Re: [PATCH] fs: Rename the parameter of mnt_get_write_access()

[Zizhi Wo]

在 2025/5/16 18:31, Jan Kara 写道:
> On Fri 16-05-25 11:21:47, Zizhi Wo wrote:
> > From: Zizhi Wo <wozizhi@xxxxxxxxxx>
> >
> > Rename the parameter in mnt_get_write_access() from "m" to "mnt" for
> > consistency between declaration and implementation.
> >
> > Signed-off-by: Zizhi Wo <wozizhi@xxxxxxxxxx>
>
> I'm sorry but this is just a pointless churn. I agree the declaration and
> implementation should better be consistent (although in this particular
> case it isn't too worrying) but it's much easier (and with much lower
> chance to cause conflicts) to just fixup the declaration.
>
> 								Honza

Yes, I had considered simply fixing the declaration earlier. However, in
the include/linux/mount.h file, similar functions like
"mnt_put_write_access" use "mnt" as the parameter name rather than "m",
just like "mnt_get_write_access". So I chose to modify the function
implementation directly, although this resulted in a larger amount of
changes. So as you can see, for simplicity, I will directly update the
parameter name in the function declaration in the second version.

Thanks,
Zizhi Wo

> > ---
> >   fs/namespace.c | 14 +++++++-------
> >   1 file changed, 7 insertions(+), 7 deletions(-)
> >
> > diff --git a/fs/namespace.c b/fs/namespace.c
> > index 1b466c54a357..b1b679433ab3 100644
> > --- a/fs/namespace.c
> > +++ b/fs/namespace.c
> > @@ -483,7 +483,7 @@ static int mnt_is_readonly(struct vfsmount *mnt)
> >    */
> >   /**
> >    * mnt_get_write_access - get write access to a mount without freeze protection
> > - * @m: the mount on which to take a write
> > + * @mnt: the mount on which to take a write
> >    *
> >    * This tells the low-level filesystem that a write is about to be performed to
> >    * it, and makes sure that writes are allowed (mnt it read-write) before
> > @@ -491,13 +491,13 @@ static int mnt_is_readonly(struct vfsmount *mnt)
> >    * frozen. When the write operation is finished, mnt_put_write_access() must be
> >    * called. This is effectively a refcount.
> >    */
> > -int mnt_get_write_access(struct vfsmount *m)
> > +int mnt_get_write_access(struct vfsmount *mnt)
> >   {
> > -	struct mount *mnt = real_mount(m);
> > +	struct mount *m = real_mount(mnt);
> >   	int ret = 0;
> >   
> >   	preempt_disable();
> > -	mnt_inc_writers(mnt);
> > +	mnt_inc_writers(m);
> >   	/*
> >   	 * The store to mnt_inc_writers must be visible before we pass
> >   	 * MNT_WRITE_HOLD loop below, so that the slowpath can see our
> > @@ -505,7 +505,7 @@ int mnt_get_write_access(struct vfsmount *m)
> >   	 */
> >   	smp_mb();
> >   	might_lock(&mount_lock.lock);
> > -	while (READ_ONCE(mnt->mnt.mnt_flags) & MNT_WRITE_HOLD) {
> > +	while (READ_ONCE(m->mnt.mnt_flags) & MNT_WRITE_HOLD) {
> >   		if (!IS_ENABLED(CONFIG_PREEMPT_RT)) {
> >   			cpu_relax();
> >   		} else {
> > @@ -530,8 +530,8 @@ int mnt_get_write_access(struct vfsmount *m)
> >   	 * read-only.
> >   	 */
> >   	smp_rmb();
> > -	if (mnt_is_readonly(m)) {
> > -		mnt_dec_writers(mnt);
> > +	if (mnt_is_readonly(mnt)) {
> > +		mnt_dec_writers(m);
> >   		ret = -EROFS;
> >   	}
> >   	preempt_enable();
> > --
> > 2.39.2