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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 28extern struct device_type part_type; 29extern struct kobject *block_depr; 30extern struct class block_class; 31 32enum { 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 72struct 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 85struct 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 101struct partition_meta_info { 102 char uuid[PARTITION_META_INFO_UUIDLTH]; 103 u8 volname[PARTITION_META_INFO_VOLNAMELTH]; 104}; 105 106struct 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 147enum { 148 DISK_EVENT_MEDIA_CHANGE = 1 << 0, /* media changed */ 149 DISK_EVENT_EJECT_REQUEST = 1 << 1, /* eject requested */ 150}; 151 152struct 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 159struct disk_events; 160struct badblocks; 161 162#if defined(CONFIG_BLK_DEV_INTEGRITY) 163 164struct 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 174struct 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 216static 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 227static 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 234static 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 240static inline dev_t disk_devt(struct gendisk *disk) 241{ 242 return MKDEV(disk->major, disk->first_minor); 243} 244 245static inline dev_t part_devt(struct hd_struct *part) 246{ 247 return part_to_dev(part)->devt; 248} 249 250extern struct hd_struct *__disk_get_part(struct gendisk *disk, int partno); 251extern struct hd_struct *disk_get_part(struct gendisk *disk, int partno); 252 253static 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 267struct disk_part_iter { 268 struct gendisk *disk; 269 struct hd_struct *part; 270 int idx; 271 unsigned int flags; 272}; 273 274extern void disk_part_iter_init(struct disk_part_iter *piter, 275 struct gendisk *disk, unsigned int flags); 276extern struct hd_struct *disk_part_iter_next(struct disk_part_iter *piter); 277extern void disk_part_iter_exit(struct disk_part_iter *piter); 278 279extern 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 310static 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 319static 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 327static 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 341static inline void part_stat_set_all(struct hd_struct *part, int value) 342{ 343 memset(&part->dkstats, value, sizeof(struct disk_stats)); 344} 345 346static inline int init_part_stats(struct hd_struct *part) 347{ 348 return 1; 349} 350 351static 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 379void part_in_flight(struct request_queue *q, struct hd_struct *part, 380 unsigned int inflight[2]); 381void part_in_flight_rw(struct request_queue *q, struct hd_struct *part, 382 unsigned int inflight[2]); 383void part_dec_in_flight(struct request_queue *q, struct hd_struct *part, 384 int rw); 385void part_inc_in_flight(struct request_queue *q, struct hd_struct *part, 386 int rw); 387 388static 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 396static inline void free_part_info(struct hd_struct *part) 397{ 398 kfree(part->info); 399} 400 401/* block/blk-core.c */ 402extern void part_round_stats(struct request_queue *q, int cpu, struct hd_struct *part); 403 404/* block/genhd.c */ 405extern void device_add_disk(struct device *parent, struct gendisk *disk, 406 const struct attribute_group **groups); 407static inline void add_disk(struct gendisk *disk) 408{ 409 device_add_disk(NULL, disk, NULL); 410} 411extern void device_add_disk_no_queue_reg(struct device *parent, struct gendisk *disk); 412static inline void add_disk_no_queue_reg(struct gendisk *disk) 413{ 414 device_add_disk_no_queue_reg(NULL, disk); 415} 416 417extern void del_gendisk(struct gendisk *gp); 418extern struct gendisk *get_gendisk(dev_t dev, int *partno); 419extern struct block_device *bdget_disk(struct gendisk *disk, int partno); 420 421extern void set_device_ro(struct block_device *bdev, int flag); 422extern void set_disk_ro(struct gendisk *disk, int flag); 423 