1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_GENHD_H
3 #define _LINUX_GENHD_H
4
5 /*
6 * genhd.h Copyright (C) 1992 Drew Eckhardt
7 * Generic hard disk header file by
8 * Drew Eckhardt
9 *
10 * <drew@colorado.edu>
11 */
12
13 #include <linux/types.h>
14 #include <linux/kdev_t.h>
15 #include <linux/rcupdate.h>
16 #include <linux/slab.h>
17 #include <linux/percpu-refcount.h>
18 #include <linux/uuid.h>
19
20 #ifdef CONFIG_BLOCK
21
22 #define dev_to_disk(device) container_of((device), struct gendisk, part0.__dev)
23 #define dev_to_part(device) container_of((device), struct hd_struct, __dev)
24 #define disk_to_dev(disk) (&(disk)->part0.__dev)
25 #define part_to_dev(part) (&((part)->__dev))
26
27 extern struct device_type part_type;
28 extern struct kobject *block_depr;
29 extern struct class block_class;
30
31 enum {
32 /* These three have identical behaviour; use the second one if DOS FDISK gets
33 confused about extended/logical partitions starting past cylinder 1023. */
34 DOS_EXTENDED_PARTITION = 5,
35 LINUX_EXTENDED_PARTITION = 0x85,
36 WIN98_EXTENDED_PARTITION = 0x0f,
37
38 SUN_WHOLE_DISK = DOS_EXTENDED_PARTITION,
39
40 LINUX_SWAP_PARTITION = 0x82,
41 LINUX_DATA_PARTITION = 0x83,
42 LINUX_LVM_PARTITION = 0x8e,
43 LINUX_RAID_PARTITION = 0xfd, /* autodetect RAID partition */
44
45 SOLARIS_X86_PARTITION = LINUX_SWAP_PARTITION,
46 NEW_SOLARIS_X86_PARTITION = 0xbf,
47
48 DM6_AUX1PARTITION = 0x51, /* no DDO: use xlated geom */
49 DM6_AUX3PARTITION = 0x53, /* no DDO: use xlated geom */
50 DM6_PARTITION = 0x54, /* has DDO: use xlated geom & offset */
51 EZD_PARTITION = 0x55, /* EZ-DRIVE */
52
53 FREEBSD_PARTITION = 0xa5, /* FreeBSD Partition ID */
54 OPENBSD_PARTITION = 0xa6, /* OpenBSD Partition ID */
55 NETBSD_PARTITION = 0xa9, /* NetBSD Partition ID */
56 BSDI_PARTITION = 0xb7, /* BSDI Partition ID */
57 MINIX_PARTITION = 0x81, /* Minix Partition ID */
58 UNIXWARE_PARTITION = 0x63, /* Same as GNU_HURD and SCO Unix */
59 };
60
61 #define DISK_MAX_PARTS 256
62 #define DISK_NAME_LEN 32
63
64 #include <linux/major.h>
65 #include <linux/device.h>
66 #include <linux/smp.h>
67 #include <linux/string.h>
68 #include <linux/fs.h>
69 #include <linux/workqueue.h>
70
71 struct partition {
72 unsigned char boot_ind; /* 0x80 - active */
73 unsigned char head; /* starting head */
74 unsigned char sector; /* starting sector */
75 unsigned char cyl; /* starting cylinder */
76 unsigned char sys_ind; /* What partition type */
77 unsigned char end_head; /* end head */
78 unsigned char end_sector; /* end sector */
79 unsigned char end_cyl; /* end cylinder */
80 __le32 start_sect; /* starting sector counting from 0 */
81 __le32 nr_sects; /* nr of sectors in partition */
82 } __attribute__((packed));
83
84 struct disk_stats {
85 unsigned long sectors[2]; /* READs and WRITEs */
86 unsigned long ios[2];
87 unsigned long merges[2];
88 unsigned long ticks[2];
89 unsigned long io_ticks;
90 unsigned long time_in_queue;
91 };
92
93 #define PARTITION_META_INFO_VOLNAMELTH 64
94 /*
95 * Enough for the string representation of any kind of UUID plus NULL.
