xref: /freebsd/sys/amd64/vmm/intel/ept.c (revision f3754afd5901857787271e73f9c34d3b9069a03f)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
3  *
4  * Copyright (c) 2011 NetApp, Inc.
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY NETAPP, INC ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL NETAPP, INC OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/param.h>
30 #include <sys/kernel.h>
31 #include <sys/types.h>
32 #include <sys/systm.h>
33 #include <sys/smp.h>
34 #include <sys/sysctl.h>
35 
36 #include <vm/vm.h>
37 #include <vm/pmap.h>
38 #include <vm/vm_extern.h>
39 
40 #include <machine/vmm.h>
41 
42 #include "vmx_cpufunc.h"
43 #include "ept.h"
44 
45 #define	EPT_SUPPORTS_EXEC_ONLY(cap)	((cap) & (1UL << 0))
46 #define	EPT_PWL4(cap)			((cap) & (1UL << 6))
47 #define	EPT_MEMORY_TYPE_WB(cap)		((cap) & (1UL << 14))
48 #define	EPT_PDE_SUPERPAGE(cap)		((cap) & (1UL << 16))	/* 2MB pages */
49 #define	EPT_PDPTE_SUPERPAGE(cap)	((cap) & (1UL << 17))	/* 1GB pages */
50 #define	INVEPT_SUPPORTED(cap)		((cap) & (1UL << 20))
51 #define	AD_BITS_SUPPORTED(cap)		((cap) & (1UL << 21))
52 #define	INVVPID_SUPPORTED(cap)		((cap) & (1UL << 32))
53 
54 #define	INVVPID_ALL_TYPES_MASK		0xF0000000000UL
55 #define	INVVPID_ALL_TYPES_SUPPORTED(cap)	\
56 	(((cap) & INVVPID_ALL_TYPES_MASK) == INVVPID_ALL_TYPES_MASK)
57 
58 #define	INVEPT_ALL_TYPES_MASK		0x6000000UL
59 #define	INVEPT_ALL_TYPES_SUPPORTED(cap)		\
60 	(((cap) & INVEPT_ALL_TYPES_MASK) == INVEPT_ALL_TYPES_MASK)
61 
62 #define	EPT_PWLEVELS		4		/* page walk levels */
63 #define	EPT_ENABLE_AD_BITS	(1 << 6)
64 
65 SYSCTL_DECL(_hw_vmm);
66 SYSCTL_NODE(_hw_vmm, OID_AUTO, ept, CTLFLAG_RW | CTLFLAG_MPSAFE, NULL,
67     NULL);
68 
69 static int ept_enable_ad_bits;
70 
71 static int ept_pmap_flags;
72 SYSCTL_INT(_hw_vmm_ept, OID_AUTO, pmap_flags, CTLFLAG_RD,
73     &ept_pmap_flags, 0, NULL);
74 
75 int
ept_init(int ipinum)76 ept_init(int ipinum)
77 {
78 	int use_hw_ad_bits, use_superpages, use_exec_only;
79 	uint64_t cap;
80 
81 	cap = rdmsr(MSR_VMX_EPT_VPID_CAP);
82 
83 	/*
84 	 * Verify that:
85 	 * - page walk length is 4 steps
86 	 * - extended page tables can be laid out in write-back memory
87 	 * - invvpid instruction with all possible types is supported
88 	 * - invept instruction with all possible types is supported
89 	 */
90 	if (!EPT_PWL4(cap) ||
91 	    !EPT_MEMORY_TYPE_WB(cap) ||
92 	    !INVVPID_SUPPORTED(cap) ||
93 	    !INVVPID_ALL_TYPES_SUPPORTED(cap) ||
94 	    !INVEPT_SUPPORTED(cap) ||
95 	    !INVEPT_ALL_TYPES_SUPPORTED(cap))
96 		return (EINVAL);
97 
98 	ept_pmap_flags = ipinum & PMAP_NESTED_IPIMASK;
99 
