diff options
Diffstat (limited to '')
| -rw-r--r-- | arch/riscv/kvm/vcpu_exit.c | 531 |
1 files changed, 21 insertions, 510 deletions
diff --git a/arch/riscv/kvm/vcpu_exit.c b/arch/riscv/kvm/vcpu_exit.c index 7f2d742ae4c6..c9f741ab26f5 100644 --- a/arch/riscv/kvm/vcpu_exit.c +++ b/arch/riscv/kvm/vcpu_exit.c @@ -6,446 +6,41 @@ * Anup Patel <anup.patel@wdc.com> */ -#include <linux/bitops.h> -#include <linux/errno.h> -#include <linux/err.h> #include <linux/kvm_host.h> #include <asm/csr.h> +#include <asm/insn-def.h> -#define INSN_OPCODE_MASK 0x007c -#define INSN_OPCODE_SHIFT 2 -#define INSN_OPCODE_SYSTEM 28 - -#define INSN_MASK_WFI 0xffffffff -#define INSN_MATCH_WFI 0x10500073 - -#define INSN_MATCH_LB 0x3 -#define INSN_MASK_LB 0x707f -#define INSN_MATCH_LH 0x1003 -#define INSN_MASK_LH 0x707f -#define INSN_MATCH_LW 0x2003 -#define INSN_MASK_LW 0x707f -#define INSN_MATCH_LD 0x3003 -#define INSN_MASK_LD 0x707f -#define INSN_MATCH_LBU 0x4003 -#define INSN_MASK_LBU 0x707f -#define INSN_MATCH_LHU 0x5003 -#define INSN_MASK_LHU 0x707f -#define INSN_MATCH_LWU 0x6003 -#define INSN_MASK_LWU 0x707f -#define INSN_MATCH_SB 0x23 -#define INSN_MASK_SB 0x707f -#define INSN_MATCH_SH 0x1023 -#define INSN_MASK_SH 0x707f -#define INSN_MATCH_SW 0x2023 -#define INSN_MASK_SW 0x707f -#define INSN_MATCH_SD 0x3023 -#define INSN_MASK_SD 0x707f - -#define INSN_MATCH_C_LD 0x6000 -#define INSN_MASK_C_LD 0xe003 -#define INSN_MATCH_C_SD 0xe000 -#define INSN_MASK_C_SD 0xe003 -#define INSN_MATCH_C_LW 0x4000 -#define INSN_MASK_C_LW 0xe003 -#define INSN_MATCH_C_SW 0xc000 -#define INSN_MASK_C_SW 0xe003 -#define INSN_MATCH_C_LDSP 0x6002 -#define INSN_MASK_C_LDSP 0xe003 -#define INSN_MATCH_C_SDSP 0xe002 -#define INSN_MASK_C_SDSP 0xe003 -#define INSN_MATCH_C_LWSP 0x4002 -#define INSN_MASK_C_LWSP 0xe003 -#define INSN_MATCH_C_SWSP 0xc002 -#define INSN_MASK_C_SWSP 0xe003 - -#define INSN_16BIT_MASK 0x3 - -#define INSN_IS_16BIT(insn) (((insn) & INSN_16BIT_MASK) != INSN_16BIT_MASK) - -#define INSN_LEN(insn) (INSN_IS_16BIT(insn) ? 2 : 4) - -#ifdef CONFIG_64BIT -#define LOG_REGBYTES 3 -#else -#define LOG_REGBYTES 2 -#endif -#define REGBYTES (1 << LOG_REGBYTES) - -#define SH_RD 7 -#define SH_RS1 15 -#define SH_RS2 20 -#define SH_RS2C 2 - -#define RV_X(x, s, n) (((x) >> (s)) & ((1 << (n)) - 1)) -#define RVC_LW_IMM(x) ((RV_X(x, 6, 1) << 2) | \ - (RV_X(x, 10, 3) << 3) | \ - (RV_X(x, 5, 1) << 6)) -#define RVC_LD_IMM(x) ((RV_X(x, 10, 3) << 3) | \ - (RV_X(x, 5, 2) << 6)) -#define RVC_LWSP_IMM(x) ((RV_X(x, 4, 3) << 2) | \ - (RV_X(x, 12, 1) << 5) | \ - (RV_X(x, 2, 2) << 6)) -#define RVC_LDSP_IMM(x) ((RV_X(x, 5, 2) << 3) | \ - (RV_X(x, 12, 1) << 5) | \ - (RV_X(x, 2, 3) << 6)) -#define RVC_SWSP_IMM(x) ((RV_X(x, 9, 4) << 2) | \ - (RV_X(x, 7, 2) << 6)) -#define RVC_SDSP_IMM(x) ((RV_X(x, 10, 3) << 3) | \ - (RV_X(x, 7, 3) << 6)) -#define RVC_RS1S(insn) (8 + RV_X(insn, SH_RD, 3)) -#define RVC_RS2S(insn) (8 + RV_X(insn, SH_RS2C, 