include/linux/blktrace_api.h - fp2-dev/kernel/msm - Gitiles

 #ifndef BLKTRACE_H
 #define BLKTRACE_H

 #include <linux/blkdev.h>
 #include <linux/relay.h>

 /*
  * Trace categories
  */
 enum blktrace_cat {
 	BLK_TC_READ	= 1 << 0,	/* reads */
 	BLK_TC_WRITE	= 1 << 1,	/* writes */
 	BLK_TC_BARRIER	= 1 << 2,	/* barrier */
 	BLK_TC_SYNC	= 1 << 3,	/* sync IO */
 	BLK_TC_QUEUE	= 1 << 4,	/* queueing/merging */
 	BLK_TC_REQUEUE	= 1 << 5,	/* requeueing */
 	BLK_TC_ISSUE	= 1 << 6,	/* issue */
 	BLK_TC_COMPLETE	= 1 << 7,	/* completions */
 	BLK_TC_FS	= 1 << 8,	/* fs requests */
 	BLK_TC_PC	= 1 << 9,	/* pc requests */
 	BLK_TC_NOTIFY	= 1 << 10,	/* special message */
 	BLK_TC_AHEAD	= 1 << 11,	/* readahead */
 	BLK_TC_META	= 1 << 12,	/* metadata */

 	BLK_TC_END	= 1 << 15,	/* only 16-bits, reminder */
 };

 #define BLK_TC_SHIFT		(16)
 #define BLK_TC_ACT(act)		((act) << BLK_TC_SHIFT)

 /*
  * Basic trace actions
  */
 enum blktrace_act {
 	__BLK_TA_QUEUE = 1,		/* queued */
 	__BLK_TA_BACKMERGE,		/* back merged to existing rq */
 	__BLK_TA_FRONTMERGE,		/* front merge to existing rq */
 	__BLK_TA_GETRQ,			/* allocated new request */
 	__BLK_TA_SLEEPRQ,		/* sleeping on rq allocation */
 	__BLK_TA_REQUEUE,		/* request requeued */
 	__BLK_TA_ISSUE,			/* sent to driver */
 	__BLK_TA_COMPLETE,		/* completed by driver */
 	__BLK_TA_PLUG,			/* queue was plugged */
 	__BLK_TA_UNPLUG_IO,		/* queue was unplugged by io */
 	__BLK_TA_UNPLUG_TIMER,		/* queue was unplugged by timer */
 	__BLK_TA_INSERT,		/* insert request */
 	__BLK_TA_SPLIT,			/* bio was split */
 	__BLK_TA_BOUNCE,		/* bio was bounced */
 	__BLK_TA_REMAP,			/* bio was remapped */
 };

 /*
  * Notify events.
  */
 enum blktrace_notify {
 	__BLK_TN_PROCESS = 0,		/* establish pid/name mapping */
 	__BLK_TN_TIMESTAMP,		/* include system clock */
 	__BLK_TN_MESSAGE,		/* Character string message */
 };


