[T106][ZXW-22]7520V3SCV2.01.01.02P42U09_VEC_V0.8_AP_VEC origin source commit
Change-Id: Ic6e05d89ecd62fc34f82b23dcf306c93764aec4b
diff --git a/ap/os/linux/linux-3.4.x/crypto/scatterwalk.c b/ap/os/linux/linux-3.4.x/crypto/scatterwalk.c
new file mode 100644
index 0000000..7281b8a
--- /dev/null
+++ b/ap/os/linux/linux-3.4.x/crypto/scatterwalk.c
@@ -0,0 +1,126 @@
+/*
+ * Cryptographic API.
+ *
+ * Cipher operations.
+ *
+ * Copyright (c) 2002 James Morris <jmorris@intercode.com.au>
+ * 2002 Adam J. Richter <adam@yggdrasil.com>
+ * 2004 Jean-Luc Cooke <jlcooke@certainkey.com>
+ *
+ * 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.
+ *
+ */
+
+#include <crypto/scatterwalk.h>
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/pagemap.h>
+#include <linux/highmem.h>
+#include <linux/scatterlist.h>
+
+static inline void memcpy_dir(void *buf, void *sgdata, size_t nbytes, int out)
+{
+ void *src = out ? buf : sgdata;
+ void *dst = out ? sgdata : buf;
+
+ memcpy(dst, src, nbytes);
+}
+
+void scatterwalk_start(struct scatter_walk *walk, struct scatterlist *sg)
+{
+ walk->sg = sg;
+
+ BUG_ON(!sg->length);
+
+ walk->offset = sg->offset;
+}
+EXPORT_SYMBOL_GPL(scatterwalk_start);
+
+void *scatterwalk_map(struct scatter_walk *walk)
+{
+ return kmap_atomic(scatterwalk_page(walk)) +
+ offset_in_page(walk->offset);
+}
+EXPORT_SYMBOL_GPL(scatterwalk_map);
+
+static void scatterwalk_pagedone(struct scatter_walk *walk, int out,
+ unsigned int more)
+{
+ if (out) {
+ struct page *page;
+
+ page = sg_page(walk->sg) + ((walk->offset - 1) >> PAGE_SHIFT);
+ if (!PageSlab(page))
+ flush_dcache_page(page);
+ }
+
+ if (more) {
+ walk->offset += PAGE_SIZE - 1;
+ walk->offset &= PAGE_MASK;
+ if (walk->offset >= walk->sg->offset + walk->sg->length)
+ scatterwalk_start(walk, scatterwalk_sg_next(walk->sg));
+ }
+}
+
+void scatterwalk_done(struct scatter_walk *walk, int out, int more)
+{
+ if (!(scatterwalk_pagelen(walk) & (PAGE_SIZE - 1)) || !more)
+ scatterwalk_pagedone(walk, out, more);
+}
+EXPORT_SYMBOL_GPL(scatterwalk_done);
+
+void scatterwalk_copychunks(void *buf, struct scatter_walk *walk,
+ size_t nbytes, int out)
+{
+ for (;;) {
+ unsigned int len_this_page = scatterwalk_pagelen(walk);
+ u8 *vaddr;
+
+ if (len_this_page > nbytes)
+ len_this_page = nbytes;
+
+ vaddr = scatterwalk_map(walk);
+ memcpy_dir(buf, vaddr, len_this_page, out);
+ scatterwalk_unmap(vaddr);
+
+ scatterwalk_advance(walk, len_this_page);
+
+ if (nbytes == len_this_page)
+ break;
+
+ buf += len_this_page;
+ nbytes -= len_this_page;
+
+ scatterwalk_pagedone(walk, out, 1);
+ }
+}
+EXPORT_SYMBOL_GPL(scatterwalk_copychunks);
+
+void scatterwalk_map_and_copy(void *buf, struct scatterlist *sg,
+ unsigned int start, unsigned int nbytes, int out)
+{
+ struct scatter_walk walk;
+ unsigned int offset = 0;
+
+ if (!nbytes)
+ return;
+
+ for (;;) {
+ scatterwalk_start(&walk, sg);
+
+ if (start < offset + sg->length)
+ break;
+
+ offset += sg->length;
+ sg = scatterwalk_sg_next(sg);
+ }
+
+ scatterwalk_advance(&walk, start - offset);
+ scatterwalk_copychunks(buf, &walk, nbytes, out);
+ scatterwalk_done(&walk, out, 0);
+}
+EXPORT_SYMBOL_GPL(scatterwalk_map_and_copy);