include/linux/blktrace_api.h

   1 #ifndef BLKTRACE_H
   2 #define BLKTRACE_H
   3
   4 #include <linux/types.h>
   5 #ifdef __KERNEL__
   6 #include <linux/blkdev.h>
   7 #include <linux/relay.h>
   8 #include <linux/compat.h>
   9 #endif
  10
  11 /*
  12  * Trace categories
  13  */
  14 enum blktrace_cat {
  15         BLK_TC_READ     = 1 << 0,       /* reads */
  16         BLK_TC_WRITE    = 1 << 1,       /* writes */
  17         BLK_TC_BARRIER  = 1 << 2,       /* barrier */
  18         BLK_TC_SYNC     = 1 << 3,       /* sync IO */
  19         BLK_TC_SYNCIO   = BLK_TC_SYNC,
  20         BLK_TC_QUEUE    = 1 << 4,       /* queueing/merging */
  21         BLK_TC_REQUEUE  = 1 << 5,       /* requeueing */
  22         BLK_TC_ISSUE    = 1 << 6,       /* issue */
  23         BLK_TC_COMPLETE = 1 << 7,       /* completions */
  24         BLK_TC_FS       = 1 << 8,       /* fs requests */
  25         BLK_TC_PC       = 1 << 9,       /* pc requests */
  26         BLK_TC_NOTIFY   = 1 << 10,      /* special message */
  27         BLK_TC_AHEAD    = 1 << 11,      /* readahead */
  28         BLK_TC_META     = 1 << 12,      /* metadata */
  29         BLK_TC_DISCARD  = 1 << 13,      /* discard requests */
  30         BLK_TC_DRV_DATA = 1 << 14,      /* binary per-driver data */
  31
  32         BLK_TC_END      = 1 << 15,      /* only 16-bits, reminder */
  33 };
  34
  35 #define BLK_TC_SHIFT            (16)
  36 #define BLK_TC_ACT(act)         ((act) << BLK_TC_SHIFT)
  37
  38 /*
  39  * Basic trace actions
  40  */
  41 enum blktrace_act {
  42         __BLK_TA_QUEUE = 1,             /* queued */
  43         __BLK_TA_BACKMERGE,             /* back merged to existing rq */
  44         __BLK_TA_FRONTMERGE,            /* front merge to existing rq */
  45         __BLK_TA_GETRQ,                 /* allocated new request */
  46         __BLK_TA_SLEEPRQ,               /* sleeping on rq allocation */
  47         __BLK_TA_REQUEUE,               /* request requeued */
  48         __BLK_TA_ISSUE,                 /* sent to driver */
  49         __BLK_TA_COMPLETE,              /* completed by driver */
  50         __BLK_TA_PLUG,                  /* queue was plugged */
  51         __BLK_TA_UNPLUG_IO,             /* queue was unplugged by io */
  52         __BLK_TA_UNPLUG_TIMER,          /* queue was unplugged by timer */
  53         __BLK_TA_INSERT,                /* insert request */
  54         __BLK_TA_SPLIT,                 /* bio was split */
  55         __BLK_TA_BOUNCE,                /* bio was bounced */
  56         __BLK_TA_REMAP,                 /* bio was remapped */
  57         __BLK_TA_ABORT,                 /* request aborted */
  58         __BLK_TA_DRV_DATA,              /* driver-specific binary data */
  59 };
  60
  61 /*
  62  * Notify events.
