user_mad.c revision bc1db9af731a74c7eca04df5936214c800774113
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#include <linux/module.h>
37#include <linux/init.h>
38#include <linux/device.h>
39#include <linux/err.h>
40#include <linux/fs.h>
41#include <linux/cdev.h>
42#include <linux/dma-mapping.h>
43#include <linux/poll.h>
44#include <linux/mutex.h>
45#include <linux/kref.h>
46#include <linux/compat.h>
47#include <linux/sched.h>
48#include <linux/semaphore.h>
49#include <linux/slab.h>
50
51#include <asm/uaccess.h>
52
53#include <rdma/ib_mad.h>
54#include <rdma/ib_user_mad.h>
55
56MODULE_AUTHOR("Roland Dreier");
57MODULE_DESCRIPTION("InfiniBand userspace MAD packet access");
58MODULE_LICENSE("Dual BSD/GPL");
59
60enum {
61	IB_UMAD_MAX_PORTS  = 64,
62	IB_UMAD_MAX_AGENTS = 32,
63
64	IB_UMAD_MAJOR      = 231,
65	IB_UMAD_MINOR_BASE = 0
66};
67
68/*
69 * Our lifetime rules for these structs are the following:
70 * device special file is opened, we take a reference on the
71 * ib_umad_port's struct ib_umad_device. We drop these
72 * references in the corresponding close().
73 *
74 * In addition to references coming from open character devices, there
75 * is one more reference to each ib_umad_device representing the
76 * module's reference taken when allocating the ib_umad_device in
77 * ib_umad_add_one().
78 *
79 * When destroying an ib_umad_device, we drop the module's reference.
80 */
81
82struct ib_umad_port {
83	struct cdev           cdev;
84	struct device	      *dev;
85
86	struct cdev           sm_cdev;
87	struct device	      *sm_dev;
88	struct semaphore       sm_sem;
89
90	struct mutex	       file_mutex;
91	struct list_head       file_list;
92
93	struct ib_device      *ib_dev;
94	struct ib_umad_device *umad_dev;
95	int                    dev_num;
96	u8                     port_num;
97};
98
99struct ib_umad_device {
100	int                  start_port, end_port;
101	struct kref          ref;
102	struct ib_umad_port  port[0];
103};
104
105struct ib_umad_file {
106	struct mutex		mutex;
107	struct ib_umad_port    *port;
108	struct list_head	recv_list;
109	struct list_head	send_list;
110	struct list_head	port_list;
111	spinlock_t		send_lock;
112	wait_queue_head_t	recv_wait;
113	struct ib_mad_agent    *agent[IB_UMAD_MAX_AGENTS];
114	int			agents_dead;
115	u8			use_pkey_index;
116	u8			already_used;
117};
118
119struct ib_umad_packet {
120	struct ib_mad_send_buf *msg;
121	struct ib_mad_recv_wc  *recv_wc;
122	struct list_head   list;
123	int		   length;
124	struct ib_user_mad mad;
125};
126
127static struct class *umad_class;
128
129static const dev_t base_dev = MKDEV(IB_UMAD_MAJOR, IB_UMAD_MINOR_BASE);
130
131static DEFINE_SPINLOCK(port_lock);
132static DECLARE_BITMAP(dev_map, IB_UMAD_MAX_PORTS);
133
134static void ib_umad_add_one(struct ib_device *device);
135static void ib_umad_remove_one(struct ib_device *device);
136
137static void ib_umad_release_dev(struct kref *ref)
138{
139	struct ib_umad_device *dev =
140		container_of(ref, struct ib_umad_device, ref);
141
142	kfree(dev);
143}
144
145static int hdr_size(struct ib_umad_file *file)
146{
147	return file->use_pkey_index ? sizeof (struct ib_user_mad_hdr) :
148		sizeof (struct ib_user_mad_hdr_old);
149}
150
151/* caller must hold file->mutex */
152static struct ib_mad_agent *__get_agent(struct ib_umad_file *file, int id)
153{
154	return file->agents_dead ? NULL : file->agent[id];
155}
156
157static int queue_packet(struct ib_umad_file *file,
158			struct ib_mad_agent *agent,
159			struct ib_umad_packet *packet)
160{
161	int ret = 1;
162
163	mutex_lock(&file->mutex);
164
165	for (packet->mad.hdr.id = 0;
166	     packet->mad.hdr.id < IB_UMAD_MAX_AGENTS;
167	     packet->mad.hdr.id++)
168		if (agent == __get_agent(file, packet->mad.hdr.id)) {
