5 * genhd.h Copyright (C) 1992 Drew Eckhardt
6 * Generic hard disk header file by
12 #include <linux/types.h>
13 #include <linux/kdev_t.h>
14 #include <linux/rcupdate.h>
15 #include <linux/slab.h>
16 #include <linux/percpu-refcount.h>
17 #include <linux/uuid.h>
21 #define dev_to_disk(device) container_of((device), struct gendisk, part0.__dev)
22 #define dev_to_part(device) container_of((device), struct hd_struct, __dev)
23 #define disk_to_dev(disk) (&(disk)->part0.__dev)
24 #define part_to_dev(part) (&((part)->__dev))
26 extern struct device_type part_type
;
27 extern struct kobject
*block_depr
;
28 extern struct class block_class
;
31 /* These three have identical behaviour; use the second one if DOS FDISK gets
32 confused about extended/logical partitions starting past cylinder 1023. */
33 DOS_EXTENDED_PARTITION
= 5,
34 LINUX_EXTENDED_PARTITION
= 0x85,
35 WIN98_EXTENDED_PARTITION
= 0x0f,
37 SUN_WHOLE_DISK
= DOS_EXTENDED_PARTITION
,
39 LINUX_SWAP_PARTITION
= 0x82,
40 LINUX_DATA_PARTITION
= 0x83,
41 LINUX_LVM_PARTITION
= 0x8e,
42 LINUX_RAID_PARTITION
= 0xfd, /* autodetect RAID partition */
44 SOLARIS_X86_PARTITION
= LINUX_SWAP_PARTITION
,
45 NEW_SOLARIS_X86_PARTITION
= 0xbf,
47 DM6_AUX1PARTITION
= 0x51, /* no DDO: use xlated geom */
48 DM6_AUX3PARTITION
= 0x53, /* no DDO: use xlated geom */
49 DM6_PARTITION
= 0x54, /* has DDO: use xlated geom & offset */
50 EZD_PARTITION
= 0x55, /* EZ-DRIVE */
52 FREEBSD_PARTITION
= 0xa5, /* FreeBSD Partition ID */
53 OPENBSD_PARTITION
= 0xa6, /* OpenBSD Partition ID */
54 NETBSD_PARTITION
= 0xa9, /* NetBSD Partition ID */
55 BSDI_PARTITION
= 0xb7, /* BSDI Partition ID */
56 MINIX_PARTITION
= 0x81, /* Minix Partition ID */
57 UNIXWARE_PARTITION
= 0x63, /* Same as GNU_HURD and SCO Unix */
60 #define DISK_MAX_PARTS 256
61 #define DISK_NAME_LEN 32
63 #include <linux/major.h>
64 #include <linux/device.h>
65 #include <linux/smp.h>
66 #include <linux/string.h>
68 #include <linux/workqueue.h>
71 unsigned char boot_ind
; /* 0x80 - active */
72 unsigned char head
; /* starting head */
73 unsigned char sector
; /* starting sector */
74 unsigned char cyl
; /* starting cylinder */
75 unsigned char sys_ind
; /* What partition type */
76 unsigned char end_head
; /* end head */
77 unsigned char end_sector
; /* end sector */
78 unsigned char end_cyl
; /* end cylinder */
79 __le32 start_sect
; /* starting sector counting from 0 */
80 __le32 nr_sects
; /* nr of sectors in partition */
81 } __attribute__((packed
));
84 unsigned long sectors
[2]; /* READs and WRITEs */
86 unsigned long merges
[2];
87 unsigned long ticks
[2];
88 unsigned long io_ticks
;
89 unsigned long time_in_queue
;
92 #define PARTITION_META_INFO_VOLNAMELTH 64
94 * Enough for the string representation of any kind of UUID plus NULL.
95 * EFI UUID is 36 characters. MSDOS UUID is 11 characters.
