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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>
Tejun Heo66114ca2015-05-22 17:13:32 -040011#include <linux/backing-dev.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070012#include <linux/init.h>
13#include <linux/spinlock.h>
Alexey Dobriyanf5009752008-10-04 23:53:21 +040014#include <linux/proc_fs.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070015#include <linux/seq_file.h>
16#include <linux/slab.h>
17#include <linux/kmod.h>
18#include <linux/kobj_map.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>
Tejun Heo77ea8872010-12-08 20:57:37 +010021#include <linux/log2.h>
Ming Lei25e823c2013-02-22 16:34:13 -080022#include <linux/pm_runtime.h>
Vishal Verma99e66082016-01-09 08:36:51 -080023#include <linux/badblocks.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070024
Adrian Bunkff889722008-03-04 11:23:45 +010025#include "blk.h"
26
Kay Sieversedfaa7c2007-05-21 22:08:01 +020027static DEFINE_MUTEX(block_class_lock);
Kay Sieversedfaa7c2007-05-21 22:08:01 +020028struct kobject *block_depr;
Linus Torvalds1da177e2005-04-16 15:20:36 -070029
Tejun Heobcce3de2008-08-25 19:47:22 +090030/* for extended dynamic devt allocation, currently only one major is used */
Tejun Heoce23bba2013-02-27 17:03:56 -080031#define NR_EXT_DEVT (1 << MINORBITS)
Tejun Heobcce3de2008-08-25 19:47:22 +090032
Keith Busch2da78092014-08-26 09:05:36 -060033/* For extended devt allocation. ext_devt_lock prevents look up
Tejun Heobcce3de2008-08-25 19:47:22 +090034 * results from going away underneath its user.
35 */
Keith Busch2da78092014-08-26 09:05:36 -060036static DEFINE_SPINLOCK(ext_devt_lock);
Tejun Heobcce3de2008-08-25 19:47:22 +090037static DEFINE_IDR(ext_devt_idr);
38
Adrian Bunk1826ead2008-03-04 11:23:46 +010039static struct device_type disk_type;
40
Derek Basehore12c2bdb2012-12-18 12:27:20 -080041static void disk_check_events(struct disk_events *ev,
42 unsigned int *clearing_ptr);
Stanislaw Gruszka9f53d2fe2012-03-02 10:43:28 +010043static void disk_alloc_events(struct gendisk *disk);
Tejun Heo77ea8872010-12-08 20:57:37 +010044static void disk_add_events(struct gendisk *disk);
45static void disk_del_events(struct gendisk *disk);
46static void disk_release_events(struct gendisk *disk);
47
Tejun Heoe71bf0d2008-09-03 09:03:02 +020048/**
49 * disk_get_part - get partition
50 * @disk: disk to look partition from
51 * @partno: partition number
52 *
53 * Look for partition @partno from @disk. If found, increment
54 * reference count and return it.
55 *
56 * CONTEXT:
57 * Don't care.
58 *
59 * RETURNS:
60 * Pointer to the found partition on success, NULL if not found.
61 */
62struct hd_struct *disk_get_part(struct gendisk *disk, int partno)
63{
Tejun Heo540eed52008-08-25 19:56:15 +090064 struct hd_struct *part = NULL;
65 struct disk_part_tbl *ptbl;
Tejun Heoe71bf0d2008-09-03 09:03:02 +020066
Tejun Heo540eed52008-08-25 19:56:15 +090067 if (unlikely(partno < 0))
Tejun Heoe71bf0d2008-09-03 09:03:02 +020068 return NULL;
Tejun Heo540eed52008-08-25 19:56:15 +090069
Tejun Heoe71bf0d2008-09-03 09:03:02 +020070 rcu_read_lock();
Tejun Heo540eed52008-08-25 19:56:15 +090071
72 ptbl = rcu_dereference(disk->part_tbl);
73 if (likely(partno < ptbl->len)) {
74 part = rcu_dereference(ptbl->part[partno]);
75 if (part)
76 get_device(part_to_dev(part));
77 }
78
Tejun Heoe71bf0d2008-09-03 09:03:02 +020079 rcu_read_unlock();
80
81 return part;
82}
83EXPORT_SYMBOL_GPL(disk_get_part);
84
85/**
86 * disk_part_iter_init - initialize partition iterator
87 * @piter: iterator to initialize
88 * @disk: disk to iterate over
89 * @flags: DISK_PITER_* flags
90 *
91 * Initialize @piter so that it iterates over partitions of @disk.
92 *
93 * CONTEXT:
94 * Don't care.
95 */
96void disk_part_iter_init(struct disk_part_iter *piter, struct gendisk *disk,
97 unsigned int flags)
98{
Tejun Heo540eed52008-08-25 19:56:15 +090099 struct disk_part_tbl *ptbl;
100
101 rcu_read_lock();
102 ptbl = rcu_dereference(disk->part_tbl);
103
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200104 piter->disk = disk;
105 piter->part = NULL;
106
107 if (flags & DISK_PITER_REVERSE)
Tejun Heo540eed52008-08-25 19:56:15 +0900108 piter->idx = ptbl->len - 1;
Tejun Heo71982a42009-04-17 08:34:48 +0200109 else if (flags & (DISK_PITER_INCL_PART0 | DISK_PITER_INCL_EMPTY_PART0))
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200110 piter->idx = 0;
Tejun Heob5d0b9d2008-09-03 09:06:42 +0200111 else
112 piter->idx = 1;
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200113
114 piter->flags = flags;
Tejun Heo540eed52008-08-25 19:56:15 +0900115
116 rcu_read_unlock();
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200117}
118EXPORT_SYMBOL_GPL(disk_part_iter_init);
119
120/**
121 * disk_part_iter_next - proceed iterator to the next partition and return it
122 * @piter: iterator of interest
123 *
124 * Proceed @piter to the next partition and return it.
125 *
126 * CONTEXT:
127 * Don't care.
128 */
129struct hd_struct *disk_part_iter_next(struct disk_part_iter *piter)
130{
Tejun Heo540eed52008-08-25 19:56:15 +0900131 struct disk_part_tbl *ptbl;
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200132 int inc, end;
133
134 /* put the last partition */
135 disk_put_part(piter->part);
136 piter->part = NULL;
137
Tejun Heo540eed52008-08-25 19:56:15 +0900138 /* get part_tbl */
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200139 rcu_read_lock();
Tejun Heo540eed52008-08-25 19:56:15 +0900140 ptbl = rcu_dereference(piter->disk->part_tbl);
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200141
142 /* determine iteration parameters */
143 if (piter->flags & DISK_PITER_REVERSE) {
144 inc = -1;
Tejun Heo71982a42009-04-17 08:34:48 +0200145 if (piter->flags & (DISK_PITER_INCL_PART0 |
146 DISK_PITER_INCL_EMPTY_PART0))
Tejun Heob5d0b9d2008-09-03 09:06:42 +0200147 end = -1;
148 else
149 end = 0;
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200150 } else {
151 inc = 1;
Tejun Heo540eed52008-08-25 19:56:15 +0900152 end = ptbl->len;
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200153 }
154
155 /* iterate to the next partition */
156 for (; piter->idx != end; piter->idx += inc) {
157 struct hd_struct *part;
158
Tejun Heo540eed52008-08-25 19:56:15 +0900159 part = rcu_dereference(ptbl->part[piter->idx]);
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200160 if (!part)
161 continue;
Vivek Goyalc83f6bf2012-08-01 12:24:18 +0200162 if (!part_nr_sects_read(part) &&
Tejun Heo71982a42009-04-17 08:34:48 +0200163 !(piter->flags & DISK_PITER_INCL_EMPTY) &&
164 !(piter->flags & DISK_PITER_INCL_EMPTY_PART0 &&
165 piter->idx == 0))
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200166 continue;
167
Tejun Heoed9e1982008-08-25 19:56:05 +0900168 get_device(part_to_dev(part));
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200169 piter->part = part;
170 piter->idx += inc;
171 break;
172 }
173
174 rcu_read_unlock();
175
176 return piter->part;
177}
178EXPORT_SYMBOL_GPL(disk_part_iter_next);
179
180/**
181 * disk_part_iter_exit - finish up partition iteration
182 * @piter: iter of interest
183 *
184 * Called when iteration is over. Cleans up @piter.
185 *
186 * CONTEXT:
187 * Don't care.
188 */
189void disk_part_iter_exit(struct disk_part_iter *piter)
190{
191 disk_put_part(piter->part);
192 piter->part = NULL;
193}
194EXPORT_SYMBOL_GPL(disk_part_iter_exit);
195
Jens Axboea6f23652008-10-24 12:52:42 +0200196static inline int sector_in_part(struct hd_struct *part, sector_t sector)
197{
198 return part->start_sect <= sector &&
Vivek Goyalc83f6bf2012-08-01 12:24:18 +0200199 sector < part->start_sect + part_nr_sects_read(part);
Jens Axboea6f23652008-10-24 12:52:42 +0200200}
201
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200202/**
203 * disk_map_sector_rcu - map sector to partition
204 * @disk: gendisk of interest
205 * @sector: sector to map
206 *
207 * Find out which partition @sector maps to on @disk. This is
208 * primarily used for stats accounting.
209 *
210 * CONTEXT:
211 * RCU read locked. The returned partition pointer is valid only
212 * while preemption is disabled.
213 *
214 * RETURNS:
Tejun Heo074a7ac2008-08-25 19:56:14 +0900215 * Found partition on success, part0 is returned if no partition matches
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200216 */
217struct hd_struct *disk_map_sector_rcu(struct gendisk *disk, sector_t sector)
218{
Tejun Heo540eed52008-08-25 19:56:15 +0900219 struct disk_part_tbl *ptbl;
Jens Axboea6f23652008-10-24 12:52:42 +0200220 struct hd_struct *part;
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200221 int i;
222
Tejun Heo540eed52008-08-25 19:56:15 +0900223 ptbl = rcu_dereference(disk->part_tbl);
224
Jens Axboea6f23652008-10-24 12:52:42 +0200225 part = rcu_dereference(ptbl->last_lookup);
226 if (part && sector_in_part(part, sector))
227 return part;
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200228
Jens Axboea6f23652008-10-24 12:52:42 +0200229 for (i = 1; i < ptbl->len; i++) {
230 part = rcu_dereference(ptbl->part[i]);
231
232 if (part && sector_in_part(part, sector)) {
233 rcu_assign_pointer(ptbl->last_lookup, part);
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200234 return part;
Jens Axboea6f23652008-10-24 12:52:42 +0200235 }
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200236 }
Tejun Heo074a7ac2008-08-25 19:56:14 +0900237 return &disk->part0;
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200238}
239EXPORT_SYMBOL_GPL(disk_map_sector_rcu);
240
Linus Torvalds1da177e2005-04-16 15:20:36 -0700241/*
242 * Can be deleted altogether. Later.
243 *
244 */
245static struct blk_major_name {
246 struct blk_major_name *next;
247 int major;
248 char name[16];
Joe Korty68eef3b2006-03-31 02:30:32 -0800249} *major_names[BLKDEV_MAJOR_HASH_SIZE];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700250
251/* index in the above - for now: assume no multimajor ranges */
Yang Zhange61eb2e2010-12-17 09:00:18 +0100252static inline int major_to_index(unsigned major)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700253{
Joe Korty68eef3b2006-03-31 02:30:32 -0800254 return major % BLKDEV_MAJOR_HASH_SIZE;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700255}
256
Joe Korty68eef3b2006-03-31 02:30:32 -0800257#ifdef CONFIG_PROC_FS
Tejun Heocf771cb2008-09-03 09:01:09 +0200258void blkdev_show(struct seq_file *seqf, off_t offset)
Neil Horman7170be52006-01-14 13:20:38 -0800259{
Joe Korty68eef3b2006-03-31 02:30:32 -0800260 struct blk_major_name *dp;
Neil Horman7170be52006-01-14 13:20:38 -0800261
Joe Korty68eef3b2006-03-31 02:30:32 -0800262 if (offset < BLKDEV_MAJOR_HASH_SIZE) {
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200263 mutex_lock(&block_class_lock);
Joe Korty68eef3b2006-03-31 02:30:32 -0800264 for (dp = major_names[offset]; dp; dp = dp->next)
Tejun Heocf771cb2008-09-03 09:01:09 +0200265 seq_printf(seqf, "%3d %s\n", dp->major, dp->name);
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200266 mutex_unlock(&block_class_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700267 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700268}
Joe Korty68eef3b2006-03-31 02:30:32 -0800269#endif /* CONFIG_PROC_FS */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700270
Márton Németh9e8c0bc2009-02-20 08:12:51 +0100271/**
272 * register_blkdev - register a new block device
273 *
274 * @major: the requested major device number [1..255]. If @major=0, try to
275 * allocate any unused major number.