96 * EFI UUID is 36 characters. MSDOS UUID is 11 characters.
97 */
98 #define PARTITION_META_INFO_UUIDLTH (UUID_STRING_LEN + 1)
99
100 struct partition_meta_info {
101 char uuid[PARTITION_META_INFO_UUIDLTH];
102 u8 volname[PARTITION_META_INFO_VOLNAMELTH];
103 };
104
105 struct hd_struct {
106 sector_t start_sect;
107 /*
108 * nr_sects is protected by sequence counter. One might extend a
109 * partition while IO is happening to it and update of nr_sects
110 * can be non-atomic on 32bit machines with 64bit sector_t.
111 */
112 sector_t nr_sects;
113 seqcount_t nr_sects_seq;
114 sector_t alignment_offset;
115 unsigned int discard_alignment;
116 struct device __dev;
117 struct kobject *holder_dir;
118 int policy, partno;
119 struct partition_meta_info *info;
120 #ifdef CONFIG_FAIL_MAKE_REQUEST
121 int make_it_fail;
122 #endif
123 unsigned long stamp;
124 atomic_t in_flight[2];
125 #ifdef CONFIG_SMP
126 struct disk_stats __percpu *dkstats;
127 #else
128 struct disk_stats dkstats;
129 #endif
130 struct percpu_ref ref;
131 struct rcu_head rcu_head;
132 };
133
134 #define GENHD_FL_REMOVABLE 1
135 /* 2 is unused */
136 #define GENHD_FL_MEDIA_CHANGE_NOTIFY 4
137 #define GENHD_FL_CD 8
138 #define GENHD_FL_UP 16
139 #define GENHD_FL_SUPPRESS_PARTITION_INFO 32
140 #define GENHD_FL_EXT_DEVT 64 /* allow extended devt */
141 #define GENHD_FL_NATIVE_CAPACITY 128
142 #define GENHD_FL_BLOCK_EVENTS_ON_EXCL_WRITE 256
143 #define GENHD_FL_NO_PART_SCAN 512
144
145 enum {
146 DISK_EVENT_MEDIA_CHANGE = 1 << 0, /* media changed */
147 DISK_EVENT_EJECT_REQUEST = 1 << 1, /* eject requested */
148 };
149
150 struct disk_part_tbl {
151 struct rcu_head rcu_head;
152 int len;
153 struct hd_struct __rcu *last_lookup;
154 struct hd_struct __rcu *part[];
155 };
156
157 struct disk_events;
158 struct badblocks;
159
160 #if defined(CONFIG_BLK_DEV_INTEGRITY)
161
162 struct blk_integrity {
163 const struct blk_integrity_profile *profile;
164 unsigned char flags;
165 unsigned char tuple_size;
166 unsigned char interval_exp;
167 unsigned char tag_size;
168 };
169
170 #endif /* CONFIG_BLK_DEV_INTEGRITY */
171
172 struct gendisk {
173 /* major, first_minor and minors are input parameters only,
174 * don't use directly. Use disk_devt() and disk_max_parts().
175 */
176 int major; /* major number of driver */
177 int first_minor;
178 int minors; /* maximum number of minors, =1 for
179 * disks that can't be partitioned. */
180
181 char disk_name[DISK_NAME_LEN]; /* name of major driver */
182 char *(*devnode)(struct gendisk *gd, umode_t *mode);
183
184 unsigned int events; /* supported events */
185 unsigned int async_events; /* async events, subset of all */
186
187 /* Array of pointers to partitions indexed by partno.
188 * Protected with matching bdev lock but stat and other
189 * non-critical accesses use RCU. Always access through
190 * helpers.
