xref: /openbmc/linux/drivers/s390/scsi/zfcp_ccw.c (revision 95e9fd10)
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 static int zfcp_ccw_activate(struct ccw_device *cdev)
43 
44 {
45 	struct zfcp_adapter *adapter = zfcp_ccw_adapter_by_cdev(cdev);
46 
47 	if (!adapter)
48 		return 0;
49 
50 	zfcp_erp_set_adapter_status(adapter, ZFCP_STATUS_COMMON_RUNNING);
51 	zfcp_erp_adapter_reopen(adapter, ZFCP_STATUS_COMMON_ERP_FAILED,
52 				"ccresu2");
53 	zfcp_erp_wait(adapter);
54 	flush_work(&adapter->scan_work);
55 
56 	zfcp_ccw_adapter_put(adapter);
57 
58 	return 0;
59 }
60 
61 static struct ccw_device_id zfcp_ccw_device_id[] = {
62 	{ CCW_DEVICE_DEVTYPE(0x1731, 0x3, 0x1732, 0x3) },
63 	{ CCW_DEVICE_DEVTYPE(0x1731, 0x3, 0x1732, ZFCP_MODEL_PRIV) },
64 	{},
65 };
66 MODULE_DEVICE_TABLE(ccw, zfcp_ccw_device_id);
67 
68 /**
69  * zfcp_ccw_priv_sch - check if subchannel is privileged
70  * @adapter: Adapter/Subchannel to check
71  */
72 int zfcp_ccw_priv_sch(struct zfcp_adapter *adapter)
73 {
74 	return adapter->ccw_device->id.dev_model == ZFCP_MODEL_PRIV;
75 }
76 
77 /**
78  * zfcp_ccw_probe - probe function of zfcp driver
79  * @cdev: pointer to belonging ccw device
80  *
81  * This function gets called by the common i/o layer for each FCP
82  * device found on the current system. This is only a stub to make cio
83  * work: To only allocate adapter resources for devices actually used,
84  * the allocation is deferred to the first call to ccw_set_online.
85  */
86 static int zfcp_ccw_probe(struct ccw_device *cdev)
87 {
88 	return 0;
89 }
90 
91 /**
92  * zfcp_ccw_remove - remove function of zfcp driver
93  * @cdev: pointer to belonging ccw device
94  *
95  * This function gets called by the common i/o layer and removes an adapter
96  * from the system. Task of this function is to get rid of all units and
97  * ports that belong to this adapter. And in addition all resources of this
98  * adapter will be freed too.
99  */
100 static void zfcp_ccw_remove(struct ccw_device *cdev)
101 {
102 	struct zfcp_adapter *adapter;
103 	struct zfcp_port *port, *p;
104 	struct zfcp_unit *unit, *u;
105 	LIST_HEAD(unit_remove_lh);
106 	LIST_HEAD(port_remove_lh);
107 
108 	ccw_device_set_offline(cdev);
109 
110 	adapter = zfcp_ccw_adapter_by_cdev(cdev);
111 	if (!adapter)
112 		return;
113 
114 	write_lock_irq(&adapter->port_list_lock);
115 	list_for_each_entry_safe(port, p, &adapter->port_list, list) {
116 		write_lock(&port->unit_list_lock);
117 		list_for_each_entry_safe(unit, u, &port->unit_list, list)
118 			list_move(&unit->list, &unit_remove_lh);
119 		write_unlock(&port->unit_list_lock);
120 		list_move(&port->list, &port_remove_lh);
121 	}
122 	write_unlock_irq(&adapter->port_list_lock);
123 	zfcp_ccw_adapter_put(adapter); /* put from zfcp_ccw_adapter_by_cdev */
124 
125 	list_for_each_entry_safe(unit, u, &unit_remove_lh, list)
126 		zfcp_device_unregister(&unit->dev, &zfcp_sysfs_unit_attrs);
127 
128 	list_for_each_entry_safe(port, p, &port_remove_lh, list)
129 		zfcp_device_unregister(&port->dev, &zfcp_sysfs_port_attrs);
130 
131 	zfcp_adapter_unregister(adapter);
132 }
133 
134 /**
135  * zfcp_ccw_set_online - set_online function of zfcp driver
136  * @cdev: pointer to belonging ccw device
137  *
138  * This function gets called by the common i/o layer and sets an
139  * adapter into state online.  The first call will allocate all
140  * adapter resources that will be retained until the device is removed
141  * via zfcp_ccw_remove.
142  *
143  * Setting an fcp device online means that it will be registered with
144  * the SCSI stack, that the QDIO queues will be set up and that the
145  * adapter will be opened.
