drivers/infiniband/core/uverbs_main.c

   1 /*
   2  * Copyright (c) 2005 Topspin Communications.  All rights reserved.
   3  * Copyright (c) 2005, 2006 Cisco Systems.  All rights reserved.
   4  * Copyright (c) 2005 Mellanox Technologies. All rights reserved.
   5  * Copyright (c) 2005 Voltaire, Inc. All rights reserved.
   6  * Copyright (c) 2005 PathScale, Inc. All rights reserved.
   7  *
   8  * This software is available to you under a choice of one of two
   9  * licenses.  You may choose to be licensed under the terms of the GNU
  10  * General Public License (GPL) Version 2, available from the file
  11  * COPYING in the main directory of this source tree, or the
  12  * OpenIB.org BSD license below:
  13  *
  14  *     Redistribution and use in source and binary forms, with or
  15  *     without modification, are permitted provided that the following
  16  *     conditions are met:
  17  *
  18  *      - Redistributions of source code must retain the above
  19  *        copyright notice, this list of conditions and the following
  20  *        disclaimer.
  21  *
  22  *      - Redistributions in binary form must reproduce the above
  23  *        copyright notice, this list of conditions and the following
  24  *        disclaimer in the documentation and/or other materials
  25  *        provided with the distribution.
  26  *
  27  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  28  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  29  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  30  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  31  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  32  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  33  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  34  * SOFTWARE.
  35  */
  36
  37 #include <linux/module.h>
  38 #include <linux/init.h>
  39 #include <linux/device.h>
  40 #include <linux/err.h>
  41 #include <linux/fs.h>
  42 #include <linux/poll.h>
  43 #include <linux/sched.h>
  44 #include <linux/file.h>
  45 #include <linux/cdev.h>
  46 #include <linux/anon_inodes.h>
  47 #include <linux/slab.h>
  48
  49 #include <linux/uaccess.h>
  50
  51 #include <rdma/ib.h>
  52
  53 #include "uverbs.h"
  54 #include "core_priv.h"
  55 #include "rdma_core.h"
  56
  57 MODULE_AUTHOR("Roland Dreier");
  58 MODULE_DESCRIPTION("InfiniBand userspace verbs access");
  59 MODULE_LICENSE("Dual BSD/GPL");
  60
  61 enum {
  62         IB_UVERBS_MAJOR       = 231,
  63         IB_UVERBS_BASE_MINOR  = 192,
  64         IB_UVERBS_MAX_DEVICES = 32
  65 };
  66
  67 #define IB_UVERBS_BASE_DEV      MKDEV(IB_UVERBS_MAJOR, IB_UVERBS_BASE_MINOR)
  68
  69 static struct class *uverbs_class;
  70
  71 static DEFINE_SPINLOCK(map_lock);
  72 static DECLARE_BITMAP(dev_map, IB_UVERBS_MAX_DEVICES);
  73
  74 static ssize_t (*uverbs_cmd_table[])(struct ib_uverbs_file *file,
  75                                      struct ib_device *ib_dev,
  76                                      const char __user *buf, int in_len,
  77                                      int out_len) = {
  78         [IB_USER_VERBS_CMD_GET_CONTEXT]         = ib_uverbs_get_context,
  79         [IB_USER_VERBS_CMD_QUERY_DEVICE]        = ib_uverbs_query_device,
  80         [IB_USER_VERBS_CMD_QUERY_PORT]          = ib_uverbs_query_port,
  81         [IB_USER_VERBS_CMD_ALLOC_PD]            = ib_uverbs_alloc_pd,
  82         [IB_USER_VERBS_CMD_DEALLOC_PD]          = ib_uverbs_dealloc_pd,
  83         [IB_USER_VERBS_CMD_REG_MR]              = ib_uverbs_reg_mr,
  84         [IB_USER_VERBS_CMD_REREG_MR]            = ib_uverbs_rereg_mr,
  85         [IB_USER_VERBS_CMD_DEREG_MR]            = ib_uverbs_dereg_mr,
  86         [IB_USER_VERBS_CMD_ALLOC_MW]            = ib_uverbs_alloc_mw,
  87         [IB_USER_VERBS_CMD_DEALLOC_MW]          = ib_uverbs_dealloc_mw,
  88         [IB_USER_VERBS_CMD_CREATE_COMP_CHANNEL] = ib_uverbs_create_comp_channel,
  89         [IB_USER_VERBS_CMD_CREATE_CQ]           = ib_uverbs_create_cq,
  90         [IB_USER_VERBS_CMD_RESIZE_CQ]           = ib_uverbs_resize_cq,
  91         [IB_USER_VERBS_CMD_POLL_CQ]             = ib_uverbs_poll_cq,
  92         [IB_USER_VERBS_CMD_REQ_NOTIFY_CQ]       = ib_uverbs_req_notify_cq,
  93         [IB_USER_VERBS_CMD_DESTROY_CQ]          = ib_uverbs_destroy_cq,
  94         [IB_USER_VERBS_CMD_CREATE_QP]           = ib_uverbs_create_qp,
  95         [IB_USER_VERBS_CMD_QUERY_QP]            = ib_uverbs_query_qp,
  96         [IB_USER_VERBS_CMD_MODIFY_QP]           = ib_uverbs_modify_qp,
  97         [IB_USER_VERBS_CMD_DESTROY_QP]          = ib_uverbs_destroy_qp,
  98         [IB_USER_VERBS_CMD_POST_SEND]           = ib_uverbs_post_send,
  99         [IB_USER_VERBS_CMD_POST_RECV]           = ib_uverbs_post_recv,
 100         [IB_USER_VERBS_CMD_POST_SRQ_RECV]       = ib_uverbs_post_srq_recv,
 101         [IB_USER_VERBS_CMD_CREATE_AH]           = ib_uverbs_create_ah,
 102         [IB_USER_VERBS_CMD_DESTROY_AH]          = ib_uverbs_destroy_ah,
 103         [IB_USER_VERBS_CMD_ATTACH_MCAST]        = ib_uverbs_attach_mcast,
 104         [IB_USER_VERBS_CMD_DETACH_MCAST]        = ib_uverbs_detach_mcast,
 105         [IB_USER_VERBS_CMD_CREATE_SRQ]          = ib_uverbs_create_srq,
 106         [IB_USER_VERBS_CMD_MODIFY_SRQ]          = ib_uverbs_modify_srq,
 107         [IB_USER_VERBS_CMD_QUERY_SRQ]           = ib_uverbs_query_srq,
 108         [IB_USER_VERBS_CMD_DESTROY_SRQ]         = ib_uverbs_destroy_srq,
 109         [IB_USER_VERBS_CMD_OPEN_XRCD]           = ib_uverbs_open_xrcd,
 110         [IB_USER_VERBS_CMD_CLOSE_XRCD]          = ib_uverbs_close_xrcd,
 111         [IB_USER_VERBS_CMD_CREATE_XSRQ]         = ib_uverbs_create_xsrq,
 112         [IB_USER_VERBS_CMD_OPEN_QP]             = ib_uverbs_open_qp,
 113 };
 114
 115 static int (*uverbs_ex_cmd_table[])(struct ib_uverbs_file *file,
 116                                     struct ib_device *ib_dev,
 117                                     struct ib_udata *ucore,
 118                                     struct ib_udata *uhw) = {
 119         [IB_USER_VERBS_EX_CMD_CREATE_FLOW]      = ib_uverbs_ex_create_flow,
 120         [IB_USER_VERBS_EX_CMD_DESTROY_FLOW]     = ib_uverbs_ex_destroy_flow,
 121         [IB_USER_VERBS_EX_CMD_QUERY_DEVICE]     = ib_uverbs_ex_query_device,
 122         [IB_USER_VERBS_EX_CMD_CREATE_CQ]        = ib_uverbs_ex_create_cq,
 123         [IB_USER_VERBS_EX_CMD_CREATE_QP]        = ib_uverbs_ex_create_qp,
 124         [IB_USER_VERBS_EX_CMD_CREATE_WQ]        = ib_uverbs_ex_create_wq,
 125         [IB_USER_VERBS_EX_CMD_MODIFY_WQ]        = ib_uverbs_ex_modify_wq,
 126         [IB_USER_VERBS_EX_CMD_DESTROY_WQ]       = ib_uverbs_ex_destroy_wq,
 127         [IB_USER_VERBS_EX_CMD_CREATE_RWQ_IND_TBL] = ib_uverbs_ex_create_rwq_ind_table,
 128         [IB_USER_VERBS_EX_CMD_DESTROY_RWQ_IND_TBL] = ib_uverbs_ex_destroy_rwq_ind_table,
 129         [IB_USER_VERBS_EX_CMD_MODIFY_QP]        = ib_uverbs_ex_modify_qp,
 130 };
 131
 132 static void ib_uverbs_add_one(struct ib_device *device);
