xref: /linux/drivers/infiniband/core/user_mad.c (revision 4b660dbd9ee2059850fd30e0df420ca7a38a1856)
1 /*
2  * Copyright (c) 2004 Topspin Communications.  All rights reserved.
3  * Copyright (c) 2005 Voltaire, Inc. All rights reserved.
4  * Copyright (c) 2005 Sun Microsystems, Inc. All rights reserved.
5  * Copyright (c) 2008 Cisco. All rights reserved.
6  *
7  * This software is available to you under a choice of one of two
8  * licenses.  You may choose to be licensed under the terms of the GNU
9  * General Public License (GPL) Version 2, available from the file
10  * COPYING in the main directory of this source tree, or the
11  * OpenIB.org BSD license below:
12  *
13  *     Redistribution and use in source and binary forms, with or
14  *     without modification, are permitted provided that the following
15  *     conditions are met:
16  *
17  *      - Redistributions of source code must retain the above
18  *        copyright notice, this list of conditions and the following
19  *        disclaimer.
20  *
21  *      - Redistributions in binary form must reproduce the above
22  *        copyright notice, this list of conditions and the following
23  *        disclaimer in the documentation and/or other materials
24  *        provided with the distribution.
25  *
26  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
27  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
28  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
29  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
30  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
31  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
32  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
33  * SOFTWARE.
34  */
35 
36 #define pr_fmt(fmt) "user_mad: " fmt
37 
38 #include <linux/module.h>
39 #include <linux/init.h>
40 #include <linux/device.h>
41 #include <linux/err.h>
42 #include <linux/fs.h>
43 #include <linux/cdev.h>
44 #include <linux/dma-mapping.h>
45 #include <linux/poll.h>
46 #include <linux/mutex.h>
47 #include <linux/kref.h>
48 #include <linux/compat.h>
49 #include <linux/sched.h>
50 #include <linux/semaphore.h>
51 #include <linux/slab.h>
52 #include <linux/nospec.h>
53 
54 #include <linux/uaccess.h>
55 
56 #include <rdma/ib_mad.h>
57 #include <rdma/ib_user_mad.h>
58 #include <rdma/rdma_netlink.h>
59 
60 #include "core_priv.h"
61 
62 MODULE_AUTHOR("Roland Dreier");
63 MODULE_DESCRIPTION("InfiniBand userspace MAD packet access");
64 MODULE_LICENSE("Dual BSD/GPL");
65 
66 enum {
67 	IB_UMAD_MAX_PORTS  = RDMA_MAX_PORTS,
68 	IB_UMAD_MAX_AGENTS = 32,
69 
70 	IB_UMAD_MAJOR      = 231,
71 	IB_UMAD_MINOR_BASE = 0,
72 	IB_UMAD_NUM_FIXED_MINOR = 64,
73 	IB_UMAD_NUM_DYNAMIC_MINOR = IB_UMAD_MAX_PORTS - IB_UMAD_NUM_FIXED_MINOR,
74 	IB_ISSM_MINOR_BASE        = IB_UMAD_NUM_FIXED_MINOR,
75 };
76 
77 /*
78  * Our lifetime rules for these structs are the following:
79  * device special file is opened, we take a reference on the
80  * ib_umad_port's struct ib_umad_device. We drop these
81  * references in the corresponding close().
82  *
83  * In addition to references coming from open character devices, there
84  * is one more reference to each ib_umad_device representing the
85  * module's reference taken when allocating the ib_umad_device in
86  * ib_umad_add_one().
87  *
88  * When destroying an ib_umad_device, we drop the module's reference.
89  */
90 
91 struct ib_umad_port {
92 	struct cdev           cdev;
93 	struct device	      dev;
94 	struct cdev           sm_cdev;
95 	struct device	      sm_dev;
96 	struct semaphore       sm_sem;
97 
98 	struct mutex	       file_mutex;
99 	struct list_head       file_list;
100 
101 	struct ib_device      *ib_dev;
102 	struct ib_umad_device *umad_dev;
103 	int                    dev_num;
104 	u32                     port_num;
105 };
106 
107 struct ib_umad_device {
108 	struct kref kref;
109 	struct ib_umad_port ports[];
110 };
111 
112 struct ib_umad_file {
113 	struct mutex		mutex;
114 	struct ib_umad_port    *port;
115 	struct list_head	recv_list;
116 	struct list_head	send_list;
117 	struct list_head	port_list;
118 	spinlock_t		send_lock;
119 	wait_queue_head_t	recv_wait;
120 	struct ib_mad_agent    *agent[IB_UMAD_MAX_AGENTS];
121 	int			agents_dead;
122 	u8			use_pkey_index;
123 	u8			already_used;
124 };
125 
126 struct ib_umad_packet {
127 	struct ib_mad_send_buf *msg;
128 	struct ib_mad_recv_wc  *recv_wc;
129 	struct list_head   list;
130 	int		   length;
131 	struct ib_user_mad mad;
132 };
133 
134 struct ib_rmpp_mad_hdr {
135 	struct ib_mad_hdr	mad_hdr;
136 	struct ib_rmpp_hdr      rmpp_hdr;
137 } __packed;
138 
139 #define CREATE_TRACE_POINTS
140 #include <trace/events/ib_umad.h>
141 
142 static const dev_t base_umad_dev = MKDEV(IB_UMAD_MAJOR, IB_UMAD_MINOR_BASE);
143 static const dev_t base_issm_dev = MKDEV(IB_UMAD_MAJOR, IB_UMAD_MINOR_BASE) +
144 				   IB_UMAD_NUM_FIXED_MINOR;
145 static dev_t dynamic_umad_dev;
146 static dev_t dynamic_issm_dev;
147 
148 static DEFINE_IDA(umad_ida);
149 
150 static int ib_umad_add_one(struct ib_device *device);
151 static void ib_umad_remove_one(struct ib_device *device, void *client_data);
152 
153 static void ib_umad_dev_free(struct kref *kref)
154 {
155 	struct ib_umad_device *dev =
156 		container_of(kref, struct ib_umad_device, kref);
157 
158 	kfree(dev);
159 }
160 
161 static void ib_umad_dev_get(struct ib_umad_device *dev)
