Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * gendisk handling | |
3 | */ | |
4 | ||
5 | #include <linux/config.h> | |
6 | #include <linux/module.h> | |
7 | #include <linux/fs.h> | |
8 | #include <linux/genhd.h> | |
9 | #include <linux/kernel.h> | |
10 | #include <linux/blkdev.h> | |
11 | #include <linux/init.h> | |
12 | #include <linux/spinlock.h> | |
13 | #include <linux/seq_file.h> | |
14 | #include <linux/slab.h> | |
15 | #include <linux/kmod.h> | |
16 | #include <linux/kobj_map.h> | |
2ef41634 | 17 | #include <linux/buffer_head.h> |
1da177e4 LT |
18 | |
19 | #define MAX_PROBE_HASH 255 /* random */ | |
20 | ||
21 | static struct subsystem block_subsys; | |
22 | ||
23 | static DECLARE_MUTEX(block_subsys_sem); | |
24 | ||
25 | /* | |
26 | * Can be deleted altogether. Later. | |
27 | * | |
28 | */ | |
29 | static struct blk_major_name { | |
30 | struct blk_major_name *next; | |
31 | int major; | |
32 | char name[16]; | |
33 | } *major_names[MAX_PROBE_HASH]; | |
34 | ||
35 | /* index in the above - for now: assume no multimajor ranges */ | |
36 | static inline int major_to_index(int major) | |
37 | { | |
38 | return major % MAX_PROBE_HASH; | |
39 | } | |
40 | ||
7170be5f NH |
41 | struct blkdev_info { |
42 | int index; | |
43 | struct blk_major_name *bd; | |
44 | }; | |
45 | ||
46 | /* | |
47 | * iterate over a list of blkdev_info structures. allows | |
48 | * the major_names array to be iterated over from outside this file | |
49 | * must be called with the block_subsys_sem held | |
50 | */ | |
51 | void *get_next_blkdev(void *dev) | |
52 | { | |
53 | struct blkdev_info *info; | |
54 | ||
55 | if (dev == NULL) { | |
56 | info = kmalloc(sizeof(*info), GFP_KERNEL); | |
57 | if (!info) | |
58 | goto out; | |
59 | info->index=0; | |
60 | info->bd = major_names[info->index]; | |
61 | if (info->bd) | |
62 | goto out; | |
63 | } else { | |
64 | info = dev; | |
65 | } | |
66 | ||
67 | while (info->index < ARRAY_SIZE(major_names)) { | |
68 | if (info->bd) | |
69 | info->bd = info->bd->next; | |
70 | if (info->bd) | |
71 | goto out; | |
72 | /* | |
73 | * No devices on this chain, move to the next | |
74 | */ | |
75 | info->index++; | |
76 | info->bd = (info->index < ARRAY_SIZE(major_names)) ? | |
77 | major_names[info->index] : NULL; | |
78 | if (info->bd) | |
79 | goto out; | |
80 | } | |
81 | ||
82 | out: | |
83 | return info; | |
84 | } | |
85 | ||
86 | void *acquire_blkdev_list(void) | |
87 | { | |
88 | down(&block_subsys_sem); | |
89 | return get_next_blkdev(NULL); | |
90 | } | |
91 | ||
92 | void release_blkdev_list(void *dev) | |
93 | { | |
94 | up(&block_subsys_sem); | |
95 | kfree(dev); | |
96 | } | |
97 | ||
98 | ||
99 | /* | |
100 | * Count the number of records in the blkdev_list. | |
101 | * must be called with the block_subsys_sem held | |
102 | */ | |
103 | int count_blkdev_list(void) | |
1da177e4 LT |
104 | { |
105 | struct blk_major_name *n; | |
7170be5f | 106 | int i, count; |
1da177e4 | 107 | |
7170be5f | 108 | count = 0; |
1da177e4 | 109 | |
1da177e4 | 110 | for (i = 0; i < ARRAY_SIZE(major_names); i++) { |
7170be5f NH |
111 | for (n = major_names[i]; n; n = n->next) |
112 | count++; | |
1da177e4 | 113 | } |
1da177e4 | 114 | |
7170be5f NH |
