1 /*
2 * iSCSI Initiator over iSER Data-Path
3 *
4 * Copyright (C) 2004 Dmitry Yusupov
5 * Copyright (C) 2004 Alex Aizman
6 * Copyright (C) 2005 Mike Christie
7 * Copyright (c) 2005, 2006 Voltaire, Inc. All rights reserved.
8 * Copyright (c) 2013-2014 Mellanox Technologies. All rights reserved.
9 * maintained by openib-general@openib.org
10 *
11 * This software is available to you under a choice of one of two
12 * licenses. You may choose to be licensed under the terms of the GNU
13 * General Public License (GPL) Version 2, available from the file
14 * COPYING in the main directory of this source tree, or the
15 * OpenIB.org BSD license below:
16 *
17 * Redistribution and use in source and binary forms, with or
18 * without modification, are permitted provided that the following
19 * conditions are met:
20 *
21 * - Redistributions of source code must retain the above
22 * copyright notice, this list of conditions and the following
23 * disclaimer.
24 *
25 * - Redistributions in binary form must reproduce the above
26 * copyright notice, this list of conditions and the following
27 * disclaimer in the documentation and/or other materials
28 * provided with the distribution.
29 *
30 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
31 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
32 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
33 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
34 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
35 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
36 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
37 * SOFTWARE.
38 *
39 * Credits:
40 * Christoph Hellwig
41 * FUJITA Tomonori
42 * Arne Redlich
43 * Zhenyu Wang
44 * Modified by:
45 * Erez Zilber
46 */
47
48 #include <linux/types.h>
49 #include <linux/list.h>
50 #include <linux/hardirq.h>
51 #include <linux/kfifo.h>
52 #include <linux/blkdev.h>
53 #include <linux/init.h>
54 #include <linux/ioctl.h>
55 #include <linux/cdev.h>
56 #include <linux/in.h>
57 #include <linux/net.h>
58 #include <linux/scatterlist.h>
59 #include <linux/delay.h>
60 #include <linux/slab.h>
61 #include <linux/module.h>
62
63 #include <net/sock.h>
64
65 #include <linux/uaccess.h>
66
67 #include <scsi/scsi_cmnd.h>
68 #include <scsi/scsi_device.h>
69 #include <scsi/scsi_eh.h>
70 #include <scsi/scsi_tcq.h>
71 #include <scsi/scsi_host.h>
72 #include <scsi/scsi.h>
73 #include <scsi/scsi_transport_iscsi.h>
74
75 #include "iscsi_iser.h"
76
77 MODULE_DESCRIPTION("iSER (iSCSI Extensions for RDMA) Datamover");
78 MODULE_LICENSE("Dual BSD/GPL");
79 MODULE_AUTHOR("Alex Nezhinsky, Dan Bar Dov, Or Gerlitz");
80
81 static const struct scsi_host_template iscsi_iser_sht;
82 static struct iscsi_transport iscsi_iser_transport;
83 static struct scsi_transport_template *iscsi_iser_scsi_transport;
84 static struct workqueue_struct *release_wq;
85 static DEFINE_MUTEX(unbind_iser_conn_mutex);
86 struct iser_global ig;
87
88 int iser_debug_level = 0;
89 module_param_named(debug_level, iser_debug_level, int, S_IRUGO | S_IWUSR);
90 MODULE_PARM_DESC(debug_level, "Enable debug tracing if > 0 (default:disabled)");
91
92 static int iscsi_iser_set(const char *val, const struct kernel_param *kp);
93 static const struct kernel_param_ops iscsi_iser_size_ops = {
94 .set = iscsi_iser_set,
95 .get = param_get_uint,
96 };
97
98 static unsigned int iscsi_max_lun = 512;
99 module_param_cb(max_lun, &iscsi_iser_size_ops, &iscsi_max_lun, S_IRUGO);
100 MODULE_PARM_DESC(max_lun, "Max LUNs to allow per session, should > 0 (default:512)");
101
102 unsigned int iser_max_sectors = ISER_DEF_MAX_SECTORS;
103 module_param_cb(max_sectors, &iscsi_iser_size_ops, &iser_max_sectors,
104 S_IRUGO | S_IWUSR);
105 MODULE_PARM_DESC(max_sectors, "Max number of sectors in a single scsi command, should > 0 (default:1024)");
106
107 bool iser_always_reg = true;
108 module_param_named(always_register, iser_always_reg, bool, S_IRUGO);
109 MODULE_PARM_DESC(always_register,
110 "Always register memory, even for continuous memory regions (default:true)");
111
112 bool iser_pi_enable = false;
113 module_param_named(pi_enable, iser_pi_enable, bool, S_IRUGO);
114 MODULE_PARM_DESC(pi_enable, "Enable T10-PI offload support (default:disabled)");
115
iscsi_iser_set(const char * val,const struct kernel_param * kp)116 static int iscsi_iser_set(const char *val, const struct kernel_param *kp)
117 {
118 int ret;
119 unsigned int n = 0;
120
121 ret = kstrtouint(val, 10, &n);
122 if (ret != 0 || n == 0)
123 return -EINVAL;
124
125 return param_set_uint(val, kp);
126 }
127
128 /*
129 * iscsi_iser_recv() - Process a successful recv completion
130 * @conn: iscsi connection
131 * @hdr: iscsi header
132 * @rx_data: buffer containing receive data payload
133 * @rx_data_len: length of rx_data
134 *
135 * Notes: In case of data length errors or iscsi PDU completion failures
136 * this routine will signal iscsi layer of connection failure.
