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>
19 #include <linux/blk_types.h>
20 #include <asm/local.h>
24 #define dev_to_disk(device) container_of((device), struct gendisk, part0.__dev)
25 #define dev_to_part(device) container_of((device), struct hd_struct, __dev)
26 #define disk_to_dev(disk) (&(disk)->part0.__dev)
27 #define part_to_dev(part) (&((part)->__dev))
29 extern struct device_type part_type;
30 extern struct kobject *block_depr;
31 extern struct class block_class;
34 /* These three have identical behaviour; use the second one if DOS FDISK gets
35 confused about extended/logical partitions starting past cylinder 1023. */
36 DOS_EXTENDED_PARTITION = 5,
37 LINUX_EXTENDED_PARTITION = 0x85,
38 WIN98_EXTENDED_PARTITION = 0x0f,
40 SUN_WHOLE_DISK = DOS_EXTENDED_PARTITION,
42 LINUX_SWAP_PARTITION = 0x82,
43 LINUX_DATA_PARTITION = 0x83,
44 LINUX_LVM_PARTITION = 0x8e,
45 LINUX_RAID_PARTITION = 0xfd, /* autodetect RAID partition */
47 SOLARIS_X86_PARTITION = LINUX_SWAP_PARTITION,
48 NEW_SOLARIS_X86_PARTITION = 0xbf,
50 DM6_AUX1PARTITION = 0x51, /* no DDO: use xlated geom */
51 DM6_AUX3PARTITION = 0x53, /* no DDO: use xlated geom */
52 DM6_PARTITION = 0x54, /* has DDO: use xlated geom & offset */
53 EZD_PARTITION = 0x55, /* EZ-DRIVE */
55 FREEBSD_PARTITION = 0xa5, /* FreeBSD Partition ID */
56 OPENBSD_PARTITION = 0xa6, /* OpenBSD Partition ID */
57 NETBSD_PARTITION = 0xa9, /* NetBSD Partition ID */
58 BSDI_PARTITION = 0xb7, /* BSDI Partition ID */
59 MINIX_PARTITION = 0x81, /* Minix Partition ID */
60 UNIXWARE_PARTITION = 0x63, /* Same as GNU_HURD and SCO Unix */
63 #define DISK_MAX_PARTS 256
64 #define DISK_NAME_LEN 32
66 #include <linux/major.h>
67 #include <linux/device.h>
68 #include <linux/smp.h>
69 #include <linux/string.h>
71 #include <linux/workqueue.h>
74 unsigned char boot_ind; /* 0x80 - active */
75 unsigned char head; /* starting head */
76 unsigned char sector; /* starting sector */
77 unsigned char cyl; /* starting cylinder */
78 unsigned char sys_ind; /* What partition type */
79 unsigned char end_head; /* end head */
80 unsigned char end_sector; /* end sector */
81 unsigned char end_cyl; /* end cylinder */
82 __le32 start_sect; /* starting sector counting from 0 */
83 __le32 nr_sects; /* nr of sectors in partition */
84 } __attribute__((packed));
87 u64 nsecs[NR_STAT_GROUPS];
88 unsigned long sectors[NR_STAT_GROUPS];
89 unsigned long ios[NR_STAT_GROUPS];
90 unsigned long merges[NR_STAT_GROUPS];
91 unsigned long io_ticks;
92 unsigned long time_in_queue;
96 #define PARTITION_META_INFO_VOLNAMELTH 64
98 * Enough for the string representation of any kind of UUID plus NULL.
99 * EFI UUID is 36 characters. MSDOS UUID is 11 characters.
101 #define PARTITION_META_INFO_UUIDLTH (UUID_STRING_LEN + 1)
103 struct partition_meta_info {
104 char uuid[PARTITION_META_INFO_UUIDLTH];
105 u8 volname[PARTITION_META_INFO_VOLNAMELTH];
111 * nr_sects is protected by sequence counter. One might extend a
112 * partition while IO is happening to it and update of nr_sects
113 * can be non-atomic on 32bit machines with 64bit sector_t.
