xref: /openbmc/linux/drivers/s390/scsi/zfcp_ccw.c (revision d0b73b48)
1 /*
2  * zfcp device driver
3  *
4  * Registration and callback for the s390 common I/O layer.
5  *
6  * Copyright IBM Corp. 2002, 2010
7  */
8 
9 #define KMSG_COMPONENT "zfcp"
10 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
11 
12 #include <linux/module.h>
13 #include "zfcp_ext.h"
14 #include "zfcp_reqlist.h"
15 
16 #define ZFCP_MODEL_PRIV 0x4
17 
18 static DEFINE_SPINLOCK(zfcp_ccw_adapter_ref_lock);
19 
20 struct zfcp_adapter *zfcp_ccw_adapter_by_cdev(struct ccw_device *cdev)
21 {
22 	struct zfcp_adapter *adapter;
23 	unsigned long flags;
24 
25 	spin_lock_irqsave(&zfcp_ccw_adapter_ref_lock, flags);
26 	adapter = dev_get_drvdata(&cdev->dev);
27 	if (adapter)
28 		kref_get(&adapter->ref);
29 	spin_unlock_irqrestore(&zfcp_ccw_adapter_ref_lock, flags);
30 	return adapter;
31 }
32 
33 void zfcp_ccw_adapter_put(struct zfcp_adapter *adapter)
34 {
35 	unsigned long flags;
36 
37 	spin_lock_irqsave(&zfcp_ccw_adapter_ref_lock, flags);
38 	kref_put(&adapter->ref, zfcp_adapter_release);
39 	spin_unlock_irqrestore(&zfcp_ccw_adapter_ref_lock, flags);
40 }
41 
42 /**
43  * zfcp_ccw_activate - activate adapter and wait for it to finish
44  * @cdev: pointer to belonging ccw device
45  * @clear: Status flags to clear.
46  * @tag: s390dbf trace record tag
47  */
48 static int zfcp_ccw_activate(struct ccw_device *cdev, int clear, char *tag)
49 {
50 	struct zfcp_adapter *adapter = zfcp_ccw_adapter_by_cdev(cdev);
51 
52 	if (!adapter)
53 		return 0;
54 
55 	zfcp_erp_clear_adapter_status(adapter, clear);
56 	zfcp_erp_set_adapter_status(adapter, ZFCP_STATUS_COMMON_RUNNING);
57 	zfcp_erp_adapter_reopen(adapter, ZFCP_STATUS_COMMON_ERP_FAILED,
58 				tag);
59 	zfcp_erp_wait(adapter);
60 	flush_work(&adapter->scan_work); /* ok to call even if nothing queued */
61 
62 	zfcp_ccw_adapter_put(adapter);
63 
64 	return 0;
65 }
66 
67 static struct ccw_device_id zfcp_ccw_device_id[] = {
68 	{ CCW_DEVICE_DEVTYPE(0x1731, 0x3, 0x1732, 0x3) },
69 	{ CCW_DEVICE_DEVTYPE(0x1731, 0x3, 0x1732, ZFCP_MODEL_PRIV) },
70 	{},
71 };
72 MODULE_DEVICE_TABLE(ccw, zfcp_ccw_device_id);
73 
74 /**
75  * zfcp_ccw_priv_sch - check if subchannel is privileged
76  * @adapter: Adapter/Subchannel to check
77  */
78 int zfcp_ccw_priv_sch(struct zfcp_adapter *adapter)
79 {
80 	return adapter->ccw_device->id.dev_model == ZFCP_MODEL_PRIV;
81 }
82 
83 /**
84  * zfcp_ccw_probe - probe function of zfcp driver
85  * @cdev: pointer to belonging ccw device
86  *
87  * This function gets called by the common i/o layer for each FCP
88  * device found on the current system. This is only a stub to make cio
89  * work: To only allocate adapter resources for devices actually used,
90  * the allocation is deferred to the first call to ccw_set_online.
91  */
92 static int zfcp_ccw_probe(struct ccw_device *cdev)
93 {
94 	return 0;
95 }
96 
97 /**
98  * zfcp_ccw_remove - remove function of zfcp driver
99  * @cdev: pointer to belonging ccw device
100  *
101  * This function gets called by the common i/o layer and removes an adapter
102  * from the system. Task of this function is to get rid of all units and
103  * ports that belong to this adapter. And in addition all resources of this
104  * adapter will be freed too.
