xref: /kernel/linux/linux-5.10/net/smc/smc_wr.c (revision 8c2ecf20)
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Shared Memory Communications over RDMA (SMC-R) and RoCE
4 *
5 * Work Requests exploiting Infiniband API
6 *
7 * Work requests (WR) of type ib_post_send or ib_post_recv respectively
8 * are submitted to either RC SQ or RC RQ respectively
9 * (reliably connected send/receive queue)
10 * and become work queue entries (WQEs).
11 * While an SQ WR/WQE is pending, we track it until transmission completion.
12 * Through a send or receive completion queue (CQ) respectively,
13 * we get completion queue entries (CQEs) [aka work completions (WCs)].
14 * Since the CQ callback is called from IRQ context, we split work by using
15 * bottom halves implemented by tasklets.
16 *
17 * SMC uses this to exchange LLC (link layer control)
18 * and CDC (connection data control) messages.
19 *
20 * Copyright IBM Corp. 2016
21 *
22 * Author(s):  Steffen Maier <maier@linux.vnet.ibm.com>
23 */
24
25#include <linux/atomic.h>
26#include <linux/hashtable.h>
27#include <linux/wait.h>
28#include <rdma/ib_verbs.h>
29#include <asm/div64.h>
30
31#include "smc.h"
32#include "smc_wr.h"
33
34#define SMC_WR_MAX_POLL_CQE 10	/* max. # of compl. queue elements in 1 poll */
35
36#define SMC_WR_RX_HASH_BITS 4
37static DEFINE_HASHTABLE(smc_wr_rx_hash, SMC_WR_RX_HASH_BITS);
38static DEFINE_SPINLOCK(smc_wr_rx_hash_lock);
39
40struct smc_wr_tx_pend {	/* control data for a pending send request */
41	u64			wr_id;		/* work request id sent */
42	smc_wr_tx_handler	handler;
43	enum ib_wc_status	wc_status;	/* CQE status */
44	struct smc_link		*link;
45	u32			idx;
46	struct smc_wr_tx_pend_priv priv;
47	u8			compl_requested;
48};
49
50/******************************** send queue *********************************/
51
52/*------------------------------- completion --------------------------------*/
53
54/* returns true if at least one tx work request is pending on the given link */
55static inline bool smc_wr_is_tx_pend(struct smc_link *link)
56{
57	if (find_first_bit(link->wr_tx_mask, link->wr_tx_cnt) !=
58							link->wr_tx_cnt) {
59		return true;
60	}
61	return false;
62}
63
64/* wait till all pending tx work requests on the given link are completed */
65void smc_wr_tx_wait_no_pending_sends(struct smc_link *link)
66{
67	wait_event(link->wr_tx_wait, !smc_wr_is_tx_pend(link));
68}
69
70static inline int smc_wr_tx_find_pending_index(struct smc_link *link, u64 wr_id)
71{
72	u32 i;
73
74	for (i = 0; i < link->wr_tx_cnt; i++) {
75		if (link->wr_tx_pends[i].wr_id == wr_id)
76			return i;
77	}
78	return link->wr_tx_cnt;
79}
80
81static inline void smc_wr_tx_process_cqe(struct ib_wc *wc)
82{
83	struct smc_wr_tx_pend pnd_snd;
84	struct smc_link *link;
85	u32 pnd_snd_idx;
86
87	link = wc->qp->qp_context;
88
89	if (wc->opcode == IB_WC_REG_MR) {
