1 files changed, 79 insertions, 0 deletions
diff --git a/drivers/scsi/libfc/fc_frame.c b/drivers/scsi/libfc/fc_frame.c
new file mode 100644
index 000000000..f3aefb2de
--- /dev/null
+++ b/drivers/scsi/libfc/fc_frame.c
@@ -0,0 +1,79 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright(c) 2007 Intel Corporation. All rights reserved.
+ *
+ * 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);