blkdev.h 37 KB

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  1. #ifndef _LINUX_BLKDEV_H
  2. #define _LINUX_BLKDEV_H
  3. #ifdef CONFIG_BLOCK
  4. #include <linux/sched.h>
  5. #include <linux/major.h>
  6. #include <linux/genhd.h>
  7. #include <linux/list.h>
  8. #include <linux/timer.h>
  9. #include <linux/workqueue.h>
  10. #include <linux/pagemap.h>
  11. #include <linux/backing-dev.h>
  12. #include <linux/wait.h>
  13. #include <linux/mempool.h>
  14. #include <linux/bio.h>
  15. #include <linux/module.h>
  16. #include <linux/stringify.h>
  17. #include <linux/gfp.h>
  18. #include <linux/bsg.h>
  19. #include <linux/smp.h>
  20. #include <asm/scatterlist.h>
  21. struct scsi_ioctl_command;
  22. struct request_queue;
  23. struct elevator_queue;
  24. struct request_pm_state;
  25. struct blk_trace;
  26. struct request;
  27. struct sg_io_hdr;
  28. #define BLKDEV_MIN_RQ 4
  29. #define BLKDEV_MAX_RQ 128 /* Default maximum */
  30. struct request;
  31. typedef void (rq_end_io_fn)(struct request *, int);
  32. struct request_list {
  33. /*
  34. * count[], starved[], and wait[] are indexed by
  35. * BLK_RW_SYNC/BLK_RW_ASYNC
  36. */
  37. int count[2];
  38. int starved[2];
  39. int elvpriv;
  40. mempool_t *rq_pool;
  41. wait_queue_head_t wait[2];
  42. };
  43. /*
  44. * request command types
  45. */
  46. enum rq_cmd_type_bits {
  47. REQ_TYPE_FS = 1, /* fs request */
  48. REQ_TYPE_BLOCK_PC, /* scsi command */
  49. REQ_TYPE_SENSE, /* sense request */
  50. REQ_TYPE_PM_SUSPEND, /* suspend request */
  51. REQ_TYPE_PM_RESUME, /* resume request */
  52. REQ_TYPE_PM_SHUTDOWN, /* shutdown request */
  53. REQ_TYPE_SPECIAL, /* driver defined type */
  54. REQ_TYPE_LINUX_BLOCK, /* generic block layer message */
  55. /*
  56. * for ATA/ATAPI devices. this really doesn't belong here, ide should
  57. * use REQ_TYPE_SPECIAL and use rq->cmd[0] with the range of driver
  58. * private REQ_LB opcodes to differentiate what type of request this is
  59. */
  60. REQ_TYPE_ATA_TASKFILE,
  61. REQ_TYPE_ATA_PC,
  62. };
  63. enum {
  64. BLK_RW_ASYNC = 0,
  65. BLK_RW_SYNC = 1,
  66. };
  67. /*
  68. * For request of type REQ_TYPE_LINUX_BLOCK, rq->cmd[0] is the opcode being
  69. * sent down (similar to how REQ_TYPE_BLOCK_PC means that ->cmd[] holds a
  70. * SCSI cdb.
  71. *
  72. * 0x00 -> 0x3f are driver private, to be used for whatever purpose they need,
  73. * typically to differentiate REQ_TYPE_SPECIAL requests.
  74. *
  75. */
  76. enum {
  77. REQ_LB_OP_EJECT = 0x40, /* eject request */
  78. REQ_LB_OP_FLUSH = 0x41, /* flush request */
  79. REQ_LB_OP_DISCARD = 0x42, /* discard sectors */
  80. };
  81. /*
  82. * request type modified bits. first two bits match BIO_RW* bits, important
  83. */
  84. enum rq_flag_bits {
  85. __REQ_RW, /* not set, read. set, write */
  86. __REQ_FAILFAST_DEV, /* no driver retries of device errors */
  87. __REQ_FAILFAST_TRANSPORT, /* no driver retries of transport errors */
  88. __REQ_FAILFAST_DRIVER, /* no driver retries of driver errors */
  89. __REQ_DISCARD, /* request to discard sectors */
  90. __REQ_SORTED, /* elevator knows about this request */
  91. __REQ_SOFTBARRIER, /* may not be passed by ioscheduler */
  92. __REQ_HARDBARRIER, /* may not be passed by drive either */
  93. __REQ_FUA, /* forced unit access */
  94. __REQ_NOMERGE, /* don't touch this for merging */
  95. __REQ_STARTED, /* drive already may have started this one */
  96. __REQ_DONTPREP, /* don't call prep for this one */
  97. __REQ_QUEUED, /* uses queueing */
  98. __REQ_ELVPRIV, /* elevator private data attached */
  99. __REQ_FAILED, /* set if the request failed */
  100. __REQ_QUIET, /* don't worry about errors */
  101. __REQ_PREEMPT, /* set for "ide_preempt" requests */
  102. __REQ_ORDERED_COLOR, /* is before or after barrier */
  103. __REQ_RW_SYNC, /* request is sync (sync write or read) */
  104. __REQ_ALLOCED, /* request came from our alloc pool */
  105. __REQ_RW_META, /* metadata io request */
  106. __REQ_COPY_USER, /* contains copies of user pages */
  107. __REQ_INTEGRITY, /* integrity metadata has been remapped */
  108. __REQ_NOIDLE, /* Don't anticipate more IO after this one */
  109. __REQ_IO_STAT, /* account I/O stat */
  110. __REQ_NR_BITS, /* stops here */
  111. };
  112. #define REQ_RW (1 << __REQ_RW)
  113. #define REQ_FAILFAST_DEV (1 << __REQ_FAILFAST_DEV)
  114. #define REQ_FAILFAST_TRANSPORT (1 << __REQ_FAILFAST_TRANSPORT)
  115. #define REQ_FAILFAST_DRIVER (1 << __REQ_FAILFAST_DRIVER)
  116. #define REQ_DISCARD (1 << __REQ_DISCARD)
  117. #define REQ_SORTED (1 << __REQ_SORTED)
  118. #define REQ_SOFTBARRIER (1 << __REQ_SOFTBARRIER)
  119. #define REQ_HARDBARRIER (1 << __REQ_HARDBARRIER)
  120. #define REQ_FUA (1 << __REQ_FUA)
  121. #define REQ_NOMERGE (1 << __REQ_NOMERGE)
  122. #define REQ_STARTED (1 << __REQ_STARTED)
  123. #define REQ_DONTPREP (1 << __REQ_DONTPREP)
  124. #define REQ_QUEUED (1 << __REQ_QUEUED)
  125. #define REQ_ELVPRIV (1 << __REQ_ELVPRIV)
  126. #define REQ_FAILED (1 << __REQ_FAILED)
  127. #define REQ_QUIET (1 << __REQ_QUIET)
  128. #define REQ_PREEMPT (1 << __REQ_PREEMPT)
  129. #define REQ_ORDERED_COLOR (1 << __REQ_ORDERED_COLOR)
  130. #define REQ_RW_SYNC (1 << __REQ_RW_SYNC)
  131. #define REQ_ALLOCED (1 << __REQ_ALLOCED)
  132. #define REQ_RW_META (1 << __REQ_RW_META)
  133. #define REQ_COPY_USER (1 << __REQ_COPY_USER)
  134. #define REQ_INTEGRITY (1 << __REQ_INTEGRITY)
  135. #define REQ_NOIDLE (1 << __REQ_NOIDLE)
  136. #define REQ_IO_STAT (1 << __REQ_IO_STAT)
  137. #define BLK_MAX_CDB 16
  138. /*
  139. * try to put the fields that are referenced together in the same cacheline.
