1 // SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
2
3 /* Authors: Bernard Metzler <bmt@zurich.ibm.com> */
4 /* Copyright (c) 2008-2019, IBM Corporation */
5
6 #include <linux/errno.h>
7 #include <linux/types.h>
8 #include <linux/net.h>
9 #include <linux/scatterlist.h>
10 #include <linux/highmem.h>
11 #include <net/tcp.h>
12
13 #include <rdma/iw_cm.h>
14 #include <rdma/ib_verbs.h>
15 #include <rdma/ib_user_verbs.h>
16
17 #include "siw.h"
18 #include "siw_verbs.h"
19 #include "siw_mem.h"
20
21 #define MAX_HDR_INLINE \
22 (((uint32_t)(sizeof(struct siw_rreq_pkt) - \
23 sizeof(struct iwarp_send))) & 0xF8)
24
siw_get_pblpage(struct siw_mem * mem,u64 addr,int * idx)25 static struct page *siw_get_pblpage(struct siw_mem *mem, u64 addr, int *idx)
26 {
27 struct siw_pbl *pbl = mem->pbl;
28 u64 offset = addr - mem->va;
29 dma_addr_t paddr = siw_pbl_get_buffer(pbl, offset, NULL, idx);
30
31 if (paddr)
32 return ib_virt_dma_to_page(paddr);
33
34 return NULL;
35 }
36
siw_get_page(struct siw_mem * mem,struct siw_sge * sge,unsigned long offset,int * pbl_idx)37 static struct page *siw_get_page(struct siw_mem *mem, struct siw_sge *sge,
38 unsigned long offset, int *pbl_idx)
39 {
40 if (!mem->is_pbl)
41 return siw_get_upage(mem->umem, sge->laddr + offset);
42 else
43 return siw_get_pblpage(mem, sge->laddr + offset, pbl_idx);
44 }
45
46 /*
47 * Copy short payload at provided destination payload address
48 */
siw_try_1seg(struct siw_iwarp_tx * c_tx,void * paddr)49 static int siw_try_1seg(struct siw_iwarp_tx *c_tx, void *paddr)
50 {
51 struct siw_wqe *wqe = &c_tx->wqe_active;
52 struct siw_sge *sge = &wqe->sqe.sge[0];
53 u32 bytes = sge->length;
54
55 if (bytes > MAX_HDR_INLINE || wqe->sqe.num_sge != 1)
56 return MAX_HDR_INLINE + 1;
57
58 if (!bytes)
59 return 0;
60
61 if (tx_flags(wqe) & SIW_WQE_INLINE) {
62 memcpy(paddr, &wqe->sqe.sge[1], bytes);
63 } else {
64 struct siw_mem *mem = wqe->mem[0];
65
66 if (!mem->mem_obj) {
67 /* Kernel client using kva */
68 memcpy(paddr, ib_virt_dma_to_ptr(sge->laddr), bytes);
69 } else if (c_tx->in_syscall) {
70 if (copy_from_user(paddr, u64_to_user_ptr(sge->laddr),
71 bytes))
72 return -EFAULT;
73 } else {
74 unsigned int off = sge->laddr & ~PAGE_MASK;
75 struct page *p;
76 char *buffer;
77 int pbl_idx = 0;
78
79 p = siw_get_page(mem, sge, 0, &pbl_idx);
80 if (unlikely(!p))
81 return -EFAULT;
82
83 buffer = kmap_local_page(p);
84
85 if (likely(PAGE_SIZE - off >= bytes)) {
86 memcpy(paddr, buffer + off, bytes);
87 } else {
88 unsigned long part = bytes - (PAGE_SIZE - off);
89
90 memcpy(paddr, buffer + off, part);
91 kunmap_local(buffer);
92
93 p = siw_get_page(mem, sge, part, &pbl_idx);
94 if (unlikely(!p))
95 return -EFAULT;
96
97 buffer = kmap_local_page(p);
98 memcpy(paddr + part, buffer, bytes - part);
99 }
100 kunmap_local(buffer);
101 }
102 }
103 return (int)bytes;
104 }
105
106 #define PKT_FRAGMENTED 1
107 #define PKT_COMPLETE 0
108
109 /*
110 * siw_qp_prepare_tx()
111 *
112 * Prepare tx state for sending out one fpdu. Builds complete pkt
113 * if no user data or only immediate data are present.
114 *
115 * returns PKT_COMPLETE if complete pkt built, PKT_FRAGMENTED otherwise.
116 */
siw_qp_prepare_tx(struct siw_iwarp_tx * c_tx)117 static int siw_qp_prepare_tx(struct siw_iwarp_tx *c_tx)
118 {
119 struct siw_wqe *wqe = &c_tx->wqe_active;
120 char *crc = NULL;
121 int data = 0;
122
123 switch (tx_type(wqe)) {
124 case SIW_OP_READ:
125 case SIW_OP_READ_LOCAL_INV:
126 memcpy(&c_tx->pkt.ctrl,
127 &iwarp_pktinfo[RDMAP_RDMA_READ_REQ].ctrl,
128 sizeof(struct iwarp_ctrl));
129
130 c_tx->pkt.rreq.rsvd = 0;
131 c_tx->pkt.rreq.ddp_qn = htonl(RDMAP_UNTAGGED_QN_RDMA_READ);
132 c_tx->pkt.rreq.ddp_msn =
133 htonl(++c_tx->ddp_msn[RDMAP_UNTAGGED_QN_RDMA_READ]);
134 c_tx->pkt.rreq.ddp_mo = 0;
135 c_tx->pkt.rreq.sink_stag = htonl(wqe->sqe.sge[0].lkey);
136 c_tx->pkt.rreq.sink_to =
137 cpu_to_be64(wqe->sqe.sge[0].laddr);
138 c_tx->pkt.rreq.source_stag = htonl(wqe->sqe.rkey);
139 c_tx->pkt.rreq.source_to = cpu_to_be64(wqe->sqe.raddr);
140 c_tx->pkt.rreq.read_size = htonl(wqe->sqe.sge[0].length);
141
142 c_tx->ctrl_len = sizeof(struct iwarp_rdma_rreq);
143 crc = (char *)&c_tx->pkt.rreq_pkt.crc;
144 break;
145
146 case SIW_OP_SEND:
147 if (tx_flags(wqe) & SIW_WQE_SOLICITED)
148 memcpy(&c_tx->pkt.ctrl,
149 &iwarp_pktinfo[RDMAP_SEND_SE].ctrl,
150 sizeof(struct iwarp_ctrl));
151 else
152 memcpy(&c_tx->pkt.ctrl, &iwarp_pktinfo[RDMAP_SEND].ctrl,
