diff options
Diffstat (limited to 'include/linux/blkdev.h')
| -rw-r--r-- | include/linux/blkdev.h | 345 |
1 files changed, 186 insertions, 159 deletions
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index c773ee545eb..26f7856ff81 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -1,6 +1,7 @@ #ifndef _LINUX_BLKDEV_H #define _LINUX_BLKDEV_H +#include <linux/sched.h> #include <linux/major.h> #include <linux/genhd.h> #include <linux/list.h> @@ -16,6 +17,22 @@ #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; @@ -90,7 +107,7 @@ struct io_context { atomic_t refcount; struct task_struct *task; - int (*set_ioprio)(struct io_context *, unsigned int); + unsigned int ioprio_changed; /* * For request batching @@ -104,8 +121,7 @@ struct io_context { 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); @@ -120,6 +136,90 @@ struct request_list { 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, +}; + +/* + * 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 /* @@ -129,30 +229,46 @@ struct request { 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; @@ -170,15 +286,13 @@ struct request { 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 @@ -195,80 +309,14 @@ struct request { 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 @@ -417,9 +465,9 @@ struct request_queue 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 */ @@ -432,9 +480,6 @@ struct request_queue 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 */ @@ -490,25 +535,34 @@ enum { #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) { @@ -541,13 +595,7 @@ static inline void blk_clear_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 @@ -586,11 +634,6 @@ static inline void blk_queue_bounce(request_queue_t *q, struct bio **bio) 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); @@ -612,6 +655,7 @@ 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); @@ -655,16 +699,6 @@ extern void end_that_request_last(struct request *, 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, @@ -679,21 +713,6 @@ static inline void blkdev_dequeue_request(struct request *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 */ extern request_queue_t *blk_init_queue_node(request_fn_proc *rfn, @@ -737,7 +756,7 @@ extern void blk_put_queue(request_queue_t *); */ #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 *); @@ -750,6 +769,14 @@ extern struct blk_queue_tag *blk_init_tags(int); 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 *); @@ -787,14 +814,6 @@ static inline int queue_dma_alignment(request_queue_t *q) 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) { @@ -824,24 +843,32 @@ 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) "-*") +#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 |