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 #include <linux/blk_types.h>
20
21 #ifdef CONFIG_BLOCK
22
23 #define dev_to_disk(device) container_of((device), struct gendisk, part0.__dev)
24 #define dev_to_part(device) container_of((device), struct hd_struct, __dev)
25 #define disk_to_dev(disk) (&(disk)->part0.__dev)
26 #define part_to_dev(part) (&((part)->__dev))
27
28 extern struct device_type part_type;
29 extern struct kobject *block_depr;
30 extern struct class block_class;
31
32 enum {
33 /* These three have identical behaviour; use the second one if DOS FDISK gets
34 confused about extended/logical partitions starting past cylinder 1023. */
35 DOS_EXTENDED_PARTITION = 5,
36 LINUX_EXTENDED_PARTITION = 0x85,
37 WIN98_EXTENDED_PARTITION = 0x0f,
38
39 SUN_WHOLE_DISK = DOS_EXTENDED_PARTITION,
40
41 LINUX_SWAP_PARTITION = 0x82,
42 LINUX_DATA_PARTITION = 0x83,
43 LINUX_LVM_PARTITION = 0x8e,
44 LINUX_RAID_PARTITION = 0xfd, /* autodetect RAID partition */
45
46 SOLARIS_X86_PARTITION = LINUX_SWAP_PARTITION,
47 NEW_SOLARIS_X86_PARTITION = 0xbf,
48
49 DM6_AUX1PARTITION = 0x51, /* no DDO: use xlated geom */
50 DM6_AUX3PARTITION = 0x53, /* no DDO: use xlated geom */
51 DM6_PARTITION = 0x54, /* has DDO: use xlated geom & offset */
52 EZD_PARTITION = 0x55, /* EZ-DRIVE */
53
54 FREEBSD_PARTITION = 0xa5, /* FreeBSD Partition ID */
55 OPENBSD_PARTITION = 0xa6, /* OpenBSD Partition ID */
56 NETBSD_PARTITION = 0xa9, /* NetBSD Partition ID */
57 BSDI_PARTITION = 0xb7, /* BSDI Partition ID */
58 MINIX_PARTITION = 0x81, /* Minix Partition ID */
59 UNIXWARE_PARTITION = 0x63, /* Same as GNU_HURD and SCO Unix */
60 };
61
62 #define DISK_MAX_PARTS 256
63 #define DISK_NAME_LEN 32
64
65 #include <linux/major.h>
66 #include <linux/device.h>
67 #include <linux/smp.h>
68 #include <linux/string.h>
69 #include <linux/fs.h>
70 #include <linux/workqueue.h>
71
72 struct partition {
73 unsigned char boot_ind; /* 0x80 - active */
74 unsigned char head; /* starting head */
75 unsigned char sector; /* starting sector */
76 unsigned char cyl; /* starting cylinder */
77 unsigned char sys_ind; /* What partition type */
78 unsigned char end_head; /* end head */
79 unsigned char end_sector; /* end sector */
80 unsigned char end_cyl; /* end cylinder */
81 __le32 start_sect; /* starting sector counting from 0 */
82 __le32 nr_sects; /* nr of sectors in partition */
83 } __attribute__((packed));
84
85 struct disk_stats {
86 u64 nsecs[NR_STAT_GROUPS];
87 unsigned long sectors[NR_STAT_GROUPS];
88 unsigned long ios[NR_STAT_GROUPS];
89 unsigned long merges[NR_STAT_GROUPS];
90 unsigned long io_ticks;
91 unsigned long time_in_queue;
92 };
93
94 #define PARTITION_META_INFO_VOLNAMELTH 64
95 /*
96 * Enough for the string representation of any kind of UUID plus NULL.
97 * EFI UUID is 36 characters. MSDOS UUID is 11 characters.