 133 static void ib_uverbs_remove_one(struct ib_device *device, void *client_data);
 134
 135 int uverbs_dealloc_mw(struct ib_mw *mw)
 136 {
 137         struct ib_pd *pd = mw->pd;
 138         int ret;
 139
 140         ret = mw->device->dealloc_mw(mw);
 141         if (!ret)
 142                 atomic_dec(&pd->usecnt);
 143         return ret;
 144 }
 145
 146 static void ib_uverbs_release_dev(struct kobject *kobj)
 147 {
 148         struct ib_uverbs_device *dev =
 149                 container_of(kobj, struct ib_uverbs_device, kobj);
 150
 151         cleanup_srcu_struct(&dev->disassociate_srcu);
 152         kfree(dev);
 153 }
 154
 155 static struct kobj_type ib_uverbs_dev_ktype = {
 156         .release = ib_uverbs_release_dev,
 157 };
 158
 159 static void ib_uverbs_release_async_event_file(struct kref *ref)
 160 {
 161         struct ib_uverbs_async_event_file *file =
 162                 container_of(ref, struct ib_uverbs_async_event_file, ref);
 163
 164         kfree(file);
 165 }
 166
 167 void ib_uverbs_release_ucq(struct ib_uverbs_file *file,
 168                           struct ib_uverbs_completion_event_file *ev_file,
 169                           struct ib_ucq_object *uobj)
 170 {
 171         struct ib_uverbs_event *evt, *tmp;
 172
 173         if (ev_file) {
 174                 spin_lock_irq(&ev_file->ev_queue.lock);
 175                 list_for_each_entry_safe(evt, tmp, &uobj->comp_list, obj_list) {
 176                         list_del(&evt->list);
 177                         kfree(evt);
 178                 }
 179                 spin_unlock_irq(&ev_file->ev_queue.lock);
 180
 181                 uverbs_uobject_put(&ev_file->uobj_file.uobj);
 182         }
 183
 184         spin_lock_irq(&file->async_file->ev_queue.lock);
 185         list_for_each_entry_safe(evt, tmp, &uobj->async_list, obj_list) {
 186                 list_del(&evt->list);
 187                 kfree(evt);
 188         }
 189         spin_unlock_irq(&file->async_file->ev_queue.lock);
 190 }
 191
 192 void ib_uverbs_release_uevent(struct ib_uverbs_file *file,
 193                               struct ib_uevent_object *uobj)
 194 {
 195         struct ib_uverbs_event *evt, *tmp;
 196
 197         spin_lock_irq(&file->async_file->ev_queue.lock);
 198         list_for_each_entry_safe(evt, tmp, &uobj->event_list, obj_list) {
 199                 list_del(&evt->list);
 200                 kfree(evt);
 201         }
 202         spin_unlock_irq(&file->async_file->ev_queue.lock);
 203 }
 204
 205 void ib_uverbs_detach_umcast(struct ib_qp *qp,
 206                              struct ib_uqp_object *uobj)
 207 {
 208         struct ib_uverbs_mcast_entry *mcast, *tmp;
 209
 210         list_for_each_entry_safe(mcast, tmp, &uobj->mcast_list, list) {
 211                 ib_detach_mcast(qp, &mcast->gid, mcast->lid);
 212                 list_del(&mcast->list);
 213                 kfree(mcast);
 214         }
 215 }
 216
 217 static int ib_uverbs_cleanup_ucontext(struct ib_uverbs_file *file,
 218                                       struct ib_ucontext *context,
 219                                       bool device_removed)
 220 {
 221         context->closing = 1;
 222         uverbs_cleanup_ucontext(context, device_removed);
 223         put_pid(context->tgid);
 224
 225         ib_rdmacg_uncharge(&context->cg_obj, context->device,
 226                            RDMACG_RESOURCE_HCA_HANDLE);
 227
 228         return context->device->dealloc_ucontext(context);
 229 }
 230
 231 static void ib_uverbs_comp_dev(struct ib_uverbs_device *dev)
 232 {
 233         complete(&dev->comp);
 234 }
 235
 236 void ib_uverbs_release_file(struct kref *ref)
 237 {
 238         struct ib_uverbs_file *file =
 239                 container_of(ref, struct ib_uverbs_file, ref);
 240         struct ib_device *ib_dev;
 241         int srcu_key;
 242
 243         srcu_key = srcu_read_lock(&file->device->disassociate_srcu);
 244         ib_dev = srcu_dereference(file->device->ib_dev,
 245                                   &file->device->disassociate_srcu);
 246         if (ib_dev && !ib_dev->disassociate_ucontext)
 247                 module_put(ib_dev->owner);
 248         srcu_read_unlock(&file->device->disassociate_srcu, srcu_key);
 249
 250         if (atomic_dec_and_test(&file->device->refcount))
 251                 ib_uverbs_comp_dev(file->device);
 252
 253         kobject_put(&file->device->kobj);
 254         kfree(file);
 255 }
 256
 257 static ssize_t ib_uverbs_event_read(struct ib_uverbs_event_queue *ev_queue,
 258                                     struct ib_uverbs_file *uverbs_file,
 259                                     struct file *filp, char __user *buf,
 260                                     size_t count, loff_t *pos,
 261                                     size_t eventsz)
 262 {
 263         struct ib_uverbs_event *event;
 264         int ret = 0;
 265
 266         spin_lock_irq(&ev_queue->lock);
 267
 268         while (list_empty(&ev_queue->event_list)) {
 269                 spin_unlock_irq(&ev_queue->lock);
 270
 271                 if (filp->f_flags & O_NONBLOCK)
 272                         return -EAGAIN;
 273
 274                 if (wait_event_interruptible(ev_queue->poll_wait,
 275                                              (!list_empty(&ev_queue->event_list) ||
 276                         /* The barriers built into wait_event_interruptible()
 277                          * and wake_up() guarentee this will see the null set
 278                          * without using RCU
 279                          */
 280                                              !uverbs_file->device->ib_dev)))
 281                         return -ERESTARTSYS;
 282
 283                 /* If device was disassociated and no event exists set an error */
 284                 if (list_empty(&ev_queue->event_list) &&
 285                     !uverbs_file->device->ib_dev)
 286                         return -EIO;
 287
 288                 spin_lock_irq(&ev_queue->lock);
 289         }
 290
 291         event = list_entry(ev_queue->event_list.next, struct ib_uverbs_event, list);
 292
 293         if (eventsz > count) {
 294                 ret   = -EINVAL;
 295                 event = NULL;
 296         } else {
 297                 list_del(ev_queue->event_list.next);
 298                 if (event->counter) {
 299                         ++(*event->counter);
 300                         list_del(&event->obj_list);
 301                 }
 302         }
 303
 304         spin_unlock_irq(&ev_queue->lock);
 305
 306         if (event) {
 307                 if (copy_to_user(buf, event, eventsz))
 308                         ret = -EFAULT;
 309                 else
 310                         ret = eventsz;
 311         }
 312
 313         kfree(event);
 314
 315         return ret;
 316 }
 317
 318 static ssize_t ib_uverbs_async_event_read(struct file *filp, char __user *buf,
 319                                           size_t count, loff_t *pos)