  140. * if you modify this structure, be sure to check block/blk-core.c:rq_init()
  141. * as well!
  142. */
  143. struct request {
  144. struct list_head queuelist;
  145. struct call_single_data csd;
  146. int cpu;
  147. struct request_queue *q;
  148. unsigned int cmd_flags;
  149. enum rq_cmd_type_bits cmd_type;
  150. unsigned long atomic_flags;
  151. /* Maintain bio traversal state for part by part I/O submission.
  152. * hard_* are block layer internals, no driver should touch them!
  153. */
  154. sector_t sector; /* next sector to submit */
  155. sector_t hard_sector; /* next sector to complete */
  156. unsigned long nr_sectors; /* no. of sectors left to submit */
  157. unsigned long hard_nr_sectors; /* no. of sectors left to complete */
  158. /* no. of sectors left to submit in the current segment */
  159. unsigned int current_nr_sectors;
  160. /* no. of sectors left to complete in the current segment */
  161. unsigned int hard_cur_sectors;
  162. struct bio *bio;
  163. struct bio *biotail;
  164. struct hlist_node hash; /* merge hash */
  165. /*
  166. * The rb_node is only used inside the io scheduler, requests
  167. * are pruned when moved to the dispatch queue. So let the
  168. * completion_data share space with the rb_node.
  169. */
  170. union {
  171. struct rb_node rb_node; /* sort/lookup */
  172. void *completion_data;
  173. };
  174. /*
  175. * two pointers are available for the IO schedulers, if they need
  176. * more they have to dynamically allocate it.
  177. */
  178. void *elevator_private;
  179. void *elevator_private2;
  180. struct gendisk *rq_disk;
  181. unsigned long start_time;
  182. /* Number of scatter-gather DMA addr+len pairs after
  183. * physical address coalescing is performed.
  184. */
  185. unsigned short nr_phys_segments;
  186. unsigned short ioprio;
  187. void *special; /* opaque pointer available for LLD use */
  188. char *buffer; /* kaddr of the current segment if available */
  189. int tag;
  190. int errors;
  191. int ref_count;
  192. /*
  193. * when request is used as a packet command carrier
  194. */
  195. unsigned short cmd_len;
  196. unsigned char __cmd[BLK_MAX_CDB];
  197. unsigned char *cmd;
  198. unsigned int data_len;
  199. unsigned int extra_len; /* length of alignment and padding */
  200. unsigned int sense_len;
  201. void *sense;
  202. unsigned long deadline;
  203. struct list_head timeout_list;
  204. unsigned int timeout;
  205. int retries;
  206. /*
  207. * completion callback.
  208. */
  209. rq_end_io_fn *end_io;
  210. void *end_io_data;
  211. /* for bidi */
  212. struct request *next_rq;
  213. };
  214. static inline unsigned short req_get_ioprio(struct request *req)
  215. {
  216. return req->ioprio;
  217. }
  218. /*
  219. * State information carried for REQ_TYPE_PM_SUSPEND and REQ_TYPE_PM_RESUME
  220. * requests. Some step values could eventually be made generic.
  221. */
  222. struct request_pm_state
  223. {
  224. /* PM state machine step value, currently driver specific */
  225. int pm_step;
  226. /* requested PM state value (S1, S2, S3, S4, ...) */
  227. u32 pm_state;
  228. void* data; /* for driver use */
  229. };
  230. #include <linux/elevator.h>
  231. typedef void (request_fn_proc) (struct request_queue *q);
  232. typedef int (make_request_fn) (struct request_queue *q, struct bio *bio);
  233. typedef int (prep_rq_fn) (struct request_queue *, struct request *);
  234. typedef void (unplug_fn) (struct request_queue *);
  235. typedef int (prepare_discard_fn) (struct request_queue *, struct request *);
  236. struct bio_vec;
  237. struct bvec_merge_data {
  238. struct block_device *bi_bdev;
  239. sector_t bi_sector;
  240. unsigned bi_size;
  241. unsigned long bi_rw;
  242. };
  243. typedef int (merge_bvec_fn) (struct request_queue *, struct bvec_merge_data *,
  244. struct bio_vec *);
  245. typedef void (prepare_flush_fn) (struct request_queue *, struct request *);
  246. typedef void (softirq_done_fn)(struct request *);
  247. typedef int (dma_drain_needed_fn)(struct request *);
  248. typedef int (lld_busy_fn) (struct request_queue *q);
  249. enum blk_eh_timer_return {
  250. BLK_EH_NOT_HANDLED,
  251. BLK_EH_HANDLED,
  252. BLK_EH_RESET_TIMER,
  253. };
  254. typedef enum blk_eh_timer_return (rq_timed_out_fn)(struct request *);
  255. enum blk_queue_state {
  256. Queue_down,
  257. Queue_up,
  258. };
  259. struct blk_queue_tag {
  260. struct request **tag_index; /* map of busy tags */
  261. unsigned long *tag_map; /* bit map of free/busy tags */
  262. int busy; /* current depth */
  263. int max_depth; /* what we will send to device */
  264. int real_max_depth; /* what the array can hold */
  265. atomic_t refcnt; /* map can be shared */
  266. };
  267. #define BLK_SCSI_MAX_CMDS (256)
  268. #define BLK_SCSI_CMD_PER_LONG (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
  269. struct blk_cmd_filter {
  270. unsigned long read_ok[BLK_SCSI_CMD_PER_LONG];
  271. unsigned long write_ok[BLK_SCSI_CMD_PER_LONG];
  272. struct kobject kobj;
  273. };
  274. struct request_queue
  275. {
  276. /*
  277. * Together with queue_head for cacheline sharing
  278. */
  279. struct list_head queue_head;
  280. struct request *last_merge;
  281. struct elevator_queue *elevator;
  282. /*
  283. * the queue request freelist, one for reads and one for writes
  284. */
  285. struct request_list rq;
  286. request_fn_proc *request_fn;
  287. make_request_fn *make_request_fn;
  288. prep_rq_fn *prep_rq_fn;
  289. unplug_fn *unplug_fn;
  290. prepare_discard_fn *prepare_discard_fn;
  291. merge_bvec_fn *merge_bvec_fn;
  292. prepare_flush_fn *prepare_flush_fn;
  293. softirq_done_fn *softirq_done_fn;
  294. rq_timed_out_fn *rq_timed_out_fn;
  295. dma_drain_needed_fn *dma_drain_needed;
  296. lld_busy_fn *lld_busy_fn;
  297. /*
  298. * Dispatch queue sorting
  299. */
  300. sector_t end_sector;
  301. struct request *boundary_rq;
  302. /*
  303. * Auto-unplugging state
  304. */
  305. struct timer_list unplug_timer;
  306. int unplug_thresh; /* After this many requests */
  307. unsigned long unplug_delay; /* After this many jiffies */
  308. struct work_struct unplug_work;
  309. struct backing_dev_info backing_dev_info;
  310. /*
  311. * The queue owner gets to use this for whatever they like.
