patch-2.4.21 linux-2.4.21/arch/s390x/lib/uaccess.S

• Lines: 128
• Date: 2003-06-13 07:51:32.000000000 -0700
• Orig file: linux-2.4.20/arch/s390x/lib/uaccess.S
• Orig date: 2002-02-25 11:37:56.000000000 -0800

diff -urN linux-2.4.20/arch/s390x/lib/uaccess.S linux-2.4.21/arch/s390x/lib/uaccess.S
@@ -1,9 +1,9 @@
 /*
  *  arch/s390x/lib/uaccess.S
- *    fixup routines for copy_{from|to}_user functions.
+ *    __copy_{from|to}_user functions.
  *
- *  S390
- *    Copyright (C) 2000 IBM Deutschland Entwicklung GmbH, IBM Corporation
+ *  s390
+ *    Copyright (C) 2000,2002 IBM Deutschland Entwicklung GmbH, IBM Corporation
  *    Authors(s): Martin Schwidefsky (schwidefsky@de.ibm.com)
  *
  *  These functions have standard call interface
@@ -19,20 +19,26 @@
 	sacf	512
 0:	mvcle	%r2,%r4,0
 	jo	0b
-	sacf	0
+1:	sacf	0
 	lgr	%r2,%r5
 	br	%r14
-1:	lg	%r1,__LC_PGM_OLD_PSW+8
-2:	lghi	%r3,-4096
-        ng	%r3,__LC_TRANS_EXC_ADDR
-        sgr	%r3,%r4
-        bm	4(%r1)
-3:      mvcle	%r2,%r4,0
-        b	4(%r1)
+2:	lghi	%r1,-4096
+	lgr	%r3,%r4
+	slgr	%r3,%r1      # %r3 = %r4 + 4096
+	ngr	%r3,%r1      # %r3 = (%r4 + 4096) & -4096
+	slgr	%r3,%r4      # %r3 = #bytes to next user page boundary
+	clgr	%r5,%r3      # copy crosses next page boundary ?
+	jnh	1b           # no, this page fauled
+	# The page after the current user page might have faulted.
+	# We cant't find out which page because the program check handler
+	# might have callled schedule, destroying all lowcore information.
+	# We retry with the shortened length.
+3:	mvcle	%r2,%r4,0
+	jo	3b
+	j	1b
         .section __ex_table,"a"
-        .align	8
-	.quad	0b,1b
-	.quad	3b,2b
+	.quad	0b,2b
+	.quad	3b,1b
         .previous
 
         .align 4
@@ -43,20 +49,26 @@
 	sacf	512
 0:	mvcle	%r4,%r2,0
 	jo	0b
-	sacf	0
+1:	sacf	0
 	lgr	%r2,%r3
 	br	%r14
-1:	lg	%r1,__LC_PGM_OLD_PSW+8
-2:      lghi	%r5,-4096
-        ng	%r5,__LC_TRANS_EXC_ADDR
-        sgr	%r5,%r4
-        bm	4(%r1)
-3:      mvcle	%r4,%r2,0
-        b	4(%r1)
+2:	lghi	%r1,-4096
+	lgr	%r5,%r4
+	slgr	%r5,%r1      # %r5 = %r4 + 4096
+	ngr	%r5,%r1      # %r5 = (%r4 + 4096) & -4096
+	slgr	%r5,%r4      # %r5 = #bytes to next user page boundary
+	clgr	%r3,%r5      # copy crosses next page boundary ?
+	jnh	1b           # no, the current page fauled
+	# The page after the current user page might have faulted.
+	# We cant't find out which page because the program check handler
+	# might have callled schedule, destroying all lowcore information.
+	# We retry with the shortened length.
+3:	mvcle	%r4,%r2,0
+	jo	3b
+	j	1b
         .section __ex_table,"a"
-        .align	8
-        .quad	0b,1b
-        .quad	3b,2b
+	.quad	0b,2b
+	.quad	3b,1b
         .previous
 
         .align 4
@@ -70,18 +82,26 @@
 	sacf	512
 0:	mvcle	%r4,%r2,0
 	jo	0b
-	sacf	0
-	lgr	%r2,%r5
+1:	sacf	0
 	br	%r14
-1:	lg	%r1,__LC_PGM_OLD_PSW+8
-2:      lghi	%r5,-4096
-        ng	%r5,__LC_TRANS_EXC_ADDR
-        sgr	%r5,%r4
-        bm	4(%r1)
-3:      mvcle	%r4,%r2,0
-        b	4(%r1)
+2:	lgr	%r2,%r5
+	lghi	%r1,-4096
+	slgr	%r5,%r1      # %r5 = %r4 + 4096
+	ngr	%r5,%r1      # %r5 = (%r4 + 4096) & -4096
+	slgr	%r5,%r4      # %r5 = #bytes to next user page boundary
+	clgr	%r2,%r5      # copy crosses next page boundary ?
+	jnh	1b           # no, the current page fauled
+	# The page after the current user page might have faulted.
+	# We cant't find out which page because the program check handler
+	# might have callled schedule, destroying all lowcore information.
+	# We retry with the shortened length.
+	slgr	%r2,%r5
+3:	mvcle	%r4,%r2,0
+	jo	3b
+	j	1b
+4:	algr	%r2,%r5
+	j	1b
         .section __ex_table,"a"
-        .align	8
-        .quad	0b,1b
-        .quad	3b,2b
+	.quad	0b,2b
+        .quad	3b,4b
         .previous