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