97 #define PARTITION_META_INFO_UUIDLTH (UUID_STRING_LEN + 1)
99 struct partition_meta_info
{
100 char uuid
[PARTITION_META_INFO_UUIDLTH
];
101 u8 volname
[PARTITION_META_INFO_VOLNAMELTH
];
107 * nr_sects is protected by sequence counter. One might extend a
108 * partition while IO is happening to it and update of nr_sects
109 * can be non-atomic on 32bit machines with 64bit sector_t.
112 seqcount_t nr_sects_seq
;
113 sector_t alignment_offset
;
114 unsigned int discard_alignment
;
116 struct kobject
*holder_dir
;
118 struct partition_meta_info
*info
;
119 #ifdef CONFIG_FAIL_MAKE_REQUEST
123 atomic_t in_flight
[2];
125 struct disk_stats __percpu
*dkstats
;
127 struct disk_stats dkstats
;
129 struct percpu_ref ref
;
130 struct rcu_head rcu_head
;
133 #define GENHD_FL_REMOVABLE 1
135 #define GENHD_FL_MEDIA_CHANGE_NOTIFY 4
136 #define GENHD_FL_CD 8
137 #define GENHD_FL_UP 16
138 #define GENHD_FL_SUPPRESS_PARTITION_INFO 32
139 #define GENHD_FL_EXT_DEVT 64 /* allow extended devt */
140 #define GENHD_FL_NATIVE_CAPACITY 128
141 #define GENHD_FL_BLOCK_EVENTS_ON_EXCL_WRITE 256
142 #define GENHD_FL_NO_PART_SCAN 512
145 DISK_EVENT_MEDIA_CHANGE
= 1 << 0, /* media changed */
146 DISK_EVENT_EJECT_REQUEST
= 1 << 1, /* eject requested */
149 struct disk_part_tbl
{
150 struct rcu_head rcu_head
;
152 struct hd_struct __rcu
*last_lookup
;
153 struct hd_struct __rcu
*part
[];
159 #if defined(CONFIG_BLK_DEV_INTEGRITY)
161 struct blk_integrity
{
162 const struct blk_integrity_profile
*profile
;
164 unsigned char tuple_size
;
165 unsigned char interval_exp
;
166 unsigned char tag_size
;
169 #endif /* CONFIG_BLK_DEV_INTEGRITY */
172 /* major, first_minor and minors are input parameters only,
173 * don't use directly. Use disk_devt() and disk_max_parts().
175 int major
; /* major number of driver */
177 int minors
; /* maximum number of minors, =1 for
178 * disks that can't be partitioned. */
180 char disk_name
[DISK_NAME_LEN
]; /* name of major driver */
181 char *(*devnode
)(struct gendisk
*gd
, umode_t
*mode
);
183 unsigned int events
; /* supported events */
184 unsigned int async_events
; /* async events, subset of all */
186 /* Array of pointers to partitions indexed by partno.
187 * Protected with matching bdev lock but stat and other
188 * non-critical accesses use RCU. Always access through
191 struct disk_part_tbl __rcu
*part_tbl
;
192 struct hd_struct part0
;
194 const struct block_device_operations
*fops
;
195 struct request_queue
*queue
;
199 struct kobject
*slave_dir
;
201 struct timer_rand_state
*random
;
202 atomic_t sync_io
; /* RAID */
203 struct disk_events
*ev
;
204 #ifdef CONFIG_BLK_DEV_INTEGRITY
205 struct kobject integrity_kobj
;
206 #endif /* CONFIG_BLK_DEV_INTEGRITY */
208 struct badblocks
*bb
;
211 static inline struct gendisk
*part_to_disk(struct hd_struct
*part
)
215 return dev_to_disk(part_to_dev(part
)->parent
);
217 return dev_to_disk(part_to_dev(part
));
222 static inline int blk_part_pack_uuid(const u8
*uuid_str
, u8
*to
)
224 uuid_be_to_bin(uuid_str
, (uuid_be
*)to
);
228 static inline int disk_max_parts(struct gendisk
*disk
)
230 if (disk
->flags
& GENHD_FL_EXT_DEVT
)
231 return DISK_MAX_PARTS
;
235 static inline bool disk_part_scan_enabled(struct gendisk
*disk
)
237 return disk_max_parts(disk
) > 1 &&
238 !(disk
->flags
& GENHD_FL_NO_PART_SCAN
);
241 static inline dev_t
disk_devt(struct gendisk
*disk
)
243 return disk_to_dev(disk
)->devt
;
246 static inline dev_t
part_devt(struct hd_struct
*part
)
248 return part_to_dev(part
)->devt
;
251 extern struct hd_struct
*disk_get_part(struct gendisk
*disk
, int partno
);
253 static inline void disk_put_part(struct hd_struct
*part
)
256 put_device(part_to_dev(part
));
260 * Smarter partition iterator without context limits.
