blob: 4e5e7493f6764e8f3a03b62e40bd40b724d15880 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * gendisk handling
3 */
4
Linus Torvalds1da177e2005-04-16 15:20:36 -07005#include <linux/module.h>
6#include <linux/fs.h>
7#include <linux/genhd.h>
Andrew Mortonb446b602007-02-20 13:57:48 -08008#include <linux/kdev_t.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -07009#include <linux/kernel.h>
10#include <linux/blkdev.h>
11#include <linux/init.h>
12#include <linux/spinlock.h>
Alexey Dobriyanf5009752008-10-04 23:53:21 +040013#include <linux/proc_fs.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070014#include <linux/seq_file.h>
15#include <linux/slab.h>
16#include <linux/kmod.h>
17#include <linux/kobj_map.h>
Christoph Hellwig2ef41632005-05-05 16:15:59 -070018#include <linux/buffer_head.h>
Jes Sorensen58383af2006-02-06 14:12:43 -080019#include <linux/mutex.h>
Tejun Heobcce3de2008-08-25 19:47:22 +090020#include <linux/idr.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070021
Adrian Bunkff889722008-03-04 11:23:45 +010022#include "blk.h"
23
Kay Sieversedfaa7c2007-05-21 22:08:01 +020024static DEFINE_MUTEX(block_class_lock);
25#ifndef CONFIG_SYSFS_DEPRECATED
26struct kobject *block_depr;
27#endif
Linus Torvalds1da177e2005-04-16 15:20:36 -070028
Tejun Heobcce3de2008-08-25 19:47:22 +090029/* for extended dynamic devt allocation, currently only one major is used */
30#define MAX_EXT_DEVT (1 << MINORBITS)
31
32/* For extended devt allocation. ext_devt_mutex prevents look up
33 * results from going away underneath its user.
34 */
35static DEFINE_MUTEX(ext_devt_mutex);
36static DEFINE_IDR(ext_devt_idr);
37
Adrian Bunk1826ead2008-03-04 11:23:46 +010038static struct device_type disk_type;
39
Tejun Heoe71bf0d2008-09-03 09:03:02 +020040/**
41 * disk_get_part - get partition
42 * @disk: disk to look partition from
43 * @partno: partition number
44 *
45 * Look for partition @partno from @disk. If found, increment
46 * reference count and return it.
47 *
48 * CONTEXT:
49 * Don't care.
50 *
51 * RETURNS:
52 * Pointer to the found partition on success, NULL if not found.
53 */
54struct hd_struct *disk_get_part(struct gendisk *disk, int partno)
55{
Tejun Heo540eed52008-08-25 19:56:15 +090056 struct hd_struct *part = NULL;
57 struct disk_part_tbl *ptbl;
Tejun Heoe71bf0d2008-09-03 09:03:02 +020058
Tejun Heo540eed52008-08-25 19:56:15 +090059 if (unlikely(partno < 0))
Tejun Heoe71bf0d2008-09-03 09:03:02 +020060 return NULL;
Tejun Heo540eed52008-08-25 19:56:15 +090061
Tejun Heoe71bf0d2008-09-03 09:03:02 +020062 rcu_read_lock();
Tejun Heo540eed52008-08-25 19:56:15 +090063
64 ptbl = rcu_dereference(disk->part_tbl);
65 if (likely(partno < ptbl->len)) {
66 part = rcu_dereference(ptbl->part[partno]);
67 if (part)
68 get_device(part_to_dev(part));
69 }
70
Tejun Heoe71bf0d2008-09-03 09:03:02 +020071 rcu_read_unlock();
72
73 return part;
74}
75EXPORT_SYMBOL_GPL(disk_get_part);
76
77/**
78 * disk_part_iter_init - initialize partition iterator
79 * @piter: iterator to initialize
80 * @disk: disk to iterate over
81 * @flags: DISK_PITER_* flags
82 *
83 * Initialize @piter so that it iterates over partitions of @disk.
84 *
85 * CONTEXT:
86 * Don't care.
87 */
88void disk_part_iter_init(struct disk_part_iter *piter, struct gendisk *disk,
89 unsigned int flags)
90{
Tejun Heo540eed52008-08-25 19:56:15 +090091 struct disk_part_tbl *ptbl;
92
93 rcu_read_lock();
94 ptbl = rcu_dereference(disk->part_tbl);
95
Tejun Heoe71bf0d2008-09-03 09:03:02 +020096 piter->disk = disk;
97 piter->part = NULL;
98
99 if (flags & DISK_PITER_REVERSE)
Tejun Heo540eed52008-08-25 19:56:15 +0900100 piter->idx = ptbl->len - 1;
Tejun Heob5d0b9d2008-09-03 09:06:42 +0200101 else if (flags & DISK_PITER_INCL_PART0)
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200102 piter->idx = 0;
Tejun Heob5d0b9d2008-09-03 09:06:42 +0200103 else
104 piter->idx = 1;
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200105
106 piter->flags = flags;
Tejun Heo540eed52008-08-25 19:56:15 +0900107
108 rcu_read_unlock();
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200109}
110EXPORT_SYMBOL_GPL(disk_part_iter_init);
111
112/**
113 * disk_part_iter_next - proceed iterator to the next partition and return it
114 * @piter: iterator of interest
115 *
116 * Proceed @piter to the next partition and return it.
117 *
118 * CONTEXT:
119 * Don't care.
120 */
121struct hd_struct *disk_part_iter_next(struct disk_part_iter *piter)
122{
Tejun Heo540eed52008-08-25 19:56:15 +0900123 struct disk_part_tbl *ptbl;
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200124 int inc, end;
125
126 /* put the last partition */
127 disk_put_part(piter->part);
128 piter->part = NULL;
129
Tejun Heo540eed52008-08-25 19:56:15 +0900130 /* get part_tbl */
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200131 rcu_read_lock();
Tejun Heo540eed52008-08-25 19:56:15 +0900132 ptbl = rcu_dereference(piter->disk->part_tbl);
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200133
134 /* determine iteration parameters */
135 if (piter->flags & DISK_PITER_REVERSE) {
136 inc = -1;
Tejun Heob5d0b9d2008-09-03 09:06:42 +0200137 if (piter->flags & DISK_PITER_INCL_PART0)
138 end = -1;
139 else
140 end = 0;
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200141 } else {
142 inc = 1;
Tejun Heo540eed52008-08-25 19:56:15 +0900143 end = ptbl->len;
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200144 }
145
146 /* iterate to the next partition */
147 for (; piter->idx != end; piter->idx += inc) {
148 struct hd_struct *part;
149
Tejun Heo540eed52008-08-25 19:56:15 +0900150 part = rcu_dereference(ptbl->part[piter->idx]);
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200151 if (!part)
152 continue;
153 if (!(piter->flags & DISK_PITER_INCL_EMPTY) && !part->nr_sects)
154 continue;
155
Tejun Heoed9e1982008-08-25 19:56:05 +0900156 get_device(part_to_dev(part));
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200157 piter->part = part;
158 piter->idx += inc;
159 break;
160 }
161
162 rcu_read_unlock();
163
164 return piter->part;
165}
166EXPORT_SYMBOL_GPL(disk_part_iter_next);
167
168/**
169 * disk_part_iter_exit - finish up partition iteration
170 * @piter: iter of interest
171 *
172 * Called when iteration is over. Cleans up @piter.
