From patchwork Tue Jan 18 13:21:14 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Chao Peng X-Patchwork-Id: 12716371 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 A536DC433FE for ; Tue, 18 Jan 2022 13:22:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S242923AbiARNWp (ORCPT ); Tue, 18 Jan 2022 08:22:45 -0500 Received: from mga12.intel.com ([192.55.52.136]:1542 "EHLO mga12.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243067AbiARNWf (ORCPT ); Tue, 18 Jan 2022 08:22:35 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1642512155; x=1674048155; h=from:to:cc:subject:date:message-id:in-reply-to: references; bh=7+c1sXkb+YZ1mlaZZMzVLTAk9/05+2xQQ6wigpDTqW0=; b=P7Fz1SZWXfY7pJCjSoYMJzwT7zc/N5iFarJDQnJMx4E52hnyV9OCJDh+ jXtW9643sl+ckOXcH4EObUEcRFnjLmhX8oiivYMycSBIFO72DUY3d5jWw sIFiIfyofPtGd3/xecpWwf70SN03VRmUFdCbqd/OFlA90wfmOwkVN+5cB xj1I7GkZez/Filt2NCMzJ2Zkl1Yo5O31O8c7mbXqLoZLLqwGM63gIhDub HOgVCTf2b7auiWM0JHA42LTW0OobQttrxFAzQP2ewvTagakWyEptyFZ1k v/AlUgLkunqk1RXbyBmr84NpEMriWrlaAgYHgopqTudTqobUwXpCMM4kk w==; X-IronPort-AV: E=McAfee;i="6200,9189,10230"; a="224791034" X-IronPort-AV: E=Sophos;i="5.88,297,1635231600"; d="scan'208";a="224791034" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 18 Jan 2022 05:22:34 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.88,297,1635231600"; d="scan'208";a="531791785" Received: from chaop.bj.intel.com ([10.240.192.101]) by orsmga008.jf.intel.com with ESMTP; 18 Jan 2022 05:22:27 -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, jun.nakajima@intel.com, dave.hansen@intel.com, ak@linux.intel.com, david@redhat.com Subject: [PATCH v4 05/12] KVM: Extend the memslot to support fd-based private memory Date: Tue, 18 Jan 2022 21:21:14 +0800 Message-Id: <20220118132121.31388-6-chao.p.peng@linux.intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20220118132121.31388-1-chao.p.peng@linux.intel.com> References: <20220118132121.31388-1-chao.p.peng@linux.intel.com> Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org Extend the memslot definition to provide fd-based private memory support by adding two new fields (private_fd/private_offset). The memslot then can maintain memory for both shared pages and private pages in a single memslot. Shared pages are provided by existing userspace_addr(hva) field and private pages are provided through the new private_fd/private_offset fields. Since there is no 'hva' concept anymore for private memory so we cannot rely on get_user_pages() to get a pfn, instead we use the newly added memfile_notifier to complete the same job. This new extension is indicated by a new flag KVM_MEM_PRIVATE. Signed-off-by: Yu Zhang Signed-off-by: Chao Peng --- include/linux/kvm_host.h | 7 +++++++ include/uapi/linux/kvm.h | 8 ++++++++ 2 files changed, 15 insertions(+) diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index f079820f52b5..5011ac35bc50 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -458,8 +458,15 @@ struct kvm_memory_slot { u32 flags; short id; u16 as_id; + struct file *private_file; + loff_t private_offset; }; +static inline bool kvm_slot_is_private(const struct kvm_memory_slot *slot) +{ + return slot && (slot->flags & KVM_MEM_PRIVATE); +} + static inline bool kvm_slot_dirty_track_enabled(const struct kvm_memory_slot *slot) { return slot->flags & KVM_MEM_LOG_DIRTY_PAGES; diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h index fbfd70d965c6..5d6dceb1b93e 100644 --- a/include/uapi/linux/kvm.h +++ b/include/uapi/linux/kvm.h @@ -103,6 +103,13 @@ struct kvm_userspace_memory_region { __u64 userspace_addr; /* start of the userspace allocated memory */ }; +struct kvm_userspace_memory_region_ext { + struct kvm_userspace_memory_region region; + __u64 private_offset; + __u32 private_fd; + __u32 padding[5]; +}; + /* * The bit 0 ~ bit 15 of kvm_memory_region::flags are visible for userspace, * other bits are reserved for kvm internal use which are defined in @@ -110,6 +117,7 @@ struct kvm_userspace_memory_region { */ #define KVM_MEM_LOG_DIRTY_PAGES (1UL << 0) #define KVM_MEM_READONLY (1UL << 1) +#define KVM_MEM_PRIVATE (1UL << 2) /* for KVM_IRQ_LINE */ struct kvm_irq_level {