Function vmcb_setdesc

freebsd/amd64/vmm/amd/vmcb.c:366–416

}

int
vmcb_setdesc(void *arg, int vcpu, int reg, struct seg_desc *desc)
{
	struct vmcb *vmcb;
	struct svm_softc *sc;
	struct vmcb_segment *seg;
	uint16_t attrib;

	sc = arg;
	vmcb = svm_get_vmcb(sc, vcpu);

	seg = vmcb_segptr(vmcb, reg);
	KASSERT(seg != NULL, ("%s: invalid segment descriptor %d",
	    __func__, reg));

	seg->base = desc->base;
	seg->limit = desc->limit;
	if (reg != VM_REG_GUEST_GDTR && reg != VM_REG_GUEST_IDTR) {
		/*
		 * Map seg_desc access to VMCB attribute format.
		 *
		 * SVM uses the 'P' bit in the segment attributes to indicate a
		 * NULL segment so clear it if the segment is marked unusable.
		 */
		attrib = ((desc->access & 0xF000) >> 4) | (desc->access & 0xFF);
		if (SEG_DESC_UNUSABLE(desc->access)) {
			attrib &= ~0x80;
		}
		seg->attrib = attrib;
	}

	VCPU_CTR4(sc->vm, vcpu, "Setting desc %d: base (%#lx), limit (%#x), "
	    "attrib (%#x)", reg, seg->base, seg->limit, seg->attrib);

	switch (reg) {
	case VM_REG_GUEST_CS:
	case VM_REG_GUEST_DS:
	case VM_REG_GUEST_ES:
	case VM_REG_GUEST_SS:
		svm_set_dirty(sc, vcpu, VMCB_CACHE_SEG);
		break;
	case VM_REG_GUEST_GDTR:
	case VM_REG_GUEST_IDTR:
		svm_set_dirty(sc, vcpu, VMCB_CACHE_DT);
		break;
	default:
		break;
	}

	return (0);
}

int
vmcb_getdesc(void *arg, int vcpu, int reg, struct seg_desc *desc)