98 */
99 #define PARTITION_META_INFO_UUIDLTH (UUID_STRING_LEN + 1)
100
101 struct partition_meta_info {
102 char uuid[PARTITION_META_INFO_UUIDLTH];
103 u8 volname[PARTITION_META_INFO_VOLNAMELTH];
104 };
105
106 struct hd_struct {
107 sector_t start_sect;
108 /*
109 * nr_sects is protected by sequence counter. One might extend a
110 * partition while IO is happening to it and update of nr_sects
111 * can be non-atomic on 32bit machines with 64bit sector_t.
112 */
113 sector_t nr_sects;
114 seqcount_t nr_sects_seq;
115 sector_t alignment_offset;
116 unsigned int discard_alignment;
117 struct device __dev;
118 struct kobject *holder_dir;
119 int policy, partno;
120 struct partition_meta_info *info;
121 #ifdef CONFIG_FAIL_MAKE_REQUEST
122 int make_it_fail;
123 #endif
124 unsigned long stamp;
125 atomic_t in_flight[2];
126 #ifdef CONFIG_SMP
127 struct disk_stats __percpu *dkstats;
128 #else
129 struct disk_stats dkstats;
130 #endif
131 struct percpu_ref ref;
132 struct rcu_head rcu_head;
133 };
134
135 #define GENHD_FL_REMOVABLE 1
136 /* 2 is unused */
137 #define GENHD_FL_MEDIA_CHANGE_NOTIFY 4
138 #define GENHD_FL_CD 8
139 #define GENHD_FL_UP 16
140 #define GENHD_FL_SUPPRESS_PARTITION_INFO 32
141 #define GENHD_FL_EXT_DEVT 64 /* allow extended devt */
142 #define GENHD_FL_NATIVE_CAPACITY 128
143 #define GENHD_FL_BLOCK_EVENTS_ON_EXCL_WRITE 256
144 #define GENHD_FL_NO_PART_SCAN 512
145 #define GENHD_FL_HIDDEN 1024
146
147 enum {
148 DISK_EVENT_MEDIA_CHANGE = 1 << 0, /* media changed */
149 DISK_EVENT_EJECT_REQUEST = 1 << 1, /* eject requested */
150 };
151
152 struct disk_part_tbl {
153 struct rcu_head rcu_head;
154 int len;
155 struct hd_struct __rcu *last_lookup;
156 struct hd_struct __rcu *part[];
157 };
158
159 struct disk_events;
160 struct badblocks;
161
162 #if defined(CONFIG_BLK_DEV_INTEGRITY)
163
164 struct blk_integrity {
165 const struct blk_integrity_profile *profile;
166 unsigned char flags;
167 unsigned char tuple_size;
168 unsigned char interval_exp;
169 unsigned char tag_size;
170 };
171
172 #endif /* CONFIG_BLK_DEV_INTEGRITY */
173
174 struct gendisk {
175 /* major, first_minor and minors are input parameters only,
176 * don't use directly. Use disk_devt() and disk_max_parts().
177 */
178 int major; /* major number of driver */
179 int first_minor;
180 int minors; /* maximum number of minors, =1 for
181 * disks that can't be partitioned. */
182
183 char disk_name[DISK_NAME_LEN]; /* name of major driver */
184 char *(*devnode)(struct gendisk *gd, umode_t *mode);
185
186 unsigned int events; /* supported events */
187 unsigned int async_events; /* async events, subset of all */
188
189 /* Array of pointers to partitions indexed by partno.
190 * Protected with matching bdev lock but stat and other
191 * non-critical accesses use RCU. Always access through
192 * helpers.
