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Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * dcssblk.c -- the S/390 block driver for dcss memory | |
3 | * | |
4 | * Authors: Carsten Otte, Stefan Weinhuber, Gerald Schaefer | |
5 | */ | |
6 | ||
7 | #include <linux/module.h> | |
8 | #include <linux/moduleparam.h> | |
9 | #include <linux/ctype.h> | |
10 | #include <linux/errno.h> | |
11 | #include <linux/init.h> | |
12 | #include <linux/slab.h> | |
13 | #include <linux/blkdev.h> | |
14 | #include <asm/extmem.h> | |
15 | #include <asm/io.h> | |
16 | #include <linux/completion.h> | |
17 | #include <linux/interrupt.h> | |
cfb1b555 | 18 | #include <asm/s390_rdev.h> |
1da177e4 LT |
19 | |
20 | //#define DCSSBLK_DEBUG /* Debug messages on/off */ | |
21 | #define DCSSBLK_NAME "dcssblk" | |
22 | #define DCSSBLK_MINORS_PER_DISK 1 | |
23 | #define DCSSBLK_PARM_LEN 400 | |
24 | ||
25 | #ifdef DCSSBLK_DEBUG | |
26 | #define PRINT_DEBUG(x...) printk(KERN_DEBUG DCSSBLK_NAME " debug: " x) | |
27 | #else | |
28 | #define PRINT_DEBUG(x...) do {} while (0) | |
29 | #endif | |
30 | #define PRINT_INFO(x...) printk(KERN_INFO DCSSBLK_NAME " info: " x) | |
31 | #define PRINT_WARN(x...) printk(KERN_WARNING DCSSBLK_NAME " warning: " x) | |
32 | #define PRINT_ERR(x...) printk(KERN_ERR DCSSBLK_NAME " error: " x) | |
33 | ||
46d74326 AV |
34 | static int dcssblk_open(struct block_device *bdev, fmode_t mode); |
35 | static int dcssblk_release(struct gendisk *disk, fmode_t mode); | |
1da177e4 | 36 | static int dcssblk_make_request(struct request_queue *q, struct bio *bio); |
420edbcc | 37 | static int dcssblk_direct_access(struct block_device *bdev, sector_t secnum, |
30afcb4b | 38 | void **kaddr, unsigned long *pfn); |
1da177e4 LT |
39 | |
40 | static char dcssblk_segments[DCSSBLK_PARM_LEN] = "\0"; | |
41 | ||
42 | static int dcssblk_major; | |
43 | static struct block_device_operations dcssblk_devops = { | |
420edbcc | 44 | .owner = THIS_MODULE, |
46d74326 AV |
45 | .open = dcssblk_open, |
46 | .release = dcssblk_release, | |
420edbcc | 47 | .direct_access = dcssblk_direct_access, |
1da177e4 LT |
48 | }; |
49 | ||
b2300b9e HY |
50 | struct dcssblk_dev_info { |
51 | struct list_head lh; | |
52 | struct device dev; | |
53 | char segment_name[BUS_ID_SIZE]; | |
54 | atomic_t use_count; | |
55 | struct gendisk *gd; | |
56 | unsigned long start; | |
57 | unsigned long end; | |
58 | int segment_type; | |
59 | unsigned char save_pending; | |
60 | unsigned char is_shared; | |
61 | struct request_queue *dcssblk_queue; | |
62 | int num_of_segments; | |
63 | struct list_head seg_list; | |
64 | }; | |
65 | ||
66 | struct segment_info { | |
67 | struct list_head lh; | |
68 | char segment_name[BUS_ID_SIZE]; | |
69 | unsigned long start; | |
70 | unsigned long end; | |
71 | int segment_type; | |
72 | }; | |
73 | ||
e404e274 | 74 | static ssize_t dcssblk_add_store(struct device * dev, struct device_attribute *attr, const char * buf, |
1da177e4 | 75 | size_t count); |
e404e274 | 76 | static ssize_t dcssblk_remove_store(struct device * dev, struct device_attribute *attr, const char * buf, |
1da177e4 | 77 | size_t count); |
e404e274 | 78 | static ssize_t dcssblk_save_store(struct device * dev, struct device_attribute *attr, const char * buf, |
1da177e4 | 79 | size_t count); |
e404e274 YI |
80 | static ssize_t dcssblk_save_show(struct device *dev, struct device_attribute *attr, char *buf); |
81 | static ssize_t dcssblk_shared_store(struct device * dev, struct device_attribute *attr, const char * buf, | |
1da177e4 | 82 | size_t count); |
e404e274 | 83 | static ssize_t dcssblk_shared_show(struct device *dev, struct device_attribute *attr, char *buf); |
b2300b9e HY |
84 | static ssize_t dcssblk_seglist_show(struct device *dev, |
85 | struct device_attribute *attr, | |
86 | char *buf); | |
1da177e4 LT |
87 | |
88 | static DEVICE_ATTR(add, S_IWUSR, NULL, dcssblk_add_store); | |
89 | static DEVICE_ATTR(remove, S_IWUSR, NULL, dcssblk_remove_store); | |
b2300b9e | 90 | static DEVICE_ATTR(save, S_IWUSR | S_IRUSR, dcssblk_save_show, |
1da177e4 | 91 | dcssblk_save_store); |
b2300b9e | 92 | static DEVICE_ATTR(shared, S_IWUSR | S_IRUSR, dcssblk_shared_show, |
1da177e4 | 93 | dcssblk_shared_store); |
b2300b9e | 94 | static DEVICE_ATTR(seglist, S_IRUSR, dcssblk_seglist_show, NULL); |
1da177e4 LT |
95 | |
96 | static struct device *dcssblk_root_dev; | |
97 | ||
c11ca97e | 98 | static LIST_HEAD(dcssblk_devices); |
1da177e4 LT |
99 | static struct rw_semaphore dcssblk_devices_sem; |
100 | ||
101 | /* | |
