On Mon, Jun 08, 2009 at 11:42:53PM -0700, Eric W. Biederman wrote: > Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> writes: > > > On Mon, 8 Jun 2009, Al Viro wrote: > >> > >> Sure, even though I'm not at all certain that copy_from_user() is that easy. > >> We can make locking current->mm in there interruptible, all right, but that's > >> only a part of the answer - even aside of the allocations, we'd need vma > >> ->fault() interruptible as well, which leads to interruptible instances of > >> ->readpage(), with all the fun _that_ would be. > > > > We already have all that - the NFS people wanted it. > > > > More importantly, you don't actually need to interrupt readpage itself - > > you just need to stop _waiting_ on it. So in your fault handler, just stop > > waiting, and instead just return FAULT_RETRY or whatever. > > That sounds doable. Has that code been merged yet? > > I took a quick look and it didn't see anyone breaking out of page fault with a > signal or code to really handle that. The problem is get_user_pages I think. Now that we have a good number of fault flags, we can pass down whether the caller is able to be interrupted or not. Ben H had some interest in doing this, but I don't know how far he got with it. -- 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