193 */
194 struct disk_part_tbl __rcu *part_tbl;
195 struct hd_struct part0;
196
197 const struct block_device_operations *fops;
198 struct request_queue *queue;
199 void *private_data;
200
201 int flags;
202 struct rw_semaphore lookup_sem;
203 struct kobject *slave_dir;
204
205 struct timer_rand_state *random;
206 atomic_t sync_io; /* RAID */
207 struct disk_events *ev;
208 #ifdef CONFIG_BLK_DEV_INTEGRITY
209 struct kobject integrity_kobj;
210 #endif /* CONFIG_BLK_DEV_INTEGRITY */
211 int node_id;
212 struct badblocks *bb;
213 struct lockdep_map lockdep_map;
214 };
215
part_to_disk(struct hd_struct * part)216 static inline struct gendisk *part_to_disk(struct hd_struct *part)
217 {
218 if (likely(part)) {
219 if (part->partno)
220 return dev_to_disk(part_to_dev(part)->parent);
221 else
222 return dev_to_disk(part_to_dev(part));
223 }
224 return NULL;
225 }
226
disk_max_parts(struct gendisk * disk)227 static inline int disk_max_parts(struct gendisk *disk)
228 {
229 if (disk->flags & GENHD_FL_EXT_DEVT)
230 return DISK_MAX_PARTS;
231 return disk->minors;
232 }
233
disk_part_scan_enabled(struct gendisk * disk)234 static inline bool disk_part_scan_enabled(struct gendisk *disk)
235 {
236 return disk_max_parts(disk) > 1 &&
237 !(disk->flags & GENHD_FL_NO_PART_SCAN);
238 }
239
disk_devt(struct gendisk * disk)240 static inline dev_t disk_devt(struct gendisk *disk)
241 {
242 return MKDEV(disk->major, disk->first_minor);
243 }
244
part_devt(struct hd_struct * part)245 static inline dev_t part_devt(struct hd_struct *part)
246 {
247 return part_to_dev(part)->devt;
248 }
249
250 extern struct hd_struct *__disk_get_part(struct gendisk *disk, int partno);
251 extern struct hd_struct *disk_get_part(struct gendisk *disk, int partno);
252
disk_put_part(struct hd_struct * part)253 static inline void disk_put_part(struct hd_struct *part)
254 {
255 if (likely(part))
256 put_device(part_to_dev(part));
257 }
258
259 /*
260 * Smarter partition iterator without context limits.
261 */
262 #define DISK_PITER_REVERSE (1 << 0) /* iterate in the reverse direction */
263 #define DISK_PITER_INCL_EMPTY (1 << 1) /* include 0-sized parts */
264 #define DISK_PITER_INCL_PART0 (1 << 2) /* include partition 0 */
265 #define DISK_PITER_INCL_EMPTY_PART0 (1 << 3) /* include empty partition 0 */
266
267 struct disk_part_iter {
268 struct gendisk *disk;
269 struct hd_struct *part;
270 int idx;
271 unsigned int flags;
272 };
273
274 extern void disk_part_iter_init(struct disk_part_iter *piter,
275 struct gendisk *disk, unsigned int flags);
276 extern struct hd_struct *disk_part_iter_next(struct disk_part_iter *piter);
277 extern void disk_part_iter_exit(struct disk_part_iter *piter);
278
279 extern struct hd_struct *disk_map_sector_rcu(struct gendisk *disk,
280 sector_t sector);
281
282 /*
283 * Macros to operate on percpu disk statistics:
284 *
285 * {disk|part|all}_stat_{add|sub|inc|dec}() modify the stat counters
286 * and should be called between disk_stat_lock() and
287 * disk_stat_unlock().
288 *
289 * part_stat_read() can be called at any time.
290 *
291 * part_stat_{add|set_all}() and {init|free}_part_stats are for
292 * internal use only.
