1// SPDX-License-Identifier: GPL-2.0
2/*
3 *  Shared Memory Communications over RDMA (SMC-R) and RoCE
4 *
5 *  IB infrastructure:
6 *  Establish SMC-R as an Infiniband Client to be notified about added and
7 *  removed IB devices of type RDMA.
8 *  Determine device and port characteristics for these IB devices.
9 *
10 *  Copyright IBM Corp. 2016
11 *
12 *  Author(s):  Ursula Braun <ubraun@linux.vnet.ibm.com>
13 */
14
15#include <linux/etherdevice.h>
16#include <linux/if_vlan.h>
17#include <linux/random.h>
18#include <linux/workqueue.h>
19#include <linux/scatterlist.h>
20#include <linux/wait.h>
21#include <linux/mutex.h>
22#include <linux/inetdevice.h>
23#include <rdma/ib_verbs.h>
24#include <rdma/ib_cache.h>
25
26#include "smc_pnet.h"
27#include "smc_ib.h"
28#include "smc_core.h"
29#include "smc_wr.h"
30#include "smc.h"
31#include "smc_netlink.h"
32
33#define SMC_MAX_CQE 32766	/* max. # of completion queue elements */
34
35#define SMC_QP_MIN_RNR_TIMER		5
36#define SMC_QP_TIMEOUT			15 /* 4096 * 2 ** timeout usec */
37#define SMC_QP_RETRY_CNT			7 /* 7: infinite */
38#define SMC_QP_RNR_RETRY			7 /* 7: infinite */
39
40struct smc_ib_devices smc_ib_devices = {	/* smc-registered ib devices */
41	.mutex = __MUTEX_INITIALIZER(smc_ib_devices.mutex),
42	.list = LIST_HEAD_INIT(smc_ib_devices.list),
43};
44
45u8 local_systemid[SMC_SYSTEMID_LEN];		/* unique system identifier */
46
47static int smc_ib_modify_qp_init(struct smc_link *lnk)
48{
49	struct ib_qp_attr qp_attr;
50
51	memset(&qp_attr, 0, sizeof(qp_attr));
52	qp_attr.qp_state = IB_QPS_INIT;
53	qp_attr.pkey_index = 0;
54	qp_attr.port_num = lnk->ibport;
55	qp_attr.qp_access_flags = IB_ACCESS_LOCAL_WRITE
56				| IB_ACCESS_REMOTE_WRITE;
57	return ib_modify_qp(lnk->roce_qp, &qp_attr,
58			    IB_QP_STATE | IB_QP_PKEY_INDEX |
59			    IB_QP_ACCESS_FLAGS | IB_QP_PORT);
60}
61
62static int smc_ib_modify_qp_rtr(struct smc_link *lnk)
63{
64	enum ib_qp_attr_mask qp_attr_mask =
65		IB_QP_STATE | IB_QP_AV | IB_QP_PATH_MTU | IB_QP_DEST_QPN |
66		IB_QP_RQ_PSN | IB_QP_MAX_DEST_RD_ATOMIC | IB_QP_MIN_RNR_TIMER;
67	struct ib_qp_attr qp_attr;
68	u8 hop_lim = 1;
69
70	memset(&qp_attr, 0, sizeof(qp_attr));
71	qp_attr.qp_state = IB_QPS_RTR;
72	qp_attr.path_mtu = min(lnk->path_mtu, lnk->peer_mtu);
73	qp_attr.ah_attr.type = RDMA_AH_ATTR_TYPE_ROCE;
74	rdma_ah_set_port_num(&qp_attr.ah_attr, lnk->ibport);
75	if (lnk->lgr->smc_version == SMC_V2 && lnk->lgr->uses_gateway)
76		hop_lim = IPV6_DEFAULT_HOPLIMIT;
77	rdma_ah_set_grh(&qp_attr.ah_attr, NULL, 0, lnk->sgid_index, hop_lim, 0);
78	rdma_ah_set_dgid_raw(&qp_attr.ah_attr, lnk->peer_gid);
79	if (lnk->lgr->smc_version == SMC_V2 && lnk->lgr->uses_gateway)
80		memcpy(&qp_attr.ah_attr.roce.dmac, lnk->lgr->nexthop_mac,
81		       sizeof(lnk->lgr->nexthop_mac));
82	else
83		memcpy(&qp_attr.ah_attr.roce.dmac, lnk->peer_mac,
84		       sizeof(lnk->peer_mac));
85	qp_attr.dest_qp_num = lnk->peer_qpn;
86	qp_attr.rq_psn = lnk->peer_psn; /* starting receive packet seq # */
87	qp_attr.max_dest_rd_atomic = 1; /* max # of resources for incoming
88					 * requests
89					 */
90	qp_attr.min_rnr_timer = SMC_QP_MIN_RNR_TIMER;
91
92	return ib_modify_qp(lnk->roce_qp, &qp_attr, qp_attr_mask);
93}
94
95int smc_ib_modify_qp_rts(struct smc_link *lnk)
96{
97	struct ib_qp_attr qp_attr;
98
99	memset(&qp_attr, 0, sizeof(qp_attr));
100	qp_attr.qp_state = IB_QPS_RTS;
101	qp_attr.timeout = SMC_QP_TIMEOUT;	/* local ack timeout */
102	qp_attr.retry_cnt = SMC_QP_RETRY_CNT;	/* retry count */
103	qp_attr.rnr_retry = SMC_QP_RNR_RETRY;	/* RNR retries, 7=infinite */
104	qp_attr.sq_psn = lnk->psn_initial;	/* starting send packet seq # */
105	qp_attr.max_rd_atomic = 1;	/* # of outstanding RDMA reads and
106					 * atomic ops allowed
107					 */
108	return ib_modify_qp(lnk->roce_qp, &qp_attr,
109			    IB_QP_STATE | IB_QP_TIMEOUT | IB_QP_RETRY_CNT |
