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