xref: /linux/drivers/infiniband/sw/siw/siw_qp_rx.c (revision dd91b5e1d6448794c07378d1be12e3261c8769e7)
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 
12 #include <rdma/iw_cm.h>
13 #include <rdma/ib_verbs.h>
14 
15 #include "siw.h"
16 #include "siw_verbs.h"
17 #include "siw_mem.h"
18 
19 /*
20  * siw_rx_umem()
21  *
22  * Receive data of @len into target referenced by @dest_addr.
23  *
24  * @srx:	Receive Context
25  * @umem:	siw representation of target memory
26  * @dest_addr:	user virtual address
27  * @len:	number of bytes to place
28  */
siw_rx_umem(struct siw_rx_stream * srx,struct siw_umem * umem,u64 dest_addr,int len)29 static int siw_rx_umem(struct siw_rx_stream *srx, struct siw_umem *umem,
30 		       u64 dest_addr, int len)
31 {
32 	int copied = 0;
33 
34 	while (len) {
35 		struct page *p;
36 		int pg_off, bytes, rv;
37 		void *dest;
38 
39 		p = siw_get_upage(umem, dest_addr);
40 		if (unlikely(!p)) {
41 			pr_warn("siw: %s: [QP %u]: bogus addr: %p, %p\n",
42 				__func__, qp_id(rx_qp(srx)),
43 				(void *)(uintptr_t)dest_addr,
44 				(void *)(uintptr_t)umem->fp_addr);
45 			/* siw internal error */
46 			srx->skb_copied += copied;
47 			srx->skb_new -= copied;
48 
49 			return -EFAULT;
50 		}
51 		pg_off = dest_addr & ~PAGE_MASK;
52 		bytes = min(len, (int)PAGE_SIZE - pg_off);
53 
54 		siw_dbg_qp(rx_qp(srx), "page %p, bytes=%u\n", p, bytes);
55 
56 		dest = kmap_atomic(p);
57 		rv = skb_copy_bits(srx->skb, srx->skb_offset, dest + pg_off,
58 				   bytes);
59 
60 		if (unlikely(rv)) {
61 			kunmap_atomic(dest);
62 			srx->skb_copied += copied;
63 			srx->skb_new -= copied;
64 
65 			pr_warn("siw: [QP %u]: %s, len %d, page %p, rv %d\n",
66 				qp_id(rx_qp(srx)), __func__, len, p, rv);
67 
68 			return -EFAULT;
69 		}
70 		if (srx->mpa_crc_enabled) {
71 			if (rdma_is_kernel_res(&rx_qp(srx)->base_qp.res)) {
72 				siw_crc_update(&srx->mpa_crc, dest + pg_off,
73 					       bytes);
74 				kunmap_atomic(dest);
75 			} else {
76 				kunmap_atomic(dest);
77 				/*
78 				 * Do CRC on original, not target buffer.
79 				 * Some user land applications may
80 				 * concurrently write the target buffer,
81 				 * which would yield a broken CRC.
82 				 * Walking the skb twice is very ineffcient.
83 				 * Folding the CRC into skb_copy_bits()
84 				 * would be much better, but is currently
85 				 * not supported.
86 				 */
87 				siw_crc_skb(srx, bytes);
88 			}
89 		} else {
90 			kunmap_atomic(dest);
91 		}
92 		srx->skb_offset += bytes;
93 		copied += bytes;
94 		len -= bytes;
95 		dest_addr += bytes;
96 		pg_off = 0;
97 	}
98 	srx->skb_copied += copied;
99 	srx->skb_new -= copied;
100 
101 	return copied;
102 }
103 
siw_rx_kva(struct siw_rx_stream * srx,void * kva,int len)104 static int siw_rx_kva(struct siw_rx_stream *srx, void *kva, int len)
105 {
106 	int rv;
107 
108 	siw_dbg_qp(rx_qp(srx), "kva: 0x%p, len: %u\n", kva, len);
109 
110 	rv = skb_copy_bits(srx->skb, srx->skb_offset, kva, len);
111 	if (unlikely(rv)) {
112 		pr_warn("siw: [QP %u]: %s, len %d, kva 0x%p, rv %d\n",
113 			qp_id(rx_qp(srx)), __func__, len, kva, rv);
114 
115 		return rv;
116 	}
117 	if (srx->mpa_crc_enabled)
118 		siw_crc_update(&srx->mpa_crc, kva, len);
119 
120 	srx->skb_offset += len;
121 	srx->skb_copied += len;
122 	srx->skb_new -= len;
123 
124 	return len;
125 }
126 
siw_rx_pbl(struct siw_rx_stream * srx,int * pbl_idx,struct siw_mem * mem,u64 addr,int len)127 static int siw_rx_pbl(struct siw_rx_stream *srx, int *pbl_idx,
128 		      struct siw_mem *mem, u64 addr, int len)
129 {
130 	struct siw_pbl *pbl = mem->pbl;
131 	u64 offset = addr - mem->va;
132 	int copied = 0;
133 
134 	while (len) {
135 		int bytes;
136 		dma_addr_t buf_addr =
137 			siw_pbl_get_buffer(pbl, offset, &bytes, pbl_idx);
138 		if (!buf_addr)
139 			break;
140 
141 		bytes = min(bytes, len);
142 		if (siw_rx_kva(srx, ib_virt_dma_to_ptr(buf_addr), bytes) ==
143 		    bytes) {
144 			copied += bytes;
145 			offset += bytes;
146 			len -= bytes;
147 		} else {
148 			break;
149 		}
150 	}
151 	return copied;
152 }
153 
154 /*
155  * siw_rresp_check_ntoh()
156  *
157  * Check incoming RRESP fragment header against expected
158  * header values and update expected values for potential next
159  * fragment.
160  *
161  * NOTE: This function must be called only if a RRESP DDP segment
162  *       starts but not for fragmented consecutive pieces of an
163  *       already started DDP segment.
164  */
siw_rresp_check_ntoh(struct siw_rx_stream * srx,struct siw_rx_fpdu * frx)165 static int siw_rresp_check_ntoh(struct siw_rx_stream *srx,
166 				struct siw_rx_fpdu *frx)
167 {
168 	struct iwarp_rdma_rresp *rresp = &srx->hdr.rresp;
169 	struct siw_wqe *wqe = &frx->wqe_active;
170 	enum ddp_ecode ecode;
171 
172 	u32 sink_stag = be32_to_cpu(rresp->sink_stag);
173 	u64 sink_to = be64_to_cpu(rresp->sink_to);
174 
175 	if (frx->first_ddp_seg) {
176 		srx->ddp_stag = wqe->sqe.sge[0].lkey;
177 		srx->ddp_to = wqe->sqe.sge[0].laddr;
178 		frx->pbl_idx = 0;
179 	}
180 	/* Below checks extend beyond the semantics of DDP, and
181 	 * into RDMAP:
182 	 * We check if the read response matches exactly the
183 	 * read request which was send to the remote peer to
184 	 * trigger this read response. RFC5040/5041 do not
185 	 * always have a proper error code for the detected
186 	 * error cases. We choose 'base or bounds error' for
187 	 * cases where the inbound STag is valid, but offset
188 	 * or length do not match our response receive state.
