drivers/net/ethernet/qlogic/qede/qede_rdma.c

   1 /* QLogic qedr NIC Driver
   2  * Copyright (c) 2015-2017  QLogic Corporation
   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 #include <linux/pci.h>
  33 #include <linux/netdevice.h>
  34 #include <linux/list.h>
  35 #include <linux/mutex.h>
  36 #include <linux/qed/qede_rdma.h>
  37 #include "qede.h"
  38
  39 static struct qedr_driver *qedr_drv;
  40 static LIST_HEAD(qedr_dev_list);
  41 static DEFINE_MUTEX(qedr_dev_list_lock);
  42
  43 bool qede_rdma_supported(struct qede_dev *dev)
  44 {
  45         return dev->dev_info.common.rdma_supported;
  46 }
  47
  48 static void _qede_rdma_dev_add(struct qede_dev *edev)
  49 {
  50         if (!qedr_drv)
  51                 return;
  52
  53         edev->rdma_info.qedr_dev = qedr_drv->add(edev->cdev, edev->pdev,
  54                                                  edev->ndev);
  55 }
  56
  57 static int qede_rdma_create_wq(struct qede_dev *edev)
  58 {
  59         INIT_LIST_HEAD(&edev->rdma_info.rdma_event_list);
  60         kref_init(&edev->rdma_info.refcnt);
  61         init_completion(&edev->rdma_info.event_comp);
  62
  63         edev->rdma_info.rdma_wq = create_singlethread_workqueue("rdma_wq");
  64         if (!edev->rdma_info.rdma_wq) {
  65                 DP_NOTICE(edev, "qedr: Could not create workqueue\n");
  66                 return -ENOMEM;
  67         }
  68
  69         return 0;
  70 }
  71
  72 static void qede_rdma_cleanup_event(struct qede_dev *edev)
  73 {
  74         struct list_head *head = &edev->rdma_info.rdma_event_list;
  75         struct qede_rdma_event_work *event_node;
  76
  77         flush_workqueue(edev->rdma_info.rdma_wq);
  78         while (!list_empty(head)) {
  79                 event_node = list_entry(head->next, struct qede_rdma_event_work,
  80                                         list);
  81                 cancel_work_sync(&event_node->work);
  82                 list_del(&event_node->list);
  83                 kfree(event_node);
  84         }
  85 }
  86
  87 static void qede_rdma_complete_event(struct kref *ref)
  88 {
  89         struct qede_rdma_dev *rdma_dev =
  90                 container_of(ref, struct qede_rdma_dev, refcnt);
  91
  92         /* no more events will be added after this */
  93         complete(&rdma_dev->event_comp);
  94 }
  95
  96 static void qede_rdma_destroy_wq(struct qede_dev *edev)
  97 {
  98         /* Avoid race with add_event flow, make sure it finishes before
  99          * we start accessing the list and cleaning up the work
 100          */
 101         kref_put(&edev->rdma_info.refcnt, qede_rdma_complete_event);
 102         wait_for_completion(&edev->rdma_info.event_comp);
 103
 104         qede_rdma_cleanup_event(edev);
 105         destroy_workqueue(edev->rdma_info.rdma_wq);
 106 }
 107
 108 int qede_rdma_dev_add(struct qede_dev *edev)
 109 {
 110         int rc = 0;
 111
 112         if (qede_rdma_supported(edev)) {
 113                 rc = qede_rdma_create_wq(edev);
 114                 if (rc)
 115                         return rc;
 116
 117                 INIT_LIST_HEAD(&edev->rdma_info.entry);
 118                 mutex_lock(&qedr_dev_list_lock);
 119                 list_add_tail(&edev->rdma_info.entry, &qedr_dev_list);
 120                 _qede_rdma_dev_add(edev);
 121                 mutex_unlock(&qedr_dev_list_lock);
 122         }
 123
 124         return rc;
 125 }
 126
 127 static void _qede_rdma_dev_remove(struct qede_dev *edev)
 128 {
 129         if (qedr_drv && qedr_drv->remove && edev->rdma_info.qedr_dev)