424static inline int get_disk_ro(struct gendisk *disk) 425{ 426 return disk->part0.policy; 427} 428 429extern void disk_block_events(struct gendisk *disk); 430extern void disk_unblock_events(struct gendisk *disk); 431extern void disk_flush_events(struct gendisk *disk, unsigned int mask); 432extern unsigned int disk_clear_events(struct gendisk *disk, unsigned int mask); 433 434/* drivers/char/random.c */ 435extern void add_disk_randomness(struct gendisk *disk) __latent_entropy; 436extern void rand_initialize_disk(struct gendisk *disk); 437 438static inline sector_t get_start_sect(struct block_device *bdev) 439{ 440 return bdev->bd_part->start_sect; 441} 442static inline sector_t get_capacity(struct gendisk *disk) 443{ 444 return disk->part0.nr_sects; 445} 446static inline void set_capacity(struct gendisk *disk, sector_t size) 447{ 448 disk->part0.nr_sects = size; 449} 450 451#ifdef CONFIG_SOLARIS_X86_PARTITION 452 453#define SOLARIS_X86_NUMSLICE 16 454#define SOLARIS_X86_VTOC_SANE (0x600DDEEEUL) 455 456struct solaris_x86_slice { 457 __le16 s_tag; /* ID tag of partition */ 458 __le16 s_flag; /* permission flags */ 459 __le32 s_start; /* start sector no of partition */ 460 __le32 s_size; /* # of blocks in partition */ 461}; 462 463struct solaris_x86_vtoc { 464 unsigned int v_bootinfo[3]; /* info needed by mboot (unsupported) */ 465 __le32 v_sanity; /* to verify vtoc sanity */ 466 __le32 v_version; /* layout version */ 467 char v_volume[8]; /* volume name */ 468 __le16 v_sectorsz; /* sector size in bytes */ 469 __le16 v_nparts; /* number of partitions */ 470 unsigned int v_reserved[10]; /* free space */ 471 struct solaris_x86_slice 472 v_slice[SOLARIS_X86_NUMSLICE]; /* slice headers */ 473 unsigned int timestamp[SOLARIS_X86_NUMSLICE]; /* timestamp (unsupported) */ 474 char v_asciilabel[128]; /* for compatibility */ 475}; 476 477#endif /* CONFIG_SOLARIS_X86_PARTITION */ 478 479#ifdef CONFIG_BSD_DISKLABEL 480/* 481 * BSD disklabel support by Yossi Gottlieb <yogo@math.tau.ac.il> 482 * updated by Marc Espie <Marc.Espie@openbsd.org> 483 */ 484 485/* check against BSD src/sys/sys/disklabel.h for consistency */ 486 487#define BSD_DISKMAGIC (0x82564557UL) /* The disk magic number */ 488#define BSD_MAXPARTITIONS 16 489#define OPENBSD_MAXPARTITIONS 16 490#define BSD_FS_UNUSED 0 /* disklabel unused partition entry ID */ 491struct bsd_disklabel { 492 __le32 d_magic; /* the magic number */ 493 __s16 d_type; /* drive type */ 494 __s16 d_subtype; /* controller/d_type specific */ 495 char d_typename[16]; /* type name, e.g. "eagle" */ 496 char d_packname[16]; /* pack identifier */ 497 __u32 d_secsize; /* # of bytes per sector */ 498 __u32 d_nsectors; /* # of data sectors per track */ 499 __u32 d_ntracks; /* # of tracks per cylinder */ 500 __u32 d_ncylinders; /* # of data cylinders per unit */ 501 __u32 d_secpercyl; /* # of data sectors per cylinder */ 502 __u32 d_secperunit; /* # of data sectors per unit */ 503 __u16 d_sparespertrack; /* # of spare sectors per track */ 504 __u16 d_sparespercyl; /* # of spare sectors per cylinder */ 505 __u32 d_acylinders; /* # of alt. cylinders per unit */ 506 __u16 d_rpm; /* rotational speed */ 507 __u16 d_interleave; /* hardware sector interleave */ 508 __u16 d_trackskew; /* sector 0 skew, per track */ 509 __u16 d_cylskew; /* sector 0 skew, per cylinder */ 510 __u32 d_headswitch; /* head switch time, usec */ 511 __u32 d_trkseek; /* track-to-track seek, usec */ 512 __u32 d_flags; /* generic flags */ 513#define NDDATA 5 514 __u32 d_drivedata[NDDATA]; /* drive-type specific information */ 515#define NSPARE 5 516 __u32 d_spare[NSPARE]; /* reserved for future use */ 517 __le32 d_magic2; /* the magic number (again) */ 518 __le16 d_checksum; /* xor of data incl. partitions */ 519 520 /* filesystem and partition information: */ 521 __le16 d_npartitions; /* number of partitions in following */ 522 __le32 d_bbsize; /* size of boot area at sn0, bytes */ 523 __le32 d_sbsize; /* max size of fs superblock, bytes */ 524 struct bsd_partition { /* the partition table */ 525 __le32 p_size; /* number of sectors in