diff options
Diffstat (limited to 'drivers/scsi/libfc/fc_frame.c')
-rw-r--r-- | drivers/scsi/libfc/fc_frame.c | 89 |
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 000000000000..63fe00cfe667 --- /dev/null +++ b/drivers/scsi/libfc/fc_frame.c | |||
@@ -0,0 +1,89 @@ | |||
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 | |||
28 | #include <scsi/fc_frame.h> | ||
29 | |||
30 | /* | ||
31 | * Check the CRC in a frame. | ||
32 | */ | ||
33 | u32 fc_frame_crc_check(struct fc_frame *fp) | ||
34 | { | ||
35 | u32 crc; | ||
36 | u32 error; | ||
37 | const u8 *bp; | ||
38 | unsigned int len; | ||
39 | |||
40 | WARN_ON(!fc_frame_is_linear(fp)); | ||
41 | fr_flags(fp) &= ~FCPHF_CRC_UNCHECKED; | ||
42 | len = (fr_len(fp) + 3) & ~3; /* round up length to include fill */ | ||
43 | bp = (const u8 *) fr_hdr(fp); | ||
44 | crc = ~crc32(~0, bp, len); | ||
45 | error = crc ^ fr_crc(fp); | ||
46 | return error; | ||
47 | } | ||
48 | EXPORT_SYMBOL(fc_frame_crc_check); | ||
49 | |||
50 | /* | ||
51 | * Allocate a frame intended to be sent via fcoe_xmit. | ||
52 | * Get an sk_buff for the frame and set the length. | ||
53 | */ | ||
54 | struct fc_frame *__fc_frame_alloc(size_t len) | ||
55 | { | ||
56 | struct fc_frame *fp; | ||
57 | struct sk_buff *skb; | ||
58 | |||
59 | WARN_ON((len % sizeof(u32)) != 0); | ||
60 | len += sizeof(struct fc_frame_header); | ||
61 | skb = dev_alloc_skb(len + FC_FRAME_HEADROOM + FC_FRAME_TAILROOM); | ||
62 | if (!skb) | ||
63 | return NULL; | ||
64 | fp = (struct fc_frame *) skb; | ||
65 | fc_frame_init(fp); | ||
66 | skb_reserve(skb, FC_FRAME_HEADROOM); | ||
67 | skb_put(skb, len); | ||
68 | return fp; | ||
69 | } | ||
70 | EXPORT_SYMBOL(__fc_frame_alloc); | ||
71 | |||
72 | |||
73 | struct fc_frame *fc_frame_alloc_fill(struct fc_lport *lp, size_t payload_len) | ||
74 | { | ||
75 | struct fc_frame *fp; | ||
76 | size_t fill; | ||
77 | |||
78 | fill = payload_len % 4; | ||
79 | if (fill != 0) | ||
80 | fill = 4 - fill; | ||
81 | fp = __fc_frame_alloc(payload_len + fill); | ||
82 | if (fp) { | ||
83 | memset((char *) fr_hdr(fp) + payload_len, 0, fill); | ||
84 | /* trim is OK, we just allocated it so there are no fragments */ | ||
85 | skb_trim(fp_skb(fp), | ||
86 | payload_len + sizeof(struct fc_frame_header)); | ||
87 | } | ||
88 | return fp; | ||
89 | } | ||