 /*
  * Trace actions in full. Additionally, read or write is masked
  */
 #define BLK_TA_QUEUE		(__BLK_TA_QUEUE | BLK_TC_ACT(BLK_TC_QUEUE))
 #define BLK_TA_BACKMERGE	(__BLK_TA_BACKMERGE | BLK_TC_ACT(BLK_TC_QUEUE))
 #define BLK_TA_FRONTMERGE	(__BLK_TA_FRONTMERGE | BLK_TC_ACT(BLK_TC_QUEUE))
 #define	BLK_TA_GETRQ		(__BLK_TA_GETRQ | BLK_TC_ACT(BLK_TC_QUEUE))
 #define	BLK_TA_SLEEPRQ		(__BLK_TA_SLEEPRQ | BLK_TC_ACT(BLK_TC_QUEUE))
 #define	BLK_TA_REQUEUE		(__BLK_TA_REQUEUE | BLK_TC_ACT(BLK_TC_REQUEUE))
 #define BLK_TA_ISSUE		(__BLK_TA_ISSUE | BLK_TC_ACT(BLK_TC_ISSUE))
 #define BLK_TA_COMPLETE		(__BLK_TA_COMPLETE| BLK_TC_ACT(BLK_TC_COMPLETE))
 #define BLK_TA_PLUG		(__BLK_TA_PLUG | BLK_TC_ACT(BLK_TC_QUEUE))
 #define BLK_TA_UNPLUG_IO	(__BLK_TA_UNPLUG_IO | BLK_TC_ACT(BLK_TC_QUEUE))
 #define BLK_TA_UNPLUG_TIMER	(__BLK_TA_UNPLUG_TIMER | BLK_TC_ACT(BLK_TC_QUEUE))
 #define BLK_TA_INSERT		(__BLK_TA_INSERT | BLK_TC_ACT(BLK_TC_QUEUE))
 #define BLK_TA_SPLIT		(__BLK_TA_SPLIT)
 #define BLK_TA_BOUNCE		(__BLK_TA_BOUNCE)
 #define BLK_TA_REMAP		(__BLK_TA_REMAP | BLK_TC_ACT(BLK_TC_QUEUE))

 #define BLK_TN_PROCESS		(__BLK_TN_PROCESS | BLK_TC_ACT(BLK_TC_NOTIFY))
 #define BLK_TN_TIMESTAMP	(__BLK_TN_TIMESTAMP | BLK_TC_ACT(BLK_TC_NOTIFY))
 #define BLK_TN_MESSAGE		(__BLK_TN_MESSAGE | BLK_TC_ACT(BLK_TC_NOTIFY))

 #define BLK_IO_TRACE_MAGIC	0x65617400
 #define BLK_IO_TRACE_VERSION	0x07

 /*
  * The trace itself
  */
 struct blk_io_trace {
 	u32 magic;		/* MAGIC << 8 | version */
 	u32 sequence;		/* event number */
 	u64 time;		/* in microseconds */
 	u64 sector;		/* disk offset */
 	u32 bytes;		/* transfer length */
 	u32 action;		/* what happened */
 	u32 pid;		/* who did it */
 	u32 device;		/* device number */
 	u32 cpu;		/* on what cpu did it happen */
 	u16 error;		/* completion error */
 	u16 pdu_len;		/* length of data after this trace */
 };

 /*
  * The remap event
  */
 struct blk_io_trace_remap {
 	__be32 device;
 	__be32 device_from;
 	__be64 sector;
 };

 enum {
 	Blktrace_setup = 1,
 	Blktrace_running,
 	Blktrace_stopped,
 };

 struct blk_trace {
 	int trace_state;
 	struct rchan *rchan;
 	unsigned long *sequence;
 	unsigned char *msg_data;
 	u16 act_mask;
 	u64 start_lba;
 	u64 end_lba;
 	u32 pid;
 	u32 dev;
 	struct dentry *dir;
 	struct dentry *dropped_file;
 	atomic_t dropped;
 };

 /*
  * User setup structure passed with BLKTRACESTART
  */
 struct blk_user_trace_setup {
 	char name[BDEVNAME_SIZE];	/* output */
 	u16 act_mask;			/* input */
 	u32 buf_size;			/* input */
 	u32 buf_nr;			/* input */
 	u64 start_lba;
 	u64 end_lba;
 	u32 pid;
 };

 #ifdef __KERNEL__
 #if defined(CONFIG_BLK_DEV_IO_TRACE)
 extern int blk_trace_ioctl(struct block_device *, unsigned, char __user *);
 extern void blk_trace_shutdown(struct request_queue *);
 extern void __blk_add_trace(struct blk_trace *, sector_t, int, int, u32, int, int, void *);
 extern int do_blk_trace_setup(struct request_queue *q,
 	char *name, dev_t dev, struct blk_user_trace_setup *buts);
 extern void __trace_note_message(struct blk_trace *, const char *fmt, ...);