3)) -#define RVC_RS2(insn) RV_X(insn, SH_RS2C, 5) - -#define SHIFT_RIGHT(x, y) \ - ((y) < 0 ? ((x) << -(y)) : ((x) >> (y))) - -#define REG_MASK \ - ((1 << (5 + LOG_REGBYTES)) - (1 << LOG_REGBYTES)) - -#define REG_OFFSET(insn, pos) \ - (SHIFT_RIGHT((insn), (pos) - LOG_REGBYTES) & REG_MASK) - -#define REG_PTR(insn, pos, regs) \ - ((ulong *)((ulong)(regs) + REG_OFFSET(insn, pos))) - -#define GET_RM(insn) (((insn) >> 12) & 7) - -#define GET_RS1(insn, regs) (*REG_PTR(insn, SH_RS1, regs)) -#define GET_RS2(insn, regs) (*REG_PTR(insn, SH_RS2, regs)) -#define GET_RS1S(insn, regs) (*REG_PTR(RVC_RS1S(insn), 0, regs)) -#define GET_RS2S(insn, regs) (*REG_PTR(RVC_RS2S(insn), 0, regs)) -#define GET_RS2C(insn, regs) (*REG_PTR(insn, SH_RS2C, regs)) -#define GET_SP(regs) (*REG_PTR(2, 0, regs)) -#define SET_RD(insn, regs, val) (*REG_PTR(insn, SH_RD, regs) = (val)) -#define IMM_I(insn) ((s32)(insn) >> 20) -#define IMM_S(insn) (((s32)(insn) >> 25 << 5) | \ - (s32)(((insn) >> 7) & 0x1f)) -#define MASK_FUNCT3 0x7000 - -static int truly_illegal_insn(struct kvm_vcpu *vcpu, - struct kvm_run *run, - ulong insn) -{ - struct kvm_cpu_trap utrap = { 0 }; - - /* Redirect trap to Guest VCPU */ - utrap.sepc = vcpu->arch.guest_context.sepc; - utrap.scause = EXC_INST_ILLEGAL; - utrap.stval = insn; - kvm_riscv_vcpu_trap_redirect(vcpu, &utrap); - - return 1; -} - -static int system_opcode_insn(struct kvm_vcpu *vcpu, - struct kvm_run *run, - ulong insn) -{ - if ((insn & INSN_MASK_WFI) == INSN_MATCH_WFI) { - vcpu->stat.wfi_exit_stat++; - if (!kvm_arch_vcpu_runnable(vcpu)) { - srcu_read_unlock(&vcpu->kvm->srcu, vcpu->arch.srcu_idx); - kvm_vcpu_block(vcpu); - vcpu->arch.srcu_idx = srcu_read_lock(&vcpu->kvm->srcu); - kvm_clear_request(KVM_REQ_UNHALT, vcpu); - } - vcpu->arch.guest_context.sepc += INSN_LEN(insn); - return 1; - } - - return truly_illegal_insn(vcpu, run, insn); -} - -static int virtual_inst_fault(struct kvm_vcpu *vcpu, struct kvm_run *run, - struct kvm_cpu_trap *trap) -{ - unsigned long insn = trap->stval; - struct kvm_cpu_trap utrap = { 0 }; - struct kvm_cpu_context *ct; - - if (unlikely(INSN_IS_16BIT(insn))) { - if (insn == 0) { - ct = &vcpu->arch.guest_context; - insn = kvm_riscv_vcpu_unpriv_read(vcpu, true, - ct->sepc, - &utrap); - if (utrap.scause) { - utrap.sepc = ct->sepc; - kvm_riscv_vcpu_trap_redirect(vcpu, &utrap); - return 1; - } - } - if (INSN_IS_16BIT(insn)) - return truly_illegal_insn(vcpu, run, insn); - } - - switch ((insn & INSN_OPCODE_MASK) >> INSN_OPCODE_SHIFT) { - case INSN_OPCODE_SYSTEM: - return system_opcode_insn(vcpu, run, insn); - default: - return truly_illegal_insn(vcpu, run, insn); - } -} - -static int emulate_load(struct kvm_vcpu *vcpu, struct kvm_run *run, - unsigned long fault_addr, unsigned long htinst) -{ - u8 data_buf[8]; - unsigned long insn; - int shift = 0, len = 0, insn_len = 0; - struct kvm_cpu_trap utrap = { 0 }; - struct kvm_cpu_context *ct = &vcpu->arch.guest_context; - - /* Determine trapped instruction */ - if (htinst & 0x1) { - /* - * Bit[0] == 1 implies trapped instruction value is - * transformed instruction or custom instruction. - */ - insn = htinst | INSN_16BIT_MASK; - insn_len = (htinst & BIT(1)) ? INSN_LEN(insn) : 2; - } else { - /* - * Bit[0] == 0 implies trapped instruction value is - * zero or special value. - */ - insn = kvm_riscv_vcpu_unpriv_read(vcpu, true, ct->sepc, - &utrap); - if (utrap.scause) { - /* Redirect trap if we failed to read instruction */ - utrap.sepc = ct->sepc; - kvm_riscv_vcpu_trap_redirect(vcpu, &utrap); - return 1; - } - insn_len = INSN_LEN(insn); - } - - /* Decode length of MMIO and shift */ - if ((insn & INSN_MASK_LW) == INSN_MATCH_LW) { - len = 4; - shift = 8 * (sizeof(ulong) - len); - } else if ((insn & INSN_MASK_LB) == INSN_MATCH_LB) { - len = 1; - shift = 8 * (sizeof(ulong) - len); - } else if ((insn & INSN_MASK_LBU) == INSN_MATCH_LBU) { - len = 1; - shift = 8 * (sizeof(ulong) - len); -#ifdef CONFIG_64BIT - } else if ((insn & INSN_MASK_LD) == INSN_MATCH_LD) { - len = 8; - shift = 8 * (sizeof(ulong) - len); - } else if ((insn & INSN_MASK_LWU) == INSN_MATCH_LWU) { - len = 4; -#endif - } else if ((insn & INSN_MASK_LH) == INSN_MATCH_LH) { - len = 2; - shift = 8 * (sizeof(ulong) - len); - } else if ((insn & INSN_MASK_LHU) == INSN_MATCH_LHU) { - len = 2; -#ifdef CONFIG_64BIT - } else if ((insn & INSN_MASK_C_LD) == INSN_MATCH_C_LD) { - len = 8; - shift = 8 * (sizeof(ulong) - len); - insn = RVC_RS2S(insn) << SH_RD; - } else if ((insn & INSN_MASK_C_LDSP) == INSN_MATCH_C_LDSP && - ((insn >> SH_RD) & 0x1f)) { - len = 8; - shift = 8 * (sizeof(ulong) - len); -#endif - } else if ((insn & INSN_MASK_C_LW) == INSN_MATCH_C_LW) { - len = 4; - shift = 8 * (sizeof(ulong) - len); - insn = RVC_RS2S(insn) << SH_RD; - } else if ((insn & INSN_MASK_C_LWSP) == INSN_MATCH_C_LWSP && - ((insn >> SH_RD) & 0x1f)) { - len = 4; - shift = 8 * (sizeof(ulong) - len); - } else { - return -EOPNOTSUPP; - } - - /* Fault address should be aligned to length of MMIO */ - if (fault_addr & (len - 1)) - return -EIO; - - /* Save instruction decode info */ - vcpu->arch.mmio_decode.insn = insn; - vcpu->arch.mmio_decode.insn_len = insn_len; - vcpu->arch.mmio_decode.shift = shift; - vcpu->arch.mmio_decode.len = len; - vcpu->arch.mmio_decode.return_handled = 0; - - /* Update MMIO details in kvm_run struct */ - run->mmio.is_write = false; - run->mmio.phys_addr = fault_addr; - run->mmio.len = len; - - /* Try to handle MMIO access in the kernel */ - if (!kvm_io_bus_read(vcpu, KVM_MMIO_BUS, fault_addr, len, data_buf)) { - /* Successfully handled MMIO access in the kernel so resume */ - memcpy(run->mmio.data, data_buf, len); - vcpu->stat.mmio_exit_kernel++; - kvm_riscv_vcpu_mmio_return(vcpu, run); - return 1; - } - - /* Exit to userspace for MMIO emulation */ - vcpu->stat.mmio_exit_user++; - run->exit_reason = KVM_EXIT_MMIO; - - return 