162 {
163 	kref_get(&dev->kref);
164 }
165 
166 static void ib_umad_dev_put(struct ib_umad_device *dev)
167 {
168 	kref_put(&dev->kref, ib_umad_dev_free);
169 }
170 
171 static int hdr_size(struct ib_umad_file *file)
172 {
173 	return file->use_pkey_index ? sizeof(struct ib_user_mad_hdr) :
174 				      sizeof(struct ib_user_mad_hdr_old);
175 }
176 
177 /* caller must hold file->mutex */
178 static struct ib_mad_agent *__get_agent(struct ib_umad_file *file, int id)
179 {
180 	return file->agents_dead ? NULL : file->agent[id];
181 }
182 
183 static int queue_packet(struct ib_umad_file *file,
184 			struct ib_mad_agent *agent,
185 			struct ib_umad_packet *packet)
186 {
187 	int ret = 1;
188 
189 	mutex_lock(&file->mutex);
190 
191 	for (packet->mad.hdr.id = 0;
192 	     packet->mad.hdr.id < IB_UMAD_MAX_AGENTS;
193 	     packet->mad.hdr.id++)
194 		if (agent == __get_agent(file, packet->mad.hdr.id)) {
195 			list_add_tail(&packet->list, &file->recv_list);
196 			wake_up_interruptible(&file->recv_wait);
197 			ret = 0;
198 			break;
199 		}
200 
201 	mutex_unlock(&file->mutex);
202 
203 	return ret;
204 }
205 
206 static void dequeue_send(struct ib_umad_file *file,
207 			 struct ib_umad_packet *packet)
208 {
209 	spin_lock_irq(&file->send_lock);
210 	list_del(&packet->list);
211 	spin_unlock_irq(&file->send_lock);
212 }
213 
214 static void send_handler(struct ib_mad_agent *agent,
215 			 struct ib_mad_send_wc *send_wc)
216 {
217 	struct ib_umad_file *file = agent->context;
218 	struct ib_umad_packet *packet = send_wc->send_buf->context[0];
219 
220 	dequeue_send(file, packet);
221 	rdma_destroy_ah(packet->msg->ah, RDMA_DESTROY_AH_SLEEPABLE);
222 	ib_free_send_mad(packet->msg);
223 
224 	if (send_wc->status == IB_WC_RESP_TIMEOUT_ERR) {
225 		packet->length = IB_MGMT_MAD_HDR;
226 		packet->mad.hdr.status = ETIMEDOUT;
227 		if (!queue_packet(file, agent, packet))
228 			return;
229 	}
230 	kfree(packet);
231 }
232 
233 static void recv_handler(struct ib_mad_agent *agent,
234 			 struct ib_mad_send_buf *send_buf,
235 			 struct ib_mad_recv_wc *mad_recv_wc)
236 {
237 	struct ib_umad_file *file = agent->context;
238 	struct ib_umad_packet *packet;
239 
240 	if (mad_recv_wc->wc->status != IB_WC_SUCCESS)
241 		goto err1;
242 
243 	packet = kzalloc(sizeof *packet, GFP_KERNEL);
244 	if (!packet)
245 		goto err1;
246 
247 	packet->length = mad_recv_wc->mad_len;
248 	packet->recv_wc = mad_recv_wc;
249 
250 	packet->mad.hdr.status	   = 0;
251 	packet->mad.hdr.length	   = hdr_size(file) + mad_recv_wc->mad_len;
252 	packet->mad.hdr.qpn	   = cpu_to_be32(mad_recv_wc->wc->src_qp);
253 	/*
254 	 * On OPA devices it is okay to lose the upper 16 bits of LID as this
255 	 * information is obtained elsewhere. Mask off the upper 16 bits.
256 	 */
257 	if (rdma_cap_opa_mad(agent->device, agent->port_num))
258 		packet->mad.hdr.lid = ib_lid_be16(0xFFFF &
259 						  mad_recv_wc->wc->slid);
260 	else
261 		packet->mad.hdr.lid = ib_lid_be16(mad_recv_wc->wc->slid);
262 	packet->mad.hdr.sl	   = mad_recv_wc->wc->sl;
263 	packet->mad.hdr.path_bits  = mad_recv_wc->wc->dlid_path_bits;
264 	packet->mad.hdr.pkey_index = mad_recv_wc->wc->pkey_index;
265 	packet->mad.hdr.grh_present = !!(mad_recv_wc->wc->wc_flags & IB_WC_GRH);
266 	if (packet->mad.hdr.grh_present) {
267 		struct rdma_ah_attr ah_attr;
268 		const struct ib_global_route *grh;
269 		int ret;
270 
271 		ret = ib_init_ah_attr_from_wc(agent->device, agent->port_num,
272 					      mad_recv_wc->wc,
273 					      mad_recv_wc->recv_buf.grh,
274 					      &ah_attr);
275 		if (ret)
276 			goto err2;
277 
278 		grh = rdma_ah_read_grh(&ah_attr);
279 		packet->mad.hdr.gid_index = grh->sgid_index;
280 		packet->mad.hdr.hop_limit = grh->hop_limit;
281 		packet->mad.hdr.traffic_class = grh->traffic_class;
282 		memcpy(packet->mad.hdr.gid, &grh->dgid, 16);
283 		packet->mad.hdr.flow_label = cpu_to_be32(grh->flow_label);
284 		rdma_destroy_ah_attr(&ah_attr);
285 	}
286 
287 	if (queue_packet(file, agent, packet))
288 		goto err2;
289 	return;
290 
291 err2:
292 	kfree(packet);
293 err1:
294 	ib_free_recv_mad(mad_recv_wc);
295 }
296 
297 static ssize_t copy_recv_mad(struct ib_umad_file *file, char __user *buf,
298 			     struct ib_umad_packet *packet, size_t count)
299 {
300 	struct ib_mad_recv_buf *recv_buf;
301 	int left, seg_payload, offset, max_seg_payload;
302 	size_t seg_size;
303 
304 	recv_buf = &packet->recv_wc->recv_buf;
305 	seg_size = packet->recv_wc->mad_seg_size;
306 
307 	/* We need enough room to copy the first (or only) MAD segment. */
308 	if ((packet->length <= seg_size &&
309 	     count < hdr_size(file) + packet->length) ||
310 	    (packet->length > seg_size &&
311 	     count < hdr_size(file) + seg_size))
312 		return -EINVAL;
313 
314 	if (copy_to_user(buf, &packet->mad, hdr_size(file)))
315 		return -EFAULT;
316 
317 	buf += hdr_size(file);
318 	seg_payload = min_t(int, packet->length, seg_size);
319 	if (copy_to_user(buf, recv_buf->mad, seg_payload))
320 		return -EFAULT;
321 
322 	if (seg_payload < packet->length) {
323 		/*
324 		 * Multipacket RMPP MAD message. Copy remainder of message.
325 		 * Note that last segment may have a shorter payload.
326 		 */
327 		if (count < hdr_size(file) + packet->length) {
328 			/*
329 			 * The buffer is too small, return the first RMPP segment,
330 			 * which includes the RMPP message length.