189 	 */
190 	if (unlikely(srx->ddp_stag != sink_stag)) {
191 		pr_warn("siw: [QP %u]: rresp stag: %08x != %08x\n",
192 			qp_id(rx_qp(srx)), sink_stag, srx->ddp_stag);
193 		ecode = DDP_ECODE_T_INVALID_STAG;
194 		goto error;
195 	}
196 	if (unlikely(srx->ddp_to != sink_to)) {
197 		pr_warn("siw: [QP %u]: rresp off: %016llx != %016llx\n",
198 			qp_id(rx_qp(srx)), (unsigned long long)sink_to,
199 			(unsigned long long)srx->ddp_to);
200 		ecode = DDP_ECODE_T_BASE_BOUNDS;
201 		goto error;
202 	}
203 	if (unlikely(!frx->more_ddp_segs &&
204 		     (wqe->processed + srx->fpdu_part_rem != wqe->bytes))) {
205 		pr_warn("siw: [QP %u]: rresp len: %d != %d\n",
206 			qp_id(rx_qp(srx)),
207 			wqe->processed + srx->fpdu_part_rem, wqe->bytes);
208 		ecode = DDP_ECODE_T_BASE_BOUNDS;
209 		goto error;
210 	}
211 	return 0;
212 error:
213 	siw_init_terminate(rx_qp(srx), TERM_ERROR_LAYER_DDP,
214 			   DDP_ETYPE_TAGGED_BUF, ecode, 0);
215 	return -EINVAL;
216 }
217 
218 /*
219  * siw_write_check_ntoh()
220  *
221  * Check incoming WRITE fragment header against expected
222  * header values and update expected values for potential next
223  * fragment
224  *
225  * NOTE: This function must be called only if a WRITE DDP segment
226  *       starts but not for fragmented consecutive pieces of an
227  *       already started DDP segment.
228  */
siw_write_check_ntoh(struct siw_rx_stream * srx,struct siw_rx_fpdu * frx)229 static int siw_write_check_ntoh(struct siw_rx_stream *srx,
230 				struct siw_rx_fpdu *frx)
231 {
232 	struct iwarp_rdma_write *write = &srx->hdr.rwrite;
233 	enum ddp_ecode ecode;
234 
235 	u32 sink_stag = be32_to_cpu(write->sink_stag);
236 	u64 sink_to = be64_to_cpu(write->sink_to);
237 
238 	if (frx->first_ddp_seg) {
239 		srx->ddp_stag = sink_stag;
240 		srx->ddp_to = sink_to;
241 		frx->pbl_idx = 0;
242 	} else {
243 		if (unlikely(srx->ddp_stag != sink_stag)) {
244 			pr_warn("siw: [QP %u]: write stag: %08x != %08x\n",
245 				qp_id(rx_qp(srx)), sink_stag,
246 				srx->ddp_stag);
247 			ecode = DDP_ECODE_T_INVALID_STAG;
248 			goto error;
249 		}
250 		if (unlikely(srx->ddp_to != sink_to)) {
251 			pr_warn("siw: [QP %u]: write off: %016llx != %016llx\n",
252 				qp_id(rx_qp(srx)),
253 				(unsigned long long)sink_to,
254 				(unsigned long long)srx->ddp_to);
255 			ecode = DDP_ECODE_T_BASE_BOUNDS;
256 			goto error;
257 		}
258 	}
259 	return 0;
260 error:
261 	siw_init_terminate(rx_qp(srx), TERM_ERROR_LAYER_DDP,
262 			   DDP_ETYPE_TAGGED_BUF, ecode, 0);
263 	return -EINVAL;
264 }
265 
266 /*
267  * siw_send_check_ntoh()
268  *
269  * Check incoming SEND fragment header against expected
270  * header values and update expected MSN if no next
271  * fragment expected
272  *
273  * NOTE: This function must be called only if a SEND DDP segment
274  *       starts but not for fragmented consecutive pieces of an
275  *       already started DDP segment.
276  */
siw_send_check_ntoh(struct siw_rx_stream * srx,struct siw_rx_fpdu * frx)277 static int siw_send_check_ntoh(struct siw_rx_stream *srx,
278 			       struct siw_rx_fpdu *frx)
279 {
280 	struct iwarp_send_inv *send = &srx->hdr.send_inv;
281 	struct siw_wqe *wqe = &frx->wqe_active;
282 	enum ddp_ecode ecode;
283 
284 	u32 ddp_msn = be32_to_cpu(send->ddp_msn);
285 	u32 ddp_mo = be32_to_cpu(send->ddp_mo);
286 	u32 ddp_qn = be32_to_cpu(send->ddp_qn);
287 
288 	if (unlikely(ddp_qn != RDMAP_UNTAGGED_QN_SEND)) {
289 		pr_warn("siw: [QP %u]: invalid ddp qn %d for send\n",
290 			qp_id(rx_qp(srx)), ddp_qn);
291 		ecode = DDP_ECODE_UT_INVALID_QN;
292 		goto error;
293 	}
294 	if (unlikely(ddp_msn != srx->ddp_msn[RDMAP_UNTAGGED_QN_SEND])) {
295 		pr_warn("siw: [QP %u]: send msn: %u != %u\n",
296 			qp_id(rx_qp(srx)), ddp_msn,
297 			srx->ddp_msn[RDMAP_UNTAGGED_QN_SEND]);
298 		ecode = DDP_ECODE_UT_INVALID_MSN_RANGE;
299 		goto error;
300 	}
301 	if (unlikely(ddp_mo != wqe->processed)) {
302 		pr_warn("siw: [QP %u], send mo: %u != %u\n",
303 			qp_id(rx_qp(srx)), ddp_mo, wqe->processed);
304 		ecode = DDP_ECODE_UT_INVALID_MO;
305 		goto error;
306 	}
307 	if (frx->first_ddp_seg) {
308 		/* initialize user memory write position */
309 		frx->sge_idx = 0;
310 		frx->sge_off = 0;
311 		frx->pbl_idx = 0;
312 
313 		/* only valid for SEND_INV and SEND_SE_INV operations */
314 		srx->inval_stag = be32_to_cpu(send->inval_stag);
315 	}
316 	if (unlikely(wqe->bytes < wqe->processed + srx->fpdu_part_rem)) {
317 		siw_dbg_qp(rx_qp(srx), "receive space short: %d - %d < %d\n",
318 			   wqe->bytes, wqe->processed, srx->fpdu_part_rem);
319 		wqe->wc_status = SIW_WC_LOC_LEN_ERR;
320 		ecode = DDP_ECODE_UT_INVALID_MSN_NOBUF;
321 		goto error;
322 	}
323 	return 0;
324 error:
325 	siw_init_terminate(rx_qp(srx), TERM_ERROR_LAYER_DDP,
326 			   DDP_ETYPE_UNTAGGED_BUF, ecode, 0);
327 	return -EINVAL;
328 }
329 
siw_rqe_get(struct siw_qp * qp)330 static struct siw_wqe *siw_rqe_get(struct siw_qp *qp)
331 {
332 	struct siw_rqe *rqe;
333 	struct siw_srq *srq;
334 	struct siw_wqe *wqe = NULL;
335 	bool srq_event = false;
336 	unsigned long flags;
337 
338 	srq = qp->srq;
339 	if (srq) {
340 		spin_lock_irqsave(&srq->lock, flags);
341 		if (unlikely(!srq->num_rqe))
342 			goto out;
343 
344 		rqe = &srq->recvq[srq->rq_get % srq->num_rqe];
345 	} else {
346 		if (unlikely(!qp->recvq))
347 			goto out;
348 
349 		rqe = &qp->recvq[qp->rq_get % qp->attrs.rq_size];
350 	}
351 	if (likely(rqe->flags == SIW_WQE_VALID)) {
352 		int num_sge = rqe->num_sge;
353 
354 		if (likely(num_sge <= SIW_MAX_SGE)) {
355 			int i = 0;
356 
357 			wqe = rx_wqe(&qp->rx_untagged);
358 			rx_type(wqe) = SIW_OP_RECEIVE;
359 			wqe->wr_status = SIW_WR_INPROGRESS;
360 			wqe->bytes = 0;
361 			wqe->processed = 0;
362 
363 			wqe->rqe.id = rqe->id;
364 			wqe->rqe.num_sge = num_sge;
365 
366 			while (i < num_sge) {
367 				wqe->rqe.sge[i].laddr = rqe->sge[i].laddr;
368 				wqe->rqe.sge[i].lkey = rqe->sge[i].lkey;
369 				wqe->rqe.sge[i].length = rqe->sge[i].length;
370 				wqe->bytes += wqe->rqe.sge[i].length;
371 				wqe->mem[i] = NULL;
372 				i++;
373 			}
374 			/* can be re-used by appl */
375 			smp_store_mb(rqe->flags, 0);
376 		} else {
377 			siw_dbg_qp(qp, "too many sge's: %d\n", rqe->num_sge);
378 			if (srq)
379 				spin_unlock_irqrestore(&srq->lock, flags);
380 			return NULL;
381 		}
382 		if (!srq) {
383 			qp->rq_get++;
384 		} else {
385 			if (srq->armed) {
386 				/* Test SRQ limit */
387 				u32 off = (srq->rq_get + srq->limit) %
388 					  srq->num_rqe;
389 				struct siw_rqe *rqe2 = &srq->recvq[off];
390 
391 				if (!(rqe2->flags & SIW_WQE_VALID)) {
392 					srq->armed = false;
393 					srq_event = true;
394 				}
395 			}
396 			srq->rq_get++;
397 		}
398 	}
399 out:
400 	if (srq) {
401 		spin_unlock_irqrestore(&srq->lock, flags);
402 		if (srq_event)
403 			siw_srq_event(srq, IB_EVENT_SRQ_LIMIT_REACHED);
404 	}
405 	return wqe;
406 }
407 
siw_rx_data(struct siw_mem * mem_p,struct siw_rx_stream * srx,unsigned int * pbl_idx,u64 addr,int bytes)408 static int siw_rx_data(struct siw_mem *mem_p, struct siw_rx_stream *srx,
409 		       unsigned int *pbl_idx, u64 addr, int bytes)
410 {
411 	int rv;
412 
413 	if (mem_p->mem_obj == NULL)
414 		rv = siw_rx_kva(srx, ib_virt_dma_to_ptr(addr), bytes);
415 	else if (!mem_p->is_pbl)
416 		rv = siw_rx_umem(srx, mem_p->umem, addr, bytes);
417 	else
418 		rv = siw_rx_pbl(srx, pbl_idx, mem_p, addr, bytes);
419 	return rv;
420 }
421 
422 /*
423  * siw_proc_send:
424  *
425  * Process one incoming SEND and place data into memory referenced by
426  * receive wqe.
