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
37 /*
38 * Copy short payload at provided destination payload address
39 */
siw_try_1seg(struct siw_iwarp_tx * c_tx,void * paddr)40 static int siw_try_1seg(struct siw_iwarp_tx *c_tx, void *paddr)
41 {
42 struct siw_wqe *wqe = &c_tx->wqe_active;
43 struct siw_sge *sge = &wqe->sqe.sge[0];
44 u32 bytes = sge->length;
45
46 if (bytes > MAX_HDR_INLINE || wqe->sqe.num_sge != 1)
47 return MAX_HDR_INLINE + 1;
48
49 if (!bytes)
50 return 0;
51
52 if (tx_flags(wqe) & SIW_WQE_INLINE) {
53 memcpy(paddr, &wqe->sqe.sge[1], bytes);
54 } else {
55 struct siw_mem *mem = wqe->mem[0];
56
57 if (!mem->mem_obj) {
58 /* Kernel client using kva */
59 memcpy(paddr, ib_virt_dma_to_ptr(sge->laddr), bytes);
60 } else if (c_tx->in_syscall) {
61 if (copy_from_user(paddr, u64_to_user_ptr(sge->laddr),
62 bytes))
63 return -EFAULT;
64 } else {
65 unsigned int off = sge->laddr & ~PAGE_MASK;
66 struct page *p;
67 char *buffer;
68 int pbl_idx = 0;
69
70 if (!mem->is_pbl)
71 p = siw_get_upage(mem->umem, sge->laddr);
72 else
73 p = siw_get_pblpage(mem, sge->laddr, &pbl_idx);
74
75 if (unlikely(!p))
76 return -EFAULT;
77
78 buffer = kmap_local_page(p);
79
80 if (likely(PAGE_SIZE - off >= bytes)) {
81 memcpy(paddr, buffer + off, bytes);
82 } else {
83 unsigned long part = bytes - (PAGE_SIZE - off);
84
85 memcpy(paddr, buffer + off, part);
86 kunmap_local(buffer);
87
88 if (!mem->is_pbl)
89 p = siw_get_upage(mem->umem,
90 sge->laddr + part);
91 else
92 p = siw_get_pblpage(mem,
93 sge->laddr + part,
94 &pbl_idx);
95 if (unlikely(!p))
96 return -EFAULT;
97
98 buffer = kmap_local_page(p);
99 memcpy(paddr + part, buffer, bytes - part);
100 }
101 kunmap_local(buffer);
102 }
103 }
104 return (int)bytes;
105 }
106
107 #define PKT_FRAGMENTED 1
108 #define PKT_COMPLETE 0
109
110 /*
111 * siw_qp_prepare_tx()
112 *
113 * Prepare tx state for sending out one fpdu. Builds complete pkt
114 * if no user data or only immediate data are present.
115 *
116 * returns PKT_COMPLETE if complete pkt built, PKT_FRAGMENTED otherwise.
117 */
siw_qp_prepare_tx(struct siw_iwarp_tx * c_tx)118 static int siw_qp_prepare_tx(struct siw_iwarp_tx *c_tx)
119 {
120 struct siw_wqe *wqe = &c_tx->wqe_active;
121 char *crc = NULL;
122 int data = 0;
123
124 switch (tx_type(wqe)) {
125 case SIW_OP_READ:
126 case SIW_OP_READ_LOCAL_INV:
127 memcpy(&c_tx->pkt.ctrl,
128 &iwarp_pktinfo[RDMAP_RDMA_READ_REQ].ctrl,
129 sizeof(struct iwarp_ctrl));
130
131 c_tx->pkt.rreq.rsvd = 0;
132 c_tx->pkt.rreq.ddp_qn = htonl(RDMAP_UNTAGGED_QN_RDMA_READ);
133 c_tx->pkt.rreq.ddp_msn =
134 htonl(++c_tx->ddp_msn[RDMAP_UNTAGGED_QN_RDMA_READ]);
135 c_tx->pkt.rreq.ddp_mo = 0;
136 c_tx->pkt.rreq.sink_stag = htonl(wqe->sqe.sge[0].lkey);
137 c_tx->pkt.rreq.sink_to =
138 cpu_to_be64(wqe->sqe.sge[0].laddr);
139 c_tx->pkt.rreq.source_stag = htonl(wqe->sqe.rkey);
140 c_tx->pkt.rreq.source_to = cpu_to_be64(wqe->sqe.raddr);
141 c_tx->pkt.rreq.read_size = htonl(wqe->sqe.sge[0].length);
142
143 c_tx->ctrl_len = sizeof(struct iwarp_rdma_rreq);
144 crc = (char *)&c_tx->pkt.rreq_pkt.crc;
145 break;
146
147 case SIW_OP_SEND:
148 if (tx_flags(wqe) & SIW_WQE_SOLICITED)
149 memcpy(&c_tx->pkt.ctrl,
150 &iwarp_pktinfo[RDMAP_SEND_SE].ctrl,
151 sizeof(struct iwarp_ctrl));
152 else
153 memcpy(&c_tx->pkt.ctrl, &iwarp_pktinfo[RDMAP_SEND].ctrl,
154 sizeof(struct iwarp_ctrl));
155
156 c_tx->pkt.send.ddp_qn = RDMAP_UNTAGGED_QN_SEND;
157 c_tx->pkt.send.ddp_msn =
158 htonl(++c_tx->ddp_msn[RDMAP_UNTAGGED_QN_SEND]);
159 c_tx->pkt.send.ddp_mo = 0;
160
161 c_tx->pkt.send_inv.inval_stag = 0;
162
163 c_tx->ctrl_len = sizeof(struct iwarp_send);
164
165 crc = (char *)&c_tx->pkt.send_pkt.crc;
166 data = siw_try_1seg(c_tx, crc);
167 break;
168
169 case SIW_OP_SEND_REMOTE_INV:
170 if (tx_flags(wqe) & SIW_WQE_SOLICITED)
171 memcpy(&c_tx->pkt.ctrl,
172 &iwarp_pktinfo[RDMAP_SEND_SE_INVAL].ctrl,
173 sizeof(struct iwarp_ctrl));
174 else
175 memcpy(&c_tx->pkt.ctrl,
176 &iwarp_pktinfo[RDMAP_SEND_INVAL].ctrl,
177 sizeof(struct iwarp_ctrl));
178
179 c_tx->pkt.send.ddp_qn = RDMAP_UNTAGGED_QN_SEND;
