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 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
116 int iser_pi_guard;
117 module_param_named(pi_guard, iser_pi_guard, int, S_IRUGO);
118 MODULE_PARM_DESC(pi_guard, "T10-PI guard_type [deprecated]");
119
iscsi_iser_set(const char * val,const struct kernel_param * kp)120 static int iscsi_iser_set(const char *val, const struct kernel_param *kp)
121 {
122 int ret;
123 unsigned int n = 0;
124
125 ret = kstrtouint(val, 10, &n);
126 if (ret != 0 || n == 0)
127 return -EINVAL;
128
129 return param_set_uint(val, kp);
130 }
131
132 /*
133 * iscsi_iser_recv() - Process a successful recv completion
134 * @conn: iscsi connection
135 * @hdr: iscsi header
136 * @rx_data: buffer containing receive data payload
137 * @rx_data_len: length of rx_data
138 *
139 * Notes: In case of data length errors or iscsi PDU completion failures
140 * this routine will signal iscsi layer of connection failure.
141 */
142 void
iscsi_iser_recv(struct iscsi_conn * conn,struct iscsi_hdr * hdr,char * rx_data,int rx_data_len)143 iscsi_iser_recv(struct iscsi_conn *conn, struct iscsi_hdr *hdr,
144 char *rx_data, int rx_data_len)
145 {
146 int rc = 0;
147 int datalen;
148
149 /* verify PDU length */
150 datalen = ntoh24(hdr->dlength);
151 if (datalen > rx_data_len || (datalen + 4) < rx_data_len) {
152 iser_err("wrong datalen %d (hdr), %d (IB)\n",
153 datalen, rx_data_len);
154 rc = ISCSI_ERR_DATALEN;
155 goto error;
156 }
157
158 if (datalen != rx_data_len)
159 iser_dbg("aligned datalen (%d) hdr, %d (IB)\n",
160 datalen, rx_data_len);
161
162 rc = iscsi_complete_pdu(conn, hdr, rx_data, rx_data_len);
163 if (rc && rc != ISCSI_ERR_NO_SCSI_CMD)
164 goto error;
165
166 return;
167 error:
168 iscsi_conn_failure(conn, rc);
169 }
170
171 /**
172 * iscsi_iser_pdu_alloc() - allocate an iscsi-iser PDU
173 * @task: iscsi task
174 * @opcode: iscsi command opcode
175 *
176 * Netes: This routine can't fail, just assign iscsi task
177 * hdr and max hdr size.
178 */
179 static int
iscsi_iser_pdu_alloc(struct iscsi_task * task,uint8_t opcode)180 iscsi_iser_pdu_alloc(struct iscsi_task *task, uint8_t opcode)
181 {
182 struct iscsi_iser_task *iser_task = task->dd_data;
183
184 task->hdr = (struct iscsi_hdr *)&iser_task->desc.iscsi_header;
185 task->hdr_max = sizeof(iser_task->desc.iscsi_header);
186
187 return 0;
188 }
189
190 /**
191 * iser_initialize_task_headers() - Initialize task headers
192 * @task: iscsi task
193 * @tx_desc: iser tx descriptor
194 *
195 * Notes:
196 * This routine may race with iser teardown flow for scsi
197 * error handling TMFs. So for TMF we should acquire the
198 * state mutex to avoid dereferencing the IB device which
199 * may have already been terminated.
200 */
201 int
iser_initialize_task_headers(struct iscsi_task * task,struct iser_tx_desc * tx_desc)202 iser_initialize_task_headers(struct iscsi_task *task,
203 struct iser_tx_desc *tx_desc)
204 {
205 struct iser_conn *iser_conn = task->conn->dd_data;
206 struct iser_device *device = iser_conn->ib_conn.device;
207 struct iscsi_iser_task *iser_task = task->dd_data;
208 u64 dma_addr;
209
210 if (unlikely(iser_conn->state != ISER_CONN_UP))
211 return -ENODEV;
212
213 dma_addr = ib_dma_map_single(device->ib_device, (void *)tx_desc,
214 ISER_HEADERS_LEN, DMA_TO_DEVICE);
215 if (ib_dma_mapping_error(device->ib_device, dma_addr))
216 return -ENOMEM;
217
218 tx_desc->inv_wr.next = NULL;
219 tx_desc->reg_wr.wr.next = NULL;
220 tx_desc->mapped = true;
221 tx_desc->dma_addr = dma_addr;
222 tx_desc->tx_sg[0].addr = tx_desc->dma_addr;
223 tx_desc->tx_sg[0].length = ISER_HEADERS_LEN;
224 tx_desc->tx_sg[0].lkey = device->pd->local_dma_lkey;
225
226 iser_task->iser_conn = iser_conn;
227
228 return 0;
229 }
230
231 /**
232 * iscsi_iser_task_init() - Initialize iscsi-iser task
233 * @task: iscsi task
234 *
235 * Initialize the task for the scsi command or mgmt command.
236 *
237 * Return: Returns zero on success or -ENOMEM when failing
238 * to init task headers (dma mapping error).
