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 */ 10 enum 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 */ 34 enum 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 */ 55 enum 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 */ 91 struct 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 */ 108 struct blk_io_trace_remap { 109 __be32 device; 110 __be32 device_from; 111 __be64 sector; 112 }; 113 114 enum { 115 Blktrace_setup = 1, 116 Blktrace_running, 117 Blktrace_stopped, 118 }; 119 120 struct 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 struct dentry *msg_file; 133 atomic_t dropped; 134 }; 135 136 /* 137 * User setup structure passed with BLKTRACESTART 138 */ 139 struct blk_user_trace_setup { 140 char name[BDEVNAME_SIZE]; /* output */ 141 u16 act_mask; /* input */ 142 u32 buf_size; /* input */ 143 u32 buf_nr; /* input */ 144 u64 start_lba; 145 u64 end_lba; 146 u32 pid; 147 }; 148 149 #ifdef __KERNEL__ 150 #if defined(CONFIG_BLK_DEV_IO_TRACE) 151 extern int blk_trace_ioctl(struct block_device *, unsigned, char __user *); 152 extern void blk_trace_shutdown(struct request_queue *); 153 extern void __blk_add_trace(struct blk_trace *, sector_t, int, int, u32, int, int, void *); 154 extern int do_blk_trace_setup(struct request_queue *q, 155 char *name, dev_t dev, struct blk_user_trace_setup *buts); 156 extern void __trace_note_message(struct blk_trace *, const char *fmt, ...); 157 158 /** 159 * blk_add_trace_msg - Add a (simple) message to the blktrace stream 160 * @q: queue the io is for 161 * @fmt: format to print message in 162 * args... Variable argument list for format 163 * 164 * Description: 165 * Records a (simple) message onto the blktrace stream. 166 * 167 * NOTE: BLK_TN_MAX_MSG characters are output at most. 168 * NOTE: Can not use 'static inline' due to presence of var args... 169 * 170 **/ 171 #define blk_add_trace_msg(q, fmt, ...) \ 172 do { \ 173 struct blk_trace *bt = (q)->blk_trace; \ 174 if (unlikely(bt)) \ 175 __trace_note_message(bt, fmt, ##__VA_ARGS__); \ 176 } while (0) 177 #define BLK_TN_MAX_MSG 128 178 179 /** 180 * blk_add_trace_rq - Add a trace for a request oriented action 181 * @q: queue the io is for 182 * @rq: the source request 183 * @what: the action 184 * 185 * Description: 186 * Records an action against a request. Will log the bio offset + size. 187 * 188 **/ 189 static inline void blk_add_trace_rq(struct request_queue *q, struct request *rq, 190 u32 what) 191 { 192 struct blk_trace *bt = q->blk_trace; 193 int rw = rq->cmd_flags & 0x03; 194 195 if (likely(!bt)) 196 return; 197 198 if (blk_pc_request(rq)) { 199 what |= BLK_TC_ACT(BLK_TC_PC); 200 __blk_add_trace(bt, 0, rq->data_len, rw, what, rq->errors, sizeof(rq->cmd), rq->cmd); 201 } else { 202 what |= BLK_TC_ACT(BLK_TC_FS); 203 __blk_add_trace(bt, rq->hard_sector, rq->hard_nr_sectors << 9, rw, what, rq->errors, 0, NULL); 204 } 205 } 206 207 /** 208 * blk_add_trace_bio - Add a trace for a bio oriented action 209 * @q: queue the io is for 210 * @bio: the source bio 211 * @what: the action 212 * 213 * Description: 214 * Records an action against a bio. Will log the bio offset + size. 215 * 216 **/ 217 static inline void blk_add_trace_bio(struct request_queue *q, struct bio *bio, 218 u32 what) 219 { 220 struct blk_trace *bt = q->blk_trace; 221 222 if (likely(!bt)) 223 return; 224 225 __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, !bio_flagged(bio, BIO_UPTODATE), 