1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (c) 2016 Chelsio Communications, Inc.
4 */
5
6#include <linux/workqueue.h>
7#include <linux/kthread.h>
8#include <linux/sched/signal.h>
9
10#include <asm/unaligned.h>
11#include <net/tcp.h>
12#include <target/target_core_base.h>
13#include <target/target_core_fabric.h>
14#include "cxgbit.h"
15
16struct sge_opaque_hdr {
17	void *dev;
18	dma_addr_t addr[MAX_SKB_FRAGS + 1];
19};
20
21static const u8 cxgbit_digest_len[] = {0, 4, 4, 8};
22
23#define TX_HDR_LEN (sizeof(struct sge_opaque_hdr) + \
24		    sizeof(struct fw_ofld_tx_data_wr))
25
26static struct sk_buff *
27__cxgbit_alloc_skb(struct cxgbit_sock *csk, u32 len, bool iso)
28{
29	struct sk_buff *skb = NULL;
30	u8 submode = 0;
31	int errcode;
32	static const u32 hdr_len = TX_HDR_LEN + ISCSI_HDR_LEN;
33
34	if (len) {
35		skb = alloc_skb_with_frags(hdr_len, len,
36					   0, &errcode,
37					   GFP_KERNEL);
38		if (!skb)
39			return NULL;
40
41		skb_reserve(skb, TX_HDR_LEN);
42		skb_reset_transport_header(skb);
43		__skb_put(skb, ISCSI_HDR_LEN);
44		skb->data_len = len;
45		skb->len += len;
46		submode |= (csk->submode & CXGBIT_SUBMODE_DCRC);
47
48	} else {
49		u32 iso_len = iso ? sizeof(struct cpl_tx_data_iso) : 0;
50
51		skb = alloc_skb(hdr_len + iso_len, GFP_KERNEL);
52		if (!skb)
53			return NULL;
54
55		skb_reserve(skb, TX_HDR_LEN + iso_len);
56		skb_reset_transport_header(skb);
57		__skb_put(skb, ISCSI_HDR_LEN);
58	}
59
60	submode |= (csk->submode & CXGBIT_SUBMODE_HCRC);
61	cxgbit_skcb_submode(skb) = submode;
62	cxgbit_skcb_tx_extralen(skb) = cxgbit_digest_len[submode];
63	cxgbit_skcb_flags(skb) |= SKCBF_TX_NEED_HDR;
64	return skb;
65}
66
67static struct sk_buff *cxgbit_alloc_skb(struct cxgbit_sock *csk, u32 len)
68{
69	return __cxgbit_alloc_skb(csk, len, false);
70}
71
72/*
73 * cxgbit_is_ofld_imm - check whether a packet can be sent as immediate data
74 * @skb: the packet
75 *
76 * Returns true if a packet can be sent as an offload WR with immediate
77 * data.  We currently use the same limit as for Ethernet packets.
78 */
79static int cxgbit_is_ofld_imm(const struct sk_buff *skb)
80{
81	int length = skb->len;
82
83	if (likely(cxgbit_skcb_flags(skb) & SKCBF_TX_NEED_HDR))
84		length += sizeof(struct fw_ofld_tx_data_wr);
85
86	if (likely(cxgbit_skcb_flags(skb) & SKCBF_TX_ISO))
87		length += sizeof(struct cpl_tx_data_iso);
88
89	return length <= MAX_IMM_OFLD_TX_DATA_WR_LEN;
90}
91
92/*
93 * cxgbit_sgl_len - calculates the size of an SGL of the given capacity
94 * @n: the number of SGL entries
95 * Calculates the number of flits needed for a scatter/gather list that
96 * can hold the given number of entries.
97 */
98static inline unsigned int cxgbit_sgl_len(unsigned int n)
99{
100	n--;
101	return (3 * n) / 2 + (n & 1) + 2;
102}
103
104/*
105 * cxgbit_calc_tx_flits_ofld - calculate # of flits for an offload packet
106 * @skb: the packet
107 *
108 * Returns the number of flits needed for the given offload packet.
109 * These packets are already fully constructed and no additional headers
110 * will be added.
111 */
112static unsigned int cxgbit_calc_tx_flits_ofld(const struct sk_buff *skb)
113{
114	unsigned int flits, cnt;
115
116	if (cxgbit_is_ofld_imm(skb))
117		return DIV_ROUND_UP(skb->len, 8);
118	flits = skb_transport_offset(skb) / 8;
119	cnt = skb_shinfo(skb)->nr_frags;
120	if (skb_tail_pointer(skb) != skb_transport_header(skb))
121		cnt++;
122	return flits + cxgbit_sgl_len(cnt);
123}
124
125#define CXGBIT_ISO_FSLICE 0x1
126#define CXGBIT_ISO_LSLICE 0x2
127static void
128cxgbit_cpl_tx_data_iso(struct sk_buff *skb, struct cxgbit_iso_info *iso_info)
129{
130	struct cpl_tx_data_iso *cpl;
131	unsigned int submode = cxgbit_skcb_submode(skb);
132	unsigned int fslice = !!(iso_info->flags & CXGBIT_ISO_FSLICE);
133	unsigned int lslice = !!(iso_info->flags & CXGBIT_ISO_LSLICE);
134
135	cpl = __skb_push(skb, sizeof(*cpl));
136
137	cpl->op_to_scsi = htonl(CPL_TX_DATA_ISO_OP_V(CPL_TX_DATA_ISO) |
138			CPL_TX_DATA_ISO_FIRST_V(fslice) |
139			CPL_TX_DATA_ISO_LAST_V(lslice) |
140			CPL_TX_DATA_ISO_CPLHDRLEN_V(0) |
141			CPL_TX_DATA_ISO_HDRCRC_V(submode & 1) |
142			CPL_TX_DATA_ISO_PLDCRC_V(((submode >> 1) & 1)) |
143			CPL_TX_DATA_ISO_IMMEDIATE_V(0) |
144			CPL_TX_DATA_ISO_SCSI_V(2));
145
146	cpl->ahs_len = 0;
147	cpl->mpdu = htons(DIV_ROUND_UP(iso_info->mpdu, 4));
148	cpl->burst_size = htonl(DIV_ROUND_UP(iso_info->burst_len, 4));
149	cpl->len = htonl(iso_info->len);
150	cpl->reserved2_seglen_offset = htonl(0);
151	cpl->datasn_offset = htonl(0);
152	cpl->buffer_offset = htonl(0);
153	cpl->reserved3 = 0;
154
155	__skb_pull(skb, sizeof(*cpl));
156}
157
158static void
159cxgbit_tx_data_wr(struct cxgbit_sock *csk, struct sk_buff *skb, u32 dlen,
160		  u32 len, u32 credits, u32 compl)
161{
162	struct fw_ofld_tx_data_wr *req;
163	const struct cxgb4_lld_info *lldi = &csk->com.cdev->lldi;
164	u32 submode = cxgbit_skcb_submode(skb);
165	u32 wr_ulp_mode = 0;
166	u32 hdr_size = sizeof(*req);
167	u32 opcode = FW_OFLD_TX_DATA_WR;
168	u32 immlen = 0;
169	u32 force = is_t5(lldi->adapter_type) ? TX_FORCE_V(!submode) :
170		    T6_TX_FORCE_F;
171
172	if (cxgbit_skcb_flags(skb) & SKCBF_TX_ISO) {
173		opcode = FW_ISCSI_TX_DATA_WR;
