From patchwork Thu Oct 24 09:37:05 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steven Price X-Patchwork-Id: 11208719 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 A36CB112C for ; Thu, 24 Oct 2019 09:41:30 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 80FA32166E for ; Thu, 24 Oct 2019 09:41:30 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="UT+J5Sf6" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 80FA32166E Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=+cV3ync/3gkAjk4Qzt51IiKPZ6NK2+U14TaSorOOQgU=; b=UT+J5Sf66QSEWw rUaKphj94AG2ZpjgyJmhb4mGePeKNm64CFvaKgHAsv893rBCaDqnSopTyrzBH1mhsXGZXXaB7j3H/ OyTi0e8/iR0/JD1aKgMloAhbPxSylQC6SuhqbqSGrK28/kgu/4jXzzr5tF9OznL+6QY19+gpDpXbl h/lYK0UXB2+OODipz8v77qw3K0tPJALr/ZgYnSbDHp+40AWDnVDUzh5w2bHW4cC1A6IUdEfpmztCF +yyfxSPg2EXWzJeRw/YcQrzAeFhZsoatU7XR9MakhmJ70Ni1+Iyi6liKrscosiDB5EJ4vjyy0MBkZ OwvgjRnyOXTF0mbNLDbw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1iNZcU-0005PZ-Kw; Thu, 24 Oct 2019 09:41:26 +0000 Received: from [217.140.110.172] (helo=foss.arm.com) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1iNZZG-0001Jo-DL for linux-arm-kernel@lists.infradead.org; Thu, 24 Oct 2019 09:38:10 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 5E3FA64F; Thu, 24 Oct 2019 02:38:01 -0700 (PDT) Received: from e112269-lin.cambridge.arm.com (e112269-lin.cambridge.arm.com [10.1.194.43]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id C5DB93F71F; Thu, 24 Oct 2019 02:37:58 -0700 (PDT) From: Steven Price To: linux-mm@kvack.org Subject: [PATCH v13 11/22] mm: pagewalk: Add p4d_entry() and pgd_entry() Date: Thu, 24 Oct 2019 10:37:05 +0100 Message-Id: <20191024093716.49420-12-steven.price@arm.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191024093716.49420-1-steven.price@arm.com> References: <20191024093716.49420-1-steven.price@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20191024_023806_700889_E7630555 X-CRM114-Status: GOOD ( 14.96 ) X-Spam-Score: 1.3 (+) X-Spam-Report: SpamAssassin version 3.4.2 on bombadil.infradead.org summary: Content analysis details: (1.3 points) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 SPF_PASS SPF: sender matches SPF record 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record 1.3 RDNS_NONE Delivered to internal network by a host with no rDNS X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , x86@kernel.org, Arnd Bergmann , Ard Biesheuvel , Peter Zijlstra , Catalin Marinas , Dave Hansen , linux-kernel@vger.kernel.org, Steven Price , =?utf-8?b?SsOpcsO0bWUgR2xpc3Nl?= , Ingo Molnar , Borislav Petkov , Andy Lutomirski , "H. Peter Anvin" , James Morse , Thomas Gleixner , Will Deacon , Andrew Morton , linux-arm-kernel@lists.infradead.org, "Liang, Kan" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org pgd_entry() and pud_entry() were removed by commit 0b1fbfe50006c410 ("mm/pagewalk: remove pgd_entry() and pud_entry()") because there were no users. We're about to add users so reintroduce them, along with p4d_entry() as we now have 5 levels of tables. Note that commit a00cc7d9dd93d66a ("mm, x86: add support for PUD-sized transparent hugepages") already re-added pud_entry() but with different semantics to the other callbacks. Since there have never been upstream users of this, revert the semantics back to match the other callbacks. This means pud_entry() is called for all entries, not just transparent huge