1 #ifndef BLKTRACE_H
2 #define BLKTRACE_H
3 
4 #include <linux/types.h>
5 #ifdef __KERNEL__
6 #include <linux/blkdev.h>
7 #include <linux/relay.h>
8 #include <linux/compat.h>
9 #endif
10 
11 /*
12  * Trace categories
13  */
14 enum blktrace_cat {
15 	BLK_TC_READ	= 1 << 0,	/* reads */
16 	BLK_TC_WRITE	= 1 << 1,	/* writes */
17 	BLK_TC_FLUSH	= 1 << 2,	/* flush */
18 	BLK_TC_SYNC	= 1 << 3,	/* sync IO */
19 	BLK_TC_SYNCIO	= BLK_TC_SYNC,
20 	BLK_TC_QUEUE	= 1 << 4,	/* queueing/merging */
21 	BLK_TC_REQUEUE	= 1 << 5,	/* requeueing */
22 	BLK_TC_ISSUE	= 1 << 6,	/* issue */
23 	BLK_TC_COMPLETE	= 1 << 7,	/* completions */
24 	BLK_TC_FS	= 1 << 8,	/* fs requests */
25 	BLK_TC_PC	= 1 << 9,	/* pc requests */
26 	BLK_TC_NOTIFY	= 1 << 10,	/* special message */
27 	BLK_TC_AHEAD	= 1 << 11,	/* readahead */
28 	BLK_TC_META	= 1 << 12,	/* metadata */
29 	BLK_TC_DISCARD	= 1 << 13,	/* discard requests */
30 	BLK_TC_DRV_DATA	= 1 << 14,	/* binary per-driver data */
31 	BLK_TC_FUA	= 1 << 15,	/* fua requests */
32 
33 	BLK_TC_END	= 1 << 15,	/* we've run out of bits! */
34 };
35 
36 #define BLK_TC_SHIFT		(16)
37 #define BLK_TC_ACT(act)		((act) << BLK_TC_SHIFT)
38 
39 /*
40  * Basic trace actions
41  */
42 enum blktrace_act {
43 	__BLK_TA_QUEUE = 1,		/* queued */
44 	__BLK_TA_BACKMERGE,		/* back merged to existing rq */
45 	__BLK_TA_FRONTMERGE,		/* front merge to existing rq */
46 	__BLK_TA_GETRQ,			/* allocated new request */
47 	__BLK_TA_SLEEPRQ,		/* sleeping on rq allocation */
48 	__BLK_TA_REQUEUE,		/* request requeued */
49 	__BLK_TA_ISSUE,			/* sent to driver */
50 	__BLK_TA_COMPLETE,		/* completed by driver */
51 	__BLK_TA_PLUG,			/* queue was plugged */
52 	__BLK_TA_UNPLUG_IO,		/* queue was unplugged by io */
53 	__BLK_TA_UNPLUG_TIMER,		/* queue was unplugged by timer */
54 	__BLK_TA_INSERT,		/* insert request */
55 	__BLK_TA_SPLIT,			/* bio was split */
56 	__BLK_TA_BOUNCE,		/* bio was bounced */
57 	__BLK_TA_REMAP,			/* bio was remapped */
58 	__BLK_TA_ABORT,			/* request aborted */
59 	__BLK_TA_DRV_DATA,		/* driver-specific binary data */
60 };
61 
62 /*
63  * Notify events.