276 * @name: the name of the new block device as a zero terminated string
277 *
278 * The @name must be unique within the system.
279 *
280 * The return value depends on the @major input parameter.
281 * - if a major device number was requested in range [1..255] then the
282 * function returns zero on success, or a negative error code
283 * - if any unused major number was requested with @major=0 parameter
284 * then the return value is the allocated major number in range
285 * [1..255] or a negative error code otherwise
286 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700287int register_blkdev(unsigned int major, const char *name)
288{
289 struct blk_major_name **n, *p;
290 int index, ret = 0;
291
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200292 mutex_lock(&block_class_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700293
294 /* temporary */
295 if (major == 0) {
296 for (index = ARRAY_SIZE(major_names)-1; index > 0; index--) {
297 if (major_names[index] == NULL)
298 break;
299 }
300
301 if (index == 0) {
302 printk("register_blkdev: failed to get major for %s\n",
303 name);
304 ret = -EBUSY;
305 goto out;
306 }
307 major = index;
308 ret = major;
309 }
310
311 p = kmalloc(sizeof(struct blk_major_name), GFP_KERNEL);
312 if (p == NULL) {
313 ret = -ENOMEM;
314 goto out;
315 }
316
317 p->major = major;
318 strlcpy(p->name, name, sizeof(p->name));
319 p->next = NULL;
320 index = major_to_index(major);
321
322 for (n = &major_names[index]; *n; n = &(*n)->next) {
323 if ((*n)->major == major)
324 break;
325 }
326 if (!*n)
327 *n = p;
328 else
329 ret = -EBUSY;
330
331 if (ret < 0) {
332 printk("register_blkdev: cannot get major %d for %s\n",
333 major, name);
334 kfree(p);
335 }
336out:
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200337 mutex_unlock(&block_class_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700338 return ret;
339}
340
341EXPORT_SYMBOL(register_blkdev);
342
Akinobu Mitaf4480242007-07-17 04:03:47 -0700343void unregister_blkdev(unsigned int major, const char *name)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700344{
345 struct blk_major_name **n;
346 struct blk_major_name *p = NULL;
347 int index = major_to_index(major);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700348
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200349 mutex_lock(&block_class_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700350 for (n = &major_names[index]; *n; n = &(*n)->next)
351 if ((*n)->major == major)
352 break;
Akinobu Mita294462a2007-07-17 04:03:45 -0700353 if (!*n || strcmp((*n)->name, name)) {
354 WARN_ON(1);
Akinobu Mita294462a2007-07-17 04:03:45 -0700355 } else {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700356 p = *n;
357 *n = p->next;
358 }
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200359 mutex_unlock(&block_class_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700360 kfree(p);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700361}
362
363EXPORT_SYMBOL(unregister_blkdev);
364
365static struct kobj_map *bdev_map;
366
Tejun Heobcce3de2008-08-25 19:47:22 +0900367/**
Tejun Heo870d6652008-08-25 19:47:25 +0900368 * blk_mangle_minor - scatter minor numbers apart
369 * @minor: minor number to mangle
370 *
371 * Scatter consecutively allocated @minor number apart if MANGLE_DEVT
372 * is enabled. Mangling twice gives the original value.
373 *
374 * RETURNS:
375 * Mangled value.
376 *
377 * CONTEXT:
378 * Don't care.
379 */
380static int blk_mangle_minor(int minor)
381{
382#ifdef CONFIG_DEBUG_BLOCK_EXT_DEVT
383 int i;
384
385 for (i = 0; i < MINORBITS / 2; i++) {
386 int low = minor & (1 << i);
387 int high = minor & (1 << (MINORBITS - 1 - i));
388 int distance = MINORBITS - 1 - 2 * i;
389
390 minor ^= low | high; /* clear both bits */
391 low <<= distance; /* swap the positions */
392 high >>= distance;
393 minor |= low | high; /* and set */
394 }
395#endif
396 return minor;
397}
398
399/**
Tejun Heobcce3de2008-08-25 19:47:22 +0900400 * blk_alloc_devt - allocate a dev_t for a partition
401 * @part: partition to allocate dev_t for
Tejun Heobcce3de2008-08-25 19:47:22 +0900402 * @devt: out parameter for resulting dev_t
403 *
404 * Allocate a dev_t for block device.
405 *
406 * RETURNS:
407 * 0 on success, allocated dev_t is returned in *@devt. -errno on
408 * failure.
409 *
410 * CONTEXT:
411 * Might sleep.
412 */
413int blk_alloc_devt(struct hd_struct *part, dev_t *devt)
414{
415 struct gendisk *disk = part_to_disk(part);
Tejun Heobab998d2013-02-27 17:03:57 -0800416 int idx;
Tejun Heobcce3de2008-08-25 19:47:22 +0900417
418 /* in consecutive minor range? */
419 if (part->partno < disk->minors) {
420 *devt = MKDEV(disk->major, disk->first_minor + part->partno);
421 return 0;
422 }
423
424 /* allocate ext devt */
Keith Busch2da78092014-08-26 09:05:36 -0600425 idr_preload(GFP_KERNEL);
426
Dan Williams4d66e5e2015-06-10 23:47:14 -0400427 spin_lock_bh(&ext_devt_lock);
Keith Busch2da78092014-08-26 09:05:36 -0600428 idx = idr_alloc(&ext_devt_idr, part, 0, NR_EXT_DEVT, GFP_NOWAIT);
Dan Williams4d66e5e2015-06-10 23:47:14 -0400429 spin_unlock_bh(&ext_devt_lock);
Keith Busch2da78092014-08-26 09:05:36 -0600430
431 idr_preload_end();
Tejun Heobab998d2013-02-27 17:03:57 -0800432 if (idx < 0)
433 return idx == -ENOSPC ? -EBUSY : idx;
Tejun Heobcce3de2008-08-25 19:47:22 +0900434
Tejun Heo870d6652008-08-25 19:47:25 +0900435 *devt = MKDEV(BLOCK_EXT_MAJOR, blk_mangle_minor(idx));
Tejun Heobcce3de2008-08-25 19:47:22 +0900436 return 0;
437}
438
439/**
440 * blk_free_devt - free a dev_t
441 * @devt: dev_t to free
442 *
443 * Free @devt which was allocated using blk_alloc_devt().
444 *
445 * CONTEXT:
446 * Might sleep.
447 */
448void blk_free_devt(dev_t devt)
449{
Tejun Heobcce3de2008-08-25 19:47:22 +0900450 if (devt == MKDEV(0, 0))
451 return;
452
453 if (MAJOR(devt) == BLOCK_EXT_MAJOR) {
Dan Williams4d66e5e2015-06-10 23:47:14 -0400454 spin_lock_bh(&ext_devt_lock);
Tejun Heo870d6652008-08-25 19:47:25 +0900455 idr_remove(&ext_devt_idr, blk_mangle_minor(MINOR(devt)));
Dan Williams4d66e5e2015-06-10 23:47:14 -0400456 spin_unlock_bh(&ext_devt_lock);
Tejun Heobcce3de2008-08-25 19:47:22 +0900457 }
458}
459
Tejun Heo1f014292008-08-25 19:47:23 +0900460static char *bdevt_str(dev_t devt, char *buf)
461{
462 if (MAJOR(devt) <= 0xff && MINOR(devt) <= 0xff) {
463 char tbuf[BDEVT_SIZE];
464 snprintf(tbuf, BDEVT_SIZE, "%02x%02x", MAJOR(devt), MINOR(devt));
465 snprintf(buf, BDEVT_SIZE, "%-9s", tbuf);
466 } else
467 snprintf(buf, BDEVT_SIZE, "%03x:%05x", MAJOR(devt), MINOR(devt));
468
469 return buf;
470}
471
Linus Torvalds1da177e2005-04-16 15:20:36 -0700472/*
473 * Register device numbers dev..(dev+range-1)
474 * range must be nonzero
475 * The hash chain is sorted on range, so that subranges can override.
476 */
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200477void blk_register_region(dev_t devt, unsigned long range, struct module *module,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700478 struct kobject *(*probe)(dev_t, int *, void *),
479 int (*lock)(dev_t, void *), void *data)
480{
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200481 kobj_map(bdev_map, devt, range, module, probe, lock, data);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700482}
483
484EXPORT_SYMBOL(blk_register_region);
485
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200486void blk_unregister_region(dev_t devt, unsigned long range)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700487{
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200488 kobj_unmap(bdev_map, devt, range);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700489}
490
491EXPORT_SYMBOL(blk_unregister_region);
492
Tejun Heocf771cb2008-09-03 09:01:09 +0200493static struct kobject *exact_match(dev_t devt, int *partno, void *data)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700494{
495 struct gendisk *p = data;
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200496
Tejun Heoed9e1982008-08-25 19:56:05 +0900497 return &disk_to_dev(p)->kobj;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700498}
499
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200500static int exact_lock(dev_t devt, void *data)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700501{
502 struct gendisk *p = data;
503
504 if (!get_disk(p))
505 return -1;
506 return 0;
507}
508
Al Viro4752bc32011-09-16 00:21:54 -0400509static void register_disk(struct gendisk *disk)
Tejun Heod2bf1b62010-12-08 20:57:36 +0100510{
511 struct device *ddev = disk_to_dev(disk);
512 struct block_device *bdev;
513 struct disk_part_iter piter;
514 struct hd_struct *part;
515 int err;
516
517 ddev->parent = disk->driverfs_dev;
518
Kees Cookffc8b302013-07-03 15:01:14 -0700519 dev_set_name(ddev, "%s", disk->disk_name);
Tejun Heod2bf1b62010-12-08 20:57:36 +0100520
521 /* delay uevents, until we scanned partition table */
522 dev_set_uevent_suppress(ddev, 1);
523
524 if (device_add(ddev))
525 return;
526 if (!sysfs_deprecated) {
527 err = sysfs_create_link(block_depr, &ddev->kobj,
528 kobject_name(&ddev->kobj));
529 if (err) {
530 device_del(ddev);
531 return;
532 }
533 }
Ming Lei25e823c2013-02-22 16:34:13 -0800534
535 /*
536 * avoid probable deadlock caused by allocating memory with
537 * GFP_KERNEL in runtime_resume callback of its all ancestor
538 * devices
539 */
540 pm_runtime_set_memalloc_noio(ddev, true);
541
Tejun Heod2bf1b62010-12-08 20:57:36 +0100542 disk->part0.holder_dir = kobject_create_and_add("holders", &ddev->kobj);
543 disk->slave_dir = kobject_create_and_add("slaves", &ddev->kobj);
544
545 /* No minors to use for partitions */
Tejun Heod27769e2011-08-23 20:01:04 +0200546 if (!disk_part_scan_enabled(disk))
Tejun Heod2bf1b62010-12-08 20:57:36 +0100547 goto exit;
548
549 /* No such device (e.g., media were just removed) */
550 if (!get_capacity(disk))
551 goto exit;
552
553 bdev = bdget_disk(disk, 0);
554 if (!bdev)
555 goto exit;
556
557 bdev->bd_invalidated = 1;
558 err = blkdev_get(bdev, FMODE_READ, NULL);
559 if (err < 0)
560 goto exit;
561 blkdev_put(bdev, FMODE_READ);
562
563exit:
564 /* announce disk after possible partitions are created */
565 dev_set_uevent_suppress(ddev, 0);
566 kobject_uevent(&ddev->kobj, KOBJ_ADD);
567
568 /* announce possible partitions */
569 disk_part_iter_init(&piter, disk, 0);
570 while ((part = disk_part_iter_next(&piter)))
571 kobject_uevent(&part_to_dev(part)->kobj, KOBJ_ADD);
572 disk_part_iter_exit(&piter);
573}
574
Linus Torvalds1da177e2005-04-16 15:20:36 -0700575/**
576 * add_disk - add partitioning information to kernel list
577 * @disk: per-device partitioning information
578 *
579 * This function registers the partitioning information in @disk
580 * with the kernel.