239 */
240 static int
iscsi_iser_task_init(struct iscsi_task * task)241 iscsi_iser_task_init(struct iscsi_task *task)
242 {
243 struct iscsi_iser_task *iser_task = task->dd_data;
244 int ret;
245
246 ret = iser_initialize_task_headers(task, &iser_task->desc);
247 if (ret) {
248 iser_err("Failed to init task %p, err = %d\n",
249 iser_task, ret);
250 return ret;
251 }
252
253 /* mgmt task */
254 if (!task->sc)
255 return 0;
256
257 iser_task->command_sent = 0;
258 iser_task_rdma_init(iser_task);
259 iser_task->sc = task->sc;
260
261 return 0;
262 }
263
264 /**
265 * iscsi_iser_mtask_xmit() - xmit management (immediate) task
266 * @conn: iscsi connection
267 * @task: task management task
268 *
269 * Notes:
270 * The function can return -EAGAIN in which case caller must
271 * call it again later, or recover. '0' return code means successful
272 * xmit.
273 *
274 **/
275 static int
iscsi_iser_mtask_xmit(struct iscsi_conn * conn,struct iscsi_task * task)276 iscsi_iser_mtask_xmit(struct iscsi_conn *conn, struct iscsi_task *task)
277 {
278 int error = 0;
279
280 iser_dbg("mtask xmit [cid %d itt 0x%x]\n", conn->id, task->itt);
281
282 error = iser_send_control(conn, task);
283
284 /* since iser xmits control with zero copy, tasks can not be recycled
285 * right after sending them.
286 * The recycling scheme is based on whether a response is expected
287 * - if yes, the task is recycled at iscsi_complete_pdu
288 * - if no, the task is recycled at iser_snd_completion
289 */
290 return error;
291 }
292
293 static int
iscsi_iser_task_xmit_unsol_data(struct iscsi_conn * conn,struct iscsi_task * task)294 iscsi_iser_task_xmit_unsol_data(struct iscsi_conn *conn,
295 struct iscsi_task *task)
296 {
297 struct iscsi_r2t_info *r2t = &task->unsol_r2t;
298 struct iscsi_data hdr;
299 int error = 0;
300
301 /* Send data-out PDUs while there's still unsolicited data to send */
302 while (iscsi_task_has_unsol_data(task)) {
303 iscsi_prep_data_out_pdu(task, r2t, &hdr);
304 iser_dbg("Sending data-out: itt 0x%x, data count %d\n",
305 hdr.itt, r2t->data_count);
306
307 /* the buffer description has been passed with the command */
308 /* Send the command */
309 error = iser_send_data_out(conn, task, &hdr);
310 if (error) {
311 r2t->datasn--;
312 goto iscsi_iser_task_xmit_unsol_data_exit;
313 }
314 r2t->sent += r2t->data_count;
315 iser_dbg("Need to send %d more as data-out PDUs\n",
316 r2t->data_length - r2t->sent);
317 }
318
319 iscsi_iser_task_xmit_unsol_data_exit:
320 return error;
321 }
322
323 /**
324 * iscsi_iser_task_xmit() - xmit iscsi-iser task
325 * @task: iscsi task
326 *
327 * Return: zero on success or escalates $error on failure.
328 */
329 static int
iscsi_iser_task_xmit(struct iscsi_task * task)330 iscsi_iser_task_xmit(struct iscsi_task *task)
331 {
332 struct iscsi_conn *conn = task->conn;
333 struct iscsi_iser_task *iser_task = task->dd_data;
334 int error = 0;
335
336 if (!task->sc)
337 return iscsi_iser_mtask_xmit(conn, task);
338
339 if (task->sc->sc_data_direction == DMA_TO_DEVICE) {
340 BUG_ON(scsi_bufflen(task->sc) == 0);
341
342 iser_dbg("cmd [itt %x total %d imm %d unsol_data %d\n",
343 task->itt, scsi_bufflen(task->sc),
344 task->imm_count, task->unsol_r2t.data_length);
345 }
346
347 iser_dbg("ctask xmit [cid %d itt 0x%x]\n",
348 conn->id, task->itt);
349
350 /* Send the cmd PDU */
351 if (!iser_task->command_sent) {
352 error = iser_send_command(conn, task);
353 if (error)
354 goto iscsi_iser_task_xmit_exit;
355 iser_task->command_sent = 1;
356 }
357
358 /* Send unsolicited data-out PDU(s) if necessary */
359 if (iscsi_task_has_unsol_data(task))
360 error = iscsi_iser_task_xmit_unsol_data(conn, task);
361
362 iscsi_iser_task_xmit_exit:
363 return error;
364 }
365
366 /**
367 * iscsi_iser_cleanup_task() - cleanup an iscsi-iser task
368 * @task: iscsi task
369 *
370 * Notes: In case the RDMA device is already NULL (might have
371 * been removed in DEVICE_REMOVAL CM event it will bail-out
372 * without doing dma unmapping.