115 | return count; |
116 | } | |
117 | ||
118 | /* | |
119 | * extract the major and name values from a blkdev_info struct | |
120 | * passed in as a void to *dev. Must be called with | |
121 | * block_subsys_sem held | |
122 | */ | |
123 | int get_blkdev_info(void *dev, int *major, char **name) | |
124 | { | |
125 | struct blkdev_info *info = dev; | |
126 | ||
127 | if (info->bd == NULL) | |
128 | return 1; | |
129 | ||
130 | *major = info->bd->major; | |
131 | *name = info->bd->name; | |
132 | return 0; | |
1da177e4 | 133 | } |
7170be5f | 134 | |
1da177e4 LT |
135 | |
136 | int register_blkdev(unsigned int major, const char *name) | |
137 | { | |
138 | struct blk_major_name **n, *p; | |
139 | int index, ret = 0; | |
140 | ||
141 | down(&block_subsys_sem); | |
142 | ||
143 | /* temporary */ | |
144 | if (major == 0) { | |
145 | for (index = ARRAY_SIZE(major_names)-1; index > 0; index--) { | |
146 | if (major_names[index] == NULL) | |
147 | break; | |
148 | } | |
149 | ||
150 | if (index == 0) { | |
151 | printk("register_blkdev: failed to get major for %s\n", | |
152 | name); | |
153 | ret = -EBUSY; | |
154 | goto out; | |
155 | } | |
156 | major = index; | |
157 | ret = major; | |
158 | } | |
159 | ||
160 | p = kmalloc(sizeof(struct blk_major_name), GFP_KERNEL); | |
161 | if (p == NULL) { | |
162 | ret = -ENOMEM; | |
163 | goto out; | |
164 | } | |
165 | ||
166 | p->major = major; | |
167 | strlcpy(p->name, name, sizeof(p->name)); | |
168 | p->next = NULL; | |
169 | index = major_to_index(major); | |
170 | ||
171 | for (n = &major_names[index]; *n; n = &(*n)->next) { | |
172 | if ((*n)->major == major) | |
173 | break; | |
174 | } | |
175 | if (!*n) | |
176 | *n = p; | |
177 | else | |
178 | ret = -EBUSY; | |
179 | ||
180 | if (ret < 0) { | |
181 | printk("register_blkdev: cannot get major %d for %s\n", | |
182 | major, name); | |
183 | kfree(p); | |
184 | } | |
185 | out: | |
186 | up(&block_subsys_sem); | |
187 | return ret; | |
188 | } | |
189 | ||
190 | EXPORT_SYMBOL(register_blkdev); | |
191 | ||
192 | /* todo: make void - error printk here */ | |
193 | int unregister_blkdev(unsigned int major, const char *name) | |
194 | { | |
195 | struct blk_major_name **n; | |
196 | struct blk_major_name *p = NULL; | |
197 | int index = major_to_index(major); | |
198 | int ret = 0; | |
199 | ||
200 | down(&block_subsys_sem); | |
201 | for (n = &major_names[index]; *n; n = &(*n)->next) | |
202 | if ((*n)->major == major) | |
203 | break; | |
204 | if (!*n || strcmp((*n)->name, name)) | |
205 | ret = -EINVAL; | |
206 | else { | |
207 | p = *n; | |
208 | *n = p->next; | |
209 | } | |
210 | up(&block_subsys_sem); | |
211 | kfree(p); | |
212 | ||
213 | return ret; | |
214 | } | |
215 | ||
216 | EXPORT_SYMBOL(unregister_blkdev); | |
217 | ||
218 | static struct kobj_map *bdev_map; | |
219 | ||
220 | /* | |
221 | * Register device numbers dev..(dev+range-1) | |
222 | * range must be nonzero | |
223 | * The hash chain is sorted on range, so that subranges can override. | |
224 | */ | |
225 | void blk_register_region(dev_t dev, unsigned long range, struct module *module, | |
226 | struct kobject *(*probe)(dev_t, int *, void *), | |
227 | int (*lock)(dev_t, void *), void *data) | |
228 | { | |
