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Commit | Line | Data |
---|---|---|
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 | ||
93098bf0 HY |
7 | #define KMSG_COMPONENT "dcssblk" |
8 | #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt | |
9 | ||
1da177e4 LT |
10 | #include <linux/module.h> |
11 | #include <linux/moduleparam.h> | |
12 | #include <linux/ctype.h> | |
13 | #include <linux/errno.h> | |
14 | #include <linux/init.h> | |
15 | #include <linux/slab.h> | |
16 | #include <linux/blkdev.h> | |
17 | #include <asm/extmem.h> | |
18 | #include <asm/io.h> | |
19 | #include <linux/completion.h> | |
20 | #include <linux/interrupt.h> | |
1da177e4 | 21 | |
1da177e4 LT |
22 | #define DCSSBLK_NAME "dcssblk" |
23 | #define DCSSBLK_MINORS_PER_DISK 1 | |
24 | #define DCSSBLK_PARM_LEN 400 | |
98df67b3 | 25 | #define DCSS_BUS_ID_SIZE 20 |
1da177e4 | 26 | |
46d74326 AV |
27 | static int dcssblk_open(struct block_device *bdev, fmode_t mode); |
28 | static int dcssblk_release(struct gendisk *disk, fmode_t mode); | |
1da177e4 | 29 | static int dcssblk_make_request(struct request_queue *q, struct bio *bio); |
420edbcc | 30 | static int dcssblk_direct_access(struct block_device *bdev, sector_t secnum, |
30afcb4b | 31 | void **kaddr, unsigned long *pfn); |
1da177e4 LT |
32 | |
33 | static char dcssblk_segments[DCSSBLK_PARM_LEN] = "\0"; | |
34 | ||
35 | static int dcssblk_major; | |
36 | static struct block_device_operations dcssblk_devops = { | |
420edbcc | 37 | .owner = THIS_MODULE, |
46d74326 AV |
38 | .open = dcssblk_open, |
39 | .release = dcssblk_release, | |
420edbcc | 40 | .direct_access = dcssblk_direct_access, |
1da177e4 LT |
41 | }; |
42 | ||
b2300b9e HY |
43 | struct dcssblk_dev_info { |
44 | struct list_head lh; | |
45 | struct device dev; | |
98df67b3 | 46 | char segment_name[DCSS_BUS_ID_SIZE]; |
b2300b9e HY |
47 | atomic_t use_count; |
48 | struct gendisk *gd; | |
49 | unsigned long start; | |
50 | unsigned long end; | |
51 | int segment_type; | |
52 | unsigned char save_pending; | |
53 | unsigned char is_shared; | |
54 | struct request_queue *dcssblk_queue; | |
55 | int num_of_segments; | |
56 | struct list_head seg_list; | |
57 | }; | |
58 | ||
59 | struct segment_info { | |
60 | struct list_head lh; | |
98df67b3 | 61 | char segment_name[DCSS_BUS_ID_SIZE]; |
b2300b9e HY |
62 | unsigned long start; |
63 | unsigned long end; | |
64 | int segment_type; | |
65 | }; | |
66 | ||
e404e274 | 67 | static ssize_t dcssblk_add_store(struct device * dev, struct device_attribute *attr, const char * buf, |
1da177e4 | 68 | size_t count); |
e404e274 | 69 | static ssize_t dcssblk_remove_store(struct device * dev, struct device_attribute *attr, const char * buf, |
1da177e4 | 70 | size_t count); |
e404e274 | 71 | static ssize_t dcssblk_save_store(struct device * dev, struct device_attribute *attr, const char * buf, |
1da177e4 | 72 | size_t count); |
e404e274 YI |
73 | static ssize_t dcssblk_save_show(struct device *dev, struct device_attribute *attr, char *buf); |
74 | static ssize_t dcssblk_shared_store(struct device * dev, struct device_attribute *attr, const char * buf, | |
1da177e4 | 75 | size_t count); |
e404e274 | 76 | static ssize_t dcssblk_shared_show(struct device *dev, struct device_attribute *attr, char *buf); |
b2300b9e HY |
77 | static ssize_t dcssblk_seglist_show(struct device *dev, |
78 | struct device_attribute *attr, | |
79 | char *buf); | |
1da177e4 LT |
80 | |
81 | static DEVICE_ATTR(add, S_IWUSR, NULL, dcssblk_add_store); | |
82 | static DEVICE_ATTR(remove, S_IWUSR, NULL, dcssblk_remove_store); | |
b2300b9e | 83 | static DEVICE_ATTR(save, S_IWUSR | S_IRUSR, dcssblk_save_show, |
1da177e4 | 84 | dcssblk_save_store); |
b2300b9e | 85 | static DEVICE_ATTR(shared, S_IWUSR | S_IRUSR, dcssblk_shared_show, |
1da177e4 | 86 | dcssblk_shared_store); |
b2300b9e | 87 | static DEVICE_ATTR(seglist, S_IRUSR, dcssblk_seglist_show, NULL); |
1da177e4 LT |
88 | |
89 | static struct device *dcssblk_root_dev; | |
90 | ||
c11ca97e | 91 | static LIST_HEAD(dcssblk_devices); |
1da177e4 LT |
92 | static struct rw_semaphore dcssblk_devices_sem; |
93 | ||
94 | /* | |
95 | * release function for segment device. | |
96 | */ | |
97 | static void | |
98 | dcssblk_release_segment(struct device *dev) | |
99 | { | |
b2300b9e HY |
100 | struct dcssblk_dev_info *dev_info; |
101 | struct segment_info *entry, *temp; | |
102 | ||
103 | dev_info = container_of(dev, struct dcssblk_dev_info, dev); | |
104 | list_for_each_entry_safe(entry, temp, &dev_info->seg_list, lh) { | |