partition */ 526 __le32 p_offset; /* starting sector */ 527 __le32 p_fsize; /* filesystem basic fragment size */ 528 __u8 p_fstype; /* filesystem type, see below */ 529 __u8 p_frag; /* filesystem fragments per block */ 530 __le16 p_cpg; /* filesystem cylinders per group */ 531 } d_partitions[BSD_MAXPARTITIONS]; /* actually may be more */ 532}; 533 534#endif /* CONFIG_BSD_DISKLABEL */ 535 536#ifdef CONFIG_UNIXWARE_DISKLABEL 537/* 538 * Unixware slices support by Andrzej Krzysztofowicz <ankry@mif.pg.gda.pl> 539 * and Krzysztof G. Baranowski <kgb@knm.org.pl> 540 */ 541 542#define UNIXWARE_DISKMAGIC (0xCA5E600DUL) /* The disk magic number */ 543#define UNIXWARE_DISKMAGIC2 (0x600DDEEEUL) /* The slice table magic nr */ 544#define UNIXWARE_NUMSLICE 16 545#define UNIXWARE_FS_UNUSED 0 /* Unused slice entry ID */ 546 547struct unixware_slice { 548 __le16 s_label; /* label */ 549 __le16 s_flags; /* permission flags */ 550 __le32 start_sect; /* starting sector */ 551 __le32 nr_sects; /* number of sectors in slice */ 552}; 553 554struct unixware_disklabel { 555 __le32 d_type; /* drive type */ 556 __le32 d_magic; /* the magic number */ 557 __le32 d_version; /* version number */ 558 char d_serial[12]; /* serial number of the device */ 559 __le32 d_ncylinders; /* # of data cylinders per device */ 560 __le32 d_ntracks; /* # of tracks per cylinder */ 561 __le32 d_nsectors; /* # of data sectors per track */ 562 __le32 d_secsize; /* # of bytes per sector */ 563 __le32 d_part_start; /* # of first sector of this partition */ 564 __le32 d_unknown1[12]; /* ? */ 565 __le32 d_alt_tbl; /* byte offset of alternate table */ 566 __le32 d_alt_len; /* byte length of alternate table */ 567 __le32 d_phys_cyl; /* # of physical cylinders per device */ 568 __le32 d_phys_trk; /* # of physical tracks per cylinder */ 569 __le32 d_phys_sec; /* # of physical sectors per track */ 570 __le32 d_phys_bytes; /* # of physical bytes per sector */ 571 __le32 d_unknown2; /* ? */ 572 __le32 d_unknown3; /* ? */ 573 __le32 d_pad[8]; /* pad */ 574 575 struct unixware_vtoc { 576 __le32 v_magic; /* the magic number */ 577 __le32 v_version; /* version number */ 578 char v_name[8]; /* volume name */ 579 __le16 v_nslices; /* # of slices */ 580 __le16 v_unknown1; /* ? */ 581 __le32 v_reserved[10]; /* reserved */ 582 struct unixware_slice 583 v_slice[UNIXWARE_NUMSLICE]; /* slice headers */ 584 } vtoc; 585 586}; /* 408 */ 587 588#endif /* CONFIG_UNIXWARE_DISKLABEL */ 589 590#ifdef CONFIG_MINIX_SUBPARTITION 591# define MINIX_NR_SUBPARTITIONS 4 592#endif /* CONFIG_MINIX_SUBPARTITION */ 593 594#define ADDPART_FLAG_NONE 0 595#define ADDPART_FLAG_RAID 1 596#define ADDPART_FLAG_WHOLEDISK 2 597 598extern int blk_alloc_devt(struct hd_struct *part, dev_t *devt); 599extern void blk_free_devt(dev_t devt); 600extern dev_t blk_lookup_devt(const char *name, int partno); 601extern char *disk_name (struct gendisk *hd, int partno, char *buf); 602 603extern int disk_expand_part_tbl(struct gendisk *disk, int target); 604extern int rescan_partitions(struct gendisk *disk, struct block_device *bdev); 605extern int invalidate_partitions(struct gendisk *disk, struct block_device *bdev); 606extern struct hd_struct * __must_check add_partition(struct gendisk *disk, 607 int partno, sector_t start, 608 sector_t len, int flags, 609 struct partition_meta_info 610 *info); 611extern void __delete_partition(struct percpu_ref *); 612extern void delete_partition(struct gendisk *, int); 613extern void printk_all_partitions(void); 614 615extern struct gendisk *__alloc_disk_node(int minors, int node_id); 616extern struct kobject *get_disk_and_module(struct gendisk *disk); 617extern void put_disk(struct gendisk *disk); 618extern void put_disk_and_module(struct gendisk *disk); 619extern void blk_register_region(dev_t devt, unsigned long range, 620 struct module *module, 621 struct kobject *(*probe)(dev_t, int *, void *), 622 int (*lock)(dev_t, void *), 623 void *data); 624extern void blk_unregister_region(dev_t devt, unsigned long range); 625 626extern ssize_t part_size_show(struct device *dev, 627 struct