153 sizeof(struct iwarp_ctrl));
154
155 c_tx->pkt.send.ddp_qn = RDMAP_UNTAGGED_QN_SEND;
156 c_tx->pkt.send.ddp_msn =
157 htonl(++c_tx->ddp_msn[RDMAP_UNTAGGED_QN_SEND]);
158 c_tx->pkt.send.ddp_mo = 0;
159
160 c_tx->pkt.send_inv.inval_stag = 0;
161
162 c_tx->ctrl_len = sizeof(struct iwarp_send);
163
164 crc = (char *)&c_tx->pkt.send_pkt.crc;
165 data = siw_try_1seg(c_tx, crc);
166 break;
167
168 case SIW_OP_SEND_REMOTE_INV:
169 if (tx_flags(wqe) & SIW_WQE_SOLICITED)
170 memcpy(&c_tx->pkt.ctrl,
171 &iwarp_pktinfo[RDMAP_SEND_SE_INVAL].ctrl,
172 sizeof(struct iwarp_ctrl));
173 else
174 memcpy(&c_tx->pkt.ctrl,
175 &iwarp_pktinfo[RDMAP_SEND_INVAL].ctrl,
176 sizeof(struct iwarp_ctrl));
177
178 c_tx->pkt.send.ddp_qn = RDMAP_UNTAGGED_QN_SEND;
179 c_tx->pkt.send.ddp_msn =
180 htonl(++c_tx->ddp_msn[RDMAP_UNTAGGED_QN_SEND]);
181 c_tx->pkt.send.ddp_mo = 0;
182
183 c_tx->pkt.send_inv.inval_stag = cpu_to_be32(wqe->sqe.rkey);
184
185 c_tx->ctrl_len = sizeof(struct iwarp_send_inv);
186
187 crc = (char *)&c_tx->pkt.send_pkt.crc;
188 data = siw_try_1seg(c_tx, crc);
189 break;
190
191 case SIW_OP_WRITE:
192 memcpy(&c_tx->pkt.ctrl, &iwarp_pktinfo[RDMAP_RDMA_WRITE].ctrl,
193 sizeof(struct iwarp_ctrl));
194
195 c_tx->pkt.rwrite.sink_stag = htonl(wqe->sqe.rkey);
196 c_tx->pkt.rwrite.sink_to = cpu_to_be64(wqe->sqe.raddr);
197 c_tx->ctrl_len = sizeof(struct iwarp_rdma_write);
198
199 crc = (char *)&c_tx->pkt.write_pkt.crc;
200 data = siw_try_1seg(c_tx, crc);
201 break;
202
203 case SIW_OP_READ_RESPONSE:
204 memcpy(&c_tx->pkt.ctrl,
205 &iwarp_pktinfo[RDMAP_RDMA_READ_RESP].ctrl,
206 sizeof(struct iwarp_ctrl));
207
208 /* NBO */
209 c_tx->pkt.rresp.sink_stag = cpu_to_be32(wqe->sqe.rkey);
210 c_tx->pkt.rresp.sink_to = cpu_to_be64(wqe->sqe.raddr);
211
212 c_tx->ctrl_len = sizeof(struct iwarp_rdma_rresp);
213
214 crc = (char *)&c_tx->pkt.write_pkt.crc;
215 data = siw_try_1seg(c_tx, crc);
216 break;
217
218 default:
219 siw_dbg_qp(tx_qp(c_tx), "stale wqe type %d\n", tx_type(wqe));
220 return -EOPNOTSUPP;
221 }
222 if (unlikely(data < 0))
223 return data;
224
225 c_tx->ctrl_sent = 0;
226
227 if (data <= MAX_HDR_INLINE) {
228 if (data) {
229 wqe->processed = data;
230
231 c_tx->pkt.ctrl.mpa_len =
232 htons(c_tx->ctrl_len + data - MPA_HDR_SIZE);
233
234 /* Add pad, if needed */
235 data += -(int)data & 0x3;
236 /* advance CRC location after payload */
237 crc += data;
238 c_tx->ctrl_len += data;
239
240 if (!(c_tx->pkt.ctrl.ddp_rdmap_ctrl & DDP_FLAG_TAGGED))
241 c_tx->pkt.c_untagged.ddp_mo = 0;
242 else
243 c_tx->pkt.c_tagged.ddp_to =
244 cpu_to_be64(wqe->sqe.raddr);
245 }
246
247 *(u32 *)crc = 0;
248 /*
249 * Do complete CRC if enabled and short packet
250 */
251 if (c_tx->mpa_crc_enabled)
252 siw_crc_oneshot(&c_tx->pkt, c_tx->ctrl_len, (u8 *)crc);
253 c_tx->ctrl_len += MPA_CRC_SIZE;
254
255 return PKT_COMPLETE;
256 }
257 c_tx->ctrl_len += MPA_CRC_SIZE;
258 c_tx->sge_idx = 0;
259 c_tx->sge_off = 0;
260 c_tx->pbl_idx = 0;
261
262 /*
263 * Allow direct sending out of user buffer if WR is non signalled
264 * and payload is over threshold.
265 * Per RDMA verbs, the application should not change the send buffer
266 * until the work completed. In iWarp, work completion is only
267 * local delivery to TCP. TCP may reuse the buffer for
268 * retransmission. Changing unsent data also breaks the CRC,
269 * if applied.
270 */
271 if (c_tx->zcopy_tx && wqe->bytes >= SENDPAGE_THRESH &&
272 !(tx_flags(wqe) & SIW_WQE_SIGNALLED))
273 c_tx->use_sendpage = 1;
274 else
275 c_tx->use_sendpage = 0;
276
277 return PKT_FRAGMENTED;
278 }
279
280 /*
281 * Send out one complete control type FPDU, or header of FPDU carrying
282 * data. Used for fixed sized packets like Read.Requests or zero length
283 * SENDs, WRITEs, READ.Responses, or header only.
284 */
siw_tx_ctrl(struct siw_iwarp_tx * c_tx,struct socket * s,int flags)285 static int siw_tx_ctrl(struct siw_iwarp_tx *c_tx, struct socket *s,
286 int flags)
287 {
288 struct msghdr msg = { .msg_flags = flags };
289 struct kvec iov = { .iov_base =
290 (char *)&c_tx->pkt.ctrl + c_tx->ctrl_sent,
291 .iov_len = c_tx->ctrl_len - c_tx->ctrl_sent };
292
293 int rv = kernel_sendmsg(s, &msg, &iov, 1, iov.iov_len);
294
295 if (rv >= 0) {
296 c_tx->ctrl_sent += rv;
297
298 if (c_tx->ctrl_sent == c_tx->ctrl_len)
299 rv = 0;
300 else
301 rv = -EAGAIN;
302 }
303 return rv;
304 }
305
306 /*
307 * 0copy TCP transmit interface: Use MSG_SPLICE_PAGES.