90		if (wc->status)
91			link->wr_reg_state = FAILED;
92		else
93			link->wr_reg_state = CONFIRMED;
94		smc_wr_wakeup_reg_wait(link);
95		return;
96	}
97
98	pnd_snd_idx = smc_wr_tx_find_pending_index(link, wc->wr_id);
99	if (pnd_snd_idx == link->wr_tx_cnt)
100		return;
101	link->wr_tx_pends[pnd_snd_idx].wc_status = wc->status;
102	if (link->wr_tx_pends[pnd_snd_idx].compl_requested)
103		complete(&link->wr_tx_compl[pnd_snd_idx]);
104	memcpy(&pnd_snd, &link->wr_tx_pends[pnd_snd_idx], sizeof(pnd_snd));
105	/* clear the full struct smc_wr_tx_pend including .priv */
106	memset(&link->wr_tx_pends[pnd_snd_idx], 0,
107	       sizeof(link->wr_tx_pends[pnd_snd_idx]));
108	memset(&link->wr_tx_bufs[pnd_snd_idx], 0,
109	       sizeof(link->wr_tx_bufs[pnd_snd_idx]));
110	if (!test_and_clear_bit(pnd_snd_idx, link->wr_tx_mask))
111		return;
112	if (wc->status) {
113		/* terminate link */
114		smcr_link_down_cond_sched(link);
115	}
116	if (pnd_snd.handler)
117		pnd_snd.handler(&pnd_snd.priv, link, wc->status);
118	wake_up(&link->wr_tx_wait);
119}
120
121static void smc_wr_tx_tasklet_fn(unsigned long data)
122{
123	struct smc_ib_device *dev = (struct smc_ib_device *)data;
124	struct ib_wc wc[SMC_WR_MAX_POLL_CQE];
125	int i = 0, rc;
126	int polled = 0;
127
128again:
129	polled++;
130	do {
131		memset(&wc, 0, sizeof(wc));
132		rc = ib_poll_cq(dev->roce_cq_send, SMC_WR_MAX_POLL_CQE, wc);
133		if (polled == 1) {
134			ib_req_notify_cq(dev->roce_cq_send,
135					 IB_CQ_NEXT_COMP |
136					 IB_CQ_REPORT_MISSED_EVENTS);
137		}
138		if (!rc)
139			break;
140		for (i = 0; i < rc; i++)
141			smc_wr_tx_process_cqe(&wc[i]);
142	} while (rc > 0);
143	if (polled == 1)
144		goto again;
145}
146
147void smc_wr_tx_cq_handler(struct ib_cq *ib_cq, void *cq_context)
148{
149	struct smc_ib_device *dev = (struct smc_ib_device *)cq_context;
150
151	tasklet_schedule(&dev->send_tasklet);
152}
153
154/*---------------------------- request submission ---------------------------*/
155
156static inline int smc_wr_tx_get_free_slot_index(struct smc_link *link, u32 *idx)
157{
158	*idx = link->wr_tx_cnt;
159	if (!smc_link_sendable(link))
160		return -ENOLINK;
161	for_each_clear_bit(*idx, link->wr_tx_mask, link->wr_tx_cnt) {
162		if (!test_and_set_bit(*idx, link->wr_tx_mask))
163			return 0;
164	}
165	*idx = link->wr_tx_cnt;
166	return -EBUSY;
167}
168
169/**
170 * smc_wr_tx_get_free_slot() - returns buffer for message assembly,
171 *			and sets info for pending transmit tracking
172 * @link:		Pointer to smc_link used to later send the message.
173 * @handler:		Send completion handler function pointer.
174 * @wr_buf:		Out value returns pointer to message buffer.
175 * @wr_rdma_buf:	Out value returns pointer to rdma work request.
176 * @wr_pend_priv:	Out value returns pointer serving as handler context.
177 *
178 * Return: 0 on success, or -errno on error.