169			list_add_tail(&packet->list, &file->recv_list);
170			wake_up_interruptible(&file->recv_wait);
171			ret = 0;
172			break;
173		}
174
175	mutex_unlock(&file->mutex);
176
177	return ret;
178}
179
180static void dequeue_send(struct ib_umad_file *file,
181			 struct ib_umad_packet *packet)
182{
183	spin_lock_irq(&file->send_lock);
184	list_del(&packet->list);
185	spin_unlock_irq(&file->send_lock);
186}
187
188static void send_handler(struct ib_mad_agent *agent,
189			 struct ib_mad_send_wc *send_wc)
190{
191	struct ib_umad_file *file = agent->context;
192	struct ib_umad_packet *packet = send_wc->send_buf->context[0];
193
194	dequeue_send(file, packet);
195	ib_destroy_ah(packet->msg->ah);
196	ib_free_send_mad(packet->msg);
197
198	if (send_wc->status == IB_WC_RESP_TIMEOUT_ERR) {
199		packet->length = IB_MGMT_MAD_HDR;
200		packet->mad.hdr.status = ETIMEDOUT;
201		if (!queue_packet(file, agent, packet))
202			return;
203	}
204	kfree(packet);
205}
206
207static void recv_handler(struct ib_mad_agent *agent,
208			 struct ib_mad_recv_wc *mad_recv_wc)
209{
210	struct ib_umad_file *file = agent->context;
211	struct ib_umad_packet *packet;
212
213	if (mad_recv_wc->wc->status != IB_WC_SUCCESS)
214		goto err1;
215
216	packet = kzalloc(sizeof *packet, GFP_KERNEL);
217	if (!packet)
218		goto err1;
219
220	packet->length = mad_recv_wc->mad_len;
221	packet->recv_wc = mad_recv_wc;
222
223	packet->mad.hdr.status	   = 0;
224	packet->mad.hdr.length	   = hdr_size(file) + mad_recv_wc->mad_len;
225	packet->mad.hdr.qpn	   = cpu_to_be32(mad_recv_wc->wc->src_qp);
226	packet->mad.hdr.lid	   = cpu_to_be16(mad_recv_wc->wc->slid);
227	packet->mad.hdr.sl	   = mad_recv_wc->wc->sl;
228	packet->mad.hdr.path_bits  = mad_recv_wc->wc->dlid_path_bits;
229	packet->mad.hdr.pkey_index = mad_recv_wc->wc->pkey_index;
230	packet->mad.hdr.grh_present = !!(mad_recv_wc->wc->wc_flags & IB_WC_GRH);
231	if (packet->mad.hdr.grh_present) {
232		struct ib_ah_attr ah_attr;
233
234		ib_init_ah_from_wc(agent->device, agent->port_num,
235				   mad_recv_wc->wc, mad_recv_wc->recv_buf.grh,
236				   &ah_attr);
237
238		packet->mad.hdr.gid_index = ah_attr.grh.sgid_index;
239		packet->mad.hdr.hop_limit = ah_attr.grh.hop_limit;
240		packet->mad.hdr.traffic_class = ah_attr.grh.traffic_class;
241		memcpy(packet->mad.hdr.gid, &ah_attr.grh.dgid, 16);
242		packet->mad.hdr.flow_label = cpu_to_be32(ah_attr.grh.flow_label);
243	}
244
245	if (queue_packet(file, agent, packet))
246		goto err2;
247	return;
248
249err2:
250	kfree(packet);
251err1:
252	ib_free_recv_mad(mad_recv_wc);
253}
254
255static ssize_t copy_recv_mad(struct ib_umad_file *file, char __user *buf,
256			     struct ib_umad_packet *packet, size_t count)
257{
258	struct ib_mad_recv_buf *recv_buf;
259	int left, seg_payload, offset, max_seg_payload;
260
261	/* We need enough room to copy the first (or only) MAD segment. */
262	recv_buf = &packet->recv_wc->recv_buf;
263	if ((packet->length <= sizeof (*recv_buf->mad) &&
264	     count < hdr_size(file) + packet->length) ||
265	    (packet->length > sizeof (*recv_buf->mad) &&
266	     count < hdr_size(file) + sizeof (*recv_buf->mad)))
267		return -EINVAL;
268
269	if (copy_to_user(buf, &packet->mad, hdr_size(file)))
270		return -EFAULT;
271
272	buf += hdr_size(file);
273	seg_payload = min_t(int, packet->length, sizeof (*recv_buf->mad));
274	if (copy_to_user(buf, recv_buf->mad, seg_payload))
275		return -EFAULT;
276
277	if (seg_payload < packet->length) {
278		/*
279		 * Multipacket RMPP MAD message. Copy remainder of message.
280		 * Note that last segment may have a shorter payload.
281		 */
282		if (count < hdr_size(file) + packet->length) {
283			/*
284			 * The buffer is too small, return the first RMPP segment,
285			 * which includes the RMPP message length.