116 seqcount_t nr_sects_seq;
117 sector_t alignment_offset;
118 unsigned int discard_alignment;
120 struct kobject *holder_dir;
122 struct partition_meta_info *info;
123 #ifdef CONFIG_FAIL_MAKE_REQUEST
128 struct disk_stats __percpu *dkstats;
130 struct disk_stats dkstats;
132 struct percpu_ref ref;
133 struct rcu_work rcu_work;
136 #define GENHD_FL_REMOVABLE 1
138 #define GENHD_FL_MEDIA_CHANGE_NOTIFY 4
139 #define GENHD_FL_CD 8
140 #define GENHD_FL_UP 16
141 #define GENHD_FL_SUPPRESS_PARTITION_INFO 32
142 #define GENHD_FL_EXT_DEVT 64 /* allow extended devt */
143 #define GENHD_FL_NATIVE_CAPACITY 128
144 #define GENHD_FL_BLOCK_EVENTS_ON_EXCL_WRITE 256
145 #define GENHD_FL_NO_PART_SCAN 512
146 #define GENHD_FL_HIDDEN 1024
149 DISK_EVENT_MEDIA_CHANGE = 1 << 0, /* media changed */
150 DISK_EVENT_EJECT_REQUEST = 1 << 1, /* eject requested */
153 struct disk_part_tbl {
154 struct rcu_head rcu_head;
156 struct hd_struct __rcu *last_lookup;
157 struct hd_struct __rcu *part[];
163 #if defined(CONFIG_BLK_DEV_INTEGRITY)
165 struct blk_integrity {
166 const struct blk_integrity_profile *profile;
168 unsigned char tuple_size;
169 unsigned char interval_exp;
170 unsigned char tag_size;
173 #endif /* CONFIG_BLK_DEV_INTEGRITY */
176 /* major, first_minor and minors are input parameters only,
177 * don't use directly. Use disk_devt() and disk_max_parts().
179 int major; /* major number of driver */
181 int minors; /* maximum number of minors, =1 for
182 * disks that can't be partitioned. */
184 char disk_name[DISK_NAME_LEN]; /* name of major driver */
185 char *(*devnode)(struct gendisk *gd, umode_t *mode);
187 unsigned int events; /* supported events */
188 unsigned int async_events; /* async events, subset of all */
190 /* Array of pointers to partitions indexed by partno.
191 * Protected with matching bdev lock but stat and other
192 * non-critical accesses use RCU. Always access through
195 struct disk_part_tbl __rcu *part_tbl;
196 struct hd_struct part0;
198 const struct block_device_operations *fops;
199 struct request_queue *queue;
203 struct rw_semaphore lookup_sem;
204 struct kobject *slave_dir;
206 struct timer_rand_state *random;
207 atomic_t sync_io; /* RAID */
208 struct disk_events *ev;
209 #ifdef CONFIG_BLK_DEV_INTEGRITY
210 struct kobject integrity_kobj;
211 #endif /* CONFIG_BLK_DEV_INTEGRITY */
213 struct badblocks *bb;
214 struct lockdep_map lockdep_map;
217 static inline struct gendisk *part_to_disk(struct hd_struct *part)
221 return dev_to_disk(part_to_dev(part)->parent);
223 return dev_to_disk(part_to_dev(part));
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 MKDEV(disk->major, disk->first_minor);
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);
252 extern struct hd_struct *disk_get_part(struct gendisk *disk, int partno);
254 static inline void disk_put_part(struct hd_struct *part)
257 put_device(part_to_dev(part));
261 * Smarter partition iterator without context limits.
