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 #include <rdma/uverbs_std_types.h>
  53
  54 #include "uverbs.h"
  55 #include "core_priv.h"
  56 #include "rdma_core.h"
  57
  58 MODULE_AUTHOR("Roland Dreier");
  59 MODULE_DESCRIPTION("InfiniBand userspace verbs access");
  60 MODULE_LICENSE("Dual BSD/GPL");
  61
  62 enum {
  63         IB_UVERBS_MAJOR       = 231,
  64         IB_UVERBS_BASE_MINOR  = 192,
  65         IB_UVERBS_MAX_DEVICES = RDMA_MAX_PORTS,
  66         IB_UVERBS_NUM_FIXED_MINOR = 32,
  67         IB_UVERBS_NUM_DYNAMIC_MINOR = IB_UVERBS_MAX_DEVICES - IB_UVERBS_NUM_FIXED_MINOR,
  68 };
  69
  70 #define IB_UVERBS_BASE_DEV      MKDEV(IB_UVERBS_MAJOR, IB_UVERBS_BASE_MINOR)
  71
  72 static dev_t dynamic_uverbs_dev;
  73 static struct class *uverbs_class;
  74
  75 static DECLARE_BITMAP(dev_map, IB_UVERBS_MAX_DEVICES);
  76
  77 static ssize_t (*uverbs_cmd_table[])(struct ib_uverbs_file *file,
  78                                      struct ib_device *ib_dev,
  79                                      const char __user *buf, int in_len,
  80                                      int out_len) = {
  81         [IB_USER_VERBS_CMD_GET_CONTEXT]         = ib_uverbs_get_context,
  82         [IB_USER_VERBS_CMD_QUERY_DEVICE]        = ib_uverbs_query_device,
  83         [IB_USER_VERBS_CMD_QUERY_PORT]          = ib_uverbs_query_port,
  84         [IB_USER_VERBS_CMD_ALLOC_PD]            = ib_uverbs_alloc_pd,
  85         [IB_USER_VERBS_CMD_DEALLOC_PD]          = ib_uverbs_dealloc_pd,
  86         [IB_USER_VERBS_CMD_REG_MR]              = ib_uverbs_reg_mr,
  87         [IB_USER_VERBS_CMD_REREG_MR]            = ib_uverbs_rereg_mr,
  88         [IB_USER_VERBS_CMD_DEREG_MR]            = ib_uverbs_dereg_mr,
  89         [IB_USER_VERBS_CMD_ALLOC_MW]            = ib_uverbs_alloc_mw,
  90         [IB_USER_VERBS_CMD_DEALLOC_MW]          = ib_uverbs_dealloc_mw,
  91         [IB_USER_VERBS_CMD_CREATE_COMP_CHANNEL] = ib_uverbs_create_comp_channel,
  92         [IB_USER_VERBS_CMD_CREATE_CQ]           = ib_uverbs_create_cq,
  93         [IB_USER_VERBS_CMD_RESIZE_CQ]           = ib_uverbs_resize_cq,
  94         [IB_USER_VERBS_CMD_POLL_CQ]             = ib_uverbs_poll_cq,
  95         [IB_USER_VERBS_CMD_REQ_NOTIFY_CQ]       = ib_uverbs_req_notify_cq,
  96         [IB_USER_VERBS_CMD_DESTROY_CQ]          = ib_uverbs_destroy_cq,
  97         [IB_USER_VERBS_CMD_CREATE_QP]           = ib_uverbs_create_qp,
  98         [IB_USER_VERBS_CMD_QUERY_QP]            = ib_uverbs_query_qp,
  99         [IB_USER_VERBS_CMD_MODIFY_QP]           = ib_uverbs_modify_qp,
 100         [IB_USER_VERBS_CMD_DESTROY_QP]          = ib_uverbs_destroy_qp,
 101         [IB_USER_VERBS_CMD_POST_SEND]           = ib_uverbs_post_send,
 102         [IB_USER_VERBS_CMD_POST_RECV]           = ib_uverbs_post_recv,
 103         [IB_USER_VERBS_CMD_POST_SRQ_RECV]       = ib_uverbs_post_srq_recv,
 104         [IB_USER_VERBS_CMD_CREATE_AH]           = ib_uverbs_create_ah,
 105         [IB_USER_VERBS_CMD_DESTROY_AH]          = ib_uverbs_destroy_ah,
 106         [IB_USER_VERBS_CMD_ATTACH_MCAST]        = ib_uverbs_attach_mcast,
 107         [IB_USER_VERBS_CMD_DETACH_MCAST]        = ib_uverbs_detach_mcast,
 108         [IB_USER_VERBS_CMD_CREATE_SRQ]          = ib_uverbs_create_srq,
 109         [IB_USER_VERBS_CMD_MODIFY_SRQ]          = ib_uverbs_modify_srq,
 110         [IB_USER_VERBS_CMD_QUERY_SRQ]           = ib_uverbs_query_srq,
 111         [IB_USER_VERBS_CMD_DESTROY_SRQ]         = ib_uverbs_destroy_srq,
 112         [IB_USER_VERBS_CMD_OPEN_XRCD]           = ib_uverbs_open_xrcd,
 113         [IB_USER_VERBS_CMD_CLOSE_XRCD]          = ib_uverbs_close_xrcd,
 114         [IB_USER_VERBS_CMD_CREATE_XSRQ]         = ib_uverbs_create_xsrq,
 115         [IB_USER_VERBS_CMD_OPEN_QP]             = ib_uverbs_open_qp,
 116 };
 117
 118 static int (*uverbs_ex_cmd_table[])(struct ib_uverbs_file *file,
 119                                     struct ib_device *ib_dev,
 120                                     struct ib_udata *ucore,
 121                                     struct ib_udata *uhw) = {
 122         [IB_USER_VERBS_EX_CMD_CREATE_FLOW]      = ib_uverbs_ex_create_flow,
 123         [IB_USER_VERBS_EX_CMD_DESTROY_FLOW]     = ib_uverbs_ex_destroy_flow,
 124         [IB_USER_VERBS_EX_CMD_QUERY_DEVICE]     = ib_uverbs_ex_query_device,
 125         [IB_USER_VERBS_EX_CMD_CREATE_CQ]        = ib_uverbs_ex_create_cq,
 126         [IB_USER_VERBS_EX_CMD_CREATE_QP]        = ib_uverbs_ex_create_qp,
 127         [IB_USER_VERBS_EX_CMD_CREATE_WQ]        = ib_uverbs_ex_create_wq,
 128         [IB_USER_VERBS_EX_CMD_MODIFY_WQ]        = ib_uverbs_ex_modify_wq,
 129         [IB_USER_VERBS_EX_CMD_DESTROY_WQ]       = ib_uverbs_ex_destroy_wq,
 130         [IB_USER_VERBS_EX_CMD_CREATE_RWQ_IND_TBL] = ib_uverbs_ex_create_rwq_ind_table,
 131         [IB_USER_VERBS_EX_CMD_DESTROY_RWQ_IND_TBL] = ib_uverbs_ex_destroy_rwq_ind_table,
 132         [IB_USER_VERBS_EX_CMD_MODIFY_QP]        = ib_uverbs_ex_modify_qp,
 133         [IB_USER_VERBS_EX_CMD_MODIFY_CQ]        = ib_uverbs_ex_modify_cq,
 134 };
 135
 136 static void ib_uverbs_add_one(struct ib_device *device);
 137 static void ib_uverbs_remove_one(struct ib_device *device, void *client_data);
 138
 139 int uverbs_dealloc_mw(struct ib_mw *mw)
 140 {
 141         struct ib_pd *pd = mw->pd;
 142         int ret;
 143
 144         ret = mw->device->dealloc_mw(mw);
 145         if (!ret)
 146                 atomic_dec(&pd->usecnt);
 147         return ret;
 148 }
 149
 150 static void ib_uverbs_release_dev(struct kobject *kobj)
 151 {
 152         struct ib_uverbs_device *dev =
 153                 container_of(kobj, struct ib_uverbs_device, kobj);
 154
 155         cleanup_srcu_struct(&dev->disassociate_srcu);
 156         kfree(dev);
 157 }
 158
 159 static struct kobj_type ib_uverbs_dev_ktype = {
 160         .release = ib_uverbs_release_dev,
 161 };
 162
 163 static void ib_uverbs_release_async_event_file(struct kref *ref)
 164 {
 165         struct ib_uverbs_async_event_file *file =
 166                 container_of(ref, struct ib_uverbs_async_event_file, ref);
 167
 168         kfree(file);
 169 }
 170
 171 void ib_uverbs_release_ucq(struct ib_uverbs_file *file,
 172                           struct ib_uverbs_completion_event_file *ev_file,
 173                           struct ib_ucq_object *uobj)
 174 {
 175         struct ib_uverbs_event *evt, *tmp;
 176
 177         if (ev_file) {
 178                 spin_lock_irq(&ev_file->ev_queue.lock);
 179                 list_for_each_entry_safe(evt, tmp, &uobj->comp_list, obj_list) {
 180                         list_del(&evt->list);