180 c_tx->pkt.send.ddp_msn =
181 htonl(++c_tx->ddp_msn[RDMAP_UNTAGGED_QN_SEND]);
182 c_tx->pkt.send.ddp_mo = 0;
183
184 c_tx->pkt.send_inv.inval_stag = cpu_to_be32(wqe->sqe.rkey);
185
186 c_tx->ctrl_len = sizeof(struct iwarp_send_inv);
187
188 crc = (char *)&c_tx->pkt.send_pkt.crc;
189 data = siw_try_1seg(c_tx, crc);
190 break;
191
192 case SIW_OP_WRITE:
193 memcpy(&c_tx->pkt.ctrl, &iwarp_pktinfo[RDMAP_RDMA_WRITE].ctrl,
194 sizeof(struct iwarp_ctrl));
195
196 c_tx->pkt.rwrite.sink_stag = htonl(wqe->sqe.rkey);
197 c_tx->pkt.rwrite.sink_to = cpu_to_be64(wqe->sqe.raddr);
198 c_tx->ctrl_len = sizeof(struct iwarp_rdma_write);
199
200 crc = (char *)&c_tx->pkt.write_pkt.crc;
201 data = siw_try_1seg(c_tx, crc);
202 break;
203
204 case SIW_OP_READ_RESPONSE:
205 memcpy(&c_tx->pkt.ctrl,
206 &iwarp_pktinfo[RDMAP_RDMA_READ_RESP].ctrl,
207 sizeof(struct iwarp_ctrl));
208
209 /* NBO */
210 c_tx->pkt.rresp.sink_stag = cpu_to_be32(wqe->sqe.rkey);
211 c_tx->pkt.rresp.sink_to = cpu_to_be64(wqe->sqe.raddr);
212
213 c_tx->ctrl_len = sizeof(struct iwarp_rdma_rresp);
214
215 crc = (char *)&c_tx->pkt.write_pkt.crc;
216 data = siw_try_1seg(c_tx, crc);
217 break;
218
219 default:
220 siw_dbg_qp(tx_qp(c_tx), "stale wqe type %d\n", tx_type(wqe));
221 return -EOPNOTSUPP;
222 }
223 if (unlikely(data < 0))
224 return data;
225
226 c_tx->ctrl_sent = 0;
227
228 if (data <= MAX_HDR_INLINE) {
229 if (data) {
230 wqe->processed = data;
231
232 c_tx->pkt.ctrl.mpa_len =
233 htons(c_tx->ctrl_len + data - MPA_HDR_SIZE);
234
235 /* Add pad, if needed */
236 data += -(int)data & 0x3;
237 /* advance CRC location after payload */
238 crc += data;
239 c_tx->ctrl_len += data;
240
241 if (!(c_tx->pkt.ctrl.ddp_rdmap_ctrl & DDP_FLAG_TAGGED))
242 c_tx->pkt.c_untagged.ddp_mo = 0;
243 else
244 c_tx->pkt.c_tagged.ddp_to =
245 cpu_to_be64(wqe->sqe.raddr);
246 }
247
248 *(u32 *)crc = 0;
249 /*
250 * Do complete CRC if enabled and short packet
251 */
252 if (c_tx->mpa_crc_hd) {
253 crypto_shash_init(c_tx->mpa_crc_hd);
254 if (crypto_shash_update(c_tx->mpa_crc_hd,
255 (u8 *)&c_tx->pkt,
256 c_tx->ctrl_len))
257 return -EINVAL;
258 crypto_shash_final(c_tx->mpa_crc_hd, (u8 *)crc);
259 }
260 c_tx->ctrl_len += MPA_CRC_SIZE;
261
262 return PKT_COMPLETE;
263 }
264 c_tx->ctrl_len += MPA_CRC_SIZE;
265 c_tx->sge_idx = 0;
266 c_tx->sge_off = 0;
267 c_tx->pbl_idx = 0;
268
269 /*
270 * Allow direct sending out of user buffer if WR is non signalled
271 * and payload is over threshold.
272 * Per RDMA verbs, the application should not change the send buffer
273 * until the work completed. In iWarp, work completion is only
274 * local delivery to TCP. TCP may reuse the buffer for
275 * retransmission. Changing unsent data also breaks the CRC,
276 * if applied.
277 */
278 if (c_tx->zcopy_tx && wqe->bytes >= SENDPAGE_THRESH &&
279 !(tx_flags(wqe) & SIW_WQE_SIGNALLED))
280 c_tx->use_sendpage = 1;
281 else
282 c_tx->use_sendpage = 0;
283
284 return PKT_FRAGMENTED;
285 }
286
287 /*
288 * Send out one complete control type FPDU, or header of FPDU carrying
289 * data. Used for fixed sized packets like Read.Requests or zero length
290 * SENDs, WRITEs, READ.Responses, or header only.
291 */
siw_tx_ctrl(struct siw_iwarp_tx * c_tx,struct socket * s,int flags)292 static int siw_tx_ctrl(struct siw_iwarp_tx *c_tx, struct socket *s,
293 int flags)
294 {
295 struct msghdr msg = { .msg_flags = flags };
296 struct kvec iov = { .iov_base =
297 (char *)&c_tx->pkt.ctrl + c_tx->ctrl_sent,
298 .iov_len = c_tx->ctrl_len - c_tx->ctrl_sent };
299
300 int rv = kernel_sendmsg(s, &msg, &iov, 1,
301 c_tx->ctrl_len - c_tx->ctrl_sent);
302
303 if (rv >= 0) {
304 c_tx->ctrl_sent += rv;
305
306 if (c_tx->ctrl_sent == c_tx->ctrl_len)
307 rv = 0;
308 else
309 rv = -EAGAIN;
310 }
311 return rv;
312 }
313
314 /*
315 * 0copy TCP transmit interface: Use MSG_SPLICE_PAGES.
316 *
317 * Using sendpage to push page by page appears to be less efficient
318 * than using sendmsg, even if data are copied.
319 *
320 * A general performance limitation might be the extra four bytes
321 * trailer checksum segment to be pushed after user data.
