2 * Copyright (C) 2009 Michael Brown <mbrown@fensystems.co.uk>.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License as
6 * published by the Free Software Foundation; either version 2 of the
7 * License, or any later version.
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
19 * You can also choose to distribute this program under the terms of
20 * the Unmodified Binary Distribution Licence (as given in the file
21 * COPYING.UBDL), provided that you have satisfied its requirements.
24 FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
31 #include <ipxe/infiniband.h>
32 #include <ipxe/ib_mi.h>
33 #include <ipxe/ib_pathrec.h>
37 * Infiniband path lookups
42 * Handle path transaction completion
44 * @v ibdev Infiniband device
45 * @v mi Management interface
46 * @v madx Management transaction
48 * @v mad Received MAD (or NULL on error)
49 * @v av Source address vector (or NULL on error)
51 static void ib_path_complete ( struct ib_device *ibdev,
52 struct ib_mad_interface *mi,
53 struct ib_mad_transaction *madx,
54 int rc, union ib_mad *mad,
55 struct ib_address_vector *av __unused ) {
56 struct ib_path *path = ib_madx_get_ownerdata ( madx );
57 union ib_gid *dgid = &path->av.gid;
58 struct ib_path_record *pathrec = &mad->sa.sa_data.path_record;
61 if ( ( rc == 0 ) && ( mad->hdr.status != htons ( IB_MGMT_STATUS_OK ) ))
64 DBGC ( ibdev, "IBDEV %p path lookup for " IB_GID_FMT
66 ibdev, IB_GID_ARGS ( dgid ), strerror ( rc ) );
70 /* Extract values from MAD */
71 path->av.lid = ntohs ( pathrec->dlid );
72 path->av.sl = ( pathrec->reserved__sl & 0x0f );
73 path->av.rate = ( pathrec->rate_selector__rate & 0x3f );
74 DBGC ( ibdev, "IBDEV %p path to " IB_GID_FMT " is %04x sl %d rate "
75 "%d\n", ibdev, IB_GID_ARGS ( dgid ), path->av.lid, path->av.sl,
79 /* Destroy the completed transaction */
80 ib_destroy_madx ( ibdev, mi, madx );
83 /* Hand off to upper completion handler */
84 path->op->complete ( ibdev, path, rc, &path->av );
87 /** Path transaction completion operations */
88 static struct ib_mad_transaction_operations ib_path_op = {
89 .complete = ib_path_complete,
95 * @v ibdev Infiniband device
96 * @v av Address vector to complete
97 * @v op Path operations
101 ib_create_path ( struct ib_device *ibdev, struct ib_address_vector *av,
102 struct ib_path_operations *op ) {
103 struct ib_path *path;
105 struct ib_mad_sa *sa = &mad.sa;
107 /* Allocate and initialise structure */
108 path = zalloc ( sizeof ( *path ) );
112 memcpy ( &path->av, av, sizeof ( path->av ) );
115 /* Construct path request */
116 memset ( sa, 0, sizeof ( *sa ) );
117 sa->mad_hdr.mgmt_class = IB_MGMT_CLASS_SUBN_ADM;
118 sa->mad_hdr.class_version = IB_SA_CLASS_VERSION;
119 sa->mad_hdr.method = IB_MGMT_METHOD_GET;
120 sa->mad_hdr.attr_id = htons ( IB_SA_ATTR_PATH_REC );
121 sa->sa_hdr.comp_mask[1] =
122 htonl ( IB_SA_PATH_REC_DGID | IB_SA_PATH_REC_SGID );
123 memcpy ( &sa->sa_data.path_record.dgid, &path->av.gid,
124 sizeof ( sa->sa_data.path_record.dgid ) );
125 memcpy ( &sa->sa_data.path_record.sgid, &ibdev->gid,
126 sizeof ( sa->sa_data.path_record.sgid ) );
128 /* Create management transaction */
129 path->madx = ib_create_madx ( ibdev, ibdev->gsi, &mad, NULL,
132 goto err_create_madx;
133 ib_madx_set_ownerdata ( path->madx, path );
137 ib_destroy_madx ( ibdev, ibdev->gsi, path->madx );
147 * @v ibdev Infiniband device
150 void ib_destroy_path ( struct ib_device *ibdev, struct ib_path *path ) {
153 ib_destroy_madx ( ibdev, ibdev->gsi, path->madx );
157 /** Number of path cache entries
159 * Must be a power of two.
