[net-next-2.6.git] / include / linux / blktrace_api.h

#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;
	struct dentry *msg_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
Commit	Line	Data
2056a782 JA	1	#ifndef BLKTRACE_H
	2	#define BLKTRACE_H
	3
2056a782 JA	4	#include <linux/blkdev.h>
	5	#include <linux/relay.h>
	6
	7	/*
	8	* Trace categories
	9	*/
	10	enum blktrace_cat {
	11	BLK_TC_READ = 1 << 0, /* reads */
	12	BLK_TC_WRITE = 1 << 1, /* writes */
	13	BLK_TC_BARRIER = 1 << 2, /* barrier */
fc0a75ce	14	BLK_TC_SYNC = 1 << 3, /* sync IO */
2056a782 JA	15	BLK_TC_QUEUE = 1 << 4, /* queueing/merging */
	16	BLK_TC_REQUEUE = 1 << 5, /* requeueing */
	17	BLK_TC_ISSUE = 1 << 6, /* issue */
	18	BLK_TC_COMPLETE = 1 << 7, /* completions */
	19	BLK_TC_FS = 1 << 8, /* fs requests */
	20	BLK_TC_PC = 1 << 9, /* pc requests */
	21	BLK_TC_NOTIFY = 1 << 10, /* special message */
40359ccb	22	BLK_TC_AHEAD = 1 << 11, /* readahead */
7457e6e2	23	BLK_TC_META = 1 << 12, /* metadata */
2056a782 JA	24
	25	BLK_TC_END = 1 << 15, /* only 16-bits, reminder */
	26	};
	27
	28	#define BLK_TC_SHIFT (16)
	29	#define BLK_TC_ACT(act) ((act) << BLK_TC_SHIFT)
	30
	31	/*
	32	* Basic trace actions
	33	*/
	34	enum blktrace_act {
	35	__BLK_TA_QUEUE = 1, /* queued */
	36	__BLK_TA_BACKMERGE, /* back merged to existing rq */
	37	__BLK_TA_FRONTMERGE, /* front merge to existing rq */
	38	__BLK_TA_GETRQ, /* allocated new request */
	39	__BLK_TA_SLEEPRQ, /* sleeping on rq allocation */
	40	__BLK_TA_REQUEUE, /* request requeued */
	41	__BLK_TA_ISSUE, /* sent to driver */
	42	__BLK_TA_COMPLETE, /* completed by driver */
	43	__BLK_TA_PLUG, /* queue was plugged */
	44	__BLK_TA_UNPLUG_IO, /* queue was unplugged by io */
	45	__BLK_TA_UNPLUG_TIMER, /* queue was unplugged by timer */
	46	__BLK_TA_INSERT, /* insert request */
	47	__BLK_TA_SPLIT, /* bio was split */
	48	__BLK_TA_BOUNCE, /* bio was bounced */
	49	__BLK_TA_REMAP, /* bio was remapped */
	50	};
	51
be1c6341 OK	52	/*
	53	* Notify events.