64  */
65 enum blktrace_notify {
66 	__BLK_TN_PROCESS = 0,		/* establish pid/name mapping */
67 	__BLK_TN_TIMESTAMP,		/* include system clock */
68 	__BLK_TN_MESSAGE,		/* Character string message */
69 };
70 
71 
72 /*
73  * Trace actions in full. Additionally, read or write is masked
74  */
75 #define BLK_TA_QUEUE		(__BLK_TA_QUEUE | BLK_TC_ACT(BLK_TC_QUEUE))
76 #define BLK_TA_BACKMERGE	(__BLK_TA_BACKMERGE | BLK_TC_ACT(BLK_TC_QUEUE))
77 #define BLK_TA_FRONTMERGE	(__BLK_TA_FRONTMERGE | BLK_TC_ACT(BLK_TC_QUEUE))
78 #define	BLK_TA_GETRQ		(__BLK_TA_GETRQ | BLK_TC_ACT(BLK_TC_QUEUE))
79 #define	BLK_TA_SLEEPRQ		(__BLK_TA_SLEEPRQ | BLK_TC_ACT(BLK_TC_QUEUE))
80 #define	BLK_TA_REQUEUE		(__BLK_TA_REQUEUE | BLK_TC_ACT(BLK_TC_REQUEUE))
81 #define BLK_TA_ISSUE		(__BLK_TA_ISSUE | BLK_TC_ACT(BLK_TC_ISSUE))
82 #define BLK_TA_COMPLETE		(__BLK_TA_COMPLETE| BLK_TC_ACT(BLK_TC_COMPLETE))
83 #define BLK_TA_PLUG		(__BLK_TA_PLUG | BLK_TC_ACT(BLK_TC_QUEUE))
84 #define BLK_TA_UNPLUG_IO	(__BLK_TA_UNPLUG_IO | BLK_TC_ACT(BLK_TC_QUEUE))
85 #define BLK_TA_UNPLUG_TIMER	(__BLK_TA_UNPLUG_TIMER | BLK_TC_ACT(BLK_TC_QUEUE))
86 #define BLK_TA_INSERT		(__BLK_TA_INSERT | BLK_TC_ACT(BLK_TC_QUEUE))
87 #define BLK_TA_SPLIT		(__BLK_TA_SPLIT)
88 #define BLK_TA_BOUNCE		(__BLK_TA_BOUNCE)
89 #define BLK_TA_REMAP		(__BLK_TA_REMAP | BLK_TC_ACT(BLK_TC_QUEUE))
90 #define BLK_TA_ABORT		(__BLK_TA_ABORT | BLK_TC_ACT(BLK_TC_QUEUE))
91 #define BLK_TA_DRV_DATA	(__BLK_TA_DRV_DATA | BLK_TC_ACT(BLK_TC_DRV_DATA))
92 
93 #define BLK_TN_PROCESS		(__BLK_TN_PROCESS | BLK_TC_ACT(BLK_TC_NOTIFY))
94 #define BLK_TN_TIMESTAMP	(__BLK_TN_TIMESTAMP | BLK_TC_ACT(BLK_TC_NOTIFY))
95 #define BLK_TN_MESSAGE		(__BLK_TN_MESSAGE | BLK_TC_ACT(BLK_TC_NOTIFY))
96 
97 #define BLK_IO_TRACE_MAGIC	0x65617400
98 #define BLK_IO_TRACE_VERSION	0x07
99 
100 /*
101  * The trace itself
102  */
103 struct blk_io_trace {
104 	__u32 magic;		/* MAGIC << 8 | version */
105 	__u32 sequence;		/* event number */
106 	__u64 time;		/* in microseconds */
107 	__u64 sector;		/* disk offset */
108 	__u32 bytes;		/* transfer length */
109 	__u32 action;		/* what happened */
110 	__u32 pid;		/* who did it */
111 	__u32 device;		/* device number */
112 	__u32 cpu;		/* on what cpu did it happen */
113 	__u16 error;		/* completion error */
114 	__u16 pdu_len;		/* length of data after this trace */
115 };
116 
117 /*
118  * The remap event
119  */
120 struct blk_io_trace_remap {
121 	__be32 device_from;
122 	__be32 device_to;
123 	__be64 sector_from;
124 };
125 
126 enum {
127 	Blktrace_setup = 1,
128 	Blktrace_running,
129 	Blktrace_stopped,
130 };
131 
132 #define BLKTRACE_BDEV_SIZE	32
133 
134 /*
135  * User setup structure passed with BLKTRACESTART
136  */
137 struct blk_user_trace_setup {
138 	char name[BLKTRACE_BDEV_SIZE];	/* output */
139 	__u16 act_mask;			/* input */
140 	__u32 buf_size;			/* input */
141 	__u32 buf_nr;			/* input */
142 	__u64 start_lba;
143 	__u64 end_lba;
144 	__u32 pid;
145 };
146 
147 #ifdef __KERNEL__
148 #if defined(CONFIG_BLK_DEV_IO_TRACE)
149 
150 #include <linux/sysfs.h>
151 
152 struct blk_trace {
153 	int trace_state;
154 	struct rchan *rchan;
155 	unsigned long __percpu *sequence;
156 	unsigned char __percpu *msg_data;
157 	u16 act_mask;
158 	u64 start_lba;
159 	u64 end_lba;
160 	u32 pid;
161 	u32 dev;
162 	struct dentry *dir;
163 	struct dentry *dropped_file;
164 	struct dentry *msg_file;
165 	atomic_t dropped;
166 };
167 
168 extern int blk_trace_ioctl(struct block_device *, unsigned, char __user *);
169 extern void blk_trace_shutdown(struct request_queue *);
170 extern int do_blk_trace_setup(struct request_queue *q, char *name,
171 			      dev_t dev, struct block_device *bdev,
172 			      struct blk_user_trace_setup *buts);
173 extern __printf(2, 3)
174 void __trace_note_message(struct blk_trace *, const char *fmt, ...);
175 
176 /**
177  * blk_add_trace_msg - Add a (simple) message to the blktrace stream
178  * @q:		queue the io is for
179  * @fmt:	format to print message in
180  * args...	Variable argument list for format
181  *
182  * Description:
183  *     Records a (simple) message onto the blktrace stream.
