1/*
2 * Copyright (c) 2004, 2005 Mellanox Technologies Ltd.  All rights reserved.
3 * Copyright (c) 2004, 2005 Infinicon Corporation.  All rights reserved.
4 * Copyright (c) 2004, 2005 Intel Corporation.  All rights reserved.
5 * Copyright (c) 2004, 2005 Topspin Corporation.  All rights reserved.
6 * Copyright (c) 2004-2007 Voltaire Corporation.  All rights reserved.
7 * Copyright (c) 2005 Sun Microsystems, Inc. All rights reserved.
8 * Copyright (c) 2014 Intel Corporation.  All rights reserved.
9 *
10 * This software is available to you under a choice of one of two
11 * licenses.  You may choose to be licensed under the terms of the GNU
12 * General Public License (GPL) Version 2, available from the file
13 * COPYING in the main directory of this source tree, or the
14 * OpenIB.org BSD license below:
15 *
16 *     Redistribution and use in source and binary forms, with or
17 *     without modification, are permitted provided that the following
18 *     conditions are met:
19 *
20 *      - Redistributions of source code must retain the above
21 *        copyright notice, this list of conditions and the following
22 *        disclaimer.
23 *
24 *      - Redistributions in binary form must reproduce the above
25 *        copyright notice, this list of conditions and the following
26 *        disclaimer in the documentation and/or other materials
27 *        provided with the distribution.
28 *
29 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
30 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
31 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
32 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
33 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
34 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
35 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
36 * SOFTWARE.
37 *
38 */
39
40#include <rdma/ib_smi.h>
41#include "smi.h"
42#include "opa_smi.h"
43
44static enum smi_action __smi_handle_dr_smp_send(bool is_switch, int port_num,
45						u8 *hop_ptr, u8 hop_cnt,
46						const u8 *initial_path,
47						const u8 *return_path,
48						u8 direction,
49						bool dr_dlid_is_permissive,
50						bool dr_slid_is_permissive)
51{
52	/* See section 14.2.2.2, Vol 1 IB spec */
53	/* C14-6 -- valid hop_cnt values are from 0 to 63 */
54	if (hop_cnt >= IB_SMP_MAX_PATH_HOPS)
55		return IB_SMI_DISCARD;
56
57	if (!direction) {
58		/* C14-9:1 */
59		if (hop_cnt && *hop_ptr == 0) {
60			(*hop_ptr)++;
61			return (initial_path[*hop_ptr] ==
62				port_num ? IB_SMI_HANDLE : IB_SMI_DISCARD);
63		}
64
65		/* C14-9:2 */
66		if (*hop_ptr && *hop_ptr < hop_cnt) {
67			if (!is_switch)
68				return IB_SMI_DISCARD;
69
70			/* return_path set when received */
71			(*hop_ptr)++;
72			return (initial_path[*hop_ptr] ==
73				port_num ? IB_SMI_HANDLE : IB_SMI_DISCARD);
74		}
75
76		/* C14-9:3 -- We're at the end of the DR segment of path */
77		if (*hop_ptr == hop_cnt) {
78			/* return_path set when received */
79			(*hop_ptr)++;
80			return (is_switch ||
81				dr_dlid_is_permissive ?
82				IB_SMI_HANDLE : IB_SMI_DISCARD);
83		}
84
85		/* C14-9:4 -- hop_ptr = hop_cnt + 1 -> give to SMA/SM */
86		/* C14-9:5 -- Fail unreasonable hop pointer */
87		return (*hop_ptr == hop_cnt + 1 ? IB_SMI_HANDLE : IB_SMI_DISCARD);
88
89	} else {
90		/* C14-13:1 */
91		if (hop_cnt && *hop_ptr == hop_cnt + 1) {
92			(*hop_ptr)--;
93			return (return_path[*hop_ptr] ==
94				port_num ? IB_SMI_HANDLE : IB_SMI_DISCARD);
95		}
96
97		/* C14-13:2 */
98		if (2 <= *hop_ptr && *hop_ptr <= hop_cnt) {
99			if (!is_switch)
100				return IB_SMI_DISCARD;
101
102			(*hop_ptr)--;
103			return (return_path[*hop_ptr] ==
104				port_num ? IB_SMI_HANDLE : IB_SMI_DISCARD);
105		}
106
107		/* C14-13:3 -- at the end of the DR segment of path */
108		if (*hop_ptr == 1) {
109			(*hop_ptr)--;
110			/* C14-13:3 -- SMPs destined for SM shouldn't be here */
111			return (is_switch ||
112				dr_slid_is_permissive ?