105 | list_del(&entry->lh); | |
106 | kfree(entry); | |
107 | } | |
108 | kfree(dev_info); | |
1da177e4 LT |
109 | module_put(THIS_MODULE); |
110 | } | |
111 | ||
112 | /* | |
113 | * get a minor number. needs to be called with | |
114 | * down_write(&dcssblk_devices_sem) and the | |
115 | * device needs to be enqueued before the semaphore is | |
116 | * freed. | |
117 | */ | |
4d284cac | 118 | static int |
1da177e4 LT |
119 | dcssblk_assign_free_minor(struct dcssblk_dev_info *dev_info) |
120 | { | |
121 | int minor, found; | |
122 | struct dcssblk_dev_info *entry; | |
123 | ||
124 | if (dev_info == NULL) | |
125 | return -EINVAL; | |
126 | for (minor = 0; minor < (1<<MINORBITS); minor++) { | |
127 | found = 0; | |
128 | // test if minor available | |
129 | list_for_each_entry(entry, &dcssblk_devices, lh) | |
f331c029 | 130 | if (minor == MINOR(disk_devt(entry->gd))) |
1da177e4 LT |
131 | found++; |
132 | if (!found) break; // got unused minor | |
133 | } | |
134 | if (found) | |
135 | return -EBUSY; | |
136 | dev_info->gd->first_minor = minor; | |
137 | return 0; | |
138 | } | |
139 | ||
140 | /* | |
141 | * get the struct dcssblk_dev_info from dcssblk_devices | |
142 | * for the given name. | |
143 | * down_read(&dcssblk_devices_sem) must be held. | |
144 | */ | |
145 | static struct dcssblk_dev_info * | |
146 | dcssblk_get_device_by_name(char *name) | |
147 | { | |
148 | struct dcssblk_dev_info *entry; | |
149 | ||
150 | list_for_each_entry(entry, &dcssblk_devices, lh) { | |
151 | if (!strcmp(name, entry->segment_name)) { | |
152 | return entry; | |
153 | } | |
154 | } | |
155 | return NULL; | |
156 | } | |
157 | ||
b2300b9e HY |
158 | /* |
159 | * get the struct segment_info from seg_list | |
160 | * for the given name. | |
161 | * down_read(&dcssblk_devices_sem) must be held. | |
162 | */ | |
163 | static struct segment_info * | |
164 | dcssblk_get_segment_by_name(char *name) | |
165 | { | |
166 | struct dcssblk_dev_info *dev_info; | |
167 | struct segment_info *entry; | |
168 | ||
169 | list_for_each_entry(dev_info, &dcssblk_devices, lh) { | |
170 | list_for_each_entry(entry, &dev_info->seg_list, lh) { | |
171 | if (!strcmp(name, entry->segment_name)) | |
172 | return entry; | |
173 | } | |
174 | } | |
175 | return NULL; | |
176 | } | |
177 | ||
178 | /* | |
179 | * get the highest address of the multi-segment block. | |
180 | */ | |
181 | static unsigned long | |
182 | dcssblk_find_highest_addr(struct dcssblk_dev_info *dev_info) | |
183 | { | |
184 | unsigned long highest_addr; | |
185 | struct segment_info *entry; | |
186 | ||
187 | highest_addr = 0; | |
188 | list_for_each_entry(entry, &dev_info->seg_list, lh) { | |
189 | if (highest_addr < entry->end) | |
190 | highest_addr = entry->end; | |
191 | } | |
192 | return highest_addr; | |
193 | } | |
194 | ||
195 | /* | |
196 | * get the lowest address of the multi-segment block. | |
197 | */ | |
198 | static unsigned long | |
199 | dcssblk_find_lowest_addr(struct dcssblk_dev_info *dev_info) | |
200 | { | |
201 | int set_first; | |
202 | unsigned long lowest_addr; | |
203 | struct segment_info *entry; | |
204 | ||
205 | set_first = 0; | |
206 | lowest_addr = 0; | |
207 | list_for_each_entry(entry, &dev_info->seg_list, lh) { | |
208 | if (set_first == 0) { | |
209 | lowest_addr = entry->start; | |
210 | set_first = 1; | |
211 | } else { | |
212 | if (lowest_addr > entry->start) | |
213 | lowest_addr = entry->start; | |
214 | } | |
215 | } | |
216 | return lowest_addr; | |
217 | } | |
218 | ||
219 | /* | |
220 | * Check continuity of segments. | |
221 | */ | |
222 | static int | |
223 | dcssblk_is_continuous(struct dcssblk_dev_info *dev_info) | |
224 | { | |
225 | int i, j, rc; | |
226 | struct segment_info *sort_list, *entry, temp; | |
227 | ||
228 | if (dev_info->num_of_segments <= 1) | |
229 | return 0; | |
230 | ||
231 | sort_list = kzalloc( | |
232 | sizeof(struct segment_info) * dev_info->num_of_segments, | |
233 | GFP_KERNEL); | |
234 | if (sort_list == NULL) | |
235 | return -ENOMEM; | |
236 | i = 0; | |
237 | list_for_each_entry(entry, &dev_info->seg_list, lh) { | |
238 | memcpy(&sort_list[i], entry, sizeof(struct segment_info)); | |
239 | i++; | |
240 | } | |
241 | ||
242 | /* sort segments */ | |
243 | for (i = 0; i < dev_info->num_of_segments; i++) | |
244 | for (j = 0; j < dev_info->num_of_segments; j++) | |
245 | if (sort_list[j].start > sort_list[i].start) { | |
246 | memcpy(&temp, &sort_list[i], | |
247 | sizeof(struct segment_info)); | |
