[PATCH] ppc32: Fix __copy_tofrom_user return value
Recently the __copy_tofrom_user routine was modified to avoid doing
prefetches past the end of the source array. However, in doing so we
introduced a bug in that it now returns the wrong value for the number
of bytes not copied when a fault is encountered. This fixes it to
return the correct number.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/arch/ppc/lib/string.S b/arch/ppc/lib/string.S
index 8d08a2e..36c9b97 100644
--- a/arch/ppc/lib/string.S
+++ b/arch/ppc/lib/string.S
@@ -446,6 +446,7 @@
#ifdef CONFIG_8xx
/* Don't use prefetch on 8xx */
mtctr r0
+ li r0,0
53: COPY_16_BYTES_WITHEX(0)
bdnz 53b
@@ -564,7 +565,9 @@
/* or write fault in cacheline loop */
105: li r9,1
92: li r3,LG_CACHELINE_BYTES
- b 99f
+ mfctr r8
+ add r0,r0,r8
+ b 106f
/* read fault in final word loop */
108: li r9,0
b 93f
@@ -585,7 +588,7 @@
* r5 + (ctr << r3), and r9 is 0 for read or 1 for write.
*/
99: mfctr r0
- slw r3,r0,r3
+106: slw r3,r0,r3
add. r3,r3,r5
beq 120f /* shouldn't happen */
cmpwi 0,r9,0