From: Brijesh Singh <brijesh.singh@amd.com>
To: linux-kernel@vger.kernel.org, x86@kernel.org, kvm@vger.kernel.org
Cc: Thomas Gleixner <tglx@linutronix.de>, Borislav Petkov <bp@suse.de>,
        Joerg Roedel <joro@8bytes.org>, "Michael S . Tsirkin" <mst@redhat.com>,
        Paolo Bonzini <pbonzini@redhat.com>,
        =?UTF-8?q?=5C=22Radim=20Kr=C4=8Dm=C3=A1=C5=99=5C=22?= 
        <rkrcmar@redhat.com>,
        Tom Lendacky <thomas.lendacky@amd.com>,
        Brijesh Singh <brijesh.singh@amd.com>
Subject: [RFC Part2 PATCH v3 04/26] KVM: SVM: Prepare to reserve asid for SEV guest
Date: Mon, 24 Jul 2017 15:02:41 -0500
Message-Id: <20170724200303.12197-5-brijesh.singh@amd.com>
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In current implementation, asid allocation starts from 1, this patch
adds a min_asid variable in svm_vcpu structure to allow starting asid
from something other than 1.

Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
---
 arch/x86/kvm/svm.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 6af04dd..46f41bb 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -511,6 +511,7 @@ struct svm_cpu_data {
 	u64 asid_generation;
 	u32 max_asid;
 	u32 next_asid;
+	u32 min_asid;
 	struct kvm_ldttss_desc *tss_desc;
 
 	struct page *save_area;
@@ -768,6 +769,7 @@ static int svm_hardware_enable(void)
 	sd->asid_generation = 1;
 	sd->max_asid = cpuid_ebx(SVM_CPUID_FUNC) - 1;
 	sd->next_asid = sd->max_asid + 1;
+	sd->min_asid = 1;
 
 	gdt = get_current_gdt_rw();
 	sd->tss_desc = (struct kvm_ldttss_desc *)(gdt + GDT_ENTRY_TSS);
@@ -2072,7 +2074,7 @@ static void new_asid(struct vcpu_svm *svm, struct svm_cpu_data *sd)
 {
 	if (sd->next_asid > sd->max_asid) {
 		++sd->asid_generation;
-		sd->next_asid = 1;
+		sd->next_asid = sd->min_asid;
 		svm->vmcb->control.tlb_ctl = TLB_CONTROL_FLUSH_ALL_ASID;
 	}
 
-- 
2.9.4