110			    IB_QP_SQ_PSN | IB_QP_RNR_RETRY |
111			    IB_QP_MAX_QP_RD_ATOMIC);
112}
113
114int smc_ib_modify_qp_error(struct smc_link *lnk)
115{
116	struct ib_qp_attr qp_attr;
117
118	memset(&qp_attr, 0, sizeof(qp_attr));
119	qp_attr.qp_state = IB_QPS_ERR;
120	return ib_modify_qp(lnk->roce_qp, &qp_attr, IB_QP_STATE);
121}
122
123int smc_ib_ready_link(struct smc_link *lnk)
124{
125	struct smc_link_group *lgr = smc_get_lgr(lnk);
126	int rc = 0;
127
128	rc = smc_ib_modify_qp_init(lnk);
129	if (rc)
130		goto out;
131
132	rc = smc_ib_modify_qp_rtr(lnk);
133	if (rc)
134		goto out;
135	smc_wr_remember_qp_attr(lnk);
136	rc = ib_req_notify_cq(lnk->smcibdev->roce_cq_recv,
137			      IB_CQ_SOLICITED_MASK);
138	if (rc)
139		goto out;
140	rc = smc_wr_rx_post_init(lnk);
141	if (rc)
142		goto out;
143	smc_wr_remember_qp_attr(lnk);
144
145	if (lgr->role == SMC_SERV) {
146		rc = smc_ib_modify_qp_rts(lnk);
147		if (rc)
148			goto out;
149		smc_wr_remember_qp_attr(lnk);
150	}
151out:
152	return rc;
153}
154
155static int smc_ib_fill_mac(struct smc_ib_device *smcibdev, u8 ibport)
156{
157	const struct ib_gid_attr *attr;
158	int rc;
159
160	attr = rdma_get_gid_attr(smcibdev->ibdev, ibport, 0);
161	if (IS_ERR(attr))
162		return -ENODEV;
163
164	rc = rdma_read_gid_l2_fields(attr, NULL, smcibdev->mac[ibport - 1]);
165	rdma_put_gid_attr(attr);
166	return rc;
167}
168
169/* Create an identifier unique for this instance of SMC-R.
170 * The MAC-address of the first active registered IB device
171 * plus a random 2-byte number is used to create this identifier.
172 * This name is delivered to the peer during connection initialization.
173 */
174static inline void smc_ib_define_local_systemid(struct smc_ib_device *smcibdev,
175						u8 ibport)
176{
177	memcpy(&local_systemid[2], &smcibdev->mac[ibport - 1],
178	       sizeof(smcibdev->mac[ibport - 1]));
179}
180
181bool smc_ib_is_valid_local_systemid(void)
182{
183	return !is_zero_ether_addr(&local_systemid[2]);
184}
185
186static void smc_ib_init_local_systemid(void)
187{
188	get_random_bytes(&local_systemid[0], 2);
189}
190
191bool smc_ib_port_active(struct smc_ib_device *smcibdev, u8 ibport)
192{
193	return smcibdev->pattr[ibport - 1].state == IB_PORT_ACTIVE;
194}
195
196int smc_ib_find_route(struct net *net, __be32 saddr, __be32 daddr,
197		      u8 nexthop_mac[], u8 *uses_gateway)
198{
199	struct neighbour *neigh = NULL;
200	struct rtable *rt = NULL;
201	struct flowi4 fl4 = {
202		.saddr = saddr,
203		.daddr = daddr
204	};
205
206	if (daddr == cpu_to_be32(INADDR_NONE))
207		goto out;
208	rt = ip_route_output_flow(net, &fl4, NULL);
209	if (IS_ERR(rt))
210		goto out;
211	if (rt->rt_uses_gateway && rt->rt_gw_family != AF_INET)
212		goto out;
213	neigh = rt->dst.ops->neigh_lookup(&rt->dst, NULL, &fl4.daddr);
214	if (neigh) {
215		memcpy(nexthop_mac, neigh->ha, ETH_ALEN);
216		*uses_gateway = rt->rt_uses_gateway;
217		return 0;
218	}
219out:
220	return -ENOENT;
221}
222
223static int smc_ib_determine_gid_rcu(const struct net_device *ndev,
224				    const struct ib_gid_attr *attr,
225				    u8 gid[], u8 *sgid_index,
226				    struct smc_init_info_smcrv2 *smcrv2)
227{
228	if (!smcrv2 && attr->gid_type == IB_GID_TYPE_ROCE) {
229		if (gid)
230			memcpy(gid, &attr->gid, SMC_GID_SIZE);
231		if (sgid_index)
232			*sgid_index = attr->index;
233		return 0;
234	}
235	if (smcrv2 && attr->gid_type == IB_GID_TYPE_ROCE_UDP_ENCAP &&
236	    smc_ib_gid_to_ipv4((u8 *)&attr->gid) != cpu_to_be32(INADDR_NONE)) {
237		struct in_device *in_dev = __in_dev_get_rcu(ndev);
238		struct net *net = dev_net(ndev);
239		const struct in_ifaddr *ifa;
240		bool subnet_match = false;
241
242		if (!in_dev)
243			goto out;
244		in_dev_for_each_ifa_rcu(ifa, in_dev) {
245			if (!inet_ifa_match(smcrv2->saddr, ifa))
246				continue;
247			subnet_match = true;
248			break;
249		}
250		if (!subnet_match)
251			goto out;