  312. * ll_rw_blk doesn't touch it.
  313. */
  314. void *queuedata;
  315. /*
  316. * queue needs bounce pages for pages above this limit
  317. */
  318. unsigned long bounce_pfn;
  319. gfp_t bounce_gfp;
  320. /*
  321. * various queue flags, see QUEUE_* below
  322. */
  323. unsigned long queue_flags;
  324. /*
  325. * protects queue structures from reentrancy. ->__queue_lock should
  326. * _never_ be used directly, it is queue private. always use
  327. * ->queue_lock.
  328. */
  329. spinlock_t __queue_lock;
  330. spinlock_t *queue_lock;
  331. /*
  332. * queue kobject
  333. */
  334. struct kobject kobj;
  335. /*
  336. * queue settings
  337. */
  338. unsigned long nr_requests; /* Max # of requests */
  339. unsigned int nr_congestion_on;
  340. unsigned int nr_congestion_off;
  341. unsigned int nr_batching;
  342. unsigned int max_sectors;
  343. unsigned int max_hw_sectors;
  344. unsigned short max_phys_segments;
  345. unsigned short max_hw_segments;
  346. unsigned short hardsect_size;
  347. unsigned int max_segment_size;
  348. unsigned long seg_boundary_mask;
  349. void *dma_drain_buffer;
  350. unsigned int dma_drain_size;
  351. unsigned int dma_pad_mask;
  352. unsigned int dma_alignment;
  353. struct blk_queue_tag *queue_tags;
  354. struct list_head tag_busy_list;
  355. unsigned int nr_sorted;
  356. unsigned int in_flight;
  357. unsigned int rq_timeout;
  358. struct timer_list timeout;
  359. struct list_head timeout_list;
  360. /*
  361. * sg stuff
  362. */
  363. unsigned int sg_timeout;
  364. unsigned int sg_reserved_size;
  365. int node;
  366. #ifdef CONFIG_BLK_DEV_IO_TRACE
  367. struct blk_trace *blk_trace;
  368. #endif
  369. /*
  370. * reserved for flush operations
  371. */
  372. unsigned int ordered, next_ordered, ordseq;
  373. int orderr, ordcolor;
  374. struct request pre_flush_rq, bar_rq, post_flush_rq;
  375. struct request *orig_bar_rq;
  376. struct mutex sysfs_lock;
  377. #if defined(CONFIG_BLK_DEV_BSG)
  378. struct bsg_class_device bsg_dev;
  379. #endif
  380. struct blk_cmd_filter cmd_filter;
  381. };
  382. #define QUEUE_FLAG_CLUSTER 0 /* cluster several segments into 1 */
  383. #define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */
  384. #define QUEUE_FLAG_STOPPED 2 /* queue is stopped */
  385. #define QUEUE_FLAG_SYNCFULL 3 /* read queue has been filled */
  386. #define QUEUE_FLAG_ASYNCFULL 4 /* write queue has been filled */
  387. #define QUEUE_FLAG_DEAD 5 /* queue being torn down */
  388. #define QUEUE_FLAG_REENTER 6 /* Re-entrancy avoidance */
  389. #define QUEUE_FLAG_PLUGGED 7 /* queue is plugged */
  390. #define QUEUE_FLAG_ELVSWITCH 8 /* don't use elevator, just do FIFO */
  391. #define QUEUE_FLAG_BIDI 9 /* queue supports bidi requests */
  392. #define QUEUE_FLAG_NOMERGES 10 /* disable merge attempts */
  393. #define QUEUE_FLAG_SAME_COMP 11 /* force complete on same CPU */
  394. #define QUEUE_FLAG_FAIL_IO 12 /* fake timeout */
  395. #define QUEUE_FLAG_STACKABLE 13 /* supports request stacking */
  396. #define QUEUE_FLAG_NONROT 14 /* non-rotational device (SSD) */
  397. #define QUEUE_FLAG_VIRT QUEUE_FLAG_NONROT /* paravirt device */
  398. #define QUEUE_FLAG_IO_STAT 15 /* do IO stats */
  399. #define QUEUE_FLAG_DEFAULT ((1 << QUEUE_FLAG_IO_STAT) | \
  400. (1 << QUEUE_FLAG_CLUSTER) | \
  401. (1 << QUEUE_FLAG_STACKABLE))
  402. static inline int queue_is_locked(struct request_queue *q)
  403. {
  404. #ifdef CONFIG_SMP
  405. spinlock_t *lock = q->queue_lock;
  406. return lock && spin_is_locked(lock);
  407. #else
  408. return 1;
  409. #endif
  410. }
  411. static inline void queue_flag_set_unlocked(unsigned int flag,
  412. struct request_queue *q)
  413. {
  414. __set_bit(flag, &q->queue_flags);
  415. }
  416. static inline int queue_flag_test_and_clear(unsigned int flag,
  417. struct request_queue *q)
  418. {
  419. WARN_ON_ONCE(!queue_is_locked(q));
  420. if (test_bit(flag, &q->queue_flags)) {
  421. __clear_bit(flag, &q->queue_flags);
  422. return 1;
  423. }
  424. return 0;
  425. }
  426. static inline int queue_flag_test_and_set(unsigned int flag,
  427. struct request_queue *q)
  428. {
  429. WARN_ON_ONCE(!queue_is_locked(q));
  430. if (!test_bit(flag, &q->queue_flags)) {
  431. __set_bit(flag, &q->queue_flags);
  432. return 0;
  433. }
  434. return 1;
  435. }
  436. static inline void queue_flag_set(unsigned int flag, struct request_queue *q)
  437. {
  438. WARN_ON_ONCE(!queue_is_locked(q));
  439. __set_bit(flag, &q->queue_flags);
  440. }
  441. static inline void queue_flag_clear_unlocked(unsigned int flag,
  442. struct request_queue *q)
  443. {
  444. __clear_bit(flag, &q->queue_flags);
  445. }
  446. static inline void queue_flag_clear(unsigned int flag, struct request_queue *q)
  447. {
  448. WARN_ON_ONCE(!queue_is_locked(q));
  449. __clear_bit(flag, &q->queue_flags);
  450. }
  451. enum {
  452. /*
  453. * Hardbarrier is supported with one of the following methods.
