blob: 2c5a397b9f3e7e7ac71519aaeb5d51758f33371f [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * dcssblk.c -- the S/390 block driver for dcss memory
3 *
4 * Authors: Carsten Otte, Stefan Weinhuber, Gerald Schaefer
5 */
6
Hongjie Yang93098bf2008-12-25 13:39:45 +01007#define KMSG_COMPONENT "dcssblk"
8#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
9
Linus Torvalds1da177e2005-04-16 15:20:36 -070010#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>
Linus Torvalds1da177e2005-04-16 15:20:36 -070017#include <linux/completion.h>
18#include <linux/interrupt.h>
Gerald Schaeferc3695272009-06-16 10:30:51 +020019#include <linux/platform_device.h>
20#include <asm/extmem.h>
21#include <asm/io.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070022
Linus Torvalds1da177e2005-04-16 15:20:36 -070023#define DCSSBLK_NAME "dcssblk"
24#define DCSSBLK_MINORS_PER_DISK 1
25#define DCSSBLK_PARM_LEN 400
Kay Sievers98df67b2008-12-25 13:38:55 +010026#define DCSS_BUS_ID_SIZE 20
Linus Torvalds1da177e2005-04-16 15:20:36 -070027
Al Viro46d74322008-03-02 10:37:41 -050028static int dcssblk_open(struct block_device *bdev, fmode_t mode);
Al Virodb2a1442013-05-05 21:52:57 -040029static void dcssblk_release(struct gendisk *disk, fmode_t mode);
Christoph Hellwig5a7bbad2011-09-12 12:12:01 +020030static void dcssblk_make_request(struct request_queue *q, struct bio *bio);
Matthew Wilcoxdd22f552015-01-07 18:05:34 +020031static long dcssblk_direct_access(struct block_device *bdev, sector_t secnum,
Ross Zwislere2e05392015-08-18 13:55:41 -060032 void __pmem **kaddr, unsigned long *pfn, long size);
Linus Torvalds1da177e2005-04-16 15:20:36 -070033
34static char dcssblk_segments[DCSSBLK_PARM_LEN] = "\0";
35
36static int dcssblk_major;
Alexey Dobriyan83d5cde2009-09-21 17:01:13 -070037static const struct block_device_operations dcssblk_devops = {
Carsten Otte420edbc2005-06-23 22:05:23 -070038 .owner = THIS_MODULE,
Al Viro46d74322008-03-02 10:37:41 -050039 .open = dcssblk_open,
40 .release = dcssblk_release,
Carsten Otte420edbc2005-06-23 22:05:23 -070041 .direct_access = dcssblk_direct_access,
Linus Torvalds1da177e2005-04-16 15:20:36 -070042};
43
Linus Torvalds1da177e2005-04-16 15:20:36 -070044struct dcssblk_dev_info {
45 struct list_head lh;
46 struct device dev;
Kay Sievers98df67b2008-12-25 13:38:55 +010047 char segment_name[DCSS_BUS_ID_SIZE];
Linus Torvalds1da177e2005-04-16 15:20:36 -070048 atomic_t use_count;
49 struct gendisk *gd;
50 unsigned long start;
51 unsigned long end;
52 int segment_type;
53 unsigned char save_pending;
54 unsigned char is_shared;
55 struct request_queue *dcssblk_queue;
Hongjie Yangb2300b92008-10-10 21:33:21 +020056 int num_of_segments;
57 struct list_head seg_list;
Linus Torvalds1da177e2005-04-16 15:20:36 -070058};
59
Hongjie Yangb2300b92008-10-10 21:33:21 +020060struct segment_info {
61 struct list_head lh;
Kay Sievers98df67b2008-12-25 13:38:55 +010062 char segment_name[DCSS_BUS_ID_SIZE];
Hongjie Yangb2300b92008-10-10 21:33:21 +020063 unsigned long start;
64 unsigned long end;
65 int segment_type;
66};
67
68static ssize_t dcssblk_add_store(struct device * dev, struct device_attribute *attr, const char * buf,
69 size_t count);
70static ssize_t dcssblk_remove_store(struct device * dev, struct device_attribute *attr, const char * buf,
71 size_t count);
Hongjie Yangb2300b92008-10-10 21:33:21 +020072
73static DEVICE_ATTR(add, S_IWUSR, NULL, dcssblk_add_store);
74static DEVICE_ATTR(remove, S_IWUSR, NULL, dcssblk_remove_store);
Hongjie Yangb2300b92008-10-10 21:33:21 +020075
76static struct device *dcssblk_root_dev;
77
Denis Chengc11ca972008-01-26 14:11:13 +010078static LIST_HEAD(dcssblk_devices);
Linus Torvalds1da177e2005-04-16 15:20:36 -070079static struct rw_semaphore dcssblk_devices_sem;
80
81/*
82 * release function for segment device.
83 */
84static void
85dcssblk_release_segment(struct device *dev)
86{
Hongjie Yangb2300b92008-10-10 21:33:21 +020087 struct dcssblk_dev_info *dev_info;
88 struct segment_info *entry, *temp;
89
90 dev_info = container_of(dev, struct dcssblk_dev_info, dev);
91 list_for_each_entry_safe(entry, temp, &dev_info->seg_list, lh) {
92 list_del(&entry->lh);
93 kfree(entry);
94 }
95 kfree(dev_info);
Linus Torvalds1da177e2005-04-16 15:20:36 -070096 module_put(THIS_MODULE);
97}
98
99/*
100 * get a minor number. needs to be called with
101 * down_write(&dcssblk_devices_sem) and the
102 * device needs to be enqueued before the semaphore is
103 * freed.
104 */
Heiko Carstens4d284ca2007-02-05 21:18:53 +0100105static int
Linus Torvalds1da177e2005-04-16 15:20:36 -0700106dcssblk_assign_free_minor(struct dcssblk_dev_info *dev_info)
107{
108 int minor, found;
109 struct dcssblk_dev_info *entry;
110
111 if (dev_info == NULL)
112 return -EINVAL;
113 for (minor = 0; minor < (1<<MINORBITS); minor++) {
114 found = 0;
115 // test if minor available
116 list_for_each_entry(entry, &dcssblk_devices, lh)
Gerald Schaeferd0591482009-06-12 10:26:35 +0200117 if (minor == entry->gd->first_minor)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700118 found++;
119 if (!found) break; // got unused minor
120 }
121 if (found)
122 return -EBUSY;
123 dev_info->gd->first_minor = minor;
124 return 0;
125}
126
127/*
128 * get the struct dcssblk_dev_info from dcssblk_devices
129 * for the given name.