Tejun Heo3e1a7ff2008-08-25 19:56:17 +0900581 *
582 * FIXME: error handling
Linus Torvalds1da177e2005-04-16 15:20:36 -0700583 */
584void add_disk(struct gendisk *disk)
585{
Peter Zijlstracf0ca9f2008-04-30 00:54:32 -0700586 struct backing_dev_info *bdi;
Tejun Heo3e1a7ff2008-08-25 19:56:17 +0900587 dev_t devt;
Greg Kroah-Hartman6ffeea72008-05-22 17:21:08 -0400588 int retval;
Peter Zijlstracf0ca9f2008-04-30 00:54:32 -0700589
Tejun Heo3e1a7ff2008-08-25 19:56:17 +0900590 /* minors == 0 indicates to use ext devt from part0 and should
591 * be accompanied with EXT_DEVT flag. Make sure all
592 * parameters make sense.
593 */
594 WARN_ON(disk->minors && !(disk->major || disk->first_minor));
595 WARN_ON(!disk->minors && !(disk->flags & GENHD_FL_EXT_DEVT));
596
Linus Torvalds1da177e2005-04-16 15:20:36 -0700597 disk->flags |= GENHD_FL_UP;
Tejun Heo3e1a7ff2008-08-25 19:56:17 +0900598
599 retval = blk_alloc_devt(&disk->part0, &devt);
600 if (retval) {
601 WARN_ON(1);
602 return;
603 }
604 disk_to_dev(disk)->devt = devt;
605
606 /* ->major and ->first_minor aren't supposed to be
607 * dereferenced from here on, but set them just in case.
608 */
609 disk->major = MAJOR(devt);
610 disk->first_minor = MINOR(devt);
611
Stanislaw Gruszka9f53d2fe2012-03-02 10:43:28 +0100612 disk_alloc_events(disk);
613
Wanlong Gao9f5e4862011-06-13 10:45:43 +0200614 /* Register BDI before referencing it from bdev */
Signed-off-by: Jan Kara01ea5062010-09-16 20:36:36 +0200615 bdi = &disk->queue->backing_dev_info;
616 bdi_register_dev(bdi, disk_devt(disk));
617
Tejun Heof331c022008-09-03 09:01:48 +0200618 blk_register_region(disk_devt(disk), disk->minors, NULL,
619 exact_match, exact_lock, disk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700620 register_disk(disk);
621 blk_register_queue(disk);
Peter Zijlstracf0ca9f2008-04-30 00:54:32 -0700622
Tejun Heo523e1d32011-10-19 14:31:07 +0200623 /*
624 * Take an extra ref on queue which will be put on disk_release()
625 * so that it sticks around as long as @disk is there.
626 */
Tejun Heo09ac46c2011-12-14 00:33:38 +0100627 WARN_ON_ONCE(!blk_get_queue(disk->queue));
Tejun Heo523e1d32011-10-19 14:31:07 +0200628
Tejun Heoed9e1982008-08-25 19:56:05 +0900629 retval = sysfs_create_link(&disk_to_dev(disk)->kobj, &bdi->dev->kobj,
630 "bdi");
Greg Kroah-Hartman6ffeea72008-05-22 17:21:08 -0400631 WARN_ON(retval);
Tejun Heo77ea8872010-12-08 20:57:37 +0100632
633 disk_add_events(disk);
Martin K. Petersen25520d52015-10-21 13:19:49 -0400634 blk_integrity_add(disk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700635}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700636EXPORT_SYMBOL(add_disk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700637
Tejun Heod2bf1b62010-12-08 20:57:36 +0100638void del_gendisk(struct gendisk *disk)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700639{
Tejun Heod2bf1b62010-12-08 20:57:36 +0100640 struct disk_part_iter piter;
641 struct hd_struct *part;
642
Martin K. Petersen25520d52015-10-21 13:19:49 -0400643 blk_integrity_del(disk);
Tejun Heo77ea8872010-12-08 20:57:37 +0100644 disk_del_events(disk);
645
Tejun Heod2bf1b62010-12-08 20:57:36 +0100646 /* invalidate stuff */
647 disk_part_iter_init(&piter, disk,
648 DISK_PITER_INCL_EMPTY | DISK_PITER_REVERSE);
649 while ((part = disk_part_iter_next(&piter))) {
650 invalidate_partition(disk, part->partno);
651 delete_partition(disk, part->partno);
652 }
653 disk_part_iter_exit(&piter);
654
655 invalidate_partition(disk, 0);
Tejun Heod2bf1b62010-12-08 20:57:36 +0100656 set_capacity(disk, 0);
657 disk->flags &= ~GENHD_FL_UP;
658
Tejun Heoed9e1982008-08-25 19:56:05 +0900659 sysfs_remove_link(&disk_to_dev(disk)->kobj, "bdi");
Linus Torvalds1da177e2005-04-16 15:20:36 -0700660 blk_unregister_queue(disk);
Tejun Heof331c022008-09-03 09:01:48 +0200661 blk_unregister_region(disk_devt(disk), disk->minors);
Tejun Heod2bf1b62010-12-08 20:57:36 +0100662
663 part_stat_set_all(&disk->part0, 0);
664 disk->part0.stamp = 0;
665
666 kobject_put(disk->part0.holder_dir);
667 kobject_put(disk->slave_dir);
Tejun Heod2bf1b62010-12-08 20:57:36 +0100668 if (!sysfs_deprecated)
669 sysfs_remove_link(block_depr, dev_name(disk_to_dev(disk)));
Ming Lei25e823c2013-02-22 16:34:13 -0800670 pm_runtime_set_memalloc_noio(disk_to_dev(disk), false);
Tejun Heod2bf1b62010-12-08 20:57:36 +0100671 device_del(disk_to_dev(disk));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700672}
Tejun Heod2bf1b62010-12-08 20:57:36 +0100673EXPORT_SYMBOL(del_gendisk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700674
Vishal Verma99e66082016-01-09 08:36:51 -0800675/* sysfs access to bad-blocks list. */
676static ssize_t disk_badblocks_show(struct device *dev,
677 struct device_attribute *attr,
678 char *page)
679{
680 struct gendisk *disk = dev_to_disk(dev);
681
682 if (!disk->bb)
683 return sprintf(page, "\n");
684
685 return badblocks_show(disk->bb, page, 0);
686}
687
688static ssize_t disk_badblocks_store(struct device *dev,
689 struct device_attribute *attr,
690 const char *page, size_t len)
691{
692 struct gendisk *disk = dev_to_disk(dev);
693
694 if (!disk->bb)
695 return -ENXIO;
696
697 return badblocks_store(disk->bb, page, len, 0);
698}
699
Linus Torvalds1da177e2005-04-16 15:20:36 -0700700/**
701 * get_gendisk - get partitioning information for a given device
Randy Dunlap710027a2008-08-19 20:13:11 +0200702 * @devt: device to get partitioning information for
Randy Dunlap496aa8a2008-10-16 07:46:23 +0200703 * @partno: returned partition index
Linus Torvalds1da177e2005-04-16 15:20:36 -0700704 *
705 * This function gets the structure containing partitioning
Randy Dunlap710027a2008-08-19 20:13:11 +0200706 * information for the given device @devt.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700707 */
Tejun Heocf771cb2008-09-03 09:01:09 +0200708struct gendisk *get_gendisk(dev_t devt, int *partno)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700709{
Tejun Heobcce3de2008-08-25 19:47:22 +0900710 struct gendisk *disk = NULL;
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200711
Tejun Heobcce3de2008-08-25 19:47:22 +0900712 if (MAJOR(devt) != BLOCK_EXT_MAJOR) {
713 struct kobject *kobj;
714
715 kobj = kobj_lookup(bdev_map, devt, partno);
716 if (kobj)
717 disk = dev_to_disk(kobj_to_dev(kobj));
718 } else {
719 struct hd_struct *part;
720
Dan Williams4d66e5e2015-06-10 23:47:14 -0400721 spin_lock_bh(&ext_devt_lock);
Tejun Heo870d6652008-08-25 19:47:25 +0900722 part = idr_find(&ext_devt_idr, blk_mangle_minor(MINOR(devt)));
Tejun Heobcce3de2008-08-25 19:47:22 +0900723 if (part && get_disk(part_to_disk(part))) {
724 *partno = part->partno;
725 disk = part_to_disk(part);
726 }
Dan Williams4d66e5e2015-06-10 23:47:14 -0400727 spin_unlock_bh(&ext_devt_lock);
Tejun Heobcce3de2008-08-25 19:47:22 +0900728 }
729
730 return disk;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700731}
Divyesh Shahb6ac23af2010-04-15 08:54:59 +0200732EXPORT_SYMBOL(get_gendisk);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700733
Tejun Heof331c022008-09-03 09:01:48 +0200734/**
735 * bdget_disk - do bdget() by gendisk and partition number
736 * @disk: gendisk of interest
737 * @partno: partition number
738 *
739 * Find partition @partno from @disk, do bdget() on it.
740 *
741 * CONTEXT:
742 * Don't care.
743 *
744 * RETURNS:
745 * Resulting block_device on success, NULL on failure.
746 */
Harvey Harrisonaeb3d3a2008-08-28 09:27:42 +0200747struct block_device *bdget_disk(struct gendisk *disk, int partno)
Tejun Heof331c022008-09-03 09:01:48 +0200748{
Tejun Heo548b10e2008-08-29 09:01:47 +0200749 struct hd_struct *part;
750 struct block_device *bdev = NULL;
Tejun Heof331c022008-09-03 09:01:48 +0200751
Tejun Heo548b10e2008-08-29 09:01:47 +0200752 part = disk_get_part(disk, partno);
Tejun Heo2bbedcb2008-08-29 11:41:51 +0200753 if (part)
Tejun Heo548b10e2008-08-29 09:01:47 +0200754 bdev = bdget(part_devt(part));
755 disk_put_part(part);
Tejun Heof331c022008-09-03 09:01:48 +0200756
Tejun Heo548b10e2008-08-29 09:01:47 +0200757 return bdev;
Tejun Heof331c022008-09-03 09:01:48 +0200758}
759EXPORT_SYMBOL(bdget_disk);
760
Dave Gilbertdd2a3452007-05-09 02:33:24 -0700761/*
762 * print a full list of all partitions - intended for places where the root
763 * filesystem can't be mounted and thus to give the victim some idea of what
764 * went wrong
765 */
766void __init printk_all_partitions(void)
767{
Tejun Heodef4e382008-09-03 08:57:12 +0200768 struct class_dev_iter iter;
769 struct device *dev;
770
771 class_dev_iter_init(&iter, &block_class, NULL, &disk_type);
772 while ((dev = class_dev_iter_next(&iter))) {
773 struct gendisk *disk = dev_to_disk(dev);
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200774 struct disk_part_iter piter;
775 struct hd_struct *part;
Tejun Heo1f014292008-08-25 19:47:23 +0900776 char name_buf[BDEVNAME_SIZE];
777 char devt_buf[BDEVT_SIZE];
Tejun Heodef4e382008-09-03 08:57:12 +0200778
779 /*
780 * Don't show empty devices or things that have been
Lucas De Marchi25985ed2011-03-30 22:57:33 -0300781 * suppressed
Tejun Heodef4e382008-09-03 08:57:12 +0200782 */
783 if (get_capacity(disk) == 0 ||
784 (disk->flags & GENHD_FL_SUPPRESS_PARTITION_INFO))
785 continue;
786
787 /*
788 * Note, unlike /proc/partitions, I am showing the
789 * numbers in hex - the same format as the root=
790 * option takes.
