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-rw-r--r--arch/arm64/kvm/at.c1446
1 files changed, 1446 insertions, 0 deletions
diff --git a/arch/arm64/kvm/at.c b/arch/arm64/kvm/at.c
new file mode 100644
index 000000000000..f74a66ce3064
--- /dev/null
+++ b/arch/arm64/kvm/at.c
@@ -0,0 +1,1446 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2017 - Linaro Ltd
+ * Author: Jintack Lim <jintack.lim@linaro.org>
+ */
+
+#include <linux/kvm_host.h>
+
+#include <asm/esr.h>
+#include <asm/kvm_hyp.h>
+#include <asm/kvm_mmu.h>
+
+enum trans_regime {
+ TR_EL10,
+ TR_EL20,
+ TR_EL2,
+};
+
+struct s1_walk_info {
+ u64 baddr;
+ enum trans_regime regime;
+ unsigned int max_oa_bits;
+ unsigned int pgshift;
+ unsigned int txsz;
+ int sl;
+ bool hpd;
+ bool e0poe;
+ bool poe;
+ bool pan;
+ bool be;
+ bool s2;
+};
+
+struct s1_walk_result {
+ union {
+ struct {
+ u64 desc;
+ u64 pa;
+ s8 level;
+ u8 APTable;
+ bool UXNTable;
+ bool PXNTable;
+ bool uwxn;
+ bool uov;
+ bool ur;
+ bool uw;
+ bool ux;
+ bool pwxn;
+ bool pov;
+ bool pr;
+ bool pw;
+ bool px;
+ };
+ struct {
+ u8 fst;
+ bool ptw;
+ bool s2;
+ };
+ };
+ bool failed;
+};
+
+static void fail_s1_walk(struct s1_walk_result *wr, u8 fst, bool ptw, bool s2)
+{
+ wr->fst = fst;
+ wr->ptw = ptw;
+ wr->s2 = s2;
+ wr->failed = true;
+}
+
+#define S1_MMU_DISABLED (-127)
+
+static int get_ia_size(struct s1_walk_info *wi)
+{
+ return 64 - wi->txsz;
+}
+
+/* Return true if the IPA is out of the OA range */
+static bool check_output_size(u64 ipa, struct s1_walk_info *wi)
+{
+ return wi->max_oa_bits < 48 && (ipa & GENMASK_ULL(47, wi->max_oa_bits));
+}
+
+/* Return the translation regime that applies to an AT instruction */
+static enum trans_regime compute_translation_regime(struct kvm_vcpu *vcpu, u32 op)
+{
+ /*
+ * We only get here from guest EL2, so the translation
+ * regime AT applies to is solely defined by {E2H,TGE}.
+ */
+ switch (op) {
+ case OP_AT_S1E2R:
+ case OP_AT_S1E2W:
+ case OP_AT_S1E2A:
+ return vcpu_el2_e2h_is_set(vcpu) ? TR_EL20 : TR_EL2;
+ break;
+ default:
+ return (vcpu_el2_e2h_is_set(vcpu) &&
+ vcpu_el2_tge_is_set(vcpu)) ? TR_EL20 : TR_EL10;
+ }
+}
+
+static bool s1pie_enabled(struct kvm_vcpu *vcpu, enum trans_regime regime)
+{
+ if (!kvm_has_s1pie(vcpu->kvm))
+ return false;
+
+ switch (regime) {
+ case TR_EL2:
+ case TR_EL20:
+ return vcpu_read_sys_reg(vcpu, TCR2_EL2) & TCR2_EL2_PIE;
+ case TR_EL10:
+ return (__vcpu_sys_reg(vcpu, HCRX_EL2) & HCRX_EL2_TCR2En) &&
+ (__vcpu_sys_reg(vcpu, TCR2_EL1) & TCR2_EL1_PIE);
+ default:
+ BUG();
+ }
+}
+
+static void compute_s1poe(struct kvm_vcpu *vcpu, struct s1_walk_info *wi)
+{
+ u64 val;
+
+ if (!kvm_has_s1poe(vcpu->kvm)) {
+ wi->poe = wi->e0poe = false;
+ return;
+ }
+
+ switch (wi->regime) {
+ case TR_EL2:
+ case TR_EL20:
+ val = vcpu_read_sys_reg(vcpu, TCR2_EL2);
+ wi->poe = val & TCR2_EL2_POE;
+ wi->e0poe = (wi->regime == TR_EL20) && (val & TCR2_EL2_E0POE);
+ break;
+ case TR_EL10:
+ if (__vcpu_sys_reg(vcpu, HCRX_EL2) & HCRX_EL2_TCR2En) {
+ wi->poe = wi->e0poe = false;
+ return;
+ }
+
+ val = __vcpu_sys_reg(vcpu, TCR2_EL1);
+ wi->poe = val & TCR2_EL1_POE;
+ wi->e0poe = val & TCR2_EL1_E0POE;
+ }
+}
+
+static int setup_s1_walk(struct kvm_vcpu *vcpu, u32 op, struct s1_walk_info *wi,
+ struct s1_walk_result *wr, u64 va)
+{
+ u64 hcr, sctlr, tcr, tg, ps, ia_bits, ttbr;
+ unsigned int stride, x;
+ bool va55, tbi, lva, as_el0;
+
+ hcr = __vcpu_sys_reg(vcpu, HCR_EL2);
+
+ wi->regime = compute_translation_regime(vcpu, op);
+ as_el0 = (op == OP_AT_S1E0R || op == OP_AT_S1E0W);
+ wi->pan = (op == OP_AT_S1E1RP || op == OP_AT_S1E1WP) &&
+ (*vcpu_cpsr(vcpu) & PSR_PAN_BIT);
+
+ va55 = va & BIT(55);
+
+ if (wi->regime == TR_EL2 && va55)
+ goto addrsz;
+
+ wi->s2 = wi->regime == TR_EL10 && (hcr & (HCR_VM | HCR_DC));
+
+ switch (wi->regime) {
+ case TR_EL10:
+ sctlr = vcpu_read_sys_reg(vcpu, SCTLR_EL1);
+ tcr = vcpu_read_sys_reg(vcpu, TCR_EL1);
+ ttbr = (va55 ?
+ vcpu_read_sys_reg(vcpu, TTBR1_EL1) :
+ vcpu_read_sys_reg(vcpu, TTBR0_EL1));
+ break;
+ case TR_EL2:
+ case TR_EL20:
+ sctlr = vcpu_read_sys_reg(vcpu, SCTLR_EL2);
+ tcr = vcpu_read_sys_reg(vcpu, TCR_EL2);
+ ttbr = (va55 ?
+ vcpu_read_sys_reg(vcpu, TTBR1_EL2) :
+ vcpu_read_sys_reg(vcpu, TTBR0_EL2));
+ break;
+ default:
+ BUG();
+ }
+
+ tbi = (wi->regime == TR_EL2 ?
