From patchwork Tue Oct 25 15:13:40 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chao Peng X-Patchwork-Id: 13019445 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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id A876CFA3743 for ; Tue, 25 Oct 2022 15:19:13 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 45C6D8E0007; Tue, 25 Oct 2022 11:19:13 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 40C138E0001; Tue, 25 Oct 2022 11:19:13 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 2AD888E0007; Tue, 25 Oct 2022 11:19:13 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id 1A21E8E0001 for ; Tue, 25 Oct 2022 11:19:13 -0400 (EDT) Received: from smtpin16.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay06.hostedemail.com (Postfix) with ESMTP id B9D9BAB35F for ; Tue, 25 Oct 2022 15:19:12 +0000 (UTC) X-FDA: 80059830144.16.87B47B3 Received: from mga06.intel.com (mga06b.intel.com [134.134.136.31]) by imf25.hostedemail.com (Postfix) with ESMTP id A11A2A0003 for ; Tue, 25 Oct 2022 15:19:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1666711151; x=1698247151; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=6EFuXYDl0hDb29a8QD5wsl2s9EmZqV7kVnmmwCD6iGo=; b=YXqGQ3WXvdzEJgoxrDj6djhtNAAC0tOzafZDRrgFKRUhKBqLDl3ir4w7 sQGbXwHEis1uB9HoiJAMrGkDUHLFNrv1s6NLWiqsotlhpuAnOctuqZtuI 2QsRuZR2YlZjQxsgZ7/ijCZD6TkkCVB62voULw+1uSngopd36A5+N4egH 9psI4vEGd59D9mjOaAnyKl8bfolrPgeJHYOB5Y3aJKZaVFSBhs08+Tx+Y WOadcJ8BxupMZHgGTD4l84ir+x0TQdfK64wyWtr4Chcmt33NYqpiy1dZN JybQo6ZfwUgBwikhlS2mCoXjZxh2X63xT7/ENpbCPNjBD61+8Yt4PttmB w==; X-IronPort-AV: E=McAfee;i="6500,9779,10510"; a="369772116" X-IronPort-AV: E=Sophos;i="5.95,212,1661842800"; d="scan'208";a="369772116" Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 25 Oct 2022 08:19:10 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6500,9779,10510"; a="736865621" X-IronPort-AV: E=Sophos;i="5.95,212,1661842800"; d="scan'208";a="736865621" Received: from chaop.bj.intel.com ([10.240.193.75]) by fmsmga002.fm.intel.com with ESMTP; 25 Oct 2022 08:18:59 -0700 From: Chao Peng To: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-arch@vger.kernel.org, linux-api@vger.kernel.org, linux-doc@vger.kernel.org, qemu-devel@nongnu.org Cc: Paolo Bonzini , Jonathan Corbet , Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , Thomas Gleixner , Ingo Molnar , Borislav Petkov , x86@kernel.org, "H . Peter Anvin" , Hugh Dickins , Jeff Layton , "J . Bruce Fields" , Andrew Morton , Shuah Khan , Mike Rapoport , Steven Price , "Maciej S . Szmigiero" , Vlastimil Babka , Vishal Annapurve , Yu Zhang , Chao Peng , "Kirill A . Shutemov" , luto@kernel.org, jun.nakajima@intel.com, dave.hansen@intel.com, ak@linux.intel.com, david@redhat.com, aarcange@redhat.com, ddutile@redhat.com, dhildenb@redhat.com, Quentin Perret , tabba@google.com, Michael Roth , mhocko@suse.com, Muchun Song , wei.w.wang@intel.com Subject: [PATCH v9 4/8] KVM: Use gfn instead of hva for mmu_notifier_retry Date: Tue, 25 Oct 2022 23:13:40 +0800 Message-Id: <20221025151344.3784230-5-chao.p.peng@linux.intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20221025151344.3784230-1-chao.p.peng@linux.intel.com> References: <20221025151344.3784230-1-chao.p.peng@linux.intel.com> MIME-Version: 1.0 ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1666711151; a=rsa-sha256; cv=none; b=bHFjXEeIwLpYrdERg2zyLJAnUk8Y5CacMAW2b131vtOQaxMrP+Rn1167p5Ns+wgVdmLZhr azCvKxr8vi74xZ0fU1AoABdnk+3+w5ogy2GCjq3MTU+5xQAUcCn60nAD1wk7HrHZS6SiFU xIFwjt3SP+26Kc4sbYzAXHHTeVmOGmQ= ARC-Authentication-Results: i=1; imf25.hostedemail.com; dkim=none ("invalid DKIM record") header.d=intel.com header.s=Intel header.b=YXqGQ3WX; dmarc=fail reason="No valid SPF" header.from=intel.com (policy=none); spf=none (imf25.hostedemail.com: domain of chao.p.peng@linux.intel.com has no SPF policy when checking 134.134.136.31) smtp.mailfrom=chao.p.peng@linux.intel.