252		if (smcrv2->daddr && smc_ib_find_route(net, smcrv2->saddr,
253						       smcrv2->daddr,
254						       smcrv2->nexthop_mac,
255						       &smcrv2->uses_gateway))
256			goto out;
257
258		if (gid)
259			memcpy(gid, &attr->gid, SMC_GID_SIZE);
260		if (sgid_index)
261			*sgid_index = attr->index;
262		return 0;
263	}
264out:
265	return -ENODEV;
266}
267
268/* determine the gid for an ib-device port and vlan id */
269int smc_ib_determine_gid(struct smc_ib_device *smcibdev, u8 ibport,
270			 unsigned short vlan_id, u8 gid[], u8 *sgid_index,
271			 struct smc_init_info_smcrv2 *smcrv2)
272{
273	const struct ib_gid_attr *attr;
274	const struct net_device *ndev;
275	int i;
276
277	for (i = 0; i < smcibdev->pattr[ibport - 1].gid_tbl_len; i++) {
278		attr = rdma_get_gid_attr(smcibdev->ibdev, ibport, i);
279		if (IS_ERR(attr))
280			continue;
281
282		rcu_read_lock();
283		ndev = rdma_read_gid_attr_ndev_rcu(attr);
284		if (!IS_ERR(ndev) &&
285		    ((!vlan_id && !is_vlan_dev(ndev)) ||
286		     (vlan_id && is_vlan_dev(ndev) &&
287		      vlan_dev_vlan_id(ndev) == vlan_id))) {
288			if (!smc_ib_determine_gid_rcu(ndev, attr, gid,
289						      sgid_index, smcrv2)) {
290				rcu_read_unlock();
291				rdma_put_gid_attr(attr);
292				return 0;
293			}
294		}
295		rcu_read_unlock();
296		rdma_put_gid_attr(attr);
297	}
298	return -ENODEV;
299}
300
301/* check if gid is still defined on smcibdev */
302static bool smc_ib_check_link_gid(u8 gid[SMC_GID_SIZE], bool smcrv2,
303				  struct smc_ib_device *smcibdev, u8 ibport)
304{
305	const struct ib_gid_attr *attr;
306	bool rc = false;
307	int i;
308
309	for (i = 0; !rc && i < smcibdev->pattr[ibport - 1].gid_tbl_len; i++) {
310		attr = rdma_get_gid_attr(smcibdev->ibdev, ibport, i);
311		if (IS_ERR(attr))
312			continue;
313
314		rcu_read_lock();
315		if ((!smcrv2 && attr->gid_type == IB_GID_TYPE_ROCE) ||
316		    (smcrv2 && attr->gid_type == IB_GID_TYPE_ROCE_UDP_ENCAP &&
317		     !(ipv6_addr_type((const struct in6_addr *)&attr->gid)
318				     & IPV6_ADDR_LINKLOCAL)))
319			if (!memcmp(gid, &attr->gid, SMC_GID_SIZE))
320				rc = true;
321		rcu_read_unlock();
322		rdma_put_gid_attr(attr);
323	}
324	return rc;
325}
326
327/* check all links if the gid is still defined on smcibdev */
328static void smc_ib_gid_check(struct smc_ib_device *smcibdev, u8 ibport)
329{
330	struct smc_link_group *lgr;
331	int i;
332
333	spin_lock_bh(&smc_lgr_list.lock);
334	list_for_each_entry(lgr, &smc_lgr_list.list, list) {
335		if (strncmp(smcibdev->pnetid[ibport - 1], lgr->pnet_id,
336			    SMC_MAX_PNETID_LEN))
337			continue; /* lgr is not affected */
338		if (list_empty(&lgr->list))
339			continue;
340		for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
341			if (lgr->lnk[i].state == SMC_LNK_UNUSED ||
342			    lgr->lnk[i].smcibdev != smcibdev)
343				continue;
344			if (!smc_ib_check_link_gid(lgr->lnk[i].gid,
345						   lgr->smc_version == SMC_V2,
346						   smcibdev, ibport))
347				smcr_port_err(smcibdev, ibport);
348		}
349	}
350	spin_unlock_bh(&smc_lgr_list.lock);
351}
352
353static int smc_ib_remember_port_attr(struct smc_ib_device *smcibdev, u8 ibport)
354{
355	int rc;
356
357	memset(&smcibdev->pattr[ibport - 1], 0,
358	       sizeof(smcibdev->pattr[ibport - 1]));
359	rc = ib_query_port(smcibdev->ibdev, ibport,
360			   &smcibdev->pattr[ibport - 1]);
361	if (rc)
362		goto out;
363	/* the SMC protocol requires specification of the RoCE MAC address */
364	rc = smc_ib_fill_mac(smcibdev, ibport);
365	if (rc)
366		goto out;
367	if (!smc_ib_is_valid_local_systemid() &&
368	    smc_ib_port_active(smcibdev, ibport))
369		/* create unique system identifier */
370		smc_ib_define_local_systemid(smcibdev, ibport);
371out:
372	return rc;
373}
374
375/* process context wrapper for might_sleep smc_ib_remember_port_attr */
376static void smc_ib_port_event_work(struct work_struct *work)
