uml: use ptrace directly in libc code

Some register accessor cleanups -
	userspace() was calling restore_registers and save_registers for no
reason, since userspace() is on the libc side of the house, and these
add no value over calling ptrace directly
	init_thread_registers and get_safe_registers were the same thing,
so init_thread_registers is gone

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>

1 files changed, 8 insertions, 3 deletions

diff --git a/arch/um/os-Linux/skas/process.c b/arch/um/os-Linux/skas/process.c
index 2cc2071112bc..7dc24e3cb190 100644
--- a/arch/um/os-Linux/skas/process.c
+++ b/arch/um/os-Linux/skas/process.c
@@ -300,7 +300,9 @@ void userspace(struct uml_pt_regs *regs)
         nsecs += os_nsecs();
 
         while (1) {
-                restore_registers(pid, regs);
+                if (ptrace(PTRACE_SETREGS, pid, 0, regs->gp))
+                        panic("userspace - PTRACE_SETREGS failed, "
+                              "errno = %d\n", errno);
 
                 /* Now we set local_using_sysemu to be used for one loop */
                 local_using_sysemu = get_using_sysemu();
@@ -320,7 +322,10 @@ void userspace(struct uml_pt_regs *regs)
                               errno);
 
                 regs->is_user = 1;
-                save_registers(pid, regs);
+                if (ptrace(PTRACE_GETREGS, pid, 0, regs->gp))
+                        panic("userspace - saving registers failed, "
+                              "errno = %d\n", errno);
+
                 UPT_SYSCALL_NR(regs) = -1; /* Assume: It's not a syscall */
 
                 if (WIFSTOPPED(status)) {
@@ -343,7 +348,7 @@ void userspace(struct uml_pt_regs *regs)
                                 break;
                         case SIGVTALRM:
                                 now = os_nsecs();
-                                if(now < nsecs)
+                                if (now < nsecs)
                                         break;
                                 block_signals();
                                 (*sig_info[sig])(sig, regs);