#ifndef _LINUX_BLKDEV_H #define _LINUX_BLKDEV_H #ifdef CONFIG_BLOCK #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include struct scsi_ioctl_command; struct request_queue; typedef struct request_queue request_queue_t __deprecated; struct elevator_queue; typedef struct elevator_queue elevator_t; struct request_pm_state; struct blk_trace; struct request; struct sg_io_hdr; #define BLKDEV_MIN_RQ 4 #define BLKDEV_MAX_RQ 128 /* Default maximum */ int put_io_context(struct io_context *ioc); void exit_io_context(void); struct io_context *get_io_context(gfp_t gfp_flags, int node); struct io_context *alloc_io_context(gfp_t gfp_flags, int node); void copy_io_context(struct io_context **pdst, struct io_context **psrc); struct request; typedef void (rq_end_io_fn)(struct request *, int); struct request_list { int count[2]; int starved[2]; int elvpriv; mempool_t *rq_pool; wait_queue_head_t wait[2]; }; /* * request command types */ enum rq_cmd_type_bits { REQ_TYPE_FS = 1, /* fs request */ REQ_TYPE_BLOCK_PC, /* scsi command */ REQ_TYPE_SENSE, /* sense request */ REQ_TYPE_PM_SUSPEND, /* suspend request */ REQ_TYPE_PM_RESUME, /* resume request */ REQ_TYPE_PM_SHUTDOWN, /* shutdown request */ REQ_TYPE_FLUSH, /* flush request */ REQ_TYPE_SPECIAL, /* driver defined type */ REQ_TYPE_LINUX_BLOCK, /* generic block layer message */ /* * for ATA/ATAPI devices. this really doesn't belong here, ide should * use REQ_TYPE_SPECIAL and use rq->cmd[0] with the range of driver * private REQ_LB opcodes to differentiate what type of request this is */ REQ_TYPE_ATA_TASKFILE, REQ_TYPE_ATA_PC, }; /* * For request of type REQ_TYPE_LINUX_BLOCK, rq->cmd[0] is the opcode being * sent down (similar to how REQ_TYPE_BLOCK_PC means that ->cmd[] holds a * SCSI cdb. * * 0x00 -> 0x3f are driver private, to be used for whatever purpose they need, * typically to differentiate REQ_TYPE_SPECIAL requests. * */ enum { /* * just examples for now */ REQ_LB_OP_EJECT = 0x40, /* eject request */ REQ_LB_OP_FLUSH = 0x41, /* flush device */ }; /* * request type modified bits. 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_FUA, /* forced unit access */ __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 */ __REQ_ELVPRIV, /* elevator private data attached */ __REQ_FAILED, /* set if the request failed */ __REQ_QUIET, /* don't worry about errors */ __REQ_PREEMPT, /* set for "ide_preempt" requests */ __REQ_ORDERED_COLOR, /* is before or after barrier */ __REQ_RW_SYNC, /* request is sync (O_DIRECT) */ __REQ_ALLOCED, /* request came from our alloc pool */ __REQ_RW_META, /* metadata io 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_FUA (1 << __REQ_FUA) #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_ELVPRIV (1 << __REQ_ELVPRIV) #define REQ_FAILED (1 << __REQ_FAILED) #define REQ_QUIET (1 << __REQ_QUIET) #define REQ_PREEMPT (1 << __REQ_PREEMPT) #define REQ_ORDERED_COLOR (1 << __REQ_ORDERED_COLOR) #define REQ_RW_SYNC (1 << __REQ_RW_SYNC) #define REQ_ALLOCED (1 << __REQ_ALLOCED) #define REQ_RW_META (1 << __REQ_RW_META) #define BLK_MAX_CDB 16 /* * try to put the fields that are referenced together in the same cacheline. * if you modify this structure, be sure to check block/blk-core.c:rq_init() * as well! */ struct request { struct list_head queuelist; struct list_head donelist; struct request_queue *q; unsigned int cmd_flags; enum rq_cmd_type_bits cmd_type; /* 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 */ sector_t hard_sector; /* next sector to complete */ unsigned long nr_sectors; /* no. of sectors left to submit */ unsigned long hard_nr_sectors; /* no. of sectors left to complete */ /* no. of sectors left to submit in the current segment */ unsigned int current_nr_sectors; /* no. of sectors left to complete in the current segment */ unsigned int hard_cur_sectors; struct bio *bio; struct