286			 */
287			return -ENOSPC;
288		}
289		offset = ib_get_mad_data_offset(recv_buf->mad->mad_hdr.mgmt_class);
290		max_seg_payload = sizeof (struct ib_mad) - offset;
291
292		for (left = packet->length - seg_payload, buf += seg_payload;
293		     left; left -= seg_payload, buf += seg_payload) {
294			recv_buf = container_of(recv_buf->list.next,
295						struct ib_mad_recv_buf, list);
296			seg_payload = min(left, max_seg_payload);
297			if (copy_to_user(buf, ((void *) recv_buf->mad) + offset,
298					 seg_payload))
299				return -EFAULT;
300		}
301	}
302	return hdr_size(file) + packet->length;
303}
304
305static ssize_t copy_send_mad(struct ib_umad_file *file, char __user *buf,
306			     struct ib_umad_packet *packet, size_t count)
307{
308	ssize_t size = hdr_size(file) + packet->length;
309
310	if (count < size)
311		return -EINVAL;
312
313	if (copy_to_user(buf, &packet->mad, hdr_size(file)))
314		return -EFAULT;
315
316	buf += hdr_size(file);
317
318	if (copy_to_user(buf, packet->mad.data, packet->length))
319		return -EFAULT;
320
321	return size;
322}
323
324static ssize_t ib_umad_read(struct file *filp, char __user *buf,
325			    size_t count, loff_t *pos)
326{
327	struct ib_umad_file *file = filp->private_data;
328	struct ib_umad_packet *packet;
329	ssize_t ret;
330
331	if (count < hdr_size(file))
332		return -EINVAL;
333
334	mutex_lock(&file->mutex);
335
336	while (list_empty(&file->recv_list)) {
337		mutex_unlock(&file->mutex);
338
339		if (filp->f_flags & O_NONBLOCK)
340			return -EAGAIN;
341
342		if (wait_event_interruptible(file->recv_wait,
343					     !list_empty(&file->recv_list)))
344			return -ERESTARTSYS;
345
346		mutex_lock(&file->mutex);
347	}
348
349	packet = list_entry(file->recv_list.next, struct ib_umad_packet, list);
350	list_del(&packet->list);
351
352	mutex_unlock(&file->mutex);
353
354	if (packet->recv_wc)
355		ret = copy_recv_mad(file, buf, packet, count);
356	else
357		ret = copy_send_mad(file, buf, packet, count);
358
359	if (ret < 0) {
360		/* Requeue packet */
361		mutex_lock(&file->mutex);
362		list_add(&packet->list, &file->recv_list);
363		mutex_unlock(&file->mutex);
364	} else {
365		if (packet->recv_wc)
366			ib_free_recv_mad(packet->recv_wc);
367		kfree(packet);
368	}
369	return ret;
370}
371
372static int copy_rmpp_mad(struct ib_mad_send_buf *msg, const char __user *buf)
373{
374	int left, seg;
375
376	/* Copy class specific header */
377	if ((msg->hdr_len > IB_MGMT_RMPP_HDR) &&
378	    copy_from_user(msg->mad + IB_MGMT_RMPP_HDR, buf + IB_MGMT_RMPP_HDR,
379			   msg->hdr_len - IB_MGMT_RMPP_HDR))
380		return -EFAULT;
381
382	/* All headers are in place.  Copy data segments. */
383	for (seg = 1, left = msg->data_len, buf += msg->hdr_len; left > 0;
384	     seg++, left -= msg->seg_size, buf += msg->seg_size) {
385		if (copy_from_user(ib_get_rmpp_segment(msg, seg), buf,
386				   min(left, msg->seg_size)))
387			return -EFAULT;
388	}
389	return 0;
390}
391
392static int same_destination(struct ib_user_mad_hdr *hdr1,
393			    struct ib_user_mad_hdr *hdr2)
394{
395	if (!hdr1->grh_present && !hdr2->grh_present)
396	   return (hdr1->lid == hdr2->lid);
397
398	if (hdr1->grh_present && hdr2->grh_present)
399	   return !memcmp(hdr1->gid, hdr2->gid, 16);
400
401	return 0;
402}
403
404static int is_duplicate(struct ib_umad_file *file,
405			struct ib_umad_packet *packet)
406{
407	struct ib_umad_packet *sent_packet;
408	struct ib_mad_hdr *sent_hdr, *hdr;
409
410	hdr = (struct ib_mad_hdr *) packet->mad.data;
411	list_for_each_entry(sent_packet, &file->send_list, list) {
412		sent_hdr = (struct ib_mad_hdr *) sent_packet->mad.data;
413
414		if ((hdr->tid != sent_hdr->tid) ||
415		    (hdr->mgmt_class != sent_hdr->mgmt_class))
416			continue;
417
418		/*
419		 * No need to be overly clever here.  If two new operations have
420		 * the same TID, reject the second as a duplicate.  This is more
421		 * restrictive than required by the spec.
422		 */
423		if (!ib_response_mad((struct ib_mad *) hdr)) {
424			if (!ib_response_mad((struct ib_mad *) sent_hdr))
425				return 1;
426			continue;
427		} else if (!ib_response_mad((struct ib_mad *) sent_hdr))
428			continue;
429
430		if (same_destination(&packet->mad.hdr, &sent_packet->mad.hdr))