427  *
428  * Function supports partially received sends (suspending/resuming
429  * current receive wqe processing)
430  *
431  * return value:
432  *	0:       reached the end of a DDP segment
433  *	-EAGAIN: to be called again to finish the DDP segment
434  */
siw_proc_send(struct siw_qp * qp)435 int siw_proc_send(struct siw_qp *qp)
436 {
437 	struct siw_rx_stream *srx = &qp->rx_stream;
438 	struct siw_rx_fpdu *frx = &qp->rx_untagged;
439 	struct siw_wqe *wqe;
440 	u32 data_bytes; /* all data bytes available */
441 	u32 rcvd_bytes; /* sum of data bytes rcvd */
442 	int rv = 0;
443 
444 	if (frx->first_ddp_seg) {
445 		wqe = siw_rqe_get(qp);
446 		if (unlikely(!wqe)) {
447 			siw_init_terminate(qp, TERM_ERROR_LAYER_DDP,
448 					   DDP_ETYPE_UNTAGGED_BUF,
449 					   DDP_ECODE_UT_INVALID_MSN_NOBUF, 0);
450 			return -ENOENT;
451 		}
452 	} else {
453 		wqe = rx_wqe(frx);
454 	}
455 	if (srx->state == SIW_GET_DATA_START) {
456 		rv = siw_send_check_ntoh(srx, frx);
457 		if (unlikely(rv)) {
458 			siw_qp_event(qp, IB_EVENT_QP_FATAL);
459 			return rv;
460 		}
461 		if (!srx->fpdu_part_rem) /* zero length SEND */
462 			return 0;
463 	}
464 	data_bytes = min(srx->fpdu_part_rem, srx->skb_new);
465 	rcvd_bytes = 0;
466 
467 	/* A zero length SEND will skip below loop */
468 	while (data_bytes) {
469 		struct ib_pd *pd;
470 		struct siw_mem **mem, *mem_p;
471 		struct siw_sge *sge;
472 		u32 sge_bytes; /* data bytes avail for SGE */
473 
474 		sge = &wqe->rqe.sge[frx->sge_idx];
475 
476 		if (!sge->length) {
477 			/* just skip empty sge's */
478 			frx->sge_idx++;
479 			frx->sge_off = 0;
480 			frx->pbl_idx = 0;
481 			continue;
482 		}
483 		sge_bytes = min(data_bytes, sge->length - frx->sge_off);
484 		mem = &wqe->mem[frx->sge_idx];
485 
486 		/*
487 		 * check with QP's PD if no SRQ present, SRQ's PD otherwise
488 		 */
489 		pd = qp->srq == NULL ? qp->pd : qp->srq->base_srq.pd;
490 
491 		rv = siw_check_sge(pd, sge, mem, IB_ACCESS_LOCAL_WRITE,
492 				   frx->sge_off, sge_bytes);
493 		if (unlikely(rv)) {
494 			siw_init_terminate(qp, TERM_ERROR_LAYER_DDP,
495 					   DDP_ETYPE_CATASTROPHIC,
496 					   DDP_ECODE_CATASTROPHIC, 0);
497 
498 			siw_qp_event(qp, IB_EVENT_QP_ACCESS_ERR);
499 			break;
500 		}
501 		mem_p = *mem;
502 		rv = siw_rx_data(mem_p, srx, &frx->pbl_idx,
503 				 sge->laddr + frx->sge_off, sge_bytes);
504 		if (unlikely(rv != sge_bytes)) {
505 			wqe->processed += rcvd_bytes;
506 
507 			siw_init_terminate(qp, TERM_ERROR_LAYER_DDP,
508 					   DDP_ETYPE_CATASTROPHIC,
509 					   DDP_ECODE_CATASTROPHIC, 0);
510 			return -EINVAL;
511 		}
512 		frx->sge_off += rv;
513 
514 		if (frx->sge_off == sge->length) {
515 			frx->sge_idx++;
516 			frx->sge_off = 0;
517 			frx->pbl_idx = 0;
518 		}
519 		data_bytes -= rv;
520 		rcvd_bytes += rv;
521 
522 		srx->fpdu_part_rem -= rv;
523 		srx->fpdu_part_rcvd += rv;
524 	}
525 	wqe->processed += rcvd_bytes;
526 
527 	if (!srx->fpdu_part_rem)
528 		return 0;
529 
530 	return (rv < 0) ? rv : -EAGAIN;
531 }
532 
533 /*
534  * siw_proc_write:
535  *
536  * Place incoming WRITE after referencing and checking target buffer
537 
538  * Function supports partially received WRITEs (suspending/resuming
539  * current receive processing)
540  *
541  * return value:
542  *	0:       reached the end of a DDP segment
543  *	-EAGAIN: to be called again to finish the DDP segment
544  */
siw_proc_write(struct siw_qp * qp)545 int siw_proc_write(struct siw_qp *qp)
546 {
547 	struct siw_rx_stream *srx = &qp->rx_stream;
548 	struct siw_rx_fpdu *frx = &qp->rx_tagged;
549 	struct siw_mem *mem;
550 	int bytes, rv;
551 
552 	if (srx->state == SIW_GET_DATA_START) {
553 		if (!srx->fpdu_part_rem) /* zero length WRITE */
554 			return 0;
555 
556 		rv = siw_write_check_ntoh(srx, frx);
557 		if (unlikely(rv)) {
558 			siw_qp_event(qp, IB_EVENT_QP_FATAL);
559 			return rv;
560 		}
561 	}
562 	bytes = min(srx->fpdu_part_rem, srx->skb_new);
563 
564 	if (frx->first_ddp_seg) {
565 		struct siw_wqe *wqe = rx_wqe(frx);
566 
567 		rx_mem(frx) = siw_mem_id2obj(qp->sdev, srx->ddp_stag >> 8);
568 		if (unlikely(!rx_mem(frx))) {
569 			siw_dbg_qp(qp,
570 				   "sink stag not found/invalid, stag 0x%08x\n",
571 				   srx->ddp_stag);
572 
573 			siw_init_terminate(qp, TERM_ERROR_LAYER_DDP,
574 					   DDP_ETYPE_TAGGED_BUF,
575 					   DDP_ECODE_T_INVALID_STAG, 0);
576 			return -EINVAL;
577 		}
578 		wqe->rqe.num_sge = 1;
579 		rx_type(wqe) = SIW_OP_WRITE;
580 		wqe->wr_status = SIW_WR_INPROGRESS;
581 	}
582 	mem = rx_mem(frx);
583 
584 	/*
585 	 * Check if application re-registered memory with different
586 	 * key field of STag.