791 */
Tejun Heo074a7ac2008-08-25 19:56:14 +0900792 disk_part_iter_init(&piter, disk, DISK_PITER_INCL_PART0);
793 while ((part = disk_part_iter_next(&piter))) {
794 bool is_part0 = part == &disk->part0;
Tejun Heodef4e382008-09-03 08:57:12 +0200795
Will Drewryb5af9212010-08-31 15:47:07 -0500796 printk("%s%s %10llu %s %s", is_part0 ? "" : " ",
Tejun Heo1f014292008-08-25 19:47:23 +0900797 bdevt_str(part_devt(part), devt_buf),
Vivek Goyalc83f6bf2012-08-01 12:24:18 +0200798 (unsigned long long)part_nr_sects_read(part) >> 1
799 , disk_name(disk, part->partno, name_buf),
Stephen Warren1ad7e892012-11-08 16:12:25 -0800800 part->info ? part->info->uuid : "");
Tejun Heo074a7ac2008-08-25 19:56:14 +0900801 if (is_part0) {
802 if (disk->driverfs_dev != NULL &&
803 disk->driverfs_dev->driver != NULL)
804 printk(" driver: %s\n",
805 disk->driverfs_dev->driver->name);
806 else
807 printk(" (driver?)\n");
808 } else
809 printk("\n");
810 }
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200811 disk_part_iter_exit(&piter);
Tejun Heodef4e382008-09-03 08:57:12 +0200812 }
813 class_dev_iter_exit(&iter);
Dave Gilbertdd2a3452007-05-09 02:33:24 -0700814}
815
Linus Torvalds1da177e2005-04-16 15:20:36 -0700816#ifdef CONFIG_PROC_FS
817/* iterator */
Tejun Heodef4e382008-09-03 08:57:12 +0200818static void *disk_seqf_start(struct seq_file *seqf, loff_t *pos)
Greg Kroah-Hartman68c4d4a2008-05-22 17:21:08 -0400819{
Tejun Heodef4e382008-09-03 08:57:12 +0200820 loff_t skip = *pos;
821 struct class_dev_iter *iter;
822 struct device *dev;
Greg Kroah-Hartman68c4d4a2008-05-22 17:21:08 -0400823
Harvey Harrisonaeb3d3a2008-08-28 09:27:42 +0200824 iter = kmalloc(sizeof(*iter), GFP_KERNEL);
Tejun Heodef4e382008-09-03 08:57:12 +0200825 if (!iter)
826 return ERR_PTR(-ENOMEM);
827
828 seqf->private = iter;
829 class_dev_iter_init(iter, &block_class, NULL, &disk_type);
830 do {
831 dev = class_dev_iter_next(iter);
832 if (!dev)
833 return NULL;
834 } while (skip--);
835
836 return dev_to_disk(dev);
Greg Kroah-Hartman68c4d4a2008-05-22 17:21:08 -0400837}
838
Tejun Heodef4e382008-09-03 08:57:12 +0200839static void *disk_seqf_next(struct seq_file *seqf, void *v, loff_t *pos)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700840{
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200841 struct device *dev;
Greg Kroah-Hartman66c64af2008-05-22 17:21:08 -0400842
Tejun Heodef4e382008-09-03 08:57:12 +0200843 (*pos)++;
844 dev = class_dev_iter_next(seqf->private);
Tejun Heo2ac3cee2008-09-03 08:53:37 +0200845 if (dev)
Greg Kroah-Hartman68c4d4a2008-05-22 17:21:08 -0400846 return dev_to_disk(dev);
Tejun Heo2ac3cee2008-09-03 08:53:37 +0200847
Linus Torvalds1da177e2005-04-16 15:20:36 -0700848 return NULL;
849}
850
Tejun Heodef4e382008-09-03 08:57:12 +0200851static void disk_seqf_stop(struct seq_file *seqf, void *v)
Greg Kroah-Hartman27f30252008-05-22 17:21:08 -0400852{
Tejun Heodef4e382008-09-03 08:57:12 +0200853 struct class_dev_iter *iter = seqf->private;
Greg Kroah-Hartman27f30252008-05-22 17:21:08 -0400854
Tejun Heodef4e382008-09-03 08:57:12 +0200855 /* stop is called even after start failed :-( */
856 if (iter) {
857 class_dev_iter_exit(iter);
858 kfree(iter);
Kay Sievers5c0ef6d2008-08-16 14:30:30 +0200859 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700860}
861
Tejun Heodef4e382008-09-03 08:57:12 +0200862static void *show_partition_start(struct seq_file *seqf, loff_t *pos)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700863{
Jianpeng Ma06768062012-08-03 10:42:00 +0200864 void *p;
Tejun Heodef4e382008-09-03 08:57:12 +0200865
866 p = disk_seqf_start(seqf, pos);
Yang Zhangb9f985b2010-12-17 08:58:36 +0100867 if (!IS_ERR_OR_NULL(p) && !*pos)
Tejun Heodef4e382008-09-03 08:57:12 +0200868 seq_puts(seqf, "major minor #blocks name\n\n");
869 return p;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700870}
871
Tejun Heocf771cb2008-09-03 09:01:09 +0200872static int show_partition(struct seq_file *seqf, void *v)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700873{
874 struct gendisk *sgp = v;
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200875 struct disk_part_iter piter;
876 struct hd_struct *part;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700877 char buf[BDEVNAME_SIZE];
878
Linus Torvalds1da177e2005-04-16 15:20:36 -0700879 /* Don't show non-partitionable removeable devices or empty devices */
Tejun Heod27769e2011-08-23 20:01:04 +0200880 if (!get_capacity(sgp) || (!disk_max_parts(sgp) &&
Tejun Heof331c022008-09-03 09:01:48 +0200881 (sgp->flags & GENHD_FL_REMOVABLE)))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700882 return 0;
883 if (sgp->flags & GENHD_FL_SUPPRESS_PARTITION_INFO)
884 return 0;
885
886 /* show the full disk and all non-0 size partitions of it */
Tejun Heo074a7ac2008-08-25 19:56:14 +0900887 disk_part_iter_init(&piter, sgp, DISK_PITER_INCL_PART0);
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200888 while ((part = disk_part_iter_next(&piter)))
Tejun Heo1f014292008-08-25 19:47:23 +0900889 seq_printf(seqf, "%4d %7d %10llu %s\n",
Tejun Heof331c022008-09-03 09:01:48 +0200890 MAJOR(part_devt(part)), MINOR(part_devt(part)),
Vivek Goyalc83f6bf2012-08-01 12:24:18 +0200891 (unsigned long long)part_nr_sects_read(part) >> 1,
Tejun Heof331c022008-09-03 09:01:48 +0200892 disk_name(sgp, part->partno, buf));
Tejun Heoe71bf0d2008-09-03 09:03:02 +0200893 disk_part_iter_exit(&piter);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700894
895 return 0;
896}
897
Alexey Dobriyanf5009752008-10-04 23:53:21 +0400898static const struct seq_operations partitions_op = {
Tejun Heodef4e382008-09-03 08:57:12 +0200899 .start = show_partition_start,
900 .next = disk_seqf_next,
901 .stop = disk_seqf_stop,
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200902 .show = show_partition
Linus Torvalds1da177e2005-04-16 15:20:36 -0700903};
Alexey Dobriyanf5009752008-10-04 23:53:21 +0400904
905static int partitions_open(struct inode *inode, struct file *file)
906{
907 return seq_open(file, &partitions_op);
908}
909
910static const struct file_operations proc_partitions_operations = {
911 .open = partitions_open,
912 .read = seq_read,
913 .llseek = seq_lseek,
914 .release = seq_release,
915};
Linus Torvalds1da177e2005-04-16 15:20:36 -0700916#endif
917
918
Tejun Heocf771cb2008-09-03 09:01:09 +0200919static struct kobject *base_probe(dev_t devt, int *partno, void *data)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700920{
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200921 if (request_module("block-major-%d-%d", MAJOR(devt), MINOR(devt)) > 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700922 /* Make old-style 2.4 aliases work */
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200923 request_module("block-major-%d", MAJOR(devt));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700924 return NULL;
925}
926
927static int __init genhd_device_init(void)
928{
Dan Williamse105b8b2008-04-21 10:51:07 -0700929 int error;
930
931 block_class.dev_kobj = sysfs_dev_block_kobj;
932 error = class_register(&block_class);
Roland McGrathee27a552008-03-11 17:13:15 -0700933 if (unlikely(error))
934 return error;
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200935 bdev_map = kobj_map_init(base_probe, &block_class_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700936 blk_dev_init();
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200937
Zhang, Yanmin561ec682008-11-14 08:26:30 +0100938 register_blkdev(BLOCK_EXT_MAJOR, "blkext");
939
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200940 /* create top-level block dir */
Andi Kleene52eec12010-09-08 16:54:17 +0200941 if (!sysfs_deprecated)
942 block_depr = kobject_create_and_add("block", NULL);
Greg Kroah-Hartman830d3cf2007-11-06 10:36:58 -0800943 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700944}
945
946subsys_initcall(genhd_device_init);
947
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200948static ssize_t disk_range_show(struct device *dev,
949 struct device_attribute *attr, char *buf)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700950{
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200951 struct gendisk *disk = dev_to_disk(dev);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700952
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200953 return sprintf(buf, "%d\n", disk->minors);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700954}
955
Tejun Heo1f014292008-08-25 19:47:23 +0900956static ssize_t disk_ext_range_show(struct device *dev,
957 struct device_attribute *attr, char *buf)
958{
959 struct gendisk *disk = dev_to_disk(dev);
960
Tejun Heob5d0b9d2008-09-03 09:06:42 +0200961 return sprintf(buf, "%d\n", disk_max_parts(disk));
Tejun Heo1f014292008-08-25 19:47:23 +0900962}
963
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200964static ssize_t disk_removable_show(struct device *dev,
965 struct device_attribute *attr, char *buf)
Kay Sieversa7fd6702005-10-01 14:49:43 +0200966{
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200967 struct gendisk *disk = dev_to_disk(dev);
Kay Sieversa7fd6702005-10-01 14:49:43 +0200968
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200969 return sprintf(buf, "%d\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700970 (disk->flags & GENHD_FL_REMOVABLE ? 1 : 0));
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200971}
Linus Torvalds1da177e2005-04-16 15:20:36 -0700972
Kay Sievers1c9ce522008-06-13 09:41:00 +0200973static ssize_t disk_ro_show(struct device *dev,
974 struct device_attribute *attr, char *buf)