130 * down_read(&dcssblk_devices_sem) must be held.
131 */
132static struct dcssblk_dev_info *
133dcssblk_get_device_by_name(char *name)
134{
135 struct dcssblk_dev_info *entry;
136
137 list_for_each_entry(entry, &dcssblk_devices, lh) {
138 if (!strcmp(name, entry->segment_name)) {
139 return entry;
140 }
141 }
142 return NULL;
143}
144
Hongjie Yangb2300b92008-10-10 21:33:21 +0200145/*
146 * get the struct segment_info from seg_list
147 * for the given name.
148 * down_read(&dcssblk_devices_sem) must be held.
149 */
150static struct segment_info *
151dcssblk_get_segment_by_name(char *name)
152{
153 struct dcssblk_dev_info *dev_info;
154 struct segment_info *entry;
155
156 list_for_each_entry(dev_info, &dcssblk_devices, lh) {
157 list_for_each_entry(entry, &dev_info->seg_list, lh) {
158 if (!strcmp(name, entry->segment_name))
159 return entry;
160 }
161 }
162 return NULL;
163}
164
165/*
166 * get the highest address of the multi-segment block.
167 */
168static unsigned long
169dcssblk_find_highest_addr(struct dcssblk_dev_info *dev_info)
170{
171 unsigned long highest_addr;
172 struct segment_info *entry;
173
174 highest_addr = 0;
175 list_for_each_entry(entry, &dev_info->seg_list, lh) {
176 if (highest_addr < entry->end)
177 highest_addr = entry->end;
178 }
179 return highest_addr;
180}
181
182/*
183 * get the lowest address of the multi-segment block.
184 */
185static unsigned long
186dcssblk_find_lowest_addr(struct dcssblk_dev_info *dev_info)
187{
188 int set_first;
189 unsigned long lowest_addr;
190 struct segment_info *entry;
191
192 set_first = 0;
193 lowest_addr = 0;
194 list_for_each_entry(entry, &dev_info->seg_list, lh) {
195 if (set_first == 0) {
196 lowest_addr = entry->start;
197 set_first = 1;
198 } else {
199 if (lowest_addr > entry->start)
200 lowest_addr = entry->start;
201 }
202 }
203 return lowest_addr;
204}
205
206/*
207 * Check continuity of segments.
208 */
209static int
210dcssblk_is_continuous(struct dcssblk_dev_info *dev_info)
211{
212 int i, j, rc;
213 struct segment_info *sort_list, *entry, temp;
214
215 if (dev_info->num_of_segments <= 1)
216 return 0;
217
218 sort_list = kzalloc(
219 sizeof(struct segment_info) * dev_info->num_of_segments,
220 GFP_KERNEL);
221 if (sort_list == NULL)
222 return -ENOMEM;
223 i = 0;
224 list_for_each_entry(entry, &dev_info->seg_list, lh) {
225 memcpy(&sort_list[i], entry, sizeof(struct segment_info));
226 i++;
227 }
228
229 /* sort segments */
230 for (i = 0; i < dev_info->num_of_segments; i++)
231 for (j = 0; j < dev_info->num_of_segments; j++)
232 if (sort_list[j].start > sort_list[i].start) {
233 memcpy(&temp, &sort_list[i],
234 sizeof(struct segment_info));
235 memcpy(&sort_list[i], &sort_list[j],
236 sizeof(struct segment_info));
237 memcpy(&sort_list[j], &temp,
238 sizeof(struct segment_info));
239 }
240
241 /* check continuity */
242 for (i = 0; i < dev_info->num_of_segments - 1; i++) {
243 if ((sort_list[i].end + 1) != sort_list[i+1].start) {
Hongjie Yang93098bf2008-12-25 13:39:45 +0100244 pr_err("Adjacent DCSSs %s and %s are not "
245 "contiguous\n", sort_list[i].segment_name,
246 sort_list[i+1].segment_name);
Hongjie Yangb2300b92008-10-10 21:33:21 +0200247 rc = -EINVAL;
248 goto out;
249 }
250 /* EN and EW are allowed in a block device */
251 if (sort_list[i].segment_type != sort_list[i+1].segment_type) {
252 if (!(sort_list[i].segment_type & SEGMENT_EXCLUSIVE) ||
253 (sort_list[i].segment_type == SEG_TYPE_ER) ||
254 !(sort_list[i+1].segment_type &
255 SEGMENT_EXCLUSIVE) ||
256 (sort_list[i+1].segment_type == SEG_TYPE_ER)) {
Hongjie Yang93098bf2008-12-25 13:39:45 +0100257 pr_err("DCSS %s and DCSS %s have "
258 "incompatible types\n",
259 sort_list[i].segment_name,
260 sort_list[i+1].segment_name);
Hongjie Yangb2300b92008-10-10 21:33:21 +0200261 rc = -EINVAL;
262 goto out;
263 }
264 }
265 }
266 rc = 0;
267out:
268 kfree(sort_list);
269 return rc;
270}
271
272/*
273 * Load a segment
274 */
275static int
276dcssblk_load_segment(char *name, struct segment_info **seg_info)
277{
278 int rc;
279
280 /* already loaded? */
281 down_read(&dcssblk_devices_sem);
282 *seg_info = dcssblk_get_segment_by_name(name);
283 up_read(&dcssblk_devices_sem);
284 if (*seg_info != NULL)
285 return -EEXIST;
286
287 /* get a struct segment_info */
288 *seg_info = kzalloc(sizeof(struct segment_info), GFP_KERNEL);
289 if (*seg_info == NULL)
290 return -ENOMEM;
291
292 strcpy((*seg_info)->segment_name, name);
293
294 /* load the segment */
295 rc = segment_load(name, SEGMENT_SHARED,
296 &(*seg_info)->start, &(*seg_info)->end);
297 if (rc < 0) {
298 segment_warning(rc, (*seg_info)->segment_name);
299 kfree(*seg_info);
300 } else {
301 INIT_LIST_HEAD(&(*seg_info)->lh);
