1 #ifndef BLKTRACE_H 2 #define BLKTRACE_H 3 4 #include <linux/config.h> 5 #include <linux/blkdev.h> 6 #include <linux/relay.h> 7 8 /* 9 * Trace categories 10 */ 11 enum blktrace_cat { 12 BLK_TC_READ = 1 << 0, /* reads */ 13 BLK_TC_WRITE = 1 << 1, /* writes */ 14 BLK_TC_BARRIER = 1 << 2, /* barrier */ 15 BLK_TC_SYNC = 1 << 3, /* barrier */ 16 BLK_TC_QUEUE = 1 << 4, /* queueing/merging */ 17 BLK_TC_REQUEUE = 1 << 5, /* requeueing */ 18 BLK_TC_ISSUE = 1 << 6, /* issue */ 19 BLK_TC_COMPLETE = 1 << 7, /* completions */ 20 BLK_TC_FS = 1 << 8, /* fs requests */ 21 BLK_TC_PC = 1 << 9, /* pc requests */ 22 BLK_TC_NOTIFY = 1 << 10, /* special message */ 23 24 BLK_TC_END = 1 << 15, /* only 16-bits, reminder */ 25 }; 26 27 #define BLK_TC_SHIFT (16) 28 #define BLK_TC_ACT(act) ((act) << BLK_TC_SHIFT) 29 30 /* 31 * Basic trace actions 32 */ 33 enum blktrace_act { 34 __BLK_TA_QUEUE = 1, /* queued */ 35 __BLK_TA_BACKMERGE, /* back merged to existing rq */ 36 __BLK_TA_FRONTMERGE, /* front merge to existing rq */ 37 __BLK_TA_GETRQ, /* allocated new request */ 38 __BLK_TA_SLEEPRQ, /* sleeping on rq allocation */ 39 __BLK_TA_REQUEUE, /* request requeued */ 40 __BLK_TA_ISSUE, /* sent to driver */ 41 __BLK_TA_COMPLETE, /* completed by driver */ 42 __BLK_TA_PLUG, /* queue was plugged */ 43 __BLK_TA_UNPLUG_IO, /* queue was unplugged by io */ 44 __BLK_TA_UNPLUG_TIMER, /* queue was unplugged by timer */ 45 __BLK_TA_INSERT, /* insert request */ 46 __BLK_TA_SPLIT, /* bio was split */ 47 __BLK_TA_BOUNCE, /* bio was bounced */ 48 __BLK_TA_REMAP, /* bio was remapped */ 49 }; 50 51 /* 52 * Trace actions in full. Additionally, read or write is masked 53 */ 54 #define BLK_TA_QUEUE (__BLK_TA_QUEUE | BLK_TC_ACT(BLK_TC_QUEUE)) 55 #define BLK_TA_BACKMERGE (__BLK_TA_BACKMERGE | BLK_TC_ACT(BLK_TC_QUEUE)) 56 #define BLK_TA_FRONTMERGE (__BLK_TA_FRONTMERGE | BLK_TC_ACT(BLK_TC_QUEUE)) 57 #define BLK_TA_GETRQ (__BLK_TA_GETRQ | BLK_TC_ACT(BLK_TC_QUEUE)) 58 #define BLK_TA_SLEEPRQ (__BLK_TA_SLEEPRQ | BLK_TC_ACT(BLK_TC_QUEUE)) 59 #define BLK_TA_REQUEUE (__BLK_TA_REQUEUE | BLK_TC_ACT(BLK_TC_REQUEUE)) 60 #define BLK_TA_ISSUE (__BLK_TA_ISSUE | BLK_TC_ACT(BLK_TC_ISSUE)) 61 #define BLK_TA_COMPLETE (__BLK_TA_COMPLETE| BLK_TC_ACT(BLK_TC_COMPLETE)) 62 #define BLK_TA_PLUG (__BLK_TA_PLUG | BLK_TC_ACT(BLK_TC_QUEUE)) 63 #define BLK_TA_UNPLUG_IO (__BLK_TA_UNPLUG_IO | BLK_TC_ACT(BLK_TC_QUEUE)) 64 #define BLK_TA_UNPLUG_TIMER (__BLK_TA_UNPLUG_TIMER | BLK_TC_ACT(BLK_TC_QUEUE)) 65 #define BLK_TA_INSERT (__BLK_TA_INSERT | BLK_TC_ACT(BLK_TC_QUEUE)) 66 #define BLK_TA_SPLIT (__BLK_TA_SPLIT) 67 #define BLK_TA_BOUNCE (__BLK_TA_BOUNCE) 68 #define BLK_TA_REMAP (__BLK_TA_REMAP | BLK_TC_ACT(BLK_TC_QUEUE)) 69 70 #define BLK_IO_TRACE_MAGIC 0x65617400 71 #define BLK_IO_TRACE_VERSION 0x07 72 73 /* 74 * The trace itself 75 */ 76 struct blk_io_trace { 77 u32 magic; /* MAGIC << 8 | version */ 78 u32 sequence; /* event number */ 79 u64 time; /* in microseconds */ 80 u64 sector; /* disk offset */ 81 u32 bytes; /* transfer length */ 82 u32 action; /* what happened */ 83 u32 pid; /* who did it */ 84 u32 device; /* device number */ 85 u32 cpu; /* on what cpu did it happen */ 86 u16 error; /* completion error */ 87 u16 pdu_len; /* length of data after this trace */ 88 }; 89 90 /* 91 * The remap event 92 */ 93 struct blk_io_trace_remap { 94 u32 device; 95 u32 __pad; 96 u64 sector; 97 }; 98 99 enum { 100 Blktrace_setup = 1, 101 Blktrace_running, 102 Blktrace_stopped, 103 }; 104 105 struct blk_trace { 106 int trace_state; 107 struct rchan *rchan; 108 unsigned long *sequence; 109 u16 act_mask; 110 u64 start_lba; 111 u64 end_lba; 112 u32 pid; 113 u32 dev; 114 struct dentry *dir; 115 struct dentry *dropped_file; 116 atomic_t dropped; 117 }; 118 119 /* 120 * User setup structure passed with BLKTRACESTART 121 */ 122 struct blk_user_trace_setup { 123 char name[BDEVNAME_SIZE]; /* output */ 124 u16 act_mask; /* input */ 125 u32 buf_size; /* input */ 126 u32 buf_nr; /* input */ 127 u64 start_lba; 128 u64 end_lba; 129 u32 pid; 130 }; 131 132 #if defined(CONFIG_BLK_DEV_IO_TRACE) 133 extern int blk_trace_ioctl(struct block_device *, unsigned, char __user *); 134 extern void blk_trace_shutdown(request_queue_t *); 135 extern void __blk_add_trace(struct blk_trace *, sector_t, int, int, u32, int, int, void *); 136 137 /** 138 * blk_add_trace_rq - Add a trace for a request oriented action 139 * @q: queue the io is for 140 * @rq: the source request 141 * @what: the action 142 * 143 * Description: 144 * Records an action against a request. Will log the bio offset + size. 145 * 146 **/ 147 static inline void blk_add_trace_rq(struct request_queue *q, struct request *rq, 148 u32 what) 149 { 150 struct blk_trace *bt = q->blk_trace; 151 int rw = rq->flags & 0x07; 152 153 if (likely(!bt)) 154 return; 155 156 if (blk_pc_request(rq)) { 157 what |= BLK_TC_ACT(BLK_TC_PC); 158 __blk_add_trace(bt, 0, rq->data_len, rw, what, rq->errors, sizeof(rq->cmd), rq->cmd); 159 } else { 160 what |= BLK_TC_ACT(BLK_TC_FS); 161 __blk_add_trace(bt, rq->hard_sector, rq->hard_nr_sectors << 9, rw, what, rq->errors, 0, NULL); 162 } 163 } 164 165 /** 166 * blk_add_trace_bio - Add a trace for a bio oriented action 167 * @q: queue the io is for 168 * @bio: the source bio 169 * @what: the action 170 * 171 * Description: 172 * Records an action against a bio. Will log the bio offset + size. 173 * 174 **/ 175 static inline void blk_add_trace_bio(struct request_queue *q, struct bio *bio, 176 u32 what) 177 { 178 struct blk_trace *bt = q->blk_trace; 179 180 if (likely(!bt)) 181 return; 182 183 __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, !bio_flagged(bio, BIO_UPTODATE), 