	54	*/
	55	enum blktrace_notify {
	56	__BLK_TN_PROCESS = 0, /* establish pid/name mapping */
	57	__BLK_TN_TIMESTAMP, /* include system clock */
9d5f09a4	58	__BLK_TN_MESSAGE, /* Character string message */
be1c6341 OK	59	};
	60
	61
2056a782 JA	62	/*
	63	* Trace actions in full. Additionally, read or write is masked
	64	*/
	65	#define BLK_TA_QUEUE (__BLK_TA_QUEUE \| BLK_TC_ACT(BLK_TC_QUEUE))
	66	#define BLK_TA_BACKMERGE (__BLK_TA_BACKMERGE \| BLK_TC_ACT(BLK_TC_QUEUE))
	67	#define BLK_TA_FRONTMERGE (__BLK_TA_FRONTMERGE \| BLK_TC_ACT(BLK_TC_QUEUE))
	68	#define BLK_TA_GETRQ (__BLK_TA_GETRQ \| BLK_TC_ACT(BLK_TC_QUEUE))
	69	#define BLK_TA_SLEEPRQ (__BLK_TA_SLEEPRQ \| BLK_TC_ACT(BLK_TC_QUEUE))
	70	#define BLK_TA_REQUEUE (__BLK_TA_REQUEUE \| BLK_TC_ACT(BLK_TC_REQUEUE))
	71	#define BLK_TA_ISSUE (__BLK_TA_ISSUE \| BLK_TC_ACT(BLK_TC_ISSUE))
	72	#define BLK_TA_COMPLETE (__BLK_TA_COMPLETE\| BLK_TC_ACT(BLK_TC_COMPLETE))
	73	#define BLK_TA_PLUG (__BLK_TA_PLUG \| BLK_TC_ACT(BLK_TC_QUEUE))
	74	#define BLK_TA_UNPLUG_IO (__BLK_TA_UNPLUG_IO \| BLK_TC_ACT(BLK_TC_QUEUE))
	75	#define BLK_TA_UNPLUG_TIMER (__BLK_TA_UNPLUG_TIMER \| BLK_TC_ACT(BLK_TC_QUEUE))
	76	#define BLK_TA_INSERT (__BLK_TA_INSERT \| BLK_TC_ACT(BLK_TC_QUEUE))
	77	#define BLK_TA_SPLIT (__BLK_TA_SPLIT)
	78	#define BLK_TA_BOUNCE (__BLK_TA_BOUNCE)
	79	#define BLK_TA_REMAP (__BLK_TA_REMAP \| BLK_TC_ACT(BLK_TC_QUEUE))
	80
be1c6341 OK	81	#define BLK_TN_PROCESS (__BLK_TN_PROCESS \| BLK_TC_ACT(BLK_TC_NOTIFY))
be1c6341 OK	82	#define BLK_TN_TIMESTAMP (__BLK_TN_TIMESTAMP \| BLK_TC_ACT(BLK_TC_NOTIFY))
9d5f09a4	83	#define BLK_TN_MESSAGE (__BLK_TN_MESSAGE \| BLK_TC_ACT(BLK_TC_NOTIFY))
be1c6341	84
2056a782 JA	85	#define BLK_IO_TRACE_MAGIC 0x65617400
	86	#define BLK_IO_TRACE_VERSION 0x07
	87
	88	/*
	89	* The trace itself
	90	*/
	91	struct blk_io_trace {
	92	u32 magic; /* MAGIC << 8 \| version */
	93	u32 sequence; /* event number */
	94	u64 time; /* in microseconds */
	95	u64 sector; /* disk offset */
	96	u32 bytes; /* transfer length */
	97	u32 action; /* what happened */
	98	u32 pid; /* who did it */
	99	u32 device; /* device number */
	100	u32 cpu; /* on what cpu did it happen */
	101	u16 error; /* completion error */
	102	u16 pdu_len; /* length of data after this trace */
	103	};
	104
	105	/*
	106	* The remap event
	107	*/
	108	struct blk_io_trace_remap {
fda151d9	109	__be32 device;
c7149d6b	110	__be32 device_from;
fda151d9	111	__be64 sector;
2056a782 JA	112	};
	113
	114	enum {
	115	Blktrace_setup = 1,
	116	Blktrace_running,
	117	Blktrace_stopped,
	118	};
	119
	120	struct blk_trace {
	121	int trace_state;
	122	struct rchan *rchan;
	123	unsigned long *sequence;
64565911	124	unsigned char *msg_data;
2056a782 JA	125	u16 act_mask;
	126	u64 start_lba;
	127	u64 end_lba;
	128	u32 pid;
	129	u32 dev;
	130	struct dentry *dir;
	131	struct dentry *dropped_file;
02c62304	132	struct dentry *msg_file;
2056a782 JA	133	atomic_t dropped;
	134	};
	135
	136	/*
	137	* User setup structure passed with BLKTRACESTART
	138	*/
	139	struct blk_user_trace_setup {
	140	char name[BDEVNAME_SIZE]; /* output */
	141	u16 act_mask; /* input */
	142	u32 buf_size; /* input */
	143	u32 buf_nr; /* input */
	144	u64 start_lba;
	145	u64 end_lba;
	146	u32 pid;
	147	};
	148
171044d4	149	#ifdef __KERNEL__
2056a782 JA	150	#if defined(CONFIG_BLK_DEV_IO_TRACE)
2056a782 JA	151	extern int blk_trace_ioctl(struct block_device , unsigned, char __user );
165125e1	152	extern void blk_trace_shutdown(struct request_queue *);
2056a782	153	extern void __blk_add_trace(struct blk_trace , sector_t, int, int, u32, int, int, void );
171044d4	154	extern int do_blk_trace_setup(struct request_queue *q,
6da127ad	155	char name, dev_t dev, struct blk_user_trace_setup buts);
9d5f09a4	156	extern void __trace_note_message(struct blk_trace , const char fmt, ...);
171044d4	157
9d5f09a4 AB	158	/**
	159	* blk_add_trace_msg - Add a (simple) message to the blktrace stream
	160	* @q: queue the io is for
	161	* @fmt: format to print message in
	162	* args... Variable argument list for format
	163	*
	164	* Description:
	165	* Records a (simple) message onto the blktrace stream.
