Initial import

1 files changed, 105 insertions, 0 deletions

diff --git a/include/crypto/scatterwalk.h b/include/crypto/scatterwalk.h
new file mode 100644
index 000000000..20e4226a2
--- /dev/null
+++ b/include/crypto/scatterwalk.h
@@ -0,0 +1,105 @@
+/*
+ * Cryptographic scatter and gather helpers.
+ *
+ * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
+ * Copyright (c) 2002 Adam J. Richter <adam@yggdrasil.com>
+ * Copyright (c) 2004 Jean-Luc Cooke <jlcooke@certainkey.com>
+ * Copyright (c) 2007 Herbert Xu <herbert@gondor.apana.org.au>
+ *
+ * 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.
+ *
+ */
+
+#ifndef _CRYPTO_SCATTERWALK_H
+#define _CRYPTO_SCATTERWALK_H
+
+#include <asm/kmap_types.h>
+#include <crypto/algapi.h>
+#include <linux/hardirq.h>
+#include <linux/highmem.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/scatterlist.h>
+#include <linux/sched.h>
+
+static inline void scatterwalk_sg_chain(struct scatterlist *sg1, int num,
+					struct scatterlist *sg2)
+{
+	sg_set_page(&sg1[num - 1], (void *)sg2, 0, 0);
+	sg1[num - 1].page_link &= ~0x02;
+	sg1[num - 1].page_link |= 0x01;
+}
+
+static inline void scatterwalk_crypto_chain(struct scatterlist *head,
+					    struct scatterlist *sg,
+					    int chain, int num)
+{
+	if (chain) {
+		head->length += sg->length;
+		sg = sg_next(sg);
+	}
+
+	if (sg)
+		scatterwalk_sg_chain(head, num, sg);
+	else
+		sg_mark_end(head);
+}
+
+static inline unsigned long scatterwalk_samebuf(struct scatter_walk *walk_in,
+						struct scatter_walk *walk_out)
+{
+	return !(((sg_page(walk_in->sg) - sg_page(walk_out->sg)) << PAGE_SHIFT) +
+		 (int)(walk_in->offset - walk_out->offset));
+}
+
+static inline unsigned int scatterwalk_pagelen(struct scatter_walk *walk)
+{
+	unsigned int len = walk->sg->offset + walk->sg->length - walk->offset;
+	unsigned int len_this_page = offset_in_page(~walk->offset) + 1;
+	return len_this_page > len ? len : len_this_page;
+}
+
+static inline unsigned int scatterwalk_clamp(struct scatter_walk *walk,
+					     unsigned int nbytes)
+{
+	unsigned int len_this_page = scatterwalk_pagelen(walk);
+	return nbytes > len_this_page ? len_this_page : nbytes;
+}
+
+static inline void scatterwalk_advance(struct scatter_walk *walk,
+				       unsigned int nbytes)
+{
+	walk->offset += nbytes;
+}
+
+static inline unsigned int scatterwalk_aligned(struct scatter_walk *walk,
+					       unsigned int alignmask)
+{
+	return !(walk->offset & alignmask);
+}
+
+static inline struct page *scatterwalk_page(struct scatter_walk *walk)
+{
+	return sg_page(walk->sg) + (walk->offset >> PAGE_SHIFT);
+}
+
+static inline void scatterwalk_unmap(void *vaddr)
+{
+	kunmap_atomic(vaddr);
+}
+
+void scatterwalk_start(struct scatter_walk *walk, struct scatterlist *sg);
+void scatterwalk_copychunks(void *buf, struct scatter_walk *walk,
+			    size_t nbytes, int out);
+void *scatterwalk_map(struct scatter_walk *walk);
+void scatterwalk_done(struct scatter_walk *walk, int out, int more);
+
+void scatterwalk_map_and_copy(void *buf, struct scatterlist *sg,
+			      unsigned int start, unsigned int nbytes, int out);
+
+int scatterwalk_bytes_sglen(struct scatterlist *sg, int num_bytes);
+
+#endif  /* _CRYPTO_SCATTERWALK_H */