248 | memcpy(&sort_list[i], &sort_list[j], | |
249 | sizeof(struct segment_info)); | |
250 | memcpy(&sort_list[j], &temp, | |
251 | sizeof(struct segment_info)); | |
252 | } | |
253 | ||
254 | /* check continuity */ | |
255 | for (i = 0; i < dev_info->num_of_segments - 1; i++) { | |
256 | if ((sort_list[i].end + 1) != sort_list[i+1].start) { | |
93098bf0 HY |
257 | pr_err("Adjacent DCSSs %s and %s are not " |
258 | "contiguous\n", sort_list[i].segment_name, | |
259 | sort_list[i+1].segment_name); | |
b2300b9e HY |
260 | rc = -EINVAL; |
261 | goto out; | |
262 | } | |
263 | /* EN and EW are allowed in a block device */ | |
264 | if (sort_list[i].segment_type != sort_list[i+1].segment_type) { | |
265 | if (!(sort_list[i].segment_type & SEGMENT_EXCLUSIVE) || | |
266 | (sort_list[i].segment_type == SEG_TYPE_ER) || | |
267 | !(sort_list[i+1].segment_type & | |
268 | SEGMENT_EXCLUSIVE) || | |
269 | (sort_list[i+1].segment_type == SEG_TYPE_ER)) { | |
93098bf0 HY |
270 | pr_err("DCSS %s and DCSS %s have " |
271 | "incompatible types\n", | |
272 | sort_list[i].segment_name, | |
273 | sort_list[i+1].segment_name); | |
b2300b9e HY |
274 | rc = -EINVAL; |
275 | goto out; | |
276 | } | |
277 | } | |
278 | } | |
279 | rc = 0; | |
280 | out: | |
281 | kfree(sort_list); | |
282 | return rc; | |
283 | } | |
284 | ||
285 | /* | |
286 | * Load a segment | |
287 | */ | |
288 | static int | |
289 | dcssblk_load_segment(char *name, struct segment_info **seg_info) | |
290 | { | |
291 | int rc; | |
292 | ||
293 | /* already loaded? */ | |
294 | down_read(&dcssblk_devices_sem); | |
295 | *seg_info = dcssblk_get_segment_by_name(name); | |
296 | up_read(&dcssblk_devices_sem); | |
297 | if (*seg_info != NULL) | |
298 | return -EEXIST; | |
299 | ||
300 | /* get a struct segment_info */ | |
301 | *seg_info = kzalloc(sizeof(struct segment_info), GFP_KERNEL); | |
302 | if (*seg_info == NULL) | |
303 | return -ENOMEM; | |
304 | ||
305 | strcpy((*seg_info)->segment_name, name); | |
306 | ||
307 | /* load the segment */ | |
308 | rc = segment_load(name, SEGMENT_SHARED, | |
309 | &(*seg_info)->start, &(*seg_info)->end); | |
310 | if (rc < 0) { | |
311 | segment_warning(rc, (*seg_info)->segment_name); | |
312 | kfree(*seg_info); | |
313 | } else { | |
314 | INIT_LIST_HEAD(&(*seg_info)->lh); | |
315 | (*seg_info)->segment_type = rc; | |
316 | } | |
317 | return rc; | |
318 | } | |
319 | ||
931bb68b GS |
320 | static void dcssblk_unregister_callback(struct device *dev) |
321 | { | |
322 | device_unregister(dev); | |
323 | put_device(dev); | |
324 | } | |
325 | ||
1da177e4 LT |
326 | /* |
327 | * device attribute for switching shared/nonshared (exclusive) | |
328 | * operation (show + store) | |
329 | */ | |
330 | static ssize_t | |
e404e274 | 331 | dcssblk_shared_show(struct device *dev, struct device_attribute *attr, char *buf) |
1da177e4 LT |
332 | { |
333 | struct dcssblk_dev_info *dev_info; | |
334 | ||
335 | dev_info = container_of(dev, struct dcssblk_dev_info, dev); | |
336 | return sprintf(buf, dev_info->is_shared ? "1\n" : "0\n"); | |
337 | } | |
338 | ||
339 | static ssize_t | |
e404e274 | 340 | dcssblk_shared_store(struct device *dev, struct device_attribute *attr, const char *inbuf, size_t count) |
1da177e4 LT |
341 | { |
342 | struct dcssblk_dev_info *dev_info; | |
b2300b9e | 343 | struct segment_info *entry, *temp; |
1da177e4 LT |
344 | int rc; |
345 | ||
ded77fb4 | 346 | if ((count > 1) && (inbuf[1] != '\n') && (inbuf[1] != '\0')) |
1da177e4 | 347 | return -EINVAL; |
1da177e4 LT |
348 | down_write(&dcssblk_devices_sem); |
349 | dev_info = container_of(dev, struct dcssblk_dev_info, dev); | |
350 | if (atomic_read(&dev_info->use_count)) { | |
1da177e4 LT |
351 | rc = -EBUSY; |
352 | goto out; | |
353 | } | |
354 | if (inbuf[0] == '1') { | |
b2300b9e HY |
355 | /* reload segments in shared mode */ |
356 | list_for_each_entry(entry, &dev_info->seg_list, lh) { | |
357 | rc = segment_modify_shared(entry->segment_name, | |
358 | SEGMENT_SHARED); | |
359 | if (rc < 0) { | |
360 | BUG_ON(rc == -EINVAL); | |
361 | if (rc != -EAGAIN) | |
362 | goto removeseg; | |
1da177e4 LT |
363 | } |
364 | } | |
b2300b9e HY |
365 | dev_info->is_shared = 1; |
366 | switch (dev_info->segment_type) { | |
367 | case SEG_TYPE_SR: | |
368 | case SEG_TYPE_ER: | |
369 | case SEG_TYPE_SC: | |
370 | set_disk_ro(dev_info->gd, 1); | |
371 | } | |
1da177e4 | 372 | } else if (inbuf[0] == '0') { |
b2300b9e | 373 | /* reload segments in exclusive mode */ |
