC and DBCR0_BT bits from the dbcr0 register and
TIF_SINGLESTEP from the thread flag.
Signed-off-by: NDave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Reworked by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

This adds block-step support on powerpc, including a PTRACE_SINGLEBLOCK
request for ptrace.

The BookE implementation is tweaked to fire a single step after a
block step in order to mimmic the server behaviour.
Signed-off-by: NRoland McGrath <roland@redhat.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

In PTRACE_GET/SETVSRREGS, we should be using the thread we are
ptracing rather than current.
Signed-off-by: NMichael Neuling <mikey@neuling.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

Fix cut-and-paste error in the size setting for ptrace buffers for VSX.
Signed-off-by: NMichael Neuling <mikey@neuling.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

This changes powerpc syscall tracing to use the new tracehook.h entry
points.  There is no change, only cleanup.

In addition, the assembly changes allow do_syscall_trace_enter() to
abort the syscall without losing the information about the original
r0 value.
Signed-off-by: NRoland McGrath <roland@redhat.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

* CONFIG_BOOKE is selected by CONFIG_44x so we dont need both
* Fixed a few comments
* Go back to only using DBCR0_IDM to determine if we are using
  debug resources.
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

* CONFIG_BOOKE is selected by CONFIG_44x so we dont need both
* Fixed a few comments
* Go back to only using DBCR0_IDM to determine if we are using
  debug resources.
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>

This patch implements support for HW based watchpoint via the
DBSR_DAC (Data Address Compare) facility of the BookE processors.

It does so by interfacing with the existing DABR breakpoint code
and adding the necessary bits and pieces for the new bits to
be properly set or cleared
Signed-off-by: NLuis Machado <luisgpm@br.ibm.com>
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>

This correctly hooks the VSX dump into Roland McGrath core file
infrastructure.  It adds the VSX dump information as an additional elf
note in the core file (after talking more to the tool chain/gdb guys).
This also ensures the formats are consistent between signals, ptrace
and core files.
Signed-off-by: NMichael Neuling <mikey@neuling.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

This patch extends the floating point save and restore code to use the
VSX load/stores when VSX is available.  This will make FP context
save/restore marginally slower on FP only code, when VSX is available,
as it has to load/store 128bits rather than just 64bits.

Mixing FP, VMX and VSX code will get constant architected state.

The signals interface is extended to enable access to VSR 0-31
doubleword 1 after discussions with tool chain maintainers.  Backward
compatibility is maintained.

The ptrace interface is also extended to allow access to VSR 0-31 full
registers.
Signed-off-by: NMichael Neuling <mikey@neuling.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

The layout of the new VSR registers and how they overlap on top of the
legacy FPR and VR registers is:

                   VSR doubleword 0               VSR doubleword 1
          ----------------------------------------------------------------
  VSR[0]  |             FPR[0]            |                              |
          ----------------------------------------------------------------
  VSR[1]  |             FPR[1]            |                              |
          ----------------------------------------------------------------
          |              ...              |                              |
          |              ...              |                              |
          ----------------------------------------------------------------
  VSR[30] |             FPR[30]           |                              |
          ----------------------------------------------------------------
  VSR[31] |             FPR[31]           |                              |
          ----------------------------------------------------------------
  VSR[32] |                             VR[0]                            |
          ----------------------------------------------------------------
  VSR[33] |                             VR[1]                            |
          ----------------------------------------------------------------
          |                              ...                             |
          |                              ...                             |
          ----------------------------------------------------------------
  VSR[62] |                             VR[30]                           |
          ----------------------------------------------------------------
  VSR[63] |                             VR[31]                           |
          ----------------------------------------------------------------

VSX has 64 128bit registers.  The first 32 regs overlap with the FP
registers and hence extend them with and additional 64 bits.  The
second 32 regs overlap with the VMX registers.

This commit introduces the thread_struct changes required to reflect
this register layout.  Ptrace and signals code is updated so that the
floating point registers are correctly accessed from the thread_struct
when CONFIG_VSX is enabled.
Signed-off-by: NMichael Neuling <mikey@neuling.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

We are going to change where the floating point registers are stored
in the thread_struct, so in preparation add some macros to access the
floating point registers.  Update all code to use these new macros.
Signed-off-by: NMichael Neuling <mikey@neuling.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

The PTRACE_SETREGS request was only recently added on powerpc,
and gdb does not use it.  So it slipped through without getting
all the testing it should have had.

The user_regset changes had a simple bug in storing to all of
the 32-bit general registers block on 64-bit kernels.  This bug
only comes up with PTRACE_SETREGS, not PPC_PTRACE_SETREGS.
It causes a BUG_ON to hit, so this fix needs to go in ASAP.
Signed-off-by: NRoland McGrath <roland@redhat.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

This makes the SPE register data appear in ELF core dumps, using the
new n_type value NT_PPC_SPE (0x101).  This new note type is not used
by any consumers of core files yet, but support can be added.  I don't
even have any hardware with SPE capabilities, so I've never seen such
a note.  But this demonstrates how simple it is to export register
information in core dumps when the user_regset style is used for the
low-level code.
Signed-off-by: NRoland McGrath <roland@redhat.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Now that ptrace_request handles these, we can drop some more boilerplate.
Signed-off-by: NRoland McGrath <roland@redhat.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

