aboutsummaryrefslogtreecommitdiff
path: root/drivers/staging/rtl8192su/ieee80211/scatterwalk.c
diff options
context:
space:
mode:
authorLinus Torvalds <torvalds@linux-foundation.org>2009-06-19 17:48:32 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2009-06-19 17:48:32 -0700
commitfb20871a54961b82d35303b43452928186c1361d (patch)
tree1beeb39e45eda1c8b5893090904b583fceeb07ef /drivers/staging/rtl8192su/ieee80211/scatterwalk.c
parentbee89ab228e6f51c4ddd3481b9bd491859a8ee7b (diff)
parentc7a5d70796379e3d51d0c652fbe1634b81d3bbd5 (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging-2.6: (342 commits) Staging: comedi: fix build errors Staging: udlfb: update to version 0.2.3 Staging: udlfb: fix some sparse warnings. Staging: udlfb: clean up checkpatch warnings in udlfb.c Staging: udlfb: clean up checkpatch warnings in udlfb.h Staging: udlfb: add udlfb driver to build Staging: add udlfb driver Staging: pata_rdc: remove pointless comments Staging: pata_rdc: remove DRIVER macros Staging: pata_rdc: remove dbgprintf macro Staging: pata_rdc: remove broken flag Staging: pata_rdc: fix build warnings Staging: pata_rdc: use PCI_DEVICE Staging: pata_rdc: remove function prototypes Staging: pata_rdc: coding style fixes Staging: pata_rdc: convert code to work in 2.6.29 Staging: pata_rdc: add driver to the build system Staging: add pata_rdc driver Staging: remove obsolete serqt_usb driver Staging: serqt_usb2 add the driver to the build ...
Diffstat (limited to 'drivers/staging/rtl8192su/ieee80211/scatterwalk.c')
-rw-r--r--drivers/staging/rtl8192su/ieee80211/scatterwalk.c126
1 files changed, 126 insertions, 0 deletions
diff --git a/drivers/staging/rtl8192su/ieee80211/scatterwalk.c b/drivers/staging/rtl8192su/ieee80211/scatterwalk.c
new file mode 100644
index 00000000000..49f401fbce8
--- /dev/null
+++ b/drivers/staging/rtl8192su/ieee80211/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 "kmap_types.h"
+
+#include <linux/kernel.h>
+#include <linux/mm.h>
+#include <linux/pagemap.h>
+#include <linux/highmem.h>
+#include <asm/scatterlist.h>
+#include "internal.h"
+#include "scatterwalk.h"
+
+enum km_type crypto_km_types[] = {
+ KM_USER0,
+ KM_USER1,
+ KM_SOFTIRQ0,
+ KM_SOFTIRQ1,
+};
+
+void *scatterwalk_whichbuf(struct scatter_walk *walk, unsigned int nbytes, void *scratch)
+{
+ if (nbytes <= walk->len_this_page &&
+ (((unsigned long)walk->data) & (PAGE_CACHE_SIZE - 1)) + nbytes <=
+ PAGE_CACHE_SIZE)
+ return walk->data;
+ else
+ return scratch;
+}
+
+static void memcpy_dir(void *buf, void *sgdata, size_t nbytes, int out)
+{
+ if (out)
+ memcpy(sgdata, buf, nbytes);
+ else
+ memcpy(buf, sgdata, nbytes);
+}
+
+void scatterwalk_start(struct scatter_walk *walk, struct scatterlist *sg)
+{
+ unsigned int rest_of_page;
+
+ walk->sg = sg;
+
+ walk->page = sg->page;
+ walk->len_this_segment = sg->length;
+
+ rest_of_page = PAGE_CACHE_SIZE - (sg->offset & (PAGE_CACHE_SIZE - 1));
+ walk->len_this_page = min(sg->length, rest_of_page);
+ walk->offset = sg->offset;
+}
+
+void scatterwalk_map(struct scatter_walk *walk, int out)
+{
+ walk->data = crypto_kmap(walk->page, out) + walk->offset;
+}
+
+static void scatterwalk_pagedone(struct scatter_walk *walk, int out,
+ unsigned int more)
+{
+ /* walk->data may be pointing the first byte of the next page;
+ however, we know we transfered at least one byte. So,
+ walk->data - 1 will be a virtual address in the mapped page. */
+
+ if (out)
+ flush_dcache_page(walk->page);
+
+ if (more) {
+ walk->len_this_segment -= walk->len_this_page;
+
+ if (walk->len_this_segment) {
+ walk->page++;
+ walk->len_this_page = min(walk->len_this_segment,
+ (unsigned)PAGE_CACHE_SIZE);
+ walk->offset = 0;
+ }
+ else
+ scatterwalk_start(walk, sg_next(walk->sg));
+ }
+}
+
+void scatterwalk_done(struct scatter_walk *walk, int out, int more)
+{
+ crypto_kunmap(walk->data, out);
+ if (walk->len_this_page == 0 || !more)
+ scatterwalk_pagedone(walk, out, more);
+}
+
+/*
+ * Do not call this unless the total length of all of the fragments
+ * has been verified as multiple of the block size.
+ */
+int scatterwalk_copychunks(void *buf, struct scatter_walk *walk,
+ size_t nbytes, int out)
+{
+ if (buf != walk->data) {
+ while (nbytes > walk->len_this_page) {
+ memcpy_dir(buf, walk->data, walk->len_this_page, out);
+ buf += walk->len_this_page;
+ nbytes -= walk->len_this_page;
+
+ crypto_kunmap(walk->data, out);
+ scatterwalk_pagedone(walk, out, 1);
+ scatterwalk_map(walk, out);
+ }
+
+ memcpy_dir(buf, walk->data, nbytes, out);
+ }
+
+ walk->offset += nbytes;
+ walk->len_this_page -= nbytes;
+ walk->len_this_segment -= nbytes;
+ return 0;
+}