xref: /openbmc/linux/drivers/infiniband/hw/hfi1/opfn.c (revision f01b4d5a43da47a9f61618a81a4ff3258ddc2c01)
1 // SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
2 /*
3  * Copyright(c) 2018 Intel Corporation.
4  *
5  */
6 #include "hfi.h"
7 #include "trace.h"
8 #include "qp.h"
9 #include "opfn.h"
10 
11 #define IB_BTHE_E                 BIT(IB_BTHE_E_SHIFT)
12 
13 #define OPFN_CODE(code) BIT((code) - 1)
14 #define OPFN_MASK(code) OPFN_CODE(STL_VERBS_EXTD_##code)
15 
16 struct hfi1_opfn_type {
17 	bool (*request)(struct rvt_qp *qp, u64 *data);
18 	bool (*response)(struct rvt_qp *qp, u64 *data);
19 	bool (*reply)(struct rvt_qp *qp, u64 data);
20 	void (*error)(struct rvt_qp *qp);
21 };
22 
23 static struct hfi1_opfn_type hfi1_opfn_handlers[STL_VERBS_EXTD_MAX] = {
24 	[STL_VERBS_EXTD_TID_RDMA] = {
25 		.request = tid_rdma_conn_req,
26 		.response = tid_rdma_conn_resp,
27 		.reply = tid_rdma_conn_reply,
28 		.error = tid_rdma_conn_error,
29 	},
30 };
31 
32 static struct workqueue_struct *opfn_wq;
33 
34 static void opfn_schedule_conn_request(struct rvt_qp *qp);
35 
36 static bool hfi1_opfn_extended(u32 bth1)
37 {
38 	return !!(bth1 & IB_BTHE_E);
39 }
40 
41 static void opfn_conn_request(struct rvt_qp *qp)
42 {
43 	struct hfi1_qp_priv *priv = qp->priv;
44 	struct ib_atomic_wr wr;
45 	u16 mask, capcode;
46 	struct hfi1_opfn_type *extd;
47 	u64 data;
48 	unsigned long flags;
49 	int ret = 0;
50 
51 	spin_lock_irqsave(&priv->opfn.lock, flags);
52 	/*
53 	 * Exit if the extended bit is not set, or if nothing is requested, or
54 	 * if we have completed all requests, or if a previous request is in
55 	 * progress
56 	 */
57 	if (!priv->opfn.extended || !priv->opfn.requested ||
58 	    priv->opfn.requested == priv->opfn.completed || priv->opfn.curr)
59 		goto done;
60 
61 	mask = priv->opfn.requested & ~priv->opfn.completed;
62 	capcode = ilog2(mask & ~(mask - 1)) + 1;
63 	if (capcode >= STL_VERBS_EXTD_MAX) {
64 		priv->opfn.completed |= OPFN_CODE(capcode);
65 		goto done;
66 	}
67 
68 	extd = &hfi1_opfn_handlers[capcode];
69 	if (!extd || !extd->request || !extd->request(qp, &data)) {
70 		/*
71 		 * Either there is no handler for this capability or the request
72 		 * packet could not be generated. Either way, mark it as done so
73 		 * we don't keep attempting to complete it.
