genhd.h 17 KB

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  1. #ifndef _LINUX_GENHD_H
  2. #define _LINUX_GENHD_H
  3. /*
  4. * genhd.h Copyright (C) 1992 Drew Eckhardt
  5. * Generic hard disk header file by
  6. * Drew Eckhardt
  7. *
  8. * <drew@colorado.edu>
  9. */
  10. #include <linux/types.h>
  11. #include <linux/kdev_t.h>
  12. #include <linux/rcupdate.h>
  13. #ifdef CONFIG_BLOCK
  14. #define kobj_to_dev(k) container_of((k), struct device, kobj)
  15. #define dev_to_disk(device) container_of((device), struct gendisk, part0.__dev)
  16. #define dev_to_part(device) container_of((device), struct hd_struct, __dev)
  17. #define disk_to_dev(disk) (&(disk)->part0.__dev)
  18. #define part_to_dev(part) (&((part)->__dev))
  19. extern struct device_type part_type;
  20. extern struct kobject *block_depr;
  21. extern struct class block_class;
  22. enum {
  23. /* These three have identical behaviour; use the second one if DOS FDISK gets
  24. confused about extended/logical partitions starting past cylinder 1023. */
  25. DOS_EXTENDED_PARTITION = 5,
  26. LINUX_EXTENDED_PARTITION = 0x85,
  27. WIN98_EXTENDED_PARTITION = 0x0f,
  28. SUN_WHOLE_DISK = DOS_EXTENDED_PARTITION,
  29. LINUX_SWAP_PARTITION = 0x82,
  30. LINUX_DATA_PARTITION = 0x83,
  31. LINUX_LVM_PARTITION = 0x8e,
  32. LINUX_RAID_PARTITION = 0xfd, /* autodetect RAID partition */
  33. SOLARIS_X86_PARTITION = LINUX_SWAP_PARTITION,
  34. NEW_SOLARIS_X86_PARTITION = 0xbf,
  35. DM6_AUX1PARTITION = 0x51, /* no DDO: use xlated geom */
  36. DM6_AUX3PARTITION = 0x53, /* no DDO: use xlated geom */
  37. DM6_PARTITION = 0x54, /* has DDO: use xlated geom & offset */
  38. EZD_PARTITION = 0x55, /* EZ-DRIVE */
  39. FREEBSD_PARTITION = 0xa5, /* FreeBSD Partition ID */
  40. OPENBSD_PARTITION = 0xa6, /* OpenBSD Partition ID */
  41. NETBSD_PARTITION = 0xa9, /* NetBSD Partition ID */
  42. BSDI_PARTITION = 0xb7, /* BSDI Partition ID */
  43. MINIX_PARTITION = 0x81, /* Minix Partition ID */
  44. UNIXWARE_PARTITION = 0x63, /* Same as GNU_HURD and SCO Unix */
  45. };
  46. #define DISK_MAX_PARTS 256
  47. #define DISK_NAME_LEN 32
  48. #include <linux/major.h>
  49. #include <linux/device.h>
  50. #include <linux/smp.h>
  51. #include <linux/string.h>
  52. #include <linux/fs.h>
  53. #include <linux/workqueue.h>
  54. struct partition {
  55. unsigned char boot_ind; /* 0x80 - active */
  56. unsigned char head; /* starting head */
  57. unsigned char sector; /* starting sector */
  58. unsigned char cyl; /* starting cylinder */
  59. unsigned char sys_ind; /* What partition type */
  60. unsigned char end_head; /* end head */
  61. unsigned char end_sector; /* end sector */
  62. unsigned char end_cyl; /* end cylinder */
  63. __le32 start_sect; /* starting sector counting from 0 */
  64. __le32 nr_sects; /* nr of sectors in partition */
  65. } __attribute__((packed));
  66. struct disk_stats {
  67. unsigned long sectors[2]; /* READs and WRITEs */
  68. unsigned long ios[2];
  69. unsigned long merges[2];
  70. unsigned long ticks[2];
  71. unsigned long io_ticks;
  72. unsigned long time_in_queue;
  73. };
  74. struct hd_struct {
  75. sector_t start_sect;
  76. sector_t nr_sects;
  77. sector_t alignment_offset;
  78. struct device __dev;
  79. struct kobject *holder_dir;
  80. int policy, partno;
  81. #ifdef CONFIG_FAIL_MAKE_REQUEST