113				IB_SMI_HANDLE : IB_SMI_DISCARD);
114		}
115
116		/* C14-13:4 -- hop_ptr = 0 -> should have gone to SM */
117		if (*hop_ptr == 0)
118			return IB_SMI_HANDLE;
119
120		/* C14-13:5 -- Check for unreasonable hop pointer */
121		return IB_SMI_DISCARD;
122	}
123}
124
125/*
126 * Fixup a directed route SMP for sending
127 * Return IB_SMI_DISCARD if the SMP should be discarded
128 */
129enum smi_action smi_handle_dr_smp_send(struct ib_smp *smp,
130				       bool is_switch, int port_num)
131{
132	return __smi_handle_dr_smp_send(is_switch, port_num,
133					&smp->hop_ptr, smp->hop_cnt,
134					smp->initial_path,
135					smp->return_path,
136					ib_get_smp_direction(smp),
137					smp->dr_dlid == IB_LID_PERMISSIVE,
138					smp->dr_slid == IB_LID_PERMISSIVE);
139}
140
141enum smi_action opa_smi_handle_dr_smp_send(struct opa_smp *smp,
142				       bool is_switch, int port_num)
143{
144	return __smi_handle_dr_smp_send(is_switch, port_num,
145					&smp->hop_ptr, smp->hop_cnt,
146					smp->route.dr.initial_path,
147					smp->route.dr.return_path,
148					opa_get_smp_direction(smp),
149					smp->route.dr.dr_dlid ==
150					OPA_LID_PERMISSIVE,
151					smp->route.dr.dr_slid ==
152					OPA_LID_PERMISSIVE);
153}
154
155static enum smi_action __smi_handle_dr_smp_recv(bool is_switch, int port_num,
156						int phys_port_cnt,
157						u8 *hop_ptr, u8 hop_cnt,
158						const u8 *initial_path,
159						u8 *return_path,
160						u8 direction,
161						bool dr_dlid_is_permissive,
162						bool dr_slid_is_permissive)
163{
164	/* See section 14.2.2.2, Vol 1 IB spec */
165	/* C14-6 -- valid hop_cnt values are from 0 to 63 */
166	if (hop_cnt >= IB_SMP_MAX_PATH_HOPS)
167		return IB_SMI_DISCARD;
168
169	if (!direction) {
170		/* C14-9:1 -- sender should have incremented hop_ptr */
171		if (hop_cnt && *hop_ptr == 0)
172			return IB_SMI_DISCARD;
173
174		/* C14-9:2 -- intermediate hop */
175		if (*hop_ptr && *hop_ptr < hop_cnt) {
176			if (!is_switch)
177				return IB_SMI_DISCARD;
178
179			return_path[*hop_ptr] = port_num;
180			/* hop_ptr updated when sending */
181			return (initial_path[*hop_ptr+1] <= phys_port_cnt ?
182				IB_SMI_HANDLE : IB_SMI_DISCARD);
183		}
184
185		/* C14-9:3 -- We're at the end of the DR segment of path */
186		if (*hop_ptr == hop_cnt) {
187			if (hop_cnt)
188				return_path[*hop_ptr] = port_num;
189			/* hop_ptr updated when sending */
190
191			return (is_switch ||
192				dr_dlid_is_permissive ?
193				IB_SMI_HANDLE : IB_SMI_DISCARD);
194		}
195
196		/* C14-9:4 -- hop_ptr = hop_cnt + 1 -> give to SMA/SM */
197		/* C14-9:5 -- fail unreasonable hop pointer */
198		return (*hop_ptr == hop_cnt + 1 ? IB_SMI_HANDLE : IB_SMI_DISCARD);
199
200	} else {
201
202		/* C14-13:1 */
203		if (hop_cnt && *hop_ptr == hop_cnt + 1) {
204			(*hop_ptr)--;
205			return (return_path[*hop_ptr] ==
206				port_num ? IB_SMI_HANDLE : IB_SMI_DISCARD);
207		}
208
209		/* C14-13:2 */
210		if (2 <= *hop_ptr && *hop_ptr <= hop_cnt) {
211			if (!is_switch)
212				return IB_SMI_DISCARD;
213
214			/* hop_ptr updated when sending */
215			return (return_path[*hop_ptr-1] <= phys_port_cnt ?