 181                         kfree(evt);
 182                 }
 183                 spin_unlock_irq(&ev_file->ev_queue.lock);
 184
 185                 uverbs_uobject_put(&ev_file->uobj_file.uobj);
 186         }
 187
 188         spin_lock_irq(&file->async_file->ev_queue.lock);
 189         list_for_each_entry_safe(evt, tmp, &uobj->async_list, obj_list) {
 190                 list_del(&evt->list);
 191                 kfree(evt);
 192         }
 193         spin_unlock_irq(&file->async_file->ev_queue.lock);
 194 }
 195
 196 void ib_uverbs_release_uevent(struct ib_uverbs_file *file,
 197                               struct ib_uevent_object *uobj)
 198 {
 199         struct ib_uverbs_event *evt, *tmp;
 200
 201         spin_lock_irq(&file->async_file->ev_queue.lock);
 202         list_for_each_entry_safe(evt, tmp, &uobj->event_list, obj_list) {
 203                 list_del(&evt->list);
 204                 kfree(evt);
 205         }
 206         spin_unlock_irq(&file->async_file->ev_queue.lock);
 207 }
 208
 209 void ib_uverbs_detach_umcast(struct ib_qp *qp,
 210                              struct ib_uqp_object *uobj)
 211 {
 212         struct ib_uverbs_mcast_entry *mcast, *tmp;
 213
 214         list_for_each_entry_safe(mcast, tmp, &uobj->mcast_list, list) {
 215                 ib_detach_mcast(qp, &mcast->gid, mcast->lid);
 216                 list_del(&mcast->list);
 217                 kfree(mcast);
 218         }
 219 }
 220
 221 static int ib_uverbs_cleanup_ucontext(struct ib_uverbs_file *file,
 222                                       struct ib_ucontext *context,
 223                                       bool device_removed)
 224 {
 225         context->closing = 1;
 226         uverbs_cleanup_ucontext(context, device_removed);
 227         put_pid(context->tgid);
 228
 229         ib_rdmacg_uncharge(&context->cg_obj, context->device,
 230                            RDMACG_RESOURCE_HCA_HANDLE);
 231
 232         return context->device->dealloc_ucontext(context);
 233 }
 234
 235 static void ib_uverbs_comp_dev(struct ib_uverbs_device *dev)
 236 {
 237         complete(&dev->comp);
 238 }
 239
 240 void ib_uverbs_release_file(struct kref *ref)
 241 {
 242         struct ib_uverbs_file *file =
 243                 container_of(ref, struct ib_uverbs_file, ref);
 244         struct ib_device *ib_dev;
 245         int srcu_key;
 246
 247         srcu_key = srcu_read_lock(&file->device->disassociate_srcu);
 248         ib_dev = srcu_dereference(file->device->ib_dev,
 249                                   &file->device->disassociate_srcu);
 250         if (ib_dev && !ib_dev->disassociate_ucontext)
 251                 module_put(ib_dev->owner);
 252         srcu_read_unlock(&file->device->disassociate_srcu, srcu_key);
 253
 254         if (atomic_dec_and_test(&file->device->refcount))
 255                 ib_uverbs_comp_dev(file->device);
 256
 257         kobject_put(&file->device->kobj);
 258         kfree(file);
 259 }
 260
 261 static ssize_t ib_uverbs_event_read(struct ib_uverbs_event_queue *ev_queue,
 262                                     struct ib_uverbs_file *uverbs_file,
 263                                     struct file *filp, char __user *buf,
 264                                     size_t count, loff_t *pos,
 265                                     size_t eventsz)
 266 {
 267         struct ib_uverbs_event *event;
 268         int ret = 0;
 269
 270         spin_lock_irq(&ev_queue->lock);
 271
 272         while (list_empty(&ev_queue->event_list)) {
 273                 spin_unlock_irq(&ev_queue->lock);
 274
 275                 if (filp->f_flags & O_NONBLOCK)
 276                         return -EAGAIN;
 277
 278                 if (wait_event_interruptible(ev_queue->poll_wait,
 279                                              (!list_empty(&ev_queue->event_list) ||
 280                         /* The barriers built into wait_event_interruptible()
 281                          * and wake_up() guarentee this will see the null set
 282                          * without using RCU
 283                          */
 284                                              !uverbs_file->device->ib_dev)))
 285                         return -ERESTARTSYS;
 286
 287                 /* If device was disassociated and no event exists set an error */
 288                 if (list_empty(&ev_queue->event_list) &&
 289                     !uverbs_file->device->ib_dev)
 290                         return -EIO;
 291
 292                 spin_lock_irq(&ev_queue->lock);
 293         }
 294
 295         event = list_entry(ev_queue->event_list.next, struct ib_uverbs_event, list);
 296
 297         if (eventsz > count) {
 298                 ret   = -EINVAL;
 299                 event = NULL;
 300         } else {
 301                 list_del(ev_queue->event_list.next);
 302                 if (event->counter) {
 303                         ++(*event->counter);
 304                         list_del(&event->obj_list);
 305                 }
 306         }
 307
 308         spin_unlock_irq(&ev_queue->lock);
 309
 310         if (event) {
 311                 if (copy_to_user(buf, event, eventsz))
 312                         ret = -EFAULT;
 313                 else
 314                         ret = eventsz;
 315         }
 316
 317         kfree(event);
 318
 319         return ret;
 320 }
 321
 322 static ssize_t ib_uverbs_async_event_read(struct file *filp, char __user *buf,
 323                                           size_t count, loff_t *pos)
 324 {
 325         struct ib_uverbs_async_event_file *file = filp->private_data;
 326
 327         return ib_uverbs_event_read(&file->ev_queue, file->uverbs_file, filp,
 328                                     buf, count, pos,
 329                                     sizeof(struct ib_uverbs_async_event_desc));
 330 }
 331
 332 static ssize_t ib_uverbs_comp_event_read(struct file *filp, char __user *buf,
 333                                          size_t count, loff_t *pos)
 334 {
 335         struct ib_uverbs_completion_event_file *comp_ev_file =
 336                 filp->private_data;
 337
 338         return ib_uverbs_event_read(&comp_ev_file->ev_queue,
 339                                     comp_ev_file->uobj_file.ufile, filp,
 340                                     buf, count, pos,
 341                                     sizeof(struct ib_uverbs_comp_event_desc));
 342 }
 343
 344 static __poll_t ib_uverbs_event_poll(struct ib_uverbs_event_queue *ev_queue,
 345                                          struct file *filp,
