786 lines
23 KiB
C
786 lines
23 KiB
C
#ifndef _LINUX_BLKDEV_H
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#define _LINUX_BLKDEV_H
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#include <linux/config.h>
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#include <linux/major.h>
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#include <linux/genhd.h>
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#include <linux/list.h>
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#include <linux/timer.h>
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#include <linux/workqueue.h>
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#include <linux/pagemap.h>
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#include <linux/backing-dev.h>
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#include <linux/wait.h>
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#include <linux/mempool.h>
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#include <linux/bio.h>
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#include <linux/module.h>
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#include <linux/stringify.h>
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#include <asm/scatterlist.h>
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struct request_queue;
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typedef struct request_queue request_queue_t;
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struct elevator_queue;
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typedef struct elevator_queue elevator_t;
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struct request_pm_state;
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#define BLKDEV_MIN_RQ 4
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#define BLKDEV_MAX_RQ 128 /* Default maximum */
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/*
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* This is the per-process anticipatory I/O scheduler state.
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*/
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struct as_io_context {
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spinlock_t lock;
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void (*dtor)(struct as_io_context *aic); /* destructor */
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void (*exit)(struct as_io_context *aic); /* called on task exit */
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unsigned long state;
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atomic_t nr_queued; /* queued reads & sync writes */
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atomic_t nr_dispatched; /* number of requests gone to the drivers */
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/* IO History tracking */
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/* Thinktime */
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unsigned long last_end_request;
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unsigned long ttime_total;
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unsigned long ttime_samples;
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unsigned long ttime_mean;
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/* Layout pattern */
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unsigned int seek_samples;
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sector_t last_request_pos;
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u64 seek_total;
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sector_t seek_mean;
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};
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struct cfq_queue;
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struct cfq_io_context {
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/*
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* circular list of cfq_io_contexts belonging to a process io context
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*/
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struct list_head list;
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struct cfq_queue *cfqq;
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void *key;
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struct io_context *ioc;
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unsigned long last_end_request;
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unsigned long last_queue;
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unsigned long ttime_total;
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unsigned long ttime_samples;
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unsigned long ttime_mean;
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void (*dtor)(struct cfq_io_context *);
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void (*exit)(struct cfq_io_context *);
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};
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/*
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* This is the per-process I/O subsystem state. It is refcounted and
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* kmalloc'ed. Currently all fields are modified in process io context
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* (apart from the atomic refcount), so require no locking.
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*/
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struct io_context {
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atomic_t refcount;
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struct task_struct *task;
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int (*set_ioprio)(struct io_context *, unsigned int);
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/*
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* For request batching
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*/
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unsigned long last_waited; /* Time last woken after wait for request */
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int nr_batch_requests; /* Number of requests left in the batch */
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struct as_io_context *aic;
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struct cfq_io_context *cic;
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};
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void put_io_context(struct io_context *ioc);
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void exit_io_context(void);
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struct io_context *current_io_context(gfp_t gfp_flags);
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struct io_context *get_io_context(gfp_t gfp_flags);
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void copy_io_context(struct io_context **pdst, struct io_context **psrc);
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void swap_io_context(struct io_context **ioc1, struct io_context **ioc2);
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struct request;
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typedef void (rq_end_io_fn)(struct request *);
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struct request_list {
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int count[2];
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int starved[2];
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int elvpriv;
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mempool_t *rq_pool;
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wait_queue_head_t wait[2];
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};
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#define BLK_MAX_CDB 16
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/*
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* try to put the fields that are referenced together in the same cacheline
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*/
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struct request {
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struct list_head queuelist; /* looking for ->queue? you must _not_
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* access it directly, use
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* blkdev_dequeue_request! */
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unsigned long flags; /* see REQ_ bits below */
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/* Maintain bio traversal state for part by part I/O submission.
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* hard_* are block layer internals, no driver should touch them!
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*/
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sector_t sector; /* next sector to submit */
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unsigned long nr_sectors; /* no. of sectors left to submit */
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/* no. of sectors left to submit in the current segment */
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unsigned int current_nr_sectors;
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sector_t hard_sector; /* next sector to complete */
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unsigned long hard_nr_sectors; /* no. of sectors left to complete */
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/* no. of sectors left to complete in the current segment */
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unsigned int hard_cur_sectors;
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struct bio *bio;
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struct bio *biotail;
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void *elevator_private;
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unsigned short ioprio;
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int rq_status; /* should split this into a few status bits */
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struct gendisk *rq_disk;
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int errors;
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unsigned long start_time;
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/* Number of scatter-gather DMA addr+len pairs after
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* physical address coalescing is performed.