102 | * release function for segment device. | |
103 | */ | |
104 | static void | |
105 | dcssblk_release_segment(struct device *dev) | |
106 | { | |
b2300b9e HY |
107 | struct dcssblk_dev_info *dev_info; |
108 | struct segment_info *entry, *temp; | |
109 | ||
110 | dev_info = container_of(dev, struct dcssblk_dev_info, dev); | |
111 | list_for_each_entry_safe(entry, temp, &dev_info->seg_list, lh) { | |
112 | list_del(&entry->lh); | |
113 | kfree(entry); | |
114 | } | |
115 | kfree(dev_info); | |
1da177e4 LT |
116 | module_put(THIS_MODULE); |
117 | } | |
118 | ||
119 | /* | |
120 | * get a minor number. needs to be called with | |
121 | * down_write(&dcssblk_devices_sem) and the | |
122 | * device needs to be enqueued before the semaphore is | |
123 | * freed. | |
124 | */ | |
4d284cac | 125 | static int |
1da177e4 LT |
126 | dcssblk_assign_free_minor(struct dcssblk_dev_info *dev_info) |
127 | { | |
128 | int minor, found; | |
129 | struct dcssblk_dev_info *entry; | |
130 | ||
131 | if (dev_info == NULL) | |
132 | return -EINVAL; | |
133 | for (minor = 0; minor < (1<<MINORBITS); minor++) { | |
134 | found = 0; | |
135 | // test if minor available | |
136 | list_for_each_entry(entry, &dcssblk_devices, lh) | |
f331c029 | 137 | if (minor == MINOR(disk_devt(entry->gd))) |
1da177e4 LT |
138 | found++; |
139 | if (!found) break; // got unused minor | |
140 | } | |
141 | if (found) | |
142 | return -EBUSY; | |
143 | dev_info->gd->first_minor = minor; | |
144 | return 0; | |
145 | } | |
146 | ||
147 | /* | |
148 | * get the struct dcssblk_dev_info from dcssblk_devices | |
149 | * for the given name. | |
150 | * down_read(&dcssblk_devices_sem) must be held. | |
151 | */ | |
152 | static struct dcssblk_dev_info * | |
153 | dcssblk_get_device_by_name(char *name) | |
154 | { | |
155 | struct dcssblk_dev_info *entry; | |
156 | ||
157 | list_for_each_entry(entry, &dcssblk_devices, lh) { | |
158 | if (!strcmp(name, entry->segment_name)) { | |
159 | return entry; | |
160 | } | |
161 | } | |
162 | return NULL; | |
163 | } | |
164 | ||
b2300b9e HY |
165 | /* |
166 | * get the struct segment_info from seg_list | |
167 | * for the given name. | |
168 | * down_read(&dcssblk_devices_sem) must be held. | |
169 | */ | |
170 | static struct segment_info * | |
171 | dcssblk_get_segment_by_name(char *name) | |
172 | { | |
173 | struct dcssblk_dev_info *dev_info; | |
174 | struct segment_info *entry; | |
175 | ||
176 | list_for_each_entry(dev_info, &dcssblk_devices, lh) { | |
177 | list_for_each_entry(entry, &dev_info->seg_list, lh) { | |
178 | if (!strcmp(name, entry->segment_name)) | |
179 | return entry; | |
180 | } | |
181 | } | |
182 | return NULL; | |
183 | } | |
184 | ||
185 | /* | |
186 | * get the highest address of the multi-segment block. | |
187 | */ | |
188 | static unsigned long | |
189 | dcssblk_find_highest_addr(struct dcssblk_dev_info *dev_info) | |
190 | { | |
191 | unsigned long highest_addr; | |
192 | struct segment_info *entry; | |
193 | ||
194 | highest_addr = 0; | |
195 | list_for_each_entry(entry, &dev_info->seg_list, lh) { | |
196 | if (highest_addr < entry->end) | |
197 | highest_addr = entry->end; | |
198 | } | |
199 | return highest_addr; | |
200 | } | |
201 | ||
202 | /* | |
203 | * get the lowest address of the multi-segment block. | |
204 | */ | |
205 | static unsigned long | |
206 | dcssblk_find_lowest_addr(struct dcssblk_dev_info *dev_info) | |
207 | { | |
208 | int set_first; | |
209 | unsigned long lowest_addr; | |
210 | struct segment_info *entry; | |
211 | ||
212 | set_first = 0; | |
213 | lowest_addr = 0; | |
214 | list_for_each_entry(entry, &dev_info->seg_list, lh) { | |
215 | if (set_first == 0) { | |
216 | lowest_addr = entry->start; | |
217 | set_first = 1; | |
218 | } else { | |
219 | if (lowest_addr > entry->start) | |
220 | lowest_addr = entry->start; | |
221 | } | |
222 | } | |
223 | return lowest_addr; | |
224 | } | |
225 | ||
226 | /* | |
227 | * Check continuity of segments. | |
228 | */ | |
229 | static int | |
230 | dcssblk_is_continuous(struct dcssblk_dev_info *dev_info) | |
231 | { | |
232 | int i, j, rc; | |
233 | struct segment_info *sort_list, *entry, temp; | |
234 | ||
235 | if (dev_info->num_of_segments <= 1) | |
236 | return 0; | |
237 | ||
238 | sort_list = kzalloc( | |
239 | sizeof(struct segment_info) * dev_info->num_of_segments, | |
240 | GFP_KERNEL); | |
241 | if (sort_list == NULL) | |
242 | return -ENOMEM; | |
243 | i = 0; | |
244 | list_for_each_entry(entry, &dev_info->seg_list, lh) { | |
245 | memcpy(&sort_list[i], entry, sizeof(struct segment_info)); | |
