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 <asm/uaccess.h>
  50
  51 #include <rdma/ib.h>
  52
  53 #include "uverbs.h"
  54
  55 MODULE_AUTHOR("Roland Dreier");
  56 MODULE_DESCRIPTION("InfiniBand userspace verbs access");
  57 MODULE_LICENSE("Dual BSD/GPL");
  58
  59 enum {
  60         IB_UVERBS_MAJOR       = 231,
  61         IB_UVERBS_BASE_MINOR  = 192,
  62         IB_UVERBS_MAX_DEVICES = 32
  63 };
  64
  65 #define IB_UVERBS_BASE_DEV      MKDEV(IB_UVERBS_MAJOR, IB_UVERBS_BASE_MINOR)
  66
  67 static struct class *uverbs_class;
  68
  69 DEFINE_SPINLOCK(ib_uverbs_idr_lock);
  70 DEFINE_IDR(ib_uverbs_pd_idr);
  71 DEFINE_IDR(ib_uverbs_mr_idr);
  72 DEFINE_IDR(ib_uverbs_mw_idr);
  73 DEFINE_IDR(ib_uverbs_ah_idr);
  74 DEFINE_IDR(ib_uverbs_cq_idr);
  75 DEFINE_IDR(ib_uverbs_qp_idr);
  76 DEFINE_IDR(ib_uverbs_srq_idr);
  77 DEFINE_IDR(ib_uverbs_xrcd_idr);
  78 DEFINE_IDR(ib_uverbs_rule_idr);
  79 DEFINE_IDR(ib_uverbs_wq_idr);
  80
  81 static DEFINE_SPINLOCK(map_lock);
  82 static DECLARE_BITMAP(dev_map, IB_UVERBS_MAX_DEVICES);
  83
  84 static ssize_t (*uverbs_cmd_table[])(struct ib_uverbs_file *file,
  85                                      struct ib_device *ib_dev,
  86                                      const char __user *buf, int in_len,
  87                                      int out_len) = {
  88         [IB_USER_VERBS_CMD_GET_CONTEXT]         = ib_uverbs_get_context,
  89         [IB_USER_VERBS_CMD_QUERY_DEVICE]        = ib_uverbs_query_device,
  90         [IB_USER_VERBS_CMD_QUERY_PORT]          = ib_uverbs_query_port,
  91         [IB_USER_VERBS_CMD_ALLOC_PD]            = ib_uverbs_alloc_pd,
  92         [IB_USER_VERBS_CMD_DEALLOC_PD]          = ib_uverbs_dealloc_pd,
  93         [IB_USER_VERBS_CMD_REG_MR]              = ib_uverbs_reg_mr,
  94         [IB_USER_VERBS_CMD_REREG_MR]            = ib_uverbs_rereg_mr,
  95         [IB_USER_VERBS_CMD_DEREG_MR]            = ib_uverbs_dereg_mr,
  96         [IB_USER_VERBS_CMD_ALLOC_MW]            = ib_uverbs_alloc_mw,
  97         [IB_USER_VERBS_CMD_DEALLOC_MW]          = ib_uverbs_dealloc_mw,
  98         [IB_USER_VERBS_CMD_CREATE_COMP_CHANNEL] = ib_uverbs_create_comp_channel,
  99         [IB_USER_VERBS_CMD_CREATE_CQ]           = ib_uverbs_create_cq,
 100         [IB_USER_VERBS_CMD_RESIZE_CQ]           = ib_uverbs_resize_cq,
 101         [IB_USER_VERBS_CMD_POLL_CQ]             = ib_uverbs_poll_cq,
 102         [IB_USER_VERBS_CMD_REQ_NOTIFY_CQ]       = ib_uverbs_req_notify_cq,
 103         [IB_USER_VERBS_CMD_DESTROY_CQ]          = ib_uverbs_destroy_cq,
 104         [IB_USER_VERBS_CMD_CREATE_QP]           = ib_uverbs_create_qp,
 105         [IB_USER_VERBS_CMD_QUERY_QP]            = ib_uverbs_query_qp,
 106         [IB_USER_VERBS_CMD_MODIFY_QP]           = ib_uverbs_modify_qp,
 107         [IB_USER_VERBS_CMD_DESTROY_QP]          = ib_uverbs_destroy_qp,
 108         [IB_USER_VERBS_CMD_POST_SEND]           = ib_uverbs_post_send,
 109         [IB_USER_VERBS_CMD_POST_RECV]           = ib_uverbs_post_recv,
 110         [IB_USER_VERBS_CMD_POST_SRQ_RECV]       = ib_uverbs_post_srq_recv,
 111         [IB_USER_VERBS_CMD_CREATE_AH]           = ib_uverbs_create_ah,
 112         [IB_USER_VERBS_CMD_DESTROY_AH]          = ib_uverbs_destroy_ah,
 113         [IB_USER_VERBS_CMD_ATTACH_MCAST]        = ib_uverbs_attach_mcast,
 114         [IB_USER_VERBS_CMD_DETACH_MCAST]        = ib_uverbs_detach_mcast,
 115         [IB_USER_VERBS_CMD_CREATE_SRQ]          = ib_uverbs_create_srq,
 116         [IB_USER_VERBS_CMD_MODIFY_SRQ]          = ib_uverbs_modify_srq,
 117         [IB_USER_VERBS_CMD_QUERY_SRQ]           = ib_uverbs_query_srq,
 118         [IB_USER_VERBS_CMD_DESTROY_SRQ]         = ib_uverbs_destroy_srq,
 119         [IB_USER_VERBS_CMD_OPEN_XRCD]           = ib_uverbs_open_xrcd,
 120         [IB_USER_VERBS_CMD_CLOSE_XRCD]          = ib_uverbs_close_xrcd,
 121         [IB_USER_VERBS_CMD_CREATE_XSRQ]         = ib_uverbs_create_xsrq,
 122         [IB_USER_VERBS_CMD_OPEN_QP]             = ib_uverbs_open_qp,
 123 };
 124
 125 static int (*uverbs_ex_cmd_table[])(struct ib_uverbs_file *file,
 126                                     struct ib_device *ib_dev,
 127                                     struct ib_udata *ucore,
 128                                     struct ib_udata *uhw) = {
 129         [IB_USER_VERBS_EX_CMD_CREATE_FLOW]      = ib_uverbs_ex_create_flow,
 130         [IB_USER_VERBS_EX_CMD_DESTROY_FLOW]     = ib_uverbs_ex_destroy_flow,
 131         [IB_USER_VERBS_EX_CMD_QUERY_DEVICE]     = ib_uverbs_ex_query_device,
 132         [IB_USER_VERBS_EX_CMD_CREATE_CQ]        = ib_uverbs_ex_create_cq,
 133         [IB_USER_VERBS_EX_CMD_CREATE_QP]        = ib_uverbs_ex_create_qp,
 134         [IB_USER_VERBS_EX_CMD_CREATE_WQ]        = ib_uverbs_ex_create_wq,
 135         [IB_USER_VERBS_EX_CMD_MODIFY_WQ]        = ib_uverbs_ex_modify_wq,
 136         [IB_USER_VERBS_EX_CMD_DESTROY_WQ]       = ib_uverbs_ex_destroy_wq,
 137 };
 138
 139 static void ib_uverbs_add_one(struct ib_device *device);
 140 static void ib_uverbs_remove_one(struct ib_device *device, void *client_data);
 141
 142 int uverbs_dealloc_mw(struct ib_mw *mw)
 143 {
 144         struct ib_pd *pd = mw->pd;
 145         int ret;
 146
 147         ret = mw->device->dealloc_mw(mw);
 148         if (!ret)
 149                 atomic_dec(&pd->usecnt);
 150         return ret;
 151 }
 152
 153 static void ib_uverbs_release_dev(struct kobject *kobj)
 154 {
 155         struct ib_uverbs_device *dev =
 156                 container_of(kobj, struct ib_uverbs_device, kobj);
 157
 158         cleanup_srcu_struct(&dev->disassociate_srcu);
 159         kfree(dev);
 160 }
 161
 162 static struct kobj_type ib_uverbs_dev_ktype = {
 163         .release = ib_uverbs_release_dev,
 164 };
 165
 166 static void ib_uverbs_release_event_file(struct kref *ref)
 167 {
 168         struct ib_uverbs_event_file *file =
 169                 container_of(ref, struct ib_uverbs_event_file, ref);
 170
 171         kfree(file);
 172 }
 173
 174 void ib_uverbs_release_ucq(struct ib_uverbs_file *file,
 175                           struct ib_uverbs_event_file *ev_file,
 176                           struct ib_ucq_object *uobj)
 177 {
 178         struct ib_uverbs_event *evt, *tmp;
 179
 180         if (ev_file) {
 181                 spin_lock_irq(&ev_file->lock);
 182                 list_for_each_entry_safe(evt, tmp, &uobj->comp_list, obj_list) {
 183                         list_del(&evt->list);
 184                         kfree(evt);
 185                 }
 186                 spin_unlock_irq(&ev_file->lock);
 187
