From nobody Mon Feb 9 13:00:12 2026 Received: from mail-pg1-f201.google.com (mail-pg1-f201.google.com [209.85.215.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 559303431F2 for ; Thu, 16 Oct 2025 17:30:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.215.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760635831; cv=none; b=c0vzA+s+vavLmSSUYfDrTqH+jPathNk8/dlONE0VhgMEEx0pgmG8bgVqmLC1OIwvMJlPizYNwOMC5FhyIHzqOU+b8/LMMoudmdVy2e2kxicTBqXnPPJKToUiuXeNH5UT7Zoo/MEXGTlnMBZnAavH5kqoJWpmThVIKBL7Hrc//u8= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760635831; c=relaxed/simple; bh=u73IkWxovHfIqFa1WeugdviVlKOG53gOaetPwlyyztU=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=NRTiprH/FG2xjxlfhcmvQ3gqnFUM+8W0xhu2zfxzy8Z9zN3tFo64E6AceYuL0Bt2auzWGkTkcjXDUzRokrrHg/8K6hPBm5+sOUEkwoxUr6Htee80ZgpsYpXntq6BG6v4JDQko48ONgpgsRuLox8MHRhNQFyWKgWWBrznBs/uphU= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=l41+waih; arc=none smtp.client-ip=209.85.215.201 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="l41+waih" Received: by mail-pg1-f201.google.com with SMTP id 41be03b00d2f7-b6097ca315bso1569184a12.3 for ; Thu, 16 Oct 2025 10:30:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1760635829; x=1761240629; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:from:to:cc:subject:date:message-id:reply-to; bh=hVBqs1fBWLjUqhKekNBXs2j0fRJmcNGrbmsvLjXeKrQ=; b=l41+waihuLTGtQNanwUNjhCuRxkZ3+g4RHJUpXsuNF66JXDSDFLirRAffRqPLKh+8n undGXyArwk7vBbUulc9lUPCFIjqedupCtRNwtY4kFF+AScEWT4wYWc56Dh8CiA23P5Wl rK+yNE/zrFx4lpAbLZaRjAbostWFNoaTTyphDGopvTe0G+a0ppjKOC6FE6XID50SJkOk nS7+GicXjfA9TraLlg0zgh+plotiBHZqcL3wGallJCFfBshgqBNyLXY1y7Ne4gd47pz8 cwX5TWZe9oScoxZcVXOPPqtdOuTrMp09yaHcJKC/aJVuQlFMQ9na7izAYaTJTveg8yTQ xAGA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1760635829; x=1761240629; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:reply-to:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=hVBqs1fBWLjUqhKekNBXs2j0fRJmcNGrbmsvLjXeKrQ=; b=OZ9Etam5aWDB0v2I8h8WJsswUdQIIRaCmlV+cGPtZdLcERy4MRA3MkDaO1783Kkmnz MfskMh7ymBq/X8zovtmglioMRI2yADad6cWEVb9wSvieqEc9N9HFJGtdJj/Gim463O3n 9bZE7va5oEpl2lxXCm1xHnxenwRvPjtBjCZDCbm9KFj4cinAiqG4y7jy6EKjZYO4mWsv OgX+ZAq1GVU63HUKRVVhkweeGcqMBag0vm/1A5UQvIhk/bHfS09epv4q5+w9ByS2HE4U KGnL7O3rstYA4z4YBAJPOJwjZt0w/h+oOFyEVpiGw7l3Y4q2mR8VlYolhdTki8DQu3QC 5AXA== X-Forwarded-Encrypted: i=1; AJvYcCVpDvGsYfZrrRYEGdvxYl/cttdUfMNOCkwqpJFVzGet7pYZ7SU6DSWz3DO6qzjtnIyISzud0VKEZh668pw=@vger.kernel.org X-Gm-Message-State: AOJu0YwX3uwtHehSUXJdBNjQhuXh7W6o3L3bOcFL/yCvu4LSsAf0IUNQ bI23n6YB0JmsQ5boKKL6okiN28nvegpKtey/eq1cNYsQG6TUDIqyCcFlxNYj7hZbZEbMJWzq2Zh GIAD0tg== X-Google-Smtp-Source: AGHT+IGe2t05unDim4uDryBf0T+QferPUXjPaV2LK4Nd4NgexnAWeTiux+wqiz6ZgBu9e+7IBbrnySiYCWM= X-Received: from pja6.prod.google.com ([2002:a17:90b:5486:b0:33b:51fe:1a79]) (user=seanjc job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6a20:2590:b0:2e0:9b1a:640a with SMTP id adf61e73a8af0-334a8485506mr977560637.3.1760635829602; Thu, 16 Oct 2025 10:30:29 -0700 (PDT) Reply-To: Sean Christopherson Date: Thu, 16 Oct 2025 10:28:53 -0700 In-Reply-To: <20251016172853.52451-1-seanjc@google.