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 | #ifndef _FC_FRAME_H_ |
9 | #define _FC_FRAME_H_ |
10 | |
11 | #include <linux/scatterlist.h> |
12 | #include <linux/skbuff.h> |
13 | #include <scsi/scsi_cmnd.h> |
14 | |
15 | #include <scsi/fc/fc_fs.h> |
16 | #include <scsi/fc/fc_fcp.h> |
17 | #include <scsi/fc/fc_encaps.h> |
18 | |
19 | #include <linux/if_ether.h> |
20 | |
21 | /* some helpful macros */ |
22 | |
23 | #define ntohll(x) be64_to_cpu(x) |
24 | #define htonll(x) cpu_to_be64(x) |
25 | |
26 | static inline u32 ntoh24(const u8 *p) |
27 | { |
28 | return (p[0] << 16) | (p[1] << 8) | p[2]; |
29 | } |
30 | |
31 | static inline void hton24(u8 *p, u32 v) |
32 | { |
33 | p[0] = (v >> 16) & 0xff; |
34 | p[1] = (v >> 8) & 0xff; |
35 | p[2] = v & 0xff; |
36 | } |
37 | |
38 | /* |
39 | * The fc_frame interface is used to pass frame data between functions. |
40 | * The frame includes the data buffer, length, and SOF / EOF delimiter types. |
41 | * A pointer to the port structure of the receiving port is also includeded. |
42 | */ |
43 | |
44 | #define FC_FRAME_HEADROOM 32 /* headroom for VLAN + FCoE headers */ |
45 | #define FC_FRAME_TAILROOM 8 /* trailer space for FCoE */ |
46 | |
47 | /* Max number of skb frags allowed, reserving one for fcoe_crc_eof page */ |
48 | #define FC_FRAME_SG_LEN (MAX_SKB_FRAGS - 1) |
49 | |
50 | #define fp_skb(fp) (&((fp)->skb)) |
51 | #define fr_hdr(fp) ((fp)->skb.data) |
52 | #define fr_len(fp) ((fp)->skb.len) |
53 | #define fr_cb(fp) ((struct fcoe_rcv_info *)&((fp)->skb.cb[0])) |
54 | #define fr_dev(fp) (fr_cb(fp)->fr_dev) |
55 | #define fr_seq(fp) (fr_cb(fp)->fr_seq) |
56 | #define fr_sof(fp) (fr_cb(fp)->fr_sof) |
57 | #define fr_eof(fp) (fr_cb(fp)->fr_eof) |
58 | #define fr_flags(fp) (fr_cb(fp)->fr_flags) |
59 | #define fr_encaps(fp) (fr_cb(fp)->fr_encaps) |
60 | #define fr_max_payload(fp) (fr_cb(fp)->fr_max_payload) |
61 | #define fr_fsp(fp) (fr_cb(fp)->fr_fsp) |
62 | #define fr_crc(fp) (fr_cb(fp)->fr_crc) |
63 | |
64 | struct fc_frame { |
65 | struct sk_buff skb; |
66 | }; |
67 | |
68 | struct fcoe_rcv_info { |
69 | struct fc_lport *fr_dev; /* transport layer private pointer */ |
70 | struct fc_seq *fr_seq; /* for use with exchange manager */ |
71 | struct fc_fcp_pkt *fr_fsp; /* for the corresponding fcp I/O */ |
72 | u32 fr_crc; |
73 | u16 fr_max_payload; /* max FC payload */ |
74 | u8 fr_sof; /* start of frame delimiter */ |
75 | u8 fr_eof; /* end of frame delimiter */ |
76 | u8 fr_flags; /* flags - see below */ |
77 | u8 fr_encaps; /* LLD encapsulation info (e.g. FIP) */ |
78 | u8 granted_mac[ETH_ALEN]; /* FCoE MAC address */ |
79 | }; |
80 | |
81 | |
82 | /* |
83 | * Get fc_frame pointer for an skb that's already been imported. |
84 | */ |
85 | static inline struct fcoe_rcv_info *fcoe_dev_from_skb(const struct sk_buff *skb) |
86 | { |
87 | BUILD_BUG_ON(sizeof(struct fcoe_rcv_info) > sizeof(skb->cb)); |
88 | return (struct fcoe_rcv_info *) skb->cb; |
89 | } |
90 | |
91 | /* |
92 | * fr_flags. |