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*/
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unsigned short nr_phys_segments;
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/* Number of scatter-gather addr+len pairs after
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* physical and DMA remapping hardware coalescing is performed.
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* This is the number of scatter-gather entries the driver
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* will actually have to deal with after DMA mapping is done.
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*/
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unsigned short nr_hw_segments;
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int tag;
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char *buffer;
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int ref_count;
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request_queue_t *q;
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struct request_list *rl;
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struct completion *waiting;
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void *special;
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/*
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* when request is used as a packet command carrier
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*/
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unsigned int cmd_len;
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unsigned char cmd[BLK_MAX_CDB];
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unsigned int data_len;
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void *data;
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unsigned int sense_len;
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void *sense;
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unsigned int timeout;
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/*
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* For Power Management requests
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*/
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struct request_pm_state *pm;
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/*
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* completion callback. end_io_data should be folded in with waiting
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*/
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rq_end_io_fn *end_io;
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void *end_io_data;
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};
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/*
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* first three bits match BIO_RW* bits, important
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*/
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enum rq_flag_bits {
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__REQ_RW, /* not set, read. set, write */
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__REQ_FAILFAST, /* no low level driver retries */
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__REQ_SORTED, /* elevator knows about this request */
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__REQ_SOFTBARRIER, /* may not be passed by ioscheduler */
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__REQ_HARDBARRIER, /* may not be passed by drive either */
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__REQ_CMD, /* is a regular fs rw request */
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__REQ_NOMERGE, /* don't touch this for merging */
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__REQ_STARTED, /* drive already may have started this one */
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__REQ_DONTPREP, /* don't call prep for this one */
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__REQ_QUEUED, /* uses queueing */
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__REQ_ELVPRIV, /* elevator private data attached */
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/*
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* for ATA/ATAPI devices
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*/
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__REQ_PC, /* packet command (special) */
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__REQ_BLOCK_PC, /* queued down pc from block layer */
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__REQ_SENSE, /* sense retrival */
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__REQ_FAILED, /* set if the request failed */
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__REQ_QUIET, /* don't worry about errors */
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__REQ_SPECIAL, /* driver suplied command */
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__REQ_DRIVE_CMD,
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__REQ_DRIVE_TASK,
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__REQ_DRIVE_TASKFILE,
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__REQ_PREEMPT, /* set for "ide_preempt" requests */
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__REQ_PM_SUSPEND, /* suspend request */
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__REQ_PM_RESUME, /* resume request */
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__REQ_PM_SHUTDOWN, /* shutdown request */
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__REQ_BAR_PREFLUSH, /* barrier pre-flush done */
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__REQ_BAR_POSTFLUSH, /* barrier post-flush */
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__REQ_BAR_FLUSH, /* rq is the flush request */
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__REQ_NR_BITS, /* stops here */
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};
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#define REQ_RW (1 << __REQ_RW)
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#define REQ_FAILFAST (1 << __REQ_FAILFAST)
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#define REQ_SORTED (1 << __REQ_SORTED)
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#define REQ_SOFTBARRIER (1 << __REQ_SOFTBARRIER)
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#define REQ_HARDBARRIER (1 << __REQ_HARDBARRIER)
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#define REQ_CMD (1 << __REQ_CMD)
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#define REQ_NOMERGE (1 << __REQ_NOMERGE)
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#define REQ_STARTED (1 << __REQ_STARTED)
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#define REQ_DONTPREP (1 << __REQ_DONTPREP)
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#define REQ_QUEUED (1 << __REQ_QUEUED)
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#define REQ_ELVPRIV (1 << __REQ_ELVPRIV)
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#define REQ_PC (1 << __REQ_PC)
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#define REQ_BLOCK_PC (1 << __REQ_BLOCK_PC)
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#define REQ_SENSE (1 << __REQ_SENSE)
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#define REQ_FAILED (1 << __REQ_FAILED)
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#define REQ_QUIET (1 << __REQ_QUIET)
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#define REQ_SPECIAL (1 << __REQ_SPECIAL)
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#define REQ_DRIVE_CMD (1 << __REQ_DRIVE_CMD)
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#define REQ_DRIVE_TASK (1 << __REQ_DRIVE_TASK)
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#define REQ_DRIVE_TASKFILE (1 << __REQ_DRIVE_TASKFILE)
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#define REQ_PREEMPT (1 << __REQ_PREEMPT)
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#define REQ_PM_SUSPEND (1 << __REQ_PM_SUSPEND)
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#define REQ_PM_RESUME (1 << __REQ_PM_RESUME)
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#define REQ_PM_SHUTDOWN (1 << __REQ_PM_SHUTDOWN)
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#define REQ_BAR_PREFLUSH (1 << __REQ_BAR_PREFLUSH)
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#define REQ_BAR_POSTFLUSH (1 << __REQ_BAR_POSTFLUSH)
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#define REQ_BAR_FLUSH (1 << __REQ_BAR_FLUSH)
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/*
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* State information carried for REQ_PM_SUSPEND and REQ_PM_RESUME
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* requests. Some step values could eventually be made generic.