373 */
iscsi_iser_cleanup_task(struct iscsi_task * task)374 static void iscsi_iser_cleanup_task(struct iscsi_task *task)
375 {
376 struct iscsi_iser_task *iser_task = task->dd_data;
377 struct iser_tx_desc *tx_desc = &iser_task->desc;
378 struct iser_conn *iser_conn = task->conn->dd_data;
379 struct iser_device *device = iser_conn->ib_conn.device;
380
381 /* DEVICE_REMOVAL event might have already released the device */
382 if (!device)
383 return;
384
385 if (likely(tx_desc->mapped)) {
386 ib_dma_unmap_single(device->ib_device, tx_desc->dma_addr,
387 ISER_HEADERS_LEN, DMA_TO_DEVICE);
388 tx_desc->mapped = false;
389 }
390
391 /* mgmt tasks do not need special cleanup */
392 if (!task->sc)
393 return;
394
395 if (iser_task->status == ISER_TASK_STATUS_STARTED) {
396 iser_task->status = ISER_TASK_STATUS_COMPLETED;
397 iser_task_rdma_finalize(iser_task);
398 }
399 }
400
401 /**
402 * iscsi_iser_check_protection() - check protection information status of task.
403 * @task: iscsi task
404 * @sector: error sector if exsists (output)
405 *
406 * Return: zero if no data-integrity errors have occured
407 * 0x1: data-integrity error occured in the guard-block
408 * 0x2: data-integrity error occured in the reference tag
409 * 0x3: data-integrity error occured in the application tag
410 *
411 * In addition the error sector is marked.
412 */
413 static u8
iscsi_iser_check_protection(struct iscsi_task * task,sector_t * sector)414 iscsi_iser_check_protection(struct iscsi_task *task, sector_t *sector)
415 {
416 struct iscsi_iser_task *iser_task = task->dd_data;
417 enum iser_data_dir dir = iser_task->dir[ISER_DIR_IN] ?
418 ISER_DIR_IN : ISER_DIR_OUT;
419
420 return iser_check_task_pi_status(iser_task, dir, sector);
421 }
422
423 /**
424 * iscsi_iser_conn_create() - create a new iscsi-iser connection
425 * @cls_session: iscsi class connection
426 * @conn_idx: connection index within the session (for MCS)
427 *
428 * Return: iscsi_cls_conn when iscsi_conn_setup succeeds or NULL
429 * otherwise.
430 */
431 static struct iscsi_cls_conn *
iscsi_iser_conn_create(struct iscsi_cls_session * cls_session,uint32_t conn_idx)432 iscsi_iser_conn_create(struct iscsi_cls_session *cls_session,
433 uint32_t conn_idx)
434 {
435 struct iscsi_conn *conn;
436 struct iscsi_cls_conn *cls_conn;
437
438 cls_conn = iscsi_conn_setup(cls_session, 0, conn_idx);
439 if (!cls_conn)
440 return NULL;
441 conn = cls_conn->dd_data;
442
443 /*
444 * due to issues with the login code re iser sematics
445 * this not set in iscsi_conn_setup - FIXME
446 */
447 conn->max_recv_dlength = ISER_RECV_DATA_SEG_LEN;
448
449 return cls_conn;
450 }
451
452 /**
453 * iscsi_iser_conn_bind() - bind iscsi and iser connection structures
454 * @cls_session: iscsi class session
455 * @cls_conn: iscsi class connection
456 * @transport_eph: transport end-point handle
457 * @is_leading: indicate if this is the session leading connection (MCS)
458 *
459 * Return: zero on success, $error if iscsi_conn_bind fails and
460 * -EINVAL in case end-point doesn't exsits anymore or iser connection
461 * state is not UP (teardown already started).
462 */
463 static int
iscsi_iser_conn_bind(struct iscsi_cls_session * cls_session,struct iscsi_cls_conn * cls_conn,uint64_t transport_eph,int is_leading)464 iscsi_iser_conn_bind(struct iscsi_cls_session *cls_session,
465 struct iscsi_cls_conn *cls_conn,
466 uint64_t transport_eph,
467 int is_leading)
468 {
469 struct iscsi_conn *conn = cls_conn->dd_data;
470 struct iser_conn *iser_conn;
471 struct iscsi_endpoint *ep;
472 int error;
473
474 error = iscsi_conn_bind(cls_session, cls_conn, is_leading);
475 if (error)
476 return error;
477
478 /* the transport ep handle comes from user space so it must be
479 * verified against the global ib connections list */
480 ep = iscsi_lookup_endpoint(transport_eph);
481 if (!ep) {
482 iser_err("can't bind eph %llx\n",
483 (unsigned long long)transport_eph);
484 return -EINVAL;
485 }
486 iser_conn = ep->dd_data;
487
488 mutex_lock(&iser_conn->state_mutex);
489 if (iser_conn->state != ISER_CONN_UP) {
490 error = -EINVAL;
491 iser_err("iser_conn %p state is %d, teardown started\n",
492 iser_conn, iser_conn->state);
493 goto out;
494 }
495
496 error = iser_alloc_rx_descriptors(iser_conn, conn->session);
497 if (error)
498 goto out;
499
500 /* binds the iSER connection retrieved from the previously
501 * connected ep_handle to the iSCSI layer connection. exchanges
502 * connection pointers */
503 iser_info("binding iscsi conn %p to iser_conn %p\n", conn, iser_conn);
504
505 conn->dd_data = iser_conn;
506 iser_conn->iscsi_conn = conn;
507
508 out:
509 mutex_unlock(&iser_conn->state_mutex);
510 return error;
511 }
512
513 /**
514 * iscsi_iser_conn_start() - start iscsi-iser connection
515 * @cls_conn: iscsi class connection
516 *
517 * Notes: Here iser intialize (or re-initialize) stop_completion as
518 * from this point iscsi must call conn_stop in session/connection
519 * teardown so iser transport must wait for it.