93 | */ |
94 | #define FCPHF_CRC_UNCHECKED 0x01 /* CRC not computed, still appended */ |
95 | |
96 | /* |
97 | * Initialize a frame. |
98 | * We don't do a complete memset here for performance reasons. |
99 | * The caller must set fr_free, fr_hdr, fr_len, fr_sof, and fr_eof eventually. |
100 | */ |
101 | static inline void fc_frame_init(struct fc_frame *fp) |
102 | { |
103 | fr_dev(fp) = NULL; |
104 | fr_seq(fp) = NULL; |
105 | fr_flags(fp) = 0; |
106 | fr_encaps(fp) = 0; |
107 | } |
108 | |
109 | struct fc_frame *fc_frame_alloc_fill(struct fc_lport *, size_t payload_len); |
110 | struct fc_frame *_fc_frame_alloc(size_t payload_len); |
111 | |
112 | /* |
113 | * Allocate fc_frame structure and buffer. Set the initial length to |
114 | * payload_size + sizeof (struct fc_frame_header). |
115 | */ |
116 | static inline struct fc_frame *fc_frame_alloc(struct fc_lport *dev, size_t len) |
117 | { |
118 | struct fc_frame *fp; |
119 | |
120 | /* |
121 | * Note: Since len will often be a constant multiple of 4, |
122 | * this check will usually be evaluated and eliminated at compile time. |
123 | */ |
124 | if (len && len % 4) |
125 | fp = fc_frame_alloc_fill(dev, payload_len: len); |
126 | else |
127 | fp = _fc_frame_alloc(payload_len: len); |
128 | return fp; |
129 | } |
130 | |
131 | /* |
132 | * Free the fc_frame structure and buffer. |
133 | */ |
134 | static inline void fc_frame_free(struct fc_frame *fp) |
135 | { |
136 | kfree_skb(fp_skb(fp)); |
137 | } |
138 | |
139 | static inline int fc_frame_is_linear(struct fc_frame *fp) |
140 | { |
141 | return !skb_is_nonlinear(fp_skb(fp)); |
142 | } |
143 | |
144 | /* |
145 | * Get frame header from message in fc_frame structure. |
146 | * This version doesn't do a length check. |
147 | */ |
148 | static inline |
149 | struct fc_frame_header *(const struct fc_frame *fp) |
150 | { |
151 | return (struct fc_frame_header *)fr_hdr(fp); |
152 | } |
153 | |
154 | /* |
155 | * Get frame header from message in fc_frame structure. |
156 | * This hides a cast and provides a place to add some checking. |
157 | */ |
158 | static inline |
159 | struct fc_frame_header *(const struct fc_frame *fp) |
160 | { |
161 | WARN_ON(fr_len(fp) < sizeof(struct fc_frame_header)); |
162 | return __fc_frame_header_get(fp); |
163 | } |
164 | |
165 | /* |
166 | * Get source FC_ID (S_ID) from frame header in message. |
167 | */ |
168 | static inline u32 fc_frame_sid(const struct fc_frame *fp) |
169 | { |
170 | return ntoh24(p: __fc_frame_header_get(fp)->fh_s_id); |
171 | } |
172 | |
173 | /* |
174 | * Get destination FC_ID (D_ID) from frame header in message. |
175 | */ |
176 | static inline u32 fc_frame_did(const struct fc_frame *fp) |
177 | { |
178 | return ntoh24(p: __fc_frame_header_get(fp)->fh_d_id); |
179 | } |
180 | |
181 | /* |
182 | * Get frame payload from message in fc_frame structure. |
183 | * This hides a cast and provides a place to add some checking. |
184 | * The len parameter is the minimum length for the payload portion. |
