From 4aff5e2333c9a1609662f2091f55c3f6fffdad36 Mon Sep 17 00:00:00 2001 From: Jens Axboe Date: Thu, 10 Aug 2006 08:44:47 +0200 Subject: [PATCH] Split struct request ->flags into two parts Right now ->flags is a bit of a mess: some are request types, and others are just modifiers. Clean this up by splitting it into ->cmd_type and ->cmd_flags. This allows introduction of generic Linux block message types, useful for sending generic Linux commands to block devices. Signed-off-by: Jens Axboe --- include/linux/blkdev.h | 180 +++++++++++++++++++++++++++---------------------- 1 file changed, 99 insertions(+), 81 deletions(-) (limited to 'include/linux/blkdev.h') diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h index cfde8b3ee91..b2a412cf468 100644 --- a/include/linux/blkdev.h +++ b/include/linux/blkdev.h @@ -120,6 +120,86 @@ 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_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 BLK_MAX_CDB 16 /* @@ -129,7 +209,8 @@ struct request { struct list_head queuelist; struct list_head donelist; - unsigned long flags; /* see REQ_ bits below */ + 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! @@ -202,73 +283,7 @@ struct request { }; /* - * 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 @@ -490,25 +505,28 @@ 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) static inline int blk_queue_full(struct request_queue *q, int rw) { @@ -541,7 +559,7 @@ 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))) + (!((rq)->cmd_flags & RQ_NOMERGE_FLAGS) && blk_fs_request((rq))) /* * noop, requests are automagically marked as active/inactive by I/O @@ -737,7 +755,7 @@ 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 *); -- cgit v1.2.3