From patchwork Mon May 13 11:11:07 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Elias El Yandouzi X-Patchwork-Id: 13663358 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 0AA1CC25B10 for ; Mon, 13 May 2024 11:22:34 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.720865.1123902 (Exim 4.92) (envelope-from ) id 1s6TlC-0005pM-1w; Mon, 13 May 2024 11:22:26 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 720865.1123902; Mon, 13 May 2024 11:22:26 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1s6TlB-0005pF-V4; Mon, 13 May 2024 11:22:25 +0000 Received: by outflank-mailman (input) for mailman id 720865; Mon, 13 May 2024 11:22:24 +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 1s6TbD-0003MC-BJ for xen-devel@lists.xenproject.org; Mon, 13 May 2024 11:12:07 +0000 Received: from smtp-fw-80007.amazon.com (smtp-fw-80007.amazon.com [99.78.197.218]) by se1-gles-sth1.inumbo.com (Halon) with ESMTPS id a0151583-1119-11ef-909d-e314d9c70b13; Mon, 13 May 2024 13:12:04 +0200 (CEST) Received: from pdx4-co-svc-p1-lb2-vlan2.amazon.com (HELO smtpout.prod.us-east-1.prod.farcaster.email.amazon.dev) ([10.25.36.210]) by smtp-border-fw-80007.pdx80.corp.amazon.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 May 2024 11:11:48 +0000 Received: from EX19MTAUEB001.ant.amazon.com [10.0.44.209:62332] by smtpin.naws.us-east-1.prod.farcaster.email.amazon.dev [10.0.4.17:2525] with esmtp (Farcaster) id 8f2b529f-472e-4c5c-9ad3-66a0982e429a; Mon, 13 May 2024 11:11:47 +0000 (UTC) Received: from EX19D008UEA004.ant.amazon.com (10.252.134.191) by EX19MTAUEB001.ant.amazon.com (10.252.135.108) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1258.28; Mon, 13 May 2024 11:11:45 +0000 Received: from EX19MTAUWB001.ant.amazon.com (10.250.64.248) by EX19D008UEA004.ant.amazon.com (10.252.134.191) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1258.28; Mon, 13 May 2024 11:11:45 +0000 Received: from dev-dsk-eliasely-1a-fd74790f.eu-west-1.amazon.com (10.253.91.118) by mail-relay.amazon.com (10.250.64.254) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1258.28 via Frontend Transport; Mon, 13 May 2024 11:11:43 +0000 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: a0151583-1119-11ef-909d-e314d9c70b13 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.com; i=@amazon.com; q=dns/txt; s=amazon201209; t=1715598725; x=1747134725; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=Xc4KQdAGUonE6oCgkT6a8PPvVb9mrXzRPtcULUVgVPo=; b=YfknjdWUU8mqIbVuFIkpr+b9VYAflza38Z8+VTcdAJu5+DVpsjFMsvsL ecaXDbStw95jlpG24sDGhJNlvZWID6NNEV0sTW8rB31fa13yvvxlJ9eb4 NW6vzJDUiFPEf2mLW4t8Ez11B/s0XdNcZvBnDI8LdPMU78yLkGRUN2pfA 0=; X-IronPort-AV: E=Sophos;i="6.08,158,1712620800"; d="scan'208";a="295769775" X-Farcaster-Flow-ID: 8f2b529f-472e-4c5c-9ad3-66a0982e429a From: Elias El Yandouzi To: CC: , , , Hongyan Xia , Julien Grall Subject: [PATCH V3 09/19] x86/domain_page: Remove the fast paths when mfn is not in the directmap Date: Mon, 13 May 2024 11:11:07 +0000 Message-ID: <20240513111117.68828-10-eliasely@amazon.com> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20240513111117.68828-1-eliasely@amazon.com> References: <20240513111117.68828-1-eliasely@amazon.com> MIME-Version: 1.0 From: Hongyan Xia When mfn is not in direct map, never use mfn_to_virt for any mappings. We replace mfn_x(mfn) <= PFN_DOWN(__pa(HYPERVISOR_VIRT_END - 1)) with arch_mfns_in_direct_map(mfn, 1) because these two are equivalent. The extra comparison in arch_mfns_in_direct_map() looks different but because DIRECTMAP_VIRT_END is always higher, it