322 */
siw_tcp_sendpages(struct socket * s,struct page ** page,int offset,size_t size)323 static int siw_tcp_sendpages(struct socket *s, struct page **page, int offset,
324 size_t size)
325 {
326 struct bio_vec bvec;
327 struct msghdr msg = {
328 .msg_flags = (MSG_MORE | MSG_DONTWAIT | MSG_SPLICE_PAGES),
329 };
330 struct sock *sk = s->sk;
331 int i = 0, rv = 0, sent = 0;
332
333 while (size) {
334 size_t bytes = min_t(size_t, PAGE_SIZE - offset, size);
335
336 if (size + offset <= PAGE_SIZE)
337 msg.msg_flags &= ~MSG_MORE;
338
339 tcp_rate_check_app_limited(sk);
340 bvec_set_page(&bvec, page[i], bytes, offset);
341 iov_iter_bvec(&msg.msg_iter, ITER_SOURCE, &bvec, 1, size);
342
343 try_page_again:
344 lock_sock(sk);
345 rv = tcp_sendmsg_locked(sk, &msg, size);
346 release_sock(sk);
347
348 if (rv > 0) {
349 size -= rv;
350 sent += rv;
351 if (rv != bytes) {
352 offset += rv;
353 bytes -= rv;
354 goto try_page_again;
355 }
356 offset = 0;
357 } else {
358 if (rv == -EAGAIN || rv == 0)
359 break;
360 return rv;
361 }
362 i++;
363 }
364 return sent;
365 }
366
367 /*
368 * siw_0copy_tx()
369 *
370 * Pushes list of pages to TCP socket. If pages from multiple
371 * SGE's, all referenced pages of each SGE are pushed in one
372 * shot.
373 */
siw_0copy_tx(struct socket * s,struct page ** page,struct siw_sge * sge,unsigned int offset,unsigned int size)374 static int siw_0copy_tx(struct socket *s, struct page **page,
375 struct siw_sge *sge, unsigned int offset,
376 unsigned int size)
377 {
378 int i = 0, sent = 0, rv;
379 int sge_bytes = min(sge->length - offset, size);
380
381 offset = (sge->laddr + offset) & ~PAGE_MASK;
382
383 while (sent != size) {
384 rv = siw_tcp_sendpages(s, &page[i], offset, sge_bytes);
385 if (rv >= 0) {
386 sent += rv;
387 if (size == sent || sge_bytes > rv)
388 break;
389
390 i += PAGE_ALIGN(sge_bytes + offset) >> PAGE_SHIFT;
391 sge++;
392 sge_bytes = min(sge->length, size - sent);
393 offset = sge->laddr & ~PAGE_MASK;
394 } else {
395 sent = rv;
396 break;
397 }
398 }
399 return sent;
400 }
401
402 #define MAX_TRAILER (MPA_CRC_SIZE + 4)
403
siw_unmap_pages(struct kvec * iov,unsigned long kmap_mask,int len)404 static void siw_unmap_pages(struct kvec *iov, unsigned long kmap_mask, int len)
405 {
406 int i;
407
408 /*
409 * Work backwards through the array to honor the kmap_local_page()
410 * ordering requirements.
411 */
412 for (i = (len-1); i >= 0; i--) {
413 if (kmap_mask & BIT(i)) {
414 unsigned long addr = (unsigned long)iov[i].iov_base;
415
416 kunmap_local((void *)(addr & PAGE_MASK));
417 }
418 }
419 }
420
421 /*
422 * siw_tx_hdt() tries to push a complete packet to TCP where all
423 * packet fragments are referenced by the elements of one iovec.
424 * For the data portion, each involved page must be referenced by
425 * one extra element. All sge's data can be non-aligned to page
426 * boundaries. Two more elements are referencing iWARP header
427 * and trailer:
428 * MAX_ARRAY = 64KB/PAGE_SIZE + 1 + (2 * (SIW_MAX_SGE - 1) + HDR + TRL
429 */
430 #define MAX_ARRAY ((0xffff / PAGE_SIZE) + 1 + (2 * (SIW_MAX_SGE - 1) + 2))
431
432 /*
433 * Write out iov referencing hdr, data and trailer of current FPDU.
434 * Update transmit state dependent on write return status
435 */
siw_tx_hdt(struct siw_iwarp_tx * c_tx,struct socket * s)436 static int siw_tx_hdt(struct siw_iwarp_tx *c_tx, struct socket *s)
437 {
438 struct siw_wqe *wqe = &c_tx->wqe_active;
439 struct siw_sge *sge = &wqe->sqe.sge[c_tx->sge_idx];
440 struct kvec iov[MAX_ARRAY];
441 struct page *page_array[MAX_ARRAY];
442 struct msghdr msg = { .msg_flags = MSG_DONTWAIT | MSG_EOR };
443
444 int seg = 0, do_crc = c_tx->do_crc, is_kva = 0, rv;
445 unsigned int data_len = c_tx->bytes_unsent, hdr_len = 0, trl_len = 0,
446 sge_off = c_tx->sge_off, sge_idx = c_tx->sge_idx,
447 pbl_idx = c_tx->pbl_idx;
448 unsigned long kmap_mask = 0L;
449
450 if (c_tx->state == SIW_SEND_HDR) {
451 if (c_tx->use_sendpage) {
452 rv = siw_tx_ctrl(c_tx, s, MSG_DONTWAIT | MSG_MORE);
453 if (rv)
454 goto done;
455
456 c_tx->state = SIW_SEND_DATA;
457 } else {
458 iov[0].iov_base =
459 (char *)&c_tx->pkt.ctrl + c_tx->ctrl_sent;
460 iov[0].iov_len = hdr_len =
461 c_tx->ctrl_len - c_tx->ctrl_sent;
462 seg = 1;
463 }
464 }
465
466 wqe->processed += data_len;
467
468 while (data_len) { /* walk the list of SGE's */
469 unsigned int sge_len = min(sge->length - sge_off, data_len);
470 unsigned int fp_off = (sge->laddr + sge_off) & ~PAGE_MASK;
471 struct siw_mem *mem;
472
473 if (!(tx_flags(wqe) & SIW_WQE_INLINE)) {
474 mem = wqe->mem[sge_idx];
475 is_kva = mem->mem_obj == NULL ? 1 : 0;
476 } else {
477 is_kva = 1;
478 }
479 if (is_kva && !c_tx->use_sendpage) {
480 /*
481 * tx from kernel virtual address: either inline data
482 * or memory region with assigned kernel buffer
483 */
484 iov[seg].iov_base =
485 ib_virt_dma_to_ptr(sge->laddr + sge_off);
486 iov[seg].iov_len = sge_len;
487
488 if (do_crc)
489 crypto_shash_update(c_tx->mpa_crc_hd,
490 iov[seg].iov_base,
491 sge_len);
492 sge_off += sge_len;
493 data_len -= sge_len;
494 seg++;
495 goto sge_done;
496 }
497
498 while (sge_len) {
499 size_t plen = min((int)PAGE_SIZE - fp_off, sge_len);
500 void *kaddr;
501
502 if (!is_kva) {
503 struct page *p;
504
505 if (mem->is_pbl)
506 p = siw_get_pblpage(
507 mem, sge->laddr + sge_off,
508 &pbl_idx);
509 else
510 p = siw_get_upage(mem->umem,
511 sge->laddr + sge_off);
512 if (unlikely(!p)) {
513 siw_unmap_pages(iov, kmap_mask, seg);
514 wqe->processed -= c_tx->bytes_unsent;
515 rv = -EFAULT;
516 goto done_crc;
517 }
518 page_array[seg] = p;
519
520 if (!c_tx->use_sendpage) {
521 void *kaddr = kmap_local_page(p);
522
523 /* Remember for later kunmap() */
524 kmap_mask |= BIT(seg);
525 iov[seg].iov_base = kaddr + fp_off;
526 iov[seg].iov_len = plen;
527
528 if (do_crc)
529 crypto_shash_update(
530 c_tx->mpa_crc_hd,
531 iov[seg].iov_base,
532 plen);
533 } else if (do_crc) {
534 kaddr = kmap_local_page(p);
535 crypto_shash_update(c_tx->mpa_crc_hd,
536 kaddr + fp_off,
537 plen);
538 kunmap_local(kaddr);
539 }
540 } else {
541 /*
542 * Cast to an uintptr_t to preserve all 64 bits
543 * in sge->laddr.