520 */
521 static int
iscsi_iser_conn_start(struct iscsi_cls_conn * cls_conn)522 iscsi_iser_conn_start(struct iscsi_cls_conn *cls_conn)
523 {
524 struct iscsi_conn *iscsi_conn;
525 struct iser_conn *iser_conn;
526
527 iscsi_conn = cls_conn->dd_data;
528 iser_conn = iscsi_conn->dd_data;
529 reinit_completion(&iser_conn->stop_completion);
530
531 return iscsi_conn_start(cls_conn);
532 }
533
534 /**
535 * iscsi_iser_conn_stop() - stop iscsi-iser connection
536 * @cls_conn: iscsi class connection
537 * @flag: indicate if recover or terminate (passed as is)
538 *
539 * Notes: Calling iscsi_conn_stop might theoretically race with
540 * DEVICE_REMOVAL event and dereference a previously freed RDMA device
541 * handle, so we call it under iser the state lock to protect against
542 * this kind of race.
543 */
544 static void
iscsi_iser_conn_stop(struct iscsi_cls_conn * cls_conn,int flag)545 iscsi_iser_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
546 {
547 struct iscsi_conn *conn = cls_conn->dd_data;
548 struct iser_conn *iser_conn = conn->dd_data;
549
550 iser_info("stopping iscsi_conn: %p, iser_conn: %p\n", conn, iser_conn);
551
552 /*
553 * Userspace may have goofed up and not bound the connection or
554 * might have only partially setup the connection.
555 */
556 if (iser_conn) {
557 mutex_lock(&iser_conn->state_mutex);
558 mutex_lock(&unbind_iser_conn_mutex);
559 iser_conn_terminate(iser_conn);
560 iscsi_conn_stop(cls_conn, flag);
561
562 /* unbind */
563 iser_conn->iscsi_conn = NULL;
564 conn->dd_data = NULL;
565 mutex_unlock(&unbind_iser_conn_mutex);
566
567 complete(&iser_conn->stop_completion);
568 mutex_unlock(&iser_conn->state_mutex);
569 } else {
570 iscsi_conn_stop(cls_conn, flag);
571 }
572 }
573
574 /**
575 * iscsi_iser_session_destroy() - destroy iscsi-iser session
576 * @cls_session: iscsi class session
577 *
578 * Removes and free iscsi host.
579 */
580 static void
iscsi_iser_session_destroy(struct iscsi_cls_session * cls_session)581 iscsi_iser_session_destroy(struct iscsi_cls_session *cls_session)
582 {
583 struct Scsi_Host *shost = iscsi_session_to_shost(cls_session);
584
585 iscsi_session_teardown(cls_session);
586 iscsi_host_remove(shost);
587 iscsi_host_free(shost);
588 }
589
590 static inline unsigned int
iser_dif_prot_caps(int prot_caps)591 iser_dif_prot_caps(int prot_caps)
592 {
593 int ret = 0;
594
595 if (prot_caps & IB_PROT_T10DIF_TYPE_1)
596 ret |= SHOST_DIF_TYPE1_PROTECTION |
597 SHOST_DIX_TYPE0_PROTECTION |
598 SHOST_DIX_TYPE1_PROTECTION;
599 if (prot_caps & IB_PROT_T10DIF_TYPE_2)
600 ret |= SHOST_DIF_TYPE2_PROTECTION |
601 SHOST_DIX_TYPE2_PROTECTION;
602 if (prot_caps & IB_PROT_T10DIF_TYPE_3)
603 ret |= SHOST_DIF_TYPE3_PROTECTION |
604 SHOST_DIX_TYPE3_PROTECTION;
605
606 return ret;
607 }
608
609 /**
610 * iscsi_iser_session_create() - create an iscsi-iser session
611 * @ep: iscsi end-point handle
612 * @cmds_max: maximum commands in this session
613 * @qdepth: session command queue depth
614 * @initial_cmdsn: initiator command sequnce number
615 *
616 * Allocates and adds a scsi host, expose DIF supprot if
617 * exists, and sets up an iscsi session.
