drivers/infiniband/core/uverbs_main.c

   1 /*
   2  * Copyright (c) 2005 Topspin Communications.  All rights reserved.
   3  * Copyright (c) 2005, 2006 Cisco Systems.  All rights reserved.
   4  * Copyright (c) 2005 Mellanox Technologies. All rights reserved.
   5  * Copyright (c) 2005 Voltaire, Inc. All rights reserved.
   6  * Copyright (c) 2005 PathScale, Inc. All rights reserved.
   7  *
   8  * This software is available to you under a choice of one of two
   9  * licenses.  You may choose to be licensed under the terms of the GNU
  10  * General Public License (GPL) Version 2, available from the file
  11  * COPYING in the main directory of this source tree, or the
  12  * OpenIB.org BSD license below:
  13  *
  14  *     Redistribution and use in source and binary forms, with or
  15  *     without modification, are permitted provided that the following
  16  *     conditions are met:
  17  *
  18  *      - Redistributions of source code must retain the above
  19  *        copyright notice, this list of conditions and the following
  20  *        disclaimer.
  21  *
  22  *      - Redistributions in binary form must reproduce the above
  23  *        copyright notice, this list of conditions and the following
  24  *        disclaimer in the documentation and/or other materials
  25  *        provided with the distribution.
  26  *
  27  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  28  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  29  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  30  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  31  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  32  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  33  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  34  * SOFTWARE.
  35  */
  36
  37 #include <linux/module.h>
  38 #include <linux/init.h>
  39 #include <linux/device.h>
  40 #include <linux/err.h>
  41 #include <linux/fs.h>
  42 #include <linux/poll.h>
  43 #include <linux/sched.h>
  44 #include <linux/file.h>
  45 #include <linux/cdev.h>
  46 #include <linux/anon_inodes.h>
  47 #include <linux/slab.h>
  48 #include <linux/sched/mm.h>
  49
  50 #include <linux/uaccess.h>
  51
  52 #include <rdma/ib.h>
  53 #include <rdma/uverbs_std_types.h>
  54 #include <rdma/rdma_netlink.h>
  55
  56 #include "uverbs.h"
  57 #include "core_priv.h"
  58 #include "rdma_core.h"
  59
  60 MODULE_AUTHOR("Roland Dreier");
  61 MODULE_DESCRIPTION("InfiniBand userspace verbs access");
  62 MODULE_LICENSE("Dual BSD/GPL");
  63
  64 enum {
  65         IB_UVERBS_MAJOR       = 231,
  66         IB_UVERBS_BASE_MINOR  = 192,
  67         IB_UVERBS_MAX_DEVICES = RDMA_MAX_PORTS,
  68         IB_UVERBS_NUM_FIXED_MINOR = 32,
  69         IB_UVERBS_NUM_DYNAMIC_MINOR = IB_UVERBS_MAX_DEVICES - IB_UVERBS_NUM_FIXED_MINOR,
  70 };
  71
  72 #define IB_UVERBS_BASE_DEV      MKDEV(IB_UVERBS_MAJOR, IB_UVERBS_BASE_MINOR)
  73
  74 static dev_t dynamic_uverbs_dev;
  75 static struct class *uverbs_class;
  76
  77 static DEFINE_IDA(uverbs_ida);
  78 static void ib_uverbs_add_one(struct ib_device *device);
  79 static void ib_uverbs_remove_one(struct ib_device *device, void *client_data);
  80
  81 /*
  82  * Must be called with the ufile->device->disassociate_srcu held, and the lock
  83  * must be held until use of the ucontext is finished.
  84  */
  85 struct ib_ucontext *ib_uverbs_get_ucontext_file(struct ib_uverbs_file *ufile)
  86 {
  87         /*
  88          * We do not hold the hw_destroy_rwsem lock for this flow, instead
  89          * srcu is used. It does not matter if someone races this with
  90          * get_context, we get NULL or valid ucontext.
  91          */
  92         struct ib_ucontext *ucontext = smp_load_acquire(&ufile->ucontext);
  93
  94         if (!srcu_dereference(ufile->device->ib_dev,
  95                               &ufile->device->disassociate_srcu))
  96                 return ERR_PTR(-EIO);
  97
  98         if (!ucontext)
  99                 return ERR_PTR(-EINVAL);
 100
 101         return ucontext;
 102 }
 103 EXPORT_SYMBOL(ib_uverbs_get_ucontext_file);
 104
 105 int uverbs_dealloc_mw(struct ib_mw *mw)
 106 {
 107         struct ib_pd *pd = mw->pd;
 108         int ret;
 109
 110         ret = mw->device->ops.dealloc_mw(mw);
 111         if (!ret)
 112                 atomic_dec(&pd->usecnt);
 113         return ret;
 114 }
 115
 116 static void ib_uverbs_release_dev(struct device *device)
 117 {
 118         struct ib_uverbs_device *dev =
 119                         container_of(device, struct ib_uverbs_device, dev);
 120
 121         uverbs_destroy_api(dev->uapi);
 122         cleanup_srcu_struct(&dev->disassociate_srcu);
 123         mutex_destroy(&dev->lists_mutex);
 124         mutex_destroy(&dev->xrcd_tree_mutex);
 125         kfree(dev);
 126 }
 127
 128 static void ib_uverbs_release_async_event_file(struct kref *ref)
 129 {
 130         struct ib_uverbs_async_event_file *file =
 131                 container_of(ref, struct ib_uverbs_async_event_file, ref);
 132
 133         kfree(file);
 134 }
 135
 136 void ib_uverbs_release_ucq(struct ib_uverbs_file *file,
 137                           struct ib_uverbs_completion_event_file *ev_file,
 138                           struct ib_ucq_object *uobj)
 139 {
 140         struct ib_uverbs_event *evt, *tmp;
 141
 142         if (ev_file) {
 143                 spin_lock_irq(&ev_file->ev_queue.lock);
 144                 list_for_each_entry_safe(evt, tmp, &uobj->comp_list, obj_list) {
 145                         list_del(&evt->list);
 146                         kfree(evt);
 147                 }
 148                 spin_unlock_irq(&ev_file->ev_queue.lock);
 149
 150                 uverbs_uobject_put(&ev_file->uobj);
 151         }
 152
 153         spin_lock_irq(&file->async_file->ev_queue.lock);
 154         list_for_each_entry_safe(evt, tmp, &uobj->async_list, obj_list) {
 155                 list_del(&evt->list);
 156                 kfree(evt);
 157         }
 158         spin_unlock_irq(&file->async_file->ev_queue.lock);
 159 }
 160
 161 void ib_uverbs_release_uevent(struct ib_uverbs_file *file,
 162                               struct ib_uevent_object *uobj)
 163 {
 164         struct ib_uverbs_event *evt, *tmp;
 165
 166         spin_lock_irq(&file->async_file->ev_queue.lock);
 167         list_for_each_entry_safe(evt, tmp, &uobj->event_list, obj_list) {
 168                 list_del(&evt->list);
 169                 kfree(evt);
 170         }
 171         spin_unlock_irq(&file->async_file->ev_queue.lock);
 172 }
 173
 174 void ib_uverbs_detach_umcast(struct ib_qp *qp,
 175                              struct ib_uqp_object *uobj)
 176 {
 177         struct ib_uverbs_mcast_entry *mcast, *tmp;
 178
 179         list_for_each_entry_safe(mcast, tmp, &uobj->mcast_list, list) {
 180                 ib_detach_mcast(qp, &mcast->gid, mcast->lid);
 181                 list_del(&mcast->list);
 182                 kfree(mcast);
 183         }
 184 }
 185
 186 static void ib_uverbs_comp_dev(struct ib_uverbs_device *dev)
 187 {
