debugfs_compat.h

ocfs1.2.7 源码

/* Ripped from include/linux/fs.h in the 2.6.14 kernel. */

#ifndef _DEBUGFS_COMPAT_H
#define _DEBUGFS_COMPAT_H

/*
 * simple attribute files
 *
 * These attributes behave similar to those in sysfs:
 *
 * Writing to an attribute immediately sets a value, an open file can be
 * written to multiple times.
 *
 * Reading from an attribute creates a buffer from the value that might get
 * read with multiple read calls. When the attribute has been read
 * completely, no further read calls are possible until the file is opened
 * again.
 *
 * All attributes contain a text representation of a numeric value
 * that are accessed with the get() and set() functions.
 */
#define DEFINE_SIMPLE_ATTRIBUTE(__fops, __get, __set, __fmt)		\
static int __fops ## _open(struct inode *inode, struct file *file)	\
{									\
	__simple_attr_check_format(__fmt, 0ull);			\
	return simple_attr_open(inode, file, __get, __set, __fmt);	\
}									\
static struct file_operations __fops = {				\
	.owner	 = THIS_MODULE,						\
	.open	 = __fops ## _open,					\
	.release = simple_attr_close,					\
	.read	 = simple_attr_read,					\
	.write	 = simple_attr_write,					\
};

static inline void __attribute__((format(printf, 1, 2)))
__simple_attr_check_format(const char *fmt, ...)
{
	/* don't do anything, just let the compiler check the arguments; */
}

int simple_attr_open(struct inode *inode, struct file *file,
		     u64 (*get)(void *), void (*set)(void *, u64),
		     const char *fmt);
int simple_attr_close(struct inode *inode, struct file *file);
ssize_t simple_attr_read(struct file *file, char __user *buf,
			 size_t len, loff_t *ppos);
ssize_t simple_attr_write(struct file *file, const char __user *buf,
			  size_t len, loff_t *ppos);

ssize_t compat_simple_read_from_buffer(void __user *to, size_t count,
				       loff_t *ppos, const void *from,
				       size_t available);

#endif /* _DEBUGFS_COMPAT_H */