From patchwork Tue Apr 23 08:25:28 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luca Fancellu X-Patchwork-Id: 13639600 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 lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id E7277C18E72 for ; Tue, 23 Apr 2024 08:26:02 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.710383.1109582 (Exim 4.92) (envelope-from ) id 1rzBTK-0002rC-5u; Tue, 23 Apr 2024 08:25:50 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 710383.1109582; Tue, 23 Apr 2024 08:25:50 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1rzBTJ-0002pb-Ov; Tue, 23 Apr 2024 08:25:49 +0000 Received: by outflank-mailman (input) for mailman id 710383; Tue, 23 Apr 2024 08:25:48 +0000 Received: from se1-gles-sth1-in.inumbo.com ([159.253.27.254] helo=se1-gles-sth1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1rzBTI-0002VX-IM for xen-devel@lists.xenproject.org; Tue, 23 Apr 2024 08:25:48 +0000 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by se1-gles-sth1.inumbo.com (Halon) with ESMTP id 1599ce26-014b-11ef-909a-e314d9c70b13; Tue, 23 Apr 2024 10:25:47 +0200 (CEST) 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 81E391477; Tue, 23 Apr 2024 01:26:14 -0700 (PDT) Received: from e125770.cambridge.arm.com (e125770.arm.com [10.1.199.43]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 68BC23F64C; Tue, 23 Apr 2024 01:25:45 -0700 (PDT) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 1599ce26-014b-11ef-909a-e314d9c70b13 From: Luca Fancellu To: xen-devel@lists.xenproject.org Cc: Penny Zheng , Stefano Stabellini , Julien Grall , Bertrand Marquis , Michal Orzel , Volodymyr Babchuk , Penny Zheng Subject: [PATCH 3/7] xen/p2m: put reference for superpage Date: Tue, 23 Apr 2024 09:25:28 +0100 Message-Id: <20240423082532.776623-4-luca.fancellu@arm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20240423082532.776623-1-luca.fancellu@arm.com> References: <20240423082532.776623-1-luca.fancellu@arm.com> MIME-Version: 1.0 From: Penny Zheng We are doing foreign memory mapping for static shared memory, and there is a great possibility that it could be super mapped. But today, p2m_put_l3_page could not handle superpages. This commits implements a new function p2m_put_superpage to handle superpages, specifically for helping put extra references for foreign superpages. Signed-off-by: Penny Zheng Signed-off-by: Luca Fancellu --- v1: - patch from https://patchwork.kernel.org/project/xen-devel/patch/20231206090623.1932275-9-Penny.Zheng@arm.com/ --- xen/arch/arm/mmu/p2m.c | 58 +++++++++++++++++++++++++++++++----------- 1 file changed, 43 insertions(+), 15 deletions(-) diff --git a/xen/arch/arm/mmu/p2m.c b/xen/arch/arm/mmu/p2m.c index 41fcca011cf4..479a80fbd4cf 100644 --- a/xen/arch/arm/mmu/p2m.c +++ b/xen/arch/arm/mmu/p2m.c @@ -753,17 +753,9 @@ static int p2m_mem_access_radix_set(struct p2m_domain *p2m, gfn_t gfn, return rc; } -/* - * Put any references on the single 4K page referenced by pte. - * TODO: Handle superpages, for now we only take special references for leaf - * pages (specifically foreign ones, which can't be super mapped today). - */ -static void p2m_put_l3_page(const lpae_t pte) +/* Put any references on the single 4K page referenced by mfn. */ +static void p2m_put_l3_page(mfn_t mfn, unsigned type) { - mfn_t mfn = lpae_get_mfn(pte); - - ASSERT(p2m_is_valid(pte)); - /* * TODO: Handle other p2m types * @@ -771,16 +763,53 @@ static void p2m_put_l3_page(const lpae_t pte) * flush the TLBs if the page is reallocated before the end of * this loop. */ - if ( p2m_is_foreign(pte.p2m.type) ) + if ( p2m_is_foreign(type) ) { ASSERT(mfn_valid(mfn)); put_page(mfn_to_page(mfn)); } /* Detect the xenheap page and mark the stored GFN as invalid. */ - else if ( p2m_is_ram(pte.p2m.type) && is_xen_heap_mfn(mfn) ) + else if ( p2m_is_ram(type) && is_xen_heap_mfn(mfn) ) page_set_xenheap_gfn(mfn_to_page(mfn), INVALID_GFN); } +/* Put any references on the superpage referenced by mfn. */ +static void p2m_put_superpage(mfn_t mfn, unsigned int next_level, unsigned type) +{ + unsigned int i; + unsigned int level_order = XEN_PT_LEVEL_ORDER(next_level); + + for ( i = 0; i < XEN_PT_LPAE_ENTRIES; i++ ) + { + if ( next_level == 3 ) + p2m_put_l3_page(mfn, type); + else + p2m_put_superpage(mfn, next_level + 1, type); + + mfn = mfn_add(mfn, 1 << level_order); + } +} + +/* Put any references on the page referenced by pte. */ +static void p2m_put_page(const lpae_t pte, unsigned int level) +{ + mfn_t mfn = lpae_get_mfn(pte); + + ASSERT(p2m_is_valid(pte)); + + /* + * We are either having a first level 1G superpage or a + * second level 2M superpage. + */ + if ( p2m_is_superpage(pte, level) ) + return p2m_put_superpage(mfn, level + 1, pte.p2m.type); + else + { + ASSERT(level == 3); + return p2m_put_l3_page(mfn, pte.p2m.type); + } +} + /* Free lpae sub-tree behind an entry */ static void p2m_free_entry(struct p2m_domain *p2m, lpae_t entry, unsigned int level) @@ -809,9 +838,8 @@ static void p2m_free_entry(struct p2m_domain *p2m, #endif p2m->stats.mappings[level]--; - /* Nothing to do if the entry is a super-page. */ - if ( level == 3 ) - p2m_put_l3_page(entry); + p2m_put_page(entry, level); + return; }