308 *
309 * Using sendpage to push page by page appears to be less efficient
310 * than using sendmsg, even if data are copied.
311 *
312 * A general performance limitation might be the extra four bytes
313 * trailer checksum segment to be pushed after user data.
314 */
siw_tcp_sendpages(struct socket * s,struct page ** page,int offset,size_t size)315 static int siw_tcp_sendpages(struct socket *s, struct page **page, int offset,
316 size_t size)
317 {
318 struct bio_vec bvec;
319 struct msghdr msg = {
320 .msg_flags = (MSG_MORE | MSG_DONTWAIT | MSG_SPLICE_PAGES),
321 };
322 struct sock *sk = s->sk;
323 int i = 0, rv = 0, sent = 0;
324
325 while (size) {
326 size_t bytes = min_t(size_t, PAGE_SIZE - offset, size);
327
328 if (size + offset <= PAGE_SIZE)
329 msg.msg_flags &= ~MSG_MORE;
330
331 tcp_rate_check_app_limited(sk);
332 if (!sendpage_ok(page[i]))
333 msg.msg_flags &= ~MSG_SPLICE_PAGES;
334 bvec_set_page(&bvec, page[i], bytes, offset);
335 iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, &bvec, 1, size);
336
337 try_page_again:
338 lock_sock(sk);
339 rv = tcp_sendmsg_locked(sk, &msg, size);
340 release_sock(sk);
341
342 if (rv > 0) {
343 size -= rv;
344 sent += rv;
345 if (rv != bytes) {
346 offset += rv;
347 bytes -= rv;
348 goto try_page_again;
349 }
350 offset = 0;
351 } else {
352 if (rv == -EAGAIN || rv == 0)
353 break;
354 return rv;
355 }
356 i++;
357 }
358 return sent;
359 }
360
361 /*
362 * siw_0copy_tx()
363 *
364 * Pushes list of pages to TCP socket. If pages from multiple
365 * SGE's, all referenced pages of each SGE are pushed in one
366 * shot.
367 */
siw_0copy_tx(struct socket * s,struct page ** page,struct siw_sge * sge,unsigned int offset,unsigned int size)368 static int siw_0copy_tx(struct socket *s, struct page **page,
369 struct siw_sge *sge, unsigned int offset,
370 unsigned int size)
371 {
372 int i = 0, sent = 0, rv;
373 int sge_bytes = min(sge->length - offset, size);
374
375 offset = (sge->laddr + offset) & ~PAGE_MASK;
376
377 while (sent != size) {
378 rv = siw_tcp_sendpages(s, &page[i], offset, sge_bytes);
379 if (rv >= 0) {
380 sent += rv;
381 if (size == sent || sge_bytes > rv)
382 break;
383
384 i += PAGE_ALIGN(sge_bytes + offset) >> PAGE_SHIFT;
385 sge++;
386 sge_bytes = min(sge->length, size - sent);
387 offset = sge->laddr & ~PAGE_MASK;
388 } else {
389 sent = rv;
390 break;
391 }
392 }
393 return sent;
394 }
395
396 #define MAX_TRAILER (MPA_CRC_SIZE + 4)
397
siw_unmap_pages(struct kvec * iov,unsigned long kmap_mask,int len)398 static void siw_unmap_pages(struct kvec *iov, unsigned long kmap_mask, int len)
399 {
400 int i;
401
402 /*
403 * Work backwards through the array to honor the kmap_local_page()
404 * ordering requirements.
405 */
406 for (i = (len-1); i >= 0; i--) {
407 if (kmap_mask & BIT(i)) {
408 unsigned long addr = (unsigned long)iov[i].iov_base;
409
410 kunmap_local((void *)(addr & PAGE_MASK));
411 }
412 }
413 }
414
415 /*
416 * siw_tx_hdt() tries to push a complete packet to TCP where all
417 * packet fragments are referenced by the elements of one iovec.
418 * For the data portion, each involved page must be referenced by
419 * one extra element. All sge's data can be non-aligned to page
420 * boundaries. Two more elements are referencing iWARP header
421 * and trailer:
422 * MAX_ARRAY = 64KB/PAGE_SIZE + 1 + (2 * (SIW_MAX_SGE - 1) + HDR + TRL
423 */
424 #define MAX_ARRAY ((0xffff / PAGE_SIZE) + 1 + (2 * (SIW_MAX_SGE - 1) + 2))
425
426 /*
427 * Write out iov referencing hdr, data and trailer of current FPDU.
