Re: [PATCH 06/16] GFS2: dentry, export, super and vm operations

[Jan Engelhardt <jengelh@linux01.gwdg.de>]

>> >> >+	if (IS_ERR(inode))
>> >> >+		return ERR_PTR(PTR_ERR(inode));
>> >> 
>> >> Just return inode.
>> >
>> >The function returns a dentry, so it would need to be casted and I
>> >thought that would look "more odd" than this construction.
>> 
>> Yes, it is very odd indeed that you return an inode as a dentry at all. How is
>> the caller supposed to know whether it was an inode or dentry that was actually
>> returned?
>> 
>
>This is dealing with the error case only. If the function being called
>returns an error (signaled by IS_ERR(inode) - hence an invalid pointer

Seems reasonable. Would you like to add a comment? (Possibly a little 
shorter than this good explanation, maybe

	/* In case of an error, @inode carries the error value, and we
	have to return that. */

>value) then we need to return that error to the calling routing. Since
>this function in question returns a dentry, we convert the invalid
>pointer value from the function returning an inode into an integer and
>then covert the integer into an invalid pointer value again, but this
>time its an invalid pointer to a dentry and hence the correct return
>type for this function.



Jan Engelhardt
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