 346                                          struct poll_table_struct *wait)
 347 {
 348         __poll_t pollflags = 0;
 349
 350         poll_wait(filp, &ev_queue->poll_wait, wait);
 351
 352         spin_lock_irq(&ev_queue->lock);
 353         if (!list_empty(&ev_queue->event_list))
 354                 pollflags = EPOLLIN | EPOLLRDNORM;
 355         spin_unlock_irq(&ev_queue->lock);
 356
 357         return pollflags;
 358 }
 359
 360 static __poll_t ib_uverbs_async_event_poll(struct file *filp,
 361                                                struct poll_table_struct *wait)
 362 {
 363         return ib_uverbs_event_poll(filp->private_data, filp, wait);
 364 }
 365
 366 static __poll_t ib_uverbs_comp_event_poll(struct file *filp,
 367                                               struct poll_table_struct *wait)
 368 {
 369         struct ib_uverbs_completion_event_file *comp_ev_file =
 370                 filp->private_data;
 371
 372         return ib_uverbs_event_poll(&comp_ev_file->ev_queue, filp, wait);
 373 }
 374
 375 static int ib_uverbs_async_event_fasync(int fd, struct file *filp, int on)
 376 {
 377         struct ib_uverbs_event_queue *ev_queue = filp->private_data;
 378
 379         return fasync_helper(fd, filp, on, &ev_queue->async_queue);
 380 }
 381
 382 static int ib_uverbs_comp_event_fasync(int fd, struct file *filp, int on)
 383 {
 384         struct ib_uverbs_completion_event_file *comp_ev_file =
 385                 filp->private_data;
 386
 387         return fasync_helper(fd, filp, on, &comp_ev_file->ev_queue.async_queue);
 388 }
 389
 390 static int ib_uverbs_async_event_close(struct inode *inode, struct file *filp)
 391 {
 392         struct ib_uverbs_async_event_file *file = filp->private_data;
 393         struct ib_uverbs_file *uverbs_file = file->uverbs_file;
 394         struct ib_uverbs_event *entry, *tmp;
 395         int closed_already = 0;
 396
 397         mutex_lock(&uverbs_file->device->lists_mutex);
 398         spin_lock_irq(&file->ev_queue.lock);
 399         closed_already = file->ev_queue.is_closed;
 400         file->ev_queue.is_closed = 1;
 401         list_for_each_entry_safe(entry, tmp, &file->ev_queue.event_list, list) {
 402                 if (entry->counter)
 403                         list_del(&entry->obj_list);
 404                 kfree(entry);
 405         }
 406         spin_unlock_irq(&file->ev_queue.lock);
 407         if (!closed_already) {
 408                 list_del(&file->list);
 409                 ib_unregister_event_handler(&uverbs_file->event_handler);
 410         }
 411         mutex_unlock(&uverbs_file->device->lists_mutex);
 412
 413         kref_put(&uverbs_file->ref, ib_uverbs_release_file);
 414         kref_put(&file->ref, ib_uverbs_release_async_event_file);
 415
 416         return 0;
 417 }
 418
 419 static int ib_uverbs_comp_event_close(struct inode *inode, struct file *filp)
 420 {
 421         struct ib_uverbs_completion_event_file *file = filp->private_data;
 422         struct ib_uverbs_event *entry, *tmp;
 423
 424         spin_lock_irq(&file->ev_queue.lock);
 425         list_for_each_entry_safe(entry, tmp, &file->ev_queue.event_list, list) {
 426                 if (entry->counter)
 427                         list_del(&entry->obj_list);
 428                 kfree(entry);
 429         }
 430         spin_unlock_irq(&file->ev_queue.lock);
 431
 432         uverbs_close_fd(filp);
 433
 434         return 0;
 435 }
 436
 437 const struct file_operations uverbs_event_fops = {
 438         .owner   = THIS_MODULE,
 439         .read    = ib_uverbs_comp_event_read,
 440         .poll    = ib_uverbs_comp_event_poll,
 441         .release = ib_uverbs_comp_event_close,
 442         .fasync  = ib_uverbs_comp_event_fasync,
 443         .llseek  = no_llseek,
 444 };
 445
 446 static const struct file_operations uverbs_async_event_fops = {
 447         .owner   = THIS_MODULE,
 448         .read    = ib_uverbs_async_event_read,
 449         .poll    = ib_uverbs_async_event_poll,
 450         .release = ib_uverbs_async_event_close,
 451         .fasync  = ib_uverbs_async_event_fasync,
 452         .llseek  = no_llseek,
 453 };
 454
 455 void ib_uverbs_comp_handler(struct ib_cq *cq, void *cq_context)
 456 {
 457         struct ib_uverbs_event_queue   *ev_queue = cq_context;
 458         struct ib_ucq_object           *uobj;
 459         struct ib_uverbs_event         *entry;
 460         unsigned long                   flags;
 461
 462         if (!ev_queue)
 463                 return;
 464
 465         spin_lock_irqsave(&ev_queue->lock, flags);
 466         if (ev_queue->is_closed) {
 467                 spin_unlock_irqrestore(&ev_queue->lock, flags);
 468                 return;
 469         }
 470
 471         entry = kmalloc(sizeof *entry, GFP_ATOMIC);
 472         if (!entry) {
 473                 spin_unlock_irqrestore(&ev_queue->lock, flags);
 474                 return;
 475         }
 476
 477         uobj = container_of(cq->uobject, struct ib_ucq_object, uobject);
 478
 479         entry->desc.comp.cq_handle = cq->uobject->user_handle;
 480         entry->counter             = &uobj->comp_events_reported;
 481
 482         list_add_tail(&entry->list, &ev_queue->event_list);
 483         list_add_tail(&entry->obj_list, &uobj->comp_list);
 484         spin_unlock_irqrestore(&ev_queue->lock, flags);
 485
 486         wake_up_interruptible(&ev_queue->poll_wait);
 487         kill_fasync(&ev_queue->async_queue, SIGIO, POLL_IN);
 488 }
 489
 490 static void ib_uverbs_async_handler(struct ib_uverbs_file *file,
 491                                     __u64 element, __u64 event,
 492                                     struct list_head *obj_list,
 493                                     u32 *counter)
 494 {
 495         struct ib_uverbs_event *entry;
 496         unsigned long flags;
 497
 498         spin_lock_irqsave(&file->async_file->ev_queue.lock, flags);
 499         if (file->async_file->ev_queue.is_closed) {
 500                 spin_unlock_irqrestore(&file->async_file->ev_queue.lock, flags);
 501                 return;
 502         }
 503
 504         entry = kmalloc(sizeof *entry, GFP_ATOMIC);
 505         if (!entry) {
 506                 spin_unlock_irqrestore(&file->async_file->ev_queue.lock, flags);
 507                 return;
 508         }
 509
 510         entry->desc.async.element    = element;
 511         entry->desc.async.event_type = event;
 512         entry->desc.async.reserved   = 0;
 513         entry->counter               = counter;
 514
 515         list_add_tail(&entry->list, &file->async_file->ev_queue.event_list);
 516         if (obj_list)
