From patchwork Wed Jan 8 20:24:39 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sean Christopherson X-Patchwork-Id: 11324599 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 0571D1871 for ; Wed, 8 Jan 2020 20:27:16 +0000 (UTC) Received: from ml01.01.org (ml01.01.org [198.145.21.10]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id E0D0020705 for ; Wed, 8 Jan 2020 20:27:15 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E0D0020705 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-nvdimm-bounces@lists.01.org Received: from ml01.vlan13.01.org (localhost [IPv6:::1]) by ml01.01.org (Postfix) with ESMTP id C63AE10097E1A; Wed, 8 Jan 2020 12:30:29 -0800 (PST) Received-SPF: Pass (mailfrom) identity=mailfrom; client-ip=134.134.136.20; helo=mga02.intel.com; envelope-from=sean.j.christopherson@intel.com; receiver= Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id C48DF10097DEE for ; Wed, 8 Jan 2020 12:30:25 -0800 (PST) X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga007.jf.intel.com ([10.7.209.58]) by orsmga101.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 08 Jan 2020 12:27:06 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.69,411,1571727600"; d="scan'208";a="211658370" Received: from sjchrist-coffee.jf.intel.com ([10.54.74.202]) by orsmga007.jf.intel.com with ESMTP; 08 Jan 2020 12:27:06 -0800 From: Sean Christopherson To: Paolo Bonzini Subject: [PATCH 05/14] x86/mm: Introduce lookup_address_in_mm() Date: Wed, 8 Jan 2020 12:24:39 -0800 Message-Id: <20200108202448.9669-6-sean.j.christopherson@intel.com> X-Mailer: git-send-email 2.24.1 In-Reply-To: <20200108202448.9669-1-sean.j.christopherson@intel.com> References: <20200108202448.9669-1-sean.j.christopherson@intel.com> MIME-Version: 1.0 Message-ID-Hash: YFMK4EVHXDYDD7MKSVXTJV4ARXZO44WW X-Message-ID-Hash: YFMK4EVHXDYDD7MKSVXTJV4ARXZO44WW X-MailFrom: sean.j.christopherson@intel.com X-Mailman-Rule-Hits: nonmember-moderation X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation CC: Paul Mackerras , Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , Dave Hansen , Andy Lutomirski , Peter Zijlstra , Andrew Morton , Marc Zyngier , James Morse , Julien Thierry , Suzuki K Poulose , kvm-ppc@vger.kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, syzbot+c9d1fb51ac9d0d10c39d@syzkaller.appspotmail.com, Andrea Arcangeli , Barret Rhoden , David Hildenbrand , Jason Zeng , Liran Alon , linux-nvdimm X-Mailman-Version: 3.1.1 Precedence: list List-Id: "Linux-nvdimm developer list." Archived-At: List-Archive: List-Help: List-Post: List-Subscribe: List-Unsubscribe: Add a helper, lookup_address_in_mm(), to traverse the page tables of a given mm struct. KVM will use the helper to retrieve the host mapping level, e.g. 4k vs. 2mb vs. 1gb, of a compound (or DAX-backed) page without having to resort to implementation specific metadata. E.g. KVM currently uses different logic for HugeTLB vs. THP, and would add a third variant for DAX-backed files. Cc: Dan Williams Signed-off-by: Sean Christopherson Reviewed-by: Thomas Gleixner --- arch/x86/include/asm/pgtable_types.h | 4 ++++ arch/x86/mm/pageattr.c | 11 +++++++++++ 2 files changed, 15 insertions(+) diff --git a/arch/x86/include/asm/pgtable_types.h b/arch/x86/include/asm/pgtable_types.h index b5e49e6bac63..400ac8da75e8 100644 --- a/arch/x86/include/asm/pgtable_types.h +++ b/arch/x86/include/asm/pgtable_types.h @@ -561,6 +561,10 @@ static inline void update_page_count(int level, unsigned long pages) { } extern pte_t *lookup_address(unsigned long address, unsigned int *level); extern pte_t *lookup_address_in_pgd(pgd_t *pgd, unsigned long address, unsigned int *level); + +struct mm_struct; +pte_t *lookup_address_in_mm(struct mm_struct *mm, unsigned long address, + unsigned int *level); extern pmd_t *lookup_pmd_address(unsigned long address); extern phys_addr_t slow_virt_to_phys(void *__address); extern int __init kernel_map_pages_in_pgd(pgd_t *pgd, u64 pfn, diff --git a/arch/x86/mm/pageattr.c b/arch/x86/mm/pageattr.c index 0d09cc5aad61..8787fec876e4 100644 --- a/arch/x86/mm/pageattr.c +++ b/arch/x86/mm/pageattr.c @@ -618,6 +618,17 @@ pte_t *lookup_address(unsigned long address, unsigned int *level) } EXPORT_SYMBOL_GPL(lookup_address); +/* + * Lookup the page table entry for a virtual address in a given mm. Return a + * pointer to the entry and the level of the mapping. + */ +pte_t *lookup_address_in_mm(struct mm_struct *mm, unsigned long address, + unsigned int *level) +{ + return lookup_address_in_pgd(pgd_offset(mm, address), address, level); +} +EXPORT_SYMBOL_GPL(lookup_address_in_mm); + static pte_t *_lookup_address_cpa(struct cpa_data *cpa, unsigned long address, unsigned int *level) {