drivers/infiniband/hw/mlx4/cm.c

   1 /*
   2  * Copyright (c) 2012 Mellanox Technologies. All rights reserved.
   3  *
   4  * This software is available to you under a choice of one of two
   5  * licenses.  You may choose to be licensed under the terms of the GNU
   6  * General Public License (GPL) Version 2, available from the file
   7  * COPYING in the main directory of this source tree, or the
   8  * OpenIB.org BSD license below:
   9  *
  10  *     Redistribution and use in source and binary forms, with or
  11  *     without modification, are permitted provided that the following
  12  *     conditions are met:
  13  *
  14  *      - Redistributions of source code must retain the above
  15  *        copyright notice, this list of conditions and the following
  16  *        disclaimer.
  17  *
  18  *      - Redistributions in binary form must reproduce the above
  19  *        copyright notice, this list of conditions and the following
  20  *        disclaimer in the documentation and/or other materials
  21  *        provided with the distribution.
  22  *
  23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  24  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  25  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  26  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  27  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  28  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  29  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  30  * SOFTWARE.
  31  */
  32
  33 #include <rdma/ib_mad.h>
  34
  35 #include <linux/mlx4/cmd.h>
  36 #include <linux/rbtree.h>
  37 #include <linux/idr.h>
  38 #include <rdma/ib_cm.h>
  39
  40 #include "mlx4_ib.h"
  41
  42 #define CM_CLEANUP_CACHE_TIMEOUT  (5 * HZ)
  43
  44 struct id_map_entry {
  45         struct rb_node node;
  46
  47         u32 sl_cm_id;
  48         u32 pv_cm_id;
  49         int slave_id;
  50         int scheduled_delete;
  51         struct mlx4_ib_dev *dev;
  52
  53         struct list_head list;
  54         struct delayed_work timeout;
  55 };
  56
  57 struct cm_generic_msg {
  58         struct ib_mad_hdr hdr;
  59
  60         __be32 local_comm_id;
  61         __be32 remote_comm_id;
  62 };
  63
  64 struct cm_req_msg {
  65         unsigned char unused[0x60];
  66         union ib_gid primary_path_sgid;
  67 };
  68
  69
  70 static void set_local_comm_id(struct ib_mad *mad, u32 cm_id)
  71 {
  72         struct cm_generic_msg *msg = (struct cm_generic_msg *)mad;
  73         msg->local_comm_id = cpu_to_be32(cm_id);
  74 }
  75
  76 static u32 get_local_comm_id(struct ib_mad *mad)
  77 {
  78         struct cm_generic_msg *msg = (struct cm_generic_msg *)mad;
  79
  80         return be32_to_cpu(msg->local_comm_id);
  81 }
  82
  83 static void set_remote_comm_id(struct ib_mad *mad, u32 cm_id)
  84 {
  85         struct cm_generic_msg *msg = (struct cm_generic_msg *)mad;
  86         msg->remote_comm_id = cpu_to_be32(cm_id);
  87 }
  88
  89 static u32 get_remote_comm_id(struct ib_mad *mad)
  90 {
  91         struct cm_generic_msg *msg = (struct cm_generic_msg *)mad;
  92
  93         return be32_to_cpu(msg->remote_comm_id);
  94 }
  95
  96 static union ib_gid gid_from_req_msg(struct ib_device *ibdev, struct ib_mad *mad)
  97 {
  98         struct cm_req_msg *msg = (struct cm_req_msg *)mad;
  99
 100         return msg->primary_path_sgid;
 101 }
 102
 103 /* Lock should be taken before called */
 104 static struct id_map_entry *
 105 id_map_find_by_sl_id(struct ib_device *ibdev, u32 slave_id, u32 sl_cm_id)
 106 {
 107         struct rb_root *sl_id_map = &to_mdev(ibdev)->sriov.sl_id_map;
 108         struct rb_node *node = sl_id_map->rb_node;
 109
 110         while (node) {
 111                 struct id_map_entry *id_map_entry =
 112                         rb_entry(node, struct id_map_entry, node);
 113
 114                 if (id_map_entry->sl_cm_id > sl_cm_id)
 115                         node = node->rb_left;
 116                 else if (id_map_entry->sl_cm_id < sl_cm_id)
 117                         node = node->rb_right;
 118                 else if (id_map_entry->slave_id > slave_id)
 119                         node = node->rb_left;
