[PATCH] fs: btrfs: remove the usage of undeclared fs_mutex variable

[Pankaj Raghav]

> Which branch is the code based on?
> 
I actually cloned it from u-boot github master.
https://github.com/u-boot/u-boot/blob/f117c54cc83e3c519883edb5a48062644d38c443/fs/btrfs/disk-io.c#L785

> I don't believe it's upstream, as such compiling error should be exposed
> very easily.
>
Actually, I was also surprised but the compiler did not give me any error
because the mutex definition was as follows:
#define mutex_init(...)

and the compiler did not generate any error because we don't do anything
the parameter.

>> ---
>>   fs/btrfs/disk-io.c | 2 --
>>   1 file changed, 2 deletions(-)
>>
>> diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
> 
> Furthermore at current upstream HEAD a1375562c0a8 ("Merge tag
> 'x86_urgent_for_v6.0-rc8' of
> git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip"), there is no
> btrfs_new_fs_info() function defined anyway.
>
Hmm, I sent these patches for u-boot. Maybe there is a misunderstanding
here? :)

> THanks,
> Qu
> 
>> index 8043abc1bd..c80f8e8028 100644
>> --- a/fs/btrfs/disk-io.c
>> +++ b/fs/btrfs/disk-io.c
>> @@ -782,8 +782,6 @@ struct btrfs_fs_info *btrfs_new_fs_info(void)
>>       fs_info->fs_root_tree = RB_ROOT;
>>       cache_tree_init(&fs_info->mapping_tree.cache_tree);
>>   -    mutex_init(&fs_info->fs_mutex);
>> -
>>       return fs_info;
>>   free_all:
>>       btrfs_free_fs_info(fs_info);