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 }; 59 60 61 /* 62 * Trace actions in full. Additionally, read or write is masked 63 */ 64 #define BLK_TA_QUEUE (__BLK_TA_QUEUE | BLK_TC_ACT(BLK_TC_QUEUE)) 65 #define BLK_TA_BACKMERGE (__BLK_TA_BACKMERGE | BLK_TC_ACT(BLK_TC_QUEUE)) 66 #define BLK_TA_FRONTMERGE (__BLK_TA_FRONTMERGE | BLK_TC_ACT(BLK_TC_QUEUE)) 67 #define BLK_TA_GETRQ (__BLK_TA_GETRQ | BLK_TC_ACT(BLK_TC_QUEUE)) 68 #define BLK_TA_SLEEPRQ (__BLK_TA_SLEEPRQ | BLK_TC_ACT(BLK_TC_QUEUE)) 69 #define BLK_TA_REQUEUE (__BLK_TA_REQUEUE | BLK_TC_ACT(BLK_TC_REQUEUE)) 70 #define BLK_TA_ISSUE (__BLK_TA_ISSUE | BLK_TC_ACT(BLK_TC_ISSUE)) 71 #define BLK_TA_COMPLETE (__BLK_TA_COMPLETE| BLK_TC_ACT(BLK_TC_COMPLETE)) 72 #define BLK_TA_PLUG (__BLK_TA_PLUG | BLK_TC_ACT(BLK_TC_QUEUE)) 73 #define BLK_TA_UNPLUG_IO (__BLK_TA_UNPLUG_IO | BLK_TC_ACT(BLK_TC_QUEUE)) 74 #define BLK_TA_UNPLUG_TIMER (__BLK_TA_UNPLUG_TIMER | BLK_TC_ACT(BLK_TC_QUEUE)) 75 #define BLK_TA_INSERT (__BLK_TA_INSERT | BLK_TC_ACT(BLK_TC_QUEUE)) 76 #define BLK_TA_SPLIT (__BLK_TA_SPLIT) 77 #define BLK_TA_BOUNCE (__BLK_TA_BOUNCE) 78 #define BLK_TA_REMAP (__BLK_TA_REMAP | BLK_TC_ACT(BLK_TC_QUEUE)) 79 80 #define BLK_TN_PROCESS (__BLK_TN_PROCESS | BLK_TC_ACT(BLK_TC_NOTIFY)) 81 #define BLK_TN_TIMESTAMP (__BLK_TN_TIMESTAMP | BLK_TC_ACT(BLK_TC_NOTIFY)) 82 83 #define BLK_IO_TRACE_MAGIC 0x65617400 84 #define BLK_IO_TRACE_VERSION 0x07 85 86 /* 87 * The trace itself 88 */ 89 struct blk_io_trace { 90 u32 magic; /* MAGIC << 8 | version */ 91 u32 sequence; /* event number */ 92 u64 time; /* in microseconds */ 93 u64 sector; /* disk offset */ 94 u32 bytes; /* transfer length */ 95 u32 action; /* what happened */ 96 u32 pid; /* who did it */ 97 u32 device; /* device number */ 98 u32 cpu; /* on what cpu did it happen */ 99 u16 error; /* completion error */ 100 u16 pdu_len; /* length of data after this trace */ 101 }; 102 103 /* 104 * The remap event 105 */ 106 struct blk_io_trace_remap { 107 __be32 device; 108 __be32 device_from; 109 __be64 sector; 110 }; 111 112 enum { 113 Blktrace_setup = 1, 114 Blktrace_running, 115 Blktrace_stopped, 116 }; 117 118 struct blk_trace { 119 int trace_state; 120 struct rchan *rchan; 121 unsigned long *sequence; 122 u16 act_mask; 123 u64 start_lba; 124 u64 end_lba; 125 u32 pid; 126 u32 dev; 127 struct dentry *dir; 128 struct dentry *dropped_file; 129 atomic_t dropped; 130 }; 131 132 /* 133 * User setup structure passed with BLKTRACESTART 134 */ 135 struct blk_user_trace_setup { 136 char name[BDEVNAME_SIZE]; /* output */ 137 u16 act_mask; /* input */ 138 u32 buf_size; /* input */ 139 u32 buf_nr; /* input */ 140 u64 start_lba; 141 u64 end_lba; 142 u32 pid; 143 }; 144 145 #if defined(CONFIG_BLK_DEV_IO_TRACE) 146 extern int blk_trace_ioctl(struct block_device *, unsigned, char __user *); 147 extern void blk_trace_shutdown(struct request_queue *); 148 extern void __blk_add_trace(struct blk_trace *, sector_t, int, int, u32, int, int, void *); 149 150 /** 151 * blk_add_trace_rq - Add a trace for a request oriented action 152 * @q: queue the io is for 153 * @rq: the source request 154 * @what: the action 155 * 156 * Description: 157 * Records an action against a request. Will log the bio offset + size. 158 * 159 **/ 160 static inline void blk_add_trace_rq(struct request_queue *q, struct request *rq, 161 u32 what) 162 { 163 struct blk_trace *bt = q->blk_trace; 164 int rw = rq->cmd_flags & 0x03; 165 166 if (likely(!bt)) 167 return; 168 169 if (blk_pc_request(rq)) { 170 what |= BLK_TC_ACT(BLK_TC_PC); 171 __blk_add_trace(bt, 0, rq->data_len, rw, what, rq->errors, sizeof(rq->cmd), rq->cmd); 