diff options
Diffstat (limited to 'include/linux/debugfs.h')
| -rw-r--r-- | include/linux/debugfs.h | 118 |
1 files changed, 106 insertions, 12 deletions
diff --git a/include/linux/debugfs.h b/include/linux/debugfs.h index ea2d919fd9c7..7cecda29447e 100644 --- a/include/linux/debugfs.h +++ b/include/linux/debugfs.h @@ -57,7 +57,6 @@ static const struct file_operations __fops = { \ .release = simple_attr_release, \ .read = debugfs_attr_read, \ .write = (__is_signed) ? debugfs_attr_write_signed : debugfs_attr_write, \ - .llseek = no_llseek, \ } #define DEFINE_DEBUGFS_ATTRIBUTE(__fops, __get, __set, __fmt) \ @@ -68,13 +67,77 @@ static const struct file_operations __fops = { \ typedef struct vfsmount *(*debugfs_automount_t)(struct dentry *, void *); +struct debugfs_short_fops { + ssize_t (*read)(struct file *, char __user *, size_t, loff_t *); + ssize_t (*write)(struct file *, const char __user *, size_t, loff_t *); + loff_t (*llseek) (struct file *, loff_t, int); +}; + #if defined(CONFIG_DEBUG_FS) struct dentry *debugfs_lookup(const char *name, struct dentry *parent); -struct dentry *debugfs_create_file(const char *name, umode_t mode, - struct dentry *parent, void *data, - const struct file_operations *fops); +struct dentry *debugfs_create_file_full(const char *name, umode_t mode, + struct dentry *parent, void *data, + const void *aux, + const struct file_operations *fops); +struct dentry *debugfs_create_file_short(const char *name, umode_t mode, + struct dentry *parent, void *data, + const void *aux, + const struct debugfs_short_fops *fops); + +/** + * debugfs_create_file - create a file in the debugfs filesystem + * @name: a pointer to a string containing the name of the file to create. + * @mode: the permission that the file should have. + * @parent: a pointer to the parent dentry for this file. This should be a + * directory dentry if set. If this parameter is NULL, then the + * file will be created in the root of the debugfs filesystem. + * @data: a pointer to something that the caller will want to get to later + * on. The inode.i_private pointer will point to this value on + * the open() call. + * @fops: a pointer to a struct file_operations or struct debugfs_short_fops that + * should be used for this file. + * + * This is the basic "create a file" function for debugfs. It allows for a + * wide range of flexibility in creating a file, or a directory (if you want + * to create a directory, the debugfs_create_dir() function is + * recommended to be used instead.) + * + * This function will return a pointer to a dentry if it succeeds. This + * pointer must be passed to the debugfs_remove() function when the file is + * to be removed (no automatic cleanup happens if your module is unloaded, + * you are responsible here.) If an error occurs, ERR_PTR(-ERROR) will be + * returned. + * + * If debugfs is not enabled in the kernel, the value -%ENODEV will be + * returned. + * + * If fops points to a struct debugfs_short_fops, then simple_open() will be + * used for the open, and only read/write/llseek are supported and are proxied, + * so no module reference or release are needed. + * + * NOTE: it's expected that most callers should _ignore_ the errors returned + * by this function. Other debugfs functions handle the fact that the "dentry" + * passed to them could be an error and they don't crash in that case. + * Drivers should generally work fine even if debugfs fails to init anyway. + */ +#define debugfs_create_file(name, mode, parent, data, fops) \ + _Generic(fops, \ + const struct file_operations *: debugfs_create_file_full, \ + const struct debugfs_short_fops *: debugfs_create_file_short, \ + struct file_operations *: debugfs_create_file_full, \ + struct debugfs_short_fops *: debugfs_create_file_short) \ + (name, mode, parent, data, NULL, fops) + +#define