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