xref: /openbmc/linux/drivers/s390/scsi/zfcp_scsi.c (revision f3956ebb)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * zfcp device driver
4  *
5  * Interface to Linux SCSI midlayer.
6  *
7  * Copyright IBM Corp. 2002, 2020
8  */
9 
10 #define KMSG_COMPONENT "zfcp"
11 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
12 
13 #include <linux/module.h>
14 #include <linux/types.h>
15 #include <linux/slab.h>
16 #include <scsi/fc/fc_fcp.h>
17 #include <scsi/scsi_eh.h>
18 #include <linux/atomic.h>
19 #include "zfcp_ext.h"
20 #include "zfcp_dbf.h"
21 #include "zfcp_fc.h"
22 #include "zfcp_reqlist.h"
23 
24 static unsigned int default_depth = 32;
25 module_param_named(queue_depth, default_depth, uint, 0600);
26 MODULE_PARM_DESC(queue_depth, "Default queue depth for new SCSI devices");
27 
28 static bool enable_dif;
29 module_param_named(dif, enable_dif, bool, 0400);
30 MODULE_PARM_DESC(dif, "Enable DIF data integrity support (default off)");
31 
32 bool zfcp_experimental_dix;
33 module_param_named(dix, zfcp_experimental_dix, bool, 0400);
34 MODULE_PARM_DESC(dix, "Enable experimental DIX (data integrity extension) support which implies DIF support (default off)");
35 
36 static bool allow_lun_scan = true;
37 module_param(allow_lun_scan, bool, 0600);
38 MODULE_PARM_DESC(allow_lun_scan, "For NPIV, scan and attach all storage LUNs");
39 
40 static void zfcp_scsi_slave_destroy(struct scsi_device *sdev)
41 {
42 	struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev);
43 
44 	/* if previous slave_alloc returned early, there is nothing to do */
45 	if (!zfcp_sdev->port)
46 		return;
47 
48 	zfcp_erp_lun_shutdown_wait(sdev, "scssd_1");
49 	put_device(&zfcp_sdev->port->dev);
50 }
51 
52 static int zfcp_scsi_slave_configure(struct scsi_device *sdp)
53 {
54 	if (sdp->tagged_supported)
55 		scsi_change_queue_depth(sdp, default_depth);
56 	return 0;
57 }
58 
59 static void zfcp_scsi_command_fail(struct scsi_cmnd *scpnt, int result)
60 {
61 	set_host_byte(scpnt, result);
62 	zfcp_dbf_scsi_fail_send(scpnt);
63 	scpnt->scsi_done(scpnt);
64 }
65 
66 static
67 int zfcp_scsi_queuecommand(struct Scsi_Host *shost, struct scsi_cmnd *scpnt)
68 {
69 	struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(scpnt->device);
70 	struct fc_rport *rport = starget_to_rport(scsi_target(scpnt->device));
71 	int    status, scsi_result, ret;
72 
73 	/* reset the status for this request */
74 	scpnt->result = 0;
75 	scpnt->host_scribble = NULL;
76 
77 	scsi_result = fc_remote_port_chkready(rport);
78 	if (unlikely(scsi_result)) {
79 		scpnt->result = scsi_result;
80 		zfcp_dbf_scsi_fail_send(scpnt);
81 		scpnt->scsi_done(scpnt);
82 		return 0;
83 	}
84 
85 	status = atomic_read(&zfcp_sdev->status);
86 	if (unlikely(status & ZFCP_STATUS_COMMON_ERP_FAILED) &&
87 		     !(atomic_read(&zfcp_sdev->port->status) &
88 		       ZFCP_STATUS_COMMON_ERP_FAILED)) {
89 		/* only LUN access denied, but port is good
90 		 * not covered by FC transport, have to fail here */
91 		zfcp_scsi_command_fail(scpnt, DID_ERROR);
92 		return 0;
93 	}
94 
95 	if (unlikely(!(status & ZFCP_STATUS_COMMON_UNBLOCKED))) {
96 		/* This could be
97 		 * call to rport_delete pending: mimic retry from
98 		 * 	fc_remote_port_chkready until rport is BLOCKED
99 		 */
100 		zfcp_scsi_command_fail(scpnt, DID_IMM_RETRY);
101 		return 0;
102 	}
103 
104 	ret = zfcp_fsf_fcp_cmnd(scpnt);
105 	if (unlikely(ret == -EBUSY))
106 		return SCSI_MLQUEUE_DEVICE_BUSY;
107 	else if (unlikely(ret < 0))
108 		return SCSI_MLQUEUE_HOST_BUSY;
109 
110 	return ret;
111 }
112 
113 static int zfcp_scsi_slave_alloc(struct scsi_device *sdev)
114 {
115 	struct fc_rport *rport = starget_to_rport(scsi_target(sdev));
116 	struct zfcp_adapter *adapter =
117 		(struct zfcp_adapter *) sdev->host->hostdata[0];
118 	struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev);
119 	struct zfcp_port *port;
120 	struct zfcp_unit *unit;
121 	int npiv = adapter->connection_features & FSF_FEATURE_NPIV_MODE;
122 
123 	zfcp_sdev->erp_action.adapter = adapter;
124 	zfcp_sdev->erp_action.sdev = sdev;
125 
126 	port = zfcp_get_port_by_wwpn(adapter, rport->port_name);
127 	if (!port)
128 		return -ENXIO;
129 
130 	zfcp_sdev->erp_action.port = port;
131 
132 	mutex_lock(&zfcp_sysfs_port_units_mutex);
133 	if (zfcp_sysfs_port_is_removing(port)) {
134 		/* port is already gone */
135 		mutex_unlock(&zfcp_sysfs_port_units_mutex);
136 		put_device(&port->dev); /* undo zfcp_get_port_by_wwpn() */
137 		return -ENXIO;
138 	}
139 	mutex_unlock(&zfcp_sysfs_port_units_mutex);
140 
141 	unit = zfcp_unit_find(port, zfcp_scsi_dev_lun(sdev));
142 	if (unit)