377{
378	struct smc_ib_device *smcibdev = container_of(
379		work, struct smc_ib_device, port_event_work);
380	u8 port_idx;
381
382	for_each_set_bit(port_idx, &smcibdev->port_event_mask, SMC_MAX_PORTS) {
383		smc_ib_remember_port_attr(smcibdev, port_idx + 1);
384		clear_bit(port_idx, &smcibdev->port_event_mask);
385		if (!smc_ib_port_active(smcibdev, port_idx + 1)) {
386			set_bit(port_idx, smcibdev->ports_going_away);
387			smcr_port_err(smcibdev, port_idx + 1);
388		} else {
389			clear_bit(port_idx, smcibdev->ports_going_away);
390			smcr_port_add(smcibdev, port_idx + 1);
391			smc_ib_gid_check(smcibdev, port_idx + 1);
392		}
393	}
394}
395
396/* can be called in IRQ context */
397static void smc_ib_global_event_handler(struct ib_event_handler *handler,
398					struct ib_event *ibevent)
399{
400	struct smc_ib_device *smcibdev;
401	bool schedule = false;
402	u8 port_idx;
403
404	smcibdev = container_of(handler, struct smc_ib_device, event_handler);
405
406	switch (ibevent->event) {
407	case IB_EVENT_DEVICE_FATAL:
408		/* terminate all ports on device */
409		for (port_idx = 0; port_idx < SMC_MAX_PORTS; port_idx++) {
410			set_bit(port_idx, &smcibdev->port_event_mask);
411			if (!test_and_set_bit(port_idx,
412					      smcibdev->ports_going_away))
413				schedule = true;
414		}
415		if (schedule)
416			schedule_work(&smcibdev->port_event_work);
417		break;
418	case IB_EVENT_PORT_ACTIVE:
419		port_idx = ibevent->element.port_num - 1;
420		if (port_idx >= SMC_MAX_PORTS)
421			break;
422		set_bit(port_idx, &smcibdev->port_event_mask);
423		if (test_and_clear_bit(port_idx, smcibdev->ports_going_away))
424			schedule_work(&smcibdev->port_event_work);
425		break;
426	case IB_EVENT_PORT_ERR:
427		port_idx = ibevent->element.port_num - 1;
428		if (port_idx >= SMC_MAX_PORTS)
429			break;
430		set_bit(port_idx, &smcibdev->port_event_mask);
431		if (!test_and_set_bit(port_idx, smcibdev->ports_going_away))
432			schedule_work(&smcibdev->port_event_work);
433		break;
434	case IB_EVENT_GID_CHANGE:
435		port_idx = ibevent->element.port_num - 1;
436		if (port_idx >= SMC_MAX_PORTS)
437			break;
438		set_bit(port_idx, &smcibdev->port_event_mask);
439		schedule_work(&smcibdev->port_event_work);
440		break;
441	default:
442		break;
443	}
444}
445
446void smc_ib_dealloc_protection_domain(struct smc_link *lnk)
447{
448	if (lnk->roce_pd)
449		ib_dealloc_pd(lnk->roce_pd);
450	lnk->roce_pd = NULL;
451}
452
453int smc_ib_create_protection_domain(struct smc_link *lnk)
454{
455	int rc;
456
457	lnk->roce_pd = ib_alloc_pd(lnk->smcibdev->ibdev, 0);
458	rc = PTR_ERR_OR_ZERO(lnk->roce_pd);
459	if (IS_ERR(lnk->roce_pd))
460		lnk->roce_pd = NULL;
461	return rc;
462}
463
464static bool smcr_diag_is_dev_critical(struct smc_lgr_list *smc_lgr,
465				      struct smc_ib_device *smcibdev)
466{
467	struct smc_link_group *lgr;
468	bool rc = false;
469	int i;
470
471	spin_lock_bh(&smc_lgr->lock);
472	list_for_each_entry(lgr, &smc_lgr->list, list) {
473		if (lgr->is_smcd)
474			continue;
475		for (i = 0; i < SMC_LINKS_PER_LGR_MAX; i++) {
476			if (lgr->lnk[i].state == SMC_LNK_UNUSED ||
477			    lgr->lnk[i].smcibdev != smcibdev)
478				continue;
479			if (lgr->type == SMC_LGR_SINGLE ||
480			    lgr->type == SMC_LGR_ASYMMETRIC_LOCAL) {
481				rc = true;
482				goto out;
483			}
484		}
485	}
486out:
487	spin_unlock_bh(&smc_lgr->lock);
488	return rc;
489}
490
491static int smc_nl_handle_dev_port(struct sk_buff *skb,
492				  struct ib_device *ibdev,
493				  struct smc_ib_device *smcibdev,
494				  int port)
495{
496	char smc_pnet[SMC_MAX_PNETID_LEN + 1];
497	struct nlattr *port_attrs;
498	unsigned char port_state;
499	int lnk_count = 0;
500
501	port_attrs = nla_nest_start(skb, SMC_NLA_DEV_PORT + port);
502	if (!port_attrs)
503		goto errout;
504
505	if (nla_put_u8(skb, SMC_NLA_DEV_PORT_PNET_USR,