246 | i++; | |
247 | } | |
248 | ||
249 | /* sort segments */ | |
250 | for (i = 0; i < dev_info->num_of_segments; i++) | |
251 | for (j = 0; j < dev_info->num_of_segments; j++) | |
252 | if (sort_list[j].start > sort_list[i].start) { | |
253 | memcpy(&temp, &sort_list[i], | |
254 | sizeof(struct segment_info)); | |
255 | memcpy(&sort_list[i], &sort_list[j], | |
256 | sizeof(struct segment_info)); | |
257 | memcpy(&sort_list[j], &temp, | |
258 | sizeof(struct segment_info)); | |
259 | } | |
260 | ||
261 | /* check continuity */ | |
262 | for (i = 0; i < dev_info->num_of_segments - 1; i++) { | |
263 | if ((sort_list[i].end + 1) != sort_list[i+1].start) { | |
264 | PRINT_ERR("Segment %s is not contiguous with " | |
265 | "segment %s\n", | |
266 | sort_list[i].segment_name, | |
267 | sort_list[i+1].segment_name); | |
268 | rc = -EINVAL; | |
269 | goto out; | |
270 | } | |
271 | /* EN and EW are allowed in a block device */ | |
272 | if (sort_list[i].segment_type != sort_list[i+1].segment_type) { | |
273 | if (!(sort_list[i].segment_type & SEGMENT_EXCLUSIVE) || | |
274 | (sort_list[i].segment_type == SEG_TYPE_ER) || | |
275 | !(sort_list[i+1].segment_type & | |
276 | SEGMENT_EXCLUSIVE) || | |
277 | (sort_list[i+1].segment_type == SEG_TYPE_ER)) { | |
278 | PRINT_ERR("Segment %s has different type from " | |
279 | "segment %s\n", | |
280 | sort_list[i].segment_name, | |
281 | sort_list[i+1].segment_name); | |
282 | rc = -EINVAL; | |
283 | goto out; | |
284 | } | |
285 | } | |
286 | } | |
287 | rc = 0; | |
288 | out: | |
289 | kfree(sort_list); | |
290 | return rc; | |
291 | } | |
292 | ||
293 | /* | |
294 | * Load a segment | |
295 | */ | |
296 | static int | |
297 | dcssblk_load_segment(char *name, struct segment_info **seg_info) | |
298 | { | |
299 | int rc; | |
300 | ||
301 | /* already loaded? */ | |
302 | down_read(&dcssblk_devices_sem); | |
303 | *seg_info = dcssblk_get_segment_by_name(name); | |
304 | up_read(&dcssblk_devices_sem); | |
305 | if (*seg_info != NULL) | |
306 | return -EEXIST; | |
307 | ||
308 | /* get a struct segment_info */ | |
309 | *seg_info = kzalloc(sizeof(struct segment_info), GFP_KERNEL); | |
310 | if (*seg_info == NULL) | |
311 | return -ENOMEM; | |
312 | ||
313 | strcpy((*seg_info)->segment_name, name); | |
314 | ||
315 | /* load the segment */ | |
316 | rc = segment_load(name, SEGMENT_SHARED, | |
317 | &(*seg_info)->start, &(*seg_info)->end); | |
318 | if (rc < 0) { | |
319 | segment_warning(rc, (*seg_info)->segment_name); | |
320 | kfree(*seg_info); | |
321 | } else { | |
322 | INIT_LIST_HEAD(&(*seg_info)->lh); | |
323 | (*seg_info)->segment_type = rc; | |
324 | } | |
325 | return rc; | |
326 | } | |
327 | ||
931bb68b GS |
328 | static void dcssblk_unregister_callback(struct device *dev) |
329 | { | |
330 | device_unregister(dev); | |
331 | put_device(dev); | |
332 | } | |
333 | ||
1da177e4 LT |
334 | /* |
335 | * device attribute for switching shared/nonshared (exclusive) | |
336 | * operation (show + store) | |
337 | */ | |
338 | static ssize_t | |
e404e274 | 339 | dcssblk_shared_show(struct device *dev, struct device_attribute *attr, char *buf) |
1da177e4 LT |
340 | { |
341 | struct dcssblk_dev_info *dev_info; | |
342 | ||
343 | dev_info = container_of(dev, struct dcssblk_dev_info, dev); | |
344 | return sprintf(buf, dev_info->is_shared ? "1\n" : "0\n"); | |
345 | } | |
346 | ||
347 | static ssize_t | |
e404e274 | 348 | dcssblk_shared_store(struct device *dev, struct device_attribute *attr, const char *inbuf, size_t count) |
1da177e4 LT |
349 | { |
350 | struct dcssblk_dev_info *dev_info; | |
b2300b9e | 351 | struct segment_info *entry, *temp; |
1da177e4 LT |
352 | int rc; |
353 | ||
ded77fb4 | 354 | if ((count > 1) && (inbuf[1] != '\n') && (inbuf[1] != '\0')) |
1da177e4 | 355 | return -EINVAL; |
1da177e4 LT |
356 | down_write(&dcssblk_devices_sem); |
357 | dev_info = container_of(dev, struct dcssblk_dev_info, dev); | |
358 | if (atomic_read(&dev_info->use_count)) { | |
1da177e4 LT |
359 | rc = -EBUSY; |
360 | goto out; | |
361 | } | |
362 | if (inbuf[0] == '1') { | |
b2300b9e HY |
363 | /* reload segments in shared mode */ |
364 | list_for_each_entry(entry, &dev_info->seg_list, lh) { | |
365 | rc = segment_modify_shared(entry->segment_name, | |
366 | SEGMENT_SHARED); | |
367 | if (rc < 0) { | |
368 | BUG_ON(rc == -EINVAL); | |
369 | if (rc != -EAGAIN) | |
370 | goto removeseg; | |
1da177e4 LT |
371 | } |
372 | } | |
b2300b9e HY |
373 | dev_info->is_shared = 1; |
374 | switch (dev_info->segment_type) { | |