143 		put_device(&unit->dev);
144 
145 	if (!unit && !(allow_lun_scan && npiv)) {
146 		put_device(&port->dev);
147 		return -ENXIO;
148 	}
149 
150 	zfcp_sdev->port = port;
151 	zfcp_sdev->latencies.write.channel.min = 0xFFFFFFFF;
152 	zfcp_sdev->latencies.write.fabric.min = 0xFFFFFFFF;
153 	zfcp_sdev->latencies.read.channel.min = 0xFFFFFFFF;
154 	zfcp_sdev->latencies.read.fabric.min = 0xFFFFFFFF;
155 	zfcp_sdev->latencies.cmd.channel.min = 0xFFFFFFFF;
156 	zfcp_sdev->latencies.cmd.fabric.min = 0xFFFFFFFF;
157 	spin_lock_init(&zfcp_sdev->latencies.lock);
158 
159 	zfcp_erp_set_lun_status(sdev, ZFCP_STATUS_COMMON_RUNNING);
160 	zfcp_erp_lun_reopen(sdev, 0, "scsla_1");
161 	zfcp_erp_wait(port->adapter);
162 
163 	return 0;
164 }
165 
166 static int zfcp_scsi_eh_abort_handler(struct scsi_cmnd *scpnt)
167 {
168 	struct Scsi_Host *scsi_host = scpnt->device->host;
169 	struct zfcp_adapter *adapter =
170 		(struct zfcp_adapter *) scsi_host->hostdata[0];
171 	struct zfcp_fsf_req *old_req, *abrt_req;
172 	unsigned long flags;
173 	unsigned long old_reqid = (unsigned long) scpnt->host_scribble;
174 	int retval = SUCCESS, ret;
175 	int retry = 3;
176 	char *dbf_tag;
177 
178 	/* avoid race condition between late normal completion and abort */
179 	write_lock_irqsave(&adapter->abort_lock, flags);
180 
181 	old_req = zfcp_reqlist_find(adapter->req_list, old_reqid);
182 	if (!old_req) {
183 		write_unlock_irqrestore(&adapter->abort_lock, flags);
184 		zfcp_dbf_scsi_abort("abrt_or", scpnt, NULL);
185 		return FAILED; /* completion could be in progress */
186 	}
187 	old_req->data = NULL;
188 
189 	/* don't access old fsf_req after releasing the abort_lock */
190 	write_unlock_irqrestore(&adapter->abort_lock, flags);
191 
192 	while (retry--) {
193 		abrt_req = zfcp_fsf_abort_fcp_cmnd(scpnt);
194 		if (abrt_req)
195 			break;
196 
197 		zfcp_dbf_scsi_abort("abrt_wt", scpnt, NULL);
198 		zfcp_erp_wait(adapter);
199 		ret = fc_block_scsi_eh(scpnt);
200 		if (ret) {
201 			zfcp_dbf_scsi_abort("abrt_bl", scpnt, NULL);
202 			return ret;
203 		}
204 		if (!(atomic_read(&adapter->status) &
205 		      ZFCP_STATUS_COMMON_RUNNING)) {
206 			zfcp_dbf_scsi_abort("abrt_ru", scpnt, NULL);
207 			return SUCCESS;
208 		}
209 	}
210 	if (!abrt_req) {
211 		zfcp_dbf_scsi_abort("abrt_ar", scpnt, NULL);
212 		return FAILED;
213 	}
214 
215 	wait_for_completion(&abrt_req->completion);
216 
217 	if (abrt_req->status & ZFCP_STATUS_FSFREQ_ABORTSUCCEEDED)
218 		dbf_tag = "abrt_ok";
219 	else if (abrt_req->status & ZFCP_STATUS_FSFREQ_ABORTNOTNEEDED)
220 		dbf_tag = "abrt_nn";
221 	else {
222 		dbf_tag = "abrt_fa";
223 		retval = FAILED;
224 	}
225 	zfcp_dbf_scsi_abort(dbf_tag, scpnt, abrt_req);
226 	zfcp_fsf_req_free(abrt_req);
227 	return retval;
228 }
229 
230 struct zfcp_scsi_req_filter {
231 	u8 tmf_scope;
232 	u32 lun_handle;
233 	u32 port_handle;
234 };
235 
236 static void zfcp_scsi_forget_cmnd(struct zfcp_fsf_req *old_req, void *data)
237 {
238 	struct zfcp_scsi_req_filter *filter =
239 		(struct zfcp_scsi_req_filter *)data;
240 
241 	/* already aborted - prevent side-effects - or not a SCSI command */
242 	if (old_req->data == NULL ||
243 	    zfcp_fsf_req_is_status_read_buffer(old_req) ||
244 	    old_req->qtcb->header.fsf_command != FSF_QTCB_FCP_CMND)
245 		return;
246 
247 	/* (tmf_scope == FCP_TMF_TGT_RESET || tmf_scope == FCP_TMF_LUN_RESET) */
248 	if (old_req->qtcb->header.port_handle != filter->port_handle)
249 		return;
250 
251 	if (filter->tmf_scope == FCP_TMF_LUN_RESET &&
252 	    old_req->qtcb->header.lun_handle != filter->lun_handle)
253 		return;
254 
255 	zfcp_dbf_scsi_nullcmnd((struct scsi_cmnd *)old_req->data, old_req);
256 	old_req->data = NULL;
257 }
258 
259 static void zfcp_scsi_forget_cmnds(struct zfcp_scsi_dev *zsdev, u8 tm_flags)
260 {
261 	struct zfcp_adapter *adapter = zsdev->port->adapter;
262 	struct zfcp_scsi_req_filter filter = {
263 		.tmf_scope = FCP_TMF_TGT_RESET,
264 		.port_handle = zsdev->port->handle,
265 	};
266 	unsigned long flags;
267 
268 	if (tm_flags == FCP_TMF_LUN_RESET) {
269 		filter.tmf_scope = FCP_TMF_LUN_RESET;
270 		filter.lun_handle = zsdev->lun_handle;
271 	}
272 
273 	/*
274 	 * abort_lock secures against other processings - in the abort-function
275 	 * and normal cmnd-handler - of (struct zfcp_fsf_req *)->data
276 	 */
277 	write_lock_irqsave(&adapter->abort_lock, flags);
278 	zfcp_reqlist_apply_for_all(adapter->req_list, zfcp_scsi_forget_cmnd,
279 				   &filter);
280 	write_unlock_irqrestore(&adapter->abort_lock, flags);
281 }
282 
283 /**
284  * zfcp_scsi_task_mgmt_function() - Send a task management function (sync).