+ FIELD_GET(TCR_EL2_TBI, tcr) :
+ (va55 ?
+ FIELD_GET(TCR_TBI1, tcr) :
+ FIELD_GET(TCR_TBI0, tcr)));
+
+ if (!tbi && (u64)sign_extend64(va, 55) != va)
+ goto addrsz;
+
+ va = (u64)sign_extend64(va, 55);
+
+ /* Let's put the MMU disabled case aside immediately */
+ switch (wi->regime) {
+ case TR_EL10:
+ /*
+ * If dealing with the EL1&0 translation regime, 3 things
+ * can disable the S1 translation:
+ *
+ * - HCR_EL2.DC = 1
+ * - HCR_EL2.{E2H,TGE} = {0,1}
+ * - SCTLR_EL1.M = 0
+ *
+ * The TGE part is interesting. If we have decided that this
+ * is EL1&0, then it means that either {E2H,TGE} == {1,0} or
+ * {0,x}, and we only need to test for TGE == 1.
+ */
+ if (hcr & (HCR_DC | HCR_TGE)) {
+ wr->level = S1_MMU_DISABLED;
+ break;
+ }
+ fallthrough;
+ case TR_EL2:
+ case TR_EL20:
+ if (!(sctlr & SCTLR_ELx_M))
+ wr->level = S1_MMU_DISABLED;
+ break;
+ }
+
+ if (wr->level == S1_MMU_DISABLED) {
+ if (va >= BIT(kvm_get_pa_bits(vcpu->kvm)))
+ goto addrsz;
+
+ wr->pa = va;
+ return 0;
+ }
+
+ wi->be = sctlr & SCTLR_ELx_EE;
+
+ wi->hpd = kvm_has_feat(vcpu->kvm, ID_AA64MMFR1_EL1, HPDS, IMP);
+ wi->hpd &= (wi->regime == TR_EL2 ?
+ FIELD_GET(TCR_EL2_HPD, tcr) :
+ (va55 ?
+ FIELD_GET(TCR_HPD1, tcr) :
+ FIELD_GET(TCR_HPD0, tcr)));
+ /* R_JHSVW */
+ wi->hpd |= s1pie_enabled(vcpu, wi->regime);
+
+ /* Do we have POE? */
+ compute_s1poe(vcpu, wi);
+
+ /* R_BVXDG */
+ wi->hpd |= (wi->poe || wi->e0poe);
+
+ /* Someone was silly enough to encode TG0/TG1 differently */
+ if (va55) {
+ wi->txsz = FIELD_GET(TCR_T1SZ_MASK, tcr);
+ tg = FIELD_GET(TCR_TG1_MASK, tcr);
+
+ switch (tg << TCR_TG1_SHIFT) {
+ case TCR_TG1_4K:
+ wi->pgshift = 12; break;
+ case TCR_TG1_16K:
+ wi->pgshift = 14; break;
+ case TCR_TG1_64K:
+ default: /* IMPDEF: treat any other value as 64k */
+ wi->pgshift = 16; break;
+ }
+ } else {
+ wi->txsz = FIELD_GET(TCR_T0SZ_MASK, tcr);
+ tg = FIELD_GET(TCR_TG0_MASK, tcr);
+
+ switch (tg << TCR_TG0_SHIFT) {
+ case TCR_TG0_4K:
+ wi->pgshift = 12; break;
+ case TCR_TG0_16K:
+ wi->pgshift = 14; break;
+ case TCR_TG0_64K:
+ default: /* IMPDEF: treat any other value as 64k */
+ wi->pgshift = 16; break;
+ }
+ }
+
+ /* R_PLCGL, R_YXNYW */
+ if (!kvm_has_feat_enum(vcpu->kvm, ID_AA64MMFR2_EL1, ST, 48_47)) {
+ if (wi->txsz > 39)
+ goto transfault_l0;
+ } else {
+ if (wi->txsz > 48 || (BIT(wi->pgshift) == SZ_64K && wi->txsz > 47))
+ goto transfault_l0;
+ }
+
+ /* R_GTJBY, R_SXWGM */
+ switch (BIT(wi->pgshift)) {
+ case SZ_4K:
+ lva = kvm_has_feat(vcpu->kvm, ID_AA64MMFR0_EL1, TGRAN4, 52_BIT);
+ lva &= tcr & (wi->regime == TR_EL2 ? TCR_EL2_DS : TCR_DS);
+ break;
+ case SZ_16K:
+ lva = kvm_has_feat(vcpu->kvm, ID_AA64MMFR0_EL1, TGRAN16, 52_BIT);
+ lva &= tcr & (wi->regime == TR_EL2 ? TCR_EL2_DS : TCR_DS);
+ break;
+ case SZ_64K:
+ lva = kvm_has_feat(vcpu->kvm, ID_AA64MMFR2_EL1, VARange, 52);
+ break;
+ }
+
+ if ((lva && wi->txsz < 12) || (!lva && wi->txsz < 16))
+ goto transfault_l0;
+
+ ia_bits = get_ia_size(wi);
+
+ /* R_YYVYV, I_THCZK */
+ if ((!va55 && va > GENMASK(ia_bits - 1, 0)) ||
+ (va55 && va < GENMASK(63, ia_bits)))
+ goto transfault_l0;
+
+ /* I_ZFSYQ */
+ if (wi->regime != TR_EL2 &&
+ (tcr & (va55 ? TCR_EPD1_MASK : TCR_EPD0_MASK)))
+ goto transfault_l0;
+
+ /* R_BNDVG and following statements */
+ if (kvm_has_feat(vcpu->kvm, ID_AA64MMFR2_EL1, E0PD, IMP) &&
+ as_el0 && (tcr & (va55 ? TCR_E0PD1 : TCR_E0PD0)))
+ goto transfault_l0;
+
+ /* AArch64.S1StartLevel() */
+ stride = wi->pgshift - 3;
+ wi->sl = 3 - (((ia_bits - 1) - wi->pgshift) / stride);
+
+ ps = (wi->regime == TR_EL2 ?
