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
  49 #include <linux/uaccess.h>
  50
  51 #include <rdma/ib.h>
  52
  53 #include "uverbs.h"
  54 #include "core_priv.h"
  55 #include "rdma_core.h"
  56
  57 MODULE_AUTHOR("Roland Dreier");
  58 MODULE_DESCRIPTION("InfiniBand userspace verbs access");
  59 MODULE_LICENSE("Dual BSD/GPL");
  60
  61 enum {
  62         IB_UVERBS_MAJOR       = 231,
  63         IB_UVERBS_BASE_MINOR  = 192,
  64         IB_UVERBS_MAX_DEVICES = 32
  65 };
  66
  67 #define IB_UVERBS_BASE_DEV      MKDEV(IB_UVERBS_MAJOR, IB_UVERBS_BASE_MINOR)
  68
  69 static struct class *uverbs_class;
  70
  71 static DEFINE_SPINLOCK(map_lock);
  72 static DECLARE_BITMAP(dev_map, IB_UVERBS_MAX_DEVICES);
  73
  74 static ssize_t (*uverbs_cmd_table[])(struct ib_uverbs_file *file,
  75                                      struct ib_device *ib_dev,
  76                                      const char __user *buf, int in_len,
  77                                      int out_len) = {
  78         [IB_USER_VERBS_CMD_GET_CONTEXT]         = ib_uverbs_get_context,
  79         [IB_USER_VERBS_CMD_QUERY_DEVICE]        = ib_uverbs_query_device,
  80         [IB_USER_VERBS_CMD_QUERY_PORT]          = ib_uverbs_query_port,
  81         [IB_USER_VERBS_CMD_ALLOC_PD]            = ib_uverbs_alloc_pd,
  82         [IB_USER_VERBS_CMD_DEALLOC_PD]          = ib_uverbs_dealloc_pd,
  83         [IB_USER_VERBS_CMD_REG_MR]              = ib_uverbs_reg_mr,
  84         [IB_USER_VERBS_CMD_REREG_MR]            = ib_uverbs_rereg_mr,
  85         [IB_USER_VERBS_CMD_DEREG_MR]            = ib_uverbs_dereg_mr,
  86         [IB_USER_VERBS_CMD_ALLOC_MW]            = ib_uverbs_alloc_mw,
  87         [IB_USER_VERBS_CMD_DEALLOC_MW]          = ib_uverbs_dealloc_mw,
  88         [IB_USER_VERBS_CMD_CREATE_COMP_CHANNEL] = ib_uverbs_create_comp_channel,
  89         [IB_USER_VERBS_CMD_CREATE_CQ]           = ib_uverbs_create_cq,
  90         [IB_USER_VERBS_CMD_RESIZE_CQ]           = ib_uverbs_resize_cq,
  91         [IB_USER_VERBS_CMD_POLL_CQ]             = ib_uverbs_poll_cq,
  92         [IB_USER_VERBS_CMD_REQ_NOTIFY_CQ]       = ib_uverbs_req_notify_cq,
  93         [IB_USER_VERBS_CMD_DESTROY_CQ]          = ib_uverbs_destroy_cq,
  94         [IB_USER_VERBS_CMD_CREATE_QP]           = ib_uverbs_create_qp,
  95         [IB_USER_VERBS_CMD_QUERY_QP]            = ib_uverbs_query_qp,
  96         [IB_USER_VERBS_CMD_MODIFY_QP]           = ib_uverbs_modify_qp,
  97         [IB_USER_VERBS_CMD_DESTROY_QP]          = ib_uverbs_destroy_qp,
  98         [IB_USER_VERBS_CMD_POST_SEND]           = ib_uverbs_post_send,
  99         [IB_USER_VERBS_CMD_POST_RECV]           = ib_uverbs_post_recv,
 100         [IB_USER_VERBS_CMD_POST_SRQ_RECV]       = ib_uverbs_post_srq_recv,
 101         [IB_USER_VERBS_CMD_CREATE_AH]           = ib_uverbs_create_ah,
 102         [IB_USER_VERBS_CMD_DESTROY_AH]          = ib_uverbs_destroy_ah,
 103         [IB_USER_VERBS_CMD_ATTACH_MCAST]        = ib_uverbs_attach_mcast,
 104         [IB_USER_VERBS_CMD_DETACH_MCAST]        = ib_uverbs_detach_mcast,
 105         [IB_USER_VERBS_CMD_CREATE_SRQ]          = ib_uverbs_create_srq,
 106         [IB_USER_VERBS_CMD_MODIFY_SRQ]          = ib_uverbs_modify_srq,
 107         [IB_USER_VERBS_CMD_QUERY_SRQ]           = ib_uverbs_query_srq,
 108         [IB_USER_VERBS_CMD_DESTROY_SRQ]         = ib_uverbs_destroy_srq,
 109         [IB_USER_VERBS_CMD_OPEN_XRCD]           = ib_uverbs_open_xrcd,
 110         [IB_USER_VERBS_CMD_CLOSE_XRCD]          = ib_uverbs_close_xrcd,
 111         [IB_USER_VERBS_CMD_CREATE_XSRQ]         = ib_uverbs_create_xsrq,
 112         [IB_USER_VERBS_CMD_OPEN_QP]             = ib_uverbs_open_qp,
 113 };
 114
 115 static int (*uverbs_ex_cmd_table[])(struct ib_uverbs_file *file,
 116                                     struct ib_device *ib_dev,
 117                                     struct ib_udata *ucore,
 118                                     struct ib_udata *uhw) = {
 119         [IB_USER_VERBS_EX_CMD_CREATE_FLOW]      = ib_uverbs_ex_create_flow,
 120         [IB_USER_VERBS_EX_CMD_DESTROY_FLOW]     = ib_uverbs_ex_destroy_flow,
 121         [IB_USER_VERBS_EX_CMD_QUERY_DEVICE]     = ib_uverbs_ex_query_device,
 122         [IB_USER_VERBS_EX_CMD_CREATE_CQ]        = ib_uverbs_ex_create_cq,
 123         [IB_USER_VERBS_EX_CMD_CREATE_QP]        = ib_uverbs_ex_create_qp,
 124         [IB_USER_VERBS_EX_CMD_CREATE_WQ]        = ib_uverbs_ex_create_wq,
 125         [IB_USER_VERBS_EX_CMD_MODIFY_WQ]        = ib_uverbs_ex_modify_wq,
 126         [IB_USER_VERBS_EX_CMD_DESTROY_WQ]       = ib_uverbs_ex_destroy_wq,
 127         [IB_USER_VERBS_EX_CMD_CREATE_RWQ_IND_TBL] = ib_uverbs_ex_create_rwq_ind_table,
 128         [IB_USER_VERBS_EX_CMD_DESTROY_RWQ_IND_TBL] = ib_uverbs_ex_destroy_rwq_ind_table,
 129         [IB_USER_VERBS_EX_CMD_MODIFY_QP]        = ib_uverbs_ex_modify_qp,
 130 };
 131
 132 static void ib_uverbs_add_one(struct ib_device *device);
 133 static void ib_uverbs_remove_one(struct ib_device *device, void *client_data);
 134
 135 int uverbs_dealloc_mw(struct ib_mw *mw)
 136 {
 137         struct ib_pd *pd = mw->pd;
 138         int ret;
 139
 140         ret = mw->device->dealloc_mw(mw);
 141         if (!ret)
 142                 atomic_dec(&pd->usecnt);
 143         return ret;
 144 }
 145
 146 static void ib_uverbs_release_dev(struct kobject *kobj)
 147 {
 148         struct ib_uverbs_device *dev =
 149                 container_of(kobj, struct ib_uverbs_device, kobj);
 150
 151         cleanup_srcu_struct(&dev->disassociate_srcu);
 152         kfree(dev);
 153 }
 154
 155 static struct kobj_type ib_uverbs_dev_ktype = {
 156         .release = ib_uverbs_release_dev,
 157 };
 158
 159 static void ib_uverbs_release_async_event_file(struct kref *ref)
 160 {
 161         struct ib_uverbs_async_event_file *file =
 162                 container_of(ref, struct ib_uverbs_async_event_file, ref);
 163
 164         kfree(file);
 165 }
 166
 167 void ib_uverbs_release_ucq(struct ib_uverbs_file *file,
 168                           struct ib_uverbs_completion_event_file *ev_file,
 169                           struct ib_ucq_object *uobj)
 170 {
 171         struct ib_uverbs_event *evt, *tmp;
 172
 173         if (ev_file) {
 174                 spin_lock_irq(&ev_file->ev_queue.lock);
 175                 list_for_each_entry_safe(evt, tmp, &uobj->comp_list, obj_list) {
 176                         list_del(&evt->list);
 177                         kfree(evt);
 178                 }
 179                 spin_unlock_irq(&ev_file->ev_queue.lock);
 180