428 * Update transmit state dependent on write return status
429 */
siw_tx_hdt(struct siw_iwarp_tx * c_tx,struct socket * s)430 static int siw_tx_hdt(struct siw_iwarp_tx *c_tx, struct socket *s)
431 {
432 struct siw_wqe *wqe = &c_tx->wqe_active;
433 struct siw_sge *sge = &wqe->sqe.sge[c_tx->sge_idx];
434 struct kvec iov[MAX_ARRAY];
435 struct page *page_array[MAX_ARRAY];
436 struct msghdr msg = { .msg_flags = MSG_DONTWAIT | MSG_EOR };
437
438 int seg = 0, do_crc = c_tx->do_crc, is_kva = 0, rv;
439 unsigned int data_len = c_tx->bytes_unsent, hdr_len = 0, trl_len = 0,
440 sge_off = c_tx->sge_off, sge_idx = c_tx->sge_idx,
441 pbl_idx = c_tx->pbl_idx;
442 unsigned long kmap_mask = 0L;
443
444 if (c_tx->state == SIW_SEND_HDR) {
445 if (c_tx->use_sendpage) {
446 rv = siw_tx_ctrl(c_tx, s, MSG_DONTWAIT | MSG_MORE);
447 if (rv)
448 goto done;
449
450 c_tx->state = SIW_SEND_DATA;
451 } else {
452 iov[0].iov_base =
453 (char *)&c_tx->pkt.ctrl + c_tx->ctrl_sent;
454 iov[0].iov_len = hdr_len =
455 c_tx->ctrl_len - c_tx->ctrl_sent;
456 seg = 1;
457 }
458 }
459
460 wqe->processed += data_len;
461
462 while (data_len) { /* walk the list of SGE's */
463 unsigned int sge_len = min(sge->length - sge_off, data_len);
464 unsigned int fp_off = (sge->laddr + sge_off) & ~PAGE_MASK;
465 struct siw_mem *mem;
466
467 if (!(tx_flags(wqe) & SIW_WQE_INLINE)) {
468 mem = wqe->mem[sge_idx];
469 is_kva = mem->mem_obj == NULL ? 1 : 0;
470 } else {
471 is_kva = 1;
472 }
473 if (is_kva && !c_tx->use_sendpage) {
474 /*
475 * tx from kernel virtual address: either inline data
476 * or memory region with assigned kernel buffer
477 */
478 iov[seg].iov_base =
479 ib_virt_dma_to_ptr(sge->laddr + sge_off);
480 iov[seg].iov_len = sge_len;
481
482 if (do_crc)
483 siw_crc_update(&c_tx->mpa_crc,
484 iov[seg].iov_base, sge_len);
485 sge_off += sge_len;
486 data_len -= sge_len;
487 seg++;
488 goto sge_done;
489 }
490
491 while (sge_len) {
492 size_t plen = min((int)PAGE_SIZE - fp_off, sge_len);
493 void *kaddr;
494
495 if (!is_kva) {
496 struct page *p;
497
498 p = siw_get_page(mem, sge, sge_off, &pbl_idx);
499 if (unlikely(!p)) {
500 siw_unmap_pages(iov, kmap_mask, seg);
501 wqe->processed -= c_tx->bytes_unsent;
502 rv = -EFAULT;
503 goto done_crc;
504 }
505 page_array[seg] = p;
506
507 if (!c_tx->use_sendpage) {
508 void *kaddr = kmap_local_page(p);
509
510 /* Remember for later kunmap() */
511 kmap_mask |= BIT(seg);
512 iov[seg].iov_base = kaddr + fp_off;
513 iov[seg].iov_len = plen;
514
515 if (do_crc)
516 siw_crc_update(
517 &c_tx->mpa_crc,
518 iov[seg].iov_base,
519 plen);
520 } else if (do_crc) {
521 kaddr = kmap_local_page(p);
522 siw_crc_update(&c_tx->mpa_crc,
523 kaddr + fp_off, plen);
524 kunmap_local(kaddr);
525 }
526 } else {
527 /*
528 * Cast to an uintptr_t to preserve all 64 bits
529 * in sge->laddr.
530 */
531 u64 va = sge->laddr + sge_off;
532
533 page_array[seg] = ib_virt_dma_to_page(va);
534 if (do_crc)
535 siw_crc_update(&c_tx->mpa_crc,
536 ib_virt_dma_to_ptr(va),
537 plen);
538 }
539
540 sge_len -= plen;
541 sge_off += plen;
542 data_len -= plen;
543 fp_off = 0;
544
545 if (++seg >= (int)MAX_ARRAY) {
546 siw_dbg_qp(tx_qp(c_tx), "to many fragments\n");
547 siw_unmap_pages(iov, kmap_mask, seg-1);
548 wqe->processed -= c_tx->bytes_unsent;
549 rv = -EMSGSIZE;
550 goto done_crc;
551 }
552 }
553 sge_done:
554 /* Update SGE variables at end of SGE */
555 if (sge_off == sge->length &&
556 (data_len != 0 || wqe->processed < wqe->bytes)) {
557 sge_idx++;
558 sge++;
559 sge_off = 0;
560 }
561 }
562 /* trailer */
563 if (likely(c_tx->state != SIW_SEND_TRAILER)) {
564 iov[seg].iov_base = &c_tx->trailer.pad[4 - c_tx->pad];
565 iov[seg].iov_len = trl_len = MAX_TRAILER - (4 - c_tx->pad);
566 } else {
567 iov[seg].iov_base = &c_tx->trailer.pad[c_tx->ctrl_sent];
568 iov[seg].iov_len = trl_len = MAX_TRAILER - c_tx->ctrl_sent;
569 }
570
571 if (c_tx->pad) {
572 *(u32 *)c_tx->trailer.pad = 0;
573 if (do_crc)
574 siw_crc_update(&c_tx->mpa_crc,
575 (u8 *)&c_tx->trailer.crc - c_tx->pad,
576 c_tx->pad);
577 }
578 if (!c_tx->mpa_crc_enabled)
579 c_tx->trailer.crc = 0;
580 else if (do_crc)
581 siw_crc_final(&c_tx->mpa_crc, (u8 *)&c_tx->trailer.crc);
582
583 data_len = c_tx->bytes_unsent;
584
585 if (c_tx->use_sendpage) {
586 rv = siw_0copy_tx(s, page_array, &wqe->sqe.sge[c_tx->sge_idx],
587 c_tx->sge_off, data_len);
588 if (rv == data_len) {
589 rv = kernel_sendmsg(s, &msg, &iov[seg], 1, trl_len);
590 if (rv > 0)
591 rv += data_len;
592 else
593 rv = data_len;
594 }
595 } else {
596 rv = kernel_sendmsg(s, &msg, iov, seg + 1,
597 hdr_len + data_len + trl_len);
598 siw_unmap_pages(iov, kmap_mask, seg);
599 }
600 if (rv < (int)hdr_len) {
601 /* Not even complete hdr pushed or negative rv */
602 wqe->processed -= data_len;
603 if (rv >= 0) {
604 c_tx->ctrl_sent += rv;
605 rv = -EAGAIN;
606 }
607 goto done_crc;
608 }
609 rv -= hdr_len;
610
611 if (rv >= (int)data_len) {
612 /* all user data pushed to TCP or no data to push */
613 if (data_len > 0 && wqe->processed < wqe->bytes) {
614 /* Save the current state for next tx */
615 c_tx->sge_idx = sge_idx;
616 c_tx->sge_off = sge_off;
617 c_tx->pbl_idx = pbl_idx;
618 }
619 rv -= data_len;
620
621 if (rv == trl_len) /* all pushed */
622 rv = 0;
623 else {
624 c_tx->state = SIW_SEND_TRAILER;
625 c_tx->ctrl_len = MAX_TRAILER;
626 c_tx->ctrl_sent = rv + 4 - c_tx->pad;
627 c_tx->bytes_unsent = 0;
628 rv = -EAGAIN;
629 }
630
631 } else if (data_len > 0) {
632 /* Maybe some user data pushed to TCP */
633 c_tx->state = SIW_SEND_DATA;
634 wqe->processed -= data_len - rv;
635
636 if (rv) {
637 /*
638 * Some bytes out. Recompute tx state based
639 * on old state and bytes pushed
640 */
641 unsigned int sge_unsent;
642
643 c_tx->bytes_unsent -= rv;
644 sge = &wqe->sqe.sge[c_tx->sge_idx];
645 sge_unsent = sge->length - c_tx->sge_off;
646
647 while (sge_unsent <= rv) {
648 rv -= sge_unsent;
649 c_tx->sge_idx++;
650 c_tx->sge_off = 0;
651 sge++;
652 sge_unsent = sge->length;
653 }
654 c_tx->sge_off += rv;
655 }
656 rv = -EAGAIN;
657 }
658 done_crc:
659 c_tx->do_crc = 0;
660 done:
661 return rv;
662 }
663
siw_update_tcpseg(struct siw_iwarp_tx * c_tx,struct socket * s)664 static void siw_update_tcpseg(struct siw_iwarp_tx *c_tx,
665 struct socket *s)
666 {
667 struct tcp_sock *tp = tcp_sk(s->sk);
668
669 if (tp->gso_segs) {
670 if (c_tx->gso_seg_limit == 0)
671 c_tx->tcp_seglen = tp->mss_cache * tp->gso_segs;
672 else
673 c_tx->tcp_seglen =
674 tp->mss_cache *
675 min_t(u16, c_tx->gso_seg_limit, tp->gso_segs);
676 } else {
677 c_tx->tcp_seglen = tp->mss_cache;
678 }
679 /* Loopback may give odd numbers */
680 c_tx->tcp_seglen &= 0xfffffff8;
681 }
682
683 /*
684 * siw_prepare_fpdu()
685 *
686 * Prepares transmit context to send out one FPDU if FPDU will contain
687 * user data and user data are not immediate data.