331 			 */
332 			return -ENOSPC;
333 		}
334 		offset = ib_get_mad_data_offset(recv_buf->mad->mad_hdr.mgmt_class);
335 		max_seg_payload = seg_size - offset;
336 
337 		for (left = packet->length - seg_payload, buf += seg_payload;
338 		     left; left -= seg_payload, buf += seg_payload) {
339 			recv_buf = container_of(recv_buf->list.next,
340 						struct ib_mad_recv_buf, list);
341 			seg_payload = min(left, max_seg_payload);
342 			if (copy_to_user(buf, ((void *) recv_buf->mad) + offset,
343 					 seg_payload))
344 				return -EFAULT;
345 		}
346 	}
347 
348 	trace_ib_umad_read_recv(file, &packet->mad.hdr, &recv_buf->mad->mad_hdr);
349 
350 	return hdr_size(file) + packet->length;
351 }
352 
353 static ssize_t copy_send_mad(struct ib_umad_file *file, char __user *buf,
354 			     struct ib_umad_packet *packet, size_t count)
355 {
356 	ssize_t size = hdr_size(file) + packet->length;
357 
358 	if (count < size)
359 		return -EINVAL;
360 
361 	if (copy_to_user(buf, &packet->mad, hdr_size(file)))
362 		return -EFAULT;
363 
364 	buf += hdr_size(file);
365 
366 	if (copy_to_user(buf, packet->mad.data, packet->length))
367 		return -EFAULT;
368 
369 	trace_ib_umad_read_send(file, &packet->mad.hdr,
370 				(struct ib_mad_hdr *)&packet->mad.data);
371 
372 	return size;
373 }
374 
375 static ssize_t ib_umad_read(struct file *filp, char __user *buf,
376 			    size_t count, loff_t *pos)
377 {
378 	struct ib_umad_file *file = filp->private_data;
379 	struct ib_umad_packet *packet;
380 	ssize_t ret;
381 
382 	if (count < hdr_size(file))
383 		return -EINVAL;
384 
385 	mutex_lock(&file->mutex);
386 
387 	if (file->agents_dead) {
388 		mutex_unlock(&file->mutex);
389 		return -EIO;
390 	}
391 
392 	while (list_empty(&file->recv_list)) {
393 		mutex_unlock(&file->mutex);
394 
395 		if (filp->f_flags & O_NONBLOCK)
396 			return -EAGAIN;
397 
398 		if (wait_event_interruptible(file->recv_wait,
399 					     !list_empty(&file->recv_list)))
400 			return -ERESTARTSYS;
401 
402 		mutex_lock(&file->mutex);
403 	}
404 
405 	if (file->agents_dead) {
406 		mutex_unlock(&file->mutex);
407 		return -EIO;
408 	}
409 
410 	packet = list_entry(file->recv_list.next, struct ib_umad_packet, list);
411 	list_del(&packet->list);
412 
413 	mutex_unlock(&file->mutex);
414 
415 	if (packet->recv_wc)
416 		ret = copy_recv_mad(file, buf, packet, count);
417 	else
418 		ret = copy_send_mad(file, buf, packet, count);
419 
420 	if (ret < 0) {
421 		/* Requeue packet */
422 		mutex_lock(&file->mutex);
423 		list_add(&packet->list, &file->recv_list);
424 		mutex_unlock(&file->mutex);
425 	} else {
426 		if (packet->recv_wc)
427 			ib_free_recv_mad(packet->recv_wc);
428 		kfree(packet);
429 	}
430 	return ret;
431 }
432 
433 static int copy_rmpp_mad(struct ib_mad_send_buf *msg, const char __user *buf)
434 {
435 	int left, seg;
436 
437 	/* Copy class specific header */
438 	if ((msg->hdr_len > IB_MGMT_RMPP_HDR) &&
439 	    copy_from_user(msg->mad + IB_MGMT_RMPP_HDR, buf + IB_MGMT_RMPP_HDR,
440 			   msg->hdr_len - IB_MGMT_RMPP_HDR))
441 		return -EFAULT;
442 
443 	/* All headers are in place.  Copy data segments. */
444 	for (seg = 1, left = msg->data_len, buf += msg->hdr_len; left > 0;
445 	     seg++, left -= msg->seg_size, buf += msg->seg_size) {
446 		if (copy_from_user(ib_get_rmpp_segment(msg, seg), buf,
447 				   min(left, msg->seg_size)))
448 			return -EFAULT;
449 	}
450 	return 0;
451 }
452 
453 static int same_destination(struct ib_user_mad_hdr *hdr1,
454 			    struct ib_user_mad_hdr *hdr2)
455 {
456 	if (!hdr1->grh_present && !hdr2->grh_present)
457 	   return (hdr1->lid == hdr2->lid);
458 
459 	if (hdr1->grh_present && hdr2->grh_present)
460 	   return !memcmp(hdr1->gid, hdr2->gid, 16);
461 
462 	return 0;
463 }
464 
465 static int is_duplicate(struct ib_umad_file *file,
466 			struct ib_umad_packet *packet)
467 {
468 	struct ib_umad_packet *sent_packet;
469 	struct ib_mad_hdr *sent_hdr, *hdr;
470 
471 	hdr = (struct ib_mad_hdr *) packet->mad.data;
472 	list_for_each_entry(sent_packet, &file->send_list, list) {
473 		sent_hdr = (struct ib_mad_hdr *) sent_packet->mad.data;
474 
475 		if ((hdr->tid != sent_hdr->tid) ||
476 		    (hdr->mgmt_class != sent_hdr->mgmt_class))
477 			continue;
478 
479 		/*
480 		 * No need to be overly clever here.  If two new operations have
481 		 * the same TID, reject the second as a duplicate.  This is more
482 		 * restrictive than required by the spec.
483 		 */
484 		if (!ib_response_mad(hdr)) {
485 			if (!ib_response_mad(sent_hdr))
486 				return 1;
487 			continue;
488 		} else if (!ib_response_mad(sent_hdr))
489 			continue;
490 
491 		if (same_destination(&packet->mad.hdr, &sent_packet->mad.hdr))
492 			return 1;
493 	}
494 
495 	return 0;
496 }
497 
498 static ssize_t ib_umad_write(struct file *filp, const char __user *buf,
499 			     size_t count, loff_t *pos)
500 {
501 	struct ib_umad_file *file = filp->private_data;
502 	struct ib_rmpp_mad_hdr *rmpp_mad_hdr;
503 	struct ib_umad_packet *packet;
504 	struct ib_mad_agent *agent;
505 	struct rdma_ah_attr ah_attr;
506 	struct ib_ah *ah;
507 	__be64 *tid;
508 	int ret, data_len, hdr_len, copy_offset, rmpp_active;
509 	u8 base_version;
510 
511 	if (count < hdr_size(file) + IB_MGMT_RMPP_HDR)
512 		return -EINVAL;
513 
514 	packet = kzalloc(sizeof(*packet) + IB_MGMT_RMPP_HDR, GFP_KERNEL);
515 	if (!packet)
516 		return -ENOMEM;
517 
518 	if (copy_from_user(&packet->mad, buf, hdr_size(file))) {
519 		ret = -EFAULT;
520 		goto err;
521 	}
522 
523 	if (packet->mad.hdr.id >= IB_UMAD_MAX_AGENTS) {
524 		ret = -EINVAL;
525 		goto err;
526 	}
527 
528 	buf += hdr_size(file);
529 
530 	if (copy_from_user(packet->mad.data, buf, IB_MGMT_RMPP_HDR)) {
531 		ret = -EFAULT;
532 		goto err;
533 	}
534 