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 */
267 struct disk_part_iter
{
268 struct gendisk
*disk
;
269 struct hd_struct
*part
;
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
);
279 extern struct hd_struct
*disk_map_sector_rcu(struct gendisk
*disk
,
283 * Macros to operate on percpu disk statistics:
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().
289 * part_stat_read() can be called at any time.
291 * part_stat_{add|set_all}() and {init|free}_part_stats are for
295 #define part_stat_lock() ({ rcu_read_lock(); get_cpu(); })
296 #define part_stat_unlock() do { put_cpu(); rcu_read_unlock(); } while (0)
298 #define __part_stat_add(cpu, part, field, addnd) \
299 (per_cpu_ptr((part)->dkstats, (cpu))->field += (addnd))
301 #define part_stat_read(part, field) \
303 typeof((part)->dkstats->field) res = 0; \
305 for_each_possible_cpu(_cpu) \
306 res += per_cpu_ptr((part)->dkstats, _cpu)->field; \
310 static inline void part_stat_set_all(struct hd_struct
*part
, int value
)
314 for_each_possible_cpu(i
)
315 memset(per_cpu_ptr(part
->dkstats
, i
), value
,
316 sizeof(struct disk_stats
));
319 static inline int init_part_stats(struct hd_struct
*part
)
321 part
->dkstats
= alloc_percpu(struct disk_stats
);
327 static inline void free_part_stats(struct hd_struct
*part
)
329 free_percpu(part
->dkstats
);
332 #else /* !CONFIG_SMP */
333 #define part_stat_lock() ({ rcu_read_lock(); 0; })
334 #define part_stat_unlock() rcu_read_unlock()
336 #define __part_stat_add(cpu, part, field, addnd) \
337 ((part)->dkstats.field += addnd)
339 #define part_stat_read(part, field) ((part)->dkstats.field)
341 static inline void part_stat_set_all(struct hd_struct
*part
, int value
)
343 memset(&part
->dkstats
, value
, sizeof(struct disk_stats
));
346 static inline int init_part_stats(struct hd_struct
*part
)
351 static inline void free_part_stats(struct hd_struct
*part
)
355 #endif /* CONFIG_SMP */
357 #define part_stat_add(cpu, part, field, addnd) do { \
358 __part_stat_add((cpu), (part), field, addnd); \
359 if ((part)->partno) \
360 __part_stat_add((cpu), &part_to_disk((part))->part0, \
364 #define part_stat_dec(cpu, gendiskp, field) \
365 part_stat_add(cpu, gendiskp, field, -1)
366 #define part_stat_inc(cpu, gendiskp, field) \
367 part_stat_add(cpu, gendiskp, field, 1)
368 #define part_stat_sub(cpu, gendiskp, field, subnd) \
369 part_stat_add(cpu, gendiskp, field, -subnd)
371 static inline void part_inc_in_flight(struct hd_struct
*part
, int rw
)
373 atomic_inc(&part
->in_flight
[rw
]);
375 atomic_inc(&part_to_disk(part
)->part0
.in_flight
[rw
]);
378 static inline void part_dec_in_flight(struct hd_struct
*part
, int rw
)
380 atomic_dec(&part
->in_flight
[rw
]);
382 atomic_dec(&part_to_disk(part
)->part0
.in_flight
[rw
]);
385 static inline int part_in_flight(struct hd_struct
*part
)
387 return atomic_read(&part
->in_flight
[0]) + atomic_read(&part
->in_flight
[1]);
390 static inline struct partition_meta_info
*alloc_part_info(struct gendisk
*disk
)
