diff options
Diffstat (limited to 'Documentation/filesystems/debugfs.txt')
| -rw-r--r-- | Documentation/filesystems/debugfs.txt | 50 |
1 files changed, 29 insertions, 21 deletions
diff --git a/Documentation/filesystems/debugfs.txt b/Documentation/filesystems/debugfs.txt index 9e27c843d00e..dc497b96fa4f 100644 --- a/Documentation/filesystems/debugfs.txt +++ b/Documentation/filesystems/debugfs.txt @@ -68,41 +68,49 @@ actually necessary; the debugfs code provides a number of helper functions for simple situations. Files containing a single integer value can be created with any of: - struct dentry *debugfs_create_u8(const char *name, umode_t mode, - struct dentry *parent, u8 *value); - struct dentry *debugfs_create_u16(const char *name, umode_t mode, - struct dentry *parent, u16 *value); + void debugfs_create_u8(const char *name, umode_t mode, + struct dentry *parent, u8 *value); + void debugfs_create_u16(const char *name, umode_t mode, + struct dentry *parent, u16 *value); struct dentry *debugfs_create_u32(const char *name, umode_t mode, struct dentry *parent, u32 *value); - struct dentry *debugfs_create_u64(const char *name, umode_t mode, - struct dentry *parent, u64 *value); + void debugfs_create_u64(const char *name, umode_t mode, + struct dentry *parent, u64 *value); These files support both reading and writing the given value; if a specific file should not be written to, simply set the mode bits accordingly. The values in these files are in decimal; if hexadecimal is more appropriate, the following functions can be used instead: - struct dentry *debugfs_create_x8(const char *name, umode_t mode, - struct dentry *parent, u8 *value); - struct dentry *debugfs_create_x16(const char *name, umode_t mode, - struct dentry *parent, u16 *value); - struct dentry *debugfs_create_x32(const char *name, umode_t mode, - struct dentry *parent, u32 *value); - struct dentry *debugfs_create_x64(const char *name, umode_t mode, - struct dentry *parent, u64 *value); + void debugfs_create_x8(const char *name, umode_t mode, + struct dentry *parent, u8 *value); + void debugfs_create_x16(const char *name, umode_t mode, + struct dentry *parent, u16 *value); + void debugfs_create_x32(const char *name, umode_t mode, + struct dentry *parent, u32 *value); + void debugfs_create_x64(const char *name, umode_t mode, + struct dentry *parent, u64 *value); These functions are useful as long as the developer knows the size of the value to be exported. Some types can have different widths on different -architectures, though, complicating the situation somewhat. There is a -function meant to help out in one special case: +architectures, though, complicating the situation somewhat. There are +functions meant to help out in such special cases: - struct dentry *debugfs_create_size_t(const char *name, umode_t mode, - struct dentry *parent, - size_t *value); + void debugfs_create_size_t(const char *name, umode_t mode, + struct dentry *parent, size_t *value); As might be expected, this function will create a debugfs file to represent a variable of type size_t. +Similarly, there are helpers for variables of type unsigned long, in decimal +and hexadecimal: + + struct dentry *debugfs_create_ulong(const char *name, umode_t mode, + struct dentry *parent, + unsigned long *value); + void debugfs_create_xul(const char *name, umode_t mode, + struct dentry *parent, unsigned long *value); + Boolean values can be placed in debugfs with: struct dentry *debugfs_create_bool(const char *name, umode_t mode, @@ -114,8 +122,8 @@ lower-case values, or 1 or 0. Any other input will be silently ignored. Also, atomic_t values can be placed in debugfs with: - struct dentry *debugfs_create_atomic_t(const char *name, umode_t mode, - struct dentry *parent, atomic_t *value) + void debugfs_create_atomic_t(const char *name, umode_t mode, + struct dentry *parent, atomic_t *value) A read of this file will get atomic_t values, and a write of this file will set atomic_t values. |