1// SPDX-License-Identifier: GPL-2.0
2/*
3 * zfcp device driver
4 *
5 * Registration and callback for the s390 common I/O layer.
6 *
7 * Copyright IBM Corp. 2002, 2010
8 */
9
10#define KMSG_COMPONENT "zfcp"
11#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
12
13#include <linux/module.h>
14#include "zfcp_ext.h"
15#include "zfcp_reqlist.h"
16
17#define ZFCP_MODEL_PRIV 0x4
18
19static DEFINE_SPINLOCK(zfcp_ccw_adapter_ref_lock);
20
21struct zfcp_adapter *zfcp_ccw_adapter_by_cdev(struct ccw_device *cdev)
22{
23 struct zfcp_adapter *adapter;
24 unsigned long flags;
25
26 spin_lock_irqsave(&zfcp_ccw_adapter_ref_lock, flags);
27 adapter = dev_get_drvdata(dev: &cdev->dev);
28 if (adapter)
29 kref_get(kref: &adapter->ref);
30 spin_unlock_irqrestore(lock: &zfcp_ccw_adapter_ref_lock, flags);
31 return adapter;
32}
33
34void zfcp_ccw_adapter_put(struct zfcp_adapter *adapter)
35{
36 unsigned long flags;
37
38 spin_lock_irqsave(&zfcp_ccw_adapter_ref_lock, flags);
39 kref_put(kref: &adapter->ref, release: zfcp_adapter_release);
40 spin_unlock_irqrestore(lock: &zfcp_ccw_adapter_ref_lock, flags);
41}
42
43/**
44 * zfcp_ccw_activate - activate adapter and wait for it to finish
45 * @cdev: pointer to belonging ccw device
46 * @clear: Status flags to clear.
47 * @tag: s390dbf trace record tag
48 */
49static int zfcp_ccw_activate(struct ccw_device *cdev, int clear, char *tag)
50{
51 struct zfcp_adapter *adapter = zfcp_ccw_adapter_by_cdev(cdev);
52
53 if (!adapter)
54 return 0;
55
56 zfcp_erp_clear_adapter_status(adapter, clear);
57 zfcp_erp_set_adapter_status(adapter, ZFCP_STATUS_COMMON_RUNNING);
58 zfcp_erp_adapter_reopen(adapter, ZFCP_STATUS_COMMON_ERP_FAILED,
59 tag);
60
61 /*
62 * We want to scan ports here, with some random backoff and without
63 * rate limit. Recovery has already scheduled a port scan for us,
64 * but with both random delay and rate limit. Nevertheless we get
65 * what we want here by flushing the scheduled work after sleeping
66 * an equivalent random time.
67 * Let the port scan random delay elapse first. If recovery finishes
68 * up to that point in time, that would be perfect for both recovery
69 * and port scan. If not, i.e. recovery takes ages, there was no
70 * point in waiting a random delay on top of the time consumed by
71 * recovery.
72 */
73 msleep(msecs: zfcp_fc_port_scan_backoff());
74 zfcp_erp_wait(adapter);
75 flush_delayed_work(dwork: &adapter->scan_work);
76
77 zfcp_ccw_adapter_put(adapter);
78
79 return 0;
80}
81
82static struct ccw_device_id zfcp_ccw_device_id[] = {
83 { CCW_DEVICE_DEVTYPE(0x1731, 0x3, 0x1732, 0x3) },
84 { CCW_DEVICE_DEVTYPE(0x1731, 0x3, 0x1732, ZFCP_MODEL_PRIV) },
85 {},
86};
87MODULE_DEVICE_TABLE(ccw, zfcp_ccw_device_id);
88
89/**
90 * zfcp_ccw_probe - probe function of zfcp driver
91 * @cdev: pointer to belonging ccw device
92 *
93 * This function gets called by the common i/o layer for each FCP
94 * device found on the current system. This is only a stub to make cio
95 * work: To only allocate adapter resources for devices actually used,
96 * the allocation is deferred to the first call to ccw_set_online.
97 */
98static int zfcp_ccw_probe(struct ccw_device *cdev)
99{
100 return 0;
101}
102
103/**
104 * zfcp_ccw_remove - remove function of zfcp driver
105 * @cdev: pointer to belonging ccw device
106 *
107 * This function gets called by the common i/o layer and removes an adapter
108 * from the system. Task of this function is to get rid of all units and
109 * ports that belong to this adapter. And in addition all resources of this
110 * adapter will be freed too.
111 */
112static void zfcp_ccw_remove(struct ccw_device *cdev)
113{
114 struct zfcp_adapter *adapter;
115 struct zfcp_port *port, *p;
116 struct zfcp_unit *unit, *u;
117 LIST_HEAD(unit_remove_lh);
118 LIST_HEAD(port_remove_lh);
119
120 ccw_device_set_offline(cdev);
121
122 adapter = zfcp_ccw_adapter_by_cdev(cdev);
123 if (!adapter)
124 return;
125
126 write_lock_irq(&adapter->port_list_lock);
127 list_for_each_entry(port, &adapter->port_list, list) {
128 write_lock(&port->unit_list_lock);
129 list_splice_init(list: &port->unit_list, head: &unit_remove_lh);
130 write_unlock(&port->unit_list_lock);
131 }
132 list_splice_init(list: &adapter->port_list, head: &port_remove_lh);
133 write_unlock_irq(&adapter->port_list_lock);
134 zfcp_ccw_adapter_put(adapter); /* put from zfcp_ccw_adapter_by_cdev */
135
136 list_for_each_entry_safe(unit, u, &unit_remove_lh, list)
137 device_unregister(dev: &unit->dev);
138
139 list_for_each_entry_safe(port, p, &port_remove_lh, list)
140 device_unregister(dev: &port->dev);
141
142 zfcp_adapter_unregister(adapter);
143}
144
145/**
146 * zfcp_ccw_set_online - set_online function of zfcp driver
147 * @cdev: pointer to belonging ccw device
148 *
149 * This function gets called by the common i/o layer and sets an
150 * adapter into state online. The first call will allocate all
151 * adapter resources that will be retained until the device is removed
152 * via zfcp_ccw_remove.