688 * Computes maximum FPDU length to fill up TCP MSS if possible.
689 *
690 * @qp: QP from which to transmit
691 * @wqe: Current WQE causing transmission
692 *
693 * TODO: Take into account real available sendspace on socket
694 * to avoid header misalignment due to send pausing within
695 * fpdu transmission
696 */
siw_prepare_fpdu(struct siw_qp * qp,struct siw_wqe * wqe)697 static void siw_prepare_fpdu(struct siw_qp *qp, struct siw_wqe *wqe)
698 {
699 struct siw_iwarp_tx *c_tx = &qp->tx_ctx;
700 int data_len;
701
702 c_tx->ctrl_len =
703 iwarp_pktinfo[__rdmap_get_opcode(&c_tx->pkt.ctrl)].hdr_len;
704 c_tx->ctrl_sent = 0;
705
706 /*
707 * Update target buffer offset if any
708 */
709 if (!(c_tx->pkt.ctrl.ddp_rdmap_ctrl & DDP_FLAG_TAGGED))
710 /* Untagged message */
711 c_tx->pkt.c_untagged.ddp_mo = cpu_to_be32(wqe->processed);
712 else /* Tagged message */
713 c_tx->pkt.c_tagged.ddp_to =
714 cpu_to_be64(wqe->sqe.raddr + wqe->processed);
715
716 data_len = wqe->bytes - wqe->processed;
717 if (data_len + c_tx->ctrl_len + MPA_CRC_SIZE > c_tx->tcp_seglen) {
718 /* Trim DDP payload to fit into current TCP segment */
719 data_len = c_tx->tcp_seglen - (c_tx->ctrl_len + MPA_CRC_SIZE);
720 c_tx->pkt.ctrl.ddp_rdmap_ctrl &= ~DDP_FLAG_LAST;
721 c_tx->pad = 0;
722 } else {
723 c_tx->pkt.ctrl.ddp_rdmap_ctrl |= DDP_FLAG_LAST;
724 c_tx->pad = -data_len & 0x3;
725 }
726 c_tx->bytes_unsent = data_len;
727
728 c_tx->pkt.ctrl.mpa_len =
729 htons(c_tx->ctrl_len + data_len - MPA_HDR_SIZE);
730
731 /*
732 * Init MPA CRC computation
733 */
734 if (c_tx->mpa_crc_enabled) {
735 siw_crc_init(&c_tx->mpa_crc);
736 siw_crc_update(&c_tx->mpa_crc, &c_tx->pkt, c_tx->ctrl_len);
737 c_tx->do_crc = 1;
738 }
739 }
740
741 /*
742 * siw_check_sgl_tx()
743 *
744 * Check permissions for a list of SGE's (SGL).
745 * A successful check will have all memory referenced
746 * for transmission resolved and assigned to the WQE.
747 *
748 * @pd: Protection Domain SGL should belong to
749 * @wqe: WQE to be checked
750 * @perms: requested access permissions
751 *
752 */
753
siw_check_sgl_tx(struct ib_pd * pd,struct siw_wqe * wqe,enum ib_access_flags perms)754 static int siw_check_sgl_tx(struct ib_pd *pd, struct siw_wqe *wqe,
755 enum ib_access_flags perms)
756 {
757 struct siw_sge *sge = &wqe->sqe.sge[0];
758 int i, len, num_sge = wqe->sqe.num_sge;
759
760 if (unlikely(num_sge > SIW_MAX_SGE))
761 return -EINVAL;
762
763 for (i = 0, len = 0; num_sge; num_sge--, i++, sge++) {
764 /*
765 * rdma verbs: do not check stag for a zero length sge
766 */
767 if (sge->length) {
768 int rv = siw_check_sge(pd, sge, &wqe->mem[i], perms, 0,
769 sge->length);
770
771 if (unlikely(rv != E_ACCESS_OK))
772 return rv;
773 }
774 len += sge->length;
775 }
776 return len;
777 }
778
779 /*
780 * siw_qp_sq_proc_tx()
781 *
782 * Process one WQE which needs transmission on the wire.
783 */
siw_qp_sq_proc_tx(struct siw_qp * qp,struct siw_wqe * wqe)784 static int siw_qp_sq_proc_tx(struct siw_qp *qp, struct siw_wqe *wqe)
785 {
786 struct siw_iwarp_tx *c_tx = &qp->tx_ctx;
787 struct socket *s = qp->attrs.sk;
788 int rv = 0, burst_len = qp->tx_ctx.burst;
789 enum rdmap_ecode ecode = RDMAP_ECODE_CATASTROPHIC_STREAM;
790
791 if (unlikely(wqe->wr_status == SIW_WR_IDLE))
792 return 0;
793
794 if (!burst_len)
795 burst_len = SQ_USER_MAXBURST;
796
797 if (wqe->wr_status == SIW_WR_QUEUED) {
798 if (!(wqe->sqe.flags & SIW_WQE_INLINE)) {
799 if (tx_type(wqe) == SIW_OP_READ_RESPONSE)
800 wqe->sqe.num_sge = 1;
801
802 if (tx_type(wqe) != SIW_OP_READ &&
803 tx_type(wqe) != SIW_OP_READ_LOCAL_INV) {
804 /*
805 * Reference memory to be tx'd w/o checking
806 * access for LOCAL_READ permission, since
807 * not defined in RDMA core.
