include/linux/blktrace_api.h

   1 #ifndef BLKTRACE_H
   2 #define BLKTRACE_H
   3
   4 #include <linux/blkdev.h>
   5 #include <linux/relay.h>
   6 #include <linux/compat.h>
   7 #include <uapi/linux/blktrace_api.h>
   8 #include <linux/list.h>
   9
  10 #if defined(CONFIG_BLK_DEV_IO_TRACE)
  11
  12 #include <linux/sysfs.h>
  13
  14 struct blk_trace {
  15         int trace_state;
  16         struct rchan *rchan;
  17         unsigned long __percpu *sequence;
  18         unsigned char __percpu *msg_data;
  19         u16 act_mask;
  20         u64 start_lba;
  21         u64 end_lba;
  22         u32 pid;
  23         u32 dev;
  24         struct dentry *dir;
  25         struct dentry *dropped_file;
  26         struct dentry *msg_file;
  27         struct list_head running_list;
  28         atomic_t dropped;
  29 };
  30
  31 extern int blk_trace_ioctl(struct block_device *, unsigned, char __user *);
  32 extern void blk_trace_shutdown(struct request_queue *);
  33 extern __printf(2, 3)
  34 void __trace_note_message(struct blk_trace *, const char *fmt, ...);
  35
  36 /**
  37  * blk_add_trace_msg - Add a (simple) message to the blktrace stream
  38  * @q:          queue the io is for
  39  * @fmt:        format to print message in
  40  * args...      Variable argument list for format
  41  *
  42  * Description:
  43  *     Records a (simple) message onto the blktrace stream.
  44  *
  45  *     NOTE: BLK_TN_MAX_MSG characters are output at most.
  46  *     NOTE: Can not use 'static inline' due to presence of var args...
  47  *
  48  **/
  49 #define blk_add_trace_msg(q, fmt, ...)                                  \
  50         do {                                                            \
  51                 struct blk_trace *bt = (q)->blk_trace;                  \
  52                 if (unlikely(bt))                                       \
  53                         __trace_note_message(bt, fmt, ##__VA_ARGS__);   \
  54         } while (0)
  55 #define BLK_TN_MAX_MSG          128
  56
  57 static inline bool blk_trace_note_message_enabled(struct request_queue *q)
  58 {
  59         struct blk_trace *bt = q->blk_trace;
  60         if (likely(!bt))
  61                 return false;
  62         return bt->act_mask & BLK_TC_NOTIFY;
  63 }
  64
  65 extern void blk_add_driver_data(struct request_queue *q, struct request *rq,
  66                                 void *data, size_t len);
  67 extern int blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
  68                            struct block_device *bdev,
  69                            char __user *arg);
  70 extern int blk_trace_startstop(struct request_queue *q, int start);
  71 extern int blk_trace_remove(struct request_queue *q);
  72 extern void blk_trace_remove_sysfs(struct device *dev);
  73 extern int blk_trace_init_sysfs(struct device *dev);
  74
  75 extern struct attribute_group blk_trace_attr_group;
  76
  77 #else /* !CONFIG_BLK_DEV_IO_TRACE */
  78 # define blk_trace_ioctl(bdev, cmd, arg)                (-ENOTTY)
  79 # define blk_trace_shutdown(q)                          do { } while (0)
  80 # define blk_add_driver_data(q, rq, data, len)          do {} while (0)
  81 # define blk_trace_setup(q, name, dev, bdev, arg)       (-ENOTTY)
  82 # define blk_trace_startstop(q, start)                  (-ENOTTY)
  83 # define blk_trace_remove(q)                            (-ENOTTY)
  84 # define blk_add_trace_msg(q, fmt, ...)                 do { } while (0)
  85 # define blk_trace_remove_sysfs(dev)                    do { } while (0)
  86 # define blk_trace_note_message_enabled(q)              (false)
  87 static inline int blk_trace_init_sysfs(struct device *dev)
  88 {
  89         return 0;
  90 }
  91
  92 #endif /* CONFIG_BLK_DEV_IO_TRACE */
  93
  94 #ifdef CONFIG_COMPAT
  95
  96 struct compat_blk_user_trace_setup {
  97         char name[BLKTRACE_BDEV_SIZE];
  98         u16 act_mask;
  99         u32 buf_size;
 100         u32 buf_nr;
 101         compat_u64 start_lba;
 102         compat_u64 end_lba;
 103         u32 pid;
 104 };
 105 #define BLKTRACESETUP32 _IOWR(0x12, 115, struct compat_blk_user_trace_setup)
 106
 107 #endif
 108
 109 extern void blk_fill_rwbs(char *rwbs, unsigned int op, int bytes);
 110
 111 static inline sector_t blk_rq_trace_sector(struct request *rq)
 112 {
 113         return blk_rq_is_passthrough(rq) ? 0 : blk_rq_pos(rq);
 114 }
 115
 116 static inline unsigned int blk_rq_trace_nr_sectors(struct request *rq)
 117 {
 118         return blk_rq_is_passthrough(rq) ? 0 : blk_rq_sectors(rq);
 119 }
 120
 121 #endif