74 		 */
75 		priv->opfn.completed |= OPFN_CODE(capcode);
76 		goto done;
77 	}
78 
79 	data = (data & ~0xf) | capcode;
80 
81 	memset(&wr, 0, sizeof(wr));
82 	wr.wr.opcode = IB_WR_OPFN;
83 	wr.remote_addr = HFI1_VERBS_E_ATOMIC_VADDR;
84 	wr.compare_add = data;
85 
86 	priv->opfn.curr = capcode;	/* A new request is now in progress */
87 	/* Drop opfn.lock before calling ib_post_send() */
88 	spin_unlock_irqrestore(&priv->opfn.lock, flags);
89 
90 	ret = ib_post_send(&qp->ibqp, &wr.wr, NULL);
91 	if (ret)
92 		goto err;
93 	return;
94 err:
95 	spin_lock_irqsave(&priv->opfn.lock, flags);
96 	/*
97 	 * In case of an unexpected error return from ib_post_send
98 	 * clear opfn.curr and reschedule to try again
99 	 */
100 	priv->opfn.curr = STL_VERBS_EXTD_NONE;
101 	opfn_schedule_conn_request(qp);
102 done:
103 	spin_unlock_irqrestore(&priv->opfn.lock, flags);
104 }
105 
106 void opfn_send_conn_request(struct work_struct *work)
107 {
108 	struct hfi1_opfn_data *od;
109 	struct hfi1_qp_priv *qpriv;
110 
111 	od = container_of(work, struct hfi1_opfn_data, opfn_work);
112 	qpriv = container_of(od, struct hfi1_qp_priv, opfn);
113 
114 	opfn_conn_request(qpriv->owner);
115 }
116 
117 /*
118  * When QP s_lock is held in the caller, the OPFN request must be scheduled
119  * to a different workqueue to avoid double locking QP s_lock in call to
120  * ib_post_send in opfn_conn_request
121  */
122 static void opfn_schedule_conn_request(struct rvt_qp *qp)
123 {
124 	struct hfi1_qp_priv *priv = qp->priv;
125 
126 	queue_work(opfn_wq, &priv->opfn.opfn_work);
127 }
128 
129 void opfn_conn_response(struct rvt_qp *qp, struct rvt_ack_entry *e,
130 			struct ib_atomic_eth *ateth)
131 {
132 	struct hfi1_qp_priv *priv = qp->priv;
133 	u64 data = be64_to_cpu(ateth->compare_data);
134 	struct hfi1_opfn_type *extd;
135 	u8 capcode;
136 	unsigned long flags;
137 
138 	capcode = data & 0xf;
139 	if (!capcode || capcode >= STL_VERBS_EXTD_MAX)
140 		return;
141 
142 	extd = &hfi1_opfn_handlers[capcode];
143 
144 	if (!extd || !extd->response) {
145 		e->atomic_data = capcode;
146 		return;
147 	}
148 
149 	spin_lock_irqsave(&priv->opfn.lock, flags);
150 	if (priv->opfn.completed & OPFN_CODE(capcode)) {
151 		/*
152 		 * We are receiving a request for a feature that has already
153 		 * been negotiated. This may mean that the other side has reset
154 		 */
155 		priv->opfn.completed &= ~OPFN_CODE(capcode);
156 		if (extd->error)
157 			extd->error(qp);
158 	}
159 
160 	if (extd->response(qp, &data))
161 		priv->opfn.completed |= OPFN_CODE(capcode);
162 	e->atomic_data = (data & ~0xf) | capcode;
163 	spin_unlock_irqrestore(&priv->opfn.lock, flags);
164 }
165 
166 void opfn_conn_reply(struct rvt_qp *qp, u64 data)
167 {
168 	struct hfi1_qp_priv *priv = qp->priv;
169 	struct hfi1_opfn_type *extd;
170 	u8 capcode;
171 	unsigned long flags;
172 
173 	capcode = data & 0xf;
174 	if (!capcode || capcode >= STL_VERBS_EXTD_MAX)
175 		return;
176 
177 	spin_lock_irqsave(&priv->opfn.lock, flags);
178 	/*
179 	 * Either there is no previous request or the reply is not for the
180 	 * current request
181 	 */
182 	if (!priv->opfn.curr || capcode != priv->opfn.curr)
183 		goto done;
184 
185 	extd = &hfi1_opfn_handlers[capcode];
186 
187 	if (!extd || !extd->reply)
188 		goto clear;
189 
190 	if (extd->reply(qp, data))
191 		priv->opfn.completed |= OPFN_CODE(capcode);
192 clear:
193 	/*
194 	 * Clear opfn.curr to indicate that the previous request is no longer in
195 	 * progress
196 	 */
197 	priv->opfn.curr = STL_VERBS_EXTD_NONE;
198 done:
199 	spin_unlock_irqrestore(&priv->opfn.lock, flags);
200 }
201 
202 void opfn_conn_error(struct rvt_qp *qp)
203 {
204 	struct hfi1_qp_priv *priv = qp->priv;
205 	struct hfi1_opfn_type *extd = NULL;
206 	unsigned long flags;
207 	u16 capcode;
208 
209 	/*
210 	 * The QP has gone into the Error state. We have to invalidate all
211 	 * negotiated feature, including the one in progress (if any). The RC
212 	 * QP handling will clean the WQE for the connection request.