1da177e4 | 374 | if (dev_info->segment_type == SEG_TYPE_SC) { |
93098bf0 HY |
375 | pr_err("DCSS %s is of type SC and cannot be " |
376 | "loaded as exclusive-writable\n", | |
377 | dev_info->segment_name); | |
1da177e4 LT |
378 | rc = -EINVAL; |
379 | goto out; | |
380 | } | |
b2300b9e HY |
381 | list_for_each_entry(entry, &dev_info->seg_list, lh) { |
382 | rc = segment_modify_shared(entry->segment_name, | |
383 | SEGMENT_EXCLUSIVE); | |
384 | if (rc < 0) { | |
385 | BUG_ON(rc == -EINVAL); | |
386 | if (rc != -EAGAIN) | |
387 | goto removeseg; | |
388 | } | |
1da177e4 | 389 | } |
b2300b9e HY |
390 | dev_info->is_shared = 0; |
391 | set_disk_ro(dev_info->gd, 0); | |
1da177e4 | 392 | } else { |
1da177e4 LT |
393 | rc = -EINVAL; |
394 | goto out; | |
395 | } | |
396 | rc = count; | |
397 | goto out; | |
398 | ||
399 | removeseg: | |
93098bf0 HY |
400 | pr_err("DCSS device %s is removed after a failed access mode " |
401 | "change\n", dev_info->segment_name); | |
b2300b9e HY |
402 | temp = entry; |
403 | list_for_each_entry(entry, &dev_info->seg_list, lh) { | |
404 | if (entry != temp) | |
405 | segment_unload(entry->segment_name); | |
406 | } | |
1da177e4 LT |
407 | list_del(&dev_info->lh); |
408 | ||
409 | del_gendisk(dev_info->gd); | |
1312f40e | 410 | blk_cleanup_queue(dev_info->dcssblk_queue); |
1da177e4 LT |
411 | dev_info->gd->queue = NULL; |
412 | put_disk(dev_info->gd); | |
931bb68b | 413 | rc = device_schedule_callback(dev, dcssblk_unregister_callback); |
1da177e4 LT |
414 | out: |
415 | up_write(&dcssblk_devices_sem); | |
416 | return rc; | |
417 | } | |
418 | ||
419 | /* | |
420 | * device attribute for save operation on current copy | |
421 | * of the segment. If the segment is busy, saving will | |
422 | * become pending until it gets released, which can be | |
423 | * undone by storing a non-true value to this entry. | |
424 | * (show + store) | |
425 | */ | |
426 | static ssize_t | |
e404e274 | 427 | dcssblk_save_show(struct device *dev, struct device_attribute *attr, char *buf) |
1da177e4 LT |
428 | { |
429 | struct dcssblk_dev_info *dev_info; | |
430 | ||
431 | dev_info = container_of(dev, struct dcssblk_dev_info, dev); | |
432 | return sprintf(buf, dev_info->save_pending ? "1\n" : "0\n"); | |
433 | } | |
434 | ||
435 | static ssize_t | |
e404e274 | 436 | dcssblk_save_store(struct device *dev, struct device_attribute *attr, const char *inbuf, size_t count) |
1da177e4 LT |
437 | { |
438 | struct dcssblk_dev_info *dev_info; | |
b2300b9e | 439 | struct segment_info *entry; |
1da177e4 | 440 | |
ded77fb4 | 441 | if ((count > 1) && (inbuf[1] != '\n') && (inbuf[1] != '\0')) |
1da177e4 | 442 | return -EINVAL; |
1da177e4 LT |
443 | dev_info = container_of(dev, struct dcssblk_dev_info, dev); |
444 | ||
445 | down_write(&dcssblk_devices_sem); | |
446 | if (inbuf[0] == '1') { | |
447 | if (atomic_read(&dev_info->use_count) == 0) { | |
448 | // device is idle => we save immediately | |
93098bf0 HY |
449 | pr_info("All DCSSs that map to device %s are " |
450 | "saved\n", dev_info->segment_name); | |
b2300b9e HY |
451 | list_for_each_entry(entry, &dev_info->seg_list, lh) { |
452 | segment_save(entry->segment_name); | |
453 | } | |
1da177e4 LT |
454 | } else { |
455 | // device is busy => we save it when it becomes | |
456 | // idle in dcssblk_release | |
93098bf0 HY |
457 | pr_info("Device %s is in use, its DCSSs will be " |
458 | "saved when it becomes idle\n", | |
459 | dev_info->segment_name); | |
1da177e4 LT |
460 | dev_info->save_pending = 1; |
461 | } | |
462 | } else if (inbuf[0] == '0') { | |
463 | if (dev_info->save_pending) { | |
464 | // device is busy & the user wants to undo his save | |
465 | // request | |
466 | dev_info->save_pending = 0; | |
93098bf0 HY |
467 | pr_info("A pending save request for device %s " |
468 | "has been canceled\n", | |
469 | dev_info->segment_name); | |
1da177e4 LT |
470 | } |
471 | } else { | |
472 | up_write(&dcssblk_devices_sem); | |
1da177e4 LT |
473 | return -EINVAL; |
474 | } | |
475 | up_write(&dcssblk_devices_sem); | |
476 | return count; | |
477 | } | |
478 | ||
b2300b9e HY |
479 | /* |
480 | * device attribute for showing all segments in a device | |
481 | */ | |
482 | static ssize_t | |
483 | dcssblk_seglist_show(struct device *dev, struct device_attribute *attr, | |
484 | char *buf) | |
485 | { | |
486 | int i; | |
487 | ||
488 | struct dcssblk_dev_info *dev_info; | |
489 | struct segment_info *entry; | |
490 | ||
491 | down_read(&dcssblk_devices_sem); | |
492 | dev_info = container_of(dev, struct dcssblk_dev_info, dev); | |