535 	mutex_lock(&file->mutex);
536 
537 	trace_ib_umad_write(file, &packet->mad.hdr,
538 			    (struct ib_mad_hdr *)&packet->mad.data);
539 
540 	agent = __get_agent(file, packet->mad.hdr.id);
541 	if (!agent) {
542 		ret = -EIO;
543 		goto err_up;
544 	}
545 
546 	memset(&ah_attr, 0, sizeof ah_attr);
547 	ah_attr.type = rdma_ah_find_type(agent->device,
548 					 file->port->port_num);
549 	rdma_ah_set_dlid(&ah_attr, be16_to_cpu(packet->mad.hdr.lid));
550 	rdma_ah_set_sl(&ah_attr, packet->mad.hdr.sl);
551 	rdma_ah_set_path_bits(&ah_attr, packet->mad.hdr.path_bits);
552 	rdma_ah_set_port_num(&ah_attr, file->port->port_num);
553 	if (packet->mad.hdr.grh_present) {
554 		rdma_ah_set_grh(&ah_attr, NULL,
555 				be32_to_cpu(packet->mad.hdr.flow_label),
556 				packet->mad.hdr.gid_index,
557 				packet->mad.hdr.hop_limit,
558 				packet->mad.hdr.traffic_class);
559 		rdma_ah_set_dgid_raw(&ah_attr, packet->mad.hdr.gid);
560 	}
561 
562 	ah = rdma_create_user_ah(agent->qp->pd, &ah_attr, NULL);
563 	if (IS_ERR(ah)) {
564 		ret = PTR_ERR(ah);
565 		goto err_up;
566 	}
567 
568 	rmpp_mad_hdr = (struct ib_rmpp_mad_hdr *)packet->mad.data;
569 	hdr_len = ib_get_mad_data_offset(rmpp_mad_hdr->mad_hdr.mgmt_class);
570 
571 	if (ib_is_mad_class_rmpp(rmpp_mad_hdr->mad_hdr.mgmt_class)
572 	    && ib_mad_kernel_rmpp_agent(agent)) {
573 		copy_offset = IB_MGMT_RMPP_HDR;
574 		rmpp_active = ib_get_rmpp_flags(&rmpp_mad_hdr->rmpp_hdr) &
575 						IB_MGMT_RMPP_FLAG_ACTIVE;
576 	} else {
577 		copy_offset = IB_MGMT_MAD_HDR;
578 		rmpp_active = 0;
579 	}
580 
581 	base_version = ((struct ib_mad_hdr *)&packet->mad.data)->base_version;
582 	data_len = count - hdr_size(file) - hdr_len;
583 	packet->msg = ib_create_send_mad(agent,
584 					 be32_to_cpu(packet->mad.hdr.qpn),
585 					 packet->mad.hdr.pkey_index, rmpp_active,
586 					 hdr_len, data_len, GFP_KERNEL,
587 					 base_version);
588 	if (IS_ERR(packet->msg)) {
589 		ret = PTR_ERR(packet->msg);
590 		goto err_ah;
591 	}
592 
593 	packet->msg->ah		= ah;
594 	packet->msg->timeout_ms = packet->mad.hdr.timeout_ms;
595 	packet->msg->retries	= packet->mad.hdr.retries;
596 	packet->msg->context[0] = packet;
597 
598 	/* Copy MAD header.  Any RMPP header is already in place. */
599 	memcpy(packet->msg->mad, packet->mad.data, IB_MGMT_MAD_HDR);
600 
601 	if (!rmpp_active) {
602 		if (copy_from_user(packet->msg->mad + copy_offset,
603 				   buf + copy_offset,
604 				   hdr_len + data_len - copy_offset)) {
605 			ret = -EFAULT;
606 			goto err_msg;
607 		}
608 	} else {
609 		ret = copy_rmpp_mad(packet->msg, buf);
610 		if (ret)
611 			goto err_msg;
612 	}
613 
614 	/*
615 	 * Set the high-order part of the transaction ID to make MADs from
616 	 * different agents unique, and allow routing responses back to the
617 	 * original requestor.
618 	 */
619 	if (!ib_response_mad(packet->msg->mad)) {
620 		tid = &((struct ib_mad_hdr *) packet->msg->mad)->tid;
621 		*tid = cpu_to_be64(((u64) agent->hi_tid) << 32 |
622 				   (be64_to_cpup(tid) & 0xffffffff));
623 		rmpp_mad_hdr->mad_hdr.tid = *tid;
624 	}
625 
626 	if (!ib_mad_kernel_rmpp_agent(agent)
627 	    && ib_is_mad_class_rmpp(rmpp_mad_hdr->mad_hdr.mgmt_class)
628 	    && (ib_get_rmpp_flags(&rmpp_mad_hdr->rmpp_hdr) & IB_MGMT_RMPP_FLAG_ACTIVE)) {
629 		spin_lock_irq(&file->send_lock);
630 		list_add_tail(&packet->list, &file->send_list);
631 		spin_unlock_irq(&file->send_lock);
632 	} else {
633 		spin_lock_irq(&file->send_lock);
634 		ret = is_duplicate(file, packet);
635 		if (!ret)
636 			list_add_tail(&packet->list, &file->send_list);
637 		spin_unlock_irq(&file->send_lock);
638 		if (ret) {
639 			ret = -EINVAL;
640 			goto err_msg;
641 		}
642 	}
643 
644 	ret = ib_post_send_mad(packet->msg, NULL);
645 	if (ret)
646 		goto err_send;
647 
648 	mutex_unlock(&file->mutex);
649 	return count;
650 
651 err_send:
652 	dequeue_send(file, packet);
653 err_msg:
654 	ib_free_send_mad(packet->msg);
655 err_ah:
656 	rdma_destroy_ah(ah, RDMA_DESTROY_AH_SLEEPABLE);
657 err_up:
658 	mutex_unlock(&file->mutex);
659 err:
660 	kfree(packet);
661 	return ret;
662 }
663 
664 static __poll_t ib_umad_poll(struct file *filp, struct poll_table_struct *wait)
665 {
666 	struct ib_umad_file *file = filp->private_data;
667 
668 	/* we will always be able to post a MAD send */
669 	__poll_t mask = EPOLLOUT | EPOLLWRNORM;
670 
671 	mutex_lock(&file->mutex);
672 	poll_wait(filp, &file->recv_wait, wait);
673 
674 	if (!list_empty(&file->recv_list))
675 		mask |= EPOLLIN | EPOLLRDNORM;
676 	if (file->agents_dead)
677 		mask = EPOLLERR;
678 	mutex_unlock(&file->mutex);
679 
680 	return mask;
681 }
682 
683 static int ib_umad_reg_agent(struct ib_umad_file *file, void __user *arg,
684 			     int compat_method_mask)
685 {
686 	struct ib_user_mad_reg_req ureq;
687 	struct ib_mad_reg_req req;
688 	struct ib_mad_agent *agent = NULL;
689 	int agent_id;
690 	int ret;
691 
692 	mutex_lock(&file->port->file_mutex);
693 	mutex_lock(&file->mutex);
694 
695 	if (!file->port->ib_dev) {
696 		dev_notice(&file->port->dev, "%s: invalid device\n", __func__);
697 		ret = -EPIPE;
698 		goto out;
699 	}
700 
701 	if (copy_from_user(&ureq, arg, sizeof ureq)) {
702 		ret = -EFAULT;
703 		goto out;
704 	}
705 
706 	if (ureq.qpn != 0 && ureq.qpn != 1) {
707 		dev_notice(&file->port->dev,
708 			   "%s: invalid QPN %u specified\n", __func__,
709 			   ureq.qpn);
710 		ret = -EINVAL;
711 		goto out;
712 	}
713 
714 	for (agent_id = 0; agent_id < IB_UMAD_MAX_AGENTS; ++agent_id)
715 		if (!__get_agent(file, agent_id))
716 			goto found;
717 
718 	dev_notice(&file->port->dev, "%s: Max Agents (%u) reached\n", __func__,
719 		   IB_UMAD_MAX_AGENTS);
720 
721 	ret = -ENOMEM;
722 	goto out;
723 
724 found:
725 	if (ureq.mgmt_class) {
726 		memset(&req, 0, sizeof(req));