 120                 else if (id_map_entry->slave_id < slave_id)
 121                         node = node->rb_right;
 122                 else
 123                         return id_map_entry;
 124         }
 125         return NULL;
 126 }
 127
 128 static void id_map_ent_timeout(struct work_struct *work)
 129 {
 130         struct delayed_work *delay = to_delayed_work(work);
 131         struct id_map_entry *ent = container_of(delay, struct id_map_entry, timeout);
 132         struct id_map_entry *db_ent, *found_ent;
 133         struct mlx4_ib_dev *dev = ent->dev;
 134         struct mlx4_ib_sriov *sriov = &dev->sriov;
 135         struct rb_root *sl_id_map = &sriov->sl_id_map;
 136         int pv_id = (int) ent->pv_cm_id;
 137
 138         spin_lock(&sriov->id_map_lock);
 139         db_ent = (struct id_map_entry *)idr_find(&sriov->pv_id_table, pv_id);
 140         if (!db_ent)
 141                 goto out;
 142         found_ent = id_map_find_by_sl_id(&dev->ib_dev, ent->slave_id, ent->sl_cm_id);
 143         if (found_ent && found_ent == ent)
 144                 rb_erase(&found_ent->node, sl_id_map);
 145         idr_remove(&sriov->pv_id_table, pv_id);
 146
 147 out:
 148         list_del(&ent->list);
 149         spin_unlock(&sriov->id_map_lock);
 150         kfree(ent);
 151 }
 152
 153 static void id_map_find_del(struct ib_device *ibdev, int pv_cm_id)
 154 {
 155         struct mlx4_ib_sriov *sriov = &to_mdev(ibdev)->sriov;
 156         struct rb_root *sl_id_map = &sriov->sl_id_map;
 157         struct id_map_entry *ent, *found_ent;
 158
 159         spin_lock(&sriov->id_map_lock);
 160         ent = (struct id_map_entry *)idr_find(&sriov->pv_id_table, pv_cm_id);
 161         if (!ent)
 162                 goto out;
 163         found_ent = id_map_find_by_sl_id(ibdev, ent->slave_id, ent->sl_cm_id);
 164         if (found_ent && found_ent == ent)
 165                 rb_erase(&found_ent->node, sl_id_map);
 166         idr_remove(&sriov->pv_id_table, pv_cm_id);
 167 out:
 168         spin_unlock(&sriov->id_map_lock);
 169 }
 170
 171 static void sl_id_map_add(struct ib_device *ibdev, struct id_map_entry *new)
 172 {
 173         struct rb_root *sl_id_map = &to_mdev(ibdev)->sriov.sl_id_map;
 174         struct rb_node **link = &sl_id_map->rb_node, *parent = NULL;
 175         struct id_map_entry *ent;
 176         int slave_id = new->slave_id;
 177         int sl_cm_id = new->sl_cm_id;
 178
 179         ent = id_map_find_by_sl_id(ibdev, slave_id, sl_cm_id);
 180         if (ent) {
 181                 pr_debug("overriding existing sl_id_map entry (cm_id = %x)\n",
 182                          sl_cm_id);
 183
 184                 rb_replace_node(&ent->node, &new->node, sl_id_map);
 185                 return;
 186         }
 187
 188         /* Go to the bottom of the tree */
 189         while (*link) {
 190                 parent = *link;
 191                 ent = rb_entry(parent, struct id_map_entry, node);
 192
 193                 if (ent->sl_cm_id > sl_cm_id || (ent->sl_cm_id == sl_cm_id && ent->slave_id > slave_id))
 194                         link = &(*link)->rb_left;
 195                 else
 196                         link = &(*link)->rb_right;
 197         }
 198
 199         rb_link_node(&new->node, parent, link);
 200         rb_insert_color(&new->node, sl_id_map);
 201 }
 202
 203 static struct id_map_entry *
 204 id_map_alloc(struct ib_device *ibdev, int slave_id, u32 sl_cm_id)
 205 {
 206         int ret;
 207         static int next_id;
 208         struct id_map_entry *ent;
 209         struct mlx4_ib_sriov *sriov = &to_mdev(ibdev)->sriov;
 210
 211         ent = kmalloc(sizeof (struct id_map_entry), GFP_KERNEL);
 212         if (!ent) {
 213                 mlx4_ib_warn(ibdev, "Couldn't allocate id cache entry - out of memory\n");
 214                 return ERR_PTR(-ENOMEM);
 215         }
 216
 217         ent->sl_cm_id = sl_cm_id;
 218         ent->slave_id = slave_id;
 219         ent->scheduled_delete = 0;
 220         ent->dev = to_mdev(ibdev);
 221         INIT_DELAYED_WORK(&ent->timeout, id_map_ent_timeout);
 222
 223         idr_preload(GFP_KERNEL);
 224         spin_lock(&to_mdev(ibdev)->sriov.id_map_lock);
 225
 226         ret = idr_alloc(&sriov->pv_id_table, ent, next_id, 0, GFP_NOWAIT);