431			return 1;
432	}
433
434	return 0;
435}
436
437static ssize_t ib_umad_write(struct file *filp, const char __user *buf,
438			     size_t count, loff_t *pos)
439{
440	struct ib_umad_file *file = filp->private_data;
441	struct ib_umad_packet *packet;
442	struct ib_mad_agent *agent;
443	struct ib_ah_attr ah_attr;
444	struct ib_ah *ah;
445	struct ib_rmpp_mad *rmpp_mad;
446	__be64 *tid;
447	int ret, data_len, hdr_len, copy_offset, rmpp_active;
448
449	if (count < hdr_size(file) + IB_MGMT_RMPP_HDR)
450		return -EINVAL;
451
452	packet = kzalloc(sizeof *packet + IB_MGMT_RMPP_HDR, GFP_KERNEL);
453	if (!packet)
454		return -ENOMEM;
455
456	if (copy_from_user(&packet->mad, buf, hdr_size(file))) {
457		ret = -EFAULT;
458		goto err;
459	}
460
461	if (packet->mad.hdr.id < 0 ||
462	    packet->mad.hdr.id >= IB_UMAD_MAX_AGENTS) {
463		ret = -EINVAL;
464		goto err;
465	}
466
467	buf += hdr_size(file);
468
469	if (copy_from_user(packet->mad.data, buf, IB_MGMT_RMPP_HDR)) {
470		ret = -EFAULT;
471		goto err;
472	}
473
474	mutex_lock(&file->mutex);
475
476	agent = __get_agent(file, packet->mad.hdr.id);
477	if (!agent) {
478		ret = -EINVAL;
479		goto err_up;
480	}
481
482	memset(&ah_attr, 0, sizeof ah_attr);
483	ah_attr.dlid          = be16_to_cpu(packet->mad.hdr.lid);
484	ah_attr.sl            = packet->mad.hdr.sl;
485	ah_attr.src_path_bits = packet->mad.hdr.path_bits;
486	ah_attr.port_num      = file->port->port_num;
487	if (packet->mad.hdr.grh_present) {
488		ah_attr.ah_flags = IB_AH_GRH;
489		memcpy(ah_attr.grh.dgid.raw, packet->mad.hdr.gid, 16);
490		ah_attr.grh.sgid_index	   = packet->mad.hdr.gid_index;
491		ah_attr.grh.flow_label	   = be32_to_cpu(packet->mad.hdr.flow_label);
492		ah_attr.grh.hop_limit	   = packet->mad.hdr.hop_limit;
493		ah_attr.grh.traffic_class  = packet->mad.hdr.traffic_class;
494	}
495
496	ah = ib_create_ah(agent->qp->pd, &ah_attr);
497	if (IS_ERR(ah)) {
498		ret = PTR_ERR(ah);
499		goto err_up;
500	}
501
502	rmpp_mad = (struct ib_rmpp_mad *) packet->mad.data;
503	hdr_len = ib_get_mad_data_offset(rmpp_mad->mad_hdr.mgmt_class);
504	if (!ib_is_mad_class_rmpp(rmpp_mad->mad_hdr.mgmt_class)) {
505		copy_offset = IB_MGMT_MAD_HDR;
506		rmpp_active = 0;
507	} else {
508		copy_offset = IB_MGMT_RMPP_HDR;
509		rmpp_active = ib_get_rmpp_flags(&rmpp_mad->rmpp_hdr) &
510			      IB_MGMT_RMPP_FLAG_ACTIVE;
511	}
512
513	data_len = count - hdr_size(file) - hdr_len;
514	packet->msg = ib_create_send_mad(agent,
515					 be32_to_cpu(packet->mad.hdr.qpn),
516					 packet->mad.hdr.pkey_index, rmpp_active,
517					 hdr_len, data_len, GFP_KERNEL);
518	if (IS_ERR(packet->msg)) {
519		ret = PTR_ERR(packet->msg);
520		goto err_ah;
521	}
522
523	packet->msg->ah		= ah;
524	packet->msg->timeout_ms = packet->mad.hdr.timeout_ms;
525	packet->msg->retries	= packet->mad.hdr.retries;
526	packet->msg->context[0] = packet;
527
528	/* Copy MAD header.  Any RMPP header is already in place. */
529	memcpy(packet->msg->mad, packet->mad.data, IB_MGMT_MAD_HDR);
530
531	if (!rmpp_active) {
532		if (copy_from_user(packet->msg->mad + copy_offset,
533				   buf + copy_offset,
534				   hdr_len + data_len - copy_offset)) {
535			ret = -EFAULT;
536			goto err_msg;
537		}
538	} else {
539		ret = copy_rmpp_mad(packet->msg, buf);
540		if (ret)
541			goto err_msg;
542	}
543
544	/*
545	 * Set the high-order part of the transaction ID to make MADs from
546	 * different agents unique, and allow routing responses back to the
547	 * original requestor.
548	 */
549	if (!ib_response_mad(packet->msg->mad)) {
550		tid = &((struct ib_mad_hdr *) packet->msg->mad)->tid;
551		*tid = cpu_to_be64(((u64) agent->hi_tid) << 32 |
552				   (be64_to_cpup(tid) & 0xffffffff));
553		rmpp_mad->mad_hdr.tid = *tid;
554	}
555
556	spin_lock_irq(&file->send_lock);
557	ret = is_duplicate(file, packet);
558	if (!ret)
559		list_add_tail(&packet->list, &file->send_list);
560	spin_unlock_irq(&file->send_lock);
561	if (ret) {
562		ret = -EINVAL;
563		goto err_msg;
564	}
565
566	ret = ib_post_send_mad(packet->msg, NULL);
567	if (ret)
568		goto err_send;
569
570	mutex_unlock(&file->mutex);
571	return count;
572
573err_send:
574	dequeue_send(file, packet);
575err_msg:
576	ib_free_send_mad(packet->msg);