263 #define DISK_PITER_REVERSE (1 << 0) /* iterate in the reverse direction */
264 #define DISK_PITER_INCL_EMPTY (1 << 1) /* include 0-sized parts */
265 #define DISK_PITER_INCL_PART0 (1 << 2) /* include partition 0 */
266 #define DISK_PITER_INCL_EMPTY_PART0 (1 << 3) /* include empty partition 0 */
268 struct disk_part_iter {
269 struct gendisk *disk;
270 struct hd_struct *part;
275 extern void disk_part_iter_init(struct disk_part_iter *piter,
276 struct gendisk *disk, unsigned int flags);
277 extern struct hd_struct *disk_part_iter_next(struct disk_part_iter *piter);
278 extern void disk_part_iter_exit(struct disk_part_iter *piter);
280 extern struct hd_struct *disk_map_sector_rcu(struct gendisk *disk,
284 * Macros to operate on percpu disk statistics:
286 * {disk|part|all}_stat_{add|sub|inc|dec}() modify the stat counters
287 * and should be called between disk_stat_lock() and
288 * disk_stat_unlock().
290 * part_stat_read() can be called at any time.
292 * part_stat_{add|set_all}() and {init|free}_part_stats are for
296 #define part_stat_lock() ({ rcu_read_lock(); get_cpu(); })
297 #define part_stat_unlock() do { put_cpu(); rcu_read_unlock(); } while (0)
299 #define part_stat_get_cpu(part, field, cpu) \
300 (per_cpu_ptr((part)->dkstats, (cpu))->field)
302 #define part_stat_get(part, field) \
303 part_stat_get_cpu(part, field, smp_processor_id())
305 #define part_stat_read(part, field) \
307 typeof((part)->dkstats->field) res = 0; \
309 for_each_possible_cpu(_cpu) \
310 res += per_cpu_ptr((part)->dkstats, _cpu)->field; \
314 static inline void part_stat_set_all(struct hd_struct *part, int value)
318 for_each_possible_cpu(i)
319 memset(per_cpu_ptr(part->dkstats, i), value,
320 sizeof(struct disk_stats));
323 static inline int init_part_stats(struct hd_struct *part)
325 part->dkstats = alloc_percpu(struct disk_stats);
331 static inline void free_part_stats(struct hd_struct *part)
333 free_percpu(part->dkstats);
336 #else /* !CONFIG_SMP */
337 #define part_stat_lock() ({ rcu_read_lock(); 0; })
338 #define part_stat_unlock() rcu_read_unlock()
340 #define part_stat_get(part, field) ((part)->dkstats.field)
341 #define part_stat_get_cpu(part, field, cpu) part_stat_get(part, field)
342 #define part_stat_read(part, field) part_stat_get(part, field)
344 static inline void part_stat_set_all(struct hd_struct *part, int value)
346 memset(&part->dkstats, value, sizeof(struct disk_stats));
349 static inline int init_part_stats(struct hd_struct *part)
354 static inline void free_part_stats(struct hd_struct *part)
358 #endif /* CONFIG_SMP */
360 #define part_stat_read_msecs(part, which) \
361 div_u64(part_stat_read(part, nsecs[which]), NSEC_PER_MSEC)
363 #define part_stat_read_accum(part, field) \
364 (part_stat_read(part, field[STAT_READ]) + \
365 part_stat_read(part, field[STAT_WRITE]) + \
366 part_stat_read(part, field[STAT_DISCARD]))
368 #define __part_stat_add(part, field, addnd) \
369 (part_stat_get(part, field) += (addnd))
371 #define part_stat_add(part, field, addnd) do { \
372 __part_stat_add((part), field, addnd); \
373 if ((part)->partno) \
374 __part_stat_add(&part_to_disk((part))->part0, \
378 #define part_stat_dec(gendiskp, field) \
379 part_stat_add(gendiskp, field, -1)
380 #define part_stat_inc(gendiskp, field) \
381 part_stat_add(gendiskp, field, 1)
382 #define part_stat_sub(gendiskp, field, subnd) \