293 */
294 #ifdef CONFIG_SMP
295 #define part_stat_lock() ({ rcu_read_lock(); get_cpu(); })
296 #define part_stat_unlock() do { put_cpu(); rcu_read_unlock(); } while (0)
297
298 #define __part_stat_add(cpu, part, field, addnd) \
299 (per_cpu_ptr((part)->dkstats, (cpu))->field += (addnd))
300
301 #define part_stat_read(part, field) \
302 ({ \
303 typeof((part)->dkstats->field) res = 0; \
304 unsigned int _cpu; \
305 for_each_possible_cpu(_cpu) \
306 res += per_cpu_ptr((part)->dkstats, _cpu)->field; \
307 res; \
308 })
309
part_stat_set_all(struct hd_struct * part,int value)310 static inline void part_stat_set_all(struct hd_struct *part, int value)
311 {
312 int i;
313
314 for_each_possible_cpu(i)
315 memset(per_cpu_ptr(part->dkstats, i), value,
316 sizeof(struct disk_stats));
317 }
318
init_part_stats(struct hd_struct * part)319 static inline int init_part_stats(struct hd_struct *part)
320 {
321 part->dkstats = alloc_percpu(struct disk_stats);
322 if (!part->dkstats)
323 return 0;
324 return 1;
325 }
326
free_part_stats(struct hd_struct * part)327 static inline void free_part_stats(struct hd_struct *part)
328 {
329 free_percpu(part->dkstats);
330 }
331
332 #else /* !CONFIG_SMP */
333 #define part_stat_lock() ({ rcu_read_lock(); 0; })
334 #define part_stat_unlock() rcu_read_unlock()
335
336 #define __part_stat_add(cpu, part, field, addnd) \
337 ((part)->dkstats.field += addnd)
338
339 #define part_stat_read(part, field) ((part)->dkstats.field)
340
part_stat_set_all(struct hd_struct * part,int value)341 static inline void part_stat_set_all(struct hd_struct *part, int value)
342 {
343 memset(&part->dkstats, value, sizeof(struct disk_stats));
344 }
345
init_part_stats(struct hd_struct * part)346 static inline int init_part_stats(struct hd_struct *part)
347 {
348 return 1;
349 }
350
free_part_stats(struct hd_struct * part)351 static inline void free_part_stats(struct hd_struct *part)
352 {
353 }
354
355 #endif /* CONFIG_SMP */
356
357 #define part_stat_read_msecs(part, which) \
358 div_u64(part_stat_read(part, nsecs[which]), NSEC_PER_MSEC)
359
360 #define part_stat_read_accum(part, field) \
361 (part_stat_read(part, field[STAT_READ]) + \
362 part_stat_read(part, field[STAT_WRITE]) + \
363 part_stat_read(part, field[STAT_DISCARD]))
364
365 #define part_stat_add(cpu, part, field, addnd) do { \
366 __part_stat_add((cpu), (part), field, addnd); \
367 if ((part)->partno) \
368 __part_stat_add((cpu), &part_to_disk((part))->part0, \
369 field, addnd); \
370 } while (0)
371
372 #define part_stat_dec(cpu, gendiskp, field) \
373 part_stat_add(cpu, gendiskp, field, -1)
374 #define part_stat_inc(cpu, gendiskp, field) \
375 part_stat_add(cpu, gendiskp, field, 1)
376 #define part_stat_sub(cpu, gendiskp, field, subnd) \
377 part_stat_add(cpu, gendiskp, field, -subnd)
378
379 void part_in_flight(struct request_queue *q, struct hd_struct *part,
380 unsigned int inflight[2]);
381 void part_in_flight_rw(struct request_queue *q, struct hd_struct *part,
382 unsigned int inflight[2]);
383 void part_dec_in_flight(struct request_queue *q, struct hd_struct *part,
384 int rw);
385 void part_inc_in_flight(struct request_queue *q, struct hd_struct *part,
386 int rw);
387
alloc_part_info(struct gendisk * disk)388 static inline struct partition_meta_info *alloc_part_info(struct gendisk *disk)
389 {
390 if (disk)
391 return kzalloc_node(sizeof(struct partition_meta_info),
392 GFP_KERNEL, disk->node_id);
393 return kzalloc(sizeof(struct partition_meta_info), GFP_KERNEL);
394 }
395