393 return kzalloc_node(sizeof(struct partition_meta_info
),
394 GFP_KERNEL
, disk
->node_id
);
395 return kzalloc(sizeof(struct partition_meta_info
), GFP_KERNEL
);
398 static inline void free_part_info(struct hd_struct
*part
)
403 /* block/blk-core.c */
404 extern void part_round_stats(int cpu
, struct hd_struct
*part
);
407 extern void device_add_disk(struct device
*parent
, struct gendisk
*disk
);
408 static inline void add_disk(struct gendisk
*disk
)
410 device_add_disk(NULL
, disk
);
413 extern void del_gendisk(struct gendisk
*gp
);
414 extern struct gendisk
*get_gendisk(dev_t dev
, int *partno
);
415 extern struct block_device
*bdget_disk(struct gendisk
*disk
, int partno
);
417 extern void set_device_ro(struct block_device
*bdev
, int flag
);
418 extern void set_disk_ro(struct gendisk
*disk
, int flag
);
420 static inline int get_disk_ro(struct gendisk
*disk
)
422 return disk
->part0
.policy
;
425 extern void disk_block_events(struct gendisk
*disk
);
426 extern void disk_unblock_events(struct gendisk
*disk
);
427 extern void disk_flush_events(struct gendisk
*disk
, unsigned int mask
);
428 extern unsigned int disk_clear_events(struct gendisk
*disk
, unsigned int mask
);
430 /* drivers/char/random.c */
431 extern void add_disk_randomness(struct gendisk
*disk
) __latent_entropy
;
432 extern void rand_initialize_disk(struct gendisk
*disk
);
434 static inline sector_t
get_start_sect(struct block_device
*bdev
)
436 return bdev
->bd_part
->start_sect
;
438 static inline sector_t
get_capacity(struct gendisk
*disk
)
440 return disk
->part0
.nr_sects
;
442 static inline void set_capacity(struct gendisk
*disk
, sector_t size
)
444 disk
->part0
.nr_sects
= size
;
447 #ifdef CONFIG_SOLARIS_X86_PARTITION
449 #define SOLARIS_X86_NUMSLICE 16
450 #define SOLARIS_X86_VTOC_SANE (0x600DDEEEUL)
452 struct solaris_x86_slice
{
453 __le16 s_tag
; /* ID tag of partition */
454 __le16 s_flag
; /* permission flags */
455 __le32 s_start
; /* start sector no of partition */
456 __le32 s_size
; /* # of blocks in partition */
459 struct solaris_x86_vtoc
{
460 unsigned int v_bootinfo
[3]; /* info needed by mboot (unsupported) */
461 __le32 v_sanity
; /* to verify vtoc sanity */
462 __le32 v_version
; /* layout version */
463 char v_volume
[8]; /* volume name */
464 __le16 v_sectorsz
; /* sector size in bytes */
465 __le16 v_nparts
; /* number of partitions */
466 unsigned int v_reserved
[10]; /* free space */
467 struct solaris_x86_slice
468 v_slice
[SOLARIS_X86_NUMSLICE
]; /* slice headers */
469 unsigned int timestamp
[SOLARIS_X86_NUMSLICE
]; /* timestamp (unsupported) */
470 char v_asciilabel
[128]; /* for compatibility */
473 #endif /* CONFIG_SOLARIS_X86_PARTITION */
475 #ifdef CONFIG_BSD_DISKLABEL
477 * BSD disklabel support by Yossi Gottlieb <yogo@math.tau.ac.il>
478 * updated by Marc Espie <Marc.Espie@openbsd.org>
481 /* check against BSD src/sys/sys/disklabel.h for consistency */
483 #define BSD_DISKMAGIC (0x82564557UL) /* The disk magic number */
484 #define BSD_MAXPARTITIONS 16
485 #define OPENBSD_MAXPARTITIONS 16