 227         if (ret >= 0) {
 228                 next_id = max(ret + 1, 0);
 229                 ent->pv_cm_id = (u32)ret;
 230                 sl_id_map_add(ibdev, ent);
 231                 list_add_tail(&ent->list, &sriov->cm_list);
 232         }
 233
 234         spin_unlock(&sriov->id_map_lock);
 235         idr_preload_end();
 236
 237         if (ret >= 0)
 238                 return ent;
 239
 240         /*error flow*/
 241         kfree(ent);
 242         mlx4_ib_warn(ibdev, "No more space in the idr (err:0x%x)\n", ret);
 243         return ERR_PTR(-ENOMEM);
 244 }
 245
 246 static struct id_map_entry *
 247 id_map_get(struct ib_device *ibdev, int *pv_cm_id, int sl_cm_id, int slave_id)
 248 {
 249         struct id_map_entry *ent;
 250         struct mlx4_ib_sriov *sriov = &to_mdev(ibdev)->sriov;
 251
 252         spin_lock(&sriov->id_map_lock);
 253         if (*pv_cm_id == -1) {
 254                 ent = id_map_find_by_sl_id(ibdev, sl_cm_id, slave_id);
 255                 if (ent)
 256                         *pv_cm_id = (int) ent->pv_cm_id;
 257         } else
 258                 ent = (struct id_map_entry *)idr_find(&sriov->pv_id_table, *pv_cm_id);
 259         spin_unlock(&sriov->id_map_lock);
 260
 261         return ent;
 262 }
 263
 264 static void schedule_delayed(struct ib_device *ibdev, struct id_map_entry *id)
 265 {
 266         struct mlx4_ib_sriov *sriov = &to_mdev(ibdev)->sriov;
 267         unsigned long flags;
 268
 269         spin_lock(&sriov->id_map_lock);
 270         spin_lock_irqsave(&sriov->going_down_lock, flags);
 271         /*make sure that there is no schedule inside the scheduled work.*/
 272         if (!sriov->is_going_down) {
 273                 id->scheduled_delete = 1;
 274                 schedule_delayed_work(&id->timeout, CM_CLEANUP_CACHE_TIMEOUT);
 275         }
 276         spin_unlock_irqrestore(&sriov->going_down_lock, flags);
 277         spin_unlock(&sriov->id_map_lock);
 278 }
 279
 280 int mlx4_ib_multiplex_cm_handler(struct ib_device *ibdev, int port, int slave_id,
 281                 struct ib_mad *mad)
 282 {
 283         struct id_map_entry *id;
 284         u32 sl_cm_id;
 285         int pv_cm_id = -1;
 286
 287         sl_cm_id = get_local_comm_id(mad);
 288
 289         if (mad->mad_hdr.attr_id == CM_REQ_ATTR_ID ||
 290                         mad->mad_hdr.attr_id == CM_REP_ATTR_ID) {
 291                 id = id_map_alloc(ibdev, slave_id, sl_cm_id);
 292                 if (IS_ERR(id)) {
 293                         mlx4_ib_warn(ibdev, "%s: id{slave: %d, sl_cm_id: 0x%x} Failed to id_map_alloc\n",
 294                                 __func__, slave_id, sl_cm_id);
 295                         return PTR_ERR(id);
 296                 }
 297         } else if (mad->mad_hdr.attr_id == CM_REJ_ATTR_ID) {
 298                 return 0;
 299         } else {
 300                 id = id_map_get(ibdev, &pv_cm_id, slave_id, sl_cm_id);
 301         }
 302
 303         if (!id) {
 304                 pr_debug("id{slave: %d, sl_cm_id: 0x%x} is NULL!\n",
 305                          slave_id, sl_cm_id);
 306                 return -EINVAL;
 307         }
 308
 309         set_local_comm_id(mad, id->pv_cm_id);
 310
 311         if (mad->mad_hdr.attr_id == CM_DREQ_ATTR_ID)
 312                 schedule_delayed(ibdev, id);
 313         else if (mad->mad_hdr.attr_id == CM_DREP_ATTR_ID)
 314                 id_map_find_del(ibdev, pv_cm_id);
 315
 316         return 0;
 317 }
 318
 319 int mlx4_ib_demux_cm_handler(struct ib_device *ibdev, int port, int *slave,
 320                                                              struct ib_mad *mad)
 321 {
 322         u32 pv_cm_id;
 323         struct id_map_entry *id;
 324
 325         if (mad->mad_hdr.attr_id == CM_REQ_ATTR_ID) {
 326                 union ib_gid gid;
 327
 328                 gid = gid_from_req_msg(ibdev, mad);
 329                 *slave = mlx4_ib_find_real_gid(ibdev, port, gid.global.interface_id);
 330                 if (*slave < 0) {
 331                         mlx4_ib_warn(ibdev, "failed matching slave_id by gid (0x%llx)\n",
 332                                         gid.global.interface_id);
 333                         return -ENOENT;