375 | case SEG_TYPE_SR: | |
376 | case SEG_TYPE_ER: | |
377 | case SEG_TYPE_SC: | |
378 | set_disk_ro(dev_info->gd, 1); | |
379 | } | |
1da177e4 | 380 | } else if (inbuf[0] == '0') { |
b2300b9e | 381 | /* reload segments in exclusive mode */ |
1da177e4 LT |
382 | if (dev_info->segment_type == SEG_TYPE_SC) { |
383 | PRINT_ERR("Segment type SC (%s) cannot be loaded in " | |
b2300b9e | 384 | "non-shared mode\n", dev_info->segment_name); |
1da177e4 LT |
385 | rc = -EINVAL; |
386 | goto out; | |
387 | } | |
b2300b9e HY |
388 | list_for_each_entry(entry, &dev_info->seg_list, lh) { |
389 | rc = segment_modify_shared(entry->segment_name, | |
390 | SEGMENT_EXCLUSIVE); | |
391 | if (rc < 0) { | |
392 | BUG_ON(rc == -EINVAL); | |
393 | if (rc != -EAGAIN) | |
394 | goto removeseg; | |
395 | } | |
1da177e4 | 396 | } |
b2300b9e HY |
397 | dev_info->is_shared = 0; |
398 | set_disk_ro(dev_info->gd, 0); | |
1da177e4 | 399 | } else { |
1da177e4 LT |
400 | rc = -EINVAL; |
401 | goto out; | |
402 | } | |
403 | rc = count; | |
404 | goto out; | |
405 | ||
406 | removeseg: | |
b2300b9e HY |
407 | PRINT_ERR("Could not reload segment(s) of the device %s, removing " |
408 | "segment(s) now!\n", | |
409 | dev_info->segment_name); | |
410 | temp = entry; | |
411 | list_for_each_entry(entry, &dev_info->seg_list, lh) { | |
412 | if (entry != temp) | |
413 | segment_unload(entry->segment_name); | |
414 | } | |
1da177e4 LT |
415 | list_del(&dev_info->lh); |
416 | ||
417 | del_gendisk(dev_info->gd); | |
1312f40e | 418 | blk_cleanup_queue(dev_info->dcssblk_queue); |
1da177e4 LT |
419 | dev_info->gd->queue = NULL; |
420 | put_disk(dev_info->gd); | |
931bb68b | 421 | rc = device_schedule_callback(dev, dcssblk_unregister_callback); |
1da177e4 LT |
422 | out: |
423 | up_write(&dcssblk_devices_sem); | |
424 | return rc; | |
425 | } | |
426 | ||
427 | /* | |
428 | * device attribute for save operation on current copy | |
429 | * of the segment. If the segment is busy, saving will | |
430 | * become pending until it gets released, which can be | |
431 | * undone by storing a non-true value to this entry. | |
432 | * (show + store) | |
433 | */ | |
434 | static ssize_t | |
e404e274 | 435 | dcssblk_save_show(struct device *dev, struct device_attribute *attr, char *buf) |
1da177e4 LT |
436 | { |
437 | struct dcssblk_dev_info *dev_info; | |
438 | ||
439 | dev_info = container_of(dev, struct dcssblk_dev_info, dev); | |
440 | return sprintf(buf, dev_info->save_pending ? "1\n" : "0\n"); | |
441 | } | |
442 | ||
443 | static ssize_t | |
e404e274 | 444 | dcssblk_save_store(struct device *dev, struct device_attribute *attr, const char *inbuf, size_t count) |
1da177e4 LT |
445 | { |
446 | struct dcssblk_dev_info *dev_info; | |
b2300b9e | 447 | struct segment_info *entry; |
1da177e4 | 448 | |
ded77fb4 | 449 | if ((count > 1) && (inbuf[1] != '\n') && (inbuf[1] != '\0')) |
1da177e4 | 450 | return -EINVAL; |
1da177e4 LT |
451 | dev_info = container_of(dev, struct dcssblk_dev_info, dev); |
452 | ||
453 | down_write(&dcssblk_devices_sem); | |
454 | if (inbuf[0] == '1') { | |
455 | if (atomic_read(&dev_info->use_count) == 0) { | |
456 | // device is idle => we save immediately | |
b2300b9e | 457 | PRINT_INFO("Saving segment(s) of the device %s\n", |
1da177e4 | 458 | dev_info->segment_name); |
b2300b9e HY |
459 | list_for_each_entry(entry, &dev_info->seg_list, lh) { |
460 | segment_save(entry->segment_name); | |
461 | } | |
1da177e4 LT |
462 | } else { |
463 | // device is busy => we save it when it becomes | |
464 | // idle in dcssblk_release | |
b2300b9e HY |
465 | PRINT_INFO("Device %s is currently busy, segment(s) " |
466 | "will be saved when it becomes idle...\n", | |
1da177e4 LT |
467 | dev_info->segment_name); |
468 | dev_info->save_pending = 1; | |
469 | } | |
470 | } else if (inbuf[0] == '0') { | |
471 | if (dev_info->save_pending) { | |
472 | // device is busy & the user wants to undo his save | |
473 | // request | |
474 | dev_info->save_pending = 0; | |
b2300b9e HY |
475 | PRINT_INFO("Pending save for segment(s) of the device " |
476 | "%s deactivated\n", | |
1da177e4 LT |
477 | dev_info->segment_name); |
478 | } | |
479 | } else { | |
480 | up_write(&dcssblk_devices_sem); | |
1da177e4 LT |
481 | return -EINVAL; |
482 | } | |
483 | up_write(&dcssblk_devices_sem); | |
484 | return count; | |
485 | } | |
486 | ||
b2300b9e HY |
487 | /* |
488 | * device attribute for showing all segments in a device | |
489 | */ | |
490 | static ssize_t | |
491 | dcssblk_seglist_show(struct device *dev, struct device_attribute *attr, | |
