1// SPDX-License-Identifier: GPL-2.0-only
 2/*
 3 * Copyright(c) 2007 Intel Corporation. All rights reserved.
 
 
 
 
 
 
 
 
 
 
 
 
 
 4 *
 5 * Maintained at www.Open-FCoE.org
 6 */
 7
 8/*
 9 * Frame allocation.
10 */
11#include <linux/module.h>
12#include <linux/kernel.h>
13#include <linux/skbuff.h>
14#include <linux/crc32.h>
15#include <linux/gfp.h>
16
17#include <scsi/fc_frame.h>
18
19/*
20 * Check the CRC in a frame.
21 */
22u32 fc_frame_crc_check(struct fc_frame *fp)
23{
24	u32 crc;
25	u32 error;
26	const u8 *bp;
27	unsigned int len;
28
29	WARN_ON(!fc_frame_is_linear(fp));
30	fr_flags(fp) &= ~FCPHF_CRC_UNCHECKED;
31	len = (fr_len(fp) + 3) & ~3;	/* round up length to include fill */
32	bp = (const u8 *) fr_hdr(fp);
33	crc = ~crc32(~0, bp, len);
34	error = crc ^ fr_crc(fp);
35	return error;
36}
37EXPORT_SYMBOL(fc_frame_crc_check);
38
39/*
40 * Allocate a frame intended to be sent.
41 * Get an sk_buff for the frame and set the length.
42 */
43struct fc_frame *_fc_frame_alloc(size_t len)
44{
45	struct fc_frame *fp;
46	struct sk_buff *skb;
47
48	WARN_ON((len % sizeof(u32)) != 0);
49	len += sizeof(struct fc_frame_header);
50	skb = alloc_skb_fclone(len + FC_FRAME_HEADROOM + FC_FRAME_TAILROOM +
51			       NET_SKB_PAD, GFP_ATOMIC);
52	if (!skb)
53		return NULL;
54	skb_reserve(skb, NET_SKB_PAD + FC_FRAME_HEADROOM);
55	fp = (struct fc_frame *) skb;
56	fc_frame_init(fp);
57	skb_put(skb, len);
58	return fp;
59}
60EXPORT_SYMBOL(_fc_frame_alloc);
61
62struct fc_frame *fc_frame_alloc_fill(struct fc_lport *lp, size_t payload_len)
63{
64	struct fc_frame *fp;
65	size_t fill;
66
67	fill = payload_len % 4;
68	if (fill != 0)
69		fill = 4 - fill;
70	fp = _fc_frame_alloc(payload_len + fill);
71	if (fp) {
72		memset((char *) fr_hdr(fp) + payload_len, 0, fill);
73		/* trim is OK, we just allocated it so there are no fragments */
74		skb_trim(fp_skb(fp),
75			 payload_len + sizeof(struct fc_frame_header));
76	}
77	return fp;
78}
79EXPORT_SYMBOL(fc_frame_alloc_fill);

 
 1/*
 2 * Copyright(c) 2007 Intel Corporation. All rights reserved.
 3 *
 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.
 7 *
 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
11 * more details.
12 *
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.
16 *
17 * Maintained at www.Open-FCoE.org
18 */
19
20/*
21 * Frame allocation.
22 */
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>
28
29#include <scsi/fc_frame.h>
30
31/*
32 * Check the CRC in a frame.
33 */
34u32 fc_frame_crc_check(struct fc_frame *fp)
35{
36	u32 crc;
37	u32 error;
38	const u8 *bp;
39	unsigned int len;
40
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);
47	return error;
48}
49EXPORT_SYMBOL(fc_frame_crc_check);
50
51/*
52 * Allocate a frame intended to be sent.
53 * Get an sk_buff for the frame and set the length.
54 */
55struct fc_frame *_fc_frame_alloc(size_t len)
56{
57	struct fc_frame *fp;
58	struct sk_buff *skb;
59
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);
64	if (!skb)
65		return NULL;
66	skb_reserve(skb, NET_SKB_PAD + FC_FRAME_HEADROOM);
67	fp = (struct fc_frame *) skb;
68	fc_frame_init(fp);
69	skb_put(skb, len);
70	return fp;
71}
72EXPORT_SYMBOL(_fc_frame_alloc);
73
74struct fc_frame *fc_frame_alloc_fill(struct fc_lport *lp, size_t payload_len)
75{
76	struct fc_frame *fp;
77	size_t fill;
78
79	fill = payload_len % 4;
80	if (fill != 0)
81		fill = 4 - fill;
82	fp = _fc_frame_alloc(payload_len + fill);
83	if (fp) {
84		memset((char *) fr_hdr(fp) + payload_len, 0, fill);
85		/* trim is OK, we just allocated it so there are no fragments */
86		skb_trim(fp_skb(fp),
87			 payload_len + sizeof(struct fc_frame_header));
88	}
89	return fp;
90}
91EXPORT_SYMBOL(fc_frame_alloc_fill);