137 */
iscsi_iser_recv(struct iscsi_conn * conn,struct iscsi_hdr * hdr,char * rx_data,int rx_data_len)138 void iscsi_iser_recv(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
139 char *rx_data, int rx_data_len)
140 {
141 int rc = 0;
142 int datalen;
143
144 /* verify PDU length */
145 datalen = ntoh24(hdr->dlength);
146 if (datalen > rx_data_len || (datalen + 4) < rx_data_len) {
147 iser_err("wrong datalen %d (hdr), %d (IB)\n",
148 datalen, rx_data_len);
149 rc = ISCSI_ERR_DATALEN;
150 goto error;
151 }
152
153 if (datalen != rx_data_len)
154 iser_dbg("aligned datalen (%d) hdr, %d (IB)\n",
155 datalen, rx_data_len);
156
157 rc = iscsi_complete_pdu(conn, hdr, rx_data, rx_data_len);
158 if (rc && rc != ISCSI_ERR_NO_SCSI_CMD)
159 goto error;
160
161 return;
162 error:
163 iscsi_conn_failure(conn, rc);
164 }
165
166 /**
167 * iscsi_iser_pdu_alloc() - allocate an iscsi-iser PDU
168 * @task: iscsi task
169 * @opcode: iscsi command opcode
170 *
171 * Netes: This routine can't fail, just assign iscsi task
172 * hdr and max hdr size.
173 */
iscsi_iser_pdu_alloc(struct iscsi_task * task,uint8_t opcode)174 static int iscsi_iser_pdu_alloc(struct iscsi_task *task, uint8_t opcode)
175 {
176 struct iscsi_iser_task *iser_task = task->dd_data;
177
178 task->hdr = (struct iscsi_hdr *)&iser_task->desc.iscsi_header;
179 task->hdr_max = sizeof(iser_task->desc.iscsi_header);
180
181 return 0;
182 }
183
184 /**
185 * iser_initialize_task_headers() - Initialize task headers
186 * @task: iscsi task
187 * @tx_desc: iser tx descriptor
188 *
189 * Notes:
190 * This routine may race with iser teardown flow for scsi
191 * error handling TMFs. So for TMF we should acquire the
192 * state mutex to avoid dereferencing the IB device which
193 * may have already been terminated.
194 */
iser_initialize_task_headers(struct iscsi_task * task,struct iser_tx_desc * tx_desc)195 int iser_initialize_task_headers(struct iscsi_task *task,
196 struct iser_tx_desc *tx_desc)
197 {
198 struct iser_conn *iser_conn = task->conn->dd_data;
199 struct iser_device *device = iser_conn->ib_conn.device;
200 struct iscsi_iser_task *iser_task = task->dd_data;
201 u64 dma_addr;
202
203 if (unlikely(iser_conn->state != ISER_CONN_UP))
204 return -ENODEV;
205
206 dma_addr = ib_dma_map_single(device->ib_device, (void *)tx_desc,
207 ISER_HEADERS_LEN, DMA_TO_DEVICE);
208 if (ib_dma_mapping_error(device->ib_device, dma_addr))
209 return -ENOMEM;
210
211 tx_desc->inv_wr.next = NULL;
212 tx_desc->reg_wr.wr.next = NULL;
213 tx_desc->mapped = true;
214 tx_desc->dma_addr = dma_addr;
215 tx_desc->tx_sg[0].addr = tx_desc->dma_addr;
216 tx_desc->tx_sg[0].length = ISER_HEADERS_LEN;
217 tx_desc->tx_sg[0].lkey = device->pd->local_dma_lkey;
218
219 iser_task->iser_conn = iser_conn;
220
221 return 0;
222 }
223
224 /**
225 * iscsi_iser_task_init() - Initialize iscsi-iser task
226 * @task: iscsi task
227 *
228 * Initialize the task for the scsi command or mgmt command.
229 *
230 * Return: Returns zero on success or -ENOMEM when failing
231 * to init task headers (dma mapping error).
232 */
iscsi_iser_task_init(struct iscsi_task * task)233 static int iscsi_iser_task_init(struct iscsi_task *task)
234 {
235 struct iscsi_iser_task *iser_task = task->dd_data;
236 int ret;
237
238 ret = iser_initialize_task_headers(task, &iser_task->desc);
239 if (ret) {
240 iser_err("Failed to init task %p, err = %d\n",
241 iser_task, ret);
242 return ret;
243 }
244
245 /* mgmt task */
246 if (!task->sc)
247 return 0;
248
249 iser_task->command_sent = 0;
250 iser_task_rdma_init(iser_task);
251 iser_task->sc = task->sc;
252
253 return 0;
254 }
255
256 /**
257 * iscsi_iser_mtask_xmit() - xmit management (immediate) task
258 * @conn: iscsi connection
259 * @task: task management task
260 *
261 * Notes:
262 * The function can return -EAGAIN in which case caller must
263 * call it again later, or recover. '0' return code means successful
264 * xmit.
265 *
266 **/
iscsi_iser_mtask_xmit(struct iscsi_conn * conn,struct iscsi_task * task)267 static int iscsi_iser_mtask_xmit(struct iscsi_conn *conn,
268 struct iscsi_task *task)
269 {
270 iser_dbg("mtask xmit [cid %d itt 0x%x]\n", conn->id, task->itt);
271
272 /* since iser xmits control with zero copy, tasks can not be recycled
273 * right after sending them.