229 | kobj_map(bdev_map, dev, range, module, probe, lock, data); | |
230 | } | |
231 | ||
232 | EXPORT_SYMBOL(blk_register_region); | |
233 | ||
234 | void blk_unregister_region(dev_t dev, unsigned long range) | |
235 | { | |
236 | kobj_unmap(bdev_map, dev, range); | |
237 | } | |
238 | ||
239 | EXPORT_SYMBOL(blk_unregister_region); | |
240 | ||
241 | static struct kobject *exact_match(dev_t dev, int *part, void *data) | |
242 | { | |
243 | struct gendisk *p = data; | |
244 | return &p->kobj; | |
245 | } | |
246 | ||
247 | static int exact_lock(dev_t dev, void *data) | |
248 | { | |
249 | struct gendisk *p = data; | |
250 | ||
251 | if (!get_disk(p)) | |
252 | return -1; | |
253 | return 0; | |
254 | } | |
255 | ||
256 | /** | |
257 | * add_disk - add partitioning information to kernel list | |
258 | * @disk: per-device partitioning information | |
259 | * | |
260 | * This function registers the partitioning information in @disk | |
261 | * with the kernel. | |
262 | */ | |
263 | void add_disk(struct gendisk *disk) | |
264 | { | |
265 | disk->flags |= GENHD_FL_UP; | |
266 | blk_register_region(MKDEV(disk->major, disk->first_minor), | |
267 | disk->minors, NULL, exact_match, exact_lock, disk); | |
268 | register_disk(disk); | |
269 | blk_register_queue(disk); | |
270 | } | |
271 | ||
272 | EXPORT_SYMBOL(add_disk); | |
273 | EXPORT_SYMBOL(del_gendisk); /* in partitions/check.c */ | |
274 | ||
275 | void unlink_gendisk(struct gendisk *disk) | |
276 | { | |
277 | blk_unregister_queue(disk); | |
278 | blk_unregister_region(MKDEV(disk->major, disk->first_minor), | |
279 | disk->minors); | |
280 | } | |
281 | ||
282 | #define to_disk(obj) container_of(obj,struct gendisk,kobj) | |
283 | ||
284 | /** | |
285 | * get_gendisk - get partitioning information for a given device | |
286 | * @dev: device to get partitioning information for | |
287 | * | |
288 | * This function gets the structure containing partitioning | |
289 | * information for the given device @dev. | |
290 | */ | |
291 | struct gendisk *get_gendisk(dev_t dev, int *part) | |
292 | { | |
293 | struct kobject *kobj = kobj_lookup(bdev_map, dev, part); | |
294 | return kobj ? to_disk(kobj) : NULL; | |
295 | } | |
296 | ||
297 | #ifdef CONFIG_PROC_FS | |
298 | /* iterator */ | |
299 | static void *part_start(struct seq_file *part, loff_t *pos) | |
300 | { | |
301 | struct list_head *p; | |
302 | loff_t l = *pos; | |
303 | ||
304 | down(&block_subsys_sem); | |
305 | list_for_each(p, &block_subsys.kset.list) | |
306 | if (!l--) | |
307 | return list_entry(p, struct gendisk, kobj.entry); | |
308 | return NULL; | |
309 | } | |
310 | ||
311 | static void *part_next(struct seq_file *part, void *v, loff_t *pos) | |
312 | { | |
313 | struct list_head *p = ((struct gendisk *)v)->kobj.entry.next; | |
314 | ++*pos; | |
315 | return p==&block_subsys.kset.list ? NULL : | |
316 | list_entry(p, struct gendisk, kobj.entry); | |
317 | } | |
318 | ||
319 | static void part_stop(struct seq_file *part, void *v) | |
320 | { | |
321 | up(&block_subsys_sem); | |
322 | } | |
323 | ||
324 | static int show_partition(struct seq_file *part, void *v) | |
325 | { | |
326 | struct gendisk *sgp = v; | |
327 | int n; | |
328 | char buf[BDEVNAME_SIZE]; | |