808 */
809 rv = siw_check_sgl_tx(qp->pd, wqe, 0);
810 if (rv < 0) {
811 if (tx_type(wqe) ==
812 SIW_OP_READ_RESPONSE)
813 ecode = siw_rdmap_error(-rv);
814 rv = -EINVAL;
815 goto tx_error;
816 }
817 wqe->bytes = rv;
818 } else {
819 wqe->bytes = 0;
820 }
821 } else {
822 wqe->bytes = wqe->sqe.sge[0].length;
823 if (!rdma_is_kernel_res(&qp->base_qp.res)) {
824 if (wqe->bytes > SIW_MAX_INLINE) {
825 rv = -EINVAL;
826 goto tx_error;
827 }
828 wqe->sqe.sge[0].laddr =
829 (u64)(uintptr_t)&wqe->sqe.sge[1];
830 }
831 }
832 wqe->wr_status = SIW_WR_INPROGRESS;
833 wqe->processed = 0;
834
835 siw_update_tcpseg(c_tx, s);
836
837 rv = siw_qp_prepare_tx(c_tx);
838 if (rv == PKT_FRAGMENTED) {
839 c_tx->state = SIW_SEND_HDR;
840 siw_prepare_fpdu(qp, wqe);
841 } else if (rv == PKT_COMPLETE) {
842 c_tx->state = SIW_SEND_SHORT_FPDU;
843 } else {
844 goto tx_error;
845 }
846 }
847
848 next_segment:
849 siw_dbg_qp(qp, "wr type %d, state %d, data %u, sent %u, id %llx\n",
850 tx_type(wqe), wqe->wr_status, wqe->bytes, wqe->processed,
851 wqe->sqe.id);
852
853 if (--burst_len == 0) {
854 rv = -EINPROGRESS;
855 goto tx_done;
856 }
857 if (c_tx->state == SIW_SEND_SHORT_FPDU) {
858 enum siw_opcode tx_type = tx_type(wqe);
859 unsigned int msg_flags;
860
861 if (siw_sq_empty(qp) || !siw_tcp_nagle || burst_len == 1)
862 /*
863 * End current TCP segment, if SQ runs empty,
864 * or siw_tcp_nagle is not set, or we bail out
865 * soon due to no burst credit left.
866 */
867 msg_flags = MSG_DONTWAIT;
868 else
869 msg_flags = MSG_DONTWAIT | MSG_MORE;
870
871 rv = siw_tx_ctrl(c_tx, s, msg_flags);
872
873 if (!rv && tx_type != SIW_OP_READ &&
874 tx_type != SIW_OP_READ_LOCAL_INV)
875 wqe->processed = wqe->bytes;
876
877 goto tx_done;
878
879 } else {
880 rv = siw_tx_hdt(c_tx, s);
881 }
882 if (!rv) {
883 /*
884 * One segment sent. Processing completed if last
885 * segment, Do next segment otherwise.
886 */
887 if (unlikely(c_tx->tx_suspend)) {
888 /*
889 * Verbs, 6.4.: Try stopping sending after a full
890 * DDP segment if the connection goes down
891 * (== peer halfclose)
892 */
893 rv = -ECONNABORTED;
894 goto tx_done;
895 }
896 if (c_tx->pkt.ctrl.ddp_rdmap_ctrl & DDP_FLAG_LAST) {
897 siw_dbg_qp(qp, "WQE completed\n");
898 goto tx_done;
899 }
900 c_tx->state = SIW_SEND_HDR;
901
902 siw_update_tcpseg(c_tx, s);
903
904 siw_prepare_fpdu(qp, wqe);
905 goto next_segment;
906 }
907 tx_done:
908 qp->tx_ctx.burst = burst_len;
909 return rv;
910
911 tx_error:
912 if (ecode != RDMAP_ECODE_CATASTROPHIC_STREAM)
913 siw_init_terminate(qp, TERM_ERROR_LAYER_RDMAP,
914 RDMAP_ETYPE_REMOTE_PROTECTION, ecode, 1);
915 else
916 siw_init_terminate(qp, TERM_ERROR_LAYER_RDMAP,
917 RDMAP_ETYPE_CATASTROPHIC,
918 RDMAP_ECODE_UNSPECIFIED, 1);
919 return rv;
920 }
921
siw_fastreg_mr(struct ib_pd * pd,struct siw_sqe * sqe)922 static int siw_fastreg_mr(struct ib_pd *pd, struct siw_sqe *sqe)
923 {
924 struct ib_mr *base_mr = (struct ib_mr *)(uintptr_t)sqe->base_mr;
925 struct siw_device *sdev = to_siw_dev(pd->device);
926 struct siw_mem *mem;
927 int rv = 0;
928
929 siw_dbg_pd(pd, "STag 0x%08x\n", sqe->rkey);
930
931 if (unlikely(!base_mr)) {
932 pr_warn("siw: fastreg: STag 0x%08x unknown\n", sqe->rkey);
933 return -EINVAL;
934 }
935
936 if (unlikely(base_mr->rkey >> 8 != sqe->rkey >> 8)) {
937 pr_warn("siw: fastreg: STag 0x%08x: bad MR\n", sqe->rkey);
938 return -EINVAL;
939 }
940
941 mem = siw_mem_id2obj(sdev, sqe->rkey >> 8);
942 if (unlikely(!mem)) {
943 pr_warn("siw: fastreg: STag 0x%08x unknown\n", sqe->rkey);
944 return -EINVAL;
945 }
946
947 if (unlikely(mem->pd != pd)) {
948 pr_warn("siw: fastreg: PD mismatch\n");
949 rv = -EINVAL;
950 goto out;
951 }
952 if (unlikely(mem->stag_valid)) {
953 pr_warn("siw: fastreg: STag 0x%08x already valid\n", sqe->rkey);
954 rv = -EINVAL;
955 goto out;
956 }
957 /* Refresh STag since user may have changed key part */
958 mem->stag = sqe->rkey;
959 mem->perms = sqe->access;
960
961 siw_dbg_mem(mem, "STag 0x%08x now valid\n", sqe->rkey);
962 mem->va = base_mr->iova;
963 mem->stag_valid = 1;
964 out:
965 siw_mem_put(mem);
966 return rv;
967 }
968
siw_qp_sq_proc_local(struct siw_qp * qp,struct siw_wqe * wqe)969 static int siw_qp_sq_proc_local(struct siw_qp *qp, struct siw_wqe *wqe)
970 {
971 int rv;
972
973 switch (tx_type(wqe)) {
974 case SIW_OP_REG_MR:
975 rv = siw_fastreg_mr(qp->pd, &wqe->sqe);
976 break;
977
978 case SIW_OP_INVAL_STAG:
979 rv = siw_invalidate_stag(qp->pd, wqe->sqe.rkey);
980 break;
981
982 default:
983 rv = -EINVAL;
984 }
985 return rv;
986 }
987
988 /*
989 * siw_qp_sq_process()
990 *
991 * Core TX path routine for RDMAP/DDP/MPA using a TCP kernel socket.
