1 /* SPDX-License-Identifier: GPL-2.0 */
6 * genhd.h Copyright (C) 1992 Drew Eckhardt
7 * Generic hard disk header file by
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>
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))
27 extern struct device_type part_type
;
28 extern struct kobject
*block_depr
;
29 extern struct class block_class
;
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,
38 SUN_WHOLE_DISK
= DOS_EXTENDED_PARTITION
,
40 LINUX_SWAP_PARTITION
= 0x82,
41 LINUX_DATA_PARTITION
= 0x83,
42 LINUX_LVM_PARTITION
= 0x8e,
43 LINUX_RAID_PARTITION
= 0xfd, /* autodetect RAID partition */
45 SOLARIS_X86_PARTITION
= LINUX_SWAP_PARTITION
,
46 NEW_SOLARIS_X86_PARTITION
= 0xbf,
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 */
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 */
61 #define DISK_MAX_PARTS 256
62 #define DISK_NAME_LEN 32
64 #include <linux/major.h>
65 #include <linux/device.h>
66 #include <linux/smp.h>
67 #include <linux/string.h>
69 #include <linux/workqueue.h>
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
));
85 unsigned long sectors
[2]; /* READs and WRITEs */
87 unsigned long merges
[2];
88 unsigned long ticks
[2];
89 unsigned long io_ticks
;
90 unsigned long time_in_queue
;
93 #define PARTITION_META_INFO_VOLNAMELTH 64
95 * Enough for the string representation of any kind of UUID plus NULL.
96 * EFI UUID is 36 characters. MSDOS UUID is 11 characters.
98 #define PARTITION_META_INFO_UUIDLTH (UUID_STRING_LEN + 1)
100 struct partition_meta_info
{
101 char uuid
[PARTITION_META_INFO_UUIDLTH
];
102 u8 volname
[PARTITION_META_INFO_VOLNAMELTH
];
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.
113 seqcount_t nr_sects_seq
;
114 sector_t alignment_offset
;
115 unsigned int discard_alignment
;
117 struct kobject
*holder_dir
;
119 struct partition_meta_info
*info
;
120 #ifdef CONFIG_FAIL_MAKE_REQUEST
124 atomic_t in_flight
[2];
126 struct disk_stats __percpu
*dkstats
;
128 struct disk_stats dkstats
;
130 struct percpu_ref ref
;
131 struct rcu_head rcu_head
;
134 #define GENHD_FL_REMOVABLE 1
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
146 DISK_EVENT_MEDIA_CHANGE
= 1 << 0, /* media changed */
147 DISK_EVENT_EJECT_REQUEST
= 1 << 1, /* eject requested */
150 struct disk_part_tbl
{
151 struct rcu_head rcu_head
;
153 struct hd_struct __rcu
*last_lookup
;
154 struct hd_struct __rcu
*part
[];
160 #if defined(CONFIG_BLK_DEV_INTEGRITY)
162 struct blk_integrity
{
163 const struct blk_integrity_profile
*profile
;
165 unsigned char tuple_size
;
166 unsigned char interval_exp
;
167 unsigned char tag_size
;
170 #endif /* CONFIG_BLK_DEV_INTEGRITY */
173 /* major, first_minor and minors are input parameters only,
174 * don't use directly. Use disk_devt() and disk_max_parts().