544 */
545 u64 va = sge->laddr + sge_off;
546
547 page_array[seg] = ib_virt_dma_to_page(va);
548 if (do_crc)
549 crypto_shash_update(
550 c_tx->mpa_crc_hd,
551 ib_virt_dma_to_ptr(va),
552 plen);
553 }
554
555 sge_len -= plen;
556 sge_off += plen;
557 data_len -= plen;
558 fp_off = 0;
559
560 if (++seg >= (int)MAX_ARRAY) {
561 siw_dbg_qp(tx_qp(c_tx), "to many fragments\n");
562 siw_unmap_pages(iov, kmap_mask, seg-1);
563 wqe->processed -= c_tx->bytes_unsent;
564 rv = -EMSGSIZE;
565 goto done_crc;
566 }
567 }
568 sge_done:
569 /* Update SGE variables at end of SGE */
570 if (sge_off == sge->length &&
571 (data_len != 0 || wqe->processed < wqe->bytes)) {
572 sge_idx++;
573 sge++;
574 sge_off = 0;
575 }
576 }
577 /* trailer */
578 if (likely(c_tx->state != SIW_SEND_TRAILER)) {
579 iov[seg].iov_base = &c_tx->trailer.pad[4 - c_tx->pad];
580 iov[seg].iov_len = trl_len = MAX_TRAILER - (4 - c_tx->pad);
581 } else {
582 iov[seg].iov_base = &c_tx->trailer.pad[c_tx->ctrl_sent];
583 iov[seg].iov_len = trl_len = MAX_TRAILER - c_tx->ctrl_sent;
584 }
585
586 if (c_tx->pad) {
587 *(u32 *)c_tx->trailer.pad = 0;
588 if (do_crc)
589 crypto_shash_update(c_tx->mpa_crc_hd,
590 (u8 *)&c_tx->trailer.crc - c_tx->pad,
591 c_tx->pad);
592 }
593 if (!c_tx->mpa_crc_hd)
594 c_tx->trailer.crc = 0;
595 else if (do_crc)
596 crypto_shash_final(c_tx->mpa_crc_hd, (u8 *)&c_tx->trailer.crc);
597
598 data_len = c_tx->bytes_unsent;
599
600 if (c_tx->use_sendpage) {
601 rv = siw_0copy_tx(s, page_array, &wqe->sqe.sge[c_tx->sge_idx],
602 c_tx->sge_off, data_len);
603 if (rv == data_len) {
604 rv = kernel_sendmsg(s, &msg, &iov[seg], 1, trl_len);
605 if (rv > 0)
606 rv += data_len;
607 else
608 rv = data_len;
609 }
610 } else {
611 rv = kernel_sendmsg(s, &msg, iov, seg + 1,
612 hdr_len + data_len + trl_len);
613 siw_unmap_pages(iov, kmap_mask, seg);
614 }
615 if (rv < (int)hdr_len) {
616 /* Not even complete hdr pushed or negative rv */
617 wqe->processed -= data_len;
618 if (rv >= 0) {
619 c_tx->ctrl_sent += rv;
620 rv = -EAGAIN;
621 }
622 goto done_crc;
623 }
624 rv -= hdr_len;
625
626 if (rv >= (int)data_len) {
627 /* all user data pushed to TCP or no data to push */
628 if (data_len > 0 && wqe->processed < wqe->bytes) {
629 /* Save the current state for next tx */
630 c_tx->sge_idx = sge_idx;
631 c_tx->sge_off = sge_off;
632 c_tx->pbl_idx = pbl_idx;
633 }
634 rv -= data_len;
635
636 if (rv == trl_len) /* all pushed */
637 rv = 0;
638 else {
639 c_tx->state = SIW_SEND_TRAILER;
640 c_tx->ctrl_len = MAX_TRAILER;
641 c_tx->ctrl_sent = rv + 4 - c_tx->pad;
642 c_tx->bytes_unsent = 0;
643 rv = -EAGAIN;
644 }
645
646 } else if (data_len > 0) {
647 /* Maybe some user data pushed to TCP */
648 c_tx->state = SIW_SEND_DATA;
649 wqe->processed -= data_len - rv;
650
651 if (rv) {
652 /*
653 * Some bytes out. Recompute tx state based
654 * on old state and bytes pushed
655 */
656 unsigned int sge_unsent;
657
658 c_tx->bytes_unsent -= rv;
659 sge = &wqe->sqe.sge[c_tx->sge_idx];
660 sge_unsent = sge->length - c_tx->sge_off;
661
662 while (sge_unsent <= rv) {
663 rv -= sge_unsent;
664 c_tx->sge_idx++;
665 c_tx->sge_off = 0;
666 sge++;
667 sge_unsent = sge->length;
668 }
669 c_tx->sge_off += rv;
670 }
671 rv = -EAGAIN;
672 }
673 done_crc:
674 c_tx->do_crc = 0;
675 done:
676 return rv;
677 }
678
siw_update_tcpseg(struct siw_iwarp_tx * c_tx,struct socket * s)679 static void siw_update_tcpseg(struct siw_iwarp_tx *c_tx,
680 struct socket *s)
681 {
682 struct tcp_sock *tp = tcp_sk(s->sk);
683
684 if (tp->gso_segs) {
685 if (c_tx->gso_seg_limit == 0)
686 c_tx->tcp_seglen = tp->mss_cache * tp->gso_segs;
687 else
688 c_tx->tcp_seglen =
689 tp->mss_cache *
690 min_t(u16, c_tx->gso_seg_limit, tp->gso_segs);
691 } else {
692 c_tx->tcp_seglen = tp->mss_cache;
693 }
694 /* Loopback may give odd numbers */
695 c_tx->tcp_seglen &= 0xfffffff8;
696 }
697
698 /*
699 * siw_prepare_fpdu()
700 *
701 * Prepares transmit context to send out one FPDU if FPDU will contain
702 * user data and user data are not immediate data.
