1/*
2 * Copyright (c) 2004, 2005, 2006 Voltaire, Inc. All rights reserved.
3 * Copyright (c) 2013-2014 Mellanox Technologies. All rights reserved.
4 *
5 * This software is available to you under a choice of one of two
6 * licenses.  You may choose to be licensed under the terms of the GNU
7 * General Public License (GPL) Version 2, available from the file
8 * COPYING in the main directory of this source tree, or the
9 * OpenIB.org BSD license below:
10 *
11 *     Redistribution and use in source and binary forms, with or
12 *     without modification, are permitted provided that the following
13 *     conditions are met:
14 *
15 *	- Redistributions of source code must retain the above
16 *	  copyright notice, this list of conditions and the following
17 *	  disclaimer.
18 *
19 *	- Redistributions in binary form must reproduce the above
20 *	  copyright notice, this list of conditions and the following
21 *	  disclaimer in the documentation and/or other materials
22 *	  provided with the distribution.
23 *
24 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
25 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
26 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
27 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
28 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
29 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
30 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
31 * SOFTWARE.
32 */
33#include <linux/kernel.h>
34#include <linux/slab.h>
35#include <linux/mm.h>
36#include <linux/scatterlist.h>
37#include <linux/kfifo.h>
38#include <scsi/scsi_cmnd.h>
39#include <scsi/scsi_host.h>
40
41#include "iscsi_iser.h"
42
43/* Register user buffer memory and initialize passive rdma
44 *  dto descriptor. Data size is stored in
45 *  task->data[ISER_DIR_IN].data_len, Protection size
46 *  os stored in task->prot[ISER_DIR_IN].data_len
47 */
48static int iser_prepare_read_cmd(struct iscsi_task *task)
49
50{
51	struct iscsi_iser_task *iser_task = task->dd_data;
52	struct iser_mem_reg *mem_reg;
53	int err;
54	struct iser_ctrl *hdr = &iser_task->desc.iser_header;
55	struct iser_data_buf *buf_in = &iser_task->data[ISER_DIR_IN];
56
57	err = iser_dma_map_task_data(iser_task,
58				     buf_in,
59				     ISER_DIR_IN,
60				     DMA_FROM_DEVICE);
61	if (err)
62		return err;
63
64	if (scsi_prot_sg_count(iser_task->sc)) {
65		struct iser_data_buf *pbuf_in = &iser_task->prot[ISER_DIR_IN];
66
67		err = iser_dma_map_task_data(iser_task,
68					     pbuf_in,
69					     ISER_DIR_IN,
70					     DMA_FROM_DEVICE);
71		if (err)
72			return err;
73	}
74
75	err = iser_reg_mem_fastreg(iser_task, ISER_DIR_IN, false);
76	if (err) {
77		iser_err("Failed to set up Data-IN RDMA\n");
78		return err;
79	}
80	mem_reg = &iser_task->rdma_reg[ISER_DIR_IN];
81
82	hdr->flags    |= ISER_RSV;
83	hdr->read_stag = cpu_to_be32(mem_reg->rkey);
84	hdr->read_va   = cpu_to_be64(mem_reg->sge.addr);
85
86	iser_dbg("Cmd itt:%d READ tags RKEY:%#.4X VA:%#llX\n",
87		 task->itt, mem_reg->rkey,
88		 (unsigned long long)mem_reg->sge.addr);
89
90	return 0;
