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> |
58383af6 | 18 | #include <linux/mutex.h> |
1da177e4 LT |
19 | |
20 | #define MAX_PROBE_HASH 255 /* random */ | |
21 | ||
22 | static struct subsystem block_subsys; | |
23 | ||
58383af6 | 24 | static DEFINE_MUTEX(block_subsys_lock); |
1da177e4 LT |
25 | |
26 | /* | |
27 | * Can be deleted altogether. Later. | |
28 | * | |
29 | */ | |
30 | static struct blk_major_name { | |
31 | struct blk_major_name *next; | |
32 | int major; | |
33 | char name[16]; | |
34 | } *major_names[MAX_PROBE_HASH]; | |
35 | ||
36 | /* index in the above - for now: assume no multimajor ranges */ | |
37 | static inline int major_to_index(int major) | |
38 | { | |
39 | return major % MAX_PROBE_HASH; | |
40 | } | |
41 | ||
7170be5f NH |
42 | struct blkdev_info { |
43 | int index; | |
44 | struct blk_major_name *bd; | |
45 | }; | |
46 | ||
47 | /* | |
48 | * iterate over a list of blkdev_info structures. allows | |
49 | * the major_names array to be iterated over from outside this file | |
58383af6 | 50 | * must be called with the block_subsys_lock held |
7170be5f NH |
51 | */ |
52 | void *get_next_blkdev(void *dev) | |
53 | { | |
54 | struct blkdev_info *info; | |
55 | ||
56 | if (dev == NULL) { | |
57 | info = kmalloc(sizeof(*info), GFP_KERNEL); | |
58 | if (!info) | |
59 | goto out; | |
60 | info->index=0; | |
61 | info->bd = major_names[info->index]; | |
62 | if (info->bd) | |
63 | goto out; | |
64 | } else { | |
65 | info = dev; | |
66 | } | |
67 | ||
68 | while (info->index < ARRAY_SIZE(major_names)) { | |
69 | if (info->bd) | |
70 | info->bd = info->bd->next; | |
71 | if (info->bd) | |
72 | goto out; | |
73 | /* | |
74 | * No devices on this chain, move to the next | |
75 | */ | |
76 | info->index++; | |
77 | info->bd = (info->index < ARRAY_SIZE(major_names)) ? | |
78 | major_names[info->index] : NULL; | |
79 | if (info->bd) | |
80 | goto out; | |
81 | } | |
82 | ||
83 | out: | |
84 | return info; | |
85 | } | |
86 | ||
87 | void *acquire_blkdev_list(void) | |
88 | { | |
58383af6 | 89 | mutex_lock(&block_subsys_lock); |
7170be5f NH |
90 | return get_next_blkdev(NULL); |
91 | } | |
92 | ||
93 | void release_blkdev_list(void *dev) | |
94 | { | |
58383af6 | 95 | mutex_unlock(&block_subsys_lock); |
7170be5f NH |
96 | kfree(dev); |
97 | } | |
98 | ||
99 | ||
100 | /* | |
101 | * Count the number of records in the blkdev_list. | |
58383af6 | 102 | * must be called with the block_subsys_lock held |
7170be5f NH |
103 | */ |
104 | int count_blkdev_list(void) | |
1da177e4 LT |
105 | { |
106 | struct blk_major_name *n; | |
7170be5f | 107 | int i, count; |
1da177e4 | 108 | |
7170be5f | 109 | count = 0; |
1da177e4 | 110 | |
1da177e4 | 111 | for (i = 0; i < ARRAY_SIZE(major_names); i++) { |
7170be5f NH |
112 | for (n = major_names[i]; n; n = n->next) |
113 | count++; | |
1da177e4 | 114 | } |
1da177e4 | 115 | |
7170be5f NH |
116 | return count; |
117 | } | |
118 | ||
119 | /* | |
120 | * extract the major and name values from a blkdev_info struct | |
121 | * passed in as a void to *dev. Must be called with | |
58383af6 | 122 | * block_subsys_lock held |
7170be5f NH |
123 | */ |
124 | int get_blkdev_info(void *dev, int *major, char **name) | |
125 | { | |