	166	*
	167	* NOTE: BLK_TN_MAX_MSG characters are output at most.
	168	* NOTE: Can not use 'static inline' due to presence of var args...
	169	*
	170	**/
	171	#define blk_add_trace_msg(q, fmt, ...) \
	172	do { \
	173	struct blk_trace *bt = (q)->blk_trace; \
	174	if (unlikely(bt)) \
	175	__trace_note_message(bt, fmt, ##__VA_ARGS__); \
	176	} while (0)
64565911	177	#define BLK_TN_MAX_MSG 128
2056a782 JA	178
	179	/**
	180	* blk_add_trace_rq - Add a trace for a request oriented action
	181	* @q: queue the io is for
	182	* @rq: the source request
	183	* @what: the action
	184	*
	185	* Description:
	186	* Records an action against a request. Will log the bio offset + size.
	187	*
	188	**/
	189	static inline void blk_add_trace_rq(struct request_queue q, struct request rq,
	190	u32 what)
	191	{
	192	struct blk_trace *bt = q->blk_trace;
4aff5e23	193	int rw = rq->cmd_flags & 0x03;
2056a782 JA	194
	195	if (likely(!bt))
	196	return;
	197
	198	if (blk_pc_request(rq)) {
	199	what \|= BLK_TC_ACT(BLK_TC_PC);
	200	__blk_add_trace(bt, 0, rq->data_len, rw, what, rq->errors, sizeof(rq->cmd), rq->cmd);
	201	} else {
	202	what \|= BLK_TC_ACT(BLK_TC_FS);
	203	__blk_add_trace(bt, rq->hard_sector, rq->hard_nr_sectors << 9, rw, what, rq->errors, 0, NULL);
	204	}
	205	}
	206
	207	/**
	208	* blk_add_trace_bio - Add a trace for a bio oriented action
	209	* @q: queue the io is for
	210	* @bio: the source bio
	211	* @what: the action
	212	*
	213	* Description:
	214	* Records an action against a bio. Will log the bio offset + size.
