2 * dcssblk.c -- the S/390 block driver for dcss memory
4 * Authors: Carsten Otte, Stefan Weinhuber, Gerald Schaefer
7 #define KMSG_COMPONENT "dcssblk"
8 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
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 <linux/completion.h>
18 #include <linux/interrupt.h>
19 #include <linux/platform_device.h>
20 #include <linux/pfn_t.h>
21 #include <linux/uio.h>
22 #include <linux/dax.h>
23 #include <asm/extmem.h>
26 #define DCSSBLK_NAME "dcssblk"
27 #define DCSSBLK_MINORS_PER_DISK 1
28 #define DCSSBLK_PARM_LEN 400
29 #define DCSS_BUS_ID_SIZE 20
31 static int dcssblk_open(struct block_device *bdev, fmode_t mode);
32 static void dcssblk_release(struct gendisk *disk, fmode_t mode);
33 static blk_qc_t dcssblk_make_request(struct request_queue *q,
35 static long dcssblk_dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff,
36 long nr_pages, void **kaddr, pfn_t *pfn);
38 static char dcssblk_segments[DCSSBLK_PARM_LEN] = "\0";
40 static int dcssblk_major;
41 static const struct block_device_operations dcssblk_devops = {
44 .release = dcssblk_release,
47 static size_t dcssblk_dax_copy_from_iter(struct dax_device *dax_dev,
48 pgoff_t pgoff, void *addr, size_t bytes, struct iov_iter *i)
50 return copy_from_iter(addr, bytes, i);
53 static const struct dax_operations dcssblk_dax_ops = {
54 .direct_access = dcssblk_dax_direct_access,
55 .copy_from_iter = dcssblk_dax_copy_from_iter,
58 struct dcssblk_dev_info {
61 char segment_name[DCSS_BUS_ID_SIZE];
67 unsigned char save_pending;
68 unsigned char is_shared;
69 struct request_queue *dcssblk_queue;
71 struct list_head seg_list;
72 struct dax_device *dax_dev;
77 char segment_name[DCSS_BUS_ID_SIZE];
83 static ssize_t dcssblk_add_store(struct device * dev, struct device_attribute *attr, const char * buf,
85 static ssize_t dcssblk_remove_store(struct device * dev, struct device_attribute *attr, const char * buf,
88 static DEVICE_ATTR(add, S_IWUSR, NULL, dcssblk_add_store);
89 static DEVICE_ATTR(remove, S_IWUSR, NULL, dcssblk_remove_store);
91 static struct device *dcssblk_root_dev;
93 static LIST_HEAD(dcssblk_devices);
94 static struct rw_semaphore dcssblk_devices_sem;
97 * release function for segment device.
100 dcssblk_release_segment(struct device *dev)
102 struct dcssblk_dev_info *dev_info;
103 struct segment_info *entry, *temp;
105 dev_info = container_of(dev, struct dcssblk_dev_info, dev);
106 list_for_each_entry_safe(entry, temp, &dev_info->seg_list, lh) {
107 list_del(&entry->lh);
111 module_put(THIS_MODULE);
115 * get a minor number. needs to be called with
116 * down_write(&dcssblk_devices_sem) and the
117 * device needs to be enqueued before the semaphore is
121 dcssblk_assign_free_minor(struct dcssblk_dev_info *dev_info)
124 struct dcssblk_dev_info *entry;
126 if (dev_info == NULL)
128 for (minor = 0; minor < (1<<MINORBITS); minor++) {
130 // test if minor available
131 list_for_each_entry(entry, &dcssblk_devices, lh)
132 if (minor == entry->gd->first_minor)
134 if (!found) break; // got unused minor
138 dev_info->gd->first_minor = minor;
143 * get the struct dcssblk_dev_info from dcssblk_devices
144 * for the given name.
145 * down_read(&dcssblk_devices_sem) must be held.
147 static struct dcssblk_dev_info *
148 dcssblk_get_device_by_name(char *name)
150 struct dcssblk_dev_info *entry;
152 list_for_each_entry(entry, &dcssblk_devices, lh) {
153 if (!strcmp(name, entry->segment_name)) {
161 * get the struct segment_info from seg_list
162 * for the given name.
163 * down_read(&dcssblk_devices_sem) must be held.