  82. int make_it_fail;
  83. #endif
  84. unsigned long stamp;
  85. int in_flight;
  86. #ifdef CONFIG_SMP
  87. struct disk_stats *dkstats;
  88. #else
  89. struct disk_stats dkstats;
  90. #endif
  91. struct rcu_head rcu_head;
  92. };
  93. #define GENHD_FL_REMOVABLE 1
  94. #define GENHD_FL_DRIVERFS 2
  95. #define GENHD_FL_MEDIA_CHANGE_NOTIFY 4
  96. #define GENHD_FL_CD 8
  97. #define GENHD_FL_UP 16
  98. #define GENHD_FL_SUPPRESS_PARTITION_INFO 32
  99. #define GENHD_FL_EXT_DEVT 64 /* allow extended devt */
  100. #define GENHD_FL_NATIVE_CAPACITY 128
  101. #define BLK_SCSI_MAX_CMDS (256)
  102. #define BLK_SCSI_CMD_PER_LONG (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
  103. struct blk_scsi_cmd_filter {
  104. unsigned long read_ok[BLK_SCSI_CMD_PER_LONG];
  105. unsigned long write_ok[BLK_SCSI_CMD_PER_LONG];
  106. struct kobject kobj;
  107. };
  108. struct disk_part_tbl {
  109. struct rcu_head rcu_head;
  110. int len;
  111. struct hd_struct *last_lookup;
  112. struct hd_struct *part[];
  113. };
  114. struct gendisk {
  115. /* major, first_minor and minors are input parameters only,
  116. * don't use directly. Use disk_devt() and disk_max_parts().
  117. */
  118. int major; /* major number of driver */
  119. int first_minor;
  120. int minors; /* maximum number of minors, =1 for
  121. * disks that can't be partitioned. */
  122. char disk_name[DISK_NAME_LEN]; /* name of major driver */
  123. char *(*devnode)(struct gendisk *gd, mode_t *mode);
  124. /* Array of pointers to partitions indexed by partno.
  125. * Protected with matching bdev lock but stat and other
  126. * non-critical accesses use RCU. Always access through
  127. * helpers.
  128. */
  129. struct disk_part_tbl *part_tbl;
  130. struct hd_struct part0;
  131. const struct block_device_operations *fops;
  132. struct request_queue *queue;
  133. void *private_data;
  134. int flags;
  135. struct device *driverfs_dev; // FIXME: remove
  136. struct kobject *slave_dir;
  137. struct timer_rand_state *random;
  138. atomic_t sync_io; /* RAID */
  139. struct work_struct async_notify;
  140. #ifdef CONFIG_BLK_DEV_INTEGRITY
  141. struct blk_integrity *integrity;
  142. #endif
  143. int node_id;
  144. };
  145. static inline struct gendisk *part_to_disk(struct hd_struct *part)
  146. {
  147. if (likely(part)) {
  148. if (part->partno)
  149. return dev_to_disk(part_to_dev(part)->parent);
  150. else
  151. return dev_to_disk(part_to_dev(part));
  152. }
  153. return NULL;
  154. }
  155. static inline int disk_max_parts(struct gendisk *disk)
  156. {
  157. if (disk->flags & GENHD_FL_EXT_DEVT)
  158. return DISK_MAX_PARTS;
  159. return disk->minors;
  160. }
  161. static inline bool disk_partitionable(struct gendisk *disk)
  162. {
  163. return disk_max_parts(disk) > 1;
  164. }
  165. static inline dev_t disk_devt(struct gendisk *disk)
  166. {
  167. return disk_to_dev(disk)->devt;
  168. }
  169. static inline dev_t part_devt(struct hd_struct *part)
  170. {
  171. return part_to_dev(part)->devt;
  172. }
  173. extern struct hd_struct *disk_get_part(struct gendisk *disk, int partno);
  174. static inline void disk_put_part(struct hd_struct *part)
  175. {
  176. if (likely(part))
  177. put_device(part_to_dev(part));
  178. }
  179. /*
  180. * Smarter partition iterator without context limits.