992 * Sends RDMAP payload for the current SQ WR @wqe of @qp in one or more
993 * MPA FPDUs, each containing a DDP segment.
994 *
995 * SQ processing may occur in user context as a result of posting
996 * new WQE's or from siw_tx_thread context. Processing in
997 * user context is limited to non-kernel verbs users.
998 *
999 * SQ processing may get paused anytime, possibly in the middle of a WR
1000 * or FPDU, if insufficient send space is available. SQ processing
1001 * gets resumed from siw_tx_thread, if send space becomes available again.
1002 *
1003 * Must be called with the QP state read-locked.
1004 *
1005 * Note:
1006 * An outbound RREQ can be satisfied by the corresponding RRESP
1007 * _before_ it gets assigned to the ORQ. This happens regularly
1008 * in RDMA READ via loopback case. Since both outbound RREQ and
1009 * inbound RRESP can be handled by the same CPU, locking the ORQ
1010 * is dead-lock prone and thus not an option. With that, the
1011 * RREQ gets assigned to the ORQ _before_ being sent - see
1012 * siw_activate_tx() - and pulled back in case of send failure.
1013 */
siw_qp_sq_process(struct siw_qp * qp)1014 int siw_qp_sq_process(struct siw_qp *qp)
1015 {
1016 struct siw_wqe *wqe = tx_wqe(qp);
1017 enum siw_opcode tx_type;
1018 unsigned long flags;
1019 int rv = 0;
1020
1021 siw_dbg_qp(qp, "enter for type %d\n", tx_type(wqe));
1022
1023 next_wqe:
1024 /*
1025 * Stop QP processing if SQ state changed
1026 */
1027 if (unlikely(qp->tx_ctx.tx_suspend)) {
1028 siw_dbg_qp(qp, "tx suspended\n");
1029 goto done;
1030 }
1031 tx_type = tx_type(wqe);
1032
1033 if (tx_type <= SIW_OP_READ_RESPONSE)
1034 rv = siw_qp_sq_proc_tx(qp, wqe);
1035 else
1036 rv = siw_qp_sq_proc_local(qp, wqe);
1037
1038 if (!rv) {
1039 /*
1040 * WQE processing done
1041 */
1042 switch (tx_type) {
1043 case SIW_OP_SEND:
1044 case SIW_OP_SEND_REMOTE_INV:
1045 case SIW_OP_WRITE:
1046 siw_wqe_put_mem(wqe, tx_type);
1047 fallthrough;
1048
1049 case SIW_OP_INVAL_STAG:
1050 case SIW_OP_REG_MR:
1051 if (tx_flags(wqe) & SIW_WQE_SIGNALLED)
1052 siw_sqe_complete(qp, &wqe->sqe, wqe->bytes,
1053 SIW_WC_SUCCESS);
1054 break;
1055
1056 case SIW_OP_READ:
1057 case SIW_OP_READ_LOCAL_INV:
1058 /*
1059 * already enqueued to ORQ queue
1060 */
1061 break;
1062
1063 case SIW_OP_READ_RESPONSE:
1064 siw_wqe_put_mem(wqe, tx_type);
1065 break;
1066
1067 default:
1068 WARN(1, "undefined WQE type %d\n", tx_type);
1069 rv = -EINVAL;
1070 goto done;
1071 }
1072
1073 spin_lock_irqsave(&qp->sq_lock, flags);
1074 wqe->wr_status = SIW_WR_IDLE;
1075 rv = siw_activate_tx(qp);
1076 spin_unlock_irqrestore(&qp->sq_lock, flags);
1077
1078 if (rv <= 0)
1079 goto done;
1080
1081 goto next_wqe;
1082
1083 } else if (rv == -EAGAIN) {
1084 siw_dbg_qp(qp, "sq paused: hd/tr %d of %d, data %d\n",
1085 qp->tx_ctx.ctrl_sent, qp->tx_ctx.ctrl_len,
1086 qp->tx_ctx.bytes_unsent);
1087 rv = 0;
1088 goto done;
1089 } else if (rv == -EINPROGRESS) {
1090 rv = siw_sq_start(qp);
1091 goto done;
1092 } else {
1093 /*
1094 * WQE processing failed.
1095 * Verbs 8.3.2:
1096 * o It turns any WQE into a signalled WQE.
1097 * o Local catastrophic error must be surfaced
1098 * o QP must be moved into Terminate state: done by code
1099 * doing socket state change processing
1100 *
1101 * o TODO: Termination message must be sent.
1102 * o TODO: Implement more precise work completion errors,
1103 * see enum ib_wc_status in ib_verbs.h
1104 */
1105 siw_dbg_qp(qp, "wqe type %d processing failed: %d\n",
1106 tx_type(wqe), rv);
1107
1108 spin_lock_irqsave(&qp->sq_lock, flags);
1109 /*
1110 * RREQ may have already been completed by inbound RRESP!