173 *
174 * CONTEXT:
175 * Don't care.
176 */
177void disk_part_iter_exit(struct disk_part_iter *piter)
178{
179 disk_put_part(piter->part);
180 piter->part = NULL;
181}
182EXPORT_SYMBOL_GPL(disk_part_iter_exit);
183
184/**
185 * disk_map_sector_rcu - map sector to partition
186 * @disk: gendisk of interest
187 * @sector: sector to map
188 *
189 * Find out which partition @sector maps to on @disk. This is
190 * primarily used for stats accounting.
191 *
192 * CONTEXT:
193 * RCU read locked. The returned partition pointer is valid only
194 * while preemption is disabled.
195 *
196 * RETURNS:
Tejun Heo074a7ac2008-08-25 19:56:14 +0900197 * Found partition on success, part0 is returned if no partition matches
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200198 */
199struct hd_struct *disk_map_sector_rcu(struct gendisk *disk, sector_t sector)
200{
Tejun Heo540eed52008-08-25 19:56:15 +0900201 struct disk_part_tbl *ptbl;
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200202 int i;
203
Tejun Heo540eed52008-08-25 19:56:15 +0900204 ptbl = rcu_dereference(disk->part_tbl);
205
206 for (i = 1; i < ptbl->len; i++) {
207 struct hd_struct *part = rcu_dereference(ptbl->part[i]);
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200208
209 if (part && part->start_sect <= sector &&
210 sector < part->start_sect + part->nr_sects)
211 return part;
212 }
Tejun Heo074a7ac2008-08-25 19:56:14 +0900213 return &disk->part0;
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200214}
215EXPORT_SYMBOL_GPL(disk_map_sector_rcu);
216
Linus Torvalds1da177e2005-04-16 15:20:36 -0700217/*
218 * Can be deleted altogether. Later.
219 *
220 */
221static struct blk_major_name {
222 struct blk_major_name *next;
223 int major;
224 char name[16];
Joe Korty68eef3b2006-03-31 02:30:32 -0800225} *major_names[BLKDEV_MAJOR_HASH_SIZE];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700226
227/* index in the above - for now: assume no multimajor ranges */
228static inline int major_to_index(int major)
229{
Joe Korty68eef3b2006-03-31 02:30:32 -0800230 return major % BLKDEV_MAJOR_HASH_SIZE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700231}
232
Joe Korty68eef3b2006-03-31 02:30:32 -0800233#ifdef CONFIG_PROC_FS
Tejun Heocf771cb2008-09-03 09:01:09 +0200234void blkdev_show(struct seq_file *seqf, off_t offset)
Neil Horman7170be52006-01-14 13:20:38 -0800235{
Joe Korty68eef3b2006-03-31 02:30:32 -0800236 struct blk_major_name *dp;
Neil Horman7170be52006-01-14 13:20:38 -0800237
Joe Korty68eef3b2006-03-31 02:30:32 -0800238 if (offset < BLKDEV_MAJOR_HASH_SIZE) {
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200239 mutex_lock(&block_class_lock);
Joe Korty68eef3b2006-03-31 02:30:32 -0800240 for (dp = major_names[offset]; dp; dp = dp->next)
Tejun Heocf771cb2008-09-03 09:01:09 +0200241 seq_printf(seqf, "%3d %s\n", dp->major, dp->name);
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200242 mutex_unlock(&block_class_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700243 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700244}
Joe Korty68eef3b2006-03-31 02:30:32 -0800245#endif /* CONFIG_PROC_FS */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700246
247int register_blkdev(unsigned int major, const char *name)
248{
249 struct blk_major_name **n, *p;
250 int index, ret = 0;
251
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200252 mutex_lock(&block_class_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700253
254 /* temporary */
255 if (major == 0) {
256 for (index = ARRAY_SIZE(major_names)-1; index > 0; index--) {
257 if (major_names[index] == NULL)
258 break;
259 }
260
261 if (index == 0) {
262 printk("register_blkdev: failed to get major for %s\n",
263 name);
264 ret = -EBUSY;
265 goto out;
266 }
267 major = index;
268 ret = major;
269 }
270
271 p = kmalloc(sizeof(struct blk_major_name), GFP_KERNEL);
272 if (p == NULL) {
273 ret = -ENOMEM;
274 goto out;
275 }
276
277 p->major = major;
278 strlcpy(p->name, name, sizeof(p->name));
279 p->next = NULL;
280 index = major_to_index(major);
281
282 for (n = &major_names[index]; *n; n = &(*n)->next) {
283 if ((*n)->major == major)
284 break;
285 }
286 if (!*n)
287 *n = p;
288 else
289 ret = -EBUSY;
290
291 if (ret < 0) {
292 printk("register_blkdev: cannot get major %d for %s\n",
293 major, name);
294 kfree(p);
295 }
296out:
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200297 mutex_unlock(&block_class_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700298 return ret;
299}
300
301EXPORT_SYMBOL(register_blkdev);
302
Akinobu Mitaf4480242007-07-17 04:03:47 -0700303void unregister_blkdev(unsigned int major, const char *name)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700304{
305 struct blk_major_name **n;
306 struct blk_major_name *p = NULL;
307 int index = major_to_index(major);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700308
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200309 mutex_lock(&block_class_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700310 for (n = &major_names[index]; *n; n = &(*n)->next)
311 if ((*n)->major == major)
312 break;
Akinobu Mita294462a2007-07-17 04:03:45 -0700313 if (!*n || strcmp((*n)->name, name)) {
314 WARN_ON(1);
Akinobu Mita294462a2007-07-17 04:03:45 -0700315 } else {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700316 p = *n;
317 *n = p->next;
318 }
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200319 mutex_unlock(&block_class_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700320 kfree(p);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700321}
322
323EXPORT_SYMBOL(unregister_blkdev);
324
325static struct kobj_map *bdev_map;
326
Tejun Heobcce3de2008-08-25 19:47:22 +0900327/**
Tejun Heo870d6652008-08-25 19:47:25 +0900328 * blk_mangle_minor - scatter minor numbers apart
329 * @minor: minor number to mangle
330 *
331 * Scatter consecutively allocated @minor number apart if MANGLE_DEVT
332 * is enabled. Mangling twice gives the original value.
333 *
334 * RETURNS:
335 * Mangled value.
336 *
337 * CONTEXT:
338 * Don't care.
339 */
340static int blk_mangle_minor(int minor)
341{
342#ifdef CONFIG_DEBUG_BLOCK_EXT_DEVT
343 int i;
344
345 for (i = 0; i < MINORBITS / 2; i++) {
346 int low = minor & (1 << i);
347 int high = minor & (1 << (MINORBITS - 1 - i));
348 int distance = MINORBITS - 1 - 2 * i;
349
350 minor ^= low | high; /* clear both bits */
351 low <<= distance; /* swap the positions */
352 high >>= distance;
353 minor |= low | high; /* and set */
354 }
355#endif
356 return minor;
357}
358
359/**
Tejun Heobcce3de2008-08-25 19:47:22 +0900360 * blk_alloc_devt - allocate a dev_t for a partition
361 * @part: partition to allocate dev_t for
Tejun Heobcce3de2008-08-25 19:47:22 +0900362 * @devt: out parameter for resulting dev_t
363 *
364 * Allocate a dev_t for block device.