  181. */
  182. #define DISK_PITER_REVERSE (1 << 0) /* iterate in the reverse direction */
  183. #define DISK_PITER_INCL_EMPTY (1 << 1) /* include 0-sized parts */
  184. #define DISK_PITER_INCL_PART0 (1 << 2) /* include partition 0 */
  185. #define DISK_PITER_INCL_EMPTY_PART0 (1 << 3) /* include empty partition 0 */
  186. struct disk_part_iter {
  187. struct gendisk *disk;
  188. struct hd_struct *part;
  189. int idx;
  190. unsigned int flags;
  191. };
  192. extern void disk_part_iter_init(struct disk_part_iter *piter,
  193. struct gendisk *disk, unsigned int flags);
  194. extern struct hd_struct *disk_part_iter_next(struct disk_part_iter *piter);
  195. extern void disk_part_iter_exit(struct disk_part_iter *piter);
  196. extern struct hd_struct *disk_map_sector_rcu(struct gendisk *disk,
  197. sector_t sector);
  198. /*
  199. * Macros to operate on percpu disk statistics:
  200. *
  201. * {disk|part|all}_stat_{add|sub|inc|dec}() modify the stat counters
  202. * and should be called between disk_stat_lock() and
  203. * disk_stat_unlock().
  204. *
  205. * part_stat_read() can be called at any time.
  206. *
  207. * part_stat_{add|set_all}() and {init|free}_part_stats are for
  208. * internal use only.
  209. */
  210. #ifdef CONFIG_SMP
  211. #define part_stat_lock() ({ rcu_read_lock(); get_cpu(); })
  212. #define part_stat_unlock() do { put_cpu(); rcu_read_unlock(); } while (0)
  213. #define __part_stat_add(cpu, part, field, addnd) \
  214. (per_cpu_ptr((part)->dkstats, (cpu))->field += (addnd))
  215. #define part_stat_read(part, field) \
  216. ({ \
  217. typeof((part)->dkstats->field) res = 0; \
  218. int i; \
  219. for_each_possible_cpu(i) \
  220. res += per_cpu_ptr((part)->dkstats, i)->field; \
  221. res; \
  222. })
  223. static inline void part_stat_set_all(struct hd_struct *part, int value)
  224. {
  225. int i;
  226. for_each_possible_cpu(i)
  227. memset(per_cpu_ptr(part->dkstats, i), value,
  228. sizeof(struct disk_stats));
  229. }
  230. static inline int init_part_stats(struct hd_struct *part)
  231. {
  232. part->dkstats = alloc_percpu(struct disk_stats);
  233. if (!part->dkstats)
  234. return 0;
  235. return 1;
  236. }
  237. static inline void free_part_stats(struct hd_struct *part)
  238. {
  239. free_percpu(part->dkstats);
  240. }
  241. #else /* !CONFIG_SMP */
  242. #define part_stat_lock() ({ rcu_read_lock(); 0; })
  243. #define part_stat_unlock() rcu_read_unlock()
  244. #define __part_stat_add(cpu, part, field, addnd) \
  245. ((part)->dkstats.field += addnd)
  246. #define part_stat_read(part, field) ((part)->dkstats.field)
  247. static inline void part_stat_set_all(struct hd_struct *part, int value)
  248. {
  249. memset(&part->dkstats, value, sizeof(struct disk_stats));
  250. }
  251. static inline int init_part_stats(struct hd_struct *part)
  252. {
  253. return 1;
  254. }
  255. static inline void free_part_stats(struct hd_struct *part)
  256. {
  257. }
  258. #endif /* CONFIG_SMP */
  259. #define part_stat_add(cpu, part, field, addnd) do { \
  260. __part_stat_add((cpu), (part), field, addnd); \
  261. if ((part)->partno) \
  262. __part_stat_add((cpu), &part_to_disk((part))->part0, \
  263. field, addnd); \
  264. } while (0)
  265. #define part_stat_dec(cpu, gendiskp, field) \
  266. part_stat_add(cpu, gendiskp, field, -1)