285  * @sdev: Pointer to SCSI device to send the task management command to.
286  * @tm_flags: Task management flags,
287  *	      here we only handle %FCP_TMF_TGT_RESET or %FCP_TMF_LUN_RESET.
288  */
289 static int zfcp_scsi_task_mgmt_function(struct scsi_device *sdev, u8 tm_flags)
290 {
291 	struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(sdev);
292 	struct zfcp_adapter *adapter = zfcp_sdev->port->adapter;
293 	struct fc_rport *rport = starget_to_rport(scsi_target(sdev));
294 	struct zfcp_fsf_req *fsf_req = NULL;
295 	int retval = SUCCESS, ret;
296 	int retry = 3;
297 
298 	while (retry--) {
299 		fsf_req = zfcp_fsf_fcp_task_mgmt(sdev, tm_flags);
300 		if (fsf_req)
301 			break;
302 
303 		zfcp_dbf_scsi_devreset("wait", sdev, tm_flags, NULL);
304 		zfcp_erp_wait(adapter);
305 		ret = fc_block_rport(rport);
306 		if (ret) {
307 			zfcp_dbf_scsi_devreset("fiof", sdev, tm_flags, NULL);
308 			return ret;
309 		}
310 
311 		if (!(atomic_read(&adapter->status) &
312 		      ZFCP_STATUS_COMMON_RUNNING)) {
313 			zfcp_dbf_scsi_devreset("nres", sdev, tm_flags, NULL);
314 			return SUCCESS;
315 		}
316 	}
317 	if (!fsf_req) {
318 		zfcp_dbf_scsi_devreset("reqf", sdev, tm_flags, NULL);
319 		return FAILED;
320 	}
321 
322 	wait_for_completion(&fsf_req->completion);
323 
324 	if (fsf_req->status & ZFCP_STATUS_FSFREQ_TMFUNCFAILED) {
325 		zfcp_dbf_scsi_devreset("fail", sdev, tm_flags, fsf_req);
326 		retval = FAILED;
327 	} else {
328 		zfcp_dbf_scsi_devreset("okay", sdev, tm_flags, fsf_req);
329 		zfcp_scsi_forget_cmnds(zfcp_sdev, tm_flags);
330 	}
331 
332 	zfcp_fsf_req_free(fsf_req);
333 	return retval;
334 }
335 
336 static int zfcp_scsi_eh_device_reset_handler(struct scsi_cmnd *scpnt)
337 {
338 	struct scsi_device *sdev = scpnt->device;
339 
340 	return zfcp_scsi_task_mgmt_function(sdev, FCP_TMF_LUN_RESET);
341 }
342 
343 static int zfcp_scsi_eh_target_reset_handler(struct scsi_cmnd *scpnt)
344 {
345 	struct scsi_target *starget = scsi_target(scpnt->device);
346 	struct fc_rport *rport = starget_to_rport(starget);
347 	struct Scsi_Host *shost = rport_to_shost(rport);
348 	struct scsi_device *sdev = NULL, *tmp_sdev;
349 	struct zfcp_adapter *adapter =
350 		(struct zfcp_adapter *)shost->hostdata[0];
351 	int ret;
352 
353 	shost_for_each_device(tmp_sdev, shost) {
354 		if (tmp_sdev->id == starget->id) {
355 			sdev = tmp_sdev;
356 			break;
357 		}
358 	}
359 	if (!sdev) {
360 		ret = FAILED;
361 		zfcp_dbf_scsi_eh("tr_nosd", adapter, starget->id, ret);
362 		return ret;
363 	}
364 
365 	ret = zfcp_scsi_task_mgmt_function(sdev, FCP_TMF_TGT_RESET);
366 
367 	/* release reference from above shost_for_each_device */
368 	if (sdev)
369 		scsi_device_put(tmp_sdev);
370 
371 	return ret;
372 }
373 
374 static int zfcp_scsi_eh_host_reset_handler(struct scsi_cmnd *scpnt)
375 {
376 	struct zfcp_scsi_dev *zfcp_sdev = sdev_to_zfcp(scpnt->device);
377 	struct zfcp_adapter *adapter = zfcp_sdev->port->adapter;
378 	int ret = SUCCESS, fc_ret;
379 
380 	if (!(adapter->connection_features & FSF_FEATURE_NPIV_MODE)) {
381 		zfcp_erp_port_forced_reopen_all(adapter, 0, "schrh_p");
382 		zfcp_erp_wait(adapter);
383 	}
384 	zfcp_erp_adapter_reopen(adapter, 0, "schrh_1");
385 	zfcp_erp_wait(adapter);
386 	fc_ret = fc_block_scsi_eh(scpnt);
387 	if (fc_ret)
388 		ret = fc_ret;
389 
390 	zfcp_dbf_scsi_eh("schrh_r", adapter, ~0, ret);
391 	return ret;
392 }
393 
394 /**
395  * zfcp_scsi_sysfs_host_reset() - Support scsi_host sysfs attribute host_reset.