165 static struct segment_info *
166 dcssblk_get_segment_by_name(char *name)
168 struct dcssblk_dev_info *dev_info;
169 struct segment_info *entry;
171 list_for_each_entry(dev_info, &dcssblk_devices, lh) {
172 list_for_each_entry(entry, &dev_info->seg_list, lh) {
173 if (!strcmp(name, entry->segment_name))
181 * get the highest address of the multi-segment block.
184 dcssblk_find_highest_addr(struct dcssblk_dev_info *dev_info)
186 unsigned long highest_addr;
187 struct segment_info *entry;
190 list_for_each_entry(entry, &dev_info->seg_list, lh) {
191 if (highest_addr < entry->end)
192 highest_addr = entry->end;
198 * get the lowest address of the multi-segment block.
201 dcssblk_find_lowest_addr(struct dcssblk_dev_info *dev_info)
204 unsigned long lowest_addr;
205 struct segment_info *entry;
209 list_for_each_entry(entry, &dev_info->seg_list, lh) {
210 if (set_first == 0) {
211 lowest_addr = entry->start;
214 if (lowest_addr > entry->start)
215 lowest_addr = entry->start;
222 * Check continuity of segments.
225 dcssblk_is_continuous(struct dcssblk_dev_info *dev_info)
228 struct segment_info *sort_list, *entry, temp;
230 if (dev_info->num_of_segments <= 1)
234 sizeof(struct segment_info) * dev_info->num_of_segments,
236 if (sort_list == NULL)
239 list_for_each_entry(entry, &dev_info->seg_list, lh) {
240 memcpy(&sort_list[i], entry, sizeof(struct segment_info));
245 for (i = 0; i < dev_info->num_of_segments; i++)
246 for (j = 0; j < dev_info->num_of_segments; j++)
247 if (sort_list[j].start > sort_list[i].start) {
248 memcpy(&temp, &sort_list[i],
249 sizeof(struct segment_info));
250 memcpy(&sort_list[i], &sort_list[j],
251 sizeof(struct segment_info));
252 memcpy(&sort_list[j], &temp,
253 sizeof(struct segment_info));
256 /* check continuity */
257 for (i = 0; i < dev_info->num_of_segments - 1; i++) {
258 if ((sort_list[i].end + 1) != sort_list[i+1].start) {
259 pr_err("Adjacent DCSSs %s and %s are not "
260 "contiguous\n", sort_list[i].segment_name,
261 sort_list[i+1].segment_name);
265 /* EN and EW are allowed in a block device */
266 if (sort_list[i].segment_type != sort_list[i+1].segment_type) {
267 if (!(sort_list[i].segment_type & SEGMENT_EXCLUSIVE) ||
268 (sort_list[i].segment_type == SEG_TYPE_ER) ||
269 !(sort_list[i+1].segment_type &
270 SEGMENT_EXCLUSIVE) ||
271 (sort_list[i+1].segment_type == SEG_TYPE_ER)) {
272 pr_err("DCSS %s and DCSS %s have "
273 "incompatible types\n",
274 sort_list[i].segment_name,
275 sort_list[i+1].segment_name);
291 dcssblk_load_segment(char *name, struct segment_info **seg_info)
295 /* already loaded? */
296 down_read(&dcssblk_devices_sem);
297 *seg_info = dcssblk_get_segment_by_name(name);
298 up_read(&dcssblk_devices_sem);
299 if (*seg_info != NULL)
302 /* get a struct segment_info */
303 *seg_info = kzalloc(sizeof(struct segment_info), GFP_KERNEL);
304 if (*seg_info == NULL)
307 strcpy((*seg_info)->segment_name, name);
309 /* load the segment */
310 rc = segment_load(name, SEGMENT_SHARED,
311 &(*seg_info)->start, &(*seg_info)->end);
313 segment_warning(rc, (*seg_info)->segment_name);
316 INIT_LIST_HEAD(&(*seg_info)->lh);
317 (*seg_info)->segment_type = rc;
323 * device attribute for switching shared/nonshared (exclusive)
324 * operation (show + store)
327 dcssblk_shared_show(struct device *dev, struct device_attribute *attr, char *buf)
329 struct dcssblk_dev_info *dev_info;
