From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E95D722126C; Fri, 19 Jun 2026 00:31:47 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781829108; cv=none; b=m6BU1boVm6bRoExXxcDhkRa8TcO/QdM1PFueYOm+52s5TXQ3JRUOrEL9sctgHBu07H2dinhLU0BJxjAL6ZQXwfiDlCLBSgFAXdk1KJXe9KbmVx1qzJdg512RoXS7A3en2X11cGLOqlZ5QSk+CLIROxMsWHVIp1JAFy4HTlId0aw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1781829108; c=relaxed/simple; bh=0H2IgUs4dzVuCzjrH58X/cGXGyAD1oZYLqxV+FhozK0=; h=From:Date:Subject:MIME-Version:Content-Type:Message-Id:References: In-Reply-To:To:Cc; b=BWrrhGiGxD+VoFt8S7Ftkx/4jNWkmZnINVthpk1ai7V5Pl1FYhJ+r+cBL55jySPFJhvDEK01s557CbYCeFAV14+HYb2FI54z0RtJKoYQRe2hJSZRvelcLuKf8qWhKSsfZ5M2PpQ0ZPVvAdhGUnbhFU5aa5rDxWsi325ObOlwWeo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=UQ8+Sr/4; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="UQ8+Sr/4" Received: by smtp.kernel.org (Postfix) with ESMTPS id 757D4C4DE13; Fri, 19 Jun 2026 00:31:47 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1781829107; bh=0H2IgUs4dzVuCzjrH58X/cGXGyAD1oZYLqxV+FhozK0=; h=From:Date:Subject:References:In-Reply-To:To:Cc:Reply-To:From; b=UQ8+Sr/4zjoDRjzngdzG+gtJ/Lw3UMYE+bD4PvXcNhxrUWdom4NYXl1FsewAJlomQ jO5O50TozuER7C5k837zaleXt6t/z2YLcKFtI8d8wARE++jPZDpvMKxirvdhKD+x+1 jWxoBAZ/97yo3sV0B6DnucD4LnwyQu1nxPgO2QSm6hRc+4CLl2DJspZHyvhUMOoed7 ABe1WaS2sWYfpjiSUr5b+Y9Eo0J1ECJngHQBTyVys3pJiGeTSrrZ98qVCx2xxzwopN U6UVESkCiBrwi+a0cHBWlV6CfDDJvI9qM61ALWnHGUpNyqnmHaQiqmtPHogkTlPVJg gWqW/fF/plK2w== Received: from aws-us-west-2-korg-lkml-1.web.codeaurora.org (localhost.localdomain [127.0.0.1]) by smtp.lore.kernel.org (Postfix) with ESMTP id 68400CD98FA; Fri, 19 Jun 2026 00:31:47 +0000 (UTC) From: Ackerley Tng via B4 Relay Date: Thu, 18 Jun 2026 17:31:45 -0700 Subject: [PATCH v8 08/46] KVM: Provide generic interface for checking memory private/shared status Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Message-Id: <20260618-gmem-inplace-conversion-v8-8-9d2959357853@google.com> References: <20260618-gmem-inplace-conversion-v8-0-9d2959357853@google.com> In-Reply-To: <20260618-gmem-inplace-conversion-v8-0-9d2959357853@google.com> To: aik@amd.com, andrew.jones@linux.dev, binbin.wu@linux.intel.com, brauner@kernel.org, chao.p.peng@linux.intel.com, david@kernel.org, jmattson@google.com, jthoughton@google.com, michael.roth@amd.com, oupton@kernel.org, pankaj.gupta@amd.com, qperret@google.com, rick.p.edgecombe@intel.com, rientjes@google.com, shivankg@amd.com, steven.price@arm.com, tabba@google.com, willy@infradead.org, wyihan@google.com, yan.y.zhao@intel.com, forkloop@google.com, pratyush@kernel.org, suzuki.poulose@arm.com, aneesh.kumar@kernel.org, liam@infradead.org, Paolo Bonzini , Sean Christopherson , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , x86@kernel.org, "H. Peter Anvin" , Steven Rostedt , Masami Hiramatsu , Mathieu Desnoyers , Jonathan Corbet , Shuah Khan , Shuah Khan , Vishal Annapurve , Andrew Morton , Chris Li , Kairui Song , Kemeng Shi , Nhat Pham , Barry Song , Axel Rasmussen , Yuanchu Xie , Wei Xu , Youngjun Park , Qi Zheng , Shakeel Butt , Kiryl Shutsemau , Baoquan He , Jason Gunthorpe , Vlastimil Babka , Baoquan He Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, linux-trace-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-mm@kvack.org, linux-coco@lists.linux.dev, Ackerley Tng