 517                 list_add_tail(&entry->obj_list, obj_list);
 518         spin_unlock_irqrestore(&file->async_file->ev_queue.lock, flags);
 519
 520         wake_up_interruptible(&file->async_file->ev_queue.poll_wait);
 521         kill_fasync(&file->async_file->ev_queue.async_queue, SIGIO, POLL_IN);
 522 }
 523
 524 void ib_uverbs_cq_event_handler(struct ib_event *event, void *context_ptr)
 525 {
 526         struct ib_ucq_object *uobj = container_of(event->element.cq->uobject,
 527                                                   struct ib_ucq_object, uobject);
 528
 529         ib_uverbs_async_handler(uobj->uverbs_file, uobj->uobject.user_handle,
 530                                 event->event, &uobj->async_list,
 531                                 &uobj->async_events_reported);
 532 }
 533
 534 void ib_uverbs_qp_event_handler(struct ib_event *event, void *context_ptr)
 535 {
 536         struct ib_uevent_object *uobj;
 537
 538         /* for XRC target qp's, check that qp is live */
 539         if (!event->element.qp->uobject)
 540                 return;
 541
 542         uobj = container_of(event->element.qp->uobject,
 543                             struct ib_uevent_object, uobject);
 544
 545         ib_uverbs_async_handler(context_ptr, uobj->uobject.user_handle,
 546                                 event->event, &uobj->event_list,
 547                                 &uobj->events_reported);
 548 }
 549
 550 void ib_uverbs_wq_event_handler(struct ib_event *event, void *context_ptr)
 551 {
 552         struct ib_uevent_object *uobj = container_of(event->element.wq->uobject,
 553                                                   struct ib_uevent_object, uobject);
 554
 555         ib_uverbs_async_handler(context_ptr, uobj->uobject.user_handle,
 556                                 event->event, &uobj->event_list,
 557                                 &uobj->events_reported);
 558 }
 559
 560 void ib_uverbs_srq_event_handler(struct ib_event *event, void *context_ptr)
 561 {
 562         struct ib_uevent_object *uobj;
 563
 564         uobj = container_of(event->element.srq->uobject,
 565                             struct ib_uevent_object, uobject);
 566
 567         ib_uverbs_async_handler(context_ptr, uobj->uobject.user_handle,
 568                                 event->event, &uobj->event_list,
 569                                 &uobj->events_reported);
 570 }
 571
 572 void ib_uverbs_event_handler(struct ib_event_handler *handler,
 573                              struct ib_event *event)
 574 {
 575         struct ib_uverbs_file *file =
 576                 container_of(handler, struct ib_uverbs_file, event_handler);
 577
 578         ib_uverbs_async_handler(file, event->element.port_num, event->event,
 579                                 NULL, NULL);
 580 }
 581
 582 void ib_uverbs_free_async_event_file(struct ib_uverbs_file *file)
 583 {
 584         kref_put(&file->async_file->ref, ib_uverbs_release_async_event_file);
 585         file->async_file = NULL;
 586 }
 587
 588 void ib_uverbs_init_event_queue(struct ib_uverbs_event_queue *ev_queue)
 589 {
 590         spin_lock_init(&ev_queue->lock);
 591         INIT_LIST_HEAD(&ev_queue->event_list);
 592         init_waitqueue_head(&ev_queue->poll_wait);
 593         ev_queue->is_closed   = 0;
 594         ev_queue->async_queue = NULL;
 595 }
 596
 597 struct file *ib_uverbs_alloc_async_event_file(struct ib_uverbs_file *uverbs_file,
 598                                               struct ib_device  *ib_dev)
 599 {
 600         struct ib_uverbs_async_event_file *ev_file;
 601         struct file *filp;
 602
 603         ev_file = kzalloc(sizeof(*ev_file), GFP_KERNEL);
 604         if (!ev_file)
 605                 return ERR_PTR(-ENOMEM);
 606
 607         ib_uverbs_init_event_queue(&ev_file->ev_queue);
 608         ev_file->uverbs_file = uverbs_file;
 609         kref_get(&ev_file->uverbs_file->ref);
 610         kref_init(&ev_file->ref);
 611         filp = anon_inode_getfile("[infinibandevent]", &uverbs_async_event_fops,
 612                                   ev_file, O_RDONLY);
 613         if (IS_ERR(filp))
 614                 goto err_put_refs;
 615
 616         mutex_lock(&uverbs_file->device->lists_mutex);
 617         list_add_tail(&ev_file->list,
 618                       &uverbs_file->device->uverbs_events_file_list);
 619         mutex_unlock(&uverbs_file->device->lists_mutex);
 620
 621         WARN_ON(uverbs_file->async_file);
 622         uverbs_file->async_file = ev_file;
 623         kref_get(&uverbs_file->async_file->ref);
 624         INIT_IB_EVENT_HANDLER(&uverbs_file->event_handler,
 625                               ib_dev,
 626                               ib_uverbs_event_handler);
 627         ib_register_event_handler(&uverbs_file->event_handler);
 628         /* At that point async file stuff was fully set */
 629
 630         return filp;
 631
 632 err_put_refs:
 633         kref_put(&ev_file->uverbs_file->ref, ib_uverbs_release_file);
 634         kref_put(&ev_file->ref, ib_uverbs_release_async_event_file);
 635         return filp;
 636 }
 637
 638 static int verify_command_mask(struct ib_device *ib_dev, __u32 command)
 639 {
 640         u64 mask;
 641
 642         if (command <= IB_USER_VERBS_CMD_OPEN_QP)
 643                 mask = ib_dev->uverbs_cmd_mask;
 644         else
 645                 mask = ib_dev->uverbs_ex_cmd_mask;
 646
 647         if (mask & ((u64)1 << command))
 648                 return 0;
 649
 650         return -1;
 651 }
 652
 653 static bool verify_command_idx(u32 command, bool extended)
 654 {
 655         if (extended)
 656                 return command < ARRAY_SIZE(uverbs_ex_cmd_table);
 657
 658         return command < ARRAY_SIZE(uverbs_cmd_table);
 659 }
 660
 661 static ssize_t ib_uverbs_write(struct file *filp, const char __user *buf,
 662                              size_t count, loff_t *pos)
 663 {
 664         struct ib_uverbs_file *file = filp->private_data;
 665         struct ib_device *ib_dev;
 666         struct ib_uverbs_cmd_hdr hdr;
 667         bool extended_command;
 668         __u32 command;
 669         __u32 flags;
 670         int srcu_key;
 671         ssize_t ret;
 672
 673         if (!ib_safe_file_access(filp)) {
 674                 pr_err_once("uverbs_write: process %d (%s) changed security contexts after opening file descriptor, this is not allowed.\n",
 675                             task_tgid_vnr(current), current->comm);
 676                 return -EACCES;
 677         }
 678
 679         if (count < sizeof hdr)
 680                 return -EINVAL;
 681
