diff options
| author | Christian Lamparter <chunkeey@googlemail.com> | 2016-09-17 22:43:01 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2016-09-21 13:13:31 +0300 |
| commit | 86f0e06767dda7863d6d2a8f0b3b857e6ea876a0 (patch) | |
| tree | 0bba8aec84b2143fa932cc40e4ea8738d859463a /include/linux/debugfs.h | |
| parent | 2f5bb02ff22414ce156cacb163dd594b017af357 (diff) | |
| download | linux-86f0e06767dda7863d6d2a8f0b3b857e6ea876a0.tar.xz | |
debugfs: introduce a public file_operations accessor
This patch introduces an accessor which can be used
by the users of debugfs (drivers, fs, ...) to get the
original file_operations struct. It also removes the
REAL_FOPS_DEREF macro in file.c and converts the code
to use the public version.
Previously, REAL_FOPS_DEREF was only available within
the file.c of debugfs. But having a public getter
available for debugfs users is important as some
drivers (carl9170 and b43) use the pointer of the
original file_operations in conjunction with container_of()
within their debugfs implementations.
Reviewed-by: Nicolai Stange <nicstange@gmail.com>
Signed-off-by: Christian Lamparter <chunkeey@gmail.com>
Cc: stable <stable@vger.kernel.org> # 4.7+
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include/linux/debugfs.h')
| -rw-r--r-- | include/linux/debugfs.h | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/include/linux/debugfs.h b/include/linux/debugfs.h index 1438e2322d5c..4d3f0d1aec73 100644 --- a/include/linux/debugfs.h +++ b/include/linux/debugfs.h @@ -45,6 +45,23 @@ extern struct dentry *arch_debugfs_dir; extern struct srcu_struct debugfs_srcu; +/** + * debugfs_real_fops - getter for the real file operation + * @filp: a pointer to a struct file + * + * Must only be called under the protection established by + * debugfs_use_file_start(). + */ +static inline const struct file_operations *debugfs_real_fops(struct file *filp) + __must_hold(&debugfs_srcu) +{ + /* + * Neither the pointer to the struct file_operations, nor its + * contents ever change -- srcu_dereference() is not needed here. + */ + return filp->f_path.dentry->d_fsdata; +} + #if defined(CONFIG_DEBUG_FS) struct dentry *debugfs_create_file(const char *name, umode_t mode, |