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*/
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struct request_pm_state
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{
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/* PM state machine step value, currently driver specific */
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int pm_step;
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/* requested PM state value (S1, S2, S3, S4, ...) */
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u32 pm_state;
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void* data; /* for driver use */
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};
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#include <linux/elevator.h>
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typedef int (merge_request_fn) (request_queue_t *, struct request *,
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struct bio *);
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typedef int (merge_requests_fn) (request_queue_t *, struct request *,
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struct request *);
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typedef void (request_fn_proc) (request_queue_t *q);
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typedef int (make_request_fn) (request_queue_t *q, struct bio *bio);
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typedef int (prep_rq_fn) (request_queue_t *, struct request *);
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typedef void (unplug_fn) (request_queue_t *);
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struct bio_vec;
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typedef int (merge_bvec_fn) (request_queue_t *, struct bio *, struct bio_vec *);
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typedef void (activity_fn) (void *data, int rw);
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typedef int (issue_flush_fn) (request_queue_t *, struct gendisk *, sector_t *);
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typedef int (prepare_flush_fn) (request_queue_t *, struct request *);
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typedef void (end_flush_fn) (request_queue_t *, struct request *);
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enum blk_queue_state {
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Queue_down,
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Queue_up,
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};
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struct blk_queue_tag {
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struct request **tag_index; /* map of busy tags */
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unsigned long *tag_map; /* bit map of free/busy tags */
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struct list_head busy_list; /* fifo list of busy tags */
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int busy; /* current depth */
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int max_depth; /* what we will send to device */
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int real_max_depth; /* what the array can hold */
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atomic_t refcnt; /* map can be shared */
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};
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struct request_queue
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{
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/*
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* Together with queue_head for cacheline sharing
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*/
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struct list_head queue_head;
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struct request *last_merge;
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elevator_t *elevator;
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/*
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* the queue request freelist, one for reads and one for writes
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*/
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struct request_list rq;
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request_fn_proc *request_fn;
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merge_request_fn *back_merge_fn;
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merge_request_fn *front_merge_fn;
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merge_requests_fn *merge_requests_fn;
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make_request_fn *make_request_fn;
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prep_rq_fn *prep_rq_fn;
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unplug_fn *unplug_fn;
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merge_bvec_fn *merge_bvec_fn;
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activity_fn *activity_fn;
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issue_flush_fn *issue_flush_fn;
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prepare_flush_fn *prepare_flush_fn;
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end_flush_fn *end_flush_fn;
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/*
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* Dispatch queue sorting
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*/
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sector_t end_sector;
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struct request *boundary_rq;
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/*
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* Auto-unplugging state
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*/
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struct timer_list unplug_timer;
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int unplug_thresh; /* After this many requests */
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unsigned long unplug_delay; /* After this many jiffies */
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struct work_struct unplug_work;
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struct backing_dev_info backing_dev_info;
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/*
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* The queue owner gets to use this for whatever they like.
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* ll_rw_blk doesn't touch it.
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*/
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void *queuedata;
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void *activity_data;
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/*
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* queue needs bounce pages for pages above this limit
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*/
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unsigned long bounce_pfn;
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gfp_t bounce_gfp;
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/*
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* various queue flags, see QUEUE_* below
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*/
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unsigned long queue_flags;
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/*
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* protects queue structures from reentrancy. ->__queue_lock should
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* _never_ be used directly, it is queue private. always use
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* ->queue_lock.
