go a bit further with miods last change to copy{in,out}{,str} and

stash the address of the user structure to avoid having to always
follow two pointers to get to the address of the onfault handler.
this lets the code shrink and avoids some register use.

while here, move the range checking of the arguments before saving
the callers args onto the stack so we can ret faster on error.

ok miod@

1 files changed, 38 insertions, 68 deletions

diff --git a/sys/arch/alpha/alpha/locore.s b/sys/arch/alpha/alpha/locore.s
index 8505a39957f..86d893c30fb 100644
--- a/sys/arch/alpha/alpha/locore.s
+++ b/sys/arch/alpha/alpha/locore.s
@@ -1,4 +1,4 @@
-/* $OpenBSD: locore.s,v 1.42 2015/06/23 19:49:41 miod Exp $ */
+/* $OpenBSD: locore.s,v 1.43 2015/07/20 07:45:23 dlg Exp $ */
 /* $NetBSD: locore.s,v 1.94 2001/04/26 03:10:44 ross Exp $ */
 
 /*-
@@ -887,25 +887,20 @@ LEAF(copystr, 4)
 
 NESTED(copyinstr, 4, 16, ra, IM_RA|IM_S0, 0)
 	LDGP(pv)
+	ldiq	t0, VM_MAX_ADDRESS		/* make sure that src addr   */
+	cmpult	a0, t0, t1			/* is in user space.	     */
+	beq	t1, copyfault			/* if it's not, error out.   */
 	lda	sp, -16(sp)			/* set up stack frame	     */
 	stq	ra, (16-8)(sp)			/* save ra		     */
 	stq	s0, (16-16)(sp)			/* save s0		     */
 	/* Note: GET_CURPROC clobbers v0, t0, t8...t11. */
 	GET_CURPROC
-	ldq	s0, 0(v0)
-	ldiq	t0, VM_MAX_ADDRESS		/* make sure that src addr   */
-	cmpult	a0, t0, t1			/* is in user space.	     */
-	beq	t1, copyerr			/* if it's not, error out.   */
+	ldq	t0, 0(v0)
+	ldq	s0, P_ADDR(t0)
 	lda	v0, copyerr			/* set up fault handler.     */
-	.set noat
-	ldq	at_reg, P_ADDR(s0)
-	stq	v0, U_PCB_ONFAULT(at_reg)
-	.set at
+	stq	v0, U_PCB_ONFAULT(s0)
 	CALL(copystr)				/* do the copy.		     */
-	.set noat
-	ldq	at_reg, P_ADDR(s0)
-	stq	zero, U_PCB_ONFAULT(at_reg)
-	.set at
+	stq	zero, U_PCB_ONFAULT(s0)		/* kill the fault handler.   */
 	ldq	ra, (16-8)(sp)			/* restore ra.		     */
 	ldq	s0, (16-16)(sp)			/* restore s0.		     */
 	lda	sp, 16(sp)			/* kill stack frame.	     */
@@ -914,25 +909,20 @@ NESTED(copyinstr, 4, 16, ra, IM_RA|IM_S0, 0)
 
