android_kernel_motorola_sm6225/arch/um/os-Linux/sys-i386/registers.c
Jeff Dike 2ace87b950 [PATCH] uml: error handling fixes
Blairsorblade noticed some confusion between our use of a system
call's return value and errno.  This patch fixes a number of related
bugs -
	using errno instead of a return value
	using a return value instead of errno
	forgetting to negate a error return to get a positive error code

Signed-off-by: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-05-01 18:17:44 -07:00

140 lines
3.2 KiB
C

/*
* Copyright (C) 2004 PathScale, Inc
* Licensed under the GPL
*/
#include <errno.h>
#include <string.h>
#include <setjmp.h>
#include "sysdep/ptrace_user.h"
#include "sysdep/ptrace.h"
#include "uml-config.h"
#include "skas_ptregs.h"
#include "registers.h"
#include "user.h"
/* These are set once at boot time and not changed thereafter */
static unsigned long exec_regs[HOST_FRAME_SIZE];
static unsigned long exec_fp_regs[HOST_FP_SIZE];
static unsigned long exec_fpx_regs[HOST_XFP_SIZE];
static int have_fpx_regs = 1;
void init_thread_registers(union uml_pt_regs *to)
{
memcpy(to->skas.regs, exec_regs, sizeof(to->skas.regs));
memcpy(to->skas.fp, exec_fp_regs, sizeof(to->skas.fp));
if(have_fpx_regs)
memcpy(to->skas.xfp, exec_fpx_regs, sizeof(to->skas.xfp));
}
/* XXX These need to use [GS]ETFPXREGS and copy_sc_{to,from}_user_skas needs
* to pass in a sufficiently large buffer
*/
int save_fp_registers(int pid, unsigned long *fp_regs)
{
if(ptrace(PTRACE_GETFPREGS, pid, 0, fp_regs) < 0)
return(-errno);
return(0);
}
int restore_fp_registers(int pid, unsigned long *fp_regs)
{
if(ptrace(PTRACE_SETFPREGS, pid, 0, fp_regs) < 0)
return(-errno);
return(0);
}
static int move_registers(int pid, int int_op, union uml_pt_regs *regs,
int fp_op, unsigned long *fp_regs)
{
if(ptrace(int_op, pid, 0, regs->skas.regs) < 0)
return(-errno);
if(ptrace(fp_op, pid, 0, fp_regs) < 0)
return(-errno);
return(0);
}
void save_registers(int pid, union uml_pt_regs *regs)
{
unsigned long *fp_regs;
int err, fp_op;
if(have_fpx_regs){
fp_op = PTRACE_GETFPXREGS;
fp_regs = regs->skas.xfp;
}
else {
fp_op = PTRACE_GETFPREGS;
fp_regs = regs->skas.fp;
}
err = move_registers(pid, PTRACE_GETREGS, regs, fp_op, fp_regs);
if(err)
panic("save_registers - saving registers failed, errno = %d\n",
-err);
}
void restore_registers(int pid, union uml_pt_regs *regs)
{
unsigned long *fp_regs;
int err, fp_op;
if(have_fpx_regs){
fp_op = PTRACE_SETFPXREGS;
fp_regs = regs->skas.xfp;
}
else {
fp_op = PTRACE_SETFPREGS;
fp_regs = regs->skas.fp;
}
err = move_registers(pid, PTRACE_SETREGS, regs, fp_op, fp_regs);
if(err)
panic("restore_registers - saving registers failed, "
"errno = %d\n", -err);
}
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);
errno = 0;
err = ptrace(PTRACE_GETFPXREGS, pid, 0, exec_fpx_regs);
if(!err)
return;
if(errno != EIO)
panic("check_ptrace : PTRACE_GETFPXREGS failed, errno = %d",
errno);
have_fpx_regs = 0;
err = ptrace(PTRACE_GETFPREGS, pid, 0, exec_fp_regs);
if(err)
panic("check_ptrace : PTRACE_GETFPREGS failed, errno = %d",
errno);
}
void get_safe_registers(unsigned long *regs, unsigned long *fp_regs)
{
memcpy(regs, exec_regs, HOST_FRAME_SIZE * sizeof(unsigned long));
if(fp_regs != NULL)
memcpy(fp_regs, exec_fp_regs,
HOST_FP_SIZE * sizeof(unsigned long));
}
void get_thread_regs(union uml_pt_regs *uml_regs, void *buffer)
{
struct __jmp_buf_tag *jmpbuf = buffer;
UPT_SET(uml_regs, EIP, jmpbuf->__jmpbuf[JB_PC]);
UPT_SET(uml_regs, UESP, jmpbuf->__jmpbuf[JB_SP]);
UPT_SET(uml_regs, EBP, jmpbuf->__jmpbuf[JB_BP]);
}