618 */
619 static struct iscsi_cls_session *
iscsi_iser_session_create(struct iscsi_endpoint * ep,uint16_t cmds_max,uint16_t qdepth,uint32_t initial_cmdsn)620 iscsi_iser_session_create(struct iscsi_endpoint *ep,
621 uint16_t cmds_max, uint16_t qdepth,
622 uint32_t initial_cmdsn)
623 {
624 struct iscsi_cls_session *cls_session;
625 struct Scsi_Host *shost;
626 struct iser_conn *iser_conn = NULL;
627 struct ib_conn *ib_conn;
628 struct ib_device *ib_dev;
629 u32 max_fr_sectors;
630
631 shost = iscsi_host_alloc(&iscsi_iser_sht, 0, 0);
632 if (!shost)
633 return NULL;
634 shost->transportt = iscsi_iser_scsi_transport;
635 shost->cmd_per_lun = qdepth;
636 shost->max_lun = iscsi_max_lun;
637 shost->max_id = 0;
638 shost->max_channel = 0;
639 shost->max_cmd_len = 16;
640
641 /*
642 * older userspace tools (before 2.0-870) did not pass us
643 * the leading conn's ep so this will be NULL;
644 */
645 if (ep) {
646 iser_conn = ep->dd_data;
647 shost->sg_tablesize = iser_conn->scsi_sg_tablesize;
648 shost->can_queue = min_t(u16, cmds_max, iser_conn->max_cmds);
649
650 mutex_lock(&iser_conn->state_mutex);
651 if (iser_conn->state != ISER_CONN_UP) {
652 iser_err("iser conn %p already started teardown\n",
653 iser_conn);
654 mutex_unlock(&iser_conn->state_mutex);
655 goto free_host;
656 }
657
658 ib_conn = &iser_conn->ib_conn;
659 ib_dev = ib_conn->device->ib_device;
660 if (ib_conn->pi_support) {
661 u32 sig_caps = ib_dev->attrs.sig_prot_cap;
662
663 shost->sg_prot_tablesize = shost->sg_tablesize;
664 scsi_host_set_prot(shost, iser_dif_prot_caps(sig_caps));
665 scsi_host_set_guard(shost, SHOST_DIX_GUARD_IP |
666 SHOST_DIX_GUARD_CRC);
667 }
668
669 if (!(ib_dev->attrs.device_cap_flags & IB_DEVICE_SG_GAPS_REG))
670 shost->virt_boundary_mask = SZ_4K - 1;
671
672 if (iscsi_host_add(shost, ib_dev->dev.parent)) {
673 mutex_unlock(&iser_conn->state_mutex);
674 goto free_host;
675 }
676 mutex_unlock(&iser_conn->state_mutex);
677 } else {
678 shost->can_queue = min_t(u16, cmds_max, ISER_DEF_XMIT_CMDS_MAX);
679 if (iscsi_host_add(shost, NULL))
680 goto free_host;
681 }
682
683 max_fr_sectors = (shost->sg_tablesize * PAGE_SIZE) >> 9;
684 shost->max_sectors = min(iser_max_sectors, max_fr_sectors);
685
686 iser_dbg("iser_conn %p, sg_tablesize %u, max_sectors %u\n",
687 iser_conn, shost->sg_tablesize,
688 shost->max_sectors);
689
690 if (shost->max_sectors < iser_max_sectors)
691 iser_warn("max_sectors was reduced from %u to %u\n",
692 iser_max_sectors, shost->max_sectors);
693
694 cls_session = iscsi_session_setup(&iscsi_iser_transport, shost,
695 shost->can_queue, 0,
696 sizeof(struct iscsi_iser_task),
697 initial_cmdsn, 0);
698 if (!cls_session)
699 goto remove_host;
700
701 return cls_session;
702
703 remove_host:
704 iscsi_host_remove(shost);
705 free_host:
706 iscsi_host_free(shost);
707 return NULL;
708 }
709
710 static int
iscsi_iser_set_param(struct iscsi_cls_conn * cls_conn,enum iscsi_param param,char * buf,int buflen)711 iscsi_iser_set_param(struct iscsi_cls_conn *cls_conn,
712 enum iscsi_param param, char *buf, int buflen)
713 {
714 int value;
715
716 switch (param) {
717 case ISCSI_PARAM_MAX_RECV_DLENGTH:
718 /* TBD */
719 break;
720 case ISCSI_PARAM_HDRDGST_EN:
721 sscanf(buf, "%d", &value);
722 if (value) {
723 iser_err("DataDigest wasn't negotiated to None\n");
724 return -EPROTO;
725 }
726 break;
727 case ISCSI_PARAM_DATADGST_EN:
728 sscanf(buf, "%d", &value);
729 if (value) {
730 iser_err("DataDigest wasn't negotiated to None\n");
731 return -EPROTO;
732 }
733 break;
734 case ISCSI_PARAM_IFMARKER_EN:
735 sscanf(buf, "%d", &value);
736 if (value) {
737 iser_err("IFMarker wasn't negotiated to No\n");
738 return -EPROTO;
739 }
740 break;
741 case ISCSI_PARAM_OFMARKER_EN:
742 sscanf(buf, "%d", &value);
743 if (value) {
744 iser_err("OFMarker wasn't negotiated to No\n");
745 return -EPROTO;
746 }
747 break;
748 default:
749 return iscsi_set_param(cls_conn, param, buf, buflen);
750 }
751
752 return 0;
753 }
754
755 /**
756 * iscsi_iser_conn_get_stats() - get iscsi connection statistics
757 * @cls_conn: iscsi class connection
758 * @stats: iscsi stats to output
759 *
760 * Output connection statistics.
