| #ifndef _LINUX_BLKDEV_H |
| #define _LINUX_BLKDEV_H |
| |
| #include <linux/config.h> |
| #include <linux/major.h> |
| #include <linux/genhd.h> |
| #include <linux/list.h> |
| #include <linux/timer.h> |
| #include <linux/workqueue.h> |
| #include <linux/pagemap.h> |
| #include <linux/backing-dev.h> |
| #include <linux/wait.h> |
| #include <linux/mempool.h> |
| #include <linux/bio.h> |
| #include <linux/module.h> |
| #include <linux/stringify.h> |
| |
| #include <asm/scatterlist.h> |
| |
| struct request_queue; |
| typedef struct request_queue request_queue_t; |
| struct elevator_queue; |
| typedef struct elevator_queue elevator_t; |
| struct request_pm_state; |
| |
| #define BLKDEV_MIN_RQ 4 |
| #define BLKDEV_MAX_RQ 128 /* Default maximum */ |
| |
| /* |
| * This is the per-process anticipatory I/O scheduler state. |
| */ |
| struct as_io_context { |
| spinlock_t lock; |
| |
| void (*dtor)(struct as_io_context *aic); /* destructor */ |
| void (*exit)(struct as_io_context *aic); /* called on task exit */ |
| |
| unsigned long state; |
| atomic_t nr_queued; /* queued reads & sync writes */ |
| atomic_t nr_dispatched; /* number of requests gone to the drivers */ |
| |
| /* IO History tracking */ |
| /* Thinktime */ |
| unsigned long last_end_request; |
| unsigned long ttime_total; |
| unsigned long ttime_samples; |
| unsigned long ttime_mean; |
| /* Layout pattern */ |
| unsigned int seek_samples; |
| sector_t last_request_pos; |
| u64 seek_total; |
| sector_t seek_mean; |
| }; |
| |
| struct cfq_queue; |
| struct cfq_io_context { |
| /* |
| * circular list of cfq_io_contexts belonging to a process io context |
| */ |
| struct list_head list; |
| struct cfq_queue *cfqq; |
| void *key; |
| |
| struct io_context *ioc; |
| |
| unsigned long last_end_request; |
| unsigned long last_queue; |
| unsigned long ttime_total; |
| unsigned long ttime_samples; |
| unsigned long ttime_mean; |
| |
| void (*dtor)(struct cfq_io_context *); |
| void (*exit)(struct cfq_io_context *); |
| }; |
| |
| /* |
| * This is the per-process I/O subsystem state. It is refcounted and |
| * kmalloc'ed. Currently all fields are modified in process io context |
| * (apart from the atomic refcount), so require no locking. |
| */ |
| struct io_context { |
| atomic_t refcount; |
| struct task_struct *task; |
| |
| int (*set_ioprio)(struct io_context *, unsigned int); |
| |
| /* |
| * For request batching |
| */ |
| unsigned long last_waited; /* Time last woken after wait for request */ |
| int nr_batch_requests; /* Number of requests left in the batch */ |
| |
| struct as_io_context *aic; |
| struct cfq_io_context *cic; |
| }; |
| |
| void put_io_context(struct io_context *ioc); |
| void exit_io_context(void); |
| struct io_context *current_io_context(int gfp_flags); |
| struct io_context *get_io_context(int gfp_flags); |
| void copy_io_context(struct io_context **pdst, struct io_context **psrc); |
| void swap_io_context(struct io_context **ioc1, struct io_context **ioc2); |
| |
| struct request; |
| typedef void (rq_end_io_fn)(struct request *); |
| |
| struct request_list { |
| int count[2]; |
| int starved[2]; |
| mempool_t *rq_pool; |
| wait_queue_head_t wait[2]; |
| wait_queue_head_t drain; |
| }; |
| |
| #define BLK_MAX_CDB 16 |
| |
