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