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