 188         complete(&dev->comp);
 189 }
 190
 191 void ib_uverbs_release_file(struct kref *ref)
 192 {
 193         struct ib_uverbs_file *file =
 194                 container_of(ref, struct ib_uverbs_file, ref);
 195         struct ib_device *ib_dev;
 196         int srcu_key;
 197
 198         release_ufile_idr_uobject(file);
 199
 200         srcu_key = srcu_read_lock(&file->device->disassociate_srcu);
 201         ib_dev = srcu_dereference(file->device->ib_dev,
 202                                   &file->device->disassociate_srcu);
 203         if (ib_dev && !ib_dev->ops.disassociate_ucontext)
 204                 module_put(ib_dev->ops.owner);
 205         srcu_read_unlock(&file->device->disassociate_srcu, srcu_key);
 206
 207         if (atomic_dec_and_test(&file->device->refcount))
 208                 ib_uverbs_comp_dev(file->device);
 209
 210         if (file->async_file)
 211                 kref_put(&file->async_file->ref,
 212                          ib_uverbs_release_async_event_file);
 213         put_device(&file->device->dev);
 214
 215         if (file->disassociate_page)
 216                 __free_pages(file->disassociate_page, 0);
 217         mutex_destroy(&file->umap_lock);
 218         mutex_destroy(&file->ucontext_lock);
 219         kfree(file);
 220 }
 221
 222 static ssize_t ib_uverbs_event_read(struct ib_uverbs_event_queue *ev_queue,
 223                                     struct file *filp, char __user *buf,
 224                                     size_t count, loff_t *pos,
 225                                     size_t eventsz)
 226 {
 227         struct ib_uverbs_event *event;
 228         int ret = 0;
 229
 230         spin_lock_irq(&ev_queue->lock);
 231
 232         while (list_empty(&ev_queue->event_list)) {
 233                 spin_unlock_irq(&ev_queue->lock);
 234
 235                 if (filp->f_flags & O_NONBLOCK)
 236                         return -EAGAIN;
 237
 238                 if (wait_event_interruptible(ev_queue->poll_wait,
 239                                              (!list_empty(&ev_queue->event_list) ||
 240                                               ev_queue->is_closed)))
 241                         return -ERESTARTSYS;
 242
 243                 spin_lock_irq(&ev_queue->lock);
 244
 245                 /* If device was disassociated and no event exists set an error */
 246                 if (list_empty(&ev_queue->event_list) && ev_queue->is_closed) {
 247                         spin_unlock_irq(&ev_queue->lock);
 248                         return -EIO;
 249                 }
 250         }
 251
 252         event = list_entry(ev_queue->event_list.next, struct ib_uverbs_event, list);
 253
 254         if (eventsz > count) {
 255                 ret   = -EINVAL;
 256                 event = NULL;
 257         } else {
 258                 list_del(ev_queue->event_list.next);
 259                 if (event->counter) {
 260                         ++(*event->counter);
 261                         list_del(&event->obj_list);
 262                 }
 263         }
 264
 265         spin_unlock_irq(&ev_queue->lock);
 266
 267         if (event) {
 268                 if (copy_to_user(buf, event, eventsz))
 269                         ret = -EFAULT;
 270                 else
 271                         ret = eventsz;
 272         }
 273
 274         kfree(event);
 275
 276         return ret;
 277 }
 278
 279 static ssize_t ib_uverbs_async_event_read(struct file *filp, char __user *buf,
 280                                           size_t count, loff_t *pos)
 281 {
 282         struct ib_uverbs_async_event_file *file = filp->private_data;
 283
 284         return ib_uverbs_event_read(&file->ev_queue, filp, buf, count, pos,
 285                                     sizeof(struct ib_uverbs_async_event_desc));
 286 }
 287
 288 static ssize_t ib_uverbs_comp_event_read(struct file *filp, char __user *buf,
 289                                          size_t count, loff_t *pos)
 290 {
 291         struct ib_uverbs_completion_event_file *comp_ev_file =
 292                 filp->private_data;
 293
 294         return ib_uverbs_event_read(&comp_ev_file->ev_queue, filp, buf, count,
 295                                     pos,
 296                                     sizeof(struct ib_uverbs_comp_event_desc));
 297 }
 298
 299 static __poll_t ib_uverbs_event_poll(struct ib_uverbs_event_queue *ev_queue,
 300                                          struct file *filp,
 301                                          struct poll_table_struct *wait)
 302 {
 303         __poll_t pollflags = 0;
 304
 305         poll_wait(filp, &ev_queue->poll_wait, wait);
 306
 307         spin_lock_irq(&ev_queue->lock);
 308         if (!list_empty(&ev_queue->event_list))
 309                 pollflags = EPOLLIN | EPOLLRDNORM;
 310         spin_unlock_irq(&ev_queue->lock);
 311
 312         return pollflags;
 313 }
 314
 315 static __poll_t ib_uverbs_async_event_poll(struct file *filp,
 316                                                struct poll_table_struct *wait)
 317 {
 318         struct ib_uverbs_async_event_file *file = filp->private_data;
 319
 320         return ib_uverbs_event_poll(&file->ev_queue, filp, wait);
 321 }
 322
 323 static __poll_t ib_uverbs_comp_event_poll(struct file *filp,
 324                                               struct poll_table_struct *wait)
 325 {
 326         struct ib_uverbs_completion_event_file *comp_ev_file =
 327                 filp->private_data;
 328
 329         return ib_uverbs_event_poll(&comp_ev_file->ev_queue, filp, wait);
 330 }
 331
 332 static int ib_uverbs_async_event_fasync(int fd, struct file *filp, int on)
 333 {
 334         struct ib_uverbs_async_event_file *file = filp->private_data;
 335
 336         return fasync_helper(fd, filp, on, &file->ev_queue.async_queue);
 337 }
 338
 339 static int ib_uverbs_comp_event_fasync(int fd, struct file *filp, int on)
 340 {
 341         struct ib_uverbs_completion_event_file *comp_ev_file =
 342                 filp->private_data;
 343
 344         return fasync_helper(fd, filp, on, &comp_ev_file->ev_queue.async_queue);
 345 }
 346
 347 static int ib_uverbs_async_event_close(struct inode *inode, struct file *filp)
 348 {
 349         struct ib_uverbs_async_event_file *file = filp->private_data;
 350         struct ib_uverbs_file *uverbs_file = file->uverbs_file;
 351         struct ib_uverbs_event *entry, *tmp;
 352         int closed_already = 0;
 353
 354         mutex_lock(&uverbs_file->device->lists_mutex);
 355         spin_lock_irq(&file->ev_queue.lock);
 356         closed_already = file->ev_queue.is_closed;
 357         file->ev_queue.is_closed = 1;
 358         list_for_each_entry_safe(entry, tmp, &file->ev_queue.event_list, list) {
 359                 if (entry->counter)
 360                         list_del(&entry->obj_list);
 361                 kfree(entry);
 362         }
 363         spin_unlock_irq(&file->ev_queue.lock);
 364         if (!closed_already) {
 365                 list_del(&file->list);
 366                 ib_unregister_event_handler(&uverbs_file->event_handler);