172 } else { 173 what |= BLK_TC_ACT(BLK_TC_FS); 174 __blk_add_trace(bt, rq->hard_sector, rq->hard_nr_sectors << 9, rw, what, rq->errors, 0, NULL); 175 } 176 } 177 178 /** 179 * blk_add_trace_bio - Add a trace for a bio oriented action 180 * @q: queue the io is for 181 * @bio: the source bio 182 * @what: the action 183 * 184 * Description: 185 * Records an action against a bio. Will log the bio offset + size. 186 * 187 **/ 188 static inline void blk_add_trace_bio(struct request_queue *q, struct bio *bio, 189 u32 what) 190 { 191 struct blk_trace *bt = q->blk_trace; 192 193 if (likely(!bt)) 194 return; 195 196 __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, !bio_flagged(bio, BIO_UPTODATE), 0, NULL); 197 } 198 199 /** 200 * blk_add_trace_generic - Add a trace for a generic action 201 * @q: queue the io is for 202 * @bio: the source bio 203 * @rw: the data direction 204 * @what: the action 205 * 206 * Description: 207 * Records a simple trace 208 * 209 **/ 210 static inline void blk_add_trace_generic(struct request_queue *q, 211 struct bio *bio, int rw, u32 what) 212 { 213 struct blk_trace *bt = q->blk_trace; 214 215 if (likely(!bt)) 216 return; 217 218 if (bio) 219 blk_add_trace_bio(q, bio, what); 220 else 221 __blk_add_trace(bt, 0, 0, rw, what, 0, 0, NULL); 222 } 223 224 /** 225 * blk_add_trace_pdu_int - Add a trace for a bio with an integer payload 226 * @q: queue the io is for 227 * @what: the action 228 * @bio: the source bio 229 * @pdu: the integer payload 230 * 231 * Description: 232 * Adds a trace with some integer payload. This might be an unplug 233 * option given as the action, with the depth at unplug time given 234 * as the payload 235 * 236 **/ 237 static inline void blk_add_trace_pdu_int(struct request_queue *q, u32 what, 238 struct bio *bio, unsigned int pdu) 239 { 240 struct blk_trace *bt = q->blk_trace; 241 __be64 rpdu = cpu_to_be64(pdu); 242 243 if (likely(!bt)) 244 return; 245 246 if (bio) 247 __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, !bio_flagged(bio, BIO_UPTODATE), sizeof(rpdu), &rpdu); 248 else 249 __blk_add_trace(bt, 0, 0, 0, what, 0, sizeof(rpdu), &rpdu); 250 } 251 252 /** 253 * blk_add_trace_remap - Add a trace for a remap operation 254 * @q: queue the io is for 255 * @bio: the source bio 256 * @dev: target device 257 * @from: source sector 258 * @to: target sector 259 * 260 * Description: 261 * Device mapper or raid target sometimes need to split a bio because 262 * it spans a stripe (or similar). Add a trace for that action. 263 * 264 **/ 265 static inline void blk_add_trace_remap(struct request_queue *q, struct bio *bio, 266 dev_t dev, sector_t from, sector_t to) 267 { 268 struct blk_trace *bt = q->blk_trace; 269 struct blk_io_trace_remap r; 270 271 if (likely(!bt)) 272 return; 273 274 r.device = cpu_to_be32(dev); 275 r.device_from = cpu_to_be32(bio->bi_bdev->bd_dev); 276 r.sector = cpu_to_be64(to); 277 278 __blk_add_trace(bt, from, bio->bi_size, bio->bi_rw, BLK_TA_REMAP, !bio_flagged(bio, BIO_UPTODATE), sizeof(r), &r); 279 } 280 281 #else /* !CONFIG_BLK_DEV_IO_TRACE */ 282 #define blk_trace_ioctl(bdev, cmd, arg) (-ENOTTY) 283 #define blk_trace_shutdown(q) do { } while (0) 284 #define blk_add_trace_rq(q, rq, what) do { } while (0) 285 #define blk_add_trace_bio(q, rq, what) do { } while (0) 286 #define blk_add_trace_generic(q, rq, rw, what) do { } while (0) 287 #define blk_add_trace_pdu_int(q, what, bio, pdu) do { } while (0) 288 #define blk_add_trace_remap(q, bio, dev, f, t) do {} while (0) 289 #endif /* CONFIG_BLK_DEV_IO_TRACE */ 290 291 #endif 292