761 */
762 static void
iscsi_iser_conn_get_stats(struct iscsi_cls_conn * cls_conn,struct iscsi_stats * stats)763 iscsi_iser_conn_get_stats(struct iscsi_cls_conn *cls_conn, struct iscsi_stats *stats)
764 {
765 struct iscsi_conn *conn = cls_conn->dd_data;
766
767 stats->txdata_octets = conn->txdata_octets;
768 stats->rxdata_octets = conn->rxdata_octets;
769 stats->scsicmd_pdus = conn->scsicmd_pdus_cnt;
770 stats->dataout_pdus = conn->dataout_pdus_cnt;
771 stats->scsirsp_pdus = conn->scsirsp_pdus_cnt;
772 stats->datain_pdus = conn->datain_pdus_cnt; /* always 0 */
773 stats->r2t_pdus = conn->r2t_pdus_cnt; /* always 0 */
774 stats->tmfcmd_pdus = conn->tmfcmd_pdus_cnt;
775 stats->tmfrsp_pdus = conn->tmfrsp_pdus_cnt;
776 stats->custom_length = 0;
777 }
778
iscsi_iser_get_ep_param(struct iscsi_endpoint * ep,enum iscsi_param param,char * buf)779 static int iscsi_iser_get_ep_param(struct iscsi_endpoint *ep,
780 enum iscsi_param param, char *buf)
781 {
782 struct iser_conn *iser_conn = ep->dd_data;
783
784 switch (param) {
785 case ISCSI_PARAM_CONN_PORT:
786 case ISCSI_PARAM_CONN_ADDRESS:
787 if (!iser_conn || !iser_conn->ib_conn.cma_id)
788 return -ENOTCONN;
789
790 return iscsi_conn_get_addr_param((struct sockaddr_storage *)
791 &iser_conn->ib_conn.cma_id->route.addr.dst_addr,
792 param, buf);
793 default:
794 break;
795 }
796 return -ENOSYS;
797 }
798
799 /**
800 * iscsi_iser_ep_connect() - Initiate iSER connection establishment
801 * @shost: scsi_host
802 * @dst_addr: destination address
803 * @non_blocking: indicate if routine can block
804 *
805 * Allocate an iscsi endpoint, an iser_conn structure and bind them.
806 * After that start RDMA connection establishment via rdma_cm. We
807 * don't allocate iser_conn embedded in iscsi_endpoint since in teardown
808 * the endpoint will be destroyed at ep_disconnect while iser_conn will
809 * cleanup its resources asynchronuously.
810 *
811 * Return: iscsi_endpoint created by iscsi layer or ERR_PTR(error)
812 * if fails.
813 */
814 static struct iscsi_endpoint *
iscsi_iser_ep_connect(struct Scsi_Host * shost,struct sockaddr * dst_addr,int non_blocking)815 iscsi_iser_ep_connect(struct Scsi_Host *shost, struct sockaddr *dst_addr,
816 int non_blocking)
817 {
818 int err;
819 struct iser_conn *iser_conn;
820 struct iscsi_endpoint *ep;
821
822 ep = iscsi_create_endpoint(0);
823 if (!ep)
824 return ERR_PTR(-ENOMEM);
825
826 iser_conn = kzalloc(sizeof(*iser_conn), GFP_KERNEL);
827 if (!iser_conn) {
828 err = -ENOMEM;
829 goto failure;
830 }
831
832 ep->dd_data = iser_conn;
833 iser_conn->ep = ep;
834 iser_conn_init(iser_conn);
835
836 err = iser_connect(iser_conn, NULL, dst_addr, non_blocking);
837 if (err)
838 goto failure;
839
840 return ep;
841 failure:
842 iscsi_destroy_endpoint(ep);
843 return ERR_PTR(err);
844 }
845
846 /**
847 * iscsi_iser_ep_poll() - poll for iser connection establishment to complete
848 * @ep: iscsi endpoint (created at ep_connect)
849 * @timeout_ms: polling timeout allowed in ms.
850 *
851 * This routine boils down to waiting for up_completion signaling
852 * that cma_id got CONNECTED event.
853 *
854 * Return: 1 if succeeded in connection establishment, 0 if timeout expired
855 * (libiscsi will retry will kick in) or -1 if interrupted by signal
856 * or more likely iser connection state transitioned to TEMINATING or
857 * DOWN during the wait period.