506		       smcibdev->pnetid_by_user[port]))
507		goto errattr;
508	memcpy(smc_pnet, &smcibdev->pnetid[port], SMC_MAX_PNETID_LEN);
509	smc_pnet[SMC_MAX_PNETID_LEN] = 0;
510	if (nla_put_string(skb, SMC_NLA_DEV_PORT_PNETID, smc_pnet))
511		goto errattr;
512	if (nla_put_u32(skb, SMC_NLA_DEV_PORT_NETDEV,
513			smcibdev->ndev_ifidx[port]))
514		goto errattr;
515	if (nla_put_u8(skb, SMC_NLA_DEV_PORT_VALID, 1))
516		goto errattr;
517	port_state = smc_ib_port_active(smcibdev, port + 1);
518	if (nla_put_u8(skb, SMC_NLA_DEV_PORT_STATE, port_state))
519		goto errattr;
520	lnk_count = atomic_read(&smcibdev->lnk_cnt_by_port[port]);
521	if (nla_put_u32(skb, SMC_NLA_DEV_PORT_LNK_CNT, lnk_count))
522		goto errattr;
523	nla_nest_end(skb, port_attrs);
524	return 0;
525errattr:
526	nla_nest_cancel(skb, port_attrs);
527errout:
528	return -EMSGSIZE;
529}
530
531static bool smc_nl_handle_pci_values(const struct smc_pci_dev *smc_pci_dev,
532				     struct sk_buff *skb)
533{
534	if (nla_put_u32(skb, SMC_NLA_DEV_PCI_FID, smc_pci_dev->pci_fid))
535		return false;
536	if (nla_put_u16(skb, SMC_NLA_DEV_PCI_CHID, smc_pci_dev->pci_pchid))
537		return false;
538	if (nla_put_u16(skb, SMC_NLA_DEV_PCI_VENDOR, smc_pci_dev->pci_vendor))
539		return false;
540	if (nla_put_u16(skb, SMC_NLA_DEV_PCI_DEVICE, smc_pci_dev->pci_device))
541		return false;
542	if (nla_put_string(skb, SMC_NLA_DEV_PCI_ID, smc_pci_dev->pci_id))
543		return false;
544	return true;
545}
546
547static int smc_nl_handle_smcr_dev(struct smc_ib_device *smcibdev,
548				  struct sk_buff *skb,
549				  struct netlink_callback *cb)
550{
551	char smc_ibname[IB_DEVICE_NAME_MAX];
552	struct smc_pci_dev smc_pci_dev;
553	struct pci_dev *pci_dev;
554	unsigned char is_crit;
555	struct nlattr *attrs;
556	void *nlh;
557	int i;
558
559	nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
560			  &smc_gen_nl_family, NLM_F_MULTI,
561			  SMC_NETLINK_GET_DEV_SMCR);
562	if (!nlh)
563		goto errmsg;
564	attrs = nla_nest_start(skb, SMC_GEN_DEV_SMCR);
565	if (!attrs)
566		goto errout;
567	is_crit = smcr_diag_is_dev_critical(&smc_lgr_list, smcibdev);
568	if (nla_put_u8(skb, SMC_NLA_DEV_IS_CRIT, is_crit))
569		goto errattr;
570	if (smcibdev->ibdev->dev.parent) {
571		memset(&smc_pci_dev, 0, sizeof(smc_pci_dev));
572		pci_dev = to_pci_dev(smcibdev->ibdev->dev.parent);
573		smc_set_pci_values(pci_dev, &smc_pci_dev);
574		if (!smc_nl_handle_pci_values(&smc_pci_dev, skb))
575			goto errattr;
576	}
577	snprintf(smc_ibname, sizeof(smc_ibname), "%s", smcibdev->ibdev->name);
578	if (nla_put_string(skb, SMC_NLA_DEV_IB_NAME, smc_ibname))
579		goto errattr;
580	for (i = 1; i <= SMC_MAX_PORTS; i++) {
581		if (!rdma_is_port_valid(smcibdev->ibdev, i))
582			continue;
583		if (smc_nl_handle_dev_port(skb, smcibdev->ibdev,
584					   smcibdev, i - 1))
585			goto errattr;
586	}
587
588	nla_nest_end(skb, attrs);
589	genlmsg_end(skb, nlh);
590	return 0;
591
592errattr:
593	nla_nest_cancel(skb, attrs);
594errout:
595	genlmsg_cancel(skb, nlh);
596errmsg:
597	return -EMSGSIZE;
598}
599
600static void smc_nl_prep_smcr_dev(struct smc_ib_devices *dev_list,
601				 struct sk_buff *skb,
602				 struct netlink_callback *cb)
603{
604	struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
605	struct smc_ib_device *smcibdev;
606	int snum = cb_ctx->pos[0];
607	int num = 0;
608
609	mutex_lock(&dev_list->mutex);
610	list_for_each_entry(smcibdev, &dev_list->list, list) {
611		if (num < snum)
612			goto next;
613		if (smc_nl_handle_smcr_dev(smcibdev, skb, cb))
614			goto errout;
615next:
616		num++;
617	}
618errout:
619	mutex_unlock(&dev_list->mutex);
620	cb_ctx->pos[0] = num;
621}
622
623int smcr_nl_get_device(struct sk_buff *skb, struct netlink_callback *cb)
624{
625	smc_nl_prep_smcr_dev(&smc_ib_devices, skb, cb);
626	return skb->len;
627}
628
629static void smc_ib_qp_event_handler(struct ib_event *ibevent, void *priv)
630{