| /* |
| * try to put the fields that are referenced together in the same cacheline |
| */ |
| struct request { |
| struct list_head queuelist; /* looking for ->queue? you must _not_ |
| * access it directly, use |
| * blkdev_dequeue_request! */ |
| unsigned long flags; /* see REQ_ bits below */ |
| |
| /* Maintain bio traversal state for part by part I/O submission. |
| * hard_* are block layer internals, no driver should touch them! |
| */ |
| |
| sector_t sector; /* next sector to submit */ |
| unsigned long nr_sectors; /* no. of sectors left to submit */ |
| /* no. of sectors left to submit in the current segment */ |
| unsigned int current_nr_sectors; |
| |
| sector_t hard_sector; /* next sector to complete */ |
| unsigned long hard_nr_sectors; /* no. of sectors left to complete */ |
| /* no. of sectors left to complete in the current segment */ |
| unsigned int hard_cur_sectors; |
| |
| struct bio *bio; |
| struct bio *biotail; |
| |
| void *elevator_private; |
| |
| unsigned short ioprio; |
| |
| int rq_status; /* should split this into a few status bits */ |
| struct gendisk *rq_disk; |
| int errors; |
| unsigned long start_time; |
| |
| /* Number of scatter-gather DMA addr+len pairs after |
| * physical address coalescing is performed. |
| */ |
| unsigned short nr_phys_segments; |
| |
| /* Number of scatter-gather addr+len pairs after |
| * physical and DMA remapping hardware coalescing is performed. |
| * This is the number of scatter-gather entries the driver |
| * will actually have to deal with after DMA mapping is done. |
| */ |
| unsigned short nr_hw_segments; |
| |
| int tag; |
| char *buffer; |
| |
| int ref_count; |
| request_queue_t *q; |
| struct request_list *rl; |
| |
| struct completion *waiting; |
| void *special; |
| |
| /* |
| * when request is used as a packet command carrier |
| */ |
| unsigned int cmd_len; |
| unsigned char cmd[BLK_MAX_CDB]; |
| |
| unsigned int data_len; |
| void *data; |
| |
| unsigned int sense_len; |
| void *sense; |
| |
| unsigned int timeout; |
| |
| /* |
| * For Power Management requests |
| */ |
| struct request_pm_state *pm; |
| |
| /* |
| * completion callback. end_io_data should be folded in with waiting |
| */ |
| rq_end_io_fn *end_io; |
| void *end_io_data; |
| }; |
| |
| /* |
| * first three bits match BIO_RW* bits, important |
| */ |
| enum rq_flag_bits { |
| __REQ_RW, /* not set, read. set, write */ |
| __REQ_FAILFAST, /* no low level driver retries */ |
| __REQ_SORTED, /* elevator knows about this request */ |
| __REQ_SOFTBARRIER, /* may not be passed by ioscheduler */ |
| __REQ_HARDBARRIER, /* may not be passed by drive either */ |
| __REQ_CMD, /* is a regular fs rw request */ |
| __REQ_NOMERGE, /* don't touch this for merging */ |
| __REQ_STARTED, /* drive already may have started this one */ |
| __REQ_DONTPREP, /* don't call prep for this one */ |
| __REQ_QUEUED, /* uses queueing */ |
| /* |
| * for ATA/ATAPI devices |
| */ |
| __REQ_PC, /* packet command (special) */ |
| __REQ_BLOCK_PC, /* queued down pc from block layer */ |
| __REQ_SENSE, /* sense retrival */ |
| |
| __REQ_FAILED, /* set if the request failed */ |
| __REQ_QUIET, /* don't worry about errors */ |
| __REQ_SPECIAL, /* driver suplied command */ |
| __REQ_DRIVE_CMD, |
| __REQ_DRIVE_TASK, |
