arch/arm64/kvm/regmap.c

   1 /*
   2  * Copyright (C) 2012,2013 - ARM Ltd
   3  * Author: Marc Zyngier <marc.zyngier@arm.com>
   4  *
   5  * Derived from arch/arm/kvm/emulate.c:
   6  * Copyright (C) 2012 - Virtual Open Systems and Columbia University
   7  * Author: Christoffer Dall <c.dall@virtualopensystems.com>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2 as
  11  * published by the Free Software Foundation.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  20  */
  21
  22 #include <linux/mm.h>
  23 #include <linux/kvm_host.h>
  24 #include <asm/kvm_emulate.h>
  25 #include <asm/ptrace.h>
  26
  27 #define VCPU_NR_MODES 6
  28 #define REG_OFFSET(_reg) \
  29         (offsetof(struct user_pt_regs, _reg) / sizeof(unsigned long))
  30
  31 #define USR_REG_OFFSET(R) REG_OFFSET(compat_usr(R))
  32
  33 static const unsigned long vcpu_reg_offsets[VCPU_NR_MODES][16] = {
  34         /* USR Registers */
  35         {
  36                 USR_REG_OFFSET(0), USR_REG_OFFSET(1), USR_REG_OFFSET(2),
  37                 USR_REG_OFFSET(3), USR_REG_OFFSET(4), USR_REG_OFFSET(5),
  38                 USR_REG_OFFSET(6), USR_REG_OFFSET(7), USR_REG_OFFSET(8),
  39                 USR_REG_OFFSET(9), USR_REG_OFFSET(10), USR_REG_OFFSET(11),
  40                 USR_REG_OFFSET(12), USR_REG_OFFSET(13), USR_REG_OFFSET(14),
  41                 REG_OFFSET(pc)
  42         },
  43
  44         /* FIQ Registers */
  45         {
  46                 USR_REG_OFFSET(0), USR_REG_OFFSET(1), USR_REG_OFFSET(2),
  47                 USR_REG_OFFSET(3), USR_REG_OFFSET(4), USR_REG_OFFSET(5),
  48                 USR_REG_OFFSET(6), USR_REG_OFFSET(7),
  49                 REG_OFFSET(compat_r8_fiq),  /* r8 */
  50                 REG_OFFSET(compat_r9_fiq),  /* r9 */
  51                 REG_OFFSET(compat_r10_fiq), /* r10 */
  52                 REG_OFFSET(compat_r11_fiq), /* r11 */
  53                 REG_OFFSET(compat_r12_fiq), /* r12 */
  54                 REG_OFFSET(compat_sp_fiq),  /* r13 */
  55                 REG_OFFSET(compat_lr_fiq),  /* r14 */
  56                 REG_OFFSET(pc)
  57         },
  58
  59         /* IRQ Registers */
  60         {
  61                 USR_REG_OFFSET(0), USR_REG_OFFSET(1), USR_REG_OFFSET(2),
  62                 USR_REG_OFFSET(3), USR_REG_OFFSET(4), USR_REG_OFFSET(5),
  63                 USR_REG_OFFSET(6), USR_REG_OFFSET(7), USR_REG_OFFSET(8),
  64                 USR_REG_OFFSET(9), USR_REG_OFFSET(10), USR_REG_OFFSET(11),
  65                 USR_REG_OFFSET(12),
  66                 REG_OFFSET(compat_sp_irq), /* r13 */
  67                 REG_OFFSET(compat_lr_irq), /* r14 */
  68                 REG_OFFSET(pc)
  69         },
  70
  71         /* SVC Registers */
  72         {
  73                 USR_REG_OFFSET(0), USR_REG_OFFSET(1), USR_REG_OFFSET(2),
  74                 USR_REG_OFFSET(3), USR_REG_OFFSET(4), USR_REG_OFFSET(5),
  75                 USR_REG_OFFSET(6), USR_REG_OFFSET(7), USR_REG_OFFSET(8),
  76                 USR_REG_OFFSET(9), USR_REG_OFFSET(10), USR_REG_OFFSET(11),
  77                 USR_REG_OFFSET(12),
  78                 REG_OFFSET(compat_sp_svc), /* r13 */
  79                 REG_OFFSET(compat_lr_svc), /* r14 */
  80                 REG_OFFSET(pc)
  81         },
  82
  83         /* ABT Registers */
  84         {
  85                 USR_REG_OFFSET(0), USR_REG_OFFSET(1), USR_REG_OFFSET(2),
  86                 USR_REG_OFFSET(3), USR_REG_OFFSET(4), USR_REG_OFFSET(5),
  87                 USR_REG_OFFSET(6), USR_REG_OFFSET(7), USR_REG_OFFSET(8),
  88                 USR_REG_OFFSET(9), USR_REG_OFFSET(10), USR_REG_OFFSET(11),
  89                 USR_REG_OFFSET(12),
  90                 REG_OFFSET(compat_sp_abt), /* r13 */
  91                 REG_OFFSET(compat_lr_abt), /* r14 */
  92                 REG_OFFSET(pc)
  93         },
  94
  95         /* UND Registers */
  96         {
  97                 USR_REG_OFFSET(0), USR_REG_OFFSET(1), USR_REG_OFFSET(2),
  98                 USR_REG_OFFSET(3), USR_REG_OFFSET(4), USR_REG_OFFSET(5),
  99                 USR_REG_OFFSET(6), USR_REG_OFFSET(7), USR_REG_OFFSET(8),
 100                 USR_REG_OFFSET(9), USR_REG_OFFSET(10), USR_REG_OFFSET(11),
 101                 USR_REG_OFFSET(12),
 102                 REG_OFFSET(compat_sp_und), /* r13 */
 103                 REG_OFFSET(compat_lr_und), /* r14 */
 104                 REG_OFFSET(pc)
 105         },
 106 };
 107
 108 /*
 109  * Return a pointer to the register number valid in the current mode of
 110  * the virtual CPU.