91}
92
93/* Register user buffer memory and initialize passive rdma
94 *  dto descriptor. Data size is stored in
95 *  task->data[ISER_DIR_OUT].data_len, Protection size
96 *  is stored at task->prot[ISER_DIR_OUT].data_len
97 */
98static int
99iser_prepare_write_cmd(struct iscsi_task *task,
100		       unsigned int imm_sz,
101		       unsigned int unsol_sz,
102		       unsigned int edtl)
103{
104	struct iscsi_iser_task *iser_task = task->dd_data;
105	struct iser_mem_reg *mem_reg;
106	int err;
107	struct iser_ctrl *hdr = &iser_task->desc.iser_header;
108	struct iser_data_buf *buf_out = &iser_task->data[ISER_DIR_OUT];
109	struct ib_sge *tx_dsg = &iser_task->desc.tx_sg[1];
110
111	err = iser_dma_map_task_data(iser_task,
112				     buf_out,
113				     ISER_DIR_OUT,
114				     DMA_TO_DEVICE);
115	if (err)
116		return err;
117
118	if (scsi_prot_sg_count(iser_task->sc)) {
119		struct iser_data_buf *pbuf_out = &iser_task->prot[ISER_DIR_OUT];
120
121		err = iser_dma_map_task_data(iser_task,
122					     pbuf_out,
123					     ISER_DIR_OUT,
124					     DMA_TO_DEVICE);
125		if (err)
126			return err;
127	}
128
129	err = iser_reg_mem_fastreg(iser_task, ISER_DIR_OUT,
130				   buf_out->data_len == imm_sz);
131	if (err != 0) {
132		iser_err("Failed to register write cmd RDMA mem\n");
133		return err;
134	}
135
136	mem_reg = &iser_task->rdma_reg[ISER_DIR_OUT];
137
138	if (unsol_sz < edtl) {
139		hdr->flags     |= ISER_WSV;
140		if (buf_out->data_len > imm_sz) {
141			hdr->write_stag = cpu_to_be32(mem_reg->rkey);
142			hdr->write_va = cpu_to_be64(mem_reg->sge.addr + unsol_sz);
143		}
144
145		iser_dbg("Cmd itt:%d, WRITE tags, RKEY:%#.4X VA:%#llX + unsol:%d\n",
146			 task->itt, mem_reg->rkey,
147			 (unsigned long long)mem_reg->sge.addr, unsol_sz);
148	}
149
150	if (imm_sz > 0) {
151		iser_dbg("Cmd itt:%d, WRITE, adding imm.data sz: %d\n",
152			 task->itt, imm_sz);
153		tx_dsg->addr = mem_reg->sge.addr;
154		tx_dsg->length = imm_sz;
155		tx_dsg->lkey = mem_reg->sge.lkey;
156		iser_task->desc.num_sge = 2;
157	}
158
159	return 0;
160}
161
162/* creates a new tx descriptor and adds header regd buffer */
163static void iser_create_send_desc(struct iser_conn	*iser_conn,
164				  struct iser_tx_desc	*tx_desc)
165{
166	struct iser_device *device = iser_conn->ib_conn.device;
167
168	ib_dma_sync_single_for_cpu(device->ib_device,
169		tx_desc->dma_addr, ISER_HEADERS_LEN, DMA_TO_DEVICE);
170
171	memset(&tx_desc->iser_header, 0, sizeof(struct iser_ctrl));
172	tx_desc->iser_header.flags = ISER_VER;
173	tx_desc->num_sge = 1;
174}
175
176static void iser_free_login_buf(struct iser_conn *iser_conn)
177{
178	struct iser_device *device = iser_conn->ib_conn.device;
179	struct iser_login_desc *desc = &iser_conn->login_desc;
180
181	if (!desc->req)
182		return;
183
184	ib_dma_unmap_single(device->ib_device, desc->req_dma,
185			    ISCSI_DEF_MAX_RECV_SEG_LEN, DMA_TO_DEVICE);
186
187	ib_dma_unmap_single(device->ib_device, desc->rsp_dma,
188			    ISER_RX_LOGIN_SIZE, DMA_FROM_DEVICE);
189
190	kfree(desc->req);
191	kfree(desc->rsp);
192
