target/i386/mshv: hv_vp_register_page setup for the vcpu
When the vcpu is created, call mmap to configure access to the register page. Update CPUArchState to store a pointer to the mmapped hv_vp_register_page. Signed-off-by: Doru Blânzeanu <dblanzeanu@linux.microsoft.com> Reviewed-by: Mohamed Mediouni <mohamed@unpredictable.fr> Link: https://lore.kernel.org/r/20260428135053.251200-5-dblanzeanu@linux.microsoft.com Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Doru Blânzeanu committed
Apr 28, 2026 at 16:50 UTC
a173f8f17001907ee41badcc9ceb824113bc0da4
2 files changed
+24
-2
target/i386/cpu.h
+7
-2
@@ -1983,6 +1983,9 @@ typedef struct CPUCaches {
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CPUCacheInfo *l3_cache;
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} CPUCaches;
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+struct kvm_msrs;
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+struct hv_vp_register_page;
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+
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typedef struct CPUArchState {
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/* standard registers */
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target_ulong regs[CPU_NB_EREGS];
@@ -2289,6 +2292,10 @@ typedef struct CPUArchState {
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QEMUTimer *xen_periodic_timer;
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QemuMutex xen_timers_lock;
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#endif
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+#if defined(CONFIG_MSHV)
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+ /* Shared register page */
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+ struct hv_vp_register_page *regs_page;
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+#endif
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#if defined(CONFIG_HVF) || defined(CONFIG_MSHV) || defined(CONFIG_WHPX)
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void *emu_mmio_buf;
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#endif
@@ -2315,8 +2322,6 @@ typedef struct CPUArchState {
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DECLARE_BITMAP(avail_cpu_topo, CPU_TOPOLOGY_LEVEL__MAX);
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} CPUX86State;
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-struct kvm_msrs;
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-
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/**
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* X86CPU:
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* @env: #CPUX86State
target/i386/mshv/mshv-cpu.c
+17
@@ -1906,6 +1906,18 @@ void mshv_arch_init_vcpu(CPUState *cpu)
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+ sizeof(hv_input_get_vp_registers)
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> HV_HYP_PAGE_SIZE));
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+ /* mmap the registers page */
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+ void *rp = mmap(NULL, page, PROT_READ | PROT_WRITE,
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+ MAP_SHARED, mshv_vcpufd(cpu),
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+ MSHV_VP_MMAP_OFFSET_REGISTERS * page);
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+ if (rp == MAP_FAILED) {
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+ warn_report("register page mmap failed, falling back to hypercalls: %s",
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+ strerror(errno));
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+ env->regs_page = NULL;
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+ } else {
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+ env->regs_page = (struct hv_vp_register_page *) rp;
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+ }
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+
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state->hvcall_args.base = mem;
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state->hvcall_args.input_page = mem;
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state->hvcall_args.output_page = (uint8_t *)mem + page;
@@ -1944,6 +1956,11 @@ void mshv_arch_destroy_vcpu(CPUState *cpu)
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CPUX86State *env = &x86_cpu->env;
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AccelCPUState *state = cpu->accel;
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+ /* Unmap the register page */
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+ if (env->regs_page) {
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+ munmap(env->regs_page, HV_HYP_PAGE_SIZE);
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+ env->regs_page = NULL;
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+ }
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g_free(state->hvcall_args.base);
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state->hvcall_args = (MshvHvCallArgs){0};
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g_clear_pointer(&env->emu_mmio_buf, g_free);