On Tue, Aug 15, 2017 at 5:42 AM, Jan Kara <jack@xxxxxxx> wrote: > On Mon 14-08-17 23:12:22, Dan Williams wrote: >> diff --git a/include/linux/mm_types.h b/include/linux/mm_types.h >> index ff151814a02d..73fdc0ada9ee 100644 >> --- a/include/linux/mm_types.h >> +++ b/include/linux/mm_types.h >> @@ -306,6 +306,7 @@ struct vm_area_struct { >> struct mm_struct *vm_mm; /* The address space we belong to. */ >> pgprot_t vm_page_prot; /* Access permissions of this VMA. */ >> unsigned long vm_flags; /* Flags, see mm.h. */ >> + unsigned long fs_flags; /* fs flags, see MAP_DIRECT etc */ >> >> /* >> * For areas with an address space and backing store, > > Ah, OK, here are VMA flags I was missing in the previous patch :) But why > did you create separate fs_flags field for this? on 64-bit archs there's > still space in vm_flags and frankly I don't see why we should separate > MAP_DIRECT or MAP_SYNC from other flags? Where would MAP_DIRECT go in the 32-bit case? > After all a difference in these > flags must also prevent VMA merging (which you forgot to handle I think) > and they need to be copied on split (which happens by chance even now). Ah, yes I did miss blocking the merge of a vma with MAP_DIRECT and one without. However, the vma split path looks ok. -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html