193	/* make sure we never redo any unmapping */
194	desc->req = NULL;
195	desc->rsp = NULL;
196}
197
198static int iser_alloc_login_buf(struct iser_conn *iser_conn)
199{
200	struct iser_device *device = iser_conn->ib_conn.device;
201	struct iser_login_desc *desc = &iser_conn->login_desc;
202
203	desc->req = kmalloc(ISCSI_DEF_MAX_RECV_SEG_LEN, GFP_KERNEL);
204	if (!desc->req)
205		return -ENOMEM;
206
207	desc->req_dma = ib_dma_map_single(device->ib_device, desc->req,
208					  ISCSI_DEF_MAX_RECV_SEG_LEN,
209					  DMA_TO_DEVICE);
210	if (ib_dma_mapping_error(device->ib_device,
211				desc->req_dma))
212		goto free_req;
213
214	desc->rsp = kmalloc(ISER_RX_LOGIN_SIZE, GFP_KERNEL);
215	if (!desc->rsp)
216		goto unmap_req;
217
218	desc->rsp_dma = ib_dma_map_single(device->ib_device, desc->rsp,
219					   ISER_RX_LOGIN_SIZE,
220					   DMA_FROM_DEVICE);
221	if (ib_dma_mapping_error(device->ib_device,
222				desc->rsp_dma))
223		goto free_rsp;
224
225	return 0;
226
227free_rsp:
228	kfree(desc->rsp);
229unmap_req:
230	ib_dma_unmap_single(device->ib_device, desc->req_dma,
231			    ISCSI_DEF_MAX_RECV_SEG_LEN,
232			    DMA_TO_DEVICE);
233free_req:
234	kfree(desc->req);
235
236	return -ENOMEM;
237}
238
239int iser_alloc_rx_descriptors(struct iser_conn *iser_conn,
240			      struct iscsi_session *session)
241{
242	int i, j;
243	u64 dma_addr;
244	struct iser_rx_desc *rx_desc;
245	struct ib_sge       *rx_sg;
246	struct ib_conn *ib_conn = &iser_conn->ib_conn;
247	struct iser_device *device = ib_conn->device;
248
249	iser_conn->qp_max_recv_dtos = session->cmds_max;
250	iser_conn->qp_max_recv_dtos_mask = session->cmds_max - 1; /* cmds_max is 2^N */
251	iser_conn->min_posted_rx = iser_conn->qp_max_recv_dtos >> 2;
252
253	if (iser_alloc_fastreg_pool(ib_conn, session->scsi_cmds_max,
254				    iser_conn->pages_per_mr))
255		goto create_rdma_reg_res_failed;
256
257	if (iser_alloc_login_buf(iser_conn))
258		goto alloc_login_buf_fail;
259
260	iser_conn->num_rx_descs = session->cmds_max;
261	iser_conn->rx_descs = kmalloc_array(iser_conn->num_rx_descs,
262					    sizeof(struct iser_rx_desc),
263					    GFP_KERNEL);
264	if (!iser_conn->rx_descs)
265		goto rx_desc_alloc_fail;
266
267	rx_desc = iser_conn->rx_descs;
268
269	for (i = 0; i < iser_conn->qp_max_recv_dtos; i++, rx_desc++)  {
270		dma_addr = ib_dma_map_single(device->ib_device, (void *)rx_desc,
271					ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE);
272		if (ib_dma_mapping_error(device->ib_device, dma_addr))
273			goto rx_desc_dma_map_failed;
274
275		rx_desc->dma_addr = dma_addr;
276		rx_desc->cqe.done = iser_task_rsp;
277		rx_sg = &rx_desc->rx_sg;
278		rx_sg->addr = rx_desc->dma_addr;
279		rx_sg->length = ISER_RX_PAYLOAD_SIZE;
280		rx_sg->lkey = device->pd->local_dma_lkey;
281	}
282
283	iser_conn->rx_desc_head = 0;
284	return 0;
285
286rx_desc_dma_map_failed:
287	rx_desc = iser_conn->rx_descs;
288	for (j = 0; j < i; j++, rx_desc++)
289		ib_dma_unmap_single(device->ib_device, rx_desc->dma_addr,
290				    ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE);
291	kfree(iser_conn->rx_descs);