727 		req.mgmt_class         = ureq.mgmt_class;
728 		req.mgmt_class_version = ureq.mgmt_class_version;
729 		memcpy(req.oui, ureq.oui, sizeof req.oui);
730 
731 		if (compat_method_mask) {
732 			u32 *umm = (u32 *) ureq.method_mask;
733 			int i;
734 
735 			for (i = 0; i < BITS_TO_LONGS(IB_MGMT_MAX_METHODS); ++i)
736 				req.method_mask[i] =
737 					umm[i * 2] | ((u64) umm[i * 2 + 1] << 32);
738 		} else
739 			memcpy(req.method_mask, ureq.method_mask,
740 			       sizeof req.method_mask);
741 	}
742 
743 	agent = ib_register_mad_agent(file->port->ib_dev, file->port->port_num,
744 				      ureq.qpn ? IB_QPT_GSI : IB_QPT_SMI,
745 				      ureq.mgmt_class ? &req : NULL,
746 				      ureq.rmpp_version,
747 				      send_handler, recv_handler, file, 0);
748 	if (IS_ERR(agent)) {
749 		ret = PTR_ERR(agent);
750 		agent = NULL;
751 		goto out;
752 	}
753 
754 	if (put_user(agent_id,
755 		     (u32 __user *) (arg + offsetof(struct ib_user_mad_reg_req, id)))) {
756 		ret = -EFAULT;
757 		goto out;
758 	}
759 
760 	if (!file->already_used) {
761 		file->already_used = 1;
762 		if (!file->use_pkey_index) {
763 			dev_warn(&file->port->dev,
764 				"process %s did not enable P_Key index support.\n",
765 				current->comm);
766 			dev_warn(&file->port->dev,
767 				"   Documentation/infiniband/user_mad.rst has info on the new ABI.\n");
768 		}
769 	}
770 
771 	file->agent[agent_id] = agent;
772 	ret = 0;
773 
774 out:
775 	mutex_unlock(&file->mutex);
776 
777 	if (ret && agent)
778 		ib_unregister_mad_agent(agent);
779 
780 	mutex_unlock(&file->port->file_mutex);
781 
782 	return ret;
783 }
784 
785 static int ib_umad_reg_agent2(struct ib_umad_file *file, void __user *arg)
786 {
787 	struct ib_user_mad_reg_req2 ureq;
788 	struct ib_mad_reg_req req;
789 	struct ib_mad_agent *agent = NULL;
790 	int agent_id;
791 	int ret;
792 
793 	mutex_lock(&file->port->file_mutex);
794 	mutex_lock(&file->mutex);
795 
796 	if (!file->port->ib_dev) {
797 		dev_notice(&file->port->dev, "%s: invalid device\n", __func__);
798 		ret = -EPIPE;
799 		goto out;
800 	}
801 
802 	if (copy_from_user(&ureq, arg, sizeof(ureq))) {
803 		ret = -EFAULT;
804 		goto out;
805 	}
806 
807 	if (ureq.qpn != 0 && ureq.qpn != 1) {
808 		dev_notice(&file->port->dev, "%s: invalid QPN %u specified\n",
809 			   __func__, ureq.qpn);
810 		ret = -EINVAL;
811 		goto out;
812 	}
813 
814 	if (ureq.flags & ~IB_USER_MAD_REG_FLAGS_CAP) {
815 		dev_notice(&file->port->dev,
816 			   "%s failed: invalid registration flags specified 0x%x; supported 0x%x\n",
817 			   __func__, ureq.flags, IB_USER_MAD_REG_FLAGS_CAP);
818 		ret = -EINVAL;
819 
820 		if (put_user((u32)IB_USER_MAD_REG_FLAGS_CAP,
821 				(u32 __user *) (arg + offsetof(struct
822 				ib_user_mad_reg_req2, flags))))
823 			ret = -EFAULT;
824 
825 		goto out;
826 	}
827 
828 	for (agent_id = 0; agent_id < IB_UMAD_MAX_AGENTS; ++agent_id)
829 		if (!__get_agent(file, agent_id))
830 			goto found;
831 
832 	dev_notice(&file->port->dev, "%s: Max Agents (%u) reached\n", __func__,
833 		   IB_UMAD_MAX_AGENTS);
834 	ret = -ENOMEM;
835 	goto out;
836 
837 found:
838 	if (ureq.mgmt_class) {
839 		memset(&req, 0, sizeof(req));
840 		req.mgmt_class         = ureq.mgmt_class;
841 		req.mgmt_class_version = ureq.mgmt_class_version;
842 		if (ureq.oui & 0xff000000) {
843 			dev_notice(&file->port->dev,
844 				   "%s failed: oui invalid 0x%08x\n", __func__,
845 				   ureq.oui);
846 			ret = -EINVAL;
847 			goto out;
848 		}
849 		req.oui[2] =  ureq.oui & 0x0000ff;
850 		req.oui[1] = (ureq.oui & 0x00ff00) >> 8;
851 		req.oui[0] = (ureq.oui & 0xff0000) >> 16;
852 		memcpy(req.method_mask, ureq.method_mask,
853 			sizeof(req.method_mask));
854 	}
855 
856 	agent = ib_register_mad_agent(file->port->ib_dev, file->port->port_num,
857 				      ureq.qpn ? IB_QPT_GSI : IB_QPT_SMI,
858 				      ureq.mgmt_class ? &req : NULL,
859 				      ureq.rmpp_version,
860 				      send_handler, recv_handler, file,
861 				      ureq.flags);
862 	if (IS_ERR(agent)) {
863 		ret = PTR_ERR(agent);
864 		agent = NULL;
865 		goto out;
866 	}
867 
868 	if (put_user(agent_id,
869 		     (u32 __user *)(arg +
870 				offsetof(struct ib_user_mad_reg_req2, id)))) {
871 		ret = -EFAULT;
872 		goto out;
873 	}
874 
875 	if (!file->already_used) {
876 		file->already_used = 1;
877 		file->use_pkey_index = 1;
878 	}
879 
880 	file->agent[agent_id] = agent;
881 	ret = 0;
882 
883 out:
884 	mutex_unlock(&file->mutex);
885 
886 	if (ret && agent)
887 		ib_unregister_mad_agent(agent);
888 
889 	mutex_unlock(&file->port->file_mutex);
890 
891 	return ret;
892 }
893 
894 
895 static int ib_umad_unreg_agent(struct ib_umad_file *file, u32 __user *arg)
896 {
897 	struct ib_mad_agent *agent = NULL;
898 	u32 id;
899 	int ret = 0;
900 
901 	if (get_user(id, arg))
902 		return -EFAULT;
903 	if (id >= IB_UMAD_MAX_AGENTS)
904 		return -EINVAL;
905 
906 	mutex_lock(&file->port->file_mutex);
907 	mutex_lock(&file->mutex);
908 
909 	id = array_index_nospec(id, IB_UMAD_MAX_AGENTS);
910 	if (!__get_agent(file, id)) {
911 		ret = -EINVAL;
912 		goto out;
913 	}
914 
915 	agent = file->agent[id];
916 	file->agent[id] = NULL;
917 
918 out:
919 	mutex_unlock(&file->mutex);
920 
921 	if (agent)
922 		ib_unregister_mad_agent(agent);
923 
924 	mutex_unlock(&file->port->file_mutex);
925 
926 	return ret;
927 }
928 
929 static long ib_umad_enable_pkey(struct ib_umad_file *file)
930 {
931 	int ret = 0;
932 
933 	mutex_lock(&file->mutex);
934 	if (file->already_used)
935 		ret = -EINVAL;
936 	else
937 		file->use_pkey_index = 1;
938 	mutex_unlock(&file->mutex);
939 
940 	return ret;
941 }
942 
943 static long ib_umad_ioctl(struct file *filp, unsigned int cmd,
944 			  unsigned long arg)
945 {
946 	switch (cmd) {