174		immlen += sizeof(struct cpl_tx_data_iso);
175		hdr_size += sizeof(struct cpl_tx_data_iso);
176		submode |= 8;
177	}
178
179	if (cxgbit_is_ofld_imm(skb))
180		immlen += dlen;
181
182	req = __skb_push(skb, hdr_size);
183	req->op_to_immdlen = cpu_to_be32(FW_WR_OP_V(opcode) |
184					FW_WR_COMPL_V(compl) |
185					FW_WR_IMMDLEN_V(immlen));
186	req->flowid_len16 = cpu_to_be32(FW_WR_FLOWID_V(csk->tid) |
187					FW_WR_LEN16_V(credits));
188	req->plen = htonl(len);
189	wr_ulp_mode = FW_OFLD_TX_DATA_WR_ULPMODE_V(ULP_MODE_ISCSI) |
190				FW_OFLD_TX_DATA_WR_ULPSUBMODE_V(submode);
191
192	req->tunnel_to_proxy = htonl(wr_ulp_mode | force |
193				     FW_OFLD_TX_DATA_WR_SHOVE_F);
194}
195
196static void cxgbit_arp_failure_skb_discard(void *handle, struct sk_buff *skb)
197{
198	kfree_skb(skb);
199}
200
201void cxgbit_push_tx_frames(struct cxgbit_sock *csk)
202{
203	struct sk_buff *skb;
204
205	while (csk->wr_cred && ((skb = skb_peek(&csk->txq)) != NULL)) {
206		u32 dlen = skb->len;
207		u32 len = skb->len;
208		u32 credits_needed;
209		u32 compl = 0;
210		u32 flowclen16 = 0;
211		u32 iso_cpl_len = 0;
212
213		if (cxgbit_skcb_flags(skb) & SKCBF_TX_ISO)
214			iso_cpl_len = sizeof(struct cpl_tx_data_iso);
215
216		if (cxgbit_is_ofld_imm(skb))
217			credits_needed = DIV_ROUND_UP(dlen + iso_cpl_len, 16);
218		else
219			credits_needed = DIV_ROUND_UP((8 *
220					cxgbit_calc_tx_flits_ofld(skb)) +
221					iso_cpl_len, 16);
222
223		if (likely(cxgbit_skcb_flags(skb) & SKCBF_TX_NEED_HDR))
224			credits_needed += DIV_ROUND_UP(
225				sizeof(struct fw_ofld_tx_data_wr), 16);
226		/*
227		 * Assumes the initial credits is large enough to support
228		 * fw_flowc_wr plus largest possible first payload
229		 */
230
231		if (!test_and_set_bit(CSK_TX_DATA_SENT, &csk->com.flags)) {
232			flowclen16 = cxgbit_send_tx_flowc_wr(csk);
233			csk->wr_cred -= flowclen16;
234			csk->wr_una_cred += flowclen16;
235		}
236
237		if (csk->wr_cred < credits_needed) {
238			pr_debug("csk 0x%p, skb %u/%u, wr %d < %u.\n",
239				 csk, skb->len, skb->data_len,
240				 credits_needed, csk->wr_cred);
241			break;
242		}
243		__skb_unlink(skb, &csk->txq);
244		set_wr_txq(skb, CPL_PRIORITY_DATA, csk->txq_idx);
245		skb->csum = (__force __wsum)(credits_needed + flowclen16);
246		csk->wr_cred -= credits_needed;
247		csk->wr_una_cred += credits_needed;
248
249		pr_debug("csk 0x%p, skb %u/%u, wr %d, left %u, unack %u.\n",
250			 csk, skb->len, skb->data_len, credits_needed,
251			 csk->wr_cred, csk->wr_una_cred);
252
253		if (likely(cxgbit_skcb_flags(skb) & SKCBF_TX_NEED_HDR)) {
254			len += cxgbit_skcb_tx_extralen(skb);
255
256			if ((csk->wr_una_cred >= (csk->wr_max_cred / 2)) ||
257			    (!before(csk->write_seq,
258				     csk->snd_una + csk->snd_win))) {
259				compl = 1;
260				csk->wr_una_cred = 0;
261			}
262
263			cxgbit_tx_data_wr(csk, skb, dlen, len, credits_needed,
264					  compl);
265			csk->snd_nxt += len;
266
267		} else if ((cxgbit_skcb_flags(skb) & SKCBF_TX_FLAG_COMPL) ||
268			   (csk->wr_una_cred >= (csk->wr_max_cred / 2))) {
269			struct cpl_close_con_req *req =
270				(struct cpl_close_con_req *)skb->data;
271			req->wr.wr_hi |= htonl(FW_WR_COMPL_F);
272			csk->wr_una_cred = 0;
273		}
274
275		cxgbit_sock_enqueue_wr(csk, skb);
276		t4_set_arp_err_handler(skb, csk,
277				       cxgbit_arp_failure_skb_discard);
278
279		pr_debug("csk 0x%p,%u, skb 0x%p, %u.\n",
280			 csk, csk->tid, skb, len);
281
282		cxgbit_l2t_send(csk->com.cdev, skb, csk->l2t);
283	}
284}
285
286static void cxgbit_unlock_sock(struct cxgbit_sock *csk)
287{
288	struct sk_buff_head backlogq;
289	struct sk_buff *skb;
290	void (*fn)(struct cxgbit_sock *, struct sk_buff *);
291
292	skb_queue_head_init(&backlogq);
293
294	spin_lock_bh(&csk->lock);
295	while (skb_queue_len(&csk->backlogq)) {
296		skb_queue_splice_init(&csk->backlogq, &backlogq);
297		spin_unlock_bh(&csk->lock);
298
299		while ((skb = __skb_dequeue(&backlogq))) {
300			fn = cxgbit_skcb_rx_backlog_fn(skb);
301			fn(csk, skb);
302		}
303
304		spin_lock_bh(&csk->lock);
305	}
306
307	csk->lock_owner = false;
308	spin_unlock_bh(&csk->lock);
309}
310
311static int cxgbit_queue_skb(struct cxgbit_sock *csk, struct sk_buff *skb)
312{
313	int ret = 0;
314
315	spin_lock_bh(&csk->lock);
316	csk->lock_owner = true;
317	spin_unlock_bh(&csk->lock);
318
319	if (unlikely((csk->com.state != CSK_STATE_ESTABLISHED) ||
320		     signal_pending(current))) {
321		__kfree_skb(skb);
322		__skb_queue_purge(&csk->ppodq);
323		ret = -1;
324		goto unlock;
325	}
326
327	csk->write_seq += skb->len +
328			  cxgbit_skcb_tx_extralen(skb);
329
330	skb_queue_splice_tail_init(&csk->ppodq, &csk->txq);
331	__skb_queue_tail(&csk->txq, skb);
332	cxgbit_push_tx_frames(csk);
333
334unlock:
335	cxgbit_unlock_sock(csk);
336	return ret;
337}
338
339static int
340cxgbit_map_skb(struct iscsit_cmd *cmd, struct sk_buff *skb, u32 data_offset,
341	       u32 data_length)
342{
343	u32 i = 0, nr_frags = MAX_SKB_FRAGS;
344	u32 padding = ((-data_length) & 3);
345	struct scatterlist *sg;
346	struct page *page;
347	unsigned int page_off;
348
349	if (padding)
350		nr_frags--;
351
352	/*
353	 * We know each entry in t_data_sg contains a page.