| __REQ_DRIVE_TASKFILE, |
| __REQ_PREEMPT, /* set for "ide_preempt" requests */ |
| __REQ_PM_SUSPEND, /* suspend request */ |
| __REQ_PM_RESUME, /* resume request */ |
| __REQ_PM_SHUTDOWN, /* shutdown request */ |
| __REQ_BAR_PREFLUSH, /* barrier pre-flush done */ |
| __REQ_BAR_POSTFLUSH, /* barrier post-flush */ |
| __REQ_BAR_FLUSH, /* rq is the flush request */ |
| __REQ_NR_BITS, /* stops here */ |
| }; |
| |
| #define REQ_RW (1 << __REQ_RW) |
| #define REQ_FAILFAST (1 << __REQ_FAILFAST) |
| #define REQ_SORTED (1 << __REQ_SORTED) |
| #define REQ_SOFTBARRIER (1 << __REQ_SOFTBARRIER) |
| #define REQ_HARDBARRIER (1 << __REQ_HARDBARRIER) |
| #define REQ_CMD (1 << __REQ_CMD) |
| #define REQ_NOMERGE (1 << __REQ_NOMERGE) |
| #define REQ_STARTED (1 << __REQ_STARTED) |
| #define REQ_DONTPREP (1 << __REQ_DONTPREP) |
| #define REQ_QUEUED (1 << __REQ_QUEUED) |
| #define REQ_PC (1 << __REQ_PC) |
| #define REQ_BLOCK_PC (1 << __REQ_BLOCK_PC) |
| #define REQ_SENSE (1 << __REQ_SENSE) |
| #define REQ_FAILED (1 << __REQ_FAILED) |
| #define REQ_QUIET (1 << __REQ_QUIET) |
| #define REQ_SPECIAL (1 << __REQ_SPECIAL) |
| #define REQ_DRIVE_CMD (1 << __REQ_DRIVE_CMD) |
| #define REQ_DRIVE_TASK (1 << __REQ_DRIVE_TASK) |
| #define REQ_DRIVE_TASKFILE (1 << __REQ_DRIVE_TASKFILE) |
| #define REQ_PREEMPT (1 << __REQ_PREEMPT) |
| #define REQ_PM_SUSPEND (1 << __REQ_PM_SUSPEND) |
| #define REQ_PM_RESUME (1 << __REQ_PM_RESUME) |
| #define REQ_PM_SHUTDOWN (1 << __REQ_PM_SHUTDOWN) |
| #define REQ_BAR_PREFLUSH (1 << __REQ_BAR_PREFLUSH) |
| #define REQ_BAR_POSTFLUSH (1 << __REQ_BAR_POSTFLUSH) |
| #define REQ_BAR_FLUSH (1 << __REQ_BAR_FLUSH) |
| |
| /* |
| * State information carried for REQ_PM_SUSPEND and REQ_PM_RESUME |
| * requests. Some step values could eventually be made generic. |
| */ |
| struct request_pm_state |
| { |
| /* PM state machine step value, currently driver specific */ |
| int pm_step; |
| /* requested PM state value (S1, S2, S3, S4, ...) */ |
| u32 pm_state; |
| void* data; /* for driver use */ |
| }; |
| |
| #include <linux/elevator.h> |
| |
| typedef int (merge_request_fn) (request_queue_t *, struct request *, |
| struct bio *); |
| typedef int (merge_requests_fn) (request_queue_t *, struct request *, |
| struct request *); |
| typedef void (request_fn_proc) (request_queue_t *q); |
| typedef int (make_request_fn) (request_queue_t *q, struct bio *bio); |
| typedef int (prep_rq_fn) (request_queue_t *, struct request *); |
| typedef void (unplug_fn) (request_queue_t *); |
| |
| struct bio_vec; |
| typedef int (merge_bvec_fn) (request_queue_t *, struct bio *, struct bio_vec *); |
| typedef void (activity_fn) (void *data, int rw); |
| typedef int (issue_flush_fn) (request_queue_t *, struct gendisk *, sector_t *); |
| typedef int (prepare_flush_fn) (request_queue_t *, struct request *); |
| typedef void (end_flush_fn) (request_queue_t *, struct request *); |
| |
| enum blk_queue_state { |
| Queue_down, |
| Queue_up, |
| }; |
| |
| struct blk_queue_tag { |
| struct request **tag_index; /* map of busy tags */ |
| unsigned long *tag_map; /* bit map of free/busy tags */ |
| struct list_head busy_list; /* fifo list of busy tags */ |
| int busy; /* current depth */ |
| int max_depth; /* what we will send to device */ |
