1 #ifndef BLKTRACE_H 2 #define BLKTRACE_H 3 4 #ifdef __KERNEL__ 5 #include <linux/blkdev.h> 6 #include <linux/relay.h> 7 #endif 8 9 /* 10 * Trace categories 11 */ 12 enum blktrace_cat { 13 BLK_TC_READ = 1 << 0, /* reads */ 14 BLK_TC_WRITE = 1 << 1, /* writes */ 15 BLK_TC_BARRIER = 1 << 2, /* barrier */ 16 BLK_TC_SYNC = 1 << 3, /* sync IO */ 17 BLK_TC_QUEUE = 1 << 4, /* queueing/merging */ 18 BLK_TC_REQUEUE = 1 << 5, /* requeueing */ 19 BLK_TC_ISSUE = 1 << 6, /* issue */ 20 BLK_TC_COMPLETE = 1 << 7, /* completions */ 21 BLK_TC_FS = 1 << 8, /* fs requests */ 22 BLK_TC_PC = 1 << 9, /* pc requests */ 23 BLK_TC_NOTIFY = 1 << 10, /* special message */ 24 BLK_TC_AHEAD = 1 << 11, /* readahead */ 25 BLK_TC_META = 1 << 12, /* metadata */ 26 BLK_TC_DISCARD = 1 << 13, /* discard requests */ 27 BLK_TC_DRV_DATA = 1 << 14, /* binary per-driver data */ 28 29 BLK_TC_END = 1 << 15, /* only 16-bits, reminder */ 30 }; 31 32 #define BLK_TC_SHIFT (16) 33 #define BLK_TC_ACT(act) ((act) << BLK_TC_SHIFT) 34 35 /* 36 * Basic trace actions 37 */ 38 enum blktrace_act { 39 __BLK_TA_QUEUE = 1, /* queued */ 40 __BLK_TA_BACKMERGE, /* back merged to existing rq */ 41 __BLK_TA_FRONTMERGE, /* front merge to existing rq */ 42 __BLK_TA_GETRQ, /* allocated new request */ 43 __BLK_TA_SLEEPRQ, /* sleeping on rq allocation */ 44 __BLK_TA_REQUEUE, /* request requeued */ 45 __BLK_TA_ISSUE, /* sent to driver */ 46 __BLK_TA_COMPLETE, /* completed by driver */ 47 __BLK_TA_PLUG, /* queue was plugged */ 48 __BLK_TA_UNPLUG_IO, /* queue was unplugged by io */ 49 __BLK_TA_UNPLUG_TIMER, /* queue was unplugged by timer */ 50 __BLK_TA_INSERT, /* insert request */ 51 __BLK_TA_SPLIT, /* bio was split */ 52 __BLK_TA_BOUNCE, /* bio was bounced */ 53 __BLK_TA_REMAP, /* bio was remapped */ 54 __BLK_TA_ABORT, /* request aborted */ 55 __BLK_TA_DRV_DATA, /* driver-specific binary data */ 56 }; 57 58 /* 59 * Notify events. 60 */ 61 enum blktrace_notify { 62 __BLK_TN_PROCESS = 0, /* establish pid/name mapping */ 63 __BLK_TN_TIMESTAMP, /* include system clock */ 64 __BLK_TN_MESSAGE, /* Character string message */ 65 }; 66 67 68 /* 69 * Trace actions in full. Additionally, read or write is masked 70 */ 71 #define BLK_TA_QUEUE (__BLK_TA_QUEUE | BLK_TC_ACT(BLK_TC_QUEUE)) 72 #define BLK_TA_BACKMERGE (__BLK_TA_BACKMERGE | BLK_TC_ACT(BLK_TC_QUEUE)) 73 #define BLK_TA_FRONTMERGE (__BLK_TA_FRONTMERGE | BLK_TC_ACT(BLK_TC_QUEUE)) 74 #define BLK_TA_GETRQ (__BLK_TA_GETRQ | BLK_TC_ACT(BLK_TC_QUEUE)) 75 #define BLK_TA_SLEEPRQ (__BLK_TA_SLEEPRQ | BLK_TC_ACT(BLK_TC_QUEUE)) 76 #define BLK_TA_REQUEUE (__BLK_TA_REQUEUE | BLK_TC_ACT(BLK_TC_REQUEUE)) 77 #define BLK_TA_ISSUE (__BLK_TA_ISSUE | BLK_TC_ACT(BLK_TC_ISSUE)) 78 #define BLK_TA_COMPLETE (__BLK_TA_COMPLETE| BLK_TC_ACT(BLK_TC_COMPLETE)) 79 #define BLK_TA_PLUG (__BLK_TA_PLUG | BLK_TC_ACT(BLK_TC_QUEUE)) 80 #define BLK_TA_UNPLUG_IO (__BLK_TA_UNPLUG_IO | BLK_TC_ACT(BLK_TC_QUEUE)) 81 #define BLK_TA_UNPLUG_TIMER (__BLK_TA_UNPLUG_TIMER | BLK_TC_ACT(BLK_TC_QUEUE)) 