From patchwork Sun Apr 2 12:24:26 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yu Zhang X-Patchwork-Id: 9658451 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id B3A21602BA for ; Sun, 2 Apr 2017 12:46:32 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 92E962835B for ; Sun, 2 Apr 2017 12:46:32 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 878EA284A5; Sun, 2 Apr 2017 12:46:32 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.1 required=2.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_MED,T_DKIM_INVALID autolearn=ham version=3.3.1 Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id D01C12835B for ; Sun, 2 Apr 2017 12:46:31 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.84_2) (envelope-from ) id 1cuerl-0003Cg-GO; Sun, 02 Apr 2017 12:44:21 +0000 Received: from mail6.bemta3.messagelabs.com ([195.245.230.39]) by lists.xenproject.org with esmtp (Exim 4.84_2) (envelope-from ) id 1cuerk-0003C3-Mw for xen-devel@lists.xen.org; Sun, 02 Apr 2017 12:44:20 +0000 Received: from [85.158.137.68] by server-2.bemta-3.messagelabs.com id E4/B7-01903-322F0E85; Sun, 02 Apr 2017 12:44:19 +0000 X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFvrDLMWRWlGSWpSXmKPExsXS1tYhoav86UG EweMT7BZLPi5mcWD0OLr7N1MAYxRrZl5SfkUCa0b74QfsBacDK45PvMPewPjWpouRi4NF4BaT xJJzk5hAHCGBaYwSOy49Z+li5OSQEOCVOLJsBiuE7Sdx/sNCFoiidkaJE7NnsoMk2AS0JX6s/ s0IYosISEtc+3yZEaSIWaCTSeLk1stsIAlhgVSJRxvegDWwCKhK7H8zESzOK+AhcfLVV6gNch Inj00GszkFPCWeLt8AZgsB1ez4v5h9AiPfAkaGVYzqxalFZalFuuZ6SUWZ6RkluYmZObqGBsZ 6uanFxYnpqTmJScV6yfm5mxiBocIABDsYG787HWKU5GBSEuX9XnwvQogvKT+lMiOxOCO+qDQn tfgQowwHh5IEL9fHBxFCgkWp6akVaZk5wKCFSUtw8CiJ8KqApHmLCxJzizPTIVKnGBWlxHmZQ BICIImM0jy4NlikXGKUlRLmZQQ6RIinILUoN7MEVf4VozgHo5IwrwPIFJ7MvBK46a+AFjMBLb b4ehdkcUkiQkqqgbHJcdrChc1bWjtY/eLZb/Bemywgm/vnlc26qC0q7nFKTfuqGoJ+Gy1bcq7 yv/PKG11XH13py/nI89i+yt54plnPU57qf/3GmssfiinP3FJYarnGZH5gQN7fo7MPG0hUbTE5 vGT9PiaLVX9v/ph+5JTyrjfnnHYv+9zs1PH67U8XJcO8S/sD/4UrsRRnJBpqMRcVJwIA978sX o8CAAA= X-Env-Sender: yu.c.zhang@linux.intel.com X-Msg-Ref: server-8.tower-31.messagelabs.com!1491137056!93641809!1 X-Originating-IP: [134.134.136.24] X-SpamReason: No, hits=0.0 required=7.0 tests=sa_preprocessor: VHJ1c3RlZCBJUDogMTM0LjEzNC4xMzYuMjQgPT4gMzkwOTcx\n X-StarScan-Received: X-StarScan-Version: 9.2.3; banners=-,-,- X-VirusChecked: Checked Received: (qmail 55273 invoked from network); 2 Apr 2017 12:44:18 -0000 Received: from mga09.intel.com (HELO mga09.intel.com) (134.134.136.24) by server-8.tower-31.messagelabs.com with DHE-RSA-AES256-GCM-SHA384 encrypted SMTP; 2 Apr 2017 12:44:18 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=intel.com; i=@intel.com; q=dns/txt; s=intel; t=1491137058; x=1522673058; h=from:to:cc:subject:date:message-id:in-reply-to: references; bh=ue30uJtPQZ1xCr5+kxTau/Vrj3PceT+G+0rU9glvGyY=; b=As/okYMn7QEGsgbVObckaCbCKdOCvMARd0m4sUyfV6JagRl8XA8bbqte rei9+2DG2mgSjmnk5hoxDKBXFBre+Q==; Received: from orsmga005.jf.intel.com ([10.7.209.41]) by orsmga102.