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AJvYcCXssNOC3KXlhBSSZs8CMorLafZ0/dKvHGUwOq0kTlFDk15iT6YKA70m7pR2KgqmHknx9HgBtJ9WiVwzJA1tNNF4@lists.infradead.org X-Gm-Message-State: AOJu0YyhzisJxQ87F7NixOEkQRddLissEB6UX77D7zu53wlljGxJR+sa 94sHEizL95nZvX77aoCN44kXJvbhCXM99Kb1GouPb/QC7+wQB0wm2ZyAIc16hkiLmShwBIgWd6t f5A== X-Google-Smtp-Source: AGHT+IGz6mODxZTH5agCMYiGZey+8PwFJu50se4JqpXBNG0SwyKrN9TWGGQJqqmZYCdc2Fnc7eka1IGyLLE= X-Received: from zagreus.c.googlers.com ([fda3:e722:ac3:cc00:9d:3983:ac13:c240]) (user=seanjc job=sendgmr) by 2002:a81:ad16:0:b0:6c1:298e:5a7 with SMTP id 00721157ae682-6e3224662ffmr1632867b3.5.1728584694780; Thu, 10 Oct 2024 11:24:54 -0700 (PDT) Date: Thu, 10 Oct 2024 11:23:05 -0700 In-Reply-To: <20241010182427.1434605-1-seanjc@google.com> Mime-Version: 1.0 References: <20241010182427.1434605-1-seanjc@google.com> X-Mailer: git-send-email 2.47.0.rc1.288.g06298d1525-goog Message-ID: <20241010182427.1434605-4-seanjc@google.com> Subject: [PATCH v13 03/85] KVM: Add kvm_release_page_unused() API to put pages that KVM never consumes From: Sean Christopherson To: Paolo Bonzini , Marc Zyngier , Oliver Upton , Tianrui Zhao , Bibo Mao , Huacai Chen , Michael Ellerman , Anup Patel , Paul Walmsley , Palmer Dabbelt , Albert Ou , Christian Borntraeger , Janosch Frank , Claudio Imbrenda , Sean Christopherson Cc: kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, loongarch@lists.linux.dev, linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, " =?utf-8?q?Alex_Benn=C3=A9e?= " , Yan Zhao , David Matlack , David Stevens , Andrew Jones X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20241010_112456_201885_577E4E6F X-CRM114-Status: GOOD ( 10.02 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Sean Christopherson Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Add an API to release an unused page, i.e. to put a page without marking it accessed or dirty. The API will be used when KVM faults-in a page but bails before installing the guest mapping (and other similar flows). Reviewed-by: Alex Bennée Tested-by: Alex Bennée Signed-off-by: Sean Christopherson --- include/linux/kvm_host.h | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index ee186a1fbaad..ab4485b2bddc 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -1216,6 +1216,15 @@ unsigned long gfn_to_hva_prot(struct kvm *kvm, gfn_t gfn, bool *writable); unsigned long gfn_to_hva_memslot(struct kvm_memory_slot *slot, gfn_t gfn); unsigned long gfn_to_hva_memslot_prot(struct kvm_memory_slot *slot, gfn_t gfn, bool *writable); + +static inline void kvm_release_page_unused(struct page *page) +{ + if (!page) + return; + + put_page(page); +} + void kvm_release_page_clean(struct page *page); void kvm_release_page_dirty(struct page *page);