577err_ah:
578	ib_destroy_ah(ah);
579err_up:
580	mutex_unlock(&file->mutex);
581err:
582	kfree(packet);
583	return ret;
584}
585
586static unsigned int ib_umad_poll(struct file *filp, struct poll_table_struct *wait)
587{
588	struct ib_umad_file *file = filp->private_data;
589
590	/* we will always be able to post a MAD send */
591	unsigned int mask = POLLOUT | POLLWRNORM;
592
593	poll_wait(filp, &file->recv_wait, wait);
594
595	if (!list_empty(&file->recv_list))
596		mask |= POLLIN | POLLRDNORM;
597
598	return mask;
599}
600
601static int ib_umad_reg_agent(struct ib_umad_file *file, void __user *arg,
602			     int compat_method_mask)
603{
604	struct ib_user_mad_reg_req ureq;
605	struct ib_mad_reg_req req;
606	struct ib_mad_agent *agent = NULL;
607	int agent_id;
608	int ret;
609
610	mutex_lock(&file->port->file_mutex);
611	mutex_lock(&file->mutex);
612
613	if (!file->port->ib_dev) {
614		ret = -EPIPE;
615		goto out;
616	}
617
618	if (copy_from_user(&ureq, arg, sizeof ureq)) {
619		ret = -EFAULT;
620		goto out;
621	}
622
623	if (ureq.qpn != 0 && ureq.qpn != 1) {
624		ret = -EINVAL;
625		goto out;
626	}
627
628	for (agent_id = 0; agent_id < IB_UMAD_MAX_AGENTS; ++agent_id)
629		if (!__get_agent(file, agent_id))
630			goto found;
631
632	ret = -ENOMEM;
633	goto out;
634
635found:
636	if (ureq.mgmt_class) {
637		req.mgmt_class         = ureq.mgmt_class;
638		req.mgmt_class_version = ureq.mgmt_class_version;
639		memcpy(req.oui, ureq.oui, sizeof req.oui);
640
641		if (compat_method_mask) {
642			u32 *umm = (u32 *) ureq.method_mask;
643			int i;
644
645			for (i = 0; i < BITS_TO_LONGS(IB_MGMT_MAX_METHODS); ++i)
646				req.method_mask[i] =
647					umm[i * 2] | ((u64) umm[i * 2 + 1] << 32);
648		} else
649			memcpy(req.method_mask, ureq.method_mask,
650			       sizeof req.method_mask);
651	}
652
653	agent = ib_register_mad_agent(file->port->ib_dev, file->port->port_num,
654				      ureq.qpn ? IB_QPT_GSI : IB_QPT_SMI,
655				      ureq.mgmt_class ? &req : NULL,
656				      ureq.rmpp_version,
657				      send_handler, recv_handler, file);
658	if (IS_ERR(agent)) {
659		ret = PTR_ERR(agent);
660		agent = NULL;
661		goto out;
662	}
663
664	if (put_user(agent_id,
665		     (u32 __user *) (arg + offsetof(struct ib_user_mad_reg_req, id)))) {
666		ret = -EFAULT;
667		goto out;
668	}
669
670	if (!file->already_used) {
671		file->already_used = 1;
672		if (!file->use_pkey_index) {
673			printk(KERN_WARNING "user_mad: process %s did not enable "
674			       "P_Key index support.\n", current->comm);
675			printk(KERN_WARNING "user_mad:   Documentation/infiniband/user_mad.txt "
676			       "has info on the new ABI.\n");
677		}
678	}
679
680	file->agent[agent_id] = agent;
681	ret = 0;
682
683out:
684	mutex_unlock(&file->mutex);
685
686	if (ret && agent)
687		ib_unregister_mad_agent(agent);
688
689	mutex_unlock(&file->port->file_mutex);
690
691	return ret;
692}
693
694static int ib_umad_unreg_agent(struct ib_umad_file *file, u32 __user *arg)
695{
696	struct ib_mad_agent *agent = NULL;
697	u32 id;
698	int ret = 0;
699
700	if (get_user(id, arg))
701		return -EFAULT;
702
703	mutex_lock(&file->port->file_mutex);
704	mutex_lock(&file->mutex);
705
706	if (id < 0 || id >= IB_UMAD_MAX_AGENTS || !__get_agent(file, id)) {
707		ret = -EINVAL;
708		goto out;
709	}
710
711	agent = file->agent[id];
712	file->agent[id] = NULL;
713
714out:
715	mutex_unlock(&file->mutex);
716
717	if (agent)
718		ib_unregister_mad_agent(agent);
719
720	mutex_unlock(&file->port->file_mutex);
721
722	return ret;
723}
724
725static long ib_umad_enable_pkey(struct ib_umad_file *file)
726{
727	int ret = 0;
728
729	mutex_lock(&file->mutex);
730	if (file->already_used)
731		ret = -EINVAL;
732	else
733		file->use_pkey_index = 1;
734	mutex_unlock(&file->mutex);
735
736	return ret;
737}
738
739static long ib_umad_ioctl(struct file *filp, unsigned int cmd,
740			  unsigned long arg)
741{
742	switch (cmd) {
743	case IB_USER_MAD_REGISTER_AGENT:
744		return ib_umad_reg_agent(filp->private_data, (void __user *) arg, 0);
745	case IB_USER_MAD_UNREGISTER_AGENT:
746		return ib_umad_unreg_agent(filp->private_data, (__u32 __user *) arg);
747	case IB_USER_MAD_ENABLE_PKEY:
748		return ib_umad_enable_pkey(filp->private_data);