191 */
192 struct disk_part_tbl __rcu *part_tbl;
193 struct hd_struct part0;
194
195 const struct block_device_operations *fops;
196 struct request_queue *queue;
197 void *private_data;
198
199 int flags;
200 struct kobject *slave_dir;
201
202 struct timer_rand_state *random;
203 atomic_t sync_io; /* RAID */
204 struct disk_events *ev;
205 #ifdef CONFIG_BLK_DEV_INTEGRITY
206 struct kobject integrity_kobj;
207 #endif /* CONFIG_BLK_DEV_INTEGRITY */
208 int node_id;
209 struct badblocks *bb;
210 };
211
part_to_disk(struct hd_struct * part)212 static inline struct gendisk *part_to_disk(struct hd_struct *part)
213 {
214 if (likely(part)) {
215 if (part->partno)
216 return dev_to_disk(part_to_dev(part)->parent);
217 else
218 return dev_to_disk(part_to_dev(part));
219 }
220 return NULL;
221 }
222
disk_max_parts(struct gendisk * disk)223 static inline int disk_max_parts(struct gendisk *disk)
224 {
225 if (disk->flags & GENHD_FL_EXT_DEVT)
226 return DISK_MAX_PARTS;
227 return disk->minors;
228 }
229
disk_part_scan_enabled(struct gendisk * disk)230 static inline bool disk_part_scan_enabled(struct gendisk *disk)
231 {
232 return disk_max_parts(disk) > 1 &&
233 !(disk->flags & GENHD_FL_NO_PART_SCAN);
234 }
235
disk_devt(struct gendisk * disk)236 static inline dev_t disk_devt(struct gendisk *disk)
237 {
238 return disk_to_dev(disk)->devt;
239 }
240
part_devt(struct hd_struct * part)241 static inline dev_t part_devt(struct hd_struct *part)
242 {
243 return part_to_dev(part)->devt;
244 }
245
246 extern struct hd_struct *__disk_get_part(struct gendisk *disk, int partno);
247 extern struct hd_struct *disk_get_part(struct gendisk *disk, int partno);
248
disk_put_part(struct hd_struct * part)249 static inline void disk_put_part(struct hd_struct *part)
250 {
251 if (likely(part))
252 put_device(part_to_dev(part));
253 }
254
255 /*
256 * Smarter partition iterator without context limits.
257 */
258 #define DISK_PITER_REVERSE (1 << 0) /* iterate in the reverse direction */
259 #define DISK_PITER_INCL_EMPTY (1 << 1) /* include 0-sized parts */
260 #define DISK_PITER_INCL_PART0 (1 << 2) /* include partition 0 */
261 #define DISK_PITER_INCL_EMPTY_PART0 (1 << 3) /* include empty partition 0 */
262
263 struct disk_part_iter {
264 struct gendisk *disk;
265 struct hd_struct *part;
266 int idx;
267 unsigned int flags;
268 };
269
270 extern void disk_part_iter_init(struct disk_part_iter *piter,
271 struct gendisk *disk, unsigned int flags);
272 extern struct hd_struct *disk_part_iter_next(struct disk_part_iter *piter);
273 extern void disk_part_iter_exit(struct disk_part_iter *piter);
274
275 extern struct hd_struct *disk_map_sector_rcu(struct gendisk *disk,
276 sector_t sector);
277
278 /*
279 * Macros to operate on percpu disk statistics:
280 *
281 * {disk|part|all}_stat_{add|sub|inc|dec}() modify the stat counters
282 * and should be called between disk_stat_lock() and
283 * disk_stat_unlock().
284 *
285 * part_stat_read() can be called at any time.
286 *
287 * part_stat_{add|set_all}() and {init|free}_part_stats are for
288 * internal use only.