331 dev_info = container_of(dev, struct dcssblk_dev_info, dev);
332 return sprintf(buf, dev_info->is_shared ? "1\n" : "0\n");
336 dcssblk_shared_store(struct device *dev, struct device_attribute *attr, const char *inbuf, size_t count)
338 struct dcssblk_dev_info *dev_info;
339 struct segment_info *entry, *temp;
342 if ((count > 1) && (inbuf[1] != '\n') && (inbuf[1] != '\0'))
344 down_write(&dcssblk_devices_sem);
345 dev_info = container_of(dev, struct dcssblk_dev_info, dev);
346 if (atomic_read(&dev_info->use_count)) {
350 if (inbuf[0] == '1') {
351 /* reload segments in shared mode */
352 list_for_each_entry(entry, &dev_info->seg_list, lh) {
353 rc = segment_modify_shared(entry->segment_name,
356 BUG_ON(rc == -EINVAL);
361 dev_info->is_shared = 1;
362 switch (dev_info->segment_type) {
366 set_disk_ro(dev_info->gd, 1);
368 } else if (inbuf[0] == '0') {
369 /* reload segments in exclusive mode */
370 if (dev_info->segment_type == SEG_TYPE_SC) {
371 pr_err("DCSS %s is of type SC and cannot be "
372 "loaded as exclusive-writable\n",
373 dev_info->segment_name);
377 list_for_each_entry(entry, &dev_info->seg_list, lh) {
378 rc = segment_modify_shared(entry->segment_name,
381 BUG_ON(rc == -EINVAL);
386 dev_info->is_shared = 0;
387 set_disk_ro(dev_info->gd, 0);
396 pr_err("DCSS device %s is removed after a failed access mode "
397 "change\n", dev_info->segment_name);
399 list_for_each_entry(entry, &dev_info->seg_list, lh) {
401 segment_unload(entry->segment_name);
403 list_del(&dev_info->lh);
405 kill_dax(dev_info->dax_dev);
406 put_dax(dev_info->dax_dev);
407 del_gendisk(dev_info->gd);
408 blk_cleanup_queue(dev_info->dcssblk_queue);
409 dev_info->gd->queue = NULL;
410 put_disk(dev_info->gd);
411 up_write(&dcssblk_devices_sem);
413 if (device_remove_file_self(dev, attr)) {
414 device_unregister(dev);
419 up_write(&dcssblk_devices_sem);
422 static DEVICE_ATTR(shared, S_IWUSR | S_IRUSR, dcssblk_shared_show,
423 dcssblk_shared_store);
426 * device attribute for save operation on current copy
427 * of the segment. If the segment is busy, saving will
428 * become pending until it gets released, which can be
429 * undone by storing a non-true value to this entry.
433 dcssblk_save_show(struct device *dev, struct device_attribute *attr, char *buf)
435 struct dcssblk_dev_info *dev_info;
437 dev_info = container_of(dev, struct dcssblk_dev_info, dev);
438 return sprintf(buf, dev_info->save_pending ? "1\n" : "0\n");
442 dcssblk_save_store(struct device *dev, struct device_attribute *attr, const char *inbuf, size_t count)
444 struct dcssblk_dev_info *dev_info;
445 struct segment_info *entry;
447 if ((count > 1) && (inbuf[1] != '\n') && (inbuf[1] != '\0'))
449 dev_info = container_of(dev, struct dcssblk_dev_info, dev);
451 down_write(&dcssblk_devices_sem);
452 if (inbuf[0] == '1') {
453 if (atomic_read(&dev_info->use_count) == 0) {
454 // device is idle => we save immediately
455 pr_info("All DCSSs that map to device %s are "
456 "saved\n", dev_info->segment_name);
457 list_for_each_entry(entry, &dev_info->seg_list, lh) {
458 if (entry->segment_type == SEG_TYPE_EN ||
459 entry->segment_type == SEG_TYPE_SN)
460 pr_warn("DCSS %s is of type SN or EN"
461 " and cannot be saved\n",
462 entry->segment_name);
464 segment_save(entry->segment_name);
467 // device is busy => we save it when it becomes
468 // idle in dcssblk_release