 188                 kref_put(&ev_file->ref, ib_uverbs_release_event_file);
 189         }
 190
 191         spin_lock_irq(&file->async_file->lock);
 192         list_for_each_entry_safe(evt, tmp, &uobj->async_list, obj_list) {
 193                 list_del(&evt->list);
 194                 kfree(evt);
 195         }
 196         spin_unlock_irq(&file->async_file->lock);
 197 }
 198
 199 void ib_uverbs_release_uevent(struct ib_uverbs_file *file,
 200                               struct ib_uevent_object *uobj)
 201 {
 202         struct ib_uverbs_event *evt, *tmp;
 203
 204         spin_lock_irq(&file->async_file->lock);
 205         list_for_each_entry_safe(evt, tmp, &uobj->event_list, obj_list) {
 206                 list_del(&evt->list);
 207                 kfree(evt);
 208         }
 209         spin_unlock_irq(&file->async_file->lock);
 210 }
 211
 212 static void ib_uverbs_detach_umcast(struct ib_qp *qp,
 213                                     struct ib_uqp_object *uobj)
 214 {
 215         struct ib_uverbs_mcast_entry *mcast, *tmp;
 216
 217         list_for_each_entry_safe(mcast, tmp, &uobj->mcast_list, list) {
 218                 ib_detach_mcast(qp, &mcast->gid, mcast->lid);
 219                 list_del(&mcast->list);
 220                 kfree(mcast);
 221         }
 222 }
 223
 224 static int ib_uverbs_cleanup_ucontext(struct ib_uverbs_file *file,
 225                                       struct ib_ucontext *context)
 226 {
 227         struct ib_uobject *uobj, *tmp;
 228
 229         context->closing = 1;
 230
 231         list_for_each_entry_safe(uobj, tmp, &context->ah_list, list) {
 232                 struct ib_ah *ah = uobj->object;
 233
 234                 idr_remove_uobj(&ib_uverbs_ah_idr, uobj);
 235                 ib_destroy_ah(ah);
 236                 kfree(uobj);
 237         }
 238
 239         /* Remove MWs before QPs, in order to support type 2A MWs. */
 240         list_for_each_entry_safe(uobj, tmp, &context->mw_list, list) {
 241                 struct ib_mw *mw = uobj->object;
 242
 243                 idr_remove_uobj(&ib_uverbs_mw_idr, uobj);
 244                 uverbs_dealloc_mw(mw);
 245                 kfree(uobj);
 246         }
 247
 248         list_for_each_entry_safe(uobj, tmp, &context->rule_list, list) {
 249                 struct ib_flow *flow_id = uobj->object;
 250
 251                 idr_remove_uobj(&ib_uverbs_rule_idr, uobj);
 252                 ib_destroy_flow(flow_id);
 253                 kfree(uobj);
 254         }
 255
 256         list_for_each_entry_safe(uobj, tmp, &context->qp_list, list) {
 257                 struct ib_qp *qp = uobj->object;
 258                 struct ib_uqp_object *uqp =
 259                         container_of(uobj, struct ib_uqp_object, uevent.uobject);
 260
 261                 idr_remove_uobj(&ib_uverbs_qp_idr, uobj);
 262                 if (qp != qp->real_qp) {
 263                         ib_close_qp(qp);
 264                 } else {
 265                         ib_uverbs_detach_umcast(qp, uqp);
 266                         ib_destroy_qp(qp);
 267                 }
 268                 ib_uverbs_release_uevent(file, &uqp->uevent);
 269                 kfree(uqp);
 270         }
 271
 272         list_for_each_entry_safe(uobj, tmp, &context->wq_list, list) {
 273                 struct ib_wq *wq = uobj->object;
 274                 struct ib_uwq_object *uwq =
 275                         container_of(uobj, struct ib_uwq_object, uevent.uobject);
 276
 277                 idr_remove_uobj(&ib_uverbs_wq_idr, uobj);
 278                 ib_destroy_wq(wq);
 279                 ib_uverbs_release_uevent(file, &uwq->uevent);
 280                 kfree(uwq);
 281         }
 282
 283         list_for_each_entry_safe(uobj, tmp, &context->srq_list, list) {
 284                 struct ib_srq *srq = uobj->object;
 285                 struct ib_uevent_object *uevent =
 286                         container_of(uobj, struct ib_uevent_object, uobject);
 287
 288                 idr_remove_uobj(&ib_uverbs_srq_idr, uobj);
 289                 ib_destroy_srq(srq);
 290                 ib_uverbs_release_uevent(file, uevent);
 291                 kfree(uevent);
 292         }
 293
 294         list_for_each_entry_safe(uobj, tmp, &context->cq_list, list) {
 295                 struct ib_cq *cq = uobj->object;
 296                 struct ib_uverbs_event_file *ev_file = cq->cq_context;
 297                 struct ib_ucq_object *ucq =
 298                         container_of(uobj, struct ib_ucq_object, uobject);
 299
 300                 idr_remove_uobj(&ib_uverbs_cq_idr, uobj);
 301                 ib_destroy_cq(cq);
 302                 ib_uverbs_release_ucq(file, ev_file, ucq);
 303                 kfree(ucq);
 304         }
 305
 306         list_for_each_entry_safe(uobj, tmp, &context->mr_list, list) {
 307                 struct ib_mr *mr = uobj->object;
 308
 309                 idr_remove_uobj(&ib_uverbs_mr_idr, uobj);
 310                 ib_dereg_mr(mr);
 311                 kfree(uobj);
 312         }
 313
 314         mutex_lock(&file->device->xrcd_tree_mutex);
 315         list_for_each_entry_safe(uobj, tmp, &context->xrcd_list, list) {
 316                 struct ib_xrcd *xrcd = uobj->object;
 317                 struct ib_uxrcd_object *uxrcd =
 318                         container_of(uobj, struct ib_uxrcd_object, uobject);
 319
 320                 idr_remove_uobj(&ib_uverbs_xrcd_idr, uobj);
 321                 ib_uverbs_dealloc_xrcd(file->device, xrcd);
 322                 kfree(uxrcd);
 323         }
 324         mutex_unlock(&file->device->xrcd_tree_mutex);
 325
 326         list_for_each_entry_safe(uobj, tmp, &context->pd_list, list) {
 327                 struct ib_pd *pd = uobj->object;
 328
 329                 idr_remove_uobj(&ib_uverbs_pd_idr, uobj);
 330                 ib_dealloc_pd(pd);
 331                 kfree(uobj);
 332         }
 333
 334         put_pid(context->tgid);
 335
 336         return context->device->dealloc_ucontext(context);
 337 }
 338
 339 static void ib_uverbs_comp_dev(struct ib_uverbs_device *dev)
 340 {
 341         complete(&dev->comp);
 342 }
 343
 344 static void ib_uverbs_release_file(struct kref *ref)
 345 {
 346         struct ib_uverbs_file *file =
 347                 container_of(ref, struct ib_uverbs_file, ref);
 348         struct ib_device *ib_dev;
 349         int srcu_key;
 350
 351         srcu_key = srcu_read_lock(&file->device->disassociate_srcu);
 352         ib_dev = srcu_dereference(file->device->ib_dev,
 353                                   &file->device->disassociate_srcu);