 367         }
 368         mutex_unlock(&uverbs_file->device->lists_mutex);
 369
 370         kref_put(&uverbs_file->ref, ib_uverbs_release_file);
 371         kref_put(&file->ref, ib_uverbs_release_async_event_file);
 372
 373         return 0;
 374 }
 375
 376 const struct file_operations uverbs_event_fops = {
 377         .owner   = THIS_MODULE,
 378         .read    = ib_uverbs_comp_event_read,
 379         .poll    = ib_uverbs_comp_event_poll,
 380         .release = uverbs_uobject_fd_release,
 381         .fasync  = ib_uverbs_comp_event_fasync,
 382         .llseek  = no_llseek,
 383 };
 384
 385 static const struct file_operations uverbs_async_event_fops = {
 386         .owner   = THIS_MODULE,
 387         .read    = ib_uverbs_async_event_read,
 388         .poll    = ib_uverbs_async_event_poll,
 389         .release = ib_uverbs_async_event_close,
 390         .fasync  = ib_uverbs_async_event_fasync,
 391         .llseek  = no_llseek,
 392 };
 393
 394 void ib_uverbs_comp_handler(struct ib_cq *cq, void *cq_context)
 395 {
 396         struct ib_uverbs_event_queue   *ev_queue = cq_context;
 397         struct ib_ucq_object           *uobj;
 398         struct ib_uverbs_event         *entry;
 399         unsigned long                   flags;
 400
 401         if (!ev_queue)
 402                 return;
 403
 404         spin_lock_irqsave(&ev_queue->lock, flags);
 405         if (ev_queue->is_closed) {
 406                 spin_unlock_irqrestore(&ev_queue->lock, flags);
 407                 return;
 408         }
 409
 410         entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
 411         if (!entry) {
 412                 spin_unlock_irqrestore(&ev_queue->lock, flags);
 413                 return;
 414         }
 415
 416         uobj = container_of(cq->uobject, struct ib_ucq_object, uobject);
 417
 418         entry->desc.comp.cq_handle = cq->uobject->user_handle;
 419         entry->counter             = &uobj->comp_events_reported;
 420
 421         list_add_tail(&entry->list, &ev_queue->event_list);
 422         list_add_tail(&entry->obj_list, &uobj->comp_list);
 423         spin_unlock_irqrestore(&ev_queue->lock, flags);
 424
 425         wake_up_interruptible(&ev_queue->poll_wait);
 426         kill_fasync(&ev_queue->async_queue, SIGIO, POLL_IN);
 427 }
 428
 429 static void ib_uverbs_async_handler(struct ib_uverbs_file *file,
 430                                     __u64 element, __u64 event,
 431                                     struct list_head *obj_list,
 432                                     u32 *counter)
 433 {
 434         struct ib_uverbs_event *entry;
 435         unsigned long flags;
 436
 437         spin_lock_irqsave(&file->async_file->ev_queue.lock, flags);
 438         if (file->async_file->ev_queue.is_closed) {
 439                 spin_unlock_irqrestore(&file->async_file->ev_queue.lock, flags);
 440                 return;
 441         }
 442
 443         entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
 444         if (!entry) {
 445                 spin_unlock_irqrestore(&file->async_file->ev_queue.lock, flags);
 446                 return;
 447         }
 448
 449         entry->desc.async.element    = element;
 450         entry->desc.async.event_type = event;
 451         entry->desc.async.reserved   = 0;
 452         entry->counter               = counter;
 453
 454         list_add_tail(&entry->list, &file->async_file->ev_queue.event_list);
 455         if (obj_list)
 456                 list_add_tail(&entry->obj_list, obj_list);
 457         spin_unlock_irqrestore(&file->async_file->ev_queue.lock, flags);
 458
 459         wake_up_interruptible(&file->async_file->ev_queue.poll_wait);
 460         kill_fasync(&file->async_file->ev_queue.async_queue, SIGIO, POLL_IN);
 461 }
 462
 463 void ib_uverbs_cq_event_handler(struct ib_event *event, void *context_ptr)
 464 {
 465         struct ib_ucq_object *uobj = container_of(event->element.cq->uobject,
 466                                                   struct ib_ucq_object, uobject);
 467
 468         ib_uverbs_async_handler(uobj->uobject.ufile, uobj->uobject.user_handle,
 469                                 event->event, &uobj->async_list,
 470                                 &uobj->async_events_reported);
 471 }
 472
 473 void ib_uverbs_qp_event_handler(struct ib_event *event, void *context_ptr)
 474 {
 475         struct ib_uevent_object *uobj;
 476
 477         /* for XRC target qp's, check that qp is live */
 478         if (!event->element.qp->uobject)
 479                 return;
 480
 481         uobj = container_of(event->element.qp->uobject,
 482                             struct ib_uevent_object, uobject);
 483
 484         ib_uverbs_async_handler(context_ptr, uobj->uobject.user_handle,
 485                                 event->event, &uobj->event_list,
 486                                 &uobj->events_reported);
 487 }
 488
 489 void ib_uverbs_wq_event_handler(struct ib_event *event, void *context_ptr)
 490 {
 491         struct ib_uevent_object *uobj = container_of(event->element.wq->uobject,
 492                                                   struct ib_uevent_object, uobject);
 493
 494         ib_uverbs_async_handler(context_ptr, uobj->uobject.user_handle,
 495                                 event->event, &uobj->event_list,
 496                                 &uobj->events_reported);
 497 }
 498
 499 void ib_uverbs_srq_event_handler(struct ib_event *event, void *context_ptr)
 500 {
 501         struct ib_uevent_object *uobj;
 502
 503         uobj = container_of(event->element.srq->uobject,
 504                             struct ib_uevent_object, uobject);
 505
 506         ib_uverbs_async_handler(context_ptr, uobj->uobject.user_handle,
 507                                 event->event, &uobj->event_list,
 508                                 &uobj->events_reported);
 509 }
 510
 511 void ib_uverbs_event_handler(struct ib_event_handler *handler,
 512                              struct ib_event *event)
 513 {
 514         struct ib_uverbs_file *file =
 515                 container_of(handler, struct ib_uverbs_file, event_handler);
 516
 517         ib_uverbs_async_handler(file, event->element.port_num, event->event,
 518                                 NULL, NULL);
 519 }
 520
 521 void ib_uverbs_free_async_event_file(struct ib_uverbs_file *file)
 522 {
 523         kref_put(&file->async_file->ref, ib_uverbs_release_async_event_file);
 524         file->async_file = NULL;
 525 }
 526
 527 void ib_uverbs_init_event_queue(struct ib_uverbs_event_queue *ev_queue)
 528 {
 529         spin_lock_init(&ev_queue->lock);
 530         INIT_LIST_HEAD(&ev_queue->event_list);
 531         init_waitqueue_head(&ev_queue->poll_wait);
 532         ev_queue->is_closed   = 0;
 533         ev_queue->async_queue = NULL;
 534 }
 535
 536 struct file *ib_uverbs_alloc_async_event_file(struct ib_uverbs_file *uverbs_file,
 537                                               struct ib_device  *ib_dev)
 538 {
 539         struct ib_uverbs_async_event_file *ev_file;