703 * Computes maximum FPDU length to fill up TCP MSS if possible.
704 *
705 * @qp: QP from which to transmit
706 * @wqe: Current WQE causing transmission
707 *
708 * TODO: Take into account real available sendspace on socket
709 * to avoid header misalignment due to send pausing within
710 * fpdu transmission
711 */
siw_prepare_fpdu(struct siw_qp * qp,struct siw_wqe * wqe)712 static void siw_prepare_fpdu(struct siw_qp *qp, struct siw_wqe *wqe)
713 {
714 struct siw_iwarp_tx *c_tx = &qp->tx_ctx;
715 int data_len;
716
717 c_tx->ctrl_len =
718 iwarp_pktinfo[__rdmap_get_opcode(&c_tx->pkt.ctrl)].hdr_len;
719 c_tx->ctrl_sent = 0;
720
721 /*
722 * Update target buffer offset if any
723 */
724 if (!(c_tx->pkt.ctrl.ddp_rdmap_ctrl & DDP_FLAG_TAGGED))
725 /* Untagged message */
726 c_tx->pkt.c_untagged.ddp_mo = cpu_to_be32(wqe->processed);
727 else /* Tagged message */
728 c_tx->pkt.c_tagged.ddp_to =
729 cpu_to_be64(wqe->sqe.raddr + wqe->processed);
730
731 data_len = wqe->bytes - wqe->processed;
732 if (data_len + c_tx->ctrl_len + MPA_CRC_SIZE > c_tx->tcp_seglen) {
733 /* Trim DDP payload to fit into current TCP segment */
734 data_len = c_tx->tcp_seglen - (c_tx->ctrl_len + MPA_CRC_SIZE);
735 c_tx->pkt.ctrl.ddp_rdmap_ctrl &= ~DDP_FLAG_LAST;
736 c_tx->pad = 0;
737 } else {
738 c_tx->pkt.ctrl.ddp_rdmap_ctrl |= DDP_FLAG_LAST;
739 c_tx->pad = -data_len & 0x3;
740 }
741 c_tx->bytes_unsent = data_len;
742
743 c_tx->pkt.ctrl.mpa_len =
744 htons(c_tx->ctrl_len + data_len - MPA_HDR_SIZE);
745
746 /*
747 * Init MPA CRC computation
748 */
749 if (c_tx->mpa_crc_hd) {
750 crypto_shash_init(c_tx->mpa_crc_hd);
751 crypto_shash_update(c_tx->mpa_crc_hd, (u8 *)&c_tx->pkt,
752 c_tx->ctrl_len);
753 c_tx->do_crc = 1;
754 }
755 }
756
757 /*
758 * siw_check_sgl_tx()
759 *
760 * Check permissions for a list of SGE's (SGL).
761 * A successful check will have all memory referenced
762 * for transmission resolved and assigned to the WQE.
763 *
764 * @pd: Protection Domain SGL should belong to
765 * @wqe: WQE to be checked
766 * @perms: requested access permissions
767 *
768 */
769
siw_check_sgl_tx(struct ib_pd * pd,struct siw_wqe * wqe,enum ib_access_flags perms)770 static int siw_check_sgl_tx(struct ib_pd *pd, struct siw_wqe *wqe,
771 enum ib_access_flags perms)
772 {
773 struct siw_sge *sge = &wqe->sqe.sge[0];
774 int i, len, num_sge = wqe->sqe.num_sge;
775
776 if (unlikely(num_sge > SIW_MAX_SGE))
777 return -EINVAL;
778
779 for (i = 0, len = 0; num_sge; num_sge--, i++, sge++) {
780 /*
781 * rdma verbs: do not check stag for a zero length sge
782 */
783 if (sge->length) {
784 int rv = siw_check_sge(pd, sge, &wqe->mem[i], perms, 0,
785 sge->length);
786
787 if (unlikely(rv != E_ACCESS_OK))
788 return rv;
789 }
790 len += sge->length;
791 }
792 return len;
793 }
794
795 /*
796 * siw_qp_sq_proc_tx()
797 *
798 * Process one WQE which needs transmission on the wire.
799 */
siw_qp_sq_proc_tx(struct siw_qp * qp,struct siw_wqe * wqe)800 static int siw_qp_sq_proc_tx(struct siw_qp *qp, struct siw_wqe *wqe)
801 {
802 struct siw_iwarp_tx *c_tx = &qp->tx_ctx;
803 struct socket *s = qp->attrs.sk;
804 int rv = 0, burst_len = qp->tx_ctx.burst;
805 enum rdmap_ecode ecode = RDMAP_ECODE_CATASTROPHIC_STREAM;
806
807 if (unlikely(wqe->wr_status == SIW_WR_IDLE))
808 return 0;
809
810 if (!burst_len)
811 burst_len = SQ_USER_MAXBURST;
812
813 if (wqe->wr_status == SIW_WR_QUEUED) {
814 if (!(wqe->sqe.flags & SIW_WQE_INLINE)) {
815 if (tx_type(wqe) == SIW_OP_READ_RESPONSE)
816 wqe->sqe.num_sge = 1;
817
818 if (tx_type(wqe) != SIW_OP_READ &&
819 tx_type(wqe) != SIW_OP_READ_LOCAL_INV) {
820 /*
821 * Reference memory to be tx'd w/o checking
822 * access for LOCAL_READ permission, since
823 * not defined in RDMA core.
