#ifndef _LINUX_BLKDEV_H
#define _LINUX_BLKDEV_H
+#include <linux/sched.h>
#include <linux/major.h>
#include <linux/genhd.h>
#include <linux/list.h>
#include <asm/scatterlist.h>
+#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
+
+#ifdef CONFIG_BLOCK
+
struct scsi_ioctl_command;
struct request_queue;
atomic_t refcount;
struct task_struct *task;
- int (*set_ioprio)(struct io_context *, unsigned int);
+ unsigned int ioprio_changed;
/*
* For request batching
void put_io_context(struct io_context *ioc);
void exit_io_context(void);
-struct io_context *current_io_context(gfp_t gfp_flags);
-struct io_context *get_io_context(gfp_t gfp_flags);
+struct io_context *get_io_context(gfp_t gfp_flags, int node);
void copy_io_context(struct io_context **pdst, struct io_context **psrc);
void swap_io_context(struct io_context **ioc1, struct io_context **ioc2);
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_CMD,
+ REQ_TYPE_ATA_TASK,
+ 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
/*
struct list_head queuelist;
struct list_head donelist;
- unsigned long flags; /* see REQ_ bits below */
+ request_queue_t *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;
- 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;
+ 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 *completion_data;
+ void *elevator_private2;
- int rq_status; /* should split this into a few status bits */
- int errors;
struct gendisk *rq_disk;
unsigned long start_time;
unsigned short ioprio;
+ void *special;
+ char *buffer;
+
int tag;
+ int errors;
int ref_count;
- request_queue_t *q;
- struct request_list *rl;
-
- struct completion *waiting;
- void *special;
- char *buffer;
/*
* when request is used as a packet command carrier
int retries;
/*
- * completion callback. end_io_data should be folded in with waiting
+ * completion callback.
*/
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_FUA, /* forced unit access */
- __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 */
- __REQ_ELVPRIV, /* elevator private data attached */
- /*
- * 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_ORDERED_COLOR, /* is before or after barrier */
- __REQ_RW_SYNC, /* request is sync (O_DIRECT) */
- __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_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_ELVPRIV (1 << __REQ_ELVPRIV)
-#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_ORDERED_COLOR (1 << __REQ_ORDERED_COLOR)
-#define REQ_RW_SYNC (1 << __REQ_RW_SYNC)
-
-/*
- * State information carried for REQ_PM_SUSPEND and REQ_PM_RESUME
+ * 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
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
*/
struct mutex sysfs_lock;
};
-#define RQ_INACTIVE (-1)
-#define RQ_ACTIVE 1
-
#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 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)->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_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)->flags & REQ_PM_SUSPEND)
-#define blk_pm_resume_request(rq) ((rq)->flags & REQ_PM_RESUME)
+#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) \
- ((rq)->flags & (REQ_PM_SUSPEND | REQ_PM_RESUME))
+ (blk_pm_suspend_request(rq) || blk_pm_resume_request(rq))
-#define blk_sorted_rq(rq) ((rq)->flags & REQ_SORTED)
-#define blk_barrier_rq(rq) ((rq)->flags & REQ_HARDBARRIER)
-#define blk_fua_rq(rq) ((rq)->flags & REQ_FUA)
+#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 list_entry_rq(ptr) list_entry((ptr), struct request, queuelist)
-#define rq_data_dir(rq) ((rq)->flags & 1)
+#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)
{
#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)
+ (!((rq)->cmd_flags & RQ_NOMERGE_FLAGS) && blk_fs_request((rq)))
/*
* q->prep_rq_fn return values
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 int scsi_cmd_ioctl(struct file *, struct gendisk *, unsigned int, void __user *);
extern int sg_scsi_ioctl(struct file *, struct request_queue *,
struct gendisk *, struct scsi_ioctl_command __user *);
+extern void blk_clear_queue_congested(request_queue_t *q, int rw);
+extern void blk_set_queue_congested(request_queue_t *q, int rw);
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_start_queueing(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 void end_request(struct request *req, int uptodate);
extern void blk_complete_request(struct request *);
-static inline int rq_all_done(struct request *rq, unsigned int nr_bytes)
-{
- if (blk_fs_request(rq))
- return (nr_bytes >= (rq->hard_nr_sectors << 9));
- else if (blk_pc_request(rq))
- return nr_bytes >= rq->data_len;
-
- return 0;
-}
-
/*
* end_that_request_first/chunk() takes an uptodate argument. we account
* any value <= as an io error. 0 means -EIO for compatability reasons,
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->nr_sorted--;
-
- 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
*/
*/
#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)
+#define blk_rq_tagged(rq) ((rq)->cmd_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 void blk_free_tags(struct blk_queue_tag *);
extern void blk_congestion_end(int rw);
+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 void blk_rq_bio_prep(request_queue_t *, struct request *, struct bio *);
extern int blkdev_issue_flush(struct block_device *, sector_t *);
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)
{
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) "-*")
+#else /* CONFIG_BLOCK */
+/*
+ * stubs for when the block layer is configured out
+ */
+#define buffer_heads_over_limit 0
+
+static inline long blk_congestion_wait(int rw, long timeout)
+{
+ return io_schedule_timeout(timeout);
+}
+
+static inline long nr_blockdev_pages(void)
+{
+ return 0;
+}
+
+static inline void exit_io_context(void)
+{
+}
+
+#endif /* CONFIG_BLOCK */
+
#endif
Code Review / linux-2.6.git / blobdiff