153 *
154 * Setting an fcp device online means that it will be registered with
155 * the SCSI stack, that the QDIO queues will be set up and that the
156 * adapter will be opened.
157 */
158static int zfcp_ccw_set_online(struct ccw_device *cdev)
159{
160 struct zfcp_adapter *adapter = zfcp_ccw_adapter_by_cdev(cdev);
161
162 if (!adapter) {
163 adapter = zfcp_adapter_enqueue(cdev);
164
165 if (IS_ERR(ptr: adapter)) {
166 dev_err(&cdev->dev,
167 "Setting up data structures for the "
168 "FCP adapter failed\n");
169 return PTR_ERR(ptr: adapter);
170 }
171 kref_get(kref: &adapter->ref);
172 }
173
174 /* initialize request counter */
175 BUG_ON(!zfcp_reqlist_isempty(adapter->req_list));
176 adapter->req_no = 0;
177
178 zfcp_ccw_activate(cdev, clear: 0, tag: "ccsonl1");
179
180 /*
181 * We want to scan ports here, always, with some random delay and
182 * without rate limit - basically what zfcp_ccw_activate() has
183 * achieved for us. Not quite! That port scan depended on
184 * !no_auto_port_rescan. So let's cover the no_auto_port_rescan
185 * case here to make sure a port scan is done unconditionally.
186 * Since zfcp_ccw_activate() has waited the desired random time,
187 * we can immediately schedule and flush a port scan for the
188 * remaining cases.
189 */
190 zfcp_fc_inverse_conditional_port_scan(adapter);
191 flush_delayed_work(dwork: &adapter->scan_work);
192 zfcp_ccw_adapter_put(adapter);
193 return 0;
194}
195
196/**
197 * zfcp_ccw_set_offline - set_offline function of zfcp driver
198 * @cdev: pointer to belonging ccw device
199 *
200 * This function gets called by the common i/o layer and sets an adapter
201 * into state offline.
202 */
203static int zfcp_ccw_set_offline(struct ccw_device *cdev)
204{
205 struct zfcp_adapter *adapter = zfcp_ccw_adapter_by_cdev(cdev);
206
207 if (!adapter)
208 return 0;
209
210 zfcp_erp_set_adapter_status(adapter, 0);
211 zfcp_erp_adapter_shutdown(adapter, 0, "ccsoff1");
212 zfcp_erp_wait(adapter);
213
214 zfcp_ccw_adapter_put(adapter);
215 return 0;
216}
217
218/**
219 * zfcp_ccw_notify - ccw notify function
220 * @cdev: pointer to belonging ccw device
221 * @event: indicates if adapter was detached or attached
222 *
223 * This function gets called by the common i/o layer if an adapter has gone
224 * or reappeared.
225 */
226static int zfcp_ccw_notify(struct ccw_device *cdev, int event)
227{
228 struct zfcp_adapter *adapter = zfcp_ccw_adapter_by_cdev(cdev);
229
230 if (!adapter)
231 return 1;
232
233 switch (event) {
234 case CIO_GONE:
235 dev_warn(&cdev->dev, "The FCP device has been detached\n");
236 zfcp_erp_adapter_shutdown(adapter, 0, "ccnoti1");
237 break;
238 case CIO_NO_PATH:
239 dev_warn(&cdev->dev,
240 "The CHPID for the FCP device is offline\n");
241 zfcp_erp_adapter_shutdown(adapter, 0, "ccnoti2");
242 break;
243 case CIO_OPER:
244 dev_info(&cdev->dev, "The FCP device is operational again\n");
245 zfcp_erp_set_adapter_status(adapter,
246 ZFCP_STATUS_COMMON_RUNNING);
247 zfcp_erp_adapter_reopen(adapter, ZFCP_STATUS_COMMON_ERP_FAILED,
248 "ccnoti4");
249 break;
250 case CIO_BOXED:
251 dev_warn(&cdev->dev, "The FCP device did not respond within "
252 "the specified time\n");
253 zfcp_erp_adapter_shutdown(adapter, 0, "ccnoti5");
254 break;
255 }
256
257 zfcp_ccw_adapter_put(adapter);
258 return 1;
259}
260
261/**
262 * zfcp_ccw_shutdown - handle shutdown from cio
263 * @cdev: device for adapter to shutdown.
264 */
265static void zfcp_ccw_shutdown(struct ccw_device *cdev)
266{
267 struct zfcp_adapter *adapter = zfcp_ccw_adapter_by_cdev(cdev);
268
269 if (!adapter)
270 return;
271
272 zfcp_erp_adapter_shutdown(adapter, 0, "ccshut1");
273 zfcp_erp_wait(adapter);
274 zfcp_erp_thread_kill(adapter);
275
276 zfcp_ccw_adapter_put(adapter);
277}
278
279struct ccw_driver zfcp_ccw_driver = {
280 .driver = {
281 .owner = THIS_MODULE,
282 .name = "zfcp",
283 },
284 .ids = zfcp_ccw_device_id,
285 .probe = zfcp_ccw_probe,
286 .remove = zfcp_ccw_remove,
287 .set_online = zfcp_ccw_set_online,
288 .set_offline = zfcp_ccw_set_offline,
289 .notify = zfcp_ccw_notify,
290 .shutdown = zfcp_ccw_shutdown,
291};
292

source code of linux/drivers/s390/scsi/zfcp_ccw.c