alistair23-linux/include/linux/prctl.h
Anton Blanchard 651d765d0b [PATCH] Add a prctl to change the endianness of a process.
This new prctl is intended for changing the execution mode of the
processor, on processors that support both a little-endian mode and a
big-endian mode.  It is intended for use by programs such as
instruction set emulators (for example an x86 emulator on PowerPC),
which may find it convenient to use the processor in an alternate
endianness mode when executing translated instructions.

Note that this does not imply the existence of a fully-fledged ABI for
both endiannesses, or of compatibility code for converting system
calls done in the non-native endianness mode.  The program is expected
to arrange for all of its system call arguments to be presented in the
native endianness.

Switching between big and little-endian mode will require some care in
constructing the instruction sequence for the switch.  Generally the
instructions up to the instruction that invokes the prctl system call
will have to be in the old endianness, and subsequent instructions
will have to be in the new endianness.

Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
2006-06-09 21:24:13 +10:00

63 lines
2.5 KiB
C

#ifndef _LINUX_PRCTL_H
#define _LINUX_PRCTL_H
/* Values to pass as first argument to prctl() */
#define PR_SET_PDEATHSIG 1 /* Second arg is a signal */
#define PR_GET_PDEATHSIG 2 /* Second arg is a ptr to return the signal */
/* Get/set current->mm->dumpable */
#define PR_GET_DUMPABLE 3
#define PR_SET_DUMPABLE 4
/* Get/set unaligned access control bits (if meaningful) */
#define PR_GET_UNALIGN 5
#define PR_SET_UNALIGN 6
# define PR_UNALIGN_NOPRINT 1 /* silently fix up unaligned user accesses */
# define PR_UNALIGN_SIGBUS 2 /* generate SIGBUS on unaligned user access */
/* Get/set whether or not to drop capabilities on setuid() away from uid 0 */
#define PR_GET_KEEPCAPS 7
#define PR_SET_KEEPCAPS 8
/* Get/set floating-point emulation control bits (if meaningful) */
#define PR_GET_FPEMU 9
#define PR_SET_FPEMU 10
# define PR_FPEMU_NOPRINT 1 /* silently emulate fp operations accesses */
# define PR_FPEMU_SIGFPE 2 /* don't emulate fp operations, send SIGFPE instead */
/* Get/set floating-point exception mode (if meaningful) */
#define PR_GET_FPEXC 11
#define PR_SET_FPEXC 12
# define PR_FP_EXC_SW_ENABLE 0x80 /* Use FPEXC for FP exception enables */
# define PR_FP_EXC_DIV 0x010000 /* floating point divide by zero */
# define PR_FP_EXC_OVF 0x020000 /* floating point overflow */
# define PR_FP_EXC_UND 0x040000 /* floating point underflow */
# define PR_FP_EXC_RES 0x080000 /* floating point inexact result */
# define PR_FP_EXC_INV 0x100000 /* floating point invalid operation */
# define PR_FP_EXC_DISABLED 0 /* FP exceptions disabled */
# define PR_FP_EXC_NONRECOV 1 /* async non-recoverable exc. mode */
# define PR_FP_EXC_ASYNC 2 /* async recoverable exception mode */
# define PR_FP_EXC_PRECISE 3 /* precise exception mode */
/* Get/set whether we use statistical process timing or accurate timestamp
* based process timing */
#define PR_GET_TIMING 13
#define PR_SET_TIMING 14
# define PR_TIMING_STATISTICAL 0 /* Normal, traditional,
statistical process timing */
# define PR_TIMING_TIMESTAMP 1 /* Accurate timestamp based
process timing */
#define PR_SET_NAME 15 /* Set process name */
#define PR_GET_NAME 16 /* Get process name */
/* Get/set process endian */
#define PR_GET_ENDIAN 19
#define PR_SET_ENDIAN 20
# define PR_ENDIAN_BIG 0
# define PR_ENDIAN_LITTLE 1 /* True little endian mode */
# define PR_ENDIAN_PPC_LITTLE 2 /* "PowerPC" pseudo little endian */
#endif /* _LINUX_PRCTL_H */