126 | struct blkdev_info *info = dev; | |
127 | ||
128 | if (info->bd == NULL) | |
129 | return 1; | |
130 | ||
131 | *major = info->bd->major; | |
132 | *name = info->bd->name; | |
133 | return 0; | |
1da177e4 | 134 | } |
7170be5f | 135 | |
1da177e4 LT |
136 | |
137 | int register_blkdev(unsigned int major, const char *name) | |
138 | { | |
139 | struct blk_major_name **n, *p; | |
140 | int index, ret = 0; | |
141 | ||
58383af6 | 142 | mutex_lock(&block_subsys_lock); |
1da177e4 LT |
143 | |
144 | /* temporary */ | |
145 | if (major == 0) { | |
146 | for (index = ARRAY_SIZE(major_names)-1; index > 0; index--) { | |
147 | if (major_names[index] == NULL) | |
148 | break; | |
149 | } | |
150 | ||
151 | if (index == 0) { | |
152 | printk("register_blkdev: failed to get major for %s\n", | |
153 | name); | |
154 | ret = -EBUSY; | |
155 | goto out; | |
156 | } | |
157 | major = index; | |
158 | ret = major; | |
159 | } | |
160 | ||
161 | p = kmalloc(sizeof(struct blk_major_name), GFP_KERNEL); | |
162 | if (p == NULL) { | |
163 | ret = -ENOMEM; | |
164 | goto out; | |
165 | } | |
166 | ||
167 | p->major = major; | |
168 | strlcpy(p->name, name, sizeof(p->name)); | |
169 | p->next = NULL; | |
170 | index = major_to_index(major); | |
171 | ||
172 | for (n = &major_names[index]; *n; n = &(*n)->next) { | |
173 | if ((*n)->major == major) | |
174 | break; | |
175 | } | |
176 | if (!*n) | |
177 | *n = p; | |
178 | else | |
179 | ret = -EBUSY; | |
180 | ||
181 | if (ret < 0) { | |
182 | printk("register_blkdev: cannot get major %d for %s\n", | |
183 | major, name); | |
184 | kfree(p); | |
185 | } | |
186 | out: | |
58383af6 | 187 | mutex_unlock(&block_subsys_lock); |
1da177e4 LT |
188 | return ret; |
189 | } | |
190 | ||
191 | EXPORT_SYMBOL(register_blkdev); | |
192 | ||
193 | /* todo: make void - error printk here */ | |
194 | int unregister_blkdev(unsigned int major, const char *name) | |
195 | { | |
196 | struct blk_major_name **n; | |
197 | struct blk_major_name *p = NULL; | |
198 | int index = major_to_index(major); | |
199 | int ret = 0; | |
200 | ||
58383af6 | 201 | mutex_lock(&block_subsys_lock); |
1da177e4 LT |
202 | for (n = &major_names[index]; *n; n = &(*n)->next) |
203 | if ((*n)->major == major) | |
204 | break; | |
205 | if (!*n || strcmp((*n)->name, name)) | |
206 | ret = -EINVAL; | |
207 | else { | |
208 | p = *n; | |
209 | *n = p->next; | |
210 | } | |
58383af6 | 211 | mutex_unlock(&block_subsys_lock); |
1da177e4 LT |
212 | kfree(p); |
213 | ||
214 | return ret; | |
215 | } | |
216 | ||
217 | EXPORT_SYMBOL(unregister_blkdev); | |
218 | ||
219 | static struct kobj_map *bdev_map; | |
220 | ||
221 | /* | |
222 | * Register device numbers dev..(dev+range-1) | |
223 | * range must be nonzero | |
224 | * The hash chain is sorted on range, so that subranges can override. | |
225 | */ | |
226 | void blk_register_region(dev_t dev, unsigned long range, struct module *module, | |
227 | struct kobject *(*probe)(dev_t, int *, void *), | |
228 | int (*lock)(dev_t, void *), void *data) | |
229 | { | |
230 | kobj_map(bdev_map, dev, range, module, probe, lock, data); | |
231 | } | |
232 | ||
233 | EXPORT_SYMBOL(blk_register_region); | |
234 | ||