587 	 */
588 	if (unlikely(mem->stag != srx->ddp_stag)) {
589 		siw_init_terminate(qp, TERM_ERROR_LAYER_DDP,
590 				   DDP_ETYPE_TAGGED_BUF,
591 				   DDP_ECODE_T_INVALID_STAG, 0);
592 		return -EINVAL;
593 	}
594 	rv = siw_check_mem(qp->pd, mem, srx->ddp_to + srx->fpdu_part_rcvd,
595 			   IB_ACCESS_REMOTE_WRITE, bytes);
596 	if (unlikely(rv)) {
597 		siw_init_terminate(qp, TERM_ERROR_LAYER_DDP,
598 				   DDP_ETYPE_TAGGED_BUF, siw_tagged_error(-rv),
599 				   0);
600 
601 		siw_qp_event(qp, IB_EVENT_QP_ACCESS_ERR);
602 
603 		return -EINVAL;
604 	}
605 
606 	rv = siw_rx_data(mem, srx, &frx->pbl_idx,
607 			 srx->ddp_to + srx->fpdu_part_rcvd, bytes);
608 	if (unlikely(rv != bytes)) {
609 		siw_init_terminate(qp, TERM_ERROR_LAYER_DDP,
610 				   DDP_ETYPE_CATASTROPHIC,
611 				   DDP_ECODE_CATASTROPHIC, 0);
612 		return -EINVAL;
613 	}
614 	srx->fpdu_part_rem -= rv;
615 	srx->fpdu_part_rcvd += rv;
616 
617 	if (!srx->fpdu_part_rem) {
618 		srx->ddp_to += srx->fpdu_part_rcvd;
619 		return 0;
620 	}
621 	return -EAGAIN;
622 }
623 
624 /*
625  * Inbound RREQ's cannot carry user data.
626  */
siw_proc_rreq(struct siw_qp * qp)627 int siw_proc_rreq(struct siw_qp *qp)
628 {
629 	struct siw_rx_stream *srx = &qp->rx_stream;
630 
631 	if (!srx->fpdu_part_rem)
632 		return 0;
633 
634 	pr_warn("siw: [QP %u]: rreq with mpa len %d\n", qp_id(qp),
635 		be16_to_cpu(srx->hdr.ctrl.mpa_len));
636 
637 	return -EPROTO;
638 }
639 
640 /*
641  * siw_init_rresp:
642  *
643  * Process inbound RDMA READ REQ. Produce a pseudo READ RESPONSE WQE.
644  * Put it at the tail of the IRQ, if there is another WQE currently in
645  * transmit processing. If not, make it the current WQE to be processed
646  * and schedule transmit processing.
647  *
648  * Can be called from softirq context and from process
649  * context (RREAD socket loopback case!)
650  *
651  * return value:
652  *	0:      success,
653  *		failure code otherwise
654  */
655 
siw_init_rresp(struct siw_qp * qp,struct siw_rx_stream * srx)656 static int siw_init_rresp(struct siw_qp *qp, struct siw_rx_stream *srx)
657 {
658 	struct siw_wqe *tx_work = tx_wqe(qp);
659 	struct siw_sqe *resp;
660 
661 	uint64_t raddr = be64_to_cpu(srx->hdr.rreq.sink_to),
662 		 laddr = be64_to_cpu(srx->hdr.rreq.source_to);
663 	uint32_t length = be32_to_cpu(srx->hdr.rreq.read_size),
664 		 lkey = be32_to_cpu(srx->hdr.rreq.source_stag),
665 		 rkey = be32_to_cpu(srx->hdr.rreq.sink_stag),
666 		 msn = be32_to_cpu(srx->hdr.rreq.ddp_msn);
667 
668 	int run_sq = 1, rv = 0;
669 	unsigned long flags;
670 
671 	if (unlikely(msn != srx->ddp_msn[RDMAP_UNTAGGED_QN_RDMA_READ])) {
672 		siw_init_terminate(qp, TERM_ERROR_LAYER_DDP,
673 				   DDP_ETYPE_UNTAGGED_BUF,
674 				   DDP_ECODE_UT_INVALID_MSN_RANGE, 0);
675 		return -EPROTO;
676 	}
677 	spin_lock_irqsave(&qp->sq_lock, flags);
678 
679 	if (unlikely(!qp->attrs.irq_size)) {
680 		run_sq = 0;
681 		goto error_irq;
682 	}
683 	if (tx_work->wr_status == SIW_WR_IDLE) {
684 		/*
685 		 * immediately schedule READ response w/o
686 		 * consuming IRQ entry: IRQ must be empty.
687 		 */
688 		tx_work->processed = 0;
689 		tx_work->mem[0] = NULL;
690 		tx_work->wr_status = SIW_WR_QUEUED;
691 		resp = &tx_work->sqe;
692 	} else {
693 		resp = irq_alloc_free(qp);
694 		run_sq = 0;
695 	}
696 	if (likely(resp)) {
697 		resp->opcode = SIW_OP_READ_RESPONSE;
698 
699 		resp->sge[0].length = length;
700 		resp->sge[0].laddr = laddr;
701 		resp->sge[0].lkey = lkey;
702 
703 		/* Keep aside message sequence number for potential
704 		 * error reporting during Read Response generation.
705 		 */
706 		resp->sge[1].length = msn;
707 
708 		resp->raddr = raddr;
709 		resp->rkey = rkey;
710 		resp->num_sge = length ? 1 : 0;
711 
712 		/* RRESP now valid as current TX wqe or placed into IRQ */
713 		smp_store_mb(resp->flags, SIW_WQE_VALID);
714 	} else {
715 error_irq:
716 		pr_warn("siw: [QP %u]: IRQ exceeded or null, size %d\n",
717 			qp_id(qp), qp->attrs.irq_size);
718 
719 		siw_init_terminate(qp, TERM_ERROR_LAYER_RDMAP,
720 				   RDMAP_ETYPE_REMOTE_OPERATION,
721 				   RDMAP_ECODE_CATASTROPHIC_STREAM, 0);
722 		rv = -EPROTO;
723 	}
724 
725 	spin_unlock_irqrestore(&qp->sq_lock, flags);
726 
727 	if (run_sq)
728 		rv = siw_sq_start(qp);
729 
730 	return rv;
731 }
732 
733 /*
734  * Only called at start of Read.Resonse processing.
735  * Transfer pending Read from tip of ORQ into currrent rx wqe,
736  * but keep ORQ entry valid until Read.Response processing done.
737  * No Queue locking needed.