631	struct smc_link *lnk = (struct smc_link *)priv;
632	struct smc_ib_device *smcibdev = lnk->smcibdev;
633	u8 port_idx;
634
635	switch (ibevent->event) {
636	case IB_EVENT_QP_FATAL:
637	case IB_EVENT_QP_ACCESS_ERR:
638		port_idx = ibevent->element.qp->port - 1;
639		if (port_idx >= SMC_MAX_PORTS)
640			break;
641		set_bit(port_idx, &smcibdev->port_event_mask);
642		if (!test_and_set_bit(port_idx, smcibdev->ports_going_away))
643			schedule_work(&smcibdev->port_event_work);
644		break;
645	default:
646		break;
647	}
648}
649
650void smc_ib_destroy_queue_pair(struct smc_link *lnk)
651{
652	if (lnk->roce_qp)
653		ib_destroy_qp(lnk->roce_qp);
654	lnk->roce_qp = NULL;
655}
656
657/* create a queue pair within the protection domain for a link */
658int smc_ib_create_queue_pair(struct smc_link *lnk)
659{
660	int sges_per_buf = (lnk->lgr->smc_version == SMC_V2) ? 2 : 1;
661	struct ib_qp_init_attr qp_attr = {
662		.event_handler = smc_ib_qp_event_handler,
663		.qp_context = lnk,
664		.send_cq = lnk->smcibdev->roce_cq_send,
665		.recv_cq = lnk->smcibdev->roce_cq_recv,
666		.srq = NULL,
667		.cap = {
668				/* include unsolicited rdma_writes as well,
669				 * there are max. 2 RDMA_WRITE per 1 WR_SEND
670				 */
671			.max_send_wr = SMC_WR_BUF_CNT * 3,
672			.max_recv_wr = SMC_WR_BUF_CNT * 3,
673			.max_send_sge = SMC_IB_MAX_SEND_SGE,
674			.max_recv_sge = sges_per_buf,
675			.max_inline_data = 0,
676		},
677		.sq_sig_type = IB_SIGNAL_REQ_WR,
678		.qp_type = IB_QPT_RC,
679	};
680	int rc;
681
682	lnk->roce_qp = ib_create_qp(lnk->roce_pd, &qp_attr);
683	rc = PTR_ERR_OR_ZERO(lnk->roce_qp);
684	if (IS_ERR(lnk->roce_qp))
685		lnk->roce_qp = NULL;
686	else
687		smc_wr_remember_qp_attr(lnk);
688	return rc;
689}
690
691void smc_ib_put_memory_region(struct ib_mr *mr)
692{
693	ib_dereg_mr(mr);
694}
695
696static int smc_ib_map_mr_sg(struct smc_buf_desc *buf_slot, u8 link_idx)
697{
698	unsigned int offset = 0;
699	int sg_num;
700
701	/* map the largest prefix of a dma mapped SG list */
702	sg_num = ib_map_mr_sg(buf_slot->mr[link_idx],
703			      buf_slot->sgt[link_idx].sgl,
704			      buf_slot->sgt[link_idx].orig_nents,
705			      &offset, PAGE_SIZE);
706
707	return sg_num;
708}
709
710/* Allocate a memory region and map the dma mapped SG list of buf_slot */
711int smc_ib_get_memory_region(struct ib_pd *pd, int access_flags,
712			     struct smc_buf_desc *buf_slot, u8 link_idx)
713{
714	if (buf_slot->mr[link_idx])
715		return 0; /* already done */
716
717	buf_slot->mr[link_idx] =
718		ib_alloc_mr(pd, IB_MR_TYPE_MEM_REG, 1 << buf_slot->order);
719	if (IS_ERR(buf_slot->mr[link_idx])) {
720		int rc;
721
722		rc = PTR_ERR(buf_slot->mr[link_idx]);
723		buf_slot->mr[link_idx] = NULL;
724		return rc;
725	}
726
727	if (smc_ib_map_mr_sg(buf_slot, link_idx) !=
728			     buf_slot->sgt[link_idx].orig_nents)
729		return -EINVAL;
730
731	return 0;
732}
733
734bool smc_ib_is_sg_need_sync(struct smc_link *lnk,
735			    struct smc_buf_desc *buf_slot)
736{
737	struct scatterlist *sg;
738	unsigned int i;
739	bool ret = false;
740
741	/* for now there is just one DMA address */
742	for_each_sg(buf_slot->sgt[lnk->link_idx].sgl, sg,
743		    buf_slot->sgt[lnk->link_idx].nents, i) {
744		if (!sg_dma_len(sg))
745			break;
746		if (dma_need_sync(lnk->smcibdev->ibdev->dma_device,
747				  sg_dma_address(sg))) {
748			ret = true;
749			goto out;
750		}
751	}
752
753out:
754	return ret;
755}
756
757/* synchronize buffer usage for cpu access */
758void smc_ib_sync_sg_for_cpu(struct smc_link *lnk,
759			    struct smc_buf_desc *buf_slot,
760			    enum dma_data_direction data_direction)
761{
762	struct scatterlist *sg;
763	unsigned int i;
764
765	if (!(buf_slot->is_dma_need_sync & (1U << lnk->link_idx)))
766		return;
767
768	/* for now there is just one DMA address */
769	for_each_sg(buf_slot->sgt[lnk->link_idx].sgl, sg,