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 02 Apr 2017 05:44:16 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.36,263,1486454400"; d="scan'208";a="81958958" Received: from zhangyu-optiplex-9020.bj.intel.com ([10.238.135.159]) by orsmga005.jf.intel.com with ESMTP; 02 Apr 2017 05:44:14 -0700 From: Yu Zhang To: xen-devel@lists.xen.org Date: Sun, 2 Apr 2017 20:24:26 +0800 Message-Id: <1491135867-623-6-git-send-email-yu.c.zhang@linux.intel.com> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1491135867-623-1-git-send-email-yu.c.zhang@linux.intel.com> References: <1491135867-623-1-git-send-email-yu.c.zhang@linux.intel.com> Cc: Kevin Tian , Jun Nakajima , George Dunlap , Andrew Cooper , Paul Durrant , zhiyuan.lv@intel.com, Jan Beulich Subject: [Xen-devel] [PATCH v10 5/6] x86/ioreq server: Asynchronously reset outstanding p2m_ioreq_server entries. X-BeenThere: xen-devel@lists.xen.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: xen-devel-bounces@lists.xen.org Sender: "Xen-devel" X-Virus-Scanned: ClamAV using ClamSMTP After an ioreq server has unmapped, the remaining p2m_ioreq_server entries need to be reset back to p2m_ram_rw. This patch does this asynchronously with the current p2m_change_entry_type_global() interface. New field entry_count is introduced in struct p2m_domain, to record the number of p2m_ioreq_server p2m page table entries. One nature of these entries is that they only point to 4K sized page frames, because all p2m_ioreq_server entries are originated from p2m_ram_rw ones in p2m_change_type_one(). We do not need to worry about the counting for 2M/1G sized pages. This patch disallows mapping of an ioreq server, when there's still p2m_ioreq_server entry left, in case another mapping occurs right after the current one being unmapped, releases its lock, with p2m table not synced yet. This patch also disallows live migration, when there's remaining p2m_ioreq_server entry in p2m table. The core reason is our current implementation of p2m_change_entry_type_global() lacks information to resync p2m_ioreq_server entries correctly if global_logdirty is on. Signed-off-by: Yu Zhang Reviewed-by: Paul Durrant Reviewed-by: Jan Beulich --- Cc: Paul Durrant Cc: Jan Beulich Cc: Andrew Cooper Cc: George Dunlap Cc: Jun Nakajima Cc: Kevin Tian changes in v5: - According to comments from Jan: use unsigned long for entry_count; - According to comments from Jan: refuse mapping requirement when there's p2m_ioreq_server remained in p2m table. - Added "Reviewed-by: Paul Durrant " changes in v4: - According to comments from Jan: use ASSERT() instead of 'if' condition in p2m_change_type_one(). - According to comments from Jan: commit message changes to mention the p2m_ioreq_server are all based on 4K sized pages. changes in v3: - Move the synchronously resetting logic into patch 5. - According to comments from Jan: introduce p2m_check_changeable() to clarify the p2m type change code. - According to comments from George: use locks in the same order to avoid deadlock, call p2m_change_entry_type_global() after unmap of the ioreq server is finished. changes in v2: - Move the calculation of ioreq server page entry_cout into p2m_change_type_one() so that we do not need a seperate lock. Note: entry_count is also calculated in resolve_misconfig()/ do_recalc(), fortunately callers of both routines have p2m lock protected already. - Simplify