749	default:
750		return -ENOIOCTLCMD;
751	}
752}
753
754#ifdef CONFIG_COMPAT
755static long ib_umad_compat_ioctl(struct file *filp, unsigned int cmd,
756				 unsigned long arg)
757{
758	switch (cmd) {
759	case IB_USER_MAD_REGISTER_AGENT:
760		return ib_umad_reg_agent(filp->private_data, compat_ptr(arg), 1);
761	case IB_USER_MAD_UNREGISTER_AGENT:
762		return ib_umad_unreg_agent(filp->private_data, compat_ptr(arg));
763	case IB_USER_MAD_ENABLE_PKEY:
764		return ib_umad_enable_pkey(filp->private_data);
765	default:
766		return -ENOIOCTLCMD;
767	}
768}
769#endif
770
771/*
772 * ib_umad_open() does not need the BKL:
773 *
774 *  - the ib_umad_port structures are properly reference counted, and
775 *    everything else is purely local to the file being created, so
776 *    races against other open calls are not a problem;
777 *  - the ioctl method does not affect any global state outside of the
778 *    file structure being operated on;
779 */
780static int ib_umad_open(struct inode *inode, struct file *filp)
781{
782	struct ib_umad_port *port;
783	struct ib_umad_file *file;
784	int ret;
785
786	port = container_of(inode->i_cdev, struct ib_umad_port, cdev);
787	if (port)
788		kref_get(&port->umad_dev->ref);
789	else
790		return -ENXIO;
791
792	mutex_lock(&port->file_mutex);
793
794	if (!port->ib_dev) {
795		ret = -ENXIO;
796		goto out;
797	}
798
799	file = kzalloc(sizeof *file, GFP_KERNEL);
800	if (!file) {
801		kref_put(&port->umad_dev->ref, ib_umad_release_dev);
802		ret = -ENOMEM;
803		goto out;
804	}
805
806	mutex_init(&file->mutex);
807	spin_lock_init(&file->send_lock);
808	INIT_LIST_HEAD(&file->recv_list);
809	INIT_LIST_HEAD(&file->send_list);
810	init_waitqueue_head(&file->recv_wait);
811
812	file->port = port;
813	filp->private_data = file;
814
815	list_add_tail(&file->port_list, &port->file_list);
816
817	ret = nonseekable_open(inode, filp);
818
819out:
820	mutex_unlock(&port->file_mutex);
821	return ret;
822}
823
824static int ib_umad_close(struct inode *inode, struct file *filp)
825{
826	struct ib_umad_file *file = filp->private_data;
827	struct ib_umad_device *dev = file->port->umad_dev;
828	struct ib_umad_packet *packet, *tmp;
829	int already_dead;
830	int i;
831
832	mutex_lock(&file->port->file_mutex);
833	mutex_lock(&file->mutex);
834
835	already_dead = file->agents_dead;
836	file->agents_dead = 1;
837
838	list_for_each_entry_safe(packet, tmp, &file->recv_list, list) {
839		if (packet->recv_wc)
840			ib_free_recv_mad(packet->recv_wc);
841		kfree(packet);
842	}
843
844	list_del(&file->port_list);
845
846	mutex_unlock(&file->mutex);
847
848	if (!already_dead)
849		for (i = 0; i < IB_UMAD_MAX_AGENTS; ++i)
850			if (file->agent[i])
851				ib_unregister_mad_agent(file->agent[i]);
852
853	mutex_unlock(&file->port->file_mutex);
854
855	kfree(file);
856	kref_put(&dev->ref, ib_umad_release_dev);
857
858	return 0;
859}
860
861static const struct file_operations umad_fops = {
862	.owner		= THIS_MODULE,
863	.read		= ib_umad_read,
864	.write		= ib_umad_write,
865	.poll		= ib_umad_poll,
866	.unlocked_ioctl = ib_umad_ioctl,
867#ifdef CONFIG_COMPAT
868	.compat_ioctl	= ib_umad_compat_ioctl,
869#endif
870	.open		= ib_umad_open,
871	.release	= ib_umad_close,
872	.llseek		= no_llseek,
873};
874
875static int ib_umad_sm_open(struct inode *inode, struct file *filp)
876{
877	struct ib_umad_port *port;
878	struct ib_port_modify props = {
879		.set_port_cap_mask = IB_PORT_SM
880	};
881	int ret;
882
883	port = container_of(inode->i_cdev, struct ib_umad_port, sm_cdev);
884	if (port)
885		kref_get(&port->umad_dev->ref);
886	else
887		return -ENXIO;
888
889	if (filp->f_flags & O_NONBLOCK) {
890		if (down_trylock(&port->sm_sem)) {
891			ret = -EAGAIN;
892			goto fail;
893		}
894	} else {
895		if (down_interruptible(&port->sm_sem)) {
896			ret = -ERESTARTSYS;
897			goto fail;
898		}
899	}
900
901	ret = ib_modify_port(port->ib_dev, port->port_num, 0, &props);
902	if (ret) {
903		up(&port->sm_sem);
904		goto fail;
905	}
906
907	filp->private_data = port;
908
909	return nonseekable_open(inode, filp);
910
911fail:
912	kref_put(&port->umad_dev->ref, ib_umad_release_dev);
913	return ret;
914}
915
916static int ib_umad_sm_close(struct inode *inode, struct file *filp)