289 */
290 #ifdef CONFIG_SMP
291 #define part_stat_lock() ({ rcu_read_lock(); get_cpu(); })
292 #define part_stat_unlock() do { put_cpu(); rcu_read_unlock(); } while (0)
293
294 #define __part_stat_add(cpu, part, field, addnd) \
295 (per_cpu_ptr((part)->dkstats, (cpu))->field += (addnd))
296
297 #define part_stat_read(part, field) \
298 ({ \
299 typeof((part)->dkstats->field) res = 0; \
300 unsigned int _cpu; \
301 for_each_possible_cpu(_cpu) \
302 res += per_cpu_ptr((part)->dkstats, _cpu)->field; \
303 res; \
304 })
305
part_stat_set_all(struct hd_struct * part,int value)306 static inline void part_stat_set_all(struct hd_struct *part, int value)
307 {
308 int i;
309
310 for_each_possible_cpu(i)
311 memset(per_cpu_ptr(part->dkstats, i), value,
312 sizeof(struct disk_stats));
313 }
314
init_part_stats(struct hd_struct * part)315 static inline int init_part_stats(struct hd_struct *part)
316 {
317 part->dkstats = alloc_percpu(struct disk_stats);
318 if (!part->dkstats)
319 return 0;
320 return 1;
321 }
322
free_part_stats(struct hd_struct * part)323 static inline void free_part_stats(struct hd_struct *part)
324 {
325 free_percpu(part->dkstats);
326 }
327
328 #else /* !CONFIG_SMP */
329 #define part_stat_lock() ({ rcu_read_lock(); 0; })
330 #define part_stat_unlock() rcu_read_unlock()
331
332 #define __part_stat_add(cpu, part, field, addnd) \
333 ((part)->dkstats.field += addnd)
334
335 #define part_stat_read(part, field) ((part)->dkstats.field)
336
part_stat_set_all(struct hd_struct * part,int value)337 static inline void part_stat_set_all(struct hd_struct *part, int value)
338 {
339 memset(&part->dkstats, value, sizeof(struct disk_stats));
340 }
341
init_part_stats(struct hd_struct * part)342 static inline int init_part_stats(struct hd_struct *part)
343 {
344 return 1;
345 }
346
free_part_stats(struct hd_struct * part)347 static inline void free_part_stats(struct hd_struct *part)
348 {
349 }
350
351 #endif /* CONFIG_SMP */
352
353 #define part_stat_add(cpu, part, field, addnd) do { \
354 __part_stat_add((cpu), (part), field, addnd); \
355 if ((part)->partno) \
356 __part_stat_add((cpu), &part_to_disk((part))->part0, \
357 field, addnd); \
358 } while (0)
359
360 #define part_stat_dec(cpu, gendiskp, field) \
361 part_stat_add(cpu, gendiskp, field, -1)
362 #define part_stat_inc(cpu, gendiskp, field) \
363 part_stat_add(cpu, gendiskp, field, 1)
364 #define part_stat_sub(cpu, gendiskp, field, subnd) \
365 part_stat_add(cpu, gendiskp, field, -subnd)
366
367 void part_in_flight(struct request_queue *q, struct hd_struct *part,
368 unsigned int inflight[2]);
369 void part_in_flight_rw(struct request_queue *q, struct hd_struct *part,
370 unsigned int inflight[2]);
371 void part_dec_in_flight(struct request_queue *q, struct hd_struct *part,
372 int rw);
373 void part_inc_in_flight(struct request_queue *q, struct hd_struct *part,
374 int rw);
375
alloc_part_info(struct gendisk * disk)376 static inline struct partition_meta_info *alloc_part_info(struct gendisk *disk)
377 {
378 if (disk)
379 return kzalloc_node(sizeof(struct partition_meta_info),
380 GFP_KERNEL, disk->node_id);
381 return kzalloc(sizeof(struct partition_meta_info), GFP_KERNEL);
382 }
383
free_part_info(struct hd_struct * part)384 static inline void free_part_info(struct hd_struct *part)
385 {