302 (*seg_info)->segment_type = rc;
303 }
304 return rc;
305}
306
Linus Torvalds1da177e2005-04-16 15:20:36 -0700307/*
308 * device attribute for switching shared/nonshared (exclusive)
309 * operation (show + store)
310 */
311static ssize_t
Yani Ioannoue404e272005-05-17 06:42:58 -0400312dcssblk_shared_show(struct device *dev, struct device_attribute *attr, char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700313{
314 struct dcssblk_dev_info *dev_info;
315
316 dev_info = container_of(dev, struct dcssblk_dev_info, dev);
317 return sprintf(buf, dev_info->is_shared ? "1\n" : "0\n");
318}
319
320static ssize_t
Yani Ioannoue404e272005-05-17 06:42:58 -0400321dcssblk_shared_store(struct device *dev, struct device_attribute *attr, const char *inbuf, size_t count)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700322{
323 struct dcssblk_dev_info *dev_info;
Hongjie Yangb2300b92008-10-10 21:33:21 +0200324 struct segment_info *entry, *temp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700325 int rc;
326
Hongjie Yangded77fb2008-07-14 09:59:39 +0200327 if ((count > 1) && (inbuf[1] != '\n') && (inbuf[1] != '\0'))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700328 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700329 down_write(&dcssblk_devices_sem);
330 dev_info = container_of(dev, struct dcssblk_dev_info, dev);
331 if (atomic_read(&dev_info->use_count)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700332 rc = -EBUSY;
333 goto out;
334 }
335 if (inbuf[0] == '1') {
Hongjie Yangb2300b92008-10-10 21:33:21 +0200336 /* reload segments in shared mode */
337 list_for_each_entry(entry, &dev_info->seg_list, lh) {
338 rc = segment_modify_shared(entry->segment_name,
339 SEGMENT_SHARED);
340 if (rc < 0) {
341 BUG_ON(rc == -EINVAL);
342 if (rc != -EAGAIN)
343 goto removeseg;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700344 }
345 }
Hongjie Yangb2300b92008-10-10 21:33:21 +0200346 dev_info->is_shared = 1;
347 switch (dev_info->segment_type) {
348 case SEG_TYPE_SR:
349 case SEG_TYPE_ER:
350 case SEG_TYPE_SC:
351 set_disk_ro(dev_info->gd, 1);
352 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700353 } else if (inbuf[0] == '0') {
Hongjie Yangb2300b92008-10-10 21:33:21 +0200354 /* reload segments in exclusive mode */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700355 if (dev_info->segment_type == SEG_TYPE_SC) {
Hongjie Yang93098bf2008-12-25 13:39:45 +0100356 pr_err("DCSS %s is of type SC and cannot be "
357 "loaded as exclusive-writable\n",
358 dev_info->segment_name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700359 rc = -EINVAL;
360 goto out;
361 }
Hongjie Yangb2300b92008-10-10 21:33:21 +0200362 list_for_each_entry(entry, &dev_info->seg_list, lh) {
363 rc = segment_modify_shared(entry->segment_name,
364 SEGMENT_EXCLUSIVE);
365 if (rc < 0) {
366 BUG_ON(rc == -EINVAL);
367 if (rc != -EAGAIN)
368 goto removeseg;
369 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700370 }
Hongjie Yangb2300b92008-10-10 21:33:21 +0200371 dev_info->is_shared = 0;
372 set_disk_ro(dev_info->gd, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700373 } else {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700374 rc = -EINVAL;
375 goto out;
376 }
377 rc = count;
378 goto out;
379
380removeseg:
Hongjie Yang93098bf2008-12-25 13:39:45 +0100381 pr_err("DCSS device %s is removed after a failed access mode "
382 "change\n", dev_info->segment_name);
Hongjie Yangb2300b92008-10-10 21:33:21 +0200383 temp = entry;
384 list_for_each_entry(entry, &dev_info->seg_list, lh) {
385 if (entry != temp)
386 segment_unload(entry->segment_name);
387 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700388 list_del(&dev_info->lh);
389
390 del_gendisk(dev_info->gd);
Al Viro1312f402006-03-12 11:02:03 -0500391 blk_cleanup_queue(dev_info->dcssblk_queue);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700392 dev_info->gd->queue = NULL;
393 put_disk(dev_info->gd);
Tejun Heo0b60f9e2014-02-03 14:03:04 -0500394 up_write(&dcssblk_devices_sem);
395
396 if (device_remove_file_self(dev, attr)) {
397 device_unregister(dev);
398 put_device(dev);
399 }
400 return rc;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700401out:
402 up_write(&dcssblk_devices_sem);
403 return rc;
404}
Sebastian Ott521b3d72012-10-01 09:12:01 +0200405static DEVICE_ATTR(shared, S_IWUSR | S_IRUSR, dcssblk_shared_show,
406 dcssblk_shared_store);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700407
408/*
409 * device attribute for save operation on current copy
410 * of the segment. If the segment is busy, saving will
411 * become pending until it gets released, which can be
412 * undone by storing a non-true value to this entry.