493 | i = 0; | |
494 | buf[0] = '\0'; | |
495 | list_for_each_entry(entry, &dev_info->seg_list, lh) { | |
496 | strcpy(&buf[i], entry->segment_name); | |
497 | i += strlen(entry->segment_name); | |
498 | buf[i] = '\n'; | |
499 | i++; | |
500 | } | |
501 | up_read(&dcssblk_devices_sem); | |
502 | return i; | |
503 | } | |
504 | ||
1da177e4 LT |
505 | /* |
506 | * device attribute for adding devices | |
507 | */ | |
508 | static ssize_t | |
e404e274 | 509 | dcssblk_add_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) |
1da177e4 | 510 | { |
b2300b9e | 511 | int rc, i, j, num_of_segments; |
1da177e4 | 512 | struct dcssblk_dev_info *dev_info; |
b2300b9e | 513 | struct segment_info *seg_info, *temp; |
1da177e4 LT |
514 | char *local_buf; |
515 | unsigned long seg_byte_size; | |
516 | ||
517 | dev_info = NULL; | |
b2300b9e | 518 | seg_info = NULL; |
1da177e4 LT |
519 | if (dev != dcssblk_root_dev) { |
520 | rc = -EINVAL; | |
521 | goto out_nobuf; | |
522 | } | |
b2300b9e HY |
523 | if ((count < 1) || (buf[0] == '\0') || (buf[0] == '\n')) { |
524 | rc = -ENAMETOOLONG; | |
525 | goto out_nobuf; | |
526 | } | |
527 | ||
1da177e4 LT |
528 | local_buf = kmalloc(count + 1, GFP_KERNEL); |
529 | if (local_buf == NULL) { | |
530 | rc = -ENOMEM; | |
531 | goto out_nobuf; | |
532 | } | |
b2300b9e | 533 | |
1da177e4 LT |
534 | /* |
535 | * parse input | |
536 | */ | |
b2300b9e | 537 | num_of_segments = 0; |
1da177e4 | 538 | for (i = 0; ((buf[i] != '\0') && (buf[i] != '\n') && i < count); i++) { |
b2300b9e HY |
539 | for (j = i; (buf[j] != ':') && |
540 | (buf[j] != '\0') && | |
541 | (buf[j] != '\n') && | |
542 | j < count; j++) { | |
543 | local_buf[j-i] = toupper(buf[j]); | |
544 | } | |
545 | local_buf[j-i] = '\0'; | |
546 | if (((j - i) == 0) || ((j - i) > 8)) { | |
547 | rc = -ENAMETOOLONG; | |
548 | goto seg_list_del; | |
549 | } | |
550 | ||
551 | rc = dcssblk_load_segment(local_buf, &seg_info); | |
552 | if (rc < 0) | |
553 | goto seg_list_del; | |
554 | /* | |
555 | * get a struct dcssblk_dev_info | |
556 | */ | |
557 | if (num_of_segments == 0) { | |
558 | dev_info = kzalloc(sizeof(struct dcssblk_dev_info), | |
559 | GFP_KERNEL); | |
560 | if (dev_info == NULL) { | |
561 | rc = -ENOMEM; | |
562 | goto out; | |
563 | } | |
564 | strcpy(dev_info->segment_name, local_buf); | |
565 | dev_info->segment_type = seg_info->segment_type; | |
566 | INIT_LIST_HEAD(&dev_info->seg_list); | |
567 | } | |
568 | list_add_tail(&seg_info->lh, &dev_info->seg_list); | |
569 | num_of_segments++; | |
570 | i = j; | |
571 | ||
572 | if ((buf[j] == '\0') || (buf[j] == '\n')) | |
573 | break; | |
1da177e4 | 574 | } |
b2300b9e HY |
575 | |
576 | /* no trailing colon at the end of the input */ | |
577 | if ((i > 0) && (buf[i-1] == ':')) { | |
1da177e4 | 578 | rc = -ENAMETOOLONG; |
b2300b9e | 579 | goto seg_list_del; |
1da177e4 | 580 | } |
b2300b9e HY |
581 | strlcpy(local_buf, buf, i + 1); |
582 | dev_info->num_of_segments = num_of_segments; | |
583 | rc = dcssblk_is_continuous(dev_info); | |
584 | if (rc < 0) | |
585 | goto seg_list_del; | |
586 | ||
587 | dev_info->start = dcssblk_find_lowest_addr(dev_info); | |
588 | dev_info->end = dcssblk_find_highest_addr(dev_info); | |
1da177e4 | 589 | |
b2300b9e | 590 | dev_set_name(&dev_info->dev, dev_info->segment_name); |
1da177e4 LT |
591 | dev_info->dev.release = dcssblk_release_segment; |
592 | INIT_LIST_HEAD(&dev_info->lh); | |
1da177e4 LT |
593 | dev_info->gd = alloc_disk(DCSSBLK_MINORS_PER_DISK); |
594 | if (dev_info->gd == NULL) { | |
595 | rc = -ENOMEM; | |
b2300b9e | 596 | goto seg_list_del; |
1da177e4 LT |
597 | } |
598 | dev_info->gd->major = dcssblk_major; | |
599 | dev_info->gd->fops = &dcssblk_devops; | |
600 | dev_info->dcssblk_queue = blk_alloc_queue(GFP_KERNEL); | |
601 | dev_info->gd->queue = dev_info->dcssblk_queue; | |
602 | dev_info->gd->private_data = dev_info; | |
603 | dev_info->gd->driverfs_dev = &dev_info->dev; | |
c5411dba | 604 | blk_queue_make_request(dev_info->dcssblk_queue, dcssblk_make_request); |
e1defc4f | 605 | blk_queue_logical_block_size(dev_info->dcssblk_queue, 4096); |
b2300b9e | 606 | |
1da177e4 LT |
607 | seg_byte_size = (dev_info->end - dev_info->start + 1); |
608 | set_capacity(dev_info->gd, seg_byte_size >> 9); // size in sectors | |
93098bf0 HY |
609 | pr_info("Loaded %s with total size %lu bytes and capacity %lu " |
610 | "sectors\n", local_buf, seg_byte_size, seg_byte_size >> 9); | |
1da177e4 | 611 | |
1da177e4 LT |