354	 */
355	sg = &cmd->se_cmd.t_data_sg[data_offset / PAGE_SIZE];
356	page_off = (data_offset % PAGE_SIZE);
357
358	while (data_length && (i < nr_frags)) {
359		u32 cur_len = min_t(u32, data_length, sg->length - page_off);
360
361		page = sg_page(sg);
362
363		get_page(page);
364		skb_fill_page_desc(skb, i, page, sg->offset + page_off,
365				   cur_len);
366		skb->data_len += cur_len;
367		skb->len += cur_len;
368		skb->truesize += cur_len;
369
370		data_length -= cur_len;
371		page_off = 0;
372		sg = sg_next(sg);
373		i++;
374	}
375
376	if (data_length)
377		return -1;
378
379	if (padding) {
380		page = alloc_page(GFP_KERNEL | __GFP_ZERO);
381		if (!page)
382			return -1;
383		skb_fill_page_desc(skb, i, page, 0, padding);
384		skb->data_len += padding;
385		skb->len += padding;
386		skb->truesize += padding;
387	}
388
389	return 0;
390}
391
392static int
393cxgbit_tx_datain_iso(struct cxgbit_sock *csk, struct iscsit_cmd *cmd,
394		     struct iscsi_datain_req *dr)
395{
396	struct iscsit_conn *conn = csk->conn;
397	struct sk_buff *skb;
398	struct iscsi_datain datain;
399	struct cxgbit_iso_info iso_info;
400	u32 data_length = cmd->se_cmd.data_length;
401	u32 mrdsl = conn->conn_ops->MaxRecvDataSegmentLength;
402	u32 num_pdu, plen, tx_data = 0;
403	bool task_sense = !!(cmd->se_cmd.se_cmd_flags &
404		SCF_TRANSPORT_TASK_SENSE);
405	bool set_statsn = false;
406	int ret = -1;
407
408	while (data_length) {
409		num_pdu = (data_length + mrdsl - 1) / mrdsl;
410		if (num_pdu > csk->max_iso_npdu)
411			num_pdu = csk->max_iso_npdu;
412
413		plen = num_pdu * mrdsl;
414		if (plen > data_length)
415			plen = data_length;
416
417		skb = __cxgbit_alloc_skb(csk, 0, true);
418		if (unlikely(!skb))
419			return -ENOMEM;
420
421		memset(skb->data, 0, ISCSI_HDR_LEN);
422		cxgbit_skcb_flags(skb) |= SKCBF_TX_ISO;
423		cxgbit_skcb_submode(skb) |= (csk->submode &
424				CXGBIT_SUBMODE_DCRC);
425		cxgbit_skcb_tx_extralen(skb) = (num_pdu *
426				cxgbit_digest_len[cxgbit_skcb_submode(skb)]) +
427						((num_pdu - 1) * ISCSI_HDR_LEN);
428
429		memset(&datain, 0, sizeof(struct iscsi_datain));
430		memset(&iso_info, 0, sizeof(iso_info));
431
432		if (!tx_data)
433			iso_info.flags |= CXGBIT_ISO_FSLICE;
434
435		if (!(data_length - plen)) {
436			iso_info.flags |= CXGBIT_ISO_LSLICE;
437			if (!task_sense) {
438				datain.flags = ISCSI_FLAG_DATA_STATUS;
439				iscsit_increment_maxcmdsn(cmd, conn->sess);
440				cmd->stat_sn = conn->stat_sn++;
441				set_statsn = true;
442			}
443		}
444
445		iso_info.burst_len = num_pdu * mrdsl;
446		iso_info.mpdu = mrdsl;
447		iso_info.len = ISCSI_HDR_LEN + plen;
448
449		cxgbit_cpl_tx_data_iso(skb, &iso_info);
450
451		datain.offset = tx_data;
452		datain.data_sn = cmd->data_sn - 1;
453
454		iscsit_build_datain_pdu(cmd, conn, &datain,
455					(struct iscsi_data_rsp *)skb->data,
456					set_statsn);
457
458		ret = cxgbit_map_skb(cmd, skb, tx_data, plen);
459		if (unlikely(ret)) {
460			__kfree_skb(skb);
461			goto out;
462		}
463
464		ret = cxgbit_queue_skb(csk, skb);
465		if (unlikely(ret))
466			goto out;
467
468		tx_data += plen;
469		data_length -= plen;
470
471		cmd->read_data_done += plen;
472		cmd->data_sn += num_pdu;
473	}
474
475	dr->dr_complete = DATAIN_COMPLETE_NORMAL;
476
477	return 0;
478
479out:
480	return ret;
481}
482
483static int
484cxgbit_tx_datain(struct cxgbit_sock *csk, struct iscsit_cmd *cmd,
485		 const struct iscsi_datain *datain)
486{
487	struct sk_buff *skb;
488	int ret = 0;
489
490	skb = cxgbit_alloc_skb(csk, 0);
491	if (unlikely(!skb))
492		return -ENOMEM;
493
494	memcpy(skb->data, cmd->pdu, ISCSI_HDR_LEN);
495
496	if (datain->length) {
497		cxgbit_skcb_submode(skb) |= (csk->submode &
498				CXGBIT_SUBMODE_DCRC);
499		cxgbit_skcb_tx_extralen(skb) =
500				cxgbit_digest_len[cxgbit_skcb_submode(skb)];
501	}
502
503	ret = cxgbit_map_skb(cmd, skb, datain->offset, datain->length);
504	if (ret < 0) {
505		__kfree_skb(skb);
506		return ret;
507	}
508
509	return cxgbit_queue_skb(csk, skb);
510}
511
512static int
513cxgbit_xmit_datain_pdu(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
514		       struct iscsi_datain_req *dr,
515		       const struct iscsi_datain *datain)
516{
517	struct cxgbit_sock *csk = conn->context;
518	u32 data_length = cmd->se_cmd.data_length;
519	u32 padding = ((-data_length) & 3);
520	u32 mrdsl = conn->conn_ops->MaxRecvDataSegmentLength;
521
522	if ((data_length > mrdsl) && (!dr->recovery) &&
523	    (!padding) && (!datain->offset) && csk->max_iso_npdu) {
524		atomic_long_add(data_length - datain->length,
525				&conn->sess->tx_data_octets);
526		return cxgbit_tx_datain_iso(csk, cmd, dr);
527	}
528
529	return cxgbit_tx_datain(csk, cmd, datain);
530}
531
532static int
533cxgbit_xmit_nondatain_pdu(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
534			  const void *data_buf, u32 data_buf_len)
535{
536	struct cxgbit_sock *csk = conn->context;
537	struct sk_buff *skb;
538	u32 padding = ((-data_buf_len) & 3);
539
540	skb = cxgbit_alloc_skb(csk, data_buf_len + padding);
541	if (unlikely(!skb))
542		return -ENOMEM;
543
544	memcpy(skb->data, cmd->pdu, ISCSI_HDR_LEN);
545
546	if (data_buf_len) {
547		u32 pad_bytes = 0;
548
549		skb_store_bits(skb, ISCSI_HDR_LEN, data_buf, data_buf_len);
550
551		if (padding)
552			skb_store_bits(skb, ISCSI_HDR_LEN + data_buf_len,
553				       &pad_bytes, padding);
554	}
555
556	cxgbit_skcb_tx_extralen(skb) = cxgbit_digest_len[
557				       cxgbit_skcb_submode(skb)];
558
559	return cxgbit_queue_skb(csk, skb);
560}
561
562int
563cxgbit_xmit_pdu(struct iscsit_conn *conn, struct iscsit_cmd *cmd,
564		struct iscsi_datain_req *dr, const void *buf, u32 buf_len)
565{
566	if (dr)
567		return cxgbit_xmit_datain_pdu(conn, cmd, dr, buf);
568	else
569		return cxgbit_xmit_nondatain_pdu(conn, cmd, buf, buf_len);
570}
571
572int cxgbit_validate_params(struct iscsit_conn *conn)
573{
574	struct cxgbit_sock *csk = conn->context;
575	struct cxgbit_device *cdev = csk->com.cdev;
576	struct iscsi_param *param;
577	u32 max_xmitdsl;
578
579	param = iscsi_find_param_from_key(MAXXMITDATASEGMENTLENGTH,
580					  conn->param_list);
581	if (!param)
582		return -1;
583
584	if (kstrtou32(param->value, 0, &max_xmitdsl) < 0)
585		return -1;
586
587	if (max_xmitdsl > cdev->mdsl) {
588		if (iscsi_change_param_sprintf(
589			conn, "MaxXmitDataSegmentLength=%u", cdev->mdsl))
590			return -1;
591	}
592
593	return 0;
594}
595
596static int cxgbit_set_digest(struct cxgbit_sock *csk)
597{
598	struct iscsit_conn *conn = csk->conn;
599	struct iscsi_param *param;
600
601	param = iscsi_find_param_from_key(HEADERDIGEST, conn->param_list);
602	if (!param) {
603		pr_err("param not found key %s\n", HEADERDIGEST);
604		return -1;
605	}
606
607	if (!strcmp(param->value, CRC32C))
608		csk->submode |= CXGBIT_SUBMODE_HCRC;
609
610	param = iscsi_find_param_from_key(DATADIGEST, conn->param_list);
611	if (!param) {
612		csk->submode = 0;
613		pr_err("param not found key %s\n", DATADIGEST);
614		return -1;
615	}
616
617	if (!strcmp(param->value, CRC32C))
618		csk->submode |= CXGBIT_SUBMODE_DCRC;
619
620	if (cxgbit_setup_conn_digest(csk)) {
621		csk->submode = 0;
622		return -1;
623	}
624
625	return 0;
626}
627
628static int cxgbit_set_iso_npdu(struct cxgbit_sock *csk)
629{
630	struct iscsit_conn *conn = csk->conn;
631	struct iscsi_conn_ops *conn_ops = conn->conn_ops;
632	struct iscsi_param *param;
633	u32 mrdsl, mbl;
634	u32 max_npdu, max_iso_npdu;
635	u32 max_iso_payload;
636
637	if (conn->login->leading_connection) {
638		param = iscsi_find_param_from_key(MAXBURSTLENGTH,
639						  conn->param_list);
640		if (!param) {
641			pr_err("param not found key %s\n", MAXBURSTLENGTH);
642			return -1;
643		}
644
645		if (kstrtou32(param->value, 0, &mbl) < 0)
646			return -1;
647	} else {
648		mbl = conn->sess->sess_ops->MaxBurstLength;
649	}
650
651	mrdsl = conn_ops->MaxRecvDataSegmentLength;
652	max_npdu = mbl / mrdsl;
653
654	max_iso_payload = rounddown(CXGBIT_MAX_ISO_PAYLOAD, csk->emss);
655
656	max_iso_npdu = max_iso_payload /
657		       (ISCSI_HDR_LEN + mrdsl +
658			cxgbit_digest_len[csk->submode]);
659
660	csk->max_iso_npdu = min(max_npdu, max_iso_npdu);
661
662	if (csk->max_iso_npdu <= 1)
663		csk->max_iso_npdu = 0;
664
665	return 0;
666}
667
668/*
669 * cxgbit_seq_pdu_inorder()
670 * @csk: pointer to cxgbit socket structure
671 *
672 * This function checks whether data sequence and data
673 * pdu are in order.