  63  */
  64 enum blktrace_notify {
  65         __BLK_TN_PROCESS = 0,           /* establish pid/name mapping */
  66         __BLK_TN_TIMESTAMP,             /* include system clock */
  67         __BLK_TN_MESSAGE,               /* Character string message */
  68 };
  69
  70
  71 /*
  72  * Trace actions in full. Additionally, read or write is masked
  73  */
  74 #define BLK_TA_QUEUE            (__BLK_TA_QUEUE | BLK_TC_ACT(BLK_TC_QUEUE))
  75 #define BLK_TA_BACKMERGE        (__BLK_TA_BACKMERGE | BLK_TC_ACT(BLK_TC_QUEUE))
  76 #define BLK_TA_FRONTMERGE       (__BLK_TA_FRONTMERGE | BLK_TC_ACT(BLK_TC_QUEUE))
  77 #define BLK_TA_GETRQ            (__BLK_TA_GETRQ | BLK_TC_ACT(BLK_TC_QUEUE))
  78 #define BLK_TA_SLEEPRQ          (__BLK_TA_SLEEPRQ | BLK_TC_ACT(BLK_TC_QUEUE))
  79 #define BLK_TA_REQUEUE          (__BLK_TA_REQUEUE | BLK_TC_ACT(BLK_TC_REQUEUE))
  80 #define BLK_TA_ISSUE            (__BLK_TA_ISSUE | BLK_TC_ACT(BLK_TC_ISSUE))
  81 #define BLK_TA_COMPLETE         (__BLK_TA_COMPLETE| BLK_TC_ACT(BLK_TC_COMPLETE))
  82 #define BLK_TA_PLUG             (__BLK_TA_PLUG | BLK_TC_ACT(BLK_TC_QUEUE))
  83 #define BLK_TA_UNPLUG_IO        (__BLK_TA_UNPLUG_IO | BLK_TC_ACT(BLK_TC_QUEUE))
  84 #define BLK_TA_UNPLUG_TIMER     (__BLK_TA_UNPLUG_TIMER | BLK_TC_ACT(BLK_TC_QUEUE))
  85 #define BLK_TA_INSERT           (__BLK_TA_INSERT | BLK_TC_ACT(BLK_TC_QUEUE))
  86 #define BLK_TA_SPLIT            (__BLK_TA_SPLIT)
  87 #define BLK_TA_BOUNCE           (__BLK_TA_BOUNCE)
  88 #define BLK_TA_REMAP            (__BLK_TA_REMAP | BLK_TC_ACT(BLK_TC_QUEUE))
  89 #define BLK_TA_ABORT            (__BLK_TA_ABORT | BLK_TC_ACT(BLK_TC_QUEUE))
  90 #define BLK_TA_DRV_DATA (__BLK_TA_DRV_DATA | BLK_TC_ACT(BLK_TC_DRV_DATA))
  91
  92 #define BLK_TN_PROCESS          (__BLK_TN_PROCESS | BLK_TC_ACT(BLK_TC_NOTIFY))
  93 #define BLK_TN_TIMESTAMP        (__BLK_TN_TIMESTAMP | BLK_TC_ACT(BLK_TC_NOTIFY))
  94 #define BLK_TN_MESSAGE          (__BLK_TN_MESSAGE | BLK_TC_ACT(BLK_TC_NOTIFY))
  95
  96 #define BLK_IO_TRACE_MAGIC      0x65617400
  97 #define BLK_IO_TRACE_VERSION    0x07
  98
  99 /*
 100  * The trace itself
 101  */
 102 struct blk_io_trace {
 103         __u32 magic;            /* MAGIC << 8 | version */
 104         __u32 sequence;         /* event number */
 105         __u64 time;             /* in microseconds */
 106         __u64 sector;           /* disk offset */
 107         __u32 bytes;            /* transfer length */
 108         __u32 action;           /* what happened */
 109         __u32 pid;              /* who did it */
 110         __u32 device;           /* device number */
 111         __u32 cpu;              /* on what cpu did it happen */
 112         __u16 error;            /* completion error */
 113         __u16 pdu_len;          /* length of data after this trace */
 114 };
 115
 116 /*
 117  * The remap event
 118  */
 119 struct blk_io_trace_remap {
 120         __be32 device_from;
 121         __be32 device_to;
 122         __be64 sector_from;
 123 };
 124
 125 enum {
 126         Blktrace_setup = 1,
 127         Blktrace_running,
 128         Blktrace_stopped,
 129 };
 130
 131 #define BLKTRACE_BDEV_SIZE      32
 132
 133 /*
 134  * User setup structure passed with BLKTRACESTART
 135  */
 136 struct blk_user_trace_setup {
 137         char name[BLKTRACE_BDEV_SIZE];  /* output */
 138         __u16 act_mask;                 /* input */
 139         __u32 buf_size;                 /* input */
 140         __u32 buf_nr;                   /* input */
 141         __u64 start_lba;
 142         __u64 end_lba;
 143         __u32 pid;
 144 };
 145
 146 #ifdef __KERNEL__
 147 #if defined(CONFIG_BLK_DEV_IO_TRACE)
 148
 149 #include <linux/sysfs.h>
 150
 151 struct blk_trace {
 152         int trace_state;
 153         struct rchan *rchan;
 154         unsigned long __percpu *sequence;
 155         unsigned char __percpu *msg_data;
 156         u16 act_mask;
 157         u64 start_lba;
 158         u64 end_lba;
 159         u32 pid;
 160         u32 dev;
 161         struct dentry *dir;
 162         struct dentry *dropped_file;
 163         struct dentry *msg_file;
 164         atomic_t dropped;
 165 };
 166
 167 extern int blk_trace_ioctl(struct block_device *, unsigned, char __user *);
 168 extern void blk_trace_shutdown(struct request_queue *);
 169 extern int do_blk_trace_setup(struct request_queue *q, char *name,
 170                               dev_t dev, struct block_device *bdev,
 171                               struct blk_user_trace_setup *buts);
 172 extern void __trace_note_message(struct blk_trace *, const char *fmt, ...);
 173
 174 /**
 175  * blk_add_trace_msg - Add a (simple) message to the blktrace stream
 176  * @q:          queue the io is for
 177  * @fmt:        format to print message in
 178  * args...      Variable argument list for format
 179  *
 180  * Description:
 181  *     Records a (simple) message onto the blktrace stream.
