[openib-general] Re: [PATCH 11/16] IB uverbs: add mthca mmap support

[Roland Dreier]

    Andrew> What's the thinking behind the VM_DONTCOPY there?

As I said before, I don't think the thinking behind VM_DONTCOPY was
correct thinking.  Let's take it out.

I've now answered all your questions on this patchset (or at least
written something in response to all your questions ;).  What's your
feeling on merging?  If more info is required, just let me know.  I'll
also be at the kernel summit in a couple of weeks if you want to go
over it in person.

 - R.


There's no need to set VM_DONTCOPY when mmap()ing the hardware
doorbell page into userspace.

Signed-off-by: Roland Dreier <rolandd at cisco.com>


--- linux-export.orig/drivers/infiniband/hw/mthca/mthca_provider.c	2005-06-28 15:20:28.000000000 -0700
+++ linux-export/drivers/infiniband/hw/mthca/mthca_provider.c	2005-07-05 12:14:20.838664330 -0700
@@ -347,7 +347,6 @@
 		return -EINVAL;
 
 	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
-	vma->vm_flags    |= VM_DONTCOPY;
 
 	if (remap_pfn_range(vma, vma->vm_start,
 			    to_mucontext(context)->uar.pfn,