bio *biotail; struct hlist_node hash; /* merge hash */ /* * The rb_node is only used inside the io scheduler, requests * are pruned when moved to the dispatch queue. So let the * completion_data share space with the rb_node. */ union { struct rb_node rb_node; /* sort/lookup */ void *completion_data; }; /* * two pointers are available for the IO schedulers, if they need * more they have to dynamically allocate it. */ void *elevator_private; void *elevator_private2; struct gendisk *rq_disk; 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; unsigned short ioprio; void *special; char *buffer; int tag; int errors; int ref_count; /* * when request is used as a packet command carrier */ unsigned int cmd_len; unsigned char cmd[BLK_MAX_CDB]; unsigned int data_len; unsigned int extra_len; /* length of alignment and padding */ unsigned int sense_len; void *data; void *sense; unsigned int timeout; int retries; /* * completion callback. */ rq_end_io_fn *end_io; void *end_io_data; /* for bidi */ struct request *next_rq; }; /* * State information carried for REQ_TYPE_PM_SUSPEND and REQ_TYPE_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 typedef void (request_fn_proc) (struct request_queue *q); typedef int (make_request_fn) (struct request_queue *q, struct bio *bio); typedef int (prep_rq_fn) (struct request_queue *, struct request *); typedef void (unplug_fn) (struct request_queue *); struct bio_vec; typedef int (merge_bvec_fn) (struct request_queue *, struct bio *, struct bio_vec *); typedef void (prepare_flush_fn) (struct request_queue *, struct request *); typedef void (softirq_done_fn)(struct request *); typedef int (dma_drain_needed_fn)(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 */ 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; make_request_fn *make_request_fn; prep_rq_fn *prep_rq_fn; unplug_fn *unplug_fn; merge_bvec_fn *merge_bvec_fn; prepare_flush_fn *prepare_flush_fn; softirq_done_fn *softirq_done_fn; dma_drain_needed_fn *dma_drain_needed; /* * 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; /* * queue needs bounce pages for pages above this limit */ unsigned long bounce_pfn; gfp_t 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 int max_sectors; unsigned int 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; void *dma_drain_buffer; unsigned int dma_drain_size; unsigned int dma_alignment; struct blk_queue_tag *queue_tags; struct list_head tag_busy_list; unsigned int nr_sorted; unsigned int in_flight; /* * sg stuff */ unsigned int sg_timeout; unsigned int sg_reserved_size; int node; #ifdef CONFIG_BLK_DEV_IO_TRACE struct blk_trace *blk_trace; #endif /* * reserved for flush operations */ unsigned int ordered, next_ordered, ordseq; int orderr, ordcolor; struct request pre_flush_rq, bar_rq, post_flush_rq; struct request *orig_bar_rq; struct mutex sysfs_lock; #if defined(CONFIG_BLK_DEV_BSG) struct bsg_class_device bsg_dev; #endif }; #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 /* read queue has been filled */ #define QUEUE_FLAG_WRITEFULL 4 /* write 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_ELVSWITCH 8 /* don't use elevator, just do FIFO */ #define QUEUE_FLAG_BIDI 9 /* queue supports bidi requests */ enum { /* * Hardbarrier is supported with one of the following methods. * * NONE : hardbarrier unsupported * DRAIN : ordering by draining is enough * DRAIN_FLUSH : ordering by draining w/ pre and post flushes * DRAIN_FUA : ordering by draining w/ pre flush and FUA write * TAG : ordering by tag is enough * TAG_FLUSH : ordering by tag w/ pre and post flushes * TAG_FUA : ordering by tag w/ pre flush and FUA write */ QUEUE_ORDERED_NONE = 0x00, QUEUE_ORDERED_DRAIN = 0x01, QUEUE_ORDERED_TAG = 0x02, QUEUE_ORDERED_PREFLUSH = 0x10, QUEUE_ORDERED_POSTFLUSH = 0x20, QUEUE_ORDERED_FUA = 0x40, QUEUE_ORDERED_DRAIN_FLUSH = QUEUE_ORDERED_DRAIN | QUEUE_ORDERED_PREFLUSH | QUEUE_ORDERED_POSTFLUSH, QUEUE_ORDERED_DRAIN_FUA = QUEUE_ORDERED_DRAIN | QUEUE_ORDERED_PREFLUSH | QUEUE_ORDERED_FUA, QUEUE_ORDERED_TAG_FLUSH = QUEUE_ORDERED_TAG | QUEUE_ORDERED_PREFLUSH | QUEUE_ORDERED_POSTFLUSH, QUEUE_ORDERED_TAG_FUA = QUEUE_ORDERED_TAG | QUEUE_ORDERED_PREFLUSH | QUEUE_ORDERED_FUA, /* * Ordered operation sequence */ QUEUE_ORDSEQ_STARTED = 0x01, /* flushing in progress */ QUEUE_ORDSEQ_DRAIN = 0x02, /* waiting for the queue to be drained */ QUEUE_ORDSEQ_PREFLUSH = 0x04, /* pre-flushing in progress */ QUEUE_ORDSEQ_BAR = 0x08, /* original barrier req in progress */ QUEUE_ORDSEQ_POSTFLUSH = 0x10, /* post-flushing in progress */ QUEUE_ORDSEQ_DONE = 0x20, }; #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) ((q)->ordseq) #define blk_fs_request(rq) ((rq)->cmd_type == REQ_TYPE_FS) #define blk_pc_request(rq) ((rq)->cmd_type == REQ_TYPE_BLOCK_PC) #define blk_special_request(rq) ((rq)->cmd_type == REQ_TYPE_SPECIAL) #define blk_sense_request(rq) ((rq)->cmd_type == REQ_TYPE_SENSE) #define blk_noretry_request(rq) ((rq)->cmd_flags & REQ_FAILFAST) #define blk_rq_started(rq) ((rq)->cmd_flags & REQ_STARTED) #define blk_account_rq(rq) (blk_rq_started(rq) && blk_fs_request(rq)) #define blk_pm_suspend_request(rq) ((rq)->cmd_type == REQ_TYPE_PM_SUSPEND) #define blk_pm_resume_request(rq) ((rq)->cmd_type == REQ_TYPE_PM_RESUME) #define blk_pm_request(rq) \ (blk_pm_suspend_request(rq) || blk_pm_resume_request(rq)) #define blk_sorted_rq(rq) ((rq)->cmd_flags & REQ_SORTED) #define blk_barrier_rq(rq) ((rq)->cmd_flags & REQ_HARDBARRIER) #define blk_fua_rq(rq) ((rq)->cmd_flags & REQ_FUA) #define blk_bidi_rq(rq) ((rq)->next_rq != NULL) #define blk_empty_barrier(rq) (blk_barrier_rq(rq) && blk_fs_request(rq) && !(rq)->hard_nr_sectors) /* rq->queuelist of dequeued request must be list_empty() */ #define blk_queued_rq(rq) (!list_empty(&(rq)->queuelist)) #define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist) #define rq_data_dir(rq) ((rq)->cmd_flags & 1) /* * We regard a request as sync, if it's a READ or a SYNC write. */ #define rq_is_sync(rq) (rq_data_dir((rq)) == READ || (rq)->cmd_flags & REQ_RW_SYNC) #define rq_is_meta(rq) ((rq)->cmd_flags & REQ_RW_META) 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)->cmd_flags & RQ_NOMERGE_FLAGS) && blk_fs_request((rq))) /* * 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) /* * default timeout for SG_IO if none specified */ #define BLK_DEFAULT_SG_TIMEOUT (60 * HZ) #ifdef CONFIG_BOUNCE extern int init_emergency_isa_pool(void); extern void blk_queue_bounce(struct request_queue *q, struct bio **bio); #else static inline int init_emergency_isa_pool(void) { return 0; } static inline void blk_queue_bounce(struct request_queue *q, struct bio **bio) { } #endif /* CONFIG_MMU */ struct req_iterator { int i; struct bio *bio; }; /* This should not be used directly - use rq_for_each_segment */ #define __rq_for_each_bio(_bio, rq) \ if ((rq->bio)) \ for (_bio = (rq)->bio; _bio; _bio = _bio->bi_next) #define rq_for_each_segment(bvl, _rq, _iter) \ __rq_for_each_bio(_iter.bio, _rq) \ bio_for_each_segment(bvl, _iter.bio, _iter.i) #define rq_iter_last(rq, _iter) \ (_iter.bio->bi_next == NULL && _iter.i == _iter.bio->bi_vcnt-1) 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_put_request(struct request_queue *, struct request *); extern void blk_end_sync_rq(struct request *rq, int error); extern struct request *blk_get_request(struct request_queue *, int, gfp_t); extern void blk_insert_request(struct request_queue *, struct request *, int, void *); extern void blk_requeue_request(struct request_queue *, struct request *); extern void blk_plug_device(struct request_queue *); extern int blk_remove_plug(struct request_queue *); extern void blk_recount_segments(struct