Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   Emanuele Giuseppe Esposito <eesposit@redhat.com>
To:     kvm@vger.kernel.org
Cc:     Paolo Bonzini <pbonzini@redhat.com>,
        Sean Christopherson <seanjc@google.com>,
        Vitaly Kuznetsov <vkuznets@redhat.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Jim Mattson <jmattson@google.com>,
        Joerg Roedel <joro@8bytes.org>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        David Hildenbrand <david@redhat.com>,
        Maxim Levitsky <mlevitsk@redhat.com>, x86@kernel.org,
        "H. Peter Anvin" <hpa@zytor.com>, linux-kernel@vger.kernel.org,
        Emanuele Giuseppe Esposito <eesposit@redhat.com>
Subject: [RFC PATCH 2/9] kvm.h: introduce KVM_SET_USER_MEMORY_REGION_LIST ioctl
Date:   Fri,  9 Sep 2022 06:44:59 -0400
Message-Id: <20220909104506.738478-3-eesposit@redhat.com>
In-Reply-To: <20220909104506.738478-1-eesposit@redhat.com>
References: <20220909104506.738478-1-eesposit@redhat.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

This IOCTL enables atomic update of multiple memslots.
The userspace application provides a kvm_userspace_memory_region_list
containing a list of entries, each representing a modification to be
performed to a memslot.

Requests with invalidate_slot == 1 are pre-processed, because they
are ther DELETE or MOVE, and therefore the memslot must be first
replaced with a copy marked as KVM_MEMSLOT_INVALID, and then replaced.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
---
 include/uapi/linux/kvm.h | 21 ++++++++++++++++++++-
 1 file changed, 20 insertions(+), 1 deletion(-)

diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index a36e78710382..673496b91a25 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -103,6 +103,24 @@ struct kvm_userspace_memory_region {
 	__u64 userspace_addr; /* start of the userspace allocated memory */
 };
 
+/* for KVM_SET_USER_MEMORY_REGION_LIST */
+struct kvm_userspace_memory_region_entry {
+	__u32 slot;
+	__u32 flags;
+	__u64 guest_phys_addr;
+	__u64 memory_size; /* bytes */
+	__u64 userspace_addr; /* start of the userspace allocated memory */
+	__u8 invalidate_slot;
+	__u8 padding[31];
+};
+
+/* for KVM_SET_USER_MEMORY_REGION_LIST */
+struct kvm_userspace_memory_region_list {
+	__u32 nent;
+	__u32 flags;
+	struct kvm_userspace_memory_region_entry entries[0];
+};
+
 /*
  * 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
@@ -1444,7 +1462,8 @@ struct kvm_vfio_spapr_tce {
 					struct kvm_userspace_memory_region)
 #define KVM_SET_TSS_ADDR          _IO(KVMIO,   0x47)
 #define KVM_SET_IDENTITY_MAP_ADDR _IOW(KVMIO,  0x48, __u64)
-
+#define KVM_SET_USER_MEMORY_REGION_LIST _IOW(KVMIO, 0x49, \
+					struct kvm_userspace_memory_region_list)
 /* enable ucontrol for s390 */
 struct kvm_s390_ucas_mapping {
 	__u64 user_addr;
-- 
2.31.1