383 part_stat_add(gendiskp, field, -subnd)
385 #define part_stat_local_dec(gendiskp, field) \
386 local_dec(&(part_stat_get(gendiskp, field)))
387 #define part_stat_local_inc(gendiskp, field) \
388 local_inc(&(part_stat_get(gendiskp, field)))
389 #define part_stat_local_read(gendiskp, field) \
390 local_read(&(part_stat_get(gendiskp, field)))
391 #define part_stat_local_read_cpu(gendiskp, field, cpu) \
392 local_read(&(part_stat_get_cpu(gendiskp, field, cpu)))
394 void part_in_flight(struct request_queue *q, struct hd_struct *part,
395 unsigned int inflight[2]);
396 void part_in_flight_rw(struct request_queue *q, struct hd_struct *part,
397 unsigned int inflight[2]);
398 void part_dec_in_flight(struct request_queue *q, struct hd_struct *part,
400 void part_inc_in_flight(struct request_queue *q, struct hd_struct *part,
403 static inline struct partition_meta_info *alloc_part_info(struct gendisk *disk)
406 return kzalloc_node(sizeof(struct partition_meta_info),
407 GFP_KERNEL, disk->node_id);
408 return kzalloc(sizeof(struct partition_meta_info), GFP_KERNEL);
411 static inline void free_part_info(struct hd_struct *part)
416 void update_io_ticks(struct hd_struct *part, unsigned long now);
419 extern void device_add_disk(struct device *parent, struct gendisk *disk,
420 const struct attribute_group **groups);
421 static inline void add_disk(struct gendisk *disk)
423 device_add_disk(NULL, disk, NULL);
425 extern void device_add_disk_no_queue_reg(struct device *parent, struct gendisk *disk);
426 static inline void add_disk_no_queue_reg(struct gendisk *disk)
428 device_add_disk_no_queue_reg(NULL, disk);
431 extern void del_gendisk(struct gendisk *gp);
432 extern struct gendisk *get_gendisk(dev_t dev, int *partno);
433 extern struct block_device *bdget_disk(struct gendisk *disk, int partno);
435 extern void set_device_ro(struct block_device *bdev, int flag);
436 extern void set_disk_ro(struct gendisk *disk, int flag);
438 static inline int get_disk_ro(struct gendisk *disk)
440 return disk->part0.policy;
443 extern void disk_block_events(struct gendisk *disk);
444 extern void disk_unblock_events(struct gendisk *disk);
445 extern void disk_flush_events(struct gendisk *disk, unsigned int mask);
446 extern unsigned int disk_clear_events(struct gendisk *disk, unsigned int mask);
448 /* drivers/char/random.c */
449 extern void add_disk_randomness(struct gendisk *disk) __latent_entropy;
450 extern void rand_initialize_disk(struct gendisk *disk);
452 static inline sector_t get_start_sect(struct block_device *bdev)
454 return bdev->bd_part->start_sect;
456 static inline sector_t get_capacity(struct gendisk *disk)
458 return disk->part0.nr_sects;
460 static inline void set_capacity(struct gendisk *disk, sector_t size)
462 disk->part0.nr_sects = size;
465 #ifdef CONFIG_SOLARIS_X86_PARTITION
467 #define SOLARIS_X86_NUMSLICE 16
468 #define SOLARIS_X86_VTOC_SANE (0x600DDEEEUL)
470 struct solaris_x86_slice {
471 __le16 s_tag; /* ID tag of partition */
472 __le16 s_flag; /* permission flags */
473 __le32 s_start; /* start sector no of partition */
474 __le32 s_size; /* # of blocks in partition */
477 struct solaris_x86_vtoc {
478 unsigned int v_bootinfo[3]; /* info needed by mboot (unsupported) */
479 __le32 v_sanity; /* to verify vtoc sanity */
480 __le32 v_version; /* layout version */