 540         struct file *filp;
 541
 542         ev_file = kzalloc(sizeof(*ev_file), GFP_KERNEL);
 543         if (!ev_file)
 544                 return ERR_PTR(-ENOMEM);
 545
 546         ib_uverbs_init_event_queue(&ev_file->ev_queue);
 547         ev_file->uverbs_file = uverbs_file;
 548         kref_get(&ev_file->uverbs_file->ref);
 549         kref_init(&ev_file->ref);
 550         filp = anon_inode_getfile("[infinibandevent]", &uverbs_async_event_fops,
 551                                   ev_file, O_RDONLY);
 552         if (IS_ERR(filp))
 553                 goto err_put_refs;
 554
 555         mutex_lock(&uverbs_file->device->lists_mutex);
 556         list_add_tail(&ev_file->list,
 557                       &uverbs_file->device->uverbs_events_file_list);
 558         mutex_unlock(&uverbs_file->device->lists_mutex);
 559
 560         WARN_ON(uverbs_file->async_file);
 561         uverbs_file->async_file = ev_file;
 562         kref_get(&uverbs_file->async_file->ref);
 563         INIT_IB_EVENT_HANDLER(&uverbs_file->event_handler,
 564                               ib_dev,
 565                               ib_uverbs_event_handler);
 566         ib_register_event_handler(&uverbs_file->event_handler);
 567         /* At that point async file stuff was fully set */
 568
 569         return filp;
 570
 571 err_put_refs:
 572         kref_put(&ev_file->uverbs_file->ref, ib_uverbs_release_file);
 573         kref_put(&ev_file->ref, ib_uverbs_release_async_event_file);
 574         return filp;
 575 }
 576
 577 static ssize_t verify_hdr(struct ib_uverbs_cmd_hdr *hdr,
 578                           struct ib_uverbs_ex_cmd_hdr *ex_hdr, size_t count,
 579                           const struct uverbs_api_write_method *method_elm)
 580 {
 581         if (method_elm->is_ex) {
 582                 count -= sizeof(*hdr) + sizeof(*ex_hdr);
 583
 584                 if ((hdr->in_words + ex_hdr->provider_in_words) * 8 != count)
 585                         return -EINVAL;
 586
 587                 if (hdr->in_words * 8 < method_elm->req_size)
 588                         return -ENOSPC;
 589
 590                 if (ex_hdr->cmd_hdr_reserved)
 591                         return -EINVAL;
 592
 593                 if (ex_hdr->response) {
 594                         if (!hdr->out_words && !ex_hdr->provider_out_words)
 595                                 return -EINVAL;
 596
 597                         if (hdr->out_words * 8 < method_elm->resp_size)
 598                                 return -ENOSPC;
 599
 600                         if (!access_ok(u64_to_user_ptr(ex_hdr->response),
 601                                        (hdr->out_words + ex_hdr->provider_out_words) * 8))
 602                                 return -EFAULT;
 603                 } else {
 604                         if (hdr->out_words || ex_hdr->provider_out_words)
 605                                 return -EINVAL;
 606                 }
 607
 608                 return 0;
 609         }
 610
 611         /* not extended command */
 612         if (hdr->in_words * 4 != count)
 613                 return -EINVAL;
 614
 615         if (count < method_elm->req_size + sizeof(hdr)) {
 616                 /*
 617                  * rdma-core v18 and v19 have a bug where they send DESTROY_CQ
 618                  * with a 16 byte write instead of 24. Old kernels didn't
 619                  * check the size so they allowed this. Now that the size is
 620                  * checked provide a compatibility work around to not break
 621                  * those userspaces.
 622                  */
 623                 if (hdr->command == IB_USER_VERBS_CMD_DESTROY_CQ &&
 624                     count == 16) {
 625                         hdr->in_words = 6;
 626                         return 0;
 627                 }
 628                 return -ENOSPC;
 629         }
 630         if (hdr->out_words * 4 < method_elm->resp_size)
 631                 return -ENOSPC;
 632
 633         return 0;
 634 }
 635
 636 static ssize_t ib_uverbs_write(struct file *filp, const char __user *buf,
 637                              size_t count, loff_t *pos)
 638 {
 639         struct ib_uverbs_file *file = filp->private_data;
 640         const struct uverbs_api_write_method *method_elm;
 641         struct uverbs_api *uapi = file->device->uapi;
 642         struct ib_uverbs_ex_cmd_hdr ex_hdr;
 643         struct ib_uverbs_cmd_hdr hdr;
 644         struct uverbs_attr_bundle bundle;
 645         int srcu_key;
 646         ssize_t ret;
 647
 648         if (!ib_safe_file_access(filp)) {
 649                 pr_err_once("uverbs_write: process %d (%s) changed security contexts after opening file descriptor, this is not allowed.\n",
 650                             task_tgid_vnr(current), current->comm);
 651                 return -EACCES;
 652         }
 653
 654         if (count < sizeof(hdr))
 655                 return -EINVAL;
 656
 657         if (copy_from_user(&hdr, buf, sizeof(hdr)))
 658                 return -EFAULT;
 659
 660         method_elm = uapi_get_method(uapi, hdr.command);
 661         if (IS_ERR(method_elm))
 662                 return PTR_ERR(method_elm);
 663
 664         if (method_elm->is_ex) {
 665                 if (count < (sizeof(hdr) + sizeof(ex_hdr)))
 666                         return -EINVAL;
 667                 if (copy_from_user(&ex_hdr, buf + sizeof(hdr), sizeof(ex_hdr)))
 668                         return -EFAULT;
 669         }
 670
 671         ret = verify_hdr(&hdr, &ex_hdr, count, method_elm);
 672         if (ret)
 673                 return ret;
 674
 675         srcu_key = srcu_read_lock(&file->device->disassociate_srcu);
 676
 677         buf += sizeof(hdr);
 678
 679         memset(bundle.attr_present, 0, sizeof(bundle.attr_present));
 680         bundle.ufile = file;
 681         bundle.context = NULL; /* only valid if bundle has uobject */
 682         if (!method_elm->is_ex) {
 683                 size_t in_len = hdr.in_words * 4 - sizeof(hdr);
 684                 size_t out_len = hdr.out_words * 4;
 685                 u64 response = 0;
 686
 687                 if (method_elm->has_udata) {
 688                         bundle.driver_udata.inlen =
 689                                 in_len - method_elm->req_size;
 690                         in_len = method_elm->req_size;
 691                         if (bundle.driver_udata.inlen)
 692                                 bundle.driver_udata.inbuf = buf + in_len;
 693                         else
 694                                 bundle.driver_udata.inbuf = NULL;
 695                 } else {
 696                         memset(&bundle.driver_udata, 0,
 697                                sizeof(bundle.driver_udata));
 698                 }
 699
 700                 if (method_elm->has_resp) {
 701                         /*
 702                          * The macros check that if has_resp is set
 703                          * then the command request structure starts
 704                          * with a '__aligned u64 response' member.