logic in hvmop_set_mem_type(). - Introduce routine p2m_finish_type_change() to walk the p2m table and do the p2m reset. --- xen/arch/x86/hvm/ioreq.c | 8 ++++++++ xen/arch/x86/mm/hap/hap.c | 9 +++++++++ xen/arch/x86/mm/p2m-ept.c | 8 +++++++- xen/arch/x86/mm/p2m-pt.c | 13 +++++++++++-- xen/arch/x86/mm/p2m.c | 29 +++++++++++++++++++++++++++++ xen/include/asm-x86/p2m.h | 9 ++++++++- 6 files changed, 72 insertions(+), 4 deletions(-) diff --git a/xen/arch/x86/hvm/ioreq.c b/xen/arch/x86/hvm/ioreq.c index 5bf3b6d..07a6c26 100644 --- a/xen/arch/x86/hvm/ioreq.c +++ b/xen/arch/x86/hvm/ioreq.c @@ -955,6 +955,14 @@ int hvm_map_mem_type_to_ioreq_server(struct domain *d, ioservid_t id, spin_unlock_recursive(&d->arch.hvm_domain.ioreq_server.lock); + if ( rc == 0 && flags == 0 ) + { + struct p2m_domain *p2m = p2m_get_hostp2m(d); + + if ( read_atomic(&p2m->ioreq.entry_count) ) + p2m_change_entry_type_global(d, p2m_ioreq_server, p2m_ram_rw); + } + return rc; } diff --git a/xen/arch/x86/mm/hap/hap.c b/xen/arch/x86/mm/hap/hap.c index a57b385..6ec950a 100644 --- a/xen/arch/x86/mm/hap/hap.c +++ b/xen/arch/x86/mm/hap/hap.c @@ -187,6 +187,15 @@ out: */ static int hap_enable_log_dirty(struct domain *d, bool_t log_global) { + struct p2m_domain *p2m = p2m_get_hostp2m(d); + + /* + * Refuse to turn on global log-dirty mode if + * there's outstanding p2m_ioreq_server pages. + */ + if ( log_global && read_atomic(&p2m->ioreq.entry_count) ) + return -EBUSY; + /* turn on PG_log_dirty bit in paging mode */ paging_lock(d); d->arch.paging.mode |= PG_log_dirty; diff --git a/xen/arch/x86/mm/p2m-ept.c b/xen/arch/x86/mm/p2m-ept.c index cc1eb21..62e9ddf 100644 --- a/xen/arch/x86/mm/p2m-ept.c +++ b/xen/arch/x86/mm/p2m-ept.c @@ -544,6 +544,12 @@ static int resolve_misconfig(struct p2m_domain *p2m, unsigned long gfn) e.ipat = ipat; if ( e.recalc && p2m_is_changeable(e.sa_p2mt) ) { + if ( e.sa_p2mt == p2m_ioreq_server ) + { + ASSERT(p2m->ioreq.entry_count > 0); + p2m->ioreq.entry_count--; + } + e.sa_p2mt = p2m_is_logdirty_range(p2m, gfn + i, gfn + i) ? p2m_ram_logdirty : p2m_ram_rw; ept_p2m_type_to_flags(p2m, &e, e.sa_p2mt, e.access); @@ -965,7 +971,7 @@ static mfn_t ept_get_entry(struct p2m_domain *p2m, if ( is_epte_valid(ept_entry) ) { if ( (recalc || ept_entry->recalc) && - p2m_is_changeable(ept_entry->sa_p2mt) ) + p2m_check_changeable(ept_entry->sa_p2mt) ) *t = p2m_is_logdirty_range(p2m, gfn, gfn) ? p2m_ram_logdirty : p2m_ram_rw; else diff --git a/xen/arch/x86/mm/p2m-pt.c b/xen/arch/x86/mm/p2m-pt.c index c0055f3..0a70dc5 100644 --- a/xen/arch/x86/mm/p2m-pt.c +++ b/xen/arch/x86/mm/p2m-pt.c @@ -436,11 +436,13 @@ static int do_recalc(struct p2m_domain *p2m, unsigned long gfn) needs_recalc(l1, *pent) ) { l1_pgentry_t e = *pent; + p2m_type_t p2mt_old; if ( !valid_recalc(l1, e) ) P2M_DEBUG("bogus recalc leaf at d%d:%lx:%u\n", p2m->domain->domain_id, gfn, level); - if ( p2m_is_changeable(p2m_flags_to_type(l1e_get_flags(e))) ) + p2mt_old = p2m_flags_to_type(l1e_get_flags(e)); + if ( p2m_is_changeable(p2mt_old) ) { unsigned long mask = ~0UL << (level * PAGETABLE_ORDER); p2m_type_t p2mt = p2m_is_logdirty_range(p2m, gfn & mask, gfn | ~mask) @@ -460,6 +462,13 @@ static int