 /**
  * blk_add_trace_msg - Add a (simple) message to the blktrace stream
  * @q:		queue the io is for
  * @fmt:	format to print message in
  * args...	Variable argument list for format
  *
  * Description:
  *     Records a (simple) message onto the blktrace stream.
  *
  *     NOTE: BLK_TN_MAX_MSG characters are output at most.
  *     NOTE: Can not use 'static inline' due to presence of var args...
  *
  **/
 #define blk_add_trace_msg(q, fmt, ...)					\
 	do {								\
 		struct blk_trace *bt = (q)->blk_trace;			\
 		if (unlikely(bt))					\
 			__trace_note_message(bt, fmt, ##__VA_ARGS__);	\
 	} while (0)
 #define BLK_TN_MAX_MSG		128

 /**
  * blk_add_trace_rq - Add a trace for a request oriented action
  * @q:		queue the io is for
  * @rq:		the source request
  * @what:	the action
  *
  * Description:
  *     Records an action against a request. Will log the bio offset + size.
  *
  **/
 static inline void blk_add_trace_rq(struct request_queue *q, struct request *rq,
 				    u32 what)
 {
 	struct blk_trace *bt = q->blk_trace;
 	int rw = rq->cmd_flags & 0x03;

 	if (likely(!bt))
 		return;

 	if (blk_pc_request(rq)) {
 		what |= BLK_TC_ACT(BLK_TC_PC);
 		__blk_add_trace(bt, 0, rq->data_len, rw, what, rq->errors, sizeof(rq->cmd), rq->cmd);
 	} else  {
 		what |= BLK_TC_ACT(BLK_TC_FS);
 		__blk_add_trace(bt, rq->hard_sector, rq->hard_nr_sectors << 9, rw, what, rq->errors, 0, NULL);
 	}
 }

 /**
  * blk_add_trace_bio - Add a trace for a bio oriented action
  * @q:		queue the io is for
  * @bio:	the source bio
  * @what:	the action
  *
  * Description:
  *     Records an action against a bio. Will log the bio offset + size.
  *
  **/
 static inline void blk_add_trace_bio(struct request_queue *q, struct bio *bio,
 				     u32 what)
 {
 	struct blk_trace *bt = q->blk_trace;

 	if (likely(!bt))
 		return;

 	__blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, !bio_flagged(bio, BIO_UPTODATE), 0, NULL);
 }

 /**
  * blk_add_trace_generic - Add a trace for a generic action
  * @q:		queue the io is for
  * @bio:	the source bio
  * @rw:		the data direction
  * @what:	the action
  *
  * Description:
  *     Records a simple trace
  *
  **/
 static inline void blk_add_trace_generic(struct request_queue *q,
 					 struct bio *bio, int rw, u32 what)
 {
 	struct blk_trace *bt = q->blk_trace;

 	if (likely(!bt))
 		return;

 	if (bio)
 		blk_add_trace_bio(q, bio, what);
 	else
 		__blk_add_trace(bt, 0, 0, rw, what, 0, 0, NULL);
 }

 /**
  * blk_add_trace_pdu_int - Add a trace for a bio with an integer payload
  * @q:		queue the io is for
  * @what:	the action
  * @bio:	the source bio
  * @pdu:	the integer payload
  *
  * Description:
  *     Adds a trace with some integer payload. This might be an unplug
  *     option given as the action, with the depth at unplug time given
  *     as the payload
  *
  **/
 static inline void blk_add_trace_pdu_int(struct request_queue *q, u32 what,
 					 struct bio *bio, unsigned int pdu)
 {
 	struct blk_trace *bt = q->blk_trace;
 	__be64 rpdu = cpu_to_be64(pdu);

 	if (likely(!bt))
 		return;

 	if (bio)
 		__blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, !bio_flagged(bio, BIO_UPTODATE), sizeof(rpdu), &rpdu);
 	else
 		__blk_add_trace(bt, 0, 0, 0, what, 0, sizeof(rpdu), &rpdu);
 }

