drivers/infiniband/core/smi.c

   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  *
   9  * This software is available to you under a choice of one of two
  10  * licenses.  You may choose to be licensed under the terms of the GNU
  11  * General Public License (GPL) Version 2, available from the file
  12  * COPYING in the main directory of this source tree, or the
  13  * OpenIB.org BSD license below:
  14  *
  15  *     Redistribution and use in source and binary forms, with or
  16  *     without modification, are permitted provided that the following
  17  *     conditions are met:
  18  *
  19  *      - Redistributions of source code must retain the above
  20  *        copyright notice, this list of conditions and the following
  21  *        disclaimer.
  22  *
  23  *      - Redistributions in binary form must reproduce the above
  24  *        copyright notice, this list of conditions and the following
  25  *        disclaimer in the documentation and/or other materials
  26  *        provided with the distribution.
  27  *
  28  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  29  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  30  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  31  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  32  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  33  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  34  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  35  * SOFTWARE.
  36  *
  37  */
  38
  39 #include <rdma/ib_smi.h>
  40 #include "smi.h"
  41
  42 /*
  43  * Fixup a directed route SMP for sending
  44  * Return 0 if the SMP should be discarded
  45  */
  46 enum smi_action smi_handle_dr_smp_send(struct ib_smp *smp,
  47                                        u8 node_type, int port_num)
  48 {
  49         u8 hop_ptr, hop_cnt;
  50
  51         hop_ptr = smp->hop_ptr;
  52         hop_cnt = smp->hop_cnt;
  53
  54         /* See section 14.2.2.2, Vol 1 IB spec */
  55         if (!ib_get_smp_direction(smp)) {
  56                 /* C14-9:1 */
  57                 if (hop_cnt && hop_ptr == 0) {
  58                         smp->hop_ptr++;
  59                         return (smp->initial_path[smp->hop_ptr] ==
  60                                 port_num ? IB_SMI_HANDLE : IB_SMI_DISCARD);
  61                 }
  62
  63                 /* C14-9:2 */
  64                 if (hop_ptr && hop_ptr < hop_cnt) {
  65                         if (node_type != RDMA_NODE_IB_SWITCH)
  66                                 return IB_SMI_DISCARD;
  67
  68                         /* smp->return_path set when received */
  69                         smp->hop_ptr++;
  70                         return (smp->initial_path[smp->hop_ptr] ==
  71                                 port_num ? IB_SMI_HANDLE : IB_SMI_DISCARD);
  72                 }
  73
  74                 /* C14-9:3 -- We're at the end of the DR segment of path */
  75                 if (hop_ptr == hop_cnt) {
  76                         /* smp->return_path set when received */
  77                         smp->hop_ptr++;
  78                         return (node_type == RDMA_NODE_IB_SWITCH ||
  79                                 smp->dr_dlid == IB_LID_PERMISSIVE ?
  80                                 IB_SMI_HANDLE : IB_SMI_DISCARD);
  81                 }
  82
  83                 /* C14-9:4 -- hop_ptr = hop_cnt + 1 -> give to SMA/SM */
  84                 /* C14-9:5 -- Fail unreasonable hop pointer */
  85                 return (hop_ptr == hop_cnt + 1 ? IB_SMI_HANDLE : IB_SMI_DISCARD);
  86
  87         } else {
  88                 /* C14-13:1 */
  89                 if (hop_cnt && hop_ptr == hop_cnt + 1) {
  90                         smp->hop_ptr--;
  91                         return (smp->return_path[smp->hop_ptr] ==
  92                                 port_num ? IB_SMI_HANDLE : IB_SMI_DISCARD);
  93                 }
  94
  95                 /* C14-13:2 */
  96                 if (2 <= hop_ptr && hop_ptr <= hop_cnt) {
  97                         if (node_type != RDMA_NODE_IB_SWITCH)
  98                                 return IB_SMI_DISCARD;
  99
 100                         smp->hop_ptr--;
 101                         return (smp->return_path[smp->hop_ptr] ==
 102                                 port_num ? IB_SMI_HANDLE : IB_SMI_DISCARD);
 103                 }
 104
 105                 /* C14-13:3 -- at the end of the DR segment of path */
 106                 if (hop_ptr == 1) {
 107                         smp->hop_ptr--;
 108                         /* C14-13:3 -- SMPs destined for SM shouldn't be here */
 109                         return (node_type == RDMA_NODE_IB_SWITCH ||
 110                                 smp->dr_slid == IB_LID_PERMISSIVE ?
 111                                 IB_SMI_HANDLE : IB_SMI_DISCARD);
 112                 }
 113
 114                 /* C14-13:4 -- hop_ptr = 0 -> should have gone to SM */
 115                 if (hop_ptr == 0)
 116                         return IB_SMI_HANDLE;
 117
 118                 /* C14-13:5 -- Check for unreasonable hop pointer */
 119                 return IB_SMI_DISCARD;
 120         }
 121 }
 122
 123 /*
 124  * Adjust information for a received SMP
 125  * Return 0 if the SMP should be dropped
 126  */
 127 enum smi_action smi_handle_dr_smp_recv(struct ib_smp *smp, u8 node_type,
 128                                        int port_num, int phys_port_cnt)
 129 {
 130         u8 hop_ptr, hop_cnt;
 131
 132         hop_ptr = smp->hop_ptr;
 133         hop_cnt = smp->hop_cnt;
 134
 135         /* See section 14.2.2.2, Vol 1 IB spec */
 136         if (!ib_get_smp_direction(smp)) {
 137                 /* C14-9:1 -- sender should have incremented hop_ptr */
 138                 if (hop_cnt && hop_ptr == 0)
 139                         return IB_SMI_DISCARD;
 140
 141                 /* C14-9:2 -- intermediate hop */
 142                 if (hop_ptr && hop_ptr < hop_cnt) {
 143                         if (node_type != RDMA_NODE_IB_SWITCH)
 144                                 return IB_SMI_DISCARD;
 145
 146                         smp->return_path[hop_ptr] = port_num;
 147                         /* smp->hop_ptr updated when sending */
 148                         return (smp->initial_path[hop_ptr+1] <= phys_port_cnt ?