824 */
825 rv = siw_check_sgl_tx(qp->pd, wqe, 0);
826 if (rv < 0) {
827 if (tx_type(wqe) ==
828 SIW_OP_READ_RESPONSE)
829 ecode = siw_rdmap_error(-rv);
830 rv = -EINVAL;
831 goto tx_error;
832 }
833 wqe->bytes = rv;
834 } else {
835 wqe->bytes = 0;
836 }
837 } else {
838 wqe->bytes = wqe->sqe.sge[0].length;
839 if (!rdma_is_kernel_res(&qp->base_qp.res)) {
840 if (wqe->bytes > SIW_MAX_INLINE) {
841 rv = -EINVAL;
842 goto tx_error;
843 }
844 wqe->sqe.sge[0].laddr =
845 (u64)(uintptr_t)&wqe->sqe.sge[1];
846 }
847 }
848 wqe->wr_status = SIW_WR_INPROGRESS;
849 wqe->processed = 0;
850
851 siw_update_tcpseg(c_tx, s);
852
853 rv = siw_qp_prepare_tx(c_tx);
854 if (rv == PKT_FRAGMENTED) {
855 c_tx->state = SIW_SEND_HDR;
856 siw_prepare_fpdu(qp, wqe);
857 } else if (rv == PKT_COMPLETE) {
858 c_tx->state = SIW_SEND_SHORT_FPDU;
859 } else {
860 goto tx_error;
861 }
862 }
863
864 next_segment:
865 siw_dbg_qp(qp, "wr type %d, state %d, data %u, sent %u, id %llx\n",
866 tx_type(wqe), wqe->wr_status, wqe->bytes, wqe->processed,
867 wqe->sqe.id);
868
869 if (--burst_len == 0) {
870 rv = -EINPROGRESS;
871 goto tx_done;
872 }
873 if (c_tx->state == SIW_SEND_SHORT_FPDU) {
874 enum siw_opcode tx_type = tx_type(wqe);
875 unsigned int msg_flags;
876
877 if (siw_sq_empty(qp) || !siw_tcp_nagle || burst_len == 1)
878 /*
879 * End current TCP segment, if SQ runs empty,
880 * or siw_tcp_nagle is not set, or we bail out
881 * soon due to no burst credit left.
882 */
883 msg_flags = MSG_DONTWAIT;
884 else
885 msg_flags = MSG_DONTWAIT | MSG_MORE;
886
887 rv = siw_tx_ctrl(c_tx, s, msg_flags);
888
889 if (!rv && tx_type != SIW_OP_READ &&
890 tx_type != SIW_OP_READ_LOCAL_INV)
891 wqe->processed = wqe->bytes;
892
893 goto tx_done;
894
895 } else {
896 rv = siw_tx_hdt(c_tx, s);
897 }
898 if (!rv) {
899 /*
900 * One segment sent. Processing completed if last
901 * segment, Do next segment otherwise.
902 */
903 if (unlikely(c_tx->tx_suspend)) {
904 /*
905 * Verbs, 6.4.: Try stopping sending after a full
906 * DDP segment if the connection goes down
907 * (== peer halfclose)
908 */
909 rv = -ECONNABORTED;
910 goto tx_done;
911 }
912 if (c_tx->pkt.ctrl.ddp_rdmap_ctrl & DDP_FLAG_LAST) {
913 siw_dbg_qp(qp, "WQE completed\n");
914 goto tx_done;
915 }
916 c_tx->state = SIW_SEND_HDR;
917
918 siw_update_tcpseg(c_tx, s);
919
920 siw_prepare_fpdu(qp, wqe);
921 goto next_segment;
922 }
923 tx_done:
924 qp->tx_ctx.burst = burst_len;
925 return rv;
926
927 tx_error:
928 if (ecode != RDMAP_ECODE_CATASTROPHIC_STREAM)
929 siw_init_terminate(qp, TERM_ERROR_LAYER_RDMAP,
930 RDMAP_ETYPE_REMOTE_PROTECTION, ecode, 1);
931 else
932 siw_init_terminate(qp, TERM_ERROR_LAYER_RDMAP,
933 RDMAP_ETYPE_CATASTROPHIC,
934 RDMAP_ECODE_UNSPECIFIED, 1);
935 return rv;
936 }
937
siw_fastreg_mr(struct ib_pd * pd,struct siw_sqe * sqe)938 static int siw_fastreg_mr(struct ib_pd *pd, struct siw_sqe *sqe)
939 {
940 struct ib_mr *base_mr = (struct ib_mr *)(uintptr_t)sqe->base_mr;
941 struct siw_device *sdev = to_siw_dev(pd->device);
942 struct siw_mem *mem;
943 int rv = 0;
944
945 siw_dbg_pd(pd, "STag 0x%08x\n", sqe->rkey);
946
947 if (unlikely(!base_mr)) {
948 pr_warn("siw: fastreg: STag 0x%08x unknown\n", sqe->rkey);
949 return -EINVAL;
950 }
951
952 if (unlikely(base_mr->rkey >> 8 != sqe->rkey >> 8)) {
953 pr_warn("siw: fastreg: STag 0x%08x: bad MR\n", sqe->rkey);
954 return -EINVAL;
955 }
956
957 mem = siw_mem_id2obj(sdev, sqe->rkey >> 8);
958 if (unlikely(!mem)) {
959 pr_warn("siw: fastreg: STag 0x%08x unknown\n", sqe->rkey);
960 return -EINVAL;
961 }
962
963 if (unlikely(mem->pd != pd)) {
964 pr_warn("siw: fastreg: PD mismatch\n");
965 rv = -EINVAL;
966 goto out;
967 }
968 if (unlikely(mem->stag_valid)) {
969 pr_warn("siw: fastreg: STag 0x%08x already valid\n", sqe->rkey);
970 rv = -EINVAL;
971 goto out;
972 }
973 /* Refresh STag since user may have changed key part */
974 mem->stag = sqe->rkey;
975 mem->perms = sqe->access;
976
977 siw_dbg_mem(mem, "STag 0x%08x now valid\n", sqe->rkey);
978 mem->va = base_mr->iova;
979 mem->stag_valid = 1;
980 out:
981 siw_mem_put(mem);
982 return rv;
983 }
984
siw_qp_sq_proc_local(struct siw_qp * qp,struct siw_wqe * wqe)985 static int siw_qp_sq_proc_local(struct siw_qp *qp, struct siw_wqe *wqe)
986 {
987 int rv;
988
989 switch (tx_type(wqe)) {
990 case SIW_OP_REG_MR:
991 rv = siw_fastreg_mr(qp->pd, &wqe->sqe);
992 break;
993
994 case SIW_OP_INVAL_STAG:
995 rv = siw_invalidate_stag(qp->pd, wqe->sqe.rkey);
996 break;
997
998 default:
999 rv = -EINVAL;
1000 }
1001 return rv;
1002 }
1003
1004 /*
1005 * siw_qp_sq_process()
1006 *
1007 * Core TX path routine for RDMAP/DDP/MPA using a TCP kernel socket.