 /**
  * blk_add_trace_remap - Add a trace for a remap operation
  * @q:		queue the io is for
  * @bio:	the source bio
  * @dev:	target device
  * @from:	source sector
  * @to:		target sector
  *
  * Description:
  *     Device mapper or raid target sometimes need to split a bio because
  *     it spans a stripe (or similar). Add a trace for that action.
  *
  **/
 static inline void blk_add_trace_remap(struct request_queue *q, struct bio *bio,
 				       dev_t dev, sector_t from, sector_t to)
 {
 	struct blk_trace *bt = q->blk_trace;
 	struct blk_io_trace_remap r;

 	if (likely(!bt))
 		return;

 	r.device = cpu_to_be32(dev);
 	r.device_from = cpu_to_be32(bio->bi_bdev->bd_dev);
 	r.sector = cpu_to_be64(to);

 	__blk_add_trace(bt, from, bio->bi_size, bio->bi_rw, BLK_TA_REMAP, !bio_flagged(bio, BIO_UPTODATE), sizeof(r), &r);
 }

 extern int blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
 			   char __user *arg);
 extern int blk_trace_startstop(struct request_queue *q, int start);
 extern int blk_trace_remove(struct request_queue *q);

 #else /* !CONFIG_BLK_DEV_IO_TRACE */
 #define blk_trace_ioctl(bdev, cmd, arg)		(-ENOTTY)
 #define blk_trace_shutdown(q)			do { } while (0)
 #define blk_add_trace_rq(q, rq, what)		do { } while (0)
 #define blk_add_trace_bio(q, rq, what)		do { } while (0)
 #define blk_add_trace_generic(q, rq, rw, what)	do { } while (0)
 #define blk_add_trace_pdu_int(q, what, bio, pdu)	do { } while (0)
 #define blk_add_trace_remap(q, bio, dev, f, t)	do {} while (0)
 #define do_blk_trace_setup(q, name, dev, buts)	(-ENOTTY)
 #define blk_trace_setup(q, name, dev, arg)	(-ENOTTY)
 #define blk_trace_startstop(q, start)		(-ENOTTY)
 #define blk_trace_remove(q)			(-ENOTTY)
 #define blk_add_trace_msg(q, fmt, ...)		do { } while (0)

 #endif /* CONFIG_BLK_DEV_IO_TRACE */
 #endif /* __KERNEL__ */
 #endif
	#ifndef BLKTRACE_H
	#define BLKTRACE_H

	#include <linux/blkdev.h>
	#include <linux/relay.h>

	/*
	* Trace categories
	*/
	enum blktrace_cat {
	BLK_TC_READ = 1 << 0, /* reads */
	BLK_TC_WRITE = 1 << 1, /* writes */
	BLK_TC_BARRIER = 1 << 2, /* barrier */
	BLK_TC_SYNC = 1 << 3, /* sync IO */
	BLK_TC_QUEUE = 1 << 4, /* queueing/merging */
	BLK_TC_REQUEUE = 1 << 5, /* requeueing */
	BLK_TC_ISSUE = 1 << 6, /* issue */
	BLK_TC_COMPLETE = 1 << 7, /* completions */
	BLK_TC_FS = 1 << 8, /* fs requests */
	BLK_TC_PC = 1 << 9, /* pc requests */
	BLK_TC_NOTIFY = 1 << 10, /* special message */
	BLK_TC_AHEAD = 1 << 11, /* readahead */
	BLK_TC_META = 1 << 12, /* metadata */

	BLK_TC_END = 1 << 15, /* only 16-bits, reminder */
	};

	#define BLK_TC_SHIFT (16)
	#define BLK_TC_ACT(act) ((act) << BLK_TC_SHIFT)