481 char v_volume[8]; /* volume name */
482 __le16 v_sectorsz; /* sector size in bytes */
483 __le16 v_nparts; /* number of partitions */
484 unsigned int v_reserved[10]; /* free space */
485 struct solaris_x86_slice
486 v_slice[SOLARIS_X86_NUMSLICE]; /* slice headers */
487 unsigned int timestamp[SOLARIS_X86_NUMSLICE]; /* timestamp (unsupported) */
488 char v_asciilabel[128]; /* for compatibility */
491 #endif /* CONFIG_SOLARIS_X86_PARTITION */
493 #ifdef CONFIG_BSD_DISKLABEL
495 * BSD disklabel support by Yossi Gottlieb <yogo@math.tau.ac.il>
496 * updated by Marc Espie <Marc.Espie@openbsd.org>
499 /* check against BSD src/sys/sys/disklabel.h for consistency */
501 #define BSD_DISKMAGIC (0x82564557UL) /* The disk magic number */
502 #define BSD_MAXPARTITIONS 16
503 #define OPENBSD_MAXPARTITIONS 16
504 #define BSD_FS_UNUSED 0 /* disklabel unused partition entry ID */
505 struct bsd_disklabel {
506 __le32 d_magic; /* the magic number */
507 __s16 d_type; /* drive type */
508 __s16 d_subtype; /* controller/d_type specific */
509 char d_typename[16]; /* type name, e.g. "eagle" */
510 char d_packname[16]; /* pack identifier */
511 __u32 d_secsize; /* # of bytes per sector */
512 __u32 d_nsectors; /* # of data sectors per track */
513 __u32 d_ntracks; /* # of tracks per cylinder */
514 __u32 d_ncylinders; /* # of data cylinders per unit */
515 __u32 d_secpercyl; /* # of data sectors per cylinder */
516 __u32 d_secperunit; /* # of data sectors per unit */
517 __u16 d_sparespertrack; /* # of spare sectors per track */
518 __u16 d_sparespercyl; /* # of spare sectors per cylinder */
519 __u32 d_acylinders; /* # of alt. cylinders per unit */
520 __u16 d_rpm; /* rotational speed */
521 __u16 d_interleave; /* hardware sector interleave */
522 __u16 d_trackskew; /* sector 0 skew, per track */
523 __u16 d_cylskew; /* sector 0 skew, per cylinder */
524 __u32 d_headswitch; /* head switch time, usec */
525 __u32 d_trkseek; /* track-to-track seek, usec */
526 __u32 d_flags; /* generic flags */
528 __u32 d_drivedata[NDDATA]; /* drive-type specific information */
530 __u32 d_spare[NSPARE]; /* reserved for future use */
531 __le32 d_magic2; /* the magic number (again) */
532 __le16 d_checksum; /* xor of data incl. partitions */
534 /* filesystem and partition information: */
535 __le16 d_npartitions; /* number of partitions in following */
536 __le32 d_bbsize; /* size of boot area at sn0, bytes */
537 __le32 d_sbsize; /* max size of fs superblock, bytes */
538 struct bsd_partition { /* the partition table */
539 __le32 p_size; /* number of sectors in partition */
540 __le32 p_offset; /* starting sector */
541 __le32 p_fsize; /* filesystem basic fragment size */
542 __u8 p_fstype; /* filesystem type, see below */
543 __u8 p_frag; /* filesystem fragments per block */
544 __le16 p_cpg; /* filesystem cylinders per group */
545 } d_partitions[BSD_MAXPARTITIONS]; /* actually may be more */
548 #endif /* CONFIG_BSD_DISKLABEL */
550 #ifdef CONFIG_UNIXWARE_DISKLABEL
552 * Unixware slices support by Andrzej Krzysztofowicz <ankry@mif.pg.gda.pl>
553 * and Krzysztof G. Baranowski <kgb@knm.org.pl>
556 #define UNIXWARE_DISKMAGIC (0xCA5E600DUL) /* The disk magic number */
557 #define UNIXWARE_DISKMAGIC2 (0x600DDEEEUL) /* The slice table magic nr */
558 #define UNIXWARE_NUMSLICE 16
559 #define UNIXWARE_FS_UNUSED 0 /* Unused slice entry ID */