858 */
859 static int
iscsi_iser_ep_poll(struct iscsi_endpoint * ep,int timeout_ms)860 iscsi_iser_ep_poll(struct iscsi_endpoint *ep, int timeout_ms)
861 {
862 struct iser_conn *iser_conn = ep->dd_data;
863 int rc;
864
865 rc = wait_for_completion_interruptible_timeout(&iser_conn->up_completion,
866 msecs_to_jiffies(timeout_ms));
867 /* if conn establishment failed, return error code to iscsi */
868 if (rc == 0) {
869 mutex_lock(&iser_conn->state_mutex);
870 if (iser_conn->state == ISER_CONN_TERMINATING ||
871 iser_conn->state == ISER_CONN_DOWN)
872 rc = -1;
873 mutex_unlock(&iser_conn->state_mutex);
874 }
875
876 iser_info("iser conn %p rc = %d\n", iser_conn, rc);
877
878 if (rc > 0)
879 return 1; /* success, this is the equivalent of EPOLLOUT */
880 else if (!rc)
881 return 0; /* timeout */
882 else
883 return rc; /* signal */
884 }
885
886 /**
887 * iscsi_iser_ep_disconnect() - Initiate connection teardown process
888 * @ep: iscsi endpoint handle
889 *
890 * This routine is not blocked by iser and RDMA termination process
891 * completion as we queue a deffered work for iser/RDMA destruction
892 * and cleanup or actually call it immediately in case we didn't pass
893 * iscsi conn bind/start stage, thus it is safe.
894 */
895 static void
iscsi_iser_ep_disconnect(struct iscsi_endpoint * ep)896 iscsi_iser_ep_disconnect(struct iscsi_endpoint *ep)
897 {
898 struct iser_conn *iser_conn = ep->dd_data;
899
900 iser_info("ep %p iser conn %p\n", ep, iser_conn);
901
902 mutex_lock(&iser_conn->state_mutex);
903 iser_conn_terminate(iser_conn);
904
905 /*
906 * if iser_conn and iscsi_conn are bound, we must wait for
907 * iscsi_conn_stop and flush errors completion before freeing
908 * the iser resources. Otherwise we are safe to free resources
909 * immediately.
910 */
911 if (iser_conn->iscsi_conn) {
912 INIT_WORK(&iser_conn->release_work, iser_release_work);
913 queue_work(release_wq, &iser_conn->release_work);
914 mutex_unlock(&iser_conn->state_mutex);
915 } else {
916 iser_conn->state = ISER_CONN_DOWN;
917 mutex_unlock(&iser_conn->state_mutex);
918 iser_conn_release(iser_conn);
919 }
920
921 iscsi_destroy_endpoint(ep);
922 }
923
iser_attr_is_visible(int param_type,int param)924 static umode_t iser_attr_is_visible(int param_type, int param)
925 {
926 switch (param_type) {
927 case ISCSI_HOST_PARAM:
928 switch (param) {
929 case ISCSI_HOST_PARAM_NETDEV_NAME:
930 case ISCSI_HOST_PARAM_HWADDRESS:
931 case ISCSI_HOST_PARAM_INITIATOR_NAME:
932 return S_IRUGO;
933 default:
934 return 0;
935 }
936 case ISCSI_PARAM:
937 switch (param) {
938 case ISCSI_PARAM_MAX_RECV_DLENGTH:
939 case ISCSI_PARAM_MAX_XMIT_DLENGTH:
940 case ISCSI_PARAM_HDRDGST_EN:
941 case ISCSI_PARAM_DATADGST_EN:
942 case ISCSI_PARAM_CONN_ADDRESS:
943 case ISCSI_PARAM_CONN_PORT:
944 case ISCSI_PARAM_EXP_STATSN:
945 case ISCSI_PARAM_PERSISTENT_ADDRESS:
946 case ISCSI_PARAM_PERSISTENT_PORT:
947 case ISCSI_PARAM_PING_TMO:
948 case ISCSI_PARAM_RECV_TMO:
949 case ISCSI_PARAM_INITIAL_R2T_EN:
950 case ISCSI_PARAM_MAX_R2T:
951 case ISCSI_PARAM_IMM_DATA_EN:
952 case ISCSI_PARAM_FIRST_BURST:
953 case ISCSI_PARAM_MAX_BURST:
954 case ISCSI_PARAM_PDU_INORDER_EN:
955 case ISCSI_PARAM_DATASEQ_INORDER_EN:
956 case ISCSI_PARAM_TARGET_NAME:
957 case ISCSI_PARAM_TPGT:
958 case ISCSI_PARAM_USERNAME:
959 case ISCSI_PARAM_PASSWORD:
960 case ISCSI_PARAM_USERNAME_IN:
961 case ISCSI_PARAM_PASSWORD_IN:
962 case ISCSI_PARAM_FAST_ABORT:
963 case ISCSI_PARAM_ABORT_TMO:
964 case ISCSI_PARAM_LU_RESET_TMO:
965 case ISCSI_PARAM_TGT_RESET_TMO:
966 case ISCSI_PARAM_IFACE_NAME:
967 case ISCSI_PARAM_INITIATOR_NAME:
968 case ISCSI_PARAM_DISCOVERY_SESS:
969 return S_IRUGO;
970 default:
971 return 0;
972 }
973 }
974
975 return 0;
976 }
977
978 static struct scsi_host_template iscsi_iser_sht = {
979 .module = THIS_MODULE,
980 .name = "iSCSI Initiator over iSER",
981 .queuecommand = iscsi_queuecommand,