  454. *
  455. * NONE : hardbarrier unsupported
  456. * DRAIN : ordering by draining is enough
  457. * DRAIN_FLUSH : ordering by draining w/ pre and post flushes
  458. * DRAIN_FUA : ordering by draining w/ pre flush and FUA write
  459. * TAG : ordering by tag is enough
  460. * TAG_FLUSH : ordering by tag w/ pre and post flushes
  461. * TAG_FUA : ordering by tag w/ pre flush and FUA write
  462. */
  463. QUEUE_ORDERED_BY_DRAIN = 0x01,
  464. QUEUE_ORDERED_BY_TAG = 0x02,
  465. QUEUE_ORDERED_DO_PREFLUSH = 0x10,
  466. QUEUE_ORDERED_DO_BAR = 0x20,
  467. QUEUE_ORDERED_DO_POSTFLUSH = 0x40,
  468. QUEUE_ORDERED_DO_FUA = 0x80,
  469. QUEUE_ORDERED_NONE = 0x00,
  470. QUEUE_ORDERED_DRAIN = QUEUE_ORDERED_BY_DRAIN |
  471. QUEUE_ORDERED_DO_BAR,
  472. QUEUE_ORDERED_DRAIN_FLUSH = QUEUE_ORDERED_DRAIN |
  473. QUEUE_ORDERED_DO_PREFLUSH |
  474. QUEUE_ORDERED_DO_POSTFLUSH,
  475. QUEUE_ORDERED_DRAIN_FUA = QUEUE_ORDERED_DRAIN |
  476. QUEUE_ORDERED_DO_PREFLUSH |
  477. QUEUE_ORDERED_DO_FUA,
  478. QUEUE_ORDERED_TAG = QUEUE_ORDERED_BY_TAG |
  479. QUEUE_ORDERED_DO_BAR,
  480. QUEUE_ORDERED_TAG_FLUSH = QUEUE_ORDERED_TAG |
  481. QUEUE_ORDERED_DO_PREFLUSH |
  482. QUEUE_ORDERED_DO_POSTFLUSH,
  483. QUEUE_ORDERED_TAG_FUA = QUEUE_ORDERED_TAG |
  484. QUEUE_ORDERED_DO_PREFLUSH |
  485. QUEUE_ORDERED_DO_FUA,
  486. /*
  487. * Ordered operation sequence
  488. */
  489. QUEUE_ORDSEQ_STARTED = 0x01, /* flushing in progress */
  490. QUEUE_ORDSEQ_DRAIN = 0x02, /* waiting for the queue to be drained */
  491. QUEUE_ORDSEQ_PREFLUSH = 0x04, /* pre-flushing in progress */
  492. QUEUE_ORDSEQ_BAR = 0x08, /* original barrier req in progress */
  493. QUEUE_ORDSEQ_POSTFLUSH = 0x10, /* post-flushing in progress */
  494. QUEUE_ORDSEQ_DONE = 0x20,
  495. };
  496. #define blk_queue_plugged(q) test_bit(QUEUE_FLAG_PLUGGED, &(q)->queue_flags)
  497. #define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags)
  498. #define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)
  499. #define blk_queue_nomerges(q) test_bit(QUEUE_FLAG_NOMERGES, &(q)->queue_flags)
  500. #define blk_queue_nonrot(q) test_bit(QUEUE_FLAG_NONROT, &(q)->queue_flags)
  501. #define blk_queue_io_stat(q) test_bit(QUEUE_FLAG_IO_STAT, &(q)->queue_flags)
  502. #define blk_queue_flushing(q) ((q)->ordseq)
  503. #define blk_queue_stackable(q) \
  504. test_bit(QUEUE_FLAG_STACKABLE, &(q)->queue_flags)
  505. #define blk_fs_request(rq) ((rq)->cmd_type == REQ_TYPE_FS)
  506. #define blk_pc_request(rq) ((rq)->cmd_type == REQ_TYPE_BLOCK_PC)
  507. #define blk_special_request(rq) ((rq)->cmd_type == REQ_TYPE_SPECIAL)
  508. #define blk_sense_request(rq) ((rq)->cmd_type == REQ_TYPE_SENSE)
  509. #define blk_failfast_dev(rq) ((rq)->cmd_flags & REQ_FAILFAST_DEV)
  510. #define blk_failfast_transport(rq) ((rq)->cmd_flags & REQ_FAILFAST_TRANSPORT)
  511. #define blk_failfast_driver(rq) ((rq)->cmd_flags & REQ_FAILFAST_DRIVER)
  512. #define blk_noretry_request(rq) (blk_failfast_dev(rq) || \
  513. blk_failfast_transport(rq) || \
  514. blk_failfast_driver(rq))
  515. #define blk_rq_started(rq) ((rq)->cmd_flags & REQ_STARTED)
  516. #define blk_rq_io_stat(rq) ((rq)->cmd_flags & REQ_IO_STAT)
  517. #define blk_account_rq(rq) (blk_rq_started(rq) && (blk_fs_request(rq) || blk_discard_rq(rq)))
  518. #define blk_pm_suspend_request(rq) ((rq)->cmd_type == REQ_TYPE_PM_SUSPEND)
  519. #define blk_pm_resume_request(rq) ((rq)->cmd_type == REQ_TYPE_PM_RESUME)
  520. #define blk_pm_request(rq) \
  521. (blk_pm_suspend_request(rq) || blk_pm_resume_request(rq))
  522. #define blk_rq_cpu_valid(rq) ((rq)->cpu != -1)
  523. #define blk_sorted_rq(rq) ((rq)->cmd_flags & REQ_SORTED)
  524. #define blk_barrier_rq(rq) ((rq)->cmd_flags & REQ_HARDBARRIER)
  525. #define blk_fua_rq(rq) ((rq)->cmd_flags & REQ_FUA)
  526. #define blk_discard_rq(rq) ((rq)->cmd_flags & REQ_DISCARD)
  527. #define blk_bidi_rq(rq) ((rq)->next_rq != NULL)
  528. /* rq->queuelist of dequeued request must be list_empty() */
  529. #define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist))
  530. #define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist)
  531. #define rq_data_dir(rq) ((rq)->cmd_flags & 1)
  532. /*
  533. * We regard a request as sync, if either a read or a sync write
  534. */
  535. static inline bool rw_is_sync(unsigned int rw_flags)
  536. {
  537. return !(rw_flags & REQ_RW) || (rw_flags & REQ_RW_SYNC);
  538. }
  539. static inline bool rq_is_sync(struct request *rq)
  540. {
  541. return rw_is_sync(rq->cmd_flags);
  542. }
  543. #define rq_is_meta(rq) ((rq)->cmd_flags & REQ_RW_META)
  544. #define rq_noidle(rq) ((rq)->cmd_flags & REQ_NOIDLE)
