[PATCH v2] debugfs: add definition of debugfs_real_fops() if CONFIG_DEBUG_FS unset

[PATCH v2] debugfs: add definition of debugfs_real_fops() if CONFIG_DEBUG_FS unset

[Jakub Kicinski]

Recent commit moved the implementation of debugfs_real_fops()
out of the header file.  The declaration, however, is only
provided if CONFIG_DEBUG_FS is set.  Add an empty static inline
definition for when CONFIG_DEBUG_FS is unset.

Fixes: 7c8d469877b1 ("debugfs: add support for more elaborate ->d_fsdata")
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
---
 include/linux/debugfs.h | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/include/linux/debugfs.h b/include/linux/debugfs.h
index f36ecc2a5712..95ebbdce4193 100644
--- a/include/linux/debugfs.h
+++ b/include/linux/debugfs.h
@@ -216,6 +216,11 @@ static inline void debugfs_remove(struct dentry *dentry)
 static inline void debugfs_remove_recursive(struct dentry *dentry)
 { }
 
+static inline const struct file_operations *debugfs_real_fops(const struct file *filp)
+{
+	return NULL;
+}
+
 static inline int debugfs_file_get(struct dentry *dentry)
 {
 	return 0;
-- 
2.14.1

Re: [oss-drivers] [PATCH v2] debugfs: add definition of debugfs_real_fops() if CONFIG_DEBUG_FS unset

[Simon Horman]

On Mon, Nov 27, 2017 at 12:35:44PM -0800, Jakub Kicinski wrote:
> Recent commit moved the implementation of debugfs_real_fops()
> out of the header file.  The declaration, however, is only
> provided if CONFIG_DEBUG_FS is set.  Add an empty static inline
> definition for when CONFIG_DEBUG_FS is unset.
> 
> Fixes: 7c8d469877b1 ("debugfs: add support for more elaborate ->d_fsdata")
> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>

Reviewed-by: Simon Horman <simon.horman@netronome.com>

Re: [PATCH v2] debugfs: add definition of debugfs_real_fops() if CONFIG_DEBUG_FS unset

[Greg Kroah-Hartman]

On Mon, Nov 27, 2017 at 12:35:44PM -0800, Jakub Kicinski wrote:
> Recent commit moved the implementation of debugfs_real_fops()
> out of the header file.  The declaration, however, is only
> provided if CONFIG_DEBUG_FS is set.  Add an empty static inline
> definition for when CONFIG_DEBUG_FS is unset.
> 
> Fixes: 7c8d469877b1 ("debugfs: add support for more elaborate ->d_fsdata")
> Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
> ---
>  include/linux/debugfs.h | 5 +++++
>  1 file changed, 5 insertions(+)

Arnd sent me a better patch for this last week that I'll queue up now.

thanks,

greg k-h

Re: [PATCH v2] debugfs: add definition of debugfs_real_fops() if CONFIG_DEBUG_FS unset

[Jakub Kicinski]

On Tue, 28 Nov 2017 15:23:00 +0100, Greg Kroah-Hartman wrote:
> On Mon, Nov 27, 2017 at 12:35:44PM -0800, Jakub Kicinski wrote:
> > Recent commit moved the implementation of debugfs_real_fops()
> > out of the header file.  The declaration, however, is only
> > provided if CONFIG_DEBUG_FS is set.  Add an empty static inline
> > definition for when CONFIG_DEBUG_FS is unset.
> > 
> > Fixes: 7c8d469877b1 ("debugfs: add support for more elaborate ->d_fsdata")
> > Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
> > ---
> >  include/linux/debugfs.h | 5 +++++
> >  1 file changed, 5 insertions(+)  
> 
> Arnd sent me a better patch for this last week that I'll queue up now.

Arnd's patch assumes all call sites can be eliminated, i.e. all of the
users are static functions assigned to static fops and compiler is
clever enough.  It does solve my immediate problem but let's wait and
see if that bites us on the rear later :)