492 | char *buf) | |
493 | { | |
494 | int i; | |
495 | ||
496 | struct dcssblk_dev_info *dev_info; | |
497 | struct segment_info *entry; | |
498 | ||
499 | down_read(&dcssblk_devices_sem); | |
500 | dev_info = container_of(dev, struct dcssblk_dev_info, dev); | |
501 | i = 0; | |
502 | buf[0] = '\0'; | |
503 | list_for_each_entry(entry, &dev_info->seg_list, lh) { | |
504 | strcpy(&buf[i], entry->segment_name); | |
505 | i += strlen(entry->segment_name); | |
506 | buf[i] = '\n'; | |
507 | i++; | |
508 | } | |
509 | up_read(&dcssblk_devices_sem); | |
510 | return i; | |
511 | } | |
512 | ||
1da177e4 LT |
513 | /* |
514 | * device attribute for adding devices | |
515 | */ | |
516 | static ssize_t | |
e404e274 | 517 | dcssblk_add_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) |
1da177e4 | 518 | { |
b2300b9e | 519 | int rc, i, j, num_of_segments; |
1da177e4 | 520 | struct dcssblk_dev_info *dev_info; |
b2300b9e | 521 | struct segment_info *seg_info, *temp; |
1da177e4 LT |
522 | char *local_buf; |
523 | unsigned long seg_byte_size; | |
524 | ||
525 | dev_info = NULL; | |
b2300b9e | 526 | seg_info = NULL; |
1da177e4 LT |
527 | if (dev != dcssblk_root_dev) { |
528 | rc = -EINVAL; | |
529 | goto out_nobuf; | |
530 | } | |
b2300b9e HY |
531 | if ((count < 1) || (buf[0] == '\0') || (buf[0] == '\n')) { |
532 | rc = -ENAMETOOLONG; | |
533 | goto out_nobuf; | |
534 | } | |
535 | ||
1da177e4 LT |
536 | local_buf = kmalloc(count + 1, GFP_KERNEL); |
537 | if (local_buf == NULL) { | |
538 | rc = -ENOMEM; | |
539 | goto out_nobuf; | |
540 | } | |
b2300b9e | 541 | |
1da177e4 LT |
542 | /* |
543 | * parse input | |
544 | */ | |
b2300b9e | 545 | num_of_segments = 0; |
1da177e4 | 546 | for (i = 0; ((buf[i] != '\0') && (buf[i] != '\n') && i < count); i++) { |
b2300b9e HY |
547 | for (j = i; (buf[j] != ':') && |
548 | (buf[j] != '\0') && | |
549 | (buf[j] != '\n') && | |
550 | j < count; j++) { | |
551 | local_buf[j-i] = toupper(buf[j]); | |
552 | } | |
553 | local_buf[j-i] = '\0'; | |
554 | if (((j - i) == 0) || ((j - i) > 8)) { | |
555 | rc = -ENAMETOOLONG; | |
556 | goto seg_list_del; | |
557 | } | |
558 | ||
559 | rc = dcssblk_load_segment(local_buf, &seg_info); | |
560 | if (rc < 0) | |
561 | goto seg_list_del; | |
562 | /* | |
563 | * get a struct dcssblk_dev_info | |
564 | */ | |
565 | if (num_of_segments == 0) { | |
566 | dev_info = kzalloc(sizeof(struct dcssblk_dev_info), | |
567 | GFP_KERNEL); | |
568 | if (dev_info == NULL) { | |
569 | rc = -ENOMEM; | |
570 | goto out; | |
571 | } | |
572 | strcpy(dev_info->segment_name, local_buf); | |
573 | dev_info->segment_type = seg_info->segment_type; | |
574 | INIT_LIST_HEAD(&dev_info->seg_list); | |
575 | } | |
576 | list_add_tail(&seg_info->lh, &dev_info->seg_list); | |
577 | num_of_segments++; | |
578 | i = j; | |
579 | ||
580 | if ((buf[j] == '\0') || (buf[j] == '\n')) | |
581 | break; | |
1da177e4 | 582 | } |
b2300b9e HY |
583 | |
584 | /* no trailing colon at the end of the input */ | |
585 | if ((i > 0) && (buf[i-1] == ':')) { | |
1da177e4 | 586 | rc = -ENAMETOOLONG; |
b2300b9e | 587 | goto seg_list_del; |
1da177e4 | 588 | } |
b2300b9e HY |
589 | strlcpy(local_buf, buf, i + 1); |
590 | dev_info->num_of_segments = num_of_segments; | |
591 | rc = dcssblk_is_continuous(dev_info); | |
592 | if (rc < 0) | |
593 | goto seg_list_del; | |
594 | ||
595 | dev_info->start = dcssblk_find_lowest_addr(dev_info); | |
596 | dev_info->end = dcssblk_find_highest_addr(dev_info); | |
1da177e4 | 597 | |
b2300b9e | 598 | dev_set_name(&dev_info->dev, dev_info->segment_name); |
1da177e4 LT |
599 | dev_info->dev.release = dcssblk_release_segment; |
600 | INIT_LIST_HEAD(&dev_info->lh); | |
1da177e4 LT |
601 | dev_info->gd = alloc_disk(DCSSBLK_MINORS_PER_DISK); |
602 | if (dev_info->gd == NULL) { | |
603 | rc = -ENOMEM; | |
b2300b9e | 604 | goto seg_list_del; |
1da177e4 LT |
605 | } |
606 | dev_info->gd->major = dcssblk_major; | |
607 | dev_info->gd->fops = &dcssblk_devops; | |
608 | dev_info->dcssblk_queue = blk_alloc_queue(GFP_KERNEL); | |
609 | dev_info->gd->queue = dev_info->dcssblk_queue; | |
610 | dev_info->gd->private_data = dev_info; | |
611 | dev_info->gd->driverfs_dev = &dev_info->dev; | |
c5411dba HC |
612 | blk_queue_make_request(dev_info->dcssblk_queue, dcssblk_make_request); |
613 | blk_queue_hardsect_size(dev_info->dcssblk_queue, 4096); | |
b2300b9e | 614 | |
1da177e4 LT |
615 | seg_byte_size = (dev_info->end - dev_info->start + 1); |
616 | set_capacity(dev_info->gd, seg_byte_size >> 9); // size in sectors | |