396  * @shost: Pointer to Scsi_Host to perform action on.
397  * @reset_type: We support %SCSI_ADAPTER_RESET but not %SCSI_FIRMWARE_RESET.
398  *
399  * Return: 0 on %SCSI_ADAPTER_RESET, -%EOPNOTSUPP otherwise.
400  *
401  * This is similar to zfcp_sysfs_adapter_failed_store().
402  */
403 static int zfcp_scsi_sysfs_host_reset(struct Scsi_Host *shost, int reset_type)
404 {
405 	struct zfcp_adapter *adapter =
406 		(struct zfcp_adapter *)shost->hostdata[0];
407 	int ret = 0;
408 
409 	if (reset_type != SCSI_ADAPTER_RESET) {
410 		ret = -EOPNOTSUPP;
411 		zfcp_dbf_scsi_eh("scshr_n", adapter, ~0, ret);
412 		return ret;
413 	}
414 
415 	zfcp_erp_adapter_reset_sync(adapter, "scshr_y");
416 	return ret;
417 }
418 
419 struct scsi_transport_template *zfcp_scsi_transport_template;
420 
421 static struct scsi_host_template zfcp_scsi_host_template = {
422 	.module			 = THIS_MODULE,
423 	.name			 = "zfcp",
424 	.queuecommand		 = zfcp_scsi_queuecommand,
425 	.eh_timed_out		 = fc_eh_timed_out,
426 	.eh_abort_handler	 = zfcp_scsi_eh_abort_handler,
427 	.eh_device_reset_handler = zfcp_scsi_eh_device_reset_handler,
428 	.eh_target_reset_handler = zfcp_scsi_eh_target_reset_handler,
429 	.eh_host_reset_handler	 = zfcp_scsi_eh_host_reset_handler,
430 	.slave_alloc		 = zfcp_scsi_slave_alloc,
431 	.slave_configure	 = zfcp_scsi_slave_configure,
432 	.slave_destroy		 = zfcp_scsi_slave_destroy,
433 	.change_queue_depth	 = scsi_change_queue_depth,
434 	.host_reset		 = zfcp_scsi_sysfs_host_reset,
435 	.proc_name		 = "zfcp",
436 	.can_queue		 = 4096,
437 	.this_id		 = -1,
438 	.sg_tablesize		 = (((QDIO_MAX_ELEMENTS_PER_BUFFER - 1)
439 				     * ZFCP_QDIO_MAX_SBALS_PER_REQ) - 2),
440 				   /* GCD, adjusted later */
441 	.max_sectors		 = (((QDIO_MAX_ELEMENTS_PER_BUFFER - 1)
442 				     * ZFCP_QDIO_MAX_SBALS_PER_REQ) - 2) * 8,
443 				   /* GCD, adjusted later */
444 	/* report size limit per scatter-gather segment */
445 	.max_segment_size	 = ZFCP_QDIO_SBALE_LEN,
446 	.dma_boundary		 = ZFCP_QDIO_SBALE_LEN - 1,
447 	.shost_attrs		 = zfcp_sysfs_shost_attrs,
448 	.sdev_attrs		 = zfcp_sysfs_sdev_attrs,
449 	.track_queue_depth	 = 1,
450 	.supported_mode		 = MODE_INITIATOR,
451 };
452 
453 /**
454  * zfcp_scsi_adapter_register() - Allocate and register SCSI and FC host with
455  *				  SCSI midlayer
456  * @adapter: The zfcp adapter to register with the SCSI midlayer
457  *
458  * Allocates the SCSI host object for the given adapter, sets basic properties
459  * (such as the transport template, QDIO limits, ...), and registers it with
460  * the midlayer.
461  *
462  * During registration with the midlayer the corresponding FC host object for
463  * the referenced transport class is also implicitely allocated.
464  *
465  * Upon success adapter->scsi_host is set, and upon failure it remains NULL. If
466  * adapter->scsi_host is already set, nothing is done.
467  *
468  * Return:
469  * * 0	     - Allocation and registration was successful
470  * * -EEXIST - SCSI and FC host did already exist, nothing was done, nothing
471  *	       was changed
472  * * -EIO    - Allocation or registration failed
473  */
474 int zfcp_scsi_adapter_register(struct zfcp_adapter *adapter)
475 {
476 	struct ccw_dev_id dev_id;
477 
478 	if (adapter->scsi_host)
479 		return -EEXIST;
480 
481 	ccw_device_get_id(adapter->ccw_device, &dev_id);
482 	/* register adapter as SCSI host with mid layer of SCSI stack */
483 	adapter->scsi_host = scsi_host_alloc(&zfcp_scsi_host_template,
484 					     sizeof (struct zfcp_adapter *));
485 	if (!adapter->scsi_host)
486 		goto err_out;
487 
488 	/* tell the SCSI stack some characteristics of this adapter */
489 	adapter->scsi_host->max_id = 511;
490 	adapter->scsi_host->max_lun = 0xFFFFFFFF;
491 	adapter->scsi_host->max_channel = 0;
492 	adapter->scsi_host->unique_id = dev_id.devno;
493 	adapter->scsi_host->max_cmd_len = 16; /* in struct fcp_cmnd */
494 	adapter->scsi_host->transportt = zfcp_scsi_transport_template;
495 
496 	/* make all basic properties known at registration time */
497 	zfcp_qdio_shost_update(adapter, adapter->qdio);
498 	zfcp_scsi_set_prot(adapter);
499 
500 	adapter->scsi_host->hostdata[0] = (unsigned long) adapter;
501 
502 	if (scsi_add_host(adapter->scsi_host, &adapter->ccw_device->dev)) {
503 		scsi_host_put(adapter->scsi_host);
504 		goto err_out;
505 	}
506 
507 	return 0;
508 err_out:
509 	adapter->scsi_host = NULL;
510 	dev_err(&adapter->ccw_device->dev,
511 		"Registering the FCP device with the SCSI stack failed\n");
512 	return -EIO;
513 }
514 
515 /**
516  * zfcp_scsi_adapter_unregister - Unregister SCSI and FC host from SCSI midlayer
517  * @adapter: The zfcp adapter to unregister.