176 int major
; /* major number of driver */
178 int minors
; /* maximum number of minors, =1 for
179 * disks that can't be partitioned. */
181 char disk_name
[DISK_NAME_LEN
]; /* name of major driver */
182 char *(*devnode
)(struct gendisk
*gd
, umode_t
*mode
);
184 unsigned int events
; /* supported events */
185 unsigned int async_events
; /* async events, subset of all */
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
192 struct disk_part_tbl __rcu
*part_tbl
;
193 struct hd_struct part0
;
195 const struct block_device_operations
*fops
;
196 struct request_queue
*queue
;
200 struct kobject
*slave_dir
;
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 */
209 struct badblocks
*bb
;
212 static inline struct gendisk
*part_to_disk(struct hd_struct
*part
)
216 return dev_to_disk(part_to_dev(part
)->parent
);
218 return dev_to_disk(part_to_dev(part
));
223 static inline int disk_max_parts(struct gendisk
*disk
)
225 if (disk
->flags
& GENHD_FL_EXT_DEVT
)
226 return DISK_MAX_PARTS
;
230 static inline bool disk_part_scan_enabled(struct gendisk
*disk
)
232 return disk_max_parts(disk
) > 1 &&
233 !(disk
->flags
& GENHD_FL_NO_PART_SCAN
);
236 static inline dev_t
disk_devt(struct gendisk
*disk
)
238 return disk_to_dev(disk
)->devt
;
241 static inline dev_t
part_devt(struct hd_struct
*part
)
243 return part_to_dev(part
)->devt
;
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
);
249 static inline void disk_put_part(struct hd_struct
*part
)
252 put_device(part_to_dev(part
));
256 * Smarter partition iterator without context limits.
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 */
263 struct disk_part_iter
{
264 struct gendisk
*disk
;
265 struct hd_struct
*part
;
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
);
275 extern struct hd_struct
*disk_map_sector_rcu(struct gendisk
*disk
,
279 * Macros to operate on percpu disk statistics:
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().
285 * part_stat_read() can be called at any time.
287 * part_stat_{add|set_all}() and {init|free}_part_stats are for
291 #define part_stat_lock() ({ rcu_read_lock(); get_cpu(); })
292 #define part_stat_unlock() do { put_cpu(); rcu_read_unlock(); } while (0)
294 #define __part_stat_add(cpu, part, field, addnd) \
295 (per_cpu_ptr((part)->dkstats, (cpu))->field += (addnd))
297 #define part_stat_read(part, field) \
299 typeof((part)->dkstats->field) res = 0; \
301 for_each_possible_cpu(_cpu) \
302 res += per_cpu_ptr((part)->dkstats, _cpu)->field; \
306 static inline void part_stat_set_all(struct hd_struct
*part
, int value
)
310 for_each_possible_cpu(i
)
311 memset(per_cpu_ptr(part
->dkstats
, i
), value
,
312 sizeof(struct disk_stats
));
315 static inline int init_part_stats(struct hd_struct
*part
)
317 part
->dkstats
= alloc_percpu(struct disk_stats
);
323 static inline void free_part_stats(struct hd_struct
*part
)
325 free_percpu(part
->dkstats
);
328 #else /* !CONFIG_SMP */
329 #define part_stat_lock() ({ rcu_read_lock(); 0; })
330 #define part_stat_unlock() rcu_read_unlock()
332 #define __part_stat_add(cpu, part, field, addnd) \
333 ((part)->dkstats.field += addnd)
335 #define part_stat_read(part, field) ((part)->dkstats.field)
337 static inline void part_stat_set_all(struct hd_struct
*part
, int value
)
339 memset(&part
->dkstats
, value
, sizeof(struct disk_stats
));
342 static inline int init_part_stats(struct hd_struct
*part
)
347 static inline void free_part_stats(struct hd_struct
*part
)
351 #endif /* CONFIG_SMP */
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, \
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)
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
,
373 void part_inc_in_flight(struct request_queue
*q
, struct hd_struct
*part
,
376 static inline struct partition_meta_info
*alloc_part_info(struct gendisk
*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
);
384 static inline void free_part_info(struct hd_struct
*part
)
389 /* block/blk-core.c */
390 extern void part_round_stats(struct request_queue
*q
, int cpu
, struct hd_struct
*part
);
393 extern void device_add_disk(struct device
*parent
, struct gendisk
*disk
);
394 static inline void add_disk(struct gendisk
*disk
)
396 device_add_disk(NULL
, disk
);
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
);
403 extern void set_device_ro(struct block_device
*bdev
, int flag