770		    buf_slot->sgt[lnk->link_idx].nents, i) {
771		if (!sg_dma_len(sg))
772			break;
773		ib_dma_sync_single_for_cpu(lnk->smcibdev->ibdev,
774					   sg_dma_address(sg),
775					   sg_dma_len(sg),
776					   data_direction);
777	}
778}
779
780/* synchronize buffer usage for device access */
781void smc_ib_sync_sg_for_device(struct smc_link *lnk,
782			       struct smc_buf_desc *buf_slot,
783			       enum dma_data_direction data_direction)
784{
785	struct scatterlist *sg;
786	unsigned int i;
787
788	if (!(buf_slot->is_dma_need_sync & (1U << lnk->link_idx)))
789		return;
790
791	/* for now there is just one DMA address */
792	for_each_sg(buf_slot->sgt[lnk->link_idx].sgl, sg,
793		    buf_slot->sgt[lnk->link_idx].nents, i) {
794		if (!sg_dma_len(sg))
795			break;
796		ib_dma_sync_single_for_device(lnk->smcibdev->ibdev,
797					      sg_dma_address(sg),
798					      sg_dma_len(sg),
799					      data_direction);
800	}
801}
802
803/* Map a new TX or RX buffer SG-table to DMA */
804int smc_ib_buf_map_sg(struct smc_link *lnk,
805		      struct smc_buf_desc *buf_slot,
806		      enum dma_data_direction data_direction)
807{
808	int mapped_nents;
809
810	mapped_nents = ib_dma_map_sg(lnk->smcibdev->ibdev,
811				     buf_slot->sgt[lnk->link_idx].sgl,
812				     buf_slot->sgt[lnk->link_idx].orig_nents,
813				     data_direction);
814	if (!mapped_nents)
815		return -ENOMEM;
816
817	return mapped_nents;
818}
819
820void smc_ib_buf_unmap_sg(struct smc_link *lnk,
821			 struct smc_buf_desc *buf_slot,
822			 enum dma_data_direction data_direction)
823{
824	if (!buf_slot->sgt[lnk->link_idx].sgl->dma_address)
825		return; /* already unmapped */
826
827	ib_dma_unmap_sg(lnk->smcibdev->ibdev,
828			buf_slot->sgt[lnk->link_idx].sgl,
829			buf_slot->sgt[lnk->link_idx].orig_nents,
830			data_direction);
831	buf_slot->sgt[lnk->link_idx].sgl->dma_address = 0;
832}
833
834long smc_ib_setup_per_ibdev(struct smc_ib_device *smcibdev)
835{
836	struct ib_cq_init_attr cqattr =	{
837		.cqe = SMC_MAX_CQE, .comp_vector = 0 };
838	int cqe_size_order, smc_order;
839	long rc;
840
841	mutex_lock(&smcibdev->mutex);
842	rc = 0;
843	if (smcibdev->initialized)
844		goto out;
845	/* the calculated number of cq entries fits to mlx5 cq allocation */
846	cqe_size_order = cache_line_size() == 128 ? 7 : 6;
847	smc_order = MAX_PAGE_ORDER - cqe_size_order;
848	if (SMC_MAX_CQE + 2 > (0x00000001 << smc_order) * PAGE_SIZE)
849		cqattr.cqe = (0x00000001 << smc_order) * PAGE_SIZE - 2;
850	smcibdev->roce_cq_send = ib_create_cq(smcibdev->ibdev,
851					      smc_wr_tx_cq_handler, NULL,
852					      smcibdev, &cqattr);
853	rc = PTR_ERR_OR_ZERO(smcibdev->roce_cq_send);
854	if (IS_ERR(smcibdev->roce_cq_send)) {
855		smcibdev->roce_cq_send = NULL;
856		goto out;
857	}
858	smcibdev->roce_cq_recv = ib_create_cq(smcibdev->ibdev,
859					      smc_wr_rx_cq_handler, NULL,
860					      smcibdev, &cqattr);
861	rc = PTR_ERR_OR_ZERO(smcibdev->roce_cq_recv);
862	if (IS_ERR(smcibdev->roce_cq_recv)) {
863		smcibdev->roce_cq_recv = NULL;
864		goto err;
865	}
866	smc_wr_add_dev(smcibdev);
867	smcibdev->initialized = 1;
868	goto out;
869
870err:
871	ib_destroy_cq(smcibdev->roce_cq_send);
872out:
873	mutex_unlock(&smcibdev->mutex);
874	return rc;
875}
876
877static void smc_ib_cleanup_per_ibdev(struct smc_ib_device *smcibdev)
878{
879	mutex_lock(&smcibdev->mutex);
880	if (!smcibdev->initialized)
881		goto out;
882	smcibdev->initialized = 0;
883	ib_destroy_cq(smcibdev->roce_cq_recv);
884	ib_destroy_cq(smcibdev->roce_cq_send);
885	smc_wr_remove_dev(smcibdev);
886out:
887	mutex_unlock(&smcibdev->mutex);
888}
889
890static struct ib_client smc_ib_client;
891
892static void smc_copy_netdev_ifindex(struct smc_ib_device *smcibdev, int port)
893{
894	struct ib_device *ibdev = smcibdev->ibdev;
895	struct net_device *ndev;
896
897	if (!ibdev->ops.get_netdev)
898		return;