 705                          */
 706                         ret = get_user(response, (const u64 __user *)buf);
 707                         if (ret)
 708                                 goto out_unlock;
 709
 710                         if (method_elm->has_udata) {
 711                                 bundle.driver_udata.outlen =
 712                                         out_len - method_elm->resp_size;
 713                                 out_len = method_elm->resp_size;
 714                                 if (bundle.driver_udata.outlen)
 715                                         bundle.driver_udata.outbuf =
 716                                                 u64_to_user_ptr(response +
 717                                                                 out_len);
 718                                 else
 719                                         bundle.driver_udata.outbuf = NULL;
 720                         }
 721                 } else {
 722                         bundle.driver_udata.outlen = 0;
 723                         bundle.driver_udata.outbuf = NULL;
 724                 }
 725
 726                 ib_uverbs_init_udata_buf_or_null(
 727                         &bundle.ucore, buf, u64_to_user_ptr(response),
 728                         in_len, out_len);
 729         } else {
 730                 buf += sizeof(ex_hdr);
 731
 732                 ib_uverbs_init_udata_buf_or_null(&bundle.ucore, buf,
 733                                         u64_to_user_ptr(ex_hdr.response),
 734                                         hdr.in_words * 8, hdr.out_words * 8);
 735
 736                 ib_uverbs_init_udata_buf_or_null(
 737                         &bundle.driver_udata, buf + bundle.ucore.inlen,
 738                         u64_to_user_ptr(ex_hdr.response) + bundle.ucore.outlen,
 739                         ex_hdr.provider_in_words * 8,
 740                         ex_hdr.provider_out_words * 8);
 741
 742         }
 743
 744         ret = method_elm->handler(&bundle);
 745 out_unlock:
 746         srcu_read_unlock(&file->device->disassociate_srcu, srcu_key);
 747         return (ret) ? : count;
 748 }
 749
 750 static const struct vm_operations_struct rdma_umap_ops;
 751
 752 static int ib_uverbs_mmap(struct file *filp, struct vm_area_struct *vma)
 753 {
 754         struct ib_uverbs_file *file = filp->private_data;
 755         struct ib_ucontext *ucontext;
 756         int ret = 0;
 757         int srcu_key;
 758
 759         srcu_key = srcu_read_lock(&file->device->disassociate_srcu);
 760         ucontext = ib_uverbs_get_ucontext_file(file);
 761         if (IS_ERR(ucontext)) {
 762                 ret = PTR_ERR(ucontext);
 763                 goto out;
 764         }
 765         vma->vm_ops = &rdma_umap_ops;
 766         ret = ucontext->device->ops.mmap(ucontext, vma);
 767 out:
 768         srcu_read_unlock(&file->device->disassociate_srcu, srcu_key);
 769         return ret;
 770 }
 771
 772 /*
 773  * The VMA has been dup'd, initialize the vm_private_data with a new tracking
 774  * struct
 775  */
 776 static void rdma_umap_open(struct vm_area_struct *vma)
 777 {
 778         struct ib_uverbs_file *ufile = vma->vm_file->private_data;
 779         struct rdma_umap_priv *opriv = vma->vm_private_data;
 780         struct rdma_umap_priv *priv;
 781
 782         if (!opriv)
 783                 return;
 784
 785         /* We are racing with disassociation */
 786         if (!down_read_trylock(&ufile->hw_destroy_rwsem))
 787                 goto out_zap;
 788         /*
 789          * Disassociation already completed, the VMA should already be zapped.
 790          */
 791         if (!ufile->ucontext)
 792                 goto out_unlock;
 793
 794         priv = kzalloc(sizeof(*priv), GFP_KERNEL);
 795         if (!priv)
 796                 goto out_unlock;
 797         rdma_umap_priv_init(priv, vma, opriv->entry);
 798
 799         up_read(&ufile->hw_destroy_rwsem);
 800         return;
 801
 802 out_unlock:
 803         up_read(&ufile->hw_destroy_rwsem);
 804 out_zap:
 805         /*
 806          * We can't allow the VMA to be created with the actual IO pages, that
 807          * would break our API contract, and it can't be stopped at this
 808          * point, so zap it.
 809          */
 810         vma->vm_private_data = NULL;
 811         zap_vma_ptes(vma, vma->vm_start, vma->vm_end - vma->vm_start);
 812 }
 813
 814 static void rdma_umap_close(struct vm_area_struct *vma)
 815 {
 816         struct ib_uverbs_file *ufile = vma->vm_file->private_data;
 817         struct rdma_umap_priv *priv = vma->vm_private_data;
 818
 819         if (!priv)
 820                 return;
 821
 822         /*
 823          * The vma holds a reference on the struct file that created it, which
 824          * in turn means that the ib_uverbs_file is guaranteed to exist at
 825          * this point.
 826          */
 827         mutex_lock(&ufile->umap_lock);
 828         if (priv->entry)
 829                 rdma_user_mmap_entry_put(priv->entry);
 830
 831         list_del(&priv->list);
 832         mutex_unlock(&ufile->umap_lock);
 833         kfree(priv);
 834 }
 835
 836 /*
 837  * Once the zap_vma_ptes has been called touches to the VMA will come here and
 838  * we return a dummy writable zero page for all the pfns.
 839  */
 840 static vm_fault_t rdma_umap_fault(struct vm_fault *vmf)
 841 {
 842         struct ib_uverbs_file *ufile = vmf->vma->vm_file->private_data;
 843         struct rdma_umap_priv *priv = vmf->vma->vm_private_data;
 844         vm_fault_t ret = 0;
 845
 846         if (!priv)
 847                 return VM_FAULT_SIGBUS;
 848
 849         /* Read only pages can just use the system zero page. */
 850         if (!(vmf->vma->vm_flags & (VM_WRITE | VM_MAYWRITE))) {
 851                 vmf->page = ZERO_PAGE(vmf->address);
 852                 get_page(vmf->page);
 853                 return 0;
 854         }
 855
 856         mutex_lock(&ufile->umap_lock);
 857         if (!ufile->disassociate_page)
 858                 ufile->disassociate_page =
 859                         alloc_pages(vmf->gfp_mask | __GFP_ZERO, 0);
 860
 861         if (ufile->disassociate_page) {
 862                 /*
 863                  * This VMA is forced to always be shared so this doesn't have
 864                  * to worry about COW.