386 kfree(part->info);
387 }
388
389 /* block/blk-core.c */
390 extern void part_round_stats(struct request_queue *q, int cpu, struct hd_struct *part);
391
392 /* block/genhd.c */
393 extern void device_add_disk(struct device *parent, struct gendisk *disk);
add_disk(struct gendisk * disk)394 static inline void add_disk(struct gendisk *disk)
395 {
396 device_add_disk(NULL, disk);
397 }
398
399 extern void del_gendisk(struct gendisk *gp);
400 extern struct gendisk *get_gendisk(dev_t dev, int *partno);
401 extern struct block_device *bdget_disk(struct gendisk *disk, int partno);
402
403 extern void set_device_ro(struct block_device *bdev, int flag);
404 extern void set_disk_ro(struct gendisk *disk, int flag);
405
get_disk_ro(struct gendisk * disk)406 static inline int get_disk_ro(struct gendisk *disk)
407 {
408 return disk->part0.policy;
409 }
410
411 extern void disk_block_events(struct gendisk *disk);
412 extern void disk_unblock_events(struct gendisk *disk);
413 extern void disk_flush_events(struct gendisk *disk, unsigned int mask);
414 extern unsigned int disk_clear_events(struct gendisk *disk, unsigned int mask);
415
416 /* drivers/char/random.c */
417 extern void add_disk_randomness(struct gendisk *disk) __latent_entropy;
418 extern void rand_initialize_disk(struct gendisk *disk);
419
get_start_sect(struct block_device * bdev)420 static inline sector_t get_start_sect(struct block_device *bdev)
421 {
422 return bdev->bd_part->start_sect;
423 }
get_capacity(struct gendisk * disk)424 static inline sector_t get_capacity(struct gendisk *disk)
425 {
426 return disk->part0.nr_sects;
427 }
set_capacity(struct gendisk * disk,sector_t size)428 static inline void set_capacity(struct gendisk *disk, sector_t size)
429 {
430 disk->part0.nr_sects = size;
431 }
432
433 #ifdef CONFIG_SOLARIS_X86_PARTITION
434
435 #define SOLARIS_X86_NUMSLICE 16
436 #define SOLARIS_X86_VTOC_SANE (0x600DDEEEUL)
437
438 struct solaris_x86_slice {
439 __le16 s_tag; /* ID tag of partition */
440 __le16 s_flag; /* permission flags */
441 __le32 s_start; /* start sector no of partition */
442 __le32 s_size; /* # of blocks in partition */
443 };
444
445 struct solaris_x86_vtoc {
446 unsigned int v_bootinfo[3]; /* info needed by mboot (unsupported) */
447 __le32 v_sanity; /* to verify vtoc sanity */
448 __le32 v_version; /* layout version */
449 char v_volume[8]; /* volume name */
450 __le16 v_sectorsz; /* sector size in bytes */
451 __le16 v_nparts; /* number of partitions */
452 unsigned int v_reserved[10]; /* free space */
453 struct solaris_x86_slice
454 v_slice[SOLARIS_X86_NUMSLICE]; /* slice headers */
455 unsigned int timestamp[SOLARIS_X86_NUMSLICE]; /* timestamp (unsupported) */
456 char v_asciilabel[128]; /* for compatibility */
457 };
458
459 #endif /* CONFIG_SOLARIS_X86_PARTITION */
460
461 #ifdef CONFIG_BSD_DISKLABEL
462 /*
463 * BSD disklabel support by Yossi Gottlieb <yogo@math.tau.ac.il>
464 * updated by Marc Espie <Marc.Espie@openbsd.org>
465 */
466
467 /* check against BSD src/sys/sys/disklabel.h for consistency */
468
469 #define BSD_DISKMAGIC (0x82564557UL) /* The disk magic number */
470 #define BSD_MAXPARTITIONS 16
471 #define OPENBSD_MAXPARTITIONS 16
472 #define BSD_FS_UNUSED 0 /* disklabel unused partition entry ID */
473 struct bsd_disklabel {
474 __le32 d_magic; /* the magic number */