| int real_max_depth; /* what the array can hold */ |
| atomic_t refcnt; /* map can be shared */ |
| }; |
| |
| struct request_queue |
| { |
| /* |
| * Together with queue_head for cacheline sharing |
| */ |
| struct list_head queue_head; |
| struct request *last_merge; |
| elevator_t *elevator; |
| |
| /* |
| * the queue request freelist, one for reads and one for writes |
| */ |
| struct request_list rq; |
| |
| request_fn_proc *request_fn; |
| merge_request_fn *back_merge_fn; |
| merge_request_fn *front_merge_fn; |
| merge_requests_fn *merge_requests_fn; |
| make_request_fn *make_request_fn; |
| prep_rq_fn *prep_rq_fn; |
| unplug_fn *unplug_fn; |
| merge_bvec_fn *merge_bvec_fn; |
| activity_fn *activity_fn; |
| issue_flush_fn *issue_flush_fn; |
| prepare_flush_fn *prepare_flush_fn; |
| end_flush_fn *end_flush_fn; |
| |
| /* |
| * Dispatch queue sorting |
| */ |
| sector_t end_sector; |
| struct request *boundary_rq; |
| |
| /* |
| * Auto-unplugging state |
| */ |
| struct timer_list unplug_timer; |
| int unplug_thresh; /* After this many requests */ |
| unsigned long unplug_delay; /* After this many jiffies */ |
| struct work_struct unplug_work; |
| |
| struct backing_dev_info backing_dev_info; |
| |
| /* |
| * The queue owner gets to use this for whatever they like. |
| * ll_rw_blk doesn't touch it. |
| */ |
| void *queuedata; |
| |
| void *activity_data; |
| |
| /* |
| * queue needs bounce pages for pages above this limit |
| */ |
| unsigned long bounce_pfn; |
| unsigned int bounce_gfp; |
| |
| /* |
| * various queue flags, see QUEUE_* below |
| */ |
| unsigned long queue_flags; |
| |
| /* |
| * protects queue structures from reentrancy. ->__queue_lock should |
| * _never_ be used directly, it is queue private. always use |
| * ->queue_lock. |
| */ |
| spinlock_t __queue_lock; |
| spinlock_t *queue_lock; |
| |
| /* |
| * queue kobject |
| */ |
| struct kobject kobj; |
| |
| /* |
| * queue settings |
| */ |
| unsigned long nr_requests; /* Max # of requests */ |
| unsigned int nr_congestion_on; |
| unsigned int nr_congestion_off; |
| unsigned int nr_batching; |
| |
| unsigned short max_sectors; |
| unsigned short max_hw_sectors; |
| unsigned short max_phys_segments; |
| unsigned short max_hw_segments; |
| unsigned short hardsect_size; |
| unsigned int max_segment_size; |
| |
| unsigned long seg_boundary_mask; |
| unsigned int dma_alignment; |
| |
| struct blk_queue_tag *queue_tags; |
| |
| atomic_t refcnt; |
| |
| unsigned int in_flight; |
| |
| /* |
| * sg stuff |
| */ |
| unsigned int sg_timeout; |
| unsigned int sg_reserved_size; |
| int node; |
| |
| struct list_head drain_list; |
| |
| /* |
| * reserved for flush operations |
| */ |
| struct request *flush_rq; |
| unsigned char ordered; |
| }; |
| |
| enum { |
| QUEUE_ORDERED_NONE, |
| QUEUE_ORDERED_TAG, |
| QUEUE_ORDERED_FLUSH, |
| }; |
| |
| #define RQ_INACTIVE (-1) |
| #define RQ_ACTIVE 1 |
| #define RQ_SCSI_BUSY 0xffff |
| #define RQ_SCSI_DONE 0xfffe |
| #define RQ_SCSI_DISCONNECTING 0xffe0 |
| |
| #define QUEUE_FLAG_CLUSTER 0 /* cluster several segments into 1 */ |
| #define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */ |
| #define QUEUE_FLAG_STOPPED 2 /* queue is stopped */ |
| #define QUEUE_FLAG_READFULL 3 /* write queue has been filled */ |
