From owner-freebsd-commit  Tue Sep  5 16:29:03 1995
Return-Path: commit-owner
Received: (from majordom@localhost)
          by freefall.freebsd.org (8.6.11/8.6.6) id QAA10603
          for freebsd-commit-outgoing; Tue, 5 Sep 1995 16:29:03 -0700
Received: (from majordom@localhost)
          by freefall.freebsd.org (8.6.11/8.6.6) id QAA10590
          for cvs-all-outgoing; Tue, 5 Sep 1995 16:29:01 -0700
Received: (from majordom@localhost)
          by freefall.freebsd.org (8.6.11/8.6.6) id QAA10577
          for cvs-sys-outgoing; Tue, 5 Sep 1995 16:29:00 -0700
Received: from Root.COM (implode.Root.COM [198.145.90.17])
          by freefall.freebsd.org (8.6.11/8.6.6) with ESMTP id QAA10567
          ; Tue, 5 Sep 1995 16:28:53 -0700
Received: from corbin.Root.COM (corbin [198.145.90.34]) by Root.COM (8.6.12/8.6.5) with ESMTP id QAA01460; Tue, 5 Sep 1995 16:27:49 -0700
Received: from localhost (localhost [127.0.0.1]) by corbin.Root.COM (8.6.11/8.6.5) with SMTP id QAA25464; Tue, 5 Sep 1995 16:29:45 -0700
Message-Id: <199509052329.QAA25464@corbin.Root.COM>
To: Stefan Esser <se@freefall.freebsd.org>, CVS-commiters@freefall.freebsd.org,
        cvs-sys@freefall.freebsd.org
Subject: Re: cvs commit: src/sys/pci ncr.c 
In-reply-to: Your message of "Tue, 05 Sep 95 15:59:38 PDT."
             <199509052259.PAA25428@corbin.Root.COM> 
From: David Greenman <davidg@Root.COM>
Reply-To: davidg@Root.COM
Date: Tue, 05 Sep 1995 16:29:45 -0700
Sender: commit-owner@FreeBSD.org
Precedence: bulk

>>se          95/09/05 15:38:02
>>
>>  Modified:    sys/pci   ncr.c
>>  Log:
>>  The NCR script has grown beyond one page (4KB). Since malloc() returns
>>  contiguous memory in virtual space, but doesn't guarantee any particular
>>  physical layout of pages, the script may be not contguous in physical
>>  memory. This made the first write command fail in very rare cases.
>>  This has been fixed by checking the region returned by malloc() for
>>  being contiguous, but there should be a physical memory allocate
>>  and later mapping to virtual memory instead.
>>  
>>  A few assertions and error messages are improved.
>
>   I wrote a routine specifically for allocating physically contiguous memory.
>Take a look at vm_page_alloc_contig() in vm/vm_page.c.

   BTW, this routine is designed to only be called during system startup. If
you need to allocate the memory dynamically, then this won't work...

-DG