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v4.10.11
  1/*
  2 * Copyright (c) 2006 Oracle.  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/kernel.h>
 34#include <linux/in.h>
 35#include <linux/if.h>
 36#include <linux/netdevice.h>
 37#include <linux/inetdevice.h>
 38#include <linux/if_arp.h>
 39#include <linux/delay.h>
 40#include <linux/slab.h>
 41#include <linux/module.h>
 42
 43#include "rds_single_path.h"
 44#include "rds.h"
 45#include "ib.h"
 46#include "ib_mr.h"
 47
 48unsigned int rds_ib_mr_1m_pool_size = RDS_MR_1M_POOL_SIZE;
 49unsigned int rds_ib_mr_8k_pool_size = RDS_MR_8K_POOL_SIZE;
 50unsigned int rds_ib_retry_count = RDS_IB_DEFAULT_RETRY_COUNT;
 51
 52module_param(rds_ib_mr_1m_pool_size, int, 0444);
 53MODULE_PARM_DESC(rds_ib_mr_1m_pool_size, " Max number of 1M mr per HCA");
 54module_param(rds_ib_mr_8k_pool_size, int, 0444);
 55MODULE_PARM_DESC(rds_ib_mr_8k_pool_size, " Max number of 8K mr per HCA");
 56module_param(rds_ib_retry_count, int, 0444);
 57MODULE_PARM_DESC(rds_ib_retry_count, " Number of hw retries before reporting an error");
 58
 59/*
 60 * we have a clumsy combination of RCU and a rwsem protecting this list
 61 * because it is used both in the get_mr fast path and while blocking in
 62 * the FMR flushing path.
 63 */
 64DECLARE_RWSEM(rds_ib_devices_lock);
 65struct list_head rds_ib_devices;
 66
 67/* NOTE: if also grabbing ibdev lock, grab this first */
 68DEFINE_SPINLOCK(ib_nodev_conns_lock);
 69LIST_HEAD(ib_nodev_conns);
 70
 71static void rds_ib_nodev_connect(void)
 72{
 73	struct rds_ib_connection *ic;
 74
 75	spin_lock(&ib_nodev_conns_lock);
 76	list_for_each_entry(ic, &ib_nodev_conns, ib_node)
 77		rds_conn_connect_if_down(ic->conn);
 78	spin_unlock(&ib_nodev_conns_lock);
 79}
 80
 81static void rds_ib_dev_shutdown(struct rds_ib_device *rds_ibdev)
 82{
 83	struct rds_ib_connection *ic;
 84	unsigned long flags;
 85
 86	spin_lock_irqsave(&rds_ibdev->spinlock, flags);
 87	list_for_each_entry(ic, &rds_ibdev->conn_list, ib_node)
 88		rds_conn_drop(ic->conn);
 89	spin_unlock_irqrestore(&rds_ibdev->spinlock, flags);
 90}
 91
 92/*
 93 * rds_ib_destroy_mr_pool() blocks on a few things and mrs drop references
 94 * from interrupt context so we push freing off into a work struct in krdsd.
 95 */
 96static void rds_ib_dev_free(struct work_struct *work)
 97{
 98	struct rds_ib_ipaddr *i_ipaddr, *i_next;
 99	struct rds_ib_device *rds_ibdev = container_of(work,
100					struct rds_ib_device, free_work);
101
102	if (rds_ibdev->mr_8k_pool)
103		rds_ib_destroy_mr_pool(rds_ibdev->mr_8k_pool);
104	if (rds_ibdev->mr_1m_pool)
105		rds_ib_destroy_mr_pool(rds_ibdev->mr_1m_pool);
106	if (rds_ibdev->pd)
107		ib_dealloc_pd(rds_ibdev->pd);
108
109	list_for_each_entry_safe(i_ipaddr, i_next, &rds_ibdev->ipaddr_list, list) {
110		list_del(&i_ipaddr->list);
111		kfree(i_ipaddr);
112	}
113
114	kfree(rds_ibdev);
115}
116
117void rds_ib_dev_put(struct rds_ib_device *rds_ibdev)
118{
119	BUG_ON(atomic_read(&rds_ibdev->refcount) <= 0);
120	if (atomic_dec_and_test(&rds_ibdev->refcount))
121		queue_work(rds_wq, &rds_ibdev->free_work);
122}
123
124static void rds_ib_add_one(struct ib_device *device)
125{
126	struct rds_ib_device *rds_ibdev;
 
