Return-Path: linux-nfs-owner@vger.kernel.org Received: from mail-qg0-f48.google.com ([209.85.192.48]:33046 "EHLO mail-qg0-f48.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751030AbaHOLOw (ORCPT ); Fri, 15 Aug 2014 07:14:52 -0400 Received: by mail-qg0-f48.google.com with SMTP id i50so2065957qgf.21 for ; Fri, 15 Aug 2014 04:14:52 -0700 (PDT) From: Jeff Layton Date: Fri, 15 Aug 2014 07:14:50 -0400 To: Kinglong Mee Cc: Jeff Layton , "J. Bruce Fields" , Linux NFS Mailing List , Trond Myklebust , linux-fsdevel@vger.kernel.org Subject: Re: [PATCH 2/5 v3] locks: Copy all infomation for conflock Message-ID: <20140815071450.498949d8@tlielax.poochiereds.net> In-Reply-To: <53ED4F30.4060308@gmail.com> References: <53BAAAC5.9000106@gmail.com> <53E22EA5.70708@gmail.com> <20140809065112.700e0ecc@tlielax.poochiereds.net> <53E791F1.40802@gmail.com> <53ED4F30.4060308@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Sender: linux-nfs-owner@vger.kernel.org List-ID: On Fri, 15 Aug 2014 08:07:12 +0800 Kinglong Mee wrote: > Commit d5b9026a67 ([PATCH] knfsd: locks: flag NFSv4-owned locks) using > fl_lmops field in file_lock for checking nfsd4 lockowner. > > But, commit 1a747ee0cc (locks: don't call ->copy_lock methods on return > of conflicting locks) causes the fl_lmops of conflock always be NULL. > > Also, commit 0996905f93 (lockd: posix_test_lock() should not call > locks_copy_lock()) caused the fl_lmops of conflock always be NULL too. > > Make sure copy the private information by fl_copy_lock() in struct > file_lock_operations, merge __locks_copy_lock() to fl_copy_lock(). > > v3: Update based on Joe and Jeff's patch. > > Signed-off-by: Kinglong Mee > --- > fs/locks.c | 24 +++++++----------------- > include/linux/fs.h | 6 ------ > 2 files changed, 7 insertions(+), 23 deletions(-) > > diff --git a/fs/locks.c b/fs/locks.c > index cb66fb0..fe52abb 100644 > --- a/fs/locks.c > +++ b/fs/locks.c > @@ -281,33 +281,23 @@ static void locks_copy_private(struct file_lock *new, struct file_lock *fl) > /* > * Initialize a new lock from an existing file_lock structure. > */ > -void __locks_copy_lock(struct file_lock *new, const struct file_lock *fl) > +void locks_copy_lock(struct file_lock *new, struct file_lock *fl) > { > + /* "new" must be a freshly-initialized lock */ > + WARN_ON_ONCE(new->fl_ops); > + > new->fl_owner = fl->fl_owner; > new->fl_pid = fl->fl_pid; > - new->fl_file = NULL; > + new->fl_file = fl->fl_file; > new->fl_flags = fl->fl_flags; > new->fl_type = fl->fl_type; > new->fl_start = fl->fl_start; > new->fl_end = fl->fl_end; > new->fl_ops = NULL; > new->fl_lmops = NULL; > -} > -EXPORT_SYMBOL(__locks_copy_lock); > - > -void locks_copy_lock(struct file_lock *new, struct file_lock *fl) > -{ > - /* "new" must be a freshly-initialized lock */ > - WARN_ON_ONCE(new->fl_ops); > - > - __locks_copy_lock(new, fl); > - new->fl_file = fl->fl_file; > - new->fl_ops = fl->fl_ops; > - new->fl_lmops = fl->fl_lmops; > > locks_copy_private(new, fl); > } > - > EXPORT_SYMBOL(locks_copy_lock); > > static inline int flock_translate_cmd(int cmd) { > @@ -735,7 +725,7 @@ posix_test_lock(struct file *filp, struct file_lock *fl) > break; > } > if (cfl) { > - __locks_copy_lock(fl, cfl); > + locks_copy_lock(fl, cfl); > if (cfl->fl_nspid) > fl->fl_pid = pid_vnr(cfl->fl_nspid); > } else > @@ -941,7 +931,7 @@ static int __posix_lock_file(struct inode *inode, struct file_lock *request, str > if (!posix_locks_conflict(request, fl)) > continue; > if (conflock) > - __locks_copy_lock(conflock, fl); > + locks_copy_lock(conflock, fl); > error = -EAGAIN; > if (!(request->fl_flags & FL_SLEEP)) > goto out; > diff --git a/include/linux/fs.h b/include/linux/fs.h > index 908af4f..a383a30 100644 > --- a/include/linux/fs.h > +++ b/include/linux/fs.h > @@ -966,7 +966,6 @@ void locks_free_lock(struct file_lock *fl); > extern void locks_init_lock(struct file_lock *); > extern struct file_lock * locks_alloc_lock(void); > extern void locks_copy_lock(struct file_lock *, struct file_lock *); > -extern void __locks_copy_lock(struct file_lock *, const struct file_lock *); > extern void locks_remove_posix(struct file *, fl_owner_t); > extern void locks_remove_file(struct file *); > extern void locks_release_private(struct file_lock *); > @@ -1026,11 +1025,6 @@ static inline void locks_init_lock(struct file_lock *fl) > return; > } > > -static inline void __locks_copy_lock(struct file_lock *new, struct file_lock *fl) > -{ > - return; > -} > - > static inline void locks_copy_lock(struct file_lock *new, struct file_lock *fl) > { > return; I'm not sure this is really what you want to do. Calling fl_copy_lock for a conflock looks relatively harmless for nfs and nlm. AFS though seems to add the lock to a list associated with the inode. That seems a little suspicious for a conflock and could be problematic. It may be best to avoid dealing with fl_ops for a conflock. Also in the case of fcntl_getlk, the struct file_lock lives on the stack, and locks_release_private is never called on it. You'll need to audit all of the current callers of __locks_copy_lock to ensure that any resources you end up taking references on when copying the conflock are eventually released. -- Jeff Layton