From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Fri, 21 Apr 2006 09:33:15 +0200 From: Nick Piggin Subject: Re: [patch 1/5] mm: remap_vmalloc_range Message-ID: <20060421073315.GL21660@wotan.suse.de> References: <20060301045901.12434.54077.sendpatchset@linux.site> <20060301045910.12434.4844.sendpatchset@linux.site> <20060421001712.4cd5625e.akpm@osdl.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20060421001712.4cd5625e.akpm@osdl.org> Sender: owner-linux-mm@kvack.org Return-Path: To: Andrew Morton Cc: Nick Piggin , linux-kernel@vger.kernel.org, linux-mm@kvack.org List-ID: On Fri, Apr 21, 2006 at 12:17:12AM -0700, Andrew Morton wrote: > Nick Piggin wrote: > > > > Add a remap_vmalloc_range and get rid of as many remap_pfn_range and > > vm_insert_page loops as possible. > > > > remap_vmalloc_range can do a whole lot of nice range checking even > > if the caller gets it wrong (which it looks like one or two do). > > > > > > - if (remap_pfn_range(vma, start, page, PAGE_SIZE, PAGE_SHARED)) { > > - if (remap_pfn_range(vma, start, page, PAGE_SIZE, PAGE_SHARED)) { > > - if (remap_pfn_range(vma, start, page, PAGE_SIZE, PAGE_SHARED)) { > > - if (remap_pfn_range(vma, start, page, PAGE_SIZE, PAGE_SHARED)) > > - if (remap_pfn_range(vma, start, page, PAGE_SIZE, PAGE_SHARED)) { > > - if (remap_pfn_range(vma, start, page, PAGE_SIZE, PAGE_SHARED)) { > > - if (remap_pfn_range(vma, start, page, PAGE_SIZE, PAGE_SHARED)) > > - if (remap_pfn_range(vma, start, page, PAGE_SIZE, PAGE_SHARED)) > > - if (remap_pfn_range(vma, start, page + vma->vm_pgoff, > > - PAGE_SIZE, vma->vm_page_prot)) > > - if (remap_pfn_range(vma, addr, pfn, PAGE_SIZE, PAGE_READONLY)) > > You've removed the ability for the caller to set the pte protections - it > now always uses vma->vm_page_prot. > > please explain... They should use vma->vm_page_prot? The callers affected are the PAGE_SHARED ones (the others are unchanged). Isn't it correct to provide readonly mappings if userspace asks for it? I assumed this is why Linus went this way too with the new vm_insert_page interface. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org