917{
918	struct ib_umad_port *port = filp->private_data;
919	struct ib_port_modify props = {
920		.clr_port_cap_mask = IB_PORT_SM
921	};
922	int ret = 0;
923
924	mutex_lock(&port->file_mutex);
925	if (port->ib_dev)
926		ret = ib_modify_port(port->ib_dev, port->port_num, 0, &props);
927	mutex_unlock(&port->file_mutex);
928
929	up(&port->sm_sem);
930
931	kref_put(&port->umad_dev->ref, ib_umad_release_dev);
932
933	return ret;
934}
935
936static const struct file_operations umad_sm_fops = {
937	.owner	 = THIS_MODULE,
938	.open	 = ib_umad_sm_open,
939	.release = ib_umad_sm_close,
940	.llseek	 = no_llseek,
941};
942
943static struct ib_client umad_client = {
944	.name   = "umad",
945	.add    = ib_umad_add_one,
946	.remove = ib_umad_remove_one
947};
948
949static ssize_t show_ibdev(struct device *dev, struct device_attribute *attr,
950			  char *buf)
951{
952	struct ib_umad_port *port = dev_get_drvdata(dev);
953
954	if (!port)
955		return -ENODEV;
956
957	return sprintf(buf, "%s\n", port->ib_dev->name);
958}
959static DEVICE_ATTR(ibdev, S_IRUGO, show_ibdev, NULL);
960
961static ssize_t show_port(struct device *dev, struct device_attribute *attr,
962			 char *buf)
963{
964	struct ib_umad_port *port = dev_get_drvdata(dev);
965
966	if (!port)
967		return -ENODEV;
968
969	return sprintf(buf, "%d\n", port->port_num);
970}
971static DEVICE_ATTR(port, S_IRUGO, show_port, NULL);
972
973static CLASS_ATTR_STRING(abi_version, S_IRUGO,
974			 __stringify(IB_USER_MAD_ABI_VERSION));
975
976static dev_t overflow_maj;
977static DECLARE_BITMAP(overflow_map, IB_UMAD_MAX_PORTS);
978static int find_overflow_devnum(void)
979{
980	int ret;
981
982	if (!overflow_maj) {
983		ret = alloc_chrdev_region(&overflow_maj, 0, IB_UMAD_MAX_PORTS * 2,
984					  "infiniband_mad");
985		if (ret) {
986			printk(KERN_ERR "user_mad: couldn't register dynamic device number\n");
987			return ret;
988		}
989	}
990
991	ret = find_first_zero_bit(overflow_map, IB_UMAD_MAX_PORTS);
992	if (ret >= IB_UMAD_MAX_PORTS)
993		return -1;
994
995	return ret;
996}
997
998static int ib_umad_init_port(struct ib_device *device, int port_num,
999			     struct ib_umad_port *port)
1000{
1001	int devnum;
1002	dev_t base;
1003
1004	spin_lock(&port_lock);
1005	devnum = find_first_zero_bit(dev_map, IB_UMAD_MAX_PORTS);
1006	if (devnum >= IB_UMAD_MAX_PORTS) {
1007		spin_unlock(&port_lock);
1008		devnum = find_overflow_devnum();
1009		if (devnum < 0)
1010			return -1;
1011
1012		spin_lock(&port_lock);
1013		port->dev_num = devnum + IB_UMAD_MAX_PORTS;
1014		base = devnum + overflow_maj;
1015		set_bit(devnum, overflow_map);
1016	} else {
1017		port->dev_num = devnum;
1018		base = devnum + base_dev;
1019		set_bit(devnum, dev_map);
1020	}
1021	spin_unlock(&port_lock);
1022
1023	port->ib_dev   = device;
1024	port->port_num = port_num;
1025	init_MUTEX(&port->sm_sem);
1026	mutex_init(&port->file_mutex);
1027	INIT_LIST_HEAD(&port->file_list);
1028
1029	cdev_init(&port->cdev, &umad_fops);
1030	port->cdev.owner = THIS_MODULE;
1031	kobject_set_name(&port->cdev.kobj, "umad%d", port->dev_num);
1032	if (cdev_add(&port->cdev, base, 1))
1033		goto err_cdev;
1034
1035	port->dev = device_create(umad_class, device->dma_device,
1036				  port->cdev.dev, port,
1037				  "umad%d", port->dev_num);
1038	if (IS_ERR(port->dev))
1039		goto err_cdev;
1040
1041	if (device_create_file(port->dev, &dev_attr_ibdev))
1042		goto err_dev;
1043	if (device_create_file(port->dev, &dev_attr_port))
1044		goto err_dev;
1045
1046	base += IB_UMAD_MAX_PORTS;
1047	cdev_init(&port->sm_cdev, &umad_sm_fops);
1048	port->sm_cdev.owner = THIS_MODULE;
1049	kobject_set_name(&port->sm_cdev.kobj, "issm%d", port->dev_num);
1050	if (cdev_add(&port->sm_cdev, base, 1))
1051		goto err_sm_cdev;
1052
1053	port->sm_dev = device_create(umad_class, device->dma_device,
1054				     port->sm_cdev.dev, port,
1055				     "issm%d", port->dev_num);
1056	if (IS_ERR(port->sm_dev))
1057		goto err_sm_cdev;
1058
1059	if (device_create_file(port->sm_dev, &dev_attr_ibdev))
1060		goto err_sm_dev;
1061	if (device_create_file(port->sm_dev, &dev_attr_port))
1062		goto err_sm_dev;
1063
1064	return 0;
1065
1066err_sm_dev:
1067	device_destroy(umad_class, port->sm_cdev.dev);