	215	*
	216	**/
	217	static inline void blk_add_trace_bio(struct request_queue q, struct bio bio,
	218	u32 what)
	219	{
	220	struct blk_trace *bt = q->blk_trace;
	221
	222	if (likely(!bt))
	223	return;
	224
	225	__blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, !bio_flagged(bio, BIO_UPTODATE), 0, NULL);
	226	}
	227
	228	/**
	229	* blk_add_trace_generic - Add a trace for a generic action
	230	* @q: queue the io is for
	231	* @bio: the source bio
	232	* @rw: the data direction
	233	* @what: the action
	234	*
	235	* Description:
	236	* Records a simple trace
	237	*
	238	**/
	239	static inline void blk_add_trace_generic(struct request_queue *q,
	240	struct bio *bio, int rw, u32 what)
	241	{
	242	struct blk_trace *bt = q->blk_trace;
	243
	244	if (likely(!bt))
	245	return;
	246
	247	if (bio)
	248	blk_add_trace_bio(q, bio, what);
	249	else
	250	__blk_add_trace(bt, 0, 0, rw, what, 0, 0, NULL);
	251	}
	252
	253	/**
	254	* blk_add_trace_pdu_int - Add a trace for a bio with an integer payload
	255	* @q: queue the io is for
	256	* @what: the action
	257	* @bio: the source bio
258	* @pdu: the integer payload
259	*
260	* Description:
261	* Adds a trace with some integer payload. This might be an unplug
262	* option given as the action, with the depth at unplug time given
263	* as the payload
264	*
265	**/
266	static inline void blk_add_trace_pdu_int(struct request_queue *q, u32 what,
267	struct bio *bio, unsigned int pdu)
268	{
269	struct blk_trace *bt = q->blk_trace;
fda151d9	270	__be64 rpdu = cpu_to_be64(pdu);
2056a782 JA	271
	272	if (likely(!bt))
	273	return;
	274
	275	if (bio)
	276	__blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, !bio_flagged(bio, BIO_UPTODATE), sizeof(rpdu), &rpdu);
	277	else
	278	__blk_add_trace(bt, 0, 0, 0, what, 0, sizeof(rpdu), &rpdu);
	279	}
	280
	281	/**
	282	* blk_add_trace_remap - Add a trace for a remap operation
	283	* @q: queue the io is for
	284	* @bio: the source bio
	285	* @dev: target device
	286	* @from: source sector
	287	* @to: target sector
	288	*
	289	* Description:
	290	* Device mapper or raid target sometimes need to split a bio because
	291	* it spans a stripe (or similar). Add a trace for that action.
	292	*
	293	**/
	294	static inline void blk_add_trace_remap(struct request_queue q, struct bio bio,
	295	dev_t dev, sector_t from, sector_t to)
	296	{
	297	struct blk_trace *bt = q->blk_trace;
	298	struct blk_io_trace_remap r;
	299
	300	if (likely(!bt))
	301	return;
	302
	303	r.device = cpu_to_be32(dev);
c7149d6b	304	r.device_from = cpu_to_be32(bio->bi_bdev->bd_dev);
2056a782 JA	305	r.sector = cpu_to_be64(to);
	306
	307	__blk_add_trace(bt, from, bio->bi_size, bio->bi_rw, BLK_TA_REMAP, !bio_flagged(bio, BIO_UPTODATE), sizeof(r), &r);
	308	}
	309
7da975a2	310	extern int blk_trace_setup(struct request_queue q, char name, dev_t dev,
6da127ad	311	char __user *arg);
7da975a2 MP	312	extern int blk_trace_startstop(struct request_queue *q, int start);
7da975a2 MP	313	extern int blk_trace_remove(struct request_queue *q);
6da127ad	314
2056a782 JA	315	#else /* !CONFIG_BLK_DEV_IO_TRACE */
	316	#define blk_trace_ioctl(bdev, cmd, arg) (-ENOTTY)
	317	#define blk_trace_shutdown(q) do { } while (0)
	318	#define blk_add_trace_rq(q, rq, what) do { } while (0)
	319	#define blk_add_trace_bio(q, rq, what) do { } while (0)
	320	#define blk_add_trace_generic(q, rq, rw, what) do { } while (0)
	321	#define blk_add_trace_pdu_int(q, what, bio, pdu) do { } while (0)
	322	#define blk_add_trace_remap(q, bio, dev, f, t) do {} while (0)
6da127ad CS	323	#define do_blk_trace_setup(q, name, dev, buts) (-ENOTTY)
	324	#define blk_trace_setup(q, name, dev, arg) (-ENOTTY)
	325	#define blk_trace_startstop(q, start) (-ENOTTY)
	326	#define blk_trace_remove(q) (-ENOTTY)
9d5f09a4 AB	327	#define blk_add_trace_msg(q, fmt, ...) do { } while (0)
9d5f09a4 AB	328
2056a782	329	#endif /* CONFIG_BLK_DEV_IO_TRACE */
171044d4	330	#endif /* __KERNEL__ */
2056a782	331	#endif