292	iser_conn->rx_descs = NULL;
293rx_desc_alloc_fail:
294	iser_free_login_buf(iser_conn);
295alloc_login_buf_fail:
296	iser_free_fastreg_pool(ib_conn);
297create_rdma_reg_res_failed:
298	iser_err("failed allocating rx descriptors / data buffers\n");
299	return -ENOMEM;
300}
301
302void iser_free_rx_descriptors(struct iser_conn *iser_conn)
303{
304	int i;
305	struct iser_rx_desc *rx_desc;
306	struct ib_conn *ib_conn = &iser_conn->ib_conn;
307	struct iser_device *device = ib_conn->device;
308
309	iser_free_fastreg_pool(ib_conn);
310
311	rx_desc = iser_conn->rx_descs;
312	for (i = 0; i < iser_conn->qp_max_recv_dtos; i++, rx_desc++)
313		ib_dma_unmap_single(device->ib_device, rx_desc->dma_addr,
314				    ISER_RX_PAYLOAD_SIZE, DMA_FROM_DEVICE);
315	kfree(iser_conn->rx_descs);
316	/* make sure we never redo any unmapping */
317	iser_conn->rx_descs = NULL;
318
319	iser_free_login_buf(iser_conn);
320}
321
322static int iser_post_rx_bufs(struct iscsi_conn *conn, struct iscsi_hdr *req)
323{
324	struct iser_conn *iser_conn = conn->dd_data;
325	struct ib_conn *ib_conn = &iser_conn->ib_conn;
326	struct iscsi_session *session = conn->session;
327
328	iser_dbg("req op %x flags %x\n", req->opcode, req->flags);
329	/* check if this is the last login - going to full feature phase */
330	if ((req->flags & ISCSI_FULL_FEATURE_PHASE) != ISCSI_FULL_FEATURE_PHASE)
331		return 0;
332
333	/*
334	 * Check that there is one posted recv buffer
335	 * (for the last login response).
336	 */
337	WARN_ON(ib_conn->post_recv_buf_count != 1);
338
339	if (session->discovery_sess) {
340		iser_info("Discovery session, re-using login RX buffer\n");
341		return 0;
342	} else
343		iser_info("Normal session, posting batch of RX %d buffers\n",
344			  iser_conn->min_posted_rx);
345
346	/* Initial post receive buffers */
347	if (iser_post_recvm(iser_conn, iser_conn->min_posted_rx))
348		return -ENOMEM;
349
350	return 0;
351}
352
353static inline bool iser_signal_comp(u8 sig_count)
354{
355	return ((sig_count % ISER_SIGNAL_CMD_COUNT) == 0);
356}
357
358/**
359 * iser_send_command - send command PDU
360 * @conn: link to matching iscsi connection
361 * @task: SCSI command task
362 */
363int iser_send_command(struct iscsi_conn *conn,
364		      struct iscsi_task *task)
365{
366	struct iser_conn *iser_conn = conn->dd_data;
367	struct iscsi_iser_task *iser_task = task->dd_data;
368	unsigned long edtl;
369	int err;
370	struct iser_data_buf *data_buf, *prot_buf;
371	struct iscsi_scsi_req *hdr = (struct iscsi_scsi_req *)task->hdr;
372	struct scsi_cmnd *sc  =  task->sc;
373	struct iser_tx_desc *tx_desc = &iser_task->desc;
374	u8 sig_count = ++iser_conn->ib_conn.sig_count;
375
376	edtl = ntohl(hdr->data_length);
377
378	/* build the tx desc regd header and add it to the tx desc dto */
379	tx_desc->type = ISCSI_TX_SCSI_COMMAND;
380	tx_desc->cqe.done = iser_cmd_comp;
381	iser_create_send_desc(iser_conn, tx_desc);
382
383	if (hdr->flags & ISCSI_FLAG_CMD_READ) {
384		data_buf = &iser_task->data[ISER_DIR_IN];
385		prot_buf = &iser_task->prot[ISER_DIR_IN];
386	} else {
387		data_buf = &iser_task->data[ISER_DIR_OUT];
