Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
tjh.dev
kernel
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linux
1#ifndef BLKTRACE_H
2#define BLKTRACE_H
3
4#include <linux/blkdev.h>
5#include <linux/relay.h>
6
7/*
8 * Trace categories
9 */
10enum blktrace_cat {
11 BLK_TC_READ = 1 << 0, /* reads */
12 BLK_TC_WRITE = 1 << 1, /* writes */
13 BLK_TC_BARRIER = 1 << 2, /* barrier */
14 BLK_TC_SYNC = 1 << 3, /* sync IO */
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 */
22 BLK_TC_AHEAD = 1 << 11, /* readahead */
23 BLK_TC_META = 1 << 12, /* metadata */
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 */
34enum 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
52/*
53 * Notify events.
54 */
55enum blktrace_notify {
56 __BLK_TN_PROCESS = 0, /* establish pid/name mapping */
57 __BLK_TN_TIMESTAMP, /* include system clock */
58 __BLK_TN_MESSAGE, /* Character string message */
59};
60
61
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
81#define BLK_TN_PROCESS (__BLK_TN_PROCESS | BLK_TC_ACT(BLK_TC_NOTIFY))
82#define BLK_TN_TIMESTAMP (__BLK_TN_TIMESTAMP | BLK_TC_ACT(BLK_TC_NOTIFY))
83#define BLK_TN_MESSAGE (__BLK_TN_MESSAGE | BLK_TC_ACT(BLK_TC_NOTIFY))
84
85#define BLK_IO_TRACE_MAGIC 0x65617400
86#define BLK_IO_TRACE_VERSION 0x07
87
88/*
89 * The trace itself
90 */
91struct 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 */
108struct blk_io_trace_remap {
109 __be32 device;
110 __be32 device_from;
111 __be64 sector;
112};
113
114enum {
115 Blktrace_setup = 1,
116 Blktrace_running,
117 Blktrace_stopped,
118};
119
120struct blk_trace {
121 int trace_state;
122 struct rchan *rchan;
123 unsigned long *sequence;
124 unsigned char *msg_data;
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;
132 atomic_t dropped;
133};
134
135/*
136 * User setup structure passed with BLKTRACESTART
137 */
138struct blk_user_trace_setup {
139 char name[BDEVNAME_SIZE]; /* output */
140 u16 act_mask; /* input */
141 u32 buf_size; /* input */
142 u32 buf_nr; /* input */
143 u64 start_lba;
144 u64 end_lba;
145 u32 pid;
146};
147
148#ifdef __KERNEL__
149#if defined(CONFIG_BLK_DEV_IO_TRACE)
150extern int blk_trace_ioctl(struct block_device *, unsigned, char __user *);
151extern void blk_trace_shutdown(struct request_queue *);
152extern void __blk_add_trace(struct blk_trace *, sector_t, int, int, u32, int, int, void *);
153extern int do_blk_trace_setup(struct request_queue *q,
154 char *name, dev_t dev, struct blk_user_trace_setup *buts);
155extern void __trace_note_message(struct blk_trace *, const char *fmt, ...);
156
157/**
158 * blk_add_trace_msg - Add a (simple) message to the blktrace stream
159 * @q: queue the io is for
160 * @fmt: format to print message in
161 * args... Variable argument list for format
162 *
163 * Description:
164 * Records a (simple) message onto the blktrace stream.
165 *
166 * NOTE: BLK_TN_MAX_MSG characters are output at most.
167 * NOTE: Can not use 'static inline' due to presence of var args...
168 *
169 **/
170#define blk_add_trace_msg(q, fmt, ...) \
171 do { \
172 struct blk_trace *bt = (q)->blk_trace; \
173 if (unlikely(bt)) \
174 __trace_note_message(bt, fmt, ##__VA_ARGS__); \
175 } while (0)
176#define BLK_TN_MAX_MSG 128
177
178/**
179 * blk_add_trace_rq - Add a trace for a request oriented action
180 * @q: queue the io is for
181 * @rq: the source request
182 * @what: the action
183 *
184 * Description:
185 * Records an action against a request. Will log the bio offset + size.
186 *
187 **/
188static inline void blk_add_trace_rq(struct request_queue *q, struct request *rq,
189 u32 what)
190{
191 struct blk_trace *bt = q->blk_trace;
192 int rw = rq->cmd_flags & 0x03;
193
194 if (likely(!bt))
195 return;
196
197 if (blk_pc_request(rq)) {
198 what |= BLK_TC_ACT(BLK_TC_PC);
199 __blk_add_trace(bt, 0, rq->data_len, rw, what, rq->errors, sizeof(rq->cmd), rq->cmd);
200 } else {
201 what |= BLK_TC_ACT(BLK_TC_FS);
202 __blk_add_trace(bt, rq->hard_sector, rq->hard_nr_sectors << 9, rw, what, rq->errors, 0, NULL);
203 }
204}
205
206/**
207 * blk_add_trace_bio - Add a trace for a bio oriented action
208 * @q: queue the io is for
209 * @bio: the source bio
210 * @what: the action
211 *
212 * Description:
213 * Records an action against a bio. Will log the bio offset + size.