329 | ||
330 | if (&sgp->kobj.entry == block_subsys.kset.list.next) | |
331 | seq_puts(part, "major minor #blocks name\n\n"); | |
332 | ||
333 | /* Don't show non-partitionable removeable devices or empty devices */ | |
334 | if (!get_capacity(sgp) || | |
335 | (sgp->minors == 1 && (sgp->flags & GENHD_FL_REMOVABLE))) | |
336 | return 0; | |
337 | if (sgp->flags & GENHD_FL_SUPPRESS_PARTITION_INFO) | |
338 | return 0; | |
339 | ||
340 | /* show the full disk and all non-0 size partitions of it */ | |
341 | seq_printf(part, "%4d %4d %10llu %s\n", | |
342 | sgp->major, sgp->first_minor, | |
343 | (unsigned long long)get_capacity(sgp) >> 1, | |
344 | disk_name(sgp, 0, buf)); | |
345 | for (n = 0; n < sgp->minors - 1; n++) { | |
346 | if (!sgp->part[n]) | |
347 | continue; | |
348 | if (sgp->part[n]->nr_sects == 0) | |
349 | continue; | |
350 | seq_printf(part, "%4d %4d %10llu %s\n", | |
351 | sgp->major, n + 1 + sgp->first_minor, | |
352 | (unsigned long long)sgp->part[n]->nr_sects >> 1 , | |
353 | disk_name(sgp, n + 1, buf)); | |
354 | } | |
355 | ||
356 | return 0; | |
357 | } | |
358 | ||
359 | struct seq_operations partitions_op = { | |
360 | .start =part_start, | |
361 | .next = part_next, | |
362 | .stop = part_stop, | |
363 | .show = show_partition | |
364 | }; | |
365 | #endif | |
366 | ||
367 | ||
368 | extern int blk_dev_init(void); | |
369 | ||
370 | static struct kobject *base_probe(dev_t dev, int *part, void *data) | |
371 | { | |
372 | if (request_module("block-major-%d-%d", MAJOR(dev), MINOR(dev)) > 0) | |
373 | /* Make old-style 2.4 aliases work */ | |
374 | request_module("block-major-%d", MAJOR(dev)); | |
375 | return NULL; | |
376 | } | |
377 | ||
378 | static int __init genhd_device_init(void) | |
379 | { | |
380 | bdev_map = kobj_map_init(base_probe, &block_subsys_sem); | |
381 | blk_dev_init(); | |
382 | subsystem_register(&block_subsys); | |
383 | return 0; | |
384 | } | |
385 | ||
386 | subsys_initcall(genhd_device_init); | |
387 | ||
388 | ||
389 | ||
390 | /* | |
391 | * kobject & sysfs bindings for block devices | |
392 | */ | |
393 | static ssize_t disk_attr_show(struct kobject *kobj, struct attribute *attr, | |
394 | char *page) | |
395 | { | |
396 | struct gendisk *disk = to_disk(kobj); | |
397 | struct disk_attribute *disk_attr = | |
398 | container_of(attr,struct disk_attribute,attr); | |
6c1852a0 | 399 | ssize_t ret = -EIO; |
1da177e4 LT |
400 | |
401 | if (disk_attr->show) | |
402 | ret = disk_attr->show(disk,page); | |
403 | return ret; | |
404 | } | |
405 | ||
a7fd6706 KS |
406 | static ssize_t disk_attr_store(struct kobject * kobj, struct attribute * attr, |
407 | const char *page, size_t count) | |
408 | { | |
409 | struct gendisk *disk = to_disk(kobj); | |
410 | struct disk_attribute *disk_attr = | |
411 | container_of(attr,struct disk_attribute,attr); | |
412 | ssize_t ret = 0; | |
413 | ||
414 | if (disk_attr->store) | |
415 | ret = disk_attr->store(disk, page, count); | |
416 | return ret; | |
417 | } | |
418 | ||
1da177e4 LT |
419 | static struct sysfs_ops disk_sysfs_ops = { |
420 | .show = &disk_attr_show, | |
a7fd6706 | 421 | .store = &disk_attr_store, |
1da177e4 LT |
422 | }; |
423 | ||
a7fd6706 KS |
424 | static ssize_t disk_uevent_store(struct gendisk * disk, |