	/*
	* Basic trace actions
	*/
	enum blktrace_act {
	__BLK_TA_QUEUE = 1, /* queued */
	__BLK_TA_BACKMERGE, /* back merged to existing rq */
	__BLK_TA_FRONTMERGE, /* front merge to existing rq */
	__BLK_TA_GETRQ, /* allocated new request */
	__BLK_TA_SLEEPRQ, /* sleeping on rq allocation */
	__BLK_TA_REQUEUE, /* request requeued */
	__BLK_TA_ISSUE, /* sent to driver */
	__BLK_TA_COMPLETE, /* completed by driver */
	__BLK_TA_PLUG, /* queue was plugged */
	__BLK_TA_UNPLUG_IO, /* queue was unplugged by io */
	__BLK_TA_UNPLUG_TIMER, /* queue was unplugged by timer */
	__BLK_TA_INSERT, /* insert request */
	__BLK_TA_SPLIT, /* bio was split */
	__BLK_TA_BOUNCE, /* bio was bounced */
	__BLK_TA_REMAP, /* bio was remapped */
	};

	/*
	* Notify events.
	*/
	enum blktrace_notify {
	__BLK_TN_PROCESS = 0, /* establish pid/name mapping */
	__BLK_TN_TIMESTAMP, /* include system clock */
	__BLK_TN_MESSAGE, /* Character string message */
	};


	/*
	* Trace actions in full. Additionally, read or write is masked
	*/
	#define BLK_TA_QUEUE (__BLK_TA_QUEUE \| BLK_TC_ACT(BLK_TC_QUEUE))
	#define BLK_TA_BACKMERGE (__BLK_TA_BACKMERGE \| BLK_TC_ACT(BLK_TC_QUEUE))
	#define BLK_TA_FRONTMERGE (__BLK_TA_FRONTMERGE \| BLK_TC_ACT(BLK_TC_QUEUE))
	#define BLK_TA_GETRQ (__BLK_TA_GETRQ \| BLK_TC_ACT(BLK_TC_QUEUE))
	#define BLK_TA_SLEEPRQ (__BLK_TA_SLEEPRQ \| BLK_TC_ACT(BLK_TC_QUEUE))
	#define BLK_TA_REQUEUE (__BLK_TA_REQUEUE \| BLK_TC_ACT(BLK_TC_REQUEUE))
	#define BLK_TA_ISSUE (__BLK_TA_ISSUE \| BLK_TC_ACT(BLK_TC_ISSUE))
	#define BLK_TA_COMPLETE (__BLK_TA_COMPLETE\| BLK_TC_ACT(BLK_TC_COMPLETE))
	#define BLK_TA_PLUG (__BLK_TA_PLUG \| BLK_TC_ACT(BLK_TC_QUEUE))
	#define BLK_TA_UNPLUG_IO (__BLK_TA_UNPLUG_IO \| BLK_TC_ACT(BLK_TC_QUEUE))
	#define BLK_TA_UNPLUG_TIMER (__BLK_TA_UNPLUG_TIMER \| BLK_TC_ACT(BLK_TC_QUEUE))
	#define BLK_TA_INSERT (__BLK_TA_INSERT \| BLK_TC_ACT(BLK_TC_QUEUE))
	#define BLK_TA_SPLIT (__BLK_TA_SPLIT)
	#define BLK_TA_BOUNCE (__BLK_TA_BOUNCE)
	#define BLK_TA_REMAP (__BLK_TA_REMAP \| BLK_TC_ACT(BLK_TC_QUEUE))

	#define BLK_TN_PROCESS (__BLK_TN_PROCESS \| BLK_TC_ACT(BLK_TC_NOTIFY))
	#define BLK_TN_TIMESTAMP (__BLK_TN_TIMESTAMP \| BLK_TC_ACT(BLK_TC_NOTIFY))
	#define BLK_TN_MESSAGE (__BLK_TN_MESSAGE \| BLK_TC_ACT(BLK_TC_NOTIFY))

	#define BLK_IO_TRACE_MAGIC 0x65617400
	#define BLK_IO_TRACE_VERSION 0x07

	/*
	* The trace itself
	*/
	struct blk_io_trace {
	u32 magic; /* MAGIC << 8 \| version */
	u32 sequence; /* event number */
	u64 time; /* in microseconds */
	u64 sector; /* disk offset */
	u32 bytes; /* transfer length */
	u32 action; /* what happened */
	u32 pid; /* who did it */
	u32 device; /* device number */
	u32 cpu; /* on what cpu did it happen */
	u16 error; /* completion error */
	u16 pdu_len; /* length of data after this trace */
	};