This replaces all the code for powerpc PTRACE_*REGS* requests with
simple calls to copy_regset_from_user and copy_regset_to_user.  All
the ptrace formats are either the whole corresponding user_regset
format (core dump format) or a leading subset of it, so we can get
rid of all the remaining embedded knowledge of both those layouts
and of the internal data structures they correspond to.  Only the
user_regset accessors need to implement that.
Signed-off-by: NRoland McGrath <roland@redhat.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

This extends task_user_regset_view CONFIG_PPC64 with support for the
32-bit view of register state, compatible with what a CONFIG_PPC32
kernel provides.  This will enable generic machine-independent code to
access user-mode threads' registers for debugging and dumping.
Signed-off-by: NRoland McGrath <roland@redhat.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

This provides the task_user_regset_view entry point and support for
all the native-mode (64 on CONFIG_PPC64, 32 on CONFIG_PPC32) thread
register state.  This will enable generic machine-independent code to
access user-mode threads' registers for debugging and dumping.
Signed-off-by: NRoland McGrath <roland@redhat.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

This implements user_regset-style accessors for the powerpc general
registers.  In the future these functions will be the only place that
needs to understand the user_regset layout (core dump format) and how
it maps to the internal representation of user thread state.
Signed-off-by: NRoland McGrath <roland@redhat.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

This isolates the ptrace code for the special-case registers msr and trap
from the ptrace-layout dispatch code.  This should inline away completely.
It cleanly separates the low-level machine magic that has to be done for
deep reasons, from the superficial details of the ptrace interface.
Signed-off-by: NRoland McGrath <roland@redhat.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

This implements user_regset-style accessors for the powerpc SPE data,
and rewrites the existing ptrace code in terms of those calls.
Signed-off-by: NRoland McGrath <roland@redhat.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

This implements user_regset-style accessors for the powerpc Altivec data,
and rewrites the existing ptrace code in terms of those calls.
Signed-off-by: NRoland McGrath <roland@redhat.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

This implements user_regset-style accessors for the powerpc FPU data,
and rewrites the existing ptrace code in terms of those calls.
Signed-off-by: NRoland McGrath <roland@redhat.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

This removes the handling for PTRACE_CONT et al from the powerpc
ptrace code, so it uses the new generic code via ptrace_request.
Signed-off-by: NRoland McGrath <roland@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

This defines the new standard arch_has_single_step macro.  It makes the
existing set_single_step and clear_single_step entry points global, and
renames them to the new standard names user_enable_single_step and
user_disable_single_step, respectively.
Signed-off-by: NRoland McGrath <roland@redhat.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>

Identical handlers of PTRACE_DETACH go into ptrace_request().
Not touching compat code.
Not touching archs that don't call ptrace_request.
Signed-off-by: NAlexey Dobriyan <adobriyan@sw.ru>
Acked-by: NChristoph Hellwig <hch@infradead.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This restores the CHECK_FULL_REGS sanity check to every place that can
access the nonvolatile GPRs for ptrace.  This is already done for
native-bitwidth PTRACE_PEEKUSR, but was omitted for many other cases
(32-bit ptrace, PTRACE_GETREGS, etc.); I think there may have been more
uniform checks before that were lost in the recent cleanup of GETREGS et al.
Signed-off-by: NRoland McGrath <roland@redhat.com>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

Make it so that SPE support can be determined at runtime.  This is similiar
to how we handle AltiVec.  This allows us to have SPE support built in and
work on processors with and without SPE.
Signed-off-by: NKumar Gala <galak@kernel.crashing.org>

Identical implementations of PTRACE_POKEDATA go into generic_ptrace_pokedata()
function.

AFAICS, fix bug on xtensa where successful PTRACE_POKEDATA will nevertheless
return EPERM.
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Identical implementations of PTRACE_PEEKDATA go into generic_ptrace_peekdata()
function.
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Allow ptrace to set dabr in the thread structure for both 32 and 64 bits,
though only 64 bits actually uses that field, it's actually defined in both.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

One of the gratuitous difference between 32 and 64-bit ptrace is
whether you can whack the MSR:FE0 and FE1 bits from ptrace.  This
patch forbids it unconditionally.  In addition, the 64-bit kernels
used to return the exception mode in the MSR on reads, but 32-bit
kernels didn't.  This patch makes it return those bits on both.

Finally, since ptrace-ppc32.h and ptrace-ppc64.h are mostly empty now, and
since the previous patch made ptrace32.c no longer need the MSR_DEBUGCHANGE
definition, we just remove those 2 files and move back the remaining bits
to ptrace.c (they were short lived heh ?).
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

This patch allows a ptracer to write to the "trap" and "orig_r3" words
of the pt_regs.

This, along with a subsequent patch to the signal restart code, should
enable gdb to properly handle syscall restarting after executing a separate
function (at least when there's no restart block).

This patch also removes ptrace32.c code toying directly with the registers
and makes it use the ptrace_get/put_reg() accessors for everything so that
the logic for checking what is permitted is in only one place.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>

CHECK_FULL_REGS() exist on both 32 and 64 bits, so there's no need
to make it conditional on CONFIG_PPC32.
Signed-off-by: NBenjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: NPaul Mackerras <paulus@samba.org>