From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <491C61B1.10005@goop.org> Date: Thu, 13 Nov 2008 09:19:45 -0800 From: Jeremy Fitzhardinge MIME-Version: 1.0 Subject: [PATCH 1/2] mm: implement remap_pfn_range with apply_to_page_range Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Andrew Morton Cc: Nick Piggin , Linux Memory Management List , Linux Kernel Mailing List , "Pallipadi, Venkatesh" List-ID: remap_pte_range() just wants to apply a function over a range of ptes corresponding to a virtual address range. That's exactly what apply_to_page_range() does, so use it. Signed-off-by: Jeremy Fitzhardinge --- mm/memory.c | 92 ++++++++++++----------------------------------------------- 1 file changed, 20 insertions(+), 72 deletions(-) =================================================================== --- a/mm/memory.c +++ b/mm/memory.c @@ -1472,69 +1472,20 @@ } EXPORT_SYMBOL(vm_insert_mixed); -/* - * maps a range of physical memory into the requested pages. the old - * mappings are removed. any references to nonexistent pages results - * in null mappings (currently treated as "copy-on-access") - */ -static int remap_pte_range(struct mm_struct *mm, pmd_t *pmd, - unsigned long addr, unsigned long end, - unsigned long pfn, pgprot_t prot) +struct remap_data { + struct mm_struct *mm; + unsigned long pfn; + pgprot_t prot; +}; + +static int remap_area_pte_fn(pte_t *ptep, pgtable_t token, + unsigned long addr, void *data) { - pte_t *pte; - spinlock_t *ptl; + struct remap_data *rmd = data; + pte_t pte = pte_mkspecial(pfn_pte(rmd->pfn++, rmd->prot)); - pte = pte_alloc_map_lock(mm, pmd, addr, &ptl); - if (!pte) - return -ENOMEM; - arch_enter_lazy_mmu_mode(); - do { - BUG_ON(!pte_none(*pte)); - set_pte_at(mm, addr, pte, pte_mkspecial(pfn_pte(pfn, prot))); - pfn++; - } while (pte++, addr += PAGE_SIZE, addr != end); - arch_leave_lazy_mmu_mode(); - pte_unmap_unlock(pte - 1, ptl); - return 0; -} + set_pte_at(rmd->mm, addr, ptep, pte); -static inline int remap_pmd_range(struct mm_struct *mm, pud_t *pud, - unsigned long addr, unsigned long end, - unsigned long pfn, pgprot_t prot) -{ - pmd_t *pmd; - unsigned long next; - - pfn -= addr >> PAGE_SHIFT; - pmd = pmd_alloc(mm, pud, addr); - if (!pmd) - return -ENOMEM; - do { - next = pmd_addr_end(addr, end); - if (remap_pte_range(mm, pmd, addr, next, - pfn + (addr >> PAGE_SHIFT), prot)) - return -ENOMEM; - } while (pmd++, addr = next, addr != end); - return 0; -} - -static inline int remap_pud_range(struct mm_struct *mm, pgd_t *pgd, - unsigned long addr, unsigned long end, - unsigned long pfn, pgprot_t prot) -{ - pud_t *pud; - unsigned long next; - - pfn -= addr >> PAGE_SHIFT; - pud = pud_alloc(mm, pgd, addr); - if (!pud) - return -ENOMEM; - do { - next = pud_addr_end(addr, end); - if (remap_pmd_range(mm, pud, addr, next, - pfn + (addr >> PAGE_SHIFT), prot)) - return -ENOMEM; - } while (pud++, addr = next, addr != end); return 0; } @@ -1551,10 +1502,9 @@ int remap_pfn_range(struct vm_area_struct *vma, unsigned long addr, unsigned long pfn, unsigned long size, pgprot_t prot) { - pgd_t *pgd; - unsigned long next; unsigned long end = addr + PAGE_ALIGN(size); struct mm_struct *mm = vma->vm_mm; + struct remap_data rmd; int err; /* @@ -1584,16 +1534,14 @@ vma->vm_flags |= VM_IO | VM_RESERVED | VM_PFNMAP; BUG_ON(addr >= end); - pfn -= addr >> PAGE_SHIFT; - pgd = pgd_offset(mm, addr); - flush_cache_range(vma, addr, end); - do { - next = pgd_addr_end(addr, end); - err = remap_pud_range(mm, pgd, addr, next, - pfn + (addr >> PAGE_SHIFT), prot); - if (err) - break; - } while (pgd++, addr = next, addr != end); + + rmd.mm = mm; + rmd.pfn = pfn; + rmd.prot = prot; + + err = apply_to_page_range(mm, addr, end - addr, + remap_area_pte_fn, &rmd); + return err; } EXPORT_SYMBOL(remap_pfn_range); -- 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