[PATCH v10 07/15] KVM: x86: define kvm_arch_gmem_supports_no_direct_map()

From: "Kalyazin, Nikita" <kalyazin@amazon.co.uk>
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Subject: [PATCH v10 07/15] KVM: x86: define kvm_arch_gmem_supports_no_direct_map()
Date: Mon, 26 Jan 2026 16:50:08 +0000	[thread overview]
Message-ID: <20260126164445.11867-8-kalyazin@amazon.com> (raw)
In-Reply-To: <20260126164445.11867-1-kalyazin@amazon.com>

From: Patrick Roy <patrick.roy@linux.dev>

x86 supports GUEST_MEMFD_FLAG_NO_DIRECT_MAP whenever direct map
modifications are possible (which is always the case).

Signed-off-by: Patrick Roy <patrick.roy@linux.dev>
Reviewed-by: Ackerley Tng <ackerleytng@google.com>
Signed-off-by: Nikita Kalyazin <kalyazin@amazon.com>
---
 arch/x86/include/asm/kvm_host.h | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 5a3bfa293e8b..68bd29a52f24 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -28,6 +28,7 @@
 #include <linux/sched/vhost_task.h>
 #include <linux/call_once.h>
 #include <linux/atomic.h>
+#include <linux/set_memory.h>
 
 #include <asm/apic.h>
 #include <asm/pvclock-abi.h>
@@ -2481,4 +2482,12 @@ static inline bool kvm_arch_has_irq_bypass(void)
 	return enable_device_posted_irqs;
 }
 
+#ifdef CONFIG_KVM_GUEST_MEMFD
+static inline bool kvm_arch_gmem_supports_no_direct_map(void)
+{
+	return can_set_direct_map();
+}
+#define kvm_arch_gmem_supports_no_direct_map kvm_arch_gmem_supports_no_direct_map
+#endif /* CONFIG_KVM_GUEST_MEMFD */
+
 #endif /* _ASM_X86_KVM_HOST_H */
-- 
2.50.1