274 * The recycling scheme is based on whether a response is expected
275 * - if yes, the task is recycled at iscsi_complete_pdu
276 * - if no, the task is recycled at iser_snd_completion
277 */
278 return iser_send_control(conn, task);
279 }
280
iscsi_iser_task_xmit_unsol_data(struct iscsi_conn * conn,struct iscsi_task * task)281 static int iscsi_iser_task_xmit_unsol_data(struct iscsi_conn *conn,
282 struct iscsi_task *task)
283 {
284 struct iscsi_r2t_info *r2t = &task->unsol_r2t;
285 struct iscsi_data hdr;
286 int error = 0;
287
288 /* Send data-out PDUs while there's still unsolicited data to send */
289 while (iscsi_task_has_unsol_data(task)) {
290 iscsi_prep_data_out_pdu(task, r2t, &hdr);
291 iser_dbg("Sending data-out: itt 0x%x, data count %d\n",
292 hdr.itt, r2t->data_count);
293
294 /* the buffer description has been passed with the command */
295 /* Send the command */
296 error = iser_send_data_out(conn, task, &hdr);
297 if (error) {
298 r2t->datasn--;
299 goto iscsi_iser_task_xmit_unsol_data_exit;
300 }
301 r2t->sent += r2t->data_count;
302 iser_dbg("Need to send %d more as data-out PDUs\n",
303 r2t->data_length - r2t->sent);
304 }
305
306 iscsi_iser_task_xmit_unsol_data_exit:
307 return error;
308 }
309
310 /**
311 * iscsi_iser_task_xmit() - xmit iscsi-iser task
312 * @task: iscsi task
313 *
314 * Return: zero on success or escalates $error on failure.
315 */
iscsi_iser_task_xmit(struct iscsi_task * task)316 static int iscsi_iser_task_xmit(struct iscsi_task *task)
317 {
318 struct iscsi_conn *conn = task->conn;
319 struct iscsi_iser_task *iser_task = task->dd_data;
320 int error = 0;
321
322 if (!task->sc)
323 return iscsi_iser_mtask_xmit(conn, task);
324
325 if (task->sc->sc_data_direction == DMA_TO_DEVICE) {
326 BUG_ON(scsi_bufflen(task->sc) == 0);
327
328 iser_dbg("cmd [itt %x total %d imm %d unsol_data %d\n",
329 task->itt, scsi_bufflen(task->sc),
330 task->imm_count, task->unsol_r2t.data_length);
331 }
332
333 iser_dbg("ctask xmit [cid %d itt 0x%x]\n",
334 conn->id, task->itt);
335
336 /* Send the cmd PDU */
337 if (!iser_task->command_sent) {
338 error = iser_send_command(conn, task);
339 if (error)
340 goto iscsi_iser_task_xmit_exit;
341 iser_task->command_sent = 1;
342 }
343
344 /* Send unsolicited data-out PDU(s) if necessary */
345 if (iscsi_task_has_unsol_data(task))
346 error = iscsi_iser_task_xmit_unsol_data(conn, task);
347
348 iscsi_iser_task_xmit_exit:
349 return error;
350 }
351
352 /**
353 * iscsi_iser_cleanup_task() - cleanup an iscsi-iser task
354 * @task: iscsi task
355 *
356 * Notes: In case the RDMA device is already NULL (might have
357 * been removed in DEVICE_REMOVAL CM event it will bail-out
358 * without doing dma unmapping.
359 */
iscsi_iser_cleanup_task(struct iscsi_task * task)360 static void iscsi_iser_cleanup_task(struct iscsi_task *task)
361 {
362 struct iscsi_iser_task *iser_task = task->dd_data;
363 struct iser_tx_desc *tx_desc = &iser_task->desc;
364 struct iser_conn *iser_conn = task->conn->dd_data;
365 struct iser_device *device = iser_conn->ib_conn.device;
366
367 /* DEVICE_REMOVAL event might have already released the device */
368 if (!device)
369 return;
370
371 if (likely(tx_desc->mapped)) {
372 ib_dma_unmap_single(device->ib_device, tx_desc->dma_addr,
373 ISER_HEADERS_LEN, DMA_TO_DEVICE);
374 tx_desc->mapped = false;
375 }
376
377 /* mgmt tasks do not need special cleanup */
378 if (!task->sc)
379 return;
380
381 if (iser_task->status == ISER_TASK_STATUS_STARTED) {
382 iser_task->status = ISER_TASK_STATUS_COMPLETED;
383 iser_task_rdma_finalize(iser_task);
384 }
385 }
386
387 /**
388 * iscsi_iser_check_protection() - check protection information status of task.
389 * @task: iscsi task
390 * @sector: error sector if exsists (output)
391 *
392 * Return: zero if no data-integrity errors have occurred
393 * 0x1: data-integrity error occurred in the guard-block
394 * 0x2: data-integrity error occurred in the reference tag
395 * 0x3: data-integrity error occurred in the application tag
396 *
397 * In addition the error sector is marked.
398 */
iscsi_iser_check_protection(struct iscsi_task * task,sector_t * sector)399 static u8 iscsi_iser_check_protection(struct iscsi_task *task, sector_t *sector)
400 {
401 struct iscsi_iser_task *iser_task = task->dd_data;
402 enum iser_data_dir dir = iser_task->dir[ISER_DIR_IN] ?
403 ISER_DIR_IN : ISER_DIR_OUT;
404
405 return iser_check_task_pi_status(iser_task, dir, sector);
406 }
407
408 /**
409 * iscsi_iser_conn_create() - create a new iscsi-iser connection
410 * @cls_session: iscsi class connection
411 * @conn_idx: connection index within the session (for MCS)
412 *
413 * Return: iscsi_cls_conn when iscsi_conn_setup succeeds or NULL
414 * otherwise.
