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, id;
 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         do {
 224                 spin_lock(&to_mdev(ibdev)->sriov.id_map_lock);
 225                 ret = idr_get_new_above(&sriov->pv_id_table, ent,
 226                                         next_id, &id);
 227                 if (!ret) {
 228                         next_id = ((unsigned) id + 1) & MAX_IDR_MASK;
 229                         ent->pv_cm_id = (u32)id;
 230                         sl_id_map_add(ibdev, ent);
 231                 }
 232
 233                 spin_unlock(&sriov->id_map_lock);
 234         } while (ret == -EAGAIN && idr_pre_get(&sriov->pv_id_table, GFP_KERNEL));
 235         /*the function idr_get_new_above can return -ENOSPC, so don't insert in that case.*/
 236         if (!ret) {
 237                 spin_lock(&sriov->id_map_lock);
 238                 list_add_tail(&ent->list, &sriov->cm_list);
 239                 spin_unlock(&sriov->id_map_lock);
 240                 return ent;
 241         }
 242         /*error flow*/
 243         kfree(ent);
 244         mlx4_ib_warn(ibdev, "No more space in the idr (err:0x%x)\n", ret);
 245         return ERR_PTR(-ENOMEM);
 246 }
 247
 248 static struct id_map_entry *
 249 id_map_get(struct ib_device *ibdev, int *pv_cm_id, int sl_cm_id, int slave_id)
 250 {
 251         struct id_map_entry *ent;
 252         struct mlx4_ib_sriov *sriov = &to_mdev(ibdev)->sriov;
 253
 254         spin_lock(&sriov->id_map_lock);
 255         if (*pv_cm_id == -1) {
 256                 ent = id_map_find_by_sl_id(ibdev, sl_cm_id, slave_id);
 257                 if (ent)
 258                         *pv_cm_id = (int) ent->pv_cm_id;
 259         } else
 260                 ent = (struct id_map_entry *)idr_find(&sriov->pv_id_table, *pv_cm_id);
 261         spin_unlock(&sriov->id_map_lock);
 262
 263         return ent;
 264 }
 265
 266 static void schedule_delayed(struct ib_device *ibdev, struct id_map_entry *id)
 267 {
 268         struct mlx4_ib_sriov *sriov = &to_mdev(ibdev)->sriov;
 269         unsigned long flags;
 270
 271         spin_lock(&sriov->id_map_lock);
 272         spin_lock_irqsave(&sriov->going_down_lock, flags);
 273         /*make sure that there is no schedule inside the scheduled work.*/
 274         if (!sriov->is_going_down) {
 275                 id->scheduled_delete = 1;
 276                 schedule_delayed_work(&id->timeout, CM_CLEANUP_CACHE_TIMEOUT);
 277         }
 278         spin_unlock_irqrestore(&sriov->going_down_lock, flags);
 279         spin_unlock(&sriov->id_map_lock);
 280 }
 281
 282 int mlx4_ib_multiplex_cm_handler(struct ib_device *ibdev, int port, int slave_id,
 283                 struct ib_mad *mad)
 284 {
 285         struct id_map_entry *id;
 286         u32 sl_cm_id;
 287         int pv_cm_id = -1;
 288
 289         sl_cm_id = get_local_comm_id(mad);
 290
 291         if (mad->mad_hdr.attr_id == CM_REQ_ATTR_ID ||
 292                         mad->mad_hdr.attr_id == CM_REP_ATTR_ID) {
 293                 id = id_map_alloc(ibdev, slave_id, sl_cm_id);
 294                 if (IS_ERR(id)) {
 295                         mlx4_ib_warn(ibdev, "%s: id{slave: %d, sl_cm_id: 0x%x} Failed to id_map_alloc\n",
 296                                 __func__, slave_id, sl_cm_id);
 297                         return PTR_ERR(id);
 298                 }
 299         } else if (mad->mad_hdr.attr_id == CM_REJ_ATTR_ID) {
 300                 return 0;
 301         } else {
 302                 id = id_map_get(ibdev, &pv_cm_id, slave_id, sl_cm_id);
 303         }
 304
 305         if (!id) {
 306                 pr_debug("id{slave: %d, sl_cm_id: 0x%x} is NULL!\n",
 307                          slave_id, sl_cm_id);
 308                 return -EINVAL;
 309         }
 310
 311         set_local_comm_id(mad, id->pv_cm_id);
 312
 313         if (mad->mad_hdr.attr_id == CM_DREQ_ATTR_ID)
 314                 schedule_delayed(ibdev, id);
 315         else if (mad->mad_hdr.attr_id == CM_DREP_ATTR_ID)
 316                 id_map_find_del(ibdev, pv_cm_id);
 317
 318         return 0;
 319 }
 320
 321 int mlx4_ib_demux_cm_handler(struct ib_device *ibdev, int port, int *slave,
 322                                                              struct ib_mad *mad)
 323 {
 324         u32 pv_cm_id;
 325         struct id_map_entry *id;
 326
 327         if (mad->mad_hdr.attr_id == CM_REQ_ATTR_ID) {
 328                 union ib_gid gid;
 329
 330                 gid = gid_from_req_msg(ibdev, mad);
 331                 *slave = mlx4_ib_find_real_gid(ibdev, port, gid.global.interface_id);