 865                  */
 866                 vmf->page = ufile->disassociate_page;
 867                 get_page(vmf->page);
 868         } else {
 869                 ret = VM_FAULT_SIGBUS;
 870         }
 871         mutex_unlock(&ufile->umap_lock);
 872
 873         return ret;
 874 }
 875
 876 static const struct vm_operations_struct rdma_umap_ops = {
 877         .open = rdma_umap_open,
 878         .close = rdma_umap_close,
 879         .fault = rdma_umap_fault,
 880 };
 881
 882 void uverbs_user_mmap_disassociate(struct ib_uverbs_file *ufile)
 883 {
 884         struct rdma_umap_priv *priv, *next_priv;
 885
 886         lockdep_assert_held(&ufile->hw_destroy_rwsem);
 887
 888         while (1) {
 889                 struct mm_struct *mm = NULL;
 890
 891                 /* Get an arbitrary mm pointer that hasn't been cleaned yet */
 892                 mutex_lock(&ufile->umap_lock);
 893                 while (!list_empty(&ufile->umaps)) {
 894                         int ret;
 895
 896                         priv = list_first_entry(&ufile->umaps,
 897                                                 struct rdma_umap_priv, list);
 898                         mm = priv->vma->vm_mm;
 899                         ret = mmget_not_zero(mm);
 900                         if (!ret) {
 901                                 list_del_init(&priv->list);
 902                                 mm = NULL;
 903                                 continue;
 904                         }
 905                         break;
 906                 }
 907                 mutex_unlock(&ufile->umap_lock);
 908                 if (!mm)
 909                         return;
 910
 911                 /*
 912                  * The umap_lock is nested under mmap_sem since it used within
 913                  * the vma_ops callbacks, so we have to clean the list one mm
 914                  * at a time to get the lock ordering right. Typically there
 915                  * will only be one mm, so no big deal.
 916                  */
 917                 down_read(&mm->mmap_sem);
 918                 if (!mmget_still_valid(mm))
 919                         goto skip_mm;
 920                 mutex_lock(&ufile->umap_lock);
 921                 list_for_each_entry_safe (priv, next_priv, &ufile->umaps,
 922                                           list) {
 923                         struct vm_area_struct *vma = priv->vma;
 924
 925                         if (vma->vm_mm != mm)
 926                                 continue;
 927                         list_del_init(&priv->list);
 928
 929                         zap_vma_ptes(vma, vma->vm_start,
 930                                      vma->vm_end - vma->vm_start);
 931
 932                         if (priv->entry) {
 933                                 rdma_user_mmap_entry_put(priv->entry);
 934                                 priv->entry = NULL;
 935                         }
 936                 }
 937                 mutex_unlock(&ufile->umap_lock);
 938         skip_mm:
 939                 up_read(&mm->mmap_sem);
 940                 mmput(mm);
 941         }
 942 }
 943
 944 /*
 945  * ib_uverbs_open() does not need the BKL:
 946  *
 947  *  - the ib_uverbs_device structures are properly reference counted and
 948  *    everything else is purely local to the file being created, so
 949  *    races against other open calls are not a problem;
 950  *  - there is no ioctl method to race against;
 951  *  - the open method will either immediately run -ENXIO, or all
 952  *    required initialization will be done.
 953  */
 954 static int ib_uverbs_open(struct inode *inode, struct file *filp)
 955 {
 956         struct ib_uverbs_device *dev;
 957         struct ib_uverbs_file *file;
 958         struct ib_device *ib_dev;
 959         int ret;
 960         int module_dependent;
 961         int srcu_key;
 962
 963         dev = container_of(inode->i_cdev, struct ib_uverbs_device, cdev);
 964         if (!atomic_inc_not_zero(&dev->refcount))
 965                 return -ENXIO;
 966
 967         get_device(&dev->dev);
 968         srcu_key = srcu_read_lock(&dev->disassociate_srcu);
 969         mutex_lock(&dev->lists_mutex);
 970         ib_dev = srcu_dereference(dev->ib_dev,
 971                                   &dev->disassociate_srcu);
 972         if (!ib_dev) {
 973                 ret = -EIO;
 974                 goto err;
 975         }
 976
 977         if (!rdma_dev_access_netns(ib_dev, current->nsproxy->net_ns)) {
 978                 ret = -EPERM;
 979                 goto err;
 980         }
 981
 982         /* In case IB device supports disassociate ucontext, there is no hard
 983          * dependency between uverbs device and its low level device.
 984          */
 985         module_dependent = !(ib_dev->ops.disassociate_ucontext);
 986
 987         if (module_dependent) {
 988                 if (!try_module_get(ib_dev->ops.owner)) {
 989                         ret = -ENODEV;
 990                         goto err;
 991                 }
 992         }
 993
 994         file = kzalloc(sizeof(*file), GFP_KERNEL);
 995         if (!file) {
 996                 ret = -ENOMEM;
 997                 if (module_dependent)
 998                         goto err_module;
 999
1000                 goto err;
1001         }
1002
1003         file->device     = dev;
1004         kref_init(&file->ref);
1005         mutex_init(&file->ucontext_lock);
1006
1007         spin_lock_init(&file->uobjects_lock);
1008         INIT_LIST_HEAD(&file->uobjects);
1009         init_rwsem(&file->hw_destroy_rwsem);
1010         mutex_init(&file->umap_lock);
1011         INIT_LIST_HEAD(&file->umaps);
1012
1013         filp->private_data = file;
1014         list_add_tail(&file->list, &dev->uverbs_file_list);
1015         mutex_unlock(&dev->lists_mutex);
1016         srcu_read_unlock(&dev->disassociate_srcu, srcu_key);
1017
1018         setup_ufile_idr_uobject(file);
1019
1020         return stream_open(inode, filp);
1021
1022 err_module:
1023         module_put(ib_dev->ops.owner);
1024
1025 err:
1026         mutex_unlock(&dev->lists_mutex);
1027         srcu_read_unlock(&dev->disassociate_srcu, srcu_key);
1028         if (atomic_dec_and_test(&dev->refcount))
1029                 ib_uverbs_comp_dev(dev);
1030
1031         put_device(&dev->dev);
1032         return ret;
1033 }
1034
1035 static int ib_uverbs_close(struct inode *inode, struct file *filp)
1036 {
1037         struct ib_uverbs_file *file = filp->private_data;
1038
1039         uverbs_destroy_ufile_hw(file, RDMA_REMOVE_CLOSE);
1040
1041         mutex_lock(&file->device->lists_mutex);
1042         list_del_init(&file->list);
1043         mutex_unlock(&file->device->lists_mutex);
1044
1045         kref_put(&file->ref, ib_uverbs_release_file);
1046
1047         return 0;
1048 }
1049
1050 static const struct file_operations uverbs_fops = {
1051         .owner   = THIS_MODULE,
1052         .write   = ib_uverbs_write,
1053         .open    = ib_uverbs_open,
1054         .release = ib_uverbs_close,
1055         .llseek  = no_llseek,
1056         .unlocked_ioctl = ib_uverbs_ioctl,
1057         .compat_ioctl = compat_ptr_ioctl,
1058 };
1059
1060 static const struct file_operations uverbs_mmap_fops = {
1061         .owner   = THIS_MODULE,
1062         .write   = ib_uverbs_write,
1063         .mmap    = ib_uverbs_mmap,
1064         .open    = ib_uverbs_open,
1065         .release = ib_uverbs_close,
1066         .llseek  = no_llseek,
1067         .unlocked_ioctl = ib_uverbs_ioctl,
1068         .compat_ioctl = compat_ptr_ioctl,
1069 };
1070
1071 static int ib_uverbs_get_nl_info(struct ib_device *ibdev, void *client_data,
1072                                  struct ib_client_nl_info *res)
1073 {
1074         struct ib_uverbs_device *uverbs_dev = client_data;
1075         int ret;
1076
1077         if (res->port != -1)
1078                 return -EINVAL;
1079
1080         res->abi = ibdev->ops.uverbs_abi_ver;
1081         res->cdev = &uverbs_dev->dev;
1082
1083         /*
1084          * To support DRIVER_ID binding in userspace some of the driver need
1085          * upgrading to expose their PCI dependent revision information
1086          * through get_context instead of relying on modalias matching. When
1087          * the drivers are fixed they can drop this flag.
