linux/arch/um/os-Linux/registers.c
Jeff Dike a5f6096c80 uml: floating point signal delivery fixes
Handle floating point state in across signals correctly.  UML/i386 needs to
know whether the host does PTRACE_[GS]ETFPXREGS, so an arch_init_registers
hook is added, which on x86_64 does nothing.

UML doesn't save and restore floating point registers on kernel entry and
exit, so they need to be copied between the host process and the sigcontext.
save_fpx_registers and restore_fpx_registers are added for this purpose.
save_fp_registers and restore_fp_registers already exist.

There was a bunch of floating point state conversion code in
arch/um/sys-i386/ptrace.c which isn't needed there, but is needed in signal.c,
so it is moved over.

The i386 code now distinguishes between fp and fpx state and handles them
correctly.  The x86_64 code just needs to copy state as-is between the host
process and the stack.  There are also some fixes there to pass the correct
address of the floating point state around.

Signed-off-by: Jeff Dike <jdike@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16 09:43:07 -07:00

58 lines
1.2 KiB
C

/*
* Copyright (C) 2004 PathScale, Inc
* Copyright (C) 2004 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
* Licensed under the GPL
*/
#include <errno.h>
#include <string.h>
#include <sys/ptrace.h>
#include "sysdep/ptrace.h"
#include "user.h"
/* This is set once at boot time and not changed thereafter */
static unsigned long exec_regs[MAX_REG_NR];
void init_thread_registers(struct uml_pt_regs *to)
{
memcpy(to->gp, exec_regs, sizeof(to->gp));
}
void save_registers(int pid, struct uml_pt_regs *regs)
{
int err;
err = ptrace(PTRACE_GETREGS, pid, 0, regs->gp);
if (err < 0)
panic("save_registers - saving registers failed, errno = %d\n",
errno);
}
void restore_registers(int pid, struct uml_pt_regs *regs)
{
int err;
err = ptrace(PTRACE_SETREGS, pid, 0, regs->gp);
if (err < 0)
panic("restore_registers - saving registers failed, "
"errno = %d\n", errno);
}
void init_registers(int pid)
{
int err;
err = ptrace(PTRACE_GETREGS, pid, 0, exec_regs);
if (err)
panic("check_ptrace : PTRACE_GETREGS failed, errno = %d",
errno);
arch_init_registers(pid);
}
void get_safe_registers(unsigned long *regs)
{
memcpy(regs, exec_regs, sizeof(exec_regs));
}