| #define QUEUE_FLAG_WRITEFULL 4 /* read queue has been filled */ |
| #define QUEUE_FLAG_DEAD 5 /* queue being torn down */ |
| #define QUEUE_FLAG_REENTER 6 /* Re-entrancy avoidance */ |
| #define QUEUE_FLAG_PLUGGED 7 /* queue is plugged */ |
| #define QUEUE_FLAG_DRAIN 8 /* draining queue for sched switch */ |
| #define QUEUE_FLAG_FLUSH 9 /* doing barrier flush sequence */ |
| |
| #define blk_queue_plugged(q) test_bit(QUEUE_FLAG_PLUGGED, &(q)->queue_flags) |
| #define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags) |
| #define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags) |
| #define blk_queue_flushing(q) test_bit(QUEUE_FLAG_FLUSH, &(q)->queue_flags) |
| |
| #define blk_fs_request(rq) ((rq)->flags & REQ_CMD) |
| #define blk_pc_request(rq) ((rq)->flags & REQ_BLOCK_PC) |
| #define blk_noretry_request(rq) ((rq)->flags & REQ_FAILFAST) |
| #define blk_rq_started(rq) ((rq)->flags & REQ_STARTED) |
| |
| #define blk_account_rq(rq) (blk_rq_started(rq) && blk_fs_request(rq)) |
| |
| #define blk_pm_suspend_request(rq) ((rq)->flags & REQ_PM_SUSPEND) |
| #define blk_pm_resume_request(rq) ((rq)->flags & REQ_PM_RESUME) |
| #define blk_pm_request(rq) \ |
| ((rq)->flags & (REQ_PM_SUSPEND | REQ_PM_RESUME)) |
| |
| #define blk_sorted_rq(rq) ((rq)->flags & REQ_SORTED) |
| #define blk_barrier_rq(rq) ((rq)->flags & REQ_HARDBARRIER) |
| #define blk_barrier_preflush(rq) ((rq)->flags & REQ_BAR_PREFLUSH) |
| #define blk_barrier_postflush(rq) ((rq)->flags & REQ_BAR_POSTFLUSH) |
| |
| #define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist) |
| |
| #define rq_data_dir(rq) ((rq)->flags & 1) |
| |
| static inline int blk_queue_full(struct request_queue *q, int rw) |
| { |
| if (rw == READ) |
| return test_bit(QUEUE_FLAG_READFULL, &q->queue_flags); |
| return test_bit(QUEUE_FLAG_WRITEFULL, &q->queue_flags); |
| } |
| |
| static inline void blk_set_queue_full(struct request_queue *q, int rw) |
| { |
| if (rw == READ) |
| set_bit(QUEUE_FLAG_READFULL, &q->queue_flags); |
| else |
| set_bit(QUEUE_FLAG_WRITEFULL, &q->queue_flags); |
| } |
| |
| static inline void blk_clear_queue_full(struct request_queue *q, int rw) |
| { |
| if (rw == READ) |
| clear_bit(QUEUE_FLAG_READFULL, &q->queue_flags); |
| else |
| clear_bit(QUEUE_FLAG_WRITEFULL, &q->queue_flags); |
| } |
| |
| |
| /* |
| * mergeable request must not have _NOMERGE or _BARRIER bit set, nor may |
| * it already be started by driver. |
| */ |
| #define RQ_NOMERGE_FLAGS \ |
| (REQ_NOMERGE | REQ_STARTED | REQ_HARDBARRIER | REQ_SOFTBARRIER) |
| #define rq_mergeable(rq) \ |
| (!((rq)->flags & RQ_NOMERGE_FLAGS) && blk_fs_request((rq))) |
| |
| /* |
| * noop, requests are automagically marked as active/inactive by I/O |
| * scheduler -- see elv_next_request |
| */ |
| #define blk_queue_headactive(q, head_active) |
| |
| /* |
| * q->prep_rq_fn return values |
| */ |
| #define BLKPREP_OK 0 /* serve it */ |
| #define BLKPREP_KILL 1 /* fatal error, kill */ |
| #define BLKPREP_DEFER 2 /* leave on queue */ |
| |
| extern unsigned long blk_max_low_pfn, blk_max_pfn; |
| |
| /* |
| * standard bounce addresses: |
| * |
| * BLK_BOUNCE_HIGH : bounce all highmem pages |
| * BLK_BOUNCE_ANY : don't bounce anything |
| * BLK_BOUNCE_ISA : bounce pages above ISA DMA boundary |
