#ifndef _LINUX_MMIOTRACE_H
  #define _LINUX_MMIOTRACE_H

  #include <linux/types.h>

  #include <linux/list.h>
  
  struct kmmio_probe;
  struct pt_regs;
  
  typedef void (*kmmio_pre_handler_t)(struct kmmio_probe *,
  				struct pt_regs *, unsigned long addr);
  typedef void (*kmmio_post_handler_t)(struct kmmio_probe *,
  				unsigned long condition, struct pt_regs *);
  
  struct kmmio_probe {

  	/* kmmio internal list: */
  	struct list_head	list;
  	/* start location of the probe point: */
  	unsigned long		addr;
  	/* length of the probe region: */
  	unsigned long		len;
  	/* Called before addr is executed: */
  	kmmio_pre_handler_t	pre_handler;
  	/* Called after addr is executed: */
  	kmmio_post_handler_t	post_handler;
  	void			*private;

  };

  extern unsigned int kmmio_count;
  
  extern int register_kmmio_probe(struct kmmio_probe *p);
  extern void unregister_kmmio_probe(struct kmmio_probe *p);

  extern int kmmio_init(void);
  extern void kmmio_cleanup(void);

  
  #ifdef CONFIG_MMIOTRACE

  /* kmmio is active by some kmmio_probes? */
  static inline int is_kmmio_active(void)
  {

  	return kmmio_count;
  }

  /* Called from page fault handler. */
  extern int kmmio_handler(struct pt_regs *regs, unsigned long addr);

  /* Called from ioremap.c */

  extern void mmiotrace_ioremap(resource_size_t offset, unsigned long size,
  							void __iomem *addr);

  extern void mmiotrace_iounmap(volatile void __iomem *addr);

  
  /* For anyone to insert markers. Remember trailing newline. */
  extern int mmiotrace_printk(const char *fmt, ...)
  				__attribute__ ((format (printf, 1, 2)));

  #else /* !CONFIG_MMIOTRACE: */
  static inline int is_kmmio_active(void)
  {
  	return 0;
  }
  
  static inline int kmmio_handler(struct pt_regs *regs, unsigned long addr)
  {
  	return 0;
  }

  static inline void mmiotrace_ioremap(resource_size_t offset,
  					unsigned long size, void __iomem *addr)

  {
  }

  static inline void mmiotrace_iounmap(volatile void __iomem *addr)
  {
  }

  
  static inline int mmiotrace_printk(const char *fmt, ...)
  				__attribute__ ((format (printf, 1, 0)));
  
  static inline int mmiotrace_printk(const char *fmt, ...)
  {
  	return 0;
  }
  #endif /* CONFIG_MMIOTRACE */

  enum mm_io_opcode {

  	MMIO_READ	= 0x1,	/* struct mmiotrace_rw */
  	MMIO_WRITE	= 0x2,	/* struct mmiotrace_rw */
  	MMIO_PROBE	= 0x3,	/* struct mmiotrace_map */
  	MMIO_UNPROBE	= 0x4,	/* struct mmiotrace_map */
  	MMIO_UNKNOWN_OP = 0x5,	/* struct mmiotrace_rw */

  };

  struct mmiotrace_rw {

  	resource_size_t	phys;	/* PCI address of register */
  	unsigned long	value;
  	unsigned long	pc;	/* optional program counter */
  	int		map_id;
  	unsigned char	opcode;	/* one of MMIO_{READ,WRITE,UNKNOWN_OP} */
  	unsigned char	width;	/* size of register access in bytes */

  };

  struct mmiotrace_map {

  	resource_size_t	phys;	/* base address in PCI space */
  	unsigned long	virt;	/* base virtual address */
  	unsigned long	len;	/* mapping size */
  	int		map_id;
  	unsigned char	opcode;	/* MMIO_PROBE or MMIO_UNPROBE */

  };

  /* in kernel/trace/trace_mmiotrace.c */
  extern void enable_mmiotrace(void);
  extern void disable_mmiotrace(void);
  extern void mmio_trace_rw(struct mmiotrace_rw *rw);
  extern void mmio_trace_mapping(struct mmiotrace_map *map);

  extern int mmio_trace_printk(const char *fmt, va_list args);

  #endif /* _LINUX_MMIOTRACE_H */