 181                 uverbs_uobject_put(&ev_file->uobj_file.uobj);
 182         }
 183
 184         spin_lock_irq(&file->async_file->ev_queue.lock);
 185         list_for_each_entry_safe(evt, tmp, &uobj->async_list, obj_list) {
 186                 list_del(&evt->list);
 187                 kfree(evt);
 188         }
 189         spin_unlock_irq(&file->async_file->ev_queue.lock);
 190 }
 191
 192 void ib_uverbs_release_uevent(struct ib_uverbs_file *file,
 193                               struct ib_uevent_object *uobj)
 194 {
 195         struct ib_uverbs_event *evt, *tmp;
 196
 197         spin_lock_irq(&file->async_file->ev_queue.lock);
 198         list_for_each_entry_safe(evt, tmp, &uobj->event_list, obj_list) {
 199                 list_del(&evt->list);
 200                 kfree(evt);
 201         }
 202         spin_unlock_irq(&file->async_file->ev_queue.lock);
 203 }
 204
 205 void ib_uverbs_detach_umcast(struct ib_qp *qp,
 206                              struct ib_uqp_object *uobj)
 207 {
 208         struct ib_uverbs_mcast_entry *mcast, *tmp;
 209
 210         list_for_each_entry_safe(mcast, tmp, &uobj->mcast_list, list) {
 211                 ib_detach_mcast(qp, &mcast->gid, mcast->lid);
 212                 list_del(&mcast->list);
 213                 kfree(mcast);
 214         }
 215 }
 216
 217 static int ib_uverbs_cleanup_ucontext(struct ib_uverbs_file *file,
 218                                       struct ib_ucontext *context,
 219                                       bool device_removed)
 220 {
 221         context->closing = 1;
 222         uverbs_cleanup_ucontext(context, device_removed);
 223         put_pid(context->tgid);
 224
 225         ib_rdmacg_uncharge(&context->cg_obj, context->device,
 226                            RDMACG_RESOURCE_HCA_HANDLE);
 227
 228         return context->device->dealloc_ucontext(context);
 229 }
 230
 231 static void ib_uverbs_comp_dev(struct ib_uverbs_device *dev)
 232 {
 233         complete(&dev->comp);
 234 }
 235
 236 void ib_uverbs_release_file(struct kref *ref)
 237 {
 238         struct ib_uverbs_file *file =
 239                 container_of(ref, struct ib_uverbs_file, ref);
 240         struct ib_device *ib_dev;
 241         int srcu_key;
 242
 243         srcu_key = srcu_read_lock(&file->device->disassociate_srcu);
 244         ib_dev = srcu_dereference(file->device->ib_dev,
 245                                   &file->device->disassociate_srcu);
 246         if (ib_dev && !ib_dev->disassociate_ucontext)
 247                 module_put(ib_dev->owner);
 248         srcu_read_unlock(&file->device->disassociate_srcu, srcu_key);
 249
 250         if (atomic_dec_and_test(&file->device->refcount))
 251                 ib_uverbs_comp_dev(file->device);
 252
 253         kfree(file);
 254 }
 255
 256 static ssize_t ib_uverbs_event_read(struct ib_uverbs_event_queue *ev_queue,
 257                                     struct ib_uverbs_file *uverbs_file,
 258                                     struct file *filp, char __user *buf,
 259                                     size_t count, loff_t *pos,
 260                                     size_t eventsz)
 261 {
 262         struct ib_uverbs_event *event;
 263         int ret = 0;
 264
 265         spin_lock_irq(&ev_queue->lock);
 266
 267         while (list_empty(&ev_queue->event_list)) {
 268                 spin_unlock_irq(&ev_queue->lock);
 269
 270                 if (filp->f_flags & O_NONBLOCK)
 271                         return -EAGAIN;
 272
 273                 if (wait_event_interruptible(ev_queue->poll_wait,
 274                                              (!list_empty(&ev_queue->event_list) ||
 275                         /* The barriers built into wait_event_interruptible()
 276                          * and wake_up() guarentee this will see the null set
 277                          * without using RCU
 278                          */
 279                                              !uverbs_file->device->ib_dev)))
 280                         return -ERESTARTSYS;
 281
 282                 /* If device was disassociated and no event exists set an error */
 283                 if (list_empty(&ev_queue->event_list) &&
 284                     !uverbs_file->device->ib_dev)
 285                         return -EIO;
 286
 287                 spin_lock_irq(&ev_queue->lock);
 288         }
 289
 290         event = list_entry(ev_queue->event_list.next, struct ib_uverbs_event, list);
 291
 292         if (eventsz > count) {
 293                 ret   = -EINVAL;
 294                 event = NULL;
 295         } else {
 296                 list_del(ev_queue->event_list.next);
 297                 if (event->counter) {
 298                         ++(*event->counter);
 299                         list_del(&event->obj_list);
 300                 }
 301         }
 302
 303         spin_unlock_irq(&ev_queue->lock);
 304
 305         if (event) {
 306                 if (copy_to_user(buf, event, eventsz))
 307                         ret = -EFAULT;
 308                 else
 309                         ret = eventsz;
 310         }
 311
 312         kfree(event);
 313
 314         return ret;
 315 }
 316
 317 static ssize_t ib_uverbs_async_event_read(struct file *filp, char __user *buf,
 318                                           size_t count, loff_t *pos)
 319 {
 320         struct ib_uverbs_async_event_file *file = filp->private_data;
 321
 322         return ib_uverbs_event_read(&file->ev_queue, file->uverbs_file, filp,
 323                                     buf, count, pos,
 324                                     sizeof(struct ib_uverbs_async_event_desc));
 325 }
 326
 327 static ssize_t ib_uverbs_comp_event_read(struct file *filp, char __user *buf,
 328                                          size_t count, loff_t *pos)
 329 {
 330         struct ib_uverbs_completion_event_file *comp_ev_file =
 331                 filp->private_data;
 332
 333         return ib_uverbs_event_read(&comp_ev_file->ev_queue,
 334                                     comp_ev_file->uobj_file.ufile, filp,
 335                                     buf, count, pos,
 336                                     sizeof(struct ib_uverbs_comp_event_desc));
 337 }
 338
 339 static unsigned int ib_uverbs_event_poll(struct ib_uverbs_event_queue *ev_queue,
 340                                          struct file *filp,
 341                                          struct poll_table_struct *wait)
 342 {
 343         unsigned int pollflags = 0;
 344
 345         poll_wait(filp, &ev_queue->poll_wait, wait);
 346
 347         spin_lock_irq(&ev_queue->lock);
