Messages in this thread | | | From | "H. Peter Anvin" <> | Subject | Re: partially encrypted filesystem | Date | 3 Dec 2003 19:59:47 -0800 |
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Followup to: <3FCE8CF5.4030006@pobox.com> By author: Jeff Garzik <jgarzik@pobox.com> In newsgroup: linux.dev.kernel > > Linus Torvalds wrote: > > With an encrypted filesystem, you can't do that. Or rather: you can do it > > if the filesystem is read-only, but you definitely CANNOT do it on > > writing. For writing you have to marshall the output buffer somewhere > > else (and quite frankly, it tends to become a lot easier if you can do > > that for reading too). > > > > And that in turn causes problems. You get all kinds of interesting > > deadlock schenarios when write-out requires more memory in order to > > succeed. So you need to get careful. Reading ends up being the much easier > > case (doesn't have the same deadlock issues _and_ you could do it in-place > > anyway). > > > FWIW zisofs and ntfs have to do this too, since X on-disk compressed > pages must be expanded to X+Y in-memory pages... >
zisofs is read-only, so it doesn't apply.
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