+ FIELD_GET(TCR_EL2_PS_MASK, tcr) : FIELD_GET(TCR_IPS_MASK, tcr));
+
+ wi->max_oa_bits = min(get_kvm_ipa_limit(), ps_to_output_size(ps));
+
+ /* Compute minimal alignment */
+ x = 3 + ia_bits - ((3 - wi->sl) * stride + wi->pgshift);
+
+ wi->baddr = ttbr & TTBRx_EL1_BADDR;
+
+ /* R_VPBBF */
+ if (check_output_size(wi->baddr, wi))
+ goto addrsz;
+
+ wi->baddr &= GENMASK_ULL(wi->max_oa_bits - 1, x);
+
+ return 0;
+
+addrsz: /* Address Size Fault level 0 */
+ fail_s1_walk(wr, ESR_ELx_FSC_ADDRSZ_L(0), false, false);
+ return -EFAULT;
+
+transfault_l0: /* Translation Fault level 0 */
+ fail_s1_walk(wr, ESR_ELx_FSC_FAULT_L(0), false, false);
+ return -EFAULT;
+}
+
+static int walk_s1(struct kvm_vcpu *vcpu, struct s1_walk_info *wi,
+ struct s1_walk_result *wr, u64 va)
+{
+ u64 va_top, va_bottom, baddr, desc;
+ int level, stride, ret;
+
+ level = wi->sl;
+ stride = wi->pgshift - 3;
+ baddr = wi->baddr;
+
+ va_top = get_ia_size(wi) - 1;
+
+ while (1) {
+ u64 index, ipa;
+
+ va_bottom = (3 - level) * stride + wi->pgshift;
+ index = (va & GENMASK_ULL(va_top, va_bottom)) >> (va_bottom - 3);
+
+ ipa = baddr | index;
+
+ if (wi->s2) {
+ struct kvm_s2_trans s2_trans = {};
+
+ ret = kvm_walk_nested_s2(vcpu, ipa, &s2_trans);
+ if (ret) {
+ fail_s1_walk(wr,
+ (s2_trans.esr & ~ESR_ELx_FSC_LEVEL) | level,
+ true, true);
+ return ret;
+ }
+
+ if (!kvm_s2_trans_readable(&s2_trans)) {
+ fail_s1_walk(wr, ESR_ELx_FSC_PERM_L(level),
+ true, true);
+
+ return -EPERM;
+ }
+
+ ipa = kvm_s2_trans_output(&s2_trans);
+ }
+
+ ret = kvm_read_guest(vcpu->kvm, ipa, &desc, sizeof(desc));
+ if (ret) {
+ fail_s1_walk(wr, ESR_ELx_FSC_SEA_TTW(level),
+ true, false);
+ return ret;
+ }
+
+ if (wi->be)
+ desc = be64_to_cpu((__force __be64)desc);
+ else
+ desc = le64_to_cpu((__force __le64)desc);
+
+ /* Invalid descriptor */
+ if (!(desc & BIT(0)))
+ goto transfault;
+
+ /* Block mapping, check validity down the line */
+ if (!(desc & BIT(1)))
+ break;
+
+ /* Page mapping */
+ if (level == 3)
+ break;
+
+ /* Table handling */
+ if (!wi->hpd) {
+ wr->APTable |= FIELD_GET(S1_TABLE_AP, desc);
+ wr->UXNTable |= FIELD_GET(PMD_TABLE_UXN, desc);
+ wr->PXNTable |= FIELD_GET(PMD_TABLE_PXN, desc);
+ }
+
+ baddr = desc & GENMASK_ULL(47, wi->pgshift);
+
+ /* Check for out-of-range OA */
+ if (check_output_size(baddr, wi))
+ goto addrsz;
+
+ /* Prepare for next round */
+ va_top = va_bottom - 1;
+ level++;
+ }
+
+ /* Block mapping, check the validity of the level */
+ if (!(desc & BIT(1))) {
+ bool valid_block = false;
+
+ switch (BIT(wi->pgshift)) {
+ case SZ_4K:
+ valid_block = level == 1 || level == 2;
+ break;
+ case SZ_16K:
+ case SZ_64K:
+ valid_block = level == 2;
+ break;
+ }
+
+ if (!valid_block)
+ goto transfault;
+ }
+
+ if (check_output_size(desc & GENMASK(47, va_bottom), wi))
+ goto addrsz;
+
+ va_bottom += contiguous_bit_shift(desc, wi, level);
+
+ wr->failed = false;
+ wr->level = level;
+ wr->desc = desc;
+ wr->pa = desc & GENMASK(47, va_bottom);
+ wr->pa |= va & GENMASK_ULL(va_bottom - 1, 0);
+
+ return 0;
+
+addrsz:
+ fail_s1_walk(wr, ESR_ELx_FSC_ADDRSZ_L(level), true, false);
+ return -EINVAL;
+transfault:
+ fail_s1_walk(wr, ESR_ELx_FSC_FAULT_L(level), true, false);
+ return -ENOENT;
+}
+
+struct mmu_config {
+ u64 ttbr0;
+ u64 ttbr1;
+ u64 tcr;
+ u64 mair;
+ u64 tcr2;
+ u64 pir;
+ u64 pire0;
+ u64 por_el0;
+ u64 por_el1;
+ u64 sctlr;
+ u64 vttbr;
+ u64 vtcr;
+ u64 hcr;
+};
+
+static void __mmu_config_save(struct mmu_config *config)
+{
+ config->ttbr0 = read_sysreg_el1(SYS_TTBR0);
+ config->ttbr1 = read_sysreg_el1(SYS_TTBR1);
+ config->tcr = read_sysreg_el1(SYS_TCR);
+ config->mair = read_sysreg_el1(SYS_MAIR);
+ if (cpus_have_final_cap(ARM64_HAS_TCR2)) {
+ config->tcr2 = read_sysreg_el1(SYS_TCR2);
+ if (cpus_have_final_cap(ARM64_HAS_S1PIE)) {
+ config->pir = read_sysreg_el1(SYS_PIR);
+ config->pire0 = read_sysreg_el1(SYS_PIRE0);
+ }
+ if (system_supports_poe()) {
+ config->por_el1 = read_sysreg_el1(SYS_POR);
+ config->por_el0 = read_sysreg_s(SYS_POR_EL0);
+ }
+ }
+ config->sctlr = read_sysreg_el1(SYS_SCTLR);
+ config->vttbr = read_sysreg(vttbr_el2);
+ config->vtcr = read_sysreg(vtcr_el2);
+ config->hcr = read_sysreg(hcr_el2);
+}
+
+static void __mmu_config_restore(struct mmu_config *config)
+{
+ write_sysreg(config->hcr, hcr_el2);
+
+ /*
+ * ARM errata 1165522 and 1530923 require TGE to be 1 before
+ * we update the guest state.