105  */
106 static void zfcp_ccw_remove(struct ccw_device *cdev)
107 {
108 	struct zfcp_adapter *adapter;
109 	struct zfcp_port *port, *p;
110 	struct zfcp_unit *unit, *u;
111 	LIST_HEAD(unit_remove_lh);
112 	LIST_HEAD(port_remove_lh);
113 
114 	ccw_device_set_offline(cdev);
115 
116 	adapter = zfcp_ccw_adapter_by_cdev(cdev);
117 	if (!adapter)
118 		return;
119 
120 	write_lock_irq(&adapter->port_list_lock);
121 	list_for_each_entry_safe(port, p, &adapter->port_list, list) {
122 		write_lock(&port->unit_list_lock);
123 		list_for_each_entry_safe(unit, u, &port->unit_list, list)
124 			list_move(&unit->list, &unit_remove_lh);
125 		write_unlock(&port->unit_list_lock);
126 		list_move(&port->list, &port_remove_lh);
127 	}
128 	write_unlock_irq(&adapter->port_list_lock);
129 	zfcp_ccw_adapter_put(adapter); /* put from zfcp_ccw_adapter_by_cdev */
130 
131 	list_for_each_entry_safe(unit, u, &unit_remove_lh, list)
132 		zfcp_device_unregister(&unit->dev, &zfcp_sysfs_unit_attrs);
133 
134 	list_for_each_entry_safe(port, p, &port_remove_lh, list)
135 		zfcp_device_unregister(&port->dev, &zfcp_sysfs_port_attrs);
136 
137 	zfcp_adapter_unregister(adapter);
138 }
139 
140 /**
141  * zfcp_ccw_set_online - set_online function of zfcp driver
142  * @cdev: pointer to belonging ccw device
143  *
144  * This function gets called by the common i/o layer and sets an
145  * adapter into state online.  The first call will allocate all
146  * adapter resources that will be retained until the device is removed
147  * via zfcp_ccw_remove.
148  *
149  * Setting an fcp device online means that it will be registered with
150  * the SCSI stack, that the QDIO queues will be set up and that the
151  * adapter will be opened.
152  */
153 static int zfcp_ccw_set_online(struct ccw_device *cdev)
154 {
155 	struct zfcp_adapter *adapter = zfcp_ccw_adapter_by_cdev(cdev);
156 
157 	if (!adapter) {
158 		adapter = zfcp_adapter_enqueue(cdev);
159 
160 		if (IS_ERR(adapter)) {
161 			dev_err(&cdev->dev,
162 				"Setting up data structures for the "
163 				"FCP adapter failed\n");
164 			return PTR_ERR(adapter);
165 		}
166 		kref_get(&adapter->ref);
167 	}
168 
169 	/* initialize request counter */
170 	BUG_ON(!zfcp_reqlist_isempty(adapter->req_list));
171 	adapter->req_no = 0;
172 
173 	zfcp_ccw_activate(cdev, 0, "ccsonl1");
174 	/* scan for remote ports
175 	   either at the end of any successful adapter recovery
176 	   or only after the adapter recovery for setting a device online */
177 	zfcp_fc_inverse_conditional_port_scan(adapter);
178 	flush_work(&adapter->scan_work); /* ok to call even if nothing queued */
179 	zfcp_ccw_adapter_put(adapter);
180 	return 0;
181 }
182 
183 /**
184  * zfcp_ccw_offline_sync - shut down adapter and wait for it to finish
185  * @cdev: pointer to belonging ccw device
186  * @set: Status flags to set.
187  * @tag: s390dbf trace record tag
188  *
189  * This function gets called by the common i/o layer and sets an adapter
190  * into state offline.
191  */
192 static int zfcp_ccw_offline_sync(struct ccw_device *cdev, int set, char *tag)
193 {
194 	struct zfcp_adapter *adapter = zfcp_ccw_adapter_by_cdev(cdev);
195 
196 	if (!adapter)
197 		return 0;
198 
199 	zfcp_erp_set_adapter_status(adapter, set);
200 	zfcp_erp_adapter_shutdown(adapter, 0, tag);
201 	zfcp_erp_wait(adapter);
202 
203 	zfcp_ccw_adapter_put(adapter);
204 	return 0;
205 }
206 
207 /**
208  * zfcp_ccw_set_offline - set_offline function of zfcp driver
209  * @cdev: pointer to belonging ccw device
210  *
211  * This function gets called by the common i/o layer and sets an adapter
212  * into state offline.
213  */
214 static int zfcp_ccw_set_offline(struct ccw_device *cdev)
215 {
216 	return zfcp_ccw_offline_sync(cdev, 0, "ccsoff1");
217 }
218 
219 /**
220  * zfcp_ccw_notify - ccw notify function
221  * @cdev: pointer to belonging ccw device
222  * @event: indicates if adapter was detached or attached
223  *
224  * This function gets called by the common i/o layer if an adapter has gone
225  * or reappeared.
