aboutsummaryrefslogtreecommitdiffstats
path: root/include/linux/blktrace_api.h
blob: d960889e92efa17a73ee8038603a622be8dcf8a0 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
#ifndef BLKTRACE_H
#define BLKTRACE_H

#include <linux/types.h>
#ifdef __KERNEL__
#include <linux/blkdev.h>
#include <linux/relay.h>
#endif

/*
 * 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_SYNCIO	= BLK_TC_SYNC,
	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_DISCARD	= 1 << 13,	/* discard requests */
	BLK_TC_DRV_DATA	= 1 << 14,	/* binary per-driver data */

	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 */
	__BLK_TA_ABORT,			/* request aborted */
	__BLK_TA_DRV_DATA,		/* driver-specific binary data */
};

/*
 * 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_TA_ABORT		(__BLK_TA_ABORT | BLK_TC_ACT(BLK_TC_QUEUE))
#define BLK_TA_DRV_DATA	(__BLK_TA_DRV_DATA | BLK_TC_ACT(BLK_TC_DRV_DATA))

#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,
};

#define BLKTRACE_BDEV_SIZE	32

/*
 * User setup structure passed with BLKTRACESTART
 */
struct blk_user_trace_setup {
	char name[BLKTRACE_BDEV_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)

#include <linux/sysfs.h>

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;
};

extern int blk_trace_ioctl(struct block_device *, unsigned, char __user *);
extern void blk_trace_shutdown(struct request_queue *);
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

extern void blk_add_driver_data(struct request_queue *q, struct request *rq,
				void *data, size_t len);
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);

extern struct attribute_group blk_trace_attr_group;

#else /* !CONFIG_BLK_DEV_IO_TRACE */
#define blk_trace_ioctl(bdev, cmd, arg)		(-ENOTTY)
#define blk_trace_shutdown(q)			do { } while (0)
#define do_blk_trace_setup(q, name, dev, buts)	(-ENOTTY)
#define blk_add_driver_data(q, rq, data, len)	do {} while (0)
#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