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-rw-r--r--arch/powerpc/lib/checksum_wrappers.c102
1 files changed, 102 insertions, 0 deletions
diff --git a/arch/powerpc/lib/checksum_wrappers.c b/arch/powerpc/lib/checksum_wrappers.c
new file mode 100644
index 000000000000..08e3a3356c40
--- /dev/null
+++ b/arch/powerpc/lib/checksum_wrappers.c
@@ -0,0 +1,102 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ * Copyright (C) IBM Corporation, 2010
+ *
+ * Author: Anton Blanchard <anton@au.ibm.com>
+ */
+#include <linux/export.h>
+#include <linux/compiler.h>
+#include <linux/types.h>
+#include <asm/checksum.h>
+#include <asm/uaccess.h>
+
+__wsum csum_and_copy_from_user(const void __user *src, void *dst,
+ int len, __wsum sum, int *err_ptr)
+{
+ unsigned int csum;
+
+ might_sleep();
+
+ *err_ptr = 0;
+
+ if (!len) {
+ csum = 0;
+ goto out;
+ }
+
+ if (unlikely((len < 0) || !access_ok(VERIFY_READ, src, len))) {
+ *err_ptr = -EFAULT;
+ csum = (__force unsigned int)sum;
+ goto out;
+ }
+
+ csum = csum_partial_copy_generic((void __force *)src, dst,
+ len, sum, err_ptr, NULL);
+
+ if (unlikely(*err_ptr)) {
+ int missing = __copy_from_user(dst, src, len);
+
+ if (missing) {
+ memset(dst + len - missing, 0, missing);
+ *err_ptr = -EFAULT;
+ } else {
+ *err_ptr = 0;
+ }
+
+ csum = csum_partial(dst, len, sum);
+ }
+
+out:
+ return (__force __wsum)csum;
+}
+EXPORT_SYMBOL(csum_and_copy_from_user);
+
+__wsum csum_and_copy_to_user(const void *src, void __user *dst, int len,
+ __wsum sum, int *err_ptr)
+{
+ unsigned int csum;
+
+ might_sleep();
+
+ *err_ptr = 0;
+
+ if (!len) {
+ csum = 0;
+ goto out;
+ }
+
+ if (unlikely((len < 0) || !access_ok(VERIFY_WRITE, dst, len))) {
+ *err_ptr = -EFAULT;
+ csum = -1; /* invalid checksum */
+ goto out;
+ }
+
+ csum = csum_partial_copy_generic(src, (void __force *)dst,
+ len, sum, NULL, err_ptr);
+
+ if (unlikely(*err_ptr)) {
+ csum = csum_partial(src, len, sum);
+
+ if (copy_to_user(dst, src, len)) {
+ *err_ptr = -EFAULT;
+ csum = -1; /* invalid checksum */
+ }
+ }
+
+out:
+ return (__force __wsum)csum;
+}
+EXPORT_SYMBOL(csum_and_copy_to_user);