  545. static inline int blk_queue_full(struct request_queue *q, int sync)
  546. {
  547. if (sync)
  548. return test_bit(QUEUE_FLAG_SYNCFULL, &q->queue_flags);
  549. return test_bit(QUEUE_FLAG_ASYNCFULL, &q->queue_flags);
  550. }
  551. static inline void blk_set_queue_full(struct request_queue *q, int sync)
  552. {
  553. if (sync)
  554. queue_flag_set(QUEUE_FLAG_SYNCFULL, q);
  555. else
  556. queue_flag_set(QUEUE_FLAG_ASYNCFULL, q);
  557. }
  558. static inline void blk_clear_queue_full(struct request_queue *q, int sync)
  559. {
  560. if (sync)
  561. queue_flag_clear(QUEUE_FLAG_SYNCFULL, q);
  562. else
  563. queue_flag_clear(QUEUE_FLAG_ASYNCFULL, q);
  564. }
  565. /*
  566. * mergeable request must not have _NOMERGE or _BARRIER bit set, nor may
  567. * it already be started by driver.
  568. */
  569. #define RQ_NOMERGE_FLAGS \
  570. (REQ_NOMERGE | REQ_STARTED | REQ_HARDBARRIER | REQ_SOFTBARRIER)
  571. #define rq_mergeable(rq) \
  572. (!((rq)->cmd_flags & RQ_NOMERGE_FLAGS) && \
  573. (blk_discard_rq(rq) || blk_fs_request((rq))))
  574. /*
  575. * q->prep_rq_fn return values
  576. */
  577. #define BLKPREP_OK 0 /* serve it */
  578. #define BLKPREP_KILL 1 /* fatal error, kill */
  579. #define BLKPREP_DEFER 2 /* leave on queue */
  580. extern unsigned long blk_max_low_pfn, blk_max_pfn;
  581. /*
  582. * standard bounce addresses:
  583. *
  584. * BLK_BOUNCE_HIGH : bounce all highmem pages
  585. * BLK_BOUNCE_ANY : don't bounce anything
  586. * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary
  587. */
  588. #if BITS_PER_LONG == 32
  589. #define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT)
  590. #else
  591. #define BLK_BOUNCE_HIGH -1ULL
  592. #endif
  593. #define BLK_BOUNCE_ANY (-1ULL)
  594. #define BLK_BOUNCE_ISA (ISA_DMA_THRESHOLD)
  595. /*
  596. * default timeout for SG_IO if none specified
  597. */
  598. #define BLK_DEFAULT_SG_TIMEOUT (60 * HZ)
  599. #define BLK_MIN_SG_TIMEOUT (7 * HZ)
  600. #ifdef CONFIG_BOUNCE
  601. extern int init_emergency_isa_pool(void);
  602. extern void blk_queue_bounce(struct request_queue *q, struct bio **bio);
  603. #else
  604. static inline int init_emergency_isa_pool(void)
  605. {
  606. return 0;
  607. }
  608. static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio)
  609. {
  610. }
  611. #endif /* CONFIG_MMU */
  612. struct rq_map_data {
  613. struct page **pages;
  614. int page_order;
  615. int nr_entries;
  616. unsigned long offset;
  617. int null_mapped;
  618. };
  619. struct req_iterator {
  620. int i;
  621. struct bio *bio;
  622. };
  623. /* This should not be used directly - use rq_for_each_segment */
  624. #define for_each_bio(_bio) \
  625. for (; _bio; _bio = _bio->bi_next)
  626. #define __rq_for_each_bio(_bio, rq) \
  627. if ((rq->bio)) \
  628. for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next)
  629. #define rq_for_each_segment(bvl, _rq, _iter) \
  630. __rq_for_each_bio(_iter.bio, _rq) \
  631. bio_for_each_segment(bvl, _iter.bio, _iter.i)
  632. #define rq_iter_last(rq, _iter) \
  633. (_iter.bio->bi_next == NULL && _iter.i == _iter.bio->bi_vcnt-1)
  634. extern int blk_register_queue(struct gendisk *disk);
  635. extern void blk_unregister_queue(struct gendisk *disk);
  636. extern void register_disk(struct gendisk *dev);
  637. extern void generic_make_request(struct bio *bio);
  638. extern void blk_rq_init(struct request_queue *q, struct request *rq);
  639. extern void blk_put_request(struct request *);
  640. extern void __blk_put_request(struct request_queue *, struct request *);
  641. extern struct request *blk_get_request(struct request_queue *, int, gfp_t);
  642. extern void blk_insert_request(struct request_queue *, struct request *, int, void *);
  643. extern void blk_requeue_request(struct request_queue *, struct request *);
  644. extern int blk_rq_check_limits(struct request_queue *q, struct request *rq);
  645. extern int blk_lld_busy(struct request_queue *q);
  646. extern int blk_insert_cloned_request(struct request_queue *q,
  647. struct request *rq);
  648. extern void blk_plug_device(struct request_queue *);
  649. extern void blk_plug_device_unlocked(struct request_queue *);
  650. extern int blk_remove_plug(struct request_queue *);
  651. extern void blk_recount_segments(struct request_queue *, struct bio *);
  652. extern int scsi_cmd_ioctl(struct request_queue *, struct gendisk *, fmode_t,
  653. unsigned int, void __user *);
  654. extern int sg_scsi_ioctl(struct request_queue *, struct gendisk *, fmode_t,
  655. struct scsi_ioctl_command __user *);
  656. /*
  657. * Temporary export, until SCSI gets fixed up.