413 * (show + store)
414 */
415static ssize_t
Yani Ioannoue404e272005-05-17 06:42:58 -0400416dcssblk_save_show(struct device *dev, struct device_attribute *attr, char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700417{
418 struct dcssblk_dev_info *dev_info;
419
420 dev_info = container_of(dev, struct dcssblk_dev_info, dev);
421 return sprintf(buf, dev_info->save_pending ? "1\n" : "0\n");
422}
423
424static ssize_t
Yani Ioannoue404e272005-05-17 06:42:58 -0400425dcssblk_save_store(struct device *dev, struct device_attribute *attr, const char *inbuf, size_t count)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700426{
427 struct dcssblk_dev_info *dev_info;
Hongjie Yangb2300b92008-10-10 21:33:21 +0200428 struct segment_info *entry;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700429
Hongjie Yangded77fb2008-07-14 09:59:39 +0200430 if ((count > 1) && (inbuf[1] != '\n') && (inbuf[1] != '\0'))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700431 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700432 dev_info = container_of(dev, struct dcssblk_dev_info, dev);
433
434 down_write(&dcssblk_devices_sem);
435 if (inbuf[0] == '1') {
436 if (atomic_read(&dev_info->use_count) == 0) {
437 // device is idle => we save immediately
Hongjie Yang93098bf2008-12-25 13:39:45 +0100438 pr_info("All DCSSs that map to device %s are "
439 "saved\n", dev_info->segment_name);
Hongjie Yangb2300b92008-10-10 21:33:21 +0200440 list_for_each_entry(entry, &dev_info->seg_list, lh) {
Gerald Schaefer5be6fdc2015-01-16 18:29:04 +0100441 if (entry->segment_type == SEG_TYPE_EN ||
442 entry->segment_type == SEG_TYPE_SN)
443 pr_warn("DCSS %s is of type SN or EN"
444 " and cannot be saved\n",
445 entry->segment_name);
446 else
447 segment_save(entry->segment_name);
Hongjie Yangb2300b92008-10-10 21:33:21 +0200448 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700449 } else {
450 // device is busy => we save it when it becomes
451 // idle in dcssblk_release
Hongjie Yang93098bf2008-12-25 13:39:45 +0100452 pr_info("Device %s is in use, its DCSSs will be "
453 "saved when it becomes idle\n",
454 dev_info->segment_name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700455 dev_info->save_pending = 1;
456 }
457 } else if (inbuf[0] == '0') {
458 if (dev_info->save_pending) {
459 // device is busy & the user wants to undo his save
460 // request
461 dev_info->save_pending = 0;
Hongjie Yang93098bf2008-12-25 13:39:45 +0100462 pr_info("A pending save request for device %s "
463 "has been canceled\n",
464 dev_info->segment_name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700465 }
466 } else {
467 up_write(&dcssblk_devices_sem);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700468 return -EINVAL;
469 }
470 up_write(&dcssblk_devices_sem);
471 return count;
472}
Sebastian Ott521b3d72012-10-01 09:12:01 +0200473static DEVICE_ATTR(save, S_IWUSR | S_IRUSR, dcssblk_save_show,
474 dcssblk_save_store);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700475
476/*
Hongjie Yangb2300b92008-10-10 21:33:21 +0200477 * device attribute for showing all segments in a device
478 */
479static ssize_t
480dcssblk_seglist_show(struct device *dev, struct device_attribute *attr,
481 char *buf)
482{
483 int i;
484
485 struct dcssblk_dev_info *dev_info;
486 struct segment_info *entry;
487
488 down_read(&dcssblk_devices_sem);
489 dev_info = container_of(dev, struct dcssblk_dev_info, dev);
490 i = 0;
491 buf[0] = '\0';
492 list_for_each_entry(entry, &dev_info->seg_list, lh) {
493 strcpy(&buf[i], entry->segment_name);
494 i += strlen(entry->segment_name);
495 buf[i] = '\n';
496 i++;
497 }
498 up_read(&dcssblk_devices_sem);
499 return i;
500}
Sebastian Ott521b3d72012-10-01 09:12:01 +0200501static DEVICE_ATTR(seglist, S_IRUSR, dcssblk_seglist_show, NULL);
502
503static struct attribute *dcssblk_dev_attrs[] = {
504 &dev_attr_shared.attr,
505 &dev_attr_save.attr,
506 &dev_attr_seglist.attr,
507 NULL,
508};
509static struct attribute_group dcssblk_dev_attr_group = {
510 .attrs = dcssblk_dev_attrs,
511};
512static const struct attribute_group *dcssblk_dev_attr_groups[] = {
513 &dcssblk_dev_attr_group,
514 NULL,
515};
Hongjie Yangb2300b92008-10-10 21:33:21 +0200516
517/*
Linus Torvalds1da177e2005-04-16 15:20:36 -0700518 * device attribute for adding devices
519 */
520static ssize_t
Yani Ioannoue404e272005-05-17 06:42:58 -0400521dcssblk_add_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700522{
Hongjie Yangb2300b92008-10-10 21:33:21 +0200523 int rc, i, j, num_of_segments;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700524 struct dcssblk_dev_info *dev_info;
Hongjie Yangb2300b92008-10-10 21:33:21 +0200525 struct segment_info *seg_info, *temp;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700526 char *local_buf;
527 unsigned long seg_byte_size;
528
529 dev_info = NULL;
Hongjie Yangb2300b92008-10-10 21:33:21 +0200530 seg_info = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700531 if (dev != dcssblk_root_dev) {
532 rc = -EINVAL;
533 goto out_nobuf;
534 }
Hongjie Yangb2300b92008-10-10 21:33:21 +0200535 if ((count < 1) || (buf[0] == '\0') || (buf[0] == '\n')) {
536 rc = -ENAMETOOLONG;
537 goto out_nobuf;
538 }
539
Linus Torvalds1da177e2005-04-16 15:20:36 -0700540 local_buf = kmalloc(count + 1, GFP_KERNEL);
541 if (local_buf == NULL) {
542 rc = -ENOMEM;
543 goto out_nobuf;
544 }
Hongjie Yangb2300b92008-10-10 21:33:21 +0200545
Linus Torvalds1da177e2005-04-16 15:20:36 -0700546 /*
547 * parse input
548 */
Hongjie Yangb2300b92008-10-10 21:33:21 +0200549 num_of_segments = 0;
Ameen Ali3a9f9182015-02-24 18:41:50 +0200550 for (i = 0; (i < count && (buf[i] != '\0') && (buf[i] != '\n')); i++) {
Hongjie Yangb2300b92008-10-10 21:33:21 +0200551 for (j = i; (buf[j] != ':') &&
552 (buf[j] != '\0') &&
553 (buf[j] != '\n') &&
554 j < count; j++) {
555 local_buf[j-i] = toupper(buf[j]);
556 }
557 local_buf[j-i] = '\0';
558 if (((j - i) == 0) || ((j - i) > 8)) {
559 rc = -ENAMETOOLONG;