free_part_info(struct hd_struct * part)396 static inline void free_part_info(struct hd_struct *part)
397 {
398 kfree(part->info);
399 }
400
401 /* block/blk-core.c */
402 extern void part_round_stats(struct request_queue *q, int cpu, struct hd_struct *part);
403
404 /* block/genhd.c */
405 extern void device_add_disk(struct device *parent, struct gendisk *disk);
add_disk(struct gendisk * disk)406 static inline void add_disk(struct gendisk *disk)
407 {
408 device_add_disk(NULL, disk);
409 }
410 extern void device_add_disk_no_queue_reg(struct device *parent, struct gendisk *disk);
add_disk_no_queue_reg(struct gendisk * disk)411 static inline void add_disk_no_queue_reg(struct gendisk *disk)
412 {
413 device_add_disk_no_queue_reg(NULL, disk);
414 }
415
416 extern void del_gendisk(struct gendisk *gp);
417 extern struct gendisk *get_gendisk(dev_t dev, int *partno);
418 extern struct block_device *bdget_disk(struct gendisk *disk, int partno);
419
420 extern void set_device_ro(struct block_device *bdev, int flag);
421 extern void set_disk_ro(struct gendisk *disk, int flag);
422
get_disk_ro(struct gendisk * disk)423 static inline int get_disk_ro(struct gendisk *disk)
424 {
425 return disk->part0.policy;
426 }
427
428 extern void disk_block_events(struct gendisk *disk);
429 extern void disk_unblock_events(struct gendisk *disk);
430 extern void disk_flush_events(struct gendisk *disk, unsigned int mask);
431 extern unsigned int disk_clear_events(struct gendisk *disk, unsigned int mask);
432
433 /* drivers/char/random.c */
434 extern void add_disk_randomness(struct gendisk *disk) __latent_entropy;
435 extern void rand_initialize_disk(struct gendisk *disk);
436
get_start_sect(struct block_device * bdev)437 static inline sector_t get_start_sect(struct block_device *bdev)
438 {
439 return bdev->bd_part->start_sect;
440 }
get_capacity(struct gendisk * disk)441 static inline sector_t get_capacity(struct gendisk *disk)
442 {
443 return disk->part0.nr_sects;
444 }
set_capacity(struct gendisk * disk,sector_t size)445 static inline void set_capacity(struct gendisk *disk, sector_t size)
446 {
447 disk->part0.nr_sects = size;
448 }
449
450 #ifdef CONFIG_SOLARIS_X86_PARTITION
451
452 #define SOLARIS_X86_NUMSLICE 16
453 #define SOLARIS_X86_VTOC_SANE (0x600DDEEEUL)
454
455 struct solaris_x86_slice {
456 __le16 s_tag; /* ID tag of partition */
457 __le16 s_flag; /* permission flags */
458 __le32 s_start; /* start sector no of partition */
459 __le32 s_size; /* # of blocks in partition */
460 };
461
462 struct solaris_x86_vtoc {
463 unsigned int v_bootinfo[3]; /* info needed by mboot (unsupported) */
464 __le32 v_sanity; /* to verify vtoc sanity */
465 __le32 v_version; /* layout version */
466 char v_volume[8]; /* volume name */
467 __le16 v_sectorsz; /* sector size in bytes */
468 __le16 v_nparts; /* number of partitions */
469 unsigned int v_reserved[10]; /* free space */
470 struct solaris_x86_slice
471 v_slice[SOLARIS_X86_NUMSLICE]; /* slice headers */
472 unsigned int timestamp[SOLARIS_X86_NUMSLICE]; /* timestamp (unsupported) */
473 char v_asciilabel[128]; /* for compatibility */
474 };
475
476 #endif /* CONFIG_SOLARIS_X86_PARTITION */
477
478 #ifdef CONFIG_BSD_DISKLABEL
479 /*
480 * BSD disklabel support by Yossi Gottlieb <yogo@math.tau.ac.il>
481 * updated by Marc Espie <Marc.Espie@openbsd.org>
482 */
483
484 /* check against BSD src/sys/sys/disklabel.h for consistency */
485
486 #define BSD_DISKMAGIC (0x82564557UL) /* The disk magic number */
487 #define BSD_MAXPARTITIONS 16
488 #define OPENBSD_MAXPARTITIONS 16