127
128	/* Only handle IB (no iWARP) devices */
129	if (device->node_type != RDMA_NODE_IB_CA)
130		return;
131
 
 
 
 
 
 
 
 
 
132	rds_ibdev = kzalloc_node(sizeof(struct rds_ib_device), GFP_KERNEL,
133				 ibdev_to_node(device));
134	if (!rds_ibdev)
135		return;
136
137	spin_lock_init(&rds_ibdev->spinlock);
138	atomic_set(&rds_ibdev->refcount, 1);
139	INIT_WORK(&rds_ibdev->free_work, rds_ib_dev_free);
140
141	rds_ibdev->max_wrs = device->attrs.max_qp_wr;
142	rds_ibdev->max_sge = min(device->attrs.max_sge, RDS_IB_MAX_SGE);
143
144	rds_ibdev->has_fr = (device->attrs.device_cap_flags &
145				  IB_DEVICE_MEM_MGT_EXTENSIONS);
146	rds_ibdev->has_fmr = (device->alloc_fmr && device->dealloc_fmr &&
147			    device->map_phys_fmr && device->unmap_fmr);
148	rds_ibdev->use_fastreg = (rds_ibdev->has_fr && !rds_ibdev->has_fmr);
149
150	rds_ibdev->fmr_max_remaps = device->attrs.max_map_per_fmr?: 32;
151	rds_ibdev->max_1m_mrs = device->attrs.max_mr ?
152		min_t(unsigned int, (device->attrs.max_mr / 2),
153		      rds_ib_mr_1m_pool_size) : rds_ib_mr_1m_pool_size;
154
155	rds_ibdev->max_8k_mrs = device->attrs.max_mr ?
156		min_t(unsigned int, ((device->attrs.max_mr / 2) * RDS_MR_8K_SCALE),
157		      rds_ib_mr_8k_pool_size) : rds_ib_mr_8k_pool_size;
158
159	rds_ibdev->max_initiator_depth = device->attrs.max_qp_init_rd_atom;
160	rds_ibdev->max_responder_resources = device->attrs.max_qp_rd_atom;
161
162	rds_ibdev->dev = device;
163	rds_ibdev->pd = ib_alloc_pd(device, 0);
164	if (IS_ERR(rds_ibdev->pd)) {
165		rds_ibdev->pd = NULL;
166		goto put_dev;
167	}
168
169	rds_ibdev->mr_1m_pool =
170		rds_ib_create_mr_pool(rds_ibdev, RDS_IB_MR_1M_POOL);
171	if (IS_ERR(rds_ibdev->mr_1m_pool)) {
172		rds_ibdev->mr_1m_pool = NULL;
173		goto put_dev;
174	}
175
176	rds_ibdev->mr_8k_pool =
177		rds_ib_create_mr_pool(rds_ibdev, RDS_IB_MR_8K_POOL);
178	if (IS_ERR(rds_ibdev->mr_8k_pool)) {
179		rds_ibdev->mr_8k_pool = NULL;
180		goto put_dev;
181	}
182
183	rdsdebug("RDS/IB: max_mr = %d, max_wrs = %d, max_sge = %d, fmr_max_remaps = %d, max_1m_mrs = %d, max_8k_mrs = %d\n",
184		 device->attrs.max_fmr, rds_ibdev->max_wrs, rds_ibdev->max_sge,
185		 rds_ibdev->fmr_max_remaps, rds_ibdev->max_1m_mrs,
186		 rds_ibdev->max_8k_mrs);
187
188	pr_info("RDS/IB: %s: %s supported and preferred\n",
189		device->name,
190		rds_ibdev->use_fastreg ? "FRMR" : "FMR");
191
192	INIT_LIST_HEAD(&rds_ibdev->ipaddr_list);
193	INIT_LIST_HEAD(&rds_ibdev->conn_list);
194
195	down_write(&rds_ib_devices_lock);
196	list_add_tail_rcu(&rds_ibdev->list, &rds_ib_devices);
197	up_write(&rds_ib_devices_lock);
198	atomic_inc(&rds_ibdev->refcount);
199
200	ib_set_client_data(device, &rds_ib_client, rds_ibdev);
201	atomic_inc(&rds_ibdev->refcount);
202
203	rds_ib_nodev_connect();
204
205put_dev:
206	rds_ib_dev_put(rds_ibdev);
 