561 struct unixware_slice {
562 __le16 s_label; /* label */
563 __le16 s_flags; /* permission flags */
564 __le32 start_sect; /* starting sector */
565 __le32 nr_sects; /* number of sectors in slice */
568 struct unixware_disklabel {
569 __le32 d_type; /* drive type */
570 __le32 d_magic; /* the magic number */
571 __le32 d_version; /* version number */
572 char d_serial[12]; /* serial number of the device */
573 __le32 d_ncylinders; /* # of data cylinders per device */
574 __le32 d_ntracks; /* # of tracks per cylinder */
575 __le32 d_nsectors; /* # of data sectors per track */
576 __le32 d_secsize; /* # of bytes per sector */
577 __le32 d_part_start; /* # of first sector of this partition */
578 __le32 d_unknown1[12]; /* ? */
579 __le32 d_alt_tbl; /* byte offset of alternate table */
580 __le32 d_alt_len; /* byte length of alternate table */
581 __le32 d_phys_cyl; /* # of physical cylinders per device */
582 __le32 d_phys_trk; /* # of physical tracks per cylinder */
583 __le32 d_phys_sec; /* # of physical sectors per track */
584 __le32 d_phys_bytes; /* # of physical bytes per sector */
585 __le32 d_unknown2; /* ? */
586 __le32 d_unknown3; /* ? */
587 __le32 d_pad[8]; /* pad */
589 struct unixware_vtoc {
590 __le32 v_magic; /* the magic number */
591 __le32 v_version; /* version number */
592 char v_name[8]; /* volume name */
593 __le16 v_nslices; /* # of slices */
594 __le16 v_unknown1; /* ? */
595 __le32 v_reserved[10]; /* reserved */
596 struct unixware_slice
597 v_slice[UNIXWARE_NUMSLICE]; /* slice headers */
602 #endif /* CONFIG_UNIXWARE_DISKLABEL */
604 #ifdef CONFIG_MINIX_SUBPARTITION
605 # define MINIX_NR_SUBPARTITIONS 4
606 #endif /* CONFIG_MINIX_SUBPARTITION */
608 #define ADDPART_FLAG_NONE 0
609 #define ADDPART_FLAG_RAID 1
610 #define ADDPART_FLAG_WHOLEDISK 2
612 extern int blk_alloc_devt(struct hd_struct *part, dev_t *devt);
613 extern void blk_free_devt(dev_t devt);
614 extern dev_t blk_lookup_devt(const char *name, int partno);
615 extern char *disk_name (struct gendisk *hd, int partno, char *buf);
617 extern int disk_expand_part_tbl(struct gendisk *disk, int target);
618 extern int rescan_partitions(struct gendisk *disk, struct block_device *bdev);
619 extern int invalidate_partitions(struct gendisk *disk, struct block_device *bdev);
620 extern struct hd_struct * __must_check add_partition(struct gendisk *disk,
621 int partno, sector_t start,
622 sector_t len, int flags,
623 struct partition_meta_info
625 extern void __delete_partition(struct percpu_ref *);
626 extern void delete_partition(struct gendisk *, int);
627 extern void printk_all_partitions(void);
629 extern struct gendisk *__alloc_disk_node(int minors, int node_id);
630 extern struct kobject *get_disk_and_module(struct gendisk *disk);
631 extern void put_disk(struct gendisk *disk);
632 extern void put_disk_and_module(struct gendisk *disk);
633 extern void blk_register_region(dev_t devt, unsigned long range,
634 struct module *module,
635 struct kobject *(*probe)(dev_t, int *, void *),
636 int (*lock)(dev_t, void *),
638 extern void blk_unregister_region(dev_t devt, unsigned long range);
640 extern ssize_t part_size_show(struct device *dev,
641 struct device_attribute *attr, char *buf);
642 extern ssize_t part_stat_show(struct device *dev,
643 struct device_attribute *attr, char *buf);
