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

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

[Pankaj Raghav]

This line probably got in by mistake as there is no fs_mutex member in
the btrfs_fs_info struct.

Signed-off-by: Pankaj Raghav <p.raghav@samsung.com>
---
 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
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);
-- 
2.25.1

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

[Qu Wenruo]

On 2022/9/27 17:55, Pankaj Raghav wrote:
> This line probably got in by mistake as there is no fs_mutex member in
> the btrfs_fs_info struct.
> 
> Signed-off-by: Pankaj Raghav <p.raghav@samsung.com>

Which branch is the code based on?

I don't believe it's upstream, as such compiling error should be exposed 
very easily.

> ---
>   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.

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);

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

[Qu Wenruo]

On 2022/9/27 18:39, Qu Wenruo wrote:
> 
> 
> On 2022/9/27 17:55, Pankaj Raghav wrote:
>> This line probably got in by mistake as there is no fs_mutex member in
>> the btrfs_fs_info struct.
>>
>> Signed-off-by: Pankaj Raghav <p.raghav@samsung.com>
> 
> Which branch is the code based on?
> 
> I don't believe it's upstream, as such compiling error should be exposed 
> very easily.
> 
>> ---
>>   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.

My bad, I didn't notice it's for Uboot, not kernel.

In that case, you can safely remove it, but it won't cause compile error 
since in <linux/compat.h>, we define mutex_init() as noop, thus it 
doesn't cause any compile error.

Anyway the patch itself looks good, I also checked if there is other 
mutex related usage, and this is the only one.

Reviewed-by: Qu Wenruo <wqu@suse.com>

Thanks,
Qu

> 
> 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);

Re: [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);

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

[Qu Wenruo]

On 2022/9/27 18:49, Pankaj Raghav wrote:
> 
> 
>> 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? :)

Yeah, you're completely right, I thought it's for kernel by default...

Sorry for the confusion.
Qu

> 
>> 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);