From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnd Bergmann Subject: [PATCH] asm-generic: add pgtable-nommu.h Date: Wed, 15 Jul 2009 11:25:48 +0200 Message-ID: <200907151125.49327.arnd@arndb.de> References: <4A5D8797.10004@petalogix.com> Mime-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Return-path: Received: from moutng.kundenserver.de ([212.227.17.10]:60764 "EHLO moutng.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753049AbZGOJZ5 (ORCPT ); Wed, 15 Jul 2009 05:25:57 -0400 In-Reply-To: <4A5D8797.10004@petalogix.com> Sender: linux-arch-owner@vger.kernel.org List-ID: To: michal.simek@petalogix.com Cc: Linux Kernel list , lkml All nommu architectures have almost identical pgtable.h implementations, so we should have a common file for them. I must have missed this in the earlier asm-generic submission. Signed-off-by: Arnd Bergmann --- On Wednesday 15 July 2009, Michal Simek wrote: > I found that we should simplify pgtable.h. There are a lot of generic > functions which use all archs. Have you look at it or not? I have missed this one for some reason, maybe because it looked too complicated at some point, or because it is already very complex with a lot of different helper header files. For the nommu case, it should be trivial to add something. Can you try if the patch below gives you something useful? diff --git a/include/asm-generic/pgtable-nommu.h b/include/asm-generic/pgtable-nommu.h new file mode 100644 index 0000000..c194f85 --- /dev/null +++ b/include/asm-generic/pgtable-nommu.h @@ -0,0 +1,74 @@ +#ifndef __ASM_GENERIC_PGTABLE_H +#define __ASM_GENERIC_PGTABLE_H + +#include + +#include +#include +#include + +/* + * Trivial page table functions. + */ +#define pgd_present(pgd) (1) +#define pgd_none(pgd) (0) +#define pgd_bad(pgd) (0) +#define pgd_clear(pgdp) +#define kern_addr_valid(addr) (1) +#define pmd_offset(a, b) ((void *)0) + +#define PAGE_NONE __pgprot(0) +#define PAGE_SHARED __pgprot(0) +#define PAGE_COPY __pgprot(0) +#define PAGE_READONLY __pgprot(0) +#define PAGE_KERNEL __pgprot(0) + +extern void paging_init(void); +#define swapper_pg_dir ((pgd_t *) 0) + +#define __swp_type(x) (0) +#define __swp_offset(x) (0) +#define __swp_entry(typ,off) ((swp_entry_t) { ((typ) | ((off) << 7)) }) +#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) }) +#define __swp_entry_to_pte(x) ((pte_t) { (x).val }) + +static inline int pte_file(pte_t pte) +{ + return 0; +} + +/* + * ZERO_PAGE is a global shared page that is always zero: used + * for zero-mapped memory areas etc.. + */ +#define ZERO_PAGE(vaddr) (virt_to_page(0)) + +/* + * Mark the prot value as uncacheable and unbufferable. + */ +#define pgprot_noncached(prot) __pgprot(0) +#define pgprot_writecombine(prot) __pgprot(0) + +/* + * These would be in other places but having them here reduces the diffs. + */ +extern unsigned int kobjsize(const void *objp); + +/* + * No page table caches to initialise. + */ +#define pgtable_cache_init() do { } while (0) + +#define io_remap_pfn_range(vma, vaddr, pfn, size, prot) \ + remap_pfn_range(vma, vaddr, pfn, size, prot) + +/* + * All 32bit addresses are effectively valid for vmalloc... + * Sort of meaningless for non-VM targets. + */ +#define VMALLOC_START 0 +#define VMALLOC_END 0xffffffff + +#include + +#endif /* __ASM_GENERIC_PGTABLE_H */