  267. #define part_stat_inc(cpu, gendiskp, field) \
  268. part_stat_add(cpu, gendiskp, field, 1)
  269. #define part_stat_sub(cpu, gendiskp, field, subnd) \
  270. part_stat_add(cpu, gendiskp, field, -subnd)
  271. static inline void part_inc_in_flight(struct hd_struct *part)
  272. {
  273. part->in_flight++;
  274. if (part->partno)
  275. part_to_disk(part)->part0.in_flight++;
  276. }
  277. static inline void part_dec_in_flight(struct hd_struct *part)
  278. {
  279. part->in_flight--;
  280. if (part->partno)
  281. part_to_disk(part)->part0.in_flight--;
  282. }
  283. /* block/blk-core.c */
  284. extern void part_round_stats(int cpu, struct hd_struct *part);
  285. /* block/genhd.c */
  286. extern void add_disk(struct gendisk *disk);
  287. extern void del_gendisk(struct gendisk *gp);
  288. extern void unlink_gendisk(struct gendisk *gp);
  289. extern struct gendisk *get_gendisk(dev_t dev, int *partno);
  290. extern struct block_device *bdget_disk(struct gendisk *disk, int partno);
  291. extern void set_device_ro(struct block_device *bdev, int flag);
  292. extern void set_disk_ro(struct gendisk *disk, int flag);
  293. static inline int get_disk_ro(struct gendisk *disk)
  294. {
  295. return disk->part0.policy;
  296. }
  297. /* drivers/char/random.c */
  298. extern void add_disk_randomness(struct gendisk *disk);
  299. extern void rand_initialize_disk(struct gendisk *disk);
  300. static inline sector_t get_start_sect(struct block_device *bdev)
  301. {
  302. return bdev->bd_part->start_sect;
  303. }
  304. static inline sector_t get_capacity(struct gendisk *disk)
  305. {
  306. return disk->part0.nr_sects;
  307. }
  308. static inline void set_capacity(struct gendisk *disk, sector_t size)
  309. {
  310. disk->part0.nr_sects = size;
  311. }
  312. #ifdef CONFIG_SOLARIS_X86_PARTITION
  313. #define SOLARIS_X86_NUMSLICE 16
  314. #define SOLARIS_X86_VTOC_SANE (0x600DDEEEUL)
  315. struct solaris_x86_slice {
  316. __le16 s_tag; /* ID tag of partition */
  317. __le16 s_flag; /* permission flags */
  318. __le32 s_start; /* start sector no of partition */
  319. __le32 s_size; /* # of blocks in partition */
  320. };
  321. struct solaris_x86_vtoc {
  322. unsigned int v_bootinfo[3]; /* info needed by mboot (unsupported) */
  323. __le32 v_sanity; /* to verify vtoc sanity */
  324. __le32 v_version; /* layout version */
  325. char v_volume[8]; /* volume name */
  326. __le16 v_sectorsz; /* sector size in bytes */
  327. __le16 v_nparts; /* number of partitions */
  328. unsigned int v_reserved[10]; /* free space */
  329. struct solaris_x86_slice
  330. v_slice[SOLARIS_X86_NUMSLICE]; /* slice headers */
  331. unsigned int timestamp[SOLARIS_X86_NUMSLICE]; /* timestamp (unsupported) */
  332. char v_asciilabel[128]; /* for compatibility */
  333. };
  334. #endif /* CONFIG_SOLARIS_X86_PARTITION */
  335. #ifdef CONFIG_BSD_DISKLABEL
  336. /*
  337. * BSD disklabel support by Yossi Gottlieb <yogo@math.tau.ac.il>
  338. * updated by Marc Espie <Marc.Espie@openbsd.org>
  339. */
  340. /* check against BSD src/sys/sys/disklabel.h for consistency */
  341. #define BSD_DISKMAGIC (0x82564557UL) /* The disk magic number */
  342. #define BSD_MAXPARTITIONS 16
  343. #define OPENBSD_MAXPARTITIONS 16
  344. #define BSD_FS_UNUSED 0 /* disklabel unused partition entry ID */
