35 lines
		
	
	
		
			872 B
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			35 lines
		
	
	
		
			872 B
		
	
	
	
		
			C
		
	
	
	
	
	
| // SPDX-License-Identifier: GPL-2.0
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| /*
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|  * ucall support. A ucall is a "hypercall to userspace".
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|  *
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|  * Copyright (C) 2018, Red Hat, Inc.
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|  */
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| #include "kvm_util.h"
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| 
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| vm_vaddr_t *ucall_exit_mmio_addr;
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| 
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| void ucall_arch_init(struct kvm_vm *vm, vm_paddr_t mmio_gpa)
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| {
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| 	vm_vaddr_t mmio_gva = vm_vaddr_unused_gap(vm, vm->page_size, KVM_UTIL_MIN_VADDR);
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| 
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| 	virt_map(vm, mmio_gva, mmio_gpa, 1);
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| 
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| 	vm->ucall_mmio_addr = mmio_gpa;
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| 
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| 	write_guest_global(vm, ucall_exit_mmio_addr, (vm_vaddr_t *)mmio_gva);
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| }
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| 
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| void *ucall_arch_get_ucall(struct kvm_vcpu *vcpu)
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| {
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| 	struct kvm_run *run = vcpu->run;
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| 
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| 	if (run->exit_reason == KVM_EXIT_MMIO &&
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| 	    run->mmio.phys_addr == vcpu->vm->ucall_mmio_addr) {
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| 		TEST_ASSERT(run->mmio.is_write && run->mmio.len == sizeof(uint64_t),
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| 			    "Unexpected ucall exit mmio address access");
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| 		return (void *)(*((uint64_t *)run->mmio.data));
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| 	}
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| 
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| 	return NULL;
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| }
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