 130                 qedr_drv->remove(edev->rdma_info.qedr_dev);
 131         edev->rdma_info.qedr_dev = NULL;
 132 }
 133
 134 void qede_rdma_dev_remove(struct qede_dev *edev)
 135 {
 136         if (!qede_rdma_supported(edev))
 137                 return;
 138
 139         qede_rdma_destroy_wq(edev);
 140         mutex_lock(&qedr_dev_list_lock);
 141         _qede_rdma_dev_remove(edev);
 142         list_del(&edev->rdma_info.entry);
 143         mutex_unlock(&qedr_dev_list_lock);
 144 }
 145
 146 static void _qede_rdma_dev_open(struct qede_dev *edev)
 147 {
 148         if (qedr_drv && edev->rdma_info.qedr_dev && qedr_drv->notify)
 149                 qedr_drv->notify(edev->rdma_info.qedr_dev, QEDE_UP);
 150 }
 151
 152 static void qede_rdma_dev_open(struct qede_dev *edev)
 153 {
 154         if (!qede_rdma_supported(edev))
 155                 return;
 156
 157         mutex_lock(&qedr_dev_list_lock);
 158         _qede_rdma_dev_open(edev);
 159         mutex_unlock(&qedr_dev_list_lock);
 160 }
 161
 162 static void _qede_rdma_dev_close(struct qede_dev *edev)
 163 {
 164         if (qedr_drv && edev->rdma_info.qedr_dev && qedr_drv->notify)
 165                 qedr_drv->notify(edev->rdma_info.qedr_dev, QEDE_DOWN);
 166 }
 167
 168 static void qede_rdma_dev_close(struct qede_dev *edev)
 169 {
 170         if (!qede_rdma_supported(edev))
 171                 return;
 172
 173         mutex_lock(&qedr_dev_list_lock);
 174         _qede_rdma_dev_close(edev);
 175         mutex_unlock(&qedr_dev_list_lock);
 176 }
 177
 178 static void qede_rdma_dev_shutdown(struct qede_dev *edev)
 179 {
 180         if (!qede_rdma_supported(edev))
 181                 return;
 182
 183         mutex_lock(&qedr_dev_list_lock);
 184         if (qedr_drv && edev->rdma_info.qedr_dev && qedr_drv->notify)
 185                 qedr_drv->notify(edev->rdma_info.qedr_dev, QEDE_CLOSE);
 186         mutex_unlock(&qedr_dev_list_lock);
 187 }
 188
 189 int qede_rdma_register_driver(struct qedr_driver *drv)
 190 {
 191         struct qede_dev *edev;
 192         u8 qedr_counter = 0;
 193
 194         mutex_lock(&qedr_dev_list_lock);
 195         if (qedr_drv) {
 196                 mutex_unlock(&qedr_dev_list_lock);
 197                 return -EINVAL;
 198         }
 199         qedr_drv = drv;
 200
 201         list_for_each_entry(edev, &qedr_dev_list, rdma_info.entry) {
 202                 struct net_device *ndev;
 203
 204                 qedr_counter++;
 205                 _qede_rdma_dev_add(edev);
 206                 ndev = edev->ndev;
 207                 if (netif_running(ndev) && netif_oper_up(ndev))
 208                         _qede_rdma_dev_open(edev);
 209         }
 210         mutex_unlock(&qedr_dev_list_lock);
 211
 212         pr_notice("qedr: discovered and registered %d RDMA funcs\n",
 213                   qedr_counter);
 214
 215         return 0;
 216 }
 217 EXPORT_SYMBOL(qede_rdma_register_driver);
 218
 219 void qede_rdma_unregister_driver(struct qedr_driver *drv)
 220 {
 221         struct qede_dev *edev;
 222
 223         mutex_lock(&qedr_dev_list_lock);
 224         list_for_each_entry(edev, &qedr_dev_list, rdma_info.entry) {
 225                 if (edev->rdma_info.qedr_dev)
 226                         _qede_rdma_dev_remove(edev);
 227         }
 228         qedr_drv = NULL;
 229         mutex_unlock(&qedr_dev_list_lock);
 230 }
 231 EXPORT_SYMBOL(qede_rdma_unregister_driver);
 232
 233 static void qede_rdma_changeaddr(struct qede_dev *edev)
 234 {
 235         if (!qede_rdma_supported(edev))
 236                 return;
 237
 238         if (qedr_drv && edev->rdma_info.qedr_dev && qedr_drv->notify)