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1666711151; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=ZeCX6+XYJ88tSgL5hc/072IEYNeLVQ1q2js914cezdE=; b=zMbn0cOF3fPaTwGYDNqBXjbuV0UoXuIYLg/AGHncti9ZgOBXJQnM3AFj4p8fnerbg2Eghc +C/9ffgqbsNrMNCDjSXswAj/4JeUVksUn5F6EqVTshrbaDZZ8ZdZ17XdMpffppFBQu6WRY OyjzuwRfz09Gaognh1EP6F34L/7irso= X-Stat-Signature: 1iqmau88qmj5cgjoqfwiwdgtag55k1kr X-Rspam-User: X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: A11A2A0003 Authentication-Results: imf25.hostedemail.com; dkim=none ("invalid DKIM record") header.d=intel.com header.s=Intel header.b=YXqGQ3WX; dmarc=fail reason="No valid SPF" header.from=intel.com (policy=none); spf=none (imf25.hostedemail.com: domain of chao.p.peng@linux.intel.com has no SPF policy when checking 134.134.136.31) smtp.mailfrom=chao.p.peng@linux.intel.com X-HE-Tag: 1666711151-638316 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Currently in mmu_notifier validate path, hva range is recorded and then checked against in the mmu_notifier_retry_hva() of the page fault path. However, for the to be introduced private memory, a page fault may not have a hva associated, checking gfn(gpa) makes more sense. For existing non private memory case, gfn is expected to continue to work. The only downside is when aliasing multiple gfns to a single hva, the current algorithm of checking multiple ranges could result in a much larger range being rejected. Such aliasing should be uncommon, so the impact is expected small. It also fixes a bug in kvm_zap_gfn_range() which has already been using gfn when calling kvm_mmu_invalidate_begin/end() while these functions accept hva in current code. Signed-off-by: Chao Peng Reviewed-by: Fuad Tabba Signed-off-by: Sean Christopherson --- arch/x86/kvm/mmu/mmu.c | 2 +- include/linux/kvm_host.h | 18 +++++++--------- virt/kvm/kvm_main.c | 45 ++++++++++++++++++++++++++-------------- 3 files changed, 39 insertions(+), 26 deletions(-) diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c index 6f81539061d6..33b1aec44fb8 100644 --- a/arch/x86/kvm/mmu/mmu.c +++ b/arch/x86/kvm/mmu/mmu.c @@ -4217,7 +4217,7 @@ static bool is_page_fault_stale(struct kvm_vcpu *vcpu, return true; return fault->slot && - mmu_invalidate_retry_hva(vcpu->kvm, mmu_seq, fault->hva); + mmu_invalidate_retry_gfn(vcpu->kvm, mmu_seq, fault->gfn); } static int direct_page_fault(struct kvm_vcpu *vcpu, struct kvm_page_fault *fault) diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 739a7562a1f3..79e5cbc35fcf 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -775,8 +775,8 @@ struct kvm { struct mmu_notifier mmu_notifier; unsigned long mmu_invalidate_seq; long mmu_invalidate_in_progress; - unsigned long mmu_invalidate_range_start; - unsigned long mmu_invalidate_range_end; + gfn_t mmu_invalidate_range_start; + gfn_t mmu_invalidate_range_end; #endif struct list_head devices; u64 manual_dirty_log_protect; @@ -1365,10 +1365,8 @@ void kvm_mmu_free_memory_cache(struct kvm_mmu_memory_cache *mc); void *kvm_mmu_memory_cache_alloc(struct kvm_mmu_memory_cache *mc); #endif -void kvm_mmu_invalidate_begin(struct kvm *kvm, unsigned long start, - unsigned long end); -void kvm_mmu_invalidate_end(struct kvm *kvm, unsigned long start, - unsigned long end); +void kvm_mmu_invalidate_begin(struct kvm *kvm, gfn_t start, gfn_t end); +void kvm_mmu_invalidate_end(struct kvm *kvm, gfn_t start, gfn_t end); long kvm_arch_dev_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg); @@ -1937,9 +1935,9 @@ static inline int mmu_invalidate_retry(struct kvm *kvm, unsigned long mmu_seq) return 0; } -static inline int mmu_invalidate_retry_hva(struct