Commit | Line | Data |
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a6a8d9f8 CS |
1 | /* |
2 | * SCSI device handler infrastruture. | |
3 | * | |
4 | * This program is free software; you can redistribute it and/or modify it | |
5 | * under the terms of the GNU General Public License as published by the | |
6 | * Free Software Foundation; either version 2 of the License, or (at your | |
7 | * option) any later version. | |
8 | * | |
9 | * This program is distributed in the hope that it will be useful, but | |
10 | * WITHOUT ANY WARRANTY; without even the implied warranty of | |
11 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
12 | * General Public License for more details. | |
13 | * | |
14 | * You should have received a copy of the GNU General Public License along | |
15 | * with this program; if not, write to the Free Software Foundation, Inc., | |
16 | * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. | |
17 | * | |
18 | * Copyright IBM Corporation, 2007 | |
19 | * Authors: | |
20 | * Chandra Seetharaman <sekharan@us.ibm.com> | |
21 | * Mike Anderson <andmike@linux.vnet.ibm.com> | |
22 | */ | |
23 | ||
5a0e3ad6 | 24 | #include <linux/slab.h> |
acf3368f | 25 | #include <linux/module.h> |
a6a8d9f8 | 26 | #include <scsi/scsi_dh.h> |
daaa858b | 27 | #include "scsi_priv.h" |
a6a8d9f8 CS |
28 | |
29 | static DEFINE_SPINLOCK(list_lock); | |
30 | static LIST_HEAD(scsi_dh_list); | |
31 | ||
d95dbff2 CH |
32 | struct scsi_dh_blist { |
33 | const char *vendor; | |
34 | const char *model; | |
35 | const char *driver; | |
36 | }; | |
37 | ||
38 | static const struct scsi_dh_blist scsi_dh_blist[] = { | |
39 | {"DGC", "RAID", "clariion" }, | |
40 | {"DGC", "DISK", "clariion" }, | |
41 | {"DGC", "VRAID", "clariion" }, | |
42 | ||
43 | {"COMPAQ", "MSA1000 VOLUME", "hp_sw" }, | |
44 | {"COMPAQ", "HSV110", "hp_sw" }, | |
45 | {"HP", "HSV100", "hp_sw"}, | |
46 | {"DEC", "HSG80", "hp_sw"}, | |
47 | ||
48 | {"IBM", "1722", "rdac", }, | |
49 | {"IBM", "1724", "rdac", }, | |
50 | {"IBM", "1726", "rdac", }, | |
51 | {"IBM", "1742", "rdac", }, | |
52 | {"IBM", "1745", "rdac", }, | |
53 | {"IBM", "1746", "rdac", }, | |
54 | {"IBM", "1813", "rdac", }, | |
55 | {"IBM", "1814", "rdac", }, | |
56 | {"IBM", "1815", "rdac", }, | |
57 | {"IBM", "1818", "rdac", }, | |
58 | {"IBM", "3526", "rdac", }, | |
59 | {"SGI", "TP9", "rdac", }, | |
60 | {"SGI", "IS", "rdac", }, | |
61 | {"STK", "OPENstorage D280", "rdac", }, | |
62 | {"STK", "FLEXLINE 380", "rdac", }, | |
63 | {"SUN", "CSM", "rdac", }, | |
64 | {"SUN", "LCSM100", "rdac", }, | |
65 | {"SUN", "STK6580_6780", "rdac", }, | |
66 | {"SUN", "SUN_6180", "rdac", }, | |
67 | {"SUN", "ArrayStorage", "rdac", }, | |
68 | {"DELL", "MD3", "rdac", }, | |
69 | {"NETAPP", "INF-01-00", "rdac", }, | |
70 | {"LSI", "INF-01-00", "rdac", }, | |
71 | {"ENGENIO", "INF-01-00", "rdac", }, | |
72 | {NULL, NULL, NULL }, | |
73 | }; | |
74 | ||
75 | static const char * | |
76 | scsi_dh_find_driver(struct scsi_device *sdev) | |
77 | { | |
78 | const struct scsi_dh_blist *b; | |
79 | ||
80 | if (scsi_device_tpgs(sdev)) | |
81 | return "alua"; | |
82 | ||
83 | for (b = scsi_dh_blist; b->vendor; b++) { | |
84 | if (!strncmp(sdev->vendor, b->vendor, strlen(b->vendor)) && | |
85 | !strncmp(sdev->model, b->model, strlen(b->model))) { | |
86 | return b->driver; | |
87 | } | |
88 | } | |
89 | return NULL; | |
90 | } | |
91 | ||
92 | ||
566079c8 | 93 | static struct scsi_device_handler *__scsi_dh_lookup(const char *name) |