738  */
siw_orqe_start_rx(struct siw_qp * qp)739 static int siw_orqe_start_rx(struct siw_qp *qp)
740 {
741 	struct siw_sqe *orqe;
742 	struct siw_wqe *wqe = NULL;
743 
744 	if (unlikely(!qp->attrs.orq_size))
745 		return -EPROTO;
746 
747 	/* make sure ORQ indices are current */
748 	smp_mb();
749 
750 	orqe = orq_get_current(qp);
751 	if (READ_ONCE(orqe->flags) & SIW_WQE_VALID) {
752 		/* RRESP is a TAGGED RDMAP operation */
753 		wqe = rx_wqe(&qp->rx_tagged);
754 		wqe->sqe.id = orqe->id;
755 		wqe->sqe.opcode = orqe->opcode;
756 		wqe->sqe.sge[0].laddr = orqe->sge[0].laddr;
757 		wqe->sqe.sge[0].lkey = orqe->sge[0].lkey;
758 		wqe->sqe.sge[0].length = orqe->sge[0].length;
759 		wqe->sqe.flags = orqe->flags;
760 		wqe->sqe.num_sge = 1;
761 		wqe->bytes = orqe->sge[0].length;
762 		wqe->processed = 0;
763 		wqe->mem[0] = NULL;
764 		/* make sure WQE is completely written before valid */
765 		smp_wmb();
766 		wqe->wr_status = SIW_WR_INPROGRESS;
767 
768 		return 0;
769 	}
770 	return -EPROTO;
771 }
772 
773 /*
774  * siw_proc_rresp:
775  *
776  * Place incoming RRESP data into memory referenced by RREQ WQE
777  * which is at the tip of the ORQ
778  *
779  * Function supports partially received RRESP's (suspending/resuming
780  * current receive processing)
781  */
siw_proc_rresp(struct siw_qp * qp)782 int siw_proc_rresp(struct siw_qp *qp)
783 {
784 	struct siw_rx_stream *srx = &qp->rx_stream;
785 	struct siw_rx_fpdu *frx = &qp->rx_tagged;
786 	struct siw_wqe *wqe = rx_wqe(frx);
787 	struct siw_mem **mem, *mem_p;
788 	struct siw_sge *sge;
789 	int bytes, rv;
790 
791 	if (frx->first_ddp_seg) {
792 		if (unlikely(wqe->wr_status != SIW_WR_IDLE)) {
793 			pr_warn("siw: [QP %u]: proc RRESP: status %d, op %d\n",
794 				qp_id(qp), wqe->wr_status, wqe->sqe.opcode);
795 			rv = -EPROTO;
796 			goto error_term;
797 		}
798 		/*
799 		 * fetch pending RREQ from orq
800 		 */
801 		rv = siw_orqe_start_rx(qp);
802 		if (rv) {
803 			pr_warn("siw: [QP %u]: ORQ empty, size %d\n",
804 				qp_id(qp), qp->attrs.orq_size);
805 			goto error_term;
806 		}
807 		rv = siw_rresp_check_ntoh(srx, frx);
808 		if (unlikely(rv)) {
809 			siw_qp_event(qp, IB_EVENT_QP_FATAL);
810 			return rv;
811 		}
812 	} else {
813 		if (unlikely(wqe->wr_status != SIW_WR_INPROGRESS)) {
814 			pr_warn("siw: [QP %u]: resume RRESP: status %d\n",
815 				qp_id(qp), wqe->wr_status);
816 			rv = -EPROTO;
817 			goto error_term;
818 		}
819 	}
820 	if (!srx->fpdu_part_rem) /* zero length RRESPONSE */
821 		return 0;
822 
823 	sge = wqe->sqe.sge; /* there is only one */
824 	mem = &wqe->mem[0];
825 
826 	if (!(*mem)) {
827 		/*
828 		 * check target memory which resolves memory on first fragment
829 		 */
830 		rv = siw_check_sge(qp->pd, sge, mem, IB_ACCESS_LOCAL_WRITE, 0,
831 				   wqe->bytes);
832 		if (unlikely(rv)) {
833 			siw_dbg_qp(qp, "target mem check: %d\n", rv);
834 			wqe->wc_status = SIW_WC_LOC_PROT_ERR;
835 
836 			siw_init_terminate(qp, TERM_ERROR_LAYER_DDP,
837 					   DDP_ETYPE_TAGGED_BUF,
838 					   siw_tagged_error(-rv), 0);
839 
840 			siw_qp_event(qp, IB_EVENT_QP_ACCESS_ERR);
841 
842 			return -EINVAL;
843 		}
844 	}
845 	mem_p = *mem;
846 
847 	bytes = min(srx->fpdu_part_rem, srx->skb_new);
848 	rv = siw_rx_data(mem_p, srx, &frx->pbl_idx,
849 			 sge->laddr + wqe->processed, bytes);
850 	if (rv != bytes) {
851 		wqe->wc_status = SIW_WC_GENERAL_ERR;
852 		rv = -EINVAL;
853 		goto error_term;
854 	}
855 	srx->fpdu_part_rem -= rv;
856 	srx->fpdu_part_rcvd += rv;
857 	wqe->processed += rv;
858 
859 	if (!srx->fpdu_part_rem) {
860 		srx->ddp_to += srx->fpdu_part_rcvd;
861 		return 0;
862 	}
863 	return -EAGAIN;
864 
865 error_term:
866 	siw_init_terminate(qp, TERM_ERROR_LAYER_DDP, DDP_ETYPE_CATASTROPHIC,
867 			   DDP_ECODE_CATASTROPHIC, 0);
868 	return rv;
869 }
870 
siw_update_skb_rcvd(struct siw_rx_stream * srx,u16 length)871 static void siw_update_skb_rcvd(struct siw_rx_stream *srx, u16 length)
872 {
873 	srx->skb_offset += length;
874 	srx->skb_new -= length;
875 	srx->skb_copied += length;
876 }
877 
siw_proc_terminate(struct siw_qp * qp)878 int siw_proc_terminate(struct siw_qp *qp)
879 {
880 	struct siw_rx_stream *srx = &qp->rx_stream;
881 	struct sk_buff *skb = srx->skb;
882 	struct iwarp_terminate *term = &srx->hdr.terminate;
883 	union iwarp_hdr term_info;
884 	u8 *infop = (u8 *)&term_info;
885 	enum rdma_opcode op;
886 	u16 to_copy = sizeof(struct iwarp_ctrl);
887 
888 	pr_warn("siw: got TERMINATE. layer %d, type %d, code %d\n",
889 		__rdmap_term_layer(term), __rdmap_term_etype(term),
890 		__rdmap_term_ecode(term));
891 
892 	if (be32_to_cpu(term->ddp_qn) != RDMAP_UNTAGGED_QN_TERMINATE ||
893 	    be32_to_cpu(term->ddp_msn) !=
894 		    qp->rx_stream.ddp_msn[RDMAP_UNTAGGED_QN_TERMINATE] ||
895 	    be32_to_cpu(term->ddp_mo) != 0) {
896 		pr_warn("siw: rx bogus TERM [QN x%08x, MSN x%08x, MO x%08x]\n",
897 			be32_to_cpu(term->ddp_qn), be32_to_cpu(term->ddp_msn),
898 			be32_to_cpu(term->ddp_mo));
899 		return -ECONNRESET;
900 	}
901 	/*
902 	 * Receive remaining pieces of TERM if indicated
903 	 */
904 	if (!term->flag_m)
905 		return -ECONNRESET;
906 
907 	/* Do not take the effort to reassemble a network fragmented
908 	 * TERM message
909 	 */
910 	if (srx->skb_new < sizeof(struct iwarp_ctrl_tagged))
911 		return -ECONNRESET;
912 
913 	memset(infop, 0, sizeof(term_info));
914 
915 	skb_copy_bits(skb, srx->skb_offset, infop, to_copy);
916 
917 	op = __rdmap_get_opcode(&term_info.ctrl);
918 	if (op >= RDMAP_TERMINATE)