+ */
+ asm(ALTERNATIVE("nop", "isb", ARM64_WORKAROUND_SPECULATIVE_AT));
+
+ write_sysreg_el1(config->ttbr0, SYS_TTBR0);
+ write_sysreg_el1(config->ttbr1, SYS_TTBR1);
+ write_sysreg_el1(config->tcr, SYS_TCR);
+ write_sysreg_el1(config->mair, SYS_MAIR);
+ if (cpus_have_final_cap(ARM64_HAS_TCR2)) {
+ write_sysreg_el1(config->tcr2, SYS_TCR2);
+ if (cpus_have_final_cap(ARM64_HAS_S1PIE)) {
+ write_sysreg_el1(config->pir, SYS_PIR);
+ write_sysreg_el1(config->pire0, SYS_PIRE0);
+ }
+ if (system_supports_poe()) {
+ write_sysreg_el1(config->por_el1, SYS_POR);
+ write_sysreg_s(config->por_el0, SYS_POR_EL0);
+ }
+ }
+ write_sysreg_el1(config->sctlr, SYS_SCTLR);
+ write_sysreg(config->vttbr, vttbr_el2);
+ write_sysreg(config->vtcr, vtcr_el2);
+}
+
+static bool at_s1e1p_fast(struct kvm_vcpu *vcpu, u32 op, u64 vaddr)
+{
+ u64 host_pan;
+ bool fail;
+
+ host_pan = read_sysreg_s(SYS_PSTATE_PAN);
+ write_sysreg_s(*vcpu_cpsr(vcpu) & PSTATE_PAN, SYS_PSTATE_PAN);
+
+ switch (op) {
+ case OP_AT_S1E1RP:
+ fail = __kvm_at(OP_AT_S1E1RP, vaddr);
+ break;
+ case OP_AT_S1E1WP:
+ fail = __kvm_at(OP_AT_S1E1WP, vaddr);
+ break;
+ }
+
+ write_sysreg_s(host_pan, SYS_PSTATE_PAN);
+
+ return fail;
+}
+
+#define MEMATTR(ic, oc) (MEMATTR_##oc << 4 | MEMATTR_##ic)
+#define MEMATTR_NC 0b0100
+#define MEMATTR_Wt 0b1000
+#define MEMATTR_Wb 0b1100
+#define MEMATTR_WbRaWa 0b1111
+
+#define MEMATTR_IS_DEVICE(m) (((m) & GENMASK(7, 4)) == 0)
+
+static u8 s2_memattr_to_attr(u8 memattr)
+{
+ memattr &= 0b1111;
+
+ switch (memattr) {
+ case 0b0000:
+ case 0b0001:
+ case 0b0010:
+ case 0b0011:
+ return memattr << 2;
+ case 0b0100:
+ return MEMATTR(Wb, Wb);
+ case 0b0101:
+ return MEMATTR(NC, NC);
+ case 0b0110:
+ return MEMATTR(Wt, NC);
+ case 0b0111:
+ return MEMATTR(Wb, NC);
+ case 0b1000:
+ /* Reserved, assume NC */
+ return MEMATTR(NC, NC);
+ case 0b1001:
+ return MEMATTR(NC, Wt);
+ case 0b1010:
+ return MEMATTR(Wt, Wt);
+ case 0b1011:
+ return MEMATTR(Wb, Wt);
+ case 0b1100:
+ /* Reserved, assume NC */
+ return MEMATTR(NC, NC);
+ case 0b1101:
+ return MEMATTR(NC, Wb);
+ case 0b1110:
+ return MEMATTR(Wt, Wb);
+ case 0b1111:
+ return MEMATTR(Wb, Wb);
+ default:
+ unreachable();
+ }
+}
+
+static u8 combine_s1_s2_attr(u8 s1, u8 s2)
+{
+ bool transient;
+ u8 final = 0;
+
+ /* Upgrade transient s1 to non-transient to simplify things */
+ switch (s1) {
+ case 0b0001 ... 0b0011: /* Normal, Write-Through Transient */
+ transient = true;
+ s1 = MEMATTR_Wt | (s1 & GENMASK(1,0));
+ break;
+ case 0b0101 ... 0b0111: /* Normal, Write-Back Transient */
+ transient = true;
+ s1 = MEMATTR_Wb | (s1 & GENMASK(1,0));
+ break;
+ default:
+ transient = false;
+ }
+
+ /* S2CombineS1AttrHints() */
+ if ((s1 & GENMASK(3, 2)) == MEMATTR_NC ||
+ (s2 & GENMASK(3, 2)) == MEMATTR_NC)
+ final = MEMATTR_NC;
+ else if ((s1 & GENMASK(3, 2)) == MEMATTR_Wt ||
+ (s2 & GENMASK(3, 2)) == MEMATTR_Wt)
+ final = MEMATTR_Wt;
+ else
+ final = MEMATTR_Wb;
+
+ if (final != MEMATTR_NC) {
+ /* Inherit RaWa hints form S1 */
+ if (transient) {
+ switch (s1 & GENMASK(3, 2)) {
+ case MEMATTR_Wt:
+ final = 0;
+ break;
+ case MEMATTR_Wb:
+ final = MEMATTR_NC;
+ break;
+ }
+ }
+
+ final |= s1 & GENMASK(1, 0);
+ }
+
+ return final;
+}
+
+#define ATTR_NSH 0b00
+#define ATTR_RSV 0b01
+#define ATTR_OSH 0b10
+#define ATTR_ISH 0b11
+
+static u8 compute_sh(u8 attr, u64 desc)
+{
+ u8 sh;
+
+ /* Any form of device, as well as NC has SH[1:0]=0b10 */
+ if (MEMATTR_IS_DEVICE(attr) || attr == MEMATTR(NC, NC))
+ return ATTR_OSH;
+
+ sh = FIELD_GET(PTE_SHARED, desc);
+ if (sh == ATTR_RSV) /* Reserved, mapped to NSH */
+ sh = ATTR_NSH;
+
+ return sh;
+}
+
+static u8 combine_sh(u8 s1_sh, u8 s2_sh)
+{
+ if (s1_sh == ATTR_OSH || s2_sh == ATTR_OSH)
+ return ATTR_OSH;
+ if (s1_sh == ATTR_ISH || s2_sh == ATTR_ISH)
+ return ATTR_ISH;
+
+ return ATTR_NSH;
+}
+
+static u64 compute_par_s12(struct kvm_vcpu *vcpu, u64 s1_par,
+ struct kvm_s2_trans *tr)
+{
+ u8 s1_parattr, s2_memattr, final_attr;
+ u64 par;
+
+ /* If S2 has failed to translate, report the damage */
+ if (tr->esr) {
+ par = SYS_PAR_EL1_RES1;
+ par |= SYS_PAR_EL1_F;
+ par |= SYS_PAR_EL1_S;
+ par |= FIELD_PREP(SYS_PAR_EL1_FST, tr->esr);
+ return par;
+ }
+
+ s1_parattr = FIELD_GET(SYS_PAR_EL1_ATTR, s1_par);
+ s2_memattr = FIELD_GET(GENMASK(5, 2), tr->desc);
+
+ if (__vcpu_sys_reg(vcpu, HCR_EL2) & HCR_FWB) {
+ if (!kvm_has_feat(vcpu->kvm, ID_AA64PFR2_EL1, MTEPERM, IMP))
+ s2_memattr &= ~BIT(3);
+
+ /* Combination of R_VRJSW and R_RHWZM */
+ switch (s2_memattr) {
+ case 0b0101:
+ if (MEMATTR_IS_DEVICE(s1_parattr))
+ final_attr = s1_parattr;
+ else
+ final_attr = MEMATTR(NC, NC);
+ break;
+ case 0b0110:
+ case 0b1110:
+ final_attr = MEMATTR(WbRaWa, WbRaWa);
+ break;
+ case 0b0111:
+ case 0b1111:
+ /* Preserve S1 attribute */
+ final_attr = s1_parattr;
+ break;
+ case 0b0100:
+ case 0b1100:
+ case 0b1101:
+ /* Reserved, do something non-silly */
+ final_attr = s1_parattr;
+ break;
+ default:
+ /*
+ * MemAttr[2]=0, Device from S2.