0, NULL); 226 } 227 228 /** 229 * blk_add_trace_generic - Add a trace for a generic action 230 * @q: queue the io is for 231 * @bio: the source bio 232 * @rw: the data direction 233 * @what: the action 234 * 235 * Description: 236 * Records a simple trace 237 * 238 **/ 239 static inline void blk_add_trace_generic(struct request_queue *q, 240 struct bio *bio, int rw, u32 what) 241 { 242 struct blk_trace *bt = q->blk_trace; 243 244 if (likely(!bt)) 245 return; 246 247 if (bio) 248 blk_add_trace_bio(q, bio, what); 249 else 250 __blk_add_trace(bt, 0, 0, rw, what, 0, 0, NULL); 251 } 252 253 /** 254 * blk_add_trace_pdu_int - Add a trace for a bio with an integer payload 255 * @q: queue the io is for 256 * @what: the action 257 * @bio: the source bio 258 * @pdu: the integer payload 259 * 260 * Description: 261 * Adds a trace with some integer payload. This might be an unplug 262 * option given as the action, with the depth at unplug time given 263 * as the payload 264 * 265 **/ 266 static inline void blk_add_trace_pdu_int(struct request_queue *q, u32 what, 267 struct bio *bio, unsigned int pdu) 268 { 269 struct blk_trace *bt = q->blk_trace; 270 __be64 rpdu = cpu_to_be64(pdu); 271 272 if (likely(!bt)) 273 return; 274 275 if (bio) 276 __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, !bio_flagged(bio, BIO_UPTODATE), sizeof(rpdu), &rpdu); 277 else 278 __blk_add_trace(bt, 0, 0, 0, what, 0, sizeof(rpdu), &rpdu); 279 } 280 281 /** 282 * blk_add_trace_remap - Add a trace for a remap operation 283 * @q: queue the io is for 284 * @bio: the source bio 285 * @dev: target device 286 * @from: source sector 287 * @to: target sector 288 * 289 * Description: 290 * Device mapper or raid target sometimes need to split a bio because 291 * it spans a stripe (or similar). Add a trace for that action. 292 * 293 **/ 294 static inline void blk_add_trace_remap(struct request_queue *q, struct bio *bio, 295 dev_t dev, sector_t from, sector_t to) 296 { 297 struct blk_trace *bt = q->blk_trace; 298 struct blk_io_trace_remap r; 299 300 if (likely(!bt)) 301 return; 302 303 r.device = cpu_to_be32(dev); 304 r.device_from = cpu_to_be32(bio->bi_bdev->bd_dev); 305 r.sector = cpu_to_be64(to); 306 307 __blk_add_trace(bt, from, bio->bi_size, bio->bi_rw, BLK_TA_REMAP, !bio_flagged(bio, BIO_UPTODATE), sizeof(r), &r); 308 } 309 310 extern int blk_trace_setup(struct request_queue *q, char *name, dev_t dev, 311 char __user *arg); 312 extern int blk_trace_startstop(struct request_queue *q, int start); 313 extern int blk_trace_remove(struct request_queue *q); 314 315 #else /* !CONFIG_BLK_DEV_IO_TRACE */ 316 #define blk_trace_ioctl(bdev, cmd, arg) (-ENOTTY) 317 #define blk_trace_shutdown(q) do { } while (0) 318 #define blk_add_trace_rq(q, rq, what) do { } while (0) 319 #define blk_add_trace_bio(q, rq, what) do { } while (0) 320 #define blk_add_trace_generic(q, rq, rw, what) do { } while (0) 321 #define blk_add_trace_pdu_int(q, what, bio, pdu) do { } while (0) 322 #define blk_add_trace_remap(q, bio, dev, f, t) do {} while (0) 323 #define do_blk_trace_setup(q, name, dev, buts) (-ENOTTY) 324 #define blk_trace_setup(q, name, dev, arg) (-ENOTTY) 325 #define blk_trace_startstop(q, start) (-ENOTTY) 326 #define blk_trace_remove(q) (-ENOTTY) 327 #define blk_add_trace_msg(q, fmt, ...) do { } while (0) 328 329 #endif /* CONFIG_BLK_DEV_IO_TRACE */ 330 #endif /* __KERNEL__ */ 331 #endif 332