 320 {
 321         struct ib_uverbs_async_event_file *file = filp->private_data;
 322
 323         return ib_uverbs_event_read(&file->ev_queue, file->uverbs_file, filp,
 324                                     buf, count, pos,
 325                                     sizeof(struct ib_uverbs_async_event_desc));
 326 }
 327
 328 static ssize_t ib_uverbs_comp_event_read(struct file *filp, char __user *buf,
 329                                          size_t count, loff_t *pos)
 330 {
 331         struct ib_uverbs_completion_event_file *comp_ev_file =
 332                 filp->private_data;
 333
 334         return ib_uverbs_event_read(&comp_ev_file->ev_queue,
 335                                     comp_ev_file->uobj_file.ufile, filp,
 336                                     buf, count, pos,
 337                                     sizeof(struct ib_uverbs_comp_event_desc));
 338 }
 339
 340 static unsigned int ib_uverbs_event_poll(struct ib_uverbs_event_queue *ev_queue,
 341                                          struct file *filp,
 342                                          struct poll_table_struct *wait)
 343 {
 344         unsigned int pollflags = 0;
 345
 346         poll_wait(filp, &ev_queue->poll_wait, wait);
 347
 348         spin_lock_irq(&ev_queue->lock);
 349         if (!list_empty(&ev_queue->event_list))
 350                 pollflags = POLLIN | POLLRDNORM;
 351         spin_unlock_irq(&ev_queue->lock);
 352
 353         return pollflags;
 354 }
 355
 356 static unsigned int ib_uverbs_async_event_poll(struct file *filp,
 357                                                struct poll_table_struct *wait)
 358 {
 359         return ib_uverbs_event_poll(filp->private_data, filp, wait);
 360 }
 361
 362 static unsigned int ib_uverbs_comp_event_poll(struct file *filp,
 363                                               struct poll_table_struct *wait)
 364 {
 365         struct ib_uverbs_completion_event_file *comp_ev_file =
 366                 filp->private_data;
 367
 368         return ib_uverbs_event_poll(&comp_ev_file->ev_queue, filp, wait);
 369 }
 370
 371 static int ib_uverbs_async_event_fasync(int fd, struct file *filp, int on)
 372 {
 373         struct ib_uverbs_event_queue *ev_queue = filp->private_data;
 374
 375         return fasync_helper(fd, filp, on, &ev_queue->async_queue);
 376 }
 377
 378 static int ib_uverbs_comp_event_fasync(int fd, struct file *filp, int on)
 379 {
 380         struct ib_uverbs_completion_event_file *comp_ev_file =
 381                 filp->private_data;
 382
 383         return fasync_helper(fd, filp, on, &comp_ev_file->ev_queue.async_queue);
 384 }
 385
 386 static int ib_uverbs_async_event_close(struct inode *inode, struct file *filp)
 387 {
 388         struct ib_uverbs_async_event_file *file = filp->private_data;
 389         struct ib_uverbs_file *uverbs_file = file->uverbs_file;
 390         struct ib_uverbs_event *entry, *tmp;
 391         int closed_already = 0;
 392
 393         mutex_lock(&uverbs_file->device->lists_mutex);
 394         spin_lock_irq(&file->ev_queue.lock);
 395         closed_already = file->ev_queue.is_closed;
 396         file->ev_queue.is_closed = 1;
 397         list_for_each_entry_safe(entry, tmp, &file->ev_queue.event_list, list) {
 398                 if (entry->counter)
 399                         list_del(&entry->obj_list);
 400                 kfree(entry);
 401         }
 402         spin_unlock_irq(&file->ev_queue.lock);
 403         if (!closed_already) {
 404                 list_del(&file->list);
 405                 ib_unregister_event_handler(&uverbs_file->event_handler);
 406         }
 407         mutex_unlock(&uverbs_file->device->lists_mutex);
 408
 409         kref_put(&uverbs_file->ref, ib_uverbs_release_file);
 410         kref_put(&file->ref, ib_uverbs_release_async_event_file);
 411
 412         return 0;
 413 }
 414
 415 static int ib_uverbs_comp_event_close(struct inode *inode, struct file *filp)
 416 {
 417         struct ib_uverbs_completion_event_file *file = filp->private_data;
 418         struct ib_uverbs_event *entry, *tmp;
 419
 420         spin_lock_irq(&file->ev_queue.lock);
 421         list_for_each_entry_safe(entry, tmp, &file->ev_queue.event_list, list) {
 422                 if (entry->counter)
 423                         list_del(&entry->obj_list);
 424                 kfree(entry);
 425         }
 426         spin_unlock_irq(&file->ev_queue.lock);
 427
 428         uverbs_close_fd(filp);
 429
 430         return 0;
 431 }
 432
 433 const struct file_operations uverbs_event_fops = {
 434         .owner   = THIS_MODULE,
 435         .read    = ib_uverbs_comp_event_read,
 436         .poll    = ib_uverbs_comp_event_poll,
 437         .release = ib_uverbs_comp_event_close,
 438         .fasync  = ib_uverbs_comp_event_fasync,
 439         .llseek  = no_llseek,
 440 };
 441
 442 static const struct file_operations uverbs_async_event_fops = {
 443         .owner   = THIS_MODULE,
 444         .read    = ib_uverbs_async_event_read,
 445         .poll    = ib_uverbs_async_event_poll,
 446         .release = ib_uverbs_async_event_close,
 447         .fasync  = ib_uverbs_async_event_fasync,
 448         .llseek  = no_llseek,
 449 };
 450
 451 void ib_uverbs_comp_handler(struct ib_cq *cq, void *cq_context)
 452 {
 453         struct ib_uverbs_event_queue   *ev_queue = cq_context;
 454         struct ib_ucq_object           *uobj;
 455         struct ib_uverbs_event         *entry;
 456         unsigned long                   flags;
 457
 458         if (!ev_queue)
 459                 return;
 460
 461         spin_lock_irqsave(&ev_queue->lock, flags);
 462         if (ev_queue->is_closed) {
 463                 spin_unlock_irqrestore(&ev_queue->lock, flags);
 464                 return;
 465         }
 466
 467         entry = kmalloc(sizeof *entry, GFP_ATOMIC);
 468         if (!entry) {
 469                 spin_unlock_irqrestore(&ev_queue->lock, flags);
 470                 return;
 471         }
 472
 473         uobj = container_of(cq->uobject, struct ib_ucq_object, uobject);
 474
 475         entry->desc.comp.cq_handle = cq->uobject->user_handle;
 476         entry->counter             = &uobj->comp_events_reported;
 477
 478         list_add_tail(&entry->list, &ev_queue->event_list);
 479         list_add_tail(&entry->obj_list, &uobj->comp_list);
 480         spin_unlock_irqrestore(&ev_queue->lock, flags);
 481
 482         wake_up_interruptible(&ev_queue->poll_wait);
 483         kill_fasync(&ev_queue->async_queue, SIGIO, POLL_IN);
 484 }
 485
 486 static void ib_uverbs_async_handler(struct ib_uverbs_file *file,
 487                                     __u64 element, __u64 event,
 488                                     struct list_head *obj_list,
 489                                     u32 *counter)
 490 {
 491         struct ib_uverbs_event *entry;
 492         unsigned long flags;
 493
 494         spin_lock_irqsave(&file->async_file->ev_queue.lock, flags);