+ *
+ * FWB does not influence the way that stage 1
+ * memory types and attributes are combined
+ * with stage 2 Device type and attributes.
+ */
+ final_attr = min(s2_memattr_to_attr(s2_memattr),
+ s1_parattr);
+ }
+ } else {
+ /* Combination of R_HMNDG, R_TNHFM and R_GQFSF */
+ u8 s2_parattr = s2_memattr_to_attr(s2_memattr);
+
+ if (MEMATTR_IS_DEVICE(s1_parattr) ||
+ MEMATTR_IS_DEVICE(s2_parattr)) {
+ final_attr = min(s1_parattr, s2_parattr);
+ } else {
+ /* At this stage, this is memory vs memory */
+ final_attr = combine_s1_s2_attr(s1_parattr & 0xf,
+ s2_parattr & 0xf);
+ final_attr |= combine_s1_s2_attr(s1_parattr >> 4,
+ s2_parattr >> 4) << 4;
+ }
+ }
+
+ if ((__vcpu_sys_reg(vcpu, HCR_EL2) & HCR_CD) &&
+ !MEMATTR_IS_DEVICE(final_attr))
+ final_attr = MEMATTR(NC, NC);
+
+ par = FIELD_PREP(SYS_PAR_EL1_ATTR, final_attr);
+ par |= tr->output & GENMASK(47, 12);
+ par |= FIELD_PREP(SYS_PAR_EL1_SH,
+ combine_sh(FIELD_GET(SYS_PAR_EL1_SH, s1_par),
+ compute_sh(final_attr, tr->desc)));
+
+ return par;
+}
+
+static u64 compute_par_s1(struct kvm_vcpu *vcpu, struct s1_walk_result *wr,
+ enum trans_regime regime)
+{
+ u64 par;
+
+ if (wr->failed) {
+ par = SYS_PAR_EL1_RES1;
+ par |= SYS_PAR_EL1_F;
+ par |= FIELD_PREP(SYS_PAR_EL1_FST, wr->fst);
+ par |= wr->ptw ? SYS_PAR_EL1_PTW : 0;
+ par |= wr->s2 ? SYS_PAR_EL1_S : 0;
+ } else if (wr->level == S1_MMU_DISABLED) {
+ /* MMU off or HCR_EL2.DC == 1 */
+ par = SYS_PAR_EL1_NSE;
+ par |= wr->pa & GENMASK_ULL(47, 12);
+
+ if (regime == TR_EL10 &&
+ (__vcpu_sys_reg(vcpu, HCR_EL2) & HCR_DC)) {
+ par |= FIELD_PREP(SYS_PAR_EL1_ATTR,
+ MEMATTR(WbRaWa, WbRaWa));
+ par |= FIELD_PREP(SYS_PAR_EL1_SH, ATTR_NSH);
+ } else {
+ par |= FIELD_PREP(SYS_PAR_EL1_ATTR, 0); /* nGnRnE */
+ par |= FIELD_PREP(SYS_PAR_EL1_SH, ATTR_OSH);
+ }
+ } else {
+ u64 mair, sctlr;
+ u8 sh;
+
+ par = SYS_PAR_EL1_NSE;
+
+ mair = (regime == TR_EL10 ?
+ vcpu_read_sys_reg(vcpu, MAIR_EL1) :
+ vcpu_read_sys_reg(vcpu, MAIR_EL2));
+
+ mair >>= FIELD_GET(PTE_ATTRINDX_MASK, wr->desc) * 8;
+ mair &= 0xff;
+
+ sctlr = (regime == TR_EL10 ?
+ vcpu_read_sys_reg(vcpu, SCTLR_EL1) :
+ vcpu_read_sys_reg(vcpu, SCTLR_EL2));
+
+ /* Force NC for memory if SCTLR_ELx.C is clear */
+ if (!(sctlr & SCTLR_EL1_C) && !MEMATTR_IS_DEVICE(mair))
+ mair = MEMATTR(NC, NC);
+
+ par |= FIELD_PREP(SYS_PAR_EL1_ATTR, mair);
+ par |= wr->pa & GENMASK_ULL(47, 12);
+
+ sh = compute_sh(mair, wr->desc);
+ par |= FIELD_PREP(SYS_PAR_EL1_SH, sh);
+ }
+
+ return par;
+}
+
+static bool pan3_enabled(struct kvm_vcpu *vcpu, enum trans_regime regime)
+{
+ u64 sctlr;
+
+ if (!kvm_has_feat(vcpu->kvm, ID_AA64MMFR1_EL1, PAN, PAN3))
+ return false;
+
+ if (s1pie_enabled(vcpu, regime))
+ return true;
+
+ if (regime == TR_EL10)
+ sctlr = vcpu_read_sys_reg(vcpu, SCTLR_EL1);
+ else
+ sctlr = vcpu_read_sys_reg(vcpu, SCTLR_EL2);
+
+ return sctlr & SCTLR_EL1_EPAN;
+}
+
+static void compute_s1_direct_permissions(struct kvm_vcpu *vcpu,
+ struct s1_walk_info *wi,
+ struct s1_walk_result *wr)
+{
+ bool wxn;
+
+ /* Non-hierarchical part of AArch64.S1DirectBasePermissions() */
+ if (wi->regime != TR_EL2) {
+ switch (FIELD_GET(PTE_USER | PTE_RDONLY, wr->desc)) {
+ case 0b00:
+ wr->pr = wr->pw = true;
+ wr->ur = wr->uw = false;
+ break;
+ case 0b01:
+ wr->pr = wr->pw = wr->ur = wr->uw = true;
+ break;
+ case 0b10:
+ wr->pr = true;
+ wr->pw = wr->ur = wr->uw = false;
+ break;
+ case 0b11:
+ wr->pr = wr->ur = true;
+ wr->pw = wr->uw = false;
+ break;
+ }
+
+ /* We don't use px for anything yet, but hey... */
+ wr->px = !((wr->desc & PTE_PXN) || wr->uw);
+ wr->ux = !(wr->desc & PTE_UXN);
+ } else {
+ wr->ur = wr->uw = wr->ux = false;
+
+ if (!(wr->desc & PTE_RDONLY)) {
+ wr->pr = wr->pw = true;
+ } else {
+ wr->pr = true;
+ wr->pw = false;
+ }
+
+ /* XN maps to UXN */
+ wr->px = !(wr->desc & PTE_UXN);
+ }
+
+ switch (wi->regime) {
+ case TR_EL2:
+ case TR_EL20:
+ wxn = (vcpu_read_sys_reg(vcpu, SCTLR_EL2) & SCTLR_ELx_WXN);
+ break;
+ case TR_EL10:
+ wxn = (__vcpu_sys_reg(vcpu, SCTLR_EL1) & SCTLR_ELx_WXN);
+ break;
+ }
+
+ wr->pwxn = wr->uwxn = wxn;
+ wr->pov = wi->poe;
+ wr->uov = wi->e0poe;
+}
+
+static void compute_s1_hierarchical_permissions(struct kvm_vcpu *vcpu,
+ struct s1_walk_info *wi,
+ struct s1_walk_result *wr)
+{
+ /* Hierarchical part of AArch64.S1DirectBasePermissions() */
+ if (wi->regime != TR_EL2) {
+ switch (wr->APTable) {
+ case 0b00:
+ break;
+ case 0b01:
+ wr->ur = wr->uw = false;
+ break;
+ case 0b10:
+ wr->pw = wr->uw = false;
+ break;
+ case 0b11:
+ wr->pw = wr->ur = wr->uw = false;
+ break;
+ }
+
+ wr->px &= !wr->PXNTable;
+ wr->ux &= !wr->UXNTable;
+ } else {
+ if (wr->APTable & BIT(1))
+ wr->pw = false;
+
+ /* XN maps to UXN */
+ wr->px &= !wr->UXNTable;
+ }
+}
+
+#define perm_idx(v, r, i) ((vcpu_read_sys_reg((v), (r)) >> ((i) * 4)) & 0xf)
+
+#define set_priv_perms(wr, r, w, x) \
+ do { \
+ (wr)->pr = (r); \
+ (wr)->pw = (w); \
+ (wr)->px = (x); \
+ } while (0)
+
+#define set_unpriv_perms(wr, r, w, x) \
+ do { \
+ (wr)->ur = (r); \
+ (wr)->uw = (w); \
+ (wr)->ux = (x); \
+ } while (0)
+
+#define set_priv_wxn(wr, v) \
+ do { \
+ (wr)->pwxn = (v); \
+ } while (0)
+
+#define set_unpriv_wxn(wr, v) \
+ do { \
+ (wr)->uwxn = (v); \
+ } while (0)
+
+/* Similar to AArch64.S1IndirectBasePermissions(), without GCS */
+#define set_perms(w, wr, ip) \
+ do { \
+ /* R_LLZDZ */ \
+ switch ((ip)) { \
+ case 0b0000: \
+ set_ ## w ## _perms((wr), false, false, false); \
+ break; \
+ case 0b0001: \
+ set_ ## w ## _perms((wr), true , false, false); \
+ break; \
+ case 0b0010: \
+ set_ ## w ## _perms((wr), false, false, true ); \
+ break; \
+ case 0b0011: \
+ set_ ## w ## _perms((wr), true , false, true ); \
+ break; \
+ case 0b0100: \
+ set_ ## w ## _perms((wr), false, false, false); \
+ break; \
+ case 0b0101: \
+ set_ ## w ## _perms((wr), true , true , false); \
+ break; \
+ case 0b0110: \
+ set_ ## w ## _perms((wr), true , true , true ); \
+ break; \
+ case 0b0111: \
+ set_ ## w ## _perms((wr), true , true , true ); \
+ break; \
+ case 0b1000: \
+ set_ ## w ## _perms((wr), true , false, false); \
+ break; \
+ case 0b1001: \
+ set_ ## w ## _perms((wr), true , false, false); \
+ break; \
+ case 0b1010: \
+ set_ ## w ## _perms((wr), true , false, true ); \
+ break; \
+ case 0b1011: \
+ set_ ## w ## _perms((wr), false, false, false); \
+ break; \
+ case 0b1100: \
+ set_ ## w ## _perms((wr), true , true , false); \
+ break; \
+ case 0b1101: \
+ set_ ## w ## _perms((wr), false, false, false); \
+ break; \
+ case 0b1110: \
+ set_ ## w ## _perms((wr), true , true , true ); \
+ break; \
+ case 0b1111: \
+ set_ ## w ## _perms((wr), false, false, false); \
+ break; \
+ } \
+ \
+ /* R_HJYGR */ \
+ set_ ## w ## _wxn((wr), ((ip) == 0b0110)); \
+ \
+ } while (0)
+
+static void compute_s1_indirect_permissions(struct kvm_vcpu *vcpu,
+ struct s1_walk_info *wi,
+ struct s1_walk_result *wr)
+{
+ u8 up, pp, idx;
+
+ idx = pte_pi_index(wr->desc);
+
+ switch (wi->regime) {
+ case TR_EL10:
+ pp = perm_idx(vcpu, PIR_EL1, idx);
+ up = perm_idx(vcpu, PIRE0_EL1, idx);
+ break;
+ case TR_EL20:
+ pp = perm_idx(vcpu, PIR_EL2, idx);
+ up = perm_idx(vcpu, PIRE0_EL2, idx);
+ break;
+ case TR_EL2:
+ pp = perm_idx(vcpu, PIR_EL2, idx);
+ up = 0;
+ break;
+ }
+
+ set_perms(priv, wr, pp);
+
+ if (wi->regime != TR_EL2)
+ set_perms(unpriv, wr, up);
+ else
+ set_unpriv_perms(wr, false, false, false);
+
+ wr->pov = wi->poe && !(pp & BIT(3));
+ wr->uov = wi->e0poe && !(up & BIT(3));
+
+ /* R_VFPJF */
+ if (wr->px && wr->uw) {
+ set_priv_perms(wr, false, false, false);
+ set_unpriv_perms(wr, false, false, false);
+ }
+}
+
+static void compute_s1_overlay_permissions(struct kvm_vcpu *vcpu,
+ struct s1_walk_info *wi,
+ struct s1_walk_result *wr)
+{