674 *
675 * Return: returns -1 on error, 0 if data sequence and
676 * data pdu are in order, 1 if data sequence or data pdu
677 * is not in order.
678 */
679static int cxgbit_seq_pdu_inorder(struct cxgbit_sock *csk)
680{
681	struct iscsit_conn *conn = csk->conn;
682	struct iscsi_param *param;
683
684	if (conn->login->leading_connection) {
685		param = iscsi_find_param_from_key(DATASEQUENCEINORDER,
686						  conn->param_list);
687		if (!param) {
688			pr_err("param not found key %s\n", DATASEQUENCEINORDER);
689			return -1;
690		}
691
692		if (strcmp(param->value, YES))
693			return 1;
694
695		param = iscsi_find_param_from_key(DATAPDUINORDER,
696						  conn->param_list);
697		if (!param) {
698			pr_err("param not found key %s\n", DATAPDUINORDER);
699			return -1;
700		}
701
702		if (strcmp(param->value, YES))
703			return 1;
704
705	} else {
706		if (!conn->sess->sess_ops->DataSequenceInOrder)
707			return 1;
708		if (!conn->sess->sess_ops->DataPDUInOrder)
709			return 1;
710	}
711
712	return 0;
713}
714
715static int cxgbit_set_params(struct iscsit_conn *conn)
716{
717	struct cxgbit_sock *csk = conn->context;
718	struct cxgbit_device *cdev = csk->com.cdev;
719	struct cxgbi_ppm *ppm = *csk->com.cdev->lldi.iscsi_ppm;
720	struct iscsi_conn_ops *conn_ops = conn->conn_ops;
721	struct iscsi_param *param;
722	u8 erl;
723
724	if (conn_ops->MaxRecvDataSegmentLength > cdev->mdsl)
725		conn_ops->MaxRecvDataSegmentLength = cdev->mdsl;
726
727	if (cxgbit_set_digest(csk))
728		return -1;
729
730	if (conn->login->leading_connection) {
731		param = iscsi_find_param_from_key(ERRORRECOVERYLEVEL,
732						  conn->param_list);
733		if (!param) {
734			pr_err("param not found key %s\n", ERRORRECOVERYLEVEL);
735			return -1;
736		}
737		if (kstrtou8(param->value, 0, &erl) < 0)
738			return -1;
739	} else {
740		erl = conn->sess->sess_ops->ErrorRecoveryLevel;
741	}
742
743	if (!erl) {
744		int ret;
745
746		ret = cxgbit_seq_pdu_inorder(csk);
747		if (ret < 0) {
748			return -1;
749		} else if (ret > 0) {
750			if (is_t5(cdev->lldi.adapter_type))
751				goto enable_ddp;
752			else
753				return 0;
754		}
755
756		if (test_bit(CDEV_ISO_ENABLE, &cdev->flags)) {
757			if (cxgbit_set_iso_npdu(csk))
758				return -1;
759		}
760
761enable_ddp:
762		if (test_bit(CDEV_DDP_ENABLE, &cdev->flags)) {
763			if (cxgbit_setup_conn_pgidx(csk,
764						    ppm->tformat.pgsz_idx_dflt))
765				return -1;
766			set_bit(CSK_DDP_ENABLE, &csk->com.flags);
767		}
768	}
769
770	return 0;
771}
772
773int
774cxgbit_put_login_tx(struct iscsit_conn *conn, struct iscsi_login *login,
775		    u32 length)
776{
777	struct cxgbit_sock *csk = conn->context;
778	struct sk_buff *skb;
779	u32 padding_buf = 0;
780	u8 padding = ((-length) & 3);
781
782	skb = cxgbit_alloc_skb(csk, length + padding);
783	if (!skb)
784		return -ENOMEM;
785	skb_store_bits(skb, 0, login->rsp, ISCSI_HDR_LEN);
786	skb_store_bits(skb, ISCSI_HDR_LEN, login->rsp_buf, length);
787
788	if (padding)
789		skb_store_bits(skb, ISCSI_HDR_LEN + length,
790			       &padding_buf, padding);
791
792	if (login->login_complete) {
793		if (cxgbit_set_params(conn)) {
794			kfree_skb(skb);
795			return -1;
796		}
797
798		set_bit(CSK_LOGIN_DONE, &csk->com.flags);
799	}
800
801	if (cxgbit_queue_skb(csk, skb))
802		return -1;
803
804	if ((!login->login_complete) && (!login->login_failed))
805		schedule_delayed_work(&conn->login_work, 0);
806
807	return 0;
808}
809
810static void
811cxgbit_skb_copy_to_sg(struct sk_buff *skb, struct scatterlist *sg,
812		      unsigned int nents, u32 skip)
813{
814	struct skb_seq_state st;
815	const u8 *buf;
816	unsigned int consumed = 0, buf_len;
817	struct cxgbit_lro_pdu_cb *pdu_cb = cxgbit_rx_pdu_cb(skb);
818
819	skb_prepare_seq_read(skb, pdu_cb->doffset,
820			     pdu_cb->doffset + pdu_cb->dlen,
821			     &st);
822
823	while (true) {
824		buf_len = skb_seq_read(consumed, &buf, &st);
825		if (!buf_len) {
826			skb_abort_seq_read(&st);
827			break;
828		}
829
830		consumed += sg_pcopy_from_buffer(sg, nents, (void *)buf,
831						 buf_len, skip + consumed);
832	}
833}
834
835static struct iscsit_cmd *cxgbit_allocate_cmd(struct cxgbit_sock *csk)
836{
837	struct iscsit_conn *conn = csk->conn;
838	struct cxgbi_ppm *ppm = cdev2ppm(csk->com.cdev);
839	struct cxgbit_cmd *ccmd;
840	struct iscsit_cmd *cmd;
841
842	cmd = iscsit_allocate_cmd(conn, TASK_INTERRUPTIBLE);
843	if (!cmd) {
844		pr_err("Unable to allocate iscsit_cmd + cxgbit_cmd\n");
845		return NULL;
846	}
847
848	ccmd = iscsit_priv_cmd(cmd);
849	ccmd->ttinfo.tag = ppm->tformat.no_ddp_mask;
850	ccmd->setup_ddp = true;
851
852	return cmd;
853}
854
855static int
856cxgbit_handle_immediate_data(struct iscsit_cmd *cmd, struct iscsi_scsi_req *hdr,
857			     u32 length)
858{
859	struct iscsit_conn *conn = cmd->conn;
860	struct cxgbit_sock *csk = conn->context;
861	struct cxgbit_lro_pdu_cb *pdu_cb = cxgbit_rx_pdu_cb(csk->skb);
862
863	if (pdu_cb->flags & PDUCBF_RX_DCRC_ERR) {
864		pr_err("ImmediateData CRC32C DataDigest error\n");
865		if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
866			pr_err("Unable to recover from"
867			       " Immediate Data digest failure while"
868			       " in ERL=0.\n");
869			iscsit_reject_cmd(cmd, ISCSI_REASON_DATA_DIGEST_ERROR,
870					  (unsigned char *)hdr);
871			return IMMEDIATE_DATA_CANNOT_RECOVER;
872		}
873
874		iscsit_reject_cmd(cmd, ISCSI_REASON_DATA_DIGEST_ERROR,
875				  (unsigned char *)hdr);
876		return IMMEDIATE_DATA_ERL1_CRC_FAILURE;
877	}
878
879	if (cmd->se_cmd.se_cmd_flags & SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC) {
880		struct cxgbit_cmd *ccmd = iscsit_priv_cmd(cmd);
881		struct skb_shared_info *ssi = skb_shinfo(csk->skb);
882		skb_frag_t *dfrag = &ssi->frags[pdu_cb->dfrag_idx];
883
884		sg_init_table(&ccmd->sg, 1);
885		sg_set_page(&ccmd->sg, skb_frag_page(dfrag),
886				skb_frag_size(dfrag), skb_frag_off(dfrag));
887		get_page(skb_frag_page(dfrag));
888
889		cmd->se_cmd.t_data_sg = &ccmd->sg;
890		cmd->se_cmd.t_data_nents = 1;
891
892		ccmd->release = true;
893	} else {
894		struct scatterlist *sg = &cmd->se_cmd.t_data_sg[0];
895		u32 sg_nents = max(1UL, DIV_ROUND_UP(pdu_cb->dlen, PAGE_SIZE));
896
897		cxgbit_skb_copy_to_sg(csk->skb, sg, sg_nents, 0);
898	}
899
900	cmd->write_data_done += pdu_cb->dlen;
901
902	if (cmd->write_data_done == cmd->se_cmd.data_length) {
903		spin_lock_bh(&cmd->istate_lock);
904		cmd->cmd_flags |= ICF_GOT_LAST_DATAOUT;
905		cmd->i_state = ISTATE_RECEIVED_LAST_DATAOUT;
906		spin_unlock_bh(&cmd->istate_lock);
907	}
908
909	return IMMEDIATE_DATA_NORMAL_OPERATION;
910}
911
912static int
913cxgbit_get_immediate_data(struct iscsit_cmd *cmd, struct iscsi_scsi_req *hdr,
914			  bool dump_payload)
915{
916	struct iscsit_conn *conn = cmd->conn;
917	int cmdsn_ret = 0, immed_ret = IMMEDIATE_DATA_NORMAL_OPERATION;
918	/*
919	 * Special case for Unsupported SAM WRITE Opcodes and ImmediateData=Yes.