161 #define IB_NUM_CACHED_PATHS 4
164 struct ib_cached_path {
166 struct ib_path *path;
170 static struct ib_cached_path ib_path_cache[IB_NUM_CACHED_PATHS];
172 /** Oldest path cache entry index */
173 static unsigned int ib_path_cache_idx;
176 * Find path cache entry
178 * @v ibdev Infiniband device
179 * @v dgid Destination GID
180 * @ret path Path cache entry, or NULL
182 static struct ib_cached_path *
183 ib_find_path_cache_entry ( struct ib_device *ibdev, union ib_gid *dgid ) {
184 struct ib_cached_path *cached;
187 for ( i = 0 ; i < IB_NUM_CACHED_PATHS ; i++ ) {
188 cached = &ib_path_cache[i];
189 if ( ! cached->path )
191 if ( cached->path->ibdev != ibdev )
193 if ( memcmp ( &cached->path->av.gid, dgid,
194 sizeof ( cached->path->av.gid ) ) != 0 )
203 * Handle cached path transaction completion
205 * @v ibdev Infiniband device
208 * @v av Address vector, or NULL on error
210 static void ib_cached_path_complete ( struct ib_device *ibdev,
211 struct ib_path *path, int rc,
212 struct ib_address_vector *av __unused ) {
213 struct ib_cached_path *cached = ib_path_get_ownerdata ( path );
215 /* If the transaction failed, erase the cache entry */
217 /* Destroy the old cache entry */
218 ib_destroy_path ( ibdev, path );
219 memset ( cached, 0, sizeof ( *cached ) );
223 /* Do not destroy the completed transaction; we still need to
224 * refer to the resolved path.
228 /** Cached path transaction completion operations */
229 static struct ib_path_operations ib_cached_path_op = {
230 .complete = ib_cached_path_complete,
236 * @v ibdev Infiniband device
237 * @v av Address vector to complete
238 * @ret rc Return status code
240 * This provides a non-transactional way to resolve a path, via a
241 * cache similar to ARP.
243 int ib_resolve_path ( struct ib_device *ibdev, struct ib_address_vector *av ) {
244 union ib_gid *gid = &av->gid;
245 struct ib_cached_path *cached;
246 unsigned int cache_idx;
249 if ( ! av->gid_present ) {
250 DBGC ( ibdev, "IBDEV %p attempt to look up path without GID\n",
255 /* Look in cache for a matching entry */
256 cached = ib_find_path_cache_entry ( ibdev, gid );
257 if ( cached && cached->path->av.lid ) {
258 /* Populated entry found */
259 av->lid = cached->path->av.lid;
260 av->rate = cached->path->av.rate;
261 av->sl = cached->path->av.sl;
262 DBGC2 ( ibdev, "IBDEV %p cache hit for " IB_GID_FMT "\n",
263 ibdev, IB_GID_ARGS ( gid ) );
266 DBGC ( ibdev, "IBDEV %p cache miss for " IB_GID_FMT "%s\n", ibdev,
267 IB_GID_ARGS ( gid ), ( cached ? " (in progress)" : "" ) );
269 /* If lookup is already in progress, do nothing */
273 /* Locate a new cache entry to use */
274 cache_idx = ( (ib_path_cache_idx++) % IB_NUM_CACHED_PATHS );
275 cached = &ib_path_cache[cache_idx];
277 /* Destroy the old cache entry */
279 ib_destroy_path ( ibdev, cached->path );
280 memset ( cached, 0, sizeof ( *cached ) );
282 /* Create new path */
283 cached->path = ib_create_path ( ibdev, av, &ib_cached_path_op );
284 if ( ! cached->path ) {
285 DBGC ( ibdev, "IBDEV %p could not create path\n",
289 ib_path_set_ownerdata ( cached->path, cached );