899	ndev = ibdev->ops.get_netdev(ibdev, port + 1);
900	if (ndev) {
901		smcibdev->ndev_ifidx[port] = ndev->ifindex;
902		dev_put(ndev);
903	}
904}
905
906void smc_ib_ndev_change(struct net_device *ndev, unsigned long event)
907{
908	struct smc_ib_device *smcibdev;
909	struct ib_device *libdev;
910	struct net_device *lndev;
911	u8 port_cnt;
912	int i;
913
914	mutex_lock(&smc_ib_devices.mutex);
915	list_for_each_entry(smcibdev, &smc_ib_devices.list, list) {
916		port_cnt = smcibdev->ibdev->phys_port_cnt;
917		for (i = 0; i < min_t(size_t, port_cnt, SMC_MAX_PORTS); i++) {
918			libdev = smcibdev->ibdev;
919			if (!libdev->ops.get_netdev)
920				continue;
921			lndev = libdev->ops.get_netdev(libdev, i + 1);
922			dev_put(lndev);
923			if (lndev != ndev)
924				continue;
925			if (event == NETDEV_REGISTER)
926				smcibdev->ndev_ifidx[i] = ndev->ifindex;
927			if (event == NETDEV_UNREGISTER)
928				smcibdev->ndev_ifidx[i] = 0;
929		}
930	}
931	mutex_unlock(&smc_ib_devices.mutex);
932}
933
934/* callback function for ib_register_client() */
935static int smc_ib_add_dev(struct ib_device *ibdev)
936{
937	struct smc_ib_device *smcibdev;
938	u8 port_cnt;
939	int i;
940
941	if (ibdev->node_type != RDMA_NODE_IB_CA)
942		return -EOPNOTSUPP;
943
944	smcibdev = kzalloc(sizeof(*smcibdev), GFP_KERNEL);
945	if (!smcibdev)
946		return -ENOMEM;
947
948	smcibdev->ibdev = ibdev;
949	INIT_WORK(&smcibdev->port_event_work, smc_ib_port_event_work);
950	atomic_set(&smcibdev->lnk_cnt, 0);
951	init_waitqueue_head(&smcibdev->lnks_deleted);
952	mutex_init(&smcibdev->mutex);
953	mutex_lock(&smc_ib_devices.mutex);
954	list_add_tail(&smcibdev->list, &smc_ib_devices.list);
955	mutex_unlock(&smc_ib_devices.mutex);
956	ib_set_client_data(ibdev, &smc_ib_client, smcibdev);
957	INIT_IB_EVENT_HANDLER(&smcibdev->event_handler, smcibdev->ibdev,
958			      smc_ib_global_event_handler);
959	ib_register_event_handler(&smcibdev->event_handler);
960
961	/* trigger reading of the port attributes */
962	port_cnt = smcibdev->ibdev->phys_port_cnt;
963	pr_warn_ratelimited("smc: adding ib device %s with port count %d\n",
964			    smcibdev->ibdev->name, port_cnt);
965	for (i = 0;
966	     i < min_t(size_t, port_cnt, SMC_MAX_PORTS);
967	     i++) {
968		set_bit(i, &smcibdev->port_event_mask);
969		/* determine pnetids of the port */
970		if (smc_pnetid_by_dev_port(ibdev->dev.parent, i,
971					   smcibdev->pnetid[i]))
972			smc_pnetid_by_table_ib(smcibdev, i + 1);
973		smc_copy_netdev_ifindex(smcibdev, i);
974		pr_warn_ratelimited("smc:    ib device %s port %d has pnetid "
975				    "%.16s%s\n",
976				    smcibdev->ibdev->name, i + 1,
977				    smcibdev->pnetid[i],
978				    smcibdev->pnetid_by_user[i] ?
979				     " (user defined)" :
980				     "");
981	}
982	schedule_work(&smcibdev->port_event_work);
983	return 0;
984}
985
986/* callback function for ib_unregister_client() */
987static void smc_ib_remove_dev(struct ib_device *ibdev, void *client_data)
988{
989	struct smc_ib_device *smcibdev = client_data;
990
991	mutex_lock(&smc_ib_devices.mutex);
992	list_del_init(&smcibdev->list); /* remove from smc_ib_devices */
993	mutex_unlock(&smc_ib_devices.mutex);
994	pr_warn_ratelimited("smc: removing ib device %s\n",
995			    smcibdev->ibdev->name);
996	smc_smcr_terminate_all(smcibdev);
997	smc_ib_cleanup_per_ibdev(smcibdev);
998	ib_unregister_event_handler(&smcibdev->event_handler);
999	cancel_work_sync(&smcibdev->port_event_work);
1000	kfree(smcibdev);
1001}
1002
1003static struct ib_client smc_ib_client = {
1004	.name	= "smc_ib",
1005	.add	= smc_ib_add_dev,
1006	.remove = smc_ib_remove_dev,
1007};
1008
1009int __init smc_ib_register_client(void)
1010{
1011	smc_ib_init_local_systemid();
1012	return ib_register_client(&smc_ib_client);
1013}
1014
1015void smc_ib_unregister_client(void)
1016{
1017	ib_unregister_client(&smc_ib_client);
1018}
1019