235 | void blk_unregister_region(dev_t dev, unsigned long range) | |
236 | { | |
237 | kobj_unmap(bdev_map, dev, range); | |
238 | } | |
239 | ||
240 | EXPORT_SYMBOL(blk_unregister_region); | |
241 | ||
242 | static struct kobject *exact_match(dev_t dev, int *part, void *data) | |
243 | { | |
244 | struct gendisk *p = data; | |
245 | return &p->kobj; | |
246 | } | |
247 | ||
248 | static int exact_lock(dev_t dev, void *data) | |
249 | { | |
250 | struct gendisk *p = data; | |
251 | ||
252 | if (!get_disk(p)) | |
253 | return -1; | |
254 | return 0; | |
255 | } | |
256 | ||
257 | /** | |
258 | * add_disk - add partitioning information to kernel list | |
259 | * @disk: per-device partitioning information | |
260 | * | |
261 | * This function registers the partitioning information in @disk | |
262 | * with the kernel. | |
263 | */ | |
264 | void add_disk(struct gendisk *disk) | |
265 | { | |
266 | disk->flags |= GENHD_FL_UP; | |
267 | blk_register_region(MKDEV(disk->major, disk->first_minor), | |
268 | disk->minors, NULL, exact_match, exact_lock, disk); | |
269 | register_disk(disk); | |
270 | blk_register_queue(disk); | |
271 | } | |
272 | ||
273 | EXPORT_SYMBOL(add_disk); | |
274 | EXPORT_SYMBOL(del_gendisk); /* in partitions/check.c */ | |
275 | ||
276 | void unlink_gendisk(struct gendisk *disk) | |
277 | { | |
278 | blk_unregister_queue(disk); | |
279 | blk_unregister_region(MKDEV(disk->major, disk->first_minor), | |
280 | disk->minors); | |
281 | } | |
282 | ||
283 | #define to_disk(obj) container_of(obj,struct gendisk,kobj) | |
284 | ||
285 | /** | |
286 | * get_gendisk - get partitioning information for a given device | |
287 | * @dev: device to get partitioning information for | |
288 | * | |
289 | * This function gets the structure containing partitioning | |
290 | * information for the given device @dev. | |
291 | */ | |
292 | struct gendisk *get_gendisk(dev_t dev, int *part) | |
293 | { | |
294 | struct kobject *kobj = kobj_lookup(bdev_map, dev, part); | |
295 | return kobj ? to_disk(kobj) : NULL; | |
296 | } | |
297 | ||
298 | #ifdef CONFIG_PROC_FS | |
299 | /* iterator */ | |
300 | static void *part_start(struct seq_file *part, loff_t *pos) | |
301 | { | |
302 | struct list_head *p; | |
303 | loff_t l = *pos; | |
304 | ||
58383af6 | 305 | mutex_lock(&block_subsys_lock); |
1da177e4 LT |
306 | list_for_each(p, &block_subsys.kset.list) |
307 | if (!l--) | |
308 | return list_entry(p, struct gendisk, kobj.entry); | |
309 | return NULL; | |
310 | } | |
311 | ||
312 | static void *part_next(struct seq_file *part, void *v, loff_t *pos) | |
313 | { | |
314 | struct list_head *p = ((struct gendisk *)v)->kobj.entry.next; | |
315 | ++*pos; | |
316 | return p==&block_subsys.kset.list ? NULL : | |
317 | list_entry(p, struct gendisk, kobj.entry); | |
318 | } | |
319 | ||
320 | static void part_stop(struct seq_file *part, void *v) | |
321 | { | |
58383af6 | 322 | mutex_unlock(&block_subsys_lock); |
1da177e4 LT |
323 | } |
324 | ||
325 | static int show_partition(struct seq_file *part, void *v) | |
326 | { | |
327 | struct gendisk *sgp = v; | |
328 | int n; | |
329 | char buf[BDEVNAME_SIZE]; | |
330 | ||
331 | if (&sgp->kobj.entry == block_subsys.kset.list.next) | |
332 | seq_puts(part, "major minor #blocks name\n\n"); | |