365 *
366 * RETURNS:
367 * 0 on success, allocated dev_t is returned in *@devt. -errno on
368 * failure.
369 *
370 * CONTEXT:
371 * Might sleep.
372 */
373int blk_alloc_devt(struct hd_struct *part, dev_t *devt)
374{
375 struct gendisk *disk = part_to_disk(part);
376 int idx, rc;
377
378 /* in consecutive minor range? */
379 if (part->partno < disk->minors) {
380 *devt = MKDEV(disk->major, disk->first_minor + part->partno);
381 return 0;
382 }
383
384 /* allocate ext devt */
385 do {
386 if (!idr_pre_get(&ext_devt_idr, GFP_KERNEL))
387 return -ENOMEM;
388 rc = idr_get_new(&ext_devt_idr, part, &idx);
389 } while (rc == -EAGAIN);
390
391 if (rc)
392 return rc;
393
394 if (idx > MAX_EXT_DEVT) {
395 idr_remove(&ext_devt_idr, idx);
396 return -EBUSY;
397 }
398
Tejun Heo870d6652008-08-25 19:47:25 +0900399 *devt = MKDEV(BLOCK_EXT_MAJOR, blk_mangle_minor(idx));
Tejun Heobcce3de2008-08-25 19:47:22 +0900400 return 0;
401}
402
403/**
404 * blk_free_devt - free a dev_t
405 * @devt: dev_t to free
406 *
407 * Free @devt which was allocated using blk_alloc_devt().
408 *
409 * CONTEXT:
410 * Might sleep.
411 */
412void blk_free_devt(dev_t devt)
413{
414 might_sleep();
415
416 if (devt == MKDEV(0, 0))
417 return;
418
419 if (MAJOR(devt) == BLOCK_EXT_MAJOR) {
420 mutex_lock(&ext_devt_mutex);
Tejun Heo870d6652008-08-25 19:47:25 +0900421 idr_remove(&ext_devt_idr, blk_mangle_minor(MINOR(devt)));
Tejun Heobcce3de2008-08-25 19:47:22 +0900422 mutex_unlock(&ext_devt_mutex);
423 }
424}
425
Tejun Heo1f014292008-08-25 19:47:23 +0900426static char *bdevt_str(dev_t devt, char *buf)
427{
428 if (MAJOR(devt) <= 0xff && MINOR(devt) <= 0xff) {
429 char tbuf[BDEVT_SIZE];
430 snprintf(tbuf, BDEVT_SIZE, "%02x%02x", MAJOR(devt), MINOR(devt));
431 snprintf(buf, BDEVT_SIZE, "%-9s", tbuf);
432 } else
433 snprintf(buf, BDEVT_SIZE, "%03x:%05x", MAJOR(devt), MINOR(devt));
434
435 return buf;
436}
437
Linus Torvalds1da177e2005-04-16 15:20:36 -0700438/*
439 * Register device numbers dev..(dev+range-1)
440 * range must be nonzero
441 * The hash chain is sorted on range, so that subranges can override.
442 */
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200443void blk_register_region(dev_t devt, unsigned long range, struct module *module,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700444 struct kobject *(*probe)(dev_t, int *, void *),
445 int (*lock)(dev_t, void *), void *data)
446{
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200447 kobj_map(bdev_map, devt, range, module, probe, lock, data);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700448}
449
450EXPORT_SYMBOL(blk_register_region);
451
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200452void blk_unregister_region(dev_t devt, unsigned long range)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700453{
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200454 kobj_unmap(bdev_map, devt, range);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700455}
456
457EXPORT_SYMBOL(blk_unregister_region);
458
Tejun Heocf771cb2008-09-03 09:01:09 +0200459static struct kobject *exact_match(dev_t devt, int *partno, void *data)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700460{
461 struct gendisk *p = data;
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200462
Tejun Heoed9e1982008-08-25 19:56:05 +0900463 return &disk_to_dev(p)->kobj;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700464}
465
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200466static int exact_lock(dev_t devt, void *data)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700467{
468 struct gendisk *p = data;
469
470 if (!get_disk(p))
471 return -1;
472 return 0;
473}
474
475/**
476 * add_disk - add partitioning information to kernel list
477 * @disk: per-device partitioning information
478 *
479 * This function registers the partitioning information in @disk
480 * with the kernel.
Tejun Heo3e1a7ff2008-08-25 19:56:17 +0900481 *
482 * FIXME: error handling
Linus Torvalds1da177e2005-04-16 15:20:36 -0700483 */
484void add_disk(struct gendisk *disk)
485{
Peter Zijlstracf0ca9f2008-04-30 00:54:32 -0700486 struct backing_dev_info *bdi;
Tejun Heo3e1a7ff2008-08-25 19:56:17 +0900487 dev_t devt;
Greg Kroah-Hartman6ffeea72008-05-22 17:21:08 -0400488 int retval;
Peter Zijlstracf0ca9f2008-04-30 00:54:32 -0700489
Tejun Heo3e1a7ff2008-08-25 19:56:17 +0900490 /* minors == 0 indicates to use ext devt from part0 and should
491 * be accompanied with EXT_DEVT flag. Make sure all
492 * parameters make sense.
493 */
494 WARN_ON(disk->minors && !(disk->major || disk->first_minor));
495 WARN_ON(!disk->minors && !(disk->flags & GENHD_FL_EXT_DEVT));
496
Linus Torvalds1da177e2005-04-16 15:20:36 -0700497 disk->flags |= GENHD_FL_UP;
Tejun Heo3e1a7ff2008-08-25 19:56:17 +0900498
499 retval = blk_alloc_devt(&disk->part0, &devt);
500 if (retval) {
501 WARN_ON(1);
502 return;
503 }
504 disk_to_dev(disk)->devt = devt;
505
506 /* ->major and ->first_minor aren't supposed to be
507 * dereferenced from here on, but set them just in case.