469 pr_info("Device %s is in use, its DCSSs will be "
470 "saved when it becomes idle\n",
471 dev_info->segment_name);
472 dev_info->save_pending = 1;
474 } else if (inbuf[0] == '0') {
475 if (dev_info->save_pending) {
476 // device is busy & the user wants to undo his save
478 dev_info->save_pending = 0;
479 pr_info("A pending save request for device %s "
480 "has been canceled\n",
481 dev_info->segment_name);
484 up_write(&dcssblk_devices_sem);
487 up_write(&dcssblk_devices_sem);
490 static DEVICE_ATTR(save, S_IWUSR | S_IRUSR, dcssblk_save_show,
494 * device attribute for showing all segments in a device
497 dcssblk_seglist_show(struct device *dev, struct device_attribute *attr,
502 struct dcssblk_dev_info *dev_info;
503 struct segment_info *entry;
505 down_read(&dcssblk_devices_sem);
506 dev_info = container_of(dev, struct dcssblk_dev_info, dev);
509 list_for_each_entry(entry, &dev_info->seg_list, lh) {
510 strcpy(&buf[i], entry->segment_name);
511 i += strlen(entry->segment_name);
515 up_read(&dcssblk_devices_sem);
518 static DEVICE_ATTR(seglist, S_IRUSR, dcssblk_seglist_show, NULL);
520 static struct attribute *dcssblk_dev_attrs[] = {
521 &dev_attr_shared.attr,
523 &dev_attr_seglist.attr,
526 static struct attribute_group dcssblk_dev_attr_group = {
527 .attrs = dcssblk_dev_attrs,
529 static const struct attribute_group *dcssblk_dev_attr_groups[] = {
530 &dcssblk_dev_attr_group,
535 * device attribute for adding devices
538 dcssblk_add_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
540 int rc, i, j, num_of_segments;
541 struct dcssblk_dev_info *dev_info;
542 struct segment_info *seg_info, *temp;
544 unsigned long seg_byte_size;
548 if (dev != dcssblk_root_dev) {
552 if ((count < 1) || (buf[0] == '\0') || (buf[0] == '\n')) {
557 local_buf = kmalloc(count + 1, GFP_KERNEL);
558 if (local_buf == NULL) {
567 for (i = 0; (i < count && (buf[i] != '\0') && (buf[i] != '\n')); i++) {
568 for (j = i; j < count &&
571 (buf[j] != '\n'); j++) {
572 local_buf[j-i] = toupper(buf[j]);
574 local_buf[j-i] = '\0';
575 if (((j - i) == 0) || ((j - i) > 8)) {
580 rc = dcssblk_load_segment(local_buf, &seg_info);
584 * get a struct dcssblk_dev_info
586 if (num_of_segments == 0) {
587 dev_info = kzalloc(sizeof(struct dcssblk_dev_info),
589 if (dev_info == NULL) {
593 strcpy(dev_info->segment_name, local_buf);
594 dev_info->segment_type = seg_info->segment_type;
595 INIT_LIST_HEAD(&dev_info->seg_list);
597 list_add_tail(&seg_info->lh, &dev_info->seg_list);
601 if ((buf[j] == '\0') || (buf[j] == '\n'))
605 /* no trailing colon at the end of the input */
606 if ((i > 0) && (buf[i-1] == ':')) {
610 strlcpy(local_buf, buf, i + 1);
611 dev_info->num_of_segments = num_of_segments;
612 rc = dcssblk_is_continuous(dev_info);
616 dev_info->start = dcssblk_find_lowest_addr(dev_info);
617 dev_info->end = dcssblk_find_highest_addr(dev_info);
619 dev_set_name(&dev_info->dev, "%s", dev_info->segment_name);
620 dev_info->dev.release = dcssblk_release_segment;
621 dev_info->dev.groups = dcssblk_dev_attr_groups;
622 INIT_LIST_HEAD(&dev_info->lh);
623 dev_info->gd = alloc_disk(DCSSBLK_MINORS_PER_DISK);
624 if (dev_info->gd == NULL) {
628 dev_info->gd->major = dcssblk_major;
629 dev_info->gd->fops = &dcssblk_devops;
630 dev_info->dcssblk_queue = blk_alloc_queue(GFP_KERNEL);
631 dev_info->gd->queue = dev_info->dcssblk_queue;