82 #define BLK_TA_INSERT (__BLK_TA_INSERT | BLK_TC_ACT(BLK_TC_QUEUE)) 83 #define BLK_TA_SPLIT (__BLK_TA_SPLIT) 84 #define BLK_TA_BOUNCE (__BLK_TA_BOUNCE) 85 #define BLK_TA_REMAP (__BLK_TA_REMAP | BLK_TC_ACT(BLK_TC_QUEUE)) 86 #define BLK_TA_ABORT (__BLK_TA_ABORT | BLK_TC_ACT(BLK_TC_QUEUE)) 87 #define BLK_TA_DRV_DATA (__BLK_TA_DRV_DATA | BLK_TC_ACT(BLK_TC_DRV_DATA)) 88 89 #define BLK_TN_PROCESS (__BLK_TN_PROCESS | BLK_TC_ACT(BLK_TC_NOTIFY)) 90 #define BLK_TN_TIMESTAMP (__BLK_TN_TIMESTAMP | BLK_TC_ACT(BLK_TC_NOTIFY)) 91 #define BLK_TN_MESSAGE (__BLK_TN_MESSAGE | BLK_TC_ACT(BLK_TC_NOTIFY)) 92 93 #define BLK_IO_TRACE_MAGIC 0x65617400 94 #define BLK_IO_TRACE_VERSION 0x07 95 96 /* 97 * The trace itself 98 */ 99 struct blk_io_trace { 100 __u32 magic; /* MAGIC << 8 | version */ 101 __u32 sequence; /* event number */ 102 __u64 time; /* in microseconds */ 103 __u64 sector; /* disk offset */ 104 __u32 bytes; /* transfer length */ 105 __u32 action; /* what happened */ 106 __u32 pid; /* who did it */ 107 __u32 device; /* device number */ 108 __u32 cpu; /* on what cpu did it happen */ 109 __u16 error; /* completion error */ 110 __u16 pdu_len; /* length of data after this trace */ 111 }; 112 113 /* 114 * The remap event 115 */ 116 struct blk_io_trace_remap { 117 __be32 device; 118 __be32 device_from; 119 __be64 sector; 120 }; 121 122 enum { 123 Blktrace_setup = 1, 124 Blktrace_running, 125 Blktrace_stopped, 126 }; 127 128 #define BLKTRACE_BDEV_SIZE 32 129 130 /* 131 * User setup structure passed with BLKTRACESTART 132 */ 133 struct blk_user_trace_setup { 134 char name[BLKTRACE_BDEV_SIZE]; /* output */ 135 __u16 act_mask; /* input */ 136 __u32 buf_size; /* input */ 137 __u32 buf_nr; /* input */ 138 __u64 start_lba; 139 __u64 end_lba; 140 __u32 pid; 141 }; 142 143 #ifdef __KERNEL__ 144 #if defined(CONFIG_BLK_DEV_IO_TRACE) 145 struct blk_trace { 146 int trace_state; 147 struct rchan *rchan; 148 unsigned long *sequence; 149 unsigned char *msg_data; 150 u16 act_mask; 151 u64 start_lba; 152 u64 end_lba; 153 u32 pid; 154 u32 dev; 155 struct dentry *dir; 156 struct dentry *dropped_file; 157 struct dentry *msg_file; 158 atomic_t dropped; 159 }; 160 161 extern int blk_trace_ioctl(struct block_device *, unsigned, char __user *); 162 extern void blk_trace_shutdown(struct request_queue *); 163 extern void __blk_add_trace(struct blk_trace *, sector_t, int, int, u32, int, int, void *); 164 extern int do_blk_trace_setup(struct request_queue *q, 165 char *name, dev_t dev, struct blk_user_trace_setup *buts); 166 extern void __trace_note_message(struct blk_trace *, const char *fmt, ...); 167 168 /** 169 * blk_add_trace_msg - Add a (simple) message to the blktrace stream 170 * @q: queue the io is for 171 * @fmt: format to print message in 172 * args... Variable argument list for format 173 * 174 * Description: 175 * Records a (simple) message onto the blktrace stream. 