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20251016172853.52451-1-seanjc@google.com> X-Mailer: git-send-email 2.51.0.858.gf9c4a03a3a-goog Message-ID: <20251016172853.52451-13-seanjc@google.com> Subject: [PATCH v13 12/12] KVM: guest_memfd: Add gmem_inode.flags field instead of using i_private From: Sean Christopherson To: Miguel Ojeda , Marc Zyngier , Oliver Upton , Paolo Bonzini , Sean Christopherson Cc: linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Ackerley Tng , Shivank Garg , David Hildenbrand , Fuad Tabba , Ashish Kalra , Vlastimil Babka Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Track a guest_memfd instance's flags in gmem_inode instead of burying them in i_private. Burning an extra 8 bytes per inode is well worth the added clarity provided by explicit tracking. Signed-off-by: Sean Christopherson Reviewed-by: Shivank Garg Tested-by: Shivank Garg --- virt/kvm/guest_memfd.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/virt/kvm/guest_memfd.c b/virt/kvm/guest_memfd.c index 4463643bd0a2..20f6e7fab58d 100644 --- a/virt/kvm/guest_memfd.c +++ b/virt/kvm/guest_memfd.c @@ -30,6 +30,8 @@ struct gmem_file { struct gmem_inode { struct shared_policy policy; struct inode vfs_inode; + + u64 flags; }; =20 static __always_inline struct gmem_inode *GMEM_I(struct inode *inode) @@ -154,7 +156,7 @@ static struct folio *kvm_gmem_get_folio(struct inode *i= node, pgoff_t index) =20 static enum kvm_gfn_range_filter kvm_gmem_get_invalidate_filter(struct ino= de *inode) { - if ((u64)inode->i_private & GUEST_MEMFD_FLAG_INIT_SHARED) + if (GMEM_I(inode)->flags & GUEST_MEMFD_FLAG_INIT_SHARED) return KVM_FILTER_SHARED; =20 return KVM_FILTER_PRIVATE; @@ -385,9 +387,7 @@ static inline struct file *kvm_gmem_get_file(struct kvm= _memory_slot *slot) =20 static bool kvm_gmem_supports_mmap(struct inode *inode) { - const u64 flags =3D (u64)inode->i_private; - - return flags & GUEST_MEMFD_FLAG_MMAP; + return GMEM_I(inode)->flags & GUEST_MEMFD_FLAG_MMAP; } =20 static vm_fault_t kvm_gmem_fault_user_mapping(struct vm_fault *vmf) @@ -399,7 +399,7 @@ static vm_fault_t kvm_gmem_fault_user_mapping(struct vm= _fault *vmf) if (((loff_t)vmf->pgoff << PAGE_SHIFT) >=3D i_size_read(inode)) return VM_FAULT_SIGBUS; =20 - if (!((u64)inode->i_private & GUEST_MEMFD_FLAG_INIT_SHARED)) + if (!(GMEM_I(inode)->flags & GUEST_MEMFD_FLAG_INIT_SHARED)) return VM_FAULT_SIGBUS; =20 folio =3D kvm_gmem_get_folio(inode, vmf->pgoff); @@ -588,7 +588,6 @@ static int __kvm_gmem_create(struct kvm *kvm, loff_t si= ze, u64 flags) goto err_fops; } =20 - inode->i_private =3D (void *)(unsigned long)flags; inode->i_op =3D &kvm_gmem_iops; inode->i_mapping->a_ops =3D &kvm_gmem_aops; inode->i_mode |=3D S_IFREG; @@ -598,6 +597,8 @@ static int __kvm_gmem_create(struct kvm *kvm, loff_t si= ze, u64 flags) /* Unmovable mappings are supposed to be marked unevictable as well. */ WARN_ON_ONCE(!mapping_unevictable(inode->i_mapping)); =20 + GMEM_I(inode)->flags =3D flags; + file =3D alloc_file_pseudo(inode, kvm_gmem_mnt, name, O_RDWR, &kvm_gmem_f= ops); if (IS_ERR(file)) { err =3D PTR_ERR(file); @@ -917,6 +918,8 @@ static struct inode *kvm_gmem_alloc_inode(struct super_= block *sb) return NULL; =20 mpol_shared_policy_init(&gi->policy, NULL); + + gi->flags =3D 0; return &gi->vfs_inode; } =20 --=20 2.51.0.858.gf9c4a03a3a-goog