975{
976 struct gendisk *disk = dev_to_disk(dev);
977
Tejun Heob7db9952008-08-25 19:56:10 +0900978 return sprintf(buf, "%d\n", get_disk_ro(disk) ? 1 : 0);
Kay Sievers1c9ce522008-06-13 09:41:00 +0200979}
980
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200981static ssize_t disk_capability_show(struct device *dev,
982 struct device_attribute *attr, char *buf)
Kristen Carlson Accardi86ce18d2007-05-23 13:57:38 -0700983{
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200984 struct gendisk *disk = dev_to_disk(dev);
985
986 return sprintf(buf, "%x\n", disk->flags);
Kristen Carlson Accardi86ce18d2007-05-23 13:57:38 -0700987}
Kay Sieversedfaa7c2007-05-21 22:08:01 +0200988
Martin K. Petersenc72758f2009-05-22 17:17:53 -0400989static ssize_t disk_alignment_offset_show(struct device *dev,
990 struct device_attribute *attr,
991 char *buf)
992{
993 struct gendisk *disk = dev_to_disk(dev);
994
995 return sprintf(buf, "%d\n", queue_alignment_offset(disk->queue));
996}
997
Martin K. Petersen86b37282009-11-10 11:50:21 +0100998static ssize_t disk_discard_alignment_show(struct device *dev,
999 struct device_attribute *attr,
1000 char *buf)
1001{
1002 struct gendisk *disk = dev_to_disk(dev);
1003
Martin K. Petersendd3d1452010-01-11 03:21:48 -05001004 return sprintf(buf, "%d\n", queue_discard_alignment(disk->queue));
Martin K. Petersen86b37282009-11-10 11:50:21 +01001005}
1006
Kay Sieversedfaa7c2007-05-21 22:08:01 +02001007static DEVICE_ATTR(range, S_IRUGO, disk_range_show, NULL);
Tejun Heo1f014292008-08-25 19:47:23 +09001008static DEVICE_ATTR(ext_range, S_IRUGO, disk_ext_range_show, NULL);
Kay Sieversedfaa7c2007-05-21 22:08:01 +02001009static DEVICE_ATTR(removable, S_IRUGO, disk_removable_show, NULL);
Kay Sievers1c9ce522008-06-13 09:41:00 +02001010static DEVICE_ATTR(ro, S_IRUGO, disk_ro_show, NULL);
Tejun Heoe5610522008-08-25 19:56:09 +09001011static DEVICE_ATTR(size, S_IRUGO, part_size_show, NULL);
Martin K. Petersenc72758f2009-05-22 17:17:53 -04001012static DEVICE_ATTR(alignment_offset, S_IRUGO, disk_alignment_offset_show, NULL);
Martin K. Petersen86b37282009-11-10 11:50:21 +01001013static DEVICE_ATTR(discard_alignment, S_IRUGO, disk_discard_alignment_show,
1014 NULL);
Kay Sieversedfaa7c2007-05-21 22:08:01 +02001015static DEVICE_ATTR(capability, S_IRUGO, disk_capability_show, NULL);
Tejun Heo074a7ac2008-08-25 19:56:14 +09001016static DEVICE_ATTR(stat, S_IRUGO, part_stat_show, NULL);
Nikanth Karthikesan316d3152009-10-06 20:16:55 +02001017static DEVICE_ATTR(inflight, S_IRUGO, part_inflight_show, NULL);
Vishal Verma99e66082016-01-09 08:36:51 -08001018static DEVICE_ATTR(badblocks, S_IRUGO | S_IWUSR, disk_badblocks_show,
1019 disk_badblocks_store);
Akinobu Mitac17bb492006-12-08 02:39:46 -08001020#ifdef CONFIG_FAIL_MAKE_REQUEST
Kay Sieversedfaa7c2007-05-21 22:08:01 +02001021static struct device_attribute dev_attr_fail =
Tejun Heoeddb2e22008-08-25 19:56:13 +09001022 __ATTR(make-it-fail, S_IRUGO|S_IWUSR, part_fail_show, part_fail_store);
Akinobu Mitac17bb492006-12-08 02:39:46 -08001023#endif
Jens Axboe581d4e22008-09-14 05:56:33 -07001024#ifdef CONFIG_FAIL_IO_TIMEOUT
1025static struct device_attribute dev_attr_fail_timeout =
1026 __ATTR(io-timeout-fail, S_IRUGO|S_IWUSR, part_timeout_show,
1027 part_timeout_store);
1028#endif
Kay Sieversedfaa7c2007-05-21 22:08:01 +02001029
1030static struct attribute *disk_attrs[] = {
1031 &dev_attr_range.attr,
Tejun Heo1f014292008-08-25 19:47:23 +09001032 &dev_attr_ext_range.attr,
Kay Sieversedfaa7c2007-05-21 22:08:01 +02001033 &dev_attr_removable.attr,
Kay Sievers1c9ce522008-06-13 09:41:00 +02001034 &dev_attr_ro.attr,
Kay Sieversedfaa7c2007-05-21 22:08:01 +02001035 &dev_attr_size.attr,
Martin K. Petersenc72758f2009-05-22 17:17:53 -04001036 &dev_attr_alignment_offset.attr,
Martin K. Petersen86b37282009-11-10 11:50:21 +01001037 &dev_attr_discard_alignment.attr,
Kay Sieversedfaa7c2007-05-21 22:08:01 +02001038 &dev_attr_capability.attr,
1039 &dev_attr_stat.attr,
Nikanth Karthikesan316d3152009-10-06 20:16:55 +02001040 &dev_attr_inflight.attr,
Vishal Verma99e66082016-01-09 08:36:51 -08001041 &dev_attr_badblocks.attr,
Kay Sieversedfaa7c2007-05-21 22:08:01 +02001042#ifdef CONFIG_FAIL_MAKE_REQUEST
1043 &dev_attr_fail.attr,
1044#endif
Jens Axboe581d4e22008-09-14 05:56:33 -07001045#ifdef CONFIG_FAIL_IO_TIMEOUT
1046 &dev_attr_fail_timeout.attr,
1047#endif
Kay Sieversedfaa7c2007-05-21 22:08:01 +02001048 NULL
Linus Torvalds1da177e2005-04-16 15:20:36 -07001049};
1050
Kay Sieversedfaa7c2007-05-21 22:08:01 +02001051static struct attribute_group disk_attr_group = {
1052 .attrs = disk_attrs,
1053};
1054
David Brownella4dbd672009-06-24 10:06:31 -07001055static const struct attribute_group *disk_attr_groups[] = {
Kay Sieversedfaa7c2007-05-21 22:08:01 +02001056 &disk_attr_group,
1057 NULL
1058};
1059
Tejun Heo540eed52008-08-25 19:56:15 +09001060/**
1061 * disk_replace_part_tbl - replace disk->part_tbl in RCU-safe way
1062 * @disk: disk to replace part_tbl for
1063 * @new_ptbl: new part_tbl to install
1064 *
1065 * Replace disk->part_tbl with @new_ptbl in RCU-safe way. The
1066 * original ptbl is freed using RCU callback.
1067 *
1068 * LOCKING:
1069 * Matching bd_mutx locked.
1070 */
1071static void disk_replace_part_tbl(struct gendisk *disk,
1072 struct disk_part_tbl *new_ptbl)
1073{
1074 struct disk_part_tbl *old_ptbl = disk->part_tbl;
1075
1076 rcu_assign_pointer(disk->part_tbl, new_ptbl);
Jens Axboea6f23652008-10-24 12:52:42 +02001077
1078 if (old_ptbl) {
1079 rcu_assign_pointer(old_ptbl->last_lookup, NULL);
Lai Jiangshan57bdfbf2011-03-18 11:42:58 +08001080 kfree_rcu(old_ptbl, rcu_head);
Jens Axboea6f23652008-10-24 12:52:42 +02001081 }
Tejun Heo540eed52008-08-25 19:56:15 +09001082}
1083
1084/**
1085 * disk_expand_part_tbl - expand disk->part_tbl
1086 * @disk: disk to expand part_tbl for
1087 * @partno: expand such that this partno can fit in
1088 *
1089 * Expand disk->part_tbl such that @partno can fit in. disk->part_tbl
1090 * uses RCU to allow unlocked dereferencing for stats and other stuff.
1091 *
1092 * LOCKING:
1093 * Matching bd_mutex locked, might sleep.
1094 *
1095 * RETURNS:
1096 * 0 on success, -errno on failure.
1097 */
1098int disk_expand_part_tbl(struct gendisk *disk, int partno)
1099{
1100 struct disk_part_tbl *old_ptbl = disk->part_tbl;
1101 struct disk_part_tbl *new_ptbl;
1102 int len = old_ptbl ? old_ptbl->len : 0;
Jens Axboe5fabcb42014-11-19 13:06:22 -07001103 int i, target;
Tejun Heo540eed52008-08-25 19:56:15 +09001104 size_t size;
Jens Axboe5fabcb42014-11-19 13:06:22 -07001105
1106 /*
1107 * check for int overflow, since we can get here from blkpg_ioctl()
1108 * with a user passed 'partno'.
1109 */
1110 target = partno + 1;
1111 if (target < 0)
1112 return -EINVAL;
Tejun Heo540eed52008-08-25 19:56:15 +09001113
1114 /* disk_max_parts() is zero during initialization, ignore if so */
1115 if (disk_max_parts(disk) && target > disk_max_parts(disk))
1116 return -EINVAL;
1117
1118 if (target <= len)
1119 return 0;
1120
1121 size = sizeof(*new_ptbl) + target * sizeof(new_ptbl->part[0]);
1122 new_ptbl = kzalloc_node(size, GFP_KERNEL, disk->node_id);
1123 if (!new_ptbl)
1124 return -ENOMEM;
1125
Tejun Heo540eed52008-08-25 19:56:15 +09001126 new_ptbl->len = target;
1127
1128 for (i = 0; i < len; i++)
1129 rcu_assign_pointer(new_ptbl->part[i], old_ptbl->part[i]);
1130
1131 disk_replace_part_tbl(disk, new_ptbl);
1132 return 0;
1133}
1134
Kay Sieversedfaa7c2007-05-21 22:08:01 +02001135static void disk_release(struct device *dev)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001136{
Kay Sieversedfaa7c2007-05-21 22:08:01 +02001137 struct gendisk *disk = dev_to_disk(dev);
1138
Keith Busch2da78092014-08-26 09:05:36 -06001139 blk_free_devt(dev->devt);
Tejun Heo77ea8872010-12-08 20:57:37 +01001140 disk_release_events(disk);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001141 kfree(disk->random);
Tejun Heo540eed52008-08-25 19:56:15 +09001142 disk_replace_part_tbl(disk, NULL);
Ming Leib54e5ed2015-07-16 11:16:44 +08001143 hd_free_part(&disk->part0);
Tejun Heo523e1d32011-10-19 14:31:07 +02001144 if (disk->queue)
1145 blk_put_queue(disk->queue);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001146 kfree(disk);
1147}
Kay Sieversedfaa7c2007-05-21 22:08:01 +02001148struct class block_class = {
1149 .name = "block",
Linus Torvalds1da177e2005-04-16 15:20:36 -07001150};
1151
Kay Sievers3c2670e2013-04-06 09:56:00 -07001152static char *block_devnode(struct device *dev, umode_t *mode,
Greg Kroah-Hartman4e4098a2013-04-11 11:43:29 -07001153 kuid_t *uid, kgid_t *gid)
Kay Sieversb03f38b2009-04-30 15:23:42 +02001154{
1155 struct gendisk *disk = dev_to_disk(dev);
1156
Kay Sieverse454cea2009-09-18 23:01:12 +02001157 if (disk->devnode)
1158 return disk->devnode(disk, mode);
Kay Sieversb03f38b2009-04-30 15:23:42 +02001159 return NULL;
1160}
1161
Adrian Bunk1826ead2008-03-04 11:23:46 +01001162static struct device_type disk_type = {
Kay Sieversedfaa7c2007-05-21 22:08:01 +02001163 .name = "disk",
1164 .groups = disk_attr_groups,
1165 .release = disk_release,
Kay Sieverse454cea2009-09-18 23:01:12 +02001166 .devnode = block_devnode,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001167};
1168
Randy Dunlapa6e2ba82008-05-23 09:44:11 -07001169#ifdef CONFIG_PROC_FS
Tejun Heocf771cb2008-09-03 09:01:09 +02001170/*
1171 * aggregate disk stat collector. Uses the same stats that the sysfs
1172 * entries do, above, but makes them available through one seq_file.
1173 *
1174 * The output looks suspiciously like /proc/partitions with a bunch of
1175 * extra fields.