	/*
	* The remap event
	*/
	struct blk_io_trace_remap {
	__be32 device;
	__be32 device_from;
	__be64 sector;
	};

	enum {
	Blktrace_setup = 1,
	Blktrace_running,
	Blktrace_stopped,
	};

	struct blk_trace {
	int trace_state;
	struct rchan *rchan;
	unsigned long *sequence;
	unsigned char *msg_data;
	u16 act_mask;
	u64 start_lba;
	u64 end_lba;
	u32 pid;
	u32 dev;
	struct dentry *dir;
	struct dentry *dropped_file;
	atomic_t dropped;
	};

	/*
	* User setup structure passed with BLKTRACESTART
	*/
	struct blk_user_trace_setup {
	char name[BDEVNAME_SIZE]; /* output */
	u16 act_mask; /* input */
	u32 buf_size; /* input */
	u32 buf_nr; /* input */
	u64 start_lba;
	u64 end_lba;
	u32 pid;
	};

	#ifdef __KERNEL__
	#if defined(CONFIG_BLK_DEV_IO_TRACE)
	extern int blk_trace_ioctl(struct block_device , unsigned, char __user );
	extern void blk_trace_shutdown(struct request_queue *);
	extern void __blk_add_trace(struct blk_trace , sector_t, int, int, u32, int, int, void );
	extern int do_blk_trace_setup(struct request_queue *q,
	char name, dev_t dev, struct blk_user_trace_setup buts);
	extern void __trace_note_message(struct blk_trace , const char fmt, ...);

	/**
	* blk_add_trace_msg - Add a (simple) message to the blktrace stream
	* @q: queue the io is for
	* @fmt: format to print message in
	* args... Variable argument list for format
	*
	* Description:
	* Records a (simple) message onto the blktrace stream.
	*
	* NOTE: BLK_TN_MAX_MSG characters are output at most.
	* NOTE: Can not use 'static inline' due to presence of var args...
	*
	**/
	#define blk_add_trace_msg(q, fmt, ...) \
	do { \
	struct blk_trace *bt = (q)->blk_trace; \
	if (unlikely(bt)) \
	__trace_note_message(bt, fmt, ##__VA_ARGS__); \
	} while (0)
	#define BLK_TN_MAX_MSG 128

	/**
	* blk_add_trace_rq - Add a trace for a request oriented action
	* @q: queue the io is for
	* @rq: the source request
	* @what: the action
	*
	* Description:
	* Records an action against a request. Will log the bio offset + size.
	*
	**/
	static inline void blk_add_trace_rq(struct request_queue q, struct request rq,
	u32 what)
	{
	struct blk_trace *bt = q->blk_trace;
	int rw = rq->cmd_flags & 0x03;

	if (likely(!bt))
	return;

	if (blk_pc_request(rq)) {
	what \|= BLK_TC_ACT(BLK_TC_PC);
	__blk_add_trace(bt, 0, rq->data_len, rw, what, rq->errors, sizeof(rq->cmd), rq->cmd);
	} else {
	what \|= BLK_TC_ACT(BLK_TC_FS);
	__blk_add_trace(bt, rq->hard_sector, rq->hard_nr_sectors << 9, rw, what, rq->errors, 0, NULL);
	}
	}

	/**
	* blk_add_trace_bio - Add a trace for a bio oriented action
	* @q: queue the io is for
	* @bio: the source bio
	* @what: the action
	*
	* Description:
	* Records an action against a bio. Will log the bio offset + size.
	*
	**/
	static inline void blk_add_trace_bio(struct request_queue q, struct bio bio,
	u32 what)
	{
	struct blk_trace *bt = q->blk_trace;

	if (likely(!bt))
	return;