185 | * Returns NULL if the frame is too short. |
186 | * |
187 | * This assumes the interesting part of the payload is in the first part |
188 | * of the buffer for received data. This may not be appropriate to use for |
189 | * buffers being transmitted. |
190 | */ |
191 | static inline void *fc_frame_payload_get(const struct fc_frame *fp, |
192 | size_t len) |
193 | { |
194 | void *pp = NULL; |
195 | |
196 | if (fr_len(fp) >= sizeof(struct fc_frame_header) + len) |
197 | pp = fc_frame_header_get(fp) + 1; |
198 | return pp; |
199 | } |
200 | |
201 | /* |
202 | * Get frame payload opcode (first byte) from message in fc_frame structure. |
203 | * This hides a cast and provides a place to add some checking. Return 0 |
204 | * if the frame has no payload. |
205 | */ |
206 | static inline u8 fc_frame_payload_op(const struct fc_frame *fp) |
207 | { |
208 | u8 *cp; |
209 | |
210 | cp = fc_frame_payload_get(fp, len: sizeof(u8)); |
211 | if (!cp) |
212 | return 0; |
213 | return *cp; |
214 | |
215 | } |
216 | |
217 | /* |
218 | * Get FC class from frame. |
219 | */ |
220 | static inline enum fc_class fc_frame_class(const struct fc_frame *fp) |
221 | { |
222 | return fc_sof_class(fr_sof(fp)); |
223 | } |
224 | |
225 | /* |
226 | * Check the CRC in a frame. |
227 | * The CRC immediately follows the last data item *AFTER* the length. |
228 | * The return value is zero if the CRC matches. |
229 | */ |
230 | u32 fc_frame_crc_check(struct fc_frame *); |
231 | |
232 | static inline u8 fc_frame_rctl(const struct fc_frame *fp) |
233 | { |
234 | return fc_frame_header_get(fp)->fh_r_ctl; |
235 | } |
236 | |
237 | static inline bool fc_frame_is_cmd(const struct fc_frame *fp) |
238 | { |
239 | return fc_frame_rctl(fp) == FC_RCTL_DD_UNSOL_CMD; |
240 | } |
241 | |
242 | /* |
243 | * Check for leaks. |
244 | * Print the frame header of any currently allocated frame, assuming there |
245 | * should be none at this point. |
246 | */ |
247 | void fc_frame_leak_check(void); |
248 | |
249 | static inline void __fc_fill_fc_hdr(struct fc_frame_header *fh, |
250 | enum fc_rctl r_ctl, |
251 | u32 did, u32 sid, enum fc_fh_type type, |
252 | u32 f_ctl, u32 parm_offset) |
253 | { |
254 | WARN_ON(r_ctl == 0); |
255 | fh->fh_r_ctl = r_ctl; |
256 | hton24(p: fh->fh_d_id, v: did); |
257 | hton24(p: fh->fh_s_id, v: sid); |
258 | fh->fh_type = type; |
259 | hton24(p: fh->fh_f_ctl, v: f_ctl); |
260 | fh->fh_cs_ctl = 0; |
261 | fh->fh_df_ctl = 0; |
262 | fh->fh_parm_offset = htonl(parm_offset); |
263 | } |
264 | |
265 | /** |
266 | * fill FC header fields in specified fc_frame |
267 | */ |
268 | static inline void fc_fill_fc_hdr(struct fc_frame *fp, enum fc_rctl r_ctl, |
269 | u32 did, u32 sid, enum fc_fh_type type, |
270 | u32 f_ctl, u32 parm_offset) |
271 | { |
272 | struct fc_frame_header *fh; |
273 | |
274 | fh = fc_frame_header_get(fp); |
275 | __fc_fill_fc_hdr(fh, r_ctl, did, sid, type, f_ctl, parm_offset); |
276 | } |
277 | |
278 | |
279 | #endif /* _FC_FRAME_H_ */ |
280 | |