X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=ed25519-sha256; t=1781829104; l=2977; i=ackerleytng@google.com; s=20260225; h=from:subject:message-id; bh=r3yEEx41b7aixiqjjkGloSiqCgEFBbHdxuv0LadMDeU=; b=xTEebEXKr9XNrY/4ClqfxpuFQfAULsVn5D/QsFNVlsoF8ytkLlqq/u9gEsk/jwR8B7+W/Cpf+ L3vkBV+fRWvDMKig52v8OLurUuaCFzAdR6qPRXMtWgqncjfEOV0c6zv X-Developer-Key: i=ackerleytng@google.com; a=ed25519; pk=sAZDYXdm6Iz8FHitpHeFlCMXwabodTm7p8/3/8xUxuU= X-Endpoint-Received: by B4 Relay for ackerleytng@google.com/20260225 with auth_id=649 X-Original-From: Ackerley Tng Reply-To: ackerleytng@google.com From: Sean Christopherson Introduce a generic kvm_mem_is_private() interface using a static call to determine if a GFN is private. This allows the implementation for checking a GFN's private/shared status to be set at runtime. In preparation for choosing implementations between a guest_memfd lookup and the existing VM attribute lookup, rename the existing VM-attribute-based check to kvm_vm_mem_is_private to emphasize that it looks up VM attributes. Signed-off-by: Sean Christopherson --- include/linux/kvm_host.h | 12 +++++++++++- virt/kvm/kvm_main.c | 15 +++++++++++++++ 2 files changed, 26 insertions(+), 1 deletion(-) diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index eb26d4ea8945a..3915da2a61778 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -2546,7 +2546,7 @@ bool kvm_arch_pre_set_memory_attributes(struct kvm *kvm, bool kvm_arch_post_set_memory_attributes(struct kvm *kvm, struct kvm_gfn_range *range); -static inline bool kvm_mem_is_private(struct kvm *kvm, gfn_t gfn) +static inline bool kvm_vm_mem_is_private(struct kvm *kvm, gfn_t gfn) { return kvm_get_vm_memory_attributes(kvm, gfn) & KVM_MEMORY_ATTRIBUTE_PRIVATE; } @@ -2557,6 +2557,16 @@ static inline bool kvm_mem_range_is_private(struct kvm *kvm, gfn_t start, KVM_MEMORY_ATTRIBUTE_PRIVATE, KVM_MEMORY_ATTRIBUTE_PRIVATE); } +#endif /* CONFIG_KVM_VM_MEMORY_ATTRIBUTES */ + +#ifdef kvm_arch_has_private_mem +typedef bool (kvm_mem_is_private_t)(struct kvm *kvm, gfn_t gfn); +DECLARE_STATIC_CALL(__kvm_mem_is_private, kvm_mem_is_private_t); + +static inline bool kvm_mem_is_private(struct kvm *kvm, gfn_t gfn) +{ + return static_call(__kvm_mem_is_private)(kvm, gfn); +} #else static inline bool kvm_mem_is_private(struct kvm *kvm, gfn_t gfn) { diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 6669f1477013c..8b238e461b854 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -2627,6 +2627,20 @@ static int kvm_vm_ioctl_set_mem_attributes(struct kvm *kvm, } #endif /* CONFIG_KVM_VM_MEMORY_ATTRIBUTES */ +#ifdef kvm_arch_has_private_mem +DEFINE_STATIC_CALL_RET0(__kvm_mem_is_private, kvm_mem_is_private_t); +EXPORT_STATIC_CALL_GPL(__kvm_mem_is_private); + +static void kvm_init_memory_attributes(void) +{ +#ifdef CONFIG_KVM_VM_MEMORY_ATTRIBUTES + static_call_update(__kvm_mem_is_private, kvm_vm_mem_is_private); +#endif +} +#else +static void kvm_init_memory_attributes(void) { } +#endif + struct kvm_memory_slot *gfn_to_memslot(struct kvm *kvm, gfn_t gfn) { return __gfn_to_memslot(kvm_memslots(kvm), gfn); @@ -6528,6 +6542,7 @@ int kvm_init(unsigned vcpu_size, unsigned vcpu_align, struct module *module) kvm_preempt_ops.sched_in = kvm_sched_in; kvm_preempt_ops.sched_out = kvm_sched_out; + kvm_init_memory_attributes(); kvm_init_debug(); r = kvm_vfio_ops_init(); -- 2.55.0.rc0.738.g0c8ab3ebcc-goog