1111 */
1112 if ((tx_type == SIW_OP_READ ||
1113 tx_type == SIW_OP_READ_LOCAL_INV) && qp->attrs.orq_size) {
1114 /* Cleanup pending entry in ORQ */
1115 qp->orq_put--;
1116 qp->orq[qp->orq_put % qp->attrs.orq_size].flags = 0;
1117 }
1118 spin_unlock_irqrestore(&qp->sq_lock, flags);
1119 /*
1120 * immediately suspends further TX processing
1121 */
1122 if (!qp->tx_ctx.tx_suspend)
1123 siw_qp_cm_drop(qp, 0);
1124
1125 switch (tx_type) {
1126 case SIW_OP_SEND:
1127 case SIW_OP_SEND_REMOTE_INV:
1128 case SIW_OP_SEND_WITH_IMM:
1129 case SIW_OP_WRITE:
1130 case SIW_OP_READ:
1131 case SIW_OP_READ_LOCAL_INV:
1132 siw_wqe_put_mem(wqe, tx_type);
1133 fallthrough;
1134
1135 case SIW_OP_INVAL_STAG:
1136 case SIW_OP_REG_MR:
1137 siw_sqe_complete(qp, &wqe->sqe, wqe->bytes,
1138 SIW_WC_LOC_QP_OP_ERR);
1139
1140 siw_qp_event(qp, IB_EVENT_QP_FATAL);
1141
1142 break;
1143
1144 case SIW_OP_READ_RESPONSE:
1145 siw_dbg_qp(qp, "proc. read.response failed: %d\n", rv);
1146
1147 siw_qp_event(qp, IB_EVENT_QP_REQ_ERR);
1148
1149 siw_wqe_put_mem(wqe, SIW_OP_READ_RESPONSE);
1150
1151 break;
1152
1153 default:
1154 WARN(1, "undefined WQE type %d\n", tx_type);
1155 rv = -EINVAL;
1156 }
1157 wqe->wr_status = SIW_WR_IDLE;
1158 }
1159 done:
1160 return rv;
1161 }
1162
siw_sq_resume(struct siw_qp * qp)1163 static void siw_sq_resume(struct siw_qp *qp)
1164 {
1165 if (down_read_trylock(&qp->state_lock)) {
1166 if (likely(qp->attrs.state == SIW_QP_STATE_RTS &&
1167 !qp->tx_ctx.tx_suspend)) {
1168 int rv = siw_qp_sq_process(qp);
1169
1170 up_read(&qp->state_lock);
1171
1172 if (unlikely(rv < 0)) {
1173 siw_dbg_qp(qp, "SQ task failed: err %d\n", rv);
1174
1175 if (!qp->tx_ctx.tx_suspend)
1176 siw_qp_cm_drop(qp, 0);
1177 }
1178 } else {
1179 up_read(&qp->state_lock);
1180 }
1181 } else {
1182 siw_dbg_qp(qp, "Resume SQ while QP locked\n");
1183 }
1184 siw_qp_put(qp);
1185 }
1186
1187 struct tx_task_t {
1188 struct llist_head active;
1189 wait_queue_head_t waiting;
1190 };
1191
1192 static DEFINE_PER_CPU(struct tx_task_t, siw_tx_task_g);
1193
siw_create_tx_threads(void)1194 int siw_create_tx_threads(void)
1195 {
1196 int cpu, assigned = 0;
1197
1198 for_each_online_cpu(cpu) {
1199 struct tx_task_t *tx_task;
1200
1201 /* Skip HT cores */
1202 if (cpu % cpumask_weight(topology_sibling_cpumask(cpu)))
1203 continue;
1204
1205 tx_task = &per_cpu(siw_tx_task_g, cpu);
1206 init_llist_head(&tx_task->active);
1207 init_waitqueue_head(&tx_task->waiting);
1208
1209 siw_tx_thread[cpu] =
1210 kthread_run_on_cpu(siw_run_sq,
1211 (unsigned long *)(long)cpu,
1212 cpu, "siw_tx/%u");
1213 if (IS_ERR(siw_tx_thread[cpu])) {
1214 siw_tx_thread[cpu] = NULL;
1215 continue;
1216 }
1217 assigned++;
1218 }
1219 return assigned;
1220 }
1221
siw_stop_tx_threads(void)1222 void siw_stop_tx_threads(void)
1223 {
1224 int cpu;
1225
1226 for_each_possible_cpu(cpu) {
1227 if (siw_tx_thread[cpu]) {
1228 kthread_stop(siw_tx_thread[cpu]);
1229 wake_up(&per_cpu(siw_tx_task_g, cpu).waiting);
1230 siw_tx_thread[cpu] = NULL;
1231 }
1232 }
1233 }
1234
siw_run_sq(void * data)1235 int siw_run_sq(void *data)
1236 {
1237 const int nr_cpu = (unsigned int)(long)data;
1238 struct llist_node *active;
1239 struct siw_qp *qp;
1240 struct tx_task_t *tx_task = &per_cpu(siw_tx_task_g, nr_cpu);
1241
1242 while (1) {
1243 struct llist_node *fifo_list = NULL;
1244
1245 wait_event_interruptible(tx_task->waiting,
1246 !llist_empty(&tx_task->active) ||
1247 kthread_should_stop());
1248
1249 if (kthread_should_stop())
1250 break;
1251
1252 active = llist_del_all(&tx_task->active);
1253 /*
1254 * llist_del_all returns a list with newest entry first.
1255 * Re-order list for fairness among QP's.
1256 */
1257 fifo_list = llist_reverse_order(active);
1258 while (fifo_list) {
1259 qp = container_of(fifo_list, struct siw_qp, tx_list);
1260 fifo_list = llist_next(fifo_list);
1261 qp->tx_list.next = NULL;
1262
1263 siw_sq_resume(qp);
1264 }
1265 }
1266 active = llist_del_all(&tx_task->active);
1267 if (active) {
1268 llist_for_each_entry(qp, active, tx_list) {
1269 qp->tx_list.next = NULL;
1270 siw_sq_resume(qp);
1271 }
1272 }
1273 return 0;
1274 }
1275
siw_sq_start(struct siw_qp * qp)1276 int siw_sq_start(struct siw_qp *qp)
1277 {
1278 if (tx_wqe(qp)->wr_status == SIW_WR_IDLE)
1279 return 0;
1280
1281 if (unlikely(!cpu_online(qp->tx_cpu))) {
1282 siw_put_tx_cpu(qp->tx_cpu);
1283 qp->tx_cpu = siw_get_tx_cpu(qp->sdev);
1284 if (qp->tx_cpu < 0) {
1285 pr_warn("siw: no tx cpu available\n");
1286
1287 return -EIO;
1288 }
1289 }
1290 siw_qp_get(qp);
1291
1292 llist_add(&qp->tx_list, &per_cpu(siw_tx_task_g, qp->tx_cpu).active);
1293
1294 wake_up(&per_cpu(siw_tx_task_g, qp->tx_cpu).waiting);
1295
1296 return 0;
1297 }
1298