179 */
180int smc_wr_tx_get_free_slot(struct smc_link *link,
181			    smc_wr_tx_handler handler,
182			    struct smc_wr_buf **wr_buf,
183			    struct smc_rdma_wr **wr_rdma_buf,
184			    struct smc_wr_tx_pend_priv **wr_pend_priv)
185{
186	struct smc_link_group *lgr = smc_get_lgr(link);
187	struct smc_wr_tx_pend *wr_pend;
188	u32 idx = link->wr_tx_cnt;
189	struct ib_send_wr *wr_ib;
190	u64 wr_id;
191	int rc;
192
193	*wr_buf = NULL;
194	*wr_pend_priv = NULL;
195	if (in_softirq() || lgr->terminating) {
196		rc = smc_wr_tx_get_free_slot_index(link, &idx);
197		if (rc)
198			return rc;
199	} else {
200		rc = wait_event_interruptible_timeout(
201			link->wr_tx_wait,
202			!smc_link_sendable(link) ||
203			lgr->terminating ||
204			(smc_wr_tx_get_free_slot_index(link, &idx) != -EBUSY),
205			SMC_WR_TX_WAIT_FREE_SLOT_TIME);
206		if (!rc) {
207			/* timeout - terminate link */
208			smcr_link_down_cond_sched(link);
209			return -EPIPE;
210		}
211		if (idx == link->wr_tx_cnt)
212			return -EPIPE;
213	}
214	wr_id = smc_wr_tx_get_next_wr_id(link);
215	wr_pend = &link->wr_tx_pends[idx];
216	wr_pend->wr_id = wr_id;
217	wr_pend->handler = handler;
218	wr_pend->link = link;
219	wr_pend->idx = idx;
220	wr_ib = &link->wr_tx_ibs[idx];
221	wr_ib->wr_id = wr_id;
222	*wr_buf = &link->wr_tx_bufs[idx];
223	if (wr_rdma_buf)
224		*wr_rdma_buf = &link->wr_tx_rdmas[idx];
225	*wr_pend_priv = &wr_pend->priv;
226	return 0;
227}
228
229int smc_wr_tx_put_slot(struct smc_link *link,
230		       struct smc_wr_tx_pend_priv *wr_pend_priv)
231{
232	struct smc_wr_tx_pend *pend;
233
234	pend = container_of(wr_pend_priv, struct smc_wr_tx_pend, priv);
235	if (pend->idx < link->wr_tx_cnt) {
236		u32 idx = pend->idx;
237
238		/* clear the full struct smc_wr_tx_pend including .priv */
239		memset(&link->wr_tx_pends[idx], 0,
240		       sizeof(link->wr_tx_pends[idx]));
241		memset(&link->wr_tx_bufs[idx], 0,
242		       sizeof(link->wr_tx_bufs[idx]));
243		test_and_clear_bit(idx, link->wr_tx_mask);
244		wake_up(&link->wr_tx_wait);
245		return 1;
246	}
247
248	return 0;
249}
250
251/* Send prepared WR slot via ib_post_send.
252 * @priv: pointer to smc_wr_tx_pend_priv identifying prepared message buffer
253 */
254int smc_wr_tx_send(struct smc_link *link, struct smc_wr_tx_pend_priv *priv)
255{
256	struct smc_wr_tx_pend *pend;
257	int rc;
258
259	ib_req_notify_cq(link->smcibdev->roce_cq_send,
260			 IB_CQ_NEXT_COMP | IB_CQ_REPORT_MISSED_EVENTS);
261	pend = container_of(priv, struct smc_wr_tx_pend, priv);
262	rc = ib_post_send(link->roce_qp, &link->wr_tx_ibs[pend->idx], NULL);
263	if (rc) {
264		smc_wr_tx_put_slot(link, priv);
265		smcr_link_down_cond_sched(link);
266	}
267	return rc;
268}
269
270/* Send prepared WR slot via ib_post_send and wait for send completion
271 * notification.