debugfs_create_file_aux(name, mode, parent, data, aux, fops) \ + _Generic(fops, \ + const struct file_operations *: debugfs_create_file_full, \ + const struct debugfs_short_fops *: debugfs_create_file_short, \ + struct file_operations *: debugfs_create_file_full, \ + struct debugfs_short_fops *: debugfs_create_file_short) \ + (name, mode, parent, data, aux, fops) + struct dentry *debugfs_create_file_unsafe(const char *name, umode_t mode, struct dentry *parent, void *data, const struct file_operations *fops); @@ -99,7 +162,7 @@ void debugfs_remove(struct dentry *dentry); void debugfs_lookup_and_remove(const char *name, struct dentry *parent); -const struct file_operations *debugfs_real_fops(const struct file *filp); +void *debugfs_get_aux(const struct file *file); int debugfs_file_get(struct dentry *dentry); void debugfs_file_put(struct dentry *dentry); @@ -111,8 +174,7 @@ ssize_t debugfs_attr_write(struct file *file, const char __user *buf, ssize_t debugfs_attr_write_signed(struct file *file, const char __user *buf, size_t len, loff_t *ppos); -struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry, - struct dentry *new_dir, const char *new_name); +int debugfs_change_name(struct dentry *dentry, const char *fmt, ...) __printf(2, 3); void debugfs_create_u8(const char *name, umode_t mode, struct dentry *parent, u8 *value); @@ -171,6 +233,25 @@ ssize_t debugfs_write_file_bool(struct file *file, const char __user *user_buf, ssize_t debugfs_read_file_str(struct file *file, char __user *user_buf, size_t count, loff_t *ppos); +/** + * struct debugfs_cancellation - cancellation data + * @list: internal, for keeping track + * @cancel: callback to call + * @cancel_data: extra data for the callback to call + */ +struct debugfs_cancellation { + struct list_head list; + void (*cancel)(struct dentry *, void *); + void *cancel_data; +}; + +void __acquires(cancellation) +debugfs_enter_cancellation(struct file *file, + struct debugfs_cancellation *cancellation); +void __releases(cancellation) +debugfs_leave_cancellation(struct file *file, + struct debugfs_cancellation *cancellation); + #else #include <linux/err.h> @@ -187,9 +268,17 @@ static inline struct dentry *debugfs_lookup(const char *name, return ERR_PTR(-ENODEV); } +static inline struct dentry *debugfs_create_file_aux(const char *name, + umode_t mode, struct dentry *parent, + void *data, void *aux, + const void *fops) +{ + return ERR_PTR(-ENODEV); +} + static inline struct dentry *debugfs_create_file(const char *name, umode_t mode, struct dentry *parent, void *data, - const struct file_operations *fops) + const void *fops) { return ERR_PTR(-ENODEV); } @@ -239,7 +328,7 @@ static inline void debugfs_lookup_and_remove(const char *name, struct dentry *parent) { } -const struct file_operations *debugfs_real_fops(const struct file *filp); +void *debugfs_get_aux(const struct file *file); static inline int debugfs_file_get(struct dentry *dentry) { @@ -269,10 +358,10 @@ static inline ssize_t debugfs_attr_write_signed(struct file *file, return -ENODEV; } -static inline struct dentry *debugfs_rename(struct dentry *old_dir, struct dentry *old_dentry, - struct dentry *new_dir, char *new_name) +static inline int __printf(2, 3) debugfs_change_name(struct dentry *dentry, + const char *fmt, ...) { - return ERR_PTR(-ENODEV); + return -ENODEV; } static inline void debugfs_create_u8(const char *name, umode_t mode, @@ -380,6 +469,11 @@ static inline ssize_t debugfs_read_file_str(struct file *file, #endif +#define debugfs_create_file_aux_num(name, mode, parent, data, n, fops) \ + debugfs_create_file_aux(name, mode, parent, data, \ + (void *)(unsigned long)n, fops) +#define debugfs_get_aux_num(f) (unsigned long)debugfs_get_aux(f) + /** * debugfs_create_xul - create a debugfs file that is used to read and write an * unsigned long value, formatted in hexadecimal |