1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2012 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 #ifndef _VMM_INSTRUCTION_EMUL_H_ 32 #define _VMM_INSTRUCTION_EMUL_H_ 33 34 #include <sys/mman.h> 35 36 /* 37 * Callback functions to read and write memory regions. 38 */ 39 typedef int (*mem_region_read_t)(struct vcpu *vcpu, uint64_t gpa, 40 uint64_t *rval, int rsize, void *arg); 41 42 typedef int (*mem_region_write_t)(struct vcpu *vcpu, uint64_t gpa, 43 uint64_t wval, int wsize, void *arg); 44 45 /* 46 * Emulate the decoded 'vie' instruction. 47 * 48 * The callbacks 'mrr' and 'mrw' emulate reads and writes to the memory region 49 * containing 'gpa'. 'mrarg' is an opaque argument that is passed into the 50 * callback functions. 51 * 52 * 'void *vm' should be 'struct vm *' when called from kernel context and 53 * 'struct vmctx *' when called from user context. 54 * s 55 */ 56 int vmm_emulate_instruction(struct vcpu *vcpu, uint64_t gpa, struct vie *vie, 57 struct vm_guest_paging *paging, mem_region_read_t mrr, 58 mem_region_write_t mrw, void *mrarg); 59 60 int vie_update_register(struct vcpu *vcpu, enum vm_reg_name reg, 61 uint64_t val, int size); 62 63 /* 64 * Returns 1 if an alignment check exception should be injected and 0 otherwise. 65 */ 66 int vie_alignment_check(int cpl, int operand_size, uint64_t cr0, 67 uint64_t rflags, uint64_t gla); 68 69 /* Returns 1 if the 'gla' is not canonical and 0 otherwise. */ 70 int vie_canonical_check(enum vm_cpu_mode cpu_mode, uint64_t gla); 71 72 uint64_t vie_size2mask(int size); 73 74 int vie_calculate_gla(enum vm_cpu_mode cpu_mode, enum vm_reg_name seg, 75 struct seg_desc *desc, uint64_t off, int length, int addrsize, int prot, 76 uint64_t *gla); 77 78 #ifdef _KERNEL 79 /* 80 * APIs to fetch and decode the instruction from nested page fault handler. 81 * 82 * 'vie' must be initialized before calling 'vmm_fetch_instruction()' 83 */ 84 int vmm_fetch_instruction(struct vcpu *vcpu, 85 struct vm_guest_paging *guest_paging, 86 uint64_t rip, int inst_length, struct vie *vie, 87 int *is_fault); 88 89 /* 90 * Translate the guest linear address 'gla' to a guest physical address. 91 * 92 * retval is_fault Interpretation 93 * 0 0 'gpa' contains result of the translation 94 * 0 1 An exception was injected into the guest 95 * EFAULT N/A An unrecoverable hypervisor error occurred 96 */ 97 int vm_gla2gpa(struct vcpu *vcpu, struct vm_guest_paging *paging, 98 uint64_t gla, int prot, uint64_t *gpa, int *is_fault); 99 100 /* 101 * Like vm_gla2gpa, but no exceptions are injected into the guest and 102 * PTEs are not changed. 103 */ 104 int vm_gla2gpa_nofault(struct vcpu *vcpu, struct vm_guest_paging *paging, 105 uint64_t gla, int prot, uint64_t *gpa, int *is_fault); 106 #endif /* _KERNEL */ 107 108 void vie_restart(struct vie *vie); 109 void vie_init(struct vie *vie, const char *inst_bytes, int inst_length); 110 111 /* 112 * Decode the instruction fetched into 'vie' so it can be emulated. 113 * 114 * 'gla' is the guest linear address provided by the hardware assist 115 * that caused the nested page table fault. It is used to verify that 116 * the software instruction decoding is in agreement with the hardware. 117 * 118 * Some hardware assists do not provide the 'gla' to the hypervisor. 119 * To skip the 'gla' verification for this or any other reason pass 120 * in VIE_INVALID_GLA instead. 121 */ 122 #ifdef _KERNEL 123 #define VIE_INVALID_GLA (1UL << 63) /* a non-canonical address */ 124 int vmm_decode_instruction(struct vcpu *vcpu, uint64_t gla, 125 enum vm_cpu_mode cpu_mode, int csd, struct vie *vie); 126 #else /* !_KERNEL */ 127 /* 128 * Permit instruction decoding logic to be compiled outside of the kernel for 129 * rapid iteration and validation. No GLA validation is performed, obviously. 130 */ 131 int vmm_decode_instruction(enum vm_cpu_mode cpu_mode, int csd, 132 struct vie *vie); 133 #endif /* _KERNEL */ 134 135 #endif /* _VMM_INSTRUCTION_EMUL_H_ */ 136