272 * @priv: pointer to smc_wr_tx_pend_priv identifying prepared message buffer
273 */
274int smc_wr_tx_send_wait(struct smc_link *link, struct smc_wr_tx_pend_priv *priv,
275			unsigned long timeout)
276{
277	struct smc_wr_tx_pend *pend;
278	u32 pnd_idx;
279	int rc;
280
281	pend = container_of(priv, struct smc_wr_tx_pend, priv);
282	pend->compl_requested = 1;
283	pnd_idx = pend->idx;
284	init_completion(&link->wr_tx_compl[pnd_idx]);
285
286	rc = smc_wr_tx_send(link, priv);
287	if (rc)
288		return rc;
289	/* wait for completion by smc_wr_tx_process_cqe() */
290	rc = wait_for_completion_interruptible_timeout(
291					&link->wr_tx_compl[pnd_idx], timeout);
292	if (rc <= 0)
293		rc = -ENODATA;
294	if (rc > 0)
295		rc = 0;
296	return rc;
297}
298
299/* Register a memory region and wait for result. */
300int smc_wr_reg_send(struct smc_link *link, struct ib_mr *mr)
301{
302	int rc;
303
304	ib_req_notify_cq(link->smcibdev->roce_cq_send,
305			 IB_CQ_NEXT_COMP | IB_CQ_REPORT_MISSED_EVENTS);
306	link->wr_reg_state = POSTED;
307	link->wr_reg.wr.wr_id = (u64)(uintptr_t)mr;
308	link->wr_reg.mr = mr;
309	link->wr_reg.key = mr->rkey;
310	rc = ib_post_send(link->roce_qp, &link->wr_reg.wr, NULL);
311	if (rc)
312		return rc;
313
314	atomic_inc(&link->wr_reg_refcnt);
315	rc = wait_event_interruptible_timeout(link->wr_reg_wait,
316					      (link->wr_reg_state != POSTED),
317					      SMC_WR_REG_MR_WAIT_TIME);
318	if (atomic_dec_and_test(&link->wr_reg_refcnt))
319		wake_up_all(&link->wr_reg_wait);
320	if (!rc) {
321		/* timeout - terminate link */
322		smcr_link_down_cond_sched(link);
323		return -EPIPE;
324	}
325	if (rc == -ERESTARTSYS)
326		return -EINTR;
327	switch (link->wr_reg_state) {
328	case CONFIRMED:
329		rc = 0;
330		break;
331	case FAILED:
332		rc = -EIO;
333		break;
334	case POSTED:
335		rc = -EPIPE;
336		break;
337	}
338	return rc;
339}
340
341/****************************** receive queue ********************************/
342
343int smc_wr_rx_register_handler(struct smc_wr_rx_handler *handler)
344{
345	struct smc_wr_rx_handler *h_iter;
346	int rc = 0;
347
348	spin_lock(&smc_wr_rx_hash_lock);
349	hash_for_each_possible(smc_wr_rx_hash, h_iter, list, handler->type) {
350		if (h_iter->type == handler->type) {
351			rc = -EEXIST;
352			goto out_unlock;
353		}
354	}
355	hash_add(smc_wr_rx_hash, &handler->list, handler->type);
356out_unlock:
357	spin_unlock(&smc_wr_rx_hash_lock);
358	return rc;
359}
360
361/* Demultiplex a received work request based on the message type to its handler.
362 * Relies on smc_wr_rx_hash having been completely filled before any IB WRs,
363 * and not being modified any more afterwards so we don't need to lock it.
364 */