kvm *kvm, +static inline int mmu_invalidate_retry_gfn(struct kvm *kvm, unsigned long mmu_seq, - unsigned long hva) + gfn_t gfn) { lockdep_assert_held(&kvm->mmu_lock); /* @@ -1949,8 +1947,8 @@ static inline int mmu_invalidate_retry_hva(struct kvm *kvm, * positives, due to shortcuts when handing concurrent invalidations. */ if (unlikely(kvm->mmu_invalidate_in_progress) && - hva >= kvm->mmu_invalidate_range_start && - hva < kvm->mmu_invalidate_range_end) + gfn >= kvm->mmu_invalidate_range_start && + gfn < kvm->mmu_invalidate_range_end) return 1; if (kvm->mmu_invalidate_seq != mmu_seq) return 1; diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 8dace78a0278..09c9cdeb773c 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -540,8 +540,7 @@ static void kvm_mmu_notifier_invalidate_range(struct mmu_notifier *mn, typedef bool (*hva_handler_t)(struct kvm *kvm, struct kvm_gfn_range *range); -typedef void (*on_lock_fn_t)(struct kvm *kvm, unsigned long start, - unsigned long end); +typedef void (*on_lock_fn_t)(struct kvm *kvm, gfn_t start, gfn_t end); typedef void (*on_unlock_fn_t)(struct kvm *kvm); @@ -628,7 +627,8 @@ static __always_inline int __kvm_handle_hva_range(struct kvm *kvm, locked = true; KVM_MMU_LOCK(kvm); if (!IS_KVM_NULL_FN(range->on_lock)) - range->on_lock(kvm, range->start, range->end); + range->on_lock(kvm, gfn_range.start, + gfn_range.end); if (IS_KVM_NULL_FN(range->handler)) break; } @@ -715,15 +715,9 @@ static void kvm_mmu_notifier_change_pte(struct mmu_notifier *mn, kvm_handle_hva_range(mn, address, address + 1, pte, kvm_set_spte_gfn); } -void kvm_mmu_invalidate_begin(struct kvm *kvm, unsigned long start, - unsigned long end) +static inline void update_invalidate_range(struct kvm *kvm, gfn_t start, + gfn_t end) { - /* - * The count increase must become visible at unlock time as no - * spte can be established without taking the mmu_lock and - * count is also read inside the mmu_lock critical section. - */ - kvm->mmu_invalidate_in_progress++; if (likely(kvm->mmu_invalidate_in_progress == 1)) { kvm->mmu_invalidate_range_start = start; kvm->mmu_invalidate_range_end = end; @@ -744,6 +738,28 @@ void kvm_mmu_invalidate_begin(struct kvm *kvm, unsigned long start, } } +static void mark_invalidate_in_progress(struct kvm *kvm, gfn_t start, gfn_t end) +{ + /* + * The count increase must become visible at unlock time as no + * spte can be established without taking the mmu_lock and + * count is also read inside the mmu_lock critical section. + */ + kvm->mmu_invalidate_in_progress++; +} + +static bool kvm_mmu_handle_gfn_range(struct kvm *kvm, struct kvm_gfn_range *range) +{ + update_invalidate_range(kvm, range->start, range->end); + return kvm_unmap_gfn_range(kvm, range); +} + +void kvm_mmu_invalidate_begin(struct kvm *kvm, gfn_t start, gfn_t end) +{ + mark_invalidate_in_progress(kvm, start, end); + update_invalidate_range(kvm, start, end); +} + static int kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn, const struct mmu_notifier_range *range) { @@ -752,8 +768,8 @@ static int kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn, .start = range->start, .end = range->end, .pte = __pte(0), - .handler = kvm_unmap_gfn_range, - .on_lock = kvm_mmu_invalidate_begin, + .handler = kvm_mmu_handle_gfn_range, + .on_lock = mark_invalidate_in_progress, .on_unlock = kvm_arch_guest_memory_reclaimed, .flush_on_ret = true, .may_block = mmu_notifier_range_blockable(range), @@ -791,8 +807,7 @@ static int kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn, return 0; } -void kvm_mmu_invalidate_end(struct kvm *kvm, unsigned long start, - unsigned long end) +void kvm_mmu_invalidate_end(struct kvm *kvm, gfn_t start, gfn_t end) { /* * This sequence increase will notify the kvm page fault that