 348         if (!list_empty(&ev_queue->event_list))
 349                 pollflags = POLLIN | POLLRDNORM;
 350         spin_unlock_irq(&ev_queue->lock);
 351
 352         return pollflags;
 353 }
 354
 355 static unsigned int ib_uverbs_async_event_poll(struct file *filp,
 356                                                struct poll_table_struct *wait)
 357 {
 358         return ib_uverbs_event_poll(filp->private_data, filp, wait);
 359 }
 360
 361 static unsigned int ib_uverbs_comp_event_poll(struct file *filp,
 362                                               struct poll_table_struct *wait)
 363 {
 364         struct ib_uverbs_completion_event_file *comp_ev_file =
 365                 filp->private_data;
 366
 367         return ib_uverbs_event_poll(&comp_ev_file->ev_queue, filp, wait);
 368 }
 369
 370 static int ib_uverbs_async_event_fasync(int fd, struct file *filp, int on)
 371 {
 372         struct ib_uverbs_event_queue *ev_queue = filp->private_data;
 373
 374         return fasync_helper(fd, filp, on, &ev_queue->async_queue);
 375 }
 376
 377 static int ib_uverbs_comp_event_fasync(int fd, struct file *filp, int on)
 378 {
 379         struct ib_uverbs_completion_event_file *comp_ev_file =
 380                 filp->private_data;
 381
 382         return fasync_helper(fd, filp, on, &comp_ev_file->ev_queue.async_queue);
 383 }
 384
 385 static int ib_uverbs_async_event_close(struct inode *inode, struct file *filp)
 386 {
 387         struct ib_uverbs_async_event_file *file = filp->private_data;
 388         struct ib_uverbs_file *uverbs_file = file->uverbs_file;
 389         struct ib_uverbs_event *entry, *tmp;
 390         int closed_already = 0;
 391
 392         mutex_lock(&uverbs_file->device->lists_mutex);
 393         spin_lock_irq(&file->ev_queue.lock);
 394         closed_already = file->ev_queue.is_closed;
 395         file->ev_queue.is_closed = 1;
 396         list_for_each_entry_safe(entry, tmp, &file->ev_queue.event_list, list) {
 397                 if (entry->counter)
 398                         list_del(&entry->obj_list);
 399                 kfree(entry);
 400         }
 401         spin_unlock_irq(&file->ev_queue.lock);
 402         if (!closed_already) {
 403                 list_del(&file->list);
 404                 ib_unregister_event_handler(&uverbs_file->event_handler);
 405         }
 406         mutex_unlock(&uverbs_file->device->lists_mutex);
 407
 408         kref_put(&uverbs_file->ref, ib_uverbs_release_file);
 409         kref_put(&file->ref, ib_uverbs_release_async_event_file);
 410
 411         return 0;
 412 }
 413
 414 static int ib_uverbs_comp_event_close(struct inode *inode, struct file *filp)
 415 {
 416         struct ib_uverbs_completion_event_file *file = filp->private_data;
 417         struct ib_uverbs_event *entry, *tmp;
 418
 419         spin_lock_irq(&file->ev_queue.lock);
 420         list_for_each_entry_safe(entry, tmp, &file->ev_queue.event_list, list) {
 421                 if (entry->counter)
 422                         list_del(&entry->obj_list);
 423                 kfree(entry);
 424         }
 425         spin_unlock_irq(&file->ev_queue.lock);
 426
 427         uverbs_close_fd(filp);
 428
 429         return 0;
 430 }
 431
 432 const struct file_operations uverbs_event_fops = {
 433         .owner   = THIS_MODULE,
 434         .read    = ib_uverbs_comp_event_read,
 435         .poll    = ib_uverbs_comp_event_poll,
 436         .release = ib_uverbs_comp_event_close,
 437         .fasync  = ib_uverbs_comp_event_fasync,
 438         .llseek  = no_llseek,
 439 };
 440
 441 static const struct file_operations uverbs_async_event_fops = {
 442         .owner   = THIS_MODULE,
 443         .read    = ib_uverbs_async_event_read,
 444         .poll    = ib_uverbs_async_event_poll,
 445         .release = ib_uverbs_async_event_close,
 446         .fasync  = ib_uverbs_async_event_fasync,
 447         .llseek  = no_llseek,
 448 };
 449
 450 void ib_uverbs_comp_handler(struct ib_cq *cq, void *cq_context)
 451 {
 452         struct ib_uverbs_event_queue   *ev_queue = cq_context;
 453         struct ib_ucq_object           *uobj;
 454         struct ib_uverbs_event         *entry;
 455         unsigned long                   flags;
 456
 457         if (!ev_queue)
 458                 return;
 459
 460         spin_lock_irqsave(&ev_queue->lock, flags);
 461         if (ev_queue->is_closed) {
 462                 spin_unlock_irqrestore(&ev_queue->lock, flags);
 463                 return;
 464         }
 465
 466         entry = kmalloc(sizeof *entry, GFP_ATOMIC);
 467         if (!entry) {
 468                 spin_unlock_irqrestore(&ev_queue->lock, flags);
 469                 return;
 470         }
 471
 472         uobj = container_of(cq->uobject, struct ib_ucq_object, uobject);
 473
 474         entry->desc.comp.cq_handle = cq->uobject->user_handle;
 475         entry->counter             = &uobj->comp_events_reported;
 476
 477         list_add_tail(&entry->list, &ev_queue->event_list);
 478         list_add_tail(&entry->obj_list, &uobj->comp_list);
 479         spin_unlock_irqrestore(&ev_queue->lock, flags);
 480
 481         wake_up_interruptible(&ev_queue->poll_wait);
 482         kill_fasync(&ev_queue->async_queue, SIGIO, POLL_IN);
 483 }
 484
 485 static void ib_uverbs_async_handler(struct ib_uverbs_file *file,
 486                                     __u64 element, __u64 event,
 487                                     struct list_head *obj_list,
 488                                     u32 *counter)
 489 {
 490         struct ib_uverbs_event *entry;
 491         unsigned long flags;
 492
 493         spin_lock_irqsave(&file->async_file->ev_queue.lock, flags);
 494         if (file->async_file->ev_queue.is_closed) {
 495                 spin_unlock_irqrestore(&file->async_file->ev_queue.lock, flags);
 496                 return;
 497         }
 498
 499         entry = kmalloc(sizeof *entry, GFP_ATOMIC);
 500         if (!entry) {
 501                 spin_unlock_irqrestore(&file->async_file->ev_queue.lock, flags);
 502                 return;
 503         }
 504
 505         entry->desc.async.element    = element;
 506         entry->desc.async.event_type = event;
 507         entry->desc.async.reserved   = 0;
 508         entry->counter               = counter;
 509
 510         list_add_tail(&entry->list, &file->async_file->ev_queue.event_list);
 511         if (obj_list)
 512                 list_add_tail(&entry->obj_list, obj_list);
 513         spin_unlock_irqrestore(&file->async_file->ev_queue.lock, flags);