 354         if (ib_dev && !ib_dev->disassociate_ucontext)
 355                 module_put(ib_dev->owner);
 356         srcu_read_unlock(&file->device->disassociate_srcu, srcu_key);
 357
 358         if (atomic_dec_and_test(&file->device->refcount))
 359                 ib_uverbs_comp_dev(file->device);
 360
 361         kfree(file);
 362 }
 363
 364 static ssize_t ib_uverbs_event_read(struct file *filp, char __user *buf,
 365                                     size_t count, loff_t *pos)
 366 {
 367         struct ib_uverbs_event_file *file = filp->private_data;
 368         struct ib_uverbs_event *event;
 369         int eventsz;
 370         int ret = 0;
 371
 372         spin_lock_irq(&file->lock);
 373
 374         while (list_empty(&file->event_list)) {
 375                 spin_unlock_irq(&file->lock);
 376
 377                 if (filp->f_flags & O_NONBLOCK)
 378                         return -EAGAIN;
 379
 380                 if (wait_event_interruptible(file->poll_wait,
 381                                              (!list_empty(&file->event_list) ||
 382                         /* The barriers built into wait_event_interruptible()
 383                          * and wake_up() guarentee this will see the null set
 384                          * without using RCU
 385                          */
 386                                              !file->uverbs_file->device->ib_dev)))
 387                         return -ERESTARTSYS;
 388
 389                 /* If device was disassociated and no event exists set an error */
 390                 if (list_empty(&file->event_list) &&
 391                     !file->uverbs_file->device->ib_dev)
 392                         return -EIO;
 393
 394                 spin_lock_irq(&file->lock);
 395         }
 396
 397         event = list_entry(file->event_list.next, struct ib_uverbs_event, list);
 398
 399         if (file->is_async)
 400                 eventsz = sizeof (struct ib_uverbs_async_event_desc);
 401         else
 402                 eventsz = sizeof (struct ib_uverbs_comp_event_desc);
 403
 404         if (eventsz > count) {
 405                 ret   = -EINVAL;
 406                 event = NULL;
 407         } else {
 408                 list_del(file->event_list.next);
 409                 if (event->counter) {
 410                         ++(*event->counter);
 411                         list_del(&event->obj_list);
 412                 }
 413         }
 414
 415         spin_unlock_irq(&file->lock);
 416
 417         if (event) {
 418                 if (copy_to_user(buf, event, eventsz))
 419                         ret = -EFAULT;
 420                 else
 421                         ret = eventsz;
 422         }
 423
 424         kfree(event);
 425
 426         return ret;
 427 }
 428
 429 static unsigned int ib_uverbs_event_poll(struct file *filp,
 430                                          struct poll_table_struct *wait)
 431 {
 432         unsigned int pollflags = 0;
 433         struct ib_uverbs_event_file *file = filp->private_data;
 434
 435         poll_wait(filp, &file->poll_wait, wait);
 436
 437         spin_lock_irq(&file->lock);
 438         if (!list_empty(&file->event_list))
 439                 pollflags = POLLIN | POLLRDNORM;
 440         spin_unlock_irq(&file->lock);
 441
 442         return pollflags;
 443 }
 444
 445 static int ib_uverbs_event_fasync(int fd, struct file *filp, int on)
 446 {
 447         struct ib_uverbs_event_file *file = filp->private_data;
 448
 449         return fasync_helper(fd, filp, on, &file->async_queue);
 450 }
 451
 452 static int ib_uverbs_event_close(struct inode *inode, struct file *filp)
 453 {
 454         struct ib_uverbs_event_file *file = filp->private_data;
 455         struct ib_uverbs_event *entry, *tmp;
 456         int closed_already = 0;
 457
 458         mutex_lock(&file->uverbs_file->device->lists_mutex);
 459         spin_lock_irq(&file->lock);
 460         closed_already = file->is_closed;
 461         file->is_closed = 1;
 462         list_for_each_entry_safe(entry, tmp, &file->event_list, list) {
 463                 if (entry->counter)
 464                         list_del(&entry->obj_list);
 465                 kfree(entry);
 466         }
 467         spin_unlock_irq(&file->lock);
 468         if (!closed_already) {
 469                 list_del(&file->list);
 470                 if (file->is_async)
 471                         ib_unregister_event_handler(&file->uverbs_file->
 472                                 event_handler);
 473         }
 474         mutex_unlock(&file->uverbs_file->device->lists_mutex);
 475
 476         kref_put(&file->uverbs_file->ref, ib_uverbs_release_file);
 477         kref_put(&file->ref, ib_uverbs_release_event_file);
 478
 479         return 0;
 480 }
 481
 482 static const struct file_operations uverbs_event_fops = {
 483         .owner   = THIS_MODULE,
 484         .read    = ib_uverbs_event_read,
 485         .poll    = ib_uverbs_event_poll,
 486         .release = ib_uverbs_event_close,
 487         .fasync  = ib_uverbs_event_fasync,
 488         .llseek  = no_llseek,
 489 };
 490
 491 void ib_uverbs_comp_handler(struct ib_cq *cq, void *cq_context)
 492 {
 493         struct ib_uverbs_event_file    *file = cq_context;
 494         struct ib_ucq_object           *uobj;
 495         struct ib_uverbs_event         *entry;
 496         unsigned long                   flags;
 497
 498         if (!file)
 499                 return;
 500
 501         spin_lock_irqsave(&file->lock, flags);
 502         if (file->is_closed) {
 503                 spin_unlock_irqrestore(&file->lock, flags);
 504                 return;
 505         }
 506
 507         entry = kmalloc(sizeof *entry, GFP_ATOMIC);
 508         if (!entry) {
 509                 spin_unlock_irqrestore(&file->lock, flags);
 510                 return;
 511         }
 512
 513         uobj = container_of(cq->uobject, struct ib_ucq_object, uobject);
 514
 515         entry->desc.comp.cq_handle = cq->uobject->user_handle;
 516         entry->counter             = &uobj->comp_events_reported;
 517
 518         list_add_tail(&entry->list, &file->event_list);
 519         list_add_tail(&entry->obj_list, &uobj->comp_list);
 520         spin_unlock_irqrestore(&file->lock, flags);
 521
 522         wake_up_interruptible(&file->poll_wait);
 523         kill_fasync(&file->async_queue, SIGIO, POLL_IN);
 524 }
 525
 526 static void ib_uverbs_async_handler(struct ib_uverbs_file *file,
 527                                     __u64 element, __u64 event,