508 */
509 disk->major = MAJOR(devt);
510 disk->first_minor = MINOR(devt);
511
Tejun Heof331c022008-09-03 09:01:48 +0200512 blk_register_region(disk_devt(disk), disk->minors, NULL,
513 exact_match, exact_lock, disk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700514 register_disk(disk);
515 blk_register_queue(disk);
Peter Zijlstracf0ca9f2008-04-30 00:54:32 -0700516
517 bdi = &disk->queue->backing_dev_info;
Tejun Heof331c022008-09-03 09:01:48 +0200518 bdi_register_dev(bdi, disk_devt(disk));
Tejun Heoed9e1982008-08-25 19:56:05 +0900519 retval = sysfs_create_link(&disk_to_dev(disk)->kobj, &bdi->dev->kobj,
520 "bdi");
Greg Kroah-Hartman6ffeea72008-05-22 17:21:08 -0400521 WARN_ON(retval);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700522}
523
524EXPORT_SYMBOL(add_disk);
525EXPORT_SYMBOL(del_gendisk); /* in partitions/check.c */
526
527void unlink_gendisk(struct gendisk *disk)
528{
Tejun Heoed9e1982008-08-25 19:56:05 +0900529 sysfs_remove_link(&disk_to_dev(disk)->kobj, "bdi");
Peter Zijlstracf0ca9f2008-04-30 00:54:32 -0700530 bdi_unregister(&disk->queue->backing_dev_info);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700531 blk_unregister_queue(disk);
Tejun Heof331c022008-09-03 09:01:48 +0200532 blk_unregister_region(disk_devt(disk), disk->minors);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700533}
534
Linus Torvalds1da177e2005-04-16 15:20:36 -0700535/**
536 * get_gendisk - get partitioning information for a given device
Randy Dunlap710027a2008-08-19 20:13:11 +0200537 * @devt: device to get partitioning information for
Randy Dunlap496aa8a2008-10-16 07:46:23 +0200538 * @partno: returned partition index
Linus Torvalds1da177e2005-04-16 15:20:36 -0700539 *
540 * This function gets the structure containing partitioning
Randy Dunlap710027a2008-08-19 20:13:11 +0200541 * information for the given device @devt.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700542 */
Tejun Heocf771cb2008-09-03 09:01:09 +0200543struct gendisk *get_gendisk(dev_t devt, int *partno)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700544{
Tejun Heobcce3de2008-08-25 19:47:22 +0900545 struct gendisk *disk = NULL;
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200546
Tejun Heobcce3de2008-08-25 19:47:22 +0900547 if (MAJOR(devt) != BLOCK_EXT_MAJOR) {
548 struct kobject *kobj;
549
550 kobj = kobj_lookup(bdev_map, devt, partno);
551 if (kobj)
552 disk = dev_to_disk(kobj_to_dev(kobj));
553 } else {
554 struct hd_struct *part;
555
556 mutex_lock(&ext_devt_mutex);
Tejun Heo870d6652008-08-25 19:47:25 +0900557 part = idr_find(&ext_devt_idr, blk_mangle_minor(MINOR(devt)));
Tejun Heobcce3de2008-08-25 19:47:22 +0900558 if (part && get_disk(part_to_disk(part))) {
559 *partno = part->partno;
560 disk = part_to_disk(part);
561 }
562 mutex_unlock(&ext_devt_mutex);
563 }
564
565 return disk;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700566}
567
Tejun Heof331c022008-09-03 09:01:48 +0200568/**
569 * bdget_disk - do bdget() by gendisk and partition number
570 * @disk: gendisk of interest
571 * @partno: partition number
572 *
573 * Find partition @partno from @disk, do bdget() on it.
574 *
575 * CONTEXT:
576 * Don't care.
577 *
578 * RETURNS:
579 * Resulting block_device on success, NULL on failure.
580 */
Harvey Harrisonaeb3d3a2008-08-28 09:27:42 +0200581struct block_device *bdget_disk(struct gendisk *disk, int partno)
Tejun Heof331c022008-09-03 09:01:48 +0200582{
Tejun Heo548b10e2008-08-29 09:01:47 +0200583 struct hd_struct *part;
584 struct block_device *bdev = NULL;
Tejun Heof331c022008-09-03 09:01:48 +0200585
Tejun Heo548b10e2008-08-29 09:01:47 +0200586 part = disk_get_part(disk, partno);
Tejun Heo2bbedcb2008-08-29 11:41:51 +0200587 if (part)
Tejun Heo548b10e2008-08-29 09:01:47 +0200588 bdev = bdget(part_devt(part));
589 disk_put_part(part);
Tejun Heof331c022008-09-03 09:01:48 +0200590
Tejun Heo548b10e2008-08-29 09:01:47 +0200591 return bdev;
Tejun Heof331c022008-09-03 09:01:48 +0200592}
593EXPORT_SYMBOL(bdget_disk);
594
Dave Gilbertdd2a3452007-05-09 02:33:24 -0700595/*
596 * print a full list of all partitions - intended for places where the root
597 * filesystem can't be mounted and thus to give the victim some idea of what
598 * went wrong
599 */
600void __init printk_all_partitions(void)
601{
Tejun Heodef4e382008-09-03 08:57:12 +0200602 struct class_dev_iter iter;
603 struct device *dev;
604
605 class_dev_iter_init(&iter, &block_class, NULL, &disk_type);
606 while ((dev = class_dev_iter_next(&iter))) {
607 struct gendisk *disk = dev_to_disk(dev);
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200608 struct disk_part_iter piter;
609 struct hd_struct *part;
Tejun Heo1f014292008-08-25 19:47:23 +0900610 char name_buf[BDEVNAME_SIZE];
611 char devt_buf[BDEVT_SIZE];
Tejun Heodef4e382008-09-03 08:57:12 +0200612
613 /*
614 * Don't show empty devices or things that have been
615 * surpressed
616 */
617 if (get_capacity(disk) == 0 ||
618 (disk->flags & GENHD_FL_SUPPRESS_PARTITION_INFO))
619 continue;
620
621 /*
622 * Note, unlike /proc/partitions, I am showing the
623 * numbers in hex - the same format as the root=
624 * option takes.