 682         if (copy_from_user(&hdr, buf, sizeof hdr))
 683                 return -EFAULT;
 684
 685         srcu_key = srcu_read_lock(&file->device->disassociate_srcu);
 686         ib_dev = srcu_dereference(file->device->ib_dev,
 687                                   &file->device->disassociate_srcu);
 688         if (!ib_dev) {
 689                 ret = -EIO;
 690                 goto out;
 691         }
 692
 693         if (hdr.command & ~(__u32)(IB_USER_VERBS_CMD_FLAGS_MASK |
 694                                    IB_USER_VERBS_CMD_COMMAND_MASK)) {
 695                 ret = -EINVAL;
 696                 goto out;
 697         }
 698
 699         command = hdr.command & IB_USER_VERBS_CMD_COMMAND_MASK;
 700         flags = (hdr.command &
 701                  IB_USER_VERBS_CMD_FLAGS_MASK) >> IB_USER_VERBS_CMD_FLAGS_SHIFT;
 702
 703         extended_command = flags & IB_USER_VERBS_CMD_FLAG_EXTENDED;
 704         if (!verify_command_idx(command, extended_command)) {
 705                 ret = -EINVAL;
 706                 goto out;
 707         }
 708
 709         if (verify_command_mask(ib_dev, command)) {
 710                 ret = -EOPNOTSUPP;
 711                 goto out;
 712         }
 713
 714         if (!file->ucontext &&
 715             command != IB_USER_VERBS_CMD_GET_CONTEXT) {
 716                 ret = -EINVAL;
 717                 goto out;
 718         }
 719
 720         if (!flags) {
 721                 if (!uverbs_cmd_table[command]) {
 722                         ret = -EINVAL;
 723                         goto out;
 724                 }
 725
 726                 if (hdr.in_words * 4 != count) {
 727                         ret = -EINVAL;
 728                         goto out;
 729                 }
 730
 731                 ret = uverbs_cmd_table[command](file, ib_dev,
 732                                                  buf + sizeof(hdr),
 733                                                  hdr.in_words * 4,
 734                                                  hdr.out_words * 4);
 735
 736         } else if (flags == IB_USER_VERBS_CMD_FLAG_EXTENDED) {
 737                 struct ib_uverbs_ex_cmd_hdr ex_hdr;
 738                 struct ib_udata ucore;
 739                 struct ib_udata uhw;
 740                 size_t written_count = count;
 741
 742                 if (!uverbs_ex_cmd_table[command]) {
 743                         ret = -ENOSYS;
 744                         goto out;
 745                 }
 746
 747                 if (!file->ucontext) {
 748                         ret = -EINVAL;
 749                         goto out;
 750                 }
 751
 752                 if (count < (sizeof(hdr) + sizeof(ex_hdr))) {
 753                         ret = -EINVAL;
 754                         goto out;
 755                 }
 756
 757                 if (copy_from_user(&ex_hdr, buf + sizeof(hdr), sizeof(ex_hdr))) {
 758                         ret = -EFAULT;
 759                         goto out;
 760                 }
 761
 762                 count -= sizeof(hdr) + sizeof(ex_hdr);
 763                 buf += sizeof(hdr) + sizeof(ex_hdr);
 764
 765                 if ((hdr.in_words + ex_hdr.provider_in_words) * 8 != count) {
 766                         ret = -EINVAL;
 767                         goto out;
 768                 }
 769
 770                 if (ex_hdr.cmd_hdr_reserved) {
 771                         ret = -EINVAL;
 772                         goto out;
 773                 }
 774
 775                 if (ex_hdr.response) {
 776                         if (!hdr.out_words && !ex_hdr.provider_out_words) {
 777                                 ret = -EINVAL;
 778                                 goto out;
 779                         }
 780
 781                         if (!access_ok(VERIFY_WRITE,
 782                                        u64_to_user_ptr(ex_hdr.response),
 783                                        (hdr.out_words + ex_hdr.provider_out_words) * 8)) {
 784                                 ret = -EFAULT;
 785                                 goto out;
 786                         }
 787                 } else {
 788                         if (hdr.out_words || ex_hdr.provider_out_words) {
 789                                 ret = -EINVAL;
 790                                 goto out;
 791                         }
 792                 }
 793
 794                 ib_uverbs_init_udata_buf_or_null(&ucore, buf,
 795                                         u64_to_user_ptr(ex_hdr.response),
 796                                         hdr.in_words * 8, hdr.out_words * 8);
 797
 798                 ib_uverbs_init_udata_buf_or_null(&uhw,
 799                                         buf + ucore.inlen,
 800                                         u64_to_user_ptr(ex_hdr.response) + ucore.outlen,
 801                                         ex_hdr.provider_in_words * 8,
 802                                         ex_hdr.provider_out_words * 8);
 803
 804                 ret = uverbs_ex_cmd_table[command](file, ib_dev, &ucore, &uhw);
 805                 if (!ret)
 806                         ret = written_count;
 807         } else {
 808                 ret = -ENOSYS;
 809         }
 810
 811 out:
 812         srcu_read_unlock(&file->device->disassociate_srcu, srcu_key);
 813         return ret;
 814 }
 815
 816 static int ib_uverbs_mmap(struct file *filp, struct vm_area_struct *vma)
 817 {
 818         struct ib_uverbs_file *file = filp->private_data;
 819         struct ib_device *ib_dev;
 820         int ret = 0;
 821         int srcu_key;
 822
 823         srcu_key = srcu_read_lock(&file->device->disassociate_srcu);
 824         ib_dev = srcu_dereference(file->device->ib_dev,
 825                                   &file->device->disassociate_srcu);
 826         if (!ib_dev) {
 827                 ret = -EIO;
 828                 goto out;
 829         }
 830
 831         if (!file->ucontext)
 832                 ret = -ENODEV;
 833         else
 834                 ret = ib_dev->mmap(file->ucontext, vma);
 835 out:
 836         srcu_read_unlock(&file->device->disassociate_srcu, srcu_key);
 837         return ret;
 838 }
 839
 840 /*
 841  * ib_uverbs_open() does not need the BKL:
 842  *
 843  *  - the ib_uverbs_device structures are properly reference counted and
 844  *    everything else is purely local to the file being created, so
 845  *    races against other open calls are not a problem;
 846  *  - there is no ioctl method to race against;
 847  *  - the open method will either immediately run -ENXIO, or all
 848  *    required initialization will be done.