 528                                     struct list_head *obj_list,
 529                                     u32 *counter)
 530 {
 531         struct ib_uverbs_event *entry;
 532         unsigned long flags;
 533
 534         spin_lock_irqsave(&file->async_file->lock, flags);
 535         if (file->async_file->is_closed) {
 536                 spin_unlock_irqrestore(&file->async_file->lock, flags);
 537                 return;
 538         }
 539
 540         entry = kmalloc(sizeof *entry, GFP_ATOMIC);
 541         if (!entry) {
 542                 spin_unlock_irqrestore(&file->async_file->lock, flags);
 543                 return;
 544         }
 545
 546         entry->desc.async.element    = element;
 547         entry->desc.async.event_type = event;
 548         entry->desc.async.reserved   = 0;
 549         entry->counter               = counter;
 550
 551         list_add_tail(&entry->list, &file->async_file->event_list);
 552         if (obj_list)
 553                 list_add_tail(&entry->obj_list, obj_list);
 554         spin_unlock_irqrestore(&file->async_file->lock, flags);
 555
 556         wake_up_interruptible(&file->async_file->poll_wait);
 557         kill_fasync(&file->async_file->async_queue, SIGIO, POLL_IN);
 558 }
 559
 560 void ib_uverbs_cq_event_handler(struct ib_event *event, void *context_ptr)
 561 {
 562         struct ib_ucq_object *uobj = container_of(event->element.cq->uobject,
 563                                                   struct ib_ucq_object, uobject);
 564
 565         ib_uverbs_async_handler(uobj->uverbs_file, uobj->uobject.user_handle,
 566                                 event->event, &uobj->async_list,
 567                                 &uobj->async_events_reported);
 568 }
 569
 570 void ib_uverbs_qp_event_handler(struct ib_event *event, void *context_ptr)
 571 {
 572         struct ib_uevent_object *uobj;
 573
 574         /* for XRC target qp's, check that qp is live */
 575         if (!event->element.qp->uobject || !event->element.qp->uobject->live)
 576                 return;
 577
 578         uobj = container_of(event->element.qp->uobject,
 579                             struct ib_uevent_object, uobject);
 580
 581         ib_uverbs_async_handler(context_ptr, uobj->uobject.user_handle,
 582                                 event->event, &uobj->event_list,
 583                                 &uobj->events_reported);
 584 }
 585
 586 void ib_uverbs_wq_event_handler(struct ib_event *event, void *context_ptr)
 587 {
 588         struct ib_uevent_object *uobj = container_of(event->element.wq->uobject,
 589                                                   struct ib_uevent_object, uobject);
 590
 591         ib_uverbs_async_handler(context_ptr, uobj->uobject.user_handle,
 592                                 event->event, &uobj->event_list,
 593                                 &uobj->events_reported);
 594 }
 595
 596 void ib_uverbs_srq_event_handler(struct ib_event *event, void *context_ptr)
 597 {
 598         struct ib_uevent_object *uobj;
 599
 600         uobj = container_of(event->element.srq->uobject,
 601                             struct ib_uevent_object, uobject);
 602
 603         ib_uverbs_async_handler(context_ptr, uobj->uobject.user_handle,
 604                                 event->event, &uobj->event_list,
 605                                 &uobj->events_reported);
 606 }
 607
 608 void ib_uverbs_event_handler(struct ib_event_handler *handler,
 609                              struct ib_event *event)
 610 {
 611         struct ib_uverbs_file *file =
 612                 container_of(handler, struct ib_uverbs_file, event_handler);
 613
 614         ib_uverbs_async_handler(file, event->element.port_num, event->event,
 615                                 NULL, NULL);
 616 }
 617
 618 void ib_uverbs_free_async_event_file(struct ib_uverbs_file *file)
 619 {
 620         kref_put(&file->async_file->ref, ib_uverbs_release_event_file);
 621         file->async_file = NULL;
 622 }
 623
 624 struct file *ib_uverbs_alloc_event_file(struct ib_uverbs_file *uverbs_file,
 625                                         struct ib_device        *ib_dev,
 626                                         int is_async)
 627 {
 628         struct ib_uverbs_event_file *ev_file;
 629         struct file *filp;
 630         int ret;
 631
 632         ev_file = kzalloc(sizeof(*ev_file), GFP_KERNEL);
 633         if (!ev_file)
 634                 return ERR_PTR(-ENOMEM);
 635
 636         kref_init(&ev_file->ref);
 637         spin_lock_init(&ev_file->lock);
 638         INIT_LIST_HEAD(&ev_file->event_list);
 639         init_waitqueue_head(&ev_file->poll_wait);
 640         ev_file->uverbs_file = uverbs_file;
 641         kref_get(&ev_file->uverbs_file->ref);
 642         ev_file->async_queue = NULL;
 643         ev_file->is_closed   = 0;
 644
 645         filp = anon_inode_getfile("[infinibandevent]", &uverbs_event_fops,
 646                                   ev_file, O_RDONLY);
 647         if (IS_ERR(filp))
 648                 goto err_put_refs;
 649
 650         mutex_lock(&uverbs_file->device->lists_mutex);
 651         list_add_tail(&ev_file->list,
 652                       &uverbs_file->device->uverbs_events_file_list);
 653         mutex_unlock(&uverbs_file->device->lists_mutex);
 654
 655         if (is_async) {
 656                 WARN_ON(uverbs_file->async_file);
 657                 uverbs_file->async_file = ev_file;
 658                 kref_get(&uverbs_file->async_file->ref);
 659                 INIT_IB_EVENT_HANDLER(&uverbs_file->event_handler,
 660                                       ib_dev,
 661                                       ib_uverbs_event_handler);
 662                 ret = ib_register_event_handler(&uverbs_file->event_handler);
 663                 if (ret)
 664                         goto err_put_file;
 665
 666                 /* At that point async file stuff was fully set */
 667                 ev_file->is_async = 1;
 668         }
 669
 670         return filp;
 671
 672 err_put_file:
 673         fput(filp);
 674         kref_put(&uverbs_file->async_file->ref, ib_uverbs_release_event_file);
 675         uverbs_file->async_file = NULL;
 676         return ERR_PTR(ret);
 677
 678 err_put_refs:
 679         kref_put(&ev_file->uverbs_file->ref, ib_uverbs_release_file);
 680         kref_put(&ev_file->ref, ib_uverbs_release_event_file);
 681         return filp;
 682 }
 683
 684 /*
 685  * Look up a completion event file by FD.  If lookup is successful,
 686  * takes a ref to the event file struct that it returns; if
 687  * unsuccessful, returns NULL.