 
207}
208
209/*
210 * New connections use this to find the device to associate with the
211 * connection.  It's not in the fast path so we're not concerned about the
212 * performance of the IB call.  (As of this writing, it uses an interrupt
213 * blocking spinlock to serialize walking a per-device list of all registered
214 * clients.)
215 *
216 * RCU is used to handle incoming connections racing with device teardown.
217 * Rather than use a lock to serialize removal from the client_data and
218 * getting a new reference, we use an RCU grace period.  The destruction
219 * path removes the device from client_data and then waits for all RCU
220 * readers to finish.
221 *
222 * A new connection can get NULL from this if its arriving on a
223 * device that is in the process of being removed.
224 */
225struct rds_ib_device *rds_ib_get_client_data(struct ib_device *device)
226{
227	struct rds_ib_device *rds_ibdev;
228
229	rcu_read_lock();
230	rds_ibdev = ib_get_client_data(device, &rds_ib_client);
231	if (rds_ibdev)
232		atomic_inc(&rds_ibdev->refcount);
233	rcu_read_unlock();
234	return rds_ibdev;
235}
236
237/*
238 * The IB stack is letting us know that a device is going away.  This can
239 * happen if the underlying HCA driver is removed or if PCI hotplug is removing
240 * the pci function, for example.
241 *
242 * This can be called at any time and can be racing with any other RDS path.
243 */
244static void rds_ib_remove_one(struct ib_device *device, void *client_data)
245{
246	struct rds_ib_device *rds_ibdev = client_data;
247
 