 334                 }
 335                 return 0;
 336         }
 337
 338         pv_cm_id = get_remote_comm_id(mad);
 339         id = id_map_get(ibdev, (int *)&pv_cm_id, -1, -1);
 340
 341         if (!id) {
 342                 pr_debug("Couldn't find an entry for pv_cm_id 0x%x\n", pv_cm_id);
 343                 return -ENOENT;
 344         }
 345
 346         *slave = id->slave_id;
 347         set_remote_comm_id(mad, id->sl_cm_id);
 348
 349         if (mad->mad_hdr.attr_id == CM_DREQ_ATTR_ID)
 350                 schedule_delayed(ibdev, id);
 351         else if (mad->mad_hdr.attr_id == CM_REJ_ATTR_ID ||
 352                         mad->mad_hdr.attr_id == CM_DREP_ATTR_ID) {
 353                 id_map_find_del(ibdev, (int) pv_cm_id);
 354         }
 355
 356         return 0;
 357 }
 358
 359 void mlx4_ib_cm_paravirt_init(struct mlx4_ib_dev *dev)
 360 {
 361         spin_lock_init(&dev->sriov.id_map_lock);
 362         INIT_LIST_HEAD(&dev->sriov.cm_list);
 363         dev->sriov.sl_id_map = RB_ROOT;
 364         idr_init(&dev->sriov.pv_id_table);
 365 }
 366
 367 /* slave = -1 ==> all slaves */
 368 /* TBD -- call paravirt clean for single slave.  Need for slave RESET event */
 369 void mlx4_ib_cm_paravirt_clean(struct mlx4_ib_dev *dev, int slave)
 370 {
 371         struct mlx4_ib_sriov *sriov = &dev->sriov;
 372         struct rb_root *sl_id_map = &sriov->sl_id_map;
 373         struct list_head lh;
 374         struct rb_node *nd;
 375         int need_flush = 1;
 376         struct id_map_entry *map, *tmp_map;
 377         /* cancel all delayed work queue entries */
 378         INIT_LIST_HEAD(&lh);
 379         spin_lock(&sriov->id_map_lock);
 380         list_for_each_entry_safe(map, tmp_map, &dev->sriov.cm_list, list) {
 381                 if (slave < 0 || slave == map->slave_id) {
 382                         if (map->scheduled_delete)
 383                                 need_flush &= !!cancel_delayed_work(&map->timeout);
 384                 }
 385         }
 386
 387         spin_unlock(&sriov->id_map_lock);
 388
 389         if (!need_flush)
 390                 flush_scheduled_work(); /* make sure all timers were flushed */
 391
 392         /* now, remove all leftover entries from databases*/
 393         spin_lock(&sriov->id_map_lock);
 394         if (slave < 0) {
 395                 while (rb_first(sl_id_map)) {
 396                         struct id_map_entry *ent =
 397                                 rb_entry(rb_first(sl_id_map),
 398                                          struct id_map_entry, node);
 399
 400                         rb_erase(&ent->node, sl_id_map);
 401                         idr_remove(&sriov->pv_id_table, (int) ent->pv_cm_id);
 402                 }
 403                 list_splice_init(&dev->sriov.cm_list, &lh);
 404         } else {
 405                 /* first, move nodes belonging to slave to db remove list */
 406                 nd = rb_first(sl_id_map);
 407                 while (nd) {
 408                         struct id_map_entry *ent =
 409                                 rb_entry(nd, struct id_map_entry, node);
 410                         nd = rb_next(nd);
 411                         if (ent->slave_id == slave)
 412                                 list_move_tail(&ent->list, &lh);
 413                 }
 414                 /* remove those nodes from databases */
 415                 list_for_each_entry_safe(map, tmp_map, &lh, list) {
 416                         rb_erase(&map->node, sl_id_map);
 417                         idr_remove(&sriov->pv_id_table, (int) map->pv_cm_id);
 418                 }
 419
 420                 /* add remaining nodes from cm_list */
 421                 list_for_each_entry_safe(map, tmp_map, &dev->sriov.cm_list, list) {
 422                         if (slave == map->slave_id)
 423                                 list_move_tail(&map->list, &lh);
 424                 }
 425         }
 426
 427         spin_unlock(&sriov->id_map_lock);
 428
 429         /* free any map entries left behind due to cancel_delayed_work above */
 430         list_for_each_entry_safe(map, tmp_map, &lh, list) {
 431                 list_del(&map->list);
 432                 kfree(map);
 433         }
 434 }