 514
 515         wake_up_interruptible(&file->async_file->ev_queue.poll_wait);
 516         kill_fasync(&file->async_file->ev_queue.async_queue, SIGIO, POLL_IN);
 517 }
 518
 519 void ib_uverbs_cq_event_handler(struct ib_event *event, void *context_ptr)
 520 {
 521         struct ib_ucq_object *uobj = container_of(event->element.cq->uobject,
 522                                                   struct ib_ucq_object, uobject);
 523
 524         ib_uverbs_async_handler(uobj->uverbs_file, uobj->uobject.user_handle,
 525                                 event->event, &uobj->async_list,
 526                                 &uobj->async_events_reported);
 527 }
 528
 529 void ib_uverbs_qp_event_handler(struct ib_event *event, void *context_ptr)
 530 {
 531         struct ib_uevent_object *uobj;
 532
 533         /* for XRC target qp's, check that qp is live */
 534         if (!event->element.qp->uobject)
 535                 return;
 536
 537         uobj = container_of(event->element.qp->uobject,
 538                             struct ib_uevent_object, uobject);
 539
 540         ib_uverbs_async_handler(context_ptr, uobj->uobject.user_handle,
 541                                 event->event, &uobj->event_list,
 542                                 &uobj->events_reported);
 543 }
 544
 545 void ib_uverbs_wq_event_handler(struct ib_event *event, void *context_ptr)
 546 {
 547         struct ib_uevent_object *uobj = container_of(event->element.wq->uobject,
 548                                                   struct ib_uevent_object, uobject);
 549
 550         ib_uverbs_async_handler(context_ptr, uobj->uobject.user_handle,
 551                                 event->event, &uobj->event_list,
 552                                 &uobj->events_reported);
 553 }
 554
 555 void ib_uverbs_srq_event_handler(struct ib_event *event, void *context_ptr)
 556 {
 557         struct ib_uevent_object *uobj;
 558
 559         uobj = container_of(event->element.srq->uobject,
 560                             struct ib_uevent_object, uobject);
 561
 562         ib_uverbs_async_handler(context_ptr, uobj->uobject.user_handle,
 563                                 event->event, &uobj->event_list,
 564                                 &uobj->events_reported);
 565 }
 566
 567 void ib_uverbs_event_handler(struct ib_event_handler *handler,
 568                              struct ib_event *event)
 569 {
 570         struct ib_uverbs_file *file =
 571                 container_of(handler, struct ib_uverbs_file, event_handler);
 572
 573         ib_uverbs_async_handler(file, event->element.port_num, event->event,
 574                                 NULL, NULL);
 575 }
 576
 577 void ib_uverbs_free_async_event_file(struct ib_uverbs_file *file)
 578 {
 579         kref_put(&file->async_file->ref, ib_uverbs_release_async_event_file);
 580         file->async_file = NULL;
 581 }
 582
 583 void ib_uverbs_init_event_queue(struct ib_uverbs_event_queue *ev_queue)
 584 {
 585         spin_lock_init(&ev_queue->lock);
 586         INIT_LIST_HEAD(&ev_queue->event_list);
 587         init_waitqueue_head(&ev_queue->poll_wait);
 588         ev_queue->is_closed   = 0;
 589         ev_queue->async_queue = NULL;
 590 }
 591
 592 struct file *ib_uverbs_alloc_async_event_file(struct ib_uverbs_file *uverbs_file,
 593                                               struct ib_device  *ib_dev)
 594 {
 595         struct ib_uverbs_async_event_file *ev_file;
 596         struct file *filp;
 597         int ret;
 598
 599         ev_file = kzalloc(sizeof(*ev_file), GFP_KERNEL);
 600         if (!ev_file)
 601                 return ERR_PTR(-ENOMEM);
 602
 603         ib_uverbs_init_event_queue(&ev_file->ev_queue);
 604         ev_file->uverbs_file = uverbs_file;
 605         kref_get(&ev_file->uverbs_file->ref);
 606         kref_init(&ev_file->ref);
 607         filp = anon_inode_getfile("[infinibandevent]", &uverbs_async_event_fops,
 608                                   ev_file, O_RDONLY);
 609         if (IS_ERR(filp))
 610                 goto err_put_refs;
 611
 612         mutex_lock(&uverbs_file->device->lists_mutex);
 613         list_add_tail(&ev_file->list,
 614                       &uverbs_file->device->uverbs_events_file_list);
 615         mutex_unlock(&uverbs_file->device->lists_mutex);
 616
 617         WARN_ON(uverbs_file->async_file);
 618         uverbs_file->async_file = ev_file;
 619         kref_get(&uverbs_file->async_file->ref);
 620         INIT_IB_EVENT_HANDLER(&uverbs_file->event_handler,
 621                               ib_dev,
 622                               ib_uverbs_event_handler);
 623         ret = ib_register_event_handler(&uverbs_file->event_handler);
 624         if (ret)
 625                 goto err_put_file;
 626
 627         /* At that point async file stuff was fully set */
 628
 629         return filp;
 630
 631 err_put_file:
 632         fput(filp);
 633         kref_put(&uverbs_file->async_file->ref,
 634                  ib_uverbs_release_async_event_file);
 635         uverbs_file->async_file = NULL;
 636         return ERR_PTR(ret);
 637
 638 err_put_refs:
 639         kref_put(&ev_file->uverbs_file->ref, ib_uverbs_release_file);
 640         kref_put(&ev_file->ref, ib_uverbs_release_async_event_file);
 641         return filp;
 642 }
 643
 644 static int verify_command_mask(struct ib_device *ib_dev, __u32 command)
 645 {
 646         u64 mask;
 647
 648         if (command <= IB_USER_VERBS_CMD_OPEN_QP)
 649                 mask = ib_dev->uverbs_cmd_mask;
 650         else
 651                 mask = ib_dev->uverbs_ex_cmd_mask;
 652
 653         if (mask & ((u64)1 << command))
 654                 return 0;
 655
 656         return -1;
 657 }
 658
 659 static ssize_t ib_uverbs_write(struct file *filp, const char __user *buf,
 660                              size_t count, loff_t *pos)
 661 {
 662         struct ib_uverbs_file *file = filp->private_data;
 663         struct ib_device *ib_dev;
 664         struct ib_uverbs_cmd_hdr hdr;
 665         __u32 command;
 666         __u32 flags;
 667         int srcu_key;
 668         ssize_t ret;
 669
 670         if (!ib_safe_file_access(filp)) {
 671                 pr_err_once("uverbs_write: process %d (%s) changed security contexts after opening file descriptor, this is not allowed.\n",
 672                             task_tgid_vnr(current), current->comm);
 673                 return -EACCES;
 674         }
 675
 676         if (count < sizeof hdr)
 677                 return -EINVAL;
 678
 679         if (copy_from_user(&hdr, buf, sizeof hdr))