 NESTED(copyoutstr, 4, 16, ra, IM_RA|IM_S0, 0)
 	LDGP(pv)
+	ldiq	t0, VM_MAX_ADDRESS		/* make sure that dest addr  */
+	cmpult	a1, t0, t1			/* is in user space.	     */
+	beq	t1, copyfault			/* if it's not, error out.   */
 	lda	sp, -16(sp)			/* set up stack frame	     */
 	stq	ra, (16-8)(sp)			/* save ra		     */
 	stq	s0, (16-16)(sp)			/* save s0		     */
 	/* Note: GET_CURPROC clobbers v0, t0, t8...t11. */
 	GET_CURPROC
-	ldq	s0, 0(v0)
-	ldiq	t0, VM_MAX_ADDRESS		/* make sure that dest addr  */
-	cmpult	a1, t0, t1			/* is in user space.	     */
-	beq	t1, copyerr			/* if it's not, error out.   */
+	ldq	t0, 0(v0)
+	ldq	s0, P_ADDR(t0)
 	lda	v0, copyerr			/* set up fault handler.     */
-	.set noat
-	ldq	at_reg, P_ADDR(s0)
-	stq	v0, U_PCB_ONFAULT(at_reg)
-	.set at
+	stq	v0, U_PCB_ONFAULT(s0)
 	CALL(copystr)				/* do the copy.		     */
-	.set noat
-	ldq	at_reg, P_ADDR(s0)		/* kill the fault handler.   */
-	stq	zero, U_PCB_ONFAULT(at_reg)
-	.set at
+	stq	zero, U_PCB_ONFAULT(s0)		/* kill the fault handler.   */
 	ldq	ra, (16-8)(sp)			/* restore ra.		     */
 	ldq	s0, (16-16)(sp)			/* restore s0.		     */
 	lda	sp, 16(sp)			/* kill stack frame.	     */
@@ -957,18 +947,13 @@ NESTED(kcopy, 3, 32, ra, IM_RA|IM_S0|IM_S1, 0)
 	stq	s1, (32-24)(sp)			/* save s1		     */
 	/* Note: GET_CURPROC clobbers v0, t0, t8...t11. */
 	GET_CURPROC
-	ldq	s1, 0(v0)
+	ldq	t0, 0(v0)
+	ldq	s1, P_ADDR(t0)
 	lda	v0, kcopyerr			/* set up fault handler.     */
-	.set noat
-	ldq	at_reg, P_ADDR(s1)
-	ldq	s0, U_PCB_ONFAULT(at_reg)	/* save old handler.	     */
-	stq	v0, U_PCB_ONFAULT(at_reg)
-	.set at
+	ldq	s0, U_PCB_ONFAULT(s1)		/* save old handler.	     */
+	stq	v0, U_PCB_ONFAULT(s1)
 	CALL(bcopy)				/* do the copy.		     */
-	.set noat
-	ldq	at_reg, P_ADDR(s1)		/* restore the old handler.  */
-	stq	s0, U_PCB_ONFAULT(at_reg)
-	.set at
+	stq	s0, U_PCB_ONFAULT(s1)
 	ldq	ra, (32-8)(sp)			/* restore ra.		     */
 	ldq	s0, (32-16)(sp)			/* restore s0.		     */
 	ldq	s1, (32-24)(sp)			/* restore s1.		     */
@@ -978,11 +963,7 @@ NESTED(kcopy, 3, 32, ra, IM_RA|IM_S0|IM_S1, 0)
 	END(kcopy)
 
 LEAF(kcopyerr, 0)
-	LDGP(pv)
-	.set noat
-	ldq	at_reg, P_ADDR(s1)		/* restore the old handler.  */
-	stq	s0, U_PCB_ONFAULT(at_reg)
-	.set at
+	stq	s0, U_PCB_ONFAULT(s1)		/* restore the old handler.  */
 	ldq	ra, (32-8)(sp)			/* restore ra.		     */
 	ldq	s0, (32-16)(sp)			/* restore s0.		     */
 	ldq	s1, (32-24)(sp)			/* restore s1.		     */
@@ -993,25 +974,20 @@ END(kcopyerr)
 