486 #define BSD_FS_UNUSED 0 /* disklabel unused partition entry ID */
487 struct bsd_disklabel
{
488 __le32 d_magic
; /* the magic number */
489 __s16 d_type
; /* drive type */
490 __s16 d_subtype
; /* controller/d_type specific */
491 char d_typename
[16]; /* type name, e.g. "eagle" */
492 char d_packname
[16]; /* pack identifier */
493 __u32 d_secsize
; /* # of bytes per sector */
494 __u32 d_nsectors
; /* # of data sectors per track */
495 __u32 d_ntracks
; /* # of tracks per cylinder */
496 __u32 d_ncylinders
; /* # of data cylinders per unit */
497 __u32 d_secpercyl
; /* # of data sectors per cylinder */
498 __u32 d_secperunit
; /* # of data sectors per unit */
499 __u16 d_sparespertrack
; /* # of spare sectors per track */
500 __u16 d_sparespercyl
; /* # of spare sectors per cylinder */
501 __u32 d_acylinders
; /* # of alt. cylinders per unit */
502 __u16 d_rpm
; /* rotational speed */
503 __u16 d_interleave
; /* hardware sector interleave */
504 __u16 d_trackskew
; /* sector 0 skew, per track */
505 __u16 d_cylskew
; /* sector 0 skew, per cylinder */
506 __u32 d_headswitch
; /* head switch time, usec */
507 __u32 d_trkseek
; /* track-to-track seek, usec */
508 __u32 d_flags
; /* generic flags */
510 __u32 d_drivedata
[NDDATA
]; /* drive-type specific information */
512 __u32 d_spare
[NSPARE
]; /* reserved for future use */
513 __le32 d_magic2
; /* the magic number (again) */
514 __le16 d_checksum
; /* xor of data incl. partitions */
516 /* filesystem and partition information: */
517 __le16 d_npartitions
; /* number of partitions in following */
518 __le32 d_bbsize
; /* size of boot area at sn0, bytes */
519 __le32 d_sbsize
; /* max size of fs superblock, bytes */
520 struct bsd_partition
{ /* the partition table */
521 __le32 p_size
; /* number of sectors in partition */
522 __le32 p_offset
; /* starting sector */
523 __le32 p_fsize
; /* filesystem basic fragment size */
524 __u8 p_fstype
; /* filesystem type, see below */
525 __u8 p_frag
; /* filesystem fragments per block */
526 __le16 p_cpg
; /* filesystem cylinders per group */
527 } d_partitions
[BSD_MAXPARTITIONS
]; /* actually may be more */
530 #endif /* CONFIG_BSD_DISKLABEL */
532 #ifdef CONFIG_UNIXWARE_DISKLABEL
534 * Unixware slices support by Andrzej Krzysztofowicz <ankry@mif.pg.gda.pl>
535 * and Krzysztof G. Baranowski <kgb@knm.org.pl>
538 #define UNIXWARE_DISKMAGIC (0xCA5E600DUL) /* The disk magic number */
539 #define UNIXWARE_DISKMAGIC2 (0x600DDEEEUL) /* The slice table magic nr */
540 #define UNIXWARE_NUMSLICE 16
541 #define UNIXWARE_FS_UNUSED 0 /* Unused slice entry ID */
543 struct unixware_slice
{
544 __le16 s_label
; /* label */
545 __le16 s_flags
; /* permission flags */
546 __le32 start_sect
; /* starting sector */
547 __le32 nr_sects
; /* number of sectors in slice */
550 struct unixware_disklabel
{
551 __le32 d_type
; /* drive type */
552 __le32 d_magic
; /* the magic number */
553 __le32 d_version
; /* version number */
554 char d_serial
[12]; /* serial number of the device */
555 __le32 d_ncylinders