365static inline void smc_wr_rx_demultiplex(struct ib_wc *wc)
366{
367	struct smc_link *link = (struct smc_link *)wc->qp->qp_context;
368	struct smc_wr_rx_handler *handler;
369	struct smc_wr_rx_hdr *wr_rx;
370	u64 temp_wr_id;
371	u32 index;
372
373	if (wc->byte_len < sizeof(*wr_rx))
374		return; /* short message */
375	temp_wr_id = wc->wr_id;
376	index = do_div(temp_wr_id, link->wr_rx_cnt);
377	wr_rx = (struct smc_wr_rx_hdr *)&link->wr_rx_bufs[index];
378	hash_for_each_possible(smc_wr_rx_hash, handler, list, wr_rx->type) {
379		if (handler->type == wr_rx->type)
380			handler->handler(wc, wr_rx);
381	}
382}
383
384static inline void smc_wr_rx_process_cqes(struct ib_wc wc[], int num)
385{
386	struct smc_link *link;
387	int i;
388
389	for (i = 0; i < num; i++) {
390		link = wc[i].qp->qp_context;
391		if (wc[i].status == IB_WC_SUCCESS) {
392			link->wr_rx_tstamp = jiffies;
393			smc_wr_rx_demultiplex(&wc[i]);
394			smc_wr_rx_post(link); /* refill WR RX */
395		} else {
396			/* handle status errors */
397			switch (wc[i].status) {
398			case IB_WC_RETRY_EXC_ERR:
399			case IB_WC_RNR_RETRY_EXC_ERR:
400			case IB_WC_WR_FLUSH_ERR:
401				smcr_link_down_cond_sched(link);
402				break;
403			default:
404				smc_wr_rx_post(link); /* refill WR RX */
405				break;
406			}
407		}
408	}
409}
410
411static void smc_wr_rx_tasklet_fn(unsigned long data)
412{
413	struct smc_ib_device *dev = (struct smc_ib_device *)data;
414	struct ib_wc wc[SMC_WR_MAX_POLL_CQE];
415	int polled = 0;
416	int rc;
417
418again:
419	polled++;
420	do {
421		memset(&wc, 0, sizeof(wc));
422		rc = ib_poll_cq(dev->roce_cq_recv, SMC_WR_MAX_POLL_CQE, wc);
423		if (polled == 1) {
424			ib_req_notify_cq(dev->roce_cq_recv,
425					 IB_CQ_SOLICITED_MASK
426					 | IB_CQ_REPORT_MISSED_EVENTS);
427		}
428		if (!rc)
429			break;
430		smc_wr_rx_process_cqes(&wc[0], rc);
431	} while (rc > 0);
432	if (polled == 1)
433		goto again;
434}
435
436void smc_wr_rx_cq_handler(struct ib_cq *ib_cq, void *cq_context)
437{
438	struct smc_ib_device *dev = (struct smc_ib_device *)cq_context;
439
440	tasklet_schedule(&dev->recv_tasklet);
441}
442
443int smc_wr_rx_post_init(struct smc_link *link)
444{
445	u32 i;
446	int rc = 0;
447
448	for (i = 0; i < link->wr_rx_cnt; i++)
449		rc = smc_wr_rx_post(link);
450	return rc;
451}
452
453/***************************** init, exit, misc ******************************/
454
455void smc_wr_remember_qp_attr(struct smc_link *lnk)
456{
457	struct ib_qp_attr *attr = &lnk->qp_attr;
458	struct ib_qp_init_attr init_attr;
459
460	memset(attr, 0, sizeof(*attr));
461	memset(&init_attr, 0, sizeof(init_attr));
462	ib_query_qp(lnk->roce_qp, attr,
463		    IB_QP_STATE |
464		    IB_QP_CUR_STATE |
465		    IB_QP_PKEY_INDEX |