475 __s16 d_type; /* drive type */
476 __s16 d_subtype; /* controller/d_type specific */
477 char d_typename[16]; /* type name, e.g. "eagle" */
478 char d_packname[16]; /* pack identifier */
479 __u32 d_secsize; /* # of bytes per sector */
480 __u32 d_nsectors; /* # of data sectors per track */
481 __u32 d_ntracks; /* # of tracks per cylinder */
482 __u32 d_ncylinders; /* # of data cylinders per unit */
483 __u32 d_secpercyl; /* # of data sectors per cylinder */
484 __u32 d_secperunit; /* # of data sectors per unit */
485 __u16 d_sparespertrack; /* # of spare sectors per track */
486 __u16 d_sparespercyl; /* # of spare sectors per cylinder */
487 __u32 d_acylinders; /* # of alt. cylinders per unit */
488 __u16 d_rpm; /* rotational speed */
489 __u16 d_interleave; /* hardware sector interleave */
490 __u16 d_trackskew; /* sector 0 skew, per track */
491 __u16 d_cylskew; /* sector 0 skew, per cylinder */
492 __u32 d_headswitch; /* head switch time, usec */
493 __u32 d_trkseek; /* track-to-track seek, usec */
494 __u32 d_flags; /* generic flags */
495 #define NDDATA 5
496 __u32 d_drivedata[NDDATA]; /* drive-type specific information */
497 #define NSPARE 5
498 __u32 d_spare[NSPARE]; /* reserved for future use */
499 __le32 d_magic2; /* the magic number (again) */
500 __le16 d_checksum; /* xor of data incl. partitions */
501
502 /* filesystem and partition information: */
503 __le16 d_npartitions; /* number of partitions in following */
504 __le32 d_bbsize; /* size of boot area at sn0, bytes */
505 __le32 d_sbsize; /* max size of fs superblock, bytes */
506 struct bsd_partition { /* the partition table */
507 __le32 p_size; /* number of sectors in partition */
508 __le32 p_offset; /* starting sector */
509 __le32 p_fsize; /* filesystem basic fragment size */
510 __u8 p_fstype; /* filesystem type, see below */
511 __u8 p_frag; /* filesystem fragments per block */
512 __le16 p_cpg; /* filesystem cylinders per group */
513 } d_partitions[BSD_MAXPARTITIONS]; /* actually may be more */
514 };
515
516 #endif /* CONFIG_BSD_DISKLABEL */
517
518 #ifdef CONFIG_UNIXWARE_DISKLABEL
519 /*
520 * Unixware slices support by Andrzej Krzysztofowicz <ankry@mif.pg.gda.pl>
521 * and Krzysztof G. Baranowski <kgb@knm.org.pl>
522 */
523
524 #define UNIXWARE_DISKMAGIC (0xCA5E600DUL) /* The disk magic number */
525 #define UNIXWARE_DISKMAGIC2 (0x600DDEEEUL) /* The slice table magic nr */
526 #define UNIXWARE_NUMSLICE 16
527 #define UNIXWARE_FS_UNUSED 0 /* Unused slice entry ID */
528
529 struct unixware_slice {
530 __le16 s_label; /* label */
531 __le16 s_flags; /* permission flags */
532 __le32 start_sect; /* starting sector */
533 __le32 nr_sects; /* number of sectors in slice */
534 };
535
536 struct unixware_disklabel {
537 __le32 d_type; /* drive type */
538 __le32 d_magic; /* the magic number */
539 __le32 d_version; /* version number */
540 char d_serial[12]; /* serial number of the device */
541 __le32 d_ncylinders; /* # of data cylinders per device */
542 __le32 d_ntracks; /* # of tracks per cylinder */
543 __le32 d_nsectors; /* # of data sectors per track */
544 __le32 d_secsize; /* # of bytes per sector */
545 __le32 d_part_start; /* # of first sector of this partition */
546 __le32 d_unknown1[12]; /* ? */
547 __le32 d_alt_tbl; /* byte offset of alternate table */
