rds: make local functions/variables static
[linux-3.10.git] / net / rds / ib.c
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
45 static unsigned int fmr_pool_size = RDS_FMR_POOL_SIZE;
46 unsigned int fmr_message_size = RDS_FMR_SIZE + 1; /* +1 allows for unaligned MRs */
47 unsigned int rds_ib_retry_count = RDS_IB_DEFAULT_RETRY_COUNT;
48
49 module_param(fmr_pool_size, int, 0444);
50 MODULE_PARM_DESC(fmr_pool_size, " Max number of fmr per HCA");
51 module_param(fmr_message_size, int, 0444);
52 MODULE_PARM_DESC(fmr_message_size, " Max size of a RDMA transfer");
53 module_param(rds_ib_retry_count, int, 0444);
54 MODULE_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  */
61 DECLARE_RWSEM(rds_ib_devices_lock);
62 struct list_head rds_ib_devices;
63
64 /* NOTE: if also grabbing ibdev lock, grab this first */
65 DEFINE_SPINLOCK(ib_nodev_conns_lock);
66 LIST_HEAD(ib_nodev_conns);
67
68 static 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
78 static 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  */
93 static 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
114 void 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
121 static 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
191 put_dev:
192         rds_ib_dev_put(rds_ibdev);
193 free_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  */
213 struct 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  */
232 static 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
259 struct ib_client rds_ib_client = {
260         .name   = "rds_ib",
261         .add    = rds_ib_add_one,
262         .remove = rds_ib_remove_one
263 };
264
265 static 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
299 static 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  */
319 static 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);
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
352 static 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
359 void 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         rds_ib_fmr_exit();
368 }
369
370 struct 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
397 int rds_ib_init(void)
398 {
399         int ret;
400
401         INIT_LIST_HEAD(&rds_ib_devices);
402
403         ret = rds_ib_fmr_init();
404         if (ret)
405                 goto out;
406
407         ret = ib_register_client(&rds_ib_client);
408         if (ret)
409                 goto out_fmr_exit;
410
411         ret = rds_ib_sysctl_init();
412         if (ret)
413                 goto out_ibreg;
414
415         ret = rds_ib_recv_init();
416         if (ret)
417                 goto out_sysctl;
418
419         ret = rds_trans_register(&rds_ib_transport);
420         if (ret)
421                 goto out_recv;
422
423         rds_info_register_func(RDS_INFO_IB_CONNECTIONS, rds_ib_ic_info);
424
425         goto out;
426
427 out_recv:
428         rds_ib_recv_exit();
429 out_sysctl:
430         rds_ib_sysctl_exit();
431 out_ibreg:
432         rds_ib_unregister_client();
433 out_fmr_exit:
434         rds_ib_fmr_exit();
435 out:
436         return ret;
437 }
438
439 MODULE_LICENSE("GPL");
440