);
404 extern void set_disk_ro(struct gendisk
*disk
, int flag
);
406 static inline int get_disk_ro(struct gendisk
*disk
)
408 return disk
->part0
.policy
;
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
);
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
);
420 static inline sector_t
get_start_sect(struct block_device
*bdev
)
422 return bdev
->bd_part
->start_sect
;
424 static inline sector_t
get_capacity(struct gendisk
*disk
)
426 return disk
->part0
.nr_sects
;
428 static inline void set_capacity(struct gendisk
*disk
, sector_t size
)
430 disk
->part0
.nr_sects
= size
;
433 #ifdef CONFIG_SOLARIS_X86_PARTITION
435 #define SOLARIS_X86_NUMSLICE 16
436 #define SOLARIS_X86_VTOC_SANE (0x600DDEEEUL)
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 */
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 */
459 #endif /* CONFIG_SOLARIS_X86_PARTITION */
461 #ifdef CONFIG_BSD_DISKLABEL
463 * BSD disklabel support by Yossi Gottlieb <yogo@math.tau.ac.il>
464 * updated by Marc Espie <Marc.Espie@openbsd.org>
467 /* check against BSD src/sys/sys/disklabel.h for consistency */
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 */
496 __u32 d_drivedata
[NDDATA
]; /* drive-type specific information */
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 */
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 */
516 #endif /* CONFIG_BSD_DISKLABEL */
518 #ifdef CONFIG_UNIXWARE_DISKLABEL
520 * Unixware slices support by Andrzej Krzysztofowicz <ankry@mif.pg.gda.pl>
521 * and Krzysztof G. Baranowski <kgb@knm.org.pl>
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 */
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 */
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 */
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 */
570 #endif /* CONFIG_UNIXWARE_DISKLABEL */
572 #ifdef CONFIG_MINIX_SUBPARTITION
573 # define MINIX_NR_SUBPARTITIONS 4
574 #endif /* CONFIG_MINIX_SUBPARTITION */
576 #define ADDPART_FLAG_NONE 0
577 #define ADDPART_FLAG_RAID 1
578 #define ADDPART_FLAG_WHOLEDISK 2
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
);
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
593 extern void __delete_partition(struct percpu_ref
*);
594 extern void delete_partition(struct gendisk
*, int);
595 extern void printk_all_partitions(void);
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 *),
606 extern void blk_unregister_region(dev_t devt
, unsigned long range
);
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 */
622 static inline int hd_ref_init(struct hd_struct
*part
)
624 if (percpu_ref_init(&part
->ref
, __delete_partition
, 0,
630 static inline void hd_struct_get(struct hd_struct
*part
)
632 percpu_ref_get(&part
->ref
);
635 static inline int hd_struct_try_get(struct hd_struct
*part
)
637 return percpu_ref_tryget_live(&part
->ref
);
640 static inline void hd_struct_put(struct hd_struct
*part
)
642 percpu_ref_put(&part
->ref
);
645 static inline void hd_struct_kill(struct hd_struct
*part
)
647 percpu_ref_kill(&part
->ref
);
650 static inline void hd_free_part(struct hd_struct
*part
)
652 free_part_stats(part
);
653 free_part_info(part
);
654 percpu_ref_exit(&part
->ref
);
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
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
666 static inline sector_t
part_nr_sects_read(struct hd_struct
*part
)
668 #if BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_SMP)
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
));
676 #elif BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_PREEMPT)
680 nr_sects
= part
->nr_sects
;
684 return part
->nr_sects
;
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.
693 static inline void part_nr_sects_write(struct hd_struct
*part
, sector_t size
)
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)
701 part
->nr_sects
= size
;
704 part
->nr_sects
= size
;
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 */
712 static inline void blk_integrity_add(struct gendisk
*disk
) { }
713 static inline void blk_integrity_del(struct gendisk
*disk
) { }
714 #endif /* CONFIG_BLK_DEV_INTEGRITY */
716 #else /* CONFIG_BLOCK */
718 static inline void printk_all_partitions(void) { }
720 static inline dev_t
blk_lookup_devt(const char *name
, int partno
)
722 dev_t devt
= MKDEV(0, 0);
725 #endif /* CONFIG_BLOCK */
727 #endif /* _LINUX_GENHD_H */