 149                                 IB_SMI_HANDLE : IB_SMI_DISCARD);
 150                 }
 151
 152                 /* C14-9:3 -- We're at the end of the DR segment of path */
 153                 if (hop_ptr == hop_cnt) {
 154                         if (hop_cnt)
 155                                 smp->return_path[hop_ptr] = port_num;
 156                         /* smp->hop_ptr updated when sending */
 157
 158                         return (node_type == RDMA_NODE_IB_SWITCH ||
 159                                 smp->dr_dlid == IB_LID_PERMISSIVE ?
 160                                 IB_SMI_HANDLE : IB_SMI_DISCARD);
 161                 }
 162
 163                 /* C14-9:4 -- hop_ptr = hop_cnt + 1 -> give to SMA/SM */
 164                 /* C14-9:5 -- fail unreasonable hop pointer */
 165                 return (hop_ptr == hop_cnt + 1 ? IB_SMI_HANDLE : IB_SMI_DISCARD);
 166
 167         } else {
 168
 169                 /* C14-13:1 */
 170                 if (hop_cnt && hop_ptr == hop_cnt + 1) {
 171                         smp->hop_ptr--;
 172                         return (smp->return_path[smp->hop_ptr] ==
 173                                 port_num ? IB_SMI_HANDLE : IB_SMI_DISCARD);
 174                 }
 175
 176                 /* C14-13:2 */
 177                 if (2 <= hop_ptr && hop_ptr <= hop_cnt) {
 178                         if (node_type != RDMA_NODE_IB_SWITCH)
 179                                 return IB_SMI_DISCARD;
 180
 181                         /* smp->hop_ptr updated when sending */
 182                         return (smp->return_path[hop_ptr-1] <= phys_port_cnt ?
 183                                 IB_SMI_HANDLE : IB_SMI_DISCARD);
 184                 }
 185
 186                 /* C14-13:3 -- We're at the end of the DR segment of path */
 187                 if (hop_ptr == 1) {
 188                         if (smp->dr_slid == IB_LID_PERMISSIVE) {
 189                                 /* giving SMP to SM - update hop_ptr */
 190                                 smp->hop_ptr--;
 191                                 return IB_SMI_HANDLE;
 192                         }
 193                         /* smp->hop_ptr updated when sending */
 194                         return (node_type == RDMA_NODE_IB_SWITCH ?
 195                                 IB_SMI_HANDLE : IB_SMI_DISCARD);
 196                 }
 197
 198                 /* C14-13:4 -- hop_ptr = 0 -> give to SM */
 199                 /* C14-13:5 -- Check for unreasonable hop pointer */
 200                 return (hop_ptr == 0 ? IB_SMI_HANDLE : IB_SMI_DISCARD);
 201         }
 202 }
 203
 204 enum smi_forward_action smi_check_forward_dr_smp(struct ib_smp *smp)
 205 {
 206         u8 hop_ptr, hop_cnt;
 207
 208         hop_ptr = smp->hop_ptr;
 209         hop_cnt = smp->hop_cnt;
 210
 211         if (!ib_get_smp_direction(smp)) {
 212                 /* C14-9:2 -- intermediate hop */
 213                 if (hop_ptr && hop_ptr < hop_cnt)
 214                         return IB_SMI_FORWARD;
 215
 216                 /* C14-9:3 -- at the end of the DR segment of path */
 217                 if (hop_ptr == hop_cnt)
 218                         return (smp->dr_dlid == IB_LID_PERMISSIVE ?
 219                                 IB_SMI_SEND : IB_SMI_LOCAL);
 220
 221                 /* C14-9:4 -- hop_ptr = hop_cnt + 1 -> give to SMA/SM */
 222                 if (hop_ptr == hop_cnt + 1)
 223                         return IB_SMI_SEND;
 224         } else {
 225                 /* C14-13:2  -- intermediate hop */
 226                 if (2 <= hop_ptr && hop_ptr <= hop_cnt)
 227                         return IB_SMI_FORWARD;
 228
 229                 /* C14-13:3 -- at the end of the DR segment of path */
 230                 if (hop_ptr == 1)
 231                         return (smp->dr_slid != IB_LID_PERMISSIVE ?
 232                                 IB_SMI_SEND : IB_SMI_LOCAL);
 233         }
 234         return IB_SMI_LOCAL;
 235 }
 236
 237 /*
 238  * Return the forwarding port number from initial_path for outgoing SMP and
 239  * from return_path for returning SMP
 240  */
 241 int smi_get_fwd_port(struct ib_smp *smp)
 242 {
 243         return (!ib_get_smp_direction(smp) ? smp->initial_path[smp->hop_ptr+1] :
 244                 smp->return_path[smp->hop_ptr-1]);
 245 }