248	if (!rds_ibdev)
249		return;
250
251	rds_ib_dev_shutdown(rds_ibdev);
252
253	/* stop connection attempts from getting a reference to this device. */
254	ib_set_client_data(device, &rds_ib_client, NULL);
255
256	down_write(&rds_ib_devices_lock);
257	list_del_rcu(&rds_ibdev->list);
258	up_write(&rds_ib_devices_lock);
259
260	/*
261	 * This synchronize rcu is waiting for readers of both the ib
262	 * client data and the devices list to finish before we drop
263	 * both of those references.
264	 */
265	synchronize_rcu();
266	rds_ib_dev_put(rds_ibdev);
267	rds_ib_dev_put(rds_ibdev);
268}
269
270struct ib_client rds_ib_client = {
271	.name   = "rds_ib",
272	.add    = rds_ib_add_one,
273	.remove = rds_ib_remove_one
274};
275
276static int rds_ib_conn_info_visitor(struct rds_connection *conn,
277				    void *buffer)
278{
279	struct rds_info_rdma_connection *iinfo = buffer;
280	struct rds_ib_connection *ic;
281
282	/* We will only ever look at IB transports */
283	if (conn->c_trans != &rds_ib_transport)
284		return 0;
285
286	iinfo->src_addr = conn->c_laddr;
287	iinfo->dst_addr = conn->c_faddr;
288
289	memset(&iinfo->src_gid, 0, sizeof(iinfo->src_gid));
290	memset(&iinfo->dst_gid, 0, sizeof(iinfo->dst_gid));
291	if (rds_conn_state(conn) == RDS_CONN_UP) {
292		struct rds_ib_device *rds_ibdev;
293		struct rdma_dev_addr *dev_addr;
294
295		ic = conn->c_transport_data;
296		dev_addr = &ic->i_cm_id->route.addr.dev_addr;
297
298		rdma_addr_get_sgid(dev_addr, (union ib_gid *) &iinfo->src_gid);
299		rdma_addr_get_dgid(dev_addr, (union ib_gid *) &iinfo->dst_gid);
300
301		rds_ibdev = ic->rds_ibdev;
302		iinfo->max_send_wr = ic->i_send_ring.w_nr;
303		iinfo->max_recv_wr = ic->i_recv_ring.w_nr;
304		iinfo->max_send_sge = rds_ibdev->max_sge;
305		rds_ib_get_mr_info(rds_ibdev, iinfo);
306	}
307	return 1;
308}
309
310static void rds_ib_ic_info(struct socket *sock, unsigned int len,
311			   struct rds_info_iterator *iter,
312			   struct rds_info_lengths *lens)
313{
314	rds_for_each_conn_info(sock, len, iter, lens,
315				rds_ib_conn_info_visitor,
316				sizeof(struct rds_info_rdma_connection));
317}
318
319
320/*
321 * Early RDS/IB was built to only bind to an address if there is an IPoIB
322 * device with that address set.
323 *
324 * If it were me, I'd advocate for something more flexible.  Sending and
325 * receiving should be device-agnostic.  Transports would try and maintain
326 * connections between peers who have messages queued.  Userspace would be
327 * allowed to influence which paths have priority.  We could call userspace
328 * asserting this policy "routing".
329 */
330static int rds_ib_laddr_check(struct net *net, __be32 addr)
331{
332	int ret;
333	struct rdma_cm_id *cm_id;
334	struct sockaddr_in sin;
335
336	/* Create a CMA ID and try to bind it. This catches both
337	 * IB and iWARP capable NICs.
338	 */
339	cm_id = rdma_create_id(&init_net, NULL, NULL, RDMA_PS_TCP, IB_QPT_RC);
340	if (IS_ERR(cm_id))
341		return PTR_ERR(cm_id);
342
343	memset(&sin, 0, sizeof(sin));
344	sin.sin_family = AF_INET;
345	sin.sin_addr.s_addr = addr;