; /* # of data cylinders per device */
556 __le32 d_ntracks
; /* # of tracks per cylinder */
557 __le32 d_nsectors
; /* # of data sectors per track */
558 __le32 d_secsize
; /* # of bytes per sector */
559 __le32 d_part_start
; /* # of first sector of this partition */
560 __le32 d_unknown1
[12]; /* ? */
561 __le32 d_alt_tbl
; /* byte offset of alternate table */
562 __le32 d_alt_len
; /* byte length of alternate table */
563 __le32 d_phys_cyl
; /* # of physical cylinders per device */
564 __le32 d_phys_trk
; /* # of physical tracks per cylinder */
565 __le32 d_phys_sec
; /* # of physical sectors per track */
566 __le32 d_phys_bytes
; /* # of physical bytes per sector */
567 __le32 d_unknown2
; /* ? */
568 __le32 d_unknown3
; /* ? */
569 __le32 d_pad
[8]; /* pad */
571 struct unixware_vtoc
{
572 __le32 v_magic
; /* the magic number */
573 __le32 v_version
; /* version number */
574 char v_name
[8]; /* volume name */
575 __le16 v_nslices
; /* # of slices */
576 __le16 v_unknown1
; /* ? */
577 __le32 v_reserved
[10]; /* reserved */
578 struct unixware_slice
579 v_slice
[UNIXWARE_NUMSLICE
]; /* slice headers */
584 #endif /* CONFIG_UNIXWARE_DISKLABEL */
586 #ifdef CONFIG_MINIX_SUBPARTITION
587 # define MINIX_NR_SUBPARTITIONS 4
588 #endif /* CONFIG_MINIX_SUBPARTITION */
590 #define ADDPART_FLAG_NONE 0
591 #define ADDPART_FLAG_RAID 1
592 #define ADDPART_FLAG_WHOLEDISK 2
594 extern int blk_alloc_devt(struct hd_struct
*part
, dev_t
*devt
);
595 extern void blk_free_devt(dev_t devt
);
596 extern dev_t
blk_lookup_devt(const char *name
, int partno
);
597 extern char *disk_name (struct gendisk
*hd
, int partno
, char *buf
);
599 extern int disk_expand_part_tbl(struct gendisk
*disk
, int target
);
600 extern int rescan_partitions(struct gendisk
*disk
, struct block_device
*bdev
);
601 extern int invalidate_partitions(struct gendisk
*disk
, struct block_device
*bdev
);
602 extern struct hd_struct
* __must_check
add_partition(struct gendisk
*disk
,
603 int partno
, sector_t start
,
604 sector_t len
, int flags
,
605 struct partition_meta_info
607 extern void __delete_partition(struct percpu_ref
*);
608 extern void delete_partition(struct gendisk
*, int);
609 extern void printk_all_partitions(void);
611 extern struct gendisk
*alloc_disk_node(int minors
, int node_id
);
612 extern struct gendisk
*alloc_disk(int minors
);
613 extern struct kobject
*get_disk(struct gendisk
*disk
);
614 extern void put_disk(struct gendisk
*disk
);
615 extern void blk_register_region(dev_t devt
, unsigned long range
,
616 struct module
*module
,
617 struct kobject
*(*probe
)(dev_t
, int *, void *),
618 int (*lock
)(dev_t
, void *),
620 extern void blk_unregister_region(dev_t devt
, unsigned long range
);
622 extern ssize_t
part_size_show(struct device
*dev
,
623 struct device_attribute
*attr
, char *buf
);
624 extern ssize_t
part_stat_show(struct device
*dev
,
625 struct device_attribute
*attr
, char *buf
);
626 extern ssize_t
part_inflight_show(struct device
*dev
,
627 struct device_attribute
*attr
