#ifndef BLKTRACE_H #define BLKTRACE_H #include <linux/blkdev.h> #include <linux/relay.h> /* * Trace categories */ enum blktrace_cat { BLK_TC_READ = 1 << 0, /* reads */ BLK_TC_WRITE = 1 << 1, /* writes */ BLK_TC_BARRIER = 1 << 2, /* barrier */ BLK_TC_SYNC = 1 << 3, /* sync IO */ BLK_TC_QUEUE = 1 << 4, /* queueing/merging */ BLK_TC_REQUEUE = 1 << 5, /* requeueing */ BLK_TC_ISSUE = 1 << 6, /* issue */ BLK_TC_COMPLETE = 1 << 7, /* completions */ BLK_TC_FS = 1 << 8, /* fs requests */ BLK_TC_PC = 1 << 9, /* pc requests */ BLK_TC_NOTIFY = 1 << 10, /* special message */ BLK_TC_AHEAD = 1 << 11, /* readahead */ BLK_TC_META = 1 << 12, /* metadata */ BLK_TC_DISCARD = 1 << 13, /* discard requests */ BLK_TC_END = 1 << 15, /* only 16-bits, reminder */ }; #define BLK_TC_SHIFT (16) #define BLK_TC_ACT(act) ((act) << BLK_TC_SHIFT) /* * Basic trace actions */ enum blktrace_act { __BLK_TA_QUEUE = 1, /* queued */ __BLK_TA_BACKMERGE, /* back merged to existing rq */ __BLK_TA_FRONTMERGE, /* front merge to existing rq */ __BLK_TA_GETRQ, /* allocated new request */ __BLK_TA_SLEEPRQ, /* sleeping on rq allocation */ __BLK_TA_REQUEUE, /* request requeued */ __BLK_TA_ISSUE, /* sent to driver */ __BLK_TA_COMPLETE, /* completed by driver */ __BLK_TA_PLUG, /* queue was plugged */ __BLK_TA_UNPLUG_IO, /* queue was unplugged by io */ __BLK_TA_UNPLUG_TIMER, /* queue was unplugged by timer */ __BLK_TA_INSERT, /* insert request */ __BLK_TA_SPLIT, /* bio was split */ __BLK_TA_BOUNCE, /* bio was bounced */ __BLK_TA_REMAP, /* bio was remapped */ }; /* * Notify events. */ enum blktrace_notify { __BLK_TN_PROCESS = 0, /* establish pid/name mapping */ __BLK_TN_TIMESTAMP, /* include system clock */ __BLK_TN_MESSAGE, /* Character string message */ }; /* * Trace actions in full. Additionally, read or write is masked */ #define BLK_TA_QUEUE (__BLK_TA_QUEUE | BLK_TC_ACT(BLK_TC_QUEUE)) #define BLK_TA_BACKMERGE (__BLK_TA_BACKMERGE | BLK_TC_ACT(BLK_TC_QUEUE)) #define BLK_TA_FRONTMERGE (__BLK_TA_FRONTMERGE | BLK_TC_ACT(BLK_TC_QUEUE)) #define BLK_TA_GETRQ (__BLK_TA_GETRQ | BLK_TC_ACT(BLK_TC_QUEUE)) #define BLK_TA_SLEEPRQ (__BLK_TA_SLEEPRQ | BLK_TC_ACT(BLK_TC_QUEUE)) #define BLK_TA_REQUEUE (__BLK_TA_REQUEUE | BLK_TC_ACT(BLK_TC_REQUEUE)) #define BLK_TA_ISSUE (__BLK_TA_ISSUE | BLK_TC_ACT(BLK_TC_ISSUE)) #define BLK_TA_COMPLETE (__BLK_TA_COMPLETE| BLK_TC_ACT(BLK_TC_COMPLETE)) #define BLK_TA_PLUG (__BLK_TA_PLUG | BLK_TC_ACT(BLK_TC_QUEUE)) #define BLK_TA_UNPLUG_IO (__BLK_TA_UNPLUG_IO | BLK_TC_ACT(BLK_TC_QUEUE)) #define BLK_TA_UNPLUG_TIMER (__BLK_TA_UNPLUG_TIMER | BLK_TC_ACT(BLK_TC_QUEUE)) #define BLK_TA_INSERT (__BLK_TA_INSERT | BLK_TC_ACT(BLK_TC_QUEUE)) #define BLK_TA_SPLIT (__BLK_TA_SPLIT) #define BLK_TA_BOUNCE (__BLK_TA_BOUNCE) #define BLK_TA_REMAP (__BLK_TA_REMAP | BLK_TC_ACT(BLK_TC_QUEUE)) #define BLK_TN_PROCESS (__BLK_TN_PROCESS | BLK_TC_ACT(BLK_TC_NOTIFY)) #define BLK_TN_TIMESTAMP (__BLK_TN_TIMESTAMP | BLK_TC_ACT(BLK_TC_NOTIFY)) #define BLK_TN_MESSAGE (__BLK_TN_MESSAGE | BLK_TC_ACT(BLK_TC_NOTIFY)) #define BLK_IO_TRACE_MAGIC 0x65617400 #define BLK_IO_TRACE_VERSION 0x07 /* * The trace itself */ struct blk_io_trace { u32 magic; /* MAGIC << 8 | version */ u32 sequence; /* event number */ u64 time; /* in microseconds */ u64 sector; /* disk offset */ u32 bytes; /* transfer length */ u32 action; /* what happened */ u32 pid; /* who did it */ u32 device; /* device number */ u32 cpu; /* on what cpu did it happen */ u16 error; /* completion error */ u16 pdu_len; /* length of data after this trace */ }; /* * The remap event */ struct blk_io_trace_remap { __be32 device; __be32 device_from; __be64 sector; }; enum { Blktrace_setup = 1, Blktrace_running, Blktrace_stopped, }; struct blk_trace { int trace_state; struct rchan *rchan; unsigned long *sequence; unsigned char *msg_data; u16 act_mask; u64 start_lba; u64 end_lba; u32 pid; u32 dev; struct dentry *dir; struct dentry *dropped_file; struct dentry *msg_file; atomic_t dropped; }; /* * User setup structure passed with BLKTRACESTART */ struct blk_user_trace_setup { char name[BDEVNAME_SIZE]; /* output */ u16 act_mask; /* input */ u32 buf_size; /* input */ u32 buf_nr; /* input */ u64 start_lba; u64 end_lba; u32 pid; }; #ifdef __KERNEL__ #if defined(CONFIG_BLK_DEV_IO_TRACE) extern int blk_trace_ioctl(struct block_device *, unsigned, char __user *); extern void blk_trace_shutdown(struct request_queue *); extern void __blk_add_trace(struct blk_trace *, sector_t, int, int, u32, int, int, void *); extern int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev, struct blk_user_trace_setup *buts); extern void __trace_note_message(struct blk_trace *, const char *fmt, ...); /** * blk_add_trace_msg - Add a (simple) message to the blktrace stream * @q: queue the io is for * @fmt: format to print message in * args... Variable argument list for format * * Description: * Records a (simple) message onto the blktrace stream. * * NOTE: BLK_TN_MAX_MSG characters are output at most. * NOTE: Can not use 'static inline' due to presence of var args... * **/ #define blk_add_trace_msg(q, fmt, ...) \ do { \ struct blk_trace *bt = (q)->blk_trace; \ if (unlikely(bt)) \ __trace_note_message(bt, fmt, ##__VA_ARGS__); \ } while (0) #define BLK_TN_MAX_MSG 128 /** * blk_add_trace_rq - Add a trace for a request oriented action * @q: queue the io is for * @rq: the source request * @what: the action * * Description: * Records an action against a request. Will log the bio offset + size. * **/ static inline void blk_add_trace_rq(struct request_queue *q, struct request *rq, u32 what) { struct blk_trace *bt = q->blk_trace; int rw = rq->cmd_flags & 0x03; if (likely(!bt)) return; if (blk_discard_rq(rq)) rw |= (1 << BIO_RW_DISCARD); if (blk_pc_request(rq)) { what |= BLK_TC_ACT(BLK_TC_PC); __blk_add_trace(bt, 0, rq->data_len, rw, what, rq->errors, sizeof(rq->cmd), rq->cmd); } else { what |= BLK_TC_ACT(BLK_TC_FS); __blk_add_trace(bt, rq->hard_sector, rq->hard_nr_sectors << 9, rw, what, rq->errors, 0, NULL); } } /** * blk_add_trace_bio - Add a trace for a bio oriented action * @q: queue the io is for * @bio: the source bio * @what: the action * * Description: * Records an action against a bio. Will log the bio offset + size. * **/ static inline void blk_add_trace_bio(struct request_queue *q, struct bio *bio, u32 