 688  */
 689 struct ib_uverbs_event_file *ib_uverbs_lookup_comp_file(int fd)
 690 {
 691         struct ib_uverbs_event_file *ev_file = NULL;
 692         struct fd f = fdget(fd);
 693
 694         if (!f.file)
 695                 return NULL;
 696
 697         if (f.file->f_op != &uverbs_event_fops)
 698                 goto out;
 699
 700         ev_file = f.file->private_data;
 701         if (ev_file->is_async) {
 702                 ev_file = NULL;
 703                 goto out;
 704         }
 705
 706         kref_get(&ev_file->ref);
 707
 708 out:
 709         fdput(f);
 710         return ev_file;
 711 }
 712
 713 static int verify_command_mask(struct ib_device *ib_dev, __u32 command)
 714 {
 715         u64 mask;
 716
 717         if (command <= IB_USER_VERBS_CMD_OPEN_QP)
 718                 mask = ib_dev->uverbs_cmd_mask;
 719         else
 720                 mask = ib_dev->uverbs_ex_cmd_mask;
 721
 722         if (mask & ((u64)1 << command))
 723                 return 0;
 724
 725         return -1;
 726 }
 727
 728 static ssize_t ib_uverbs_write(struct file *filp, const char __user *buf,
 729                              size_t count, loff_t *pos)
 730 {
 731         struct ib_uverbs_file *file = filp->private_data;
 732         struct ib_device *ib_dev;
 733         struct ib_uverbs_cmd_hdr hdr;
 734         __u32 command;
 735         __u32 flags;
 736         int srcu_key;
 737         ssize_t ret;
 738
 739         if (WARN_ON_ONCE(!ib_safe_file_access(filp)))
 740                 return -EACCES;
 741
 742         if (count < sizeof hdr)
 743                 return -EINVAL;
 744
 745         if (copy_from_user(&hdr, buf, sizeof hdr))
 746                 return -EFAULT;
 747
 748         srcu_key = srcu_read_lock(&file->device->disassociate_srcu);
 749         ib_dev = srcu_dereference(file->device->ib_dev,
 750                                   &file->device->disassociate_srcu);
 751         if (!ib_dev) {
 752                 ret = -EIO;
 753                 goto out;
 754         }
 755
 756         if (hdr.command & ~(__u32)(IB_USER_VERBS_CMD_FLAGS_MASK |
 757                                    IB_USER_VERBS_CMD_COMMAND_MASK)) {
 758                 ret = -EINVAL;
 759                 goto out;
 760         }
 761
 762         command = hdr.command & IB_USER_VERBS_CMD_COMMAND_MASK;
 763         if (verify_command_mask(ib_dev, command)) {
 764                 ret = -EOPNOTSUPP;
 765                 goto out;
 766         }
 767
 768         if (!file->ucontext &&
 769             command != IB_USER_VERBS_CMD_GET_CONTEXT) {
 770                 ret = -EINVAL;
 771                 goto out;
 772         }
 773
 774         flags = (hdr.command &
 775                  IB_USER_VERBS_CMD_FLAGS_MASK) >> IB_USER_VERBS_CMD_FLAGS_SHIFT;
 776
 777         if (!flags) {
 778                 if (command >= ARRAY_SIZE(uverbs_cmd_table) ||
 779                     !uverbs_cmd_table[command]) {
 780                         ret = -EINVAL;
 781                         goto out;
 782                 }
 783
 784                 if (hdr.in_words * 4 != count) {
 785                         ret = -EINVAL;
 786                         goto out;
 787                 }
 788
 789                 ret = uverbs_cmd_table[command](file, ib_dev,
 790                                                  buf + sizeof(hdr),
 791                                                  hdr.in_words * 4,
 792                                                  hdr.out_words * 4);
 793
 794         } else if (flags == IB_USER_VERBS_CMD_FLAG_EXTENDED) {
 795                 struct ib_uverbs_ex_cmd_hdr ex_hdr;
 796                 struct ib_udata ucore;
 797                 struct ib_udata uhw;
 798                 size_t written_count = count;
 799
 800                 if (command >= ARRAY_SIZE(uverbs_ex_cmd_table) ||
 801                     !uverbs_ex_cmd_table[command]) {
 802                         ret = -ENOSYS;
 803                         goto out;
 804                 }
 805
 806                 if (!file->ucontext) {
 807                         ret = -EINVAL;
 808                         goto out;
 809                 }
 810
 811                 if (count < (sizeof(hdr) + sizeof(ex_hdr))) {
 812                         ret = -EINVAL;
 813                         goto out;
 814                 }
 815
 816                 if (copy_from_user(&ex_hdr, buf + sizeof(hdr), sizeof(ex_hdr))) {
 817                         ret = -EFAULT;
 818                         goto out;
 819                 }
 820
 821                 count -= sizeof(hdr) + sizeof(ex_hdr);
 822                 buf += sizeof(hdr) + sizeof(ex_hdr);
 823
 824                 if ((hdr.in_words + ex_hdr.provider_in_words) * 8 != count) {
 825                         ret = -EINVAL;
 826                         goto out;
 827                 }
 828
 829                 if (ex_hdr.cmd_hdr_reserved) {
 830                         ret = -EINVAL;
 831                         goto out;
 832                 }
 833
 834                 if (ex_hdr.response) {
 835                         if (!hdr.out_words && !ex_hdr.provider_out_words) {
 836                                 ret = -EINVAL;
 837                                 goto out;
 838                         }
 839
 840                         if (!access_ok(VERIFY_WRITE,
 841                                        (void __user *) (unsigned long) ex_hdr.response,
 842                                        (hdr.out_words + ex_hdr.provider_out_words) * 8)) {
 843                                 ret = -EFAULT;
 844                                 goto out;
 845                         }
 846                 } else {
 847                         if (hdr.out_words || ex_hdr.provider_out_words) {
 848                                 ret = -EINVAL;
 849                                 goto out;
 850                         }
 851                 }
 852
 853                 INIT_UDATA_BUF_OR_NULL(&ucore, buf, (unsigned long) ex_hdr.response,
 854                                        hdr.in_words * 8, hdr.out_words * 8);
 855
 856                 INIT_UDATA_BUF_OR_NULL(&uhw,
 857                                        buf + ucore.inlen,
 858                                        (unsigned long) ex_hdr.response + ucore.outlen,
 859                                        ex_hdr.provider_in_words * 8,
 860                                        ex_hdr.provider_out_words * 8);
 861
 862                 ret = uverbs_ex_cmd_table[command](file,
 863                                                    ib_dev,
 864                                                    &ucore,
 865                                                    &uhw);
 866                 if (!ret)
 867                         ret = written_count;
 868         } else {
 869                 ret = -ENOSYS;
 870         }
 871
 872 out:
 873         srcu_read_unlock(&file->device->disassociate_srcu, srcu_key);
 874         return ret;
 875 }
 876
 877 static int ib_uverbs_mmap(struct file *filp, struct vm_area_struct *vma)
 878 {
 879         struct ib_uverbs_file *file = filp->private_data;
 880         struct ib_device *ib_dev;