560 goto seg_list_del;
561 }
562
563 rc = dcssblk_load_segment(local_buf, &seg_info);
564 if (rc < 0)
565 goto seg_list_del;
566 /*
567 * get a struct dcssblk_dev_info
568 */
569 if (num_of_segments == 0) {
570 dev_info = kzalloc(sizeof(struct dcssblk_dev_info),
571 GFP_KERNEL);
572 if (dev_info == NULL) {
573 rc = -ENOMEM;
574 goto out;
575 }
576 strcpy(dev_info->segment_name, local_buf);
577 dev_info->segment_type = seg_info->segment_type;
578 INIT_LIST_HEAD(&dev_info->seg_list);
579 }
580 list_add_tail(&seg_info->lh, &dev_info->seg_list);
581 num_of_segments++;
582 i = j;
583
584 if ((buf[j] == '\0') || (buf[j] == '\n'))
585 break;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700586 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700587
Hongjie Yangb2300b92008-10-10 21:33:21 +0200588 /* no trailing colon at the end of the input */
589 if ((i > 0) && (buf[i-1] == ':')) {
590 rc = -ENAMETOOLONG;
591 goto seg_list_del;
592 }
593 strlcpy(local_buf, buf, i + 1);
594 dev_info->num_of_segments = num_of_segments;
595 rc = dcssblk_is_continuous(dev_info);
596 if (rc < 0)
597 goto seg_list_del;
598
599 dev_info->start = dcssblk_find_lowest_addr(dev_info);
600 dev_info->end = dcssblk_find_highest_addr(dev_info);
601
Kees Cookef283688f2014-06-10 10:46:20 -0700602 dev_set_name(&dev_info->dev, "%s", dev_info->segment_name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700603 dev_info->dev.release = dcssblk_release_segment;
Sebastian Ott521b3d72012-10-01 09:12:01 +0200604 dev_info->dev.groups = dcssblk_dev_attr_groups;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700605 INIT_LIST_HEAD(&dev_info->lh);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700606 dev_info->gd = alloc_disk(DCSSBLK_MINORS_PER_DISK);
607 if (dev_info->gd == NULL) {
608 rc = -ENOMEM;
Hongjie Yangb2300b92008-10-10 21:33:21 +0200609 goto seg_list_del;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700610 }
611 dev_info->gd->major = dcssblk_major;
612 dev_info->gd->fops = &dcssblk_devops;
613 dev_info->dcssblk_queue = blk_alloc_queue(GFP_KERNEL);
614 dev_info->gd->queue = dev_info->dcssblk_queue;
615 dev_info->gd->private_data = dev_info;
616 dev_info->gd->driverfs_dev = &dev_info->dev;
Heiko Carstensc5411db2008-02-05 16:50:50 +0100617 blk_queue_make_request(dev_info->dcssblk_queue, dcssblk_make_request);
Martin K. Petersene1defc42009-05-22 17:17:49 -0400618 blk_queue_logical_block_size(dev_info->dcssblk_queue, 4096);
Hongjie Yangb2300b92008-10-10 21:33:21 +0200619
Linus Torvalds1da177e2005-04-16 15:20:36 -0700620 seg_byte_size = (dev_info->end - dev_info->start + 1);
621 set_capacity(dev_info->gd, seg_byte_size >> 9); // size in sectors
Hongjie Yang93098bf2008-12-25 13:39:45 +0100622 pr_info("Loaded %s with total size %lu bytes and capacity %lu "
623 "sectors\n", local_buf, seg_byte_size, seg_byte_size >> 9);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700624
Linus Torvalds1da177e2005-04-16 15:20:36 -0700625 dev_info->save_pending = 0;
626 dev_info->is_shared = 1;
627 dev_info->dev.parent = dcssblk_root_dev;
628
629 /*
Hongjie Yangb2300b92008-10-10 21:33:21 +0200630 *get minor, add to list
Linus Torvalds1da177e2005-04-16 15:20:36 -0700631 */
632 down_write(&dcssblk_devices_sem);
Hongjie Yangb2300b92008-10-10 21:33:21 +0200633 if (dcssblk_get_segment_by_name(local_buf)) {
Gerald Schaefer04f64b52008-08-21 19:46:40 +0200634 rc = -EEXIST;
Hongjie Yangb2300b92008-10-10 21:33:21 +0200635 goto release_gd;
Gerald Schaefer04f64b52008-08-21 19:46:40 +0200636 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700637 rc = dcssblk_assign_free_minor(dev_info);
Hongjie Yangb2300b92008-10-10 21:33:21 +0200638 if (rc)
639 goto release_gd;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700640 sprintf(dev_info->gd->disk_name, "dcssblk%d",
Gerald Schaeferd0591482009-06-12 10:26:35 +0200641 dev_info->gd->first_minor);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700642 list_add_tail(&dev_info->lh, &dcssblk_devices);
643
644 if (!try_module_get(THIS_MODULE)) {
645 rc = -ENODEV;
Hongjie Yangb2300b92008-10-10 21:33:21 +0200646 goto dev_list_del;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700647 }
648 /*
649 * register the device
650 */
651 rc = device_register(&dev_info->dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700652 if (rc)
Sebastian Ott521b3d72012-10-01 09:12:01 +0200653 goto put_dev;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700654
Sebastian Ott521b3d72012-10-01 09:12:01 +0200655 get_device(&dev_info->dev);
Christian Borntraeger436d1bc2007-12-04 16:09:03 +0100656 add_disk(dev_info->gd);
657
Linus Torvalds1da177e2005-04-16 15:20:36 -0700658 switch (dev_info->segment_type) {
659 case SEG_TYPE_SR:
660 case SEG_TYPE_ER:
661 case SEG_TYPE_SC:
662 set_disk_ro(dev_info->gd,1);
663 break;
664 default:
665 set_disk_ro(dev_info->gd,0);
666 break;
667 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700668 up_write(&dcssblk_devices_sem);
669 rc = count;
670 goto out;
671
Sebastian Ott521b3d72012-10-01 09:12:01 +0200672put_dev:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700673 list_del(&dev_info->lh);
Al Viro1312f402006-03-12 11:02:03 -0500674 blk_cleanup_queue(dev_info->dcssblk_queue);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700675 dev_info->gd->queue = NULL;
676 put_disk(dev_info->gd);
Hongjie Yangb2300b92008-10-10 21:33:21 +0200677 list_for_each_entry(seg_info, &dev_info->seg_list, lh) {
678 segment_unload(seg_info->segment_name);
679 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700680 put_device(&dev_info->dev);
681 up_write(&dcssblk_devices_sem);
682 goto out;
Hongjie Yangb2300b92008-10-10 21:33:21 +0200683dev_list_del:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700684 list_del(&dev_info->lh);
Hongjie Yangb2300b92008-10-10 21:33:21 +0200685release_gd:
Al Viro1312f402006-03-12 11:02:03 -0500686 blk_cleanup_queue(dev_info->dcssblk_queue);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700687 dev_info->gd->queue = NULL;