425 | const char *buf, size_t count) | |
426 | { | |
312c004d | 427 | kobject_uevent(&disk->kobj, KOBJ_ADD); |
a7fd6706 KS |
428 | return count; |
429 | } | |
1da177e4 LT |
430 | static ssize_t disk_dev_read(struct gendisk * disk, char *page) |
431 | { | |
432 | dev_t base = MKDEV(disk->major, disk->first_minor); | |
433 | return print_dev_t(page, base); | |
434 | } | |
435 | static ssize_t disk_range_read(struct gendisk * disk, char *page) | |
436 | { | |
437 | return sprintf(page, "%d\n", disk->minors); | |
438 | } | |
439 | static ssize_t disk_removable_read(struct gendisk * disk, char *page) | |
440 | { | |
441 | return sprintf(page, "%d\n", | |
442 | (disk->flags & GENHD_FL_REMOVABLE ? 1 : 0)); | |
443 | ||
444 | } | |
445 | static ssize_t disk_size_read(struct gendisk * disk, char *page) | |
446 | { | |
447 | return sprintf(page, "%llu\n", (unsigned long long)get_capacity(disk)); | |
448 | } | |
449 | ||
450 | static ssize_t disk_stats_read(struct gendisk * disk, char *page) | |
451 | { | |
452 | preempt_disable(); | |
453 | disk_round_stats(disk); | |
454 | preempt_enable(); | |
455 | return sprintf(page, | |
456 | "%8u %8u %8llu %8u " | |
457 | "%8u %8u %8llu %8u " | |
458 | "%8u %8u %8u" | |
459 | "\n", | |
47a00410 JA |
460 | disk_stat_read(disk, ios[READ]), |
461 | disk_stat_read(disk, merges[READ]), | |
462 | (unsigned long long)disk_stat_read(disk, sectors[READ]), | |
463 | jiffies_to_msecs(disk_stat_read(disk, ticks[READ])), | |
464 | disk_stat_read(disk, ios[WRITE]), | |
465 | disk_stat_read(disk, merges[WRITE]), | |
466 | (unsigned long long)disk_stat_read(disk, sectors[WRITE]), | |
467 | jiffies_to_msecs(disk_stat_read(disk, ticks[WRITE])), | |
1da177e4 LT |
468 | disk->in_flight, |
469 | jiffies_to_msecs(disk_stat_read(disk, io_ticks)), | |
470 | jiffies_to_msecs(disk_stat_read(disk, time_in_queue))); | |
471 | } | |
a7fd6706 KS |
472 | static struct disk_attribute disk_attr_uevent = { |
473 | .attr = {.name = "uevent", .mode = S_IWUSR }, | |
474 | .store = disk_uevent_store | |
475 | }; | |
1da177e4 LT |
476 | static struct disk_attribute disk_attr_dev = { |
477 | .attr = {.name = "dev", .mode = S_IRUGO }, | |
478 | .show = disk_dev_read | |
479 | }; | |
480 | static struct disk_attribute disk_attr_range = { | |
481 | .attr = {.name = "range", .mode = S_IRUGO }, | |
482 | .show = disk_range_read | |
483 | }; | |
484 | static struct disk_attribute disk_attr_removable = { | |
485 | .attr = {.name = "removable", .mode = S_IRUGO }, | |
486 | .show = disk_removable_read | |
487 | }; | |
488 | static struct disk_attribute disk_attr_size = { | |
489 | .attr = {.name = "size", .mode = S_IRUGO }, | |
490 | .show = disk_size_read | |
491 | }; | |
492 | static struct disk_attribute disk_attr_stat = { | |
493 | .attr = {.name = "stat", .mode = S_IRUGO }, | |
494 | .show = disk_stats_read | |
495 | }; | |
496 | ||
497 | static struct attribute * default_attrs[] = { | |
a7fd6706 | 498 | &disk_attr_uevent.attr, |
1da177e4 LT |
499 | &disk_attr_dev.attr, |
500 | &disk_attr_range.attr, | |
501 | &disk_attr_removable.attr, | |
502 | &disk_attr_size.attr, | |
503 | &disk_attr_stat.attr, | |
504 | NULL, | |
505 | }; | |
506 | ||
