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, /* barrier */ 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 23 BLK_TC_END = 1 << 15, /* only 16-bits, reminder */ 24 }; 25 26 #define BLK_TC_SHIFT (16) 27 #define BLK_TC_ACT(act) ((act) << BLK_TC_SHIFT) 28 29 /* 30 * Basic trace actions 31 */ 32 enum blktrace_act { 33 __BLK_TA_QUEUE = 1, /* queued */ 34 __BLK_TA_BACKMERGE, /* back merged to existing rq */ 35 __BLK_TA_FRONTMERGE, /* front merge to existing rq */ 36 __BLK_TA_GETRQ, /* allocated new request */ 37 __BLK_TA_SLEEPRQ, /* sleeping on rq allocation */ 38 __BLK_TA_REQUEUE, /* request requeued */ 39 __BLK_TA_ISSUE, /* sent to driver */ 40 __BLK_TA_COMPLETE, /* completed by driver */ 41 __BLK_TA_PLUG, /* queue was plugged */ 42 __BLK_TA_UNPLUG_IO, /* queue was unplugged by io */ 43 __BLK_TA_UNPLUG_TIMER, /* queue was unplugged by timer */ 44 __BLK_TA_INSERT, /* insert request */ 45 __BLK_TA_SPLIT, /* bio was split */ 46 __BLK_TA_BOUNCE, /* bio was bounced */ 47 __BLK_TA_REMAP, /* bio was remapped */ 48 }; 49 50 /* 51 * Trace actions in full. Additionally, read or write is masked 52 */ 53 #define BLK_TA_QUEUE (__BLK_TA_QUEUE | BLK_TC_ACT(BLK_TC_QUEUE)) 54 #define BLK_TA_BACKMERGE (__BLK_TA_BACKMERGE | BLK_TC_ACT(BLK_TC_QUEUE)) 55 #define BLK_TA_FRONTMERGE (__BLK_TA_FRONTMERGE | BLK_TC_ACT(BLK_TC_QUEUE)) 56 #define BLK_TA_GETRQ (__BLK_TA_GETRQ | BLK_TC_ACT(BLK_TC_QUEUE)) 57 #define BLK_TA_SLEEPRQ (__BLK_TA_SLEEPRQ | BLK_TC_ACT(BLK_TC_QUEUE)) 58 #define BLK_TA_REQUEUE (__BLK_TA_REQUEUE | BLK_TC_ACT(BLK_TC_REQUEUE)) 59 #define BLK_TA_ISSUE (__BLK_TA_ISSUE | BLK_TC_ACT(BLK_TC_ISSUE)) 60 #define BLK_TA_COMPLETE (__BLK_TA_COMPLETE| BLK_TC_ACT(BLK_TC_COMPLETE)) 61 #define BLK_TA_PLUG (__BLK_TA_PLUG | BLK_TC_ACT(BLK_TC_QUEUE)) 62 #define BLK_TA_UNPLUG_IO (__BLK_TA_UNPLUG_IO | BLK_TC_ACT(BLK_TC_QUEUE)) 63 #define BLK_TA_UNPLUG_TIMER (__BLK_TA_UNPLUG_TIMER | BLK_TC_ACT(BLK_TC_QUEUE)) 64 #define BLK_TA_INSERT (__BLK_TA_INSERT | BLK_TC_ACT(BLK_TC_QUEUE)) 65 #define BLK_TA_SPLIT (__BLK_TA_SPLIT) 66 #define BLK_TA_BOUNCE (__BLK_TA_BOUNCE) 67 #define BLK_TA_REMAP (__BLK_TA_REMAP | BLK_TC_ACT(BLK_TC_QUEUE)) 68 69 #define BLK_IO_TRACE_MAGIC 0x65617400 70 #define BLK_IO_TRACE_VERSION 0x07 71 72 /* 73 * The trace itself 74 */ 75 struct blk_io_trace { 76 u32 magic; /* MAGIC << 8 | version */ 77 u32 sequence; /* event number */ 78 u64 time; /* in microseconds */ 79 u64 sector; /* disk offset */ 80 u32 bytes; /* transfer length */ 81 u32 action; /* what happened */ 82 u32 pid; /* who did it */ 83 u32 device; /* device number */ 84 u32 cpu; /* on what cpu did it happen */ 85 u16 error; /* completion error */ 86 u16 pdu_len; /* length of data after this trace */ 87 }; 88 89 /* 90 * The remap event 91 */ 92 struct blk_io_trace_remap { 93 __be32 device; 94 u32 __pad; 95 __be64 sector; 96 }; 97 98 enum { 99 Blktrace_setup = 1, 100 Blktrace_running, 101 Blktrace_stopped, 102 }; 103 104 struct blk_trace { 105 int trace_state; 106 struct rchan *rchan; 107 unsigned long *sequence; 108 u16 act_mask; 109 u64 start_lba; 110 u64 end_lba; 111 u32 pid; 112 u32 dev; 113 struct dentry *dir; 114 struct dentry *dropped_file; 115 atomic_t dropped; 116 }; 117 118 /* 119 * User setup structure passed with BLKTRACESTART 120 */ 121 struct blk_user_trace_setup { 122 char name[BDEVNAME_SIZE]; /* output */ 123 u16 act_mask; /* input */ 124 u32 buf_size; /* input */ 125 u32 buf_nr; /* input */ 126 u64 start_lba; 127 u64 end_lba; 128 u32 pid; 129 }; 130 131 #if defined(CONFIG_BLK_DEV_IO_TRACE) 132 extern int blk_trace_ioctl(struct block_device *, unsigned, char __user *); 133 extern void blk_trace_shutdown(request_queue_t *); 134 extern void __blk_add_trace(struct blk_trace *, sector_t, int, int, u32, int, int, void *); 135 136 /** 137 * blk_add_trace_rq - Add a trace for a request oriented action 138 * @q: queue the io is for 139 * @rq: the source request 140 * @what: the action 141 * 142 * Description: 143 * Records