625 */
Tejun Heo074a7ac2008-08-25 19:56:14 +0900626 disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0);
627 while ((part = disk_part_iter_next(&piter))) {
628 bool is_part0 = part == &disk->part0;
Tejun Heodef4e382008-09-03 08:57:12 +0200629
Tejun Heo074a7ac2008-08-25 19:56:14 +0900630 printk("%s%s %10llu %s", is_part0 ? "" : " ",
Tejun Heo1f014292008-08-25 19:47:23 +0900631 bdevt_str(part_devt(part), devt_buf),
Tejun Heof331c022008-09-03 09:01:48 +0200632 (unsigned long long)part->nr_sects >> 1,
Tejun Heo1f014292008-08-25 19:47:23 +0900633 disk_name(disk, part->partno, name_buf));
Tejun Heo074a7ac2008-08-25 19:56:14 +0900634 if (is_part0) {
635 if (disk->driverfs_dev != NULL &&
636 disk->driverfs_dev->driver != NULL)
637 printk(" driver: %s\n",
638 disk->driverfs_dev->driver->name);
639 else
640 printk(" (driver?)\n");
641 } else
642 printk("\n");
643 }
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200644 disk_part_iter_exit(&piter);
Tejun Heodef4e382008-09-03 08:57:12 +0200645 }
646 class_dev_iter_exit(&iter);
Dave Gilbertdd2a3452007-05-09 02:33:24 -0700647}
648
Linus Torvalds1da177e2005-04-16 15:20:36 -0700649#ifdef CONFIG_PROC_FS
650/* iterator */
Tejun Heodef4e382008-09-03 08:57:12 +0200651static void *disk_seqf_start(struct seq_file *seqf, loff_t *pos)
Greg Kroah-Hartman68c4d4a2008-05-22 17:21:08 -0400652{
Tejun Heodef4e382008-09-03 08:57:12 +0200653 loff_t skip = *pos;
654 struct class_dev_iter *iter;
655 struct device *dev;
Greg Kroah-Hartman68c4d4a2008-05-22 17:21:08 -0400656
Harvey Harrisonaeb3d3a2008-08-28 09:27:42 +0200657 iter = kmalloc(sizeof(*iter), GFP_KERNEL);
Tejun Heodef4e382008-09-03 08:57:12 +0200658 if (!iter)
659 return ERR_PTR(-ENOMEM);
660
661 seqf->private = iter;
662 class_dev_iter_init(iter, &block_class, NULL, &disk_type);
663 do {
664 dev = class_dev_iter_next(iter);
665 if (!dev)
666 return NULL;
667 } while (skip--);
668
669 return dev_to_disk(dev);
Greg Kroah-Hartman68c4d4a2008-05-22 17:21:08 -0400670}
671
Tejun Heodef4e382008-09-03 08:57:12 +0200672static void *disk_seqf_next(struct seq_file *seqf, void *v, loff_t *pos)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700673{
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200674 struct device *dev;
Greg Kroah-Hartman66c64af2008-05-22 17:21:08 -0400675
Tejun Heodef4e382008-09-03 08:57:12 +0200676 (*pos)++;
677 dev = class_dev_iter_next(seqf->private);
Tejun Heo2ac3cee2008-09-03 08:53:37 +0200678 if (dev)
Greg Kroah-Hartman68c4d4a2008-05-22 17:21:08 -0400679 return dev_to_disk(dev);
Tejun Heo2ac3cee2008-09-03 08:53:37 +0200680
Linus Torvalds1da177e2005-04-16 15:20:36 -0700681 return NULL;
682}
683
Tejun Heodef4e382008-09-03 08:57:12 +0200684static void disk_seqf_stop(struct seq_file *seqf, void *v)
Greg Kroah-Hartman27f30252008-05-22 17:21:08 -0400685{
Tejun Heodef4e382008-09-03 08:57:12 +0200686 struct class_dev_iter *iter = seqf->private;
Greg Kroah-Hartman27f30252008-05-22 17:21:08 -0400687
Tejun Heodef4e382008-09-03 08:57:12 +0200688 /* stop is called even after start failed :-( */
689 if (iter) {
690 class_dev_iter_exit(iter);
691 kfree(iter);
Kay Sievers5c0ef6d2008-08-16 14:30:30 +0200692 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700693}
694
Tejun Heodef4e382008-09-03 08:57:12 +0200695static void *show_partition_start(struct seq_file *seqf, loff_t *pos)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700696{
Tejun Heodef4e382008-09-03 08:57:12 +0200697 static void *p;
698
699 p = disk_seqf_start(seqf, pos);
Tejun Heo243294d2008-09-04 09:17:31 +0200700 if (!IS_ERR(p) && p && !*pos)
Tejun Heodef4e382008-09-03 08:57:12 +0200701 seq_puts(seqf, "major minor #blocks name\n\n");
702 return p;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700703}
704
Tejun Heocf771cb2008-09-03 09:01:09 +0200705static int show_partition(struct seq_file *seqf, void *v)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700706{
707 struct gendisk *sgp = v;
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200708 struct disk_part_iter piter;
709 struct hd_struct *part;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700710 char buf[BDEVNAME_SIZE];
711
Linus Torvalds1da177e2005-04-16 15:20:36 -0700712 /* Don't show non-partitionable removeable devices or empty devices */
Tejun Heob5d0b9d2008-09-03 09:06:42 +0200713 if (!get_capacity(sgp) || (!disk_partitionable(sgp) &&
Tejun Heof331c022008-09-03 09:01:48 +0200714 (sgp->flags & GENHD_FL_REMOVABLE)))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700715 return 0;
716 if (sgp->flags & GENHD_FL_SUPPRESS_PARTITION_INFO)
717 return 0;
718
719 /* show the full disk and all non-0 size partitions of it */
Tejun Heo074a7ac2008-08-25 19:56:14 +0900720 disk_part_iter_init(&piter, sgp, DISK_PITER_INCL_PART0);
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200721 while ((part = disk_part_iter_next(&piter)))
Tejun Heo1f014292008-08-25 19:47:23 +0900722 seq_printf(seqf, "%4d %7d %10llu %s\n",
Tejun Heof331c022008-09-03 09:01:48 +0200723 MAJOR(part_devt(part)), MINOR(part_devt(part)),
724 (unsigned long long)part->nr_sects >> 1,
725 disk_name(sgp, part->partno, buf));
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200726 disk_part_iter_exit(&piter);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700727
728 return 0;
729}
730
Alexey Dobriyanf5009752008-10-04 23:53:21 +0400731static const struct seq_operations partitions_op = {
Tejun Heodef4e382008-09-03 08:57:12 +0200732 .start = show_partition_start,
733 .next = disk_seqf_next,
734 .stop = disk_seqf_stop,
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200735 .show = show_partition
Linus Torvalds1da177e2005-04-16 15:20:36 -0700736};
Alexey Dobriyanf5009752008-10-04 23:53:21 +0400737
738static int partitions_open(struct inode *inode, struct file *file)
739{
740 return seq_open(file, &partitions_op);
741}
742
743static const struct file_operations proc_partitions_operations = {
744 .open = partitions_open,
745 .read = seq_read,
746 .llseek = seq_lseek,
747 .release = seq_release,
748};
Linus Torvalds1da177e2005-04-16 15:20:36 -0700749#endif
750
751
Tejun Heocf771cb2008-09-03 09:01:09 +0200752static struct kobject *base_probe(dev_t devt, int *partno, void *data)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700753{
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200754 if (request_module("block-major-%d-%d", MAJOR(devt), MINOR(devt)) > 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700755 /* Make old-style 2.4 aliases work */
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200756 request_module("block-major-%d", MAJOR(devt));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700757 return NULL;
758}
759
760static int __init genhd_device_init(void)
761{
Dan Williamse105b8b2008-04-21 10:51:07 -0700762 int error;
763
764 block_class.dev_kobj = sysfs_dev_block_kobj;
765 error = class_register(&block_class);
Roland McGrathee27a552008-03-11 17:13:15 -0700766 if (unlikely(error))
767 return error;
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200768 bdev_map = kobj_map_init(base_probe, &block_class_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700769 blk_dev_init();
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200770
771#ifndef CONFIG_SYSFS_DEPRECATED
772 /* create top-level block dir */
773 block_depr = kobject_create_and_add("block", NULL);
774#endif
Greg Kroah-Hartman830d3cf2007-11-06 10:36:58 -0800775 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700776}
777
778subsys_initcall(genhd_device_init);
779
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200780static ssize_t disk_range_show(struct device *dev,
781 struct device_attribute *attr, char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700782{
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200783 struct gendisk *disk = dev_to_disk(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700784