388		prot_buf = &iser_task->prot[ISER_DIR_OUT];
389	}
390
391	if (scsi_sg_count(sc)) { /* using a scatter list */
392		data_buf->sg = scsi_sglist(sc);
393		data_buf->size = scsi_sg_count(sc);
394	}
395	data_buf->data_len = scsi_bufflen(sc);
396
397	if (scsi_prot_sg_count(sc)) {
398		prot_buf->sg  = scsi_prot_sglist(sc);
399		prot_buf->size = scsi_prot_sg_count(sc);
400		prot_buf->data_len = (data_buf->data_len >>
401				     ilog2(sc->device->sector_size)) * 8;
402	}
403
404	if (hdr->flags & ISCSI_FLAG_CMD_READ) {
405		err = iser_prepare_read_cmd(task);
406		if (err)
407			goto send_command_error;
408	}
409	if (hdr->flags & ISCSI_FLAG_CMD_WRITE) {
410		err = iser_prepare_write_cmd(task,
411					     task->imm_count,
412				             task->imm_count +
413					     task->unsol_r2t.data_length,
414					     edtl);
415		if (err)
416			goto send_command_error;
417	}
418
419	iser_task->status = ISER_TASK_STATUS_STARTED;
420
421	err = iser_post_send(&iser_conn->ib_conn, tx_desc,
422			     iser_signal_comp(sig_count));
423	if (!err)
424		return 0;
425
426send_command_error:
427	iser_err("conn %p failed task->itt %d err %d\n",conn, task->itt, err);
428	return err;
429}
430
431/**
432 * iser_send_data_out - send data out PDU
433 * @conn: link to matching iscsi connection
434 * @task: SCSI command task
435 * @hdr: pointer to the LLD's iSCSI message header
436 */
437int iser_send_data_out(struct iscsi_conn *conn,
438		       struct iscsi_task *task,
439		       struct iscsi_data *hdr)
440{
441	struct iser_conn *iser_conn = conn->dd_data;
442	struct iscsi_iser_task *iser_task = task->dd_data;
443	struct iser_tx_desc *tx_desc;
444	struct iser_mem_reg *mem_reg;
445	unsigned long buf_offset;
446	unsigned long data_seg_len;
447	uint32_t itt;
448	int err;
449	struct ib_sge *tx_dsg;
450
451	itt = (__force uint32_t)hdr->itt;
452	data_seg_len = ntoh24(hdr->dlength);
453	buf_offset   = ntohl(hdr->offset);
454
455	iser_dbg("%s itt %d dseg_len %d offset %d\n",
456		 __func__,(int)itt,(int)data_seg_len,(int)buf_offset);
457
458	tx_desc = kmem_cache_zalloc(ig.desc_cache, GFP_ATOMIC);
459	if (!tx_desc)
460		return -ENOMEM;
461
462	tx_desc->type = ISCSI_TX_DATAOUT;
463	tx_desc->cqe.done = iser_dataout_comp;
464	tx_desc->iser_header.flags = ISER_VER;
465	memcpy(&tx_desc->iscsi_header, hdr, sizeof(struct iscsi_hdr));
466
467	/* build the tx desc */
468	err = iser_initialize_task_headers(task, tx_desc);
469	if (err)
470		goto send_data_out_error;
471
472	mem_reg = &iser_task->rdma_reg[ISER_DIR_OUT];
473	tx_dsg = &tx_desc->tx_sg[1];
474	tx_dsg->addr = mem_reg->sge.addr + buf_offset;
475	tx_dsg->length = data_seg_len;
476	tx_dsg->lkey = mem_reg->sge.lkey;
477	tx_desc->num_sge = 2;
478
479	if (buf_offset + data_seg_len > iser_task->data[ISER_DIR_OUT].data_len) {
480		iser_err("Offset:%ld & DSL:%ld in Data-Out inconsistent with total len:%ld, itt:%d\n",
481			 buf_offset, data_seg_len,
482			 iser_task->data[ISER_DIR_OUT].data_len, itt);
483		err = -EINVAL;
484		goto send_data_out_error;
485	}
486	iser_dbg("data-out itt: %d, offset: %ld, sz: %ld\n",