333 | ||
334 | /* Don't show non-partitionable removeable devices or empty devices */ | |
335 | if (!get_capacity(sgp) || | |
336 | (sgp->minors == 1 && (sgp->flags & GENHD_FL_REMOVABLE))) | |
337 | return 0; | |
338 | if (sgp->flags & GENHD_FL_SUPPRESS_PARTITION_INFO) | |
339 | return 0; | |
340 | ||
341 | /* show the full disk and all non-0 size partitions of it */ | |
342 | seq_printf(part, "%4d %4d %10llu %s\n", | |
343 | sgp->major, sgp->first_minor, | |
344 | (unsigned long long)get_capacity(sgp) >> 1, | |
345 | disk_name(sgp, 0, buf)); | |
346 | for (n = 0; n < sgp->minors - 1; n++) { | |
347 | if (!sgp->part[n]) | |
348 | continue; | |
349 | if (sgp->part[n]->nr_sects == 0) | |
350 | continue; | |
351 | seq_printf(part, "%4d %4d %10llu %s\n", | |
352 | sgp->major, n + 1 + sgp->first_minor, | |
353 | (unsigned long long)sgp->part[n]->nr_sects >> 1 , | |
354 | disk_name(sgp, n + 1, buf)); | |
355 | } | |
356 | ||
357 | return 0; | |
358 | } | |
359 | ||
360 | struct seq_operations partitions_op = { | |
361 | .start =part_start, | |
362 | .next = part_next, | |
363 | .stop = part_stop, | |
364 | .show = show_partition | |
365 | }; | |
366 | #endif | |
367 | ||
368 | ||
369 | extern int blk_dev_init(void); | |
370 | ||
371 | static struct kobject *base_probe(dev_t dev, int *part, void *data) | |
372 | { | |
373 | if (request_module("block-major-%d-%d", MAJOR(dev), MINOR(dev)) > 0) | |
374 | /* Make old-style 2.4 aliases work */ | |
375 | request_module("block-major-%d", MAJOR(dev)); | |
376 | return NULL; | |
377 | } | |
378 | ||
379 | static int __init genhd_device_init(void) | |
380 | { | |
58383af6 | 381 | bdev_map = kobj_map_init(base_probe, &block_subsys_lock); |
1da177e4 LT |
382 | blk_dev_init(); |
383 | subsystem_register(&block_subsys); | |
384 | return 0; | |
385 | } | |
386 | ||
387 | subsys_initcall(genhd_device_init); | |
388 | ||
389 | ||
390 | ||
391 | /* | |
392 | * kobject & sysfs bindings for block devices | |
393 | */ | |
394 | static ssize_t disk_attr_show(struct kobject *kobj, struct attribute *attr, | |
395 | char *page) | |
396 | { | |
397 | struct gendisk *disk = to_disk(kobj); | |
398 | struct disk_attribute *disk_attr = | |
399 | container_of(attr,struct disk_attribute,attr); | |
6c1852a0 | 400 | ssize_t ret = -EIO; |
1da177e4 LT |
401 | |
402 | if (disk_attr->show) | |
403 | ret = disk_attr->show(disk,page); | |
404 | return ret; | |
405 | } | |
406 | ||
a7fd6706 KS |
407 | static ssize_t disk_attr_store(struct kobject * kobj, struct attribute * attr, |
408 | const char *page, size_t count) | |
409 | { | |
410 | struct gendisk *disk = to_disk(kobj); | |
411 | struct disk_attribute *disk_attr = | |
412 | container_of(attr,struct disk_attribute,attr); | |
413 | ssize_t ret = 0; | |
414 | ||
415 | if (disk_attr->store) | |
416 | ret = disk_attr->store(disk, page, count); | |
417 | return ret; | |
418 | } | |
419 | ||
1da177e4 LT |
420 | static struct sysfs_ops disk_sysfs_ops = { |
421 | .show = &disk_attr_show, | |
a7fd6706 | 422 | .store = &disk_attr_store, |
1da177e4 LT |
423 | }; |
424 | ||
a7fd6706 KS |
425 | static ssize_t disk_uevent_store(struct gendisk * disk, |
426 | const char *buf, size_t count) | |
427 | { | |