0, NULL); 184 } 185 186 /** 187 * blk_add_trace_generic - Add a trace for a generic action 188 * @q: queue the io is for 189 * @bio: the source bio 190 * @rw: the data direction 191 * @what: the action 192 * 193 * Description: 194 * Records a simple trace 195 * 196 **/ 197 static inline void blk_add_trace_generic(struct request_queue *q, 198 struct bio *bio, int rw, u32 what) 199 { 200 struct blk_trace *bt = q->blk_trace; 201 202 if (likely(!bt)) 203 return; 204 205 if (bio) 206 blk_add_trace_bio(q, bio, what); 207 else 208 __blk_add_trace(bt, 0, 0, rw, what, 0, 0, NULL); 209 } 210 211 /** 212 * blk_add_trace_pdu_int - Add a trace for a bio with an integer payload 213 * @q: queue the io is for 214 * @what: the action 215 * @bio: the source bio 216 * @pdu: the integer payload 217 * 218 * Description: 219 * Adds a trace with some integer payload. This might be an unplug 220 * option given as the action, with the depth at unplug time given 221 * as the payload 222 * 223 **/ 224 static inline void blk_add_trace_pdu_int(struct request_queue *q, u32 what, 225 struct bio *bio, unsigned int pdu) 226 { 227 struct blk_trace *bt = q->blk_trace; 228 u64 rpdu = cpu_to_be64(pdu); 229 230 if (likely(!bt)) 231 return; 232 233 if (bio) 234 __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, !bio_flagged(bio, BIO_UPTODATE), sizeof(rpdu), &rpdu); 235 else 236 __blk_add_trace(bt, 0, 0, 0, what, 0, sizeof(rpdu), &rpdu); 237 } 238 239 /** 240 * blk_add_trace_remap - Add a trace for a remap operation 241 * @q: queue the io is for 242 * @bio: the source bio 243 * @dev: target device 244 * @from: source sector 245 * @to: target sector 246 * 247 * Description: 248 * Device mapper or raid target sometimes need to split a bio because 249 * it spans a stripe (or similar). Add a trace for that action. 250 * 251 **/ 252 static inline void blk_add_trace_remap(struct request_queue *q, struct bio *bio, 253 dev_t dev, sector_t from, sector_t to) 254 { 255 struct blk_trace *bt = q->blk_trace; 256 struct blk_io_trace_remap r; 257 258 if (likely(!bt)) 259 return; 260 261 r.device = cpu_to_be32(dev); 262 r.sector = cpu_to_be64(to); 263 264 __blk_add_trace(bt, from, bio->bi_size, bio->bi_rw, BLK_TA_REMAP, !bio_flagged(bio, BIO_UPTODATE), sizeof(r), &r); 265 } 266 267 #else /* !CONFIG_BLK_DEV_IO_TRACE */ 268 #define blk_trace_ioctl(bdev, cmd, arg) (-ENOTTY) 269 #define blk_trace_shutdown(q) do { } while (0) 270 #define blk_add_trace_rq(q, rq, what) do { } while (0) 271 #define blk_add_trace_bio(q, rq, what) do { } while (0) 272 #define blk_add_trace_generic(q, rq, rw, what) do { } while (0) 273 #define blk_add_trace_pdu_int(q, what, bio, pdu) do { } while (0) 274 #define blk_add_trace_remap(q, bio, dev, f, t) do {} while (0) 275 #endif /* CONFIG_BLK_DEV_IO_TRACE */ 276 277 #endif 278