920	 */
921	if (dump_payload)
922		goto after_immediate_data;
923
924	immed_ret = cxgbit_handle_immediate_data(cmd, hdr,
925						 cmd->first_burst_len);
926after_immediate_data:
927	if (immed_ret == IMMEDIATE_DATA_NORMAL_OPERATION) {
928		/*
929		 * A PDU/CmdSN carrying Immediate Data passed
930		 * DataCRC, check against ExpCmdSN/MaxCmdSN if
931		 * Immediate Bit is not set.
932		 */
933		cmdsn_ret = iscsit_sequence_cmd(conn, cmd,
934						(unsigned char *)hdr,
935						hdr->cmdsn);
936		if (cmdsn_ret == CMDSN_ERROR_CANNOT_RECOVER)
937			return -1;
938
939		if (cmd->sense_reason || cmdsn_ret == CMDSN_LOWER_THAN_EXP) {
940			target_put_sess_cmd(&cmd->se_cmd);
941			return 0;
942		} else if (cmd->unsolicited_data) {
943			iscsit_set_unsolicited_dataout(cmd);
944		}
945
946	} else if (immed_ret == IMMEDIATE_DATA_ERL1_CRC_FAILURE) {
947		/*
948		 * Immediate Data failed DataCRC and ERL>=1,
949		 * silently drop this PDU and let the initiator
950		 * plug the CmdSN gap.
951		 *
952		 * FIXME: Send Unsolicited NOPIN with reserved
953		 * TTT here to help the initiator figure out
954		 * the missing CmdSN, although they should be
955		 * intelligent enough to determine the missing
956		 * CmdSN and issue a retry to plug the sequence.
957		 */
958		cmd->i_state = ISTATE_REMOVE;
959		iscsit_add_cmd_to_immediate_queue(cmd, conn, cmd->i_state);
960	} else /* immed_ret == IMMEDIATE_DATA_CANNOT_RECOVER */
961		return -1;
962
963	return 0;
964}
965
966static int
967cxgbit_handle_scsi_cmd(struct cxgbit_sock *csk, struct iscsit_cmd *cmd)
968{
969	struct iscsit_conn *conn = csk->conn;
970	struct cxgbit_lro_pdu_cb *pdu_cb = cxgbit_rx_pdu_cb(csk->skb);
971	struct iscsi_scsi_req *hdr = (struct iscsi_scsi_req *)pdu_cb->hdr;
972	int rc;
973	bool dump_payload = false;
974
975	rc = iscsit_setup_scsi_cmd(conn, cmd, (unsigned char *)hdr);
976	if (rc < 0)
977		return rc;
978
979	if (pdu_cb->dlen && (pdu_cb->dlen == cmd->se_cmd.data_length) &&
980	    (pdu_cb->nr_dfrags == 1))
981		cmd->se_cmd.se_cmd_flags |= SCF_PASSTHROUGH_SG_TO_MEM_NOALLOC;
982
983	rc = iscsit_process_scsi_cmd(conn, cmd, hdr);
984	if (rc < 0)
985		return 0;
986	else if (rc > 0)
987		dump_payload = true;
988
989	if (!pdu_cb->dlen)
990		return 0;
991
992	return cxgbit_get_immediate_data(cmd, hdr, dump_payload);
993}
994
995static int cxgbit_handle_iscsi_dataout(struct cxgbit_sock *csk)
996{
997	struct scatterlist *sg_start;
998	struct iscsit_conn *conn = csk->conn;
999	struct iscsit_cmd *cmd = NULL;
1000	struct cxgbit_cmd *ccmd;
1001	struct cxgbi_task_tag_info *ttinfo;
1002	struct cxgbit_lro_pdu_cb *pdu_cb = cxgbit_rx_pdu_cb(csk->skb);
1003	struct iscsi_data *hdr = (struct iscsi_data *)pdu_cb->hdr;
1004	u32 data_offset = be32_to_cpu(hdr->offset);
1005	u32 data_len = ntoh24(hdr->dlength);
1006	int rc, sg_nents, sg_off;
1007	bool dcrc_err = false;
1008
1009	if (pdu_cb->flags & PDUCBF_RX_DDP_CMP) {
1010		u32 offset = be32_to_cpu(hdr->offset);
1011		u32 ddp_data_len;
1012		bool success = false;
1013
1014		cmd = iscsit_find_cmd_from_itt_or_dump(conn, hdr->itt, 0);
1015		if (!cmd)
1016			return 0;
1017
1018		ddp_data_len = offset - cmd->write_data_done;
1019		atomic_long_add(ddp_data_len, &conn->sess->rx_data_octets);
1020
1021		cmd->write_data_done = offset;
1022		cmd->next_burst_len = ddp_data_len;
1023		cmd->data_sn = be32_to_cpu(hdr->datasn);
1024
1025		rc = __iscsit_check_dataout_hdr(conn, (unsigned char *)hdr,
1026						cmd, data_len, &success);
1027		if (rc < 0)
1028			return rc;
1029		else if (!success)
1030			return 0;
1031	} else {
1032		rc = iscsit_check_dataout_hdr(conn, (unsigned char *)hdr, &cmd);
1033		if (rc < 0)
1034			return rc;
1035		else if (!cmd)
1036			return 0;
1037	}
1038
1039	if (pdu_cb->flags & PDUCBF_RX_DCRC_ERR) {
1040		pr_err("ITT: 0x%08x, Offset: %u, Length: %u,"
1041		       " DataSN: 0x%08x\n",
1042		       hdr->itt, hdr->offset, data_len,
1043		       hdr->datasn);
1044
1045		dcrc_err = true;
1046		goto check_payload;
1047	}
1048
1049	pr_debug("DataOut data_len: %u, "
1050		"write_data_done: %u, data_length: %u\n",
1051		  data_len,  cmd->write_data_done,
1052		  cmd->se_cmd.data_length);
1053
1054	if (!(pdu_cb->flags & PDUCBF_RX_DATA_DDPD)) {
1055		u32 skip = data_offset % PAGE_SIZE;
1056
1057		sg_off = data_offset / PAGE_SIZE;
1058		sg_start = &cmd->se_cmd.t_data_sg[sg_off];
1059		sg_nents = max(1UL, DIV_ROUND_UP(skip + data_len, PAGE_SIZE));
1060
1061		cxgbit_skb_copy_to_sg(csk->skb, sg_start, sg_nents, skip);
1062	}
1063
1064	ccmd = iscsit_priv_cmd(cmd);
1065	ttinfo = &ccmd->ttinfo;
1066
1067	if (ccmd->release && ttinfo->sgl &&
1068	    (cmd->se_cmd.data_length ==	(cmd->write_data_done + data_len))) {
1069		struct cxgbit_device *cdev = csk->com.cdev;
1070		struct cxgbi_ppm *ppm = cdev2ppm(cdev);
1071
1072		dma_unmap_sg(&ppm->pdev->dev, ttinfo->sgl, ttinfo->nents,
1073			     DMA_FROM_DEVICE);
1074		ttinfo->nents = 0;
1075		ttinfo->sgl = NULL;
1076	}
1077
1078check_payload:
1079
1080	rc = iscsit_check_dataout_payload(cmd, hdr, dcrc_err);
1081	if (rc < 0)
1082		return rc;
1083
1084	return 0;
1085}
1086
1087static int cxgbit_handle_nop_out(struct cxgbit_sock *csk, struct iscsit_cmd *cmd)
1088{
1089	struct iscsit_conn *conn = csk->conn;
1090	struct cxgbit_lro_pdu_cb *pdu_cb = cxgbit_rx_pdu_cb(csk->skb);
1091	struct iscsi_nopout *hdr = (struct iscsi_nopout *)pdu_cb->hdr;
1092	unsigned char *ping_data = NULL;
1093	u32 payload_length = pdu_cb->dlen;
1094	int ret;
1095
1096	ret = iscsit_setup_nop_out(conn, cmd, hdr);
1097	if (ret < 0)
1098		return 0;
1099
1100	if (pdu_cb->flags & PDUCBF_RX_DCRC_ERR) {
1101		if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
1102			pr_err("Unable to recover from"
1103			       " NOPOUT Ping DataCRC failure while in"
1104			       " ERL=0.\n");
1105			ret = -1;
1106			goto out;
1107		} else {
1108			/*
1109			 * drop this PDU and let the
1110			 * initiator plug the CmdSN gap.