507 | static void disk_release(struct kobject * kobj) | |
508 | { | |
509 | struct gendisk *disk = to_disk(kobj); | |
510 | kfree(disk->random); | |
511 | kfree(disk->part); | |
512 | free_disk_stats(disk); | |
513 | kfree(disk); | |
514 | } | |
515 | ||
516 | static struct kobj_type ktype_block = { | |
517 | .release = disk_release, | |
518 | .sysfs_ops = &disk_sysfs_ops, | |
519 | .default_attrs = default_attrs, | |
520 | }; | |
521 | ||
522 | extern struct kobj_type ktype_part; | |
523 | ||
312c004d | 524 | static int block_uevent_filter(struct kset *kset, struct kobject *kobj) |
1da177e4 LT |
525 | { |
526 | struct kobj_type *ktype = get_ktype(kobj); | |
527 | ||
528 | return ((ktype == &ktype_block) || (ktype == &ktype_part)); | |
529 | } | |
530 | ||
312c004d | 531 | static int block_uevent(struct kset *kset, struct kobject *kobj, char **envp, |
1da177e4 LT |
532 | int num_envp, char *buffer, int buffer_size) |
533 | { | |
534 | struct kobj_type *ktype = get_ktype(kobj); | |
535 | struct device *physdev; | |
536 | struct gendisk *disk; | |
537 | struct hd_struct *part; | |
538 | int length = 0; | |
539 | int i = 0; | |
540 | ||
541 | if (ktype == &ktype_block) { | |
542 | disk = container_of(kobj, struct gendisk, kobj); | |
312c004d KS |
543 | add_uevent_var(envp, num_envp, &i, buffer, buffer_size, |
544 | &length, "MINOR=%u", disk->first_minor); | |
1da177e4 LT |
545 | } else if (ktype == &ktype_part) { |
546 | disk = container_of(kobj->parent, struct gendisk, kobj); | |
547 | part = container_of(kobj, struct hd_struct, kobj); | |
312c004d KS |
548 | add_uevent_var(envp, num_envp, &i, buffer, buffer_size, |
549 | &length, "MINOR=%u", | |
550 | disk->first_minor + part->partno); | |
1da177e4 LT |
551 | } else |
552 | return 0; | |
553 | ||
312c004d KS |
554 | add_uevent_var(envp, num_envp, &i, buffer, buffer_size, &length, |
555 | "MAJOR=%u", disk->major); | |
1da177e4 LT |
556 | |
557 | /* add physical device, backing this device */ | |
558 | physdev = disk->driverfs_dev; | |
559 | if (physdev) { | |
560 | char *path = kobject_get_path(&physdev->kobj, GFP_KERNEL); | |
561 | ||
312c004d KS |
562 | add_uevent_var(envp, num_envp, &i, buffer, buffer_size, |
563 | &length, "PHYSDEVPATH=%s", path); | |
1da177e4 LT |
564 | kfree(path); |
565 | ||
566 | if (physdev->bus) | |
312c004d KS |
567 | add_uevent_var(envp, num_envp, &i, |
568 | buffer, buffer_size, &length, | |
569 | "PHYSDEVBUS=%s", | |
570 | physdev->bus->name); | |
1da177e4 LT |
571 | |
572 | if (physdev->driver) | |
312c004d KS |
573 | add_uevent_var(envp, num_envp, &i, |
574 | buffer, buffer_size, &length, | |
575 | "PHYSDEVDRIVER=%s", | |
576 | physdev->driver->name); | |
1da177e4 LT |
577 | } |
578 | ||
579 | /* terminate, set to next free slot, shrink available space */ | |
580 | envp[i] = NULL; | |
581 | envp = &envp[i]; | |
582 | num_envp -= i; | |
583 | buffer = &buffer[length]; | |
584 | buffer_size -= length; | |
585 | ||
586 | return 0; | |
587 | } | |
588 | ||
312c004d KS |
589 | static struct kset_uevent_ops block_uevent_ops = { |
590 | .filter = block_uevent_filter, | |
591 | .uevent = block_uevent, | |
1da177e4 LT |
592 | }; |
593 | ||
594 | /* declare block_subsys. */ | |