415 */
416 static struct iscsi_cls_conn *
iscsi_iser_conn_create(struct iscsi_cls_session * cls_session,uint32_t conn_idx)417 iscsi_iser_conn_create(struct iscsi_cls_session *cls_session,
418 uint32_t conn_idx)
419 {
420 struct iscsi_conn *conn;
421 struct iscsi_cls_conn *cls_conn;
422
423 cls_conn = iscsi_conn_setup(cls_session, 0, conn_idx);
424 if (!cls_conn)
425 return NULL;
426 conn = cls_conn->dd_data;
427
428 /*
429 * due to issues with the login code re iser sematics
430 * this not set in iscsi_conn_setup - FIXME
431 */
432 conn->max_recv_dlength = ISER_RECV_DATA_SEG_LEN;
433
434 return cls_conn;
435 }
436
437 /**
438 * iscsi_iser_conn_bind() - bind iscsi and iser connection structures
439 * @cls_session: iscsi class session
440 * @cls_conn: iscsi class connection
441 * @transport_eph: transport end-point handle
442 * @is_leading: indicate if this is the session leading connection (MCS)
443 *
444 * Return: zero on success, $error if iscsi_conn_bind fails and
445 * -EINVAL in case end-point doesn't exists anymore or iser connection
446 * state is not UP (teardown already started).
447 */
iscsi_iser_conn_bind(struct iscsi_cls_session * cls_session,struct iscsi_cls_conn * cls_conn,uint64_t transport_eph,int is_leading)448 static int iscsi_iser_conn_bind(struct iscsi_cls_session *cls_session,
449 struct iscsi_cls_conn *cls_conn,
450 uint64_t transport_eph, int is_leading)
451 {
452 struct iscsi_conn *conn = cls_conn->dd_data;
453 struct iser_conn *iser_conn;
454 struct iscsi_endpoint *ep;
455 int error;
456
457 error = iscsi_conn_bind(cls_session, cls_conn, is_leading);
458 if (error)
459 return error;
460
461 /* the transport ep handle comes from user space so it must be
462 * verified against the global ib connections list */
463 ep = iscsi_lookup_endpoint(transport_eph);
464 if (!ep) {
465 iser_err("can't bind eph %llx\n",
466 (unsigned long long)transport_eph);
467 return -EINVAL;
468 }
469 iser_conn = ep->dd_data;
470
471 mutex_lock(&iser_conn->state_mutex);
472 if (iser_conn->state != ISER_CONN_UP) {
473 error = -EINVAL;
474 iser_err("iser_conn %p state is %d, teardown started\n",
475 iser_conn, iser_conn->state);
476 goto out;
477 }
478
479 error = iser_alloc_rx_descriptors(iser_conn, conn->session);
480 if (error)
481 goto out;
482
483 /* binds the iSER connection retrieved from the previously
484 * connected ep_handle to the iSCSI layer connection. exchanges
485 * connection pointers */
486 iser_info("binding iscsi conn %p to iser_conn %p\n", conn, iser_conn);
487
488 conn->dd_data = iser_conn;
489 iser_conn->iscsi_conn = conn;
490
491 out:
492 iscsi_put_endpoint(ep);
493 mutex_unlock(&iser_conn->state_mutex);
494 return error;
495 }
496
497 /**
498 * iscsi_iser_conn_start() - start iscsi-iser connection
499 * @cls_conn: iscsi class connection
500 *
501 * Notes: Here iser intialize (or re-initialize) stop_completion as
502 * from this point iscsi must call conn_stop in session/connection
503 * teardown so iser transport must wait for it.
504 */
iscsi_iser_conn_start(struct iscsi_cls_conn * cls_conn)505 static int iscsi_iser_conn_start(struct iscsi_cls_conn *cls_conn)
506 {
507 struct iscsi_conn *iscsi_conn;
508 struct iser_conn *iser_conn;
509
510 iscsi_conn = cls_conn->dd_data;
511 iser_conn = iscsi_conn->dd_data;
512 reinit_completion(&iser_conn->stop_completion);
513
514 return iscsi_conn_start(cls_conn);
515 }
516
517 /**
518 * iscsi_iser_conn_stop() - stop iscsi-iser connection
519 * @cls_conn: iscsi class connection
520 * @flag: indicate if recover or terminate (passed as is)
521 *
522 * Notes: Calling iscsi_conn_stop might theoretically race with
523 * DEVICE_REMOVAL event and dereference a previously freed RDMA device
524 * handle, so we call it under iser the state lock to protect against
525 * this kind of race.
526 */
iscsi_iser_conn_stop(struct iscsi_cls_conn * cls_conn,int flag)527 static void iscsi_iser_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
528 {
529 struct iscsi_conn *conn = cls_conn->dd_data;
530 struct iser_conn *iser_conn = conn->dd_data;
531
532 iser_info("stopping iscsi_conn: %p, iser_conn: %p\n", conn, iser_conn);
533
534 /*
535 * Userspace may have goofed up and not bound the connection or
536 * might have only partially setup the connection.
537 */
538 if (iser_conn) {
539 mutex_lock(&iser_conn->state_mutex);
540 mutex_lock(&unbind_iser_conn_mutex);
541 iser_conn_terminate(iser_conn);
542 iscsi_conn_stop(cls_conn, flag);
543
544 /* unbind */
545 iser_conn->iscsi_conn = NULL;
546 conn->dd_data = NULL;
547 mutex_unlock(&unbind_iser_conn_mutex);
548
549 complete(&iser_conn->stop_completion);
550 mutex_unlock(&iser_conn->state_mutex);
551 } else {
552 iscsi_conn_stop(cls_conn, flag);
553 }
554 }
555
556 /**
557 * iscsi_iser_session_destroy() - destroy iscsi-iser session
558 * @cls_session: iscsi class session
559 *
560 * Removes and free iscsi host.