312c004d | 428 | kobject_uevent(&disk->kobj, KOBJ_ADD); |
a7fd6706 KS |
429 | return count; |
430 | } | |
1da177e4 LT |
431 | static ssize_t disk_dev_read(struct gendisk * disk, char *page) |
432 | { | |
433 | dev_t base = MKDEV(disk->major, disk->first_minor); | |
434 | return print_dev_t(page, base); | |
435 | } | |
436 | static ssize_t disk_range_read(struct gendisk * disk, char *page) | |
437 | { | |
438 | return sprintf(page, "%d\n", disk->minors); | |
439 | } | |
440 | static ssize_t disk_removable_read(struct gendisk * disk, char *page) | |
441 | { | |
442 | return sprintf(page, "%d\n", | |
443 | (disk->flags & GENHD_FL_REMOVABLE ? 1 : 0)); | |
444 | ||
445 | } | |
446 | static ssize_t disk_size_read(struct gendisk * disk, char *page) | |
447 | { | |
448 | return sprintf(page, "%llu\n", (unsigned long long)get_capacity(disk)); | |
449 | } | |
450 | ||
451 | static ssize_t disk_stats_read(struct gendisk * disk, char *page) | |
452 | { | |
453 | preempt_disable(); | |
454 | disk_round_stats(disk); | |
455 | preempt_enable(); | |
456 | return sprintf(page, | |
457 | "%8u %8u %8llu %8u " | |
458 | "%8u %8u %8llu %8u " | |
459 | "%8u %8u %8u" | |
460 | "\n", | |
47a00410 JA |
461 | disk_stat_read(disk, ios[READ]), |
462 | disk_stat_read(disk, merges[READ]), | |
463 | (unsigned long long)disk_stat_read(disk, sectors[READ]), | |
464 | jiffies_to_msecs(disk_stat_read(disk, ticks[READ])), | |
465 | disk_stat_read(disk, ios[WRITE]), | |
466 | disk_stat_read(disk, merges[WRITE]), | |
467 | (unsigned long long)disk_stat_read(disk, sectors[WRITE]), | |
468 | jiffies_to_msecs(disk_stat_read(disk, ticks[WRITE])), | |
1da177e4 LT |
469 | disk->in_flight, |
470 | jiffies_to_msecs(disk_stat_read(disk, io_ticks)), | |
471 | jiffies_to_msecs(disk_stat_read(disk, time_in_queue))); | |
472 | } | |
a7fd6706 KS |
473 | static struct disk_attribute disk_attr_uevent = { |
474 | .attr = {.name = "uevent", .mode = S_IWUSR }, | |
475 | .store = disk_uevent_store | |
476 | }; | |
1da177e4 LT |
477 | static struct disk_attribute disk_attr_dev = { |
478 | .attr = {.name = "dev", .mode = S_IRUGO }, | |
479 | .show = disk_dev_read | |
480 | }; | |
481 | static struct disk_attribute disk_attr_range = { | |
482 | .attr = {.name = "range", .mode = S_IRUGO }, | |
483 | .show = disk_range_read | |
484 | }; | |
485 | static struct disk_attribute disk_attr_removable = { | |
486 | .attr = {.name = "removable", .mode = S_IRUGO }, | |
487 | .show = disk_removable_read | |
488 | }; | |
489 | static struct disk_attribute disk_attr_size = { | |
490 | .attr = {.name = "size", .mode = S_IRUGO }, | |
491 | .show = disk_size_read | |
492 | }; | |
493 | static struct disk_attribute disk_attr_stat = { | |
494 | .attr = {.name = "stat", .mode = S_IRUGO }, | |
495 | .show = disk_stats_read | |
496 | }; | |
497 | ||
498 | static struct attribute * default_attrs[] = { | |
a7fd6706 | 499 | &disk_attr_uevent.attr, |
1da177e4 LT |
500 | &disk_attr_dev.attr, |
501 | &disk_attr_range.attr, | |
502 | &disk_attr_removable.attr, | |
503 | &disk_attr_size.attr, | |
504 | &disk_attr_stat.attr, | |
505 | NULL, | |
506 | }; | |
507 | ||
508 | static void disk_release(struct kobject * kobj) | |
509 | { | |