| */ |
| #define BLK_BOUNCE_HIGH ((u64)blk_max_low_pfn << PAGE_SHIFT) |
| #define BLK_BOUNCE_ANY ((u64)blk_max_pfn << PAGE_SHIFT) |
| #define BLK_BOUNCE_ISA (ISA_DMA_THRESHOLD) |
| |
| #ifdef CONFIG_MMU |
| extern int init_emergency_isa_pool(void); |
| extern void blk_queue_bounce(request_queue_t *q, struct bio **bio); |
| #else |
| static inline int init_emergency_isa_pool(void) |
| { |
| return 0; |
| } |
| static inline void blk_queue_bounce(request_queue_t *q, struct bio **bio) |
| { |
| } |
| #endif /* CONFIG_MMU */ |
| |
| #define rq_for_each_bio(_bio, rq) \ |
| if ((rq->bio)) \ |
| for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next) |
| |
| struct sec_size { |
| unsigned block_size; |
| unsigned block_size_bits; |
| }; |
| |
| extern int blk_register_queue(struct gendisk *disk); |
| extern void blk_unregister_queue(struct gendisk *disk); |
| extern void register_disk(struct gendisk *dev); |
| extern void generic_make_request(struct bio *bio); |
| extern void blk_put_request(struct request *); |
| extern void blk_end_sync_rq(struct request *rq); |
| extern void blk_attempt_remerge(request_queue_t *, struct request *); |
| extern struct request *blk_get_request(request_queue_t *, int, int); |
| extern void blk_insert_request(request_queue_t *, struct request *, int, void *); |
| extern void blk_requeue_request(request_queue_t *, struct request *); |
| extern void blk_plug_device(request_queue_t *); |
| extern int blk_remove_plug(request_queue_t *); |
| extern void blk_recount_segments(request_queue_t *, struct bio *); |
| extern int scsi_cmd_ioctl(struct file *, struct gendisk *, unsigned int, void __user *); |
| extern void blk_start_queue(request_queue_t *q); |
| extern void blk_stop_queue(request_queue_t *q); |
| extern void blk_sync_queue(struct request_queue *q); |
| extern void __blk_stop_queue(request_queue_t *q); |
| extern void blk_run_queue(request_queue_t *); |
| extern void blk_queue_activity_fn(request_queue_t *, activity_fn *, void *); |
| extern int blk_rq_map_user(request_queue_t *, struct request *, void __user *, unsigned int); |
| extern int blk_rq_unmap_user(struct bio *, unsigned int); |
| extern int blk_rq_map_kern(request_queue_t *, struct request *, void *, unsigned int, unsigned int); |
| extern int blk_rq_map_user_iov(request_queue_t *, struct request *, struct sg_iovec *, int); |
| extern int blk_execute_rq(request_queue_t *, struct gendisk *, |
| struct request *, int); |
| static inline request_queue_t *bdev_get_queue(struct block_device *bdev) |
| { |
| return bdev->bd_disk->queue; |
| } |
| |
| static inline void blk_run_backing_dev(struct backing_dev_info *bdi, |
| struct page *page) |
| { |
| if (bdi && bdi->unplug_io_fn) |
| bdi->unplug_io_fn(bdi, page); |
| } |
| |
| static inline void blk_run_address_space(struct address_space *mapping) |
| { |
| if (mapping) |
| blk_run_backing_dev(mapping->backing_dev_info, NULL); |
| } |
| |
| /* |
| * end_request() and friends. Must be called with the request queue spinlock |
| * acquired. All functions called within end_request() _must_be_ atomic. |
| * |
| * Several drivers define their own end_request and call |
| * end_that_request_first() and end_that_request_last() |
| * for parts of the original function. This prevents |