 849  */
 850 static int ib_uverbs_open(struct inode *inode, struct file *filp)
 851 {
 852         struct ib_uverbs_device *dev;
 853         struct ib_uverbs_file *file;
 854         struct ib_device *ib_dev;
 855         int ret;
 856         int module_dependent;
 857         int srcu_key;
 858
 859         dev = container_of(inode->i_cdev, struct ib_uverbs_device, cdev);
 860         if (!atomic_inc_not_zero(&dev->refcount))
 861                 return -ENXIO;
 862
 863         srcu_key = srcu_read_lock(&dev->disassociate_srcu);
 864         mutex_lock(&dev->lists_mutex);
 865         ib_dev = srcu_dereference(dev->ib_dev,
 866                                   &dev->disassociate_srcu);
 867         if (!ib_dev) {
 868                 ret = -EIO;
 869                 goto err;
 870         }
 871
 872         /* In case IB device supports disassociate ucontext, there is no hard
 873          * dependency between uverbs device and its low level device.
 874          */
 875         module_dependent = !(ib_dev->disassociate_ucontext);
 876
 877         if (module_dependent) {
 878                 if (!try_module_get(ib_dev->owner)) {
 879                         ret = -ENODEV;
 880                         goto err;
 881                 }
 882         }
 883
 884         file = kzalloc(sizeof(*file), GFP_KERNEL);
 885         if (!file) {
 886                 ret = -ENOMEM;
 887                 if (module_dependent)
 888                         goto err_module;
 889
 890                 goto err;
 891         }
 892
 893         file->device     = dev;
 894         spin_lock_init(&file->idr_lock);
 895         idr_init(&file->idr);
 896         file->ucontext   = NULL;
 897         file->async_file = NULL;
 898         kref_init(&file->ref);
 899         mutex_init(&file->mutex);
 900         mutex_init(&file->cleanup_mutex);
 901
 902         filp->private_data = file;
 903         kobject_get(&dev->kobj);
 904         list_add_tail(&file->list, &dev->uverbs_file_list);
 905         mutex_unlock(&dev->lists_mutex);
 906         srcu_read_unlock(&dev->disassociate_srcu, srcu_key);
 907
 908         return nonseekable_open(inode, filp);
 909
 910 err_module:
 911         module_put(ib_dev->owner);
 912
 913 err:
 914         mutex_unlock(&dev->lists_mutex);
 915         srcu_read_unlock(&dev->disassociate_srcu, srcu_key);
 916         if (atomic_dec_and_test(&dev->refcount))
 917                 ib_uverbs_comp_dev(dev);
 918
 919         return ret;
 920 }
 921
 922 static int ib_uverbs_close(struct inode *inode, struct file *filp)
 923 {
 924         struct ib_uverbs_file *file = filp->private_data;
 925
 926         mutex_lock(&file->cleanup_mutex);
 927         if (file->ucontext) {
 928                 ib_uverbs_cleanup_ucontext(file, file->ucontext, false);
 929                 file->ucontext = NULL;
 930         }
 931         mutex_unlock(&file->cleanup_mutex);
 932         idr_destroy(&file->idr);
 933
 934         mutex_lock(&file->device->lists_mutex);
 935         if (!file->is_closed) {
 936                 list_del(&file->list);
 937                 file->is_closed = 1;
 938         }
 939         mutex_unlock(&file->device->lists_mutex);
 940
 941         if (file->async_file)
 942                 kref_put(&file->async_file->ref,
 943                          ib_uverbs_release_async_event_file);
 944
 945         kref_put(&file->ref, ib_uverbs_release_file);
 946
 947         return 0;
 948 }
 949
 950 static const struct file_operations uverbs_fops = {
 951         .owner   = THIS_MODULE,
 952         .write   = ib_uverbs_write,
 953         .open    = ib_uverbs_open,
 954         .release = ib_uverbs_close,
 955         .llseek  = no_llseek,
 956 #if IS_ENABLED(CONFIG_INFINIBAND_EXP_USER_ACCESS)
 957         .unlocked_ioctl = ib_uverbs_ioctl,
 958         .compat_ioctl = ib_uverbs_ioctl,
 959 #endif
 960 };
 961
 962 static const struct file_operations uverbs_mmap_fops = {
 963         .owner   = THIS_MODULE,
 964         .write   = ib_uverbs_write,
 965         .mmap    = ib_uverbs_mmap,
 966         .open    = ib_uverbs_open,
 967         .release = ib_uverbs_close,
 968         .llseek  = no_llseek,
 969 #if IS_ENABLED(CONFIG_INFINIBAND_EXP_USER_ACCESS)
 970         .unlocked_ioctl = ib_uverbs_ioctl,
 971         .compat_ioctl = ib_uverbs_ioctl,
 972 #endif
 973 };
 974
 975 static struct ib_client uverbs_client = {
 976         .name   = "uverbs",
 977         .add    = ib_uverbs_add_one,
 978         .remove = ib_uverbs_remove_one
 979 };
 980
 981 static ssize_t show_ibdev(struct device *device, struct device_attribute *attr,
 982                           char *buf)
 983 {
 984         int ret = -ENODEV;
 985         int srcu_key;
 986         struct ib_uverbs_device *dev = dev_get_drvdata(device);
 987         struct ib_device *ib_dev;
 988
 989         if (!dev)
 990                 return -ENODEV;
 991
 992         srcu_key = srcu_read_lock(&dev->disassociate_srcu);
 993         ib_dev = srcu_dereference(dev->ib_dev, &dev->disassociate_srcu);
 994         if (ib_dev)
 995                 ret = sprintf(buf, "%s\n", ib_dev->name);
 996         srcu_read_unlock(&dev->disassociate_srcu, srcu_key);
 997
 998         return ret;
 999 }
1000 static DEVICE_ATTR(ibdev, S_IRUGO, show_ibdev, NULL);
1001
1002 static ssize_t show_dev_abi_version(struct device *device,
1003                                     struct device_attribute *attr, char *buf)
1004 {
1005         struct ib_uverbs_device *dev = dev_get_drvdata(device);
1006         int ret = -ENODEV;
1007         int srcu_key;
1008         struct ib_device *ib_dev;
1009
1010         if (!dev)
1011                 return -ENODEV;
1012         srcu_key = srcu_read_lock(&dev->disassociate_srcu);
1013         ib_dev = srcu_dereference(dev->ib_dev, &dev->disassociate_srcu);
1014         if (ib_dev)