982 .change_queue_depth = scsi_change_queue_depth,
983 .sg_tablesize = ISCSI_ISER_DEF_SG_TABLESIZE,
984 .cmd_per_lun = ISER_DEF_CMD_PER_LUN,
985 .eh_timed_out = iscsi_eh_cmd_timed_out,
986 .eh_abort_handler = iscsi_eh_abort,
987 .eh_device_reset_handler= iscsi_eh_device_reset,
988 .eh_target_reset_handler = iscsi_eh_recover_target,
989 .target_alloc = iscsi_target_alloc,
990 .proc_name = "iscsi_iser",
991 .this_id = -1,
992 .track_queue_depth = 1,
993 };
994
995 static struct iscsi_transport iscsi_iser_transport = {
996 .owner = THIS_MODULE,
997 .name = "iser",
998 .caps = CAP_RECOVERY_L0 | CAP_MULTI_R2T | CAP_TEXT_NEGO,
999 /* session management */
1000 .create_session = iscsi_iser_session_create,
1001 .destroy_session = iscsi_iser_session_destroy,
1002 /* connection management */
1003 .create_conn = iscsi_iser_conn_create,
1004 .bind_conn = iscsi_iser_conn_bind,
1005 .destroy_conn = iscsi_conn_teardown,
1006 .attr_is_visible = iser_attr_is_visible,
1007 .set_param = iscsi_iser_set_param,
1008 .get_conn_param = iscsi_conn_get_param,
1009 .get_ep_param = iscsi_iser_get_ep_param,
1010 .get_session_param = iscsi_session_get_param,
1011 .start_conn = iscsi_iser_conn_start,
1012 .stop_conn = iscsi_iser_conn_stop,
1013 /* iscsi host params */
1014 .get_host_param = iscsi_host_get_param,
1015 .set_host_param = iscsi_host_set_param,
1016 /* IO */
1017 .send_pdu = iscsi_conn_send_pdu,
1018 .get_stats = iscsi_iser_conn_get_stats,
1019 .init_task = iscsi_iser_task_init,
1020 .xmit_task = iscsi_iser_task_xmit,
1021 .cleanup_task = iscsi_iser_cleanup_task,
1022 .alloc_pdu = iscsi_iser_pdu_alloc,
1023 .check_protection = iscsi_iser_check_protection,
1024 /* recovery */
1025 .session_recovery_timedout = iscsi_session_recovery_timedout,
1026
1027 .ep_connect = iscsi_iser_ep_connect,
1028 .ep_poll = iscsi_iser_ep_poll,
1029 .ep_disconnect = iscsi_iser_ep_disconnect
1030 };
1031
iser_init(void)1032 static int __init iser_init(void)
1033 {
1034 int err;
1035
1036 iser_dbg("Starting iSER datamover...\n");
1037
1038 memset(&ig, 0, sizeof(struct iser_global));
1039
1040 ig.desc_cache = kmem_cache_create("iser_descriptors",
1041 sizeof(struct iser_tx_desc),
1042 0, SLAB_HWCACHE_ALIGN,
1043 NULL);
1044 if (ig.desc_cache == NULL)
1045 return -ENOMEM;
1046
1047 /* device init is called only after the first addr resolution */
1048 mutex_init(&ig.device_list_mutex);
1049 INIT_LIST_HEAD(&ig.device_list);
1050 mutex_init(&ig.connlist_mutex);
1051 INIT_LIST_HEAD(&ig.connlist);
1052
1053 release_wq = alloc_workqueue("release workqueue", 0, 0);
1054 if (!release_wq) {
1055 iser_err("failed to allocate release workqueue\n");
1056 err = -ENOMEM;
1057 goto err_alloc_wq;
1058 }
1059
1060 iscsi_iser_scsi_transport = iscsi_register_transport(
1061 &iscsi_iser_transport);
1062 if (!iscsi_iser_scsi_transport) {
1063 iser_err("iscsi_register_transport failed\n");
1064 err = -EINVAL;
1065 goto err_reg;
1066 }
1067
1068 return 0;
1069
1070 err_reg:
1071 destroy_workqueue(release_wq);
1072 err_alloc_wq:
1073 kmem_cache_destroy(ig.desc_cache);
1074
1075 return err;
1076 }
1077
iser_exit(void)1078 static void __exit iser_exit(void)
1079 {
1080 struct iser_conn *iser_conn, *n;
1081 int connlist_empty;
1082
1083 iser_dbg("Removing iSER datamover...\n");
1084 destroy_workqueue(release_wq);
1085
1086 mutex_lock(&ig.connlist_mutex);
1087 connlist_empty = list_empty(&ig.connlist);
1088 mutex_unlock(&ig.connlist_mutex);
1089
1090 if (!connlist_empty) {
1091 iser_err("Error cleanup stage completed but we still have iser "
1092 "connections, destroying them anyway\n");
1093 list_for_each_entry_safe(iser_conn, n, &ig.connlist,
1094 conn_list) {
1095 iser_conn_release(iser_conn);
1096 }
1097 }
1098
1099 iscsi_unregister_transport(&iscsi_iser_transport);
1100 kmem_cache_destroy(ig.desc_cache);
1101 }
1102
1103 module_init(iser_init);
1104 module_exit(iser_exit);
1105