target/i386/hvf/x86_descr.c

   1 /*
   2  * Copyright (C) 2016 Veertu Inc,
   3  * Copyright (C) 2017 Google Inc,
   4  *
   5  * This program is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2.1 of the License, or (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General Public
  16  * License along with this program; if not, see <http://www.gnu.org/licenses/>.
  17  */
  18
  19 #include "qemu/osdep.h"
  20
  21 #include "vmx.h"
  22 #include "x86_descr.h"
  23
  24 #define VMX_SEGMENT_FIELD(seg)                        \
  25     [R_##seg] = {                                     \
  26         .selector = VMCS_GUEST_##seg##_SELECTOR,      \
  27         .base = VMCS_GUEST_##seg##_BASE,              \
  28         .limit = VMCS_GUEST_##seg##_LIMIT,            \
  29         .ar_bytes = VMCS_GUEST_##seg##_ACCESS_RIGHTS, \
  30 }
  31
  32 static const struct vmx_segment_field {
  33     int selector;
  34     int base;
  35     int limit;
  36     int ar_bytes;
  37 } vmx_segment_fields[] = {
  38     VMX_SEGMENT_FIELD(ES),
  39     VMX_SEGMENT_FIELD(CS),
  40     VMX_SEGMENT_FIELD(SS),
  41     VMX_SEGMENT_FIELD(DS),
  42     VMX_SEGMENT_FIELD(FS),
  43     VMX_SEGMENT_FIELD(GS),
  44     VMX_SEGMENT_FIELD(LDTR),
  45     VMX_SEGMENT_FIELD(TR),
  46 };
  47
  48 uint32_t vmx_read_segment_limit(CPUState *cpu, X86Seg seg)
  49 {
  50     return (uint32_t)rvmcs(cpu->hvf->fd, vmx_segment_fields[seg].limit);
  51 }
  52
  53 uint32_t vmx_read_segment_ar(CPUState *cpu, X86Seg seg)
  54 {
  55     return (uint32_t)rvmcs(cpu->hvf->fd, vmx_segment_fields[seg].ar_bytes);
  56 }
  57
  58 uint64_t vmx_read_segment_base(CPUState *cpu, X86Seg seg)
  59 {
  60     return rvmcs(cpu->hvf->fd, vmx_segment_fields[seg].base);
  61 }
  62
  63 x68_segment_selector vmx_read_segment_selector(CPUState *cpu, X86Seg seg)
  64 {
  65     x68_segment_selector sel;
  66     sel.sel = rvmcs(cpu->hvf->fd, vmx_segment_fields[seg].selector);
  67     return sel;
  68 }
  69
  70 void vmx_write_segment_selector(struct CPUState *cpu, x68_segment_selector selector, X86Seg seg)
  71 {
  72     wvmcs(cpu->hvf->fd, vmx_segment_fields[seg].selector, selector.sel);
  73 }
  74
  75 void vmx_read_segment_descriptor(struct CPUState *cpu, struct vmx_segment *desc, X86Seg seg)
  76 {
  77     desc->sel = rvmcs(cpu->hvf->fd, vmx_segment_fields[seg].selector);
  78     desc->base = rvmcs(cpu->hvf->fd, vmx_segment_fields[seg].base);
  79     desc->limit = rvmcs(cpu->hvf->fd, vmx_segment_fields[seg].limit);
  80     desc->ar = rvmcs(cpu->hvf->fd, vmx_segment_fields[seg].ar_bytes);
  81 }
  82
  83 void vmx_write_segment_descriptor(CPUState *cpu, struct vmx_segment *desc, X86Seg seg)
  84 {
  85     const struct vmx_segment_field *sf = &vmx_segment_fields[seg];
  86
  87     wvmcs(cpu->hvf->fd, sf->base, desc->base);
  88     wvmcs(cpu->hvf->fd, sf->limit, desc->limit);
  89     wvmcs(cpu->hvf->fd, sf->selector, desc->sel);
  90     wvmcs(cpu->hvf->fd, sf->ar_bytes, desc->ar);
  91 }
  92
  93 void x86_segment_descriptor_to_vmx(struct CPUState *cpu, x68_segment_selector selector, struct x86_segment_descriptor *desc, struct vmx_segment *vmx_desc)
  94 {
  95     vmx_desc->sel = selector.sel;
  96     vmx_desc->base = x86_segment_base(desc);
  97     vmx_desc->limit = x86_segment_limit(desc);
  98
  99     vmx_desc->ar = (selector.sel ? 0 : 1) << 16 |
 100                     desc->g << 15 |
 101                     desc->db << 14 |
 102                     desc->l << 13 |
 103                     desc->avl << 12 |
 104                     desc->p << 7 |
 105                     desc->dpl << 5 |
 106                     desc->s << 4 |
 107                     desc->type;
 108 }
 109
 110 void vmx_segment_to_x86_descriptor(struct CPUState *cpu, struct vmx_segment *vmx_desc, struct x86_segment_descriptor *desc)
 111 {
 112     x86_set_segment_limit(desc, vmx_desc->limit);
 113     x86_set_segment_base(desc, vmx_desc->base);
 114
 115     desc->type = vmx_desc->ar & 15;
 116     desc->s = (vmx_desc->ar >> 4) & 1;
 117     desc->dpl = (vmx_desc->ar >> 5) & 3;
 118     desc->p = (vmx_desc->ar >> 7) & 1;
 119     desc->avl = (vmx_desc->ar >> 12) & 1;
 120     desc->l = (vmx_desc->ar >> 13) & 1;
 121     desc->db = (vmx_desc->ar >> 14) & 1;
 122     desc->g = (vmx_desc->ar >> 15) & 1;
 123 }
 124