518  */
519 void zfcp_scsi_adapter_unregister(struct zfcp_adapter *adapter)
520 {
521 	struct Scsi_Host *shost;
522 	struct zfcp_port *port;
523 
524 	shost = adapter->scsi_host;
525 	if (!shost)
526 		return;
527 
528 	read_lock_irq(&adapter->port_list_lock);
529 	list_for_each_entry(port, &adapter->port_list, list)
530 		port->rport = NULL;
531 	read_unlock_irq(&adapter->port_list_lock);
532 
533 	fc_remove_host(shost);
534 	scsi_remove_host(shost);
535 	scsi_host_put(shost);
536 	adapter->scsi_host = NULL;
537 }
538 
539 static struct fc_host_statistics*
540 zfcp_scsi_init_fc_host_stats(struct zfcp_adapter *adapter)
541 {
542 	struct fc_host_statistics *fc_stats;
543 
544 	if (!adapter->fc_stats) {
545 		fc_stats = kmalloc(sizeof(*fc_stats), GFP_KERNEL);
546 		if (!fc_stats)
547 			return NULL;
548 		adapter->fc_stats = fc_stats; /* freed in adapter_release */
549 	}
550 	memset(adapter->fc_stats, 0, sizeof(*adapter->fc_stats));
551 	return adapter->fc_stats;
552 }
553 
554 static void zfcp_scsi_adjust_fc_host_stats(struct fc_host_statistics *fc_stats,
555 					   struct fsf_qtcb_bottom_port *data,
556 					   struct fsf_qtcb_bottom_port *old)
557 {
558 	fc_stats->seconds_since_last_reset =
559 		data->seconds_since_last_reset - old->seconds_since_last_reset;
560 	fc_stats->tx_frames = data->tx_frames - old->tx_frames;
561 	fc_stats->tx_words = data->tx_words - old->tx_words;
562 	fc_stats->rx_frames = data->rx_frames - old->rx_frames;
563 	fc_stats->rx_words = data->rx_words - old->rx_words;
564 	fc_stats->lip_count = data->lip - old->lip;
565 	fc_stats->nos_count = data->nos - old->nos;
566 	fc_stats->error_frames = data->error_frames - old->error_frames;
567 	fc_stats->dumped_frames = data->dumped_frames - old->dumped_frames;
568 	fc_stats->link_failure_count = data->link_failure - old->link_failure;
569 	fc_stats->loss_of_sync_count = data->loss_of_sync - old->loss_of_sync;
570 	fc_stats->loss_of_signal_count =
571 		data->loss_of_signal - old->loss_of_signal;
572 	fc_stats->prim_seq_protocol_err_count =
573 		data->psp_error_counts - old->psp_error_counts;
574 	fc_stats->invalid_tx_word_count =
575 		data->invalid_tx_words - old->invalid_tx_words;
576 	fc_stats->invalid_crc_count = data->invalid_crcs - old->invalid_crcs;
577 	fc_stats->fcp_input_requests =
578 		data->input_requests - old->input_requests;
579 	fc_stats->fcp_output_requests =
580 		data->output_requests - old->output_requests;
581 	fc_stats->fcp_control_requests =
582 		data->control_requests - old->control_requests;
583 	fc_stats->fcp_input_megabytes = data->input_mb - old->input_mb;
584 	fc_stats->fcp_output_megabytes = data->output_mb - old->output_mb;
585 }
586 
587 static void zfcp_scsi_set_fc_host_stats(struct fc_host_statistics *fc_stats,
588 					struct fsf_qtcb_bottom_port *data)
589 {
590 	fc_stats->seconds_since_last_reset = data->seconds_since_last_reset;
591 	fc_stats->tx_frames = data->tx_frames;
592 	fc_stats->tx_words = data->tx_words;
593 	fc_stats->rx_frames = data->rx_frames;
594 	fc_stats->rx_words = data->rx_words;
595 	fc_stats->lip_count = data->lip;
596 	fc_stats->nos_count = data->nos;
597 	fc_stats->error_frames = data->error_frames;
598 	fc_stats->dumped_frames = data->dumped_frames;
599 	fc_stats->link_failure_count = data->link_failure;
600 	fc_stats->loss_of_sync_count = data->loss_of_sync;