  658. */
  659. extern int blk_rq_append_bio(struct request_queue *q, struct request *rq,
  660. struct bio *bio);
  661. /*
  662. * A queue has just exitted congestion. Note this in the global counter of
  663. * congested queues, and wake up anyone who was waiting for requests to be
  664. * put back.
  665. */
  666. static inline void blk_clear_queue_congested(struct request_queue *q, int rw)
  667. {
  668. clear_bdi_congested(&q->backing_dev_info, rw);
  669. }
  670. /*
  671. * A queue has just entered congestion. Flag that in the queue's VM-visible
  672. * state flags and increment the global gounter of congested queues.
  673. */
  674. static inline void blk_set_queue_congested(struct request_queue *q, int rw)
  675. {
  676. set_bdi_congested(&q->backing_dev_info, rw);
  677. }
  678. extern void blk_start_queue(struct request_queue *q);
  679. extern void blk_stop_queue(struct request_queue *q);
  680. extern void blk_sync_queue(struct request_queue *q);
  681. extern void __blk_stop_queue(struct request_queue *q);
  682. extern void __blk_run_queue(struct request_queue *);
  683. extern void blk_run_queue(struct request_queue *);
  684. extern int blk_rq_map_user(struct request_queue *, struct request *,
  685. struct rq_map_data *, void __user *, unsigned long,
  686. gfp_t);
  687. extern int blk_rq_unmap_user(struct bio *);
  688. extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t);
  689. extern int blk_rq_map_user_iov(struct request_queue *, struct request *,
  690. struct rq_map_data *, struct sg_iovec *, int,
  691. unsigned int, gfp_t);
  692. extern int blk_execute_rq(struct request_queue *, struct gendisk *,
  693. struct request *, int);
  694. extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *,
  695. struct request *, int, rq_end_io_fn *);
  696. extern void blk_unplug(struct request_queue *q);
  697. static inline struct request_queue *bdev_get_queue(struct block_device *bdev)
  698. {
  699. return bdev->bd_disk->queue;
  700. }
  701. static inline void blk_run_backing_dev(struct backing_dev_info *bdi,
  702. struct page *page)
  703. {
  704. if (bdi && bdi->unplug_io_fn)
  705. bdi->unplug_io_fn(bdi, page);
  706. }
  707. static inline void blk_run_address_space(struct address_space *mapping)
  708. {
  709. if (mapping)
  710. blk_run_backing_dev(mapping->backing_dev_info, NULL);
  711. }
  712. extern void blkdev_dequeue_request(struct request *req);
  713. /*
  714. * blk_end_request() takes bytes instead of sectors as a complete size.
  715. * blk_rq_bytes() returns bytes left to complete in the entire request.
  716. * blk_rq_cur_bytes() returns bytes left to complete in the current segment.
  717. */
  718. extern unsigned int blk_rq_bytes(struct request *rq);
  719. extern unsigned int blk_rq_cur_bytes(struct request *rq);
  720. /*
  721. * Request completion related functions.
  722. *
  723. * blk_update_request() completes given number of bytes and updates
  724. * the request without completing it.
  725. *
  726. * blk_end_request() and friends. __blk_end_request() must be called
  727. * with the request queue spinlock acquired.
  728. *
  729. * Several drivers define their own end_request and call
  730. * blk_end_request() for parts of the original function.
  731. * This prevents code duplication in drivers.
  732. */
  733. extern bool blk_update_request(struct request *rq, int error,
  734. unsigned int nr_bytes);
  735. extern bool blk_end_bidi_request(struct request *rq, int error,
  736. unsigned int nr_bytes,
  737. unsigned int bidi_bytes);
  738. extern bool __blk_end_bidi_request(struct request *rq, int error,
  739. unsigned int nr_bytes,
  740. unsigned int bidi_bytes);
  741. /**
  742. * blk_end_request - Helper function for drivers to complete the request.
  743. * @rq: the request being processed
  744. * @error: %0 for success, < %0 for error
  745. * @nr_bytes: number of bytes to complete
  746. *
  747. * Description:
  748. * Ends I/O on a number of bytes attached to @rq.
  749. * If @rq has leftover, sets it up for the next range of segments.
  750. *
  751. * Return:
  752. * %false - we are done with this request
  753. * %true - still buffers pending for this request
  754. **/
  755. static inline bool blk_end_request(struct request *rq, int error,
  756. unsigned int nr_bytes)
  757. {
  758. return blk_end_bidi_request(rq, error, nr_bytes, 0);
  759. }
  760. /**
  761. * blk_end_request_all - Helper function for drives to finish the request.
  762. * @rq: the request to finish
  763. * @err: %0 for success, < %0 for error
  764. *
  765. * Description:
  766. * Completely finish @rq.
  767. */
  768. static inline void blk_end_request_all(struct request *rq, int error)
  769. {
  770. bool pending;
  771. pending = blk_end_request(rq, error, blk_rq_bytes(rq));
  772. BUG_ON(pending);
  773. }
  774. /**
  775. * blk_end_request_cur - Helper function to finish the current request chunk.
  776. * @rq: the request to finish the current chunk for
  777. * @err: %0 for success, < %0 for error
  778. *
  779. * Description:
  780. * Complete the current consecutively mapped chunk from @rq.
  781. *
  782. * Return:
  783. * %false - we are done with this request
  784. * %true - still buffers pending for this request
  785. */
  786. static inline bool blk_end_request_cur(struct request *rq, int error)
  787. {
  788. return blk_end_request(rq, error, rq->hard_cur_sectors << 9);
  789. }
  790. /**
  791. * __blk_end_request - Helper function for drivers to complete the request.