688 put_disk(dev_info->gd);
Hongjie Yangb2300b92008-10-10 21:33:21 +0200689 up_write(&dcssblk_devices_sem);
690seg_list_del:
691 if (dev_info == NULL)
692 goto out;
693 list_for_each_entry_safe(seg_info, temp, &dev_info->seg_list, lh) {
694 list_del(&seg_info->lh);
695 segment_unload(seg_info->segment_name);
696 kfree(seg_info);
697 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700698 kfree(dev_info);
699out:
700 kfree(local_buf);
701out_nobuf:
702 return rc;
703}
704
705/*
706 * device attribute for removing devices
707 */
708static ssize_t
Yani Ioannoue404e272005-05-17 06:42:58 -0400709dcssblk_remove_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700710{
711 struct dcssblk_dev_info *dev_info;
Hongjie Yangb2300b92008-10-10 21:33:21 +0200712 struct segment_info *entry;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700713 int rc, i;
714 char *local_buf;
715
716 if (dev != dcssblk_root_dev) {
717 return -EINVAL;
718 }
719 local_buf = kmalloc(count + 1, GFP_KERNEL);
720 if (local_buf == NULL) {
721 return -ENOMEM;
722 }
723 /*
724 * parse input
725 */
726 for (i = 0; ((*(buf+i)!='\0') && (*(buf+i)!='\n') && i < count); i++) {
727 local_buf[i] = toupper(buf[i]);
728 }
729 local_buf[i] = '\0';
730 if ((i == 0) || (i > 8)) {
731 rc = -ENAMETOOLONG;
732 goto out_buf;
733 }
734
735 down_write(&dcssblk_devices_sem);
736 dev_info = dcssblk_get_device_by_name(local_buf);
737 if (dev_info == NULL) {
738 up_write(&dcssblk_devices_sem);
Hongjie Yang93098bf2008-12-25 13:39:45 +0100739 pr_warning("Device %s cannot be removed because it is not a "
740 "known device\n", local_buf);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700741 rc = -ENODEV;
742 goto out_buf;
743 }
744 if (atomic_read(&dev_info->use_count) != 0) {
745 up_write(&dcssblk_devices_sem);
Hongjie Yang93098bf2008-12-25 13:39:45 +0100746 pr_warning("Device %s cannot be removed while it is in "
747 "use\n", local_buf);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700748 rc = -EBUSY;
749 goto out_buf;
750 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700751
Hongjie Yangb2300b92008-10-10 21:33:21 +0200752 list_del(&dev_info->lh);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700753 del_gendisk(dev_info->gd);
Al Viro1312f402006-03-12 11:02:03 -0500754 blk_cleanup_queue(dev_info->dcssblk_queue);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700755 dev_info->gd->queue = NULL;
756 put_disk(dev_info->gd);
757 device_unregister(&dev_info->dev);
Hongjie Yangb2300b92008-10-10 21:33:21 +0200758
759 /* unload all related segments */
760 list_for_each_entry(entry, &dev_info->seg_list, lh)
761 segment_unload(entry->segment_name);
762
Linus Torvalds1da177e2005-04-16 15:20:36 -0700763 put_device(&dev_info->dev);
764 up_write(&dcssblk_devices_sem);
765
766 rc = count;
767out_buf:
768 kfree(local_buf);
769 return rc;
770}
771
772static int
Al Viro46d74322008-03-02 10:37:41 -0500773dcssblk_open(struct block_device *bdev, fmode_t mode)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700774{
775 struct dcssblk_dev_info *dev_info;
776 int rc;
777
Al Viro46d74322008-03-02 10:37:41 -0500778 dev_info = bdev->bd_disk->private_data;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700779 if (NULL == dev_info) {
780 rc = -ENODEV;
781 goto out;
782 }
783 atomic_inc(&dev_info->use_count);
Al Viro46d74322008-03-02 10:37:41 -0500784 bdev->bd_block_size = 4096;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700785 rc = 0;
786out:
787 return rc;
788}
789
Al Virodb2a1442013-05-05 21:52:57 -0400790static void
Al Viro46d74322008-03-02 10:37:41 -0500791dcssblk_release(struct gendisk *disk, fmode_t mode)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700792{
Al Viro46d74322008-03-02 10:37:41 -0500793 struct dcssblk_dev_info *dev_info = disk->private_data;
Hongjie Yangb2300b92008-10-10 21:33:21 +0200794 struct segment_info *entry;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700795
Al Viro46d74322008-03-02 10:37:41 -0500796 if (!dev_info) {
Al Virodb2a1442013-05-05 21:52:57 -0400797 WARN_ON(1);
798 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700799 }
800 down_write(&dcssblk_devices_sem);
801 if (atomic_dec_and_test(&dev_info->use_count)
802 && (dev_info->save_pending)) {
Hongjie Yang93098bf2008-12-25 13:39:45 +0100803 pr_info("Device %s has become idle and is being saved "
804 "now\n", dev_info->segment_name);
Hongjie Yangb2300b92008-10-10 21:33:21 +0200805 list_for_each_entry(entry, &dev_info->seg_list, lh) {
Gerald Schaefer5be6fdc2015-01-16 18:29:04 +0100806 if (entry->segment_type == SEG_TYPE_EN ||
807 entry->segment_type == SEG_TYPE_SN)
808 pr_warn("DCSS %s is of type SN or EN and cannot"
809 " be saved\n", entry->segment_name);
810 else
811 segment_save(entry->segment_name);
Hongjie Yangb2300b92008-10-10 21:33:21 +0200812 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700813 dev_info->save_pending = 0;
814 }
815 up_write(&dcssblk_devices_sem);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700816}
817
Christoph Hellwig5a7bbad2011-09-12 12:12:01 +0200818static void
Jens Axboe165125e2007-07-24 09:28:11 +0200819dcssblk_make_request(struct request_queue *q, struct bio *bio)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700820{
821 struct dcssblk_dev_info *dev_info;
Kent Overstreet79886132013-11-23 17:19:00 -0800822 struct bio_vec bvec;
823 struct bvec_iter iter;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700824 unsigned long index;
825 unsigned long page_addr;
826 unsigned long source_addr;
827 unsigned long bytes_done;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700828
829 bytes_done = 0;
830 dev_info = bio->bi_bdev->bd_disk->private_data;
831 if (dev_info == NULL)
832 goto fail;
Kent Overstreet4f024f32013-10-11 15:44:27 -0700833 if ((bio->bi_iter.bi_sector & 7) != 0 ||
834 (bio->bi_iter.bi_size & 4095) != 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700835 /* Request is not page-aligned. */
