From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail143.messagelabs.com (mail143.messagelabs.com [216.82.254.35]) by kanga.kvack.org (Postfix) with SMTP id C18265F0001 for ; Sun, 19 Apr 2009 21:36:31 -0400 (EDT) From: Izik Eidus Subject: [PATCH 2/5] add get_pte(): helper function: fetching pte for va Date: Mon, 20 Apr 2009 04:36:03 +0300 Message-Id: <1240191366-10029-3-git-send-email-ieidus@redhat.com> In-Reply-To: <1240191366-10029-2-git-send-email-ieidus@redhat.com> References: <1240191366-10029-1-git-send-email-ieidus@redhat.com> <1240191366-10029-2-git-send-email-ieidus@redhat.com> Sender: owner-linux-mm@kvack.org To: akpm@linux-foundation.org Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, kvm@vger.kernel.org, avi@redhat.com, aarcange@redhat.com, chrisw@redhat.com, mtosatti@redhat.com, hugh@veritas.com, Izik Eidus List-ID: get_pte() receive mm_struct of a task, and a virtual address and return the pte corresponding to it. this function return NULL in case it couldnt fetch the pte. Signed-off-by: Izik Eidus --- include/linux/mm.h | 24 ++++++++++++++++++++++++ 1 files changed, 24 insertions(+), 0 deletions(-) diff --git a/include/linux/mm.h b/include/linux/mm.h index bff1f0d..9a34109 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -894,6 +894,30 @@ int vma_wants_writenotify(struct vm_area_struct *vma); extern pte_t *get_locked_pte(struct mm_struct *mm, unsigned long addr, spinlock_t **ptl); +static inline pte_t *get_pte(struct mm_struct *mm, unsigned long addr) +{ + pgd_t *pgd; + pud_t *pud; + pmd_t *pmd; + pte_t *ptep = NULL; + + pgd = pgd_offset(mm, addr); + if (!pgd_present(*pgd)) + goto out; + + pud = pud_offset(pgd, addr); + if (!pud_present(*pud)) + goto out; + + pmd = pmd_offset(pud, addr); + if (!pmd_present(*pmd)) + goto out; + + ptep = pte_offset_map(pmd, addr); +out: + return ptep; +} + #ifdef __PAGETABLE_PUD_FOLDED static inline int __pud_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address) -- 1.5.6.5 -- 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