612 | dev_info->save_pending = 0; |
613 | dev_info->is_shared = 1; | |
614 | dev_info->dev.parent = dcssblk_root_dev; | |
615 | ||
616 | /* | |
b2300b9e | 617 | *get minor, add to list |
1da177e4 LT |
618 | */ |
619 | down_write(&dcssblk_devices_sem); | |
b2300b9e | 620 | if (dcssblk_get_segment_by_name(local_buf)) { |
04f64b57 | 621 | rc = -EEXIST; |
b2300b9e | 622 | goto release_gd; |
04f64b57 | 623 | } |
1da177e4 | 624 | rc = dcssblk_assign_free_minor(dev_info); |
b2300b9e HY |
625 | if (rc) |
626 | goto release_gd; | |
1da177e4 | 627 | sprintf(dev_info->gd->disk_name, "dcssblk%d", |
f331c029 | 628 | MINOR(disk_devt(dev_info->gd))); |
1da177e4 LT |
629 | list_add_tail(&dev_info->lh, &dcssblk_devices); |
630 | ||
631 | if (!try_module_get(THIS_MODULE)) { | |
632 | rc = -ENODEV; | |
b2300b9e | 633 | goto dev_list_del; |
1da177e4 LT |
634 | } |
635 | /* | |
636 | * register the device | |
637 | */ | |
638 | rc = device_register(&dev_info->dev); | |
639 | if (rc) { | |
1da177e4 | 640 | module_put(THIS_MODULE); |
b2300b9e | 641 | goto dev_list_del; |
1da177e4 LT |
642 | } |
643 | get_device(&dev_info->dev); | |
644 | rc = device_create_file(&dev_info->dev, &dev_attr_shared); | |
645 | if (rc) | |
646 | goto unregister_dev; | |
647 | rc = device_create_file(&dev_info->dev, &dev_attr_save); | |
b2300b9e HY |
648 | if (rc) |
649 | goto unregister_dev; | |
650 | rc = device_create_file(&dev_info->dev, &dev_attr_seglist); | |
1da177e4 LT |
651 | if (rc) |
652 | goto unregister_dev; | |
653 | ||
436d1bc7 CB |
654 | add_disk(dev_info->gd); |
655 | ||
1da177e4 LT |
656 | switch (dev_info->segment_type) { |
657 | case SEG_TYPE_SR: | |
658 | case SEG_TYPE_ER: | |
659 | case SEG_TYPE_SC: | |
660 | set_disk_ro(dev_info->gd,1); | |
661 | break; | |
662 | default: | |
663 | set_disk_ro(dev_info->gd,0); | |
664 | break; | |
665 | } | |
1da177e4 LT |
666 | up_write(&dcssblk_devices_sem); |
667 | rc = count; | |
668 | goto out; | |
669 | ||
670 | unregister_dev: | |
1da177e4 | 671 | list_del(&dev_info->lh); |
1312f40e | 672 | blk_cleanup_queue(dev_info->dcssblk_queue); |
1da177e4 LT |
673 | dev_info->gd->queue = NULL; |
674 | put_disk(dev_info->gd); | |
675 | device_unregister(&dev_info->dev); | |
b2300b9e HY |
676 | list_for_each_entry(seg_info, &dev_info->seg_list, lh) { |
677 | segment_unload(seg_info->segment_name); | |
678 | } | |
1da177e4 LT |
679 | put_device(&dev_info->dev); |
680 | up_write(&dcssblk_devices_sem); | |
681 | goto out; | |
b2300b9e | 682 | dev_list_del: |
1da177e4 | 683 | list_del(&dev_info->lh); |
b2300b9e | 684 | release_gd: |
1312f40e | 685 | blk_cleanup_queue(dev_info->dcssblk_queue); |
1da177e4 LT |
686 | dev_info->gd->queue = NULL; |
687 | put_disk(dev_info->gd); | |
b2300b9e HY |
688 | up_write(&dcssblk_devices_sem); |
689 | seg_list_del: | |
690 | if (dev_info == NULL) | |
691 | goto out; | |
692 | list_for_each_entry_safe(seg_info, temp, &dev_info->seg_list, lh) { | |
693 | list_del(&seg_info->lh); | |
694 | segment_unload(seg_info->segment_name); | |
695 | kfree(seg_info); | |
696 | } | |
1da177e4 LT |
697 | kfree(dev_info); |
698 | out: | |
699 | kfree(local_buf); | |
700 | out_nobuf: | |
701 | return rc; | |
702 | } | |
703 | ||
704 | /* | |
705 | * device attribute for removing devices | |
706 | */ | |
707 | static ssize_t | |
e404e274 | 708 | dcssblk_remove_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) |
1da177e4 LT |
709 | { |
710 | struct dcssblk_dev_info *dev_info; | |
b2300b9e | 711 | struct segment_info *entry; |
1da177e4 LT |
712 | int rc, i; |
713 | char *local_buf; | |
714 | ||
715 | if (dev != dcssblk_root_dev) { | |
716 | return -EINVAL; | |
717 | } | |
718 | local_buf = kmalloc(count + 1, GFP_KERNEL); | |
719 | if (local_buf == NULL) { | |
720 | return -ENOMEM; | |
721 | } | |
722 | /* | |
723 | * parse input | |
724 | */ | |
725 | for (i = 0; ((*(buf+i)!='\0') && (*(buf+i)!='\n') && i < count); i++) { | |
726 | local_buf[i] = toupper(buf[i]); | |
727 | } | |
728 | local_buf[i] = '\0'; | |
729 | if ((i == 0) || (i > 8)) { | |
730 | rc = -ENAMETOOLONG; | |
731 | goto out_buf; | |
732 | } | |
733 | ||
734 | down_write(&dcssblk_devices_sem); | |
735 | dev_info = dcssblk_get_device_by_name(local_buf); | |
736 | if (dev_info == NULL) { | |
737 | up_write(&dcssblk_devices_sem); | |
93098bf0 HY |
738 | pr_warning("Device %s cannot be removed because it is not a " |
739 | "known device\n", local_buf); | |
1da177e4 LT |
740 | rc = -ENODEV; |
741 | goto out_buf; | |
742 | } | |
743 | if (atomic_read(&dev_info->use_count) != 0) { | |