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200785 return sprintf(buf, "%d\n", disk->minors);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700786}
787
Tejun Heo1f014292008-08-25 19:47:23 +0900788static ssize_t disk_ext_range_show(struct device *dev,
789 struct device_attribute *attr, char *buf)
790{
791 struct gendisk *disk = dev_to_disk(dev);
792
Tejun Heob5d0b9d2008-09-03 09:06:42 +0200793 return sprintf(buf, "%d\n", disk_max_parts(disk));
Tejun Heo1f014292008-08-25 19:47:23 +0900794}
795
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200796static ssize_t disk_removable_show(struct device *dev,
797 struct device_attribute *attr, char *buf)
Kay Sieversa7fd6702005-10-01 14:49:43 +0200798{
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200799 struct gendisk *disk = dev_to_disk(dev);
Kay Sieversa7fd6702005-10-01 14:49:43 +0200800
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200801 return sprintf(buf, "%d\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700802 (disk->flags & GENHD_FL_REMOVABLE ? 1 : 0));
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200803}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700804
Kay Sievers1c9ce522008-06-13 09:41:00 +0200805static ssize_t disk_ro_show(struct device *dev,
806 struct device_attribute *attr, char *buf)
807{
808 struct gendisk *disk = dev_to_disk(dev);
809
Tejun Heob7db9952008-08-25 19:56:10 +0900810 return sprintf(buf, "%d\n", get_disk_ro(disk) ? 1 : 0);
Kay Sievers1c9ce522008-06-13 09:41:00 +0200811}
812
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200813static ssize_t disk_capability_show(struct device *dev,
814 struct device_attribute *attr, char *buf)
Kristen Carlson Accardi86ce18d2007-05-23 13:57:38 -0700815{
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200816 struct gendisk *disk = dev_to_disk(dev);
817
818 return sprintf(buf, "%x\n", disk->flags);
Kristen Carlson Accardi86ce18d2007-05-23 13:57:38 -0700819}
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200820
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200821static DEVICE_ATTR(range, S_IRUGO, disk_range_show, NULL);
Tejun Heo1f014292008-08-25 19:47:23 +0900822static DEVICE_ATTR(ext_range, S_IRUGO, disk_ext_range_show, NULL);
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200823static DEVICE_ATTR(removable, S_IRUGO, disk_removable_show, NULL);
Kay Sievers1c9ce522008-06-13 09:41:00 +0200824static DEVICE_ATTR(ro, S_IRUGO, disk_ro_show, NULL);
Tejun Heoe5610522008-08-25 19:56:09 +0900825static DEVICE_ATTR(size, S_IRUGO, part_size_show, NULL);
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200826static DEVICE_ATTR(capability, S_IRUGO, disk_capability_show, NULL);
Tejun Heo074a7ac2008-08-25 19:56:14 +0900827static DEVICE_ATTR(stat, S_IRUGO, part_stat_show, NULL);
Akinobu Mitac17bb492006-12-08 02:39:46 -0800828#ifdef CONFIG_FAIL_MAKE_REQUEST
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200829static struct device_attribute dev_attr_fail =
Tejun Heoeddb2e22008-08-25 19:56:13 +0900830 __ATTR(make-it-fail, S_IRUGO|S_IWUSR, part_fail_show, part_fail_store);
Akinobu Mitac17bb492006-12-08 02:39:46 -0800831#endif
Jens Axboe581d4e22008-09-14 05:56:33 -0700832#ifdef CONFIG_FAIL_IO_TIMEOUT
833static struct device_attribute dev_attr_fail_timeout =
834 __ATTR(io-timeout-fail, S_IRUGO|S_IWUSR, part_timeout_show,
835 part_timeout_store);
836#endif
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200837
838static struct attribute *disk_attrs[] = {
839 &dev_attr_range.attr,
Tejun Heo1f014292008-08-25 19:47:23 +0900840 &dev_attr_ext_range.attr,
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200841 &dev_attr_removable.attr,
Kay Sievers1c9ce522008-06-13 09:41:00 +0200842 &dev_attr_ro.attr,
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200843 &dev_attr_size.attr,
844 &dev_attr_capability.attr,
845 &dev_attr_stat.attr,
846#ifdef CONFIG_FAIL_MAKE_REQUEST
847 &dev_attr_fail.attr,
848#endif
Jens Axboe581d4e22008-09-14 05:56:33 -0700849#ifdef CONFIG_FAIL_IO_TIMEOUT
850 &dev_attr_fail_timeout.attr,
851#endif
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200852 NULL
Linus Torvalds1da177e2005-04-16 15:20:36 -0700853};
854
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200855static struct attribute_group disk_attr_group = {
856 .attrs = disk_attrs,
857};
858
859static struct attribute_group *disk_attr_groups[] = {
860 &disk_attr_group,
861 NULL
862};
863
Tejun Heo540eed52008-08-25 19:56:15 +0900864static void disk_free_ptbl_rcu_cb(struct rcu_head *head)
865{
866 struct disk_part_tbl *ptbl =
867 container_of(head, struct disk_part_tbl, rcu_head);
868
869 kfree(ptbl);
870}
871
872/**
873 * disk_replace_part_tbl - replace disk->part_tbl in RCU-safe way
874 * @disk: disk to replace part_tbl for
875 * @new_ptbl: new part_tbl to install
876 *
877 * Replace disk->part_tbl with @new_ptbl in RCU-safe way. The
878 * original ptbl is freed using RCU callback.
879 *
880 * LOCKING:
881 * Matching bd_mutx locked.
882 */
883static void disk_replace_part_tbl(struct gendisk *disk,
884 struct disk_part_tbl *new_ptbl)
885{
886 struct disk_part_tbl *old_ptbl = disk->part_tbl;
887
888 rcu_assign_pointer(disk->part_tbl, new_ptbl);
889 if (old_ptbl)
890 call_rcu(&old_ptbl->rcu_head, disk_free_ptbl_rcu_cb);
891}
892
893/**
894 * disk_expand_part_tbl - expand disk->part_tbl
895 * @disk: disk to expand part_tbl for
896 * @partno: expand such that this partno can fit in
897 *
898 * Expand disk->part_tbl such that @partno can fit in. disk->part_tbl
899 * uses RCU to allow unlocked dereferencing for stats and other stuff.
900 *
901 * LOCKING:
902 * Matching bd_mutex locked, might sleep.
903 *
904 * RETURNS:
905 * 0 on success, -errno on failure.
906 */
907int disk_expand_part_tbl(struct gendisk *disk, int partno)
908{
909 struct disk_part_tbl *old_ptbl = disk->part_tbl;
910 struct disk_part_tbl *new_ptbl;
911 int len = old_ptbl ? old_ptbl->len : 0;
912 int target = partno + 1;
913 size_t size;
914 int i;
915
916 /* disk_max_parts() is zero during initialization, ignore if so */
917 if (disk_max_parts(disk) && target > disk_max_parts(disk))
918 return -EINVAL;
919
920 if (target <= len)
921 return 0;
922
923 size = sizeof(*new_ptbl) + target * sizeof(new_ptbl->part[0]);
924 new_ptbl = kzalloc_node(size, GFP_KERNEL, disk->node_id);
925 if (!new_ptbl)
926 return -ENOMEM;
927
928 INIT_RCU_HEAD(&new_ptbl->rcu_head);
929 new_ptbl->len = target;
930
931 for (i = 0; i < len; i++)
932 rcu_assign_pointer(new_ptbl->part[i], old_ptbl->part[i]);
933
934 disk_replace_part_tbl(disk, new_ptbl);
935 return 0;
936}
937
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200938static void disk_release(struct device *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700939{
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200940 struct gendisk *disk = dev_to_disk(dev);
941
Linus Torvalds1da177e2005-04-16 15:20:36 -0700942 kfree(disk->random);
Tejun Heo540eed52008-08-25 19:56:15 +0900943 disk_replace_part_tbl(disk, NULL);
Tejun Heo074a7ac2008-08-25 19:56:14 +0900944 free_part_stats(&disk->part0);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700945 kfree(disk);
946}
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200947struct class block_class = {
948 .name = "block",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700949};
950
Adrian Bunk1826ead2008-03-04 11:23:46 +0100951static struct device_type disk_type = {
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200952 .name = "disk",
953 .groups = disk_attr_groups,
954 .release = disk_release,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700955};
956
Randy Dunlapa6e2ba82008-05-23 09:44:11 -0700957#ifdef CONFIG_PROC_FS
Tejun Heocf771cb2008-09-03 09:01:09 +0200958/*
959 * aggregate disk stat collector. Uses the same stats that the sysfs
960 * entries do, above, but makes them available through one seq_file.