 182  *
 183  *     NOTE: BLK_TN_MAX_MSG characters are output at most.
 184  *     NOTE: Can not use 'static inline' due to presence of var args...
 185  *
 186  **/
 187 #define blk_add_trace_msg(q, fmt, ...)                                  \
 188         do {                                                            \
 189                 struct blk_trace *bt = (q)->blk_trace;                  \
 190                 if (unlikely(bt))                                       \
 191                         __trace_note_message(bt, fmt, ##__VA_ARGS__);   \
 192         } while (0)
 193 #define BLK_TN_MAX_MSG          128
 194
 195 extern void blk_add_driver_data(struct request_queue *q, struct request *rq,
 196                                 void *data, size_t len);
 197 extern int blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
 198                            struct block_device *bdev,
 199                            char __user *arg);
 200 extern int blk_trace_startstop(struct request_queue *q, int start);
 201 extern int blk_trace_remove(struct request_queue *q);
 202 extern void blk_trace_remove_sysfs(struct device *dev);
 203 extern int blk_trace_init_sysfs(struct device *dev);
 204
 205 extern struct attribute_group blk_trace_attr_group;
 206
 207 #else /* !CONFIG_BLK_DEV_IO_TRACE */
 208 # define blk_trace_ioctl(bdev, cmd, arg)                (-ENOTTY)
 209 # define blk_trace_shutdown(q)                          do { } while (0)
 210 # define do_blk_trace_setup(q, name, dev, bdev, buts)   (-ENOTTY)
 211 # define blk_add_driver_data(q, rq, data, len)          do {} while (0)
 212 # define blk_trace_setup(q, name, dev, bdev, arg)       (-ENOTTY)
 213 # define blk_trace_startstop(q, start)                  (-ENOTTY)
 214 # define blk_trace_remove(q)                            (-ENOTTY)
 215 # define blk_add_trace_msg(q, fmt, ...)                 do { } while (0)
 216 # define blk_trace_remove_sysfs(dev)                    do { } while (0)
 217 static inline int blk_trace_init_sysfs(struct device *dev)
 218 {
 219         return 0;
 220 }
 221
 222 #endif /* CONFIG_BLK_DEV_IO_TRACE */
 223
 224 #ifdef CONFIG_COMPAT
 225
 226 struct compat_blk_user_trace_setup {
 227         char name[32];
 228         u16 act_mask;
 229         u32 buf_size;
 230         u32 buf_nr;
 231         compat_u64 start_lba;
 232         compat_u64 end_lba;
 233         u32 pid;
 234 };
 235 #define BLKTRACESETUP32 _IOWR(0x12, 115, struct compat_blk_user_trace_setup)
 236
 237 #endif
 238
 239 #if defined(CONFIG_EVENT_TRACING) && defined(CONFIG_BLOCK)
 240
 241 static inline int blk_cmd_buf_len(struct request *rq)
 242 {
 243         return (rq->cmd_type == REQ_TYPE_BLOCK_PC) ? rq->cmd_len * 3 : 1;
 244 }
 245
 246 extern void blk_dump_cmd(char *buf, struct request *rq);
 247 extern void blk_fill_rwbs(char *rwbs, u32 rw, int bytes);
 248
 249 #endif /* CONFIG_EVENT_TRACING && CONFIG_BLOCK */
 250
 251 #endif /* __KERNEL__ */
 252 #endif