1068
1069err_sm_cdev:
1070	cdev_del(&port->sm_cdev);
1071
1072err_dev:
1073	device_destroy(umad_class, port->cdev.dev);
1074
1075err_cdev:
1076	cdev_del(&port->cdev);
1077	if (port->dev_num < IB_UMAD_MAX_PORTS)
1078		clear_bit(devnum, dev_map);
1079	else
1080		clear_bit(devnum, overflow_map);
1081
1082	return -1;
1083}
1084
1085static void ib_umad_kill_port(struct ib_umad_port *port)
1086{
1087	struct ib_umad_file *file;
1088	int already_dead;
1089	int id;
1090
1091	dev_set_drvdata(port->dev,    NULL);
1092	dev_set_drvdata(port->sm_dev, NULL);
1093
1094	device_destroy(umad_class, port->cdev.dev);
1095	device_destroy(umad_class, port->sm_cdev.dev);
1096
1097	cdev_del(&port->cdev);
1098	cdev_del(&port->sm_cdev);
1099
1100	mutex_lock(&port->file_mutex);
1101
1102	port->ib_dev = NULL;
1103
1104	list_for_each_entry(file, &port->file_list, port_list) {
1105		mutex_lock(&file->mutex);
1106		already_dead = file->agents_dead;
1107		file->agents_dead = 1;
1108		mutex_unlock(&file->mutex);
1109
1110		for (id = 0; id < IB_UMAD_MAX_AGENTS; ++id)
1111			if (file->agent[id])
1112				ib_unregister_mad_agent(file->agent[id]);
1113	}
1114
1115	mutex_unlock(&port->file_mutex);
1116
1117	if (port->dev_num < IB_UMAD_MAX_PORTS)
1118		clear_bit(port->dev_num, dev_map);
1119	else
1120		clear_bit(port->dev_num - IB_UMAD_MAX_PORTS, overflow_map);
1121}
1122
1123static void ib_umad_add_one(struct ib_device *device)
1124{
1125	struct ib_umad_device *umad_dev;
1126	int s, e, i;
1127
1128	if (rdma_node_get_transport(device->node_type) != RDMA_TRANSPORT_IB)
1129		return;
1130
1131	if (device->node_type == RDMA_NODE_IB_SWITCH)
1132		s = e = 0;
1133	else {
1134		s = 1;
1135		e = device->phys_port_cnt;
1136	}
1137
1138	umad_dev = kzalloc(sizeof *umad_dev +
1139			   (e - s + 1) * sizeof (struct ib_umad_port),
1140			   GFP_KERNEL);
1141	if (!umad_dev)
1142		return;
1143
1144	kref_init(&umad_dev->ref);
1145
1146	umad_dev->start_port = s;
1147	umad_dev->end_port   = e;
1148
1149	for (i = s; i <= e; ++i) {
1150		umad_dev->port[i - s].umad_dev = umad_dev;
1151
1152		if (ib_umad_init_port(device, i, &umad_dev->port[i - s]))
1153			goto err;
1154	}
1155
1156	ib_set_client_data(device, &umad_client, umad_dev);
1157
1158	return;
1159
1160err:
1161	while (--i >= s)
1162		ib_umad_kill_port(&umad_dev->port[i - s]);
1163
1164	kref_put(&umad_dev->ref, ib_umad_release_dev);
1165}
1166
1167static void ib_umad_remove_one(struct ib_device *device)
1168{
1169	struct ib_umad_device *umad_dev = ib_get_client_data(device, &umad_client);
1170	int i;
1171
1172	if (!umad_dev)
1173		return;
1174
1175	for (i = 0; i <= umad_dev->end_port - umad_dev->start_port; ++i)
1176		ib_umad_kill_port(&umad_dev->port[i]);
1177
1178	kref_put(&umad_dev->ref, ib_umad_release_dev);
1179}
1180
1181static int __init ib_umad_init(void)
1182{
1183	int ret;
1184
1185	ret = register_chrdev_region(base_dev, IB_UMAD_MAX_PORTS * 2,
1186				     "infiniband_mad");
1187	if (ret) {
1188		printk(KERN_ERR "user_mad: couldn't register device number\n");
1189		goto out;
1190	}
1191
1192	umad_class = class_create(THIS_MODULE, "infiniband_mad");
1193	if (IS_ERR(umad_class)) {
1194		ret = PTR_ERR(umad_class);
1195		printk(KERN_ERR "user_mad: couldn't create class infiniband_mad\n");
1196		goto out_chrdev;
1197	}
1198
1199	ret = class_create_file(umad_class, &class_attr_abi_version.attr);
1200	if (ret) {
1201		printk(KERN_ERR "user_mad: couldn't create abi_version attribute\n");
1202		goto out_class;
1203	}
1204
1205	ret = ib_register_client(&umad_client);
1206	if (ret) {
1207		printk(KERN_ERR "user_mad: couldn't register ib_umad client\n");
1208		goto out_class;
1209	}
1210
1211	return 0;
1212
1213out_class:
1214	class_destroy(umad_class);
1215
1216out_chrdev:
1217	unregister_chrdev_region(base_dev, IB_UMAD_MAX_PORTS * 2);
1218
1219out:
1220	return ret;
1221}
1222
1223static void __exit ib_umad_cleanup(void)
1224{
1225	ib_unregister_client(&umad_client);
1226	class_destroy(umad_class);
1227	unregister_chrdev_region(base_dev, IB_UMAD_MAX_PORTS * 2);
1228	if (overflow_maj)
1229		unregister_chrdev_region(overflow_maj, IB_UMAD_MAX_PORTS * 2);
1230}
1231
1232module_init(ib_umad_init);
1233module_exit(ib_umad_cleanup);
1234