213 	 */
214 	spin_lock_irqsave(&priv->opfn.lock, flags);
215 	while (priv->opfn.completed) {
216 		capcode = priv->opfn.completed & ~(priv->opfn.completed - 1);
217 		extd = &hfi1_opfn_handlers[ilog2(capcode) + 1];
218 		if (extd->error)
219 			extd->error(qp);
220 		priv->opfn.completed &= ~OPFN_CODE(capcode);
221 	}
222 	priv->opfn.extended = 0;
223 	priv->opfn.requested = 0;
224 	priv->opfn.curr = STL_VERBS_EXTD_NONE;
225 	spin_unlock_irqrestore(&priv->opfn.lock, flags);
226 }
227 
228 void opfn_qp_init(struct rvt_qp *qp, struct ib_qp_attr *attr, int attr_mask)
229 {
230 	struct ib_qp *ibqp = &qp->ibqp;
231 	struct hfi1_qp_priv *priv = qp->priv;
232 	unsigned long flags;
233 
234 	spin_lock_irqsave(&priv->opfn.lock, flags);
235 	if (ibqp->qp_type == IB_QPT_RC && HFI1_CAP_IS_KSET(TID_RDMA)) {
236 		struct tid_rdma_params *local = &priv->tid_rdma.local;
237 
238 		if (qp->pmtu == enum_to_mtu(OPA_MTU_4096) ||
239 		    qp->pmtu == enum_to_mtu(OPA_MTU_8192)) {
240 			tid_rdma_opfn_init(qp, local);
241 			/*
242 			 * We only want to set the OPFN requested bit when the
243 			 * QP transitions to RTS.
244 			 */
245 			if (attr_mask & IB_QP_STATE &&
246 			    attr->qp_state == IB_QPS_RTS) {
247 				priv->opfn.requested |= OPFN_MASK(TID_RDMA);
248 				/*
249 				 * If the QP is transitioning to RTS and the
250 				 * opfn.completed for TID RDMA has already been
251 				 * set, the QP is being moved *back* into RTS.
252 				 * We can now renegotiate the TID RDMA
253 				 * parameters.
254 				 */
255 				if (priv->opfn.completed &
256 				    OPFN_MASK(TID_RDMA)) {
257 					priv->opfn.completed &=
258 						~OPFN_MASK(TID_RDMA);
259 					/*
260 					 * Since the opfn.completed bit was
261 					 * already set, it is safe to assume
262 					 * that the opfn.extended is also set.
263 					 */
264 					opfn_schedule_conn_request(qp);
265 				}
266 			}
267 		} else {
268 			memset(local, 0, sizeof(*local));
269 		}
270 	}
271 	spin_unlock_irqrestore(&priv->opfn.lock, flags);
272 }
273 
274 void opfn_trigger_conn_request(struct rvt_qp *qp, u32 bth1)
275 {
276 	struct hfi1_qp_priv *priv = qp->priv;
277 
278 	if (!priv->opfn.extended && hfi1_opfn_extended(bth1) &&
279 	    HFI1_CAP_IS_KSET(OPFN)) {
280 		priv->opfn.extended = 1;
281 		if (qp->state == IB_QPS_RTS)
282 			opfn_conn_request(qp);
283 	}
284 }
285 
286 int opfn_init(void)
287 {
288 	opfn_wq = alloc_workqueue("hfi_opfn",
289 				  WQ_SYSFS | WQ_HIGHPRI | WQ_CPU_INTENSIVE |
290 				  WQ_MEM_RECLAIM,
291 				  HFI1_MAX_ACTIVE_WORKQUEUE_ENTRIES);
292 	if (!opfn_wq)
293 		return -ENOMEM;
294 
295 	return 0;
296 }
297 
298 void opfn_exit(void)
299 {
300 	if (opfn_wq) {
301 		destroy_workqueue(opfn_wq);
302 		opfn_wq = NULL;
303 	}
304 }
305