 680                 return -EFAULT;
 681
 682         srcu_key = srcu_read_lock(&file->device->disassociate_srcu);
 683         ib_dev = srcu_dereference(file->device->ib_dev,
 684                                   &file->device->disassociate_srcu);
 685         if (!ib_dev) {
 686                 ret = -EIO;
 687                 goto out;
 688         }
 689
 690         if (hdr.command & ~(__u32)(IB_USER_VERBS_CMD_FLAGS_MASK |
 691                                    IB_USER_VERBS_CMD_COMMAND_MASK)) {
 692                 ret = -EINVAL;
 693                 goto out;
 694         }
 695
 696         command = hdr.command & IB_USER_VERBS_CMD_COMMAND_MASK;
 697         if (verify_command_mask(ib_dev, command)) {
 698                 ret = -EOPNOTSUPP;
 699                 goto out;
 700         }
 701
 702         if (!file->ucontext &&
 703             command != IB_USER_VERBS_CMD_GET_CONTEXT) {
 704                 ret = -EINVAL;
 705                 goto out;
 706         }
 707
 708         flags = (hdr.command &
 709                  IB_USER_VERBS_CMD_FLAGS_MASK) >> IB_USER_VERBS_CMD_FLAGS_SHIFT;
 710
 711         if (!flags) {
 712                 if (command >= ARRAY_SIZE(uverbs_cmd_table) ||
 713                     !uverbs_cmd_table[command]) {
 714                         ret = -EINVAL;
 715                         goto out;
 716                 }
 717
 718                 if (hdr.in_words * 4 != count) {
 719                         ret = -EINVAL;
 720                         goto out;
 721                 }
 722
 723                 ret = uverbs_cmd_table[command](file, ib_dev,
 724                                                  buf + sizeof(hdr),
 725                                                  hdr.in_words * 4,
 726                                                  hdr.out_words * 4);
 727
 728         } else if (flags == IB_USER_VERBS_CMD_FLAG_EXTENDED) {
 729                 struct ib_uverbs_ex_cmd_hdr ex_hdr;
 730                 struct ib_udata ucore;
 731                 struct ib_udata uhw;
 732                 size_t written_count = count;
 733
 734                 if (command >= ARRAY_SIZE(uverbs_ex_cmd_table) ||
 735                     !uverbs_ex_cmd_table[command]) {
 736                         ret = -ENOSYS;
 737                         goto out;
 738                 }
 739
 740                 if (!file->ucontext) {
 741                         ret = -EINVAL;
 742                         goto out;
 743                 }
 744
 745                 if (count < (sizeof(hdr) + sizeof(ex_hdr))) {
 746                         ret = -EINVAL;
 747                         goto out;
 748                 }
 749
 750                 if (copy_from_user(&ex_hdr, buf + sizeof(hdr), sizeof(ex_hdr))) {
 751                         ret = -EFAULT;
 752                         goto out;
 753                 }
 754
 755                 count -= sizeof(hdr) + sizeof(ex_hdr);
 756                 buf += sizeof(hdr) + sizeof(ex_hdr);
 757
 758                 if ((hdr.in_words + ex_hdr.provider_in_words) * 8 != count) {
 759                         ret = -EINVAL;
 760                         goto out;
 761                 }
 762
 763                 if (ex_hdr.cmd_hdr_reserved) {
 764                         ret = -EINVAL;
 765                         goto out;
 766                 }
 767
 768                 if (ex_hdr.response) {
 769                         if (!hdr.out_words && !ex_hdr.provider_out_words) {
 770                                 ret = -EINVAL;
 771                                 goto out;
 772                         }
 773
 774                         if (!access_ok(VERIFY_WRITE,
 775                                        (void __user *) (unsigned long) ex_hdr.response,
 776                                        (hdr.out_words + ex_hdr.provider_out_words) * 8)) {
 777                                 ret = -EFAULT;
 778                                 goto out;
 779                         }
 780                 } else {
 781                         if (hdr.out_words || ex_hdr.provider_out_words) {
 782                                 ret = -EINVAL;
 783                                 goto out;
 784                         }
 785                 }
 786
 787                 INIT_UDATA_BUF_OR_NULL(&ucore, buf, (unsigned long) ex_hdr.response,
 788                                        hdr.in_words * 8, hdr.out_words * 8);
 789
 790                 INIT_UDATA_BUF_OR_NULL(&uhw,
 791                                        buf + ucore.inlen,
 792                                        (unsigned long) ex_hdr.response + ucore.outlen,
 793                                        ex_hdr.provider_in_words * 8,
 794                                        ex_hdr.provider_out_words * 8);
 795
 796                 ret = uverbs_ex_cmd_table[command](file,
 797                                                    ib_dev,
 798                                                    &ucore,
 799                                                    &uhw);
 800                 if (!ret)
 801                         ret = written_count;
 802         } else {
 803                 ret = -ENOSYS;
 804         }
 805
 806 out:
 807         srcu_read_unlock(&file->device->disassociate_srcu, srcu_key);
 808         return ret;
 809 }
 810
 811 static int ib_uverbs_mmap(struct file *filp, struct vm_area_struct *vma)
 812 {
 813         struct ib_uverbs_file *file = filp->private_data;
 814         struct ib_device *ib_dev;
 815         int ret = 0;
 816         int srcu_key;
 817
 818         srcu_key = srcu_read_lock(&file->device->disassociate_srcu);
 819         ib_dev = srcu_dereference(file->device->ib_dev,
 820                                   &file->device->disassociate_srcu);
 821         if (!ib_dev) {
 822                 ret = -EIO;
 823                 goto out;
 824         }
 825
 826         if (!file->ucontext)
 827                 ret = -ENODEV;
 828         else
 829                 ret = ib_dev->mmap(file->ucontext, vma);
 830 out:
 831         srcu_read_unlock(&file->device->disassociate_srcu, srcu_key);
 832         return ret;
 833 }
 834
 835 /*
 836  * ib_uverbs_open() does not need the BKL:
 837  *
 838  *  - the ib_uverbs_device structures are properly reference counted and
 839  *    everything else is purely local to the file being created, so
 840  *    races against other open calls are not a problem;
 841  *  - there is no ioctl method to race against;
 842  *  - the open method will either immediately run -ENXIO, or all
 843  *    required initialization will be done.
