Re: PATCH 2.5.2.9: ext2 unbork fs.h (part 1/7)

Jeff Garzik
2002-01-07T21:37:52Z

Alexander Viro wrote:
> Now, the problems I see with Jeff's variant:
>
> a) if you make struct inode a part of ext2_inode - WTF bother with pointer?

You mean the typed pointer inside struct inode's union? Because I
needed a way to go from struct inode to struct ext2_inode_info,
-without- a nasty cast. inode->u.ext2_ip maintains the type information
without resorting to a nastier solution like an OFFSET_OF macro.
Suggestions for improvement welcome.

> b) ->destroy_inode() / ->clear_inode(). Merge them - that way it's one
> method.

Agreed. That would be [not yet written] patch8 in my plan.

> c) get_empty_inode() must die. Make it new_inode() and be done with that.
> And have socket.c explicitly set ->i_dev to NODEV afterwards.

In my patch get_empty_inode and new_inode are completely identical.
This is easy.

> d) ext2/balloc.c cleanup probably should be merged before.

I don't have an opinion on this one way or the other...

> I can live with "maintain refcounts in common part and leave allocation/freeing
> to filesystem". It's definitely better than allocating/freeing opaque objects
> in VFS using numeric fields in fs_type.

Yes... the opacity factor in the other patch bothers me.

> We will need to set very strict rules on passing around/storing pointers to
> ext2_inode and its ilk, though. There will be bugs when somebody just decides
> that keeping such pointers might be a good idea and forgets to be nice with
> ->i_count. Or decrement it manually instead of calling iput(), etc.

Not doing so now is a shoot-on-sight offense, I thought...

Jeff

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