184  *
185  *     NOTE: BLK_TN_MAX_MSG characters are output at most.
186  *     NOTE: Can not use 'static inline' due to presence of var args...
187  *
188  **/
189 #define blk_add_trace_msg(q, fmt, ...)					\
190 	do {								\
191 		struct blk_trace *bt = (q)->blk_trace;			\
192 		if (unlikely(bt))					\
193 			__trace_note_message(bt, fmt, ##__VA_ARGS__);	\
194 	} while (0)
195 #define BLK_TN_MAX_MSG		128
196 
197 extern void blk_add_driver_data(struct request_queue *q, struct request *rq,
198 				void *data, size_t len);
199 extern int blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
200 			   struct block_device *bdev,
201 			   char __user *arg);
202 extern int blk_trace_startstop(struct request_queue *q, int start);
203 extern int blk_trace_remove(struct request_queue *q);
204 extern void blk_trace_remove_sysfs(struct device *dev);
205 extern int blk_trace_init_sysfs(struct device *dev);
206 
207 extern struct attribute_group blk_trace_attr_group;
208 
209 #else /* !CONFIG_BLK_DEV_IO_TRACE */
210 # define blk_trace_ioctl(bdev, cmd, arg)		(-ENOTTY)
211 # define blk_trace_shutdown(q)				do { } while (0)
212 # define do_blk_trace_setup(q, name, dev, bdev, buts)	(-ENOTTY)
213 # define blk_add_driver_data(q, rq, data, len)		do {} while (0)
214 # define blk_trace_setup(q, name, dev, bdev, arg)	(-ENOTTY)
215 # define blk_trace_startstop(q, start)			(-ENOTTY)
216 # define blk_trace_remove(q)				(-ENOTTY)
217 # define blk_add_trace_msg(q, fmt, ...)			do { } while (0)
218 # define blk_trace_remove_sysfs(dev)			do { } while (0)
blk_trace_init_sysfs(struct device * dev)219 static inline int blk_trace_init_sysfs(struct device *dev)
220 {
221 	return 0;
222 }
223 
224 #endif /* CONFIG_BLK_DEV_IO_TRACE */
225 
226 #ifdef CONFIG_COMPAT
227 
228 struct compat_blk_user_trace_setup {
229 	char name[32];
230 	u16 act_mask;
231 	u32 buf_size;
232 	u32 buf_nr;
233 	compat_u64 start_lba;
234 	compat_u64 end_lba;
235 	u32 pid;
236 };
237 #define BLKTRACESETUP32 _IOWR(0x12, 115, struct compat_blk_user_trace_setup)
238 
239 #endif
240 
241 #if defined(CONFIG_EVENT_TRACING) && defined(CONFIG_BLOCK)
242 
blk_cmd_buf_len(struct request * rq)243 static inline int blk_cmd_buf_len(struct request *rq)
244 {
245 	return (rq->cmd_type == REQ_TYPE_BLOCK_PC) ? rq->cmd_len * 3 : 1;
246 }
247 
248 extern void blk_dump_cmd(char *buf, struct request *rq);
249 extern void blk_fill_rwbs(char *rwbs, u32 rw, int bytes);
250 
251 #endif /* CONFIG_EVENT_TRACING && CONFIG_BLOCK */
252 
253 #endif /* __KERNEL__ */
254 #endif
255