1111			 */
1112			pr_info("Dropping NOPOUT"
1113				" Command CmdSN: 0x%08x due to"
1114				" DataCRC error.\n", hdr->cmdsn);
1115			ret = 0;
1116			goto out;
1117		}
1118	}
1119
1120	/*
1121	 * Handle NOP-OUT payload for traditional iSCSI sockets
1122	 */
1123	if (payload_length && hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
1124		ping_data = kzalloc(payload_length + 1, GFP_KERNEL);
1125		if (!ping_data) {
1126			pr_err("Unable to allocate memory for"
1127				" NOPOUT ping data.\n");
1128			ret = -1;
1129			goto out;
1130		}
1131
1132		skb_copy_bits(csk->skb, pdu_cb->doffset,
1133			      ping_data, payload_length);
1134
1135		ping_data[payload_length] = '\0';
1136		/*
1137		 * Attach ping data to struct iscsit_cmd->buf_ptr.
1138		 */
1139		cmd->buf_ptr = ping_data;
1140		cmd->buf_ptr_size = payload_length;
1141
1142		pr_debug("Got %u bytes of NOPOUT ping"
1143			" data.\n", payload_length);
1144		pr_debug("Ping Data: \"%s\"\n", ping_data);
1145	}
1146
1147	return iscsit_process_nop_out(conn, cmd, hdr);
1148out:
1149	if (cmd)
1150		iscsit_free_cmd(cmd, false);
1151	return ret;
1152}
1153
1154static int
1155cxgbit_handle_text_cmd(struct cxgbit_sock *csk, struct iscsit_cmd *cmd)
1156{
1157	struct iscsit_conn *conn = csk->conn;
1158	struct cxgbit_lro_pdu_cb *pdu_cb = cxgbit_rx_pdu_cb(csk->skb);
1159	struct iscsi_text *hdr = (struct iscsi_text *)pdu_cb->hdr;
1160	u32 payload_length = pdu_cb->dlen;
1161	int rc;
1162	unsigned char *text_in = NULL;
1163
1164	rc = iscsit_setup_text_cmd(conn, cmd, hdr);
1165	if (rc < 0)
1166		return rc;
1167
1168	if (pdu_cb->flags & PDUCBF_RX_DCRC_ERR) {
1169		if (!conn->sess->sess_ops->ErrorRecoveryLevel) {
1170			pr_err("Unable to recover from"
1171			       " Text Data digest failure while in"
1172			       " ERL=0.\n");
1173			goto reject;
1174		} else {
1175			/*
1176			 * drop this PDU and let the
1177			 * initiator plug the CmdSN gap.
1178			 */
1179			pr_info("Dropping Text"
1180				" Command CmdSN: 0x%08x due to"
1181				" DataCRC error.\n", hdr->cmdsn);
1182			return 0;
1183		}
1184	}
1185
1186	if (payload_length) {
1187		text_in = kzalloc(payload_length, GFP_KERNEL);
1188		if (!text_in) {
1189			pr_err("Unable to allocate text_in of payload_length: %u\n",
1190			       payload_length);
1191			return -ENOMEM;
1192		}
1193		skb_copy_bits(csk->skb, pdu_cb->doffset,
1194			      text_in, payload_length);
1195
1196		text_in[payload_length - 1] = '\0';
1197
1198		cmd->text_in_ptr = text_in;
1199	}
1200
1201	return iscsit_process_text_cmd(conn, cmd, hdr);
1202
1203reject:
1204	return iscsit_reject_cmd(cmd, ISCSI_REASON_PROTOCOL_ERROR,
1205				 pdu_cb->hdr);
1206}
1207
1208static int cxgbit_target_rx_opcode(struct cxgbit_sock *csk)
1209{
1210	struct cxgbit_lro_pdu_cb *pdu_cb = cxgbit_rx_pdu_cb(csk->skb);
1211	struct iscsi_hdr *hdr = (struct iscsi_hdr *)pdu_cb->hdr;
1212	struct iscsit_conn *conn = csk->conn;
1213	struct iscsit_cmd *cmd = NULL;
1214	u8 opcode = (hdr->opcode & ISCSI_OPCODE_MASK);
1215	int ret = -EINVAL;
1216
1217	switch (opcode) {
1218	case ISCSI_OP_SCSI_CMD:
1219		cmd = cxgbit_allocate_cmd(csk);
1220		if (!cmd)
1221			goto reject;
1222
1223		ret = cxgbit_handle_scsi_cmd(csk, cmd);
1224		break;
1225	case ISCSI_OP_SCSI_DATA_OUT:
1226		ret = cxgbit_handle_iscsi_dataout(csk);
1227		break;
1228	case ISCSI_OP_NOOP_OUT:
1229		if (hdr->ttt == cpu_to_be32(0xFFFFFFFF)) {
1230			cmd = cxgbit_allocate_cmd(csk);
1231			if (!cmd)
1232				goto reject;
1233		}
1234
1235		ret = cxgbit_handle_nop_out(csk, cmd);
1236		break;
1237	case ISCSI_OP_SCSI_TMFUNC:
1238		cmd = cxgbit_allocate_cmd(csk);
1239		if (!cmd)
1240			goto reject;
1241
1242		ret = iscsit_handle_task_mgt_cmd(conn, cmd,
1243						 (unsigned char *)hdr);
1244		break;
1245	case ISCSI_OP_TEXT:
1246		if (hdr->ttt != cpu_to_be32(0xFFFFFFFF)) {
1247			cmd = iscsit_find_cmd_from_itt(conn, hdr->itt);
1248			if (!cmd)
1249				goto reject;
1250		} else {
1251			cmd = cxgbit_allocate_cmd(csk);
1252			if (!cmd)
1253				goto reject;
1254		}
1255
1256		ret = cxgbit_handle_text_cmd(csk, cmd);
1257		break;
1258	case ISCSI_OP_LOGOUT:
1259		cmd = cxgbit_allocate_cmd(csk);
1260		if (!cmd)
1261			goto reject;
1262
1263		ret = iscsit_handle_logout_cmd(conn, cmd, (unsigned char *)hdr);
1264		if (ret > 0)
1265			wait_for_completion_timeout(&conn->conn_logout_comp,
1266						    SECONDS_FOR_LOGOUT_COMP
1267						    * HZ);
1268		break;
1269	case ISCSI_OP_SNACK:
1270		ret = iscsit_handle_snack(conn, (unsigned char *)hdr);
1271		break;
1272	default:
1273		pr_err("Got unknown iSCSI OpCode: 0x%02x\n", opcode);
1274		dump_stack();
1275		break;
1276	}
1277
1278	return ret;
1279
1280reject:
1281	return iscsit_add_reject(conn, ISCSI_REASON_BOOKMARK_NO_RESOURCES,
1282				 (unsigned char *)hdr);
1283	return ret;
1284}
1285
1286static int cxgbit_rx_opcode(struct cxgbit_sock *csk)
1287{
1288	struct cxgbit_lro_pdu_cb *pdu_cb = cxgbit_rx_pdu_cb(csk->skb);
1289	struct iscsit_conn *conn = csk->conn;
1290	struct iscsi_hdr *hdr = pdu_cb->hdr;
1291	u8 opcode;
1292
1293	if (pdu_cb->flags & PDUCBF_RX_HCRC_ERR) {
1294		atomic_long_inc(&conn->sess->conn_digest_errors);
1295		goto transport_err;
1296	}
1297
1298	if (conn->conn_state == TARG_CONN_STATE_IN_LOGOUT)
