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path: root/drivers/scsi/libfc/fc_frame.c
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Diffstat (limited to 'drivers/scsi/libfc/fc_frame.c')
-rw-r--r--drivers/scsi/libfc/fc_frame.c89
1 files changed, 89 insertions, 0 deletions
diff --git a/drivers/scsi/libfc/fc_frame.c b/drivers/scsi/libfc/fc_frame.c
new file mode 100644
index 00000000000..63fe00cfe66
--- /dev/null
+++ b/drivers/scsi/libfc/fc_frame.c
@@ -0,0 +1,89 @@
+/*
+ * Copyright(c) 2007 Intel Corporation. All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope 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.,
+ * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Maintained at www.Open-FCoE.org
+ */
+
+/*
+ * Frame allocation.
+ */
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/skbuff.h>
+#include <linux/crc32.h>
+
+#include <scsi/fc_frame.h>
+
+/*
+ * Check the CRC in a frame.
+ */
+u32 fc_frame_crc_check(struct fc_frame *fp)
+{
+ u32 crc;
+ u32 error;
+ const u8 *bp;
+ unsigned int len;
+
+ WARN_ON(!fc_frame_is_linear(fp));
+ fr_flags(fp) &= ~FCPHF_CRC_UNCHECKED;
+ len = (fr_len(fp) + 3) & ~3; /* round up length to include fill */
+ bp = (const u8 *) fr_hdr(fp);
+ crc = ~crc32(~0, bp, len);
+ error = crc ^ fr_crc(fp);
+ return error;
+}
+EXPORT_SYMBOL(fc_frame_crc_check);
+
+/*
+ * Allocate a frame intended to be sent via fcoe_xmit.
+ * Get an sk_buff for the frame and set the length.
+ */
+struct fc_frame *__fc_frame_alloc(size_t len)
+{
+ struct fc_frame *fp;
+ struct sk_buff *skb;
+
+ WARN_ON((len % sizeof(u32)) != 0);
+ len += sizeof(struct fc_frame_header);
+ skb = dev_alloc_skb(len + FC_FRAME_HEADROOM + FC_FRAME_TAILROOM);
+ if (!skb)
+ return NULL;
+ fp = (struct fc_frame *) skb;
+ fc_frame_init(fp);
+ skb_reserve(skb, FC_FRAME_HEADROOM);
+ skb_put(skb, len);
+ return fp;
+}
+EXPORT_SYMBOL(__fc_frame_alloc);
+
+
+struct fc_frame *fc_frame_alloc_fill(struct fc_lport *lp, size_t payload_len)
+{
+ struct fc_frame *fp;
+ size_t fill;
+
+ fill = payload_len % 4;
+ if (fill != 0)
+ fill = 4 - fill;
+ fp = __fc_frame_alloc(payload_len + fill);
+ if (fp) {
+ memset((char *) fr_hdr(fp) + payload_len, 0, fill);
+ /* trim is OK, we just allocated it so there are no fragments */
+ skb_trim(fp_skb(fp),
+ payload_len + sizeof(struct fc_frame_header));
+ }
+ return fp;
+}