[Devel] [PATCH] fs/fuse: set FATTR_FH flag on mtime file flush

[Pavel Butsykin]

On 05.06.2018 12:53, Kirill Tkhai wrote:
> On 04.06.2018 16:57, Pavel Butsykin wrote:
>> If setattr request is for a file, FATTR_FH flag should be set.
>> In fuse_flush_mtime() that is clearly missed.
>>
>> This fix is present in commit 1e18bda, but it wasn't backported because
>> the commit has a lot of unrelated changes. So this patch can be safely dropped
>> in case of moving to a newer kernel.
>>
>> #VSTOR-10676
>>
>> Signed-off-by: Pavel Butsykin <pbutsykin at virtuozzo.com>
>> ---
>>   fs/fuse/dir.c    | 6 +++++-
>>   fs/fuse/file.c   | 4 ++--
>>   fs/fuse/fuse_i.h | 2 +-
>>   3 files changed, 8 insertions(+), 4 deletions(-)
>>
>> diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c
>> index 0ae0344be3c5..b04023bf230a 100644
>> --- a/fs/fuse/dir.c
>> +++ b/fs/fuse/dir.c
>> @@ -1690,7 +1690,7 @@ static void fuse_setattr_fill(struct fuse_conn *fc, struct fuse_req *req,
>>   /*
>>    * Flush inode->i_mtime to the server
>>    */
>> -int fuse_flush_mtime(struct file *file, bool nofail)
>> +int fuse_flush_mtime(struct file *file, struct fuse_file *ff, bool nofail)
>>   {
>>   	struct inode *inode = file->f_mapping->host;
>>   	struct fuse_inode *fi = get_fuse_inode(inode);
>> @@ -1715,6 +1715,10 @@ int fuse_flush_mtime(struct file *file, bool nofail)
>>   	inarg.mtime = inode->i_mtime.tv_sec;
>>   	inarg.mtimensec = inode->i_mtime.tv_nsec;
>>   
>> +	if (ff) {
>> +		inarg.valid |= FATTR_FH;
>> +		inarg.fh = ff->fh;
>> +	}
>>   	fuse_setattr_fill(fc, req, inode, &inarg, &outarg);
>>   	fuse_request_send(fc, req);
>>   	err = req->out.h.error;
>> diff --git a/fs/fuse/file.c b/fs/fuse/file.c
>> index 53e81bdca6ed..ddfb41af54ec 100644
>> --- a/fs/fuse/file.c
>> +++ b/fs/fuse/file.c
>> @@ -458,7 +458,7 @@ static int fuse_release(struct inode *inode, struct file *file)
>>   
>>   	if (test_bit(FUSE_I_MTIME_UPDATED,
>>   		     &get_fuse_inode(inode)->state))
>> -		fuse_flush_mtime(file, true);
>> +		fuse_flush_mtime(file, ff, true);
>>   
>>   	fuse_release_common(file, FUSE_RELEASE);
>>   
>> @@ -724,7 +724,7 @@ int fuse_fsync_common(struct file *file, loff_t start, loff_t end,
>>   
>>   	if (!datasync && test_bit(FUSE_I_MTIME_UPDATED,
>>   				  &get_fuse_inode(inode)->state)) {
>> -		err = fuse_flush_mtime(file, false);
>> +		err = fuse_flush_mtime(file, isdir ? NULL : ff, false);
> 
> Everything looks OK for me, and the only thing I want to ask you is the reason
> we ignore ff in case of directory. Why we should do this?

Because FATTR_FH flag indicates that request belongs to a file.
Correspondingly, this flag should be set for a directory.

> 
>>   		if (err)
>>   			goto out;
>>   	}
>> diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h
>> index f704fd17905b..939835f585b1 100644
>> --- a/fs/fuse/fuse_i.h
>> +++ b/fs/fuse/fuse_i.h
>> @@ -1074,7 +1074,7 @@ int fuse_dev_release(struct inode *inode, struct file *file);
>>   
>>   bool fuse_write_update_size(struct inode *inode, loff_t pos);
>>   
>> -int fuse_flush_mtime(struct file *file, bool nofail);
>> +int fuse_flush_mtime(struct file *file, struct fuse_file *ff, bool nofail);
>>   
>>   int fuse_do_setattr(struct inode *inode, struct iattr *attr,
>>   		    struct file *file);
>>