1176 */
1177static int diskstats_show(struct seq_file *seqf, void *v)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001178{
1179 struct gendisk *gp = v;
Tejun Heoe71bf0d2008-09-03 09:03:02 +02001180 struct disk_part_iter piter;
1181 struct hd_struct *hd;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001182 char buf[BDEVNAME_SIZE];
Tejun Heoc9959052008-08-25 19:47:21 +09001183 int cpu;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001184
1185 /*
Tejun Heoed9e1982008-08-25 19:56:05 +09001186 if (&disk_to_dev(gp)->kobj.entry == block_class.devices.next)
Tejun Heocf771cb2008-09-03 09:01:09 +02001187 seq_puts(seqf, "major minor name"
Linus Torvalds1da177e2005-04-16 15:20:36 -07001188 " rio rmerge rsect ruse wio wmerge "
1189 "wsect wuse running use aveq"
1190 "\n\n");
1191 */
Wanlong Gao9f5e4862011-06-13 10:45:43 +02001192
Tejun Heo71982a42009-04-17 08:34:48 +02001193 disk_part_iter_init(&piter, gp, DISK_PITER_INCL_EMPTY_PART0);
Tejun Heoe71bf0d2008-09-03 09:03:02 +02001194 while ((hd = disk_part_iter_next(&piter))) {
Tejun Heo074a7ac2008-08-25 19:56:14 +09001195 cpu = part_stat_lock();
Tejun Heoc9959052008-08-25 19:47:21 +09001196 part_round_stats(cpu, hd);
Tejun Heo074a7ac2008-08-25 19:56:14 +09001197 part_stat_unlock();
Herbert Poetzlf95fe9c2011-08-02 12:43:50 +02001198 seq_printf(seqf, "%4d %7d %s %lu %lu %lu "
1199 "%u %lu %lu %lu %u %u %u %u\n",
Tejun Heof331c022008-09-03 09:01:48 +02001200 MAJOR(part_devt(hd)), MINOR(part_devt(hd)),
1201 disk_name(gp, hd->partno, buf),
Liu Yuan53f22952011-03-02 11:00:15 -05001202 part_stat_read(hd, ios[READ]),
1203 part_stat_read(hd, merges[READ]),
Herbert Poetzlf95fe9c2011-08-02 12:43:50 +02001204 part_stat_read(hd, sectors[READ]),
Liu Yuan53f22952011-03-02 11:00:15 -05001205 jiffies_to_msecs(part_stat_read(hd, ticks[READ])),
1206 part_stat_read(hd, ios[WRITE]),
1207 part_stat_read(hd, merges[WRITE]),
Herbert Poetzlf95fe9c2011-08-02 12:43:50 +02001208 part_stat_read(hd, sectors[WRITE]),
Liu Yuan53f22952011-03-02 11:00:15 -05001209 jiffies_to_msecs(part_stat_read(hd, ticks[WRITE])),
Nikanth Karthikesan316d3152009-10-06 20:16:55 +02001210 part_in_flight(hd),
Jerome Marchand28f39d52008-02-08 11:04:56 +01001211 jiffies_to_msecs(part_stat_read(hd, io_ticks)),
1212 jiffies_to_msecs(part_stat_read(hd, time_in_queue))
1213 );
Linus Torvalds1da177e2005-04-16 15:20:36 -07001214 }
Tejun Heoe71bf0d2008-09-03 09:03:02 +02001215 disk_part_iter_exit(&piter);
Wanlong Gao9f5e4862011-06-13 10:45:43 +02001216
Linus Torvalds1da177e2005-04-16 15:20:36 -07001217 return 0;
1218}
1219
Alexey Dobriyan31d85ab2008-10-06 12:55:38 +04001220static const struct seq_operations diskstats_op = {
Tejun Heodef4e382008-09-03 08:57:12 +02001221 .start = disk_seqf_start,
1222 .next = disk_seqf_next,
1223 .stop = disk_seqf_stop,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001224 .show = diskstats_show
1225};
Alexey Dobriyanf5009752008-10-04 23:53:21 +04001226
Alexey Dobriyan31d85ab2008-10-06 12:55:38 +04001227static int diskstats_open(struct inode *inode, struct file *file)
1228{
1229 return seq_open(file, &diskstats_op);
1230}
1231
1232static const struct file_operations proc_diskstats_operations = {
1233 .open = diskstats_open,
1234 .read = seq_read,
1235 .llseek = seq_lseek,
1236 .release = seq_release,
1237};
1238
Alexey Dobriyanf5009752008-10-04 23:53:21 +04001239static int __init proc_genhd_init(void)
1240{
Alexey Dobriyan31d85ab2008-10-06 12:55:38 +04001241 proc_create("diskstats", 0, NULL, &proc_diskstats_operations);
Alexey Dobriyanf5009752008-10-04 23:53:21 +04001242 proc_create("partitions", 0, NULL, &proc_partitions_operations);
1243 return 0;
1244}
1245module_init(proc_genhd_init);
Randy Dunlapa6e2ba82008-05-23 09:44:11 -07001246#endif /* CONFIG_PROC_FS */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001247
Tejun Heocf771cb2008-09-03 09:01:09 +02001248dev_t blk_lookup_devt(const char *name, int partno)
Kay Sieversedfaa7c2007-05-21 22:08:01 +02001249{
Kay Sieversedfaa7c2007-05-21 22:08:01 +02001250 dev_t devt = MKDEV(0, 0);
Tejun Heodef4e382008-09-03 08:57:12 +02001251 struct class_dev_iter iter;
1252 struct device *dev;
Kay Sieversedfaa7c2007-05-21 22:08:01 +02001253
Tejun Heodef4e382008-09-03 08:57:12 +02001254 class_dev_iter_init(&iter, &block_class, NULL, &disk_type);
1255 while ((dev = class_dev_iter_next(&iter))) {
1256 struct gendisk *disk = dev_to_disk(dev);
Tejun Heo548b10e2008-08-29 09:01:47 +02001257 struct hd_struct *part;
Tejun Heodef4e382008-09-03 08:57:12 +02001258
Kay Sievers3ada8b72009-01-06 10:44:43 -08001259 if (strcmp(dev_name(dev), name))
Tejun Heof331c022008-09-03 09:01:48 +02001260 continue;
Tejun Heof331c022008-09-03 09:01:48 +02001261
Neil Brown41b8c852009-02-18 10:33:59 +01001262 if (partno < disk->minors) {
1263 /* We need to return the right devno, even
1264 * if the partition doesn't exist yet.
1265 */
1266 devt = MKDEV(MAJOR(dev->devt),
1267 MINOR(dev->devt) + partno);
1268 break;
1269 }
Tejun Heo548b10e2008-08-29 09:01:47 +02001270 part = disk_get_part(disk, partno);
Tejun Heo2bbedcb2008-08-29 11:41:51 +02001271 if (part) {
Tejun Heof331c022008-09-03 09:01:48 +02001272 devt = part_devt(part);
Tejun Heoe71bf0d2008-09-03 09:03:02 +02001273 disk_put_part(part);
Tejun Heo548b10e2008-08-29 09:01:47 +02001274 break;
Tejun Heodef4e382008-09-03 08:57:12 +02001275 }
Tejun Heo548b10e2008-08-29 09:01:47 +02001276 disk_put_part(part);
Kay Sievers5c0ef6d2008-08-16 14:30:30 +02001277 }
Tejun Heodef4e382008-09-03 08:57:12 +02001278 class_dev_iter_exit(&iter);
Kay Sieversedfaa7c2007-05-21 22:08:01 +02001279 return devt;
1280}
Kay Sieversedfaa7c2007-05-21 22:08:01 +02001281EXPORT_SYMBOL(blk_lookup_devt);
1282
Linus Torvalds1da177e2005-04-16 15:20:36 -07001283struct gendisk *alloc_disk(int minors)
1284{
Ezequiel Garciac304a512012-11-10 10:39:44 +01001285 return alloc_disk_node(minors, NUMA_NO_NODE);
Christoph Lameter19460892005-06-23 00:08:19 -07001286}
Tejun Heo689d6fa2008-08-25 19:56:16 +09001287EXPORT_SYMBOL(alloc_disk);
Christoph Lameter19460892005-06-23 00:08:19 -07001288
1289struct gendisk *alloc_disk_node(int minors, int node_id)
1290{
1291 struct gendisk *disk;
1292
Joe Perchesc1b511e2013-08-29 15:21:42 -07001293 disk = kzalloc_node(sizeof(struct gendisk), GFP_KERNEL, node_id);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001294 if (disk) {
Tejun Heo074a7ac2008-08-25 19:56:14 +09001295 if (!init_part_stats(&disk->part0)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001296 kfree(disk);
1297 return NULL;
1298 }
Cheng Renquanbf91db12008-11-20 08:37:37 +01001299 disk->node_id = node_id;
Tejun Heo540eed52008-08-25 19:56:15 +09001300 if (disk_expand_part_tbl(disk, 0)) {
1301 free_part_stats(&disk->part0);
Tejun Heob5d0b9d2008-09-03 09:06:42 +02001302 kfree(disk);
1303 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001304 }
Tejun Heo540eed52008-08-25 19:56:15 +09001305 disk->part_tbl->part[0] = &disk->part0;
Jens Axboe6c23a962011-01-07 08:43:37 +01001306
Vivek Goyalc83f6bf2012-08-01 12:24:18 +02001307 /*
1308 * set_capacity() and get_capacity() currently don't use
1309 * seqcounter to read/update the part0->nr_sects. Still init
1310 * the counter as we can read the sectors in IO submission
1311 * patch using seqence counters.
1312 *
1313 * TODO: Ideally set_capacity() and get_capacity() should be
1314 * converted to make use of bd_mutex and sequence counters.
1315 */
1316 seqcount_init(&disk->part0.nr_sects_seq);
Ming Lei6c710132015-07-16 11:16:45 +08001317 if (hd_ref_init(&disk->part0)) {
1318 hd_free_part(&disk->part0);
1319 kfree(disk);
1320 return NULL;
1321 }
Tejun Heob5d0b9d2008-09-03 09:06:42 +02001322
Linus Torvalds1da177e2005-04-16 15:20:36 -07001323 disk->minors = minors;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001324 rand_initialize_disk(disk);
Tejun Heoed9e1982008-08-25 19:56:05 +09001325 disk_to_dev(disk)->class = &block_class;
1326 disk_to_dev(disk)->type = &disk_type;
1327 device_initialize(disk_to_dev(disk));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001328 }
1329 return disk;
1330}
Christoph Lameter19460892005-06-23 00:08:19 -07001331EXPORT_SYMBOL(alloc_disk_node);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001332
1333struct kobject *get_disk(struct gendisk *disk)
1334{
1335 struct module *owner;
1336 struct kobject *kobj;
1337
1338 if (!disk->fops)
1339 return NULL;
1340 owner = disk->fops->owner;
1341 if (owner && !try_module_get(owner))
1342 return NULL;
Tejun Heoed9e1982008-08-25 19:56:05 +09001343 kobj = kobject_get(&disk_to_dev(disk)->kobj);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001344 if (kobj == NULL) {
1345 module_put(owner);
1346 return NULL;
1347 }
1348 return kobj;
1349
1350}
1351
1352EXPORT_SYMBOL(get_disk);
1353
1354void put_disk(struct gendisk *disk)
1355{
1356 if (disk)
Tejun Heoed9e1982008-08-25 19:56:05 +09001357 kobject_put(&disk_to_dev(disk)->kobj);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001358}
1359
1360EXPORT_SYMBOL(put_disk);
1361
Hannes Reineckee3264a42009-07-28 09:13:13 +02001362static void set_disk_ro_uevent(struct gendisk *gd, int ro)
1363{
1364 char event[] = "DISK_RO=1";
1365 char *envp[] = { event, NULL };
1366
1367 if (!ro)
1368 event[8] = '0';
1369 kobject_uevent_env(&disk_to_dev(gd)->kobj, KOBJ_CHANGE, envp);
1370}
1371
Linus Torvalds1da177e2005-04-16 15:20:36 -07001372void set_device_ro(struct block_device *bdev, int flag)
1373{
Tejun Heob7db9952008-08-25 19:56:10 +09001374 bdev->bd_part->policy = flag;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001375}
1376
1377EXPORT_SYMBOL(set_device_ro);
1378
1379void set_disk_ro(struct gendisk *disk, int flag)
1380{
Tejun Heoe71bf0d2008-09-03 09:03:02 +02001381 struct disk_part_iter piter;
1382 struct hd_struct *part;
1383
Hannes Reineckee3264a42009-07-28 09:13:13 +02001384 if (disk->part0.policy != flag) {
1385 set_disk_ro_uevent(disk, flag);
1386 disk->part0.policy = flag;
1387 }
1388
1389 disk_part_iter_init(&piter, disk, DISK_PITER_INCL_EMPTY);
Tejun Heoe71bf0d2008-09-03 09:03:02 +02001390 while ((part = disk_part_iter_next(&piter)))
1391 part->policy = flag;
1392 disk_part_iter_exit(&piter);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001393}
1394
1395EXPORT_SYMBOL(set_disk_ro);
1396
1397int bdev_read_only(struct block_device *bdev)
1398{
1399 if (!bdev)
1400 return 0;
Tejun Heob7db9952008-08-25 19:56:10 +09001401 return bdev->bd_part->policy;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001402}
1403
1404EXPORT_SYMBOL(bdev_read_only);
1405
Tejun Heocf771cb2008-09-03 09:01:09 +02001406int invalidate_partition(struct gendisk *disk, int partno)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001407{
1408 int res = 0;
Tejun Heocf771cb2008-09-03 09:01:09 +02001409 struct block_device *bdev = bdget_disk(disk, partno);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001410 if (bdev) {
Christoph Hellwig2ef41632005-05-05 16:15:59 -07001411 fsync_bdev(bdev);
NeilBrown93b270f2011-02-24 17:25:47 +11001412 res = __invalidate_device(bdev, true);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001413 bdput(bdev);
1414 }
1415 return res;
1416}
1417
1418EXPORT_SYMBOL(invalidate_partition);
Tejun Heo77ea8872010-12-08 20:57:37 +01001419
1420/*
1421 * Disk events - monitor disk events like media change and eject request.