do_recalc(struct p2m_domain *p2m, unsigned long gfn) mfn &= ~((unsigned long)_PAGE_PSE_PAT >> PAGE_SHIFT); flags |= _PAGE_PSE; } + + if ( p2mt_old == p2m_ioreq_server ) + { + ASSERT(p2m->ioreq.entry_count > 0); + p2m->ioreq.entry_count--; + } + e = l1e_from_pfn(mfn, flags); p2m_add_iommu_flags(&e, level, (p2mt == p2m_ram_rw) @@ -729,7 +738,7 @@ p2m_pt_set_entry(struct p2m_domain *p2m, unsigned long gfn, mfn_t mfn, static inline p2m_type_t recalc_type(bool_t recalc, p2m_type_t t, struct p2m_domain *p2m, unsigned long gfn) { - if ( !recalc || !p2m_is_changeable(t) ) + if ( !recalc || !p2m_check_changeable(t) ) return t; return p2m_is_logdirty_range(p2m, gfn, gfn) ? p2m_ram_logdirty : p2m_ram_rw; diff --git a/xen/arch/x86/mm/p2m.c b/xen/arch/x86/mm/p2m.c index b84add0..7a1bdd8 100644 --- a/xen/arch/x86/mm/p2m.c +++ b/xen/arch/x86/mm/p2m.c @@ -317,6 +317,15 @@ int p2m_set_ioreq_server(struct domain *d, if ( p2m->ioreq.server != NULL ) goto out; + /* + * It is possible that an ioreq server has just been unmapped, + * released the spin lock, with some p2m_ioreq_server entries + * in p2m table remained. We shall refuse another ioreq server + * mapping request in such case. + */ + if ( read_atomic(&p2m->ioreq.entry_count) ) + goto out; + p2m->ioreq.server = s; p2m->ioreq.flags = flags; } @@ -938,6 +947,26 @@ int p2m_change_type_one(struct domain *d, unsigned long gfn, p2m->default_access) : -EBUSY; + if ( !rc ) + { + switch ( nt ) + { + case p2m_ram_rw: + if ( ot == p2m_ioreq_server ) + { + ASSERT(p2m->ioreq.entry_count > 0); + p2m->ioreq.entry_count--; + } + break; + case p2m_ioreq_server: + ASSERT(ot == p2m_ram_rw); + p2m->ioreq.entry_count++; + break; + default: + break; + } + } + gfn_unlock(p2m, gfn, 0); return rc; diff --git a/xen/include/asm-x86/p2m.h b/xen/include/asm-x86/p2m.h index 4521620..e7e390d 100644 --- a/xen/include/asm-x86/p2m.h +++ b/xen/include/asm-x86/p2m.h @@ -120,7 +120,10 @@ typedef unsigned int p2m_query_t; /* Types that can be subject to bulk transitions. */ #define P2M_CHANGEABLE_TYPES (p2m_to_mask(p2m_ram_rw) \ - | p2m_to_mask(p2m_ram_logdirty) ) + | p2m_to_mask(p2m_ram_logdirty) \ + | p2m_to_mask(p2m_ioreq_server) ) + +#define P2M_IOREQ_TYPES (p2m_to_mask(p2m_ioreq_server)) #define P2M_POD_TYPES (p2m_to_mask(p2m_populate_on_demand)) @@ -157,6 +160,7 @@ typedef unsigned int p2m_query_t; #define p2m_is_readonly(_t) (p2m_to_mask(_t) & P2M_RO_TYPES) #define p2m_is_discard_write(_t) (p2m_to_mask(_t) & P2M_DISCARD_WRITE_TYPES) #define p2m_is_changeable(_t) (p2m_to_mask(_t) & P2M_CHANGEABLE_TYPES) +#define p2m_is_ioreq(_t) (p2m_to_mask(_t) & P2M_IOREQ_TYPES) #define p2m_is_pod(_t) (p2m_to_mask(_t) & P2M_POD_TYPES) #define p2m_is_grant(_t) (p2m_to_mask(_t) & P2M_GRANT_TYPES) /* Grant types are *not* considered valid, because they can be @@ -178,6 +182,8 @@ typedef unsigned int p2m_query_t; #define p2m_allows_invalid_mfn(t) (p2m_to_mask(t) & P2M_INVALID_MFN_TYPES) +#define p2m_check_changeable(t) (p2m_is_changeable(t) && !p2m_is_ioreq(t)) + typedef enum { p2m_host, p2m_nested, @@ -349,6 +355,7 @@ struct p2m_domain { * are to be emulated by an ioreq server. */ unsigned int flags; + unsigned long entry_count; } ioreq; };