a6a8d9f8 CS |
94 | { |
95 | struct scsi_device_handler *tmp, *found = NULL; | |
96 | ||
97 | spin_lock(&list_lock); | |
98 | list_for_each_entry(tmp, &scsi_dh_list, list) { | |
765cbc6d | 99 | if (!strncmp(tmp->name, name, strlen(tmp->name))) { |
a6a8d9f8 CS |
100 | found = tmp; |
101 | break; | |
102 | } | |
103 | } | |
104 | spin_unlock(&list_lock); | |
105 | return found; | |
106 | } | |
107 | ||
566079c8 CH |
108 | static struct scsi_device_handler *scsi_dh_lookup(const char *name) |
109 | { | |
110 | struct scsi_device_handler *dh; | |
111 | ||
112 | dh = __scsi_dh_lookup(name); | |
113 | if (!dh) { | |
1378889c | 114 | request_module("scsi_dh_%s", name); |
566079c8 CH |
115 | dh = __scsi_dh_lookup(name); |
116 | } | |
117 | ||
118 | return dh; | |
119 | } | |
120 | ||
a6a8d9f8 | 121 | /* |
765cbc6d HR |
122 | * scsi_dh_handler_attach - Attach a device handler to a device |
123 | * @sdev - SCSI device the device handler should attach to | |
124 | * @scsi_dh - The device handler to attach | |
125 | */ | |
126 | static int scsi_dh_handler_attach(struct scsi_device *sdev, | |
127 | struct scsi_device_handler *scsi_dh) | |
128 | { | |
ee14c674 | 129 | int error; |
765cbc6d | 130 | |
1f12ffa5 CH |
131 | if (!try_module_get(scsi_dh->module)) |
132 | return -EINVAL; | |
27c888f0 | 133 | |
ee14c674 CH |
134 | error = scsi_dh->attach(sdev); |
135 | if (error) { | |
136 | sdev_printk(KERN_ERR, sdev, "%s: Attach failed (%d)\n", | |
137 | scsi_dh->name, error); | |
1f12ffa5 | 138 | module_put(scsi_dh->module); |
ee14c674 CH |
139 | } else |
140 | sdev->handler = scsi_dh; | |
1d520328 | 141 | |
ee14c674 | 142 | return error; |
765cbc6d HR |
143 | } |
144 | ||
1bab0de0 CH |
145 | /* |
146 | * scsi_dh_handler_detach - Detach a device handler from a device | |
147 | * @sdev - SCSI device the device handler should be detached from | |
148 | */ | |
149 | static void scsi_dh_handler_detach(struct scsi_device *sdev) | |
6c10db72 | 150 | { |
ee14c674 CH |
151 | sdev->handler->detach(sdev); |
152 | sdev_printk(KERN_NOTICE, sdev, "%s: Detached\n", sdev->handler->name); | |
153 | module_put(sdev->handler->module); | |
6c10db72 CS |
154 | } |
155 | ||
086b91d0 | 156 | int scsi_dh_add_device(struct scsi_device *sdev) |
4c05ae52 | 157 | { |
d95dbff2 CH |
158 | struct scsi_device_handler *devinfo = NULL; |
159 | const char *drv; | |
41f95dd2 | 160 | int err = 0; |
4c05ae52 | 161 | |
d95dbff2 CH |
162 | drv = scsi_dh_find_driver(sdev); |
163 | if (drv) | |
d6a32b98 | 164 | devinfo = __scsi_dh_lookup(drv); |
086b91d0 CH |
165 | if (devinfo) |
166 | err = scsi_dh_handler_attach(sdev, devinfo); | |
765cbc6d | 167 | return err; |
a6a8d9f8 | 168 | } |
a6a8d9f8 | 169 | |
23695e41 | 170 | void scsi_dh_release_device(struct scsi_device *sdev) |
765cbc6d | 171 | { |
ee14c674 | 172 | if (sdev->handler) |
1bab0de0 | 173 | scsi_dh_handler_detach(sdev); |
23695e41 JN |
174 | } |
175 | ||
765cbc6d HR |
176 | /* |
177 | * scsi_register_device_handler - register a device handler personality | |
178 | * module. | |
179 | * @scsi_dh - device handler to be registered. | |
180 | * | |
181 | * Returns 0 on success, -EBUSY if handler already registered. | |
182 | */ | |
183 | int scsi_register_device_handler(struct scsi_device_handler *scsi_dh) | |
184 | { | |
566079c8 | 185 | if (__scsi_dh_lookup(scsi_dh->name)) |
765cbc6d HR |
186 | return -EBUSY; |
187 | ||
1f12ffa5 CH |
188 | if (!scsi_dh->attach || !scsi_dh->detach) |
189 | return -EINVAL; | |
190 | ||
765cbc6d HR |
