Re: [PATCH 1/3 v2] fs/locks.c: Copy all information for conflock

[Kinglong Mee <kinglongmee@gmail.com>]

On 8/12/2014 00:19, Jeff Layton wrote:
> On Sun, 10 Aug 2014 23:38:25 +0800
> Kinglong Mee <kinglongmee@gmail.com> 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.
>>
>> v2: Only change the order from 3/3 to 1/3 now.
>>
>> Signed-off-by: Kinglong Mee <kinglongmee@gmail.com>
>> ---
>>  fs/lockd/svclock.c |  2 +-
>>  fs/locks.c         | 25 ++++++-------------------
>>  include/linux/fs.h |  6 ------
>>  3 files changed, 7 insertions(+), 26 deletions(-)
>>
>> diff --git a/fs/lockd/svclock.c b/fs/lockd/svclock.c
>> index ab798a8..e1f209c 100644
>> --- a/fs/lockd/svclock.c
>> +++ b/fs/lockd/svclock.c
>> @@ -677,7 +677,7 @@ nlmsvc_update_deferred_block(struct nlm_block *block, struct file_lock *conf,
>>  		block->b_flags |= B_TIMED_OUT;
>>  	if (conf) {
>>  		if (block->b_fl)
>> -			__locks_copy_lock(block->b_fl, conf);
>> +			locks_copy_lock(block->b_fl, conf);
>>  	}
>>  }
>>  
>> diff --git a/fs/locks.c b/fs/locks.c
>> index 717fbc4..91b0f03 100644
>> --- a/fs/locks.c
>> +++ b/fs/locks.c
>> @@ -266,35 +266,22 @@ static void locks_copy_private(struct file_lock *new, struct file_lock *fl)
>>  		new->fl_lmops = fl->fl_lmops;
>>  }
>>  
>> -/*
>> - * 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)
>>  {
>> +	locks_release_private(new);
>> +
>>  	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)
>> -{
>> -	locks_release_private(new);
>> -
>> -	__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);
>>  }
> 
> (cc'ing Joe Perches)
> 
> Ok, so you're basically just reverting 1a747ee0cc11a19. The catch there
> is that you now need to ensure that any conflock structures are
> properly initialized before passing them to locks_copy_lock.
> 
> The nfsv4 server code currently doesn't do that and it will need to be
> fixed to do so or that will be a regression.

I don't think so.
locks_alloc_lock() has initialize the file_lock struct,
the same as locks_init_lock().

I will clean the duplicate initialize for file_lock in nfs4state.c in v3.

> For the NLM code, Joe Perches has proposed a patch to remove the
> conflock parameter from lm_grant since the callers always pass in NULL
> anyway. You may want to pull in his patch and rebase yours on top of it
> since it'll remove that __locks_copy_lock call altogether.
> 
> Joe, is Andrew merging that patch or do I need to pull it into the
> locks tree?

I will update this patch based on that patch and your new patch for locks.c.

thanks,
Kinglong Mee

> 
>> -
>>  EXPORT_SYMBOL(locks_copy_lock);
>>  
>>  static inline int flock_translate_cmd(int cmd) {
>> @@ -718,7 +705,7 @@ 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
>> @@ -921,7 +908,7 @@ 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 e11d60c..ced023d 100644
>> --- a/include/linux/fs.h
>> +++ b/include/linux/fs.h
>> @@ -941,7 +941,6 @@ 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 *);
>> @@ -1001,11 +1000,6 @@ 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;
> 
>