an action against a request. Will log the bio offset + size. 144 * 145 **/ 146 static inline void blk_add_trace_rq(struct request_queue *q, struct request *rq, 147 u32 what) 148 { 149 struct blk_trace *bt = q->blk_trace; 150 int rw = rq->flags & 0x07; 151 152 if (likely(!bt)) 153 return; 154 155 if (blk_pc_request(rq)) { 156 what |= BLK_TC_ACT(BLK_TC_PC); 157 __blk_add_trace(bt, 0, rq->data_len, rw, what, rq->errors, sizeof(rq->cmd), rq->cmd); 158 } else { 159 what |= BLK_TC_ACT(BLK_TC_FS); 160 __blk_add_trace(bt, rq->hard_sector, rq->hard_nr_sectors << 9, rw, what, rq->errors, 0, NULL); 161 } 162 } 163 164 /** 165 * blk_add_trace_bio - Add a trace for a bio oriented action 166 * @q: queue the io is for 167 * @bio: the source bio 168 * @what: the action 169 * 170 * Description: 171 * Records an action against a bio. Will log the bio offset + size. 172 * 173 **/ 174 static inline void blk_add_trace_bio(struct request_queue *q, struct bio *bio, 175 u32 what) 176 { 177 struct blk_trace *bt = q->blk_trace; 178 179 if (likely(!bt)) 180 return; 181 182 __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, !bio_flagged(bio, BIO_UPTODATE), 0, NULL); 183 } 184 185 /** 186 * blk_add_trace_generic - Add a trace for a generic action 187 * @q: queue the io is for 188 * @bio: the source bio 189 * @rw: the data direction 190 * @what: the action 191 * 192 * Description: 193 * Records a simple trace 194 * 195 **/ 196 static inline void blk_add_trace_generic(struct request_queue *q, 197 struct bio *bio, int rw, u32 what) 198 { 199 struct blk_trace *bt = q->blk_trace; 200 201 if (likely(!bt)) 202 return; 203 204 if (bio) 205 blk_add_trace_bio(q, bio, what); 206 else 207 __blk_add_trace(bt, 0, 0, rw, what, 0, 0, NULL); 208 } 209 210 /** 211 * blk_add_trace_pdu_int - Add a trace for a bio with an integer payload 212 * @q: queue the io is for 213 * @what: the action 214 * @bio: the source bio 215 * @pdu: the integer payload 216 * 217 * Description: 218 * Adds a trace with some integer payload. This might be an unplug 219 * option given as the action, with the depth at unplug time given 220 * as the payload 221 * 222 **/ 223 static inline void blk_add_trace_pdu_int(struct request_queue *q, u32 what, 224 struct bio *bio, unsigned int pdu) 225 { 226 struct blk_trace *bt = q->blk_trace; 227 __be64 rpdu = cpu_to_be64(pdu); 228 229 if (likely(!bt)) 230 return; 231 232 if (bio) 233 __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, !bio_flagged(bio, BIO_UPTODATE), sizeof(rpdu), &rpdu); 234 else 235 __blk_add_trace(bt, 0, 0, 0, what, 0, sizeof(rpdu), &rpdu); 236 } 237 238 /** 239 * blk_add_trace_remap - Add a trace for a remap operation 240 * @q: queue the io is for 241 * @bio: the source bio 242 * @dev: target device 243 * @from: source sector 244 * @to: target sector 245 * 246 * Description: 247 * Device mapper or raid target sometimes need to split a bio because 248 * it spans a stripe (or similar). Add a trace for that action. 249 * 250 **/ 251 static inline void blk_add_trace_remap(struct request_queue *q, struct bio *bio, 252 dev_t dev, sector_t from, sector_t to) 253 { 254 struct blk_trace *bt = q->blk_trace; 255 struct blk_io_trace_remap r; 256 257 if (likely(!bt)) 258 return; 259 260 r.device = cpu_to_be32(dev); 261 r.sector = cpu_to_be64(to); 262 263 __blk_add_trace(bt, from, bio->bi_size, bio->bi_rw, BLK_TA_REMAP, !bio_flagged(bio, BIO_UPTODATE), sizeof(r), &r); 264 } 265 266 #else /* !CONFIG_BLK_DEV_IO_TRACE */ 267 #define blk_trace_ioctl(bdev, cmd, arg) (-ENOTTY) 268 #define blk_trace_shutdown(q) do { } while (0) 269 #define blk_add_trace_rq(q, rq, what) do { } while (0) 270 #define blk_add_trace_bio(q, rq, what) do { } while (0) 271 #define blk_add_trace_generic(q, rq, rw, what) do { } while (0) 272 #define blk_add_trace_pdu_int(q, what, bio, pdu) do { } while (0) 273 #define blk_add_trace_remap(q, bio, dev, f, t) do {} while (0) 274 #endif /* CONFIG_BLK_DEV_IO_TRACE */ 275 276 #endif 277