1015                 ret = sprintf(buf, "%d\n", ib_dev->uverbs_abi_ver);
1016         srcu_read_unlock(&dev->disassociate_srcu, srcu_key);
1017
1018         return ret;
1019 }
1020 static DEVICE_ATTR(abi_version, S_IRUGO, show_dev_abi_version, NULL);
1021
1022 static CLASS_ATTR_STRING(abi_version, S_IRUGO,
1023                          __stringify(IB_USER_VERBS_ABI_VERSION));
1024
1025 static void ib_uverbs_add_one(struct ib_device *device)
1026 {
1027         int devnum;
1028         dev_t base;
1029         struct ib_uverbs_device *uverbs_dev;
1030         int ret;
1031
1032         if (!device->alloc_ucontext)
1033                 return;
1034
1035         uverbs_dev = kzalloc(sizeof *uverbs_dev, GFP_KERNEL);
1036         if (!uverbs_dev)
1037                 return;
1038
1039         ret = init_srcu_struct(&uverbs_dev->disassociate_srcu);
1040         if (ret) {
1041                 kfree(uverbs_dev);
1042                 return;
1043         }
1044
1045         atomic_set(&uverbs_dev->refcount, 1);
1046         init_completion(&uverbs_dev->comp);
1047         uverbs_dev->xrcd_tree = RB_ROOT;
1048         mutex_init(&uverbs_dev->xrcd_tree_mutex);
1049         kobject_init(&uverbs_dev->kobj, &ib_uverbs_dev_ktype);
1050         mutex_init(&uverbs_dev->lists_mutex);
1051         INIT_LIST_HEAD(&uverbs_dev->uverbs_file_list);
1052         INIT_LIST_HEAD(&uverbs_dev->uverbs_events_file_list);
1053
1054         devnum = find_first_zero_bit(dev_map, IB_UVERBS_MAX_DEVICES);
1055         if (devnum >= IB_UVERBS_MAX_DEVICES)
1056                 goto err;
1057         uverbs_dev->devnum = devnum;
1058         set_bit(devnum, dev_map);
1059         if (devnum >= IB_UVERBS_NUM_FIXED_MINOR)
1060                 base = dynamic_uverbs_dev + devnum - IB_UVERBS_NUM_FIXED_MINOR;
1061         else
1062                 base = IB_UVERBS_BASE_DEV + devnum;
1063
1064         rcu_assign_pointer(uverbs_dev->ib_dev, device);
1065         uverbs_dev->num_comp_vectors = device->num_comp_vectors;
1066
1067         cdev_init(&uverbs_dev->cdev, NULL);
1068         uverbs_dev->cdev.owner = THIS_MODULE;
1069         uverbs_dev->cdev.ops = device->mmap ? &uverbs_mmap_fops : &uverbs_fops;
1070         cdev_set_parent(&uverbs_dev->cdev, &uverbs_dev->kobj);
1071         kobject_set_name(&uverbs_dev->cdev.kobj, "uverbs%d", uverbs_dev->devnum);
1072         if (cdev_add(&uverbs_dev->cdev, base, 1))
1073                 goto err_cdev;
1074
1075         uverbs_dev->dev = device_create(uverbs_class, device->dev.parent,
1076                                         uverbs_dev->cdev.dev, uverbs_dev,
1077                                         "uverbs%d", uverbs_dev->devnum);
1078         if (IS_ERR(uverbs_dev->dev))
1079                 goto err_cdev;
1080
1081         if (device_create_file(uverbs_dev->dev, &dev_attr_ibdev))
1082                 goto err_class;
1083         if (device_create_file(uverbs_dev->dev, &dev_attr_abi_version))
1084                 goto err_class;
1085
1086         if (!device->specs_root) {
1087                 const struct uverbs_object_tree_def *default_root[] = {
1088                         uverbs_default_get_objects()};
1089
1090                 uverbs_dev->specs_root = uverbs_alloc_spec_tree(1,
1091                                                                 default_root);
1092                 if (IS_ERR(uverbs_dev->specs_root))
1093                         goto err_class;
1094
1095                 device->specs_root = uverbs_dev->specs_root;
1096         }
1097
1098         ib_set_client_data(device, &uverbs_client, uverbs_dev);
1099
1100         return;
1101
1102 err_class:
1103         device_destroy(uverbs_class, uverbs_dev->cdev.dev);
1104
1105 err_cdev:
1106         cdev_del(&uverbs_dev->cdev);
1107         clear_bit(devnum, dev_map);
1108
1109 err:
1110         if (atomic_dec_and_test(&uverbs_dev->refcount))
1111                 ib_uverbs_comp_dev(uverbs_dev);
1112         wait_for_completion(&uverbs_dev->comp);
1113         kobject_put(&uverbs_dev->kobj);
1114         return;
1115 }
1116
1117 static void ib_uverbs_free_hw_resources(struct ib_uverbs_device *uverbs_dev,
1118                                         struct ib_device *ib_dev)
1119 {
1120         struct ib_uverbs_file *file;
1121         struct ib_uverbs_async_event_file *event_file;
1122         struct ib_event event;
1123
1124         /* Pending running commands to terminate */
1125         synchronize_srcu(&uverbs_dev->disassociate_srcu);
1126         event.event = IB_EVENT_DEVICE_FATAL;
1127         event.element.port_num = 0;
1128         event.device = ib_dev;
1129
1130         mutex_lock(&uverbs_dev->lists_mutex);
1131         while (!list_empty(&uverbs_dev->uverbs_file_list)) {
1132                 struct ib_ucontext *ucontext;
1133                 file = list_first_entry(&uverbs_dev->uverbs_file_list,
1134                                         struct ib_uverbs_file, list);
1135                 file->is_closed = 1;
1136                 list_del(&file->list);
1137                 kref_get(&file->ref);
1138                 mutex_unlock(&uverbs_dev->lists_mutex);
1139
1140
1141                 mutex_lock(&file->cleanup_mutex);
1142                 ucontext = file->ucontext;
1143                 file->ucontext = NULL;
1144                 mutex_unlock(&file->cleanup_mutex);
1145
1146                 /* At this point ib_uverbs_close cannot be running
1147                  * ib_uverbs_cleanup_ucontext
1148                  */
1149                 if (ucontext) {
1150                         /* We must release the mutex before going ahead and
1151                          * calling disassociate_ucontext. disassociate_ucontext
1152                          * might end up indirectly calling uverbs_close,
1153                          * for example due to freeing the resources
1154                          * (e.g mmput).
