vmm(4): remove EPT mprotect ioctl

This old ioctl isn't used by vmd(8) and is getting in the way of some
improvements we want to do. It was used by solo5 but the person who was
helping maintain this is no longer involved with that project.

ok dv

2 files changed, 2 insertions, 263 deletions

diff --git a/sys/arch/amd64/amd64/vmm_machdep.c b/sys/arch/amd64/amd64/vmm_machdep.c
index 04944d513bf..c9a0531a67b 100644
--- a/sys/arch/amd64/amd64/vmm_machdep.c
+++ b/sys/arch/amd64/amd64/vmm_machdep.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: vmm_machdep.c,v 1.36 2024/09/04 16:12:40 dv Exp $ */
+/* $OpenBSD: vmm_machdep.c,v 1.37 2024/09/21 04:36:28 mlarkin Exp $ */
 /*
  * Copyright (c) 2014 Mike Larkin <mlarkin@openbsd.org>
  *
@@ -72,7 +72,6 @@ int vmm_quiesce_vmx(void);
 int vm_run(struct vm_run_params *);
 int vm_intr_pending(struct vm_intr_params *);
 int vm_rwregs(struct vm_rwregs_params *, int);
-int vm_mprotect_ept(struct vm_mprotect_ept_params *);
 int vm_rwvmparams(struct vm_rwvmparams_params *, int);
 int vcpu_readregs_vmx(struct vcpu *, uint64_t, int, struct vcpu_reg_state *);
 int vcpu_readregs_svm(struct vcpu *, uint64_t, struct vcpu_reg_state *);
@@ -125,7 +124,6 @@ int svm_fault_page(struct vcpu *, paddr_t);
 int vmx_fault_page(struct vcpu *, paddr_t);
 int vmx_handle_np_fault(struct vcpu *);
 int svm_handle_np_fault(struct vcpu *);
-int vmx_mprotect_ept(struct vcpu *, vm_map_t, paddr_t, paddr_t, int);
 pt_entry_t *vmx_pmap_find_pte_ept(pmap_t, paddr_t);
 int vmm_alloc_vpid(uint16_t *);
 void vmm_free_vpid(uint16_t);
@@ -440,9 +438,6 @@ vmmioctl_machdep(dev_t dev, u_long cmd, caddr_t data, int flag, struct proc *p)
 	case VMM_IOC_INTR:
 		ret = vm_intr_pending((struct vm_intr_params *)data);
 		break;
-	case VMM_IOC_MPROTECT_EPT:
-		ret = vm_mprotect_ept((struct vm_mprotect_ept_params *)data);
-		break;
 	default:
 		DPRINTF("%s: unknown ioctl code 0x%lx\n", __func__, cmd);
 		ret = ENOTTY;
@@ -456,7 +451,6 @@ pledge_ioctl_vmm_machdep(struct proc *p, long com)
 {
 	switch (com) {
 	case VMM_IOC_INTR:
-	case VMM_IOC_MPROTECT_EPT:
 		return (0);
 	}
 
