Ocfs2 devel - Apr 2020 - [PATCH 6/8] simplefs: add file creation functions

On 4/14/20 2:56 PM, Greg Kroah-Hartman wrote:
> On Tue, Apr 14, 2020 at 02:43:00PM +0200, Emanuele Giuseppe Esposito wrote:
>> A bunch of code is duplicated between debugfs and tracefs, unify it to
the
>> simplefs library.
>>
>> The code is very similar, except that dentry and inode creation are
unified
>> into a single function (unlike start_creating in debugfs and tracefs,
which
>> only takes care of dentries).  This adds an output parameter to the
creation
>> functions, but pushes all error recovery into fs/simplefs.c.
>>
>> Signed-off-by: Emanuele Giuseppe Esposito <eesposit at
redhat.com>
>> ---
>>   fs/simplefs.c            | 150
+++++++++++++++++++++++++++++++++++++++
>>   include/linux/simplefs.h |  19 +++++
>>   2 files changed, 169 insertions(+)
> 
> What's wrong with libfs, isn't that supposed to be for these types
of
> "common" filesystem interactions?
> 
> Why create a whole "new" fs for this?
I assume you meant a new file. These new functions are used only by a 
few filesystems, and I didn't want to include them in vmlinux 
unconditionally, so I introduced simplefs.c and CONFIG_SIMPLEFS instead 
of extending libfs.c. In this way only fs that need this code like 
debugfs and tracefs will load it.

Thank you,

Emanuele

On Mon, Apr 20, 2020 at 03:57:48PM +0200, Emanuele Giuseppe Esposito
wrote:
> 
> 
> On 4/14/20 2:56 PM, Greg Kroah-Hartman wrote:
> > On Tue, Apr 14, 2020 at 02:43:00PM +0200, Emanuele Giuseppe Esposito
wrote:
> > > A bunch of code is duplicated between debugfs and tracefs, unify
it to the
> > > simplefs library.
> > > 
> > > The code is very similar, except that dentry and inode creation
are unified
> > > into a single function (unlike start_creating in debugfs and
tracefs, which
> > > only takes care of dentries).  This adds an output parameter to
the creation
> > > functions, but pushes all error recovery into fs/simplefs.c.
> > > 
> > > Signed-off-by: Emanuele Giuseppe Esposito <eesposit at
redhat.com>
> > > ---
> > >   fs/simplefs.c            | 150
+++++++++++++++++++++++++++++++++++++++
> > >   include/linux/simplefs.h |  19 +++++
> > >   2 files changed, 169 insertions(+)
> > 
> > What's wrong with libfs, isn't that supposed to be for these
types of
> > "common" filesystem interactions?
> > 
> > Why create a whole "new" fs for this?
> 
> I assume you meant a new file. These new functions are used only by a few
> filesystems, and I didn't want to include them in vmlinux
unconditionally,
> so I introduced simplefs.c and CONFIG_SIMPLEFS instead of extending
libfs.c.
> In this way only fs that need this code like debugfs and tracefs will load
> it.
Nothing "loads it", why not just make these libfs functions instead? 
As
the difference between the two is not obvious at all, please don't make
things confusing.

thanks,

greg k-h