[SPARC64]: Fix missing fold at end of checksums.

Both csum_partial() and the csum_partial_copy*() family of routines
forget to do a final fold on the computed checksum value on sparc64.
So do the standard Sparc "add + set condition codes, add carry"
sequence, then make sure the high 32-bits of the return value are
clear.

Based upon some excellent detective work and debugging done by
Richard Braun and Samuel Thibault.

Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/arch/sparc64/lib/checksum.S b/arch/sparc64/lib/checksum.S
index ba9cd3c..1d230f6 100644 (file)
--- a/arch/sparc64/lib/checksum.S
+++ b/arch/sparc64/lib/checksum.S
@@ -165,8 +165,9 @@ csum_partial_end_cruft:
        sll             %g1, 8, %g1
        or              %o5, %g1, %o4
 
-1:     add             %o2, %o4, %o2
+1:     addcc           %o2, %o4, %o2
+       addc            %g0, %o2, %o2
 
 csum_partial_finish:
        retl
-        mov            %o2, %o0
+        srl            %o2, 0, %o0

diff --git a/arch/sparc64/lib/csum_copy.S b/arch/sparc64/lib/csum_copy.S
index 71af488..e566c77 100644 (file)
--- a/arch/sparc64/lib/csum_copy.S
+++ b/arch/sparc64/lib/csum_copy.S
@@ -221,11 +221,12 @@ FUNC_NAME:                /* %o0=src, %o1=dst, %o2=len, %o3=sum */
        sll             %g1, 8, %g1
        or              %o5, %g1, %o4
 
-1:     add             %o3, %o4, %o3
+1:     addcc           %o3, %o4, %o3
+       addc            %g0, %o3, %o3
 
 70:
        retl
-        mov            %o3, %o0
+        srl            %o3, 0, %o0
 
 95:    mov             0, GLOBAL_SPARE
        brlez,pn        %o2, 4f