487		 itt, buf_offset, data_seg_len);
488
489
490	err = iser_post_send(&iser_conn->ib_conn, tx_desc, true);
491	if (!err)
492		return 0;
493
494send_data_out_error:
495	kmem_cache_free(ig.desc_cache, tx_desc);
496	iser_err("conn %p failed err %d\n", conn, err);
497	return err;
498}
499
500int iser_send_control(struct iscsi_conn *conn,
501		      struct iscsi_task *task)
502{
503	struct iser_conn *iser_conn = conn->dd_data;
504	struct iscsi_iser_task *iser_task = task->dd_data;
505	struct iser_tx_desc *mdesc = &iser_task->desc;
506	unsigned long data_seg_len;
507	int err = 0;
508	struct iser_device *device;
509
510	/* build the tx desc regd header and add it to the tx desc dto */
511	mdesc->type = ISCSI_TX_CONTROL;
512	mdesc->cqe.done = iser_ctrl_comp;
513	iser_create_send_desc(iser_conn, mdesc);
514
515	device = iser_conn->ib_conn.device;
516
517	data_seg_len = ntoh24(task->hdr->dlength);
518
519	if (data_seg_len > 0) {
520		struct iser_login_desc *desc = &iser_conn->login_desc;
521		struct ib_sge *tx_dsg = &mdesc->tx_sg[1];
522
523		if (task != conn->login_task) {
524			iser_err("data present on non login task!!!\n");
525			goto send_control_error;
526		}
527
528		ib_dma_sync_single_for_cpu(device->ib_device, desc->req_dma,
529					   task->data_count, DMA_TO_DEVICE);
530
531		memcpy(desc->req, task->data, task->data_count);
532
533		ib_dma_sync_single_for_device(device->ib_device, desc->req_dma,
534					      task->data_count, DMA_TO_DEVICE);
535
536		tx_dsg->addr = desc->req_dma;
537		tx_dsg->length = task->data_count;
538		tx_dsg->lkey = device->pd->local_dma_lkey;
539		mdesc->num_sge = 2;
540	}
541
542	if (task == conn->login_task) {
543		iser_dbg("op %x dsl %lx, posting login rx buffer\n",
544			 task->hdr->opcode, data_seg_len);
545		err = iser_post_recvl(iser_conn);
546		if (err)
547			goto send_control_error;
548		err = iser_post_rx_bufs(conn, task->hdr);
549		if (err)
550			goto send_control_error;
551	}
552
553	err = iser_post_send(&iser_conn->ib_conn, mdesc, true);
554	if (!err)
555		return 0;
556
557send_control_error:
558	iser_err("conn %p failed err %d\n",conn, err);
559	return err;
560}
561
562void iser_login_rsp(struct ib_cq *cq, struct ib_wc *wc)
563{
564	struct ib_conn *ib_conn = wc->qp->qp_context;
565	struct iser_conn *iser_conn = to_iser_conn(ib_conn);
566	struct iser_login_desc *desc = iser_login(wc->wr_cqe);
567	struct iscsi_hdr *hdr;
568	char *data;
569	int length;
570
571	if (unlikely(wc->status != IB_WC_SUCCESS)) {
572		iser_err_comp(wc, "login_rsp");
573		return;
574	}
575
576	ib_dma_sync_single_for_cpu(ib_conn->device->ib_device,
577				   desc->rsp_dma, ISER_RX_LOGIN_SIZE,
578				   DMA_FROM_DEVICE);
579
580	hdr = desc->rsp + sizeof(struct iser_ctrl);
581	data = desc->rsp + ISER_HEADERS_LEN;
582	length = wc->byte_len - ISER_HEADERS_LEN;
583
584	iser_dbg("op 0x%x itt 0x%x dlen %d\n", hdr->opcode,
585		 hdr->itt, length);
586
587	iscsi_iser_recv(iser_conn->iscsi_conn, hdr, data, length);
588
589	ib_dma_sync_single_for_device(ib_conn->device->ib_device,
590				      desc->rsp_dma, ISER_RX_LOGIN_SIZE,