561 */
iscsi_iser_session_destroy(struct iscsi_cls_session * cls_session)562 static void iscsi_iser_session_destroy(struct iscsi_cls_session *cls_session)
563 {
564 struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
565
566 iscsi_session_teardown(cls_session);
567 iscsi_host_remove(shost, false);
568 iscsi_host_free(shost);
569 }
570
iser_dif_prot_caps(int prot_caps)571 static inline unsigned int iser_dif_prot_caps(int prot_caps)
572 {
573 int ret = 0;
574
575 if (prot_caps & IB_PROT_T10DIF_TYPE_1)
576 ret |= SHOST_DIF_TYPE1_PROTECTION |
577 SHOST_DIX_TYPE0_PROTECTION |
578 SHOST_DIX_TYPE1_PROTECTION;
579 if (prot_caps & IB_PROT_T10DIF_TYPE_2)
580 ret |= SHOST_DIF_TYPE2_PROTECTION |
581 SHOST_DIX_TYPE2_PROTECTION;
582 if (prot_caps & IB_PROT_T10DIF_TYPE_3)
583 ret |= SHOST_DIF_TYPE3_PROTECTION |
584 SHOST_DIX_TYPE3_PROTECTION;
585
586 return ret;
587 }
588
589 /**
590 * iscsi_iser_session_create() - create an iscsi-iser session
591 * @ep: iscsi end-point handle
592 * @cmds_max: maximum commands in this session
593 * @qdepth: session command queue depth
594 * @initial_cmdsn: initiator command sequnce number
595 *
596 * Allocates and adds a scsi host, expose DIF supprot if
597 * exists, and sets up an iscsi session.
598 */
599 static struct iscsi_cls_session *
iscsi_iser_session_create(struct iscsi_endpoint * ep,uint16_t cmds_max,uint16_t qdepth,uint32_t initial_cmdsn)600 iscsi_iser_session_create(struct iscsi_endpoint *ep,
601 uint16_t cmds_max, uint16_t qdepth,
602 uint32_t initial_cmdsn)
603 {
604 struct iscsi_cls_session *cls_session;
605 struct Scsi_Host *shost;
606 struct iser_conn *iser_conn = NULL;
607 struct ib_conn *ib_conn;
608 struct ib_device *ib_dev;
609 u32 max_fr_sectors;
610
611 shost = iscsi_host_alloc(&iscsi_iser_sht, 0, 0);
612 if (!shost)
613 return NULL;
614 shost->transportt = iscsi_iser_scsi_transport;
615 shost->cmd_per_lun = qdepth;
616 shost->max_lun = iscsi_max_lun;
617 shost->max_id = 0;
618 shost->max_channel = 0;
619 shost->max_cmd_len = 16;
620
621 /*
622 * older userspace tools (before 2.0-870) did not pass us
623 * the leading conn's ep so this will be NULL;
624 */
625 if (ep) {
626 iser_conn = ep->dd_data;
627 shost->sg_tablesize = iser_conn->scsi_sg_tablesize;
628 shost->can_queue = min_t(u16, cmds_max, iser_conn->max_cmds);
629
630 mutex_lock(&iser_conn->state_mutex);
631 if (iser_conn->state != ISER_CONN_UP) {
632 iser_err("iser conn %p already started teardown\n",
633 iser_conn);
634 mutex_unlock(&iser_conn->state_mutex);
635 goto free_host;
636 }
637
638 ib_conn = &iser_conn->ib_conn;
639 ib_dev = ib_conn->device->ib_device;
640 if (ib_conn->pi_support) {
641 u32 sig_caps = ib_dev->attrs.sig_prot_cap;
642
643 shost->sg_prot_tablesize = shost->sg_tablesize;
644 scsi_host_set_prot(shost, iser_dif_prot_caps(sig_caps));
645 scsi_host_set_guard(shost, SHOST_DIX_GUARD_IP |
646 SHOST_DIX_GUARD_CRC);
647 }
648
649 if (!(ib_dev->attrs.kernel_cap_flags & IBK_SG_GAPS_REG))
650 shost->virt_boundary_mask = SZ_4K - 1;
651
652 if (iscsi_host_add(shost, ib_dev->dev.parent)) {
653 mutex_unlock(&iser_conn->state_mutex);
654 goto free_host;
655 }
656 mutex_unlock(&iser_conn->state_mutex);
657 } else {
658 shost->can_queue = min_t(u16, cmds_max, ISER_DEF_XMIT_CMDS_MAX);
659 if (iscsi_host_add(shost, NULL))
660 goto free_host;
661 }
662
663 max_fr_sectors = (shost->sg_tablesize * PAGE_SIZE) >> 9;
664 shost->max_sectors = min(iser_max_sectors, max_fr_sectors);
665
666 iser_dbg("iser_conn %p, sg_tablesize %u, max_sectors %u\n",
667 iser_conn, shost->sg_tablesize,
668 shost->max_sectors);
669
670 if (shost->max_sectors < iser_max_sectors)
671 iser_warn("max_sectors was reduced from %u to %u\n",
672 iser_max_sectors, shost->max_sectors);
673
674 cls_session = iscsi_session_setup(&iscsi_iser_transport, shost,
675 shost->can_queue, 0,
676 sizeof(struct iscsi_iser_task),
677 initial_cmdsn, 0);
678 if (!cls_session)
679 goto remove_host;
680
681 return cls_session;
682
683 remove_host:
684 iscsi_host_remove(shost, false);
685 free_host:
686 iscsi_host_free(shost);
687 return NULL;
688 }
689
iscsi_iser_set_param(struct iscsi_cls_conn * cls_conn,enum iscsi_param param,char * buf,int buflen)690 static int iscsi_iser_set_param(struct iscsi_cls_conn *cls_conn,