0; -} - -static int emulate_store(struct kvm_vcpu *vcpu, struct kvm_run *run, - unsigned long fault_addr, unsigned long htinst) -{ - u8 data8; - u16 data16; - u32 data32; - u64 data64; - ulong data; - unsigned long insn; - int len = 0, insn_len = 0; - struct kvm_cpu_trap utrap = { 0 }; - struct kvm_cpu_context *ct = &vcpu->arch.guest_context; - - /* Determine trapped instruction */ - if (htinst & 0x1) { - /* - * Bit[0] == 1 implies trapped instruction value is - * transformed instruction or custom instruction. - */ - insn = htinst | INSN_16BIT_MASK; - insn_len = (htinst & BIT(1)) ? INSN_LEN(insn) : 2; - } else { - /* - * Bit[0] == 0 implies trapped instruction value is - * zero or special value. - */ - insn = kvm_riscv_vcpu_unpriv_read(vcpu, true, ct->sepc, - &utrap); - if (utrap.scause) { - /* Redirect trap if we failed to read instruction */ - utrap.sepc = ct->sepc; - kvm_riscv_vcpu_trap_redirect(vcpu, &utrap); - return 1; - } - insn_len = INSN_LEN(insn); - } - - data = GET_RS2(insn, &vcpu->arch.guest_context); - data8 = data16 = data32 = data64 = data; - - if ((insn & INSN_MASK_SW) == INSN_MATCH_SW) { - len = 4; - } else if ((insn & INSN_MASK_SB) == INSN_MATCH_SB) { - len = 1; -#ifdef CONFIG_64BIT - } else if ((insn & INSN_MASK_SD) == INSN_MATCH_SD) { - len = 8; -#endif - } else if ((insn & INSN_MASK_SH) == INSN_MATCH_SH) { - len = 2; -#ifdef CONFIG_64BIT - } else if ((insn & INSN_MASK_C_SD) == INSN_MATCH_C_SD) { - len = 8; - data64 = GET_RS2S(insn, &vcpu->arch.guest_context); - } else if ((insn & INSN_MASK_C_SDSP) == INSN_MATCH_C_SDSP && - ((insn >> SH_RD) & 0x1f)) { - len = 8; - data64 = GET_RS2C(insn, &vcpu->arch.guest_context); -#endif - } else if ((insn & INSN_MASK_C_SW) == INSN_MATCH_C_SW) { - len = 4; - data32 = GET_RS2S(insn, &vcpu->arch.guest_context); - } else if ((insn & INSN_MASK_C_SWSP) == INSN_MATCH_C_SWSP && - ((insn >> SH_RD) & 0x1f)) { - len = 4; - data32 = GET_RS2C(insn, &vcpu->arch.guest_context); - } else { - return -EOPNOTSUPP; - } - - /* Fault address should be aligned to length of MMIO */ - if (fault_addr & (len - 1)) - return -EIO; - - /* Save instruction decode info */ - vcpu->arch.mmio_decode.insn = insn; - vcpu->arch.mmio_decode.insn_len = insn_len; - vcpu->arch.mmio_decode.shift = 0; - vcpu->arch.mmio_decode.len = len; - vcpu->arch.mmio_decode.return_handled = 0; - - /* Copy data to kvm_run instance */ - switch (len) { - case 1: - *((u8 *)run->mmio.data) = data8; - break; - case 2: - *((u16 *)run->mmio.data) = data16; - break; - case 4: - *((u32 *)run->mmio.data) = data32; - break; - case 8: - *((u64 *)run->mmio.data) = data64; - break; - default: - return -EOPNOTSUPP; - } - - /* Update MMIO details in kvm_run struct */ - run->mmio.is_write = true; - run->mmio.phys_addr = fault_addr; - run->mmio.len = len; - - /* Try to handle MMIO access in the kernel */ - if (!kvm_io_bus_write(vcpu, KVM_MMIO_BUS, - fault_addr, len, run->mmio.data)) { - /* Successfully