919 		goto out;
920 
921 	infop += to_copy;
922 	siw_update_skb_rcvd(srx, to_copy);
923 	srx->fpdu_part_rcvd += to_copy;
924 	srx->fpdu_part_rem -= to_copy;
925 
926 	to_copy = iwarp_pktinfo[op].hdr_len - to_copy;
927 
928 	/* Again, no network fragmented TERM's */
929 	if (to_copy + MPA_CRC_SIZE > srx->skb_new)
930 		return -ECONNRESET;
931 
932 	skb_copy_bits(skb, srx->skb_offset, infop, to_copy);
933 
934 	if (term->flag_r) {
935 		siw_dbg_qp(qp, "TERM reports RDMAP hdr type %u, len %u (%s)\n",
936 			   op, be16_to_cpu(term_info.ctrl.mpa_len),
937 			   term->flag_m ? "valid" : "invalid");
938 	} else if (term->flag_d) {
939 		siw_dbg_qp(qp, "TERM reports DDP hdr type %u, len %u (%s)\n",
940 			   op, be16_to_cpu(term_info.ctrl.mpa_len),
941 			   term->flag_m ? "valid" : "invalid");
942 	}
943 out:
944 	siw_update_skb_rcvd(srx, to_copy);
945 	srx->fpdu_part_rcvd += to_copy;
946 	srx->fpdu_part_rem -= to_copy;
947 
948 	return -ECONNRESET;
949 }
950 
siw_get_trailer(struct siw_qp * qp,struct siw_rx_stream * srx)951 static int siw_get_trailer(struct siw_qp *qp, struct siw_rx_stream *srx)
952 {
953 	struct sk_buff *skb = srx->skb;
954 	int avail = min(srx->skb_new, srx->fpdu_part_rem);
955 	u8 *tbuf = (u8 *)&srx->trailer.crc - srx->pad;
956 	__wsum crc_in, crc_own = 0;
957 
958 	siw_dbg_qp(qp, "expected %d, available %d, pad %u\n",
959 		   srx->fpdu_part_rem, srx->skb_new, srx->pad);
960 
961 	skb_copy_bits(skb, srx->skb_offset, tbuf, avail);
962 
963 	siw_update_skb_rcvd(srx, avail);
964 	srx->fpdu_part_rem -= avail;
965 
966 	if (srx->fpdu_part_rem)
967 		return -EAGAIN;
968 
969 	if (!srx->mpa_crc_enabled)
970 		return 0;
971 
972 	if (srx->pad)
973 		siw_crc_update(&srx->mpa_crc, tbuf, srx->pad);
974 	/*
975 	 * CRC32 is computed, transmitted and received directly in NBO,
976 	 * so there's never a reason to convert byte order.
977 	 */
978 	siw_crc_final(&srx->mpa_crc, (u8 *)&crc_own);
979 	crc_in = (__force __wsum)srx->trailer.crc;
980 
981 	if (unlikely(crc_in != crc_own)) {
982 		pr_warn("siw: crc error. in: %08x, own %08x, op %u\n",
983 			crc_in, crc_own, qp->rx_stream.rdmap_op);
984 
985 		siw_init_terminate(qp, TERM_ERROR_LAYER_LLP,
986 				   LLP_ETYPE_MPA,
987 				   LLP_ECODE_RECEIVED_CRC, 0);
988 		return -EINVAL;
989 	}
990 	return 0;
991 }
992 
993 #define MIN_DDP_HDR sizeof(struct iwarp_ctrl_tagged)
994 
siw_get_hdr(struct siw_rx_stream * srx)995 static int siw_get_hdr(struct siw_rx_stream *srx)
996 {
997 	struct sk_buff *skb = srx->skb;
998 	struct siw_qp *qp = rx_qp(srx);
999 	struct iwarp_ctrl *c_hdr = &srx->hdr.ctrl;
1000 	struct siw_rx_fpdu *frx;
1001 	u8 opcode;
1002 	int bytes;
1003 
1004 	if (srx->fpdu_part_rcvd < MIN_DDP_HDR) {
1005 		/*
1006 		 * copy a mimimum sized (tagged) DDP frame control part
1007 		 */
1008 		bytes = min_t(int, srx->skb_new,
1009 			      MIN_DDP_HDR - srx->fpdu_part_rcvd);
1010 
1011 		skb_copy_bits(skb, srx->skb_offset,
1012 			      (char *)c_hdr + srx->fpdu_part_rcvd, bytes);
1013 
1014 		siw_update_skb_rcvd(srx, bytes);
1015 		srx->fpdu_part_rcvd += bytes;
1016 		if (srx->fpdu_part_rcvd < MIN_DDP_HDR)
1017 			return -EAGAIN;
1018 
1019 		if (unlikely(__ddp_get_version(c_hdr) != DDP_VERSION)) {
1020 			enum ddp_etype etype;
1021 			enum ddp_ecode ecode;
1022 
1023 			pr_warn("siw: received ddp version unsupported %d\n",
1024 				__ddp_get_version(c_hdr));
1025 
1026 			if (c_hdr->ddp_rdmap_ctrl & DDP_FLAG_TAGGED) {
1027 				etype = DDP_ETYPE_TAGGED_BUF;
1028 				ecode = DDP_ECODE_T_VERSION;
1029 			} else {
1030 				etype = DDP_ETYPE_UNTAGGED_BUF;
1031 				ecode = DDP_ECODE_UT_VERSION;
1032 			}
1033 			siw_init_terminate(rx_qp(srx), TERM_ERROR_LAYER_DDP,
1034 					   etype, ecode, 0);
1035 			return -EINVAL;
1036 		}
1037 		if (unlikely(__rdmap_get_version(c_hdr) != RDMAP_VERSION)) {
1038 			pr_warn("siw: received rdmap version unsupported %d\n",
1039 				__rdmap_get_version(c_hdr));
1040 
1041 			siw_init_terminate(rx_qp(srx), TERM_ERROR_LAYER_RDMAP,
1042 					   RDMAP_ETYPE_REMOTE_OPERATION,
1043 					   RDMAP_ECODE_VERSION, 0);
1044 			return -EINVAL;
1045 		}
1046 		opcode = __rdmap_get_opcode(c_hdr);
1047 
1048 		if (opcode > RDMAP_TERMINATE) {
1049 			pr_warn("siw: received unknown packet type %u\n",
1050 				opcode);
1051 
1052 			siw_init_terminate(rx_qp(srx), TERM_ERROR_LAYER_RDMAP,
1053 					   RDMAP_ETYPE_REMOTE_OPERATION,
1054 					   RDMAP_ECODE_OPCODE, 0);
1055 			return -EINVAL;
1056 		}
1057 		siw_dbg_qp(rx_qp(srx), "new header, opcode %u\n", opcode);
1058 	} else {
1059 		opcode = __rdmap_get_opcode(c_hdr);
1060 	}
1061 	set_rx_fpdu_context(qp, opcode);
1062 	frx = qp->rx_fpdu;
1063 
1064 	/*
1065 	 * Figure out len of current hdr: variable length of
1066 	 * iwarp hdr may force us to copy hdr information in
1067 	 * two steps. Only tagged DDP messages are already
1068 	 * completely received.
1069 	 */
1070 	if (iwarp_pktinfo[opcode].hdr_len > sizeof(struct iwarp_ctrl_tagged)) {
1071 		int hdrlen = iwarp_pktinfo[opcode].hdr_len;
1072 
1073 		bytes = min_t(int, hdrlen - MIN_DDP_HDR, srx->skb_new);
1074 
1075 		skb_copy_bits(skb, srx->skb_offset,
1076 			      (char *)c_hdr + srx->fpdu_part_rcvd, bytes);
1077 
1078 		siw_update_skb_rcvd(srx, bytes);
1079 		srx->fpdu_part_rcvd += bytes;
1080 		if (srx->fpdu_part_rcvd < hdrlen)
1081 			return -EAGAIN;
1082 	}
1083 
1084 	/*
1085 	 * DDP/RDMAP header receive completed. Check if the current
1086 	 * DDP segment starts a new RDMAP message or continues a previously
1087 	 * started RDMAP message.