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*/
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spinlock_t __queue_lock;
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spinlock_t *queue_lock;
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/*
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* queue kobject
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*/
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struct kobject kobj;
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/*
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* queue settings
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*/
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unsigned long nr_requests; /* Max # of requests */
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unsigned int nr_congestion_on;
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unsigned int nr_congestion_off;
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unsigned int nr_batching;
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unsigned short max_sectors;
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unsigned short max_hw_sectors;
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unsigned short max_phys_segments;
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unsigned short max_hw_segments;
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unsigned short hardsect_size;
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unsigned int max_segment_size;
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unsigned long seg_boundary_mask;
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unsigned int dma_alignment;
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struct blk_queue_tag *queue_tags;
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atomic_t refcnt;
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unsigned int in_flight;
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/*
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* sg stuff
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*/
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unsigned int sg_timeout;
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unsigned int sg_reserved_size;
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int node;
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/*
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* reserved for flush operations
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*/
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struct request *flush_rq;
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unsigned char ordered;
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};
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enum {
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QUEUE_ORDERED_NONE,
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QUEUE_ORDERED_TAG,
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QUEUE_ORDERED_FLUSH,
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};
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#define RQ_INACTIVE (-1)
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#define RQ_ACTIVE 1
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#define RQ_SCSI_BUSY 0xffff
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#define RQ_SCSI_DONE 0xfffe
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#define RQ_SCSI_DISCONNECTING 0xffe0
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#define QUEUE_FLAG_CLUSTER 0 /* cluster several segments into 1 */
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#define QUEUE_FLAG_QUEUED 1 /* uses generic tag queueing */
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#define QUEUE_FLAG_STOPPED 2 /* queue is stopped */
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#define QUEUE_FLAG_READFULL 3 /* write queue has been filled */
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#define QUEUE_FLAG_WRITEFULL 4 /* read queue has been filled */
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#define QUEUE_FLAG_DEAD 5 /* queue being torn down */
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#define QUEUE_FLAG_REENTER 6 /* Re-entrancy avoidance */
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#define QUEUE_FLAG_PLUGGED 7 /* queue is plugged */
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#define QUEUE_FLAG_ELVSWITCH 8 /* don't use elevator, just do FIFO */
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#define QUEUE_FLAG_FLUSH 9 /* doing barrier flush sequence */
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#define blk_queue_plugged(q) test_bit(QUEUE_FLAG_PLUGGED, &(q)->queue_flags)
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#define blk_queue_tagged(q) test_bit(QUEUE_FLAG_QUEUED, &(q)->queue_flags)
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#define blk_queue_stopped(q) test_bit(QUEUE_FLAG_STOPPED, &(q)->queue_flags)
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#define blk_queue_flushing(q) test_bit(QUEUE_FLAG_FLUSH, &(q)->queue_flags)
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#define blk_fs_request(rq) ((rq)->flags & REQ_CMD)
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#define blk_pc_request(rq) ((rq)->flags & REQ_BLOCK_PC)
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#define blk_noretry_request(rq) ((rq)->flags & REQ_FAILFAST)
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#define blk_rq_started(rq) ((rq)->flags & REQ_STARTED)
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#define blk_account_rq(rq) (blk_rq_started(rq) && blk_fs_request(rq))
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#define blk_pm_suspend_request(rq) ((rq)->flags & REQ_PM_SUSPEND)
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#define blk_pm_resume_request(rq) ((rq)->flags & REQ_PM_RESUME)
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#define blk_pm_request(rq) \
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((rq)->flags & (REQ_PM_SUSPEND | REQ_PM_RESUME))
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#define blk_sorted_rq(rq) ((rq)->flags & REQ_SORTED)
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#define blk_barrier_rq(rq) ((rq)->flags & REQ_HARDBARRIER)
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#define blk_barrier_preflush(rq) ((rq)->flags & REQ_BAR_PREFLUSH)
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#define blk_barrier_postflush(rq) ((rq)->flags & REQ_BAR_POSTFLUSH)
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#define list_entry_rq(ptr) list_entry((ptr), struct request, queuelist)
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#define rq_data_dir(rq) ((rq)->flags & 1)
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static inline int blk_queue_full(struct request_queue *q, int rw)
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{
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if (rw == READ)
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return test_bit(QUEUE_FLAG_READFULL, &q->queue_flags);
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return test_bit(QUEUE_FLAG_WRITEFULL, &q->queue_flags);
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}
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static inline void blk_set_queue_full(struct request_queue *q, int rw)
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{
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if (rw == READ)
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set_bit(QUEUE_FLAG_READFULL, &q->queue_flags);
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else
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set_bit(QUEUE_FLAG_WRITEFULL, &q->queue_flags);
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}
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static inline void blk_clear_queue_full(struct request_queue *q, int rw)
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{
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if (rw == READ)
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clear_bit(QUEUE_FLAG_READFULL, &q->queue_flags);
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else
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clear_bit(QUEUE_FLAG_WRITEFULL, &q->queue_flags);
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}
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/*
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* 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, gfp_t);
|
|
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, gfp_t);
|
|
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);
|
|
|
|
int blk_get_queue(request_queue_t *);
|
|
request_queue_t *blk_alloc_queue(gfp_t);
|
|
request_queue_t *blk_alloc_queue_node(gfp_t, 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
|