836 goto fail;
Kent Overstreetf73a1c72012-09-25 15:05:12 -0700837 if (bio_end_sector(bio) > get_capacity(bio->bi_bdev->bd_disk)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700838 /* Request beyond end of DCSS segment. */
839 goto fail;
840 }
Carsten Otte420edbc2005-06-23 22:05:23 -0700841 /* verify data transfer direction */
842 if (dev_info->is_shared) {
843 switch (dev_info->segment_type) {
844 case SEG_TYPE_SR:
845 case SEG_TYPE_ER:
846 case SEG_TYPE_SC:
847 /* cannot write to these segments */
848 if (bio_data_dir(bio) == WRITE) {
Hongjie Yang93098bf2008-12-25 13:39:45 +0100849 pr_warning("Writing to %s failed because it "
850 "is a read-only device\n",
Kay Sievers2a0217d2008-10-10 21:33:09 +0200851 dev_name(&dev_info->dev));
Carsten Otte420edbc2005-06-23 22:05:23 -0700852 goto fail;
853 }
854 }
855 }
856
Kent Overstreet4f024f32013-10-11 15:44:27 -0700857 index = (bio->bi_iter.bi_sector >> 3);
Kent Overstreet79886132013-11-23 17:19:00 -0800858 bio_for_each_segment(bvec, bio, iter) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700859 page_addr = (unsigned long)
Kent Overstreet79886132013-11-23 17:19:00 -0800860 page_address(bvec.bv_page) + bvec.bv_offset;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700861 source_addr = dev_info->start + (index<<12) + bytes_done;
Kent Overstreet79886132013-11-23 17:19:00 -0800862 if (unlikely((page_addr & 4095) != 0) || (bvec.bv_len & 4095) != 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700863 // More paranoia.
864 goto fail;
865 if (bio_data_dir(bio) == READ) {
866 memcpy((void*)page_addr, (void*)source_addr,
Kent Overstreet79886132013-11-23 17:19:00 -0800867 bvec.bv_len);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700868 } else {
869 memcpy((void*)source_addr, (void*)page_addr,
Kent Overstreet79886132013-11-23 17:19:00 -0800870 bvec.bv_len);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700871 }
Kent Overstreet79886132013-11-23 17:19:00 -0800872 bytes_done += bvec.bv_len;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700873 }
NeilBrown6712ecf2007-09-27 12:47:43 +0200874 bio_endio(bio, 0);
Christoph Hellwig5a7bbad2011-09-12 12:12:01 +0200875 return;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700876fail:
NeilBrown6712ecf2007-09-27 12:47:43 +0200877 bio_io_error(bio);
Carsten Otte420edbc2005-06-23 22:05:23 -0700878}
879
Matthew Wilcoxdd22f552015-01-07 18:05:34 +0200880static long
Carsten Otte420edbc2005-06-23 22:05:23 -0700881dcssblk_direct_access (struct block_device *bdev, sector_t secnum,
Ross Zwislere2e05392015-08-18 13:55:41 -0600882 void __pmem **kaddr, unsigned long *pfn, long size)
Carsten Otte420edbc2005-06-23 22:05:23 -0700883{
884 struct dcssblk_dev_info *dev_info;
Matthew Wilcoxdd22f552015-01-07 18:05:34 +0200885 unsigned long offset, dev_sz;
Ross Zwislere2e05392015-08-18 13:55:41 -0600886 void *addr;
Carsten Otte420edbc2005-06-23 22:05:23 -0700887
888 dev_info = bdev->bd_disk->private_data;
889 if (!dev_info)
890 return -ENODEV;
Matthew Wilcoxdd22f552015-01-07 18:05:34 +0200891 dev_sz = dev_info->end - dev_info->start;
892 offset = secnum * 512;
Ross Zwislere2e05392015-08-18 13:55:41 -0600893 addr = (void *) (dev_info->start + offset);
894 *pfn = virt_to_phys(addr) >> PAGE_SHIFT;
895 *kaddr = (void __pmem *) addr;
Jared Hulbert30afcb42008-04-28 02:13:02 -0700896
Matthew Wilcoxdd22f552015-01-07 18:05:34 +0200897 return dev_sz - offset;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700898}
899
900static void
901dcssblk_check_params(void)
902{
903 int rc, i, j, k;
Hongjie Yangb2300b92008-10-10 21:33:21 +0200904 char buf[DCSSBLK_PARM_LEN + 1];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700905 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] != '(') &&
Hongjie Yangb2300b92008-10-10 21:33:21 +0200912 (j < DCSSBLK_PARM_LEN); j++)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700913 {
914 buf[j-i] = dcssblk_segments[j];
915 }
916 buf[j-i] = '\0';
Cornelia Huckf901e5d12005-06-25 14:55:29 -0700917 rc = dcssblk_add_store(dcssblk_root_dev, NULL, buf, j-i);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700918 if ((rc >= 0) && (dcssblk_segments[j] == '(')) {
Hongjie Yangb2300b92008-10-10 21:33:21 +0200919 for (k = 0; (buf[k] != ':') && (buf[k] != '\0'); k++)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700920 buf[k] = toupper(buf[k]);
Hongjie Yangb2300b92008-10-10 21:33:21 +0200921 buf[k] = '\0';
Linus Torvalds1da177e2005-04-16 15:20:36 -0700922 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,
Cornelia Huckf901e5d12005-06-25 14:55:29 -0700928 NULL, "0\n", 2);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700929 }
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/*
Gerald Schaeferc3695272009-06-16 10:30:51 +0200943 * Suspend / Resume
944 */
945static int dcssblk_freeze(struct device *dev)
946{
947 struct dcssblk_dev_info *dev_info;
948 int rc = 0;
949
950 list_for_each_entry(dev_info, &dcssblk_devices, lh) {
951 switch (dev_info->segment_type) {
952 case SEG_TYPE_SR:
953 case SEG_TYPE_ER:
954 case SEG_TYPE_SC:
955 if (!dev_info->is_shared)
956 rc = -EINVAL;
957 break;
958 default:
959 rc = -EINVAL;
960 break;
961 }
962 if (rc)
963 break;
964 }
965 if (rc)
Christian Borntraeger2c48c4d2009-07-07 16:37:11 +0200966 pr_err("Suspending the system failed because DCSS device %s "
967 "is writable\n",
Gerald Schaeferc3695272009-06-16 10:30:51 +0200968 dev_info->segment_name);
969 return rc;
970}
971
972static int dcssblk_restore(struct device *dev)
973{
974 struct dcssblk_dev_info *dev_info;
975 struct segment_info *entry;
976 unsigned long start, end;
977 int rc = 0;
978
979 list_for_each_entry(dev_info, &dcssblk_devices, lh) {
980 list_for_each_entry(entry, &dev_info->seg_list, lh) {
981 segment_unload(entry->segment_name);
982 rc = segment_load(entry->segment_name, SEGMENT_SHARED,
983 &start, &end);
984 if (rc < 0) {
985// TODO in_use check ?