961 *
962 * The output looks suspiciously like /proc/partitions with a bunch of
963 * extra fields.
964 */
965static int diskstats_show(struct seq_file *seqf, void *v)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700966{
967 struct gendisk *gp = v;
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200968 struct disk_part_iter piter;
969 struct hd_struct *hd;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700970 char buf[BDEVNAME_SIZE];
Tejun Heoc9959052008-08-25 19:47:21 +0900971 int cpu;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700972
973 /*
Tejun Heoed9e1982008-08-25 19:56:05 +0900974 if (&disk_to_dev(gp)->kobj.entry == block_class.devices.next)
Tejun Heocf771cb2008-09-03 09:01:09 +0200975 seq_puts(seqf, "major minor name"
Linus Torvalds1da177e2005-04-16 15:20:36 -0700976 " rio rmerge rsect ruse wio wmerge "
977 "wsect wuse running use aveq"
978 "\n\n");
979 */
980
Tejun Heo074a7ac2008-08-25 19:56:14 +0900981 disk_part_iter_init(&piter, gp, DISK_PITER_INCL_PART0);
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200982 while ((hd = disk_part_iter_next(&piter))) {
Tejun Heo074a7ac2008-08-25 19:56:14 +0900983 cpu = part_stat_lock();
Tejun Heoc9959052008-08-25 19:47:21 +0900984 part_round_stats(cpu, hd);
Tejun Heo074a7ac2008-08-25 19:56:14 +0900985 part_stat_unlock();
Tejun Heo1f014292008-08-25 19:47:23 +0900986 seq_printf(seqf, "%4d %7d %s %lu %lu %llu "
Jerome Marchand28f39d52008-02-08 11:04:56 +0100987 "%u %lu %lu %llu %u %u %u %u\n",
Tejun Heof331c022008-09-03 09:01:48 +0200988 MAJOR(part_devt(hd)), MINOR(part_devt(hd)),
989 disk_name(gp, hd->partno, buf),
Jerome Marchand28f39d52008-02-08 11:04:56 +0100990 part_stat_read(hd, ios[0]),
991 part_stat_read(hd, merges[0]),
992 (unsigned long long)part_stat_read(hd, sectors[0]),
993 jiffies_to_msecs(part_stat_read(hd, ticks[0])),
994 part_stat_read(hd, ios[1]),
995 part_stat_read(hd, merges[1]),
996 (unsigned long long)part_stat_read(hd, sectors[1]),
997 jiffies_to_msecs(part_stat_read(hd, ticks[1])),
998 hd->in_flight,
999 jiffies_to_msecs(part_stat_read(hd, io_ticks)),
1000 jiffies_to_msecs(part_stat_read(hd, time_in_queue))
1001 );
Linus Torvalds1da177e2005-04-16 15:20:36 -07001002 }
Tejun Heoe71bf0d2008-09-03 09:03:02 +02001003 disk_part_iter_exit(&piter);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001004
1005 return 0;
1006}
1007
Alexey Dobriyan31d85ab2008-10-06 12:55:38 +04001008static const struct seq_operations diskstats_op = {
Tejun Heodef4e382008-09-03 08:57:12 +02001009 .start = disk_seqf_start,
1010 .next = disk_seqf_next,
1011 .stop = disk_seqf_stop,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001012 .show = diskstats_show
1013};
Alexey Dobriyanf5009752008-10-04 23:53:21 +04001014
Alexey Dobriyan31d85ab2008-10-06 12:55:38 +04001015static int diskstats_open(struct inode *inode, struct file *file)
1016{
1017 return seq_open(file, &diskstats_op);
1018}
1019
1020static const struct file_operations proc_diskstats_operations = {
1021 .open = diskstats_open,
1022 .read = seq_read,
1023 .llseek = seq_lseek,
1024 .release = seq_release,
1025};
1026
Alexey Dobriyanf5009752008-10-04 23:53:21 +04001027static int __init proc_genhd_init(void)
1028{
Alexey Dobriyan31d85ab2008-10-06 12:55:38 +04001029 proc_create("diskstats", 0, NULL, &proc_diskstats_operations);
Alexey Dobriyanf5009752008-10-04 23:53:21 +04001030 proc_create("partitions", 0, NULL, &proc_partitions_operations);
1031 return 0;
1032}
1033module_init(proc_genhd_init);
Randy Dunlapa6e2ba82008-05-23 09:44:11 -07001034#endif /* CONFIG_PROC_FS */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001035
Kristen Carlson Accardi8ce7ad72007-05-23 13:57:38 -07001036static void media_change_notify_thread(struct work_struct *work)
1037{
1038 struct gendisk *gd = container_of(work, struct gendisk, async_notify);
1039 char event[] = "MEDIA_CHANGE=1";
1040 char *envp[] = { event, NULL };
1041
1042 /*
1043 * set enviroment vars to indicate which event this is for
1044 * so that user space will know to go check the media status.