312c004d | 595 | static decl_subsys(block, &ktype_block, &block_uevent_ops); |
1da177e4 LT |
596 | |
597 | ||
598 | /* | |
599 | * aggregate disk stat collector. Uses the same stats that the sysfs | |
600 | * entries do, above, but makes them available through one seq_file. | |
601 | * Watching a few disks may be efficient through sysfs, but watching | |
602 | * all of them will be more efficient through this interface. | |
603 | * | |
604 | * The output looks suspiciously like /proc/partitions with a bunch of | |
605 | * extra fields. | |
606 | */ | |
607 | ||
608 | /* iterator */ | |
609 | static void *diskstats_start(struct seq_file *part, loff_t *pos) | |
610 | { | |
611 | loff_t k = *pos; | |
612 | struct list_head *p; | |
613 | ||
614 | down(&block_subsys_sem); | |
615 | list_for_each(p, &block_subsys.kset.list) | |
616 | if (!k--) | |
617 | return list_entry(p, struct gendisk, kobj.entry); | |
618 | return NULL; | |
619 | } | |
620 | ||
621 | static void *diskstats_next(struct seq_file *part, void *v, loff_t *pos) | |
622 | { | |
623 | struct list_head *p = ((struct gendisk *)v)->kobj.entry.next; | |
624 | ++*pos; | |
625 | return p==&block_subsys.kset.list ? NULL : | |
626 | list_entry(p, struct gendisk, kobj.entry); | |
627 | } | |
628 | ||
629 | static void diskstats_stop(struct seq_file *part, void *v) | |
630 | { | |
631 | up(&block_subsys_sem); | |
632 | } | |
633 | ||
634 | static int diskstats_show(struct seq_file *s, void *v) | |
635 | { | |
636 | struct gendisk *gp = v; | |
637 | char buf[BDEVNAME_SIZE]; | |
638 | int n = 0; | |
639 | ||
640 | /* | |
641 | if (&sgp->kobj.entry == block_subsys.kset.list.next) | |
642 | seq_puts(s, "major minor name" | |
643 | " rio rmerge rsect ruse wio wmerge " | |
644 | "wsect wuse running use aveq" | |
645 | "\n\n"); | |
646 | */ | |
647 | ||
648 | preempt_disable(); | |
649 | disk_round_stats(gp); | |
650 | preempt_enable(); | |
651 | seq_printf(s, "%4d %4d %s %u %u %llu %u %u %u %llu %u %u %u %u\n", | |
652 | gp->major, n + gp->first_minor, disk_name(gp, n, buf), | |
a362357b JA |
653 | disk_stat_read(gp, ios[0]), disk_stat_read(gp, merges[0]), |
654 | (unsigned long long)disk_stat_read(gp, sectors[0]), | |
655 | jiffies_to_msecs(disk_stat_read(gp, ticks[0])), | |
656 | disk_stat_read(gp, ios[1]), disk_stat_read(gp, merges[1]), | |
657 | (unsigned long long)disk_stat_read(gp, sectors[1]), | |
658 | jiffies_to_msecs(disk_stat_read(gp, ticks[1])), | |
1da177e4 LT |
659 | gp->in_flight, |
660 | jiffies_to_msecs(disk_stat_read(gp, io_ticks)), | |
661 | jiffies_to_msecs(disk_stat_read(gp, time_in_queue))); | |
662 | ||
663 | /* now show all non-0 size partitions of it */ | |
664 | for (n = 0; n < gp->minors - 1; n++) { | |
665 | struct hd_struct *hd = gp->part[n]; | |
666 | ||
667 | if (hd && hd->nr_sects) | |
668 | seq_printf(s, "%4d %4d %s %u %u %u %u\n", | |
669 | gp->major, n + gp->first_minor + 1, | |
670 | disk_name(gp, n + 1, buf), | |
a362357b JA |
671 | hd->ios[0], hd->sectors[0], |
672 | hd->ios[1], hd->sectors[1]); | |
1da177e4 LT |
673 | } |
674 | ||
675 | return 0; | |
676 | } | |
677 | ||
678 | struct seq_operations diskstats_op = { | |
679 | .start = diskstats_start, | |
680 | .next = diskstats_next, | |
681 | .stop = diskstats_stop, | |