1299		goto transport_err;
1300
1301	opcode = hdr->opcode & ISCSI_OPCODE_MASK;
1302
1303	if (conn->sess->sess_ops->SessionType &&
1304	    ((!(opcode & ISCSI_OP_TEXT)) ||
1305	     (!(opcode & ISCSI_OP_LOGOUT)))) {
1306		pr_err("Received illegal iSCSI Opcode: 0x%02x"
1307			" while in Discovery Session, rejecting.\n", opcode);
1308		iscsit_add_reject(conn, ISCSI_REASON_PROTOCOL_ERROR,
1309				  (unsigned char *)hdr);
1310		goto transport_err;
1311	}
1312
1313	if (cxgbit_target_rx_opcode(csk) < 0)
1314		goto transport_err;
1315
1316	return 0;
1317
1318transport_err:
1319	return -1;
1320}
1321
1322static int cxgbit_rx_login_pdu(struct cxgbit_sock *csk)
1323{
1324	struct iscsit_conn *conn = csk->conn;
1325	struct iscsi_login *login = conn->login;
1326	struct cxgbit_lro_pdu_cb *pdu_cb = cxgbit_rx_pdu_cb(csk->skb);
1327	struct iscsi_login_req *login_req;
1328
1329	login_req = (struct iscsi_login_req *)login->req;
1330	memcpy(login_req, pdu_cb->hdr, sizeof(*login_req));
1331
1332	pr_debug("Got Login Command, Flags 0x%02x, ITT: 0x%08x,"
1333		" CmdSN: 0x%08x, ExpStatSN: 0x%08x, CID: %hu, Length: %u\n",
1334		login_req->flags, login_req->itt, login_req->cmdsn,
1335		login_req->exp_statsn, login_req->cid, pdu_cb->dlen);
1336	/*
1337	 * Setup the initial iscsi_login values from the leading
1338	 * login request PDU.
1339	 */
1340	if (login->first_request) {
1341		login_req = (struct iscsi_login_req *)login->req;
1342		login->leading_connection = (!login_req->tsih) ? 1 : 0;
1343		login->current_stage	= ISCSI_LOGIN_CURRENT_STAGE(
1344				login_req->flags);
1345		login->version_min	= login_req->min_version;
1346		login->version_max	= login_req->max_version;
1347		memcpy(login->isid, login_req->isid, 6);
1348		login->cmd_sn		= be32_to_cpu(login_req->cmdsn);
1349		login->init_task_tag	= login_req->itt;
1350		login->initial_exp_statsn = be32_to_cpu(login_req->exp_statsn);
1351		login->cid		= be16_to_cpu(login_req->cid);
1352		login->tsih		= be16_to_cpu(login_req->tsih);
1353	}
1354
1355	if (iscsi_target_check_login_request(conn, login) < 0)
1356		return -1;
1357
1358	memset(login->req_buf, 0, MAX_KEY_VALUE_PAIRS);
1359	skb_copy_bits(csk->skb, pdu_cb->doffset, login->req_buf, pdu_cb->dlen);
1360
1361	return 0;
1362}
1363
1364static int
1365cxgbit_process_iscsi_pdu(struct cxgbit_sock *csk, struct sk_buff *skb, int idx)
1366{
1367	struct cxgbit_lro_pdu_cb *pdu_cb = cxgbit_skb_lro_pdu_cb(skb, idx);
1368	int ret;
1369
1370	cxgbit_rx_pdu_cb(skb) = pdu_cb;
1371
1372	csk->skb = skb;
1373
1374	if (!test_bit(CSK_LOGIN_DONE, &csk->com.flags)) {
1375		ret = cxgbit_rx_login_pdu(csk);
1376		set_bit(CSK_LOGIN_PDU_DONE, &csk->com.flags);
1377	} else {
1378		ret = cxgbit_rx_opcode(csk);
1379	}
1380
1381	return ret;
1382}
1383
1384static void cxgbit_lro_skb_dump(struct sk_buff *skb)
1385{
1386	struct skb_shared_info *ssi = skb_shinfo(skb);
1387	struct cxgbit_lro_cb *lro_cb = cxgbit_skb_lro_cb(skb);
1388	struct cxgbit_lro_pdu_cb *pdu_cb = cxgbit_skb_lro_pdu_cb(skb, 0);
1389	u8 i;
1390
1391	pr_info("skb 0x%p, head 0x%p, 0x%p, len %u,%u, frags %u.\n",
1392		skb, skb->head, skb->data, skb->len, skb->data_len,
1393		ssi->nr_frags);
1394	pr_info("skb 0x%p, lro_cb, csk 0x%p, pdu %u, %u.\n",
1395		skb, lro_cb->csk, lro_cb->pdu_idx, lro_cb->pdu_totallen);
1396
1397	for (i = 0; i < lro_cb->pdu_idx; i++, pdu_cb++)
1398		pr_info("skb 0x%p, pdu %d, %u, f 0x%x, seq 0x%x, dcrc 0x%x, "
1399			"frags %u.\n",
1400			skb, i, pdu_cb->pdulen, pdu_cb->flags, pdu_cb->seq,
1401			pdu_cb->ddigest, pdu_cb->frags);
1402	for (i = 0; i < ssi->nr_frags; i++)
1403		pr_info("skb 0x%p, frag %d, off %u, sz %u.\n",
1404			skb, i, skb_frag_off(&ssi->frags[i]),
1405			skb_frag_size(&ssi->frags[i]));
1406}
1407
1408static void cxgbit_lro_hskb_reset(struct cxgbit_sock *csk)
1409{
1410	struct sk_buff *skb = csk->lro_hskb;
1411	struct skb_shared_info *ssi = skb_shinfo(skb);
1412	u8 i;
1413
1414	memset(skb->data, 0, LRO_SKB_MIN_HEADROOM);
1415	for (i = 0; i < ssi->nr_frags; i++)
1416		put_page(skb_frag_page(&ssi->frags[i]));
1417	ssi->nr_frags = 0;
1418	skb->data_len = 0;
1419	skb->truesize -= skb->len;
1420	skb->len = 0;
1421}
1422
1423static void
1424cxgbit_lro_skb_merge(struct cxgbit_sock *csk, struct sk_buff *skb, u8 pdu_idx)
1425{
1426	struct sk_buff *hskb = csk->lro_hskb;
1427	struct cxgbit_lro_pdu_cb *hpdu_cb = cxgbit_skb_lro_pdu_cb(hskb, 0);
1428	struct cxgbit_lro_pdu_cb *pdu_cb = cxgbit_skb_lro_pdu_cb(skb, pdu_idx);
1429	struct skb_shared_info *hssi = skb_shinfo(hskb);
1430	struct skb_shared_info *ssi = skb_shinfo(skb);
1431	unsigned int len = 0;
1432
1433	if (pdu_cb->flags & PDUCBF_RX_HDR) {
1434		u8 hfrag_idx = hssi->nr_frags;
1435
1436		hpdu_cb->flags |= pdu_cb->flags;
1437		hpdu_cb->seq = pdu_cb->seq;
1438		hpdu_cb->hdr = pdu_cb->hdr;
1439		hpdu_cb->hlen = pdu_cb->hlen;
1440
1441		memcpy(&hssi->frags[hfrag_idx], &ssi->frags[pdu_cb->hfrag_idx],
1442		       sizeof(skb_frag_t));
1443
1444		get_page(skb_frag_page(&hssi->frags[hfrag_idx]));
1445		hssi->nr_frags++;
1446		hpdu_cb->frags++;
1447		hpdu_cb->hfrag_idx = hfrag_idx;
1448
1449		len = skb_frag_size(&hssi->frags[hfrag_idx]);
1450		hskb->len += len;
1451		hskb->data_len += len;