	__blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, !bio_flagged(bio, BIO_UPTODATE), 0, NULL);
	}

	/**
	* blk_add_trace_generic - Add a trace for a generic action
	* @q: queue the io is for
	* @bio: the source bio
	* @rw: the data direction
	* @what: the action
	*
	* Description:
	* Records a simple trace
	*
	**/
	static inline void blk_add_trace_generic(struct request_queue *q,
	struct bio *bio, int rw, u32 what)
	{
	struct blk_trace *bt = q->blk_trace;

	if (likely(!bt))
	return;

	if (bio)
	blk_add_trace_bio(q, bio, what);
	else
	__blk_add_trace(bt, 0, 0, rw, what, 0, 0, NULL);
	}

	/**
	* blk_add_trace_pdu_int - Add a trace for a bio with an integer payload
	* @q: queue the io is for
	* @what: the action
	* @bio: the source bio
	* @pdu: the integer payload
	*
	* Description:
	* Adds a trace with some integer payload. This might be an unplug
	* option given as the action, with the depth at unplug time given
	* as the payload
	*
	**/
	static inline void blk_add_trace_pdu_int(struct request_queue *q, u32 what,
	struct bio *bio, unsigned int pdu)
	{
	struct blk_trace *bt = q->blk_trace;
	__be64 rpdu = cpu_to_be64(pdu);

	if (likely(!bt))
	return;

	if (bio)
	__blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, !bio_flagged(bio, BIO_UPTODATE), sizeof(rpdu), &rpdu);
	else
	__blk_add_trace(bt, 0, 0, 0, what, 0, sizeof(rpdu), &rpdu);
	}

	/**
	* blk_add_trace_remap - Add a trace for a remap operation
	* @q: queue the io is for
	* @bio: the source bio
	* @dev: target device
	* @from: source sector
	* @to: target sector
	*
	* Description:
	* Device mapper or raid target sometimes need to split a bio because
	* it spans a stripe (or similar). Add a trace for that action.
	*
	**/
	static inline void blk_add_trace_remap(struct request_queue q, struct bio bio,
	dev_t dev, sector_t from, sector_t to)
	{
	struct blk_trace *bt = q->blk_trace;
	struct blk_io_trace_remap r;

	if (likely(!bt))
	return;

	r.device = cpu_to_be32(dev);
	r.device_from = cpu_to_be32(bio->bi_bdev->bd_dev);
	r.sector = cpu_to_be64(to);

	__blk_add_trace(bt, from, bio->bi_size, bio->bi_rw, BLK_TA_REMAP, !bio_flagged(bio, BIO_UPTODATE), sizeof(r), &r);
	}

	extern int blk_trace_setup(struct request_queue q, char name, dev_t dev,
	char __user *arg);
	extern int blk_trace_startstop(struct request_queue *q, int start);
	extern int blk_trace_remove(struct request_queue *q);

	#else /* !CONFIG_BLK_DEV_IO_TRACE */
	#define blk_trace_ioctl(bdev, cmd, arg) (-ENOTTY)
	#define blk_trace_shutdown(q) do { } while (0)
	#define blk_add_trace_rq(q, rq, what) do { } while (0)
	#define blk_add_trace_bio(q, rq, what) do { } while (0)
	#define blk_add_trace_generic(q, rq, rw, what) do { } while (0)
	#define blk_add_trace_pdu_int(q, what, bio, pdu) do { } while (0)
	#define blk_add_trace_remap(q, bio, dev, f, t) do {} while (0)
	#define do_blk_trace_setup(q, name, dev, buts) (-ENOTTY)
	#define blk_trace_setup(q, name, dev, arg) (-ENOTTY)
	#define blk_trace_startstop(q, start) (-ENOTTY)
	#define blk_trace_remove(q) (-ENOTTY)
	#define blk_add_trace_msg(q, fmt, ...) do { } while (0)

	#endif /* CONFIG_BLK_DEV_IO_TRACE */
	#endif /* __KERNEL__ */
	#endif