1045 */
Tejun Heoed9e1982008-08-25 19:56:05 +09001046 kobject_uevent_env(&disk_to_dev(gd)->kobj, KOBJ_CHANGE, envp);
Kristen Carlson Accardi8ce7ad72007-05-23 13:57:38 -07001047 put_device(gd->driverfs_dev);
1048}
1049
Adrian Bunk1826ead2008-03-04 11:23:46 +01001050#if 0
Kristen Carlson Accardi8ce7ad72007-05-23 13:57:38 -07001051void genhd_media_change_notify(struct gendisk *disk)
1052{
1053 get_device(disk->driverfs_dev);
1054 schedule_work(&disk->async_notify);
1055}
1056EXPORT_SYMBOL_GPL(genhd_media_change_notify);
Adrian Bunk1826ead2008-03-04 11:23:46 +01001057#endif /* 0 */
Kristen Carlson Accardi8ce7ad72007-05-23 13:57:38 -07001058
Tejun Heocf771cb2008-09-03 09:01:09 +02001059dev_t blk_lookup_devt(const char *name, int partno)
Kay Sieversedfaa7c2007-05-21 22:08:01 +02001060{
Kay Sieversedfaa7c2007-05-21 22:08:01 +02001061 dev_t devt = MKDEV(0, 0);
Tejun Heodef4e382008-09-03 08:57:12 +02001062 struct class_dev_iter iter;
1063 struct device *dev;
Kay Sieversedfaa7c2007-05-21 22:08:01 +02001064
Tejun Heodef4e382008-09-03 08:57:12 +02001065 class_dev_iter_init(&iter, &block_class, NULL, &disk_type);
1066 while ((dev = class_dev_iter_next(&iter))) {
1067 struct gendisk *disk = dev_to_disk(dev);
Tejun Heo548b10e2008-08-29 09:01:47 +02001068 struct hd_struct *part;
Tejun Heodef4e382008-09-03 08:57:12 +02001069
Tejun Heof331c022008-09-03 09:01:48 +02001070 if (strcmp(dev->bus_id, name))
1071 continue;
Tejun Heof331c022008-09-03 09:01:48 +02001072
Tejun Heo548b10e2008-08-29 09:01:47 +02001073 part = disk_get_part(disk, partno);
Tejun Heo2bbedcb2008-08-29 11:41:51 +02001074 if (part) {
Tejun Heof331c022008-09-03 09:01:48 +02001075 devt = part_devt(part);
Tejun Heoe71bf0d2008-09-03 09:03:02 +02001076 disk_put_part(part);
Tejun Heo548b10e2008-08-29 09:01:47 +02001077 break;
Tejun Heodef4e382008-09-03 08:57:12 +02001078 }
Tejun Heo548b10e2008-08-29 09:01:47 +02001079 disk_put_part(part);
Kay Sievers5c0ef6d2008-08-16 14:30:30 +02001080 }
Tejun Heodef4e382008-09-03 08:57:12 +02001081 class_dev_iter_exit(&iter);
Kay Sieversedfaa7c2007-05-21 22:08:01 +02001082 return devt;
1083}
Kay Sieversedfaa7c2007-05-21 22:08:01 +02001084EXPORT_SYMBOL(blk_lookup_devt);
1085
Linus Torvalds1da177e2005-04-16 15:20:36 -07001086struct gendisk *alloc_disk(int minors)
1087{
Christoph Lameter19460892005-06-23 00:08:19 -07001088 return alloc_disk_node(minors, -1);
1089}
Tejun Heo689d6fa2008-08-25 19:56:16 +09001090EXPORT_SYMBOL(alloc_disk);
Christoph Lameter19460892005-06-23 00:08:19 -07001091
1092struct gendisk *alloc_disk_node(int minors, int node_id)
1093{
1094 struct gendisk *disk;
1095
Christoph Lameter94f60302007-07-17 04:03:29 -07001096 disk = kmalloc_node(sizeof(struct gendisk),
1097 GFP_KERNEL | __GFP_ZERO, node_id);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001098 if (disk) {
Tejun Heo074a7ac2008-08-25 19:56:14 +09001099 if (!init_part_stats(&disk->part0)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001100 kfree(disk);
1101 return NULL;
1102 }
Tejun Heo540eed52008-08-25 19:56:15 +09001103 if (disk_expand_part_tbl(disk, 0)) {
1104 free_part_stats(&disk->part0);
Tejun Heob5d0b9d2008-09-03 09:06:42 +02001105 kfree(disk);
1106 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001107 }
Tejun Heo540eed52008-08-25 19:56:15 +09001108 disk->part_tbl->part[0] = &disk->part0;
Tejun Heob5d0b9d2008-09-03 09:06:42 +02001109
Linus Torvalds1da177e2005-04-16 15:20:36 -07001110 disk->minors = minors;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001111 rand_initialize_disk(disk);
Tejun Heoed9e1982008-08-25 19:56:05 +09001112 disk_to_dev(disk)->class = &block_class;
1113 disk_to_dev(disk)->type = &disk_type;
1114 device_initialize(disk_to_dev(disk));
Kristen Carlson Accardi8ce7ad72007-05-23 13:57:38 -07001115 INIT_WORK(&disk->async_notify,
1116 media_change_notify_thread);
Tejun Heo540eed52008-08-25 19:56:15 +09001117 disk->node_id = node_id;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001118 }
1119 return disk;
1120}
Christoph Lameter19460892005-06-23 00:08:19 -07001121EXPORT_SYMBOL(alloc_disk_node);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001122
1123struct kobject *get_disk(struct gendisk *disk)
1124{
1125 struct module *owner;
1126 struct kobject *kobj;
1127
1128 if (!disk->fops)
1129 return NULL;
1130 owner = disk->fops->owner;
1131 if (owner && !try_module_get(owner))
1132 return NULL;
Tejun Heoed9e1982008-08-25 19:56:05 +09001133 kobj = kobject_get(&disk_to_dev(disk)->kobj);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001134 if (kobj == NULL) {
1135 module_put(owner);
1136 return NULL;
1137 }
1138 return kobj;
1139
1140}
1141
1142EXPORT_SYMBOL(get_disk);
1143
1144void put_disk(struct gendisk *disk)
1145{
1146 if (disk)
Tejun Heoed9e1982008-08-25 19:56:05 +09001147 kobject_put(&disk_to_dev(disk)->kobj);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001148}
1149
1150EXPORT_SYMBOL(put_disk);
1151
1152void set_device_ro(struct block_device *bdev, int flag)
1153{
Tejun Heob7db9952008-08-25 19:56:10 +09001154 bdev->bd_part->policy = flag;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001155}
1156
1157EXPORT_SYMBOL(set_device_ro);
1158
1159void set_disk_ro(struct gendisk *disk, int flag)
1160{
Tejun Heoe71bf0d2008-09-03 09:03:02 +02001161 struct disk_part_iter piter;
1162 struct hd_struct *part;
1163
Tejun Heob7db9952008-08-25 19:56:10 +09001164 disk_part_iter_init(&piter, disk,
1165 DISK_PITER_INCL_EMPTY | DISK_PITER_INCL_PART0);
Tejun Heoe71bf0d2008-09-03 09:03:02 +02001166 while ((part = disk_part_iter_next(&piter)))
1167 part->policy = flag;
1168 disk_part_iter_exit(&piter);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001169}
1170
1171EXPORT_SYMBOL(set_disk_ro);
1172
1173int bdev_read_only(struct block_device *bdev)
1174{
1175 if (!bdev)
1176 return 0;
Tejun Heob7db9952008-08-25 19:56:10 +09001177 return bdev->bd_part->policy;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001178}
1179
1180EXPORT_SYMBOL(bdev_read_only);
1181
Tejun Heocf771cb2008-09-03 09:01:09 +02001182int invalidate_partition(struct gendisk *disk, int partno)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001183{
1184 int res = 0;
Tejun Heocf771cb2008-09-03 09:01:09 +02001185 struct block_device *bdev = bdget_disk(disk, partno);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001186 if (bdev) {
Christoph Hellwig2ef41632005-05-05 16:15:59 -07001187 fsync_bdev(bdev);
1188 res = __invalidate_device(bdev);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001189 bdput(bdev);
1190 }
1191 return res;
1192}
1193
1194EXPORT_SYMBOL(invalidate_partition);