On Sun, Sep 14, 2008 at 01:58:10PM -0400, Theodore Tso wrote: > On Sun, Sep 14, 2008 at 09:48:59AM -0400, Christoph Hellwig wrote: > > Let's make it clear, I've said to not add it unless we have users. And > > What Anton brought up is exactly the reason for that - to support > > encrypted extents we actually need more information in the structure. > > That's why we need to have this broad and sometimes a little slow > > discussion on fsdevel instead of just rushing in some flag for future > > use that won't make any sense in the end. > > You're incorrect here. Encrypted extents does not require any > additional information in the structure. Compressed extents are a bit > more useful if we allow the the filesystem to return the amount of > space used on the storage device, Sorry, should have written compressed and not encrypted above. > cramfs). But that being said, the fundamental question here is > whether we should try to plan for future users of the data structure, > and reserve space now for the, or not. Your approach of saying Nein! > Nein! Nein! for every single feature where we don't have > implementation pretty much guarantees that we will need to expand the > structure later to make room for these extra fields, and then we'll > need to define a new ioctl and have similar complexity to the stat > system call to support multiple userspace interfaces. If we try to > anticipate new users in advance, then there is at least a *chance* > we'll get it right up front. I agree to you (or someone elses - don't remember anymore) suggestion to put in more padding so we can add fields later. I strongly disagree putting in features now that we neither have a user, nor a usecase or testcase for. -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