591				      DMA_FROM_DEVICE);
592
593	ib_conn->post_recv_buf_count--;
594}
595
596static inline int
597iser_inv_desc(struct iser_fr_desc *desc, u32 rkey)
598{
599	if (unlikely((!desc->sig_protected && rkey != desc->rsc.mr->rkey) ||
600		     (desc->sig_protected && rkey != desc->rsc.sig_mr->rkey))) {
601		iser_err("Bogus remote invalidation for rkey %#x\n", rkey);
602		return -EINVAL;
603	}
604
605	if (desc->sig_protected)
606		desc->rsc.sig_mr->need_inval = false;
607	else
608		desc->rsc.mr->need_inval = false;
609
610	return 0;
611}
612
613static int
614iser_check_remote_inv(struct iser_conn *iser_conn,
615		      struct ib_wc *wc,
616		      struct iscsi_hdr *hdr)
617{
618	if (wc->wc_flags & IB_WC_WITH_INVALIDATE) {
619		struct iscsi_task *task;
620		u32 rkey = wc->ex.invalidate_rkey;
621
622		iser_dbg("conn %p: remote invalidation for rkey %#x\n",
623			 iser_conn, rkey);
624
625		if (unlikely(!iser_conn->snd_w_inv)) {
626			iser_err("conn %p: unexpected remote invalidation, terminating connection\n",
627				 iser_conn);
628			return -EPROTO;
629		}
630
631		task = iscsi_itt_to_ctask(iser_conn->iscsi_conn, hdr->itt);
632		if (likely(task)) {
633			struct iscsi_iser_task *iser_task = task->dd_data;
634			struct iser_fr_desc *desc;
635
636			if (iser_task->dir[ISER_DIR_IN]) {
637				desc = iser_task->rdma_reg[ISER_DIR_IN].mem_h;
638				if (unlikely(iser_inv_desc(desc, rkey)))
639					return -EINVAL;
640			}
641
642			if (iser_task->dir[ISER_DIR_OUT]) {
643				desc = iser_task->rdma_reg[ISER_DIR_OUT].mem_h;
644				if (unlikely(iser_inv_desc(desc, rkey)))
645					return -EINVAL;
646			}
647		} else {
648			iser_err("failed to get task for itt=%d\n", hdr->itt);
649			return -EINVAL;
650		}
651	}
652
653	return 0;
654}
655
656
657void iser_task_rsp(struct ib_cq *cq, struct ib_wc *wc)
658{
659	struct ib_conn *ib_conn = wc->qp->qp_context;
660	struct iser_conn *iser_conn = to_iser_conn(ib_conn);
661	struct iser_rx_desc *desc = iser_rx(wc->wr_cqe);
662	struct iscsi_hdr *hdr;
663	int length;
664	int outstanding, count, err;
665
666	if (unlikely(wc->status != IB_WC_SUCCESS)) {
667		iser_err_comp(wc, "task_rsp");
668		return;
669	}
670
671	ib_dma_sync_single_for_cpu(ib_conn->device->ib_device,
672				   desc->dma_addr, ISER_RX_PAYLOAD_SIZE,
673				   DMA_FROM_DEVICE);
674
675	hdr = &desc->iscsi_header;
676	length = wc->byte_len - ISER_HEADERS_LEN;
677
678	iser_dbg("op 0x%x itt 0x%x dlen %d\n", hdr->opcode,
679		 hdr->itt, length);
680
681	if (iser_check_remote_inv(iser_conn, wc, hdr)) {
682		iscsi_conn_failure(iser_conn->iscsi_conn,
683				   ISCSI_ERR_CONN_FAILED);
684		return;
685	}
686
687	iscsi_iser_recv(iser_conn->iscsi_conn, hdr, desc->data, length);
688
689	ib_dma_sync_single_for_device(ib_conn->device->ib_device,
690				      desc->dma_addr, ISER_RX_PAYLOAD_SIZE,
691				      DMA_FROM_DEVICE);
692
693	/* decrementing conn->post_recv_buf_count only --after-- freeing the   *
694	 * task eliminates the need to worry on tasks which are completed in   *
695	 * parallel to the execution of iser_conn_term. So the code that waits *
