Merge remote-tracking branch 'master' into queue

Merge reason: development work has dependency on kvm patches merged
upstream.

Conflicts:
	arch/powerpc/include/asm/Kbuild
	arch/powerpc/include/asm/kvm_para.h

Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

1 files changed, 45 insertions, 110 deletions

diff --git a/arch/alpha/kernel/entry.S b/arch/alpha/kernel/entry.S
index ec0da0567ab..a7607832dd4 100644
--- a/arch/alpha/kernel/entry.S
+++ b/arch/alpha/kernel/entry.S
@@ -311,7 +311,7 @@ entSys:
 
 	.align	4
 ret_from_sys_call:
-	cmovne	$26, 0, $19		/* $19 = 0 => non-restartable */
+	cmovne	$26, 0, $18		/* $18 = 0 => non-restartable */
 	ldq	$0, SP_OFF($sp)
 	and	$0, 8, $0
 	beq	$0, ret_to_kernel
@@ -320,8 +320,8 @@ ret_to_user:
 		sampling and the rti.  */
 	lda	$16, 7
 	call_pal PAL_swpipl
-	ldl	$5, TI_FLAGS($8)
-	and	$5, _TIF_WORK_MASK, $2
+	ldl	$17, TI_FLAGS($8)
+	and	$17, _TIF_WORK_MASK, $2
 	bne	$2, work_pending
 restore_all:
 	RESTORE_ALL
@@ -341,10 +341,10 @@ $syscall_error:
 	 * frame to indicate that a negative return value wasn't an
 	 * error number..
 	 */
-	ldq	$19, 0($sp)	/* old syscall nr (zero if success) */
-	beq	$19, $ret_success
+	ldq	$18, 0($sp)	/* old syscall nr (zero if success) */
+	beq	$18, $ret_success
 
-	ldq	$20, 72($sp)	/* .. and this a3 */
+	ldq	$19, 72($sp)	/* .. and this a3 */
 	subq	$31, $0, $0	/* with error in v0 */
 	addq	$31, 1, $1	/* set a3 for errno return */
 	stq	$0, 0($sp)
@@ -362,51 +362,35 @@ $ret_success:
  * Do all cleanup when returning from all interrupts and system calls.
  *
  * Arguments:
- *       $5: TI_FLAGS.
  *       $8: current.
- *      $19: The old syscall number, or zero if this is not a return
+ *      $17: TI_FLAGS.
+ *      $18: The old syscall number, or zero if this is not a return
  *           from a syscall that errored and is possibly restartable.
- *      $20: The old a3 value
+ *      $19: The old a3 value
  */
 
 	.align	4
 	.ent	work_pending
 work_pending:
-	and	$5, _TIF_NEED_RESCHED, $2
-	beq	$2, $work_notifysig
+	and	$17, _TIF_NOTIFY_RESUME | _TIF_SIGPENDING, $2
+	bne	$2, $work_notifysig
 
 $work_resched:
-	subq	$sp, 16, $sp
-	stq	$19, 0($sp)              /* save syscall nr */
-	stq	$20, 8($sp)              /* and error indication (a3) */
+	/*
+	 * We can get here only if we returned from syscall without SIGPENDING
+	 * or got through work_notifysig already.  Either case means no syscall
+	 * restarts for us, so let $18 and $19 burn.
+	 */
 	jsr	$26, schedule
-	ldq	$19, 0($sp)
-	ldq	$20, 8($sp)
-	addq	$sp, 16, $sp
-	/* Make sure need_resched and sigpending don't change between
-		sampling and the rti.  */
-	lda	$16, 7
-	call_pal PAL_swpipl
-	ldl	$5, TI_FLAGS($8)
-	and	$5, _TIF_WORK_MASK, $2
-	beq	$2, restore_all
-	and	$5, _TIF_NEED_RESCHED, $2
-	bne	$2, $work_resched
+	mov	0, $18
+	br	ret_to_user
 
 $work_notifysig:
 	mov	$sp, $16
 	bsr	$1, do_switch_stack
-	mov	$sp, $17
-	mov	$5, $18
-	mov	$19, $9		/* save old syscall number */
-	mov	$20, $10	/* save old a3 */
-	and	$5, _TIF_SIGPENDING, $2
-	cmovne	$2, 0, $9	/* we don't want double syscall restarts */
-	jsr	$26, do_notify_resume
-	mov	$9, $19
-	mov	$10, $20
+	jsr	$26, do_work_pending
 	bsr	$1, undo_switch_stack
-	br	ret_to_user
+	br	restore_all
 .end work_pending
 
 /*
@@ -418,11 +402,10 @@ $work_notifysig:
 strace:
 	/* set up signal stack, call syscall_trace */
 	bsr	$1, do_switch_stack
-	jsr	$26, syscall_trace
+	jsr	$26, syscall_trace_enter /* returns the syscall number */
 	bsr	$1, undo_switch_stack
 
-	/* get the system call number and the arguments back.. */
-	ldq	$0, 0($sp)
+	/* get the arguments back.. */
 	ldq	$16, SP_OFF+24($sp)
 	ldq	$17, SP_OFF+32($sp)
 	ldq	$18, SP_OFF+40($sp)
@@ -449,15 +432,15 @@ $strace_success:
 	stq	$0, 0($sp)		/* save return value */
 
 	bsr	$1, do_switch_stack
-	jsr	$26, syscall_trace
+	jsr	$26, syscall_trace_leave
 	bsr	$1, undo_switch_stack
 	br	$31, ret_from_sys_call
 