466		    IB_QP_PORT |
467		    IB_QP_QKEY |
468		    IB_QP_AV |
469		    IB_QP_PATH_MTU |
470		    IB_QP_TIMEOUT |
471		    IB_QP_RETRY_CNT |
472		    IB_QP_RNR_RETRY |
473		    IB_QP_RQ_PSN |
474		    IB_QP_ALT_PATH |
475		    IB_QP_MIN_RNR_TIMER |
476		    IB_QP_SQ_PSN |
477		    IB_QP_PATH_MIG_STATE |
478		    IB_QP_CAP |
479		    IB_QP_DEST_QPN,
480		    &init_attr);
481
482	lnk->wr_tx_cnt = min_t(size_t, SMC_WR_BUF_CNT,
483			       lnk->qp_attr.cap.max_send_wr);
484	lnk->wr_rx_cnt = min_t(size_t, SMC_WR_BUF_CNT * 3,
485			       lnk->qp_attr.cap.max_recv_wr);
486}
487
488static void smc_wr_init_sge(struct smc_link *lnk)
489{
490	u32 i;
491
492	for (i = 0; i < lnk->wr_tx_cnt; i++) {
493		lnk->wr_tx_sges[i].addr =
494			lnk->wr_tx_dma_addr + i * SMC_WR_BUF_SIZE;
495		lnk->wr_tx_sges[i].length = SMC_WR_TX_SIZE;
496		lnk->wr_tx_sges[i].lkey = lnk->roce_pd->local_dma_lkey;
497		lnk->wr_tx_rdma_sges[i].tx_rdma_sge[0].wr_tx_rdma_sge[0].lkey =
498			lnk->roce_pd->local_dma_lkey;
499		lnk->wr_tx_rdma_sges[i].tx_rdma_sge[0].wr_tx_rdma_sge[1].lkey =
500			lnk->roce_pd->local_dma_lkey;
501		lnk->wr_tx_rdma_sges[i].tx_rdma_sge[1].wr_tx_rdma_sge[0].lkey =
502			lnk->roce_pd->local_dma_lkey;
503		lnk->wr_tx_rdma_sges[i].tx_rdma_sge[1].wr_tx_rdma_sge[1].lkey =
504			lnk->roce_pd->local_dma_lkey;
505		lnk->wr_tx_ibs[i].next = NULL;
506		lnk->wr_tx_ibs[i].sg_list = &lnk->wr_tx_sges[i];
507		lnk->wr_tx_ibs[i].num_sge = 1;
508		lnk->wr_tx_ibs[i].opcode = IB_WR_SEND;
509		lnk->wr_tx_ibs[i].send_flags =
510			IB_SEND_SIGNALED | IB_SEND_SOLICITED;
511		lnk->wr_tx_rdmas[i].wr_tx_rdma[0].wr.opcode = IB_WR_RDMA_WRITE;
512		lnk->wr_tx_rdmas[i].wr_tx_rdma[1].wr.opcode = IB_WR_RDMA_WRITE;
513		lnk->wr_tx_rdmas[i].wr_tx_rdma[0].wr.sg_list =
514			lnk->wr_tx_rdma_sges[i].tx_rdma_sge[0].wr_tx_rdma_sge;
515		lnk->wr_tx_rdmas[i].wr_tx_rdma[1].wr.sg_list =
516			lnk->wr_tx_rdma_sges[i].tx_rdma_sge[1].wr_tx_rdma_sge;
517	}
518	for (i = 0; i < lnk->wr_rx_cnt; i++) {
519		lnk->wr_rx_sges[i].addr =
520			lnk->wr_rx_dma_addr + i * SMC_WR_BUF_SIZE;
521		lnk->wr_rx_sges[i].length = SMC_WR_BUF_SIZE;
522		lnk->wr_rx_sges[i].lkey = lnk->roce_pd->local_dma_lkey;
523		lnk->wr_rx_ibs[i].next = NULL;
524		lnk->wr_rx_ibs[i].sg_list = &lnk->wr_rx_sges[i];
525		lnk->wr_rx_ibs[i].num_sge = 1;
526	}
527	lnk->wr_reg.wr.next = NULL;
528	lnk->wr_reg.wr.num_sge = 0;
529	lnk->wr_reg.wr.send_flags = IB_SEND_SIGNALED;
530	lnk->wr_reg.wr.opcode = IB_WR_REG_MR;
531	lnk->wr_reg.access = IB_ACCESS_LOCAL_WRITE | IB_ACCESS_REMOTE_WRITE;
532}
533
534void smc_wr_free_link(struct smc_link *lnk)
535{
536	struct ib_device *ibdev;
537
538	if (!lnk->smcibdev)
539		return;
540	ibdev = lnk->smcibdev->ibdev;
541