346
347	/* rdma_bind_addr will only succeed for IB & iWARP devices */
348	ret = rdma_bind_addr(cm_id, (struct sockaddr *)&sin);
349	/* due to this, we will claim to support iWARP devices unless we
350	   check node_type. */
351	if (ret || !cm_id->device ||
352	    cm_id->device->node_type != RDMA_NODE_IB_CA)
353		ret = -EADDRNOTAVAIL;
354
355	rdsdebug("addr %pI4 ret %d node type %d\n",
356		&addr, ret,
357		cm_id->device ? cm_id->device->node_type : -1);
358
359	rdma_destroy_id(cm_id);
360
361	return ret;
362}
363
364static void rds_ib_unregister_client(void)
365{
366	ib_unregister_client(&rds_ib_client);
367	/* wait for rds_ib_dev_free() to complete */
368	flush_workqueue(rds_wq);
369}
370
371void rds_ib_exit(void)
372{
373	rds_info_deregister_func(RDS_INFO_IB_CONNECTIONS, rds_ib_ic_info);
374	rds_ib_unregister_client();
375	rds_ib_destroy_nodev_conns();
376	rds_ib_sysctl_exit();
377	rds_ib_recv_exit();
378	rds_trans_unregister(&rds_ib_transport);
379	rds_ib_mr_exit();
380}
381
382struct rds_transport rds_ib_transport = {
383	.laddr_check		= rds_ib_laddr_check,
384	.xmit_path_complete	= rds_ib_xmit_path_complete,
385	.xmit			= rds_ib_xmit,
386	.xmit_rdma		= rds_ib_xmit_rdma,
387	.xmit_atomic		= rds_ib_xmit_atomic,
388	.recv_path		= rds_ib_recv_path,
389	.conn_alloc		= rds_ib_conn_alloc,
390	.conn_free		= rds_ib_conn_free,
391	.conn_path_connect	= rds_ib_conn_path_connect,
392	.conn_path_shutdown	= rds_ib_conn_path_shutdown,
393	.inc_copy_to_user	= rds_ib_inc_copy_to_user,
394	.inc_free		= rds_ib_inc_free,
395	.cm_initiate_connect	= rds_ib_cm_initiate_connect,
396	.cm_handle_connect	= rds_ib_cm_handle_connect,
397	.cm_connect_complete	= rds_ib_cm_connect_complete,
398	.stats_info_copy	= rds_ib_stats_info_copy,
399	.exit			= rds_ib_exit,
400	.get_mr			= rds_ib_get_mr,
401	.sync_mr		= rds_ib_sync_mr,
402	.free_mr		= rds_ib_free_mr,
403	.flush_mrs		= rds_ib_flush_mrs,
404	.t_owner		= THIS_MODULE,
405	.t_name			= "infiniband",
406	.t_type			= RDS_TRANS_IB
407};
408
409int rds_ib_init(void)
410{
411	int ret;
412
413	INIT_LIST_HEAD(&rds_ib_devices);
414
415	ret = rds_ib_mr_init();
416	if (ret)
417		goto out;
418
419	ret = ib_register_client(&rds_ib_client);
420	if (ret)
421		goto out_mr_exit;
422
423	ret = rds_ib_sysctl_init();
424	if (ret)
425		goto out_ibreg;
426
427	ret = rds_ib_recv_init();
428	if (ret)
429		goto out_sysctl;
430
431	ret = rds_trans_register(&rds_ib_transport);
432	if (ret)
433		goto out_recv;
434
435	rds_info_register_func(RDS_INFO_IB_CONNECTIONS, rds_ib_ic_info);
436
437	goto out;
438
439out_recv:
440	rds_ib_recv_exit();
441out_sysctl:
442	rds_ib_sysctl_exit();
443out_ibreg:
444	rds_ib_unregister_client();
445out_mr_exit:
446	rds_ib_mr_exit();
447out:
448	return ret;
449}
450
451MODULE_LICENSE("GPL");
452
v3.1
  1/*
  2 * Copyright (c) 2006 Oracle.  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/kernel.h>
 34#include <linux/in.h>
 35#include <linux/if.h>
 36#include <linux/netdevice.h>
 37#include <linux/inetdevice.h>
 38#include <linux/if_arp.h>
 39#include <linux/delay.h>
 40#include <linux/slab.h>
 