1008 * Sends RDMAP payload for the current SQ WR @wqe of @qp in one or more
1009 * MPA FPDUs, each containing a DDP segment.
1010 *
1011 * SQ processing may occur in user context as a result of posting
1012 * new WQE's or from siw_sq_work_handler() context. Processing in
1013 * user context is limited to non-kernel verbs users.
1014 *
1015 * SQ processing may get paused anytime, possibly in the middle of a WR
1016 * or FPDU, if insufficient send space is available. SQ processing
1017 * gets resumed from siw_sq_work_handler(), if send space becomes
1018 * available again.
1019 *
1020 * Must be called with the QP state read-locked.
1021 *
1022 * Note:
1023 * An outbound RREQ can be satisfied by the corresponding RRESP
1024 * _before_ it gets assigned to the ORQ. This happens regularly
1025 * in RDMA READ via loopback case. Since both outbound RREQ and
1026 * inbound RRESP can be handled by the same CPU, locking the ORQ
1027 * is dead-lock prone and thus not an option. With that, the
1028 * RREQ gets assigned to the ORQ _before_ being sent - see
1029 * siw_activate_tx() - and pulled back in case of send failure.
1030 */
siw_qp_sq_process(struct siw_qp * qp)1031 int siw_qp_sq_process(struct siw_qp *qp)
1032 {
1033 struct siw_wqe *wqe = tx_wqe(qp);
1034 enum siw_opcode tx_type;
1035 unsigned long flags;
1036 int rv = 0;
1037
1038 siw_dbg_qp(qp, "enter for type %d\n", tx_type(wqe));
1039
1040 next_wqe:
1041 /*
1042 * Stop QP processing if SQ state changed
1043 */
1044 if (unlikely(qp->tx_ctx.tx_suspend)) {
1045 siw_dbg_qp(qp, "tx suspended\n");
1046 goto done;
1047 }
1048 tx_type = tx_type(wqe);
1049
1050 if (tx_type <= SIW_OP_READ_RESPONSE)
1051 rv = siw_qp_sq_proc_tx(qp, wqe);
1052 else
1053 rv = siw_qp_sq_proc_local(qp, wqe);
1054
1055 if (!rv) {
1056 /*
1057 * WQE processing done
1058 */
1059 switch (tx_type) {
1060 case SIW_OP_SEND:
1061 case SIW_OP_SEND_REMOTE_INV:
1062 case SIW_OP_WRITE:
1063 siw_wqe_put_mem(wqe, tx_type);
1064 fallthrough;
1065
1066 case SIW_OP_INVAL_STAG:
1067 case SIW_OP_REG_MR:
1068 if (tx_flags(wqe) & SIW_WQE_SIGNALLED)
1069 siw_sqe_complete(qp, &wqe->sqe, wqe->bytes,
1070 SIW_WC_SUCCESS);
1071 break;
1072
1073 case SIW_OP_READ:
1074 case SIW_OP_READ_LOCAL_INV:
1075 /*
1076 * already enqueued to ORQ queue
1077 */
1078 break;
1079
1080 case SIW_OP_READ_RESPONSE:
1081 siw_wqe_put_mem(wqe, tx_type);
1082 break;
1083
1084 default:
1085 WARN(1, "undefined WQE type %d\n", tx_type);
1086 rv = -EINVAL;
1087 goto done;
1088 }
1089
1090 spin_lock_irqsave(&qp->sq_lock, flags);
1091 wqe->wr_status = SIW_WR_IDLE;
1092 rv = siw_activate_tx(qp);
1093 spin_unlock_irqrestore(&qp->sq_lock, flags);
1094
1095 if (rv <= 0)
1096 goto done;
1097
1098 goto next_wqe;
1099
1100 } else if (rv == -EAGAIN) {
1101 siw_dbg_qp(qp, "sq paused: hd/tr %d of %d, data %d\n",
1102 qp->tx_ctx.ctrl_sent, qp->tx_ctx.ctrl_len,
1103 qp->tx_ctx.bytes_unsent);
1104 rv = 0;
1105 goto done;
1106 } else if (rv == -EINPROGRESS) {
1107 rv = siw_sq_start(qp);
1108 goto done;
1109 } else {
1110 /*
1111 * WQE processing failed.
1112 * Verbs 8.3.2:
1113 * o It turns any WQE into a signalled WQE.
1114 * o Local catastrophic error must be surfaced
1115 * o QP must be moved into Terminate state: done by code
1116 * doing socket state change processing
1117 *
1118 * o TODO: Termination message must be sent.
1119 * o TODO: Implement more precise work completion errors,
1120 * see enum ib_wc_status in ib_verbs.h
1121 */
1122 siw_dbg_qp(qp, "wqe type %d processing failed: %d\n",
1123 tx_type(wqe), rv);
1124
1125 spin_lock_irqsave(&qp->sq_lock, flags);
1126 /*
1127 * RREQ may have already been completed by inbound RRESP!