696	 * for the posted rx bufs refcount to become zero handles everything   */
697	ib_conn->post_recv_buf_count--;
698
699	outstanding = ib_conn->post_recv_buf_count;
700	if (outstanding + iser_conn->min_posted_rx <= iser_conn->qp_max_recv_dtos) {
701		count = min(iser_conn->qp_max_recv_dtos - outstanding,
702			    iser_conn->min_posted_rx);
703		err = iser_post_recvm(iser_conn, count);
704		if (err)
705			iser_err("posting %d rx bufs err %d\n", count, err);
706	}
707}
708
709void iser_cmd_comp(struct ib_cq *cq, struct ib_wc *wc)
710{
711	if (unlikely(wc->status != IB_WC_SUCCESS))
712		iser_err_comp(wc, "command");
713}
714
715void iser_ctrl_comp(struct ib_cq *cq, struct ib_wc *wc)
716{
717	struct iser_tx_desc *desc = iser_tx(wc->wr_cqe);
718	struct iscsi_task *task;
719
720	if (unlikely(wc->status != IB_WC_SUCCESS)) {
721		iser_err_comp(wc, "control");
722		return;
723	}
724
725	/* this arithmetic is legal by libiscsi dd_data allocation */
726	task = (void *)desc - sizeof(struct iscsi_task);
727	if (task->hdr->itt == RESERVED_ITT)
728		iscsi_put_task(task);
729}
730
731void iser_dataout_comp(struct ib_cq *cq, struct ib_wc *wc)
732{
733	struct iser_tx_desc *desc = iser_tx(wc->wr_cqe);
734	struct ib_conn *ib_conn = wc->qp->qp_context;
735	struct iser_device *device = ib_conn->device;
736
737	if (unlikely(wc->status != IB_WC_SUCCESS))
738		iser_err_comp(wc, "dataout");
739
740	ib_dma_unmap_single(device->ib_device, desc->dma_addr,
741			    ISER_HEADERS_LEN, DMA_TO_DEVICE);
742	kmem_cache_free(ig.desc_cache, desc);
743}
744
745void iser_task_rdma_init(struct iscsi_iser_task *iser_task)
746
747{
748	iser_task->status = ISER_TASK_STATUS_INIT;
749
750	iser_task->dir[ISER_DIR_IN] = 0;
751	iser_task->dir[ISER_DIR_OUT] = 0;
752
753	iser_task->data[ISER_DIR_IN].data_len  = 0;
754	iser_task->data[ISER_DIR_OUT].data_len = 0;
755
756	iser_task->prot[ISER_DIR_IN].data_len  = 0;
757	iser_task->prot[ISER_DIR_OUT].data_len = 0;
758
759	iser_task->prot[ISER_DIR_IN].dma_nents = 0;
760	iser_task->prot[ISER_DIR_OUT].dma_nents = 0;
761
762	memset(&iser_task->rdma_reg[ISER_DIR_IN], 0,
763	       sizeof(struct iser_mem_reg));
764	memset(&iser_task->rdma_reg[ISER_DIR_OUT], 0,
765	       sizeof(struct iser_mem_reg));
766}
767
768void iser_task_rdma_finalize(struct iscsi_iser_task *iser_task)
769{
770	int prot_count = scsi_prot_sg_count(iser_task->sc);
771
772	if (iser_task->dir[ISER_DIR_IN]) {
773		iser_unreg_mem_fastreg(iser_task, ISER_DIR_IN);
774		iser_dma_unmap_task_data(iser_task,
775					 &iser_task->data[ISER_DIR_IN],
776					 DMA_FROM_DEVICE);
777		if (prot_count)
778			iser_dma_unmap_task_data(iser_task,
779						 &iser_task->prot[ISER_DIR_IN],
780						 DMA_FROM_DEVICE);
781	}
782
783	if (iser_task->dir[ISER_DIR_OUT]) {
784		iser_unreg_mem_fastreg(iser_task, ISER_DIR_OUT);
785		iser_dma_unmap_task_data(iser_task,
786					 &iser_task->data[ISER_DIR_OUT],
787					 DMA_TO_DEVICE);
788		if (prot_count)
789			iser_dma_unmap_task_data(iser_task,
790						 &iser_task->prot[ISER_DIR_OUT],
791						 DMA_TO_DEVICE);
792	}
793}
794