 881         int ret = 0;
 882         int srcu_key;
 883
 884         srcu_key = srcu_read_lock(&file->device->disassociate_srcu);
 885         ib_dev = srcu_dereference(file->device->ib_dev,
 886                                   &file->device->disassociate_srcu);
 887         if (!ib_dev) {
 888                 ret = -EIO;
 889                 goto out;
 890         }
 891
 892         if (!file->ucontext)
 893                 ret = -ENODEV;
 894         else
 895                 ret = ib_dev->mmap(file->ucontext, vma);
 896 out:
 897         srcu_read_unlock(&file->device->disassociate_srcu, srcu_key);
 898         return ret;
 899 }
 900
 901 /*
 902  * ib_uverbs_open() does not need the BKL:
 903  *
 904  *  - the ib_uverbs_device structures are properly reference counted and
 905  *    everything else is purely local to the file being created, so
 906  *    races against other open calls are not a problem;
 907  *  - there is no ioctl method to race against;
 908  *  - the open method will either immediately run -ENXIO, or all
 909  *    required initialization will be done.
 910  */
 911 static int ib_uverbs_open(struct inode *inode, struct file *filp)
 912 {
 913         struct ib_uverbs_device *dev;
 914         struct ib_uverbs_file *file;
 915         struct ib_device *ib_dev;
 916         int ret;
 917         int module_dependent;
 918         int srcu_key;
 919
 920         dev = container_of(inode->i_cdev, struct ib_uverbs_device, cdev);
 921         if (!atomic_inc_not_zero(&dev->refcount))
 922                 return -ENXIO;
 923
 924         srcu_key = srcu_read_lock(&dev->disassociate_srcu);
 925         mutex_lock(&dev->lists_mutex);
 926         ib_dev = srcu_dereference(dev->ib_dev,
 927                                   &dev->disassociate_srcu);
 928         if (!ib_dev) {
 929                 ret = -EIO;
 930                 goto err;
 931         }
 932
 933         /* In case IB device supports disassociate ucontext, there is no hard
 934          * dependency between uverbs device and its low level device.
 935          */
 936         module_dependent = !(ib_dev->disassociate_ucontext);
 937
 938         if (module_dependent) {
 939                 if (!try_module_get(ib_dev->owner)) {
 940                         ret = -ENODEV;
 941                         goto err;
 942                 }
 943         }
 944
 945         file = kzalloc(sizeof(*file), GFP_KERNEL);
 946         if (!file) {
 947                 ret = -ENOMEM;
 948                 if (module_dependent)
 949                         goto err_module;
 950
 951                 goto err;
 952         }
 953
 954         file->device     = dev;
 955         file->ucontext   = NULL;
 956         file->async_file = NULL;
 957         kref_init(&file->ref);
 958         mutex_init(&file->mutex);
 959
 960         filp->private_data = file;
 961         kobject_get(&dev->kobj);
 962         list_add_tail(&file->list, &dev->uverbs_file_list);
 963         mutex_unlock(&dev->lists_mutex);
 964         srcu_read_unlock(&dev->disassociate_srcu, srcu_key);
 965
 966         return nonseekable_open(inode, filp);
 967
 968 err_module:
 969         module_put(ib_dev->owner);
 970
 971 err:
 972         mutex_unlock(&dev->lists_mutex);
 973         srcu_read_unlock(&dev->disassociate_srcu, srcu_key);
 974         if (atomic_dec_and_test(&dev->refcount))
 975                 ib_uverbs_comp_dev(dev);
 976
 977         return ret;
 978 }
 979
 980 static int ib_uverbs_close(struct inode *inode, struct file *filp)
 981 {
 982         struct ib_uverbs_file *file = filp->private_data;
 983         struct ib_uverbs_device *dev = file->device;
 984         struct ib_ucontext *ucontext = NULL;
 985
 986         mutex_lock(&file->device->lists_mutex);
 987         ucontext = file->ucontext;
 988         file->ucontext = NULL;
 989         if (!file->is_closed) {
 990                 list_del(&file->list);
 991                 file->is_closed = 1;
 992         }
 993         mutex_unlock(&file->device->lists_mutex);
 994         if (ucontext)
 995                 ib_uverbs_cleanup_ucontext(file, ucontext);
 996
 997         if (file->async_file)
 998                 kref_put(&file->async_file->ref, ib_uverbs_release_event_file);
 999
1000         kref_put(&file->ref, ib_uverbs_release_file);
1001         kobject_put(&dev->kobj);
1002
1003         return 0;
1004 }
1005
1006 static const struct file_operations uverbs_fops = {
1007         .owner   = THIS_MODULE,
1008         .write   = ib_uverbs_write,
1009         .open    = ib_uverbs_open,
1010         .release = ib_uverbs_close,
1011         .llseek  = no_llseek,
1012 };
1013
1014 static const struct file_operations uverbs_mmap_fops = {
1015         .owner   = THIS_MODULE,
1016         .write   = ib_uverbs_write,
1017         .mmap    = ib_uverbs_mmap,
1018         .open    = ib_uverbs_open,
1019         .release = ib_uverbs_close,
1020         .llseek  = no_llseek,
1021 };
1022
1023 static struct ib_client uverbs_client = {
1024         .name   = "uverbs",
1025         .add    = ib_uverbs_add_one,
1026         .remove = ib_uverbs_remove_one
1027 };
1028
1029 static ssize_t show_ibdev(struct device *device, struct device_attribute *attr,
1030                           char *buf)
1031 {
1032         int ret = -ENODEV;
1033         int srcu_key;
1034         struct ib_uverbs_device *dev = dev_get_drvdata(device);
1035         struct ib_device *ib_dev;
1036
1037         if (!dev)
1038                 return -ENODEV;
1039
1040         srcu_key = srcu_read_lock(&dev->disassociate_srcu);
1041         ib_dev = srcu_dereference(dev->ib_dev, &dev->disassociate_srcu);
1042         if (ib_dev)
1043                 ret = sprintf(buf, "%s\n", ib_dev->name);
1044         srcu_read_unlock(&dev->disassociate_srcu, srcu_key);
1045
1046         return ret;
1047 }
1048 static DEVICE_ATTR(ibdev, S_IRUGO, show_ibdev, NULL);
1049
1050 static ssize_t show_dev_abi_version(struct device *device,
1051                                     struct device_attribute *attr, char *buf)
1052 {
1053         struct ib_uverbs_device *dev = dev_get_drvdata(device);
1054         int ret = -ENODEV;
1055         int srcu_key;
1056         struct ib_device *ib_dev;
1057
1058         if (!dev)
1059                 return -ENODEV;
1060         srcu_key = srcu_read_lock(&dev->disassociate_srcu);
1061         ib_dev = srcu_dereference(dev->ib_dev, &dev->disassociate_srcu);
1062         if (ib_dev)
1063                 ret = sprintf(buf, "%d\n", ib_dev->uverbs_abi_ver);
1064         srcu_read_unlock(&dev->disassociate_srcu, srcu_key);
1065
1066         return ret;
1067 }
1068 static DEVICE_ATTR(abi_version, S_IRUGO, show_dev_abi_version, NULL);
1069
1070 static CLASS_ATTR_STRING(abi_version, S_IRUGO,
1071                          __stringify(IB_USER_VERBS_ABI_VERSION));
1072
1073 static dev_t overflow_maj;
1074 static DECLARE_BITMAP(overflow_map, IB_UVERBS_MAX_DEVICES);
1075
1076 /*
1077  * If we have more than IB_UVERBS_MAX_DEVICES, dynamically overflow by
1078  * requesting a new major number and doubling the number of max devices we
1079  * support. It's stupid, but simple.