510 | struct gendisk *disk = to_disk(kobj); | |
511 | kfree(disk->random); | |
512 | kfree(disk->part); | |
513 | free_disk_stats(disk); | |
514 | kfree(disk); | |
515 | } | |
516 | ||
517 | static struct kobj_type ktype_block = { | |
518 | .release = disk_release, | |
519 | .sysfs_ops = &disk_sysfs_ops, | |
520 | .default_attrs = default_attrs, | |
521 | }; | |
522 | ||
523 | extern struct kobj_type ktype_part; | |
524 | ||
312c004d | 525 | static int block_uevent_filter(struct kset *kset, struct kobject *kobj) |
1da177e4 LT |
526 | { |
527 | struct kobj_type *ktype = get_ktype(kobj); | |
528 | ||
529 | return ((ktype == &ktype_block) || (ktype == &ktype_part)); | |
530 | } | |
531 | ||
312c004d | 532 | static int block_uevent(struct kset *kset, struct kobject *kobj, char **envp, |
1da177e4 LT |
533 | int num_envp, char *buffer, int buffer_size) |
534 | { | |
535 | struct kobj_type *ktype = get_ktype(kobj); | |
536 | struct device *physdev; | |
537 | struct gendisk *disk; | |
538 | struct hd_struct *part; | |
539 | int length = 0; | |
540 | int i = 0; | |
541 | ||
542 | if (ktype == &ktype_block) { | |
543 | disk = container_of(kobj, struct gendisk, kobj); | |
312c004d KS |
544 | add_uevent_var(envp, num_envp, &i, buffer, buffer_size, |
545 | &length, "MINOR=%u", disk->first_minor); | |
1da177e4 LT |
546 | } else if (ktype == &ktype_part) { |
547 | disk = container_of(kobj->parent, struct gendisk, kobj); | |
548 | part = container_of(kobj, struct hd_struct, kobj); | |
312c004d KS |
549 | add_uevent_var(envp, num_envp, &i, buffer, buffer_size, |
550 | &length, "MINOR=%u", | |
551 | disk->first_minor + part->partno); | |
1da177e4 LT |
552 | } else |
553 | return 0; | |
554 | ||
312c004d KS |
555 | add_uevent_var(envp, num_envp, &i, buffer, buffer_size, &length, |
556 | "MAJOR=%u", disk->major); | |
1da177e4 LT |
557 | |
558 | /* add physical device, backing this device */ | |
559 | physdev = disk->driverfs_dev; | |
560 | if (physdev) { | |
561 | char *path = kobject_get_path(&physdev->kobj, GFP_KERNEL); | |
562 | ||
312c004d KS |
563 | add_uevent_var(envp, num_envp, &i, buffer, buffer_size, |
564 | &length, "PHYSDEVPATH=%s", path); | |
1da177e4 LT |
565 | kfree(path); |
566 | ||
567 | if (physdev->bus) | |
312c004d KS |
568 | add_uevent_var(envp, num_envp, &i, |
569 | buffer, buffer_size, &length, | |
570 | "PHYSDEVBUS=%s", | |
571 | physdev->bus->name); | |
1da177e4 LT |
572 | |
573 | if (physdev->driver) | |
312c004d KS |
574 | add_uevent_var(envp, num_envp, &i, |
575 | buffer, buffer_size, &length, | |
576 | "PHYSDEVDRIVER=%s", | |
577 | physdev->driver->name); | |
1da177e4 LT |
578 | } |
579 | ||
580 | /* terminate, set to next free slot, shrink available space */ | |
581 | envp[i] = NULL; | |
582 | envp = &envp[i]; | |
583 | num_envp -= i; | |
584 | buffer = &buffer[length]; | |
585 | buffer_size -= length; | |
586 | ||
587 | return 0; | |
588 | } | |
589 | ||
312c004d KS |
590 | static struct kset_uevent_ops block_uevent_ops = { |
591 | .filter = block_uevent_filter, | |
592 | .uevent = block_uevent, | |
1da177e4 LT |
593 | }; |
594 | ||
595 | /* declare block_subsys. */ | |
312c004d | 596 | static decl_subsys(block, &ktype_block, &block_uevent_ops); |
1da177e4 LT |
597 | |
598 | ||
