From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id AB3D8C4332F for ; Tue, 29 Mar 2022 16:47:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239799AbiC2Qsm (ORCPT ); Tue, 29 Mar 2022 12:48:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55332 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239834AbiC2Qsk (ORCPT ); Tue, 29 Mar 2022 12:48:40 -0400 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 86D4BB53C9 for ; Tue, 29 Mar 2022 09:46:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1648572416; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=qCOLd7ScB3TWjSGdY4CbToIDZJ4hYbd0NeSKJa+Yxms=; b=PKPwqB9ZZeHLOpoxWsk5WLNVIahq8FpBaqW0azgDbW7ZX7/WrYWLDY+XdBeuG/LCrHpe+O /+o1Xbv4YEPcT4fGf1roM81/WFE/Zjk/qo3U8HQ8uYJw+lWC2hNSx/huL0BNWsm1+1UW5T 8xNZ1VabGaywFuTfMgsecdHy1bWVjdE= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-498-ujdDMkxTNKC-pLfA0LZt3w-1; Tue, 29 Mar 2022 12:46:52 -0400 X-MC-Unique: ujdDMkxTNKC-pLfA0LZt3w-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id F395D804198; Tue, 29 Mar 2022 16:46:49 +0000 (UTC) Received: from t480s.redhat.com (unknown [10.39.194.134]) by smtp.corp.redhat.com (Postfix) with ESMTP id 8487B111F3B0; Tue, 29 Mar 2022 16:46:18 +0000 (UTC) From: David Hildenbrand To: linux-kernel@vger.kernel.org Cc: Andrew Morton , Hugh Dickins , Linus Torvalds , David Rientjes , Shakeel Butt , John Hubbard , Jason Gunthorpe , Mike Kravetz , Mike Rapoport , Yang Shi , "Kirill A . Shutemov" , Matthew Wilcox , Vlastimil Babka , Jann Horn , Michal Hocko , Nadav Amit , Rik van Riel , Roman Gushchin , Andrea Arcangeli , Peter Xu , Donald Dutile , Christoph Hellwig , Oleg Nesterov , Jan Kara , Liang Zhang , Pedro Gomes , Oded Gabbay , Catalin Marinas , Will Deacon , Michael Ellerman , Benjamin Herrenschmidt , Paul Mackerras , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , Gerald Schaefer , linux-mm@kvack.org, x86@kernel.org, linux-arm-kernel@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, David Hildenbrand Subject: [PATCH v2 3/8] x86/pgtable: support __HAVE_ARCH_PTE_SWP_EXCLUSIVE Date: Tue, 29 Mar 2022 18:43:24 +0200 Message-Id: <20220329164329.208407-4-david@redhat.com> In-Reply-To: <20220329164329.208407-1-david@redhat.com> References: <20220329164329.208407-1-david@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.78 on 10.11.54.3 Precedence: bulk List-ID: X-Mailing-List: linux-s390@vger.kernel.org Let's use bit 3 to remember PG_anon_exclusive in swap ptes. Signed-off-by: David Hildenbrand --- arch/x86/include/asm/pgtable.h | 16 ++++++++++++++++ arch/x86/include/asm/pgtable_64.h | 4 +++- arch/x86/include/asm/pgtable_types.h | 5 +++++ 3 files changed, 24 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h index 62ab07e24aef..e42e668153e9 100644 --- a/arch/x86/include/asm/pgtable.h +++ b/arch/x86/include/asm/pgtable.h @@ -1292,6 +1292,22 @@ static inline void update_mmu_cache_pud(struct vm_area_struct *vma, { } +#define __HAVE_ARCH_PTE_SWP_EXCLUSIVE +static inline pte_t pte_swp_mkexclusive(pte_t pte) +{ + return pte_set_flags(pte, _PAGE_SWP_EXCLUSIVE); +} + +static inline int pte_swp_exclusive(pte_t pte) +{ + return pte_flags(pte) & _PAGE_SWP_EXCLUSIVE; +} + +static inline pte_t pte_swp_clear_exclusive(pte_t pte) +{ + return pte_clear_flags(pte, _PAGE_SWP_EXCLUSIVE); +} + #ifdef CONFIG_HAVE_ARCH_SOFT_DIRTY static inline pte_t pte_swp_mksoft_dirty(pte_t pte) { diff --git a/arch/x86/include/asm/pgtable_64.h b/arch/x86/include/asm/pgtable_64.h index 56d0399a0cd1..e479491da8d5 100644 --- a/arch/x86/include/asm/pgtable_64.h +++ b/arch/x86/include/asm/pgtable_64.h @@ -186,7 +186,7 @@ static inline void native_pgd_clear(pgd_t *pgd) * * | ... | 11| 10| 9|8|7|6|5| 4| 3|2| 1|0| <- bit number * | ... |SW3|SW2|SW1|G|L|D|A|CD|WT|U| W|P| <- bit names - * | TYPE (59-63) | ~OFFSET (9-58) |0|0|X|X| X| X|F|SD|0| <- swp entry + * | TYPE (59-63) | ~OFFSET (9-58) |0|0|X|X| X| E|F|SD|0| <- swp entry * * G (8) is aliased and used as a PROT_NONE indicator for * !present ptes. We need to start storing swap entries above @@ -203,6 +203,8 @@ static inline void native_pgd_clear(pgd_t *pgd) * F (2) in swp entry is used to record when a pagetable is * writeprotected by userfaultfd WP support. * + * E (3) in swp entry is used to rememeber PG_anon_exclusive. + * * Bit 7 in swp entry should be 0 because pmd_present checks not only P, * but also L and G. * diff --git a/arch/x86/include/asm/pgtable_types.h b/arch/x86/include/asm/pgtable_types.h index 40497a9020c6..54a8f370046d 100644 --- a/arch/x86/include/asm/pgtable_types.h +++ b/arch/x86/include/asm/pgtable_types.h @@ -83,6 +83,11 @@ #define _PAGE_SOFT_DIRTY (_AT(pteval_t, 0)) #endif +/* + * We borrow bit 3 to remember PG_anon_exclusive. + */ +#define _PAGE_SWP_EXCLUSIVE _PAGE_PWT + /* * Tracking soft dirty bit when a page goes to a swap is tricky. * We need a bit which can be stored in pte _and_ not conflict -- 2.35.1