1128 */
1129 if ((tx_type == SIW_OP_READ ||
1130 tx_type == SIW_OP_READ_LOCAL_INV) && qp->attrs.orq_size) {
1131 /* Cleanup pending entry in ORQ */
1132 qp->orq_put--;
1133 qp->orq[qp->orq_put % qp->attrs.orq_size].flags = 0;
1134 }
1135 spin_unlock_irqrestore(&qp->sq_lock, flags);
1136 /*
1137 * immediately suspends further TX processing
1138 */
1139 if (!qp->tx_ctx.tx_suspend)
1140 siw_qp_cm_drop(qp, 0);
1141
1142 switch (tx_type) {
1143 case SIW_OP_SEND:
1144 case SIW_OP_SEND_REMOTE_INV:
1145 case SIW_OP_SEND_WITH_IMM:
1146 case SIW_OP_WRITE:
1147 case SIW_OP_READ:
1148 case SIW_OP_READ_LOCAL_INV:
1149 siw_wqe_put_mem(wqe, tx_type);
1150 fallthrough;
1151
1152 case SIW_OP_INVAL_STAG:
1153 case SIW_OP_REG_MR:
1154 siw_sqe_complete(qp, &wqe->sqe, wqe->bytes,
1155 SIW_WC_LOC_QP_OP_ERR);
1156
1157 siw_qp_event(qp, IB_EVENT_QP_FATAL);
1158
1159 break;
1160
1161 case SIW_OP_READ_RESPONSE:
1162 siw_dbg_qp(qp, "proc. read.response failed: %d\n", rv);
1163
1164 siw_qp_event(qp, IB_EVENT_QP_REQ_ERR);
1165
1166 siw_wqe_put_mem(wqe, SIW_OP_READ_RESPONSE);
1167
1168 break;
1169
1170 default:
1171 WARN(1, "undefined WQE type %d\n", tx_type);
1172 rv = -EINVAL;
1173 }
1174 wqe->wr_status = SIW_WR_IDLE;
1175 }
1176 done:
1177 return rv;
1178 }
1179
siw_sq_resume(struct siw_qp * qp)1180 static void siw_sq_resume(struct siw_qp *qp)
1181 {
1182 if (down_read_trylock(&qp->state_lock)) {
1183 if (likely(qp->attrs.state == SIW_QP_STATE_RTS &&
1184 !qp->tx_ctx.tx_suspend)) {
1185 int rv = siw_qp_sq_process(qp);
1186
1187 up_read(&qp->state_lock);
1188
1189 if (unlikely(rv < 0)) {
1190 siw_dbg_qp(qp, "SQ task failed: err %d\n", rv);
1191
1192 if (!qp->tx_ctx.tx_suspend)
1193 siw_qp_cm_drop(qp, 0);
1194 }
1195 } else {
1196 up_read(&qp->state_lock);
1197 }
1198 } else {
1199 siw_dbg_qp(qp, "Resume SQ while QP locked\n");
1200 }
1201 siw_qp_put(qp);
1202 }
1203
1204 struct tx_task_t {
1205 struct llist_head active;
1206 wait_queue_head_t waiting;
1207 };
1208
1209 static DEFINE_PER_CPU(struct tx_task_t, siw_tx_task_g);
1210
siw_create_tx_threads(void)1211 int siw_create_tx_threads(void)
1212 {
1213 int cpu, assigned = 0;
1214
1215 for_each_online_cpu(cpu) {
1216 struct tx_task_t *tx_task;
1217
1218 /* Skip HT cores */
1219 if (cpu % cpumask_weight(topology_sibling_cpumask(cpu)))
1220 continue;
1221
1222 tx_task = &per_cpu(siw_tx_task_g, cpu);
1223 init_llist_head(&tx_task->active);
1224 init_waitqueue_head(&tx_task->waiting);
1225
1226 siw_tx_thread[cpu] =
1227 kthread_run_on_cpu(siw_run_sq,
1228 (unsigned long *)(long)cpu,
1229 cpu, "siw_tx/%u");
1230 if (IS_ERR(siw_tx_thread[cpu])) {
1231 siw_tx_thread[cpu] = NULL;
1232 continue;
1233 }
1234 assigned++;
1235 }
1236 return assigned;
1237 }
1238
siw_stop_tx_threads(void)1239 void siw_stop_tx_threads(void)
1240 {
1241 int cpu;
1242
1243 for_each_possible_cpu(cpu) {
1244 if (siw_tx_thread[cpu]) {
1245 kthread_stop(siw_tx_thread[cpu]);
1246 wake_up(&per_cpu(siw_tx_task_g, cpu).waiting);
1247 siw_tx_thread[cpu] = NULL;
1248 }
1249 }
1250 }
1251
siw_run_sq(void * data)1252 int siw_run_sq(void *data)
1253 {
1254 const int nr_cpu = (unsigned int)(long)data;
1255 struct llist_node *active;
1256 struct siw_qp *qp;
1257 struct tx_task_t *tx_task = &per_cpu(siw_tx_task_g, nr_cpu);
1258
1259 while (1) {
1260 struct llist_node *fifo_list = NULL;
1261
1262 wait_event_interruptible(tx_task->waiting,
1263 !llist_empty(&tx_task->active) ||
1264 kthread_should_stop());
1265
1266 if (kthread_should_stop())
1267 break;
1268
1269 active = llist_del_all(&tx_task->active);
1270 /*
1271 * llist_del_all returns a list with newest entry first.
1272 * Re-order list for fairness among QP's.
1273 */
1274 fifo_list = llist_reverse_order(active);
1275 while (fifo_list) {
1276 qp = container_of(fifo_list, struct siw_qp, tx_list);
1277 fifo_list = llist_next(fifo_list);
1278 qp->tx_list.next = NULL;
1279
1280 siw_sq_resume(qp);
1281 }
1282 }
1283 active = llist_del_all(&tx_task->active);
1284 if (active) {
1285 llist_for_each_entry(qp, active, tx_list) {
1286 qp->tx_list.next = NULL;
1287 siw_sq_resume(qp);
1288 }
1289 }
1290 return 0;
1291 }
1292
siw_sq_start(struct siw_qp * qp)1293 int siw_sq_start(struct siw_qp *qp)
1294 {
1295 if (tx_wqe(qp)->wr_status == SIW_WR_IDLE)
1296 return 0;
1297
1298 if (unlikely(!cpu_online(qp->tx_cpu))) {
1299 siw_put_tx_cpu(qp->tx_cpu);
1300 qp->tx_cpu = siw_get_tx_cpu(qp->sdev);
1301 if (qp->tx_cpu < 0) {
1302 pr_warn("siw: no tx cpu available\n");
1303
1304 return -EIO;
1305 }
1306 }
1307 siw_qp_get(qp);
1308
1309 llist_add(&qp->tx_list, &per_cpu(siw_tx_task_g, qp->tx_cpu).active);
1310
1311 wake_up(&per_cpu(siw_tx_task_g, qp->tx_cpu).waiting);
1312
1313 return 0;
1314 }
1315