 239                 qedr_drv->notify(edev->rdma_info.qedr_dev, QEDE_CHANGE_ADDR);
 240 }
 241
 242 static struct qede_rdma_event_work *
 243 qede_rdma_get_free_event_node(struct qede_dev *edev)
 244 {
 245         struct qede_rdma_event_work *event_node = NULL;
 246         struct list_head *list_node = NULL;
 247         bool found = false;
 248
 249         list_for_each(list_node, &edev->rdma_info.rdma_event_list) {
 250                 event_node = list_entry(list_node, struct qede_rdma_event_work,
 251                                         list);
 252                 if (!work_pending(&event_node->work)) {
 253                         found = true;
 254                         break;
 255                 }
 256         }
 257
 258         if (!found) {
 259                 event_node = kzalloc(sizeof(*event_node), GFP_ATOMIC);
 260                 if (!event_node) {
 261                         DP_NOTICE(edev,
 262                                   "qedr: Could not allocate memory for rdma work\n");
 263                         return NULL;
 264                 }
 265                 list_add_tail(&event_node->list,
 266                               &edev->rdma_info.rdma_event_list);
 267         }
 268
 269         return event_node;
 270 }
 271
 272 static void qede_rdma_handle_event(struct work_struct *work)
 273 {
 274         struct qede_rdma_event_work *event_node;
 275         enum qede_rdma_event event;
 276         struct qede_dev *edev;
 277
 278         event_node = container_of(work, struct qede_rdma_event_work, work);
 279         event = event_node->event;
 280         edev = event_node->ptr;
 281
 282         switch (event) {
 283         case QEDE_UP:
 284                 qede_rdma_dev_open(edev);
 285                 break;
 286         case QEDE_DOWN:
 287                 qede_rdma_dev_close(edev);
 288                 break;
 289         case QEDE_CLOSE:
 290                 qede_rdma_dev_shutdown(edev);
 291                 break;
 292         case QEDE_CHANGE_ADDR:
 293                 qede_rdma_changeaddr(edev);
 294                 break;
 295         default:
 296                 DP_NOTICE(edev, "Invalid rdma event %d", event);
 297         }
 298 }
 299
 300 static void qede_rdma_add_event(struct qede_dev *edev,
 301                                 enum qede_rdma_event event)
 302 {
 303         struct qede_rdma_event_work *event_node;
 304
 305         if (!edev->rdma_info.qedr_dev)
 306                 return;
 307
 308         /* We don't want the cleanup flow to start while we're allocating and
 309          * scheduling the work
 310          */
 311         if (!kref_get_unless_zero(&edev->rdma_info.refcnt))
 312                 return; /* already being destroyed */
 313
 314         event_node = qede_rdma_get_free_event_node(edev);
 315         if (!event_node)
 316                 goto out;
 317
 318         event_node->event = event;
 319         event_node->ptr = edev;
 320
 321         INIT_WORK(&event_node->work, qede_rdma_handle_event);
 322         queue_work(edev->rdma_info.rdma_wq, &event_node->work);
 323
 324 out:
 325         kref_put(&edev->rdma_info.refcnt, qede_rdma_complete_event);
 326 }
 327
 328 void qede_rdma_dev_event_open(struct qede_dev *edev)
 329 {
 330         qede_rdma_add_event(edev, QEDE_UP);
 331 }
 332
 333 void qede_rdma_dev_event_close(struct qede_dev *edev)
 334 {
 335         qede_rdma_add_event(edev, QEDE_DOWN);
 336 }
 337
 338 void qede_rdma_event_changeaddr(struct qede_dev *edev)
 339 {
 340         qede_rdma_add_event(edev, QEDE_CHANGE_ADDR);
 341 }