On Thu, 2018-05-31 at 17:13 -0700, Andrew Morton wrote: > On Wed, 30 May 2018 17:18:55 +0800 Ian Kent <[email protected]> wrote: > > > > I actually had an alternative approach that I tried out successfully > > > but discarded as being too different from the original code. Just for > > > reference, this one would work as well, and allow both to be > > > compiled together. The version you posted is probably better. > > > > It's an attractive option but the problem is both implement the > > autofs file system. > > > > I've always thought you can't register the same file system at the > > same time from two distinct sources. > > > > If you're careful and compile each only as a module you could do it. > > > > But many configurations have autofs compiled built-in because of the > > auto-loading problems that arose back when there was an autofs fs > > module as well as an autofs fs module present in the autofs4 directory. > > > > Maybe it would actually work with one winning over the other but > > I'd prefer not to go that way. > > > > It will be gone in two subsequent releases if it gets merged and no > > changes to the retained code will be needed with this approach. > > I'm losing the plot here. Can you please confirm that this is the > patch we want?
Understandable. This wasn't quite what I did and at the risk of confusing matters further I'll try and explain what I did and why. I folded the change into the patch which created fs/autofs/Kconfig (autofs-create-autofs-kconfig-and-makefile.patch). However doing what you're doing here should have the same effect as long as Kbuild is smart enough to work out that "depends on AUTOFS_FS = n" doesn't apply when fs/autofs/Kconfig hasn't yet been created (by autofs-create-autofs-kconfig-and-makefile.patch). The problem is that AUTOFS_FS=y might be still be present in .config (surviving after many years) causing the bisection problem. That's why I thought it best to add the depends in fs/autofs4/Kconfig at the time fs/autofs/Kconfig is created rather than before that in autofs-update-fs-autofs4-makefile.patch, as is done here. Let me check if Kbuild will do the right thing and get back to you. > > > From: Ian Kent <[email protected]> > Subject: autofs: update fs/autofs4/Kconfig > > Update Kconfig and add a depricated warning. > > [[email protected]: make autofs4 Kconfig depend on AUTOFS_FS] > Link: http://lkml.kernel.org/r/152687649097.8263.7046086367407522029.stgit@p > luto.themaw.net > Link: http://lkml.kernel.org/r/152626706133.28589.11994171621899212952.stgit@p > luto.themaw.net > Signed-off-by: Ian Kent <[email protected]> > Tested-by: Randy Dunlap <[email protected]> > Cc: Al Viro <[email protected]> > Cc: Arnd Bergmann <[email protected]> > Signed-off-by: Andrew Morton <[email protected]> > --- > > fs/autofs4/Kconfig | 42 +++++++++++++++++++++++++++++++----------- > 1 file changed, 31 insertions(+), 11 deletions(-) > > diff -puN fs/autofs4/Kconfig~autofs-update-fs-autofs4-kconfig > fs/autofs4/Kconfig > --- a/fs/autofs4/Kconfig~autofs-update-fs-autofs4-kconfig > +++ a/fs/autofs4/Kconfig > @@ -1,5 +1,7 @@ > config AUTOFS4_FS > - tristate "Kernel automounter version 4 support (also supports v3)" > + tristate "Kernel automounter version 4 support (also supports v3 and > v5)" > + default n > + depends on AUTOFS_FS = n > help > The automounter is a tool to automatically mount remote file > systems > on demand. This implementation is partially kernel-based to reduce > @@ -7,14 +9,32 @@ config AUTOFS4_FS > automounter (amd), which is a pure user space daemon. > > To use the automounter you need the user-space tools from > - <https://www.kernel.org/pub/linux/daemons/autofs/v4/>; you also > - want to answer Y to "NFS file system support", below. > + <https://www.kernel.org/pub/linux/daemons/autofs/>; you also want > + to answer Y to "NFS file system support", below. > > - To compile this support as a module, choose M here: the module will > be > - called autofs4. You will need to add "alias autofs autofs4" to > your > - modules configuration file. > - > - If you are not a part of a fairly large, distributed network or > - don't have a laptop which needs to dynamically reconfigure to the > - local network, you probably do not need an automounter, and can say > - N here. > + This module is in the process of being renamed from autofs4 to > + autofs. Since autofs is now the only module that provides the > + autofs file system the module is not version 4 specific. > + > + The autofs4 module is now built from the source located in > + fs/autofs. The autofs4 directory and its configuration entry > + will be removed two kernel versions from the inclusion of this > + change. > + > + Changes that will need to be made should be limited to: > + - source include statments should be changed from autofs_fs4.h to > + autofs_fs.h since these two header files have been merged. > + - user space scripts that manually load autofs4.ko should be > + changed to load autofs.ko. But since the module directory name > + and the module name are the same as the file system name there > + is no need to manually load module. > + - any "alias autofs autofs4" will need to be removed. > + > + Please configure AUTOFS_FS instead of AUTOFS4_FS from now on. > + > + NOTE: Since the modules autofs and autofs4 use the same file system > + type name of "autofs" only one can be built. The "depends" > + above will result in AUTOFS4_FS not appearing in .config for > + any setting of AUTOFS_FS other than n and AUTOFS4_FS will > + appear under the AUTOFS_FS entry otherwise which is intended > + to draw attention to the module rename change. > _ >