191 | spin_lock(&list_lock); |
192 | list_add(&scsi_dh->list, &scsi_dh_list); | |
193 | spin_unlock(&list_lock); | |
940d7faa | 194 | |
765cbc6d HR |
195 | printk(KERN_INFO "%s: device handler registered\n", scsi_dh->name); |
196 | ||
197 | return SCSI_DH_OK; | |
198 | } | |
199 | EXPORT_SYMBOL_GPL(scsi_register_device_handler); | |
200 | ||
a6a8d9f8 CS |
201 | /* |
202 | * scsi_unregister_device_handler - register a device handler personality | |
203 | * module. | |
204 | * @scsi_dh - device handler to be unregistered. | |
205 | * | |
206 | * Returns 0 on success, -ENODEV if handler not registered. | |
207 | */ | |
208 | int scsi_unregister_device_handler(struct scsi_device_handler *scsi_dh) | |
209 | { | |
566079c8 | 210 | if (!__scsi_dh_lookup(scsi_dh->name)) |
765cbc6d | 211 | return -ENODEV; |
a6a8d9f8 | 212 | |
a6a8d9f8 CS |
213 | spin_lock(&list_lock); |
214 | list_del(&scsi_dh->list); | |
215 | spin_unlock(&list_lock); | |
765cbc6d | 216 | printk(KERN_INFO "%s: device handler unregistered\n", scsi_dh->name); |
a6a8d9f8 | 217 | |
765cbc6d | 218 | return SCSI_DH_OK; |
a6a8d9f8 CS |
219 | } |
220 | EXPORT_SYMBOL_GPL(scsi_unregister_device_handler); | |
221 | ||
e959ed9a CH |
222 | static struct scsi_device *get_sdev_from_queue(struct request_queue *q) |
223 | { | |
224 | struct scsi_device *sdev; | |
225 | unsigned long flags; | |
226 | ||
227 | spin_lock_irqsave(q->queue_lock, flags); | |
228 | sdev = q->queuedata; | |
229 | if (!sdev || !get_device(&sdev->sdev_gendev)) | |
230 | sdev = NULL; | |
231 | spin_unlock_irqrestore(q->queue_lock, flags); | |
232 | ||
233 | return sdev; | |
234 | } | |
235 | ||
a6a8d9f8 CS |
236 | /* |
237 | * scsi_dh_activate - activate the path associated with the scsi_device | |
238 | * corresponding to the given request queue. | |
3ae31f6a CS |
239 | * Returns immediately without waiting for activation to be completed. |
240 | * @q - Request queue that is associated with the scsi_device to be | |
241 | * activated. | |
242 | * @fn - Function to be called upon completion of the activation. | |
243 | * Function fn is called with data (below) and the error code. | |
244 | * Function fn may be called from the same calling context. So, | |
245 | * do not hold the lock in the caller which may be needed in fn. | |
246 | * @data - data passed to the function fn upon completion. | |
247 | * | |
a6a8d9f8 | 248 | */ |
3ae31f6a | 249 | int scsi_dh_activate(struct request_queue *q, activate_complete fn, void *data) |
a6a8d9f8 | 250 | { |
a6a8d9f8 | 251 | struct scsi_device *sdev; |
e959ed9a | 252 | int err = SCSI_DH_NOSYS; |
a6a8d9f8 | 253 | |
e959ed9a | 254 | sdev = get_sdev_from_queue(q); |
a18a920c | 255 | if (!sdev) { |
a18a920c MB |
256 | if (fn) |
257 | fn(data, err); | |
258 | return err; | |
259 | } | |
260 | ||
e959ed9a CH |
261 | if (!sdev->handler) |
262 | goto out_fn; | |
710105fd | 263 | err = SCSI_DH_NOTCONN; |
e959ed9a | 264 | if (sdev->sdev_state == SDEV_CANCEL || |
db422318 | 265 | sdev->sdev_state == SDEV_DEL) |
e959ed9a | 266 | goto out_fn; |
a6a8d9f8 | 267 | |
e959ed9a CH |
268 | err = SCSI_DH_DEV_OFFLINED; |
269 | if (sdev->sdev_state == SDEV_OFFLINE) | |
270 | goto out_fn; | |
a6a8d9f8 | 271 | |
ee14c674 CH |
272 | if (sdev->handler->activate) |
273 | err = sdev->handler->activate(sdev, fn, data); | |
e959ed9a CH |
274 | |
275 | out_put_device: | |
276 | put_device(&sdev->sdev_gendev); | |
a6a8d9f8 | 277 | return err; |
e959ed9a CH |
278 | |
279 | out_fn: | |
280 | if (fn) | |
281 | fn(data, err); | |
