root/include/linux/blktrace_api.h

INCLUDED FROM

DEFINITIONS

1. __printf
2. blk_trace_init_sysfs
3. blk_cmd_buf_len

#ifndef BLKTRACE_H
#define BLKTRACE_H

#include <linux/blkdev.h>
#include <linux/relay.h>
#include <linux/compat.h>
#include <uapi/linux/blktrace_api.h>
#include <linux/list.h>

#if defined(CONFIG_BLK_DEV_IO_TRACE)

#include <linux/sysfs.h>

struct blk_trace {
        int trace_state;
        struct rchan *rchan;
        unsigned long __percpu *sequence;
        unsigned char __percpu *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;
        struct list_head running_list;
        atomic_t dropped;
};

extern int blk_trace_ioctl(struct block_device *, unsigned, char __user *);
extern void blk_trace_shutdown(struct request_queue *);
extern int do_blk_trace_setup(struct request_queue *q, char *name,
                              dev_t dev, struct block_device *bdev,
                              struct blk_user_trace_setup *buts);
extern __printf(2, 3)
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

extern void blk_add_driver_data(struct request_queue *q, struct request *rq,
                                void *data, size_t len);
extern int blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
                           struct block_device *bdev,
                           char __user *arg);
extern int blk_trace_startstop(struct request_queue *q, int start);
extern int blk_trace_remove(struct request_queue *q);
extern void blk_trace_remove_sysfs(struct device *dev);
extern int blk_trace_init_sysfs(struct device *dev);

extern struct attribute_group blk_trace_attr_group;

#else /* !CONFIG_BLK_DEV_IO_TRACE */
# define blk_trace_ioctl(bdev, cmd, arg)                (-ENOTTY)
# define blk_trace_shutdown(q)                          do { } while (0)
# define do_blk_trace_setup(q, name, dev, bdev, buts)   (-ENOTTY)
# define blk_add_driver_data(q, rq, data, len)          do {} while (0)
# define blk_trace_setup(q, name, dev, bdev, 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)
# define blk_trace_remove_sysfs(dev)                    do { } while (0)
static inline int blk_trace_init_sysfs(struct device *dev)
{
        return 0;
}

#endif /* CONFIG_BLK_DEV_IO_TRACE */

#ifdef CONFIG_COMPAT

struct compat_blk_user_trace_setup {
        char name[BLKTRACE_BDEV_SIZE];
        u16 act_mask;
        u32 buf_size;
        u32 buf_nr;
        compat_u64 start_lba;
        compat_u64 end_lba;
        u32 pid;
};
#define BLKTRACESETUP32 _IOWR(0x12, 115, struct compat_blk_user_trace_setup)

#endif

#if defined(CONFIG_EVENT_TRACING) && defined(CONFIG_BLOCK)

static inline int blk_cmd_buf_len(struct request *rq)
{
        return (rq->cmd_type == REQ_TYPE_BLOCK_PC) ? rq->cmd_len * 3 : 1;
}

extern void blk_dump_cmd(char *buf, struct request *rq);
extern void blk_fill_rwbs(char *rwbs, u32 rw, int bytes);

#endif /* CONFIG_EVENT_TRACING && CONFIG_BLOCK */

#endif