599 | /* | |
600 | * aggregate disk stat collector. Uses the same stats that the sysfs | |
601 | * entries do, above, but makes them available through one seq_file. | |
602 | * Watching a few disks may be efficient through sysfs, but watching | |
603 | * all of them will be more efficient through this interface. | |
604 | * | |
605 | * The output looks suspiciously like /proc/partitions with a bunch of | |
606 | * extra fields. | |
607 | */ | |
608 | ||
609 | /* iterator */ | |
610 | static void *diskstats_start(struct seq_file *part, loff_t *pos) | |
611 | { | |
612 | loff_t k = *pos; | |
613 | struct list_head *p; | |
614 | ||
58383af6 | 615 | mutex_lock(&block_subsys_lock); |
1da177e4 LT |
616 | list_for_each(p, &block_subsys.kset.list) |
617 | if (!k--) | |
618 | return list_entry(p, struct gendisk, kobj.entry); | |
619 | return NULL; | |
620 | } | |
621 | ||
622 | static void *diskstats_next(struct seq_file *part, void *v, loff_t *pos) | |
623 | { | |
624 | struct list_head *p = ((struct gendisk *)v)->kobj.entry.next; | |
625 | ++*pos; | |
626 | return p==&block_subsys.kset.list ? NULL : | |
627 | list_entry(p, struct gendisk, kobj.entry); | |
628 | } | |
629 | ||
630 | static void diskstats_stop(struct seq_file *part, void *v) | |
631 | { | |
58383af6 | 632 | mutex_unlock(&block_subsys_lock); |
1da177e4 LT |
633 | } |
634 | ||
635 | static int diskstats_show(struct seq_file *s, void *v) | |
636 | { | |
637 | struct gendisk *gp = v; | |
638 | char buf[BDEVNAME_SIZE]; | |
639 | int n = 0; | |
640 | ||
641 | /* | |
642 | if (&sgp->kobj.entry == block_subsys.kset.list.next) | |
643 | seq_puts(s, "major minor name" | |
644 | " rio rmerge rsect ruse wio wmerge " | |
645 | "wsect wuse running use aveq" | |
646 | "\n\n"); | |
647 | */ | |
648 | ||
649 | preempt_disable(); | |
650 | disk_round_stats(gp); | |
651 | preempt_enable(); | |
652 | seq_printf(s, "%4d %4d %s %u %u %llu %u %u %u %llu %u %u %u %u\n", | |
653 | gp->major, n + gp->first_minor, disk_name(gp, n, buf), | |
a362357b JA |
654 | disk_stat_read(gp, ios[0]), disk_stat_read(gp, merges[0]), |
655 | (unsigned long long)disk_stat_read(gp, sectors[0]), | |
656 | jiffies_to_msecs(disk_stat_read(gp, ticks[0])), | |
657 | disk_stat_read(gp, ios[1]), disk_stat_read(gp, merges[1]), | |
658 | (unsigned long long)disk_stat_read(gp, sectors[1]), | |
659 | jiffies_to_msecs(disk_stat_read(gp, ticks[1])), | |
1da177e4 LT |
660 | gp->in_flight, |
661 | jiffies_to_msecs(disk_stat_read(gp, io_ticks)), | |
662 | jiffies_to_msecs(disk_stat_read(gp, time_in_queue))); | |
663 | ||
664 | /* now show all non-0 size partitions of it */ | |
665 | for (n = 0; n < gp->minors - 1; n++) { | |
666 | struct hd_struct *hd = gp->part[n]; | |
667 | ||
668 | if (hd && hd->nr_sects) | |
669 | seq_printf(s, "%4d %4d %s %u %u %u %u\n", | |
670 | gp->major, n + gp->first_minor + 1, | |
671 | disk_name(gp, n + 1, buf), | |
a362357b JA |
672 | hd->ios[0], hd->sectors[0], |
673 | hd->ios[1], hd->sectors[1]); | |
1da177e4 LT |
674 | } |
675 | ||
676 | return 0; | |
677 | } | |
678 | ||
679 | struct seq_operations diskstats_op = { | |
680 | .start = diskstats_start, | |
681 | .next = diskstats_next, | |
682 | .stop = diskstats_stop, | |