691 enum iscsi_param param, char *buf, int buflen)
692 {
693 int value;
694
695 switch (param) {
696 case ISCSI_PARAM_MAX_RECV_DLENGTH:
697 /* TBD */
698 break;
699 case ISCSI_PARAM_HDRDGST_EN:
700 sscanf(buf, "%d", &value);
701 if (value) {
702 iser_err("DataDigest wasn't negotiated to None\n");
703 return -EPROTO;
704 }
705 break;
706 case ISCSI_PARAM_DATADGST_EN:
707 sscanf(buf, "%d", &value);
708 if (value) {
709 iser_err("DataDigest wasn't negotiated to None\n");
710 return -EPROTO;
711 }
712 break;
713 case ISCSI_PARAM_IFMARKER_EN:
714 sscanf(buf, "%d", &value);
715 if (value) {
716 iser_err("IFMarker wasn't negotiated to No\n");
717 return -EPROTO;
718 }
719 break;
720 case ISCSI_PARAM_OFMARKER_EN:
721 sscanf(buf, "%d", &value);
722 if (value) {
723 iser_err("OFMarker wasn't negotiated to No\n");
724 return -EPROTO;
725 }
726 break;
727 default:
728 return iscsi_set_param(cls_conn, param, buf, buflen);
729 }
730
731 return 0;
732 }
733
734 /**
735 * iscsi_iser_conn_get_stats() - get iscsi connection statistics
736 * @cls_conn: iscsi class connection
737 * @stats: iscsi stats to output
738 *
739 * Output connection statistics.
740 */
iscsi_iser_conn_get_stats(struct iscsi_cls_conn * cls_conn,struct iscsi_stats * stats)741 static void iscsi_iser_conn_get_stats(struct iscsi_cls_conn *cls_conn,
742 struct iscsi_stats *stats)
743 {
744 struct iscsi_conn *conn = cls_conn->dd_data;
745
746 stats->txdata_octets = conn->txdata_octets;
747 stats->rxdata_octets = conn->rxdata_octets;
748 stats->scsicmd_pdus = conn->scsicmd_pdus_cnt;
749 stats->dataout_pdus = conn->dataout_pdus_cnt;
750 stats->scsirsp_pdus = conn->scsirsp_pdus_cnt;
751 stats->datain_pdus = conn->datain_pdus_cnt; /* always 0 */
752 stats->r2t_pdus = conn->r2t_pdus_cnt; /* always 0 */
753 stats->tmfcmd_pdus = conn->tmfcmd_pdus_cnt;
754 stats->tmfrsp_pdus = conn->tmfrsp_pdus_cnt;
755 stats->custom_length = 0;
756 }
757
iscsi_iser_get_ep_param(struct iscsi_endpoint * ep,enum iscsi_param param,char * buf)758 static int iscsi_iser_get_ep_param(struct iscsi_endpoint *ep,
759 enum iscsi_param param, char *buf)
760 {
761 struct iser_conn *iser_conn = ep->dd_data;
762
763 switch (param) {
764 case ISCSI_PARAM_CONN_PORT:
765 case ISCSI_PARAM_CONN_ADDRESS:
766 if (!iser_conn || !iser_conn->ib_conn.cma_id)
767 return -ENOTCONN;
768
769 return iscsi_conn_get_addr_param((struct sockaddr_storage *)
770 &iser_conn->ib_conn.cma_id->route.addr.dst_addr,
771 param, buf);
772 default:
773 break;
774 }
775 return -ENOSYS;
776 }
777
778 /**
779 * iscsi_iser_ep_connect() - Initiate iSER connection establishment
780 * @shost: scsi_host
781 * @dst_addr: destination address
782 * @non_blocking: indicate if routine can block
783 *
784 * Allocate an iscsi endpoint, an iser_conn structure and bind them.
785 * After that start RDMA connection establishment via rdma_cm. We
786 * don't allocate iser_conn embedded in iscsi_endpoint since in teardown
787 * the endpoint will be destroyed at ep_disconnect while iser_conn will
788 * cleanup its resources asynchronuously.
789 *
790 * Return: iscsi_endpoint created by iscsi layer or ERR_PTR(error)
791 * if fails.
792 */
iscsi_iser_ep_connect(struct Scsi_Host * shost,struct sockaddr * dst_addr,int non_blocking)793 static struct iscsi_endpoint *iscsi_iser_ep_connect(struct Scsi_Host *shost,
794 struct sockaddr *dst_addr,
795 int non_blocking)
796 {
797 int err;
798 struct iser_conn *iser_conn;
799 struct iscsi_endpoint *ep;
800
801 ep = iscsi_create_endpoint(0);
802 if (!ep)
803 return ERR_PTR(-ENOMEM);
804
805 iser_conn = kzalloc(sizeof(*iser_conn), GFP_KERNEL);
806 if (!iser_conn) {
807 err = -ENOMEM;
808 goto failure;
809 }
810
811 ep->dd_data = iser_conn;
812 iser_conn->ep = ep;
813 iser_conn_init(iser_conn);
814
815 err = iser_connect(iser_conn, NULL, dst_addr, non_blocking);
816 if (err)
817 goto failure;
818
819 return ep;
820 failure:
821 iscsi_destroy_endpoint(ep);
822 return ERR_PTR(err);
823 }
824
825 /**
826 * iscsi_iser_ep_poll() - poll for iser connection establishment to complete
827 * @ep: iscsi endpoint (created at ep_connect)
828 * @timeout_ms: polling timeout allowed in ms.
