From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jes Sorensen Date: Fri, 17 Mar 2006 13:58:06 +0000 Subject: Re: [patch] mspec - special memory driver and do_no_pfn handler Message-Id: <441AC06E.1090909@sgi.com> List-Id: References: <441ABEDD.4070003@de.ibm.com> In-Reply-To: <441ABEDD.4070003@de.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: carsteno@de.ibm.com Cc: Andrew Morton , Linus Torvalds , linux-kernel@vger.kernel.org, linux-ia64@vger.kernel.org, Christoph Hellwig Carsten Otte wrote: > Jes Sorensen wrote: >> Index: linux-2.6/include/linux/mm.h >> =================================>> --- linux-2.6.orig/include/linux/mm.h >> +++ linux-2.6/include/linux/mm.h >> @@ -199,6 +199,7 @@ >> void (*open)(struct vm_area_struct * area); >> void (*close)(struct vm_area_struct * area); >> struct page * (*nopage)(struct vm_area_struct * area, unsigned long address, int *type); >> + long (*nopfn)(struct vm_area_struct * area, unsigned long address, int *type); >> int (*populate)(struct vm_area_struct * area, unsigned long address, unsigned long len, pgprot_t prot, unsigned long pgoff, int nonblock); >> #ifdef CONFIG_NUMA >> int (*set_policy)(struct vm_area_struct *vma, struct mempolicy *new); > If you use address as parameter to nopfn, it won't work with highmem > on 32bit systems. Alternative would be to use (unsigned long) phys. page > frame number. Hi Carsten, The address comes from handle_pte_fault() passing it to do_no_pfn() passing it to ->nopfn(), ie. it's the faulted address, not the physical one. > Your work in memory.c looks like the right thing to do. > Afaics it will work for xip as well once I figure how to > do COW. Cool stuff :-). :-) Cheers, Jes