 41
 
 42#include "rds.h"
 43#include "ib.h"
 
 44
 45static unsigned int fmr_pool_size = RDS_FMR_POOL_SIZE;
 46unsigned int fmr_message_size = RDS_FMR_SIZE + 1; /* +1 allows for unaligned MRs */
 47unsigned int rds_ib_retry_count = RDS_IB_DEFAULT_RETRY_COUNT;
 48
 49module_param(fmr_pool_size, int, 0444);
 50MODULE_PARM_DESC(fmr_pool_size, " Max number of fmr per HCA");
 51module_param(fmr_message_size, int, 0444);
 52MODULE_PARM_DESC(fmr_message_size, " Max size of a RDMA transfer");
 53module_param(rds_ib_retry_count, int, 0444);
 54MODULE_PARM_DESC(rds_ib_retry_count, " Number of hw retries before reporting an error");
 55
 56/*
 57 * we have a clumsy combination of RCU and a rwsem protecting this list
 58 * because it is used both in the get_mr fast path and while blocking in
 59 * the FMR flushing path.
 60 */
 61DECLARE_RWSEM(rds_ib_devices_lock);
 62struct list_head rds_ib_devices;
 63
 64/* NOTE: if also grabbing ibdev lock, grab this first */
 65DEFINE_SPINLOCK(ib_nodev_conns_lock);
 66LIST_HEAD(ib_nodev_conns);
 67
 68static void rds_ib_nodev_connect(void)
 69{
 70	struct rds_ib_connection *ic;
 71
 72	spin_lock(&ib_nodev_conns_lock);
 73	list_for_each_entry(ic, &ib_nodev_conns, ib_node)
 74		rds_conn_connect_if_down(ic->conn);
 75	spin_unlock(&ib_nodev_conns_lock);
 76}
 77
 78static void rds_ib_dev_shutdown(struct rds_ib_device *rds_ibdev)
 79{
 80	struct rds_ib_connection *ic;
 81	unsigned long flags;
 82
 83	spin_lock_irqsave(&rds_ibdev->spinlock, flags);
 84	list_for_each_entry(ic, &rds_ibdev->conn_list, ib_node)
 85		rds_conn_drop(ic->conn);
 86	spin_unlock_irqrestore(&rds_ibdev->spinlock, flags);
 87}
 88
 89/*
 90 * rds_ib_destroy_mr_pool() blocks on a few things and mrs drop references
 91 * from interrupt context so we push freing off into a work struct in krdsd.
 92 */
 93static void rds_ib_dev_free(struct work_struct *work)
 94{
 95	struct rds_ib_ipaddr *i_ipaddr, *i_next;
 96	struct rds_ib_device *rds_ibdev = container_of(work,
 97					struct rds_ib_device, free_work);
 98
 99	if (rds_ibdev->mr_pool)
100		rds_ib_destroy_mr_pool(rds_ibdev->mr_pool);
101	if (rds_ibdev->mr)
102		ib_dereg_mr(rds_ibdev->mr);
103	if (rds_ibdev->pd)
104		ib_dealloc_pd(rds_ibdev->pd);
105
106	list_for_each_entry_safe(i_ipaddr, i_next, &rds_ibdev->ipaddr_list, list) {
107		list_del(&i_ipaddr->list);
108		kfree(i_ipaddr);
109	}
110
111	kfree(rds_ibdev);
112}
113
114void rds_ib_dev_put(struct rds_ib_device *rds_ibdev)
115{
116	BUG_ON(atomic_read(&rds_ibdev->refcount) <= 0);
117	if (atomic_dec_and_test(&rds_ibdev->refcount))
118		queue_work(rds_wq, &rds_ibdev->free_work);
119}
120
121static void rds_ib_add_one(struct ib_device *device)
122{
123	struct rds_ib_device *rds_ibdev;
124	struct ib_device_attr *dev_attr;
125
126	/* Only handle IB (no iWARP) devices */
127	if (device->node_type != RDMA_NODE_IB_CA)
128		return;
129
130	dev_attr = kmalloc(sizeof *dev_attr, GFP_KERNEL);
131	if (!dev_attr)
132		return;
133
134	if (ib_query_device(device, dev_attr)) {
135		rdsdebug("Query device failed for %s\n", device->name);
136		goto free_attr;
137	}
138
139	rds_ibdev = kzalloc_node(sizeof(struct rds_ib_device), GFP_KERNEL,
140				 ibdev_to_node(device));
141	if (!rds_ibdev)
142		goto free_attr;
143
144	spin_lock_init(&rds_ibdev->spinlock);
145	atomic_set(&rds_ibdev->refcount, 1);
146	INIT_WORK(&rds_ibdev->free_work, rds_ib_dev_free);
147
148	rds_ibdev->max_wrs = dev_attr->max_qp_wr;
149	rds_ibdev->max_sge = min(dev_attr->max_sge, RDS_IB_MAX_SGE);
150
151	rds_ibdev->fmr_max_remaps = dev_attr->max_map_per_fmr?: 32;
152	rds_ibdev->max_fmrs = dev_attr->max_fmr ?
153			min_t(unsigned int, dev_attr->max_fmr, fmr_pool_size) :
154			fmr_pool_size;
 