1088          */
1089         if (!ibdev->ops.uverbs_no_driver_id_binding) {
1090                 ret = nla_put_u32(res->nl_msg, RDMA_NLDEV_ATTR_UVERBS_DRIVER_ID,
1091                                   ibdev->ops.driver_id);
1092                 if (ret)
1093                         return ret;
1094         }
1095         return 0;
1096 }
1097
1098 static struct ib_client uverbs_client = {
1099         .name   = "uverbs",
1100         .no_kverbs_req = true,
1101         .add    = ib_uverbs_add_one,
1102         .remove = ib_uverbs_remove_one,
1103         .get_nl_info = ib_uverbs_get_nl_info,
1104 };
1105 MODULE_ALIAS_RDMA_CLIENT("uverbs");
1106
1107 static ssize_t ibdev_show(struct device *device, struct device_attribute *attr,
1108                           char *buf)
1109 {
1110         struct ib_uverbs_device *dev =
1111                         container_of(device, struct ib_uverbs_device, dev);
1112         int ret = -ENODEV;
1113         int srcu_key;
1114         struct ib_device *ib_dev;
1115
1116         srcu_key = srcu_read_lock(&dev->disassociate_srcu);
1117         ib_dev = srcu_dereference(dev->ib_dev, &dev->disassociate_srcu);
1118         if (ib_dev)
1119                 ret = sprintf(buf, "%s\n", dev_name(&ib_dev->dev));
1120         srcu_read_unlock(&dev->disassociate_srcu, srcu_key);
1121
1122         return ret;
1123 }
1124 static DEVICE_ATTR_RO(ibdev);
1125
1126 static ssize_t abi_version_show(struct device *device,
1127                                 struct device_attribute *attr, char *buf)
1128 {
1129         struct ib_uverbs_device *dev =
1130                         container_of(device, struct ib_uverbs_device, dev);
1131         int ret = -ENODEV;
1132         int srcu_key;
1133         struct ib_device *ib_dev;
1134
1135         srcu_key = srcu_read_lock(&dev->disassociate_srcu);
1136         ib_dev = srcu_dereference(dev->ib_dev, &dev->disassociate_srcu);
1137         if (ib_dev)
1138                 ret = sprintf(buf, "%u\n", ib_dev->ops.uverbs_abi_ver);
1139         srcu_read_unlock(&dev->disassociate_srcu, srcu_key);
1140
1141         return ret;
1142 }
1143 static DEVICE_ATTR_RO(abi_version);
1144
1145 static struct attribute *ib_dev_attrs[] = {
1146         &dev_attr_abi_version.attr,
1147         &dev_attr_ibdev.attr,
1148         NULL,
1149 };
1150
1151 static const struct attribute_group dev_attr_group = {
1152         .attrs = ib_dev_attrs,
1153 };
1154
1155 static CLASS_ATTR_STRING(abi_version, S_IRUGO,
1156                          __stringify(IB_USER_VERBS_ABI_VERSION));
1157
1158 static int ib_uverbs_create_uapi(struct ib_device *device,
1159                                  struct ib_uverbs_device *uverbs_dev)
1160 {
1161         struct uverbs_api *uapi;
1162
1163         uapi = uverbs_alloc_api(device);
1164         if (IS_ERR(uapi))
1165                 return PTR_ERR(uapi);
1166
1167         uverbs_dev->uapi = uapi;
1168         return 0;
1169 }
1170
1171 static void ib_uverbs_add_one(struct ib_device *device)
1172 {
1173         int devnum;
1174         dev_t base;
1175         struct ib_uverbs_device *uverbs_dev;
1176         int ret;
1177
1178         if (!device->ops.alloc_ucontext)
1179                 return;
1180
1181         uverbs_dev = kzalloc(sizeof(*uverbs_dev), GFP_KERNEL);
1182         if (!uverbs_dev)
1183                 return;
1184
1185         ret = init_srcu_struct(&uverbs_dev->disassociate_srcu);
1186         if (ret) {
1187                 kfree(uverbs_dev);
1188                 return;
1189         }
1190
1191         device_initialize(&uverbs_dev->dev);
1192         uverbs_dev->dev.class = uverbs_class;
1193         uverbs_dev->dev.parent = device->dev.parent;
1194         uverbs_dev->dev.release = ib_uverbs_release_dev;
1195         uverbs_dev->groups[0] = &dev_attr_group;
1196         uverbs_dev->dev.groups = uverbs_dev->groups;
1197         atomic_set(&uverbs_dev->refcount, 1);
1198         init_completion(&uverbs_dev->comp);
1199         uverbs_dev->xrcd_tree = RB_ROOT;
1200         mutex_init(&uverbs_dev->xrcd_tree_mutex);
1201         mutex_init(&uverbs_dev->lists_mutex);
1202         INIT_LIST_HEAD(&uverbs_dev->uverbs_file_list);
1203         INIT_LIST_HEAD(&uverbs_dev->uverbs_events_file_list);
1204         rcu_assign_pointer(uverbs_dev->ib_dev, device);
1205         uverbs_dev->num_comp_vectors = device->num_comp_vectors;
1206
1207         devnum = ida_alloc_max(&uverbs_ida, IB_UVERBS_MAX_DEVICES - 1,
1208                                GFP_KERNEL);
1209         if (devnum < 0)
1210                 goto err;
1211         uverbs_dev->devnum = devnum;
1212         if (devnum >= IB_UVERBS_NUM_FIXED_MINOR)
1213                 base = dynamic_uverbs_dev + devnum - IB_UVERBS_NUM_FIXED_MINOR;
1214         else
1215                 base = IB_UVERBS_BASE_DEV + devnum;
1216
1217         if (ib_uverbs_create_uapi(device, uverbs_dev))
1218                 goto err_uapi;
1219
1220         uverbs_dev->dev.devt = base;
1221         dev_set_name(&uverbs_dev->dev, "uverbs%d", uverbs_dev->devnum);
1222
1223         cdev_init(&uverbs_dev->cdev,
1224                   device->ops.mmap ? &uverbs_mmap_fops : &uverbs_fops);
1225         uverbs_dev->cdev.owner = THIS_MODULE;
1226
1227         ret = cdev_device_add(&uverbs_dev->cdev, &uverbs_dev->dev);
1228         if (ret)
1229                 goto err_uapi;
1230
1231         ib_set_client_data(device, &uverbs_client, uverbs_dev);
1232         return;
1233
1234 err_uapi:
1235         ida_free(&uverbs_ida, devnum);
1236 err:
1237         if (atomic_dec_and_test(&uverbs_dev->refcount))
1238                 ib_uverbs_comp_dev(uverbs_dev);
1239         wait_for_completion(&uverbs_dev->comp);
1240         put_device(&uverbs_dev->dev);
1241         return;
1242 }
1243
1244 static void ib_uverbs_free_hw_resources(struct ib_uverbs_device *uverbs_dev,
1245                                         struct ib_device *ib_dev)
1246 {
1247         struct ib_uverbs_file *file;
1248         struct ib_uverbs_async_event_file *event_file;
1249         struct ib_event event;
1250
1251         /* Pending running commands to terminate */
1252         uverbs_disassociate_api_pre(uverbs_dev);
1253         event.event = IB_EVENT_DEVICE_FATAL;
1254         event.element.port_num = 0;
1255         event.device = ib_dev;
1256
1257         mutex_lock(&uverbs_dev->lists_mutex);
1258         while (!list_empty(&uverbs_dev->uverbs_file_list)) {
1259                 file = list_first_entry(&uverbs_dev->uverbs_file_list,
1260                                         struct ib_uverbs_file, list);
1261                 list_del_init(&file->list);
1262                 kref_get(&file->ref);
1263
1264                 /* We must release the mutex before going ahead and calling
1265                  * uverbs_cleanup_ufile, as it might end up indirectly calling
1266                  * uverbs_close, for example due to freeing the resources (e.g
1267                  * mmput).