b2300b9e | 617 | PRINT_INFO("Loaded segment(s) %s, size = %lu Byte, " |
1da177e4 LT |
618 | "capacity = %lu (512 Byte) sectors\n", local_buf, |
619 | seg_byte_size, seg_byte_size >> 9); | |
620 | ||
1da177e4 LT |
621 | dev_info->save_pending = 0; |
622 | dev_info->is_shared = 1; | |
623 | dev_info->dev.parent = dcssblk_root_dev; | |
624 | ||
625 | /* | |
b2300b9e | 626 | *get minor, add to list |
1da177e4 LT |
627 | */ |
628 | down_write(&dcssblk_devices_sem); | |
b2300b9e | 629 | if (dcssblk_get_segment_by_name(local_buf)) { |
04f64b57 | 630 | rc = -EEXIST; |
b2300b9e | 631 | goto release_gd; |
04f64b57 | 632 | } |
1da177e4 | 633 | rc = dcssblk_assign_free_minor(dev_info); |
b2300b9e HY |
634 | if (rc) |
635 | goto release_gd; | |
1da177e4 | 636 | sprintf(dev_info->gd->disk_name, "dcssblk%d", |
f331c029 | 637 | MINOR(disk_devt(dev_info->gd))); |
1da177e4 LT |
638 | list_add_tail(&dev_info->lh, &dcssblk_devices); |
639 | ||
640 | if (!try_module_get(THIS_MODULE)) { | |
641 | rc = -ENODEV; | |
b2300b9e | 642 | goto dev_list_del; |
1da177e4 LT |
643 | } |
644 | /* | |
645 | * register the device | |
646 | */ | |
647 | rc = device_register(&dev_info->dev); | |
648 | if (rc) { | |
1da177e4 | 649 | module_put(THIS_MODULE); |
b2300b9e | 650 | goto dev_list_del; |
1da177e4 LT |
651 | } |
652 | get_device(&dev_info->dev); | |
653 | rc = device_create_file(&dev_info->dev, &dev_attr_shared); | |
654 | if (rc) | |
655 | goto unregister_dev; | |
656 | rc = device_create_file(&dev_info->dev, &dev_attr_save); | |
b2300b9e HY |
657 | if (rc) |
658 | goto unregister_dev; | |
659 | rc = device_create_file(&dev_info->dev, &dev_attr_seglist); | |
1da177e4 LT |
660 | if (rc) |
661 | goto unregister_dev; | |
662 | ||
436d1bc7 CB |
663 | add_disk(dev_info->gd); |
664 | ||
1da177e4 LT |
665 | switch (dev_info->segment_type) { |
666 | case SEG_TYPE_SR: | |
667 | case SEG_TYPE_ER: | |
668 | case SEG_TYPE_SC: | |
669 | set_disk_ro(dev_info->gd,1); | |
670 | break; | |
671 | default: | |
672 | set_disk_ro(dev_info->gd,0); | |
673 | break; | |
674 | } | |
1da177e4 LT |
675 | up_write(&dcssblk_devices_sem); |
676 | rc = count; | |
677 | goto out; | |
678 | ||
679 | unregister_dev: | |
1da177e4 | 680 | list_del(&dev_info->lh); |
1312f40e | 681 | blk_cleanup_queue(dev_info->dcssblk_queue); |
1da177e4 LT |
682 | dev_info->gd->queue = NULL; |
683 | put_disk(dev_info->gd); | |
684 | device_unregister(&dev_info->dev); | |
b2300b9e HY |
685 | list_for_each_entry(seg_info, &dev_info->seg_list, lh) { |
686 | segment_unload(seg_info->segment_name); | |
687 | } | |
1da177e4 LT |
688 | put_device(&dev_info->dev); |
689 | up_write(&dcssblk_devices_sem); | |
690 | goto out; | |
b2300b9e | 691 | dev_list_del: |
1da177e4 | 692 | list_del(&dev_info->lh); |
b2300b9e | 693 | release_gd: |
1312f40e | 694 | blk_cleanup_queue(dev_info->dcssblk_queue); |
1da177e4 LT |
695 | dev_info->gd->queue = NULL; |
696 | put_disk(dev_info->gd); | |
b2300b9e HY |
697 | up_write(&dcssblk_devices_sem); |
698 | seg_list_del: | |
699 | if (dev_info == NULL) | |
700 | goto out; | |
701 | list_for_each_entry_safe(seg_info, temp, &dev_info->seg_list, lh) { | |
702 | list_del(&seg_info->lh); | |
703 | segment_unload(seg_info->segment_name); | |
704 | kfree(seg_info); | |
705 | } | |
1da177e4 LT |
706 | kfree(dev_info); |
707 | out: | |
708 | kfree(local_buf); | |
709 | out_nobuf: | |
710 | return rc; | |
711 | } | |
712 | ||
713 | /* | |
714 | * device attribute for removing devices | |
715 | */ | |
716 | static ssize_t | |
e404e274 | 717 | dcssblk_remove_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) |
1da177e4 LT |
718 | { |
719 | struct dcssblk_dev_info *dev_info; | |
b2300b9e | 720 | struct segment_info *entry; |
1da177e4 LT |
721 | int rc, i; |
722 | char *local_buf; | |
723 | ||
724 | if (dev != dcssblk_root_dev) { | |
725 | return -EINVAL; | |
726 | } | |
727 | local_buf = kmalloc(count + 1, GFP_KERNEL); | |
728 | if (local_buf == NULL) { | |
729 | return -ENOMEM; | |
730 | } | |
731 | /* | |
732 | * parse input | |
733 | */ | |
734 | for (i = 0; ((*(buf+i)!='\0') && (*(buf+i)!='\n') && i < count); i++) { | |
735 | local_buf[i] = toupper(buf[i]); | |
736 | } | |
737 | local_buf[i] = '\0'; | |
738 | if ((i == 0) || (i > 8)) { | |
739 | rc = -ENAMETOOLONG; | |
740 | goto out_buf; | |
741 | } | |
742 | ||
743 | down_write(&dcssblk_devices_sem); | |
744 | dev_info = dcssblk_get_device_by_name(local_buf); | |
745 | if (dev_info == NULL) { | |
746 | up_write(&dcssblk_devices_sem); | |
