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         /* C14-6 -- valid hop_cnt values are from 0 to 63 */
  56         if (hop_cnt >= IB_SMP_MAX_PATH_HOPS)
  57                 return IB_SMI_DISCARD;
  58
  59         if (!ib_get_smp_direction(smp)) {
  60                 /* C14-9:1 */
  61                 if (hop_cnt && hop_ptr == 0) {
  62                         smp->hop_ptr++;
  63                         return (smp->initial_path[smp->hop_ptr] ==
  64                                 port_num ? IB_SMI_HANDLE : IB_SMI_DISCARD);
  65                 }
  66
  67                 /* C14-9:2 */
  68                 if (hop_ptr && hop_ptr < hop_cnt) {
  69                         if (node_type != RDMA_NODE_IB_SWITCH)
  70                                 return IB_SMI_DISCARD;
  71
  72                         /* smp->return_path set when received */
  73                         smp->hop_ptr++;
  74                         return (smp->initial_path[smp->hop_ptr] ==
  75                                 port_num ? IB_SMI_HANDLE : IB_SMI_DISCARD);
  76                 }
  77
  78                 /* C14-9:3 -- We're at the end of the DR segment of path */
  79                 if (hop_ptr == hop_cnt) {
  80                         /* smp->return_path set when received */
  81                         smp->hop_ptr++;
  82                         return (node_type == RDMA_NODE_IB_SWITCH ||
  83                                 smp->dr_dlid == IB_LID_PERMISSIVE ?
  84                                 IB_SMI_HANDLE : IB_SMI_DISCARD);
  85                 }
  86
  87                 /* C14-9:4 -- hop_ptr = hop_cnt + 1 -> give to SMA/SM */
  88                 /* C14-9:5 -- Fail unreasonable hop pointer */
  89                 return (hop_ptr == hop_cnt + 1 ? IB_SMI_HANDLE : IB_SMI_DISCARD);
  90
  91         } else {
  92                 /* C14-13:1 */
  93                 if (hop_cnt && hop_ptr == hop_cnt + 1) {
  94                         smp->hop_ptr--;
  95                         return (smp->return_path[smp->hop_ptr] ==
  96                                 port_num ? IB_SMI_HANDLE : IB_SMI_DISCARD);
  97                 }
  98
  99                 /* C14-13:2 */
 100                 if (2 <= hop_ptr && hop_ptr <= hop_cnt) {
 101                         if (node_type != RDMA_NODE_IB_SWITCH)
 102                                 return IB_SMI_DISCARD;
 103
 104                         smp->hop_ptr--;
 105                         return (smp->return_path[smp->hop_ptr] ==
 106                                 port_num ? IB_SMI_HANDLE : IB_SMI_DISCARD);
 107                 }
 108
 109                 /* C14-13:3 -- at the end of the DR segment of path */
 110                 if (hop_ptr == 1) {
 111                         smp->hop_ptr--;
 112                         /* C14-13:3 -- SMPs destined for SM shouldn't be here */
 113                         return (node_type == RDMA_NODE_IB_SWITCH ||
 114                                 smp->dr_slid == IB_LID_PERMISSIVE ?
 115                                 IB_SMI_HANDLE : IB_SMI_DISCARD);
 116                 }
 117
 118                 /* C14-13:4 -- hop_ptr = 0 -> should have gone to SM */
 119                 if (hop_ptr == 0)
 120                         return IB_SMI_HANDLE;
 121
 122                 /* C14-13:5 -- Check for unreasonable hop pointer */
 123                 return IB_SMI_DISCARD;
 124         }
 125 }
 126
 127 /*
 128  * Adjust information for a received SMP
 129  * Return 0 if the SMP should be dropped
 130  */
 131 enum smi_action smi_handle_dr_smp_recv(struct ib_smp *smp, u8 node_type,
 132                                        int port_num, int phys_port_cnt)
 133 {
 134         u8 hop_ptr, hop_cnt;
 135
 136         hop_ptr = smp->hop_ptr;
 137         hop_cnt = smp->hop_cnt;
 138
 139         /* See section 14.2.2.2, Vol 1 IB spec */
 140         /* C14-6 -- valid hop_cnt values are from 0 to 63 */
 141         if (hop_cnt >= IB_SMP_MAX_PATH_HOPS)
 142                 return IB_SMI_DISCARD;
 143
 144         if (!ib_get_smp_direction(smp)) {
 145                 /* C14-9:1 -- sender should have incremented hop_ptr */
 146                 if (hop_cnt && hop_ptr == 0)
 147                         return IB_SMI_DISCARD;
 148
 149                 /* C14-9:2 -- intermediate hop */
 150                 if (hop_ptr && hop_ptr < hop_cnt) {
 151                         if (node_type != RDMA_NODE_IB_SWITCH)
 152                                 return IB_SMI_DISCARD;
 153
 154                         smp->return_path[hop_ptr] = port_num;
 155                         /* smp->hop_ptr updated when sending */
 156                         return (smp->initial_path[hop_ptr+1] <= phys_port_cnt ?