1080  */
1081 static int find_overflow_devnum(void)
1082 {
1083         int ret;
1084
1085         if (!overflow_maj) {
1086                 ret = alloc_chrdev_region(&overflow_maj, 0, IB_UVERBS_MAX_DEVICES,
1087                                           "infiniband_verbs");
1088                 if (ret) {
1089                         pr_err("user_verbs: couldn't register dynamic device number\n");
1090                         return ret;
1091                 }
1092         }
1093
1094         ret = find_first_zero_bit(overflow_map, IB_UVERBS_MAX_DEVICES);
1095         if (ret >= IB_UVERBS_MAX_DEVICES)
1096                 return -1;
1097
1098         return ret;
1099 }
1100
1101 static void ib_uverbs_add_one(struct ib_device *device)
1102 {
1103         int devnum;
1104         dev_t base;
1105         struct ib_uverbs_device *uverbs_dev;
1106         int ret;
1107
1108         if (!device->alloc_ucontext)
1109                 return;
1110
1111         uverbs_dev = kzalloc(sizeof *uverbs_dev, GFP_KERNEL);
1112         if (!uverbs_dev)
1113                 return;
1114
1115         ret = init_srcu_struct(&uverbs_dev->disassociate_srcu);
1116         if (ret) {
1117                 kfree(uverbs_dev);
1118                 return;
1119         }
1120
1121         atomic_set(&uverbs_dev->refcount, 1);
1122         init_completion(&uverbs_dev->comp);
1123         uverbs_dev->xrcd_tree = RB_ROOT;
1124         mutex_init(&uverbs_dev->xrcd_tree_mutex);
1125         kobject_init(&uverbs_dev->kobj, &ib_uverbs_dev_ktype);
1126         mutex_init(&uverbs_dev->lists_mutex);
1127         INIT_LIST_HEAD(&uverbs_dev->uverbs_file_list);
1128         INIT_LIST_HEAD(&uverbs_dev->uverbs_events_file_list);
1129
1130         spin_lock(&map_lock);
1131         devnum = find_first_zero_bit(dev_map, IB_UVERBS_MAX_DEVICES);
1132         if (devnum >= IB_UVERBS_MAX_DEVICES) {
1133                 spin_unlock(&map_lock);
1134                 devnum = find_overflow_devnum();
1135                 if (devnum < 0)
1136                         goto err;
1137
1138                 spin_lock(&map_lock);
1139                 uverbs_dev->devnum = devnum + IB_UVERBS_MAX_DEVICES;
1140                 base = devnum + overflow_maj;
1141                 set_bit(devnum, overflow_map);
1142         } else {
1143                 uverbs_dev->devnum = devnum;
1144                 base = devnum + IB_UVERBS_BASE_DEV;
1145                 set_bit(devnum, dev_map);
1146         }
1147         spin_unlock(&map_lock);
1148
1149         rcu_assign_pointer(uverbs_dev->ib_dev, device);
1150         uverbs_dev->num_comp_vectors = device->num_comp_vectors;
1151
1152         cdev_init(&uverbs_dev->cdev, NULL);
1153         uverbs_dev->cdev.owner = THIS_MODULE;
1154         uverbs_dev->cdev.ops = device->mmap ? &uverbs_mmap_fops : &uverbs_fops;
1155         uverbs_dev->cdev.kobj.parent = &uverbs_dev->kobj;
1156         kobject_set_name(&uverbs_dev->cdev.kobj, "uverbs%d", uverbs_dev->devnum);
1157         if (cdev_add(&uverbs_dev->cdev, base, 1))
1158                 goto err_cdev;
1159
1160         uverbs_dev->dev = device_create(uverbs_class, device->dma_device,
1161                                         uverbs_dev->cdev.dev, uverbs_dev,
1162                                         "uverbs%d", uverbs_dev->devnum);
1163         if (IS_ERR(uverbs_dev->dev))
1164                 goto err_cdev;
1165
1166         if (device_create_file(uverbs_dev->dev, &dev_attr_ibdev))
1167                 goto err_class;
1168         if (device_create_file(uverbs_dev->dev, &dev_attr_abi_version))
1169                 goto err_class;
1170
1171         ib_set_client_data(device, &uverbs_client, uverbs_dev);
1172
1173         return;
1174
1175 err_class:
1176         device_destroy(uverbs_class, uverbs_dev->cdev.dev);
1177
1178 err_cdev:
1179         cdev_del(&uverbs_dev->cdev);
1180         if (uverbs_dev->devnum < IB_UVERBS_MAX_DEVICES)
1181                 clear_bit(devnum, dev_map);
1182         else
1183                 clear_bit(devnum, overflow_map);
1184
1185 err:
1186         if (atomic_dec_and_test(&uverbs_dev->refcount))
1187                 ib_uverbs_comp_dev(uverbs_dev);
1188         wait_for_completion(&uverbs_dev->comp);
1189         kobject_put(&uverbs_dev->kobj);
1190         return;
1191 }
1192
1193 static void ib_uverbs_free_hw_resources(struct ib_uverbs_device *uverbs_dev,
1194                                         struct ib_device *ib_dev)
1195 {
1196         struct ib_uverbs_file *file;
1197         struct ib_uverbs_event_file *event_file;
1198         struct ib_event event;
1199
1200         /* Pending running commands to terminate */
1201         synchronize_srcu(&uverbs_dev->disassociate_srcu);
1202         event.event = IB_EVENT_DEVICE_FATAL;
1203         event.element.port_num = 0;
1204         event.device = ib_dev;
1205
1206         mutex_lock(&uverbs_dev->lists_mutex);
1207         while (!list_empty(&uverbs_dev->uverbs_file_list)) {
1208                 struct ib_ucontext *ucontext;
1209
1210                 file = list_first_entry(&uverbs_dev->uverbs_file_list,
1211                                         struct ib_uverbs_file, list);
1212                 file->is_closed = 1;
1213                 ucontext = file->ucontext;
1214                 list_del(&file->list);
1215                 file->ucontext = NULL;
1216                 kref_get(&file->ref);
1217                 mutex_unlock(&uverbs_dev->lists_mutex);
1218                 /* We must release the mutex before going ahead and calling
1219                  * disassociate_ucontext. disassociate_ucontext might end up
1220                  * indirectly calling uverbs_close, for example due to freeing
1221                  * the resources (e.g mmput).
