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