226  */
227 static int zfcp_ccw_notify(struct ccw_device *cdev, int event)
228 {
229 	struct zfcp_adapter *adapter = zfcp_ccw_adapter_by_cdev(cdev);
230 
231 	if (!adapter)
232 		return 1;
233 
234 	switch (event) {
235 	case CIO_GONE:
236 		if (atomic_read(&adapter->status) &
237 		    ZFCP_STATUS_ADAPTER_SUSPENDED) { /* notification ignore */
238 			zfcp_dbf_hba_basic("ccnigo1", adapter);
239 			break;
240 		}
241 		dev_warn(&cdev->dev, "The FCP device has been detached\n");
242 		zfcp_erp_adapter_shutdown(adapter, 0, "ccnoti1");
243 		break;
244 	case CIO_NO_PATH:
245 		dev_warn(&cdev->dev,
246 			 "The CHPID for the FCP device is offline\n");
247 		zfcp_erp_adapter_shutdown(adapter, 0, "ccnoti2");
248 		break;
249 	case CIO_OPER:
250 		if (atomic_read(&adapter->status) &
251 		    ZFCP_STATUS_ADAPTER_SUSPENDED) { /* notification ignore */
252 			zfcp_dbf_hba_basic("ccniop1", adapter);
253 			break;
254 		}
255 		dev_info(&cdev->dev, "The FCP device is operational again\n");
256 		zfcp_erp_set_adapter_status(adapter,
257 					    ZFCP_STATUS_COMMON_RUNNING);
258 		zfcp_erp_adapter_reopen(adapter, ZFCP_STATUS_COMMON_ERP_FAILED,
259 					"ccnoti4");
260 		break;
261 	case CIO_BOXED:
262 		dev_warn(&cdev->dev, "The FCP device did not respond within "
263 				     "the specified time\n");
264 		zfcp_erp_adapter_shutdown(adapter, 0, "ccnoti5");
265 		break;
266 	}
267 
268 	zfcp_ccw_adapter_put(adapter);
269 	return 1;
270 }
271 
272 /**
273  * zfcp_ccw_shutdown - handle shutdown from cio
274  * @cdev: device for adapter to shutdown.
275  */
276 static void zfcp_ccw_shutdown(struct ccw_device *cdev)
277 {
278 	struct zfcp_adapter *adapter = zfcp_ccw_adapter_by_cdev(cdev);
279 
280 	if (!adapter)
281 		return;
282 
283 	zfcp_erp_adapter_shutdown(adapter, 0, "ccshut1");
284 	zfcp_erp_wait(adapter);
285 	zfcp_erp_thread_kill(adapter);
286 
287 	zfcp_ccw_adapter_put(adapter);
288 }
289 
290 static int zfcp_ccw_suspend(struct ccw_device *cdev)
291 {
292 	zfcp_ccw_offline_sync(cdev, ZFCP_STATUS_ADAPTER_SUSPENDED, "ccsusp1");
293 	return 0;
294 }
295 
296 static int zfcp_ccw_thaw(struct ccw_device *cdev)
297 {
298 	/* trace records for thaw and final shutdown during suspend
299 	   can only be found in system dump until the end of suspend
300 	   but not after resume because it's based on the memory image
301 	   right after the very first suspend (freeze) callback */
302 	zfcp_ccw_activate(cdev, 0, "ccthaw1");
303 	return 0;
304 }
305 
306 static int zfcp_ccw_resume(struct ccw_device *cdev)
307 {
308 	zfcp_ccw_activate(cdev, ZFCP_STATUS_ADAPTER_SUSPENDED, "ccresu1");
309 	return 0;
310 }
311 
312 struct ccw_driver zfcp_ccw_driver = {
313 	.driver = {
314 		.owner	= THIS_MODULE,
315 		.name	= "zfcp",
316 	},
317 	.ids         = zfcp_ccw_device_id,
318 	.probe       = zfcp_ccw_probe,
319 	.remove      = zfcp_ccw_remove,
320 	.set_online  = zfcp_ccw_set_online,
321 	.set_offline = zfcp_ccw_set_offline,
322 	.notify      = zfcp_ccw_notify,
323 	.shutdown    = zfcp_ccw_shutdown,
324 	.freeze      = zfcp_ccw_suspend,
325 	.thaw	     = zfcp_ccw_thaw,
326 	.restore     = zfcp_ccw_resume,
327 };
328