, char *buf
);
628 #ifdef CONFIG_FAIL_MAKE_REQUEST
629 extern ssize_t
part_fail_show(struct device
*dev
,
630 struct device_attribute
*attr
, char *buf
);
631 extern ssize_t
part_fail_store(struct device
*dev
,
632 struct device_attribute
*attr
,
633 const char *buf
, size_t count
);
634 #endif /* CONFIG_FAIL_MAKE_REQUEST */
636 static inline int hd_ref_init(struct hd_struct
*part
)
638 if (percpu_ref_init(&part
->ref
, __delete_partition
, 0,
644 static inline void hd_struct_get(struct hd_struct
*part
)
646 percpu_ref_get(&part
->ref
);
649 static inline int hd_struct_try_get(struct hd_struct
*part
)
651 return percpu_ref_tryget_live(&part
->ref
);
654 static inline void hd_struct_put(struct hd_struct
*part
)
656 percpu_ref_put(&part
->ref
);
659 static inline void hd_struct_kill(struct hd_struct
*part
)
661 percpu_ref_kill(&part
->ref
);
664 static inline void hd_free_part(struct hd_struct
*part
)
666 free_part_stats(part
);
667 free_part_info(part
);
668 percpu_ref_exit(&part
->ref
);
672 * Any access of part->nr_sects which is not protected by partition
673 * bd_mutex or gendisk bdev bd_mutex, should be done using this
676 * Code written along the lines of i_size_read() and i_size_write().
677 * CONFIG_PREEMPT case optimizes the case of UP kernel with preemption
680 static inline sector_t
part_nr_sects_read(struct hd_struct
*part
)
682 #if BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_SMP)
686 seq
= read_seqcount_begin(&part
->nr_sects_seq
);
687 nr_sects
= part
->nr_sects
;
688 } while (read_seqcount_retry(&part
->nr_sects_seq
, seq
));
690 #elif BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_PREEMPT)
694 nr_sects
= part
->nr_sects
;
698 return part
->nr_sects
;
703 * Should be called with mutex lock held (typically bd_mutex) of partition
704 * to provide mutual exlusion among writers otherwise seqcount might be
705 * left in wrong state leaving the readers spinning infinitely.
707 static inline void part_nr_sects_write(struct hd_struct
*part
, sector_t size
)
709 #if BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_SMP)
710 write_seqcount_begin(&part
->nr_sects_seq
);
711 part
->nr_sects
= size
;
712 write_seqcount_end(&part
->nr_sects_seq
);
713 #elif BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_PREEMPT)
715 part
->nr_sects
= size
;
718 part
->nr_sects
= size
;
722 #if defined(CONFIG_BLK_DEV_INTEGRITY)
723 extern void blk_integrity_add(struct gendisk
*);
724 extern void blk_integrity_del(struct gendisk
*);
725 #else /* CONFIG_BLK_DEV_INTEGRITY */
726 static inline void blk_integrity_add(struct gendisk
*disk
) { }
727 static inline void blk_integrity_del(struct gendisk
*disk
) { }
728 #endif /* CONFIG_BLK_DEV_INTEGRITY */
730 #else /* CONFIG_BLOCK */
732 static inline void printk_all_partitions(void) { }
734 static inline dev_t
blk_lookup_devt(const char *name
, int partno
)
736 dev_t devt
= MKDEV(0, 0);
740 static inline int blk_part_pack_uuid(const u8
*uuid_str
, u8
*to
)
744 #endif /* CONFIG_BLOCK */
746 #endif /* _LINUX_GENHD_H */