100 	use_superpages = 1;
101 	TUNABLE_INT_FETCH("hw.vmm.ept.use_superpages", &use_superpages);
102 	if (use_superpages && EPT_PDE_SUPERPAGE(cap))
103 		ept_pmap_flags |= PMAP_PDE_SUPERPAGE;	/* 2MB superpage */
104 
105 	use_hw_ad_bits = 1;
106 	TUNABLE_INT_FETCH("hw.vmm.ept.use_hw_ad_bits", &use_hw_ad_bits);
107 	if (use_hw_ad_bits && AD_BITS_SUPPORTED(cap))
108 		ept_enable_ad_bits = 1;
109 	else
110 		ept_pmap_flags |= PMAP_EMULATE_AD_BITS;
111 
112 	use_exec_only = 1;
113 	TUNABLE_INT_FETCH("hw.vmm.ept.use_exec_only", &use_exec_only);
114 	if (use_exec_only && EPT_SUPPORTS_EXEC_ONLY(cap))
115 		ept_pmap_flags |= PMAP_SUPPORTS_EXEC_ONLY;
116 
117 	return (0);
118 }
119 
120 #if 0
121 static void
122 ept_dump(uint64_t *ptp, int nlevels)
123 {
124 	int i, t, tabs;
125 	uint64_t *ptpnext, ptpval;
126 
127 	if (--nlevels < 0)
128 		return;
129 
130 	tabs = 3 - nlevels;
131 	for (t = 0; t < tabs; t++)
132 		printf("\t");
133 	printf("PTP = %p\n", ptp);
134 
135 	for (i = 0; i < 512; i++) {
136 		ptpval = ptp[i];
137 
138 		if (ptpval == 0)
139 			continue;
140 
141 		for (t = 0; t < tabs; t++)
142 			printf("\t");
143 		printf("%3d 0x%016lx\n", i, ptpval);
144 
145 		if (nlevels != 0 && (ptpval & EPT_PG_SUPERPAGE) == 0) {
146 			ptpnext = (uint64_t *)
147 				  PHYS_TO_DMAP(ptpval & EPT_ADDR_MASK);
148 			ept_dump(ptpnext, nlevels);
149 		}
150 	}
151 }
152 #endif
153 
154 static void
invept_single_context(void * arg)155 invept_single_context(void *arg)
156 {
157 	struct invept_desc desc = *(struct invept_desc *)arg;
158 
159 	invept(INVEPT_TYPE_SINGLE_CONTEXT, desc);
160 }
161 
162 void
ept_invalidate_mappings(u_long eptp)163 ept_invalidate_mappings(u_long eptp)
164 {
165 	struct invept_desc invept_desc = { 0 };
166 
167 	invept_desc.eptp = eptp;
168 
169 	smp_rendezvous(NULL, invept_single_context, NULL, &invept_desc);
170 }
171 
172 static int
ept_pinit(pmap_t pmap)173 ept_pinit(pmap_t pmap)
174 {
175 
176 	return (pmap_pinit_type(pmap, PT_EPT, ept_pmap_flags));
177 }
178 
179 struct vmspace *
ept_vmspace_alloc(vm_offset_t min,vm_offset_t max)180 ept_vmspace_alloc(vm_offset_t min, vm_offset_t max)
181 {
182 
183 	return (vmspace_alloc(min, max, ept_pinit));
184 }
185 
186 void
ept_vmspace_free(struct vmspace * vmspace)187 ept_vmspace_free(struct vmspace *vmspace)
188 {
189 
190 	vmspace_free(vmspace);
191 }
192 
193 uint64_t
eptp(uint64_t pml4)194 eptp(uint64_t pml4)
195 {
196 	uint64_t eptp_val;
197 
198 	eptp_val = pml4 | (EPT_PWLEVELS - 1) << 3 | PAT_WRITE_BACK;
199 	if (ept_enable_ad_bits)
200 		eptp_val |= EPT_ENABLE_AD_BITS;
201 
202 	return (eptp_val);
203 }
204