alpha: switch to generic fork/vfork/clone

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

arch/alpha/include/asm/unistd.h

@@ -482,6 +482,9 @@
 #define __ARCH_WANT_SYS_SIGPENDING
 #define __ARCH_WANT_SYS_RT_SIGSUSPEND
 #define __ARCH_WANT_SYS_EXECVE
+#define __ARCH_WANT_SYS_FORK
+#define __ARCH_WANT_SYS_VFORK
+#define __ARCH_WANT_SYS_CLONE
 
 /* "Conditional" syscalls.  What we want is
 

arch/alpha/kernel/entry.S

@@ -612,44 +612,24 @@ ret_from_kernel_thread:
  * Special system calls.  Most of these are special in that they either
  * have to play switch_stack games or in some way use the pt_regs struct.
  */
+
+.macro	fork_like name
 	.align	4
-	.globl	sys_fork
-	.ent	sys_fork
-sys_fork:
+	.globl	alpha_\name
+	.ent	alpha_\name
+alpha_\name:
 	.prologue 0
 	bsr	$1, do_switch_stack
-	bis	$31, SIGCHLD, $16
-	mov	$31, $17
-	mov	$31, $18
-	mov	$31, $19
-	mov	$31, $20
-	jsr	$26, alpha_clone
-fork_out:
+	jsr	$26, sys_\name
 	ldq	$26, 56($sp)
 	lda	$sp, SWITCH_STACK_SIZE($sp)
 	ret
-.end sys_fork
+.end	alpha_\name
+.endm
 
-	.align	4
-	.globl	sys_clone
-	.ent	sys_clone
-sys_clone:
-	.prologue 0
-	bsr	$1, do_switch_stack
-	/* $16, $17, $18, $19, $20 come from the user.  */
-	lda	$26, fork_out
-	jsr	$31, alpha_clone
-.end sys_clone
-
-	.align	4
-	.globl	sys_vfork
-	.ent	sys_vfork
-sys_vfork:
-	.prologue 0
-	bsr	$1, do_switch_stack
-	lda	$26, fork_out
-	jsr	$31, alpha_vfork
-.end sys_vfork
+fork_like fork
+fork_like vfork
+fork_like clone
 
 	.align	4
 	.globl	sys_sigreturn

arch/alpha/kernel/process.c

@@ -234,31 +234,6 @@ release_thread(struct task_struct *dead_task)
 {
 }
 
-/*
- * "alpha_clone()".. By the time we get here, the
- * non-volatile registers have also been saved on the
- * stack. We do some ugly pointer stuff here.. (see
- * also copy_thread)
- *
- * Notice that "fork()" is implemented in terms of clone,
- * with parameters (SIGCHLD, 0).
- */
-int
-alpha_clone(unsigned long clone_flags, unsigned long usp,
-	    int __user *parent_tid, int __user *child_tid,
-	    unsigned long tls_value)
-{
-	return do_fork(clone_flags, usp, current_pt_regs(), 0,
-			parent_tid, child_tid);
-}
-
-int
-alpha_vfork(void)
-{
-	return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, 0,
-		       current_pt_regs(), 0, NULL, NULL);
-}
-
 /*
  * Copy an alpha thread..
  */

arch/alpha/kernel/systbls.S

@@ -12,7 +12,7 @@
 sys_call_table:
 	.quad alpha_ni_syscall			/* 0 */
 	.quad sys_exit
-	.quad sys_fork
+	.quad alpha_fork
 	.quad sys_read
 	.quad sys_write
 	.quad alpha_ni_syscall			/* 5 */
@@ -76,7 +76,7 @@ sys_call_table:
 	.quad sys_getpgrp
 	.quad sys_getpagesize
 	.quad alpha_ni_syscall			/* 65 */
-	.quad sys_vfork
+	.quad alpha_vfork
 	.quad sys_newstat
 	.quad sys_newlstat
 	.quad alpha_ni_syscall
@@ -330,7 +330,7 @@ sys_call_table:
 	.quad sys_ni_syscall			/* 309: old get_kernel_syms */
 	.quad sys_syslog			/* 310 */
 	.quad sys_reboot
-	.quad sys_clone
+	.quad alpha_clone
 	.quad sys_uselib
 	.quad sys_mlock
 	.quad sys_munlock			/* 315 */