1222                  */
1223                 ib_uverbs_event_handler(&file->event_handler, &event);
1224                 if (ucontext) {
1225                         ib_dev->disassociate_ucontext(ucontext);
1226                         ib_uverbs_cleanup_ucontext(file, ucontext);
1227                 }
1228
1229                 mutex_lock(&uverbs_dev->lists_mutex);
1230                 kref_put(&file->ref, ib_uverbs_release_file);
1231         }
1232
1233         while (!list_empty(&uverbs_dev->uverbs_events_file_list)) {
1234                 event_file = list_first_entry(&uverbs_dev->
1235                                               uverbs_events_file_list,
1236                                               struct ib_uverbs_event_file,
1237                                               list);
1238                 spin_lock_irq(&event_file->lock);
1239                 event_file->is_closed = 1;
1240                 spin_unlock_irq(&event_file->lock);
1241
1242                 list_del(&event_file->list);
1243                 if (event_file->is_async) {
1244                         ib_unregister_event_handler(&event_file->uverbs_file->
1245                                                     event_handler);
1246                         event_file->uverbs_file->event_handler.device = NULL;
1247                 }
1248
1249                 wake_up_interruptible(&event_file->poll_wait);
1250                 kill_fasync(&event_file->async_queue, SIGIO, POLL_IN);
1251         }
1252         mutex_unlock(&uverbs_dev->lists_mutex);
1253 }
1254
1255 static void ib_uverbs_remove_one(struct ib_device *device, void *client_data)
1256 {
1257         struct ib_uverbs_device *uverbs_dev = client_data;
1258         int wait_clients = 1;
1259
1260         if (!uverbs_dev)
1261                 return;
1262
1263         dev_set_drvdata(uverbs_dev->dev, NULL);
1264         device_destroy(uverbs_class, uverbs_dev->cdev.dev);
1265         cdev_del(&uverbs_dev->cdev);
1266
1267         if (uverbs_dev->devnum < IB_UVERBS_MAX_DEVICES)
1268                 clear_bit(uverbs_dev->devnum, dev_map);
1269         else
1270                 clear_bit(uverbs_dev->devnum - IB_UVERBS_MAX_DEVICES, overflow_map);
1271
1272         if (device->disassociate_ucontext) {
1273                 /* We disassociate HW resources and immediately return.
1274                  * Userspace will see a EIO errno for all future access.
1275                  * Upon returning, ib_device may be freed internally and is not
1276                  * valid any more.
1277                  * uverbs_device is still available until all clients close
1278                  * their files, then the uverbs device ref count will be zero
1279                  * and its resources will be freed.
1280                  * Note: At this point no more files can be opened since the
1281                  * cdev was deleted, however active clients can still issue
1282                  * commands and close their open files.
1283                  */
1284                 rcu_assign_pointer(uverbs_dev->ib_dev, NULL);
1285                 ib_uverbs_free_hw_resources(uverbs_dev, device);
1286                 wait_clients = 0;
1287         }
1288
1289         if (atomic_dec_and_test(&uverbs_dev->refcount))
1290                 ib_uverbs_comp_dev(uverbs_dev);
1291         if (wait_clients)
1292                 wait_for_completion(&uverbs_dev->comp);
1293         kobject_put(&uverbs_dev->kobj);
1294 }
1295
1296 static char *uverbs_devnode(struct device *dev, umode_t *mode)
1297 {
1298         if (mode)
1299                 *mode = 0666;
1300         return kasprintf(GFP_KERNEL, "infiniband/%s", dev_name(dev));
1301 }
1302
1303 static int __init ib_uverbs_init(void)
1304 {
1305         int ret;
1306
1307         ret = register_chrdev_region(IB_UVERBS_BASE_DEV, IB_UVERBS_MAX_DEVICES,
1308                                      "infiniband_verbs");
1309         if (ret) {
1310                 pr_err("user_verbs: couldn't register device number\n");
1311                 goto out;
1312         }
1313
1314         uverbs_class = class_create(THIS_MODULE, "infiniband_verbs");
1315         if (IS_ERR(uverbs_class)) {
1316                 ret = PTR_ERR(uverbs_class);
1317                 pr_err("user_verbs: couldn't create class infiniband_verbs\n");
1318                 goto out_chrdev;
1319         }
1320
1321         uverbs_class->devnode = uverbs_devnode;
1322
1323         ret = class_create_file(uverbs_class, &class_attr_abi_version.attr);
1324         if (ret) {
1325                 pr_err("user_verbs: couldn't create abi_version attribute\n");
1326                 goto out_class;
1327         }
1328
1329         ret = ib_register_client(&uverbs_client);
1330         if (ret) {
1331                 pr_err("user_verbs: couldn't register client\n");
1332                 goto out_class;
1333         }
1334
1335         return 0;
1336
1337 out_class:
1338         class_destroy(uverbs_class);
1339
1340 out_chrdev:
1341         unregister_chrdev_region(IB_UVERBS_BASE_DEV, IB_UVERBS_MAX_DEVICES);
1342
1343 out:
1344         return ret;
1345 }
1346
1347 static void __exit ib_uverbs_cleanup(void)
1348 {
1349         ib_unregister_client(&uverbs_client);
1350         class_destroy(uverbs_class);
1351         unregister_chrdev_region(IB_UVERBS_BASE_DEV, IB_UVERBS_MAX_DEVICES);
1352         if (overflow_maj)
1353                 unregister_chrdev_region(overflow_maj, IB_UVERBS_MAX_DEVICES);
1354         idr_destroy(&ib_uverbs_pd_idr);
1355         idr_destroy(&ib_uverbs_mr_idr);
1356         idr_destroy(&ib_uverbs_mw_idr);
1357         idr_destroy(&ib_uverbs_ah_idr);
1358         idr_destroy(&ib_uverbs_cq_idr);
1359         idr_destroy(&ib_uverbs_qp_idr);
1360         idr_destroy(&ib_uverbs_srq_idr);
1361 }
1362
1363 module_init(ib_uverbs_init);
1364 module_exit(ib_uverbs_cleanup);