  792. * @rq: the request being processed
  793. * @error: %0 for success, < %0 for error
  794. * @nr_bytes: number of bytes to complete
  795. *
  796. * Description:
  797. * Must be called with queue lock held unlike blk_end_request().
  798. *
  799. * Return:
  800. * %false - we are done with this request
  801. * %true - still buffers pending for this request
  802. **/
  803. static inline bool __blk_end_request(struct request *rq, int error,
  804. unsigned int nr_bytes)
  805. {
  806. return __blk_end_bidi_request(rq, error, nr_bytes, 0);
  807. }
  808. /**
  809. * __blk_end_request_all - Helper function for drives to finish the request.
  810. * @rq: the request to finish
  811. * @err: %0 for success, < %0 for error
  812. *
  813. * Description:
  814. * Completely finish @rq. Must be called with queue lock held.
  815. */
  816. static inline void __blk_end_request_all(struct request *rq, int error)
  817. {
  818. bool pending;
  819. pending = __blk_end_request(rq, error, blk_rq_bytes(rq));
  820. BUG_ON(pending);
  821. }
  822. /**
  823. * __blk_end_request_cur - Helper function to finish the current request chunk.
  824. * @rq: the request to finish the current chunk for
  825. * @err: %0 for success, < %0 for error
  826. *
  827. * Description:
  828. * Complete the current consecutively mapped chunk from @rq. Must
  829. * be called with queue lock held.
  830. *
  831. * Return:
  832. * %false - we are done with this request
  833. * %true - still buffers pending for this request
  834. */
  835. static inline bool __blk_end_request_cur(struct request *rq, int error)
  836. {
  837. return __blk_end_request(rq, error, rq->hard_cur_sectors << 9);
  838. }
  839. extern void blk_complete_request(struct request *);
  840. extern void __blk_complete_request(struct request *);
  841. extern void blk_abort_request(struct request *);
  842. extern void blk_abort_queue(struct request_queue *);
  843. /*
  844. * Access functions for manipulating queue properties
  845. */
  846. extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn,
  847. spinlock_t *lock, int node_id);
  848. extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *);
  849. extern void blk_cleanup_queue(struct request_queue *);
  850. extern void blk_queue_make_request(struct request_queue *, make_request_fn *);
  851. extern void blk_queue_bounce_limit(struct request_queue *, u64);
  852. extern void blk_queue_max_sectors(struct request_queue *, unsigned int);
  853. extern void blk_queue_max_phys_segments(struct request_queue *, unsigned short);
  854. extern void blk_queue_max_hw_segments(struct request_queue *, unsigned short);
  855. extern void blk_queue_max_segment_size(struct request_queue *, unsigned int);
  856. extern void blk_queue_hardsect_size(struct request_queue *, unsigned short);
  857. extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b);
  858. extern void blk_queue_dma_pad(struct request_queue *, unsigned int);
  859. extern void blk_queue_update_dma_pad(struct request_queue *, unsigned int);
  860. extern int blk_queue_dma_drain(struct request_queue *q,
  861. dma_drain_needed_fn *dma_drain_needed,
  862. void *buf, unsigned int size);
  863. extern void blk_queue_lld_busy(struct request_queue *q, lld_busy_fn *fn);
  864. extern void blk_queue_segment_boundary(struct request_queue *, unsigned long);
  865. extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn);
  866. extern void blk_queue_merge_bvec(struct request_queue *, merge_bvec_fn *);
  867. extern void blk_queue_dma_alignment(struct request_queue *, int);
  868. extern void blk_queue_update_dma_alignment(struct request_queue *, int);
  869. extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *);
  870. extern void blk_queue_set_discard(struct request_queue *, prepare_discard_fn *);
  871. extern void blk_queue_rq_timed_out(struct request_queue *, rq_timed_out_fn *);
  872. extern void blk_queue_rq_timeout(struct request_queue *, unsigned int);
  873. extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev);
  874. extern int blk_queue_ordered(struct request_queue *, unsigned, prepare_flush_fn *);
  875. extern bool blk_do_ordered(struct request_queue *, struct request **);
  876. extern unsigned blk_ordered_cur_seq(struct request_queue *);
  877. extern unsigned blk_ordered_req_seq(struct request *);
  878. extern bool blk_ordered_complete_seq(struct request_queue *, unsigned, int);
  879. extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *);
  880. extern void blk_dump_rq_flags(struct request *, char *);
  881. extern void generic_unplug_device(struct request_queue *);
  882. extern long nr_blockdev_pages(void);
  883. int blk_get_queue(struct request_queue *);
  884. struct request_queue *blk_alloc_queue(gfp_t);
  885. struct request_queue *blk_alloc_queue_node(gfp_t, int);
  886. extern void blk_put_queue(struct request_queue *);
  887. /*
  888. * tag stuff
  889. */
  890. #define blk_rq_tagged(rq) ((rq)->cmd_flags & REQ_QUEUED)
  891. extern int blk_queue_start_tag(struct request_queue *, struct request *);
  892. extern struct request *blk_queue_find_tag(struct request_queue *, int);
  893. extern void blk_queue_end_tag(struct request_queue *, struct request *);
  894. extern int blk_queue_init_tags(struct request_queue *, int, struct blk_queue_tag *);
  895. extern void blk_queue_free_tags(struct request_queue *);
  896. extern int blk_queue_resize_tags(struct request_queue *, int);
  897. extern void blk_queue_invalidate_tags(struct request_queue *);
  898. extern struct blk_queue_tag *blk_init_tags(int);
  899. extern void blk_free_tags(struct blk_queue_tag *);
  900. static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt,
  901. int tag)
  902. {
  903. if (unlikely(bqt == NULL || tag >= bqt->real_max_depth))
  904. return NULL;
  905. return bqt->tag_index[tag];
  906. }
  907. extern int blkdev_issue_flush(struct block_device *, sector_t *);
  908. extern int blkdev_issue_discard(struct block_device *,
  909. sector_t sector, sector_t nr_sects, gfp_t);