 
 
 
 
 
 
 
 
 
155
156	rds_ibdev->max_initiator_depth = dev_attr->max_qp_init_rd_atom;
157	rds_ibdev->max_responder_resources = dev_attr->max_qp_rd_atom;
158
159	rds_ibdev->dev = device;
160	rds_ibdev->pd = ib_alloc_pd(device);
161	if (IS_ERR(rds_ibdev->pd)) {
162		rds_ibdev->pd = NULL;
163		goto put_dev;
164	}
165
166	rds_ibdev->mr = ib_get_dma_mr(rds_ibdev->pd, IB_ACCESS_LOCAL_WRITE);
167	if (IS_ERR(rds_ibdev->mr)) {
168		rds_ibdev->mr = NULL;
 
169		goto put_dev;
170	}
171
172	rds_ibdev->mr_pool = rds_ib_create_mr_pool(rds_ibdev);
173	if (IS_ERR(rds_ibdev->mr_pool)) {
174		rds_ibdev->mr_pool = NULL;
 
175		goto put_dev;
176	}
177
 
 
 
 
 
 
 
 
 
178	INIT_LIST_HEAD(&rds_ibdev->ipaddr_list);
179	INIT_LIST_HEAD(&rds_ibdev->conn_list);
180
181	down_write(&rds_ib_devices_lock);
182	list_add_tail_rcu(&rds_ibdev->list, &rds_ib_devices);
183	up_write(&rds_ib_devices_lock);
184	atomic_inc(&rds_ibdev->refcount);
185
186	ib_set_client_data(device, &rds_ib_client, rds_ibdev);
187	atomic_inc(&rds_ibdev->refcount);
188
189	rds_ib_nodev_connect();
190
191put_dev:
192	rds_ib_dev_put(rds_ibdev);
193free_attr:
194	kfree(dev_attr);
195}
196
197/*
198 * New connections use this to find the device to associate with the
199 * connection.  It's not in the fast path so we're not concerned about the
200 * performance of the IB call.  (As of this writing, it uses an interrupt
201 * blocking spinlock to serialize walking a per-device list of all registered
202 * clients.)
203 *
204 * RCU is used to handle incoming connections racing with device teardown.
205 * Rather than use a lock to serialize removal from the client_data and
206 * getting a new reference, we use an RCU grace period.  The destruction
207 * path removes the device from client_data and then waits for all RCU
208 * readers to finish.
209 *
210 * A new connection can get NULL from this if its arriving on a
211 * device that is in the process of being removed.
212 */
213struct rds_ib_device *rds_ib_get_client_data(struct ib_device *device)
214{
215	struct rds_ib_device *rds_ibdev;
216
217	rcu_read_lock();
218	rds_ibdev = ib_get_client_data(device, &rds_ib_client);
219	if (rds_ibdev)
220		atomic_inc(&rds_ibdev->refcount);
221	rcu_read_unlock();
222	return rds_ibdev;
223}
224
225/*
226 * The IB stack is letting us know that a device is going away.  This can
227 * happen if the underlying HCA driver is removed or if PCI hotplug is removing
228 * the pci function, for example.
229 *
230 * This can be called at any time and can be racing with any other RDS path.
231 */
232static void rds_ib_remove_one(struct ib_device *device)
233{
234	struct rds_ib_device *rds_ibdev;
235
236	rds_ibdev = ib_get_client_data(device, &rds_ib_client);
237	if (!rds_ibdev)
238		return;
239
240	rds_ib_dev_shutdown(rds_ibdev);
241
242	/* stop connection attempts from getting a reference to this device. */
243	ib_set_client_data(device, &rds_ib_client, NULL);
244
245	down_write(&rds_ib_devices_lock);
246	list_del_rcu(&rds_ibdev->list);
247	up_write(&rds_ib_devices_lock);
248
249	/*
250	 * This synchronize rcu is waiting for readers of both the ib
251	 * client data and the devices list to finish before we drop
252	 * both of those references.
253	 */
254	synchronize_rcu();
255	rds_ib_dev_put(rds_ibdev);
256	rds_ib_dev_put(rds_ibdev);
257}
258
259struct ib_client rds_ib_client = {
260	.name   = "rds_ib",
261	.add    = rds_ib_add_one,
262	.remove = rds_ib_remove_one
263};
264
265static int rds_ib_conn_info_visitor(struct rds_connection *conn,
266				    void *buffer)
267{
268	struct rds_info_rdma_connection *iinfo = buffer;
269	struct rds_ib_connection *ic;
270
271	/* We will only ever look at IB transports */
272	if (conn->c_trans != &rds_ib_transport)
273		return 0;
274
275	iinfo->src_addr = conn->c_laddr;
276	iinfo->dst_addr = conn->c_faddr;
277
278	memset(&iinfo->src_gid, 0, sizeof(iinfo->src_gid));
279	memset(&iinfo->dst_gid, 0, sizeof(iinfo->dst_gid));
280	if (rds_conn_state(conn) == RDS_CONN_UP) {
281		struct rds_ib_device *rds_ibdev;
282		struct rdma_dev_addr *dev_addr;
283
284		ic = conn->c_transport_data;
285		dev_addr = &ic->i_cm_id->route.addr.dev_addr;
286
287		rdma_addr_get_sgid(dev_addr, (union ib_gid *) &iinfo->src_gid);
288		rdma_addr_get_dgid(dev_addr, (union ib_gid *) &iinfo->dst_gid);
289
290		rds_ibdev = ic->rds_ibdev;
291		iinfo->max_send_wr = ic->i_send_ring.w_nr;
292		iinfo->max_recv_wr = ic->i_recv_ring.w_nr;
293		iinfo->max_send_sge = rds_ibdev->max_sge;
294		rds_ib_get_mr_info(rds_ibdev, iinfo);
295	}
296	return 1;
297}
298
299static void rds_ib_ic_info(struct socket *sock, unsigned int len,
300			   struct rds_info_iterator *iter,
301			   struct rds_info_lengths *lens)
302{
303	rds_for_each_conn_info(sock, len, iter, lens,
304				rds_ib_conn_info_visitor,
305				sizeof(struct rds_info_rdma_connection));
306}
307
308
309/*
310 * Early RDS/IB was built to only bind to an address if there is an IPoIB
311 * device with that address set.
312 *
313 * If it were me, I'd advocate for something more flexible.  Sending and
314 * receiving should be device-agnostic.  Transports would try and maintain
315 * connections between peers who have messages queued.  Userspace would be
316 * allowed to influence which paths have priority.  We could call userspace
317 * asserting this policy "routing".
318 */
319static int rds_ib_laddr_check(__be32 addr)
320{
321	int ret;
322	struct rdma_cm_id *cm_id;
323	struct sockaddr_in sin;
324
325	/* Create a CMA ID and try to bind it. This catches both
326	 * IB and iWARP capable NICs.
327	 */
328	cm_id = rdma_create_id(NULL, NULL, RDMA_PS_TCP, IB_QPT_RC);
329	if (IS_ERR(cm_id))
330		return PTR_ERR(cm_id);
331
332	memset(&sin, 0, sizeof(sin));
333	sin.sin_family = AF_INET;
334	sin.sin_addr.s_addr = addr;
335
336	/* rdma_bind_addr will only succeed for IB & iWARP devices */
337	ret = rdma_bind_addr(cm_id, (struct sockaddr *)&sin);
338	/* due to this, we will claim to support iWARP devices unless we
339	   check node_type. */
340	if (ret || cm_id->device->node_type != RDMA_NODE_IB_CA)
 