986 segment_warning(rc, entry->segment_name);
987 goto out_panic;
988 }
989 if (start != entry->start || end != entry->end) {
Christian Borntraeger2c48c4d2009-07-07 16:37:11 +0200990 pr_err("The address range of DCSS %s changed "
991 "while the system was suspended\n",
Gerald Schaeferc3695272009-06-16 10:30:51 +0200992 entry->segment_name);
993 goto out_panic;
994 }
995 }
996 }
997 return 0;
998out_panic:
999 panic("fatal dcssblk resume error\n");
1000}
1001
1002static int dcssblk_thaw(struct device *dev)
1003{
1004 return 0;
1005}
1006
Alexey Dobriyan47145212009-12-14 18:00:08 -08001007static const struct dev_pm_ops dcssblk_pm_ops = {
Gerald Schaeferc3695272009-06-16 10:30:51 +02001008 .freeze = dcssblk_freeze,
1009 .thaw = dcssblk_thaw,
1010 .restore = dcssblk_restore,
1011};
1012
1013static struct platform_driver dcssblk_pdrv = {
1014 .driver = {
1015 .name = "dcssblk",
Gerald Schaeferc3695272009-06-16 10:30:51 +02001016 .pm = &dcssblk_pm_ops,
1017 },
1018};
1019
1020static struct platform_device *dcssblk_pdev;
1021
1022
1023/*
Linus Torvalds1da177e2005-04-16 15:20:36 -07001024 * The init/exit functions.
1025 */
1026static void __exit
1027dcssblk_exit(void)
1028{
Gerald Schaeferc3695272009-06-16 10:30:51 +02001029 platform_device_unregister(dcssblk_pdev);
1030 platform_driver_unregister(&dcssblk_pdrv);
Mark McLoughlin035da162008-12-15 12:58:29 +00001031 root_device_unregister(dcssblk_root_dev);
Akinobu Mita00d59402007-07-17 04:03:46 -07001032 unregister_blkdev(dcssblk_major, DCSSBLK_NAME);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001033}
1034
1035static int __init
1036dcssblk_init(void)
1037{
1038 int rc;
1039
Gerald Schaeferc3695272009-06-16 10:30:51 +02001040 rc = platform_driver_register(&dcssblk_pdrv);
1041 if (rc)
1042 return rc;
1043
1044 dcssblk_pdev = platform_device_register_simple("dcssblk", -1, NULL,
1045 0);
1046 if (IS_ERR(dcssblk_pdev)) {
1047 rc = PTR_ERR(dcssblk_pdev);
1048 goto out_pdrv;
1049 }
1050
Mark McLoughlin035da162008-12-15 12:58:29 +00001051 dcssblk_root_dev = root_device_register("dcssblk");
Gerald Schaeferc3695272009-06-16 10:30:51 +02001052 if (IS_ERR(dcssblk_root_dev)) {
1053 rc = PTR_ERR(dcssblk_root_dev);
1054 goto out_pdev;
1055 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001056 rc = device_create_file(dcssblk_root_dev, &dev_attr_add);
Gerald Schaeferc3695272009-06-16 10:30:51 +02001057 if (rc)
1058 goto out_root;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001059 rc = device_create_file(dcssblk_root_dev, &dev_attr_remove);
Gerald Schaeferc3695272009-06-16 10:30:51 +02001060 if (rc)
1061 goto out_root;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001062 rc = register_blkdev(0, DCSSBLK_NAME);
Gerald Schaeferc3695272009-06-16 10:30:51 +02001063 if (rc < 0)
1064 goto out_root;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001065 dcssblk_major = rc;
1066 init_rwsem(&dcssblk_devices_sem);
1067
1068 dcssblk_check_params();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001069 return 0;
Gerald Schaeferc3695272009-06-16 10:30:51 +02001070
1071out_root:
1072 root_device_unregister(dcssblk_root_dev);
1073out_pdev:
1074 platform_device_unregister(dcssblk_pdev);
1075out_pdrv:
1076 platform_driver_unregister(&dcssblk_pdrv);
1077 return rc;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001078}
1079
1080module_init(dcssblk_init);
1081module_exit(dcssblk_exit);
1082
1083module_param_string(segments, dcssblk_segments, DCSSBLK_PARM_LEN, 0444);
1084MODULE_PARM_DESC(segments, "Name of DCSS segment(s) to be loaded, "
Hongjie Yangb2300b92008-10-10 21:33:21 +02001085 "comma-separated list, names in each set separated "
1086 "by commas are separated by colons, each set contains "
1087 "names of contiguous segments and each name max. 8 chars.\n"
1088 "Adding \"(local)\" to the end of each set equals echoing 0 "
1089 "to /sys/devices/dcssblk/<device name>/shared after loading "
1090 "the contiguous segments - \n"
1091 "e.g. segments=\"mydcss1,mydcss2:mydcss3,mydcss4(local)\"");
Linus Torvalds1da177e2005-04-16 15:20:36 -07001092
1093MODULE_LICENSE("GPL");