@@ -625,250 +619,6 @@ out:
 }
 
 /*
- * vm_mprotect_ept
- *
- * IOCTL handler to sets the access protections of the ept
- *
- * Parameters:
- *   vmep: describes the memory for which the protect will be applied..
- *
- * Return values:
- *  0: if successful
- *  ENOENT: if the VM defined by 'vmep' cannot be found
- *  EINVAL: if the sgpa or size is not page aligned, the prot is invalid,
- *          size is too large (512GB), there is wraparound
- *          (like start = 512GB-1 and end = 512GB-2),
- *          the address specified is not within the vm's mem range
- *          or the address lies inside reserved (MMIO) memory
- */
-int
-vm_mprotect_ept(struct vm_mprotect_ept_params *vmep)
-{
-	struct vm *vm;
-	struct vcpu *vcpu;
-	vaddr_t sgpa;
-	size_t size;
-	vm_prot_t prot;
-	uint64_t msr;
-	int ret = 0, memtype;
-
-	/* If not EPT or RVI, nothing to do here */
-	if (!(vmm_softc->mode == VMM_MODE_EPT
-	    || vmm_softc->mode == VMM_MODE_RVI))
-		return (0);
-
-	/* Find the desired VM */
-	ret = vm_find(vmep->vmep_vm_id, &vm);
-
-	/* Not found? exit. */
-	if (ret != 0) {
-		DPRINTF("%s: vm id %u not found\n", __func__,
-		    vmep->vmep_vm_id);
-		return (ret);
-	}
-
-	vcpu = vm_find_vcpu(vm, vmep->vmep_vcpu_id);
-
-	if (vcpu == NULL) {
-		DPRINTF("%s: vcpu id %u of vm %u not found\n", __func__,
-		    vmep->vmep_vcpu_id, vmep->vmep_vm_id);
-		ret = ENOENT;
-		goto out_nolock;
-	}
-
-	rw_enter_write(&vcpu->vc_lock);
-
-	if (vcpu->vc_state != VCPU_STATE_STOPPED) {
-		DPRINTF("%s: mprotect_ept %u on vm %u attempted "
-		    "while vcpu was in state %u (%s)\n", __func__,
-		    vmep->vmep_vcpu_id, vmep->vmep_vm_id, vcpu->vc_state,
-		    vcpu_state_decode(vcpu->vc_state));
-		ret = EBUSY;
-		goto out;
-	}
-
-	/* Only proceed if the pmap is in the correct mode */
-	KASSERT((vmm_softc->mode == VMM_MODE_EPT &&
-	    vm->vm_map->pmap->pm_type == PMAP_TYPE_EPT) ||
-	    (vmm_softc->mode == VMM_MODE_RVI &&
-	     vm->vm_map->pmap->pm_type == PMAP_TYPE_RVI));
-
-	sgpa = vmep->vmep_sgpa;
-	size = vmep->vmep_size;
-	prot = vmep->vmep_prot;
-
-	/* No W^X permissions */
-	if ((prot & PROT_MASK) != prot &&
-	    (prot & (PROT_WRITE | PROT_EXEC)) == (PROT_WRITE | PROT_EXEC)) {
-		DPRINTF("%s: W+X permission requested\n", __func__);
-		ret = EINVAL;
-		goto out;
-	}
-
-	/* No Write only permissions */
-	if ((prot & (PROT_READ | PROT_WRITE | PROT_EXEC)) == PROT_WRITE) {
-		DPRINTF("%s: No Write only permissions\n", __func__);
-		ret = EINVAL;
-		goto out;
-	}
-
-	/* No empty permissions */
-	if (prot == 0) {
-		DPRINTF("%s: No empty permissions\n", __func__);
-		ret = EINVAL;
-		goto out;
-	}
-
-	/* No execute only on EPT CPUs that don't have that capability */
-	if (vmm_softc->mode == VMM_MODE_EPT) {
-		msr = rdmsr(IA32_VMX_EPT_VPID_CAP);
-		if (prot == PROT_EXEC &&
-		    (msr & IA32_EPT_VPID_CAP_XO_TRANSLATIONS) == 0) {
-			DPRINTF("%s: Execute only permissions unsupported,"
-			   " adding read permission\n", __func__);
-
-			prot |= PROT_READ;
-		}
-	}
-
-	/* Must be page aligned */
-	if ((sgpa & PAGE_MASK) || (size & PAGE_MASK) || size == 0) {
-		ret = EINVAL;
-		goto out;
-	}
-
-	/* size must be less then 512GB */
-	if (size >= NBPD_L4) {
-		ret = EINVAL;
-		goto out;
-	}
-
-	/* no wraparound */
-	if (sgpa + size < sgpa) {
-		ret = EINVAL;
-		goto out;
-	}
-
-	/*
-	 * Specifying addresses within the PCI MMIO space is forbidden.
-	 * Disallow addresses that start inside the MMIO space:
-	 * [VMM_PCI_MMIO_BAR_BASE .. VMM_PCI_MMIO_BAR_END]
-	 */
-	if (sgpa >= VMM_PCI_MMIO_BAR_BASE && sgpa <= VMM_PCI_MMIO_BAR_END) {
-		ret = EINVAL;
-		goto out;
-	}
-
-	/*
-	 * ... and disallow addresses that end inside the MMIO space:
-	 * (VMM_PCI_MMIO_BAR_BASE .. VMM_PCI_MMIO_BAR_END]
-	 */
-	if (sgpa + size > VMM_PCI_MMIO_BAR_BASE &&
-	    sgpa + size <= VMM_PCI_MMIO_BAR_END) {
-		ret = EINVAL;
-		goto out;
-	}
-
-	memtype = vmm_get_guest_memtype(vm, sgpa);
-	if (memtype == VMM_MEM_TYPE_UNKNOWN) {
-		ret = EINVAL;
-		goto out;
-	}
-
-	if (vmm_softc->mode == VMM_MODE_EPT)
-		ret = vmx_mprotect_ept(vcpu, vm->vm_map, sgpa, sgpa + size,
-		    prot);
-	else if (vmm_softc->mode == VMM_MODE_RVI) {
-		pmap_write_protect(vm->vm_map->pmap, sgpa, sgpa + size, prot);
-		/* XXX requires a invlpga */
-		ret = 0;
-	} else
-		ret = EINVAL;
-out:
-	if (vcpu != NULL)
-		rw_exit_write(&vcpu->vc_lock);
-out_nolock:
-	refcnt_rele_wake(&vm->vm_refcnt);
-	return (ret);
-}
-
-/*
- * vmx_mprotect_ept
- *
- * apply the ept protections to the requested pages, faulting in the page if
- * required.
- */
-int
-vmx_mprotect_ept(struct vcpu *vcpu, vm_map_t vm_map, paddr_t sgpa, paddr_t egpa,
-    int prot)
-{
-	struct vmx_invept_descriptor vid;
-	pmap_t pmap;
-	pt_entry_t *pte;
-	paddr_t addr;
-	int ret = 0;
-
-	pmap = vm_map->pmap;
-
-	KERNEL_LOCK();
-
-	for (addr = sgpa; addr < egpa; addr += PAGE_SIZE) {
-		pte = vmx_pmap_find_pte_ept(pmap, addr);
-		if (pte == NULL) {
-			ret = uvm_fault(vm_map, addr, VM_FAULT_WIRE,
-			    PROT_READ | PROT_WRITE | PROT_EXEC);
-			if (ret)
-				printf("%s: uvm_fault returns %d, GPA=0x%llx\n",
-				    __func__, ret, (uint64_t)addr);
-
-			pte = vmx_pmap_find_pte_ept(pmap, addr);
-			if (pte == NULL) {
-				KERNEL_UNLOCK();
-				return EFAULT;
-			}
-		}
-
-		if (prot & PROT_READ)
-			*pte |= EPT_R;
-		else
-			*pte &= ~EPT_R;
-
-		if (prot & PROT_WRITE)
-			*pte |= EPT_W;
-		else
-			*pte &= ~EPT_W;
-
-		if (prot & PROT_EXEC)
-			*pte |= EPT_X;
-		else
-			*pte &= ~EPT_X;
-	}
-
-	/*
-	 * SDM 3C: 28.3.3.4 Guidelines for Use of the INVEPT Instruction
-	 * the first bullet point seems to say we should call invept.
-	 *
-	 * Software should use the INVEPT instruction with the “single-context”
-	 * INVEPT type after making any of the following changes to an EPT
-	 * paging-structure entry (the INVEPT descriptor should contain an
-	 * EPTP value that references — directly or indirectly
-	 * — the modified EPT paging structure):
-	 * —   Changing any of the privilege bits 2:0 from 1 to 0.
-	 * */
-	if (pmap->eptp != 0) {
-		memset(&vid, 0, sizeof(vid));
-		vid.vid_eptp = pmap->eptp;
-		DPRINTF("%s: flushing EPT TLB for EPTP 0x%llx\n", __func__,
-		    vid.vid_eptp);
-		invept(vcpu->vc_vmx_invept_op, &vid);
-	}
-
-	KERNEL_UNLOCK();
-
-	return ret;
-}
-
-/*
  * vmx_pmap_find_pte_ept
  *
  * find the page table entry specified by addr in the pmap supplied.
diff --git a/sys/arch/amd64/include/vmmvar.h b/sys/arch/amd64/include/vmmvar.h
index f652bc1b83f..c607c1d663a 100644
--- a/sys/arch/amd64/include/vmmvar.h
+++ b/sys/arch/amd64/include/vmmvar.h
@@ -1,4 +1,4 @@
-/*	$OpenBSD: vmmvar.h,v 1.105 2024/08/27 09:16:03 bluhm Exp $	*/
+/*	$OpenBSD: vmmvar.h,v 1.106 2024/09/21 04:36:28 mlarkin Exp $	*/
 /*
  * Copyright (c) 2014 Mike Larkin <mlarkin@openbsd.org>
  *
@@ -492,19 +492,8 @@ struct vm_rwregs_params {
 	struct vcpu_reg_state	vrwp_regs;
 };
 
-struct vm_mprotect_ept_params {
-	/* Input parameters to VMM_IOC_MPROTECT_EPT */
-	uint32_t		vmep_vm_id;
-	uint32_t		vmep_vcpu_id;
-	vaddr_t			vmep_sgpa;
-	size_t			vmep_size;
-	int			vmep_prot;
-};
-
 /* IOCTL definitions */
 #define VMM_IOC_INTR _IOW('V', 6, struct vm_intr_params) /* Intr pending */
-/* Control the protection of ept pages*/
-#define VMM_IOC_MPROTECT_EPT _IOW('V', 11, struct vm_mprotect_ept_params)
 
 /* CPUID masks */
 /*