does not make any difference. Lastly, domain_page_map_to_mfn() needs to gain to a special case for the PMAP. Signed-off-by: Hongyan Xia Signed-off-by: Julien Grall ---- Changes since Hongyan's version: * arch_mfn_in_direct_map() was renamed to arch_mfns_in_directmap() * add a special case for the PMAP in domain_page_map_to_mfn() diff --git a/xen/arch/x86/domain_page.c b/xen/arch/x86/domain_page.c index 55e337aaf7..89caefc8a2 100644 --- a/xen/arch/x86/domain_page.c +++ b/xen/arch/x86/domain_page.c @@ -14,8 +14,10 @@ #include #include #include +#include #include #include +#include #include static DEFINE_PER_CPU(struct vcpu *, override); @@ -35,10 +37,11 @@ static inline struct vcpu *mapcache_current_vcpu(void) /* * When using efi runtime page tables, we have the equivalent of the idle * domain's page tables but current may point at another domain's VCPU. - * Return NULL as though current is not properly set up yet. + * Return the idle domains's vcpu on that core because the efi per-domain + * region (where the mapcache is) is in-sync with the idle domain. */ if ( efi_rs_using_pgtables() ) - return NULL; + return idle_vcpu[smp_processor_id()]; /* * If guest_table is NULL, and we are running a paravirtualised guest, @@ -77,18 +80,24 @@ void *map_domain_page(mfn_t mfn) struct vcpu_maphash_entry *hashent; #ifdef NDEBUG - if ( mfn_x(mfn) <= PFN_DOWN(__pa(HYPERVISOR_VIRT_END - 1)) ) + if ( arch_mfns_in_directmap(mfn_x(mfn), 1) ) return mfn_to_virt(mfn_x(mfn)); #endif v = mapcache_current_vcpu(); - if ( !v ) - return mfn_to_virt(mfn_x(mfn)); + if ( !v || !v->domain->arch.mapcache.inuse ) + { + if ( arch_mfns_in_directmap(mfn_x(mfn), 1) ) + return mfn_to_virt(mfn_x(mfn)); + else + { + BUG_ON(system_state >= SYS_STATE_smp_boot); + return pmap_map(mfn); + } + } dcache = &v->domain->arch.mapcache; vcache = &v->arch.mapcache; - if ( !dcache->inuse ) - return mfn_to_virt(mfn_x(mfn)); perfc_incr(map_domain_page_count); @@ -184,6 +193,12 @@ void unmap_domain_page(const void *ptr) if ( !va || va >= DIRECTMAP_VIRT_START ) return; + if ( va >= FIXADDR_START && va < FIXADDR_TOP ) + { + pmap_unmap((void *)ptr); + return; + } + ASSERT(va >= MAPCACHE_VIRT_START && va < MAPCACHE_VIRT_END); v = mapcache_current_vcpu(); @@ -237,7 +252,7 @@ int mapcache_domain_init(struct domain *d) unsigned int bitmap_pages; #ifdef NDEBUG - if ( !mem_hotplug && max_page <= PFN_DOWN(__pa(HYPERVISOR_VIRT_END - 1)) ) + if ( !mem_hotplug && arch_mfn_in_directmap(0, max_page) ) return 0; #endif @@ -308,7 +323,7 @@ void *map_domain_page_global(mfn_t mfn) local_irq_is_enabled())); #ifdef NDEBUG - if ( mfn_x(mfn) <= PFN_DOWN(__pa(HYPERVISOR_VIRT_END - 1)) ) + if ( arch_mfn_in_directmap(mfn_x(mfn, 1)) ) return mfn_to_virt(mfn_x(mfn)); #endif @@ -335,6 +350,23 @@ mfn_t domain_page_map_to_mfn(const void *ptr) if ( va >= DIRECTMAP_VIRT_START ) return _mfn(virt_to_mfn(ptr)); + /* + * The fixmap is stealing the top-end of the VMAP. So the check for + * the PMAP *must* happen first. + * + * Also, the fixmap translate a slot to an address backwards. The + * logic will rely on it to avoid any complexity. So check at + * compile time this will always hold. + */ + BUILD_BUG_ON(fix_to_virt(FIX_PMAP_BEGIN) < fix_to_virt(FIX_PMAP_END)); + + if ( ((unsigned long)fix_to_virt(FIX_PMAP_END) <= va) && + ((va & PAGE_MASK) <= (unsigned long)fix_to_virt(FIX_PMAP_BEGIN)) ) + { + BUG_ON(system_state >= SYS_STATE_smp_boot); + return l1e_get_mfn(l1_fixmap[l1_table_offset(va)]); + } + if ( va >= VMAP_VIRT_START && va < VMAP_VIRT_END ) return vmap_to_mfn(va);