601 	fc_stats->loss_of_signal_count = data->loss_of_signal;
602 	fc_stats->prim_seq_protocol_err_count = data->psp_error_counts;
603 	fc_stats->invalid_tx_word_count = data->invalid_tx_words;
604 	fc_stats->invalid_crc_count = data->invalid_crcs;
605 	fc_stats->fcp_input_requests = data->input_requests;
606 	fc_stats->fcp_output_requests = data->output_requests;
607 	fc_stats->fcp_control_requests = data->control_requests;
608 	fc_stats->fcp_input_megabytes = data->input_mb;
609 	fc_stats->fcp_output_megabytes = data->output_mb;
610 }
611 
612 static struct fc_host_statistics *
613 zfcp_scsi_get_fc_host_stats(struct Scsi_Host *host)
614 {
615 	struct zfcp_adapter *adapter;
616 	struct fc_host_statistics *fc_stats;
617 	struct fsf_qtcb_bottom_port *data;
618 	int ret;
619 
620 	adapter = (struct zfcp_adapter *)host->hostdata[0];
621 	fc_stats = zfcp_scsi_init_fc_host_stats(adapter);
622 	if (!fc_stats)
623 		return NULL;
624 
625 	data = kzalloc(sizeof(*data), GFP_KERNEL);
626 	if (!data)
627 		return NULL;
628 
629 	ret = zfcp_fsf_exchange_port_data_sync(adapter->qdio, data);
630 	if (ret != 0 && ret != -EAGAIN) {
631 		kfree(data);
632 		return NULL;
633 	}
634 
635 	if (adapter->stats_reset &&
636 	    ((jiffies/HZ - adapter->stats_reset) <
637 	     data->seconds_since_last_reset))
638 		zfcp_scsi_adjust_fc_host_stats(fc_stats, data,
639 					       adapter->stats_reset_data);
640 	else
641 		zfcp_scsi_set_fc_host_stats(fc_stats, data);
642 
643 	kfree(data);
644 	return fc_stats;
645 }
646 
647 static void zfcp_scsi_reset_fc_host_stats(struct Scsi_Host *shost)
648 {
649 	struct zfcp_adapter *adapter;
650 	struct fsf_qtcb_bottom_port *data;
651 	int ret;
652 
653 	adapter = (struct zfcp_adapter *)shost->hostdata[0];
654 	data = kzalloc(sizeof(*data), GFP_KERNEL);
655 	if (!data)
656 		return;
657 
658 	ret = zfcp_fsf_exchange_port_data_sync(adapter->qdio, data);
659 	if (ret != 0 && ret != -EAGAIN)
660 		kfree(data);
661 	else {
662 		adapter->stats_reset = jiffies/HZ;
663 		kfree(adapter->stats_reset_data);
664 		adapter->stats_reset_data = data; /* finally freed in
665 						     adapter_release */
666 	}
667 }
668 
669 static void zfcp_scsi_get_host_port_state(struct Scsi_Host *shost)
670 {
671 	struct zfcp_adapter *adapter =
672 		(struct zfcp_adapter *)shost->hostdata[0];
673 	int status = atomic_read(&adapter->status);
674 
675 	if ((status & ZFCP_STATUS_COMMON_RUNNING) &&
676 	    !(status & ZFCP_STATUS_ADAPTER_LINK_UNPLUGGED))
677 		fc_host_port_state(shost) = FC_PORTSTATE_ONLINE;
678 	else if (status & ZFCP_STATUS_ADAPTER_LINK_UNPLUGGED)
679 		fc_host_port_state(shost) = FC_PORTSTATE_LINKDOWN;
680 	else if (status & ZFCP_STATUS_COMMON_ERP_FAILED)
681 		fc_host_port_state(shost) = FC_PORTSTATE_ERROR;
682 	else
683 		fc_host_port_state(shost) = FC_PORTSTATE_UNKNOWN;
684 }
685 
686 static void zfcp_scsi_set_rport_dev_loss_tmo(struct fc_rport *rport,
687 					     u32 timeout)
688 {
689 	rport->dev_loss_tmo = timeout;
690 }
691 
692 /**
693  * zfcp_scsi_terminate_rport_io - Terminate all I/O on a rport
694  * @rport: The FC rport where to teminate I/O
695  *
696  * Abort all pending SCSI commands for a port by closing the
697  * port. Using a reopen avoids a conflict with a shutdown
698  * overwriting a reopen. The "forced" ensures that a disappeared port
699  * is not opened again as valid due to the cached plogi data in
700  * non-NPIV mode.