 495         if (file->async_file->ev_queue.is_closed) {
 496                 spin_unlock_irqrestore(&file->async_file->ev_queue.lock, flags);
 497                 return;
 498         }
 499
 500         entry = kmalloc(sizeof *entry, GFP_ATOMIC);
 501         if (!entry) {
 502                 spin_unlock_irqrestore(&file->async_file->ev_queue.lock, flags);
 503                 return;
 504         }
 505
 506         entry->desc.async.element    = element;
 507         entry->desc.async.event_type = event;
 508         entry->desc.async.reserved   = 0;
 509         entry->counter               = counter;
 510
 511         list_add_tail(&entry->list, &file->async_file->ev_queue.event_list);
 512         if (obj_list)
 513                 list_add_tail(&entry->obj_list, obj_list);
 514         spin_unlock_irqrestore(&file->async_file->ev_queue.lock, flags);
 515
 516         wake_up_interruptible(&file->async_file->ev_queue.poll_wait);
 517         kill_fasync(&file->async_file->ev_queue.async_queue, SIGIO, POLL_IN);
 518 }
 519
 520 void ib_uverbs_cq_event_handler(struct ib_event *event, void *context_ptr)
 521 {
 522         struct ib_ucq_object *uobj = container_of(event->element.cq->uobject,
 523                                                   struct ib_ucq_object, uobject);
 524
 525         ib_uverbs_async_handler(uobj->uverbs_file, uobj->uobject.user_handle,
 526                                 event->event, &uobj->async_list,
 527                                 &uobj->async_events_reported);
 528 }
 529
 530 void ib_uverbs_qp_event_handler(struct ib_event *event, void *context_ptr)
 531 {
 532         struct ib_uevent_object *uobj;
 533
 534         /* for XRC target qp's, check that qp is live */
 535         if (!event->element.qp->uobject)
 536                 return;
 537
 538         uobj = container_of(event->element.qp->uobject,
 539                             struct ib_uevent_object, uobject);
 540
 541         ib_uverbs_async_handler(context_ptr, uobj->uobject.user_handle,
 542                                 event->event, &uobj->event_list,
 543                                 &uobj->events_reported);
 544 }
 545
 546 void ib_uverbs_wq_event_handler(struct ib_event *event, void *context_ptr)
 547 {
 548         struct ib_uevent_object *uobj = container_of(event->element.wq->uobject,
 549                                                   struct ib_uevent_object, uobject);
 550
 551         ib_uverbs_async_handler(context_ptr, uobj->uobject.user_handle,
 552                                 event->event, &uobj->event_list,
 553                                 &uobj->events_reported);
 554 }
 555
 556 void ib_uverbs_srq_event_handler(struct ib_event *event, void *context_ptr)
 557 {
 558         struct ib_uevent_object *uobj;
 559
 560         uobj = container_of(event->element.srq->uobject,
 561                             struct ib_uevent_object, uobject);
 562
 563         ib_uverbs_async_handler(context_ptr, uobj->uobject.user_handle,
 564                                 event->event, &uobj->event_list,
 565                                 &uobj->events_reported);
 566 }
 567
 568 void ib_uverbs_event_handler(struct ib_event_handler *handler,
 569                              struct ib_event *event)
 570 {
 571         struct ib_uverbs_file *file =
 572                 container_of(handler, struct ib_uverbs_file, event_handler);
 573
 574         ib_uverbs_async_handler(file, event->element.port_num, event->event,
 575                                 NULL, NULL);
 576 }
 577
 578 void ib_uverbs_free_async_event_file(struct ib_uverbs_file *file)
 579 {
 580         kref_put(&file->async_file->ref, ib_uverbs_release_async_event_file);
 581         file->async_file = NULL;
 582 }
 583
 584 void ib_uverbs_init_event_queue(struct ib_uverbs_event_queue *ev_queue)
 585 {
 586         spin_lock_init(&ev_queue->lock);
 587         INIT_LIST_HEAD(&ev_queue->event_list);
 588         init_waitqueue_head(&ev_queue->poll_wait);
 589         ev_queue->is_closed   = 0;
 590         ev_queue->async_queue = NULL;
 591 }
 592
 593 struct file *ib_uverbs_alloc_async_event_file(struct ib_uverbs_file *uverbs_file,
 594                                               struct ib_device  *ib_dev)
 595 {
 596         struct ib_uverbs_async_event_file *ev_file;
 597         struct file *filp;
 598         int ret;
 599
 600         ev_file = kzalloc(sizeof(*ev_file), GFP_KERNEL);
 601         if (!ev_file)
 602                 return ERR_PTR(-ENOMEM);
 603
 604         ib_uverbs_init_event_queue(&ev_file->ev_queue);
 605         ev_file->uverbs_file = uverbs_file;
 606         kref_get(&ev_file->uverbs_file->ref);
 607         kref_init(&ev_file->ref);
 608         filp = anon_inode_getfile("[infinibandevent]", &uverbs_async_event_fops,
 609                                   ev_file, O_RDONLY);
 610         if (IS_ERR(filp))
 611                 goto err_put_refs;
 612
 613         mutex_lock(&uverbs_file->device->lists_mutex);
 614         list_add_tail(&ev_file->list,
 615                       &uverbs_file->device->uverbs_events_file_list);
 616         mutex_unlock(&uverbs_file->device->lists_mutex);
 617
 618         WARN_ON(uverbs_file->async_file);
 619         uverbs_file->async_file = ev_file;
 620         kref_get(&uverbs_file->async_file->ref);
 621         INIT_IB_EVENT_HANDLER(&uverbs_file->event_handler,
 622                               ib_dev,
 623                               ib_uverbs_event_handler);
 624         ret = ib_register_event_handler(&uverbs_file->event_handler);
 625         if (ret)
 626                 goto err_put_file;
 627
 628         /* At that point async file stuff was fully set */
 629
 630         return filp;
 631
 632 err_put_file:
 633         fput(filp);
 634         kref_put(&uverbs_file->async_file->ref,
 635                  ib_uverbs_release_async_event_file);
 636         uverbs_file->async_file = NULL;
 637         return ERR_PTR(ret);
 638
 639 err_put_refs:
 640         kref_put(&ev_file->uverbs_file->ref, ib_uverbs_release_file);
 641         kref_put(&ev_file->ref, ib_uverbs_release_async_event_file);
 642         return filp;
 643 }
 644
 645 static int verify_command_mask(struct ib_device *ib_dev, __u32 command)
 646 {
 647         u64 mask;
 648
 649         if (command <= IB_USER_VERBS_CMD_OPEN_QP)
 650                 mask = ib_dev->uverbs_cmd_mask;
 651         else
 652                 mask = ib_dev->uverbs_ex_cmd_mask;
 653
 654         if (mask & ((u64)1 << command))
 655                 return 0;
 656
 657         return -1;
 658 }
 659
 660 static ssize_t ib_uverbs_write(struct file *filp, const char __user *buf,
 661                              size_t count, loff_t *pos)
 662 {
 663         struct ib_uverbs_file *file = filp->private_data;
 664         struct ib_device *ib_dev;
 665         struct ib_uverbs_cmd_hdr hdr;
 666         __u32 command;
 667         __u32 flags;
 668         int srcu_key;
 669         ssize_t ret;
 670
 671         if (!ib_safe_file_access(filp)) {
 672                 pr_err_once("uverbs_write: process %d (%s) changed security contexts after opening file descriptor, this is not allowed.\n",
 673                             task_tgid_vnr(current), current->comm);
 674                 return -EACCES;
 675         }
 676
 677         if (count < sizeof hdr)
 678                 return -EINVAL;
 679
 680         if (copy_from_user(&hdr, buf, sizeof hdr))
 681                 return -EFAULT;
 682
 683         srcu_key = srcu_read_lock(&file->device->disassociate_srcu);
 684         ib_dev = srcu_dereference(file->device->ib_dev,
 685                                   &file->device->disassociate_srcu);
 686         if (!ib_dev) {
 687                 ret = -EIO;
 688                 goto out;
 689         }
 690
 691         if (hdr.command & ~(__u32)(IB_USER_VERBS_CMD_FLAGS_MASK |
 692                                    IB_USER_VERBS_CMD_COMMAND_MASK)) {
 693                 ret = -EINVAL;
 694                 goto out;
 695         }
 696
 697         command = hdr.command & IB_USER_VERBS_CMD_COMMAND_MASK;
 698         if (verify_command_mask(ib_dev, command)) {
 699                 ret = -EOPNOTSUPP;
 700                 goto out;
 701         }
 702
 703         if (!file->ucontext &&
 704             command != IB_USER_VERBS_CMD_GET_CONTEXT) {
 705                 ret = -EINVAL;
 706                 goto out;
 707         }
 708
 709         flags = (hdr.command &
 710                  IB_USER_VERBS_CMD_FLAGS_MASK) >> IB_USER_VERBS_CMD_FLAGS_SHIFT;
 711
 712         if (!flags) {
 713                 if (command >= ARRAY_SIZE(uverbs_cmd_table) ||
 714                     !uverbs_cmd_table[command]) {
 715                         ret = -EINVAL;
 716                         goto out;
 717                 }
 718
 719                 if (hdr.in_words * 4 != count) {
 720                         ret = -EINVAL;
 721                         goto out;
 722                 }
 723
 724                 ret = uverbs_cmd_table[command](file, ib_dev,
 725                                                  buf + sizeof(hdr),
 726                                                  hdr.in_words * 4,
 727                                                  hdr.out_words * 4);
 728
 729         } else if (flags == IB_USER_VERBS_CMD_FLAG_EXTENDED) {
 730                 struct ib_uverbs_ex_cmd_hdr ex_hdr;
 731                 struct ib_udata ucore;
 732                 struct ib_udata uhw;
 733                 size_t written_count = count;
 734
 735                 if (command >= ARRAY_SIZE(uverbs_ex_cmd_table) ||
 736                     !uverbs_ex_cmd_table[command]) {
 737                         ret = -ENOSYS;
 738                         goto out;
 739                 }
 740
 741                 if (!file->ucontext) {
 742                         ret = -EINVAL;
 743                         goto out;
 744                 }
 745
 746                 if (count < (sizeof(hdr) + sizeof(ex_hdr))) {
 747                         ret = -EINVAL;
 748                         goto out;
 749                 }
 750
 751                 if (copy_from_user(&ex_hdr, buf + sizeof(hdr), sizeof(ex_hdr))) {
 752                         ret = -EFAULT;
 753                         goto out;
 754                 }
 755
 756                 count -= sizeof(hdr) + sizeof(ex_hdr);
 757                 buf += sizeof(hdr) + sizeof(ex_hdr);
 758
 759                 if ((hdr.in_words + ex_hdr.provider_in_words) * 8 != count) {
 760                         ret = -EINVAL;
 761                         goto out;
 762                 }
 763
 764                 if (ex_hdr.cmd_hdr_reserved) {
 765                         ret = -EINVAL;
 766                         goto out;
 767                 }
 768
 769                 if (ex_hdr.response) {
 770                         if (!hdr.out_words && !ex_hdr.provider_out_words) {
 771                                 ret = -EINVAL;
 772                                 goto out;
 773                         }
 774
 775                         if (!access_ok(VERIFY_WRITE,
 776                                        (void __user *) (unsigned long) ex_hdr.response,
 777                                        (hdr.out_words + ex_hdr.provider_out_words) * 8)) {
 778                                 ret = -EFAULT;
 779                                 goto out;
 780                         }
 781                 } else {
 782                         if (hdr.out_words || ex_hdr.provider_out_words) {
 783                                 ret = -EINVAL;
 784                                 goto out;
 785                         }
 786                 }
 787
 788                 INIT_UDATA_BUF_OR_NULL(&ucore, buf, (unsigned long) ex_hdr.response,
 789                                        hdr.in_words * 8, hdr.out_words * 8);
 790
 791                 INIT_UDATA_BUF_OR_NULL(&uhw,
 792                                        buf + ucore.inlen,
 793                                        (unsigned long) ex_hdr.response + ucore.outlen,
 794                                        ex_hdr.provider_in_words * 8,
 795                                        ex_hdr.provider_out_words * 8);
 796
 797                 ret = uverbs_ex_cmd_table[command](file,
 798                                                    ib_dev,
 799                                                    &ucore,
 800                                                    &uhw);
 801                 if (!ret)
 802                         ret = written_count;
 803         } else {
 804                 ret = -ENOSYS;
 805         }
 806
 807 out:
 808         srcu_read_unlock(&file->device->disassociate_srcu, srcu_key);
 809         return ret;
 810 }
 811
 812 static int ib_uverbs_mmap(struct file *filp, struct vm_area_struct *vma)
 813 {
 814         struct ib_uverbs_file *file = filp->private_data;
 815         struct ib_device *ib_dev;
 816         int ret = 0;
 817         int srcu_key;
 818
 819         srcu_key = srcu_read_lock(&file->device->disassociate_srcu);
 820         ib_dev = srcu_dereference(file->device->ib_dev,
 821                                   &file->device->disassociate_srcu);
 822         if (!ib_dev) {
 823                 ret = -EIO;
 824                 goto out;
 825         }
 826
 827         if (!file->ucontext)
 828                 ret = -ENODEV;
 829         else
 830                 ret = ib_dev->mmap(file->ucontext, vma);
 831 out:
 832         srcu_read_unlock(&file->device->disassociate_srcu, srcu_key);
 833         return ret;
 834 }
 835
 836 /*
 837  * ib_uverbs_open() does not need the BKL:
 838  *
 839  *  - the ib_uverbs_device structures are properly reference counted and
 840  *    everything else is purely local to the file being created, so
 841  *    races against other open calls are not a problem;
 842  *  - there is no ioctl method to race against;
 843  *  - the open method will either immediately run -ENXIO, or all
 844  *    required initialization will be done.
 845  */
 846 static int ib_uverbs_open(struct inode *inode, struct file *filp)
 847 {
 848         struct ib_uverbs_device *dev;
 849         struct ib_uverbs_file *file;
 850         struct ib_device *ib_dev;
 851         int ret;
 852         int module_dependent;
 853         int srcu_key;
 854
 855         dev = container_of(inode->i_cdev, struct ib_uverbs_device, cdev);
 856         if (!atomic_inc_not_zero(&dev->refcount))
 857                 return -ENXIO;
 858
 859         srcu_key = srcu_read_lock(&dev->disassociate_srcu);
 860         mutex_lock(&dev->lists_mutex);
 861         ib_dev = srcu_dereference(dev->ib_dev,
 862                                   &dev->disassociate_srcu);
 863         if (!ib_dev) {
 864                 ret = -EIO;
 865                 goto err;
 866         }
 867
 868         /* In case IB device supports disassociate ucontext, there is no hard
 869          * dependency between uverbs device and its low level device.
 870          */
 871         module_dependent = !(ib_dev->disassociate_ucontext);
 872
 873         if (module_dependent) {
 874                 if (!try_module_get(ib_dev->owner)) {
 875                         ret = -ENODEV;
 876                         goto err;
 877                 }
 878         }
 879
 880         file = kzalloc(sizeof(*file), GFP_KERNEL);
 881         if (!file) {
 882                 ret = -ENOMEM;
 883                 if (module_dependent)
 884                         goto err_module;
 885
 886                 goto err;
 887         }
 888
 889         file->device     = dev;
 890         spin_lock_init(&file->idr_lock);
 891         idr_init(&file->idr);
 892         file->ucontext   = NULL;
 893         file->async_file = NULL;
 894         kref_init(&file->ref);
 895         mutex_init(&file->mutex);
 896         mutex_init(&file->cleanup_mutex);
 897
 898         filp->private_data = file;
 899         kobject_get(&dev->kobj);
 900         list_add_tail(&file->list, &dev->uverbs_file_list);
 901         mutex_unlock(&dev->lists_mutex);
 902         srcu_read_unlock(&dev->disassociate_srcu, srcu_key);
 903
 904         return nonseekable_open(inode, filp);
 905
 906 err_module:
 907         module_put(ib_dev->owner);
 908
 909 err:
 910         mutex_unlock(&dev->lists_mutex);
 911         srcu_read_unlock(&dev->disassociate_srcu, srcu_key);
 912         if (atomic_dec_and_test(&dev->refcount))
 913                 ib_uverbs_comp_dev(dev);
 914
 915         return ret;
 916 }
 917
 918 static int ib_uverbs_close(struct inode *inode, struct file *filp)
 919 {
 920         struct ib_uverbs_file *file = filp->private_data;
 921
 922         mutex_lock(&file->cleanup_mutex);
 923         if (file->ucontext) {
 924                 ib_uverbs_cleanup_ucontext(file, file->ucontext, false);
 925                 file->ucontext = NULL;
 926         }
 927         mutex_unlock(&file->cleanup_mutex);
 928         idr_destroy(&file->idr);
 929
 930         mutex_lock(&file->device->lists_mutex);
 931         if (!file->is_closed) {
 932                 list_del(&file->list);
 933                 file->is_closed = 1;
 934         }
 935         mutex_unlock(&file->device->lists_mutex);
 936
 937         if (file->async_file)
 938                 kref_put(&file->async_file->ref,
 939                          ib_uverbs_release_async_event_file);
 940
 941         kref_put(&file->ref, ib_uverbs_release_file);
 942
 943         return 0;
 944 }
 945
 946 static const struct file_operations uverbs_fops = {
 947         .owner   = THIS_MODULE,
 948         .write   = ib_uverbs_write,
 949         .open    = ib_uverbs_open,
 950         .release = ib_uverbs_close,
 951         .llseek  = no_llseek,
 952 };
 953
 954 static const struct file_operations uverbs_mmap_fops = {
 955         .owner   = THIS_MODULE,
 956         .write   = ib_uverbs_write,
 957         .mmap    = ib_uverbs_mmap,
 958         .open    = ib_uverbs_open,
 959         .release = ib_uverbs_close,
 960         .llseek  = no_llseek,
 961 };
 962
 963 static struct ib_client uverbs_client = {
 964         .name   = "uverbs",
 965         .add    = ib_uverbs_add_one,
 966         .remove = ib_uverbs_remove_one
 967 };
 968
 969 static ssize_t show_ibdev(struct device *device, struct device_attribute *attr,
 970                           char *buf)
 971 {
 972         int ret = -ENODEV;
 973         int srcu_key;
 974         struct ib_uverbs_device *dev = dev_get_drvdata(device);
 975         struct ib_device *ib_dev;
 976
 977         if (!dev)
 978                 return -ENODEV;
 979
 980         srcu_key = srcu_read_lock(&dev->disassociate_srcu);
 981         ib_dev = srcu_dereference(dev->ib_dev, &dev->disassociate_srcu);
 982         if (ib_dev)
 983                 ret = sprintf(buf, "%s\n", ib_dev->name);
 984         srcu_read_unlock(&dev->disassociate_srcu, srcu_key);
 985
 986         return ret;
 987 }
 988 static DEVICE_ATTR(ibdev, S_IRUGO, show_ibdev, NULL);
 989
 990 static ssize_t show_dev_abi_version(struct device *device,
 991                                     struct device_attribute *attr, char *buf)
 992 {
 993         struct ib_uverbs_device *dev = dev_get_drvdata(device);
 994         int ret = -ENODEV;
 995         int srcu_key;
 996         struct ib_device *ib_dev;
 997
 998         if (!dev)
 999                 return -ENODEV;
1000         srcu_key = srcu_read_lock(&dev->disassociate_srcu);
1001         ib_dev = srcu_dereference(dev->ib_dev, &dev->disassociate_srcu);
1002         if (ib_dev)
1003                 ret = sprintf(buf, "%d\n", ib_dev->uverbs_abi_ver);
1004         srcu_read_unlock(&dev->disassociate_srcu, srcu_key);
1005
1006         return ret;
1007 }
1008 static DEVICE_ATTR(abi_version, S_IRUGO, show_dev_abi_version, NULL);
1009
1010 static CLASS_ATTR_STRING(abi_version, S_IRUGO,
1011                          __stringify(IB_USER_VERBS_ABI_VERSION));
1012
1013 static dev_t overflow_maj;
1014 static DECLARE_BITMAP(overflow_map, IB_UVERBS_MAX_DEVICES);
1015
1016 /*
1017  * If we have more than IB_UVERBS_MAX_DEVICES, dynamically overflow by
1018  * requesting a new major number and doubling the number of max devices we
1019  * support. It's stupid, but simple.
1020  */
1021 static int find_overflow_devnum(void)
1022 {
1023         int ret;
1024
1025         if (!overflow_maj) {
1026                 ret = alloc_chrdev_region(&overflow_maj, 0, IB_UVERBS_MAX_DEVICES,
1027                                           "infiniband_verbs");
1028                 if (ret) {
1029                         pr_err("user_verbs: couldn't register dynamic device number\n");
1030                         return ret;
1031                 }
1032         }
1033
1034         ret = find_first_zero_bit(overflow_map, IB_UVERBS_MAX_DEVICES);
1035         if (ret >= IB_UVERBS_MAX_DEVICES)
1036                 return -1;
1037
1038         return ret;
1039 }
1040
1041 static void ib_uverbs_add_one(struct ib_device *device)
1042 {
1043         int devnum;
1044         dev_t base;
1045         struct ib_uverbs_device *uverbs_dev;
1046         int ret;
1047
1048         if (!device->alloc_ucontext)
1049                 return;
1050
1051         uverbs_dev = kzalloc(sizeof *uverbs_dev, GFP_KERNEL);
1052         if (!uverbs_dev)
1053                 return;
1054
1055         ret = init_srcu_struct(&uverbs_dev->disassociate_srcu);
1056         if (ret) {
1057                 kfree(uverbs_dev);
1058                 return;
1059         }
1060
1061         atomic_set(&uverbs_dev->refcount, 1);
1062         init_completion(&uverbs_dev->comp);
1063         uverbs_dev->xrcd_tree = RB_ROOT;
1064         mutex_init(&uverbs_dev->xrcd_tree_mutex);
1065         kobject_init(&uverbs_dev->kobj, &ib_uverbs_dev_ktype);
1066         mutex_init(&uverbs_dev->lists_mutex);
1067         INIT_LIST_HEAD(&uverbs_dev->uverbs_file_list);
1068         INIT_LIST_HEAD(&uverbs_dev->uverbs_events_file_list);
1069
1070         spin_lock(&map_lock);
1071         devnum = find_first_zero_bit(dev_map, IB_UVERBS_MAX_DEVICES);
1072         if (devnum >= IB_UVERBS_MAX_DEVICES) {
1073                 spin_unlock(&map_lock);
1074                 devnum = find_overflow_devnum();
1075                 if (devnum < 0)
1076                         goto err;
1077
1078                 spin_lock(&map_lock);
1079                 uverbs_dev->devnum = devnum + IB_UVERBS_MAX_DEVICES;
1080                 base = devnum + overflow_maj;
1081                 set_bit(devnum, overflow_map);
1082         } else {
1083                 uverbs_dev->devnum = devnum;
1084                 base = devnum + IB_UVERBS_BASE_DEV;
1085                 set_bit(devnum, dev_map);
1086         }
1087         spin_unlock(&map_lock);
1088
1089         rcu_assign_pointer(uverbs_dev->ib_dev, device);
1090         uverbs_dev->num_comp_vectors = device->num_comp_vectors;
1091
1092         cdev_init(&uverbs_dev->cdev, NULL);
1093         uverbs_dev->cdev.owner = THIS_MODULE;
1094         uverbs_dev->cdev.ops = device->mmap ? &uverbs_mmap_fops : &uverbs_fops;
1095         cdev_set_parent(&uverbs_dev->cdev, &uverbs_dev->kobj);
1096         kobject_set_name(&uverbs_dev->cdev.kobj, "uverbs%d", uverbs_dev->devnum);
1097         if (cdev_add(&uverbs_dev->cdev, base, 1))
1098                 goto err_cdev;
1099
1100         uverbs_dev->dev = device_create(uverbs_class, device->dev.parent,
1101                                         uverbs_dev->cdev.dev, uverbs_dev,
1102                                         "uverbs%d", uverbs_dev->devnum);
1103         if (IS_ERR(uverbs_dev->dev))
1104                 goto err_cdev;
1105
1106         if (device_create_file(uverbs_dev->dev, &dev_attr_ibdev))
1107                 goto err_class;
1108         if (device_create_file(uverbs_dev->dev, &dev_attr_abi_version))
1109                 goto err_class;
1110
1111         ib_set_client_data(device, &uverbs_client, uverbs_dev);
1112
1113         return;
1114
1115 err_class:
1116         device_destroy(uverbs_class, uverbs_dev->cdev.dev);
1117
1118 err_cdev:
1119         cdev_del(&uverbs_dev->cdev);
1120         if (uverbs_dev->devnum < IB_UVERBS_MAX_DEVICES)
1121                 clear_bit(devnum, dev_map);
1122         else
1123                 clear_bit(devnum, overflow_map);
1124
1125 err:
1126         if (atomic_dec_and_test(&uverbs_dev->refcount))
1127                 ib_uverbs_comp_dev(uverbs_dev);
1128         wait_for_completion(&uverbs_dev->comp);
1129         kobject_put(&uverbs_dev->kobj);
1130         return;
1131 }
1132
1133 static void ib_uverbs_free_hw_resources(struct ib_uverbs_device *uverbs_dev,
1134                                         struct ib_device *ib_dev)
1135 {
1136         struct ib_uverbs_file *file;
1137         struct ib_uverbs_async_event_file *event_file;
1138         struct ib_event event;
1139
1140         /* Pending running commands to terminate */
1141         synchronize_srcu(&uverbs_dev->disassociate_srcu);
1142         event.event = IB_EVENT_DEVICE_FATAL;
1143         event.element.port_num = 0;
1144         event.device = ib_dev;
1145
1146         mutex_lock(&uverbs_dev->lists_mutex);
1147         while (!list_empty(&uverbs_dev->uverbs_file_list)) {
1148                 struct ib_ucontext *ucontext;
1149                 file = list_first_entry(&uverbs_dev->uverbs_file_list,
1150                                         struct ib_uverbs_file, list);
1151                 file->is_closed = 1;
1152                 list_del(&file->list);
1153                 kref_get(&file->ref);
1154                 mutex_unlock(&uverbs_dev->lists_mutex);
1155
1156                 ib_uverbs_event_handler(&file->event_handler, &event);
1157
1158                 mutex_lock(&file->cleanup_mutex);
1159                 ucontext = file->ucontext;
1160                 file->ucontext = NULL;
1161                 mutex_unlock(&file->cleanup_mutex);
1162
1163                 /* At this point ib_uverbs_close cannot be running
1164                  * ib_uverbs_cleanup_ucontext
1165                  */
1166                 if (ucontext) {
1167                         /* We must release the mutex before going ahead and
1168                          * calling disassociate_ucontext. disassociate_ucontext
1169                          * might end up indirectly calling uverbs_close,
1170                          * for example due to freeing the resources
1171                          * (e.g mmput).
1172                          */
1173                         ib_dev->disassociate_ucontext(ucontext);
1174                         mutex_lock(&file->cleanup_mutex);
1175                         ib_uverbs_cleanup_ucontext(file, ucontext, true);
1176                         mutex_unlock(&file->cleanup_mutex);
1177                 }
1178
1179                 mutex_lock(&uverbs_dev->lists_mutex);
1180                 kref_put(&file->ref, ib_uverbs_release_file);
1181         }
1182
1183         while (!list_empty(&uverbs_dev->uverbs_events_file_list)) {
1184                 event_file = list_first_entry(&uverbs_dev->
1185                                               uverbs_events_file_list,
1186                                               struct ib_uverbs_async_event_file,
1187                                               list);
1188                 spin_lock_irq(&event_file->ev_queue.lock);
1189                 event_file->ev_queue.is_closed = 1;
1190                 spin_unlock_irq(&event_file->ev_queue.lock);
1191
1192                 list_del(&event_file->list);
1193                 ib_unregister_event_handler(
1194                         &event_file->uverbs_file->event_handler);
1195                 event_file->uverbs_file->event_handler.device =
1196                         NULL;
1197
1198                 wake_up_interruptible(&event_file->ev_queue.poll_wait);
1199                 kill_fasync(&event_file->ev_queue.async_queue, SIGIO, POLL_IN);
1200         }
1201         mutex_unlock(&uverbs_dev->lists_mutex);
1202 }
1203
1204 static void ib_uverbs_remove_one(struct ib_device *device, void *client_data)
1205 {
1206         struct ib_uverbs_device *uverbs_dev = client_data;
1207         int wait_clients = 1;
1208
1209         if (!uverbs_dev)
1210                 return;
1211
1212         dev_set_drvdata(uverbs_dev->dev, NULL);
1213         device_destroy(uverbs_class, uverbs_dev->cdev.dev);
1214         cdev_del(&uverbs_dev->cdev);
1215
1216         if (uverbs_dev->devnum < IB_UVERBS_MAX_DEVICES)
1217                 clear_bit(uverbs_dev->devnum, dev_map);
1218         else
1219                 clear_bit(uverbs_dev->devnum - IB_UVERBS_MAX_DEVICES, overflow_map);
1220
1221         if (device->disassociate_ucontext) {
1222                 /* We disassociate HW resources and immediately return.
1223                  * Userspace will see a EIO errno for all future access.
1224                  * Upon returning, ib_device may be freed internally and is not
1225                  * valid any more.
1226                  * uverbs_device is still available until all clients close
1227                  * their files, then the uverbs device ref count will be zero
1228                  * and its resources will be freed.
1229                  * Note: At this point no more files can be opened since the
1230                  * cdev was deleted, however active clients can still issue
1231                  * commands and close their open files.
1232                  */
1233                 rcu_assign_pointer(uverbs_dev->ib_dev, NULL);
1234                 ib_uverbs_free_hw_resources(uverbs_dev, device);
1235                 wait_clients = 0;
1236         }
1237
1238         if (atomic_dec_and_test(&uverbs_dev->refcount))
1239                 ib_uverbs_comp_dev(uverbs_dev);
1240         if (wait_clients)
1241                 wait_for_completion(&uverbs_dev->comp);
1242         kobject_put(&uverbs_dev->kobj);
1243 }
1244
1245 static char *uverbs_devnode(struct device *dev, umode_t *mode)
1246 {
1247         if (mode)
1248                 *mode = 0666;
1249         return kasprintf(GFP_KERNEL, "infiniband/%s", dev_name(dev));
1250 }
1251
1252 static int __init ib_uverbs_init(void)
1253 {
1254         int ret;
1255
1256         ret = register_chrdev_region(IB_UVERBS_BASE_DEV, IB_UVERBS_MAX_DEVICES,
1257                                      "infiniband_verbs");
1258         if (ret) {
1259                 pr_err("user_verbs: couldn't register device number\n");
1260                 goto out;
1261         }
1262
1263         uverbs_class = class_create(THIS_MODULE, "infiniband_verbs");
1264         if (IS_ERR(uverbs_class)) {
1265                 ret = PTR_ERR(uverbs_class);
1266                 pr_err("user_verbs: couldn't create class infiniband_verbs\n");
1267                 goto out_chrdev;
1268         }
1269
1270         uverbs_class->devnode = uverbs_devnode;
1271
1272         ret = class_create_file(uverbs_class, &class_attr_abi_version.attr);
1273         if (ret) {
1274                 pr_err("user_verbs: couldn't create abi_version attribute\n");
1275                 goto out_class;
1276         }
1277
1278         ret = ib_register_client(&uverbs_client);
1279         if (ret) {
1280                 pr_err("user_verbs: couldn't register client\n");
1281                 goto out_class;
1282         }
1283
1284         return 0;
1285
1286 out_class:
1287         class_destroy(uverbs_class);
1288
1289 out_chrdev:
1290         unregister_chrdev_region(IB_UVERBS_BASE_DEV, IB_UVERBS_MAX_DEVICES);
1291
1292 out:
1293         return ret;
1294 }
1295
1296 static void __exit ib_uverbs_cleanup(void)
1297 {
1298         ib_unregister_client(&uverbs_client);
1299         class_destroy(uverbs_class);
1300         unregister_chrdev_region(IB_UVERBS_BASE_DEV, IB_UVERBS_MAX_DEVICES);
1301         if (overflow_maj)
1302                 unregister_chrdev_region(overflow_maj, IB_UVERBS_MAX_DEVICES);
1303 }
1304
1305 module_init(ib_uverbs_init);
1306 module_exit(ib_uverbs_cleanup);