 844  */
 845 static int ib_uverbs_open(struct inode *inode, struct file *filp)
 846 {
 847         struct ib_uverbs_device *dev;
 848         struct ib_uverbs_file *file;
 849         struct ib_device *ib_dev;
 850         int ret;
 851         int module_dependent;
 852         int srcu_key;
 853
 854         dev = container_of(inode->i_cdev, struct ib_uverbs_device, cdev);
 855         if (!atomic_inc_not_zero(&dev->refcount))
 856                 return -ENXIO;
 857
 858         srcu_key = srcu_read_lock(&dev->disassociate_srcu);
 859         mutex_lock(&dev->lists_mutex);
 860         ib_dev = srcu_dereference(dev->ib_dev,
 861                                   &dev->disassociate_srcu);
 862         if (!ib_dev) {
 863                 ret = -EIO;
 864                 goto err;
 865         }
 866
 867         /* In case IB device supports disassociate ucontext, there is no hard
 868          * dependency between uverbs device and its low level device.
 869          */
 870         module_dependent = !(ib_dev->disassociate_ucontext);
 871
 872         if (module_dependent) {
 873                 if (!try_module_get(ib_dev->owner)) {
 874                         ret = -ENODEV;
 875                         goto err;
 876                 }
 877         }
 878
 879         file = kzalloc(sizeof(*file), GFP_KERNEL);
 880         if (!file) {
 881                 ret = -ENOMEM;
 882                 if (module_dependent)
 883                         goto err_module;
 884
 885                 goto err;
 886         }
 887
 888         file->device     = dev;
 889         spin_lock_init(&file->idr_lock);
 890         idr_init(&file->idr);
 891         file->ucontext   = NULL;
 892         file->async_file = NULL;
 893         kref_init(&file->ref);
 894         mutex_init(&file->mutex);
 895         mutex_init(&file->cleanup_mutex);
 896
 897         filp->private_data = file;
 898         kobject_get(&dev->kobj);
 899         list_add_tail(&file->list, &dev->uverbs_file_list);
 900         mutex_unlock(&dev->lists_mutex);
 901         srcu_read_unlock(&dev->disassociate_srcu, srcu_key);
 902
 903         return nonseekable_open(inode, filp);
 904
 905 err_module:
 906         module_put(ib_dev->owner);
 907
 908 err:
 909         mutex_unlock(&dev->lists_mutex);
 910         srcu_read_unlock(&dev->disassociate_srcu, srcu_key);
 911         if (atomic_dec_and_test(&dev->refcount))
 912                 ib_uverbs_comp_dev(dev);
 913
 914         return ret;
 915 }
 916
 917 static int ib_uverbs_close(struct inode *inode, struct file *filp)
 918 {
 919         struct ib_uverbs_file *file = filp->private_data;
 920         struct ib_uverbs_device *dev = file->device;
 921
 922         mutex_lock(&file->cleanup_mutex);
 923         if (file->ucontext) {
 924                 ib_uverbs_cleanup_ucontext(file, file->ucontext, false);
 925                 file->ucontext = NULL;
 926         }
 927         mutex_unlock(&file->cleanup_mutex);
 928         idr_destroy(&file->idr);
 929
 930         mutex_lock(&file->device->lists_mutex);
 931         if (!file->is_closed) {
 932                 list_del(&file->list);
 933                 file->is_closed = 1;
 934         }
 935         mutex_unlock(&file->device->lists_mutex);
 936
 937         if (file->async_file)
 938                 kref_put(&file->async_file->ref,
 939                          ib_uverbs_release_async_event_file);
 940
 941         kref_put(&file->ref, ib_uverbs_release_file);
 942         kobject_put(&dev->kobj);
 943
 944         return 0;
 945 }
 946
 947 static const struct file_operations uverbs_fops = {
 948         .owner   = THIS_MODULE,
 949         .write   = ib_uverbs_write,
 950         .open    = ib_uverbs_open,
 951         .release = ib_uverbs_close,
 952         .llseek  = no_llseek,
 953 };
 954
 955 static const struct file_operations uverbs_mmap_fops = {
 956         .owner   = THIS_MODULE,
 957         .write   = ib_uverbs_write,
 958         .mmap    = ib_uverbs_mmap,
 959         .open    = ib_uverbs_open,
 960         .release = ib_uverbs_close,
 961         .llseek  = no_llseek,
 962 };
 963
 964 static struct ib_client uverbs_client = {
 965         .name   = "uverbs",
 966         .add    = ib_uverbs_add_one,
 967         .remove = ib_uverbs_remove_one
 968 };
 969
 970 static ssize_t show_ibdev(struct device *device, struct device_attribute *attr,
 971                           char *buf)
 972 {
 973         int ret = -ENODEV;
 974         int srcu_key;
 975         struct ib_uverbs_device *dev = dev_get_drvdata(device);
 976         struct ib_device *ib_dev;
 977
 978         if (!dev)
 979                 return -ENODEV;
 980
 981         srcu_key = srcu_read_lock(&dev->disassociate_srcu);
 982         ib_dev = srcu_dereference(dev->ib_dev, &dev->disassociate_srcu);
 983         if (ib_dev)
 984                 ret = sprintf(buf, "%s\n", ib_dev->name);
 985         srcu_read_unlock(&dev->disassociate_srcu, srcu_key);
 986
 987         return ret;
 988 }
 989 static DEVICE_ATTR(ibdev, S_IRUGO, show_ibdev, NULL);
 990
 991 static ssize_t show_dev_abi_version(struct device *device,
 992                                     struct device_attribute *attr, char *buf)
 993 {
 994         struct ib_uverbs_device *dev = dev_get_drvdata(device);
 995         int ret = -ENODEV;
 996         int srcu_key;
 997         struct ib_device *ib_dev;
 998
 999         if (!dev)
1000                 return -ENODEV;
1001         srcu_key = srcu_read_lock(&dev->disassociate_srcu);
1002         ib_dev = srcu_dereference(dev->ib_dev, &dev->disassociate_srcu);
1003         if (ib_dev)
1004                 ret = sprintf(buf, "%d\n", ib_dev->uverbs_abi_ver);
1005         srcu_read_unlock(&dev->disassociate_srcu, srcu_key);
1006
1007         return ret;
1008 }
1009 static DEVICE_ATTR(abi_version, S_IRUGO, show_dev_abi_version, NULL);
1010
1011 static CLASS_ATTR_STRING(abi_version, S_IRUGO,
1012                          __stringify(IB_USER_VERBS_ABI_VERSION));
1013
1014 static dev_t overflow_maj;
1015 static DECLARE_BITMAP(overflow_map, IB_UVERBS_MAX_DEVICES);
1016
1017 /*
1018  * If we have more than IB_UVERBS_MAX_DEVICES, dynamically overflow by
1019  * requesting a new major number and doubling the number of max devices we
1020  * support. It's stupid, but simple.
