LXR linux/include/linux/blktrace

   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
  14struct 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
  31extern int blk_trace_ioctl(struct block_device *, unsigned, char __user *);
  32extern void blk_trace_shutdown(struct request_queue *);
  33extern 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);
  36extern __printf(2, 3)
  37void __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
  60static 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
  68extern void blk_add_driver_data(struct request_queue *q, struct request *rq,
  69                                void *data, size_t len);
  70extern int blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
  71                           struct block_device *bdev,
  72                           char __user *arg);
  73extern int blk_trace_startstop(struct request_queue *q, int start);
  74extern int blk_trace_remove(struct request_queue *q);
  75extern void blk_trace_remove_sysfs(struct device *dev);
  76extern int blk_trace_init_sysfs(struct device *dev);
  77
  78extern 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)
  91static 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
 100struct 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
 115static 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
 120extern void blk_dump_cmd(char *buf, struct request *rq);
 121extern void blk_fill_rwbs(char *rwbs, int op, u32 rw, int bytes);
 122
 123#endif /* CONFIG_EVENT_TRACING && CONFIG_BLOCK */
 124
 125#endif
 126