+ u8 idx, pov_perms, uov_perms;
+
+ idx = FIELD_GET(PTE_PO_IDX_MASK, wr->desc);
+
+ switch (wi->regime) {
+ case TR_EL10:
+ pov_perms = perm_idx(vcpu, POR_EL1, idx);
+ uov_perms = perm_idx(vcpu, POR_EL0, idx);
+ break;
+ case TR_EL20:
+ pov_perms = perm_idx(vcpu, POR_EL2, idx);
+ uov_perms = perm_idx(vcpu, POR_EL0, idx);
+ break;
+ case TR_EL2:
+ pov_perms = perm_idx(vcpu, POR_EL2, idx);
+ uov_perms = 0;
+ break;
+ }
+
+ if (pov_perms & ~POE_RWX)
+ pov_perms = POE_NONE;
+
+ if (wi->poe && wr->pov) {
+ wr->pr &= pov_perms & POE_R;
+ wr->pw &= pov_perms & POE_W;
+ wr->px &= pov_perms & POE_X;
+ }
+
+ if (uov_perms & ~POE_RWX)
+ uov_perms = POE_NONE;
+
+ if (wi->e0poe && wr->uov) {
+ wr->ur &= uov_perms & POE_R;
+ wr->uw &= uov_perms & POE_W;
+ wr->ux &= uov_perms & POE_X;
+ }
+}
+
+static void compute_s1_permissions(struct kvm_vcpu *vcpu,
+ struct s1_walk_info *wi,
+ struct s1_walk_result *wr)
+{
+ bool pan;
+
+ if (!s1pie_enabled(vcpu, wi->regime))
+ compute_s1_direct_permissions(vcpu, wi, wr);
+ else
+ compute_s1_indirect_permissions(vcpu, wi, wr);
+
+ if (!wi->hpd)
+ compute_s1_hierarchical_permissions(vcpu, wi, wr);
+
+ if (wi->poe || wi->e0poe)
+ compute_s1_overlay_permissions(vcpu, wi, wr);
+
+ /* R_QXXPC */
+ if (wr->pwxn) {
+ if (!wr->pov && wr->pw)
+ wr->px = false;
+ if (wr->pov && wr->px)
+ wr->pw = false;
+ }
+
+ /* R_NPBXC */
+ if (wr->uwxn) {
+ if (!wr->uov && wr->uw)
+ wr->ux = false;
+ if (wr->uov && wr->ux)
+ wr->uw = false;
+ }
+
+ pan = wi->pan && (wr->ur || wr->uw ||
+ (pan3_enabled(vcpu, wi->regime) && wr->ux));
+ wr->pw &= !pan;
+ wr->pr &= !pan;
+}
+
+static u64 handle_at_slow(struct kvm_vcpu *vcpu, u32 op, u64 vaddr)
+{
+ struct s1_walk_result wr = {};
+ struct s1_walk_info wi = {};
+ bool perm_fail = false;
+ int ret, idx;
+
+ ret = setup_s1_walk(vcpu, op, &wi, &wr, vaddr);
+ if (ret)
+ goto compute_par;
+
+ if (wr.level == S1_MMU_DISABLED)
+ goto compute_par;
+
+ idx = srcu_read_lock(&vcpu->kvm->srcu);
+
+ ret = walk_s1(vcpu, &wi, &wr, vaddr);
+
+ srcu_read_unlock(&vcpu->kvm->srcu, idx);
+
+ if (ret)
+ goto compute_par;
+
+ compute_s1_permissions(vcpu, &wi, &wr);
+
+ switch (op) {
+ case OP_AT_S1E1RP:
+ case OP_AT_S1E1R:
+ case OP_AT_S1E2R:
+ perm_fail = !wr.pr;
+ break;
+ case OP_AT_S1E1WP:
+ case OP_AT_S1E1W:
+ case OP_AT_S1E2W:
+ perm_fail = !wr.pw;
+ break;
+ case OP_AT_S1E0R:
+ perm_fail = !wr.ur;
+ break;
+ case OP_AT_S1E0W:
+ perm_fail = !wr.uw;
+ break;
+ case OP_AT_S1E1A:
+ case OP_AT_S1E2A:
+ break;
+ default:
+ BUG();
+ }
+
+ if (perm_fail)
+ fail_s1_walk(&wr, ESR_ELx_FSC_PERM_L(wr.level), false, false);
+
+compute_par:
+ return compute_par_s1(vcpu, &wr, wi.regime);
+}
+
+/*
+ * Return the PAR_EL1 value as the result of a valid translation.
+ *
+ * If the translation is unsuccessful, the value may only contain
+ * PAR_EL1.F, and cannot be taken at face value. It isn't an
+ * indication of the translation having failed, only that the fast
+ * path did not succeed, *unless* it indicates a S1 permission fault.
+ */
+static u64 __kvm_at_s1e01_fast(struct kvm_vcpu *vcpu, u32 op, u64 vaddr)
+{
+ struct mmu_config config;
+ struct kvm_s2_mmu *mmu;
+ bool fail;
+ u64 par;
+
+ par = SYS_PAR_EL1_F;
+
+ /*
+ * We've trapped, so everything is live on the CPU. As we will
+ * be switching contexts behind everybody's back, disable
+ * interrupts while holding the mmu lock.
+ */
+ guard(write_lock_irqsave)(&vcpu->kvm->mmu_lock);
+
+ /*
+ * If HCR_EL2.{E2H,TGE} == {1,1}, the MMU context is already
+ * the right one (as we trapped from vEL2). If not, save the
+ * full MMU context.
+ */
+ if (vcpu_el2_e2h_is_set(vcpu) && vcpu_el2_tge_is_set(vcpu))
+ goto skip_mmu_switch;
+
+ /*
+ * Obtaining the S2 MMU for a L2 is horribly racy, and we may not
+ * find it (recycled by another vcpu, for example). When this
+ * happens, admit defeat immediately and use the SW (slow) path.