632 dev_info->gd->private_data = dev_info;
633 blk_queue_make_request(dev_info->dcssblk_queue, dcssblk_make_request);
634 blk_queue_logical_block_size(dev_info->dcssblk_queue, 4096);
635 queue_flag_set_unlocked(QUEUE_FLAG_DAX, dev_info->dcssblk_queue);
637 seg_byte_size = (dev_info->end - dev_info->start + 1);
638 set_capacity(dev_info->gd, seg_byte_size >> 9); // size in sectors
639 pr_info("Loaded %s with total size %lu bytes and capacity %lu "
640 "sectors\n", local_buf, seg_byte_size, seg_byte_size >> 9);
642 dev_info->save_pending = 0;
643 dev_info->is_shared = 1;
644 dev_info->dev.parent = dcssblk_root_dev;
647 *get minor, add to list
649 down_write(&dcssblk_devices_sem);
650 if (dcssblk_get_segment_by_name(local_buf)) {
654 rc = dcssblk_assign_free_minor(dev_info);
657 sprintf(dev_info->gd->disk_name, "dcssblk%d",
658 dev_info->gd->first_minor);
659 list_add_tail(&dev_info->lh, &dcssblk_devices);
661 if (!try_module_get(THIS_MODULE)) {
666 * register the device
668 rc = device_register(&dev_info->dev);
672 dev_info->dax_dev = alloc_dax(dev_info, dev_info->gd->disk_name,
674 if (!dev_info->dax_dev) {
679 get_device(&dev_info->dev);
680 device_add_disk(&dev_info->dev, dev_info->gd);
682 switch (dev_info->segment_type) {
686 set_disk_ro(dev_info->gd,1);
689 set_disk_ro(dev_info->gd,0);
692 up_write(&dcssblk_devices_sem);
697 list_del(&dev_info->lh);
698 blk_cleanup_queue(dev_info->dcssblk_queue);
699 dev_info->gd->queue = NULL;
700 put_disk(dev_info->gd);
701 list_for_each_entry(seg_info, &dev_info->seg_list, lh) {
702 segment_unload(seg_info->segment_name);
704 put_device(&dev_info->dev);
705 up_write(&dcssblk_devices_sem);
708 list_del(&dev_info->lh);
710 blk_cleanup_queue(dev_info->dcssblk_queue);
711 dev_info->gd->queue = NULL;
712 put_disk(dev_info->gd);
713 up_write(&dcssblk_devices_sem);
715 if (dev_info == NULL)
717 list_for_each_entry_safe(seg_info, temp, &dev_info->seg_list, lh) {
718 list_del(&seg_info->lh);
719 segment_unload(seg_info->segment_name);
730 * device attribute for removing devices
733 dcssblk_remove_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
735 struct dcssblk_dev_info *dev_info;
736 struct segment_info *entry;
740 if (dev != dcssblk_root_dev) {
743 local_buf = kmalloc(count + 1, GFP_KERNEL);
744 if (local_buf == NULL) {
750 for (i = 0; (i < count && (*(buf+i)!='\0') && (*(buf+i)!='\n')); i++) {
751 local_buf[i] = toupper(buf[i]);
754 if ((i == 0) || (i > 8)) {
759 down_write(&dcssblk_devices_sem);
760 dev_info = dcssblk_get_device_by_name(local_buf);
761 if (dev_info == NULL) {
762 up_write(&dcssblk_devices_sem);
763 pr_warn("Device %s cannot be removed because it is not a known device\n",
768 if (atomic_read(&dev_info->use_count) != 0) {
769 up_write(&dcssblk_devices_sem);
770 pr_warn("Device %s cannot be removed while it is in use\n",
776 list_del(&dev_info->lh);
777 kill_dax(dev_info->dax_dev);
778 put_dax(dev_info->dax_dev);
779 del_gendisk(dev_info->gd);
780 blk_cleanup_queue(dev_info->dcssblk_queue);
781 dev_info->gd->queue = NULL;
782 put_disk(dev_info->gd);
784 /* unload all related segments */
785 list_for_each_entry(entry, &dev_info->seg_list, lh)
786 segment_unload(entry->segment_name);
788 up_write(&dcssblk_devices_sem);
790 device_unregister(&dev_info->dev);
791 put_device(&dev_info->dev);
800 dcssblk_open(struct block_device *bdev, fmode_t mode)