1088 	 *
1089 	 * Alternating reception of DDP segments (or FPDUs) from incomplete
1090 	 * tagged and untagged RDMAP messages is supported, as long as
1091 	 * the current tagged or untagged message gets eventually completed
1092 	 * w/o intersection from another message of the same type
1093 	 * (tagged/untagged). E.g., a WRITE can get intersected by a SEND,
1094 	 * but not by a READ RESPONSE etc.
1095 	 */
1096 	if (srx->mpa_crc_enabled) {
1097 		/*
1098 		 * Restart CRC computation
1099 		 */
1100 		siw_crc_init(&srx->mpa_crc);
1101 		siw_crc_update(&srx->mpa_crc, c_hdr, srx->fpdu_part_rcvd);
1102 	}
1103 	if (frx->more_ddp_segs) {
1104 		frx->first_ddp_seg = 0;
1105 		if (frx->prev_rdmap_op != opcode) {
1106 			pr_warn("siw: packet intersection: %u : %u\n",
1107 				frx->prev_rdmap_op, opcode);
1108 			/*
1109 			 * The last inbound RDMA operation of same type
1110 			 * (tagged or untagged) is left unfinished.
1111 			 * To complete it in error, make it the current
1112 			 * operation again, even with the header already
1113 			 * overwritten. For error handling, only the opcode
1114 			 * and current rx context are relevant.
1115 			 */
1116 			set_rx_fpdu_context(qp, frx->prev_rdmap_op);
1117 			__rdmap_set_opcode(c_hdr, frx->prev_rdmap_op);
1118 			return -EPROTO;
1119 		}
1120 	} else {
1121 		frx->prev_rdmap_op = opcode;
1122 		frx->first_ddp_seg = 1;
1123 	}
1124 	frx->more_ddp_segs = c_hdr->ddp_rdmap_ctrl & DDP_FLAG_LAST ? 0 : 1;
1125 
1126 	return 0;
1127 }
1128 
siw_check_tx_fence(struct siw_qp * qp)1129 static int siw_check_tx_fence(struct siw_qp *qp)
1130 {
1131 	struct siw_wqe *tx_waiting = tx_wqe(qp);
1132 	struct siw_sqe *rreq;
1133 	int resume_tx = 0, rv = 0;
1134 	unsigned long flags;
1135 
1136 	spin_lock_irqsave(&qp->orq_lock, flags);
1137 
1138 	/* free current orq entry */
1139 	rreq = orq_get_current(qp);
1140 	WRITE_ONCE(rreq->flags, 0);
1141 
1142 	qp->orq_get++;
1143 
1144 	if (qp->tx_ctx.orq_fence) {
1145 		if (unlikely(tx_waiting->wr_status != SIW_WR_QUEUED)) {
1146 			pr_warn("siw: [QP %u]: fence resume: bad status %d\n",
1147 				qp_id(qp), tx_waiting->wr_status);
1148 			rv = -EPROTO;
1149 			goto out;
1150 		}
1151 		/* resume SQ processing, if possible */
1152 		if (tx_waiting->sqe.opcode == SIW_OP_READ ||
1153 		    tx_waiting->sqe.opcode == SIW_OP_READ_LOCAL_INV) {
1154 
1155 			/* SQ processing was stopped because of a full ORQ */
1156 			rreq = orq_get_free(qp);
1157 			if (unlikely(!rreq)) {
1158 				pr_warn("siw: [QP %u]: no ORQE\n", qp_id(qp));
1159 				rv = -EPROTO;
1160 				goto out;
1161 			}
1162 			siw_read_to_orq(rreq, &tx_waiting->sqe);
1163 
1164 			qp->orq_put++;
1165 			qp->tx_ctx.orq_fence = 0;
1166 			resume_tx = 1;
1167 
1168 		} else if (siw_orq_empty(qp)) {
1169 			/*
1170 			 * SQ processing was stopped by fenced work request.
1171 			 * Resume since all previous Read's are now completed.
1172 			 */
1173 			qp->tx_ctx.orq_fence = 0;
1174 			resume_tx = 1;
1175 		}
1176 	}
1177 out:
1178 	spin_unlock_irqrestore(&qp->orq_lock, flags);
1179 
1180 	if (resume_tx)
1181 		rv = siw_sq_start(qp);
1182 
1183 	return rv;
1184 }
1185 
1186 /*
1187  * siw_rdmap_complete()
1188  *
1189  * Complete processing of an RDMA message after receiving all
1190  * DDP segmens or ABort processing after encountering error case.
1191  *
1192  *   o SENDs + RRESPs will need for completion,
1193  *   o RREQs need for  READ RESPONSE initialization
1194  *   o WRITEs need memory dereferencing
1195  *
1196  * TODO: Failed WRITEs need local error to be surfaced.
1197  */
siw_rdmap_complete(struct siw_qp * qp,int error)1198 static int siw_rdmap_complete(struct siw_qp *qp, int error)
1199 {
1200 	struct siw_rx_stream *srx = &qp->rx_stream;
1201 	struct siw_wqe *wqe = rx_wqe(qp->rx_fpdu);
1202 	enum siw_wc_status wc_status = wqe->wc_status;
1203 	u8 opcode = __rdmap_get_opcode(&srx->hdr.ctrl);
1204 	int rv = 0;
1205 
1206 	switch (opcode) {
1207 	case RDMAP_SEND_SE:
1208 	case RDMAP_SEND_SE_INVAL:
1209 		wqe->rqe.flags |= SIW_WQE_SOLICITED;
1210 		fallthrough;
1211 
1212 	case RDMAP_SEND:
1213 	case RDMAP_SEND_INVAL:
1214 		if (wqe->wr_status == SIW_WR_IDLE)
1215 			break;
1216 
1217 		srx->ddp_msn[RDMAP_UNTAGGED_QN_SEND]++;
1218 
1219 		if (error != 0 && wc_status == SIW_WC_SUCCESS)
1220 			wc_status = SIW_WC_GENERAL_ERR;
1221 		/*
1222 		 * Handle STag invalidation request
1223 		 */
1224 		if (wc_status == SIW_WC_SUCCESS &&
1225 		    (opcode == RDMAP_SEND_INVAL ||
1226 		     opcode == RDMAP_SEND_SE_INVAL)) {
1227 			rv = siw_invalidate_stag(qp->pd, srx->inval_stag);
1228 			if (rv) {
1229 				siw_init_terminate(
1230 					qp, TERM_ERROR_LAYER_RDMAP,
1231 					rv == -EACCES ?
1232 						RDMAP_ETYPE_REMOTE_PROTECTION :
1233 						RDMAP_ETYPE_REMOTE_OPERATION,
1234 					RDMAP_ECODE_CANNOT_INVALIDATE, 0);
1235 
1236 				wc_status = SIW_WC_REM_INV_REQ_ERR;
1237 			}
1238 			rv = siw_rqe_complete(qp, &wqe->rqe, wqe->processed,
1239 					      rv ? 0 : srx->inval_stag,
1240 					      wc_status);
1241 		} else {
1242 			rv = siw_rqe_complete(qp, &wqe->rqe, wqe->processed,
1243 					      0, wc_status);
1244 		}
1245 		siw_wqe_put_mem(wqe, SIW_OP_RECEIVE);
1246 		break;
1247 
1248 	case RDMAP_RDMA_READ_RESP:
1249 		if (wqe->wr_status == SIW_WR_IDLE)
1250 			break;
1251 
1252 		if (error != 0) {
1253 			if ((srx->state == SIW_GET_HDR &&
1254 			     qp->rx_fpdu->first_ddp_seg) || error == -ENODATA)
1255 				/* possible RREQ in ORQ left untouched */
1256 				break;
1257 
1258 			if (wc_status == SIW_WC_SUCCESS)
1259 				wc_status = SIW_WC_GENERAL_ERR;
1260 		} else if (rdma_is_kernel_res(&qp->base_qp.res) &&
1261 			   rx_type(wqe) == SIW_OP_READ_LOCAL_INV) {
1262 			/*
1263 			 * Handle any STag invalidation request
1264 			 */
1265 			rv = siw_invalidate_stag(qp->pd, wqe->sqe.sge[0].lkey);
1266 			if (rv) {
1267 				siw_init_terminate(qp, TERM_ERROR_LAYER_RDMAP,
1268 						   RDMAP_ETYPE_CATASTROPHIC,
1269 						   RDMAP_ECODE_UNSPECIFIED, 0);
1270 
1271 				if (wc_status == SIW_WC_SUCCESS) {
1272 					wc_status = SIW_WC_GENERAL_ERR;
1273 					error = rv;
1274 				}
1275 			}
1276 		}
1277 		/*
1278 		 * All errors turn the wqe into signalled.