489 #define BSD_FS_UNUSED 0 /* disklabel unused partition entry ID */
490 struct bsd_disklabel {
491 __le32 d_magic; /* the magic number */
492 __s16 d_type; /* drive type */
493 __s16 d_subtype; /* controller/d_type specific */
494 char d_typename[16]; /* type name, e.g. "eagle" */
495 char d_packname[16]; /* pack identifier */
496 __u32 d_secsize; /* # of bytes per sector */
497 __u32 d_nsectors; /* # of data sectors per track */
498 __u32 d_ntracks; /* # of tracks per cylinder */
499 __u32 d_ncylinders; /* # of data cylinders per unit */
500 __u32 d_secpercyl; /* # of data sectors per cylinder */
501 __u32 d_secperunit; /* # of data sectors per unit */
502 __u16 d_sparespertrack; /* # of spare sectors per track */
503 __u16 d_sparespercyl; /* # of spare sectors per cylinder */
504 __u32 d_acylinders; /* # of alt. cylinders per unit */
505 __u16 d_rpm; /* rotational speed */
506 __u16 d_interleave; /* hardware sector interleave */
507 __u16 d_trackskew; /* sector 0 skew, per track */
508 __u16 d_cylskew; /* sector 0 skew, per cylinder */
509 __u32 d_headswitch; /* head switch time, usec */
510 __u32 d_trkseek; /* track-to-track seek, usec */
511 __u32 d_flags; /* generic flags */
512 #define NDDATA 5
513 __u32 d_drivedata[NDDATA]; /* drive-type specific information */
514 #define NSPARE 5
515 __u32 d_spare[NSPARE]; /* reserved for future use */
516 __le32 d_magic2; /* the magic number (again) */
517 __le16 d_checksum; /* xor of data incl. partitions */
518
519 /* filesystem and partition information: */
520 __le16 d_npartitions; /* number of partitions in following */
521 __le32 d_bbsize; /* size of boot area at sn0, bytes */
522 __le32 d_sbsize; /* max size of fs superblock, bytes */
523 struct bsd_partition { /* the partition table */
524 __le32 p_size; /* number of sectors in partition */
525 __le32 p_offset; /* starting sector */
526 __le32 p_fsize; /* filesystem basic fragment size */
527 __u8 p_fstype; /* filesystem type, see below */
528 __u8 p_frag; /* filesystem fragments per block */
529 __le16 p_cpg; /* filesystem cylinders per group */
530 } d_partitions[BSD_MAXPARTITIONS]; /* actually may be more */
531 };
532
533 #endif /* CONFIG_BSD_DISKLABEL */
534
535 #ifdef CONFIG_UNIXWARE_DISKLABEL
536 /*
537 * Unixware slices support by Andrzej Krzysztofowicz <ankry@mif.pg.gda.pl>
538 * and Krzysztof G. Baranowski <kgb@knm.org.pl>
539 */
540
541 #define UNIXWARE_DISKMAGIC (0xCA5E600DUL) /* The disk magic number */
542 #define UNIXWARE_DISKMAGIC2 (0x600DDEEEUL) /* The slice table magic nr */
543 #define UNIXWARE_NUMSLICE 16
544 #define UNIXWARE_FS_UNUSED 0 /* Unused slice entry ID */
545
546 struct unixware_slice {
547 __le16 s_label; /* label */
548 __le16 s_flags; /* permission flags */
549 __le32 start_sect; /* starting sector */
550 __le32 nr_sects; /* number of sectors in slice */
551 };
552
553 struct unixware_disklabel {
554 __le32 d_type; /* drive type */
555 __le32 d_magic; /* the magic number */
556 __le32 d_version; /* version number */
557 char d_serial[12]; /* serial number of the device */
558 __le32 d_ncylinders; /* # of data cylinders per device */
559 __le32 d_ntracks; /* # of tracks per cylinder */
560 __le32 d_nsectors; /* # of data sectors per track */
561 __le32 d_secsize; /* # of bytes per sector */
562 __le32 d_part_start; /* # of first sector of this partition */
563 __le32 d_unknown1[12]; /* ? */
564 __le32 d_alt_tbl; /* byte offset of alternate table */
565 __le32 d_alt_len; /* byte length of alternate table */