1021  */
1022 static int find_overflow_devnum(void)
1023 {
1024         int ret;
1025
1026         if (!overflow_maj) {
1027                 ret = alloc_chrdev_region(&overflow_maj, 0, IB_UVERBS_MAX_DEVICES,
1028                                           "infiniband_verbs");
1029                 if (ret) {
1030                         pr_err("user_verbs: couldn't register dynamic device number\n");
1031                         return ret;
1032                 }
1033         }
1034
1035         ret = find_first_zero_bit(overflow_map, IB_UVERBS_MAX_DEVICES);
1036         if (ret >= IB_UVERBS_MAX_DEVICES)
1037                 return -1;
1038
1039         return ret;
1040 }
1041
1042 static void ib_uverbs_add_one(struct ib_device *device)
1043 {
1044         int devnum;
1045         dev_t base;
1046         struct ib_uverbs_device *uverbs_dev;
1047         int ret;
1048
1049         if (!device->alloc_ucontext)
1050                 return;
1051
1052         uverbs_dev = kzalloc(sizeof *uverbs_dev, GFP_KERNEL);
1053         if (!uverbs_dev)
1054                 return;
1055
1056         ret = init_srcu_struct(&uverbs_dev->disassociate_srcu);
1057         if (ret) {
1058                 kfree(uverbs_dev);
1059                 return;
1060         }
1061
1062         atomic_set(&uverbs_dev->refcount, 1);
1063         init_completion(&uverbs_dev->comp);
1064         uverbs_dev->xrcd_tree = RB_ROOT;
1065         mutex_init(&uverbs_dev->xrcd_tree_mutex);
1066         kobject_init(&uverbs_dev->kobj, &ib_uverbs_dev_ktype);
1067         mutex_init(&uverbs_dev->lists_mutex);
1068         INIT_LIST_HEAD(&uverbs_dev->uverbs_file_list);
1069         INIT_LIST_HEAD(&uverbs_dev->uverbs_events_file_list);
1070
1071         spin_lock(&map_lock);
1072         devnum = find_first_zero_bit(dev_map, IB_UVERBS_MAX_DEVICES);
1073         if (devnum >= IB_UVERBS_MAX_DEVICES) {
1074                 spin_unlock(&map_lock);
1075                 devnum = find_overflow_devnum();
1076                 if (devnum < 0)
1077                         goto err;
1078
1079                 spin_lock(&map_lock);
1080                 uverbs_dev->devnum = devnum + IB_UVERBS_MAX_DEVICES;
1081                 base = devnum + overflow_maj;
1082                 set_bit(devnum, overflow_map);
1083         } else {
1084                 uverbs_dev->devnum = devnum;
1085                 base = devnum + IB_UVERBS_BASE_DEV;
1086                 set_bit(devnum, dev_map);
1087         }
1088         spin_unlock(&map_lock);
1089
1090         rcu_assign_pointer(uverbs_dev->ib_dev, device);
1091         uverbs_dev->num_comp_vectors = device->num_comp_vectors;
1092
1093         cdev_init(&uverbs_dev->cdev, NULL);
1094         uverbs_dev->cdev.owner = THIS_MODULE;
1095         uverbs_dev->cdev.ops = device->mmap ? &uverbs_mmap_fops : &uverbs_fops;
1096         cdev_set_parent(&uverbs_dev->cdev, &uverbs_dev->kobj);
1097         kobject_set_name(&uverbs_dev->cdev.kobj, "uverbs%d", uverbs_dev->devnum);
1098         if (cdev_add(&uverbs_dev->cdev, base, 1))
1099                 goto err_cdev;
1100
1101         uverbs_dev->dev = device_create(uverbs_class, device->dev.parent,
1102                                         uverbs_dev->cdev.dev, uverbs_dev,
1103                                         "uverbs%d", uverbs_dev->devnum);
1104         if (IS_ERR(uverbs_dev->dev))
1105                 goto err_cdev;
1106
1107         if (device_create_file(uverbs_dev->dev, &dev_attr_ibdev))
1108                 goto err_class;
1109         if (device_create_file(uverbs_dev->dev, &dev_attr_abi_version))
1110                 goto err_class;
1111
1112         ib_set_client_data(device, &uverbs_client, uverbs_dev);
1113
1114         return;
1115
1116 err_class:
1117         device_destroy(uverbs_class, uverbs_dev->cdev.dev);
1118
1119 err_cdev:
1120         cdev_del(&uverbs_dev->cdev);
1121         if (uverbs_dev->devnum < IB_UVERBS_MAX_DEVICES)
1122                 clear_bit(devnum, dev_map);
1123         else
1124                 clear_bit(devnum, overflow_map);
1125
1126 err:
1127         if (atomic_dec_and_test(&uverbs_dev->refcount))
1128                 ib_uverbs_comp_dev(uverbs_dev);
1129         wait_for_completion(&uverbs_dev->comp);
1130         kobject_put(&uverbs_dev->kobj);
1131         return;
1132 }
1133
1134 static void ib_uverbs_free_hw_resources(struct ib_uverbs_device *uverbs_dev,
1135                                         struct ib_device *ib_dev)
1136 {
1137         struct ib_uverbs_file *file;
1138         struct ib_uverbs_async_event_file *event_file;
1139         struct ib_event event;
1140
1141         /* Pending running commands to terminate */
1142         synchronize_srcu(&uverbs_dev->disassociate_srcu);
1143         event.event = IB_EVENT_DEVICE_FATAL;
1144         event.element.port_num = 0;
1145         event.device = ib_dev;
1146
1147         mutex_lock(&uverbs_dev->lists_mutex);
1148         while (!list_empty(&uverbs_dev->uverbs_file_list)) {
1149                 struct ib_ucontext *ucontext;
1150                 file = list_first_entry(&uverbs_dev->uverbs_file_list,
1151                                         struct ib_uverbs_file, list);
1152                 file->is_closed = 1;
1153                 list_del(&file->list);
1154                 kref_get(&file->ref);
1155                 mutex_unlock(&uverbs_dev->lists_mutex);
1156
1157                 ib_uverbs_event_handler(&file->event_handler, &event);
1158
1159                 mutex_lock(&file->cleanup_mutex);
1160                 ucontext = file->ucontext;
1161                 file->ucontext = NULL;
1162                 mutex_unlock(&file->cleanup_mutex);
1163
1164                 /* At this point ib_uverbs_close cannot be running
1165                  * ib_uverbs_cleanup_ucontext
1166                  */
1167                 if (ucontext) {
1168                         /* We must release the mutex before going ahead and
1169                          * calling disassociate_ucontext. disassociate_ucontext
1170                          * might end up indirectly calling uverbs_close,
1171                          * for example due to freeing the resources
1172                          * (e.g mmput).