 157                                 IB_SMI_HANDLE : IB_SMI_DISCARD);
 158                 }
 159
 160                 /* C14-9:3 -- We're at the end of the DR segment of path */
 161                 if (hop_ptr == hop_cnt) {
 162                         if (hop_cnt)
 163                                 smp->return_path[hop_ptr] = port_num;
 164                         /* smp->hop_ptr updated when sending */
 165
 166                         return (node_type == RDMA_NODE_IB_SWITCH ||
 167                                 smp->dr_dlid == IB_LID_PERMISSIVE ?
 168                                 IB_SMI_HANDLE : IB_SMI_DISCARD);
 169                 }
 170
 171                 /* C14-9:4 -- hop_ptr = hop_cnt + 1 -> give to SMA/SM */
 172                 /* C14-9:5 -- fail unreasonable hop pointer */
 173                 return (hop_ptr == hop_cnt + 1 ? IB_SMI_HANDLE : IB_SMI_DISCARD);
 174
 175         } else {
 176
 177                 /* C14-13:1 */
 178                 if (hop_cnt && hop_ptr == hop_cnt + 1) {
 179                         smp->hop_ptr--;
 180                         return (smp->return_path[smp->hop_ptr] ==
 181                                 port_num ? IB_SMI_HANDLE : IB_SMI_DISCARD);
 182                 }
 183
 184                 /* C14-13:2 */
 185                 if (2 <= hop_ptr && hop_ptr <= hop_cnt) {
 186                         if (node_type != RDMA_NODE_IB_SWITCH)
 187                                 return IB_SMI_DISCARD;
 188
 189                         /* smp->hop_ptr updated when sending */
 190                         return (smp->return_path[hop_ptr-1] <= phys_port_cnt ?
 191                                 IB_SMI_HANDLE : IB_SMI_DISCARD);
 192                 }
 193
 194                 /* C14-13:3 -- We're at the end of the DR segment of path */
 195                 if (hop_ptr == 1) {
 196                         if (smp->dr_slid == IB_LID_PERMISSIVE) {
 197                                 /* giving SMP to SM - update hop_ptr */
 198                                 smp->hop_ptr--;
 199                                 return IB_SMI_HANDLE;
 200                         }
 201                         /* smp->hop_ptr updated when sending */
 202                         return (node_type == RDMA_NODE_IB_SWITCH ?
 203                                 IB_SMI_HANDLE : IB_SMI_DISCARD);
 204                 }
 205
 206                 /* C14-13:4 -- hop_ptr = 0 -> give to SM */
 207                 /* C14-13:5 -- Check for unreasonable hop pointer */
 208                 return (hop_ptr == 0 ? IB_SMI_HANDLE : IB_SMI_DISCARD);
 209         }
 210 }
 211
 212 enum smi_forward_action smi_check_forward_dr_smp(struct ib_smp *smp)
 213 {
 214         u8 hop_ptr, hop_cnt;
 215
 216         hop_ptr = smp->hop_ptr;
 217         hop_cnt = smp->hop_cnt;
 218
 219         if (!ib_get_smp_direction(smp)) {
 220                 /* C14-9:2 -- intermediate hop */
 221                 if (hop_ptr && hop_ptr < hop_cnt)
 222                         return IB_SMI_FORWARD;
 223
 224                 /* C14-9:3 -- at the end of the DR segment of path */
 225                 if (hop_ptr == hop_cnt)
 226                         return (smp->dr_dlid == IB_LID_PERMISSIVE ?
 227                                 IB_SMI_SEND : IB_SMI_LOCAL);
 228
 229                 /* C14-9:4 -- hop_ptr = hop_cnt + 1 -> give to SMA/SM */
 230                 if (hop_ptr == hop_cnt + 1)
 231                         return IB_SMI_SEND;
 232         } else {
 233                 /* C14-13:2  -- intermediate hop */
 234                 if (2 <= hop_ptr && hop_ptr <= hop_cnt)
 235                         return IB_SMI_FORWARD;
 236
 237                 /* C14-13:3 -- at the end of the DR segment of path */
 238                 if (hop_ptr == 1)
 239                         return (smp->dr_slid != IB_LID_PERMISSIVE ?
 240                                 IB_SMI_SEND : IB_SMI_LOCAL);
 241         }
 242         return IB_SMI_LOCAL;
 243 }
 244
 245 /*
 246  * Return the forwarding port number from initial_path for outgoing SMP and
 247  * from return_path for returning SMP
 248  */
 249 int smi_get_fwd_port(struct ib_smp *smp)
 250 {
 251         return (!ib_get_smp_direction(smp) ? smp->initial_path[smp->hop_ptr+1] :
 252                 smp->return_path[smp->hop_ptr-1]);
 253 }