+ */
+ mmu = lookup_s2_mmu(vcpu);
+ if (!mmu)
+ return par;
+
+ __mmu_config_save(&config);
+
+ write_sysreg_el1(vcpu_read_sys_reg(vcpu, TTBR0_EL1), SYS_TTBR0);
+ write_sysreg_el1(vcpu_read_sys_reg(vcpu, TTBR1_EL1), SYS_TTBR1);
+ write_sysreg_el1(vcpu_read_sys_reg(vcpu, TCR_EL1), SYS_TCR);
+ write_sysreg_el1(vcpu_read_sys_reg(vcpu, MAIR_EL1), SYS_MAIR);
+ if (kvm_has_tcr2(vcpu->kvm)) {
+ write_sysreg_el1(vcpu_read_sys_reg(vcpu, TCR2_EL1), SYS_TCR2);
+ if (kvm_has_s1pie(vcpu->kvm)) {
+ write_sysreg_el1(vcpu_read_sys_reg(vcpu, PIR_EL1), SYS_PIR);
+ write_sysreg_el1(vcpu_read_sys_reg(vcpu, PIRE0_EL1), SYS_PIRE0);
+ }
+ if (kvm_has_s1poe(vcpu->kvm)) {
+ write_sysreg_el1(vcpu_read_sys_reg(vcpu, POR_EL1), SYS_POR);
+ write_sysreg_s(vcpu_read_sys_reg(vcpu, POR_EL0), SYS_POR_EL0);
+ }
+ }
+ write_sysreg_el1(vcpu_read_sys_reg(vcpu, SCTLR_EL1), SYS_SCTLR);
+ __load_stage2(mmu, mmu->arch);
+
+skip_mmu_switch:
+ /* Clear TGE, enable S2 translation, we're rolling */
+ write_sysreg((config.hcr & ~HCR_TGE) | HCR_VM, hcr_el2);
+ isb();
+
+ switch (op) {
+ case OP_AT_S1E1RP:
+ case OP_AT_S1E1WP:
+ fail = at_s1e1p_fast(vcpu, op, vaddr);
+ break;
+ case OP_AT_S1E1R:
+ fail = __kvm_at(OP_AT_S1E1R, vaddr);
+ break;
+ case OP_AT_S1E1W:
+ fail = __kvm_at(OP_AT_S1E1W, vaddr);
+ break;
+ case OP_AT_S1E0R:
+ fail = __kvm_at(OP_AT_S1E0R, vaddr);
+ break;
+ case OP_AT_S1E0W:
+ fail = __kvm_at(OP_AT_S1E0W, vaddr);
+ break;
+ case OP_AT_S1E1A:
+ fail = __kvm_at(OP_AT_S1E1A, vaddr);
+ break;
+ default:
+ WARN_ON_ONCE(1);
+ fail = true;
+ break;
+ }
+
+ if (!fail)
+ par = read_sysreg_par();
+
+ if (!(vcpu_el2_e2h_is_set(vcpu) && vcpu_el2_tge_is_set(vcpu)))
+ __mmu_config_restore(&config);
+
+ return par;
+}
+
+static bool par_check_s1_perm_fault(u64 par)
+{
+ u8 fst = FIELD_GET(SYS_PAR_EL1_FST, par);
+
+ return ((fst & ESR_ELx_FSC_TYPE) == ESR_ELx_FSC_PERM &&
+ !(par & SYS_PAR_EL1_S));
+}
+
+void __kvm_at_s1e01(struct kvm_vcpu *vcpu, u32 op, u64 vaddr)
+{
+ u64 par = __kvm_at_s1e01_fast(vcpu, op, vaddr);
+
+ /*
+ * If PAR_EL1 reports that AT failed on a S1 permission fault, we
+ * know for sure that the PTW was able to walk the S1 tables and
+ * there's nothing else to do.
+ *
+ * If AT failed for any other reason, then we must walk the guest S1
+ * to emulate the instruction.
+ */
+ if ((par & SYS_PAR_EL1_F) && !par_check_s1_perm_fault(par))
+ par = handle_at_slow(vcpu, op, vaddr);
+
+ vcpu_write_sys_reg(vcpu, par, PAR_EL1);
+}
+
+void __kvm_at_s1e2(struct kvm_vcpu *vcpu, u32 op, u64 vaddr)
+{
+ u64 par;
+
+ /*
+ * We've trapped, so everything is live on the CPU. As we will be
+ * switching context behind everybody's back, disable interrupts...
+ */
+ scoped_guard(write_lock_irqsave, &vcpu->kvm->mmu_lock) {
+ u64 val, hcr;
+ bool fail;
+
+ val = hcr = read_sysreg(hcr_el2);
+ val &= ~HCR_TGE;
+ val |= HCR_VM;
+
+ if (!vcpu_el2_e2h_is_set(vcpu))
+ val |= HCR_NV | HCR_NV1;
+
+ write_sysreg(val, hcr_el2);
+ isb();
+
+ par = SYS_PAR_EL1_F;
+
+ switch (op) {
+ case OP_AT_S1E2R:
+ fail = __kvm_at(OP_AT_S1E1R, vaddr);
+ break;
+ case OP_AT_S1E2W:
+ fail = __kvm_at(OP_AT_S1E1W, vaddr);
+ break;
+ case OP_AT_S1E2A:
+ fail = __kvm_at(OP_AT_S1E1A, vaddr);
+ break;
+ default:
+ WARN_ON_ONCE(1);
+ fail = true;
+ }
+
+ isb();
+
+ if (!fail)
+ par = read_sysreg_par();
+
+ write_sysreg(hcr, hcr_el2);
+ isb();
+ }
+
+ /* We failed the translation, let's replay it in slow motion */
+ if ((par & SYS_PAR_EL1_F) && !par_check_s1_perm_fault(par))
+ par = handle_at_slow(vcpu, op, vaddr);
+
+ vcpu_write_sys_reg(vcpu, par, PAR_EL1);
+}
+
+void __kvm_at_s12(struct kvm_vcpu *vcpu, u32 op, u64 vaddr)
+{
+ struct kvm_s2_trans out = {};
+ u64 ipa, par;
+ bool write;
+ int ret;
+
+ /* Do the stage-1 translation */
+ switch (op) {
+ case OP_AT_S12E1R:
+ op = OP_AT_S1E1R;
+ write = false;
+ break;
+ case OP_AT_S12E1W:
+ op = OP_AT_S1E1W;
+ write = true;
+ break;
+ case OP_AT_S12E0R:
+ op = OP_AT_S1E0R;
+ write = false;
+ break;
+ case OP_AT_S12E0W:
+ op = OP_AT_S1E0W;
+ write = true;
+ break;
+ default:
+ WARN_ON_ONCE(1);
+ return;
+ }
+
+ __kvm_at_s1e01(vcpu, op, vaddr);
+ par = vcpu_read_sys_reg(vcpu, PAR_EL1);
+ if (par & SYS_PAR_EL1_F)
+ return;
+
+ /*
+ * If we only have a single stage of translation (E2H=0 or
+ * TGE=1), exit early. Same thing if {VM,DC}=={0,0}.
+ */
+ if (!vcpu_el2_e2h_is_set(vcpu) || vcpu_el2_tge_is_set(vcpu) ||
+ !(vcpu_read_sys_reg(vcpu, HCR_EL2) & (HCR_VM | HCR_DC)))
+ return;
+
+ /* Do the stage-2 translation */
+ ipa = (par & GENMASK_ULL(47, 12)) | (vaddr & GENMASK_ULL(11, 0));
+ out.esr = 0;
+ ret = kvm_walk_nested_s2(vcpu, ipa, &out);
+ if (ret < 0)
+ return;
+
+ /* Check the access permission */
+ if (!out.esr &&
+ ((!write && !out.readable) || (write && !out.writable)))
+ out.esr = ESR_ELx_FSC_PERM_L(out.level & 0x3);
+
+ par = compute_par_s12(vcpu, par, &out);
+ vcpu_write_sys_reg(vcpu, par, PAR_EL1);
+}