what) { struct blk_trace *bt = q->blk_trace; if (likely(!bt)) return; __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, !bio_flagged(bio, BIO_UPTODATE), 0, NULL); } /** * blk_add_trace_generic - Add a trace for a generic action * @q: queue the io is for * @bio: the source bio * @rw: the data direction * @what: the action * * Description: * Records a simple trace * **/ static inline void blk_add_trace_generic(struct request_queue *q, struct bio *bio, int rw, u32 what) { struct blk_trace *bt = q->blk_trace; if (likely(!bt)) return; if (bio) blk_add_trace_bio(q, bio, what); else __blk_add_trace(bt, 0, 0, rw, what, 0, 0, NULL); } /** * blk_add_trace_pdu_int - Add a trace for a bio with an integer payload * @q: queue the io is for * @what: the action * @bio: the source bio * @pdu: the integer payload * * Description: * Adds a trace with some integer payload. This might be an unplug * option given as the action, with the depth at unplug time given * as the payload * **/ static inline void blk_add_trace_pdu_int(struct request_queue *q, u32 what, struct bio *bio, unsigned int pdu) { struct blk_trace *bt = q->blk_trace; __be64 rpdu = cpu_to_be64(pdu); if (likely(!bt)) return; if (bio) __blk_add_trace(bt, bio->bi_sector, bio->bi_size, bio->bi_rw, what, !bio_flagged(bio, BIO_UPTODATE), sizeof(rpdu), &rpdu); else __blk_add_trace(bt, 0, 0, 0, what, 0, sizeof(rpdu), &rpdu); } /** * blk_add_trace_remap - Add a trace for a remap operation * @q: queue the io is for * @bio: the source bio * @dev: target device * @from: source sector * @to: target sector * * Description: * Device mapper or raid target sometimes need to split a bio because * it spans a stripe (or similar). Add a trace for that action. * **/ static inline void blk_add_trace_remap(struct request_queue *q, struct bio *bio, dev_t dev, sector_t from, sector_t to) { struct blk_trace *bt = q->blk_trace; struct blk_io_trace_remap r; if (likely(!bt)) return; r.device = cpu_to_be32(dev); r.device_from = cpu_to_be32(bio->bi_bdev->bd_dev); r.sector = cpu_to_be64(to); __blk_add_trace(bt, from, bio->bi_size, bio->bi_rw, BLK_TA_REMAP, !bio_flagged(bio, BIO_UPTODATE), sizeof(r), &r); } extern int blk_trace_setup(struct request_queue *q, char *name, dev_t dev, char __user *arg); extern int blk_trace_startstop(struct request_queue *q, int start); extern int blk_trace_remove(struct request_queue *q); #else /* !CONFIG_BLK_DEV_IO_TRACE */ #define blk_trace_ioctl(bdev, cmd, arg) (-ENOTTY) #define blk_trace_shutdown(q) do { } while (0) #define blk_add_trace_rq(q, rq, what) do { } while (0) #define blk_add_trace_bio(q, rq, what) do { } while (0) #define blk_add_trace_generic(q, rq, rw, what) do { } while (0) #define blk_add_trace_pdu_int(q, what, bio, pdu) do { } while (0) #define blk_add_trace_remap(q, bio, dev, f, t) do {} while (0) #define do_blk_trace_setup(q, name, dev, buts) (-ENOTTY) #define blk_trace_setup(q, name, dev, arg) (-ENOTTY) #define blk_trace_startstop(q, start) (-ENOTTY) #define blk_trace_remove(q) (-ENOTTY) #define blk_add_trace_msg(q, fmt, ...) do { } while (0) #endif /* CONFIG_BLK_DEV_IO_TRACE */ #endif /* __KERNEL__ */ #endif