i386: Hyper-V Support extended GVA ranges for TLB flush hypercalls

KVM kind of supported "extended GVA ranges" (up to 4095 additional GFNs
per hypercall) since the implementation of Hyper-V PV TLB flush feature
(Linux-4.18) as regardless of the request, full TLB flush was always
performed. "Extended GVA ranges for TLB flush hypercalls" feature bit
wasn't exposed then. Now, as KVM gains support for fine-grained TLB
flush handling, exposing this feature starts making sense.

Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Message-Id: <20220525115949.1294004-5-vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/docs/hyperv.txt b/docs/hyperv.txt
index af1b10c0b3d183a36bd747bea0a3d5a2178ff4e8..4b132b1c941a39cf5af00352c263c0eb942e0443 100644 (file)
--- a/docs/hyperv.txt
+++ b/docs/hyperv.txt
@@ -255,6 +255,13 @@ Hyper-V specification allows to pass parameters for certain hypercalls using XMM
 registers ("XMM Fast Hypercall Input"). When the feature is in use, it allows
 for faster hypercalls processing as KVM can avoid reading guest's memory.
 
+3.24. hv-tlbflush-ext
+=====================
+Allow for extended GVA ranges to be passed to Hyper-V TLB flush hypercalls
+(HvFlushVirtualAddressList/HvFlushVirtualAddressListEx).
+
+Requires: hv-tlbflush
+
 4. Supplementary features
 =========================
 

diff --git a/target/i386/cpu.c b/target/i386/cpu.c
index 63cec0ea68daf955cf08d095d97eef89311387a7..3429a4e455ab5e684f380dd8d674a381cf4a247d 100644 (file)
--- a/target/i386/cpu.c
+++ b/target/i386/cpu.c
@@ -6972,6 +6972,8 @@ static Property x86_cpu_properties[] = {
                       HYPERV_FEAT_MSR_BITMAP, 0),
     DEFINE_PROP_BIT64("hv-xmm-input", X86CPU, hyperv_features,
                       HYPERV_FEAT_XMM_INPUT, 0),
+    DEFINE_PROP_BIT64("hv-tlbflush-ext", X86CPU, hyperv_features,
+                      HYPERV_FEAT_TLBFLUSH_EXT, 0),
     DEFINE_PROP_ON_OFF_AUTO("hv-no-nonarch-coresharing", X86CPU,
                             hyperv_no_nonarch_cs, ON_OFF_AUTO_OFF),
     DEFINE_PROP_BIT64("hv-syndbg", X86CPU, hyperv_features,

diff --git a/target/i386/cpu.h b/target/i386/cpu.h
index 37e95535843b019308cccb55a72b1157eb7e9d0d..5ff48257e513f2502fdd62c3909bb00e6652a0a2 100644 (file)
--- a/target/i386/cpu.h
+++ b/target/i386/cpu.h
@@ -1108,6 +1108,7 @@ uint64_t x86_cpu_get_supported_feature_word(FeatureWord w,
 #define HYPERV_FEAT_SYNDBG              16
 #define HYPERV_FEAT_MSR_BITMAP          17
 #define HYPERV_FEAT_XMM_INPUT           18
+#define HYPERV_FEAT_TLBFLUSH_EXT        19
 
 #ifndef HYPERV_SPINLOCK_NEVER_NOTIFY
 #define HYPERV_SPINLOCK_NEVER_NOTIFY             0xFFFFFFFF

diff --git a/target/i386/kvm/hyperv-proto.h b/target/i386/kvm/hyperv-proto.h
index f5f16474fa2524be3aad04dc08dbc8ecf9e51f94..c7854ed6d306b8a58d303a3dc59d6db169a93809 100644 (file)
--- a/target/i386/kvm/hyperv-proto.h
+++ b/target/i386/kvm/hyperv-proto.h
@@ -59,6 +59,7 @@
 #define HV_FREQUENCY_MSRS_AVAILABLE             (1u << 8)
 #define HV_GUEST_CRASH_MSR_AVAILABLE            (1u << 10)
 #define HV_FEATURE_DEBUG_MSRS_AVAILABLE         (1u << 11)
+#define HV_EXT_GVA_RANGES_FLUSH_AVAILABLE       (1u << 14)
 #define HV_STIMER_DIRECT_MODE_AVAILABLE         (1u << 19)
 
 /*

diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c
index 7e6f934eda68f28330d4210f8f6cbc7425cdd77d..a11c8e88f6b273bfd1640ab15321b00128c4f91e 100644 (file)
--- a/target/i386/kvm/kvm.c
+++ b/target/i386/kvm/kvm.c
@@ -987,6 +987,14 @@ static struct {
              .bits = HV_HYPERCALL_XMM_INPUT_AVAILABLE}
         }
     },
+    [HYPERV_FEAT_TLBFLUSH_EXT] = {
+        .desc = "Extended gva ranges for TLB flush hypercalls (hv-tlbflush-ext)",
+        .flags = {
+            {.func = HV_CPUID_FEATURES, .reg = R_EDX,
+             .bits = HV_EXT_GVA_RANGES_FLUSH_AVAILABLE}
+        },
+        .dependencies = BIT(HYPERV_FEAT_TLBFLUSH)
+    },
 };
 
 static struct kvm_cpuid2 *try_get_hv_cpuid(CPUState *cs, int max,