 332                 if (*slave < 0) {
 333                         mlx4_ib_warn(ibdev, "failed matching slave_id by gid (0x%llx)\n",
 334                                         gid.global.interface_id);
 335                         return -ENOENT;
 336                 }
 337                 return 0;
 338         }
 339
 340         pv_cm_id = get_remote_comm_id(mad);
 341         id = id_map_get(ibdev, (int *)&pv_cm_id, -1, -1);
 342
 343         if (!id) {
 344                 pr_debug("Couldn't find an entry for pv_cm_id 0x%x\n", pv_cm_id);
 345                 return -ENOENT;
 346         }
 347
 348         *slave = id->slave_id;
 349         set_remote_comm_id(mad, id->sl_cm_id);
 350
 351         if (mad->mad_hdr.attr_id == CM_DREQ_ATTR_ID)
 352                 schedule_delayed(ibdev, id);
 353         else if (mad->mad_hdr.attr_id == CM_REJ_ATTR_ID ||
 354                         mad->mad_hdr.attr_id == CM_DREP_ATTR_ID) {
 355                 id_map_find_del(ibdev, (int) pv_cm_id);
 356         }
 357
 358         return 0;
 359 }
 360
 361 void mlx4_ib_cm_paravirt_init(struct mlx4_ib_dev *dev)
 362 {
 363         spin_lock_init(&dev->sriov.id_map_lock);
 364         INIT_LIST_HEAD(&dev->sriov.cm_list);
 365         dev->sriov.sl_id_map = RB_ROOT;
 366         idr_init(&dev->sriov.pv_id_table);
 367         idr_pre_get(&dev->sriov.pv_id_table, GFP_KERNEL);
 368 }
 369
 370 /* slave = -1 ==> all slaves */
 371 /* TBD -- call paravirt clean for single slave.  Need for slave RESET event */
 372 void mlx4_ib_cm_paravirt_clean(struct mlx4_ib_dev *dev, int slave)
 373 {
 374         struct mlx4_ib_sriov *sriov = &dev->sriov;
 375         struct rb_root *sl_id_map = &sriov->sl_id_map;
 376         struct list_head lh;
 377         struct rb_node *nd;
 378         int need_flush = 1;
 379         struct id_map_entry *map, *tmp_map;
 380         /* cancel all delayed work queue entries */
 381         INIT_LIST_HEAD(&lh);
 382         spin_lock(&sriov->id_map_lock);
 383         list_for_each_entry_safe(map, tmp_map, &dev->sriov.cm_list, list) {
 384                 if (slave < 0 || slave == map->slave_id) {
 385                         if (map->scheduled_delete)
 386                                 need_flush &= !!cancel_delayed_work(&map->timeout);
 387                 }
 388         }
 389
 390         spin_unlock(&sriov->id_map_lock);
 391
 392         if (!need_flush)
 393                 flush_scheduled_work(); /* make sure all timers were flushed */
 394
 395         /* now, remove all leftover entries from databases*/
 396         spin_lock(&sriov->id_map_lock);
 397         if (slave < 0) {
 398                 while (rb_first(sl_id_map)) {
 399                         struct id_map_entry *ent =
 400                                 rb_entry(rb_first(sl_id_map),
 401                                          struct id_map_entry, node);
 402
 403                         rb_erase(&ent->node, sl_id_map);
 404                         idr_remove(&sriov->pv_id_table, (int) ent->pv_cm_id);
 405                 }
 406                 list_splice_init(&dev->sriov.cm_list, &lh);
 407         } else {
 408                 /* first, move nodes belonging to slave to db remove list */
 409                 nd = rb_first(sl_id_map);
 410                 while (nd) {
 411                         struct id_map_entry *ent =
 412                                 rb_entry(nd, struct id_map_entry, node);
 413                         nd = rb_next(nd);
 414                         if (ent->slave_id == slave)
 415                                 list_move_tail(&ent->list, &lh);
 416                 }
 417                 /* remove those nodes from databases */
 418                 list_for_each_entry_safe(map, tmp_map, &lh, list) {
 419                         rb_erase(&map->node, sl_id_map);
 420                         idr_remove(&sriov->pv_id_table, (int) map->pv_cm_id);
 421                 }
 422
 423                 /* add remaining nodes from cm_list */
 424                 list_for_each_entry_safe(map, tmp_map, &dev->sriov.cm_list, list) {
 425                         if (slave == map->slave_id)
 426                                 list_move_tail(&map->list, &lh);
 427                 }
 428         }
 429
 430         spin_unlock(&sriov->id_map_lock);
 431
 432         /* free any map entries left behind due to cancel_delayed_work above */
 433         list_for_each_entry_safe(map, tmp_map, &lh, list) {
 434                 list_del(&map->list);
 435                 kfree(map);
 436         }
 437 }