701  */
702 static void zfcp_scsi_terminate_rport_io(struct fc_rport *rport)
703 {
704 	struct zfcp_port *port;
705 	struct Scsi_Host *shost = rport_to_shost(rport);
706 	struct zfcp_adapter *adapter =
707 		(struct zfcp_adapter *)shost->hostdata[0];
708 
709 	port = zfcp_get_port_by_wwpn(adapter, rport->port_name);
710 
711 	if (port) {
712 		zfcp_erp_port_forced_reopen(port, 0, "sctrpi1");
713 		put_device(&port->dev);
714 	} else {
715 		zfcp_erp_port_forced_no_port_dbf(
716 			"sctrpin", adapter,
717 			rport->port_name /* zfcp_scsi_rport_register */,
718 			rport->port_id /* zfcp_scsi_rport_register */);
719 	}
720 }
721 
722 static void zfcp_scsi_rport_register(struct zfcp_port *port)
723 {
724 	struct fc_rport_identifiers ids;
725 	struct fc_rport *rport;
726 
727 	if (port->rport)
728 		return;
729 
730 	ids.node_name = port->wwnn;
731 	ids.port_name = port->wwpn;
732 	ids.port_id = port->d_id;
733 	ids.roles = FC_RPORT_ROLE_FCP_TARGET;
734 
735 	zfcp_dbf_rec_trig_lock("scpaddy", port->adapter, port, NULL,
736 			       ZFCP_PSEUDO_ERP_ACTION_RPORT_ADD,
737 			       ZFCP_PSEUDO_ERP_ACTION_RPORT_ADD);
738 	rport = fc_remote_port_add(port->adapter->scsi_host, 0, &ids);
739 	if (!rport) {
740 		dev_err(&port->adapter->ccw_device->dev,
741 			"Registering port 0x%016Lx failed\n",
742 			(unsigned long long)port->wwpn);
743 		return;
744 	}
745 
746 	rport->maxframe_size = port->maxframe_size;
747 	rport->supported_classes = port->supported_classes;
748 	port->rport = rport;
749 	port->starget_id = rport->scsi_target_id;
750 
751 	zfcp_unit_queue_scsi_scan(port);
752 }
753 
754 static void zfcp_scsi_rport_block(struct zfcp_port *port)
755 {
756 	struct fc_rport *rport = port->rport;
757 
758 	if (rport) {
759 		zfcp_dbf_rec_trig_lock("scpdely", port->adapter, port, NULL,
760 				       ZFCP_PSEUDO_ERP_ACTION_RPORT_DEL,
761 				       ZFCP_PSEUDO_ERP_ACTION_RPORT_DEL);
762 		fc_remote_port_delete(rport);
763 		port->rport = NULL;
764 	}
765 }
766 
767 void zfcp_scsi_schedule_rport_register(struct zfcp_port *port)
768 {
769 	get_device(&port->dev);
770 	port->rport_task = RPORT_ADD;
771 
772 	if (!queue_work(port->adapter->work_queue, &port->rport_work))
773 		put_device(&port->dev);
774 }
775 
776 void zfcp_scsi_schedule_rport_block(struct zfcp_port *port)
777 {
778 	get_device(&port->dev);
779 	port->rport_task = RPORT_DEL;
780 
781 	if (port->rport && queue_work(port->adapter->work_queue,
782 				      &port->rport_work))
783 		return;
784 
785 	put_device(&port->dev);
786 }
787 
788 void zfcp_scsi_schedule_rports_block(struct zfcp_adapter *adapter)
789 {
790 	unsigned long flags;
791 	struct zfcp_port *port;
792 
793 	read_lock_irqsave(&adapter->port_list_lock, flags);
794 	list_for_each_entry(port, &adapter->port_list, list)
795 		zfcp_scsi_schedule_rport_block(port);
796 	read_unlock_irqrestore(&adapter->port_list_lock, flags);
797 }
798 
799 void zfcp_scsi_rport_work(struct work_struct *work)
800 {
801 	struct zfcp_port *port = container_of(work, struct zfcp_port,
802 					      rport_work);
803 
804 	set_worker_desc("zrp%c-%16llx",
805 			(port->rport_task == RPORT_ADD) ? 'a' : 'd',
806 			port->wwpn); /* < WORKER_DESC_LEN=24 */
807 	while (port->rport_task) {
808 		if (port->rport_task == RPORT_ADD) {
809 			port->rport_task = RPORT_NONE;
810 			zfcp_scsi_rport_register(port);
811 		} else {
812 			port->rport_task = RPORT_NONE;
813 			zfcp_scsi_rport_block(port);
814 		}
815 	}
816 
817 	put_device(&port->dev);
818 }
819 
820 /**
821  * zfcp_scsi_set_prot - Configure DIF/DIX support in scsi_host
822  * @adapter: The adapter where to configure DIF/DIX for the SCSI host
823  */
824 void zfcp_scsi_set_prot(struct zfcp_adapter *adapter)
825 {
826 	unsigned int mask = 0;
827 	unsigned int data_div;
828 	struct Scsi_Host *shost = adapter->scsi_host;
829 
830 	data_div = atomic_read(&adapter->status) &
831 		   ZFCP_STATUS_ADAPTER_DATA_DIV_ENABLED;
832 
833 	if ((enable_dif || zfcp_experimental_dix) &&
834 	    adapter->adapter_features & FSF_FEATURE_DIF_PROT_TYPE1)
835 		mask |= SHOST_DIF_TYPE1_PROTECTION;
836 
837 	if (zfcp_experimental_dix && data_div &&
838 	    adapter->adapter_features & FSF_FEATURE_DIX_PROT_TCPIP) {
839 		mask |= SHOST_DIX_TYPE1_PROTECTION;
840 		scsi_host_set_guard(shost, SHOST_DIX_GUARD_IP);
841 		shost->sg_prot_tablesize = adapter->qdio->max_sbale_per_req / 2;
842 		shost->sg_tablesize = adapter->qdio->max_sbale_per_req / 2;
843 		shost->max_sectors = shost->sg_tablesize * 8;
844 	}
845 
846 	scsi_host_set_prot(shost, mask);
847 }
848 
849 /**
850  * zfcp_scsi_dif_sense_error - Report DIF/DIX error as driver sense error
851  * @scmd: The SCSI command to report the error for
852  * @ascq: The ASCQ to put in the sense buffer
853  *
854  * See the error handling in sd_done for the sense codes used here.
855  * Set DID_SOFT_ERROR to retry the request, if possible.
