Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / drivers / scsi / libfc / fc_frame.c

diff --git a/kernel/drivers/scsi/libfc/fc_frame.c b/kernel/drivers/scsi/libfc/fc_frame.c
new file mode 100644 (file)
index 0000000..0382ac0
--- /dev/null
+++ b/kernel/drivers/scsi/libfc/fc_frame.c
@@ -0,0 +1,91 @@
+/*
+ * 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 <linux/gfp.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.
+ * 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 = alloc_skb_fclone(len + FC_FRAME_HEADROOM + FC_FRAME_TAILROOM +
+                              NET_SKB_PAD, GFP_ATOMIC);
+       if (!skb)
+               return NULL;
+       skb_reserve(skb, NET_SKB_PAD + FC_FRAME_HEADROOM);
+       fp = (struct fc_frame *) skb;
+       fc_frame_init(fp);
+       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;
+}
+EXPORT_SYMBOL(fc_frame_alloc_fill);