548 __le32 d_alt_len; /* byte length of alternate table */
549 __le32 d_phys_cyl; /* # of physical cylinders per device */
550 __le32 d_phys_trk; /* # of physical tracks per cylinder */
551 __le32 d_phys_sec; /* # of physical sectors per track */
552 __le32 d_phys_bytes; /* # of physical bytes per sector */
553 __le32 d_unknown2; /* ? */
554 __le32 d_unknown3; /* ? */
555 __le32 d_pad[8]; /* pad */
556
557 struct unixware_vtoc {
558 __le32 v_magic; /* the magic number */
559 __le32 v_version; /* version number */
560 char v_name[8]; /* volume name */
561 __le16 v_nslices; /* # of slices */
562 __le16 v_unknown1; /* ? */
563 __le32 v_reserved[10]; /* reserved */
564 struct unixware_slice
565 v_slice[UNIXWARE_NUMSLICE]; /* slice headers */
566 } vtoc;
567
568 }; /* 408 */
569
570 #endif /* CONFIG_UNIXWARE_DISKLABEL */
571
572 #ifdef CONFIG_MINIX_SUBPARTITION
573 # define MINIX_NR_SUBPARTITIONS 4
574 #endif /* CONFIG_MINIX_SUBPARTITION */
575
576 #define ADDPART_FLAG_NONE 0
577 #define ADDPART_FLAG_RAID 1
578 #define ADDPART_FLAG_WHOLEDISK 2
579
580 extern int blk_alloc_devt(struct hd_struct *part, dev_t *devt);
581 extern void blk_free_devt(dev_t devt);
582 extern dev_t blk_lookup_devt(const char *name, int partno);
583 extern char *disk_name (struct gendisk *hd, int partno, char *buf);
584
585 extern int disk_expand_part_tbl(struct gendisk *disk, int target);
586 extern int rescan_partitions(struct gendisk *disk, struct block_device *bdev);
587 extern int invalidate_partitions(struct gendisk *disk, struct block_device *bdev);
588 extern struct hd_struct * __must_check add_partition(struct gendisk *disk,
589 int partno, sector_t start,
590 sector_t len, int flags,
591 struct partition_meta_info
592 *info);
593 extern void __delete_partition(struct percpu_ref *);
594 extern void delete_partition(struct gendisk *, int);
595 extern void printk_all_partitions(void);
596
597 extern struct gendisk *alloc_disk_node(int minors, int node_id);
598 extern struct gendisk *alloc_disk(int minors);
599 extern struct kobject *get_disk(struct gendisk *disk);
600 extern void put_disk(struct gendisk *disk);
601 extern void blk_register_region(dev_t devt, unsigned long range,
602 struct module *module,
603 struct kobject *(*probe)(dev_t, int *, void *),
604 int (*lock)(dev_t, void *),
605 void *data);
606 extern void blk_unregister_region(dev_t devt, unsigned long range);
607
608 extern ssize_t part_size_show(struct device *dev,
609 struct device_attribute *attr, char *buf);
610 extern ssize_t part_stat_show(struct device *dev,
611 struct device_attribute *attr, char *buf);
612 extern ssize_t part_inflight_show(struct device *dev,
613 struct device_attribute *attr, char *buf);
614 #ifdef CONFIG_FAIL_MAKE_REQUEST
615 extern ssize_t part_fail_show(struct device *dev,
616 struct device_attribute *attr, char *buf);
617 extern ssize_t part_fail_store(struct device *dev,
618 struct device_attribute *attr,
619 const char *buf, size_t count);
620 #endif /* CONFIG_FAIL_MAKE_REQUEST */
621
hd_ref_init(struct hd_struct * part)622 static inline int hd_ref_init(struct hd_struct *part)
623 {
624 if (percpu_ref_init(&part->ref, __delete_partition, 0,
625 GFP_KERNEL))
626 return -ENOMEM;
627 return 0;
628 }
629
hd_struct_get(struct hd_struct * part)630 static inline void hd_struct_get(struct hd_struct *part)
