[PATCH 04/13] SPARC64: Fix missing fold at end of checksums.

Chris Wright
2006-06-20T11:49:41Z

[-- Attachment #1: sparc64-fix-missing-fold-at-end-of-checksums.patch --]
[-- Type: text/plain, Size: 1508 bytes --]

-stable review patch. If anyone has any objections, please let us know.
------------------

From: David Miller <davem@davemloft.net>

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>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---

arch/sparc64/lib/checksum.S | 5 +++--
arch/sparc64/lib/csum_copy.S | 5 +++--
2 files changed, 6 insertions(+), 4 deletions(-)

--- linux-2.6.16.21.orig/arch/sparc64/lib/checksum.S
+++ linux-2.6.16.21/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
--- linux-2.6.16.21.orig/arch/sparc64/lib/csum_copy.S
+++ linux-2.6.16.21/arch/sparc64/lib/csum_copy.S
@@ -221,11 +221,12 @@ FUNC_NAME: /* %o0=src, %o1=dst, %o2=len
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

--