146  */
147 static int zfcp_ccw_set_online(struct ccw_device *cdev)
148 {
149 	struct zfcp_adapter *adapter = zfcp_ccw_adapter_by_cdev(cdev);
150 
151 	if (!adapter) {
152 		adapter = zfcp_adapter_enqueue(cdev);
153 
154 		if (IS_ERR(adapter)) {
155 			dev_err(&cdev->dev,
156 				"Setting up data structures for the "
157 				"FCP adapter failed\n");
158 			return PTR_ERR(adapter);
159 		}
160 		kref_get(&adapter->ref);
161 	}
162 
163 	/* initialize request counter */
164 	BUG_ON(!zfcp_reqlist_isempty(adapter->req_list));
165 	adapter->req_no = 0;
166 
167 	zfcp_ccw_activate(cdev);
168 	zfcp_ccw_adapter_put(adapter);
169 	return 0;
170 }
171 
172 /**
173  * zfcp_ccw_set_offline - set_offline function of zfcp driver
174  * @cdev: pointer to belonging ccw device
175  *
176  * This function gets called by the common i/o layer and sets an adapter
177  * into state offline.
178  */
179 static int zfcp_ccw_set_offline(struct ccw_device *cdev)
180 {
181 	struct zfcp_adapter *adapter = zfcp_ccw_adapter_by_cdev(cdev);
182 
183 	if (!adapter)
184 		return 0;
185 
186 	zfcp_erp_adapter_shutdown(adapter, 0, "ccsoff1");
187 	zfcp_erp_wait(adapter);
188 
189 	zfcp_ccw_adapter_put(adapter);
190 	return 0;
191 }
192 
193 /**
194  * zfcp_ccw_notify - ccw notify function
195  * @cdev: pointer to belonging ccw device
196  * @event: indicates if adapter was detached or attached
197  *
198  * This function gets called by the common i/o layer if an adapter has gone
199  * or reappeared.
200  */
201 static int zfcp_ccw_notify(struct ccw_device *cdev, int event)
202 {
203 	struct zfcp_adapter *adapter = zfcp_ccw_adapter_by_cdev(cdev);
204 
205 	if (!adapter)
206 		return 1;
207 
208 	switch (event) {
209 	case CIO_GONE:
210 		dev_warn(&cdev->dev, "The FCP device has been detached\n");
211 		zfcp_erp_adapter_shutdown(adapter, 0, "ccnoti1");
212 		break;
213 	case CIO_NO_PATH:
214 		dev_warn(&cdev->dev,
215 			 "The CHPID for the FCP device is offline\n");
216 		zfcp_erp_adapter_shutdown(adapter, 0, "ccnoti2");
217 		break;
218 	case CIO_OPER:
219 		dev_info(&cdev->dev, "The FCP device is operational again\n");
220 		zfcp_erp_set_adapter_status(adapter,
221 					    ZFCP_STATUS_COMMON_RUNNING);
222 		zfcp_erp_adapter_reopen(adapter, ZFCP_STATUS_COMMON_ERP_FAILED,
223 					"ccnoti4");
224 		break;
225 	case CIO_BOXED:
226 		dev_warn(&cdev->dev, "The FCP device did not respond within "
227 				     "the specified time\n");
228 		zfcp_erp_adapter_shutdown(adapter, 0, "ccnoti5");
229 		break;
230 	}
231 
232 	zfcp_ccw_adapter_put(adapter);
233 	return 1;
234 }
235 
236 /**
237  * zfcp_ccw_shutdown - handle shutdown from cio
238  * @cdev: device for adapter to shutdown.
239  */
240 static void zfcp_ccw_shutdown(struct ccw_device *cdev)
241 {
242 	struct zfcp_adapter *adapter = zfcp_ccw_adapter_by_cdev(cdev);
243 
244 	if (!adapter)
245 		return;
246 
247 	zfcp_erp_adapter_shutdown(adapter, 0, "ccshut1");
248 	zfcp_erp_wait(adapter);
249 	zfcp_erp_thread_kill(adapter);
250 
251 	zfcp_ccw_adapter_put(adapter);
252 }
253 
254 struct ccw_driver zfcp_ccw_driver = {
255 	.driver = {
256 		.owner	= THIS_MODULE,
257 		.name	= "zfcp",
258 	},
259 	.ids         = zfcp_ccw_device_id,
260 	.probe       = zfcp_ccw_probe,
261 	.remove      = zfcp_ccw_remove,
262 	.set_online  = zfcp_ccw_set_online,
263 	.set_offline = zfcp_ccw_set_offline,
264 	.notify      = zfcp_ccw_notify,
265 	.shutdown    = zfcp_ccw_shutdown,
266 	.freeze      = zfcp_ccw_set_offline,
267 	.thaw	     = zfcp_ccw_activate,
268 	.restore     = zfcp_ccw_activate,
269 };
270