644 extern ssize_t part_inflight_show(struct device *dev,
645 struct device_attribute *attr, char *buf);
646 #ifdef CONFIG_FAIL_MAKE_REQUEST
647 extern ssize_t part_fail_show(struct device *dev,
648 struct device_attribute *attr, char *buf);
649 extern ssize_t part_fail_store(struct device *dev,
650 struct device_attribute *attr,
651 const char *buf, size_t count);
652 #endif /* CONFIG_FAIL_MAKE_REQUEST */
654 #define alloc_disk_node(minors, node_id) \
656 static struct lock_class_key __key; \
657 const char *__name; \
658 struct gendisk *__disk; \
660 __name = "(gendisk_completion)"#minors"("#node_id")"; \
662 __disk = __alloc_disk_node(minors, node_id); \
665 lockdep_init_map(&__disk->lockdep_map, __name, &__key, 0); \
670 #define alloc_disk(minors) alloc_disk_node(minors, NUMA_NO_NODE)
672 static inline int hd_ref_init(struct hd_struct *part)
674 if (percpu_ref_init(&part->ref, __delete_partition, 0,
680 static inline void hd_struct_get(struct hd_struct *part)
682 percpu_ref_get(&part->ref);
685 static inline int hd_struct_try_get(struct hd_struct *part)
687 return percpu_ref_tryget_live(&part->ref);
690 static inline void hd_struct_put(struct hd_struct *part)
692 percpu_ref_put(&part->ref);
695 static inline void hd_struct_kill(struct hd_struct *part)
697 percpu_ref_kill(&part->ref);
700 static inline void hd_free_part(struct hd_struct *part)
702 free_part_stats(part);
703 free_part_info(part);
704 percpu_ref_exit(&part->ref);
708 * Any access of part->nr_sects which is not protected by partition
709 * bd_mutex or gendisk bdev bd_mutex, should be done using this
712 * Code written along the lines of i_size_read() and i_size_write().
713 * CONFIG_PREEMPT case optimizes the case of UP kernel with preemption
716 static inline sector_t part_nr_sects_read(struct hd_struct *part)
718 #if BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_SMP)
722 seq = read_seqcount_begin(&part->nr_sects_seq);
723 nr_sects = part->nr_sects;
724 } while (read_seqcount_retry(&part->nr_sects_seq, seq));
726 #elif BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_PREEMPT)
730 nr_sects = part->nr_sects;
734 return part->nr_sects;
739 * Should be called with mutex lock held (typically bd_mutex) of partition
740 * to provide mutual exlusion among writers otherwise seqcount might be
741 * left in wrong state leaving the readers spinning infinitely.
743 static inline void part_nr_sects_write(struct hd_struct *part, sector_t size)
745 #if BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_SMP)
746 write_seqcount_begin(&part->nr_sects_seq);
747 part->nr_sects = size;
748 write_seqcount_end(&part->nr_sects_seq);
749 #elif BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_PREEMPT)
751 part->nr_sects = size;
754 part->nr_sects = size;
758 #if defined(CONFIG_BLK_DEV_INTEGRITY)
759 extern void blk_integrity_add(struct gendisk *);
760 extern void blk_integrity_del(struct gendisk *);
761 #else /* CONFIG_BLK_DEV_INTEGRITY */
762 static inline void blk_integrity_add(struct gendisk *disk) { }
763 static inline void blk_integrity_del(struct gendisk *disk) { }
764 #endif /* CONFIG_BLK_DEV_INTEGRITY */
766 #else /* CONFIG_BLOCK */
768 static inline void printk_all_partitions(void) { }
770 static inline dev_t blk_lookup_devt(const char *name, int partno)
772 dev_t devt = MKDEV(0, 0);
775 #endif /* CONFIG_BLOCK */
777 #endif /* _LINUX_GENHD_H */