 NESTED(copyin, 3, 16, ra, IM_RA|IM_S0, 0)
 	LDGP(pv)
+	ldiq	t0, VM_MAX_ADDRESS		/* make sure that src addr   */
+	cmpult	a0, t0, t1			/* is in user space.	     */
+	beq	t1, copyfault			/* if it's not, error out.   */
 	lda	sp, -16(sp)			/* set up stack frame	     */
 	stq	ra, (16-8)(sp)			/* save ra		     */
 	stq	s0, (16-16)(sp)			/* save s0		     */
 	/* Note: GET_CURPROC clobbers v0, t0, t8...t11. */
 	GET_CURPROC
-	ldq	s0, 0(v0)
-	ldiq	t0, VM_MAX_ADDRESS		/* make sure that src addr   */
-	cmpult	a0, t0, t1			/* is in user space.	     */
-	beq	t1, copyerr			/* if it's not, error out.   */
+	ldq	t0, 0(v0)
+	ldq	s0, P_ADDR(t0)
 	lda	v0, copyerr			/* set up fault handler.     */
-	.set noat
-	ldq	at_reg, P_ADDR(s0)
-	stq	v0, U_PCB_ONFAULT(at_reg)
-	.set at
+	stq	v0, U_PCB_ONFAULT(s0)
 	CALL(bcopy)				/* do the copy.		     */
-	.set noat
-	ldq	at_reg, P_ADDR(s0)		/* kill the fault handler.   */
-	stq	zero, U_PCB_ONFAULT(at_reg)
-	.set at
+	stq	zero, U_PCB_ONFAULT(s0)		/* kill the fault handler.   */
 	ldq	ra, (16-8)(sp)			/* restore ra.		     */
 	ldq	s0, (16-16)(sp)			/* restore s0.		     */
 	lda	sp, 16(sp)			/* kill stack frame.	     */
@@ -1021,25 +997,21 @@ NESTED(copyin, 3, 16, ra, IM_RA|IM_S0, 0)
 
 NESTED(copyout, 3, 16, ra, IM_RA|IM_S0, 0)
 	LDGP(pv)
+	ldiq	t0, VM_MAX_ADDRESS		/* make sure that dest addr  */
+	cmpult	a1, t0, t1			/* is in user space.	     */
+	beq	t1, copyfault			/* if it's not, error out.   */
 	lda	sp, -16(sp)			/* set up stack frame	     */
 	stq	ra, (16-8)(sp)			/* save ra		     */
 	stq	s0, (16-16)(sp)			/* save s0		     */
 	/* Note: GET_CURPROC clobbers v0, t0, t8...t11. */
 	GET_CURPROC
-	ldq	s0, 0(v0)
-	ldiq	t0, VM_MAX_ADDRESS		/* make sure that dest addr  */
-	cmpult	a1, t0, t1			/* is in user space.	     */
-	beq	t1, copyerr			/* if it's not, error out.   */
+	GET_CURPROC
+	ldq	t0, 0(v0)
+	ldq	s0, P_ADDR(t0)
 	lda	v0, copyerr			/* set up fault handler.     */
-	.set noat
-	ldq	at_reg, P_ADDR(s0)
-	stq	v0, U_PCB_ONFAULT(at_reg)
-	.set at
+	stq	v0, U_PCB_ONFAULT(s0)
 	CALL(bcopy)				/* do the copy.		     */
-	.set noat
-	ldq	at_reg, P_ADDR(s0)		/* kill the fault handler.   */
-	stq	zero, U_PCB_ONFAULT(at_reg)
-	.set at
+	stq	zero, U_PCB_ONFAULT(s0)		/* kill the fault handler.   */
 	ldq	ra, (16-8)(sp)			/* restore ra.		     */
 	ldq	s0, (16-16)(sp)			/* restore s0.		     */
 	lda	sp, 16(sp)			/* kill stack frame.	     */
@@ -1049,13 +1021,11 @@ NESTED(copyout, 3, 16, ra, IM_RA|IM_S0, 0)
 
 LEAF(copyerr, 0)
 	LDGP(pv)
-	.set noat
-	ldq	at_reg, P_ADDR(s0)		/* kill the fault handler.   */
-	stq	zero, U_PCB_ONFAULT(at_reg)
-	.set at
+	stq	zero, U_PCB_ONFAULT(s0)		/* kill the fault handler.   */
 	ldq	ra, (16-8)(sp)			/* restore ra.		     */
 	ldq	s0, (16-16)(sp)			/* restore s0.		     */
 	lda	sp, 16(sp)			/* kill stack frame.	     */
+copyfault:
 	ldiq	v0, EFAULT			/* return EFAULT.	     */
 	RET
 END(copyerr)