682 | .show = diskstats_show | |
683 | }; | |
684 | ||
1da177e4 LT |
685 | struct gendisk *alloc_disk(int minors) |
686 | { | |
1946089a CL |
687 | return alloc_disk_node(minors, -1); |
688 | } | |
689 | ||
690 | struct gendisk *alloc_disk_node(int minors, int node_id) | |
691 | { | |
692 | struct gendisk *disk; | |
693 | ||
694 | disk = kmalloc_node(sizeof(struct gendisk), GFP_KERNEL, node_id); | |
1da177e4 LT |
695 | if (disk) { |
696 | memset(disk, 0, sizeof(struct gendisk)); | |
697 | if (!init_disk_stats(disk)) { | |
698 | kfree(disk); | |
699 | return NULL; | |
700 | } | |
701 | if (minors > 1) { | |
702 | int size = (minors - 1) * sizeof(struct hd_struct *); | |
1946089a | 703 | disk->part = kmalloc_node(size, GFP_KERNEL, node_id); |
1da177e4 LT |
704 | if (!disk->part) { |
705 | kfree(disk); | |
706 | return NULL; | |
707 | } | |
708 | memset(disk->part, 0, size); | |
709 | } | |
710 | disk->minors = minors; | |
711 | kobj_set_kset_s(disk,block_subsys); | |
712 | kobject_init(&disk->kobj); | |
713 | rand_initialize_disk(disk); | |
714 | } | |
715 | return disk; | |
716 | } | |
717 | ||
718 | EXPORT_SYMBOL(alloc_disk); | |
1946089a | 719 | EXPORT_SYMBOL(alloc_disk_node); |
1da177e4 LT |
720 | |
721 | struct kobject *get_disk(struct gendisk *disk) | |
722 | { | |
723 | struct module *owner; | |
724 | struct kobject *kobj; | |
725 | ||
726 | if (!disk->fops) | |
727 | return NULL; | |
728 | owner = disk->fops->owner; | |
729 | if (owner && !try_module_get(owner)) | |
730 | return NULL; | |
731 | kobj = kobject_get(&disk->kobj); | |
732 | if (kobj == NULL) { | |
733 | module_put(owner); | |
734 | return NULL; | |
735 | } | |
736 | return kobj; | |
737 | ||
738 | } | |
739 | ||
740 | EXPORT_SYMBOL(get_disk); | |
741 | ||
742 | void put_disk(struct gendisk *disk) | |
743 | { | |
744 | if (disk) | |
745 | kobject_put(&disk->kobj); | |
746 | } | |
747 | ||
748 | EXPORT_SYMBOL(put_disk); | |
749 | ||
750 | void set_device_ro(struct block_device *bdev, int flag) | |
751 | { | |
752 | if (bdev->bd_contains != bdev) | |
753 | bdev->bd_part->policy = flag; | |
754 | else | |
755 | bdev->bd_disk->policy = flag; | |
756 | } | |
757 | ||
758 | EXPORT_SYMBOL(set_device_ro); | |
759 | ||
760 | void set_disk_ro(struct gendisk *disk, int flag) | |
761 | { | |
762 | int i; | |
763 | disk->policy = flag; | |
764 | for (i = 0; i < disk->minors - 1; i++) | |
765 | if (disk->part[i]) disk->part[i]->policy = flag; | |
766 | } | |
767 | ||
768 | EXPORT_SYMBOL(set_disk_ro); | |
769 | ||
770 | int bdev_read_only(struct block_device *bdev) | |
771 | { | |
772 | if (!bdev) | |
773 | return 0; | |
774 | else if (bdev->bd_contains != bdev) | |
775 | return bdev->bd_part->policy; | |
776 | else | |
777 | return bdev->bd_disk->policy; | |
778 | } | |
779 | ||
780 | EXPORT_SYMBOL(bdev_read_only); | |
781 | ||
782 | int invalidate_partition(struct gendisk *disk, int index) | |
783 | { | |
784 | int res = 0; | |
785 | struct block_device *bdev = bdget_disk(disk, index); | |
786 | if (bdev) { | |
2ef41634 CH |
787 | fsync_bdev(bdev); |
788 | res = __invalidate_device(bdev); | |
1da177e4 LT |
789 | bdput(bdev); |
790 | } | |
791 | return res; | |
792 | } | |
793 | ||
794 | EXPORT_SYMBOL(invalidate_partition); |