744 | up_write(&dcssblk_devices_sem); | |
93098bf0 HY |
745 | pr_warning("Device %s cannot be removed while it is in " |
746 | "use\n", local_buf); | |
1da177e4 LT |
747 | rc = -EBUSY; |
748 | goto out_buf; | |
749 | } | |
1da177e4 | 750 | |
b2300b9e | 751 | list_del(&dev_info->lh); |
1da177e4 | 752 | del_gendisk(dev_info->gd); |
1312f40e | 753 | blk_cleanup_queue(dev_info->dcssblk_queue); |
1da177e4 LT |
754 | dev_info->gd->queue = NULL; |
755 | put_disk(dev_info->gd); | |
756 | device_unregister(&dev_info->dev); | |
b2300b9e HY |
757 | |
758 | /* unload all related segments */ | |
759 | list_for_each_entry(entry, &dev_info->seg_list, lh) | |
760 | segment_unload(entry->segment_name); | |
761 | ||
1da177e4 LT |
762 | put_device(&dev_info->dev); |
763 | up_write(&dcssblk_devices_sem); | |
764 | ||
765 | rc = count; | |
766 | out_buf: | |
767 | kfree(local_buf); | |
768 | return rc; | |
769 | } | |
770 | ||
771 | static int | |
46d74326 | 772 | dcssblk_open(struct block_device *bdev, fmode_t mode) |
1da177e4 LT |
773 | { |
774 | struct dcssblk_dev_info *dev_info; | |
775 | int rc; | |
776 | ||
46d74326 | 777 | dev_info = bdev->bd_disk->private_data; |
1da177e4 LT |
778 | if (NULL == dev_info) { |
779 | rc = -ENODEV; | |
780 | goto out; | |
781 | } | |
782 | atomic_inc(&dev_info->use_count); | |
46d74326 | 783 | bdev->bd_block_size = 4096; |
1da177e4 LT |
784 | rc = 0; |
785 | out: | |
786 | return rc; | |
787 | } | |
788 | ||
789 | static int | |
46d74326 | 790 | dcssblk_release(struct gendisk *disk, fmode_t mode) |
1da177e4 | 791 | { |
46d74326 | 792 | struct dcssblk_dev_info *dev_info = disk->private_data; |
b2300b9e | 793 | struct segment_info *entry; |
1da177e4 LT |
794 | int rc; |
795 | ||
46d74326 | 796 | if (!dev_info) { |
1da177e4 LT |
797 | rc = -ENODEV; |
798 | goto out; | |
799 | } | |
800 | down_write(&dcssblk_devices_sem); | |
801 | if (atomic_dec_and_test(&dev_info->use_count) | |
802 | && (dev_info->save_pending)) { | |
93098bf0 HY |
803 | pr_info("Device %s has become idle and is being saved " |
804 | "now\n", dev_info->segment_name); | |
b2300b9e HY |
805 | list_for_each_entry(entry, &dev_info->seg_list, lh) { |
806 | segment_save(entry->segment_name); | |
807 | } | |
1da177e4 LT |
808 | dev_info->save_pending = 0; |
809 | } | |
810 | up_write(&dcssblk_devices_sem); | |
811 | rc = 0; | |
812 | out: | |
813 | return rc; | |
814 | } | |
815 | ||
816 | static int | |
165125e1 | 817 | dcssblk_make_request(struct request_queue *q, struct bio *bio) |
1da177e4 LT |
818 | { |
819 | struct dcssblk_dev_info *dev_info; | |
820 | struct bio_vec *bvec; | |
821 | unsigned long index; | |
822 | unsigned long page_addr; | |
823 | unsigned long source_addr; | |
824 | unsigned long bytes_done; | |
825 | int i; | |
826 | ||
827 | bytes_done = 0; | |
828 | dev_info = bio->bi_bdev->bd_disk->private_data; | |
829 | if (dev_info == NULL) | |
830 | goto fail; | |
831 | if ((bio->bi_sector & 7) != 0 || (bio->bi_size & 4095) != 0) | |
832 | /* Request is not page-aligned. */ | |
833 | goto fail; | |
834 | if (((bio->bi_size >> 9) + bio->bi_sector) | |
835 | > get_capacity(bio->bi_bdev->bd_disk)) { | |
836 | /* Request beyond end of DCSS segment. */ | |
837 | goto fail; | |
838 | } | |
420edbcc CO |
839 | /* verify data transfer direction */ |
840 | if (dev_info->is_shared) { | |
841 | switch (dev_info->segment_type) { | |
842 | case SEG_TYPE_SR: | |
843 | case SEG_TYPE_ER: | |
844 | case SEG_TYPE_SC: | |
845 | /* cannot write to these segments */ | |
846 | if (bio_data_dir(bio) == WRITE) { | |
93098bf0 HY |
847 | pr_warning("Writing to %s failed because it " |
848 | "is a read-only device\n", | |
2a0217d5 | 849 | dev_name(&dev_info->dev)); |
420edbcc CO |
850 | goto fail; |
851 | } | |
852 | } | |
853 | } | |
854 | ||
1da177e4 LT |
855 | index = (bio->bi_sector >> 3); |
856 | bio_for_each_segment(bvec, bio, i) { | |
857 | page_addr = (unsigned long) | |
858 | page_address(bvec->bv_page) + bvec->bv_offset; | |
859 | source_addr = dev_info->start + (index<<12) + bytes_done; | |
39f73b28 | 860 | if (unlikely((page_addr & 4095) != 0) || (bvec->bv_len & 4095) != 0) |
1da177e4 LT |
861 | // More paranoia. |
862 | goto fail; | |
863 | if (bio_data_dir(bio) == READ) { | |
864 | memcpy((void*)page_addr, (void*)source_addr, | |
865 | bvec->bv_len); | |
866 | } else { | |
867 | memcpy((void*)source_addr, (void*)page_addr, | |
868 | bvec->bv_len); | |
869 | } | |
870 | bytes_done += bvec->bv_len; | |
871 | } | |