b2300b9e | 747 | PRINT_WARN("Device %s is not loaded!\n", local_buf); |
1da177e4 LT |
748 | rc = -ENODEV; |
749 | goto out_buf; | |
750 | } | |
751 | if (atomic_read(&dev_info->use_count) != 0) { | |
752 | up_write(&dcssblk_devices_sem); | |
b2300b9e | 753 | PRINT_WARN("Device %s is in use!\n", local_buf); |
1da177e4 LT |
754 | rc = -EBUSY; |
755 | goto out_buf; | |
756 | } | |
1da177e4 | 757 | |
b2300b9e | 758 | list_del(&dev_info->lh); |
1da177e4 | 759 | del_gendisk(dev_info->gd); |
1312f40e | 760 | blk_cleanup_queue(dev_info->dcssblk_queue); |
1da177e4 LT |
761 | dev_info->gd->queue = NULL; |
762 | put_disk(dev_info->gd); | |
763 | device_unregister(&dev_info->dev); | |
b2300b9e HY |
764 | |
765 | /* unload all related segments */ | |
766 | list_for_each_entry(entry, &dev_info->seg_list, lh) | |
767 | segment_unload(entry->segment_name); | |
768 | ||
1da177e4 LT |
769 | put_device(&dev_info->dev); |
770 | up_write(&dcssblk_devices_sem); | |
771 | ||
772 | rc = count; | |
773 | out_buf: | |
774 | kfree(local_buf); | |
775 | return rc; | |
776 | } | |
777 | ||
778 | static int | |
46d74326 | 779 | dcssblk_open(struct block_device *bdev, fmode_t mode) |
1da177e4 LT |
780 | { |
781 | struct dcssblk_dev_info *dev_info; | |
782 | int rc; | |
783 | ||
46d74326 | 784 | dev_info = bdev->bd_disk->private_data; |
1da177e4 LT |
785 | if (NULL == dev_info) { |
786 | rc = -ENODEV; | |
787 | goto out; | |
788 | } | |
789 | atomic_inc(&dev_info->use_count); | |
46d74326 | 790 | bdev->bd_block_size = 4096; |
1da177e4 LT |
791 | rc = 0; |
792 | out: | |
793 | return rc; | |
794 | } | |
795 | ||
796 | static int | |
46d74326 | 797 | dcssblk_release(struct gendisk *disk, fmode_t mode) |
1da177e4 | 798 | { |
46d74326 | 799 | struct dcssblk_dev_info *dev_info = disk->private_data; |
b2300b9e | 800 | struct segment_info *entry; |
1da177e4 LT |
801 | int rc; |
802 | ||
46d74326 | 803 | if (!dev_info) { |
1da177e4 LT |
804 | rc = -ENODEV; |
805 | goto out; | |
806 | } | |
807 | down_write(&dcssblk_devices_sem); | |
808 | if (atomic_dec_and_test(&dev_info->use_count) | |
809 | && (dev_info->save_pending)) { | |
b2300b9e | 810 | PRINT_INFO("Device %s became idle and is being saved now\n", |
1da177e4 | 811 | dev_info->segment_name); |
b2300b9e HY |
812 | list_for_each_entry(entry, &dev_info->seg_list, lh) { |
813 | segment_save(entry->segment_name); | |
814 | } | |
1da177e4 LT |
815 | dev_info->save_pending = 0; |
816 | } | |
817 | up_write(&dcssblk_devices_sem); | |
818 | rc = 0; | |
819 | out: | |
820 | return rc; | |
821 | } | |
822 | ||
823 | static int | |
165125e1 | 824 | dcssblk_make_request(struct request_queue *q, struct bio *bio) |
1da177e4 LT |
825 | { |
826 | struct dcssblk_dev_info *dev_info; | |
827 | struct bio_vec *bvec; | |
828 | unsigned long index; | |
829 | unsigned long page_addr; | |
830 | unsigned long source_addr; | |
831 | unsigned long bytes_done; | |
832 | int i; | |
833 | ||
834 | bytes_done = 0; | |
835 | dev_info = bio->bi_bdev->bd_disk->private_data; | |
836 | if (dev_info == NULL) | |
837 | goto fail; | |
838 | if ((bio->bi_sector & 7) != 0 || (bio->bi_size & 4095) != 0) | |
839 | /* Request is not page-aligned. */ | |
840 | goto fail; | |
841 | if (((bio->bi_size >> 9) + bio->bi_sector) | |
842 | > get_capacity(bio->bi_bdev->bd_disk)) { | |
843 | /* Request beyond end of DCSS segment. */ | |
844 | goto fail; | |
845 | } | |
420edbcc CO |
846 | /* verify data transfer direction */ |
847 | if (dev_info->is_shared) { | |
848 | switch (dev_info->segment_type) { | |
849 | case SEG_TYPE_SR: | |
850 | case SEG_TYPE_ER: | |
851 | case SEG_TYPE_SC: | |
852 | /* cannot write to these segments */ | |
853 | if (bio_data_dir(bio) == WRITE) { | |
b2300b9e | 854 | PRINT_WARN("rejecting write to ro device %s\n", |
2a0217d5 | 855 | dev_name(&dev_info->dev)); |
420edbcc CO |
856 | goto fail; |
857 | } | |
858 | } | |
859 | } | |
860 | ||
1da177e4 LT |
861 | index = (bio->bi_sector >> 3); |
862 | bio_for_each_segment(bvec, bio, i) { | |
863 | page_addr = (unsigned long) | |
864 | page_address(bvec->bv_page) + bvec->bv_offset; | |
865 | source_addr = dev_info->start + (index<<12) + bytes_done; | |
39f73b28 | 866 | if (unlikely((page_addr & 4095) != 0) || (bvec->bv_len & 4095) != 0) |
1da177e4 LT |
867 | // More paranoia. |
868 | goto fail; | |
869 | if (bio_data_dir(bio) == READ) { | |
870 | memcpy((void*)page_addr, (void*)source_addr, | |
871 | bvec->bv_len); | |
872 | } else { | |
873 | memcpy((void*)source_addr, (void*)page_addr, | |
874 | bvec->bv_len); | |
875 | } | |
