From patchwork Tue Dec 21 15:11:17 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chao Peng X-Patchwork-Id: 12689911 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id F397AC4332F for ; Tue, 21 Dec 2021 15:13:07 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239115AbhLUPNG (ORCPT ); Tue, 21 Dec 2021 10:13:06 -0500 Received: from mga18.intel.com ([134.134.136.126]:45664 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239092AbhLUPND (ORCPT ); Tue, 21 Dec 2021 10:13:03 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1640099583; x=1671635583; h=from:to:cc:subject:date:message-id:in-reply-to: references; bh=COdj1UvXQdkAqzxtXCPYFm0EISfGJg8Z8mzxkFecT00=; b=beU8rVoQBTWa+Tw16yFjPtrbBml6hlZe6XcOPyOAa01v1mG6kFtUBklJ eKkGvn/ip+GCdbXlV5KTvaSgBDIqpaBnZzqKI1lyXYfuHaDy+vIqwpPzL YyARbCY7gxLlv/8j+NN9Be2l0q4Efjzn1PL44FF/9KV0gMN76EfTFfcQ0 qmzzF6l5D5hCYkIHwrhvkxtQwjqN/9/JYT4q6H3NMui80zLeksHnzu0m+ mJ/z5Cq3M3kFU+wehalIE0PZCetcwUCD2+LWcEnibHYM5BA13DJa89l1M UQa9tt4nA2j1I6sPEjYLVzy0dqjsBoLUg0P850tx3FxeBFSBhZq5j41hm g==; X-IronPort-AV: E=McAfee;i="6200,9189,10204"; a="227259435" X-IronPort-AV: E=Sophos;i="5.88,223,1635231600"; d="scan'208";a="227259435" Received: from orsmga005.jf.intel.com ([10.7.209.41]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 Dec 2021 07:13:03 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.88,223,1635231600"; d="scan'208";a="684688485" Received: from chaop.bj.intel.com ([10.240.192.101]) by orsmga005.jf.intel.com with ESMTP; 21 Dec 2021 07:12:55 -0800 From: Chao Peng To: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-fsdevel@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 , Yu Zhang , Chao Peng , "Kirill A . Shutemov" , luto@kernel.org, john.ji@intel.com, susie.li@intel.com, jun.nakajima@intel.com, dave.hansen@intel.com, ak@linux.intel.com, david@redhat.com Subject: [PATCH v3 07/15] KVM: Special handling for fd-based memory invalidation Date: Tue, 21 Dec 2021 23:11:17 +0800 Message-Id: <20211221151125.19446-8-chao.p.peng@linux.intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20211221151125.19446-1-chao.p.peng@linux.intel.com> References: <20211221151125.19446-1-chao.p.peng@linux.intel.com> Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org For fd-based guest memory, the memory backend (e.g. the fd provider) should notify KVM to unmap/invalidate the privated memory from KVM second MMU when userspace punches hole on the fd (e.g. when userspace converts private memory to shared memory). To support fd-based memory invalidation, existing hva-based memory invalidation needs to be extended. A new 'inode' for the fd is passed in from memfd_falloc_notifier and the 'start/end' will represent start/end offset in the fd instead of hva range. During the invalidation KVM needs to check this inode against that in the memslot. Only when the 'inode' in memslot equals to the passed-in 'inode' we should invalidate the mapping in KVM. Signed-off-by: Yu Zhang Signed-off-by: Chao Peng --- virt/kvm/kvm_main.c | 23 +++++++++++++++++++---- 1 file changed, 19 insertions(+), 4 deletions(-) diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 856f89ed8ab5..0f2d1002f6a7 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -479,6 +479,7 @@ typedef void (*on_lock_fn_t)(struct kvm *kvm, unsigned long start, struct kvm_useraddr_range { unsigned long start; unsigned long end; + struct inode *inode; pte_t pte; gfn_handler_t handler; on_lock_fn_t on_lock; @@ -519,9 +520,19 @@ static __always_inline int __kvm_handle_useraddr_range(struct kvm *kvm, slots = __kvm_memslots(kvm, i); kvm_for_each_memslot(slot, slots) { unsigned long useraddr_start, useraddr_end; + unsigned long useraddr_base; - useraddr_start = max(range->start, slot->userspace_addr); - useraddr_end = min(range->end, slot->userspace_addr + + if (range->inode) { + if (!slot->file || + slot->file->f_inode != range->inode) + continue; + useraddr_base = slot->file_ofs; + } else + useraddr_base = slot->userspace_addr; + + + useraddr_start = max(range->start, useraddr_base); + useraddr_end = min(range->end, useraddr_base + (slot->npages << PAGE_SHIFT)); if (useraddr_start >= useraddr_end) continue; @@ -540,10 +551,10 @@ static __always_inline int __kvm_handle_useraddr_range(struct kvm *kvm, * {gfn_start, gfn_start+1, ..., gfn_end-1}. */ gfn_range.start = useraddr_to_gfn_memslot(useraddr_start, - slot, true); + slot, !range->inode); gfn_range.end = useraddr_to_gfn_memslot( useraddr_end + PAGE_SIZE - 1, - slot, true); + slot, !range->inode); gfn_range.slot = slot; if (!locked) { @@ -585,6 +596,7 @@ static __always_inline int kvm_handle_hva_range(struct mmu_notifier *mn, .on_lock = (void *)kvm_null_fn, .flush_on_ret = true, .may_block = false, + .inode = NULL, }; return __kvm_handle_useraddr_range(kvm, &range); @@ -604,6 +616,7 @@ static __always_inline int kvm_handle_hva_range_no_flush(struct mmu_notifier *mn .on_lock = (void *)kvm_null_fn, .flush_on_ret = false, .may_block = false, + .inode = NULL, }; return __kvm_handle_useraddr_range(kvm, &range); @@ -672,6 +685,7 @@ static int kvm_mmu_notifier_invalidate_range_start(struct mmu_notifier *mn, .on_lock = kvm_inc_notifier_count, .flush_on_ret = true, .may_block = mmu_notifier_range_blockable(range), + .inode = NULL, }; trace_kvm_unmap_hva_range(range->start, range->end); @@ -723,6 +737,7 @@ static void kvm_mmu_notifier_invalidate_range_end(struct mmu_notifier *mn, .on_lock = kvm_dec_notifier_count, .flush_on_ret = false, .may_block = mmu_notifier_range_blockable(range), + .inode = NULL, }; bool wake;