341		ret = -EADDRNOTAVAIL;
342
343	rdsdebug("addr %pI4 ret %d node type %d\n",
344		&addr, ret,
345		cm_id->device ? cm_id->device->node_type : -1);
346
347	rdma_destroy_id(cm_id);
348
349	return ret;
350}
351
352static void rds_ib_unregister_client(void)
353{
354	ib_unregister_client(&rds_ib_client);
355	/* wait for rds_ib_dev_free() to complete */
356	flush_workqueue(rds_wq);
357}
358
359void rds_ib_exit(void)
360{
361	rds_info_deregister_func(RDS_INFO_IB_CONNECTIONS, rds_ib_ic_info);
362	rds_ib_unregister_client();
363	rds_ib_destroy_nodev_conns();
364	rds_ib_sysctl_exit();
365	rds_ib_recv_exit();
366	rds_trans_unregister(&rds_ib_transport);
 
367}
368
369struct rds_transport rds_ib_transport = {
370	.laddr_check		= rds_ib_laddr_check,
371	.xmit_complete		= rds_ib_xmit_complete,
372	.xmit			= rds_ib_xmit,
373	.xmit_rdma		= rds_ib_xmit_rdma,
374	.xmit_atomic		= rds_ib_xmit_atomic,
375	.recv			= rds_ib_recv,
376	.conn_alloc		= rds_ib_conn_alloc,
377	.conn_free		= rds_ib_conn_free,
378	.conn_connect		= rds_ib_conn_connect,
379	.conn_shutdown		= rds_ib_conn_shutdown,
380	.inc_copy_to_user	= rds_ib_inc_copy_to_user,
381	.inc_free		= rds_ib_inc_free,
382	.cm_initiate_connect	= rds_ib_cm_initiate_connect,
383	.cm_handle_connect	= rds_ib_cm_handle_connect,
384	.cm_connect_complete	= rds_ib_cm_connect_complete,
385	.stats_info_copy	= rds_ib_stats_info_copy,
386	.exit			= rds_ib_exit,
387	.get_mr			= rds_ib_get_mr,
388	.sync_mr		= rds_ib_sync_mr,
389	.free_mr		= rds_ib_free_mr,
390	.flush_mrs		= rds_ib_flush_mrs,
391	.t_owner		= THIS_MODULE,
392	.t_name			= "infiniband",
393	.t_type			= RDS_TRANS_IB
394};
395
396int rds_ib_init(void)
397{
398	int ret;
399
400	INIT_LIST_HEAD(&rds_ib_devices);
401
 
 
 
 
402	ret = ib_register_client(&rds_ib_client);
403	if (ret)
404		goto out;
405
406	ret = rds_ib_sysctl_init();
407	if (ret)
408		goto out_ibreg;
409
410	ret = rds_ib_recv_init();
411	if (ret)
412		goto out_sysctl;
413
414	ret = rds_trans_register(&rds_ib_transport);
415	if (ret)
416		goto out_recv;
417
418	rds_info_register_func(RDS_INFO_IB_CONNECTIONS, rds_ib_ic_info);
419
420	goto out;
421
422out_recv:
423	rds_ib_recv_exit();
424out_sysctl:
425	rds_ib_sysctl_exit();
426out_ibreg:
427	rds_ib_unregister_client();
 
 
428out:
429	return ret;
430}
431
432MODULE_LICENSE("GPL");
433