device_attribute *attr, char *buf); 628extern ssize_t part_stat_show(struct device *dev, 629 struct device_attribute *attr, char *buf); 630extern ssize_t part_inflight_show(struct device *dev, 631 struct device_attribute *attr, char *buf); 632#ifdef CONFIG_FAIL_MAKE_REQUEST 633extern ssize_t part_fail_show(struct device *dev, 634 struct device_attribute *attr, char *buf); 635extern ssize_t part_fail_store(struct device *dev, 636 struct device_attribute *attr, 637 const char *buf, size_t count); 638#endif /* CONFIG_FAIL_MAKE_REQUEST */ 639 640#define alloc_disk_node(minors, node_id) \ 641({ \ 642 static struct lock_class_key __key; \ 643 const char *__name; \ 644 struct gendisk *__disk; \ 645 \ 646 __name = "(gendisk_completion)"#minors"("#node_id")"; \ 647 \ 648 __disk = __alloc_disk_node(minors, node_id); \ 649 \ 650 if (__disk) \ 651 lockdep_init_map(&__disk->lockdep_map, __name, &__key, 0); \ 652 \ 653 __disk; \ 654}) 655 656#define alloc_disk(minors) alloc_disk_node(minors, NUMA_NO_NODE) 657 658static inline int hd_ref_init(struct hd_struct *part) 659{ 660 if (percpu_ref_init(&part->ref, __delete_partition, 0, 661 GFP_KERNEL)) 662 return -ENOMEM; 663 return 0; 664} 665 666static inline void hd_struct_get(struct hd_struct *part) 667{ 668 percpu_ref_get(&part->ref); 669} 670 671static inline int hd_struct_try_get(struct hd_struct *part) 672{ 673 return percpu_ref_tryget_live(&part->ref); 674} 675 676static inline void hd_struct_put(struct hd_struct *part) 677{ 678 percpu_ref_put(&part->ref); 679} 680 681static inline void hd_struct_kill(struct hd_struct *part) 682{ 683 percpu_ref_kill(&part->ref); 684} 685 686static inline void hd_free_part(struct hd_struct *part) 687{ 688 free_part_stats(part); 689 free_part_info(part); 690 percpu_ref_exit(&part->ref); 691} 692 693/* 694 * Any access of part->nr_sects which is not protected by partition 695 * bd_mutex or gendisk bdev bd_mutex, should be done using this 696 * accessor function. 697 * 698 * Code written along the lines of i_size_read() and i_size_write(). 699 * CONFIG_PREEMPT case optimizes the case of UP kernel with preemption 700 * on. 701 */ 702static inline sector_t part_nr_sects_read(struct hd_struct *part) 703{ 704#if BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_SMP) 705 sector_t nr_sects; 706 unsigned seq; 707 do { 708 seq = read_seqcount_begin(&part->nr_sects_seq); 709 nr_sects = part->nr_sects; 710 } while (read_seqcount_retry(&part->nr_sects_seq, seq)); 711 return nr_sects; 712#elif BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_PREEMPT) 713 sector_t nr_sects; 714 715 preempt_disable(); 716 nr_sects = part->nr_sects; 717 preempt_enable(); 718 return nr_sects; 719#else 720 return part->nr_sects; 721#endif 722} 723 724/* 725 * Should be called with mutex lock held (typically bd_mutex) of partition 726 * to provide mutual exlusion among writers otherwise seqcount might be 727 * left in wrong state leaving the readers spinning infinitely. 728 */ 729static inline void part_nr_sects_write(struct hd_struct *part, sector_t size) 730{ 731#if BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_SMP) 732 write_seqcount_begin(&part->nr_sects_seq); 733 part->nr_sects = size; 734 write_seqcount_end(&part->nr_sects_seq); 735#elif BITS_PER_LONG==32 && defined(CONFIG_LBDAF) && defined(CONFIG_PREEMPT) 736 preempt_disable(); 737 part->nr_sects = size; 738 preempt_enable(); 739#else 740 part->nr_sects = size; 741#endif 742} 743 744#if defined(CONFIG_BLK_DEV_INTEGRITY) 745extern void blk_integrity_add(struct gendisk *); 746extern void blk_integrity_del(struct gendisk *); 747#else /* CONFIG_BLK_DEV_INTEGRITY */ 748static inline void blk_integrity_add(struct gendisk *disk) { } 749static inline void blk_integrity_del(struct gendisk *disk) { } 750#endif /* CONFIG_BLK_DEV_INTEGRITY */ 751 752#else /* CONFIG_BLOCK */ 753 754static inline void printk_all_partitions(void) { } 755 756static inline dev_t blk_lookup_devt(const char *name, int partno) 757{ 758 dev_t devt = MKDEV(0, 0); 759 return devt; 760} 761#endif /* CONFIG_BLOCK */ 762 763#endif /* _LINUX_GENHD_H */