From mboxrd@z Thu Jan 1 00:00:00 1970 From: Steffen Persvold Date: Wed, 09 Jan 2002 20:01:13 +0000 Subject: Re: [Linux-ia64] Re: Status on ioremap patch Message-Id: List-Id: References: In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-ia64@vger.kernel.org Steffen Persvold wrote: > > David Mosberger wrote: > > > > Steffen, > > > > I looked at your patch and have a comment and a suggestion. First, I > > do not think it's safe to define ioremap() as a way to install > > write-cached mappings. There are plenty of drivers left that use > > ioremap() instead of ioremap_nocache() and we can't change the > > semantics of ioremap() underneath them. > > > > Second, it seems to me it would be cleaner to extend > > remap_page_range() to allow remapping into the kernel mapped segment > > (region 5 in the case of ia64 linux). This should work as is, except > > that in the kernel case, you need to use pgd_offset_k(). I think you > > could hack mm/memory.c to check whether "from" is in the range from > > VMALLOC_START to VMALLOC_END and, if so, use pgd_offset_k() instead of > > pgd_offset(). Can you try this and let me know if it works for your > > needs? > > > > I've had some time to look at it, and I decided to do what you said. I also changed ioremap on all > platforms that implements it so that they use remap_page_range()). I've tested the patch on IA64 and > i386. > > I've attached the patch (I didn't post it on the lkml even though it affects more that the IA64 > platform), it's against a vanilla 2.4.17 tree. > > Please take a look and tell me what you think. > So, what about this patch (posted earlier) David ? Have you seen the comments from Keith ? Regards, -- Steffen Persvold | Scalable Linux Systems | Try out the world's best mailto:sp@scali.no | http://www.scali.com | performing MPI implementation: Tel: (+47) 2262 8950 | Olaf Helsets vei 6 | - ScaMPI 1.12.2 - Fax: (+47) 2262 8951 | N0621 Oslo, NORWAY | >300MBytes/s and <4uS latency