947 	case IB_USER_MAD_REGISTER_AGENT:
948 		return ib_umad_reg_agent(filp->private_data, (void __user *) arg, 0);
949 	case IB_USER_MAD_UNREGISTER_AGENT:
950 		return ib_umad_unreg_agent(filp->private_data, (__u32 __user *) arg);
951 	case IB_USER_MAD_ENABLE_PKEY:
952 		return ib_umad_enable_pkey(filp->private_data);
953 	case IB_USER_MAD_REGISTER_AGENT2:
954 		return ib_umad_reg_agent2(filp->private_data, (void __user *) arg);
955 	default:
956 		return -ENOIOCTLCMD;
957 	}
958 }
959 
960 #ifdef CONFIG_COMPAT
961 static long ib_umad_compat_ioctl(struct file *filp, unsigned int cmd,
962 				 unsigned long arg)
963 {
964 	switch (cmd) {
965 	case IB_USER_MAD_REGISTER_AGENT:
966 		return ib_umad_reg_agent(filp->private_data, compat_ptr(arg), 1);
967 	case IB_USER_MAD_UNREGISTER_AGENT:
968 		return ib_umad_unreg_agent(filp->private_data, compat_ptr(arg));
969 	case IB_USER_MAD_ENABLE_PKEY:
970 		return ib_umad_enable_pkey(filp->private_data);
971 	case IB_USER_MAD_REGISTER_AGENT2:
972 		return ib_umad_reg_agent2(filp->private_data, compat_ptr(arg));
973 	default:
974 		return -ENOIOCTLCMD;
975 	}
976 }
977 #endif
978 
979 /*
980  * ib_umad_open() does not need the BKL:
981  *
982  *  - the ib_umad_port structures are properly reference counted, and
983  *    everything else is purely local to the file being created, so
984  *    races against other open calls are not a problem;
985  *  - the ioctl method does not affect any global state outside of the
986  *    file structure being operated on;
987  */
988 static int ib_umad_open(struct inode *inode, struct file *filp)
989 {
990 	struct ib_umad_port *port;
991 	struct ib_umad_file *file;
992 	int ret = 0;
993 
994 	port = container_of(inode->i_cdev, struct ib_umad_port, cdev);
995 
996 	mutex_lock(&port->file_mutex);
997 
998 	if (!port->ib_dev) {
999 		ret = -ENXIO;
1000 		goto out;
1001 	}
1002 
1003 	if (!rdma_dev_access_netns(port->ib_dev, current->nsproxy->net_ns)) {
1004 		ret = -EPERM;
1005 		goto out;
1006 	}
1007 
1008 	file = kzalloc(sizeof(*file), GFP_KERNEL);
1009 	if (!file) {
1010 		ret = -ENOMEM;
1011 		goto out;
1012 	}
1013 
1014 	mutex_init(&file->mutex);
1015 	spin_lock_init(&file->send_lock);
1016 	INIT_LIST_HEAD(&file->recv_list);
1017 	INIT_LIST_HEAD(&file->send_list);
1018 	init_waitqueue_head(&file->recv_wait);
1019 
1020 	file->port = port;
1021 	filp->private_data = file;
1022 
1023 	list_add_tail(&file->port_list, &port->file_list);
1024 
1025 	stream_open(inode, filp);
1026 out:
1027 	mutex_unlock(&port->file_mutex);
1028 	return ret;
1029 }
1030 
1031 static int ib_umad_close(struct inode *inode, struct file *filp)
1032 {
1033 	struct ib_umad_file *file = filp->private_data;
1034 	struct ib_umad_packet *packet, *tmp;
1035 	int already_dead;
1036 	int i;
1037 
1038 	mutex_lock(&file->port->file_mutex);
1039 	mutex_lock(&file->mutex);
1040 
1041 	already_dead = file->agents_dead;
1042 	file->agents_dead = 1;
1043 
1044 	list_for_each_entry_safe(packet, tmp, &file->recv_list, list) {
1045 		if (packet->recv_wc)
1046 			ib_free_recv_mad(packet->recv_wc);
1047 		kfree(packet);
1048 	}
1049 
1050 	list_del(&file->port_list);
1051 
1052 	mutex_unlock(&file->mutex);
1053 
1054 	if (!already_dead)
1055 		for (i = 0; i < IB_UMAD_MAX_AGENTS; ++i)
1056 			if (file->agent[i])
1057 				ib_unregister_mad_agent(file->agent[i]);
1058 
1059 	mutex_unlock(&file->port->file_mutex);
1060 	mutex_destroy(&file->mutex);
1061 	kfree(file);
1062 	return 0;
1063 }
1064 
1065 static const struct file_operations umad_fops = {
1066 	.owner		= THIS_MODULE,
1067 	.read		= ib_umad_read,
1068 	.write		= ib_umad_write,
1069 	.poll		= ib_umad_poll,
1070 	.unlocked_ioctl = ib_umad_ioctl,
1071 #ifdef CONFIG_COMPAT
1072 	.compat_ioctl	= ib_umad_compat_ioctl,
1073 #endif
1074 	.open		= ib_umad_open,
1075 	.release	= ib_umad_close,
1076 	.llseek		= no_llseek,
1077 };
1078 
1079 static int ib_umad_sm_open(struct inode *inode, struct file *filp)
1080 {
1081 	struct ib_umad_port *port;
1082 	struct ib_port_modify props = {
1083 		.set_port_cap_mask = IB_PORT_SM
1084 	};
1085 	int ret;
1086 
1087 	port = container_of(inode->i_cdev, struct ib_umad_port, sm_cdev);
1088 
1089 	if (filp->f_flags & O_NONBLOCK) {
1090 		if (down_trylock(&port->sm_sem)) {
1091 			ret = -EAGAIN;
1092 			goto fail;
1093 		}
1094 	} else {
1095 		if (down_interruptible(&port->sm_sem)) {
1096 			ret = -ERESTARTSYS;
1097 			goto fail;
1098 		}
1099 	}
1100 
1101 	if (!rdma_dev_access_netns(port->ib_dev, current->nsproxy->net_ns)) {
1102 		ret = -EPERM;
1103 		goto err_up_sem;
1104 	}
1105 
1106 	ret = ib_modify_port(port->ib_dev, port->port_num, 0, &props);
1107 	if (ret)
1108 		goto err_up_sem;
1109 
1110 	filp->private_data = port;
1111 
1112 	nonseekable_open(inode, filp);
1113 	return 0;
1114 
1115 err_up_sem:
1116 	up(&port->sm_sem);
1117 
1118 fail:
1119 	return ret;
1120 }
1121 
1122 static int ib_umad_sm_close(struct inode *inode, struct file *filp)
1123 {
1124 	struct ib_umad_port *port = filp->private_data;
1125 	struct ib_port_modify props = {
1126 		.clr_port_cap_mask = IB_PORT_SM
1127 	};
1128 	int ret = 0;
1129 
1130 	mutex_lock(&port->file_mutex);
1131 	if (port->ib_dev)
1132 		ret = ib_modify_port(port->ib_dev, port->port_num, 0, &props);
1133 	mutex_unlock(&port->file_mutex);
1134 
1135 	up(&port->sm_sem);
1136 
1137 	return ret;
1138 }
1139 
1140 static const struct file_operations umad_sm_fops = {
1141 	.owner	 = THIS_MODULE,
1142 	.open	 = ib_umad_sm_open,
1143 	.release = ib_umad_sm_close,
1144 	.llseek	 = no_llseek,
1145 };
1146 
1147 static struct ib_umad_port *get_port(struct ib_device *ibdev,
1148 				     struct ib_umad_device *umad_dev,
1149 				     u32 port)
1150 {
1151 	if (!umad_dev)
1152 		return ERR_PTR(-EOPNOTSUPP);