1279 		 */
1280 		if ((wqe->sqe.flags & SIW_WQE_SIGNALLED) || error != 0)
1281 			rv = siw_sqe_complete(qp, &wqe->sqe, wqe->processed,
1282 					      wc_status);
1283 		siw_wqe_put_mem(wqe, SIW_OP_READ);
1284 
1285 		if (!error) {
1286 			rv = siw_check_tx_fence(qp);
1287 		} else {
1288 			/* Disable current ORQ element */
1289 			if (qp->attrs.orq_size)
1290 				WRITE_ONCE(orq_get_current(qp)->flags, 0);
1291 		}
1292 		break;
1293 
1294 	case RDMAP_RDMA_READ_REQ:
1295 		if (!error) {
1296 			rv = siw_init_rresp(qp, srx);
1297 			srx->ddp_msn[RDMAP_UNTAGGED_QN_RDMA_READ]++;
1298 		}
1299 		break;
1300 
1301 	case RDMAP_RDMA_WRITE:
1302 		if (wqe->wr_status == SIW_WR_IDLE)
1303 			break;
1304 
1305 		/*
1306 		 * Free References from memory object if
1307 		 * attached to receive context (inbound WRITE).
1308 		 * While a zero-length WRITE is allowed,
1309 		 * no memory reference got created.
1310 		 */
1311 		if (rx_mem(&qp->rx_tagged)) {
1312 			siw_mem_put(rx_mem(&qp->rx_tagged));
1313 			rx_mem(&qp->rx_tagged) = NULL;
1314 		}
1315 		break;
1316 
1317 	default:
1318 		break;
1319 	}
1320 	wqe->wr_status = SIW_WR_IDLE;
1321 
1322 	return rv;
1323 }
1324 
1325 /*
1326  * siw_tcp_rx_data()
1327  *
1328  * Main routine to consume inbound TCP payload
1329  *
1330  * @rd_desc:	read descriptor
1331  * @skb:	socket buffer
1332  * @off:	offset in skb
1333  * @len:	skb->len - offset : payload in skb
1334  */
siw_tcp_rx_data(read_descriptor_t * rd_desc,struct sk_buff * skb,unsigned int off,size_t len)1335 int siw_tcp_rx_data(read_descriptor_t *rd_desc, struct sk_buff *skb,
1336 		    unsigned int off, size_t len)
1337 {
1338 	struct siw_qp *qp = rd_desc->arg.data;
1339 	struct siw_rx_stream *srx = &qp->rx_stream;
1340 	int rv;
1341 
1342 	srx->skb = skb;
1343 	srx->skb_new = skb->len - off;
1344 	srx->skb_offset = off;
1345 	srx->skb_copied = 0;
1346 
1347 	siw_dbg_qp(qp, "new data, len %d\n", srx->skb_new);
1348 
1349 	while (srx->skb_new) {
1350 		int run_completion = 1;
1351 
1352 		if (unlikely(srx->rx_suspend)) {
1353 			/* Do not process any more data */
1354 			srx->skb_copied += srx->skb_new;
1355 			break;
1356 		}
1357 		switch (srx->state) {
1358 		case SIW_GET_HDR:
1359 			rv = siw_get_hdr(srx);
1360 			if (!rv) {
1361 				srx->fpdu_part_rem =
1362 					be16_to_cpu(srx->hdr.ctrl.mpa_len) -
1363 					srx->fpdu_part_rcvd + MPA_HDR_SIZE;
1364 
1365 				if (srx->fpdu_part_rem)
1366 					srx->pad = -srx->fpdu_part_rem & 0x3;
1367 				else
1368 					srx->pad = 0;
1369 
1370 				srx->state = SIW_GET_DATA_START;
1371 				srx->fpdu_part_rcvd = 0;
1372 			}
1373 			break;
1374 
1375 		case SIW_GET_DATA_MORE:
1376 			/*
1377 			 * Another data fragment of the same DDP segment.
1378 			 * Setting first_ddp_seg = 0 avoids repeating
1379 			 * initializations that shall occur only once per
1380 			 * DDP segment.
1381 			 */
1382 			qp->rx_fpdu->first_ddp_seg = 0;
1383 			fallthrough;
1384 
1385 		case SIW_GET_DATA_START:
1386 			/*
1387 			 * Headers will be checked by the opcode-specific
1388 			 * data receive function below.
1389 			 */
1390 			rv = iwarp_pktinfo[qp->rx_stream.rdmap_op].rx_data(qp);
1391 			if (!rv) {
1392 				int mpa_len =
1393 					be16_to_cpu(srx->hdr.ctrl.mpa_len)
1394 					+ MPA_HDR_SIZE;
1395 
1396 				srx->fpdu_part_rem = (-mpa_len & 0x3)
1397 						      + MPA_CRC_SIZE;
1398 				srx->fpdu_part_rcvd = 0;
1399 				srx->state = SIW_GET_TRAILER;
1400 			} else {
1401 				if (unlikely(rv == -ECONNRESET))
1402 					run_completion = 0;
1403 				else
1404 					srx->state = SIW_GET_DATA_MORE;
1405 			}
1406 			break;
1407 
1408 		case SIW_GET_TRAILER:
1409 			/*
1410 			 * read CRC + any padding
1411 			 */
1412 			rv = siw_get_trailer(qp, srx);
1413 			if (likely(!rv)) {
1414 				/*
1415 				 * FPDU completed.
1416 				 * complete RDMAP message if last fragment
1417 				 */
1418 				srx->state = SIW_GET_HDR;
1419 				srx->fpdu_part_rcvd = 0;
1420 
1421 				if (!(srx->hdr.ctrl.ddp_rdmap_ctrl &
1422 				      DDP_FLAG_LAST))
1423 					/* more frags */
1424 					break;
1425 
1426 				rv = siw_rdmap_complete(qp, 0);
1427 				run_completion = 0;
1428 			}
1429 			break;
1430 
1431 		default:
1432 			pr_warn("QP[%u]: RX out of state\n", qp_id(qp));
1433 			rv = -EPROTO;
1434 			run_completion = 0;
1435 		}
1436 		if (unlikely(rv != 0 && rv != -EAGAIN)) {
1437 			if ((srx->state > SIW_GET_HDR ||
1438 			     qp->rx_fpdu->more_ddp_segs) && run_completion)
1439 				siw_rdmap_complete(qp, rv);
1440 
1441 			siw_dbg_qp(qp, "rx error %d, rx state %d\n", rv,
1442 				   srx->state);
1443 
1444 			siw_qp_cm_drop(qp, 1);
1445 
1446 			break;
1447 		}
1448 		if (rv) {
1449 			siw_dbg_qp(qp, "fpdu fragment, state %d, missing %d\n",
1450 				   srx->state, srx->fpdu_part_rem);
1451 			break;
1452 		}
1453 	}
1454 	return srx->skb_copied;
1455 }
1456