From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paul Mundt Subject: Re: [PATCH 13/14] Pramfs: Write Protection Date: Thu, 18 Jun 2009 11:57:36 +0900 Message-ID: <20090618025736.GB26531@linux-sh.org> References: <4A392098.9060205@gmail.com> Mime-Version: 1.0 Return-path: Content-Disposition: inline In-Reply-To: <4A392098.9060205@gmail.com> Sender: linux-fsdevel-owner@vger.kernel.org List-ID: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Marco Cc: Linux FS Devel , linux@arm.linux.org.uk, linux-m68k@lists.linux-m68k.org, uclinux-dist-devel@blackfin.uclinux.org, Linux Embedded , Linux Kernel , Daniel Walker On Wed, Jun 17, 2009 at 06:58:00PM +0200, Marco wrote: > Jared Hulbert wrote: > > > Why not just fix flush_tlb_range()? > > > > > > If an arch has a flush_tlb_kernel_page() that works then it stands to > > > reason that the flush_tlb_kernel_range() shouldn't work with minimal > > > effort, no? > > > > flush_tlb_kernel_page() is a new one to me, it doesn't have any mention > > in Documentation/cachetlb.txt anyways. > > > > Many of the flush_tlb_kernel_range() implementations do ranged checks > > with tunables to determine whether it is more expensive to selectively > > flush vs just blowing the entire TLB away. > > > > Likewise, there is no reason why those 4 architectures can not just shove > > that if (end <= start + PAGE_SIZE) check in the beginning of their > > flush_tlb_kernel_range() and fall back on flush_tlb_kernel_page() for > > those cases. Hiding this in generic code is definitely not the way to go. > > Ok I'll change that function at arch level and I'll remove the ifdef, > I'll call only flush_tlb_kernel_page(), but I'd like to know what is > the opinion of the arch maintainers to do that. (Who is the maintainer > of H8300 arch?) > No, you should call flush_tlb_kernel_range() and just fix up the flush_tlb_kernel_range() calls to wrap in to flush_tlb_kernel_page(). As far as the kernel is concerned, flush_tlb_kernel_page() is not a standard interface, as it has no mention in Documentation/cachetlb.txt. flush_tlb_page() and flush_tlb_kernel_range() on the other hand are both standard interfaces. H8300 is a nommu platform, so it has no TLB to flush. Yoshinori Sato is the maintainer. Consult the MAINTAINERS file, that's what it is there for.