1153 	if (!rdma_is_port_valid(ibdev, port))
1154 		return ERR_PTR(-EINVAL);
1155 	if (!rdma_cap_ib_mad(ibdev, port))
1156 		return ERR_PTR(-EOPNOTSUPP);
1157 
1158 	return &umad_dev->ports[port - rdma_start_port(ibdev)];
1159 }
1160 
1161 static int ib_umad_get_nl_info(struct ib_device *ibdev, void *client_data,
1162 			       struct ib_client_nl_info *res)
1163 {
1164 	struct ib_umad_port *port = get_port(ibdev, client_data, res->port);
1165 
1166 	if (IS_ERR(port))
1167 		return PTR_ERR(port);
1168 
1169 	res->abi = IB_USER_MAD_ABI_VERSION;
1170 	res->cdev = &port->dev;
1171 	return 0;
1172 }
1173 
1174 static struct ib_client umad_client = {
1175 	.name   = "umad",
1176 	.add    = ib_umad_add_one,
1177 	.remove = ib_umad_remove_one,
1178 	.get_nl_info = ib_umad_get_nl_info,
1179 };
1180 MODULE_ALIAS_RDMA_CLIENT("umad");
1181 
1182 static int ib_issm_get_nl_info(struct ib_device *ibdev, void *client_data,
1183 			       struct ib_client_nl_info *res)
1184 {
1185 	struct ib_umad_port *port = get_port(ibdev, client_data, res->port);
1186 
1187 	if (IS_ERR(port))
1188 		return PTR_ERR(port);
1189 
1190 	res->abi = IB_USER_MAD_ABI_VERSION;
1191 	res->cdev = &port->sm_dev;
1192 	return 0;
1193 }
1194 
1195 static struct ib_client issm_client = {
1196 	.name = "issm",
1197 	.get_nl_info = ib_issm_get_nl_info,
1198 };
1199 MODULE_ALIAS_RDMA_CLIENT("issm");
1200 
1201 static ssize_t ibdev_show(struct device *dev, struct device_attribute *attr,
1202 			  char *buf)
1203 {
1204 	struct ib_umad_port *port = dev_get_drvdata(dev);
1205 
1206 	if (!port)
1207 		return -ENODEV;
1208 
1209 	return sysfs_emit(buf, "%s\n", dev_name(&port->ib_dev->dev));
1210 }
1211 static DEVICE_ATTR_RO(ibdev);
1212 
1213 static ssize_t port_show(struct device *dev, struct device_attribute *attr,
1214 			 char *buf)
1215 {
1216 	struct ib_umad_port *port = dev_get_drvdata(dev);
1217 
1218 	if (!port)
1219 		return -ENODEV;
1220 
1221 	return sysfs_emit(buf, "%d\n", port->port_num);
1222 }
1223 static DEVICE_ATTR_RO(port);
1224 
1225 static struct attribute *umad_class_dev_attrs[] = {
1226 	&dev_attr_ibdev.attr,
1227 	&dev_attr_port.attr,
1228 	NULL,
1229 };
1230 ATTRIBUTE_GROUPS(umad_class_dev);
1231 
1232 static char *umad_devnode(const struct device *dev, umode_t *mode)
1233 {
1234 	return kasprintf(GFP_KERNEL, "infiniband/%s", dev_name(dev));
1235 }
1236 
1237 static ssize_t abi_version_show(const struct class *class,
1238 				const struct class_attribute *attr, char *buf)
1239 {
1240 	return sysfs_emit(buf, "%d\n", IB_USER_MAD_ABI_VERSION);
1241 }
1242 static CLASS_ATTR_RO(abi_version);
1243 
1244 static struct attribute *umad_class_attrs[] = {
1245 	&class_attr_abi_version.attr,
1246 	NULL,
1247 };
1248 ATTRIBUTE_GROUPS(umad_class);
1249 
1250 static struct class umad_class = {
1251 	.name		= "infiniband_mad",
1252 	.devnode	= umad_devnode,
1253 	.class_groups	= umad_class_groups,
1254 	.dev_groups	= umad_class_dev_groups,
1255 };
1256 
1257 static void ib_umad_release_port(struct device *device)
1258 {
1259 	struct ib_umad_port *port = dev_get_drvdata(device);
1260 	struct ib_umad_device *umad_dev = port->umad_dev;
1261 
1262 	ib_umad_dev_put(umad_dev);
1263 }
1264 
1265 static void ib_umad_init_port_dev(struct device *dev,
1266 				  struct ib_umad_port *port,
1267 				  const struct ib_device *device)
1268 {
1269 	device_initialize(dev);
1270 	ib_umad_dev_get(port->umad_dev);
1271 	dev->class = &umad_class;
1272 	dev->parent = device->dev.parent;
1273 	dev_set_drvdata(dev, port);
1274 	dev->release = ib_umad_release_port;
1275 }
1276 
1277 static int ib_umad_init_port(struct ib_device *device, int port_num,
1278 			     struct ib_umad_device *umad_dev,
1279 			     struct ib_umad_port *port)
1280 {
1281 	int devnum;
1282 	dev_t base_umad;
1283 	dev_t base_issm;
1284 	int ret;
1285 
1286 	devnum = ida_alloc_max(&umad_ida, IB_UMAD_MAX_PORTS - 1, GFP_KERNEL);
1287 	if (devnum < 0)
1288 		return -1;
1289 	port->dev_num = devnum;
1290 	if (devnum >= IB_UMAD_NUM_FIXED_MINOR) {
1291 		base_umad = dynamic_umad_dev + devnum - IB_UMAD_NUM_FIXED_MINOR;
1292 		base_issm = dynamic_issm_dev + devnum - IB_UMAD_NUM_FIXED_MINOR;
1293 	} else {
1294 		base_umad = devnum + base_umad_dev;
1295 		base_issm = devnum + base_issm_dev;
1296 	}
1297 
1298 	port->ib_dev   = device;
1299 	port->umad_dev = umad_dev;
1300 	port->port_num = port_num;
1301 	sema_init(&port->sm_sem, 1);
1302 	mutex_init(&port->file_mutex);
1303 	INIT_LIST_HEAD(&port->file_list);
1304 
1305 	ib_umad_init_port_dev(&port->dev, port, device);
1306 	port->dev.devt = base_umad;
1307 	dev_set_name(&port->dev, "umad%d", port->dev_num);
1308 	cdev_init(&port->cdev, &umad_fops);
1309 	port->cdev.owner = THIS_MODULE;
1310 
1311 	ret = cdev_device_add(&port->cdev, &port->dev);
1312 	if (ret)
1313 		goto err_cdev;
1314 
1315 	ib_umad_init_port_dev(&port->sm_dev, port, device);
1316 	port->sm_dev.devt = base_issm;
1317 	dev_set_name(&port->sm_dev, "issm%d", port->dev_num);
1318 	cdev_init(&port->sm_cdev, &umad_sm_fops);
1319 	port->sm_cdev.owner = THIS_MODULE;
1320 
1321 	ret = cdev_device_add(&port->sm_cdev, &port->sm_dev);
1322 	if (ret)
1323 		goto err_dev;
1324 
1325 	return 0;
1326 
1327 err_dev:
1328 	put_device(&port->sm_dev);
1329 	cdev_device_del(&port->cdev, &port->dev);
1330 err_cdev:
1331 	put_device(&port->dev);
1332 	ida_free(&umad_ida, devnum);
1333 	return ret;
1334 }
1335 
1336 static void ib_umad_kill_port(struct ib_umad_port *port)
1337 {
1338 	struct ib_umad_file *file;
1339 	int id;
1340 
1341 	cdev_device_del(&port->sm_cdev, &port->sm_dev);
1342 	cdev_device_del(&port->cdev, &port->dev);
1343 
1344 	mutex_lock(&port->file_mutex);
1345 
1346 	/* Mark ib_dev NULL and block ioctl or other file ops to progress
1347 	 * further.