542	smc_wr_wakeup_reg_wait(lnk);
543	smc_wr_wakeup_tx_wait(lnk);
544
545	smc_wr_tx_wait_no_pending_sends(lnk);
546	wait_event(lnk->wr_reg_wait, (!atomic_read(&lnk->wr_reg_refcnt)));
547	wait_event(lnk->wr_tx_wait, (!atomic_read(&lnk->wr_tx_refcnt)));
548
549	if (lnk->wr_rx_dma_addr) {
550		ib_dma_unmap_single(ibdev, lnk->wr_rx_dma_addr,
551				    SMC_WR_BUF_SIZE * lnk->wr_rx_cnt,
552				    DMA_FROM_DEVICE);
553		lnk->wr_rx_dma_addr = 0;
554	}
555	if (lnk->wr_tx_dma_addr) {
556		ib_dma_unmap_single(ibdev, lnk->wr_tx_dma_addr,
557				    SMC_WR_BUF_SIZE * lnk->wr_tx_cnt,
558				    DMA_TO_DEVICE);
559		lnk->wr_tx_dma_addr = 0;
560	}
561}
562
563void smc_wr_free_link_mem(struct smc_link *lnk)
564{
565	kfree(lnk->wr_tx_compl);
566	lnk->wr_tx_compl = NULL;
567	kfree(lnk->wr_tx_pends);
568	lnk->wr_tx_pends = NULL;
569	kfree(lnk->wr_tx_mask);
570	lnk->wr_tx_mask = NULL;
571	kfree(lnk->wr_tx_sges);
572	lnk->wr_tx_sges = NULL;
573	kfree(lnk->wr_tx_rdma_sges);
574	lnk->wr_tx_rdma_sges = NULL;
575	kfree(lnk->wr_rx_sges);
576	lnk->wr_rx_sges = NULL;
577	kfree(lnk->wr_tx_rdmas);
578	lnk->wr_tx_rdmas = NULL;
579	kfree(lnk->wr_rx_ibs);
580	lnk->wr_rx_ibs = NULL;
581	kfree(lnk->wr_tx_ibs);
582	lnk->wr_tx_ibs = NULL;
583	kfree(lnk->wr_tx_bufs);
584	lnk->wr_tx_bufs = NULL;
585	kfree(lnk->wr_rx_bufs);
586	lnk->wr_rx_bufs = NULL;
587}
588
589int smc_wr_alloc_link_mem(struct smc_link *link)
590{
591	/* allocate link related memory */
592	link->wr_tx_bufs = kcalloc(SMC_WR_BUF_CNT, SMC_WR_BUF_SIZE, GFP_KERNEL);
593	if (!link->wr_tx_bufs)
594		goto no_mem;
595	link->wr_rx_bufs = kcalloc(SMC_WR_BUF_CNT * 3, SMC_WR_BUF_SIZE,
596				   GFP_KERNEL);
597	if (!link->wr_rx_bufs)
598		goto no_mem_wr_tx_bufs;
599	link->wr_tx_ibs = kcalloc(SMC_WR_BUF_CNT, sizeof(link->wr_tx_ibs[0]),
600				  GFP_KERNEL);
601	if (!link->wr_tx_ibs)
602		goto no_mem_wr_rx_bufs;
603	link->wr_rx_ibs = kcalloc(SMC_WR_BUF_CNT * 3,
604				  sizeof(link->wr_rx_ibs[0]),
605				  GFP_KERNEL);
606	if (!link->wr_rx_ibs)
607		goto no_mem_wr_tx_ibs;
608	link->wr_tx_rdmas = kcalloc(SMC_WR_BUF_CNT,
609				    sizeof(link->wr_tx_rdmas[0]),
610				    GFP_KERNEL);
611	if (!link->wr_tx_rdmas)
612		goto no_mem_wr_rx_ibs;
613	link->wr_tx_rdma_sges = kcalloc(SMC_WR_BUF_CNT,
614					sizeof(link->wr_tx_rdma_sges[0]),
615					GFP_KERNEL);
616	if (!link->wr_tx_rdma_sges)
617		goto no_mem_wr_tx_rdmas;
618	link->wr_tx_sges = kcalloc(SMC_WR_BUF_CNT, sizeof(link->wr_tx_sges[0]),
619				   GFP_KERNEL);
620	if (!link->wr_tx_sges)
621		goto no_mem_wr_tx_rdma_sges;
622	link->wr_rx_sges = kcalloc(SMC_WR_BUF_CNT * 3,
623				   sizeof(link->wr_rx_sges[0]),
624				   GFP_KERNEL);
625	if (!link->wr_rx_sges)
626		goto no_mem_wr_tx_sges;