566 __le32 d_phys_cyl; /* # of physical cylinders per device */
567 __le32 d_phys_trk; /* # of physical tracks per cylinder */
568 __le32 d_phys_sec; /* # of physical sectors per track */
569 __le32 d_phys_bytes; /* # of physical bytes per sector */
570 __le32 d_unknown2; /* ? */
571 __le32 d_unknown3; /* ? */
572 __le32 d_pad[8]; /* pad */
573
574 struct unixware_vtoc {
575 __le32 v_magic; /* the magic number */
576 __le32 v_version; /* version number */
577 char v_name[8]; /* volume name */
578 __le16 v_nslices; /* # of slices */
579 __le16 v_unknown1; /* ? */
580 __le32 v_reserved[10]; /* reserved */
581 struct unixware_slice
582 v_slice[UNIXWARE_NUMSLICE]; /* slice headers */
583 } vtoc;
584
585 }; /* 408 */
586
587 #endif /* CONFIG_UNIXWARE_DISKLABEL */
588
589 #ifdef CONFIG_MINIX_SUBPARTITION
590 # define MINIX_NR_SUBPARTITIONS 4
591 #endif /* CONFIG_MINIX_SUBPARTITION */
592
593 #define ADDPART_FLAG_NONE 0
594 #define ADDPART_FLAG_RAID 1
595 #define ADDPART_FLAG_WHOLEDISK 2
596
597 extern int blk_alloc_devt(struct hd_struct *part, dev_t *devt);
598 extern void blk_free_devt(dev_t devt);
599 extern dev_t blk_lookup_devt(const char *name, int partno);
600 extern char *disk_name (struct gendisk *hd, int partno, char *buf);
601
602 extern int disk_expand_part_tbl(struct gendisk *disk, int target);
603 extern int rescan_partitions(struct gendisk *disk, struct block_device *bdev);
604 extern int invalidate_partitions(struct gendisk *disk, struct block_device *bdev);
605 extern struct hd_struct * __must_check add_partition(struct gendisk *disk,
606 int partno, sector_t start,
607 sector_t len, int flags,
608 struct partition_meta_info
609 *info);
610 extern void __delete_partition(struct percpu_ref *);
611 extern void delete_partition(struct gendisk *, int);
612 extern void printk_all_partitions(void);
613
614 extern struct gendisk *__alloc_disk_node(int minors, int node_id);
615 extern struct kobject *get_disk_and_module(struct gendisk *disk);
616 extern void put_disk(struct gendisk *disk);
617 extern void put_disk_and_module(struct gendisk *disk);
618 extern void blk_register_region(dev_t devt, unsigned long range,
619 struct module *module,
620 struct kobject *(*probe)(dev_t, int *, void *),
621 int (*lock)(dev_t, void *),
622 void *data);
623 extern void blk_unregister_region(dev_t devt, unsigned long range);
624
625 extern ssize_t part_size_show(struct device *dev,
626 struct device_attribute *attr, char *buf);
627 extern ssize_t part_stat_show(struct device *dev,
628 struct device_attribute *attr, char *buf);
629 extern ssize_t part_inflight_show(struct device *dev,
630 struct device_attribute *attr, char *buf);
631 #ifdef CONFIG_FAIL_MAKE_REQUEST
632 extern ssize_t part_fail_show(struct device *dev,
633 struct device_attribute *attr, char *buf);
634 extern ssize_t part_fail_store(struct device *dev,
635 struct device_attribute *attr,
636 const char *buf, size_t count);
637 #endif /* CONFIG_FAIL_MAKE_REQUEST */
638
639 #define alloc_disk_node(minors, node_id) \
640 ({ \
641 static struct lock_class_key __key; \
642 const char *__name; \
643 struct gendisk *__disk; \
644 \
645 __name = "(gendisk_completion)"#minors"("#node_id")"; \
646 \
647 __disk = __alloc_disk_node(minors, node_id); \
648 \
649 if (__disk) \
650 lockdep_init_map(&__disk->lockdep_map, __name, &__key, 0); \
651 \
652 __disk; \
653 })
654
655 #define alloc_disk(minors) alloc_disk_node(minors, NUMA_NO_NODE)
656
hd_ref_init(struct hd_struct * part)657 static inline int hd_ref_init(struct hd_struct *part)