214 *
215 **/
216static inline void blk_add_trace_bio(struct request_queue *q, struct bio *bio,
217 u32 what)
218{
219 struct blk_trace *bt = q->blk_trace;
220
221 if (likely(!bt))
222 return;
223
224 __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, !bio_flagged(bio, BIO_UPTODATE), 0, NULL);
225}
226
227/**
228 * blk_add_trace_generic - Add a trace for a generic action
229 * @q: queue the io is for
230 * @bio: the source bio
231 * @rw: the data direction
232 * @what: the action
233 *
234 * Description:
235 * Records a simple trace
236 *
237 **/
238static inline void blk_add_trace_generic(struct request_queue *q,
239 struct bio *bio, int rw, u32 what)
240{
241 struct blk_trace *bt = q->blk_trace;
242
243 if (likely(!bt))
244 return;
245
246 if (bio)
247 blk_add_trace_bio(q, bio, what);
248 else
249 __blk_add_trace(bt, 0, 0, rw, what, 0, 0, NULL);
250}
251
252/**
253 * blk_add_trace_pdu_int - Add a trace for a bio with an integer payload
254 * @q: queue the io is for
255 * @what: the action
256 * @bio: the source bio
257 * @pdu: the integer payload
258 *
259 * Description:
260 * Adds a trace with some integer payload. This might be an unplug
261 * option given as the action, with the depth at unplug time given
262 * as the payload
263 *
264 **/
265static inline void blk_add_trace_pdu_int(struct request_queue *q, u32 what,
266 struct bio *bio, unsigned int pdu)
267{
268 struct blk_trace *bt = q->blk_trace;
269 __be64 rpdu = cpu_to_be64(pdu);
270
271 if (likely(!bt))
272 return;
273
274 if (bio)
275 __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, !bio_flagged(bio, BIO_UPTODATE), sizeof(rpdu), &rpdu);
276 else
277 __blk_add_trace(bt, 0, 0, 0, what, 0, sizeof(rpdu), &rpdu);
278}
279
280/**
281 * blk_add_trace_remap - Add a trace for a remap operation
282 * @q: queue the io is for
283 * @bio: the source bio
284 * @dev: target device
285 * @from: source sector
286 * @to: target sector
287 *
288 * Description:
289 * Device mapper or raid target sometimes need to split a bio because
290 * it spans a stripe (or similar). Add a trace for that action.
291 *
292 **/
293static inline void blk_add_trace_remap(struct request_queue *q, struct bio *bio,
294 dev_t dev, sector_t from, sector_t to)
295{
296 struct blk_trace *bt = q->blk_trace;
297 struct blk_io_trace_remap r;
298
299 if (likely(!bt))
300 return;
301
302 r.device = cpu_to_be32(dev);
303 r.device_from = cpu_to_be32(bio->bi_bdev->bd_dev);
304 r.sector = cpu_to_be64(to);
305
306 __blk_add_trace(bt, from, bio->bi_size, bio->bi_rw, BLK_TA_REMAP, !bio_flagged(bio, BIO_UPTODATE), sizeof(r), &r);
307}
308
309extern int blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
310 char __user *arg);
311extern int blk_trace_startstop(struct request_queue *q, int start);
312extern int blk_trace_remove(struct request_queue *q);
313
314#else /* !CONFIG_BLK_DEV_IO_TRACE */
315#define blk_trace_ioctl(bdev, cmd, arg) (-ENOTTY)
316#define blk_trace_shutdown(q) do { } while (0)
317#define blk_add_trace_rq(q, rq, what) do { } while (0)
318#define blk_add_trace_bio(q, rq, what) do { } while (0)
319#define blk_add_trace_generic(q, rq, rw, what) do { } while (0)
320#define blk_add_trace_pdu_int(q, what, bio, pdu) do { } while (0)
321#define blk_add_trace_remap(q, bio, dev, f, t) do {} while (0)
322#define do_blk_trace_setup(q, name, dev, buts) (-ENOTTY)
323#define blk_trace_setup(q, name, dev, arg) (-ENOTTY)
324#define blk_trace_startstop(q, start) (-ENOTTY)
325#define blk_trace_remove(q) (-ENOTTY)
326#define blk_add_trace_msg(q, fmt, ...) do { } while (0)
327
328#endif /* CONFIG_BLK_DEV_IO_TRACE */
329#endif /* __KERNEL__ */
330#endif