802 struct dcssblk_dev_info *dev_info;
805 dev_info = bdev->bd_disk->private_data;
806 if (NULL == dev_info) {
810 atomic_inc(&dev_info->use_count);
811 bdev->bd_block_size = 4096;
818 dcssblk_release(struct gendisk *disk, fmode_t mode)
820 struct dcssblk_dev_info *dev_info = disk->private_data;
821 struct segment_info *entry;
827 down_write(&dcssblk_devices_sem);
828 if (atomic_dec_and_test(&dev_info->use_count)
829 && (dev_info->save_pending)) {
830 pr_info("Device %s has become idle and is being saved "
831 "now\n", dev_info->segment_name);
832 list_for_each_entry(entry, &dev_info->seg_list, lh) {
833 if (entry->segment_type == SEG_TYPE_EN ||
834 entry->segment_type == SEG_TYPE_SN)
835 pr_warn("DCSS %s is of type SN or EN and cannot"
836 " be saved\n", entry->segment_name);
838 segment_save(entry->segment_name);
840 dev_info->save_pending = 0;
842 up_write(&dcssblk_devices_sem);
846 dcssblk_make_request(struct request_queue *q, struct bio *bio)
848 struct dcssblk_dev_info *dev_info;
850 struct bvec_iter iter;
852 unsigned long page_addr;
853 unsigned long source_addr;
854 unsigned long bytes_done;
856 blk_queue_split(q, &bio);
859 dev_info = bio->bi_disk->private_data;
860 if (dev_info == NULL)
862 if ((bio->bi_iter.bi_sector & 7) != 0 ||
863 (bio->bi_iter.bi_size & 4095) != 0)
864 /* Request is not page-aligned. */
866 if (bio_end_sector(bio) > get_capacity(bio->bi_disk)) {
867 /* Request beyond end of DCSS segment. */
870 /* verify data transfer direction */
871 if (dev_info->is_shared) {
872 switch (dev_info->segment_type) {
876 /* cannot write to these segments */
877 if (bio_data_dir(bio) == WRITE) {
878 pr_warn("Writing to %s failed because it is a read-only device\n",
879 dev_name(&dev_info->dev));
885 index = (bio->bi_iter.bi_sector >> 3);
886 bio_for_each_segment(bvec, bio, iter) {
887 page_addr = (unsigned long)
888 page_address(bvec.bv_page) + bvec.bv_offset;
889 source_addr = dev_info->start + (index<<12) + bytes_done;
890 if (unlikely((page_addr & 4095) != 0) || (bvec.bv_len & 4095) != 0)
893 if (bio_data_dir(bio) == READ) {
894 memcpy((void*)page_addr, (void*)source_addr,
897 memcpy((void*)source_addr, (void*)page_addr,
900 bytes_done += bvec.bv_len;
903 return BLK_QC_T_NONE;
906 return BLK_QC_T_NONE;
910 __dcssblk_direct_access(struct dcssblk_dev_info *dev_info, pgoff_t pgoff,
911 long nr_pages, void **kaddr, pfn_t *pfn)
913 resource_size_t offset = pgoff * PAGE_SIZE;
914 unsigned long dev_sz;
916 dev_sz = dev_info->end - dev_info->start + 1;
917 *kaddr = (void *) dev_info->start + offset;
918 *pfn = __pfn_to_pfn_t(PFN_DOWN(dev_info->start + offset), PFN_DEV);
920 return (dev_sz - offset) / PAGE_SIZE;
924 dcssblk_dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff,
925 long nr_pages, void **kaddr, pfn_t *pfn)
927 struct dcssblk_dev_info *dev_info = dax_get_private(dax_dev);
929 return __dcssblk_direct_access(dev_info, pgoff, nr_pages, kaddr, pfn);
933 dcssblk_check_params(void)
936 char buf[DCSSBLK_PARM_LEN + 1];
937 struct dcssblk_dev_info *dev_info;
939 for (i = 0; (i < DCSSBLK_PARM_LEN) && (dcssblk_segments[i] != '\0');
941 for (j = i; (j < DCSSBLK_PARM_LEN) &&
942 (dcssblk_segments[j] != ',') &&
943 (dcssblk_segments[j] != '\0') &&
944 (dcssblk_segments[j] != '('); j++)
946 buf[j-i] = dcssblk_segments[j];
949 rc = dcssblk_add_store(dcssblk_root_dev, NULL, buf, j-i);