176 * 177 * NOTE: BLK_TN_MAX_MSG characters are output at most. 178 * NOTE: Can not use 'static inline' due to presence of var args... 179 * 180 **/ 181 #define blk_add_trace_msg(q, fmt, ...) \ 182 do { \ 183 struct blk_trace *bt = (q)->blk_trace; \ 184 if (unlikely(bt)) \ 185 __trace_note_message(bt, fmt, ##__VA_ARGS__); \ 186 } while (0) 187 #define BLK_TN_MAX_MSG 128 188 189 /** 190 * blk_add_trace_rq - Add a trace for a request oriented action 191 * @q: queue the io is for 192 * @rq: the source request 193 * @what: the action 194 * 195 * Description: 196 * Records an action against a request. Will log the bio offset + size. 197 * 198 **/ 199 static inline void blk_add_trace_rq(struct request_queue *q, struct request *rq, 200 u32 what) 201 { 202 struct blk_trace *bt = q->blk_trace; 203 int rw = rq->cmd_flags & 0x03; 204 205 if (likely(!bt)) 206 return; 207 208 if (blk_discard_rq(rq)) 209 rw |= (1 << BIO_RW_DISCARD); 210 211 if (blk_pc_request(rq)) { 212 what |= BLK_TC_ACT(BLK_TC_PC); 213 __blk_add_trace(bt, 0, rq->data_len, rw, what, rq->errors, sizeof(rq->cmd), rq->cmd); 214 } else { 215 what |= BLK_TC_ACT(BLK_TC_FS); 216 __blk_add_trace(bt, rq->hard_sector, rq->hard_nr_sectors << 9, rw, what, rq->errors, 0, NULL); 217 } 218 } 219 220 /** 221 * blk_add_trace_bio - Add a trace for a bio oriented action 222 * @q: queue the io is for 223 * @bio: the source bio 224 * @what: the action 225 * 226 * Description: 227 * Records an action against a bio. Will log the bio offset + size. 228 * 229 **/ 230 static inline void blk_add_trace_bio(struct request_queue *q, struct bio *bio, 231 u32 what) 232 { 233 struct blk_trace *bt = q->blk_trace; 234 235 if (likely(!bt)) 236 return; 237 238 __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, !bio_flagged(bio, BIO_UPTODATE), 0, NULL); 239 } 240 241 /** 242 * blk_add_trace_generic - Add a trace for a generic action 243 * @q: queue the io is for 244 * @bio: the source bio 245 * @rw: the data direction 246 * @what: the action 247 * 248 * Description: 249 * Records a simple trace 250 * 251 **/ 252 static inline void blk_add_trace_generic(struct request_queue *q, 253 struct bio *bio, int rw, u32 what) 254 { 255 struct blk_trace *bt = q->blk_trace; 256 257 if (likely(!bt)) 258 return; 259 260 if (bio) 261 blk_add_trace_bio(q, bio, what); 262 else 263 __blk_add_trace(bt, 0, 0, rw, what, 0, 0, NULL); 264 } 265 266 /** 267 * blk_add_trace_pdu_int - Add a trace for a bio with an integer payload 268 * @q: queue the io is for 269 * @what: the action 270 * @bio: the source bio 271 * @pdu: the integer payload 272 * 273 * Description: 274 * Adds a trace with some integer payload. This might be an unplug 275 * option given as the action, with the depth at unplug time given 276 * as the payload 277 * 278 **/ 279 static inline void blk_add_trace_pdu_int(struct request_queue *q, u32 what, 280 struct bio *bio, unsigned int pdu) 281 { 282 struct blk_trace *bt = q->blk_trace; 283 __be64 rpdu = cpu_to_be64(pdu); 284 285 if (likely(!bt)) 286 return; 287 288 if (bio) 289 __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, !bio_flagged(bio, BIO_UPTODATE), sizeof(rpdu), &rpdu); 290 else 291 __blk_add_trace(bt, 0, 0, 0, what, 0, sizeof(rpdu), &rpdu); 292 } 293 294 /** 295 * blk_add_trace_remap - Add a trace for a remap operation 296 * @q: queue the io is for 297 * @bio: the source bio 298 * @dev: target device 299 * @from: source sector 300 * @to: target sector 301 * 302 * Description: 303 * Device mapper or raid target sometimes need to split a bio because 304 * it spans a stripe (or similar). Add a trace for that action. 305 * 306 **/ 307 static inline void blk_add_trace_remap(struct request_queue *q, struct bio *bio, 308 dev_t dev, sector_t from, sector_t to) 309 { 310 struct blk_trace *bt = q->blk_trace; 311 struct blk_io_trace_remap r; 312 313 if (likely(!bt)) 314 return; 315 316 r.device = cpu_to_be32(dev); 317 r.device_from = cpu_to_be32(bio->bi_bdev->bd_dev); 318 r.sector = cpu_to_be64(to); 319 320 __blk_add_trace(bt, from, bio->bi_size, bio->bi_rw, BLK_TA_REMAP, !bio_flagged(bio, BIO_UPTODATE), sizeof(r), &r); 321 } 322 323 /** 324 * blk_add_driver_data - Add binary message with driver-specific data 325 * @q: queue the io is for 326 * @rq: io request 327 * @data: driver-specific data 328 * @len: length of driver-specific data 329 * 330 * Description: 331 * Some drivers might want to write driver-specific data per request. 332 * 333 **/ 334 static inline void blk_add_driver_data(struct request_queue *q, 335 struct request *rq, 336 void *data, size_t len) 337 { 338 struct blk_trace *bt = q->blk_trace; 339 340 if (likely(!bt)) 341 return; 342 343 if (blk_pc_request(rq)) 344 __blk_add_trace(bt, 0, rq->data_len, 0, BLK_TA_DRV_DATA, 345 rq->errors, len, data); 346 else 347 __blk_add_trace(bt, rq->hard_sector, rq->hard_nr_sectors << 9, 348 0, BLK_TA_DRV_DATA, rq->errors, len, data); 349 } 350 351 extern int blk_trace_setup(struct request_queue *q, char *name, dev_t dev, 352 char __user *arg); 353 extern int blk_trace_startstop(struct request_queue *q, int start); 354 extern int blk_trace_remove(struct request_queue *q); 355 356 #else /* !CONFIG_BLK_DEV_IO_TRACE */ 357 #define blk_trace_ioctl(bdev, cmd, arg) (-ENOTTY) 358 #define blk_trace_shutdown(q) do { } while (0) 359 #define blk_add_trace_rq(q, rq, what) do { } while (0) 360 #define blk_add_trace_bio(q, rq, what) do { } while (0) 361 #define blk_add_trace_generic(q, rq, rw, what) do { } while (0) 362 #define blk_add_trace_pdu_int(q, what, bio, pdu) do { } while (0) 363 #define blk_add_trace_remap(q, bio, dev, f, t) do {} while (0) 364 #define blk_add_driver_data(q, rq, data, len) do {} while (0) 365 #define do_blk_trace_setup(q, name, dev, buts) (-ENOTTY) 366 #define blk_trace_setup(q, name, dev, arg) (-ENOTTY) 367 #define blk_trace_startstop(q, start) (-ENOTTY) 368 #define blk_trace_remove(q) (-ENOTTY) 369 #define blk_add_trace_msg(q, fmt, ...) do { } while (0) 370 371 #endif /* CONFIG_BLK_DEV_IO_TRACE */ 372 #endif /* __KERNEL__ */ 373 #endif 374