1422 */
1423struct disk_events {
1424 struct list_head node; /* all disk_event's */
1425 struct gendisk *disk; /* the associated disk */
1426 spinlock_t lock;
1427
Tejun Heofdd514e2011-06-09 20:43:59 +02001428 struct mutex block_mutex; /* protects blocking */
Tejun Heo77ea8872010-12-08 20:57:37 +01001429 int block; /* event blocking depth */
1430 unsigned int pending; /* events already sent out */
1431 unsigned int clearing; /* events being cleared */
1432
1433 long poll_msecs; /* interval, -1 for default */
1434 struct delayed_work dwork;
1435};
1436
1437static const char *disk_events_strs[] = {
1438 [ilog2(DISK_EVENT_MEDIA_CHANGE)] = "media_change",
1439 [ilog2(DISK_EVENT_EJECT_REQUEST)] = "eject_request",
1440};
1441
1442static char *disk_uevents[] = {
1443 [ilog2(DISK_EVENT_MEDIA_CHANGE)] = "DISK_MEDIA_CHANGE=1",
1444 [ilog2(DISK_EVENT_EJECT_REQUEST)] = "DISK_EJECT_REQUEST=1",
1445};
1446
1447/* list of all disk_events */
1448static DEFINE_MUTEX(disk_events_mutex);
1449static LIST_HEAD(disk_events);
1450
1451/* disable in-kernel polling by default */
Wei Tang1fe8f342015-11-24 09:58:46 +08001452static unsigned long disk_events_dfl_poll_msecs;
Tejun Heo77ea8872010-12-08 20:57:37 +01001453
1454static unsigned long disk_events_poll_jiffies(struct gendisk *disk)
1455{
1456 struct disk_events *ev = disk->ev;
1457 long intv_msecs = 0;
1458
1459 /*
1460 * If device-specific poll interval is set, always use it. If
1461 * the default is being used, poll iff there are events which
1462 * can't be monitored asynchronously.
1463 */
1464 if (ev->poll_msecs >= 0)
1465 intv_msecs = ev->poll_msecs;
1466 else if (disk->events & ~disk->async_events)
1467 intv_msecs = disk_events_dfl_poll_msecs;
1468
1469 return msecs_to_jiffies(intv_msecs);
1470}
1471
Tejun Heoc3af54a2011-06-09 20:43:55 +02001472/**
1473 * disk_block_events - block and flush disk event checking
1474 * @disk: disk to block events for
1475 *
1476 * On return from this function, it is guaranteed that event checking
1477 * isn't in progress and won't happen until unblocked by
1478 * disk_unblock_events(). Events blocking is counted and the actual
1479 * unblocking happens after the matching number of unblocks are done.
1480 *
1481 * Note that this intentionally does not block event checking from
1482 * disk_clear_events().
1483 *
1484 * CONTEXT:
1485 * Might sleep.
1486 */
1487void disk_block_events(struct gendisk *disk)
Tejun Heo77ea8872010-12-08 20:57:37 +01001488{
1489 struct disk_events *ev = disk->ev;
1490 unsigned long flags;
1491 bool cancel;
1492
Tejun Heoc3af54a2011-06-09 20:43:55 +02001493 if (!ev)
1494 return;
1495
Tejun Heofdd514e2011-06-09 20:43:59 +02001496 /*
1497 * Outer mutex ensures that the first blocker completes canceling
1498 * the event work before further blockers are allowed to finish.
1499 */
1500 mutex_lock(&ev->block_mutex);
1501
Tejun Heo77ea8872010-12-08 20:57:37 +01001502 spin_lock_irqsave(&ev->lock, flags);
1503 cancel = !ev->block++;
1504 spin_unlock_irqrestore(&ev->lock, flags);
1505
Tejun Heoc3af54a2011-06-09 20:43:55 +02001506 if (cancel)
1507 cancel_delayed_work_sync(&disk->ev->dwork);
Tejun Heofdd514e2011-06-09 20:43:59 +02001508
1509 mutex_unlock(&ev->block_mutex);
Tejun Heo77ea8872010-12-08 20:57:37 +01001510}
1511
1512static void __disk_unblock_events(struct gendisk *disk, bool check_now)
1513{
1514 struct disk_events *ev = disk->ev;
1515 unsigned long intv;
1516 unsigned long flags;
1517
1518 spin_lock_irqsave(&ev->lock, flags);
1519
1520 if (WARN_ON_ONCE(ev->block <= 0))
1521 goto out_unlock;
1522
1523 if (--ev->block)
1524 goto out_unlock;
1525
1526 /*
1527 * Not exactly a latency critical operation, set poll timer
1528 * slack to 25% and kick event check.
1529 */
1530 intv = disk_events_poll_jiffies(disk);
1531 set_timer_slack(&ev->dwork.timer, intv / 4);
1532 if (check_now)
Viresh Kumar695588f2013-04-24 17:12:56 +05301533 queue_delayed_work(system_freezable_power_efficient_wq,
1534 &ev->dwork, 0);
Tejun Heo77ea8872010-12-08 20:57:37 +01001535 else if (intv)
Viresh Kumar695588f2013-04-24 17:12:56 +05301536 queue_delayed_work(system_freezable_power_efficient_wq,
1537 &ev->dwork, intv);
Tejun Heo77ea8872010-12-08 20:57:37 +01001538out_unlock:
1539 spin_unlock_irqrestore(&ev->lock, flags);
1540}
1541
1542/**
Tejun Heo77ea8872010-12-08 20:57:37 +01001543 * disk_unblock_events - unblock disk event checking
1544 * @disk: disk to unblock events for
1545 *
1546 * Undo disk_block_events(). When the block count reaches zero, it
1547 * starts events polling if configured.
1548 *
1549 * CONTEXT:
1550 * Don't care. Safe to call from irq context.
1551 */
1552void disk_unblock_events(struct gendisk *disk)
1553{
1554 if (disk->ev)
Tejun Heofacc31d2011-03-09 19:54:27 +01001555 __disk_unblock_events(disk, false);
Tejun Heo77ea8872010-12-08 20:57:37 +01001556}
1557
1558/**
Tejun Heo85ef06d2011-07-01 16:17:47 +02001559 * disk_flush_events - schedule immediate event checking and flushing
1560 * @disk: disk to check and flush events for
1561 * @mask: events to flush
Tejun Heo77ea8872010-12-08 20:57:37 +01001562 *
Tejun Heo85ef06d2011-07-01 16:17:47 +02001563 * Schedule immediate event checking on @disk if not blocked. Events in
1564 * @mask are scheduled to be cleared from the driver. Note that this
1565 * doesn't clear the events from @disk->ev.
Tejun Heo77ea8872010-12-08 20:57:37 +01001566 *
1567 * CONTEXT:
Tejun Heo85ef06d2011-07-01 16:17:47 +02001568 * If @mask is non-zero must be called with bdev->bd_mutex held.
Tejun Heo77ea8872010-12-08 20:57:37 +01001569 */
Tejun Heo85ef06d2011-07-01 16:17:47 +02001570void disk_flush_events(struct gendisk *disk, unsigned int mask)
Tejun Heo77ea8872010-12-08 20:57:37 +01001571{
Tejun Heoa9dce2a2011-06-09 20:43:54 +02001572 struct disk_events *ev = disk->ev;
Tejun Heoa9dce2a2011-06-09 20:43:54 +02001573
1574 if (!ev)
1575 return;
1576
Tejun Heo85ef06d2011-07-01 16:17:47 +02001577 spin_lock_irq(&ev->lock);
1578 ev->clearing |= mask;
Tejun Heo41f63c52012-08-03 10:30:47 -07001579 if (!ev->block)
Viresh Kumar695588f2013-04-24 17:12:56 +05301580 mod_delayed_work(system_freezable_power_efficient_wq,
1581 &ev->dwork, 0);
Tejun Heo85ef06d2011-07-01 16:17:47 +02001582 spin_unlock_irq(&ev->lock);
Tejun Heo77ea8872010-12-08 20:57:37 +01001583}
Tejun Heo77ea8872010-12-08 20:57:37 +01001584
1585/**
1586 * disk_clear_events - synchronously check, clear and return pending events
1587 * @disk: disk to fetch and clear events from
Masanari Iidada3dae52014-09-09 01:27:23 +09001588 * @mask: mask of events to be fetched and cleared
Tejun Heo77ea8872010-12-08 20:57:37 +01001589 *
1590 * Disk events are synchronously checked and pending events in @mask
1591 * are cleared and returned. This ignores the block count.
1592 *
1593 * CONTEXT:
1594 * Might sleep.
1595 */
1596unsigned int disk_clear_events(struct gendisk *disk, unsigned int mask)
1597{
1598 const struct block_device_operations *bdops = disk->fops;
1599 struct disk_events *ev = disk->ev;
1600 unsigned int pending;
Derek Basehore12c2bdb2012-12-18 12:27:20 -08001601 unsigned int clearing = mask;
Tejun Heo77ea8872010-12-08 20:57:37 +01001602
1603 if (!ev) {
1604 /* for drivers still using the old ->media_changed method */
1605 if ((mask & DISK_EVENT_MEDIA_CHANGE) &&
1606 bdops->media_changed && bdops->media_changed(disk))
1607 return DISK_EVENT_MEDIA_CHANGE;
1608 return 0;
1609 }
1610
Derek Basehore12c2bdb2012-12-18 12:27:20 -08001611 disk_block_events(disk);
1612
1613 /*
1614 * store the union of mask and ev->clearing on the stack so that the
1615 * race with disk_flush_events does not cause ambiguity (ev->clearing
1616 * can still be modified even if events are blocked).