pages. Signed-off-by: Steven Price --- include/linux/pagewalk.h | 19 +++++++++++++------ mm/pagewalk.c | 27 ++++++++++++++++----------- 2 files changed, 29 insertions(+), 17 deletions(-) diff --git a/include/linux/pagewalk.h b/include/linux/pagewalk.h index bddd9759bab9..12004b097eae 100644 --- a/include/linux/pagewalk.h +++ b/include/linux/pagewalk.h @@ -8,15 +8,15 @@ struct mm_walk; /** * mm_walk_ops - callbacks for walk_page_range - * @pud_entry: if set, called for each non-empty PUD (2nd-level) entry - * this handler should only handle pud_trans_huge() puds. - * the pmd_entry or pte_entry callbacks will be used for - * regular PUDs. - * @pmd_entry: if set, called for each non-empty PMD (3rd-level) entry + * @pgd_entry: if set, called for each non-empty PGD (top-level) entry + * @p4d_entry: if set, called for each non-empty P4D entry + * @pud_entry: if set, called for each non-empty PUD entry + * @pmd_entry: if set, called for each non-empty PMD entry * this handler is required to be able to handle * pmd_trans_huge() pmds. They may simply choose to * split_huge_page() instead of handling it explicitly. - * @pte_entry: if set, called for each non-empty PTE (4th-level) entry + * @pte_entry: if set, called for each non-empty PTE (lowest-level) + * entry * @pte_hole: if set, called for each hole at all levels * @hugetlb_entry: if set, called for each hugetlb entry * @test_walk: caller specific callback function to determine whether @@ -24,8 +24,15 @@ struct mm_walk; * "do page table walk over the current vma", returning * a negative value means "abort current page table walk * right now" and returning 1 means "skip the current vma" + * + * p?d_entry callbacks are called even if those levels are folded on a + * particular architecture/configuration. */ struct mm_walk_ops { + int (*pgd_entry)(pgd_t *pgd, unsigned long addr, + unsigned long next, struct mm_walk *walk); + int (*p4d_entry)(p4d_t *p4d, unsigned long addr, + unsigned long next, struct mm_walk *walk); int (*pud_entry)(pud_t *pud, unsigned long addr, unsigned long next, struct mm_walk *walk); int (*pmd_entry)(pmd_t *pmd, unsigned long addr, diff --git a/mm/pagewalk.c b/mm/pagewalk.c index d48c2a986ea3..fc4d98a3a5a0 100644 --- a/mm/pagewalk.c +++ b/mm/pagewalk.c @@ -93,15 +93,9 @@ static int walk_pud_range(p4d_t *p4d, unsigned long addr, unsigned long end, } if (ops->pud_entry) { - spinlock_t *ptl = pud_trans_huge_lock(pud, walk->vma); - - if (ptl) { - err = ops->pud_entry(pud, addr, next, walk); - spin_unlock(ptl); - if (err) - break; - continue; - } + err = ops->pud_entry(pud, addr, next, walk); + if (err) + break; } split_huge_pud(walk->vma, pud, addr); @@ -135,7 +129,12 @@ static int walk_p4d_range(pgd_t *pgd, unsigned long addr, unsigned long end, break; continue; } - if (ops->pmd_entry || ops->pte_entry) + if (ops->p4d_entry) { + err = ops->p4d_entry(p4d, addr, next, walk); + if (err) + break; + } + if (ops->pud_entry || ops->pmd_entry || ops->pte_entry) err = walk_pud_range(p4d, addr, next, walk); if (err) break; @@ -162,7 +161,13 @@ static int walk_pgd_range(unsigned long addr, unsigned long end, break; continue; } - if (ops->pmd_entry || ops->pte_entry) + if (ops->pgd_entry) { + err = ops->pgd_entry(pgd, addr, next, walk); + if (err) + break; + } + if (ops->p4d_entry || ops->pud_entry || ops->pmd_entry || + ops->pte_entry) err = walk_p4d_range(pgd, addr, next, walk); if (err) break;