[SPARC64]: Simplify user fault fixup handling.

Instead of doing byte-at-a-time user accesses to figure
out where the fault occurred, read the saved fault_address
from the current thread structure.

For the sake of defensive programming, if the fault_address
does not fall into the user buffer range, simply assume the
whole area faulted.  This will cause the fixup for
copy_from_user() to clear the entire kernel side buffer.

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

1 files changed, 3 insertions, 3 deletions

diff --git a/include/asm-sparc64/uaccess.h b/include/asm-sparc64/uaccess.h
index bc8ddbb1cbed..203e8eee6351 100644
--- a/include/asm-sparc64/uaccess.h
+++ b/include/asm-sparc64/uaccess.h
@@ -251,7 +251,7 @@ copy_from_user(void *to, const void __user *from, unsigned long size)
 {
         unsigned long ret = ___copy_from_user(to, from, size);
 
-        if (ret)
+        if (unlikely(ret))
                 ret = copy_from_user_fixup(to, from, size);
         return ret;
 }
@@ -267,7 +267,7 @@ copy_to_user(void __user *to, const void *from, unsigned long size)
 {
         unsigned long ret = ___copy_to_user(to, from, size);
 
-        if (ret)
+        if (unlikely(ret))
                 ret = copy_to_user_fixup(to, from, size);
         return ret;
 }
@@ -283,7 +283,7 @@ copy_in_user(void __user *to, void __user *from, unsigned long size)
 {
         unsigned long ret = ___copy_in_user(to, from, size);
 
-        if (ret)
+        if (unlikely(ret))
                 ret = copy_in_user_fixup(to, from, size);
         return ret;
 }