On Wed, Apr 04, 2007 at 11:52:57PM -0700, Jeremy Fitzhardinge wrote: > Matt Mackall wrote: > >> +/* > >> + * Scan a region of virtual memory, filling in page tables as necessary > >> + * and calling a provided function on each leaf page table. > >> + */ > >> > > > > But I'm not sure what the use case is that wants filling in the page > > table..? If both modes really make sense, perhaps a flag could unify > > these differences. > > > > Well, two reasons: > > One is the general one that if you're traversing ptes then they need to > exist to traverse them (for example, if you're creating new mappings). > Obviously if you want to just visit existing mappings, then > instantiating new pagetable is not the right thing to do (and I could > make use of this too). > > The other is that there are various places in the Xen hypervisor API > where you pass in a reference to pte entry for the hypervisor to put > mappings into, and the rest of the pagetable needs to exist. The Xen > code uses the side-effect of apply_to_page_range() to create pagetable > for these calls.
I think adding a flags field and an allocate flag to my callback struct would be sufficient here. > > I'd gotten the impression that these sorts of typedefs were out of > > fashion. > > > > In general yes, but for function pointers the syntax is so clumsy that I > think typedefs are OK. The syntax is horrible, but I don't think we end up using the resultant type enough to justify the namespace pollution. -- Mathematics is the supreme nostalgia of our time. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