683 | .show = diskstats_show | |
684 | }; | |
685 | ||
1da177e4 LT |
686 | struct gendisk *alloc_disk(int minors) |
687 | { | |
1946089a CL |
688 | return alloc_disk_node(minors, -1); |
689 | } | |
690 | ||
691 | struct gendisk *alloc_disk_node(int minors, int node_id) | |
692 | { | |
693 | struct gendisk *disk; | |
694 | ||
695 | disk = kmalloc_node(sizeof(struct gendisk), GFP_KERNEL, node_id); | |
1da177e4 LT |
696 | if (disk) { |
697 | memset(disk, 0, sizeof(struct gendisk)); | |
698 | if (!init_disk_stats(disk)) { | |
699 | kfree(disk); | |
700 | return NULL; | |
701 | } | |
702 | if (minors > 1) { | |
703 | int size = (minors - 1) * sizeof(struct hd_struct *); | |
1946089a | 704 | disk->part = kmalloc_node(size, GFP_KERNEL, node_id); |
1da177e4 LT |
705 | if (!disk->part) { |
706 | kfree(disk); | |
707 | return NULL; | |
708 | } | |
709 | memset(disk->part, 0, size); | |
710 | } | |
711 | disk->minors = minors; | |
712 | kobj_set_kset_s(disk,block_subsys); | |
713 | kobject_init(&disk->kobj); | |
714 | rand_initialize_disk(disk); | |
715 | } | |
716 | return disk; | |
717 | } | |
718 | ||
719 | EXPORT_SYMBOL(alloc_disk); | |
1946089a | 720 | EXPORT_SYMBOL(alloc_disk_node); |
1da177e4 LT |
721 | |
722 | struct kobject *get_disk(struct gendisk *disk) | |
723 | { | |
724 | struct module *owner; | |
725 | struct kobject *kobj; | |
726 | ||
727 | if (!disk->fops) | |
728 | return NULL; | |
729 | owner = disk->fops->owner; | |
730 | if (owner && !try_module_get(owner)) | |
731 | return NULL; | |
732 | kobj = kobject_get(&disk->kobj); | |
733 | if (kobj == NULL) { | |
734 | module_put(owner); | |
735 | return NULL; | |
736 | } | |
737 | return kobj; | |
738 | ||
739 | } | |
740 | ||
741 | EXPORT_SYMBOL(get_disk); | |
742 | ||
743 | void put_disk(struct gendisk *disk) | |
744 | { | |
745 | if (disk) | |
746 | kobject_put(&disk->kobj); | |
747 | } | |
748 | ||
749 | EXPORT_SYMBOL(put_disk); | |
750 | ||
751 | void set_device_ro(struct block_device *bdev, int flag) | |
752 | { | |
753 | if (bdev->bd_contains != bdev) | |
754 | bdev->bd_part->policy = flag; | |
755 | else | |
756 | bdev->bd_disk->policy = flag; | |
757 | } | |
758 | ||
759 | EXPORT_SYMBOL(set_device_ro); | |
760 | ||
761 | void set_disk_ro(struct gendisk *disk, int flag) | |
762 | { | |
763 | int i; | |
764 | disk->policy = flag; | |
765 | for (i = 0; i < disk->minors - 1; i++) | |
766 | if (disk->part[i]) disk->part[i]->policy = flag; | |
767 | } | |
768 | ||
769 | EXPORT_SYMBOL(set_disk_ro); | |
770 | ||
771 | int bdev_read_only(struct block_device *bdev) | |
772 | { | |
773 | if (!bdev) | |
774 | return 0; | |
775 | else if (bdev->bd_contains != bdev) | |
776 | return bdev->bd_part->policy; | |
777 | else | |
778 | return bdev->bd_disk->policy; | |
779 | } | |
780 | ||
781 | EXPORT_SYMBOL(bdev_read_only); | |
782 | ||
783 | int invalidate_partition(struct gendisk *disk, int index) | |
784 | { | |
785 | int res = 0; | |
786 | struct block_device *bdev = bdget_disk(disk, index); | |
787 | if (bdev) { | |
2ef41634 CH |
788 | fsync_bdev(bdev); |
789 | res = __invalidate_device(bdev); | |
1da177e4 LT |
790 | bdput(bdev); |
791 | } | |
792 | return res; | |
793 | } | |
794 | ||
795 | EXPORT_SYMBOL(invalidate_partition); |