1617 */
Tejun Heo77ea8872010-12-08 20:57:37 +01001618 spin_lock_irq(&ev->lock);
Derek Basehore12c2bdb2012-12-18 12:27:20 -08001619 clearing |= ev->clearing;
1620 ev->clearing = 0;
Tejun Heo77ea8872010-12-08 20:57:37 +01001621 spin_unlock_irq(&ev->lock);
1622
Derek Basehore12c2bdb2012-12-18 12:27:20 -08001623 disk_check_events(ev, &clearing);
Derek Basehoreaea24a82012-12-18 12:27:18 -08001624 /*
Derek Basehore12c2bdb2012-12-18 12:27:20 -08001625 * if ev->clearing is not 0, the disk_flush_events got called in the
1626 * middle of this function, so we want to run the workfn without delay.
Derek Basehoreaea24a82012-12-18 12:27:18 -08001627 */
Derek Basehore12c2bdb2012-12-18 12:27:20 -08001628 __disk_unblock_events(disk, ev->clearing ? true : false);
Tejun Heo77ea8872010-12-08 20:57:37 +01001629
1630 /* then, fetch and clear pending events */
1631 spin_lock_irq(&ev->lock);
Tejun Heo77ea8872010-12-08 20:57:37 +01001632 pending = ev->pending & mask;
1633 ev->pending &= ~mask;
1634 spin_unlock_irq(&ev->lock);
Derek Basehore12c2bdb2012-12-18 12:27:20 -08001635 WARN_ON_ONCE(clearing & mask);
Tejun Heo77ea8872010-12-08 20:57:37 +01001636
1637 return pending;
1638}
1639
Derek Basehore12c2bdb2012-12-18 12:27:20 -08001640/*
1641 * Separate this part out so that a different pointer for clearing_ptr can be
1642 * passed in for disk_clear_events.
1643 */
Tejun Heo77ea8872010-12-08 20:57:37 +01001644static void disk_events_workfn(struct work_struct *work)
1645{
1646 struct delayed_work *dwork = to_delayed_work(work);
1647 struct disk_events *ev = container_of(dwork, struct disk_events, dwork);
Derek Basehore12c2bdb2012-12-18 12:27:20 -08001648
1649 disk_check_events(ev, &ev->clearing);
1650}
1651
1652static void disk_check_events(struct disk_events *ev,
1653 unsigned int *clearing_ptr)
1654{
Tejun Heo77ea8872010-12-08 20:57:37 +01001655 struct gendisk *disk = ev->disk;
1656 char *envp[ARRAY_SIZE(disk_uevents) + 1] = { };
Derek Basehore12c2bdb2012-12-18 12:27:20 -08001657 unsigned int clearing = *clearing_ptr;
Tejun Heo77ea8872010-12-08 20:57:37 +01001658 unsigned int events;
1659 unsigned long intv;
1660 int nr_events = 0, i;
1661
1662 /* check events */
1663 events = disk->fops->check_events(disk, clearing);
1664
1665 /* accumulate pending events and schedule next poll if necessary */
1666 spin_lock_irq(&ev->lock);
1667
1668 events &= ~ev->pending;
1669 ev->pending |= events;
Derek Basehore12c2bdb2012-12-18 12:27:20 -08001670 *clearing_ptr &= ~clearing;
Tejun Heo77ea8872010-12-08 20:57:37 +01001671
1672 intv = disk_events_poll_jiffies(disk);
1673 if (!ev->block && intv)
Viresh Kumar695588f2013-04-24 17:12:56 +05301674 queue_delayed_work(system_freezable_power_efficient_wq,
1675 &ev->dwork, intv);
Tejun Heo77ea8872010-12-08 20:57:37 +01001676
1677 spin_unlock_irq(&ev->lock);
1678
Tejun Heo7c88a162011-04-21 19:43:58 +02001679 /*
1680 * Tell userland about new events. Only the events listed in
1681 * @disk->events are reported. Unlisted events are processed the
1682 * same internally but never get reported to userland.
1683 */
Tejun Heo77ea8872010-12-08 20:57:37 +01001684 for (i = 0; i < ARRAY_SIZE(disk_uevents); i++)
Tejun Heo7c88a162011-04-21 19:43:58 +02001685 if (events & disk->events & (1 << i))
Tejun Heo77ea8872010-12-08 20:57:37 +01001686 envp[nr_events++] = disk_uevents[i];
1687
1688 if (nr_events)
1689 kobject_uevent_env(&disk_to_dev(disk)->kobj, KOBJ_CHANGE, envp);
1690}
1691
1692/*
1693 * A disk events enabled device has the following sysfs nodes under
1694 * its /sys/block/X/ directory.
1695 *
1696 * events : list of all supported events
1697 * events_async : list of events which can be detected w/o polling
1698 * events_poll_msecs : polling interval, 0: disable, -1: system default
1699 */
1700static ssize_t __disk_events_show(unsigned int events, char *buf)
1701{
1702 const char *delim = "";
1703 ssize_t pos = 0;
1704 int i;
1705
1706 for (i = 0; i < ARRAY_SIZE(disk_events_strs); i++)
1707 if (events & (1 << i)) {
1708 pos += sprintf(buf + pos, "%s%s",
1709 delim, disk_events_strs[i]);
1710 delim = " ";
1711 }
1712 if (pos)
1713 pos += sprintf(buf + pos, "\n");
1714 return pos;
1715}
1716
1717static ssize_t disk_events_show(struct device *dev,
1718 struct device_attribute *attr, char *buf)
1719{
1720 struct gendisk *disk = dev_to_disk(dev);
1721
1722 return __disk_events_show(disk->events, buf);
1723}
1724
1725static ssize_t disk_events_async_show(struct device *dev,
1726 struct device_attribute *attr, char *buf)
1727{
1728 struct gendisk *disk = dev_to_disk(dev);
1729
1730 return __disk_events_show(disk->async_events, buf);
1731}
1732
1733static ssize_t disk_events_poll_msecs_show(struct device *dev,
1734 struct device_attribute *attr,
1735 char *buf)
1736{
1737 struct gendisk *disk = dev_to_disk(dev);
1738
1739 return sprintf(buf, "%ld\n", disk->ev->poll_msecs);
1740}
1741
1742static ssize_t disk_events_poll_msecs_store(struct device *dev,
1743 struct device_attribute *attr,
1744 const char *buf, size_t count)
1745{
1746 struct gendisk *disk = dev_to_disk(dev);
1747 long intv;
1748
1749 if (!count || !sscanf(buf, "%ld", &intv))
1750 return -EINVAL;
1751
1752 if (intv < 0 && intv != -1)
1753 return -EINVAL;
1754
Tejun Heoc3af54a2011-06-09 20:43:55 +02001755 disk_block_events(disk);
Tejun Heo77ea8872010-12-08 20:57:37 +01001756 disk->ev->poll_msecs = intv;
1757 __disk_unblock_events(disk, true);
1758
1759 return count;
1760}
1761
1762static const DEVICE_ATTR(events, S_IRUGO, disk_events_show, NULL);
1763static const DEVICE_ATTR(events_async, S_IRUGO, disk_events_async_show, NULL);
1764static const DEVICE_ATTR(events_poll_msecs, S_IRUGO|S_IWUSR,
1765 disk_events_poll_msecs_show,
1766 disk_events_poll_msecs_store);
1767
1768static const struct attribute *disk_events_attrs[] = {
1769 &dev_attr_events.attr,
1770 &dev_attr_events_async.attr,
1771 &dev_attr_events_poll_msecs.attr,
1772 NULL,
1773};
1774
1775/*
1776 * The default polling interval can be specified by the kernel
1777 * parameter block.events_dfl_poll_msecs which defaults to 0
1778 * (disable). This can also be modified runtime by writing to
1779 * /sys/module/block/events_dfl_poll_msecs.
1780 */
1781static int disk_events_set_dfl_poll_msecs(const char *val,
1782 const struct kernel_param *kp)
1783{
1784 struct disk_events *ev;
1785 int ret;
1786
1787 ret = param_set_ulong(val, kp);
1788 if (ret < 0)
1789 return ret;
1790
1791 mutex_lock(&disk_events_mutex);
1792
1793 list_for_each_entry(ev, &disk_events, node)
Tejun Heo85ef06d2011-07-01 16:17:47 +02001794 disk_flush_events(ev->disk, 0);
Tejun Heo77ea8872010-12-08 20:57:37 +01001795
1796 mutex_unlock(&disk_events_mutex);
1797
1798 return 0;
1799}
1800
1801static const struct kernel_param_ops disk_events_dfl_poll_msecs_param_ops = {
1802 .set = disk_events_set_dfl_poll_msecs,
1803 .get = param_get_ulong,
1804};
1805
1806#undef MODULE_PARAM_PREFIX
1807#define MODULE_PARAM_PREFIX "block."
1808
1809module_param_cb(events_dfl_poll_msecs, &disk_events_dfl_poll_msecs_param_ops,
1810 &disk_events_dfl_poll_msecs, 0644);
1811
1812/*
Stanislaw Gruszka9f53d2fe2012-03-02 10:43:28 +01001813 * disk_{alloc|add|del|release}_events - initialize and destroy disk_events.
Tejun Heo77ea8872010-12-08 20:57:37 +01001814 */
Stanislaw Gruszka9f53d2fe2012-03-02 10:43:28 +01001815static void disk_alloc_events(struct gendisk *disk)
Tejun Heo77ea8872010-12-08 20:57:37 +01001816{
1817 struct disk_events *ev;
1818
Tejun Heo75e3f3e2011-05-26 21:06:50 +02001819 if (!disk->fops->check_events)
Tejun Heo77ea8872010-12-08 20:57:37 +01001820 return;
1821
1822 ev = kzalloc(sizeof(*ev), GFP_KERNEL);
1823 if (!ev) {
1824 pr_warn("%s: failed to initialize events\n", disk->disk_name);
1825 return;
1826 }
1827
Tejun Heo77ea8872010-12-08 20:57:37 +01001828 INIT_LIST_HEAD(&ev->node);
1829 ev->disk = disk;
1830 spin_lock_init(&ev->lock);
Tejun Heofdd514e2011-06-09 20:43:59 +02001831 mutex_init(&ev->block_mutex);
Tejun Heo77ea8872010-12-08 20:57:37 +01001832 ev->block = 1;
1833 ev->poll_msecs = -1;
1834 INIT_DELAYED_WORK(&ev->dwork, disk_events_workfn);
1835
Stanislaw Gruszka9f53d2fe2012-03-02 10:43:28 +01001836 disk->ev = ev;
1837}
1838
1839static void disk_add_events(struct gendisk *disk)
1840{
1841 if (!disk->ev)
1842 return;
1843
1844 /* FIXME: error handling */
1845 if (sysfs_create_files(&disk_to_dev(disk)->kobj, disk_events_attrs) < 0)
1846 pr_warn("%s: failed to create sysfs files for events\n",
1847 disk->disk_name);
1848
Tejun Heo77ea8872010-12-08 20:57:37 +01001849 mutex_lock(&disk_events_mutex);
Stanislaw Gruszka9f53d2fe2012-03-02 10:43:28 +01001850 list_add_tail(&disk->ev->node, &disk_events);
Tejun Heo77ea8872010-12-08 20:57:37 +01001851 mutex_unlock(&disk_events_mutex);
1852
1853 /*
1854 * Block count is initialized to 1 and the following initial
1855 * unblock kicks it into action.
1856 */
1857 __disk_unblock_events(disk, true);
1858}
1859
1860static void disk_del_events(struct gendisk *disk)
1861{
1862 if (!disk->ev)
1863 return;
1864
Tejun Heoc3af54a2011-06-09 20:43:55 +02001865 disk_block_events(disk);
Tejun Heo77ea8872010-12-08 20:57:37 +01001866
1867 mutex_lock(&disk_events_mutex);
1868 list_del_init(&disk->ev->node);
1869 mutex_unlock(&disk_events_mutex);
1870
1871 sysfs_remove_files(&disk_to_dev(disk)->kobj, disk_events_attrs);
1872}
1873
1874static void disk_release_events(struct gendisk *disk)
1875{
1876 /* the block count should be 1 from disk_del_events() */
1877 WARN_ON_ONCE(disk->ev && disk->ev->block != 1);
1878 kfree(disk->ev);
1879}