  345. struct bsd_disklabel {
  346. __le32 d_magic; /* the magic number */
  347. __s16 d_type; /* drive type */
  348. __s16 d_subtype; /* controller/d_type specific */
  349. char d_typename[16]; /* type name, e.g. "eagle" */
  350. char d_packname[16]; /* pack identifier */
  351. __u32 d_secsize; /* # of bytes per sector */
  352. __u32 d_nsectors; /* # of data sectors per track */
  353. __u32 d_ntracks; /* # of tracks per cylinder */
  354. __u32 d_ncylinders; /* # of data cylinders per unit */
  355. __u32 d_secpercyl; /* # of data sectors per cylinder */
  356. __u32 d_secperunit; /* # of data sectors per unit */
  357. __u16 d_sparespertrack; /* # of spare sectors per track */
  358. __u16 d_sparespercyl; /* # of spare sectors per cylinder */
  359. __u32 d_acylinders; /* # of alt. cylinders per unit */
  360. __u16 d_rpm; /* rotational speed */
  361. __u16 d_interleave; /* hardware sector interleave */
  362. __u16 d_trackskew; /* sector 0 skew, per track */
  363. __u16 d_cylskew; /* sector 0 skew, per cylinder */
  364. __u32 d_headswitch; /* head switch time, usec */
  365. __u32 d_trkseek; /* track-to-track seek, usec */
  366. __u32 d_flags; /* generic flags */
  367. #define NDDATA 5
  368. __u32 d_drivedata[NDDATA]; /* drive-type specific information */
  369. #define NSPARE 5
  370. __u32 d_spare[NSPARE]; /* reserved for future use */
  371. __le32 d_magic2; /* the magic number (again) */
  372. __le16 d_checksum; /* xor of data incl. partitions */
  373. /* filesystem and partition information: */
  374. __le16 d_npartitions; /* number of partitions in following */
  375. __le32 d_bbsize; /* size of boot area at sn0, bytes */
  376. __le32 d_sbsize; /* max size of fs superblock, bytes */
  377. struct bsd_partition { /* the partition table */
  378. __le32 p_size; /* number of sectors in partition */
  379. __le32 p_offset; /* starting sector */
  380. __le32 p_fsize; /* filesystem basic fragment size */
  381. __u8 p_fstype; /* filesystem type, see below */
  382. __u8 p_frag; /* filesystem fragments per block */
  383. __le16 p_cpg; /* filesystem cylinders per group */
  384. } d_partitions[BSD_MAXPARTITIONS]; /* actually may be more */
  385. };
  386. #endif /* CONFIG_BSD_DISKLABEL */
  387. #ifdef CONFIG_UNIXWARE_DISKLABEL
  388. /*
  389. * Unixware slices support by Andrzej Krzysztofowicz <ankry@mif.pg.gda.pl>
  390. * and Krzysztof G. Baranowski <kgb@knm.org.pl>
  391. */
  392. #define UNIXWARE_DISKMAGIC (0xCA5E600DUL) /* The disk magic number */
  393. #define UNIXWARE_DISKMAGIC2 (0x600DDEEEUL) /* The slice table magic nr */
  394. #define UNIXWARE_NUMSLICE 16
  395. #define UNIXWARE_FS_UNUSED 0 /* Unused slice entry ID */
  396. struct unixware_slice {
  397. __le16 s_label; /* label */
  398. __le16 s_flags; /* permission flags */
  399. __le32 start_sect; /* starting sector */
  400. __le32 nr_sects; /* number of sectors in slice */
  401. };
  402. struct unixware_disklabel {
  403. __le32 d_type; /* drive type */
  404. __le32 d_magic; /* the magic number */
  405. __le32 d_version; /* version number */
  406. char d_serial[12]; /* serial number of the device */
  407. __le32 d_ncylinders; /* # of data cylinders per device */
  408. __le32 d_ntracks; /* # of tracks per cylinder */
  409. __le32 d_nsectors; /* # of data sectors per track */