631 {
632 percpu_ref_get(&part->ref);
633 }
634
hd_struct_try_get(struct hd_struct * part)635 static inline int hd_struct_try_get(struct hd_struct *part)
636 {
637 return percpu_ref_tryget_live(&part->ref);
638 }
639
hd_struct_put(struct hd_struct * part)640 static inline void hd_struct_put(struct hd_struct *part)
641 {
642 percpu_ref_put(&part->ref);
643 }
644
hd_struct_kill(struct hd_struct * part)645 static inline void hd_struct_kill(struct hd_struct *part)
646 {
647 percpu_ref_kill(&part->ref);
648 }
649
hd_free_part(struct hd_struct * part)650 static inline void hd_free_part(struct hd_struct *part)
651 {
652 free_part_stats(part);
653 free_part_info(part);
654 percpu_ref_exit(&part->ref);
655 }
656
657 /*
658 * Any access of part->nr_sects which is not protected by partition
659 * bd_mutex or gendisk bdev bd_mutex, should be done using this
660 * accessor function.
661 *
662 * Code written along the lines of i_size_read() and i_size_write().
663 * CONFIG_PREEMPT case optimizes the case of UP kernel with preemption
664 * on.
665 */
part_nr_sects_read(struct hd_struct * part)666 static inline sector_t part_nr_sects_read(struct hd_struct *part)
667 {
668 #if BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_SMP)
669 sector_t nr_sects;
670 unsigned seq;
671 do {
672 seq = read_seqcount_begin(&part->nr_sects_seq);
673 nr_sects = part->nr_sects;
674 } while (read_seqcount_retry(&part->nr_sects_seq, seq));
675 return nr_sects;
676 #elif BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_PREEMPT)
677 sector_t nr_sects;
678
679 preempt_disable();
680 nr_sects = part->nr_sects;
681 preempt_enable();
682 return nr_sects;
683 #else
684 return part->nr_sects;
685 #endif
686 }
687
688 /*
689 * Should be called with mutex lock held (typically bd_mutex) of partition
690 * to provide mutual exlusion among writers otherwise seqcount might be
691 * left in wrong state leaving the readers spinning infinitely.
692 */
part_nr_sects_write(struct hd_struct * part,sector_t size)693 static inline void part_nr_sects_write(struct hd_struct *part, sector_t size)
694 {
695 #if BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_SMP)
696 write_seqcount_begin(&part->nr_sects_seq);
697 part->nr_sects = size;
698 write_seqcount_end(&part->nr_sects_seq);
699 #elif BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_PREEMPT)
700 preempt_disable();
701 part->nr_sects = size;
702 preempt_enable();
703 #else
704 part->nr_sects = size;
705 #endif
706 }
707
708 #if defined(CONFIG_BLK_DEV_INTEGRITY)
709 extern void blk_integrity_add(struct gendisk *);
710 extern void blk_integrity_del(struct gendisk *);
711 #else /* CONFIG_BLK_DEV_INTEGRITY */
blk_integrity_add(struct gendisk * disk)712 static inline void blk_integrity_add(struct gendisk *disk) { }
blk_integrity_del(struct gendisk * disk)713 static inline void blk_integrity_del(struct gendisk *disk) { }
714 #endif /* CONFIG_BLK_DEV_INTEGRITY */
715
716 #else /* CONFIG_BLOCK */
717
printk_all_partitions(void)718 static inline void printk_all_partitions(void) { }
719
blk_lookup_devt(const char * name,int partno)720 static inline dev_t blk_lookup_devt(const char *name, int partno)
721 {
722 dev_t devt = MKDEV(0, 0);
723 return devt;
724 }
725 #endif /* CONFIG_BLOCK */
726
727 #endif /* _LINUX_GENHD_H */
728