6712ecf8 | 872 | bio_endio(bio, 0); |
1da177e4 LT |
873 | return 0; |
874 | fail: | |
6712ecf8 | 875 | bio_io_error(bio); |
420edbcc CO |
876 | return 0; |
877 | } | |
878 | ||
879 | static int | |
880 | dcssblk_direct_access (struct block_device *bdev, sector_t secnum, | |
30afcb4b | 881 | void **kaddr, unsigned long *pfn) |
420edbcc CO |
882 | { |
883 | struct dcssblk_dev_info *dev_info; | |
884 | unsigned long pgoff; | |
885 | ||
886 | dev_info = bdev->bd_disk->private_data; | |
887 | if (!dev_info) | |
888 | return -ENODEV; | |
889 | if (secnum % (PAGE_SIZE/512)) | |
890 | return -EINVAL; | |
891 | pgoff = secnum / (PAGE_SIZE / 512); | |
892 | if ((pgoff+1)*PAGE_SIZE-1 > dev_info->end - dev_info->start) | |
893 | return -ERANGE; | |
30afcb4b JH |
894 | *kaddr = (void *) (dev_info->start+pgoff*PAGE_SIZE); |
895 | *pfn = virt_to_phys(*kaddr) >> PAGE_SHIFT; | |
896 | ||
1da177e4 LT |
897 | return 0; |
898 | } | |
899 | ||
900 | static void | |
901 | dcssblk_check_params(void) | |
902 | { | |
903 | int rc, i, j, k; | |
b2300b9e | 904 | char buf[DCSSBLK_PARM_LEN + 1]; |
1da177e4 LT |
905 | struct dcssblk_dev_info *dev_info; |
906 | ||
907 | for (i = 0; (i < DCSSBLK_PARM_LEN) && (dcssblk_segments[i] != '\0'); | |
908 | i++) { | |
909 | for (j = i; (dcssblk_segments[j] != ',') && | |
910 | (dcssblk_segments[j] != '\0') && | |
911 | (dcssblk_segments[j] != '(') && | |
b2300b9e | 912 | (j < DCSSBLK_PARM_LEN); j++) |
1da177e4 LT |
913 | { |
914 | buf[j-i] = dcssblk_segments[j]; | |
915 | } | |
916 | buf[j-i] = '\0'; | |
f901e5d1 | 917 | rc = dcssblk_add_store(dcssblk_root_dev, NULL, buf, j-i); |
1da177e4 | 918 | if ((rc >= 0) && (dcssblk_segments[j] == '(')) { |
b2300b9e | 919 | for (k = 0; (buf[k] != ':') && (buf[k] != '\0'); k++) |
1da177e4 | 920 | buf[k] = toupper(buf[k]); |
b2300b9e | 921 | buf[k] = '\0'; |
1da177e4 LT |
922 | if (!strncmp(&dcssblk_segments[j], "(local)", 7)) { |
923 | down_read(&dcssblk_devices_sem); | |
924 | dev_info = dcssblk_get_device_by_name(buf); | |
925 | up_read(&dcssblk_devices_sem); | |
926 | if (dev_info) | |
927 | dcssblk_shared_store(&dev_info->dev, | |
f901e5d1 | 928 | NULL, "0\n", 2); |
1da177e4 LT |
929 | } |
930 | } | |
931 | while ((dcssblk_segments[j] != ',') && | |
932 | (dcssblk_segments[j] != '\0')) | |
933 | { | |
934 | j++; | |
935 | } | |
936 | if (dcssblk_segments[j] == '\0') | |
937 | break; | |
938 | i = j; | |
939 | } | |
940 | } | |
941 | ||
942 | /* | |
943 | * The init/exit functions. | |
944 | */ | |
945 | static void __exit | |
946 | dcssblk_exit(void) | |
947 | { | |
035da16f | 948 | root_device_unregister(dcssblk_root_dev); |
00d59405 | 949 | unregister_blkdev(dcssblk_major, DCSSBLK_NAME); |
1da177e4 LT |
950 | } |
951 | ||
952 | static int __init | |
953 | dcssblk_init(void) | |
954 | { | |
955 | int rc; | |
956 | ||
035da16f | 957 | dcssblk_root_dev = root_device_register("dcssblk"); |
ded77fb4 | 958 | if (IS_ERR(dcssblk_root_dev)) |
1da177e4 | 959 | return PTR_ERR(dcssblk_root_dev); |
1da177e4 LT |
960 | rc = device_create_file(dcssblk_root_dev, &dev_attr_add); |
961 | if (rc) { | |
035da16f | 962 | root_device_unregister(dcssblk_root_dev); |
1da177e4 LT |
963 | return rc; |
964 | } | |
965 | rc = device_create_file(dcssblk_root_dev, &dev_attr_remove); | |
966 | if (rc) { | |
035da16f | 967 | root_device_unregister(dcssblk_root_dev); |
1da177e4 LT |
968 | return rc; |
969 | } | |
970 | rc = register_blkdev(0, DCSSBLK_NAME); | |
971 | if (rc < 0) { | |
035da16f | 972 | root_device_unregister(dcssblk_root_dev); |
1da177e4 LT |
973 | return rc; |
974 | } | |
975 | dcssblk_major = rc; | |
976 | init_rwsem(&dcssblk_devices_sem); | |
977 | ||
978 | dcssblk_check_params(); | |
979 | ||
1da177e4 LT |
980 | return 0; |
981 | } | |
982 | ||
983 | module_init(dcssblk_init); | |
984 | module_exit(dcssblk_exit); | |
985 | ||
986 | module_param_string(segments, dcssblk_segments, DCSSBLK_PARM_LEN, 0444); | |
987 | MODULE_PARM_DESC(segments, "Name of DCSS segment(s) to be loaded, " | |
b2300b9e HY |
988 | "comma-separated list, names in each set separated " |
989 | "by commas are separated by colons, each set contains " | |
990 | "names of contiguous segments and each name max. 8 chars.\n" | |
991 | "Adding \"(local)\" to the end of each set equals echoing 0 " | |
992 | "to /sys/devices/dcssblk/<device name>/shared after loading " | |
993 | "the contiguous segments - \n" | |
994 | "e.g. segments=\"mydcss1,mydcss2:mydcss3,mydcss4(local)\""); | |
1da177e4 LT |
995 | |
996 | MODULE_LICENSE("GPL"); |