| * code duplication in drivers. |
| */ |
| extern int end_that_request_first(struct request *, int, int); |
| extern int end_that_request_chunk(struct request *, int, int); |
| extern void end_that_request_last(struct request *); |
| extern void end_request(struct request *req, int uptodate); |
| |
| /* |
| * end_that_request_first/chunk() takes an uptodate argument. we account |
| * any value <= as an io error. 0 means -EIO for compatability reasons, |
| * any other < 0 value is the direct error type. An uptodate value of |
| * 1 indicates successful io completion |
| */ |
| #define end_io_error(uptodate) (unlikely((uptodate) <= 0)) |
| |
| static inline void blkdev_dequeue_request(struct request *req) |
| { |
| elv_dequeue_request(req->q, req); |
| } |
| |
| /* |
| * This should be in elevator.h, but that requires pulling in rq and q |
| */ |
| static inline void elv_dispatch_add_tail(struct request_queue *q, |
| struct request *rq) |
| { |
| if (q->last_merge == rq) |
| q->last_merge = NULL; |
| |
| q->end_sector = rq_end_sector(rq); |
| q->boundary_rq = rq; |
| list_add_tail(&rq->queuelist, &q->queue_head); |
| } |
| |
| /* |
| * Access functions for manipulating queue properties |
| */ |
| extern request_queue_t *blk_init_queue_node(request_fn_proc *rfn, |
| spinlock_t *lock, int node_id); |
| extern request_queue_t *blk_init_queue(request_fn_proc *, spinlock_t *); |
| extern void blk_cleanup_queue(request_queue_t *); |
| extern void blk_queue_make_request(request_queue_t *, make_request_fn *); |
| extern void blk_queue_bounce_limit(request_queue_t *, u64); |
| extern void blk_queue_max_sectors(request_queue_t *, unsigned short); |
| extern void blk_queue_max_phys_segments(request_queue_t *, unsigned short); |
| extern void blk_queue_max_hw_segments(request_queue_t *, unsigned short); |
| extern void blk_queue_max_segment_size(request_queue_t *, unsigned int); |
| extern void blk_queue_hardsect_size(request_queue_t *, unsigned short); |
| extern void blk_queue_stack_limits(request_queue_t *t, request_queue_t *b); |
| extern void blk_queue_segment_boundary(request_queue_t *, unsigned long); |
| extern void blk_queue_prep_rq(request_queue_t *, prep_rq_fn *pfn); |
| extern void blk_queue_merge_bvec(request_queue_t *, merge_bvec_fn *); |
| extern void blk_queue_dma_alignment(request_queue_t *, int); |
| extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev); |
| extern void blk_queue_ordered(request_queue_t *, int); |
| extern void blk_queue_issue_flush_fn(request_queue_t *, issue_flush_fn *); |
| extern struct request *blk_start_pre_flush(request_queue_t *,struct request *); |
| extern int blk_complete_barrier_rq(request_queue_t *, struct request *, int); |
| extern int blk_complete_barrier_rq_locked(request_queue_t *, struct request *, int); |
| |
| extern int blk_rq_map_sg(request_queue_t *, struct request *, struct scatterlist *); |
| extern void blk_dump_rq_flags(struct request *, char *); |
| extern void generic_unplug_device(request_queue_t *); |
| extern void __generic_unplug_device(request_queue_t *); |
| extern long nr_blockdev_pages(void); |
| extern void blk_wait_queue_drained(request_queue_t *, int); |
| extern void blk_finish_queue_drain(request_queue_t *); |
| |