658 {
659 if (percpu_ref_init(&part->ref, __delete_partition, 0,
660 GFP_KERNEL))
661 return -ENOMEM;
662 return 0;
663 }
664
hd_struct_get(struct hd_struct * part)665 static inline void hd_struct_get(struct hd_struct *part)
666 {
667 percpu_ref_get(&part->ref);
668 }
669
hd_struct_try_get(struct hd_struct * part)670 static inline int hd_struct_try_get(struct hd_struct *part)
671 {
672 return percpu_ref_tryget_live(&part->ref);
673 }
674
hd_struct_put(struct hd_struct * part)675 static inline void hd_struct_put(struct hd_struct *part)
676 {
677 percpu_ref_put(&part->ref);
678 }
679
hd_struct_kill(struct hd_struct * part)680 static inline void hd_struct_kill(struct hd_struct *part)
681 {
682 percpu_ref_kill(&part->ref);
683 }
684
hd_free_part(struct hd_struct * part)685 static inline void hd_free_part(struct hd_struct *part)
686 {
687 free_part_stats(part);
688 free_part_info(part);
689 percpu_ref_exit(&part->ref);
690 }
691
692 /*
693 * Any access of part->nr_sects which is not protected by partition
694 * bd_mutex or gendisk bdev bd_mutex, should be done using this
695 * accessor function.
696 *
697 * Code written along the lines of i_size_read() and i_size_write().
698 * CONFIG_PREEMPT case optimizes the case of UP kernel with preemption
699 * on.
700 */
part_nr_sects_read(struct hd_struct * part)701 static inline sector_t part_nr_sects_read(struct hd_struct *part)
702 {
703 #if BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_SMP)
704 sector_t nr_sects;
705 unsigned seq;
706 do {
707 seq = read_seqcount_begin(&part->nr_sects_seq);
708 nr_sects = part->nr_sects;
709 } while (read_seqcount_retry(&part->nr_sects_seq, seq));
710 return nr_sects;
711 #elif BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_PREEMPT)
712 sector_t nr_sects;
713
714 preempt_disable();
715 nr_sects = part->nr_sects;
716 preempt_enable();
717 return nr_sects;
718 #else
719 return part->nr_sects;
720 #endif
721 }
722
723 /*
724 * Should be called with mutex lock held (typically bd_mutex) of partition
725 * to provide mutual exlusion among writers otherwise seqcount might be
726 * left in wrong state leaving the readers spinning infinitely.
727 */
part_nr_sects_write(struct hd_struct * part,sector_t size)728 static inline void part_nr_sects_write(struct hd_struct *part, sector_t size)
729 {
730 #if BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_SMP)
731 write_seqcount_begin(&part->nr_sects_seq);
732 part->nr_sects = size;
733 write_seqcount_end(&part->nr_sects_seq);
734 #elif BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_PREEMPT)
735 preempt_disable();
736 part->nr_sects = size;
737 preempt_enable();
738 #else
739 part->nr_sects = size;
740 #endif
741 }
742
743 #if defined(CONFIG_BLK_DEV_INTEGRITY)
744 extern void blk_integrity_add(struct gendisk *);
745 extern void blk_integrity_del(struct gendisk *);
746 #else /* CONFIG_BLK_DEV_INTEGRITY */
blk_integrity_add(struct gendisk * disk)747 static inline void blk_integrity_add(struct gendisk *disk) { }
blk_integrity_del(struct gendisk * disk)748 static inline void blk_integrity_del(struct gendisk *disk) { }
749 #endif /* CONFIG_BLK_DEV_INTEGRITY */
750
751 #else /* CONFIG_BLOCK */
752
printk_all_partitions(void)753 static inline void printk_all_partitions(void) { }
754
blk_lookup_devt(const char * name,int partno)755 static inline dev_t blk_lookup_devt(const char *name, int partno)
756 {
757 dev_t devt = MKDEV(0, 0);
758 return devt;
759 }
760 #endif /* CONFIG_BLOCK */
761
762 #endif /* _LINUX_GENHD_H */
763
