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