2 * Copyright(c) 2007 Intel Corporation. All rights reserved.
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms and conditions of the GNU General Public License,
6 * version 2, as published by the Free Software Foundation.
8 * This program is distributed in the hope it will be useful, but WITHOUT
9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
13 * You should have received a copy of the GNU General Public License along with
14 * this program; if not, write to the Free Software Foundation, Inc.,
15 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
17 * Maintained at www.Open-FCoE.org
23 #include <linux/module.h>
24 #include <linux/kernel.h>
25 #include <linux/skbuff.h>
26 #include <linux/crc32.h>
27 #include <linux/gfp.h>
29 #include <scsi/fc_frame.h>
32 * Check the CRC in a frame.
34 u32 fc_frame_crc_check(struct fc_frame *fp)
41 WARN_ON(!fc_frame_is_linear(fp));
42 fr_flags(fp) &= ~FCPHF_CRC_UNCHECKED;
43 len = (fr_len(fp) + 3) & ~3; /* round up length to include fill */
44 bp = (const u8 *) fr_hdr(fp);
45 crc = ~crc32(~0, bp, len);
46 error = crc ^ fr_crc(fp);
49 EXPORT_SYMBOL(fc_frame_crc_check);
52 * Allocate a frame intended to be sent.
53 * Get an sk_buff for the frame and set the length.
55 struct fc_frame *_fc_frame_alloc(size_t len)
60 WARN_ON((len % sizeof(u32)) != 0);
61 len += sizeof(struct fc_frame_header);
62 skb = alloc_skb_fclone(len + FC_FRAME_HEADROOM + FC_FRAME_TAILROOM +
63 NET_SKB_PAD, GFP_ATOMIC);
66 skb_reserve(skb, NET_SKB_PAD + FC_FRAME_HEADROOM);
67 fp = (struct fc_frame *) skb;
72 EXPORT_SYMBOL(_fc_frame_alloc);
74 struct fc_frame *fc_frame_alloc_fill(struct fc_lport *lp, size_t payload_len)
79 fill = payload_len % 4;
82 fp = _fc_frame_alloc(payload_len + fill);
84 memset((char *) fr_hdr(fp) + payload_len, 0, fill);
85 /* trim is OK, we just allocated it so there are no fragments */
87 payload_len + sizeof(struct fc_frame_header));
91 EXPORT_SYMBOL(fc_frame_alloc_fill);