829 *
830 * This routine boils down to waiting for up_completion signaling
831 * that cma_id got CONNECTED event.
832 *
833 * Return: 1 if succeeded in connection establishment, 0 if timeout expired
834 * (libiscsi will retry will kick in) or -1 if interrupted by signal
835 * or more likely iser connection state transitioned to TEMINATING or
836 * DOWN during the wait period.
837 */
iscsi_iser_ep_poll(struct iscsi_endpoint * ep,int timeout_ms)838 static int iscsi_iser_ep_poll(struct iscsi_endpoint *ep, int timeout_ms)
839 {
840 struct iser_conn *iser_conn = ep->dd_data;
841 int rc;
842
843 rc = wait_for_completion_interruptible_timeout(&iser_conn->up_completion,
844 msecs_to_jiffies(timeout_ms));
845 /* if conn establishment failed, return error code to iscsi */
846 if (rc == 0) {
847 mutex_lock(&iser_conn->state_mutex);
848 if (iser_conn->state == ISER_CONN_TERMINATING ||
849 iser_conn->state == ISER_CONN_DOWN)
850 rc = -1;
851 mutex_unlock(&iser_conn->state_mutex);
852 }
853
854 iser_info("iser conn %p rc = %d\n", iser_conn, rc);
855
856 if (rc > 0)
857 return 1; /* success, this is the equivalent of EPOLLOUT */
858 else if (!rc)
859 return 0; /* timeout */
860 else
861 return rc; /* signal */
862 }
863
864 /**
865 * iscsi_iser_ep_disconnect() - Initiate connection teardown process
866 * @ep: iscsi endpoint handle
867 *
868 * This routine is not blocked by iser and RDMA termination process
869 * completion as we queue a deffered work for iser/RDMA destruction
870 * and cleanup or actually call it immediately in case we didn't pass
871 * iscsi conn bind/start stage, thus it is safe.
872 */
iscsi_iser_ep_disconnect(struct iscsi_endpoint * ep)873 static void iscsi_iser_ep_disconnect(struct iscsi_endpoint *ep)
874 {
875 struct iser_conn *iser_conn = ep->dd_data;
876
877 iser_info("ep %p iser conn %p\n", ep, iser_conn);
878
879 mutex_lock(&iser_conn->state_mutex);
880 iser_conn_terminate(iser_conn);
881
882 /*
883 * if iser_conn and iscsi_conn are bound, we must wait for
884 * iscsi_conn_stop and flush errors completion before freeing
885 * the iser resources. Otherwise we are safe to free resources
886 * immediately.
887 */
888 if (iser_conn->iscsi_conn) {
889 INIT_WORK(&iser_conn->release_work, iser_release_work);
890 queue_work(release_wq, &iser_conn->release_work);
891 mutex_unlock(&iser_conn->state_mutex);
892 } else {
893 iser_conn->state = ISER_CONN_DOWN;
894 mutex_unlock(&iser_conn->state_mutex);
895 iser_conn_release(iser_conn);
896 }
897
898 iscsi_destroy_endpoint(ep);
899 }
900
iser_attr_is_visible(int param_type,int param)901 static umode_t iser_attr_is_visible(int param_type, int param)
902 {
903 switch (param_type) {
904 case ISCSI_HOST_PARAM:
905 switch (param) {
906 case ISCSI_HOST_PARAM_NETDEV_NAME:
907 case ISCSI_HOST_PARAM_HWADDRESS:
908 case ISCSI_HOST_PARAM_INITIATOR_NAME:
909 return S_IRUGO;
910 default:
911 return 0;
912 }
913 case ISCSI_PARAM:
914 switch (param) {
915 case ISCSI_PARAM_MAX_RECV_DLENGTH:
916 case ISCSI_PARAM_MAX_XMIT_DLENGTH:
917 case ISCSI_PARAM_HDRDGST_EN:
918 case ISCSI_PARAM_DATADGST_EN:
919 case ISCSI_PARAM_CONN_ADDRESS:
920 case ISCSI_PARAM_CONN_PORT:
921 case ISCSI_PARAM_EXP_STATSN:
922 case ISCSI_PARAM_PERSISTENT_ADDRESS:
923 case ISCSI_PARAM_PERSISTENT_PORT:
924 case ISCSI_PARAM_PING_TMO:
925 case ISCSI_PARAM_RECV_TMO:
926 case ISCSI_PARAM_INITIAL_R2T_EN:
927 case ISCSI_PARAM_MAX_R2T:
928 case ISCSI_PARAM_IMM_DATA_EN:
929 case ISCSI_PARAM_FIRST_BURST:
930 case ISCSI_PARAM_MAX_BURST:
931 case ISCSI_PARAM_PDU_INORDER_EN:
932 case ISCSI_PARAM_DATASEQ_INORDER_EN:
933 case ISCSI_PARAM_TARGET_NAME:
934 case ISCSI_PARAM_TPGT:
935 case ISCSI_PARAM_USERNAME:
936 case ISCSI_PARAM_PASSWORD:
937 case ISCSI_PARAM_USERNAME_IN:
938 case ISCSI_PARAM_PASSWORD_IN:
939 case ISCSI_PARAM_FAST_ABORT:
940 case ISCSI_PARAM_ABORT_TMO:
941 case ISCSI_PARAM_LU_RESET_TMO:
942 case ISCSI_PARAM_TGT_RESET_TMO:
943 case ISCSI_PARAM_IFACE_NAME:
944 case ISCSI_PARAM_INITIATOR_NAME:
945 case ISCSI_PARAM_DISCOVERY_SESS:
946 return S_IRUGO;
947 default:
948 return 0;
949 }
950 }
951
952 return 0;
953 }
954