 111  */
 112 unsigned long *vcpu_reg32(const struct kvm_vcpu *vcpu, u8 reg_num)
 113 {
 114         unsigned long *reg_array = (unsigned long *)&vcpu->arch.ctxt.gp_regs.regs;
 115         unsigned long mode = *vcpu_cpsr(vcpu) & COMPAT_PSR_MODE_MASK;
 116
 117         switch (mode) {
 118         case COMPAT_PSR_MODE_USR ... COMPAT_PSR_MODE_SVC:
 119                 mode &= ~PSR_MODE32_BIT; /* 0 ... 3 */
 120                 break;
 121
 122         case COMPAT_PSR_MODE_ABT:
 123                 mode = 4;
 124                 break;
 125
 126         case COMPAT_PSR_MODE_UND:
 127                 mode = 5;
 128                 break;
 129
 130         case COMPAT_PSR_MODE_SYS:
 131                 mode = 0;       /* SYS maps to USR */
 132                 break;
 133
 134         default:
 135                 BUG();
 136         }
 137
 138         return reg_array + vcpu_reg_offsets[mode][reg_num];
 139 }
 140
 141 /*
 142  * Return the SPSR for the current mode of the virtual CPU.
 143  */
 144 static int vcpu_spsr32_mode(const struct kvm_vcpu *vcpu)
 145 {
 146         unsigned long mode = *vcpu_cpsr(vcpu) & COMPAT_PSR_MODE_MASK;
 147         switch (mode) {
 148         case COMPAT_PSR_MODE_SVC: return KVM_SPSR_SVC;
 149         case COMPAT_PSR_MODE_ABT: return KVM_SPSR_ABT;
 150         case COMPAT_PSR_MODE_UND: return KVM_SPSR_UND;
 151         case COMPAT_PSR_MODE_IRQ: return KVM_SPSR_IRQ;
 152         case COMPAT_PSR_MODE_FIQ: return KVM_SPSR_FIQ;
 153         default: BUG();
 154         }
 155 }
 156
 157 unsigned long vcpu_read_spsr32(const struct kvm_vcpu *vcpu)
 158 {
 159         int spsr_idx = vcpu_spsr32_mode(vcpu);
 160
 161         if (!vcpu->arch.sysregs_loaded_on_cpu)
 162                 return vcpu_gp_regs(vcpu)->spsr[spsr_idx];
 163
 164         switch (spsr_idx) {
 165         case KVM_SPSR_SVC:
 166                 return read_sysreg_el1(spsr);
 167         case KVM_SPSR_ABT:
 168                 return read_sysreg(spsr_abt);
 169         case KVM_SPSR_UND:
 170                 return read_sysreg(spsr_und);
 171         case KVM_SPSR_IRQ:
 172                 return read_sysreg(spsr_irq);
 173         case KVM_SPSR_FIQ:
 174                 return read_sysreg(spsr_fiq);
 175         default:
 176                 BUG();
 177         }
 178 }
 179
 180 void vcpu_write_spsr32(struct kvm_vcpu *vcpu, unsigned long v)
 181 {
 182         int spsr_idx = vcpu_spsr32_mode(vcpu);
 183
 184         if (!vcpu->arch.sysregs_loaded_on_cpu) {
 185                 vcpu_gp_regs(vcpu)->spsr[spsr_idx] = v;
 186                 return;
 187         }
 188
 189         switch (spsr_idx) {
 190         case KVM_SPSR_SVC:
 191                 write_sysreg_el1(v, spsr);
 192         case KVM_SPSR_ABT:
 193                 write_sysreg(v, spsr_abt);
 194         case KVM_SPSR_UND:
 195                 write_sysreg(v, spsr_und);
 196         case KVM_SPSR_IRQ:
 197                 write_sysreg(v, spsr_irq);
 198         case KVM_SPSR_FIQ:
 199                 write_sysreg(v, spsr_fiq);
 200         }
 201 }