1173                          */
1174                         ib_dev->disassociate_ucontext(ucontext);
1175                         mutex_lock(&file->cleanup_mutex);
1176                         ib_uverbs_cleanup_ucontext(file, ucontext, true);
1177                         mutex_unlock(&file->cleanup_mutex);
1178                 }
1179
1180                 mutex_lock(&uverbs_dev->lists_mutex);
1181                 kref_put(&file->ref, ib_uverbs_release_file);
1182         }
1183
1184         while (!list_empty(&uverbs_dev->uverbs_events_file_list)) {
1185                 event_file = list_first_entry(&uverbs_dev->
1186                                               uverbs_events_file_list,
1187                                               struct ib_uverbs_async_event_file,
1188                                               list);
1189                 spin_lock_irq(&event_file->ev_queue.lock);
1190                 event_file->ev_queue.is_closed = 1;
1191                 spin_unlock_irq(&event_file->ev_queue.lock);
1192
1193                 list_del(&event_file->list);
1194                 ib_unregister_event_handler(
1195                         &event_file->uverbs_file->event_handler);
1196                 event_file->uverbs_file->event_handler.device =
1197                         NULL;
1198
1199                 wake_up_interruptible(&event_file->ev_queue.poll_wait);
1200                 kill_fasync(&event_file->ev_queue.async_queue, SIGIO, POLL_IN);
1201         }
1202         mutex_unlock(&uverbs_dev->lists_mutex);
1203 }
1204
1205 static void ib_uverbs_remove_one(struct ib_device *device, void *client_data)
1206 {
1207         struct ib_uverbs_device *uverbs_dev = client_data;
1208         int wait_clients = 1;
1209
1210         if (!uverbs_dev)
1211                 return;
1212
1213         dev_set_drvdata(uverbs_dev->dev, NULL);
1214         device_destroy(uverbs_class, uverbs_dev->cdev.dev);
1215         cdev_del(&uverbs_dev->cdev);
1216
1217         if (uverbs_dev->devnum < IB_UVERBS_MAX_DEVICES)
1218                 clear_bit(uverbs_dev->devnum, dev_map);
1219         else
1220                 clear_bit(uverbs_dev->devnum - IB_UVERBS_MAX_DEVICES, overflow_map);
1221
1222         if (device->disassociate_ucontext) {
1223                 /* We disassociate HW resources and immediately return.
1224                  * Userspace will see a EIO errno for all future access.
1225                  * Upon returning, ib_device may be freed internally and is not
1226                  * valid any more.
1227                  * uverbs_device is still available until all clients close
1228                  * their files, then the uverbs device ref count will be zero
1229                  * and its resources will be freed.
1230                  * Note: At this point no more files can be opened since the
1231                  * cdev was deleted, however active clients can still issue
1232                  * commands and close their open files.
1233                  */
1234                 rcu_assign_pointer(uverbs_dev->ib_dev, NULL);
1235                 ib_uverbs_free_hw_resources(uverbs_dev, device);
1236                 wait_clients = 0;
1237         }
1238
1239         if (atomic_dec_and_test(&uverbs_dev->refcount))
1240                 ib_uverbs_comp_dev(uverbs_dev);
1241         if (wait_clients)
1242                 wait_for_completion(&uverbs_dev->comp);
1243         kobject_put(&uverbs_dev->kobj);
1244 }
1245
1246 static char *uverbs_devnode(struct device *dev, umode_t *mode)
1247 {
1248         if (mode)
1249                 *mode = 0666;
1250         return kasprintf(GFP_KERNEL, "infiniband/%s", dev_name(dev));
1251 }
1252
1253 static int __init ib_uverbs_init(void)
1254 {
1255         int ret;
1256
1257         ret = register_chrdev_region(IB_UVERBS_BASE_DEV, IB_UVERBS_MAX_DEVICES,
1258                                      "infiniband_verbs");
1259         if (ret) {
1260                 pr_err("user_verbs: couldn't register device number\n");
1261                 goto out;
1262         }
1263
1264         uverbs_class = class_create(THIS_MODULE, "infiniband_verbs");
1265         if (IS_ERR(uverbs_class)) {
1266                 ret = PTR_ERR(uverbs_class);
1267                 pr_err("user_verbs: couldn't create class infiniband_verbs\n");
1268                 goto out_chrdev;
1269         }
1270
1271         uverbs_class->devnode = uverbs_devnode;
1272
1273         ret = class_create_file(uverbs_class, &class_attr_abi_version.attr);
1274         if (ret) {
1275                 pr_err("user_verbs: couldn't create abi_version attribute\n");
1276                 goto out_class;
1277         }
1278
1279         ret = ib_register_client(&uverbs_client);
1280         if (ret) {
1281                 pr_err("user_verbs: couldn't register client\n");
1282                 goto out_class;
1283         }
1284
1285         return 0;
1286
1287 out_class:
1288         class_destroy(uverbs_class);
1289
1290 out_chrdev:
1291         unregister_chrdev_region(IB_UVERBS_BASE_DEV, IB_UVERBS_MAX_DEVICES);
1292
1293 out:
1294         return ret;
1295 }
1296
1297 static void __exit ib_uverbs_cleanup(void)
1298 {
1299         ib_unregister_client(&uverbs_client);
1300         class_destroy(uverbs_class);
1301         unregister_chrdev_region(IB_UVERBS_BASE_DEV, IB_UVERBS_MAX_DEVICES);
1302         if (overflow_maj)
1303                 unregister_chrdev_region(overflow_maj, IB_UVERBS_MAX_DEVICES);
1304 }
1305
1306 module_init(ib_uverbs_init);
1307 module_exit(ib_uverbs_cleanup);