950 if ((rc >= 0) && (dcssblk_segments[j] == '(')) {
951 for (k = 0; (buf[k] != ':') && (buf[k] != '\0'); k++)
952 buf[k] = toupper(buf[k]);
954 if (!strncmp(&dcssblk_segments[j], "(local)", 7)) {
955 down_read(&dcssblk_devices_sem);
956 dev_info = dcssblk_get_device_by_name(buf);
957 up_read(&dcssblk_devices_sem);
959 dcssblk_shared_store(&dev_info->dev,
963 while ((dcssblk_segments[j] != ',') &&
964 (dcssblk_segments[j] != '\0'))
968 if (dcssblk_segments[j] == '\0')
977 static int dcssblk_freeze(struct device *dev)
979 struct dcssblk_dev_info *dev_info;
982 list_for_each_entry(dev_info, &dcssblk_devices, lh) {
983 switch (dev_info->segment_type) {
987 if (!dev_info->is_shared)
998 pr_err("Suspending the system failed because DCSS device %s "
1000 dev_info->segment_name);
1004 static int dcssblk_restore(struct device *dev)
1006 struct dcssblk_dev_info *dev_info;
1007 struct segment_info *entry;
1008 unsigned long start, end;
1011 list_for_each_entry(dev_info, &dcssblk_devices, lh) {
1012 list_for_each_entry(entry, &dev_info->seg_list, lh) {
1013 segment_unload(entry->segment_name);
1014 rc = segment_load(entry->segment_name, SEGMENT_SHARED,
1017 // TODO in_use check ?
1018 segment_warning(rc, entry->segment_name);
1021 if (start != entry->start || end != entry->end) {
1022 pr_err("The address range of DCSS %s changed "
1023 "while the system was suspended\n",
1024 entry->segment_name);
1031 panic("fatal dcssblk resume error\n");
1034 static int dcssblk_thaw(struct device *dev)
1039 static const struct dev_pm_ops dcssblk_pm_ops = {
1040 .freeze = dcssblk_freeze,
1041 .thaw = dcssblk_thaw,
1042 .restore = dcssblk_restore,
1045 static struct platform_driver dcssblk_pdrv = {
1048 .pm = &dcssblk_pm_ops,
1052 static struct platform_device *dcssblk_pdev;
1056 * The init/exit functions.
1061 platform_device_unregister(dcssblk_pdev);
1062 platform_driver_unregister(&dcssblk_pdrv);
1063 root_device_unregister(dcssblk_root_dev);
1064 unregister_blkdev(dcssblk_major, DCSSBLK_NAME);
1072 rc = platform_driver_register(&dcssblk_pdrv);
1076 dcssblk_pdev = platform_device_register_simple("dcssblk", -1, NULL,
1078 if (IS_ERR(dcssblk_pdev)) {
1079 rc = PTR_ERR(dcssblk_pdev);
1083 dcssblk_root_dev = root_device_register("dcssblk");
1084 if (IS_ERR(dcssblk_root_dev)) {
1085 rc = PTR_ERR(dcssblk_root_dev);
1088 rc = device_create_file(dcssblk_root_dev, &dev_attr_add);
1091 rc = device_create_file(dcssblk_root_dev, &dev_attr_remove);
1094 rc = register_blkdev(0, DCSSBLK_NAME);
1098 init_rwsem(&dcssblk_devices_sem);
1100 dcssblk_check_params();
1104 root_device_unregister(dcssblk_root_dev);
1106 platform_device_unregister(dcssblk_pdev);
1108 platform_driver_unregister(&dcssblk_pdrv);
1112 module_init(dcssblk_init);
1113 module_exit(dcssblk_exit);
1115 module_param_string(segments, dcssblk_segments, DCSSBLK_PARM_LEN, 0444);
1116 MODULE_PARM_DESC(segments, "Name of DCSS segment(s) to be loaded, "
1117 "comma-separated list, names in each set separated "
1118 "by commas are separated by colons, each set contains "
1119 "names of contiguous segments and each name max. 8 chars.\n"
1120 "Adding \"(local)\" to the end of each set equals echoing 0 "
1121 "to /sys/devices/dcssblk/<device name>/shared after loading "
1122 "the contiguous segments - \n"
1123 "e.g. segments=\"mydcss1,mydcss2:mydcss3,mydcss4(local)\"");
1125 MODULE_LICENSE("GPL");