| int blk_get_queue(request_queue_t *); |
| request_queue_t *blk_alloc_queue(int gfp_mask); |
| request_queue_t *blk_alloc_queue_node(int,int); |
| #define blk_put_queue(q) blk_cleanup_queue((q)) |
| |
| /* |
| * tag stuff |
| */ |
| #define blk_queue_tag_depth(q) ((q)->queue_tags->busy) |
| #define blk_queue_tag_queue(q) ((q)->queue_tags->busy < (q)->queue_tags->max_depth) |
| #define blk_rq_tagged(rq) ((rq)->flags & REQ_QUEUED) |
| extern int blk_queue_start_tag(request_queue_t *, struct request *); |
| extern struct request *blk_queue_find_tag(request_queue_t *, int); |
| extern void blk_queue_end_tag(request_queue_t *, struct request *); |
| extern int blk_queue_init_tags(request_queue_t *, int, struct blk_queue_tag *); |
| extern void blk_queue_free_tags(request_queue_t *); |
| extern int blk_queue_resize_tags(request_queue_t *, int); |
| extern void blk_queue_invalidate_tags(request_queue_t *); |
| extern long blk_congestion_wait(int rw, long timeout); |
| |
| extern void blk_rq_bio_prep(request_queue_t *, struct request *, struct bio *); |
| extern int blkdev_issue_flush(struct block_device *, sector_t *); |
| |
| #define MAX_PHYS_SEGMENTS 128 |
| #define MAX_HW_SEGMENTS 128 |
| #define MAX_SECTORS 255 |
| |
| #define MAX_SEGMENT_SIZE 65536 |
| |
| #define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist) |
| |
| static inline int queue_hardsect_size(request_queue_t *q) |
| { |
| int retval = 512; |
| |
| if (q && q->hardsect_size) |
| retval = q->hardsect_size; |
| |
| return retval; |
| } |
| |
| static inline int bdev_hardsect_size(struct block_device *bdev) |
| { |
| return queue_hardsect_size(bdev_get_queue(bdev)); |
| } |
| |
| static inline int queue_dma_alignment(request_queue_t *q) |
| { |
| int retval = 511; |
| |
| if (q && q->dma_alignment) |
| retval = q->dma_alignment; |
| |
| return retval; |
| } |
| |
| static inline int bdev_dma_aligment(struct block_device *bdev) |
| { |
| return queue_dma_alignment(bdev_get_queue(bdev)); |
| } |
| |
| #define blk_finished_io(nsects) do { } while (0) |
| #define blk_started_io(nsects) do { } while (0) |
| |
| /* assumes size > 256 */ |
| static inline unsigned int blksize_bits(unsigned int size) |
| { |
| unsigned int bits = 8; |
| do { |
| bits++; |
| size >>= 1; |
| } while (size > 256); |
| return bits; |
| } |
| |
| static inline unsigned int block_size(struct block_device *bdev) |
| { |
| return bdev->bd_block_size; |
| } |
| |
| typedef struct {struct page *v;} Sector; |
| |
| unsigned char *read_dev_sector(struct block_device *, sector_t, Sector *); |
| |
| static inline void put_dev_sector(Sector p) |
| { |
| page_cache_release(p.v); |
| } |
| |
| struct work_struct; |
| int kblockd_schedule_work(struct work_struct *work); |
| void kblockd_flush(void); |
| |
| #ifdef CONFIG_LBD |
| # include <asm/div64.h> |
| # define sector_div(a, b) do_div(a, b) |
| #else |
| # define sector_div(n, b)( \ |
| { \ |
| int _res; \ |
| _res = (n) % (b); \ |
| (n) /= (b); \ |
| _res; \ |
| } \ |
| ) |
| #endif |
| |
| #define MODULE_ALIAS_BLOCKDEV(major,minor) \ |
| MODULE_ALIAS("block-major-" __stringify(major) "-" __stringify(minor)) |
| #define MODULE_ALIAS_BLOCKDEV_MAJOR(major) \ |
| MODULE_ALIAS("block-major-" __stringify(major) "-*") |
| |
| |
| #endif |