 	.align	3
 $strace_error:
-	ldq	$19, 0($sp)	/* old syscall nr (zero if success) */
-	beq	$19, $strace_success
-	ldq	$20, 72($sp)	/* .. and this a3 */
+	ldq	$18, 0($sp)	/* old syscall nr (zero if success) */
+	beq	$18, $strace_success
+	ldq	$19, 72($sp)	/* .. and this a3 */
 
 	subq	$31, $0, $0	/* with error in v0 */
 	addq	$31, 1, $1	/* set a3 for errno return */
@@ -465,11 +448,11 @@ $strace_error:
 	stq	$1, 72($sp)	/* a3 for return */
 
 	bsr	$1, do_switch_stack
-	mov	$19, $9		/* save old syscall number */
-	mov	$20, $10	/* save old a3 */
-	jsr	$26, syscall_trace
-	mov	$9, $19
-	mov	$10, $20
+	mov	$18, $9		/* save old syscall number */
+	mov	$19, $10	/* save old a3 */
+	jsr	$26, syscall_trace_leave
+	mov	$9, $18
+	mov	$10, $19
 	bsr	$1, undo_switch_stack
 
 	mov	$31, $26	/* tell "ret_from_sys_call" we can restart */
@@ -609,59 +592,20 @@ ret_from_fork:
 .end ret_from_fork
 
 /*
- * kernel_thread(fn, arg, clone_flags)
+ * ... and new kernel threads - here
  */
 	.align 4
-	.globl	kernel_thread
-	.ent	kernel_thread
-kernel_thread:
-	/* We can be called from a module.  */
-	ldgp	$gp, 0($27)
-	.prologue 1
-	subq	$sp, SP_OFF+6*8, $sp
-	br	$1, 2f		/* load start address */
-
-	/* We've now "returned" from a fake system call.  */
-	unop
-	blt	$0, 1f		/* error?  */
-	ldi	$1, 0x3fff
-	beq	$20, 1f		/* parent or child?  */
-
-	bic	$sp, $1, $8	/* in child.  */
-	jsr	$26, ($27)
-	ldgp	$gp, 0($26)
-	mov	$0, $16
-	mov	$31, $26
-	jmp	$31, sys_exit
-
-1:	ret			/* in parent.  */
-
-	.align 4
-2:	/* Fake a system call stack frame, as we can't do system calls
-	   from kernel space.  Note that we store FN and ARG as they
-	   need to be set up in the child for the call.  Also store $8
-	   and $26 for use in the parent.  */
-	stq	$31, SP_OFF($sp)	/* ps */
-	stq	$1, SP_OFF+8($sp)	/* pc */
-	stq	$gp, SP_OFF+16($sp)	/* gp */
-	stq	$16, 136($sp)		/* $27; FN for child */
-	stq	$17, SP_OFF+24($sp)	/* $16; ARG for child */
-	stq	$8, 64($sp)		/* $8 */
-	stq	$26, 128($sp)		/* $26 */
-	/* Avoid the HAE being gratuitously wrong, to avoid restoring it.  */
-	ldq	$2, alpha_mv+HAE_CACHE
-	stq	$2, 152($sp)		/* HAE */
-
-	/* Shuffle FLAGS to the front; add CLONE_VM.  */
-	ldi	$1, CLONE_VM|CLONE_UNTRACED
-	or	$18, $1, $16
-	bsr	$26, sys_clone
-
-	/* We don't actually care for a3 success widgetry in the kernel.
-	   Not for positive errno values.  */
-	stq	$0, 0($sp)		/* $0 */
-	br	ret_to_kernel
-.end kernel_thread
+	.globl	ret_from_kernel_thread
+	.ent	ret_from_kernel_thread
+ret_from_kernel_thread:
+	mov	$17, $16
+	jsr	$26, schedule_tail
+	mov	$9, $27
+	mov	$10, $16
+	jsr	$26, ($9)
+	mov	$31, $19		/* to disable syscall restarts */
+	br	$31, ret_to_user
+.end ret_from_kernel_thread
 
 
 /*
@@ -722,7 +666,7 @@ sys_sigreturn:
 	lda	$sp, -SWITCH_STACK_SIZE($sp)
 	jsr	$26, do_sigreturn
 	bne	$9, 1f
-	jsr	$26, syscall_trace
+	jsr	$26, syscall_trace_leave
 1:	br	$1, undo_switch_stack
 	br	ret_from_sys_call
 .end sys_sigreturn
@@ -739,21 +683,12 @@ sys_rt_sigreturn:
 	lda	$sp, -SWITCH_STACK_SIZE($sp)
 	jsr	$26, do_rt_sigreturn
 	bne	$9, 1f
-	jsr	$26, syscall_trace
+	jsr	$26, syscall_trace_leave
 1:	br	$1, undo_switch_stack
 	br	ret_from_sys_call
 .end sys_rt_sigreturn
 
 	.align	4
-	.globl	sys_execve
-	.ent	sys_execve
-sys_execve:
-	.prologue 0
-	mov	$sp, $19
-	jmp	$31, do_sys_execve
-.end sys_execve
-
-	.align	4
 	.globl	alpha_ni_syscall
 	.ent	alpha_ni_syscall
 alpha_ni_syscall: