ucma.c

   1/*
   2 * Copyright (c) 2005-2006 Intel Corporation.  All rights reserved.
   3 *
   4 * This software is available to you under a choice of one of two
   5 * licenses.  You may choose to be licensed under the terms of the GNU
   6 * General Public License (GPL) Version 2, available from the file
   7 * COPYING in the main directory of this source tree, or the
   8 * OpenIB.org BSD license below:
   9 *
  10 *     Redistribution and use in source and binary forms, with or
  11 *     without modification, are permitted provided that the following
  12 *     conditions are met:
  13 *
  14 *      - Redistributions of source code must retain the above
  15 *	copyright notice, this list of conditions and the following
  16 *	disclaimer.
  17 *
  18 *      - Redistributions in binary form must reproduce the above
  19 *	copyright notice, this list of conditions and the following
  20 *	disclaimer in the documentation and/or other materials
  21 *	provided with the distribution.
  22 *
  23 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  24 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  25 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  26 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  27 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  28 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  29 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  30 * SOFTWARE.
  31 */
  32
  33#include <linux/completion.h>
  34#include <linux/file.h>
  35#include <linux/mutex.h>
  36#include <linux/poll.h>
  37#include <linux/sched.h>
  38#include <linux/idr.h>
  39#include <linux/in.h>
  40#include <linux/in6.h>
  41#include <linux/miscdevice.h>
  42#include <linux/slab.h>
  43#include <linux/sysctl.h>
  44#include <linux/module.h>
  45#include <linux/nsproxy.h>
  46
  47#include <linux/nospec.h>
  48
  49#include <rdma/rdma_user_cm.h>
  50#include <rdma/ib_marshall.h>
  51#include <rdma/rdma_cm.h>
  52#include <rdma/rdma_cm_ib.h>
  53#include <rdma/ib_addr.h>
  54#include <rdma/ib.h>
  55#include <rdma/ib_cm.h>
  56#include <rdma/rdma_netlink.h>
  57#include "core_priv.h"
  58
  59MODULE_AUTHOR("Sean Hefty");
  60MODULE_DESCRIPTION("RDMA Userspace Connection Manager Access");
  61MODULE_LICENSE("Dual BSD/GPL");
  62
  63static unsigned int max_backlog = 1024;
  64
  65static struct ctl_table_header *ucma_ctl_table_hdr;
  66static struct ctl_table ucma_ctl_table[] = {
  67	{
  68		.procname	= "max_backlog",
  69		.data		= &max_backlog,
  70		.maxlen		= sizeof max_backlog,
  71		.mode		= 0644,
  72		.proc_handler	= proc_dointvec_minmax,
  73		.extra1		= SYSCTL_ZERO,
  74		.extra2		= SYSCTL_INT_MAX,
  75	},
  76};
  77
  78struct ucma_file {
  79	struct mutex		mut;
  80	struct file		*filp;
  81	struct list_head	ctx_list;
  82	struct list_head	event_list;
  83	wait_queue_head_t	poll_wait;
  84};
  85
  86struct ucma_context {
  87	u32			id;
  88	struct completion	comp;
  89	refcount_t		ref;
  90	int			events_reported;
  91	atomic_t		backlog;
  92
  93	struct ucma_file	*file;
  94	struct rdma_cm_id	*cm_id;
  95	struct mutex		mutex;
  96	u64			uid;
  97
  98	struct list_head	list;
  99	struct list_head	mc_list;
 100	struct work_struct	close_work;
 101};
 102
 103struct ucma_multicast {
 104	struct ucma_context	*ctx;
 105	u32			id;
 106	int			events_reported;
 107
 108	u64			uid;
 109	u8			join_state;
 110	struct list_head	list;
 111	struct sockaddr_storage	addr;
 112};
 113
 114struct ucma_event {
 115	struct ucma_context	*ctx;
 116	struct ucma_context	*conn_req_ctx;
 117	struct ucma_multicast	*mc;
 118	struct list_head	list;
 119	struct rdma_ucm_event_resp resp;
 120};
 121
 122static DEFINE_XARRAY_ALLOC(ctx_table);
 123static DEFINE_XARRAY_ALLOC(multicast_table);
 124
 125static const struct file_operations ucma_fops;
 126static int ucma_destroy_private_ctx(struct ucma_context *ctx);
 127
 128static inline struct ucma_context *_ucma_find_context(int id,
 129						      struct ucma_file *file)
 130{
 131	struct ucma_context *ctx;
 132
 133	ctx = xa_load(&ctx_table, id);
 134	if (!ctx)
 135		ctx = ERR_PTR(-ENOENT);
 136	else if (ctx->file != file)
 137		ctx = ERR_PTR(-EINVAL);
 138	return ctx;
 139}
 140
 141static struct ucma_context *ucma_get_ctx(struct ucma_file *file, int id)
 142{
 143	struct ucma_context *ctx;
 144
 145	xa_lock(&ctx_table);
 146	ctx = _ucma_find_context(id, file);
 147	if (!IS_ERR(ctx))
 148		if (!refcount_inc_not_zero(&ctx->ref))
 149			ctx = ERR_PTR(-ENXIO);
 150	xa_unlock(&ctx_table);
 151	return ctx;
 152}
 153
 154static void ucma_put_ctx(struct ucma_context *ctx)
 155{
 156	if (refcount_dec_and_test(&ctx->ref))
 157		complete(&ctx->comp);
 158}
 159
 160/*
 161 * Same as ucm_get_ctx but requires that ->cm_id->device is valid, eg that the
 162 * CM_ID is bound.
 163 */
 164static struct ucma_context *ucma_get_ctx_dev(struct ucma_file *file, int id)
 165{
 166	struct ucma_context *ctx = ucma_get_ctx(file, id);
 167
 168	if (IS_ERR(ctx))
 169		return ctx;
 170	if (!ctx->cm_id->device) {
 171		ucma_put_ctx(ctx);
 172		return ERR_PTR(-EINVAL);
 173	}
 174	return ctx;
 175}
 176
 177static void ucma_close_id(struct work_struct *work)
 178{
 179	struct ucma_context *ctx =  container_of(work, struct ucma_context, close_work);
 180
 181	/* once all inflight tasks are finished, we close all underlying
 182	 * resources. The context is still alive till its explicit destryoing
 183	 * by its creator. This puts back the xarray's reference.
 184	 */
 185	ucma_put_ctx(ctx);
 186	wait_for_completion(&ctx->comp);
 187	/* No new events will be generated after destroying the id. */
 188	rdma_destroy_id(ctx->cm_id);
 189
 190	/* Reading the cm_id without holding a positive ref is not allowed */
 191	ctx->cm_id = NULL;
 192}
 193
 194static struct ucma_context *ucma_alloc_ctx(struct ucma_file *file)
 195{
 196	struct ucma_context *ctx;
 197
 198	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
 199	if (!ctx)
 200		return NULL;
 201
 202	INIT_WORK(&ctx->close_work, ucma_close_id);
 203	init_completion(&ctx->comp);
 204	INIT_LIST_HEAD(&ctx->mc_list);
 205	/* So list_del() will work if we don't do ucma_finish_ctx() */
 206	INIT_LIST_HEAD(&ctx->list);
 207	ctx->file = file;
 208	mutex_init(&ctx->mutex);
 209
 210	if (xa_alloc(&ctx_table, &ctx->id, NULL, xa_limit_32b, GFP_KERNEL)) {
 211		kfree(ctx);
 212		return NULL;
 213	}
 214	return ctx;
 215}
 216
 217static void ucma_set_ctx_cm_id(struct ucma_context *ctx,
 218			       struct rdma_cm_id *cm_id)
 219{
 220	refcount_set(&ctx->ref, 1);
 221	ctx->cm_id = cm_id;
 222}
 223
 224static void ucma_finish_ctx(struct ucma_context *ctx)
 225{
 226	lockdep_assert_held(&ctx->file->mut);
 227	list_add_tail(&ctx->list, &ctx->file->ctx_list);
 228	xa_store(&ctx_table, ctx->id, ctx, GFP_KERNEL);
 229}
 230
 231static void ucma_copy_conn_event(struct rdma_ucm_conn_param *dst,
 232				 struct rdma_conn_param *src)
 233{
 234	if (src->private_data_len)
 235		memcpy(dst->private_data, src->private_data,
 236		       src->private_data_len);
 237	dst->private_data_len = src->private_data_len;
 238	dst->responder_resources = src->responder_resources;
 239	dst->initiator_depth = src->initiator_depth;
 240	dst->flow_control = src->flow_control;
 241	dst->retry_count = src->retry_count;
 242	dst->rnr_retry_count = src->rnr_retry_count;
 243	dst->srq = src->srq;
 244	dst->qp_num = src->qp_num;
 245}
 246
 247static void ucma_copy_ud_event(struct ib_device *device,
 248			       struct rdma_ucm_ud_param *dst,
 249			       struct rdma_ud_param *src)
 250{
 251	if (src->private_data_len)
 252		memcpy(dst->private_data, src->private_data,
 253		       src->private_data_len);
 254	dst->private_data_len = src->private_data_len;
 255	ib_copy_ah_attr_to_user(device, &dst->ah_attr, &src->ah_attr);
 256	dst->qp_num = src->qp_num;
 257	dst->qkey = src->qkey;
 258}
 259
 260static struct ucma_event *ucma_create_uevent(struct ucma_context *ctx,
 261					     struct rdma_cm_event *event)
 262{
 263	struct ucma_event *uevent;
 264
 265	uevent = kzalloc(sizeof(*uevent), GFP_KERNEL);
 266	if (!uevent)
 267		return NULL;
 268
 269	uevent->ctx = ctx;
 270	switch (event->event) {
 271	case RDMA_CM_EVENT_MULTICAST_JOIN:
 272	case RDMA_CM_EVENT_MULTICAST_ERROR:
 273		uevent->mc = (struct ucma_multicast *)
 274			     event->param.ud.private_data;
 275		uevent->resp.uid = uevent->mc->uid;
 276		uevent->resp.id = uevent->mc->id;
 277		break;
 278	default:
 279		uevent->resp.uid = ctx->uid;
 280		uevent->resp.id = ctx->id;
 281		break;
 282	}
 283	uevent->resp.event = event->event;
 284	uevent->resp.status = event->status;
 285
 286	if (event->event == RDMA_CM_EVENT_ADDRINFO_RESOLVED)
 287		goto out;
 288
 289	if (ctx->cm_id->qp_type == IB_QPT_UD)
 290		ucma_copy_ud_event(ctx->cm_id->device, &uevent->resp.param.ud,
 291				   &event->param.ud);
 292	else
 293		ucma_copy_conn_event(&uevent->resp.param.conn,
 294				     &event->param.conn);
 295
 296out:
 297	uevent->resp.ece.vendor_id = event->ece.vendor_id;
 298	uevent->resp.ece.attr_mod = event->ece.attr_mod;
 299	return uevent;
 300}
 301
 302static int ucma_connect_event_handler(struct rdma_cm_id *cm_id,
 303				      struct rdma_cm_event *event)
 304{
 305	struct ucma_context *listen_ctx = cm_id->context;
 306	struct ucma_context *ctx;
 307	struct ucma_event *uevent;
 308
 309	if (!atomic_add_unless(&listen_ctx->backlog, -1, 0))
 310		return -ENOMEM;
 311	ctx = ucma_alloc_ctx(listen_ctx->file);
 312	if (!ctx)
 313		goto err_backlog;
 314	ucma_set_ctx_cm_id(ctx, cm_id);
 315
 316	uevent = ucma_create_uevent(listen_ctx, event);
 317	if (!uevent)
 318		goto err_alloc;
 319	uevent->conn_req_ctx = ctx;
 320	uevent->resp.id = ctx->id;
 321
 322	ctx->cm_id->context = ctx;
 323
 324	mutex_lock(&ctx->file->mut);
 325	ucma_finish_ctx(ctx);
 326	list_add_tail(&uevent->list, &ctx->file->event_list);
 327	mutex_unlock(&ctx->file->mut);
 328	wake_up_interruptible(&ctx->file->poll_wait);
 329	return 0;
 330
 331err_alloc:
 332	ucma_destroy_private_ctx(ctx);
 333err_backlog:
 334	atomic_inc(&listen_ctx->backlog);
 335	/* Returning error causes the new ID to be destroyed */
 336	return -ENOMEM;
 337}
 338
 339static int ucma_event_handler(struct rdma_cm_id *cm_id,
 340			      struct rdma_cm_event *event)
 341{
 342	struct ucma_event *uevent;
 343	struct ucma_context *ctx = cm_id->context;
 344
 345	if (event->event == RDMA_CM_EVENT_CONNECT_REQUEST)
 346		return ucma_connect_event_handler(cm_id, event);
 347
 348	/*
 349	 * We ignore events for new connections until userspace has set their
 350	 * context.  This can only happen if an error occurs on a new connection
 351	 * before the user accepts it.  This is okay, since the accept will just
 352	 * fail later. However, we do need to release the underlying HW
 353	 * resources in case of a device removal event.
 354	 */
 355	if (ctx->uid) {
 356		uevent = ucma_create_uevent(ctx, event);
 357		if (!uevent)
 358			return 0;
 359
 360		mutex_lock(&ctx->file->mut);
 361		list_add_tail(&uevent->list, &ctx->file->event_list);
 362		mutex_unlock(&ctx->file->mut);
 363		wake_up_interruptible(&ctx->file->poll_wait);
 364	}
 365
 366	if (event->event == RDMA_CM_EVENT_DEVICE_REMOVAL) {
 367		xa_lock(&ctx_table);
 368		if (xa_load(&ctx_table, ctx->id) == ctx)
 369			queue_work(system_dfl_wq, &ctx->close_work);
 370		xa_unlock(&ctx_table);
 371	}
 372	return 0;
 373}
 374
 375static ssize_t ucma_get_event(struct ucma_file *file, const char __user *inbuf,
 376			      int in_len, int out_len)
 377{
 378	struct rdma_ucm_get_event cmd;
 379	struct ucma_event *uevent;
 380
 381	/*
 382	 * Old 32 bit user space does not send the 4 byte padding in the
 383	 * reserved field. We don't care, allow it to keep working.
 384	 */
 385	if (out_len < sizeof(uevent->resp) - sizeof(uevent->resp.reserved) -
 386			      sizeof(uevent->resp.ece))
 387		return -ENOSPC;
 388
 389	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
 390		return -EFAULT;
 391
 392	mutex_lock(&file->mut);
 393	while (list_empty(&file->event_list)) {
 394		mutex_unlock(&file->mut);
 395
 396		if (file->filp->f_flags & O_NONBLOCK)
 397			return -EAGAIN;
 398
 399		if (wait_event_interruptible(file->poll_wait,
 400					     !list_empty(&file->event_list)))
 401			return -ERESTARTSYS;
 402
 403		mutex_lock(&file->mut);
 404	}
 405
 406	uevent = list_first_entry(&file->event_list, struct ucma_event, list);
 407
 408	if (copy_to_user(u64_to_user_ptr(cmd.response),
 409			 &uevent->resp,
 410			 min_t(size_t, out_len, sizeof(uevent->resp)))) {
 411		mutex_unlock(&file->mut);
 412		return -EFAULT;
 413	}
 414
 415	list_del(&uevent->list);
 416	uevent->ctx->events_reported++;
 417	if (uevent->mc)
 418		uevent->mc->events_reported++;
 419	if (uevent->resp.event == RDMA_CM_EVENT_CONNECT_REQUEST)
 420		atomic_inc(&uevent->ctx->backlog);
 421	mutex_unlock(&file->mut);
 422
 423	kfree(uevent);
 424	return 0;
 425}
 426
 427static int ucma_get_qp_type(struct rdma_ucm_create_id *cmd, enum ib_qp_type *qp_type)
 428{
 429	switch (cmd->ps) {
 430	case RDMA_PS_TCP:
 431		*qp_type = IB_QPT_RC;
 432		return 0;
 433	case RDMA_PS_UDP:
 434	case RDMA_PS_IPOIB:
 435		*qp_type = IB_QPT_UD;
 436		return 0;
 437	case RDMA_PS_IB:
 438		*qp_type = cmd->qp_type;
 439		return 0;
 440	default:
 441		return -EINVAL;
 442	}
 443}
 444
 445static ssize_t ucma_create_id(struct ucma_file *file, const char __user *inbuf,
 446			      int in_len, int out_len)
 447{
 448	struct rdma_ucm_create_id cmd;
 449	struct rdma_ucm_create_id_resp resp;
 450	struct ucma_context *ctx;
 451	struct rdma_cm_id *cm_id;
 452	enum ib_qp_type qp_type;
 453	int ret;
 454
 455	if (out_len < sizeof(resp))
 456		return -ENOSPC;
 457
 458	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
 459		return -EFAULT;
 460
 461	ret = ucma_get_qp_type(&cmd, &qp_type);
 462	if (ret)
 463		return ret;
 464
 465	ctx = ucma_alloc_ctx(file);
 466	if (!ctx)
 467		return -ENOMEM;
 468
 469	ctx->uid = cmd.uid;
 470	cm_id = rdma_create_user_id(ucma_event_handler, ctx, cmd.ps, qp_type);
 471	if (IS_ERR(cm_id)) {
 472		ret = PTR_ERR(cm_id);
 473		goto err1;
 474	}
 475	ucma_set_ctx_cm_id(ctx, cm_id);
 476
 477	resp.id = ctx->id;
 478	if (copy_to_user(u64_to_user_ptr(cmd.response),
 479			 &resp, sizeof(resp))) {
 480		ret = -EFAULT;
 481		goto err1;
 482	}
 483
 484	mutex_lock(&file->mut);
 485	ucma_finish_ctx(ctx);
 486	mutex_unlock(&file->mut);
 487	return 0;
 488
 489err1:
 490	ucma_destroy_private_ctx(ctx);
 491	return ret;
 492}
 493
 494static void ucma_cleanup_multicast(struct ucma_context *ctx)
 495{
 496	struct ucma_multicast *mc, *tmp;
 497
 498	xa_lock(&multicast_table);
 499	list_for_each_entry_safe(mc, tmp, &ctx->mc_list, list) {
 500		list_del(&mc->list);
 501		/*
 502		 * At this point mc->ctx->ref is 0 so the mc cannot leave the
 503		 * lock on the reader and this is enough serialization
 504		 */
 505		__xa_erase(&multicast_table, mc->id);
 506		kfree(mc);
 507	}
 508	xa_unlock(&multicast_table);
 509}
 510
 511static void ucma_cleanup_mc_events(struct ucma_multicast *mc)
 512{
 513	struct ucma_event *uevent, *tmp;
 514
 515	rdma_lock_handler(mc->ctx->cm_id);
 516	mutex_lock(&mc->ctx->file->mut);
 517	list_for_each_entry_safe(uevent, tmp, &mc->ctx->file->event_list, list) {
 518		if (uevent->mc != mc)
 519			continue;
 520
 521		list_del(&uevent->list);
 522		kfree(uevent);
 523	}
 524	mutex_unlock(&mc->ctx->file->mut);
 525	rdma_unlock_handler(mc->ctx->cm_id);
 526}
 527
 528static int ucma_cleanup_ctx_events(struct ucma_context *ctx)
 529{
 530	int events_reported;
 531	struct ucma_event *uevent, *tmp;
 532	LIST_HEAD(list);
 533
 534	/* Cleanup events not yet reported to the user.*/
 535	mutex_lock(&ctx->file->mut);
 536	list_for_each_entry_safe(uevent, tmp, &ctx->file->event_list, list) {
 537		if (uevent->ctx != ctx)
 538			continue;
 539
 540		if (uevent->resp.event == RDMA_CM_EVENT_CONNECT_REQUEST &&
 541		    xa_cmpxchg(&ctx_table, uevent->conn_req_ctx->id,
 542			       uevent->conn_req_ctx, XA_ZERO_ENTRY,
 543			       GFP_KERNEL) == uevent->conn_req_ctx) {
 544			list_move_tail(&uevent->list, &list);
 545			continue;
 546		}
 547		list_del(&uevent->list);
 548		kfree(uevent);
 549	}
 550	list_del(&ctx->list);
 551	events_reported = ctx->events_reported;
 552	mutex_unlock(&ctx->file->mut);
 553
 554	/*
 555	 * If this was a listening ID then any connections spawned from it that
 556	 * have not been delivered to userspace are cleaned up too. Must be done
 557	 * outside any locks.
 558	 */
 559	list_for_each_entry_safe(uevent, tmp, &list, list) {
 560		ucma_destroy_private_ctx(uevent->conn_req_ctx);
 561		kfree(uevent);
 562	}
 563	return events_reported;
 564}
 565
 566/*
 567 * When this is called the xarray must have a XA_ZERO_ENTRY in the ctx->id (ie
 568 * the ctx is not public to the user). This either because:
 569 *  - ucma_finish_ctx() hasn't been called
 570 *  - xa_cmpxchg() succeed to remove the entry (only one thread can succeed)
 571 */
 572static int ucma_destroy_private_ctx(struct ucma_context *ctx)
 573{
 574	int events_reported;
 575
 576	/*
 577	 * Destroy the underlying cm_id. New work queuing is prevented now by
 578	 * the removal from the xarray. Once the work is cancled ref will either
 579	 * be 0 because the work ran to completion and consumed the ref from the
 580	 * xarray, or it will be positive because we still have the ref from the
 581	 * xarray. This can also be 0 in cases where cm_id was never set
 582	 */
 583	cancel_work_sync(&ctx->close_work);
 584	if (refcount_read(&ctx->ref))
 585		ucma_close_id(&ctx->close_work);
 586
 587	events_reported = ucma_cleanup_ctx_events(ctx);
 588	ucma_cleanup_multicast(ctx);
 589
 590	WARN_ON(xa_cmpxchg(&ctx_table, ctx->id, XA_ZERO_ENTRY, NULL,
 591			   GFP_KERNEL) != NULL);
 592	mutex_destroy(&ctx->mutex);
 593	kfree(ctx);
 594	return events_reported;
 595}
 596
 597static ssize_t ucma_destroy_id(struct ucma_file *file, const char __user *inbuf,
 598			       int in_len, int out_len)
 599{
 600	struct rdma_ucm_destroy_id cmd;
 601	struct rdma_ucm_destroy_id_resp resp;
 602	struct ucma_context *ctx;
 603	int ret = 0;
 604
 605	if (out_len < sizeof(resp))
 606		return -ENOSPC;
 607
 608	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
 609		return -EFAULT;
 610
 611	xa_lock(&ctx_table);
 612	ctx = _ucma_find_context(cmd.id, file);
 613	if (!IS_ERR(ctx)) {
 614		if (__xa_cmpxchg(&ctx_table, ctx->id, ctx, XA_ZERO_ENTRY,
 615				 GFP_KERNEL) != ctx)
 616			ctx = ERR_PTR(-ENOENT);
 617	}
 618	xa_unlock(&ctx_table);
 619
 620	if (IS_ERR(ctx))
 621		return PTR_ERR(ctx);
 622
 623	resp.events_reported = ucma_destroy_private_ctx(ctx);
 624	if (copy_to_user(u64_to_user_ptr(cmd.response),
 625			 &resp, sizeof(resp)))
 626		ret = -EFAULT;
 627
 628	return ret;
 629}
 630
 631static ssize_t ucma_bind_ip(struct ucma_file *file, const char __user *inbuf,
 632			      int in_len, int out_len)
 633{
 634	struct rdma_ucm_bind_ip cmd;
 635	struct ucma_context *ctx;
 636	int ret;
 637
 638	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
 639		return -EFAULT;
 640
 641	if (!rdma_addr_size_in6(&cmd.addr))
 642		return -EINVAL;
 643
 644	ctx = ucma_get_ctx(file, cmd.id);
 645	if (IS_ERR(ctx))
 646		return PTR_ERR(ctx);
 647
 648	mutex_lock(&ctx->mutex);
 649	ret = rdma_bind_addr(ctx->cm_id, (struct sockaddr *) &cmd.addr);
 650	mutex_unlock(&ctx->mutex);
 651
 652	ucma_put_ctx(ctx);
 653	return ret;
 654}
 655
 656static ssize_t ucma_bind(struct ucma_file *file, const char __user *inbuf,
 657			 int in_len, int out_len)
 658{
 659	struct rdma_ucm_bind cmd;
 660	struct ucma_context *ctx;
 661	int ret;
 662
 663	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
 664		return -EFAULT;
 665
 666	if (cmd.reserved || !cmd.addr_size ||
 667	    cmd.addr_size != rdma_addr_size_kss(&cmd.addr))
 668		return -EINVAL;
 669
 670	ctx = ucma_get_ctx(file, cmd.id);
 671	if (IS_ERR(ctx))
 672		return PTR_ERR(ctx);
 673
 674	mutex_lock(&ctx->mutex);
 675	ret = rdma_bind_addr(ctx->cm_id, (struct sockaddr *) &cmd.addr);
 676	mutex_unlock(&ctx->mutex);
 677	ucma_put_ctx(ctx);
 678	return ret;
 679}
 680
 681static ssize_t ucma_resolve_ip(struct ucma_file *file,
 682			       const char __user *inbuf,
 683			       int in_len, int out_len)
 684{
 685	struct rdma_ucm_resolve_ip cmd;
 686	struct ucma_context *ctx;
 687	int ret;
 688
 689	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
 690		return -EFAULT;
 691
 692	if ((cmd.src_addr.sin6_family && !rdma_addr_size_in6(&cmd.src_addr)) ||
 693	    !rdma_addr_size_in6(&cmd.dst_addr))
 694		return -EINVAL;
 695
 696	ctx = ucma_get_ctx(file, cmd.id);
 697	if (IS_ERR(ctx))
 698		return PTR_ERR(ctx);
 699
 700	mutex_lock(&ctx->mutex);
 701	ret = rdma_resolve_addr(ctx->cm_id, (struct sockaddr *) &cmd.src_addr,
 702				(struct sockaddr *) &cmd.dst_addr, cmd.timeout_ms);
 703	mutex_unlock(&ctx->mutex);
 704	ucma_put_ctx(ctx);
 705	return ret;
 706}
 707
 708static ssize_t ucma_resolve_addr(struct ucma_file *file,
 709				 const char __user *inbuf,
 710				 int in_len, int out_len)
 711{
 712	struct rdma_ucm_resolve_addr cmd;
 713	struct ucma_context *ctx;
 714	int ret;
 715
 716	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
 717		return -EFAULT;
 718
 719	if (cmd.reserved ||
 720	    (cmd.src_size && (cmd.src_size != rdma_addr_size_kss(&cmd.src_addr))) ||
 721	    !cmd.dst_size || (cmd.dst_size != rdma_addr_size_kss(&cmd.dst_addr)))
 722		return -EINVAL;
 723
 724	ctx = ucma_get_ctx(file, cmd.id);
 725	if (IS_ERR(ctx))
 726		return PTR_ERR(ctx);
 727
 728	mutex_lock(&ctx->mutex);
 729	ret = rdma_resolve_addr(ctx->cm_id, (struct sockaddr *) &cmd.src_addr,
 730				(struct sockaddr *) &cmd.dst_addr, cmd.timeout_ms);
 731	mutex_unlock(&ctx->mutex);
 732	ucma_put_ctx(ctx);
 733	return ret;
 734}
 735
 736static ssize_t ucma_resolve_ib_service(struct ucma_file *file,
 737				       const char __user *inbuf, int in_len,
 738				       int out_len)
 739{
 740	struct rdma_ucm_resolve_ib_service cmd;
 741	struct ucma_context *ctx;
 742	int ret;
 743
 744	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
 745		return -EFAULT;
 746
 747	ctx = ucma_get_ctx(file, cmd.id);
 748	if (IS_ERR(ctx))
 749		return PTR_ERR(ctx);
 750
 751	mutex_lock(&ctx->mutex);
 752	ret = rdma_resolve_ib_service(ctx->cm_id, &cmd.ibs);
 753	mutex_unlock(&ctx->mutex);
 754	ucma_put_ctx(ctx);
 755	return ret;
 756}
 757
 758static ssize_t ucma_resolve_route(struct ucma_file *file,
 759				  const char __user *inbuf,
 760				  int in_len, int out_len)
 761{
 762	struct rdma_ucm_resolve_route cmd;
 763	struct ucma_context *ctx;
 764	int ret;
 765
 766	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
 767		return -EFAULT;
 768
 769	ctx = ucma_get_ctx_dev(file, cmd.id);
 770	if (IS_ERR(ctx))
 771		return PTR_ERR(ctx);
 772
 773	mutex_lock(&ctx->mutex);
 774	ret = rdma_resolve_route(ctx->cm_id, cmd.timeout_ms);
 775	mutex_unlock(&ctx->mutex);
 776	ucma_put_ctx(ctx);
 777	return ret;
 778}
 779
 780static void ucma_copy_ib_route(struct rdma_ucm_query_route_resp *resp,
 781			       struct rdma_route *route)
 782{
 783	struct rdma_dev_addr *dev_addr;
 784
 785	resp->num_paths = route->num_pri_alt_paths;
 786	switch (route->num_pri_alt_paths) {
 787	case 0:
 788		dev_addr = &route->addr.dev_addr;
 789		rdma_addr_get_dgid(dev_addr,
 790				   (union ib_gid *) &resp->ib_route[0].dgid);
 791		rdma_addr_get_sgid(dev_addr,
 792				   (union ib_gid *) &resp->ib_route[0].sgid);
 793		resp->ib_route[0].pkey = cpu_to_be16(ib_addr_get_pkey(dev_addr));
 794		break;
 795	case 2:
 796		ib_copy_path_rec_to_user(&resp->ib_route[1],
 797					 &route->path_rec[1]);
 798		fallthrough;
 799	case 1:
 800		ib_copy_path_rec_to_user(&resp->ib_route[0],
 801					 &route->path_rec[0]);
 802		break;
 803	default:
 804		break;
 805	}
 806}
 807
 808static void ucma_copy_iboe_route(struct rdma_ucm_query_route_resp *resp,
 809				 struct rdma_route *route)
 810{
 811
 812	resp->num_paths = route->num_pri_alt_paths;
 813	switch (route->num_pri_alt_paths) {
 814	case 0:
 815		rdma_ip2gid((struct sockaddr *)&route->addr.dst_addr,
 816			    (union ib_gid *)&resp->ib_route[0].dgid);
 817		rdma_ip2gid((struct sockaddr *)&route->addr.src_addr,
 818			    (union ib_gid *)&resp->ib_route[0].sgid);
 819		resp->ib_route[0].pkey = cpu_to_be16(0xffff);
 820		break;
 821	case 2:
 822		ib_copy_path_rec_to_user(&resp->ib_route[1],
 823					 &route->path_rec[1]);
 824		fallthrough;
 825	case 1:
 826		ib_copy_path_rec_to_user(&resp->ib_route[0],
 827					 &route->path_rec[0]);
 828		break;
 829	default:
 830		break;
 831	}
 832}
 833
 834static void ucma_copy_iw_route(struct rdma_ucm_query_route_resp *resp,
 835			       struct rdma_route *route)
 836{
 837	struct rdma_dev_addr *dev_addr;
 838
 839	dev_addr = &route->addr.dev_addr;
 840	rdma_addr_get_dgid(dev_addr, (union ib_gid *) &resp->ib_route[0].dgid);
 841	rdma_addr_get_sgid(dev_addr, (union ib_gid *) &resp->ib_route[0].sgid);
 842}
 843
 844static ssize_t ucma_query_route(struct ucma_file *file,
 845				const char __user *inbuf,
 846				int in_len, int out_len)
 847{
 848	struct rdma_ucm_query cmd;
 849	struct rdma_ucm_query_route_resp resp;
 850	struct ucma_context *ctx;
 851	struct sockaddr *addr;
 852	int ret = 0;
 853
 854	if (out_len < offsetof(struct rdma_ucm_query_route_resp, ibdev_index))
 855		return -ENOSPC;
 856
 857	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
 858		return -EFAULT;
 859
 860	ctx = ucma_get_ctx(file, cmd.id);
 861	if (IS_ERR(ctx))
 862		return PTR_ERR(ctx);
 863
 864	mutex_lock(&ctx->mutex);
 865	memset(&resp, 0, sizeof resp);
 866	addr = (struct sockaddr *) &ctx->cm_id->route.addr.src_addr;
 867	memcpy(&resp.src_addr, addr, addr->sa_family == AF_INET ?
 868				     sizeof(struct sockaddr_in) :
 869				     sizeof(struct sockaddr_in6));
 870	addr = (struct sockaddr *) &ctx->cm_id->route.addr.dst_addr;
 871	memcpy(&resp.dst_addr, addr, addr->sa_family == AF_INET ?
 872				     sizeof(struct sockaddr_in) :
 873				     sizeof(struct sockaddr_in6));
 874	if (!ctx->cm_id->device)
 875		goto out;
 876
 877	resp.node_guid = (__force __u64) ctx->cm_id->device->node_guid;
 878	resp.ibdev_index = ctx->cm_id->device->index;
 879	resp.port_num = ctx->cm_id->port_num;
 880
 881	if (rdma_cap_ib_sa(ctx->cm_id->device, ctx->cm_id->port_num))
 882		ucma_copy_ib_route(&resp, &ctx->cm_id->route);
 883	else if (rdma_protocol_roce(ctx->cm_id->device, ctx->cm_id->port_num))
 884		ucma_copy_iboe_route(&resp, &ctx->cm_id->route);
 885	else if (rdma_protocol_iwarp(ctx->cm_id->device, ctx->cm_id->port_num))
 886		ucma_copy_iw_route(&resp, &ctx->cm_id->route);
 887
 888out:
 889	mutex_unlock(&ctx->mutex);
 890	if (copy_to_user(u64_to_user_ptr(cmd.response), &resp,
 891			 min_t(size_t, out_len, sizeof(resp))))
 892		ret = -EFAULT;
 893
 894	ucma_put_ctx(ctx);
 895	return ret;
 896}
 897
 898static void ucma_query_device_addr(struct rdma_cm_id *cm_id,
 899				   struct rdma_ucm_query_addr_resp *resp)
 900{
 901	if (!cm_id->device)
 902		return;
 903
 904	resp->node_guid = (__force __u64) cm_id->device->node_guid;
 905	resp->ibdev_index = cm_id->device->index;
 906	resp->port_num = cm_id->port_num;
 907	resp->pkey = (__force __u16) cpu_to_be16(
 908		     ib_addr_get_pkey(&cm_id->route.addr.dev_addr));
 909}
 910
 911static ssize_t ucma_query_addr(struct ucma_context *ctx,
 912			       void __user *response, int out_len)
 913{
 914	struct rdma_ucm_query_addr_resp resp;
 915	struct sockaddr *addr;
 916	int ret = 0;
 917
 918	if (out_len < offsetof(struct rdma_ucm_query_addr_resp, ibdev_index))
 919		return -ENOSPC;
 920
 921	memset(&resp, 0, sizeof resp);
 922
 923	addr = (struct sockaddr *) &ctx->cm_id->route.addr.src_addr;
 924	resp.src_size = rdma_addr_size(addr);
 925	memcpy(&resp.src_addr, addr, resp.src_size);
 926
 927	addr = (struct sockaddr *) &ctx->cm_id->route.addr.dst_addr;
 928	resp.dst_size = rdma_addr_size(addr);
 929	memcpy(&resp.dst_addr, addr, resp.dst_size);
 930
 931	ucma_query_device_addr(ctx->cm_id, &resp);
 932
 933	if (copy_to_user(response, &resp, min_t(size_t, out_len, sizeof(resp))))
 934		ret = -EFAULT;
 935
 936	return ret;
 937}
 938
 939static ssize_t ucma_query_path(struct ucma_context *ctx,
 940			       void __user *response, int out_len)
 941{
 942	struct rdma_ucm_query_path_resp *resp;
 943	int i, ret = 0;
 944
 945	if (out_len < sizeof(*resp))
 946		return -ENOSPC;
 947
 948	resp = kzalloc(out_len, GFP_KERNEL);
 949	if (!resp)
 950		return -ENOMEM;
 951
 952	resp->num_paths = ctx->cm_id->route.num_pri_alt_paths;
 953	for (i = 0, out_len -= sizeof(*resp);
 954	     i < resp->num_paths && out_len > sizeof(struct ib_path_rec_data);
 955	     i++, out_len -= sizeof(struct ib_path_rec_data)) {
 956		struct sa_path_rec *rec = &ctx->cm_id->route.path_rec[i];
 957
 958		resp->path_data[i].flags = IB_PATH_GMP | IB_PATH_PRIMARY |
 959					   IB_PATH_BIDIRECTIONAL;
 960		if (rec->rec_type == SA_PATH_REC_TYPE_OPA) {
 961			struct sa_path_rec ib;
 962
 963			sa_convert_path_opa_to_ib(&ib, rec);
 964			ib_sa_pack_path(&ib, &resp->path_data[i].path_rec);
 965
 966		} else {
 967			ib_sa_pack_path(rec, &resp->path_data[i].path_rec);
 968		}
 969	}
 970
 971	if (copy_to_user(response, resp, struct_size(resp, path_data, i)))
 972		ret = -EFAULT;
 973
 974	kfree(resp);
 975	return ret;
 976}
 977
 978static ssize_t ucma_query_gid(struct ucma_context *ctx,
 979			      void __user *response, int out_len)
 980{
 981	struct rdma_ucm_query_addr_resp resp;
 982	struct sockaddr_ib *addr;
 983	int ret = 0;
 984
 985	if (out_len < offsetof(struct rdma_ucm_query_addr_resp, ibdev_index))
 986		return -ENOSPC;
 987
 988	memset(&resp, 0, sizeof resp);
 989
 990	ucma_query_device_addr(ctx->cm_id, &resp);
 991
 992	addr = (struct sockaddr_ib *) &resp.src_addr;
 993	resp.src_size = sizeof(*addr);
 994	if (ctx->cm_id->route.addr.src_addr.ss_family == AF_IB) {
 995		memcpy(addr, &ctx->cm_id->route.addr.src_addr, resp.src_size);
 996	} else {
 997		addr->sib_family = AF_IB;
 998		addr->sib_pkey = (__force __be16) resp.pkey;
 999		rdma_read_gids(ctx->cm_id, (union ib_gid *)&addr->sib_addr,
1000			       NULL);
1001		addr->sib_sid = rdma_get_service_id(ctx->cm_id, (struct sockaddr *)
1002						    &ctx->cm_id->route.addr.src_addr);
1003	}
1004
1005	addr = (struct sockaddr_ib *) &resp.dst_addr;
1006	resp.dst_size = sizeof(*addr);
1007	if (ctx->cm_id->route.addr.dst_addr.ss_family == AF_IB) {
1008		memcpy(addr, &ctx->cm_id->route.addr.dst_addr, resp.dst_size);
1009	} else {
1010		addr->sib_family = AF_IB;
1011		addr->sib_pkey = (__force __be16) resp.pkey;
1012		rdma_read_gids(ctx->cm_id, NULL,
1013			       (union ib_gid *)&addr->sib_addr);
1014		addr->sib_sid = rdma_get_service_id(ctx->cm_id, (struct sockaddr *)
1015						    &ctx->cm_id->route.addr.dst_addr);
1016	}
1017
1018	if (copy_to_user(response, &resp, min_t(size_t, out_len, sizeof(resp))))
1019		ret = -EFAULT;
1020
1021	return ret;
1022}
1023
1024static ssize_t ucma_query_ib_service(struct ucma_context *ctx,
1025				     void __user *response, int out_len)
1026{
1027	struct rdma_ucm_query_ib_service_resp *resp;
1028	int n, ret = 0;
1029
1030	if (out_len < sizeof(struct rdma_ucm_query_ib_service_resp))
1031		return -ENOSPC;
1032
1033	if (!ctx->cm_id->route.service_recs)
1034		return -ENODATA;
1035
1036	resp = kzalloc(out_len, GFP_KERNEL);
1037	if (!resp)
1038		return -ENOMEM;
1039
1040	resp->num_service_recs = ctx->cm_id->route.num_service_recs;
1041
1042	n = (out_len - sizeof(struct rdma_ucm_query_ib_service_resp)) /
1043		sizeof(struct ib_user_service_rec);
1044
1045	if (!n)
1046		goto out;
1047
1048	if (n > ctx->cm_id->route.num_service_recs)
1049		n = ctx->cm_id->route.num_service_recs;
1050
1051	memcpy(resp->recs, ctx->cm_id->route.service_recs,
1052	       sizeof(*resp->recs) * n);
1053	if (copy_to_user(response, resp, struct_size(resp, recs, n)))
1054		ret = -EFAULT;
1055
1056out:
1057	kfree(resp);
1058	return ret;
1059}
1060
1061static ssize_t ucma_query(struct ucma_file *file,
1062			  const char __user *inbuf,
1063			  int in_len, int out_len)
1064{
1065	struct rdma_ucm_query cmd;
1066	struct ucma_context *ctx;
1067	void __user *response;
1068	int ret;
1069
1070	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
1071		return -EFAULT;
1072
1073	response = u64_to_user_ptr(cmd.response);
1074	ctx = ucma_get_ctx(file, cmd.id);
1075	if (IS_ERR(ctx))
1076		return PTR_ERR(ctx);
1077
1078	mutex_lock(&ctx->mutex);
1079	switch (cmd.option) {
1080	case RDMA_USER_CM_QUERY_ADDR:
1081		ret = ucma_query_addr(ctx, response, out_len);
1082		break;
1083	case RDMA_USER_CM_QUERY_PATH:
1084		ret = ucma_query_path(ctx, response, out_len);
1085		break;
1086	case RDMA_USER_CM_QUERY_GID:
1087		ret = ucma_query_gid(ctx, response, out_len);
1088		break;
1089	case RDMA_USER_CM_QUERY_IB_SERVICE:
1090		ret = ucma_query_ib_service(ctx, response, out_len);
1091		break;
1092	default:
1093		ret = -ENOSYS;
1094		break;
1095	}
1096	mutex_unlock(&ctx->mutex);
1097
1098	ucma_put_ctx(ctx);
1099	return ret;
1100}
1101
1102static void ucma_copy_conn_param(struct rdma_cm_id *id,
1103				 struct rdma_conn_param *dst,
1104				 struct rdma_ucm_conn_param *src)
1105{
1106	dst->private_data = src->private_data;
1107	dst->private_data_len = src->private_data_len;
1108	dst->responder_resources = src->responder_resources;
1109	dst->initiator_depth = src->initiator_depth;
1110	dst->flow_control = src->flow_control;
1111	dst->retry_count = src->retry_count;
1112	dst->rnr_retry_count = src->rnr_retry_count;
1113	dst->srq = src->srq;
1114	dst->qp_num = src->qp_num & 0xFFFFFF;
1115	dst->qkey = (id->route.addr.src_addr.ss_family == AF_IB) ? src->qkey : 0;
1116}
1117
1118static ssize_t ucma_connect(struct ucma_file *file, const char __user *inbuf,
1119			    int in_len, int out_len)
1120{
1121	struct rdma_conn_param conn_param;
1122	struct rdma_ucm_ece ece = {};
1123	struct rdma_ucm_connect cmd;
1124	struct ucma_context *ctx;
1125	size_t in_size;
1126	int ret;
1127
1128	if (in_len < offsetofend(typeof(cmd), reserved))
1129		return -EINVAL;
1130	in_size = min_t(size_t, in_len, sizeof(cmd));
1131	if (copy_from_user(&cmd, inbuf, in_size))
1132		return -EFAULT;
1133
1134	if (!cmd.conn_param.valid)
1135		return -EINVAL;
1136
1137	ctx = ucma_get_ctx_dev(file, cmd.id);
1138	if (IS_ERR(ctx))
1139		return PTR_ERR(ctx);
1140
1141	ucma_copy_conn_param(ctx->cm_id, &conn_param, &cmd.conn_param);
1142	if (offsetofend(typeof(cmd), ece) <= in_size) {
1143		ece.vendor_id = cmd.ece.vendor_id;
1144		ece.attr_mod = cmd.ece.attr_mod;
1145	}
1146
1147	mutex_lock(&ctx->mutex);
1148	ret = rdma_connect_ece(ctx->cm_id, &conn_param, &ece);
1149	mutex_unlock(&ctx->mutex);
1150	ucma_put_ctx(ctx);
1151	return ret;
1152}
1153
1154static ssize_t ucma_listen(struct ucma_file *file, const char __user *inbuf,
1155			   int in_len, int out_len)
1156{
1157	struct rdma_ucm_listen cmd;
1158	struct ucma_context *ctx;
1159	int ret;
1160
1161	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
1162		return -EFAULT;
1163
1164	ctx = ucma_get_ctx(file, cmd.id);
1165	if (IS_ERR(ctx))
1166		return PTR_ERR(ctx);
1167
1168	if (cmd.backlog <= 0 || cmd.backlog > max_backlog)
1169		cmd.backlog = max_backlog;
1170	atomic_set(&ctx->backlog, cmd.backlog);
1171
1172	mutex_lock(&ctx->mutex);
1173	ret = rdma_listen(ctx->cm_id, cmd.backlog);
1174	mutex_unlock(&ctx->mutex);
1175	ucma_put_ctx(ctx);
1176	return ret;
1177}
1178
1179static ssize_t ucma_accept(struct ucma_file *file, const char __user *inbuf,
1180			   int in_len, int out_len)
1181{
1182	struct rdma_ucm_accept cmd;
1183	struct rdma_conn_param conn_param;
1184	struct rdma_ucm_ece ece = {};
1185	struct ucma_context *ctx;
1186	size_t in_size;
1187	int ret;
1188
1189	if (in_len < offsetofend(typeof(cmd), reserved))
1190		return -EINVAL;
1191	in_size = min_t(size_t, in_len, sizeof(cmd));
1192	if (copy_from_user(&cmd, inbuf, in_size))
1193		return -EFAULT;
1194
1195	ctx = ucma_get_ctx_dev(file, cmd.id);
1196	if (IS_ERR(ctx))
1197		return PTR_ERR(ctx);
1198
1199	if (offsetofend(typeof(cmd), ece) <= in_size) {
1200		ece.vendor_id = cmd.ece.vendor_id;
1201		ece.attr_mod = cmd.ece.attr_mod;
1202	}
1203
1204	if (cmd.conn_param.valid) {
1205		ucma_copy_conn_param(ctx->cm_id, &conn_param, &cmd.conn_param);
1206		mutex_lock(&ctx->mutex);
1207		rdma_lock_handler(ctx->cm_id);
1208		ret = rdma_accept_ece(ctx->cm_id, &conn_param, &ece);
1209		if (!ret) {
1210			/* The uid must be set atomically with the handler */
1211			ctx->uid = cmd.uid;
1212		}
1213		rdma_unlock_handler(ctx->cm_id);
1214		mutex_unlock(&ctx->mutex);
1215	} else {
1216		mutex_lock(&ctx->mutex);
1217		rdma_lock_handler(ctx->cm_id);
1218		ret = rdma_accept_ece(ctx->cm_id, NULL, &ece);
1219		rdma_unlock_handler(ctx->cm_id);
1220		mutex_unlock(&ctx->mutex);
1221	}
1222	ucma_put_ctx(ctx);
1223	return ret;
1224}
1225
1226static ssize_t ucma_reject(struct ucma_file *file, const char __user *inbuf,
1227			   int in_len, int out_len)
1228{
1229	struct rdma_ucm_reject cmd;
1230	struct ucma_context *ctx;
1231	int ret;
1232
1233	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
1234		return -EFAULT;
1235
1236	if (!cmd.reason)
1237		cmd.reason = IB_CM_REJ_CONSUMER_DEFINED;
1238
1239	switch (cmd.reason) {
1240	case IB_CM_REJ_CONSUMER_DEFINED:
1241	case IB_CM_REJ_VENDOR_OPTION_NOT_SUPPORTED:
1242		break;
1243	default:
1244		return -EINVAL;
1245	}
1246
1247	ctx = ucma_get_ctx_dev(file, cmd.id);
1248	if (IS_ERR(ctx))
1249		return PTR_ERR(ctx);
1250
1251	mutex_lock(&ctx->mutex);
1252	ret = rdma_reject(ctx->cm_id, cmd.private_data, cmd.private_data_len,
1253			  cmd.reason);
1254	mutex_unlock(&ctx->mutex);
1255	ucma_put_ctx(ctx);
1256	return ret;
1257}
1258
1259static ssize_t ucma_disconnect(struct ucma_file *file, const char __user *inbuf,
1260			       int in_len, int out_len)
1261{
1262	struct rdma_ucm_disconnect cmd;
1263	struct ucma_context *ctx;
1264	int ret;
1265
1266	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
1267		return -EFAULT;
1268
1269	ctx = ucma_get_ctx_dev(file, cmd.id);
1270	if (IS_ERR(ctx))
1271		return PTR_ERR(ctx);
1272
1273	mutex_lock(&ctx->mutex);
1274	ret = rdma_disconnect(ctx->cm_id);
1275	mutex_unlock(&ctx->mutex);
1276	ucma_put_ctx(ctx);
1277	return ret;
1278}
1279
1280static ssize_t ucma_init_qp_attr(struct ucma_file *file,
1281				 const char __user *inbuf,
1282				 int in_len, int out_len)
1283{
1284	struct rdma_ucm_init_qp_attr cmd;
1285	struct ib_uverbs_qp_attr resp;
1286	struct ucma_context *ctx;
1287	struct ib_qp_attr qp_attr;
1288	int ret;
1289
1290	if (out_len < sizeof(resp))
1291		return -ENOSPC;
1292
1293	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
1294		return -EFAULT;
1295
1296	if (cmd.qp_state > IB_QPS_ERR)
1297		return -EINVAL;
1298
1299	ctx = ucma_get_ctx_dev(file, cmd.id);
1300	if (IS_ERR(ctx))
1301		return PTR_ERR(ctx);
1302
1303	resp.qp_attr_mask = 0;
1304	memset(&qp_attr, 0, sizeof qp_attr);
1305	qp_attr.qp_state = cmd.qp_state;
1306	mutex_lock(&ctx->mutex);
1307	ret = rdma_init_qp_attr(ctx->cm_id, &qp_attr, &resp.qp_attr_mask);
1308	mutex_unlock(&ctx->mutex);
1309	if (ret)
1310		goto out;
1311
1312	ib_copy_qp_attr_to_user(ctx->cm_id->device, &resp, &qp_attr);
1313	if (copy_to_user(u64_to_user_ptr(cmd.response),
1314			 &resp, sizeof(resp)))
1315		ret = -EFAULT;
1316
1317out:
1318	ucma_put_ctx(ctx);
1319	return ret;
1320}
1321
1322static int ucma_set_option_id(struct ucma_context *ctx, int optname,
1323			      void *optval, size_t optlen)
1324{
1325	int ret = 0;
1326
1327	switch (optname) {
1328	case RDMA_OPTION_ID_TOS:
1329		if (optlen != sizeof(u8)) {
1330			ret = -EINVAL;
1331			break;
1332		}
1333		rdma_set_service_type(ctx->cm_id, *((u8 *) optval));
1334		break;
1335	case RDMA_OPTION_ID_REUSEADDR:
1336		if (optlen != sizeof(int)) {
1337			ret = -EINVAL;
1338			break;
1339		}
1340		ret = rdma_set_reuseaddr(ctx->cm_id, *((int *) optval) ? 1 : 0);
1341		break;
1342	case RDMA_OPTION_ID_AFONLY:
1343		if (optlen != sizeof(int)) {
1344			ret = -EINVAL;
1345			break;
1346		}
1347		ret = rdma_set_afonly(ctx->cm_id, *((int *) optval) ? 1 : 0);
1348		break;
1349	case RDMA_OPTION_ID_ACK_TIMEOUT:
1350		if (optlen != sizeof(u8)) {
1351			ret = -EINVAL;
1352			break;
1353		}
1354		ret = rdma_set_ack_timeout(ctx->cm_id, *((u8 *)optval));
1355		break;
1356	default:
1357		ret = -ENOSYS;
1358	}
1359
1360	return ret;
1361}
1362
1363static int ucma_set_ib_path(struct ucma_context *ctx,
1364			    struct ib_path_rec_data *path_data, size_t optlen)
1365{
1366	struct sa_path_rec sa_path;
1367	struct rdma_cm_event event;
1368	int ret;
1369
1370	if (optlen % sizeof(*path_data))
1371		return -EINVAL;
1372
1373	for (; optlen; optlen -= sizeof(*path_data), path_data++) {
1374		if (path_data->flags == (IB_PATH_GMP | IB_PATH_PRIMARY |
1375					 IB_PATH_BIDIRECTIONAL))
1376			break;
1377	}
1378
1379	if (!optlen)
1380		return -EINVAL;
1381
1382	if (!ctx->cm_id->device)
1383		return -EINVAL;
1384
1385	memset(&sa_path, 0, sizeof(sa_path));
1386
1387	sa_path.rec_type = SA_PATH_REC_TYPE_IB;
1388	ib_sa_unpack_path(path_data->path_rec, &sa_path);
1389
1390	if (rdma_cap_opa_ah(ctx->cm_id->device, ctx->cm_id->port_num)) {
1391		struct sa_path_rec opa;
1392
1393		sa_convert_path_ib_to_opa(&opa, &sa_path);
1394		mutex_lock(&ctx->mutex);
1395		ret = rdma_set_ib_path(ctx->cm_id, &opa);
1396		mutex_unlock(&ctx->mutex);
1397	} else {
1398		mutex_lock(&ctx->mutex);
1399		ret = rdma_set_ib_path(ctx->cm_id, &sa_path);
1400		mutex_unlock(&ctx->mutex);
1401	}
1402	if (ret)
1403		return ret;
1404
1405	memset(&event, 0, sizeof event);
1406	event.event = RDMA_CM_EVENT_ROUTE_RESOLVED;
1407	return ucma_event_handler(ctx->cm_id, &event);
1408}
1409
1410static int ucma_set_option_ib(struct ucma_context *ctx, int optname,
1411			      void *optval, size_t optlen)
1412{
1413	int ret;
1414
1415	switch (optname) {
1416	case RDMA_OPTION_IB_PATH:
1417		ret = ucma_set_ib_path(ctx, optval, optlen);
1418		break;
1419	default:
1420		ret = -ENOSYS;
1421	}
1422
1423	return ret;
1424}
1425
1426static int ucma_set_option_level(struct ucma_context *ctx, int level,
1427				 int optname, void *optval, size_t optlen)
1428{
1429	int ret;
1430
1431	switch (level) {
1432	case RDMA_OPTION_ID:
1433		mutex_lock(&ctx->mutex);
1434		ret = ucma_set_option_id(ctx, optname, optval, optlen);
1435		mutex_unlock(&ctx->mutex);
1436		break;
1437	case RDMA_OPTION_IB:
1438		ret = ucma_set_option_ib(ctx, optname, optval, optlen);
1439		break;
1440	default:
1441		ret = -ENOSYS;
1442	}
1443
1444	return ret;
1445}
1446
1447static ssize_t ucma_set_option(struct ucma_file *file, const char __user *inbuf,
1448			       int in_len, int out_len)
1449{
1450	struct rdma_ucm_set_option cmd;
1451	struct ucma_context *ctx;
1452	void *optval;
1453	int ret;
1454
1455	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
1456		return -EFAULT;
1457
1458	if (unlikely(cmd.optlen > KMALLOC_MAX_SIZE))
1459		return -EINVAL;
1460
1461	ctx = ucma_get_ctx(file, cmd.id);
1462	if (IS_ERR(ctx))
1463		return PTR_ERR(ctx);
1464
1465	optval = memdup_user(u64_to_user_ptr(cmd.optval),
1466			     cmd.optlen);
1467	if (IS_ERR(optval)) {
1468		ret = PTR_ERR(optval);
1469		goto out;
1470	}
1471
1472	ret = ucma_set_option_level(ctx, cmd.level, cmd.optname, optval,
1473				    cmd.optlen);
1474	kfree(optval);
1475
1476out:
1477	ucma_put_ctx(ctx);
1478	return ret;
1479}
1480
1481static ssize_t ucma_notify(struct ucma_file *file, const char __user *inbuf,
1482			   int in_len, int out_len)
1483{
1484	struct rdma_ucm_notify cmd;
1485	struct ucma_context *ctx;
1486	int ret = -EINVAL;
1487
1488	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
1489		return -EFAULT;
1490
1491	ctx = ucma_get_ctx(file, cmd.id);
1492	if (IS_ERR(ctx))
1493		return PTR_ERR(ctx);
1494
1495	mutex_lock(&ctx->mutex);
1496	if (ctx->cm_id->device)
1497		ret = rdma_notify(ctx->cm_id, (enum ib_event_type)cmd.event);
1498	mutex_unlock(&ctx->mutex);
1499
1500	ucma_put_ctx(ctx);
1501	return ret;
1502}
1503
1504static ssize_t ucma_process_join(struct ucma_file *file,
1505				 struct rdma_ucm_join_mcast *cmd,  int out_len)
1506{
1507	struct rdma_ucm_create_id_resp resp;
1508	struct ucma_context *ctx;
1509	struct ucma_multicast *mc;
1510	struct sockaddr *addr;
1511	int ret;
1512	u8 join_state;
1513
1514	if (out_len < sizeof(resp))
1515		return -ENOSPC;
1516
1517	addr = (struct sockaddr *) &cmd->addr;
1518	if (cmd->addr_size != rdma_addr_size(addr))
1519		return -EINVAL;
1520
1521	if (cmd->join_flags == RDMA_MC_JOIN_FLAG_FULLMEMBER)
1522		join_state = BIT(FULLMEMBER_JOIN);
1523	else if (cmd->join_flags == RDMA_MC_JOIN_FLAG_SENDONLY_FULLMEMBER)
1524		join_state = BIT(SENDONLY_FULLMEMBER_JOIN);
1525	else
1526		return -EINVAL;
1527
1528	ctx = ucma_get_ctx_dev(file, cmd->id);
1529	if (IS_ERR(ctx))
1530		return PTR_ERR(ctx);
1531
1532	mc = kzalloc(sizeof(*mc), GFP_KERNEL);
1533	if (!mc) {
1534		ret = -ENOMEM;
1535		goto err_put_ctx;
1536	}
1537
1538	mc->ctx = ctx;
1539	mc->join_state = join_state;
1540	mc->uid = cmd->uid;
1541	memcpy(&mc->addr, addr, cmd->addr_size);
1542
1543	xa_lock(&multicast_table);
1544	if (__xa_alloc(&multicast_table, &mc->id, NULL, xa_limit_32b,
1545		     GFP_KERNEL)) {
1546		ret = -ENOMEM;
1547		goto err_free_mc;
1548	}
1549
1550	list_add_tail(&mc->list, &ctx->mc_list);
1551	xa_unlock(&multicast_table);
1552
1553	mutex_lock(&ctx->mutex);
1554	ret = rdma_join_multicast(ctx->cm_id, (struct sockaddr *)&mc->addr,
1555				  join_state, mc);
1556	mutex_unlock(&ctx->mutex);
1557	if (ret)
1558		goto err_xa_erase;
1559
1560	resp.id = mc->id;
1561	if (copy_to_user(u64_to_user_ptr(cmd->response),
1562			 &resp, sizeof(resp))) {
1563		ret = -EFAULT;
1564		goto err_leave_multicast;
1565	}
1566
1567	xa_store(&multicast_table, mc->id, mc, 0);
1568
1569	ucma_put_ctx(ctx);
1570	return 0;
1571
1572err_leave_multicast:
1573	mutex_lock(&ctx->mutex);
1574	rdma_leave_multicast(ctx->cm_id, (struct sockaddr *) &mc->addr);
1575	mutex_unlock(&ctx->mutex);
1576	ucma_cleanup_mc_events(mc);
1577err_xa_erase:
1578	xa_lock(&multicast_table);
1579	list_del(&mc->list);
1580	__xa_erase(&multicast_table, mc->id);
1581err_free_mc:
1582	xa_unlock(&multicast_table);
1583	kfree(mc);
1584err_put_ctx:
1585	ucma_put_ctx(ctx);
1586	return ret;
1587}
1588
1589static ssize_t ucma_join_ip_multicast(struct ucma_file *file,
1590				      const char __user *inbuf,
1591				      int in_len, int out_len)
1592{
1593	struct rdma_ucm_join_ip_mcast cmd;
1594	struct rdma_ucm_join_mcast join_cmd;
1595
1596	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
1597		return -EFAULT;
1598
1599	join_cmd.response = cmd.response;
1600	join_cmd.uid = cmd.uid;
1601	join_cmd.id = cmd.id;
1602	join_cmd.addr_size = rdma_addr_size_in6(&cmd.addr);
1603	if (!join_cmd.addr_size)
1604		return -EINVAL;
1605
1606	join_cmd.join_flags = RDMA_MC_JOIN_FLAG_FULLMEMBER;
1607	memcpy(&join_cmd.addr, &cmd.addr, join_cmd.addr_size);
1608
1609	return ucma_process_join(file, &join_cmd, out_len);
1610}
1611
1612static ssize_t ucma_join_multicast(struct ucma_file *file,
1613				   const char __user *inbuf,
1614				   int in_len, int out_len)
1615{
1616	struct rdma_ucm_join_mcast cmd;
1617
1618	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
1619		return -EFAULT;
1620
1621	if (!rdma_addr_size_kss(&cmd.addr))
1622		return -EINVAL;
1623
1624	return ucma_process_join(file, &cmd, out_len);
1625}
1626
1627static ssize_t ucma_leave_multicast(struct ucma_file *file,
1628				    const char __user *inbuf,
1629				    int in_len, int out_len)
1630{
1631	struct rdma_ucm_destroy_id cmd;
1632	struct rdma_ucm_destroy_id_resp resp;
1633	struct ucma_multicast *mc;
1634	int ret = 0;
1635
1636	if (out_len < sizeof(resp))
1637		return -ENOSPC;
1638
1639	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
1640		return -EFAULT;
1641
1642	xa_lock(&multicast_table);
1643	mc = xa_load(&multicast_table, cmd.id);
1644	if (!mc)
1645		mc = ERR_PTR(-ENOENT);
1646	else if (READ_ONCE(mc->ctx->file) != file)
1647		mc = ERR_PTR(-EINVAL);
1648	else if (!refcount_inc_not_zero(&mc->ctx->ref))
1649		mc = ERR_PTR(-ENXIO);
1650
1651	if (IS_ERR(mc)) {
1652		xa_unlock(&multicast_table);
1653		ret = PTR_ERR(mc);
1654		goto out;
1655	}
1656
1657	list_del(&mc->list);
1658	__xa_erase(&multicast_table, mc->id);
1659	xa_unlock(&multicast_table);
1660
1661	mutex_lock(&mc->ctx->mutex);
1662	rdma_leave_multicast(mc->ctx->cm_id, (struct sockaddr *) &mc->addr);
1663	mutex_unlock(&mc->ctx->mutex);
1664
1665	ucma_cleanup_mc_events(mc);
1666
1667	ucma_put_ctx(mc->ctx);
1668	resp.events_reported = mc->events_reported;
1669	kfree(mc);
1670
1671	if (copy_to_user(u64_to_user_ptr(cmd.response),
1672			 &resp, sizeof(resp)))
1673		ret = -EFAULT;
1674out:
1675	return ret;
1676}
1677
1678static ssize_t ucma_migrate_id(struct ucma_file *new_file,
1679			       const char __user *inbuf,
1680			       int in_len, int out_len)
1681{
1682	struct rdma_ucm_migrate_id cmd;
1683	struct rdma_ucm_migrate_resp resp;
1684	struct ucma_event *uevent, *tmp;
1685	struct ucma_context *ctx;
1686	LIST_HEAD(event_list);
1687	struct ucma_file *cur_file;
1688	int ret = 0;
1689
1690	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
1691		return -EFAULT;
1692
1693	/* Get current fd to protect against it being closed */
1694	CLASS(fd, f)(cmd.fd);
1695	if (fd_empty(f))
1696		return -ENOENT;
1697	if (fd_file(f)->f_op != &ucma_fops)
1698		return -EINVAL;
1699	cur_file = fd_file(f)->private_data;
1700
1701	/* Validate current fd and prevent destruction of id. */
1702	ctx = ucma_get_ctx(cur_file, cmd.id);
1703	if (IS_ERR(ctx))
1704		return PTR_ERR(ctx);
1705
1706	rdma_lock_handler(ctx->cm_id);
1707	/*
1708	 * ctx->file can only be changed under the handler & xa_lock. xa_load()
1709	 * must be checked again to ensure the ctx hasn't begun destruction
1710	 * since the ucma_get_ctx().
1711	 */
1712	xa_lock(&ctx_table);
1713	if (_ucma_find_context(cmd.id, cur_file) != ctx) {
1714		xa_unlock(&ctx_table);
1715		ret = -ENOENT;
1716		goto err_unlock;
1717	}
1718	ctx->file = new_file;
1719	xa_unlock(&ctx_table);
1720
1721	mutex_lock(&cur_file->mut);
1722	list_del(&ctx->list);
1723	/*
1724	 * At this point lock_handler() prevents addition of new uevents for
1725	 * this ctx.
1726	 */
1727	list_for_each_entry_safe(uevent, tmp, &cur_file->event_list, list)
1728		if (uevent->ctx == ctx)
1729			list_move_tail(&uevent->list, &event_list);
1730	resp.events_reported = ctx->events_reported;
1731	mutex_unlock(&cur_file->mut);
1732
1733	mutex_lock(&new_file->mut);
1734	list_add_tail(&ctx->list, &new_file->ctx_list);
1735	list_splice_tail(&event_list, &new_file->event_list);
1736	mutex_unlock(&new_file->mut);
1737
1738	if (copy_to_user(u64_to_user_ptr(cmd.response),
1739			 &resp, sizeof(resp)))
1740		ret = -EFAULT;
1741
1742err_unlock:
1743	rdma_unlock_handler(ctx->cm_id);
1744	ucma_put_ctx(ctx);
1745	return ret;
1746}
1747
1748static ssize_t ucma_write_cm_event(struct ucma_file *file,
1749				   const char __user *inbuf, int in_len,
1750				   int out_len)
1751{
1752	struct rdma_ucm_write_cm_event cmd;
1753	struct rdma_cm_event event = {};
1754	struct ucma_event *uevent;
1755	struct ucma_context *ctx;
1756	int ret = 0;
1757
1758	if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
1759		return -EFAULT;
1760
1761	if ((cmd.event != RDMA_CM_EVENT_USER) &&
1762	    (cmd.event != RDMA_CM_EVENT_INTERNAL))
1763		return -EINVAL;
1764
1765	ctx = ucma_get_ctx(file, cmd.id);
1766	if (IS_ERR(ctx))
1767		return PTR_ERR(ctx);
1768
1769	event.event = cmd.event;
1770	event.status = cmd.status;
1771	event.param.arg = cmd.param.arg;
1772
1773	uevent = kzalloc(sizeof(*uevent), GFP_KERNEL);
1774	if (!uevent) {
1775		ret = -ENOMEM;
1776		goto out;
1777	}
1778
1779	uevent->ctx = ctx;
1780	uevent->resp.uid = ctx->uid;
1781	uevent->resp.id = ctx->id;
1782	uevent->resp.event = event.event;
1783	uevent->resp.status = event.status;
1784	memcpy(uevent->resp.param.arg32, &event.param.arg,
1785	       sizeof(event.param.arg));
1786
1787	mutex_lock(&ctx->file->mut);
1788	list_add_tail(&uevent->list, &ctx->file->event_list);
1789	mutex_unlock(&ctx->file->mut);
1790	wake_up_interruptible(&ctx->file->poll_wait);
1791
1792out:
1793	ucma_put_ctx(ctx);
1794	return ret;
1795}
1796
1797static ssize_t (*ucma_cmd_table[])(struct ucma_file *file,
1798				   const char __user *inbuf,
1799				   int in_len, int out_len) = {
1800	[RDMA_USER_CM_CMD_CREATE_ID] 	 = ucma_create_id,
1801	[RDMA_USER_CM_CMD_DESTROY_ID]	 = ucma_destroy_id,
1802	[RDMA_USER_CM_CMD_BIND_IP]	 = ucma_bind_ip,
1803	[RDMA_USER_CM_CMD_RESOLVE_IP]	 = ucma_resolve_ip,
1804	[RDMA_USER_CM_CMD_RESOLVE_ROUTE] = ucma_resolve_route,
1805	[RDMA_USER_CM_CMD_QUERY_ROUTE]	 = ucma_query_route,
1806	[RDMA_USER_CM_CMD_CONNECT]	 = ucma_connect,
1807	[RDMA_USER_CM_CMD_LISTEN]	 = ucma_listen,
1808	[RDMA_USER_CM_CMD_ACCEPT]	 = ucma_accept,
1809	[RDMA_USER_CM_CMD_REJECT]	 = ucma_reject,
1810	[RDMA_USER_CM_CMD_DISCONNECT]	 = ucma_disconnect,
1811	[RDMA_USER_CM_CMD_INIT_QP_ATTR]	 = ucma_init_qp_attr,
1812	[RDMA_USER_CM_CMD_GET_EVENT]	 = ucma_get_event,
1813	[RDMA_USER_CM_CMD_GET_OPTION]	 = NULL,
1814	[RDMA_USER_CM_CMD_SET_OPTION]	 = ucma_set_option,
1815	[RDMA_USER_CM_CMD_NOTIFY]	 = ucma_notify,
1816	[RDMA_USER_CM_CMD_JOIN_IP_MCAST] = ucma_join_ip_multicast,
1817	[RDMA_USER_CM_CMD_LEAVE_MCAST]	 = ucma_leave_multicast,
1818	[RDMA_USER_CM_CMD_MIGRATE_ID]	 = ucma_migrate_id,
1819	[RDMA_USER_CM_CMD_QUERY]	 = ucma_query,
1820	[RDMA_USER_CM_CMD_BIND]		 = ucma_bind,
1821	[RDMA_USER_CM_CMD_RESOLVE_ADDR]	 = ucma_resolve_addr,
1822	[RDMA_USER_CM_CMD_JOIN_MCAST]	 = ucma_join_multicast,
1823	[RDMA_USER_CM_CMD_RESOLVE_IB_SERVICE] = ucma_resolve_ib_service,
1824	[RDMA_USER_CM_CMD_WRITE_CM_EVENT] = ucma_write_cm_event,
1825};
1826
1827static ssize_t ucma_write(struct file *filp, const char __user *buf,
1828			  size_t len, loff_t *pos)
1829{
1830	struct ucma_file *file = filp->private_data;
1831	struct rdma_ucm_cmd_hdr hdr;
1832	ssize_t ret;
1833
1834	if (!ib_safe_file_access(filp)) {
1835		pr_err_once("%s: process %d (%s) changed security contexts after opening file descriptor, this is not allowed.\n",
1836			    __func__, task_tgid_vnr(current), current->comm);
1837		return -EACCES;
1838	}
1839
1840	if (len < sizeof(hdr))
1841		return -EINVAL;
1842
1843	if (copy_from_user(&hdr, buf, sizeof(hdr)))
1844		return -EFAULT;
1845
1846	if (hdr.cmd >= ARRAY_SIZE(ucma_cmd_table))
1847		return -EINVAL;
1848	hdr.cmd = array_index_nospec(hdr.cmd, ARRAY_SIZE(ucma_cmd_table));
1849
1850	if (hdr.in + sizeof(hdr) > len)
1851		return -EINVAL;
1852
1853	if (!ucma_cmd_table[hdr.cmd])
1854		return -ENOSYS;
1855
1856	ret = ucma_cmd_table[hdr.cmd](file, buf + sizeof(hdr), hdr.in, hdr.out);
1857	if (!ret)
1858		ret = len;
1859
1860	return ret;
1861}
1862
1863static __poll_t ucma_poll(struct file *filp, struct poll_table_struct *wait)
1864{
1865	struct ucma_file *file = filp->private_data;
1866	__poll_t mask = 0;
1867
1868	poll_wait(filp, &file->poll_wait, wait);
1869
1870	if (!list_empty(&file->event_list))
1871		mask = EPOLLIN | EPOLLRDNORM;
1872
1873	return mask;
1874}
1875
1876/*
1877 * ucma_open() does not need the BKL:
1878 *
1879 *  - no global state is referred to;
1880 *  - there is no ioctl method to race against;
1881 *  - no further module initialization is required for open to work
1882 *    after the device is registered.
1883 */
1884static int ucma_open(struct inode *inode, struct file *filp)
1885{
1886	struct ucma_file *file;
1887
1888	file = kmalloc(sizeof *file, GFP_KERNEL);
1889	if (!file)
1890		return -ENOMEM;
1891
1892	INIT_LIST_HEAD(&file->event_list);
1893	INIT_LIST_HEAD(&file->ctx_list);
1894	init_waitqueue_head(&file->poll_wait);
1895	mutex_init(&file->mut);
1896
1897	filp->private_data = file;
1898	file->filp = filp;
1899
1900	return stream_open(inode, filp);
1901}
1902
1903static int ucma_close(struct inode *inode, struct file *filp)
1904{
1905	struct ucma_file *file = filp->private_data;
1906
1907	/*
1908	 * All paths that touch ctx_list or ctx_list starting from write() are
1909	 * prevented by this being a FD release function. The list_add_tail() in
1910	 * ucma_connect_event_handler() can run concurrently, however it only
1911	 * adds to the list *after* a listening ID. By only reading the first of
1912	 * the list, and relying on ucma_destroy_private_ctx() to block
1913	 * ucma_connect_event_handler(), no additional locking is needed.
1914	 */
1915	while (!list_empty(&file->ctx_list)) {
1916		struct ucma_context *ctx = list_first_entry(
1917			&file->ctx_list, struct ucma_context, list);
1918
1919		WARN_ON(xa_cmpxchg(&ctx_table, ctx->id, ctx, XA_ZERO_ENTRY,
1920				   GFP_KERNEL) != ctx);
1921		ucma_destroy_private_ctx(ctx);
1922	}
1923	kfree(file);
1924	return 0;
1925}
1926
1927static const struct file_operations ucma_fops = {
1928	.owner 	 = THIS_MODULE,
1929	.open 	 = ucma_open,
1930	.release = ucma_close,
1931	.write	 = ucma_write,
1932	.poll    = ucma_poll,
1933};
1934
1935static struct miscdevice ucma_misc = {
1936	.minor		= MISC_DYNAMIC_MINOR,
1937	.name		= "rdma_cm",
1938	.nodename	= "infiniband/rdma_cm",
1939	.mode		= 0666,
1940	.fops		= &ucma_fops,
1941};
1942
1943static int ucma_get_global_nl_info(struct ib_client_nl_info *res)
1944{
1945	res->abi = RDMA_USER_CM_ABI_VERSION;
1946	res->cdev = ucma_misc.this_device;
1947	return 0;
1948}
1949
1950static struct ib_client rdma_cma_client = {
1951	.name = "rdma_cm",
1952	.get_global_nl_info = ucma_get_global_nl_info,
1953};
1954MODULE_ALIAS_RDMA_CLIENT("rdma_cm");
1955
1956static ssize_t abi_version_show(struct device *dev,
1957				struct device_attribute *attr, char *buf)
1958{
1959	return sysfs_emit(buf, "%d\n", RDMA_USER_CM_ABI_VERSION);
1960}
1961static DEVICE_ATTR_RO(abi_version);
1962
1963static int __init ucma_init(void)
1964{
1965	int ret;
1966
1967	ret = misc_register(&ucma_misc);
1968	if (ret)
1969		return ret;
1970
1971	ret = device_create_file(ucma_misc.this_device, &dev_attr_abi_version);
1972	if (ret) {
1973		pr_err("rdma_ucm: couldn't create abi_version attr\n");
1974		goto err1;
1975	}
1976
1977	ucma_ctl_table_hdr = register_net_sysctl(&init_net, "net/rdma_ucm", ucma_ctl_table);
1978	if (!ucma_ctl_table_hdr) {
1979		pr_err("rdma_ucm: couldn't register sysctl paths\n");
1980		ret = -ENOMEM;
1981		goto err2;
1982	}
1983
1984	ret = ib_register_client(&rdma_cma_client);
1985	if (ret)
1986		goto err3;
1987
1988	return 0;
1989err3:
1990	unregister_net_sysctl_table(ucma_ctl_table_hdr);
1991err2:
1992	device_remove_file(ucma_misc.this_device, &dev_attr_abi_version);
1993err1:
1994	misc_deregister(&ucma_misc);
1995	return ret;
1996}
1997
1998static void __exit ucma_cleanup(void)
1999{
2000	ib_unregister_client(&rdma_cma_client);
2001	unregister_net_sysctl_table(ucma_ctl_table_hdr);
2002	device_remove_file(ucma_misc.this_device, &dev_attr_abi_version);
2003	misc_deregister(&ucma_misc);
2004}
2005
2006module_init(ucma_init);
2007module_exit(ucma_cleanup);