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Diffstat (limited to 'arch/riscv/kvm/vcpu_insn.c')
-rw-r--r--arch/riscv/kvm/vcpu_insn.c175
1 files changed, 51 insertions, 124 deletions
diff --git a/arch/riscv/kvm/vcpu_insn.c b/arch/riscv/kvm/vcpu_insn.c
index 0bb52761a3f7..4d89b94128ae 100644
--- a/arch/riscv/kvm/vcpu_insn.c
+++ b/arch/riscv/kvm/vcpu_insn.c
@@ -7,129 +7,8 @@
#include <linux/bitops.h>
#include <linux/kvm_host.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_CSRRW 0x1073
-#define INSN_MASK_CSRRW 0x707f
-#define INSN_MATCH_CSRRS 0x2073
-#define INSN_MASK_CSRRS 0x707f
-#define INSN_MATCH_CSRRC 0x3073
-#define INSN_MASK_CSRRC 0x707f
-#define INSN_MATCH_CSRRWI 0x5073
-#define INSN_MASK_CSRRWI 0x707f
-#define INSN_MATCH_CSRRSI 0x6073
-#define INSN_MASK_CSRRSI 0x707f
-#define INSN_MATCH_CSRRCI 0x7073
-#define INSN_MASK_CSRRCI 0x707f
-
-#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 MASK_RX 0x1f
-
-#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_FUNCT3(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))
+#include <asm/cpufeature.h>
+#include <asm/insn.h>
struct insn_func {
unsigned long mask;
@@ -201,6 +80,13 @@ static int wfi_insn(struct kvm_vcpu *vcpu, struct kvm_run *run, ulong insn)
return KVM_INSN_CONTINUE_NEXT_SEPC;
}
+static int wrs_insn(struct kvm_vcpu *vcpu, struct kvm_run *run, ulong insn)
+{
+ vcpu->stat.wrs_exit_stat++;
+ kvm_vcpu_on_spin(vcpu, vcpu->arch.guest_context.sstatus & SR_SPP);
+ return KVM_INSN_CONTINUE_NEXT_SEPC;
+}
+
struct csr_func {
unsigned int base;
unsigned int count;
@@ -213,7 +99,21 @@ struct csr_func {
unsigned long wr_mask);
};
-static const struct csr_func csr_funcs[] = { };
+static int seed_csr_rmw(struct kvm_vcpu *vcpu, unsigned int csr_num,
+ unsigned long *val, unsigned long new_val,
+ unsigned long wr_mask)
+{
+ if (!riscv_isa_extension_available(vcpu->arch.isa, ZKR))
+ return KVM_INSN_ILLEGAL_TRAP;
+
+ return KVM_INSN_EXIT_TO_USER_SPACE;
+}
+
+static const struct csr_func csr_funcs[] = {
+ KVM_RISCV_VCPU_AIA_CSR_FUNCS
+ KVM_RISCV_VCPU_HPMCOUNTER_CSR_FUNCS
+ { .base = CSR_SEED, .count = 1, .func = seed_csr_rmw },
+};
/**
* kvm_riscv_vcpu_csr_return -- Handle CSR read/write after user space
@@ -362,6 +262,11 @@ static const struct insn_func system_opcode_funcs[] = {
.match = INSN_MATCH_WFI,
.func = wfi_insn,
},
+ {
+ .mask = INSN_MASK_WRS,
+ .match = INSN_MATCH_WRS,
+ .func = wrs_insn,
+ },
};
static int system_opcode_insn(struct kvm_vcpu *vcpu, struct kvm_run *run,
@@ -393,6 +298,22 @@ static int system_opcode_insn(struct kvm_vcpu *vcpu, struct kvm_run *run,
return (rc <= 0) ? rc : 1;
}
+static bool is_load_guest_page_fault(unsigned long scause)
+{
+ /**
+ * If a g-stage page fault occurs, the direct approach
+ * is to let the g-stage page fault handler handle it
+ * naturally, however, calling the g-stage page fault
+ * handler here seems rather strange.
+ * Considering this is a corner case, we can directly
+ * return to the guest and re-execute the same PC, this
+ * will trigger a g-stage page fault again and then the
+ * regular g-stage page fault handler will populate
+ * g-stage page table.
+ */
+ return (scause == EXC_LOAD_GUEST_PAGE_FAULT);
+}
+
/**
* kvm_riscv_vcpu_virtual_insn -- Handle virtual instruction trap
*
@@ -418,6 +339,8 @@ int kvm_riscv_vcpu_virtual_insn(struct kvm_vcpu *vcpu, struct kvm_run *run,
ct->sepc,
&utrap);
if (utrap.scause) {
+ if (is_load_guest_page_fault(utrap.scause))
+ return 1;
utrap.sepc = ct->sepc;
kvm_riscv_vcpu_trap_redirect(vcpu, &utrap);
return 1;
@@ -473,6 +396,8 @@ int kvm_riscv_vcpu_mmio_load(struct kvm_vcpu *vcpu, struct kvm_run *run,
insn = kvm_riscv_vcpu_unpriv_read(vcpu, true, ct->sepc,
&utrap);
if (utrap.scause) {
+ if (is_load_guest_page_fault(utrap.scause))
+ return 1;
/* Redirect trap if we failed to read instruction */
utrap.sepc = ct->sepc;
kvm_riscv_vcpu_trap_redirect(vcpu, &utrap);
@@ -599,6 +524,8 @@ int kvm_riscv_vcpu_mmio_store(struct kvm_vcpu *vcpu, struct kvm_run *run,
insn = kvm_riscv_vcpu_unpriv_read(vcpu, true, ct->sepc,
&utrap);
if (utrap.scause) {
+ if (is_load_guest_page_fault(utrap.scause))
+ return 1;
/* Redirect trap if we failed to read instruction */
utrap.sepc = ct->sepc;
kvm_riscv_vcpu_trap_redirect(vcpu, &utrap);
generated by cgit (git 2.34.1) at 2025-12-25 10:10:23 +0000