627	link->wr_tx_mask = kcalloc(BITS_TO_LONGS(SMC_WR_BUF_CNT),
628				   sizeof(*link->wr_tx_mask),
629				   GFP_KERNEL);
630	if (!link->wr_tx_mask)
631		goto no_mem_wr_rx_sges;
632	link->wr_tx_pends = kcalloc(SMC_WR_BUF_CNT,
633				    sizeof(link->wr_tx_pends[0]),
634				    GFP_KERNEL);
635	if (!link->wr_tx_pends)
636		goto no_mem_wr_tx_mask;
637	link->wr_tx_compl = kcalloc(SMC_WR_BUF_CNT,
638				    sizeof(link->wr_tx_compl[0]),
639				    GFP_KERNEL);
640	if (!link->wr_tx_compl)
641		goto no_mem_wr_tx_pends;
642	return 0;
643
644no_mem_wr_tx_pends:
645	kfree(link->wr_tx_pends);
646no_mem_wr_tx_mask:
647	kfree(link->wr_tx_mask);
648no_mem_wr_rx_sges:
649	kfree(link->wr_rx_sges);
650no_mem_wr_tx_sges:
651	kfree(link->wr_tx_sges);
652no_mem_wr_tx_rdma_sges:
653	kfree(link->wr_tx_rdma_sges);
654no_mem_wr_tx_rdmas:
655	kfree(link->wr_tx_rdmas);
656no_mem_wr_rx_ibs:
657	kfree(link->wr_rx_ibs);
658no_mem_wr_tx_ibs:
659	kfree(link->wr_tx_ibs);
660no_mem_wr_rx_bufs:
661	kfree(link->wr_rx_bufs);
662no_mem_wr_tx_bufs:
663	kfree(link->wr_tx_bufs);
664no_mem:
665	return -ENOMEM;
666}
667
668void smc_wr_remove_dev(struct smc_ib_device *smcibdev)
669{
670	tasklet_kill(&smcibdev->recv_tasklet);
671	tasklet_kill(&smcibdev->send_tasklet);
672}
673
674void smc_wr_add_dev(struct smc_ib_device *smcibdev)
675{
676	tasklet_init(&smcibdev->recv_tasklet, smc_wr_rx_tasklet_fn,
677		     (unsigned long)smcibdev);
678	tasklet_init(&smcibdev->send_tasklet, smc_wr_tx_tasklet_fn,
679		     (unsigned long)smcibdev);
680}
681
682int smc_wr_create_link(struct smc_link *lnk)
683{
684	struct ib_device *ibdev = lnk->smcibdev->ibdev;
685	int rc = 0;
686
687	smc_wr_tx_set_wr_id(&lnk->wr_tx_id, 0);
688	lnk->wr_rx_id = 0;
689	lnk->wr_rx_dma_addr = ib_dma_map_single(
690		ibdev, lnk->wr_rx_bufs,	SMC_WR_BUF_SIZE * lnk->wr_rx_cnt,
691		DMA_FROM_DEVICE);
692	if (ib_dma_mapping_error(ibdev, lnk->wr_rx_dma_addr)) {
693		lnk->wr_rx_dma_addr = 0;
694		rc = -EIO;
695		goto out;
696	}
697	lnk->wr_tx_dma_addr = ib_dma_map_single(
698		ibdev, lnk->wr_tx_bufs,	SMC_WR_BUF_SIZE * lnk->wr_tx_cnt,
699		DMA_TO_DEVICE);
700	if (ib_dma_mapping_error(ibdev, lnk->wr_tx_dma_addr)) {
701		rc = -EIO;
702		goto dma_unmap;
703	}
704	smc_wr_init_sge(lnk);
705	memset(lnk->wr_tx_mask, 0,
706	       BITS_TO_LONGS(SMC_WR_BUF_CNT) * sizeof(*lnk->wr_tx_mask));
707	init_waitqueue_head(&lnk->wr_tx_wait);
708	atomic_set(&lnk->wr_tx_refcnt, 0);
709	init_waitqueue_head(&lnk->wr_reg_wait);
710	atomic_set(&lnk->wr_reg_refcnt, 0);
711	return rc;
712
713dma_unmap:
714	ib_dma_unmap_single(ibdev, lnk->wr_rx_dma_addr,
715			    SMC_WR_BUF_SIZE * lnk->wr_rx_cnt,
716			    DMA_FROM_DEVICE);
717	lnk->wr_rx_dma_addr = 0;
718out:
719	return rc;
720}
721