282 | goto out_put_device; | |
a6a8d9f8 CS |
283 | } |
284 | EXPORT_SYMBOL_GPL(scsi_dh_activate); | |
285 | ||
18ee70c9 CS |
286 | /* |
287 | * scsi_dh_set_params - set the parameters for the device as per the | |
288 | * string specified in params. | |
289 | * @q - Request queue that is associated with the scsi_device for | |
290 | * which the parameters to be set. | |
291 | * @params - parameters in the following format | |
292 | * "no_of_params\0param1\0param2\0param3\0...\0" | |
293 | * for example, string for 2 parameters with value 10 and 21 | |
294 | * is specified as "2\010\021\0". | |
295 | */ | |
296 | int scsi_dh_set_params(struct request_queue *q, const char *params) | |
297 | { | |
18ee70c9 | 298 | struct scsi_device *sdev; |
e959ed9a | 299 | int err = -SCSI_DH_NOSYS; |
18ee70c9 | 300 | |
e959ed9a CH |
301 | sdev = get_sdev_from_queue(q); |
302 | if (!sdev) | |
18ee70c9 | 303 | return err; |
e959ed9a CH |
304 | |
305 | if (sdev->handler && sdev->handler->set_params) | |
306 | err = sdev->handler->set_params(sdev, params); | |
18ee70c9 CS |
307 | put_device(&sdev->sdev_gendev); |
308 | return err; | |
309 | } | |
310 | EXPORT_SYMBOL_GPL(scsi_dh_set_params); | |
311 | ||
ae11b1b3 | 312 | /* |
2a9ab40f | 313 | * scsi_dh_attach - Attach device handler |
7e8a74b1 MS |
314 | * @q - Request queue that is associated with the scsi_device |
315 | * the handler should be attached to | |
ae11b1b3 HR |
316 | * @name - name of the handler to attach |
317 | */ | |
318 | int scsi_dh_attach(struct request_queue *q, const char *name) | |
319 | { | |
ae11b1b3 HR |
320 | struct scsi_device *sdev; |
321 | struct scsi_device_handler *scsi_dh; | |
322 | int err = 0; | |
323 | ||
e959ed9a CH |
324 | sdev = get_sdev_from_queue(q); |
325 | if (!sdev) | |
326 | return -ENODEV; | |
ae11b1b3 | 327 | |
e959ed9a CH |
328 | scsi_dh = scsi_dh_lookup(name); |
329 | if (!scsi_dh) { | |
330 | err = -EINVAL; | |
331 | goto out_put_device; | |
332 | } | |
ae11b1b3 | 333 | |
ee14c674 CH |
334 | if (sdev->handler) { |
335 | if (sdev->handler != scsi_dh) | |
1bab0de0 CH |
336 | err = -EBUSY; |
337 | goto out_put_device; | |
ae11b1b3 | 338 | } |
1bab0de0 CH |
339 | |
340 | err = scsi_dh_handler_attach(sdev, scsi_dh); | |
341 | ||
342 | out_put_device: | |
ae11b1b3 | 343 | put_device(&sdev->sdev_gendev); |
1bab0de0 | 344 | return err; |
ae11b1b3 | 345 | } |
1bab0de0 | 346 | EXPORT_SYMBOL_GPL(scsi_dh_attach); |
ae11b1b3 | 347 | |
7e8a74b1 MS |
348 | /* |
349 | * scsi_dh_attached_handler_name - Get attached device handler's name | |
350 | * @q - Request queue that is associated with the scsi_device | |
351 | * that may have a device handler attached | |
352 | * @gfp - the GFP mask used in the kmalloc() call when allocating memory | |
353 | * | |
354 | * Returns name of attached handler, NULL if no handler is attached. | |
355 | * Caller must take care to free the returned string. | |
356 | */ | |
357 | const char *scsi_dh_attached_handler_name(struct request_queue *q, gfp_t gfp) | |
358 | { | |
7e8a74b1 MS |
359 | struct scsi_device *sdev; |
360 | const char *handler_name = NULL; | |
361 | ||
e959ed9a | 362 | sdev = get_sdev_from_queue(q); |
7e8a74b1 MS |
363 | if (!sdev) |
364 | return NULL; | |
365 | ||
ee14c674 CH |
366 | if (sdev->handler) |
367 | handler_name = kstrdup(sdev->handler->name, gfp); | |
7e8a74b1 MS |
368 | put_device(&sdev->sdev_gendev); |
369 | return handler_name; | |
370 | } | |
371 | EXPORT_SYMBOL_GPL(scsi_dh_attached_handler_name); |