876 | bytes_done += bvec->bv_len; | |
877 | } | |
6712ecf8 | 878 | bio_endio(bio, 0); |
1da177e4 LT |
879 | return 0; |
880 | fail: | |
6712ecf8 | 881 | bio_io_error(bio); |
420edbcc CO |
882 | return 0; |
883 | } | |
884 | ||
885 | static int | |
886 | dcssblk_direct_access (struct block_device *bdev, sector_t secnum, | |
30afcb4b | 887 | void **kaddr, unsigned long *pfn) |
420edbcc CO |
888 | { |
889 | struct dcssblk_dev_info *dev_info; | |
890 | unsigned long pgoff; | |
891 | ||
892 | dev_info = bdev->bd_disk->private_data; | |
893 | if (!dev_info) | |
894 | return -ENODEV; | |
895 | if (secnum % (PAGE_SIZE/512)) | |
896 | return -EINVAL; | |
897 | pgoff = secnum / (PAGE_SIZE / 512); | |
898 | if ((pgoff+1)*PAGE_SIZE-1 > dev_info->end - dev_info->start) | |
899 | return -ERANGE; | |
30afcb4b JH |
900 | *kaddr = (void *) (dev_info->start+pgoff*PAGE_SIZE); |
901 | *pfn = virt_to_phys(*kaddr) >> PAGE_SHIFT; | |
902 | ||
1da177e4 LT |
903 | return 0; |
904 | } | |
905 | ||
906 | static void | |
907 | dcssblk_check_params(void) | |
908 | { | |
909 | int rc, i, j, k; | |
b2300b9e | 910 | char buf[DCSSBLK_PARM_LEN + 1]; |
1da177e4 LT |
911 | struct dcssblk_dev_info *dev_info; |
912 | ||
913 | for (i = 0; (i < DCSSBLK_PARM_LEN) && (dcssblk_segments[i] != '\0'); | |
914 | i++) { | |
915 | for (j = i; (dcssblk_segments[j] != ',') && | |
916 | (dcssblk_segments[j] != '\0') && | |
917 | (dcssblk_segments[j] != '(') && | |
b2300b9e | 918 | (j < DCSSBLK_PARM_LEN); j++) |
1da177e4 LT |
919 | { |
920 | buf[j-i] = dcssblk_segments[j]; | |
921 | } | |
922 | buf[j-i] = '\0'; | |
f901e5d1 | 923 | rc = dcssblk_add_store(dcssblk_root_dev, NULL, buf, j-i); |
1da177e4 | 924 | if ((rc >= 0) && (dcssblk_segments[j] == '(')) { |
b2300b9e | 925 | for (k = 0; (buf[k] != ':') && (buf[k] != '\0'); k++) |
1da177e4 | 926 | buf[k] = toupper(buf[k]); |
b2300b9e | 927 | buf[k] = '\0'; |
1da177e4 LT |
928 | if (!strncmp(&dcssblk_segments[j], "(local)", 7)) { |
929 | down_read(&dcssblk_devices_sem); | |
930 | dev_info = dcssblk_get_device_by_name(buf); | |
931 | up_read(&dcssblk_devices_sem); | |
932 | if (dev_info) | |
933 | dcssblk_shared_store(&dev_info->dev, | |
f901e5d1 | 934 | NULL, "0\n", 2); |
1da177e4 LT |
935 | } |
936 | } | |
937 | while ((dcssblk_segments[j] != ',') && | |
938 | (dcssblk_segments[j] != '\0')) | |
939 | { | |
940 | j++; | |
941 | } | |
942 | if (dcssblk_segments[j] == '\0') | |
943 | break; | |
944 | i = j; | |
945 | } | |
946 | } | |
947 | ||
948 | /* | |
949 | * The init/exit functions. | |
950 | */ | |
951 | static void __exit | |
952 | dcssblk_exit(void) | |
953 | { | |
1da177e4 | 954 | s390_root_dev_unregister(dcssblk_root_dev); |
00d59405 | 955 | unregister_blkdev(dcssblk_major, DCSSBLK_NAME); |
1da177e4 LT |
956 | } |
957 | ||
958 | static int __init | |
959 | dcssblk_init(void) | |
960 | { | |
961 | int rc; | |
962 | ||
1da177e4 | 963 | dcssblk_root_dev = s390_root_dev_register("dcssblk"); |
ded77fb4 | 964 | if (IS_ERR(dcssblk_root_dev)) |
1da177e4 | 965 | return PTR_ERR(dcssblk_root_dev); |
1da177e4 LT |
966 | rc = device_create_file(dcssblk_root_dev, &dev_attr_add); |
967 | if (rc) { | |
1da177e4 LT |
968 | s390_root_dev_unregister(dcssblk_root_dev); |
969 | return rc; | |
970 | } | |
971 | rc = device_create_file(dcssblk_root_dev, &dev_attr_remove); | |
972 | if (rc) { | |
1da177e4 LT |
973 | s390_root_dev_unregister(dcssblk_root_dev); |
974 | return rc; | |
975 | } | |
976 | rc = register_blkdev(0, DCSSBLK_NAME); | |
977 | if (rc < 0) { | |
1da177e4 LT |
978 | s390_root_dev_unregister(dcssblk_root_dev); |
979 | return rc; | |
980 | } | |
981 | dcssblk_major = rc; | |
982 | init_rwsem(&dcssblk_devices_sem); | |
983 | ||
984 | dcssblk_check_params(); | |
985 | ||
1da177e4 LT |
986 | return 0; |
987 | } | |
988 | ||
989 | module_init(dcssblk_init); | |
990 | module_exit(dcssblk_exit); | |
991 | ||
992 | module_param_string(segments, dcssblk_segments, DCSSBLK_PARM_LEN, 0444); | |
993 | MODULE_PARM_DESC(segments, "Name of DCSS segment(s) to be loaded, " | |
b2300b9e HY |
994 | "comma-separated list, names in each set separated " |
995 | "by commas are separated by colons, each set contains " | |
996 | "names of contiguous segments and each name max. 8 chars.\n" | |
997 | "Adding \"(local)\" to the end of each set equals echoing 0 " | |
998 | "to /sys/devices/dcssblk/<device name>/shared after loading " | |
999 | "the contiguous segments - \n" | |
1000 | "e.g. segments=\"mydcss1,mydcss2:mydcss3,mydcss4(local)\""); | |
1da177e4 LT |
1001 | |
1002 | MODULE_LICENSE("GPL"); |