request_queue *, struct bio *); extern int scsi_cmd_ioctl(struct file *, struct request_queue *, struct gendisk *, unsigned int, void __user *); extern int sg_scsi_ioctl(struct file *, struct request_queue *, struct gendisk *, struct scsi_ioctl_command __user *); /* * Temporary export, until SCSI gets fixed up. */ extern int blk_rq_append_bio(struct request_queue *q, struct request *rq, struct bio *bio); /* * A queue has just exitted congestion. Note this in the global counter of * congested queues, and wake up anyone who was waiting for requests to be * put back. */ static inline void blk_clear_queue_congested(struct request_queue *q, int rw) { clear_bdi_congested(&q->backing_dev_info, rw); } /* * A queue has just entered congestion. Flag that in the queue's VM-visible * state flags and increment the global gounter of congested queues. */ static inline void blk_set_queue_congested(struct request_queue *q, int rw) { set_bdi_congested(&q->backing_dev_info, rw); } extern void blk_start_queue(struct request_queue *q); extern void blk_stop_queue(struct request_queue *q); extern void blk_sync_queue(struct request_queue *q); extern void __blk_stop_queue(struct request_queue *q); extern void blk_run_queue(struct request_queue *); extern void blk_start_queueing(struct request_queue *); extern int blk_rq_map_user(struct request_queue *, struct request *, void __user *, unsigned long); extern int blk_rq_unmap_user(struct bio *); extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, unsigned int, gfp_t); extern int blk_rq_map_user_iov(struct request_queue *, struct request *, struct sg_iovec *, int, unsigned int); extern int blk_execute_rq(struct request_queue *, struct gendisk *, struct request *, int); extern void blk_execute_rq_nowait(struct request_queue *, struct gendisk *, struct request *, int, rq_end_io_fn *); extern int blk_verify_command(unsigned char *, int); extern void blk_unplug(struct request_queue *q); static inline struct request_queue *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); } /* * blk_end_request() and friends. * __blk_end_request() and end_request() must be called with * the request queue spinlock acquired. * * Several drivers define their own end_request and call * blk_end_request() for parts of the original function. * This prevents code duplication in drivers. */ extern int blk_end_request(struct request *rq, int error, unsigned int nr_bytes); extern int __blk_end_request(struct request *rq, int error, unsigned int nr_bytes); extern int blk_end_bidi_request(struct request *rq, int error, unsigned int nr_bytes, unsigned int bidi_bytes); extern void end_request(struct request *, int); extern void end_queued_request(struct request *, int); extern void end_dequeued_request(struct request *, int); extern int blk_end_request_callback(struct request *rq, int error, unsigned int nr_bytes, int (drv_callback)(struct request *)); extern void blk_complete_request(struct request *); /* * blk_end_request() takes bytes instead of sectors as a complete size. * blk_rq_bytes() returns bytes left to complete in the entire request. * blk_rq_cur_bytes() returns bytes left to complete in the current segment. */ extern unsigned int blk_rq_bytes(struct request *rq); extern unsigned int blk_rq_cur_bytes(struct request *rq); static inline void blkdev_dequeue_request(struct request *req) { elv_dequeue_request(req->q, req); } /* * Access functions for manipulating queue properties */ extern struct request_queue *blk_init_queue_node(request_fn_proc *rfn, spinlock_t *lock, int node_id); extern struct request_queue *blk_init_queue(request_fn_proc *, spinlock_t *); extern void blk_cleanup_queue(struct request_queue *); extern void blk_queue_make_request(struct request_queue *, make_request_fn *); extern void blk_queue_bounce_limit(struct request_queue *, u64); extern void blk_queue_max_sectors(struct request_queue *, unsigned int); extern void blk_queue_max_phys_segments(struct request_queue *, unsigned short); extern void blk_queue_max_hw_segments(struct request_queue *, unsigned short); extern void blk_queue_max_segment_size(struct request_queue *, unsigned int); extern void blk_queue_hardsect_size(struct request_queue *, unsigned short); extern void blk_queue_stack_limits(struct request_queue *t, struct request_queue *b); extern int blk_queue_dma_drain(struct request_queue *q, dma_drain_needed_fn *dma_drain_needed, void *buf, unsigned int size); extern void blk_queue_segment_boundary(struct request_queue *, unsigned long); extern void blk_queue_prep_rq(struct request_queue *, prep_rq_fn *pfn); extern void blk_queue_merge_bvec(struct request_queue *, merge_bvec_fn *); extern void blk_queue_dma_alignment(struct request_queue *, int); extern void blk_queue_update_dma_alignment(struct request_queue *, int); extern void blk_queue_softirq_done(struct request_queue *, softirq_done_fn *); extern struct backing_dev_info *blk_get_backing_dev_info(struct block_device *bdev); extern int blk_queue_ordered(struct request_queue *, unsigned, prepare_flush_fn *); extern int blk_do_ordered(struct request_queue *, struct request **); extern unsigned blk_ordered_cur_seq(struct request_queue *); extern unsigned blk_ordered_req_seq(struct request *); extern void blk_ordered_complete_seq(struct request_queue *, unsigned, int); extern int blk_rq_map_sg(struct request_queue *, struct request *, struct scatterlist *); extern void blk_dump_rq_flags(struct request *, char *); extern void generic_unplug_device(struct request_queue *); extern void __generic_unplug_device(struct request_queue *); extern long nr_blockdev_pages(void); int blk_get_queue(struct request_queue *); struct request_queue *blk_alloc_queue(gfp_t); struct request_queue *blk_alloc_queue_node(gfp_t, int); extern void blk_put_queue(struct request_queue *); /* * 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)->cmd_flags & REQ_QUEUED) extern int blk_queue_start_tag(struct request_queue *, struct request *); extern struct request *blk_queue_find_tag(struct request_queue *, int); extern void blk_queue_end_tag(struct request_queue *, struct request *); extern int blk_queue_init_tags(struct request_queue *, int, struct blk_queue_tag *); extern void blk_queue_free_tags(struct request_queue *); extern int blk_queue_resize_tags(struct request_queue *, int); extern void blk_queue_invalidate_tags(struct request_queue *); extern struct blk_queue_tag *blk_init_tags(int); extern void blk_free_tags(struct blk_queue_tag *); static inline struct request *blk_map_queue_find_tag(struct blk_queue_tag *bqt, int tag) { if (unlikely(bqt == NULL || tag >= bqt->real_max_depth)) return NULL; return bqt->tag_index[tag]; } extern int blkdev_issue_flush(struct block_device *, sector_t *); #define MAX_PHYS_SEGMENTS 128 #define MAX_HW_SEGMENTS 128 #define SAFE_MAX_SECTORS 255 #define BLK_DEF_MAX_SECTORS 1024 #define MAX_SEGMENT_SIZE 65536 #define blkdev_entry_to_request(entry) list_entry((entry), struct request, queuelist) static inline int queue_hardsect_size(struct request_queue *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(struct request_queue *q) { return q ? q->dma_alignment : 511; } /* 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_work(struct work_struct *work); #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) "-*") #else /* CONFIG_BLOCK */ /* * stubs for when the block layer is configured out */ #define buffer_heads_over_limit 0 static inline long nr_blockdev_pages(void) { return 0; } static inline void exit_io_context(void) { } struct io_context; static inline int put_io_context(struct io_context *ioc) { return 1; } #endif /* CONFIG_BLOCK */ #endif