955 static const struct scsi_host_template iscsi_iser_sht = {
956 .module = THIS_MODULE,
957 .name = "iSCSI Initiator over iSER",
958 .queuecommand = iscsi_queuecommand,
959 .change_queue_depth = scsi_change_queue_depth,
960 .sg_tablesize = ISCSI_ISER_DEF_SG_TABLESIZE,
961 .cmd_per_lun = ISER_DEF_CMD_PER_LUN,
962 .eh_timed_out = iscsi_eh_cmd_timed_out,
963 .eh_abort_handler = iscsi_eh_abort,
964 .eh_device_reset_handler= iscsi_eh_device_reset,
965 .eh_target_reset_handler = iscsi_eh_recover_target,
966 .target_alloc = iscsi_target_alloc,
967 .proc_name = "iscsi_iser",
968 .this_id = -1,
969 .track_queue_depth = 1,
970 .cmd_size = sizeof(struct iscsi_cmd),
971 };
972
973 static struct iscsi_transport iscsi_iser_transport = {
974 .owner = THIS_MODULE,
975 .name = "iser",
976 .caps = CAP_RECOVERY_L0 | CAP_MULTI_R2T | CAP_TEXT_NEGO,
977 /* session management */
978 .create_session = iscsi_iser_session_create,
979 .destroy_session = iscsi_iser_session_destroy,
980 /* connection management */
981 .create_conn = iscsi_iser_conn_create,
982 .bind_conn = iscsi_iser_conn_bind,
983 .unbind_conn = iscsi_conn_unbind,
984 .destroy_conn = iscsi_conn_teardown,
985 .attr_is_visible = iser_attr_is_visible,
986 .set_param = iscsi_iser_set_param,
987 .get_conn_param = iscsi_conn_get_param,
988 .get_ep_param = iscsi_iser_get_ep_param,
989 .get_session_param = iscsi_session_get_param,
990 .start_conn = iscsi_iser_conn_start,
991 .stop_conn = iscsi_iser_conn_stop,
992 /* iscsi host params */
993 .get_host_param = iscsi_host_get_param,
994 .set_host_param = iscsi_host_set_param,
995 /* IO */
996 .send_pdu = iscsi_conn_send_pdu,
997 .get_stats = iscsi_iser_conn_get_stats,
998 .init_task = iscsi_iser_task_init,
999 .xmit_task = iscsi_iser_task_xmit,
1000 .cleanup_task = iscsi_iser_cleanup_task,
1001 .alloc_pdu = iscsi_iser_pdu_alloc,
1002 .check_protection = iscsi_iser_check_protection,
1003 /* recovery */
1004 .session_recovery_timedout = iscsi_session_recovery_timedout,
1005
1006 .ep_connect = iscsi_iser_ep_connect,
1007 .ep_poll = iscsi_iser_ep_poll,
1008 .ep_disconnect = iscsi_iser_ep_disconnect
1009 };
1010
iser_init(void)1011 static int __init iser_init(void)
1012 {
1013 int err;
1014
1015 iser_dbg("Starting iSER datamover...\n");
1016
1017 memset(&ig, 0, sizeof(struct iser_global));
1018
1019 ig.desc_cache = kmem_cache_create("iser_descriptors",
1020 sizeof(struct iser_tx_desc),
1021 0, SLAB_HWCACHE_ALIGN,
1022 NULL);
1023 if (ig.desc_cache == NULL)
1024 return -ENOMEM;
1025
1026 /* device init is called only after the first addr resolution */
1027 mutex_init(&ig.device_list_mutex);
1028 INIT_LIST_HEAD(&ig.device_list);
1029 mutex_init(&ig.connlist_mutex);
1030 INIT_LIST_HEAD(&ig.connlist);
1031
1032 release_wq = alloc_workqueue("release workqueue", 0, 0);
1033 if (!release_wq) {
1034 iser_err("failed to allocate release workqueue\n");
1035 err = -ENOMEM;
1036 goto err_alloc_wq;
1037 }
1038
1039 iscsi_iser_scsi_transport = iscsi_register_transport(
1040 &iscsi_iser_transport);
1041 if (!iscsi_iser_scsi_transport) {
1042 iser_err("iscsi_register_transport failed\n");
1043 err = -EINVAL;
1044 goto err_reg;
1045 }
1046
1047 return 0;
1048
1049 err_reg:
1050 destroy_workqueue(release_wq);
1051 err_alloc_wq:
1052 kmem_cache_destroy(ig.desc_cache);
1053
1054 return err;
1055 }
1056
iser_exit(void)1057 static void __exit iser_exit(void)
1058 {
1059 struct iser_conn *iser_conn, *n;
1060 int connlist_empty;
1061
1062 iser_dbg("Removing iSER datamover...\n");
1063 destroy_workqueue(release_wq);
1064
1065 mutex_lock(&ig.connlist_mutex);
1066 connlist_empty = list_empty(&ig.connlist);
1067 mutex_unlock(&ig.connlist_mutex);
1068
1069 if (!connlist_empty) {
1070 iser_err("Error cleanup stage completed but we still have iser "
1071 "connections, destroying them anyway\n");
1072 list_for_each_entry_safe(iser_conn, n, &ig.connlist,
1073 conn_list) {
1074 iser_conn_release(iser_conn);
1075 }
1076 }
1077
1078 iscsi_unregister_transport(&iscsi_iser_transport);
1079 kmem_cache_destroy(ig.desc_cache);
1080 }
1081
1082 module_init(iser_init);
1083 module_exit(iser_exit);
1084