xref: /freebsd/sys/amd64/vmm/intel/ept.c (revision 7ef62cebc2f965b0f640263e179276928885e33d)
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  * $FreeBSD$
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 | CTLFLAG_MPSAFE, NULL,
72     NULL);
73 
74 static int ept_enable_ad_bits;
75 
76 static int ept_pmap_flags;
77 SYSCTL_INT(_hw_vmm_ept, OID_AUTO, pmap_flags, CTLFLAG_RD,
78     &ept_pmap_flags, 0, NULL);
79 
80 int
81 ept_init(int ipinum)
82 {
83 	int use_hw_ad_bits, use_superpages, use_exec_only;
84 	uint64_t cap;
85 
86 	cap = rdmsr(MSR_VMX_EPT_VPID_CAP);
87 
88 	/*
89 	 * Verify that:
90 	 * - page walk length is 4 steps
91 	 * - extended page tables can be laid out in write-back memory
92 	 * - invvpid instruction with all possible types is supported
93 	 * - invept instruction with all possible types is supported
94 	 */
95 	if (!EPT_PWL4(cap) ||
96 	    !EPT_MEMORY_TYPE_WB(cap) ||
97 	    !INVVPID_SUPPORTED(cap) ||
98 	    !INVVPID_ALL_TYPES_SUPPORTED(cap) ||
99 	    !INVEPT_SUPPORTED(cap) ||
100 	    !INVEPT_ALL_TYPES_SUPPORTED(cap))
101 		return (EINVAL);
102 
103 	ept_pmap_flags = ipinum & PMAP_NESTED_IPIMASK;
104 
105 	use_superpages = 1;
106 	TUNABLE_INT_FETCH("hw.vmm.ept.use_superpages", &use_superpages);
107 	if (use_superpages && EPT_PDE_SUPERPAGE(cap))
108 		ept_pmap_flags |= PMAP_PDE_SUPERPAGE;	/* 2MB superpage */
109 
110 	use_hw_ad_bits = 1;
111 	TUNABLE_INT_FETCH("hw.vmm.ept.use_hw_ad_bits", &use_hw_ad_bits);
112 	if (use_hw_ad_bits && AD_BITS_SUPPORTED(cap))
113 		ept_enable_ad_bits = 1;
114 	else
115 		ept_pmap_flags |= PMAP_EMULATE_AD_BITS;
116 
117 	use_exec_only = 1;
118 	TUNABLE_INT_FETCH("hw.vmm.ept.use_exec_only", &use_exec_only);
119 	if (use_exec_only && EPT_SUPPORTS_EXEC_ONLY(cap))
120 		ept_pmap_flags |= PMAP_SUPPORTS_EXEC_ONLY;
121 
122 	return (0);
123 }
124 
125 #if 0
126 static void
127 ept_dump(uint64_t *ptp, int nlevels)
128 {
129 	int i, t, tabs;
130 	uint64_t *ptpnext, ptpval;
131 
132 	if (--nlevels < 0)
133 		return;
134 
135 	tabs = 3 - nlevels;
136 	for (t = 0; t < tabs; t++)
137 		printf("\t");
138 	printf("PTP = %p\n", ptp);
139 
140 	for (i = 0; i < 512; i++) {
141 		ptpval = ptp[i];
142 
143 		if (ptpval == 0)
144 			continue;
145 
146 		for (t = 0; t < tabs; t++)
147 			printf("\t");
148 		printf("%3d 0x%016lx\n", i, ptpval);
149 
150 		if (nlevels != 0 && (ptpval & EPT_PG_SUPERPAGE) == 0) {
151 			ptpnext = (uint64_t *)
152 				  PHYS_TO_DMAP(ptpval & EPT_ADDR_MASK);
153 			ept_dump(ptpnext, nlevels);
154 		}
155 	}
156 }
157 #endif
158 
159 static void
160 invept_single_context(void *arg)
161 {
162 	struct invept_desc desc = *(struct invept_desc *)arg;
163 
164 	invept(INVEPT_TYPE_SINGLE_CONTEXT, desc);
165 }
166 
167 void
168 ept_invalidate_mappings(u_long eptp)
169 {
170 	struct invept_desc invept_desc = { 0 };
171 
172 	invept_desc.eptp = eptp;
173 
174 	smp_rendezvous(NULL, invept_single_context, NULL, &invept_desc);
175 }
176 
177 static int
178 ept_pinit(pmap_t pmap)
179 {
180 
181 	return (pmap_pinit_type(pmap, PT_EPT, ept_pmap_flags));
182 }
183 
184 struct vmspace *
185 ept_vmspace_alloc(vm_offset_t min, vm_offset_t max)
186 {
187 
188 	return (vmspace_alloc(min, max, ept_pinit));
189 }
190 
191 void
192 ept_vmspace_free(struct vmspace *vmspace)
193 {
194 
195 	vmspace_free(vmspace);
196 }
197 
198 uint64_t
199 eptp(uint64_t pml4)
200 {
201 	uint64_t eptp_val;
202 
203 	eptp_val = pml4 | (EPT_PWLEVELS - 1) << 3 | PAT_WRITE_BACK;
204 	if (ept_enable_ad_bits)
205 		eptp_val |= EPT_ENABLE_AD_BITS;
206 
207 	return (eptp_val);
208 }
209