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 int do_blk_trace_setup(struct request_queue *q, char *name,
  34                               dev_t dev, struct block_device *bdev,
  35                               struct blk_user_trace_setup *buts);
  36 extern __printf(2, 3)
  37 void __trace_note_message(struct blk_trace *, const char *fmt, ...);
  38
  39 /**
  40  * blk_add_trace_msg - Add a (simple) message to the blktrace stream
  41  * @q:          queue the io is for
  42  * @fmt:        format to print message in
  43  * args...      Variable argument list for format
  44  *
  45  * Description:
  46  *     Records a (simple) message onto the blktrace stream.
  47  *
  48  *     NOTE: BLK_TN_MAX_MSG characters are output at most.
  49  *     NOTE: Can not use 'static inline' due to presence of var args...
  50  *
  51  **/
  52 #define blk_add_trace_msg(q, fmt, ...)                                  \
  53         do {                                                            \
  54                 struct blk_trace *bt = (q)->blk_trace;                  \
  55                 if (unlikely(bt))                                       \
  56                         __trace_note_message(bt, fmt, ##__VA_ARGS__);   \
  57         } while (0)
  58 #define BLK_TN_MAX_MSG          128
  59
  60 static inline bool blk_trace_note_message_enabled(struct request_queue *q)
  61 {
  62         struct blk_trace *bt = q->blk_trace;
  63         if (likely(!bt))
  64                 return false;
  65         return bt->act_mask & BLK_TC_NOTIFY;
  66 }
  67
  68 extern void blk_add_driver_data(struct request_queue *q, struct request *rq,
  69                                 void *data, size_t len);
  70 extern int blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
  71                            struct block_device *bdev,
  72                            char __user *arg);
  73 extern int blk_trace_startstop(struct request_queue *q, int start);
  74 extern int blk_trace_remove(struct request_queue *q);
  75 extern void blk_trace_remove_sysfs(struct device *dev);
  76 extern int blk_trace_init_sysfs(struct device *dev);
  77
  78 extern struct attribute_group blk_trace_attr_group;
  79
  80 #else /* !CONFIG_BLK_DEV_IO_TRACE */
  81 # define blk_trace_ioctl(bdev, cmd, arg)                (-ENOTTY)
  82 # define blk_trace_shutdown(q)                          do { } while (0)
  83 # define do_blk_trace_setup(q, name, dev, bdev, buts)   (-ENOTTY)
  84 # define blk_add_driver_data(q, rq, data, len)          do {} while (0)
  85 # define blk_trace_setup(q, name, dev, bdev, arg)       (-ENOTTY)
  86 # define blk_trace_startstop(q, start)                  (-ENOTTY)
  87 # define blk_trace_remove(q)                            (-ENOTTY)
  88 # define blk_add_trace_msg(q, fmt, ...)                 do { } while (0)
  89 # define blk_trace_remove_sysfs(dev)                    do { } while (0)
  90 # define blk_trace_note_message_enabled(q)              (false)
  91 static inline int blk_trace_init_sysfs(struct device *dev)
  92 {
  93         return 0;
  94 }
  95
  96 #endif /* CONFIG_BLK_DEV_IO_TRACE */
  97
  98 #ifdef CONFIG_COMPAT
  99
 100 struct compat_blk_user_trace_setup {
 101         char name[BLKTRACE_BDEV_SIZE];
 102         u16 act_mask;
 103         u32 buf_size;
 104         u32 buf_nr;
 105         compat_u64 start_lba;
 106         compat_u64 end_lba;
 107         u32 pid;
 108 };
 109 #define BLKTRACESETUP32 _IOWR(0x12, 115, struct compat_blk_user_trace_setup)
 110
 111 #endif
 112
 113 #if defined(CONFIG_EVENT_TRACING) && defined(CONFIG_BLOCK)
 114
 115 static inline int blk_cmd_buf_len(struct request *rq)
 116 {
 117         return (rq->cmd_type == REQ_TYPE_BLOCK_PC) ? rq->cmd_len * 3 : 1;
 118 }
 119
 120 extern void blk_dump_cmd(char *buf, struct request *rq);
 121 extern void blk_fill_rwbs(char *rwbs, u32 rw, int bytes);
 122
 123 #endif /* CONFIG_EVENT_TRACING && CONFIG_BLOCK */
 124
 125 #endif