856  */
857 void zfcp_scsi_dif_sense_error(struct scsi_cmnd *scmd, int ascq)
858 {
859 	scsi_build_sense(scmd, 1, ILLEGAL_REQUEST, 0x10, ascq);
860 	set_host_byte(scmd, DID_SOFT_ERROR);
861 }
862 
863 void zfcp_scsi_shost_update_config_data(
864 	struct zfcp_adapter *const adapter,
865 	const struct fsf_qtcb_bottom_config *const bottom,
866 	const bool bottom_incomplete)
867 {
868 	struct Scsi_Host *const shost = adapter->scsi_host;
869 	const struct fc_els_flogi *nsp, *plogi;
870 
871 	if (shost == NULL)
872 		return;
873 
874 	snprintf(fc_host_firmware_version(shost), FC_VERSION_STRING_SIZE,
875 		 "0x%08x", bottom->lic_version);
876 
877 	if (adapter->adapter_features & FSF_FEATURE_HBAAPI_MANAGEMENT) {
878 		snprintf(fc_host_hardware_version(shost),
879 			 FC_VERSION_STRING_SIZE,
880 			 "0x%08x", bottom->hardware_version);
881 		memcpy(fc_host_serial_number(shost), bottom->serial_number,
882 		       min(FC_SERIAL_NUMBER_SIZE, 17));
883 		EBCASC(fc_host_serial_number(shost),
884 		       min(FC_SERIAL_NUMBER_SIZE, 17));
885 	}
886 
887 	/* adjust pointers for missing command code */
888 	nsp = (struct fc_els_flogi *) ((u8 *)&bottom->nport_serv_param
889 					- sizeof(u32));
890 	plogi = (struct fc_els_flogi *) ((u8 *)&bottom->plogi_payload
891 					- sizeof(u32));
892 
893 	snprintf(fc_host_manufacturer(shost), FC_SERIAL_NUMBER_SIZE, "%s",
894 		 "IBM");
895 	fc_host_port_name(shost) = be64_to_cpu(nsp->fl_wwpn);
896 	fc_host_node_name(shost) = be64_to_cpu(nsp->fl_wwnn);
897 	fc_host_supported_classes(shost) = FC_COS_CLASS2 | FC_COS_CLASS3;
898 
899 	zfcp_scsi_set_prot(adapter);
900 
901 	/* do not evaluate invalid fields */
902 	if (bottom_incomplete)
903 		return;
904 
905 	fc_host_port_id(shost) = ntoh24(bottom->s_id);
906 	fc_host_speed(shost) =
907 		zfcp_fsf_convert_portspeed(bottom->fc_link_speed);
908 
909 	snprintf(fc_host_model(shost), FC_SYMBOLIC_NAME_SIZE, "0x%04x",
910 		 bottom->adapter_type);
911 
912 	switch (bottom->fc_topology) {
913 	case FSF_TOPO_P2P:
914 		fc_host_port_type(shost) = FC_PORTTYPE_PTP;
915 		fc_host_fabric_name(shost) = 0;
916 		break;
917 	case FSF_TOPO_FABRIC:
918 		fc_host_fabric_name(shost) = be64_to_cpu(plogi->fl_wwnn);
919 		if (bottom->connection_features & FSF_FEATURE_NPIV_MODE)
920 			fc_host_port_type(shost) = FC_PORTTYPE_NPIV;
921 		else
922 			fc_host_port_type(shost) = FC_PORTTYPE_NPORT;
923 		break;
924 	case FSF_TOPO_AL:
925 		fc_host_port_type(shost) = FC_PORTTYPE_NLPORT;
926 		fallthrough;
927 	default:
928 		fc_host_fabric_name(shost) = 0;
929 		break;
930 	}
931 }
932 
933 void zfcp_scsi_shost_update_port_data(
934 	struct zfcp_adapter *const adapter,
935 	const struct fsf_qtcb_bottom_port *const bottom)
936 {
937 	struct Scsi_Host *const shost = adapter->scsi_host;
938 
939 	if (shost == NULL)
940 		return;
941 
942 	fc_host_permanent_port_name(shost) = bottom->wwpn;
943 	fc_host_maxframe_size(shost) = bottom->maximum_frame_size;
944 	fc_host_supported_speeds(shost) =
945 		zfcp_fsf_convert_portspeed(bottom->supported_speed);
946 	memcpy(fc_host_supported_fc4s(shost), bottom->supported_fc4_types,
947 	       FC_FC4_LIST_SIZE);
948 	memcpy(fc_host_active_fc4s(shost), bottom->active_fc4_types,
949 	       FC_FC4_LIST_SIZE);
950 }
951 
952 struct fc_function_template zfcp_transport_functions = {
953 	.show_starget_port_id = 1,
954 	.show_starget_port_name = 1,
955 	.show_starget_node_name = 1,
956 	.show_rport_supported_classes = 1,
957 	.show_rport_maxframe_size = 1,
958 	.show_rport_dev_loss_tmo = 1,
959 	.show_host_node_name = 1,
960 	.show_host_port_name = 1,
961 	.show_host_permanent_port_name = 1,
962 	.show_host_supported_classes = 1,
963 	.show_host_supported_fc4s = 1,
964 	.show_host_supported_speeds = 1,
965 	.show_host_maxframe_size = 1,
966 	.show_host_serial_number = 1,
967 	.show_host_manufacturer = 1,
968 	.show_host_model = 1,
969 	.show_host_hardware_version = 1,
970 	.show_host_firmware_version = 1,
971 	.get_fc_host_stats = zfcp_scsi_get_fc_host_stats,
972 	.reset_fc_host_stats = zfcp_scsi_reset_fc_host_stats,
973 	.set_rport_dev_loss_tmo = zfcp_scsi_set_rport_dev_loss_tmo,
974 	.get_host_port_state = zfcp_scsi_get_host_port_state,
975 	.terminate_rport_io = zfcp_scsi_terminate_rport_io,
976 	.show_host_port_state = 1,
977 	.show_host_active_fc4s = 1,
978 	.bsg_request = zfcp_fc_exec_bsg_job,
979 	.bsg_timeout = zfcp_fc_timeout_bsg_job,
980 	/* no functions registered for following dynamic attributes but
981 	   directly set by LLDD */
982 	.show_host_port_type = 1,
983 	.show_host_symbolic_name = 1,
984 	.show_host_speed = 1,
985 	.show_host_port_id = 1,
986 	.show_host_fabric_name = 1,
987 	.dd_bsg_size = sizeof(struct zfcp_fsf_ct_els),
988 };
989