xref: /freebsd/sys/amd64/vmm/intel/ept.c (revision f39bffc62c1395bde25d152c7f68fdf7cbaab414)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
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  * $FreeBSD$
29  */
30 
31 #include <sys/cdefs.h>
32 __FBSDID("$FreeBSD$");
33 
34 #include <sys/param.h>
35 #include <sys/kernel.h>
36 #include <sys/types.h>
37 #include <sys/systm.h>
38 #include <sys/smp.h>
39 #include <sys/sysctl.h>
40 
41 #include <vm/vm.h>
42 #include <vm/pmap.h>
43 #include <vm/vm_extern.h>
44 
45 #include <machine/vmm.h>
46 
47 #include "vmx_cpufunc.h"
48 #include "ept.h"
49 
50 #define	EPT_SUPPORTS_EXEC_ONLY(cap)	((cap) & (1UL << 0))
51 #define	EPT_PWL4(cap)			((cap) & (1UL << 6))
52 #define	EPT_MEMORY_TYPE_WB(cap)		((cap) & (1UL << 14))
53 #define	EPT_PDE_SUPERPAGE(cap)		((cap) & (1UL << 16))	/* 2MB pages */
54 #define	EPT_PDPTE_SUPERPAGE(cap)	((cap) & (1UL << 17))	/* 1GB pages */
55 #define	INVEPT_SUPPORTED(cap)		((cap) & (1UL << 20))
56 #define	AD_BITS_SUPPORTED(cap)		((cap) & (1UL << 21))
57 #define	INVVPID_SUPPORTED(cap)		((cap) & (1UL << 32))
58 
59 #define	INVVPID_ALL_TYPES_MASK		0xF0000000000UL
60 #define	INVVPID_ALL_TYPES_SUPPORTED(cap)	\
61 	(((cap) & INVVPID_ALL_TYPES_MASK) == INVVPID_ALL_TYPES_MASK)
62 
63 #define	INVEPT_ALL_TYPES_MASK		0x6000000UL
64 #define	INVEPT_ALL_TYPES_SUPPORTED(cap)		\
65 	(((cap) & INVEPT_ALL_TYPES_MASK) == INVEPT_ALL_TYPES_MASK)
66 
67 #define	EPT_PWLEVELS		4		/* page walk levels */
68 #define	EPT_ENABLE_AD_BITS	(1 << 6)
69 
70 SYSCTL_DECL(_hw_vmm);
71 SYSCTL_NODE(_hw_vmm, OID_AUTO, ept, CTLFLAG_RW, NULL, NULL);
72 
73 static int ept_enable_ad_bits;
74 
75 static int ept_pmap_flags;
76 SYSCTL_INT(_hw_vmm_ept, OID_AUTO, pmap_flags, CTLFLAG_RD,
77     &ept_pmap_flags, 0, NULL);
78 
79 int
80 ept_init(int ipinum)
81 {
82 	int use_hw_ad_bits, use_superpages, use_exec_only;
83 	uint64_t cap;
84 
85 	cap = rdmsr(MSR_VMX_EPT_VPID_CAP);
86 
87 	/*
88 	 * Verify that:
89 	 * - page walk length is 4 steps
90 	 * - extended page tables can be laid out in write-back memory
91 	 * - invvpid instruction with all possible types is supported
92 	 * - invept instruction with all possible types is supported
93 	 */
94 	if (!EPT_PWL4(cap) ||
95 	    !EPT_MEMORY_TYPE_WB(cap) ||
96 	    !INVVPID_SUPPORTED(cap) ||
97 	    !INVVPID_ALL_TYPES_SUPPORTED(cap) ||
98 	    !INVEPT_SUPPORTED(cap) ||
99 	    !INVEPT_ALL_TYPES_SUPPORTED(cap))
100 		return (EINVAL);
101 
102 	ept_pmap_flags = ipinum & PMAP_NESTED_IPIMASK;
103 
104 	use_superpages = 1;
105 	TUNABLE_INT_FETCH("hw.vmm.ept.use_superpages", &use_superpages);
106 	if (use_superpages && EPT_PDE_SUPERPAGE(cap))
107 		ept_pmap_flags |= PMAP_PDE_SUPERPAGE;	/* 2MB superpage */
108 
109 	use_hw_ad_bits = 1;
110 	TUNABLE_INT_FETCH("hw.vmm.ept.use_hw_ad_bits", &use_hw_ad_bits);
111 	if (use_hw_ad_bits && AD_BITS_SUPPORTED(cap))
112 		ept_enable_ad_bits = 1;
113 	else
114 		ept_pmap_flags |= PMAP_EMULATE_AD_BITS;
115 
116 	use_exec_only = 1;
117 	TUNABLE_INT_FETCH("hw.vmm.ept.use_exec_only", &use_exec_only);
118 	if (use_exec_only && EPT_SUPPORTS_EXEC_ONLY(cap))
119 		ept_pmap_flags |= PMAP_SUPPORTS_EXEC_ONLY;
120 
121 	return (0);
122 }
123 
124 #if 0
125 static void
126 ept_dump(uint64_t *ptp, int nlevels)
127 {
128 	int i, t, tabs;
129 	uint64_t *ptpnext, ptpval;
130 
131 	if (--nlevels < 0)
132 		return;
133 
134 	tabs = 3 - nlevels;
135 	for (t = 0; t < tabs; t++)
136 		printf("\t");
137 	printf("PTP = %p\n", ptp);
138 
139 	for (i = 0; i < 512; i++) {
140 		ptpval = ptp[i];
141 
142 		if (ptpval == 0)
143 			continue;
144 
145 		for (t = 0; t < tabs; t++)
146 			printf("\t");
147 		printf("%3d 0x%016lx\n", i, ptpval);
148 
149 		if (nlevels != 0 && (ptpval & EPT_PG_SUPERPAGE) == 0) {
150 			ptpnext = (uint64_t *)
151 				  PHYS_TO_DMAP(ptpval & EPT_ADDR_MASK);
152 			ept_dump(ptpnext, nlevels);
153 		}
154 	}
155 }
156 #endif
157 
158 static void
159 invept_single_context(void *arg)
160 {
161 	struct invept_desc desc = *(struct invept_desc *)arg;
162 
163 	invept(INVEPT_TYPE_SINGLE_CONTEXT, desc);
164 }
165 
166 void
167 ept_invalidate_mappings(u_long eptp)
168 {
169 	struct invept_desc invept_desc = { 0 };
170 
171 	invept_desc.eptp = eptp;
172 
173 	smp_rendezvous(NULL, invept_single_context, NULL, &invept_desc);
174 }
175 
176 static int
177 ept_pinit(pmap_t pmap)
178 {
179 
180 	return (pmap_pinit_type(pmap, PT_EPT, ept_pmap_flags));
181 }
182 
183 struct vmspace *
184 ept_vmspace_alloc(vm_offset_t min, vm_offset_t max)
185 {
186 
187 	return (vmspace_alloc(min, max, ept_pinit));
188 }
189 
190 void
191 ept_vmspace_free(struct vmspace *vmspace)
192 {
193 
194 	vmspace_free(vmspace);
195 }
196 
197 uint64_t
198 eptp(uint64_t pml4)
199 {
200 	uint64_t eptp_val;
201 
202 	eptp_val = pml4 | (EPT_PWLEVELS - 1) << 3 | PAT_WRITE_BACK;
203 	if (ept_enable_ad_bits)
204 		eptp_val |= EPT_ENABLE_AD_BITS;
205 
206 	return (eptp_val);
207 }
208