handled MMIO access in the kernel so resume */ - vcpu->stat.mmio_exit_kernel++; - kvm_riscv_vcpu_mmio_return(vcpu, run); - return 1; - } - - /* Exit to userspace for MMIO emulation */ - vcpu->stat.mmio_exit_user++; - run->exit_reason = KVM_EXIT_MMIO; - - return 0; -} - -static int stage2_page_fault(struct kvm_vcpu *vcpu, struct kvm_run *run, +static int gstage_page_fault(struct kvm_vcpu *vcpu, struct kvm_run *run, struct kvm_cpu_trap *trap) { struct kvm_memory_slot *memslot; unsigned long hva, fault_addr; - bool writeable; + bool writable; gfn_t gfn; int ret; fault_addr = (trap->htval << 2) | (trap->stval & 0x3); gfn = fault_addr >> PAGE_SHIFT; memslot = gfn_to_memslot(vcpu->kvm, gfn); - hva = gfn_to_hva_memslot_prot(memslot, gfn, &writeable); + hva = gfn_to_hva_memslot_prot(memslot, gfn, &writable); if (kvm_is_error_hva(hva) || - (trap->scause == EXC_STORE_GUEST_PAGE_FAULT && !writeable)) { + (trap->scause == EXC_STORE_GUEST_PAGE_FAULT && !writable)) { switch (trap->scause) { case EXC_LOAD_GUEST_PAGE_FAULT: - return emulate_load(vcpu, run, fault_addr, - trap->htinst); + return kvm_riscv_vcpu_mmio_load(vcpu, run, + fault_addr, + trap->htinst); case EXC_STORE_GUEST_PAGE_FAULT: - return emulate_store(vcpu, run, fault_addr, - trap->htinst); + return kvm_riscv_vcpu_mmio_store(vcpu, run, + fault_addr, + trap->htinst); default: return -EOPNOTSUPP; }; } - ret = kvm_riscv_stage2_map(vcpu, memslot, fault_addr, hva, + ret = kvm_riscv_gstage_map(vcpu, memslot, fault_addr, hva, (trap->scause == EXC_STORE_GUEST_PAGE_FAULT) ? true : false); if (ret < 0) return ret; @@ -468,11 +63,7 @@ unsigned long kvm_riscv_vcpu_unpriv_read(struct kvm_vcpu *vcpu, { register unsigned long taddr asm("a0") = (unsigned long)trap; register unsigned long ttmp asm("a1"); - register unsigned long val asm("t0"); - register unsigned long tmp asm("t1"); - register unsigned long addr asm("t2") = guest_addr; - unsigned long flags; - unsigned long old_stvec, old_hstatus; + unsigned long flags, val, tmp, old_stvec, old_hstatus; local_irq_save(flags); @@ -488,29 +79,19 @@ unsigned long kvm_riscv_vcpu_unpriv_read(struct kvm_vcpu *vcpu, ".option push\n" ".option norvc\n" "add %[ttmp], %[taddr], 0\n" - /* - * HLVX.HU %[val], (%[addr]) - * HLVX.HU t0, (t2) - * 0110010 00011 00111 100 00101 1110011 - */ - ".word 0x6433c2f3\n" + HLVX_HU(%[val], %[addr]) "andi %[tmp], %[val], 3\n" "addi %[tmp], %[tmp], -3\n" "bne %[tmp], zero, 2f\n" "addi %[addr], %[addr], 2\n" - /* - * HLVX.HU %[tmp], (%[addr]) - * HLVX.HU t1, (t2) - * 0110010 00011 00111 100 00110 1110011 - */ - ".word 0x6433c373\n" + HLVX_HU(%[tmp], %[addr]) "sll %[tmp], %[tmp], 16\n" "add %[val], %[val], %[tmp]\n" "2:\n" ".option pop" : [val] "=&r" (val), [tmp] "=&r" (tmp), [taddr] "+&r" (taddr), [ttmp] "+&r" (ttmp), - [addr] "+&r" (addr) : : "memory"); + [addr] "+&r" (guest_addr) : : "memory"); if (trap->scause == EXC_LOAD_PAGE_FAULT) trap->scause = EXC_INST_PAGE_FAULT; @@ -527,24 +108,14 @@ unsigned long kvm_riscv_vcpu_unpriv_read(struct kvm_vcpu *vcpu, ".option norvc\n" "add %[ttmp], %[taddr], 0\n" #ifdef CONFIG_64BIT - /* - * HLV.D %[val], (%[addr]) - * HLV.D t0, (t2) - * 0110110 00000 00111 100 00101 1110011 - */ - ".word 0x6c03c2f3\n" + HLV_D(%[val], %[addr]) #else - /* - * HLV.W %[val], (%[addr]) - * HLV.W t0, (t2) - * 0110100 00000 00111 100 00101 1110011 - */ - ".word 0x6803c2f3\n" + HLV_W(%[val], %[addr]) #endif ".option pop" : [val] "=&r" (val), [taddr] "+&r" (taddr), [ttmp] "+&r" (ttmp) - : [addr] "r" (addr) : "memory"); + : [addr] "r" (guest_addr) : "memory"); } csr_write(CSR_STVEC, old_stvec); @@ -591,66 +162,6 @@ void kvm_riscv_vcpu_trap_redirect(struct kvm_vcpu *vcpu, vcpu->arch.guest_context.sepc = csr_read(CSR_VSTVEC); } -/** - * kvm_riscv_vcpu_mmio_return -- Handle MMIO loads after user space emulation - * or in-kernel IO emulation - * - * @vcpu: The VCPU pointer - * @run: The VCPU run struct containing the mmio data - */ -int kvm_riscv_vcpu_mmio_return(struct kvm_vcpu *vcpu, struct kvm_run *run) -{ - u8 data8; - u16 data16; - u32 data32; - u64 data64; - ulong insn; - int len, shift; - - if (vcpu->arch.mmio_decode.return_handled) - return 0; - - vcpu->arch.mmio_decode.return_handled = 1; - insn = vcpu->arch.mmio_decode.insn; - - if (run->mmio.is_write) - goto done; - - len = vcpu->arch.mmio_decode.len; - shift = vcpu->arch.mmio_decode.shift; - - switch (len) { - case 1: - data8 = *((u8 *)run->mmio.data); - SET_RD(insn, &vcpu->arch.guest_context, - (ulong)data8 << shift >> shift); - break; - case 2: - data16 = *((u16 *)run->mmio.data); - SET_RD(insn, &vcpu->arch.guest_context, - (ulong)data16 << shift >> shift); - break; - case 4: - data32 = *((u32 *)run->mmio.data); - SET_RD(insn, &vcpu->arch.guest_context, - (ulong)data32 << shift >> shift); - break; - case 8: - data64 = *((u64 *)run->mmio.data); - SET_RD(insn, &vcpu->arch.guest_context, - (ulong)data64 << shift >> shift); - break; - default: - return -EOPNOTSUPP; - } - -done: - /* Move to next instruction */ - vcpu->arch.guest_context.sepc += vcpu->arch.mmio_decode.insn_len; - - return 0; -} - /* * Return > 0 to return to guest, < 0 on error, 0 (and set exit_reason) on * proper exit to userspace. @@ -670,13 +181,13 @@ int kvm_riscv_vcpu_exit(struct kvm_vcpu *vcpu, struct kvm_run *run, switch (trap->scause) { case EXC_VIRTUAL_INST_FAULT: if (vcpu->arch.guest_context.hstatus & HSTATUS_SPV) - ret = virtual_inst_fault(vcpu, run, trap); + ret = kvm_riscv_vcpu_virtual_insn(vcpu, run, trap); break; case EXC_INST_GUEST_PAGE_FAULT: case EXC_LOAD_GUEST_PAGE_FAULT: case EXC_STORE_GUEST_PAGE_FAULT: if (vcpu->arch.guest_context.hstatus & HSTATUS_SPV) - ret = stage2_page_fault(vcpu, run, trap); + ret = gstage_page_fault(vcpu, run, trap); break; case EXC_SUPERVISOR_SYSCALL: if (vcpu->arch.guest_context.hstatus & HSTATUS_SPV) |