  410. __le32 d_secsize; /* # of bytes per sector */
  411. __le32 d_part_start; /* # of first sector of this partition */
  412. __le32 d_unknown1[12]; /* ? */
  413. __le32 d_alt_tbl; /* byte offset of alternate table */
  414. __le32 d_alt_len; /* byte length of alternate table */
  415. __le32 d_phys_cyl; /* # of physical cylinders per device */
  416. __le32 d_phys_trk; /* # of physical tracks per cylinder */
  417. __le32 d_phys_sec; /* # of physical sectors per track */
  418. __le32 d_phys_bytes; /* # of physical bytes per sector */
  419. __le32 d_unknown2; /* ? */
  420. __le32 d_unknown3; /* ? */
  421. __le32 d_pad[8]; /* pad */
  422. struct unixware_vtoc {
  423. __le32 v_magic; /* the magic number */
  424. __le32 v_version; /* version number */
  425. char v_name[8]; /* volume name */
  426. __le16 v_nslices; /* # of slices */
  427. __le16 v_unknown1; /* ? */
  428. __le32 v_reserved[10]; /* reserved */
  429. struct unixware_slice
  430. v_slice[UNIXWARE_NUMSLICE]; /* slice headers */
  431. } vtoc;
  432. }; /* 408 */
  433. #endif /* CONFIG_UNIXWARE_DISKLABEL */
  434. #ifdef CONFIG_MINIX_SUBPARTITION
  435. # define MINIX_NR_SUBPARTITIONS 4
  436. #endif /* CONFIG_MINIX_SUBPARTITION */
  437. #define ADDPART_FLAG_NONE 0
  438. #define ADDPART_FLAG_RAID 1
  439. #define ADDPART_FLAG_WHOLEDISK 2
  440. extern int blk_alloc_devt(struct hd_struct *part, dev_t *devt);
  441. extern void blk_free_devt(dev_t devt);
  442. extern dev_t blk_lookup_devt(const char *name, int partno);
  443. extern char *disk_name (struct gendisk *hd, int partno, char *buf);
  444. extern int disk_expand_part_tbl(struct gendisk *disk, int target);
  445. extern int rescan_partitions(struct gendisk *disk, struct block_device *bdev);
  446. extern struct hd_struct * __must_check add_partition(struct gendisk *disk,
  447. int partno, sector_t start,
  448. sector_t len, int flags);
  449. extern void delete_partition(struct gendisk *, int);
  450. extern void printk_all_partitions(void);
  451. extern struct gendisk *alloc_disk_node(int minors, int node_id);
  452. extern struct gendisk *alloc_disk(int minors);
  453. extern struct kobject *get_disk(struct gendisk *disk);
  454. extern void put_disk(struct gendisk *disk);
  455. extern void blk_register_region(dev_t devt, unsigned long range,
  456. struct module *module,
  457. struct kobject *(*probe)(dev_t, int *, void *),
  458. int (*lock)(dev_t, void *),
  459. void *data);
  460. extern void blk_unregister_region(dev_t devt, unsigned long range);
  461. extern ssize_t part_size_show(struct device *dev,
  462. struct device_attribute *attr, char *buf);
  463. extern ssize_t part_stat_show(struct device *dev,
  464. struct device_attribute *attr, char *buf);
  465. #ifdef CONFIG_FAIL_MAKE_REQUEST
  466. extern ssize_t part_fail_show(struct device *dev,
  467. struct device_attribute *attr, char *buf);
  468. extern ssize_t part_fail_store(struct device *dev,
  469. struct device_attribute *attr,
  470. const char *buf, size_t count);
  471. #endif /* CONFIG_FAIL_MAKE_REQUEST */
  472. #else /* CONFIG_BLOCK */
  473. static inline void printk_all_partitions(void) { }
  474. static inline dev_t blk_lookup_devt(const char *name, int partno)
  475. {
  476. dev_t devt = MKDEV(0, 0);
  477. return devt;
  478. }
  479. #endif /* CONFIG_BLOCK */
  480. #endif /* _LINUX_GENHD_H */