216				IB_SMI_HANDLE : IB_SMI_DISCARD);
217		}
218
219		/* C14-13:3 -- We're at the end of the DR segment of path */
220		if (*hop_ptr == 1) {
221			if (dr_slid_is_permissive) {
222				/* giving SMP to SM - update hop_ptr */
223				(*hop_ptr)--;
224				return IB_SMI_HANDLE;
225			}
226			/* hop_ptr updated when sending */
227			return (is_switch ? IB_SMI_HANDLE : IB_SMI_DISCARD);
228		}
229
230		/* C14-13:4 -- hop_ptr = 0 -> give to SM */
231		/* C14-13:5 -- Check for unreasonable hop pointer */
232		return (*hop_ptr == 0 ? IB_SMI_HANDLE : IB_SMI_DISCARD);
233	}
234}
235
236/*
237 * Adjust information for a received SMP
238 * Return IB_SMI_DISCARD if the SMP should be dropped
239 */
240enum smi_action smi_handle_dr_smp_recv(struct ib_smp *smp, bool is_switch,
241				       int port_num, int phys_port_cnt)
242{
243	return __smi_handle_dr_smp_recv(is_switch, port_num, phys_port_cnt,
244					&smp->hop_ptr, smp->hop_cnt,
245					smp->initial_path,
246					smp->return_path,
247					ib_get_smp_direction(smp),
248					smp->dr_dlid == IB_LID_PERMISSIVE,
249					smp->dr_slid == IB_LID_PERMISSIVE);
250}
251
252/*
253 * Adjust information for a received SMP
254 * Return IB_SMI_DISCARD if the SMP should be dropped
255 */
256enum smi_action opa_smi_handle_dr_smp_recv(struct opa_smp *smp, bool is_switch,
257					   int port_num, int phys_port_cnt)
258{
259	return __smi_handle_dr_smp_recv(is_switch, port_num, phys_port_cnt,
260					&smp->hop_ptr, smp->hop_cnt,
261					smp->route.dr.initial_path,
262					smp->route.dr.return_path,
263					opa_get_smp_direction(smp),
264					smp->route.dr.dr_dlid ==
265					OPA_LID_PERMISSIVE,
266					smp->route.dr.dr_slid ==
267					OPA_LID_PERMISSIVE);
268}
269
270static enum smi_forward_action __smi_check_forward_dr_smp(u8 hop_ptr, u8 hop_cnt,
271							  u8 direction,
272							  bool dr_dlid_is_permissive,
273							  bool dr_slid_is_permissive)
274{
275	if (!direction) {
276		/* C14-9:2 -- intermediate hop */
277		if (hop_ptr && hop_ptr < hop_cnt)
278			return IB_SMI_FORWARD;
279
280		/* C14-9:3 -- at the end of the DR segment of path */
281		if (hop_ptr == hop_cnt)
282			return (dr_dlid_is_permissive ?
283				IB_SMI_SEND : IB_SMI_LOCAL);
284
285		/* C14-9:4 -- hop_ptr = hop_cnt + 1 -> give to SMA/SM */
286		if (hop_ptr == hop_cnt + 1)
287			return IB_SMI_SEND;
288	} else {
289		/* C14-13:2  -- intermediate hop */
290		if (2 <= hop_ptr && hop_ptr <= hop_cnt)
291			return IB_SMI_FORWARD;
292
293		/* C14-13:3 -- at the end of the DR segment of path */
294		if (hop_ptr == 1)
295			return (!dr_slid_is_permissive ?
296				IB_SMI_SEND : IB_SMI_LOCAL);
297	}
298	return IB_SMI_LOCAL;
299
300}
301
302enum smi_forward_action smi_check_forward_dr_smp(struct ib_smp *smp)
303{
304	return __smi_check_forward_dr_smp(smp->hop_ptr, smp->hop_cnt,
305					  ib_get_smp_direction(smp),
306					  smp->dr_dlid == IB_LID_PERMISSIVE,
307					  smp->dr_slid == IB_LID_PERMISSIVE);
308}
309
310enum smi_forward_action opa_smi_check_forward_dr_smp(struct opa_smp *smp)
311{
312	return __smi_check_forward_dr_smp(smp->hop_ptr, smp->hop_cnt,
313					  opa_get_smp_direction(smp),
314					  smp->route.dr.dr_dlid ==
315					  OPA_LID_PERMISSIVE,
316					  smp->route.dr.dr_slid ==
317					  OPA_LID_PERMISSIVE);
318}
319
320/*
321 * Return the forwarding port number from initial_path for outgoing SMP and
322 * from return_path for returning SMP
323 */
324int smi_get_fwd_port(struct ib_smp *smp)
325{
326	return (!ib_get_smp_direction(smp) ? smp->initial_path[smp->hop_ptr+1] :
327		smp->return_path[smp->hop_ptr-1]);
328}
329
330/*
331 * Return the forwarding port number from initial_path for outgoing SMP and
332 * from return_path for returning SMP
333 */
334int opa_smi_get_fwd_port(struct opa_smp *smp)
335{
336	return !opa_get_smp_direction(smp) ? smp->route.dr.initial_path[smp->hop_ptr+1] :
337		smp->route.dr.return_path[smp->hop_ptr-1];
338}
339