  910. static inline int sb_issue_discard(struct super_block *sb,
  911. sector_t block, sector_t nr_blocks)
  912. {
  913. block <<= (sb->s_blocksize_bits - 9);
  914. nr_blocks <<= (sb->s_blocksize_bits - 9);
  915. return blkdev_issue_discard(sb->s_bdev, block, nr_blocks, GFP_KERNEL);
  916. }
  917. /*
  918. * command filter functions
  919. */
  920. extern int blk_verify_command(struct blk_cmd_filter *filter,
  921. unsigned char *cmd, fmode_t has_write_perm);
  922. extern void blk_unregister_filter(struct gendisk *disk);
  923. extern void blk_set_cmd_filter_defaults(struct blk_cmd_filter *filter);
  924. #define MAX_PHYS_SEGMENTS 128
  925. #define MAX_HW_SEGMENTS 128
  926. #define SAFE_MAX_SECTORS 255
  927. #define BLK_DEF_MAX_SECTORS 1024
  928. #define MAX_SEGMENT_SIZE 65536
  929. #define BLK_SEG_BOUNDARY_MASK 0xFFFFFFFFUL
  930. #define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist)
  931. static inline int queue_hardsect_size(struct request_queue *q)
  932. {
  933. int retval = 512;
  934. if (q && q->hardsect_size)
  935. retval = q->hardsect_size;
  936. return retval;
  937. }
  938. static inline int bdev_hardsect_size(struct block_device *bdev)
  939. {
  940. return queue_hardsect_size(bdev_get_queue(bdev));
  941. }
  942. static inline int queue_dma_alignment(struct request_queue *q)
  943. {
  944. return q ? q->dma_alignment : 511;
  945. }
  946. static inline int blk_rq_aligned(struct request_queue *q, void *addr,
  947. unsigned int len)
  948. {
  949. unsigned int alignment = queue_dma_alignment(q) | q->dma_pad_mask;
  950. return !((unsigned long)addr & alignment) && !(len & alignment);
  951. }
  952. /* assumes size > 256 */
  953. static inline unsigned int blksize_bits(unsigned int size)
  954. {
  955. unsigned int bits = 8;
  956. do {
  957. bits++;
  958. size >>= 1;
  959. } while (size > 256);
  960. return bits;
  961. }
  962. static inline unsigned int block_size(struct block_device *bdev)
  963. {
  964. return bdev->bd_block_size;
  965. }
  966. typedef struct {struct page *v;} Sector;
  967. unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *);
  968. static inline void put_dev_sector(Sector p)
  969. {
  970. page_cache_release(p.v);
  971. }
  972. struct work_struct;
  973. int kblockd_schedule_work(struct request_queue *q, struct work_struct *work);
  974. #define MODULE_ALIAS_BLOCKDEV(major,minor) \
  975. MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor))
  976. #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \
  977. MODULE_ALIAS("block-major-" __stringify(major) "-*")
  978. #if defined(CONFIG_BLK_DEV_INTEGRITY)
  979. #define INTEGRITY_FLAG_READ 2 /* verify data integrity on read */
  980. #define INTEGRITY_FLAG_WRITE 4 /* generate data integrity on write */
  981. struct blk_integrity_exchg {
  982. void *prot_buf;
  983. void *data_buf;
  984. sector_t sector;
  985. unsigned int data_size;
  986. unsigned short sector_size;
  987. const char *disk_name;
  988. };
  989. typedef void (integrity_gen_fn) (struct blk_integrity_exchg *);
  990. typedef int (integrity_vrfy_fn) (struct blk_integrity_exchg *);
  991. typedef void (integrity_set_tag_fn) (void *, void *, unsigned int);
  992. typedef void (integrity_get_tag_fn) (void *, void *, unsigned int);
  993. struct blk_integrity {
  994. integrity_gen_fn *generate_fn;
  995. integrity_vrfy_fn *verify_fn;
  996. integrity_set_tag_fn *set_tag_fn;
  997. integrity_get_tag_fn *get_tag_fn;
  998. unsigned short flags;
  999. unsigned short tuple_size;
  1000. unsigned short sector_size;
  1001. unsigned short tag_size;
  1002. const char *name;
  1003. struct kobject kobj;
  1004. };
  1005. extern int blk_integrity_register(struct gendisk *, struct blk_integrity *);
  1006. extern void blk_integrity_unregister(struct gendisk *);
  1007. extern int blk_integrity_compare(struct gendisk *, struct gendisk *);
  1008. extern int blk_rq_map_integrity_sg(struct request *, struct scatterlist *);
  1009. extern int blk_rq_count_integrity_sg(struct request *);
  1010. static inline
  1011. struct blk_integrity *bdev_get_integrity(struct block_device *bdev)
  1012. {
  1013. return bdev->bd_disk->integrity;
  1014. }
  1015. static inline struct blk_integrity *blk_get_integrity(struct gendisk *disk)
  1016. {
  1017. return disk->integrity;
  1018. }
  1019. static inline int blk_integrity_rq(struct request *rq)
  1020. {
  1021. if (rq->bio == NULL)
  1022. return 0;
  1023. return bio_integrity(rq->bio);
  1024. }
  1025. #else /* CONFIG_BLK_DEV_INTEGRITY */
  1026. #define blk_integrity_rq(rq) (0)
  1027. #define blk_rq_count_integrity_sg(a) (0)
  1028. #define blk_rq_map_integrity_sg(a, b) (0)
  1029. #define bdev_get_integrity(a) (0)
  1030. #define blk_get_integrity(a) (0)
  1031. #define blk_integrity_compare(a, b) (0)
  1032. #define blk_integrity_register(a, b) (0)
  1033. #define blk_integrity_unregister(a) do { } while (0);
  1034. #endif /* CONFIG_BLK_DEV_INTEGRITY */
  1035. struct block_device_operations {
  1036. int (*open) (struct block_device *, fmode_t);
  1037. int (*release) (struct gendisk *, fmode_t);
  1038. int (*locked_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
  1039. int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
  1040. int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
  1041. int (*direct_access) (struct block_device *, sector_t,
  1042. void **, unsigned long *);
  1043. int (*media_changed) (struct gendisk *);
  1044. int (*revalidate_disk) (struct gendisk *);
  1045. int (*getgeo)(struct block_device *, struct hd_geometry *);
  1046. struct module *owner;
  1047. };
  1048. extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int,
  1049. unsigned long);
  1050. #else /* CONFIG_BLOCK */
  1051. /*
  1052. * stubs for when the block layer is configured out
  1053. */
  1054. #define buffer_heads_over_limit 0
  1055. static inline long nr_blockdev_pages(void)
  1056. {
  1057. return 0;
  1058. }
  1059. #endif /* CONFIG_BLOCK */
  1060. #endif