Re: [Dump-devel] dump and largefiles

[Andrea A. <an...@su...>]

On Tue, Dec 19, 2000 at 05:04:21PM +0100, Stelian Pop wrote:
> On Tue, Dec 19, 2000 at 04:32:09PM +0100, Andrea Arcangeli wrote:
> 
> > On Tue, Dec 19, 2000 at 07:17:34AM -0800, ty...@va... wrote:
> > > If your application is known to be 64-bit clean, and won't get surprised
> > > by large files, it should use the ext2fs_block_iterate2 interface.
> > > Hence, a largefile-knowledgeable version dump should not require a
> > > special version of e2fsprogs/libext2fs.  The ext2fs_block_iterate2
> > > interface has been around since version 1.12.
> > 
> > Great. So in short we don't need to touch e2fsprogs to fix dump ;))
> 
> So, if I got all this right:
>         - we don't touch e2fsprogs
>         - your patch for dump remains correct
>         - we use ext2fs_block_iterate2 instead of ext2fs_block_iterate

yes.

>         (probably needs some little cosmetic fixes here in the 
>         callback function since the block number is > 2^32)
>         - we forget about the -D_FILE_OFFSET_BITS=64, in both dump 
>         and e2fsprogs

No! We forget about -D_FILE_OFFSET_BITS=64 _only_ in e2fsprogs.

> With all this, we get one dump binary which will be able to deal with
> large files on both LFS and non-LFS systems (LFS system accessed from
> a non-LFS system).

No, we simply can't generate largefiles in a non-LFS system during restore.

Dump could even work without largefile support from glibc, but not restore
as far I can tell.

We have to restore those files through the fs, not via blockdevice through
e2fsprogs.

> Of course, restore will truncate the result if ran on non-LFS systems,
> but that's not very important IMHO...

And that's why we need to use glibc LFS support in the LFS systems so we
can actually restore the largefiles ;)

> Andrea, could you make those changes to your patch and test on your
> test files ?

The only change is "not touch e2fsprogs" and use ext2fs_block_iterate2
instead of ext2fs_block_iterate, and that's what I'm doing right now.

Andrea