1155                          */
1156                         ib_uverbs_event_handler(&file->event_handler, &event);
1157                         ib_dev->disassociate_ucontext(ucontext);
1158                         mutex_lock(&file->cleanup_mutex);
1159                         ib_uverbs_cleanup_ucontext(file, ucontext, true);
1160                         mutex_unlock(&file->cleanup_mutex);
1161                 }
1162
1163                 mutex_lock(&uverbs_dev->lists_mutex);
1164                 kref_put(&file->ref, ib_uverbs_release_file);
1165         }
1166
1167         while (!list_empty(&uverbs_dev->uverbs_events_file_list)) {
1168                 event_file = list_first_entry(&uverbs_dev->
1169                                               uverbs_events_file_list,
1170                                               struct ib_uverbs_async_event_file,
1171                                               list);
1172                 spin_lock_irq(&event_file->ev_queue.lock);
1173                 event_file->ev_queue.is_closed = 1;
1174                 spin_unlock_irq(&event_file->ev_queue.lock);
1175
1176                 list_del(&event_file->list);
1177                 ib_unregister_event_handler(
1178                         &event_file->uverbs_file->event_handler);
1179                 event_file->uverbs_file->event_handler.device =
1180                         NULL;
1181
1182                 wake_up_interruptible(&event_file->ev_queue.poll_wait);
1183                 kill_fasync(&event_file->ev_queue.async_queue, SIGIO, POLL_IN);
1184         }
1185         mutex_unlock(&uverbs_dev->lists_mutex);
1186 }
1187
1188 static void ib_uverbs_remove_one(struct ib_device *device, void *client_data)
1189 {
1190         struct ib_uverbs_device *uverbs_dev = client_data;
1191         int wait_clients = 1;
1192
1193         if (!uverbs_dev)
1194                 return;
1195
1196         dev_set_drvdata(uverbs_dev->dev, NULL);
1197         device_destroy(uverbs_class, uverbs_dev->cdev.dev);
1198         cdev_del(&uverbs_dev->cdev);
1199         clear_bit(uverbs_dev->devnum, dev_map);
1200
1201         if (device->disassociate_ucontext) {
1202                 /* We disassociate HW resources and immediately return.
1203                  * Userspace will see a EIO errno for all future access.
1204                  * Upon returning, ib_device may be freed internally and is not
1205                  * valid any more.
1206                  * uverbs_device is still available until all clients close
1207                  * their files, then the uverbs device ref count will be zero
1208                  * and its resources will be freed.
1209                  * Note: At this point no more files can be opened since the
1210                  * cdev was deleted, however active clients can still issue
1211                  * commands and close their open files.
1212                  */
1213                 rcu_assign_pointer(uverbs_dev->ib_dev, NULL);
1214                 ib_uverbs_free_hw_resources(uverbs_dev, device);
1215                 wait_clients = 0;
1216         }
1217
1218         if (atomic_dec_and_test(&uverbs_dev->refcount))
1219                 ib_uverbs_comp_dev(uverbs_dev);
1220         if (wait_clients)
1221                 wait_for_completion(&uverbs_dev->comp);
1222         if (uverbs_dev->specs_root) {
1223                 uverbs_free_spec_tree(uverbs_dev->specs_root);
1224                 device->specs_root = NULL;
1225         }
1226
1227         kobject_put(&uverbs_dev->kobj);
1228 }
1229
1230 static char *uverbs_devnode(struct device *dev, umode_t *mode)
1231 {
1232         if (mode)
1233                 *mode = 0666;
1234         return kasprintf(GFP_KERNEL, "infiniband/%s", dev_name(dev));
1235 }
1236
1237 static int __init ib_uverbs_init(void)
1238 {
1239         int ret;
1240
1241         ret = register_chrdev_region(IB_UVERBS_BASE_DEV,
1242                                      IB_UVERBS_NUM_FIXED_MINOR,
1243                                      "infiniband_verbs");
1244         if (ret) {
1245                 pr_err("user_verbs: couldn't register device number\n");
1246                 goto out;
1247         }
1248
1249         ret = alloc_chrdev_region(&dynamic_uverbs_dev, 0,
1250                                   IB_UVERBS_NUM_DYNAMIC_MINOR,
1251                                   "infiniband_verbs");
1252         if (ret) {
1253                 pr_err("couldn't register dynamic device number\n");
1254                 goto out_alloc;
1255         }
1256
1257         uverbs_class = class_create(THIS_MODULE, "infiniband_verbs");
1258         if (IS_ERR(uverbs_class)) {
1259                 ret = PTR_ERR(uverbs_class);
1260                 pr_err("user_verbs: couldn't create class infiniband_verbs\n");
1261                 goto out_chrdev;
1262         }
1263
1264         uverbs_class->devnode = uverbs_devnode;
1265
1266         ret = class_create_file(uverbs_class, &class_attr_abi_version.attr);
1267         if (ret) {
1268                 pr_err("user_verbs: couldn't create abi_version attribute\n");
1269                 goto out_class;
1270         }
1271
1272         ret = ib_register_client(&uverbs_client);
1273         if (ret) {
1274                 pr_err("user_verbs: couldn't register client\n");
1275                 goto out_class;
1276         }
1277
1278         return 0;
1279
1280 out_class:
1281         class_destroy(uverbs_class);
1282
1283 out_chrdev:
1284         unregister_chrdev_region(dynamic_uverbs_dev,
1285                                  IB_UVERBS_NUM_DYNAMIC_MINOR);
1286
1287 out_alloc:
1288         unregister_chrdev_region(IB_UVERBS_BASE_DEV,
1289                                  IB_UVERBS_NUM_FIXED_MINOR);
1290
1291 out:
1292         return ret;
1293 }
1294
1295 static void __exit ib_uverbs_cleanup(void)
1296 {
1297         ib_unregister_client(&uverbs_client);
1298         class_destroy(uverbs_class);
1299         unregister_chrdev_region(IB_UVERBS_BASE_DEV,
1300                                  IB_UVERBS_NUM_FIXED_MINOR);
1301         unregister_chrdev_region(dynamic_uverbs_dev,
1302                                  IB_UVERBS_NUM_DYNAMIC_MINOR);
1303 }
1304
1305 module_init(ib_uverbs_init);
1306 module_exit(ib_uverbs_cleanup);