1348 	 */
1349 	port->ib_dev = NULL;
1350 
1351 	list_for_each_entry(file, &port->file_list, port_list) {
1352 		mutex_lock(&file->mutex);
1353 		file->agents_dead = 1;
1354 		wake_up_interruptible(&file->recv_wait);
1355 		mutex_unlock(&file->mutex);
1356 
1357 		for (id = 0; id < IB_UMAD_MAX_AGENTS; ++id)
1358 			if (file->agent[id])
1359 				ib_unregister_mad_agent(file->agent[id]);
1360 	}
1361 
1362 	mutex_unlock(&port->file_mutex);
1363 
1364 	ida_free(&umad_ida, port->dev_num);
1365 
1366 	/* balances device_initialize() */
1367 	put_device(&port->sm_dev);
1368 	put_device(&port->dev);
1369 }
1370 
1371 static int ib_umad_add_one(struct ib_device *device)
1372 {
1373 	struct ib_umad_device *umad_dev;
1374 	int s, e, i;
1375 	int count = 0;
1376 	int ret;
1377 
1378 	s = rdma_start_port(device);
1379 	e = rdma_end_port(device);
1380 
1381 	umad_dev = kzalloc(struct_size(umad_dev, ports,
1382 				       size_add(size_sub(e, s), 1)),
1383 			   GFP_KERNEL);
1384 	if (!umad_dev)
1385 		return -ENOMEM;
1386 
1387 	kref_init(&umad_dev->kref);
1388 	for (i = s; i <= e; ++i) {
1389 		if (!rdma_cap_ib_mad(device, i))
1390 			continue;
1391 
1392 		ret = ib_umad_init_port(device, i, umad_dev,
1393 					&umad_dev->ports[i - s]);
1394 		if (ret)
1395 			goto err;
1396 
1397 		count++;
1398 	}
1399 
1400 	if (!count) {
1401 		ret = -EOPNOTSUPP;
1402 		goto free;
1403 	}
1404 
1405 	ib_set_client_data(device, &umad_client, umad_dev);
1406 
1407 	return 0;
1408 
1409 err:
1410 	while (--i >= s) {
1411 		if (!rdma_cap_ib_mad(device, i))
1412 			continue;
1413 
1414 		ib_umad_kill_port(&umad_dev->ports[i - s]);
1415 	}
1416 free:
1417 	/* balances kref_init */
1418 	ib_umad_dev_put(umad_dev);
1419 	return ret;
1420 }
1421 
1422 static void ib_umad_remove_one(struct ib_device *device, void *client_data)
1423 {
1424 	struct ib_umad_device *umad_dev = client_data;
1425 	unsigned int i;
1426 
1427 	rdma_for_each_port (device, i) {
1428 		if (rdma_cap_ib_mad(device, i))
1429 			ib_umad_kill_port(
1430 				&umad_dev->ports[i - rdma_start_port(device)]);
1431 	}
1432 	/* balances kref_init() */
1433 	ib_umad_dev_put(umad_dev);
1434 }
1435 
1436 static int __init ib_umad_init(void)
1437 {
1438 	int ret;
1439 
1440 	ret = register_chrdev_region(base_umad_dev,
1441 				     IB_UMAD_NUM_FIXED_MINOR * 2,
1442 				     umad_class.name);
1443 	if (ret) {
1444 		pr_err("couldn't register device number\n");
1445 		goto out;
1446 	}
1447 
1448 	ret = alloc_chrdev_region(&dynamic_umad_dev, 0,
1449 				  IB_UMAD_NUM_DYNAMIC_MINOR * 2,
1450 				  umad_class.name);
1451 	if (ret) {
1452 		pr_err("couldn't register dynamic device number\n");
1453 		goto out_alloc;
1454 	}
1455 	dynamic_issm_dev = dynamic_umad_dev + IB_UMAD_NUM_DYNAMIC_MINOR;
1456 
1457 	ret = class_register(&umad_class);
1458 	if (ret) {
1459 		pr_err("couldn't create class infiniband_mad\n");
1460 		goto out_chrdev;
1461 	}
1462 
1463 	ret = ib_register_client(&umad_client);
1464 	if (ret)
1465 		goto out_class;
1466 
1467 	ret = ib_register_client(&issm_client);
1468 	if (ret)
1469 		goto out_client;
1470 
1471 	return 0;
1472 
1473 out_client:
1474 	ib_unregister_client(&umad_client);
1475 out_class:
1476 	class_unregister(&umad_class);
1477 
1478 out_chrdev:
1479 	unregister_chrdev_region(dynamic_umad_dev,
1480 				 IB_UMAD_NUM_DYNAMIC_MINOR * 2);
1481 
1482 out_alloc:
1483 	unregister_chrdev_region(base_umad_dev,
1484 				 IB_UMAD_NUM_FIXED_MINOR * 2);
1485 
1486 out:
1487 	return ret;
1488 }
1489 
1490 static void __exit ib_umad_cleanup(void)
1491 {
1492 	ib_unregister_client(&issm_client);
1493 	ib_unregister_client(&umad_client);
1494 	class_unregister(&umad_class);
1495 	unregister_chrdev_region(base_umad_dev,
1496 				 IB_UMAD_NUM_FIXED_MINOR * 2);
1497 	unregister_chrdev_region(dynamic_umad_dev,
1498 				 IB_UMAD_NUM_DYNAMIC_MINOR * 2);
1499 }
1500 
1501 module_init(ib_umad_init);
1502 module_exit(ib_umad_cleanup);
1503