1452		hskb->truesize += len;
1453	}
1454
1455	if (pdu_cb->flags & PDUCBF_RX_DATA) {
1456		u8 dfrag_idx = hssi->nr_frags, i;
1457
1458		hpdu_cb->flags |= pdu_cb->flags;
1459		hpdu_cb->dfrag_idx = dfrag_idx;
1460
1461		len = 0;
1462		for (i = 0; i < pdu_cb->nr_dfrags; dfrag_idx++, i++) {
1463			memcpy(&hssi->frags[dfrag_idx],
1464			       &ssi->frags[pdu_cb->dfrag_idx + i],
1465			       sizeof(skb_frag_t));
1466
1467			get_page(skb_frag_page(&hssi->frags[dfrag_idx]));
1468
1469			len += skb_frag_size(&hssi->frags[dfrag_idx]);
1470
1471			hssi->nr_frags++;
1472			hpdu_cb->frags++;
1473		}
1474
1475		hpdu_cb->dlen = pdu_cb->dlen;
1476		hpdu_cb->doffset = hpdu_cb->hlen;
1477		hpdu_cb->nr_dfrags = pdu_cb->nr_dfrags;
1478		hskb->len += len;
1479		hskb->data_len += len;
1480		hskb->truesize += len;
1481	}
1482
1483	if (pdu_cb->flags & PDUCBF_RX_STATUS) {
1484		hpdu_cb->flags |= pdu_cb->flags;
1485
1486		if (hpdu_cb->flags & PDUCBF_RX_DATA)
1487			hpdu_cb->flags &= ~PDUCBF_RX_DATA_DDPD;
1488
1489		hpdu_cb->ddigest = pdu_cb->ddigest;
1490		hpdu_cb->pdulen = pdu_cb->pdulen;
1491	}
1492}
1493
1494static int cxgbit_process_lro_skb(struct cxgbit_sock *csk, struct sk_buff *skb)
1495{
1496	struct cxgbit_lro_cb *lro_cb = cxgbit_skb_lro_cb(skb);
1497	struct cxgbit_lro_pdu_cb *pdu_cb = cxgbit_skb_lro_pdu_cb(skb, 0);
1498	u8 pdu_idx = 0, last_idx = 0;
1499	int ret = 0;
1500
1501	if (!pdu_cb->complete) {
1502		cxgbit_lro_skb_merge(csk, skb, 0);
1503
1504		if (pdu_cb->flags & PDUCBF_RX_STATUS) {
1505			struct sk_buff *hskb = csk->lro_hskb;
1506
1507			ret = cxgbit_process_iscsi_pdu(csk, hskb, 0);
1508
1509			cxgbit_lro_hskb_reset(csk);
1510
1511			if (ret < 0)
1512				goto out;
1513		}
1514
1515		pdu_idx = 1;
1516	}
1517
1518	if (lro_cb->pdu_idx)
1519		last_idx = lro_cb->pdu_idx - 1;
1520
1521	for (; pdu_idx <= last_idx; pdu_idx++) {
1522		ret = cxgbit_process_iscsi_pdu(csk, skb, pdu_idx);
1523		if (ret < 0)
1524			goto out;
1525	}
1526
1527	if ((!lro_cb->complete) && lro_cb->pdu_idx)
1528		cxgbit_lro_skb_merge(csk, skb, lro_cb->pdu_idx);
1529
1530out:
1531	return ret;
1532}
1533
1534static int cxgbit_t5_rx_lro_skb(struct cxgbit_sock *csk, struct sk_buff *skb)
1535{
1536	struct cxgbit_lro_cb *lro_cb = cxgbit_skb_lro_cb(skb);
1537	struct cxgbit_lro_pdu_cb *pdu_cb = cxgbit_skb_lro_pdu_cb(skb, 0);
1538	int ret = -1;
1539
1540	if ((pdu_cb->flags & PDUCBF_RX_HDR) &&
1541	    (pdu_cb->seq != csk->rcv_nxt)) {
1542		pr_info("csk 0x%p, tid 0x%x, seq 0x%x != 0x%x.\n",
1543			csk, csk->tid, pdu_cb->seq, csk->rcv_nxt);
1544		cxgbit_lro_skb_dump(skb);
1545		return ret;
1546	}
1547
1548	csk->rcv_nxt += lro_cb->pdu_totallen;
1549
1550	ret = cxgbit_process_lro_skb(csk, skb);
1551
1552	csk->rx_credits += lro_cb->pdu_totallen;
1553
1554	if (csk->rx_credits >= (csk->rcv_win / 4))
1555		cxgbit_rx_data_ack(csk);
1556
1557	return ret;
1558}
1559
1560static int cxgbit_rx_lro_skb(struct cxgbit_sock *csk, struct sk_buff *skb)
1561{
1562	struct cxgbit_lro_cb *lro_cb = cxgbit_skb_lro_cb(skb);
1563	int ret;
1564
1565	ret = cxgbit_process_lro_skb(csk, skb);
1566	if (ret)
1567		return ret;
1568
1569	csk->rx_credits += lro_cb->pdu_totallen;
1570	if (csk->rx_credits >= csk->rcv_win) {
1571		csk->rx_credits = 0;
1572		cxgbit_rx_data_ack(csk);
1573	}
1574
1575	return 0;
1576}
1577
1578static int cxgbit_rx_skb(struct cxgbit_sock *csk, struct sk_buff *skb)
1579{
1580	struct cxgb4_lld_info *lldi = &csk->com.cdev->lldi;
1581	int ret = -1;
1582
1583	if (likely(cxgbit_skcb_flags(skb) & SKCBF_RX_LRO)) {
1584		if (is_t5(lldi->adapter_type))
1585			ret = cxgbit_t5_rx_lro_skb(csk, skb);
1586		else
1587			ret = cxgbit_rx_lro_skb(csk, skb);
1588	}
1589
1590	__kfree_skb(skb);
1591	return ret;
1592}
1593
1594static bool cxgbit_rxq_len(struct cxgbit_sock *csk, struct sk_buff_head *rxq)
1595{
1596	spin_lock_bh(&csk->rxq.lock);
1597	if (skb_queue_len(&csk->rxq)) {
1598		skb_queue_splice_init(&csk->rxq, rxq);
1599		spin_unlock_bh(&csk->rxq.lock);
1600		return true;
1601	}
1602	spin_unlock_bh(&csk->rxq.lock);
1603	return false;
1604}
1605
1606static int cxgbit_wait_rxq(struct cxgbit_sock *csk)
1607{
1608	struct sk_buff *skb;
1609	struct sk_buff_head rxq;
1610
1611	skb_queue_head_init(&rxq);
1612
1613	wait_event_interruptible(csk->waitq, cxgbit_rxq_len(csk, &rxq));
1614
1615	if (signal_pending(current))
1616		goto out;
1617
1618	while ((skb = __skb_dequeue(&rxq))) {
1619		if (cxgbit_rx_skb(csk, skb))
1620			goto out;
1621	}
1622
1623	return 0;
1624out:
1625	__skb_queue_purge(&rxq);
1626	return -1;
1627}
1628
1629int cxgbit_get_login_rx(struct iscsit_conn *conn, struct iscsi_login *login)
1630{
1631	struct cxgbit_sock *csk = conn->context;
1632	int ret = -1;
1633
1634	while (!test_and_clear_bit(CSK_LOGIN_PDU_DONE, &csk->com.flags)) {
1635		ret = cxgbit_wait_rxq(csk);
1636		if (ret) {
1637			clear_bit(CSK_LOGIN_PDU_DONE, &csk->com.flags);
1638			break;
1639		}
1640	}
1641
1642	return ret;
1643}
1644
1645void cxgbit_get_rx_pdu(struct iscsit_conn *conn)
1646{
1647	struct cxgbit_sock *csk = conn->context;
1648
1649	while (!kthread_should_stop()) {
1650		iscsit_thread_check_cpumask(conn, current, 0);
1651		if (cxgbit_wait_rxq(csk))
1652			return;
1653	}
1654}
1655