1268                  */
1269                 mutex_unlock(&uverbs_dev->lists_mutex);
1270
1271                 ib_uverbs_event_handler(&file->event_handler, &event);
1272                 uverbs_destroy_ufile_hw(file, RDMA_REMOVE_DRIVER_REMOVE);
1273                 kref_put(&file->ref, ib_uverbs_release_file);
1274
1275                 mutex_lock(&uverbs_dev->lists_mutex);
1276         }
1277
1278         while (!list_empty(&uverbs_dev->uverbs_events_file_list)) {
1279                 event_file = list_first_entry(&uverbs_dev->
1280                                               uverbs_events_file_list,
1281                                               struct ib_uverbs_async_event_file,
1282                                               list);
1283                 spin_lock_irq(&event_file->ev_queue.lock);
1284                 event_file->ev_queue.is_closed = 1;
1285                 spin_unlock_irq(&event_file->ev_queue.lock);
1286
1287                 list_del(&event_file->list);
1288                 ib_unregister_event_handler(
1289                         &event_file->uverbs_file->event_handler);
1290                 event_file->uverbs_file->event_handler.device =
1291                         NULL;
1292
1293                 wake_up_interruptible(&event_file->ev_queue.poll_wait);
1294                 kill_fasync(&event_file->ev_queue.async_queue, SIGIO, POLL_IN);
1295         }
1296         mutex_unlock(&uverbs_dev->lists_mutex);
1297
1298         uverbs_disassociate_api(uverbs_dev->uapi);
1299 }
1300
1301 static void ib_uverbs_remove_one(struct ib_device *device, void *client_data)
1302 {
1303         struct ib_uverbs_device *uverbs_dev = client_data;
1304         int wait_clients = 1;
1305
1306         if (!uverbs_dev)
1307                 return;
1308
1309         cdev_device_del(&uverbs_dev->cdev, &uverbs_dev->dev);
1310         ida_free(&uverbs_ida, uverbs_dev->devnum);
1311
1312         if (device->ops.disassociate_ucontext) {
1313                 /* We disassociate HW resources and immediately return.
1314                  * Userspace will see a EIO errno for all future access.
1315                  * Upon returning, ib_device may be freed internally and is not
1316                  * valid any more.
1317                  * uverbs_device is still available until all clients close
1318                  * their files, then the uverbs device ref count will be zero
1319                  * and its resources will be freed.
1320                  * Note: At this point no more files can be opened since the
1321                  * cdev was deleted, however active clients can still issue
1322                  * commands and close their open files.
1323                  */
1324                 ib_uverbs_free_hw_resources(uverbs_dev, device);
1325                 wait_clients = 0;
1326         }
1327
1328         if (atomic_dec_and_test(&uverbs_dev->refcount))
1329                 ib_uverbs_comp_dev(uverbs_dev);
1330         if (wait_clients)
1331                 wait_for_completion(&uverbs_dev->comp);
1332
1333         put_device(&uverbs_dev->dev);
1334 }
1335
1336 static char *uverbs_devnode(struct device *dev, umode_t *mode)
1337 {
1338         if (mode)
1339                 *mode = 0666;
1340         return kasprintf(GFP_KERNEL, "infiniband/%s", dev_name(dev));
1341 }
1342
1343 static int __init ib_uverbs_init(void)
1344 {
1345         int ret;
1346
1347         ret = register_chrdev_region(IB_UVERBS_BASE_DEV,
1348                                      IB_UVERBS_NUM_FIXED_MINOR,
1349                                      "infiniband_verbs");
1350         if (ret) {
1351                 pr_err("user_verbs: couldn't register device number\n");
1352                 goto out;
1353         }
1354
1355         ret = alloc_chrdev_region(&dynamic_uverbs_dev, 0,
1356                                   IB_UVERBS_NUM_DYNAMIC_MINOR,
1357                                   "infiniband_verbs");
1358         if (ret) {
1359                 pr_err("couldn't register dynamic device number\n");
1360                 goto out_alloc;
1361         }
1362
1363         uverbs_class = class_create(THIS_MODULE, "infiniband_verbs");
1364         if (IS_ERR(uverbs_class)) {
1365                 ret = PTR_ERR(uverbs_class);
1366                 pr_err("user_verbs: couldn't create class infiniband_verbs\n");
1367                 goto out_chrdev;
1368         }
1369
1370         uverbs_class->devnode = uverbs_devnode;
1371
1372         ret = class_create_file(uverbs_class, &class_attr_abi_version.attr);
1373         if (ret) {
1374                 pr_err("user_verbs: couldn't create abi_version attribute\n");
1375                 goto out_class;
1376         }
1377
1378         ret = ib_register_client(&uverbs_client);
1379         if (ret) {
1380                 pr_err("user_verbs: couldn't register client\n");
1381                 goto out_class;
1382         }
1383
1384         return 0;
1385
1386 out_class:
1387         class_destroy(uverbs_class);
1388
1389 out_chrdev:
1390         unregister_chrdev_region(dynamic_uverbs_dev,
1391                                  IB_UVERBS_NUM_DYNAMIC_MINOR);
1392
1393 out_alloc:
1394         unregister_chrdev_region(IB_UVERBS_BASE_DEV,
1395                                  IB_UVERBS_NUM_FIXED_MINOR);
1396
1397 out:
1398         return ret;
1399 }
1400
1401 static void __exit ib_uverbs_cleanup(void)
1402 {
1403         ib_unregister_client(&uverbs_client);
1404         class_destroy(uverbs_class);
1405         unregister_chrdev_region(IB_UVERBS_BASE_DEV,
1406                                  IB_UVERBS_NUM_FIXED_MINOR);
1407         unregister_chrdev_region(dynamic_uverbs_dev,
1408                                  IB_UVERBS_NUM_DYNAMIC_MINOR);
1409         mmu_notifier_synchronize();
1410 }
1411
1412 module_init(ib_uverbs_init);
1413 module_exit(ib_uverbs_cleanup);