root/arch/arm64/include/asm/kvm_nested.h
/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __ARM64_KVM_NESTED_H
#define __ARM64_KVM_NESTED_H

#include <linux/bitfield.h>
#include <linux/kvm_host.h>
#include <asm/kvm_emulate.h>
#include <asm/kvm_pgtable.h>

static inline bool vcpu_has_nv(const struct kvm_vcpu *vcpu)
{
        return (!__is_defined(__KVM_NVHE_HYPERVISOR__) &&
                cpus_have_final_cap(ARM64_HAS_NESTED_VIRT) &&
                vcpu_has_feature(vcpu, KVM_ARM_VCPU_HAS_EL2));
}

/* Translation helpers from non-VHE EL2 to EL1 */
static inline u64 tcr_el2_ps_to_tcr_el1_ips(u64 tcr_el2)
{
        return (u64)FIELD_GET(TCR_EL2_PS_MASK, tcr_el2) << TCR_IPS_SHIFT;
}

static inline u64 translate_tcr_el2_to_tcr_el1(u64 tcr)
{
        return TCR_EPD1_MASK |                          /* disable TTBR1_EL1 */
               ((tcr & TCR_EL2_TBI) ? TCR_TBI0 : 0) |
               tcr_el2_ps_to_tcr_el1_ips(tcr) |
               (tcr & TCR_EL2_TG0_MASK) |
               (tcr & TCR_EL2_ORGN0_MASK) |
               (tcr & TCR_EL2_IRGN0_MASK) |
               (tcr & TCR_EL2_T0SZ_MASK);
}

static inline u64 translate_cptr_el2_to_cpacr_el1(u64 cptr_el2)
{
        u64 cpacr_el1 = CPACR_EL1_RES1;

        if (cptr_el2 & CPTR_EL2_TTA)
                cpacr_el1 |= CPACR_EL1_TTA;
        if (!(cptr_el2 & CPTR_EL2_TFP))
                cpacr_el1 |= CPACR_EL1_FPEN;
        if (!(cptr_el2 & CPTR_EL2_TZ))
                cpacr_el1 |= CPACR_EL1_ZEN;

        cpacr_el1 |= cptr_el2 & (CPTR_EL2_TCPAC | CPTR_EL2_TAM);

        return cpacr_el1;
}

static inline u64 translate_sctlr_el2_to_sctlr_el1(u64 val)
{
        /* Only preserve the minimal set of bits we support */
        val &= (SCTLR_ELx_M | SCTLR_ELx_A | SCTLR_ELx_C | SCTLR_ELx_SA |
                SCTLR_ELx_I | SCTLR_ELx_IESB | SCTLR_ELx_WXN | SCTLR_ELx_EE);
        val |= SCTLR_EL1_RES1;

        return val;
}

static inline u64 translate_ttbr0_el2_to_ttbr0_el1(u64 ttbr0)
{
        /* Clear the ASID field */
        return ttbr0 & ~GENMASK_ULL(63, 48);
}

extern bool forward_smc_trap(struct kvm_vcpu *vcpu);
extern bool forward_debug_exception(struct kvm_vcpu *vcpu);
extern void kvm_init_nested(struct kvm *kvm);
extern int kvm_vcpu_init_nested(struct kvm_vcpu *vcpu);
extern void kvm_init_nested_s2_mmu(struct kvm_s2_mmu *mmu);
extern struct kvm_s2_mmu *lookup_s2_mmu(struct kvm_vcpu *vcpu);

union tlbi_info;

extern void kvm_s2_mmu_iterate_by_vmid(struct kvm *kvm, u16 vmid,
                                       const union tlbi_info *info,
                                       void (*)(struct kvm_s2_mmu *,
                                                const union tlbi_info *));
extern void kvm_vcpu_load_hw_mmu(struct kvm_vcpu *vcpu);
extern void kvm_vcpu_put_hw_mmu(struct kvm_vcpu *vcpu);

extern void check_nested_vcpu_requests(struct kvm_vcpu *vcpu);
extern void kvm_nested_flush_hwstate(struct kvm_vcpu *vcpu);
extern void kvm_nested_sync_hwstate(struct kvm_vcpu *vcpu);

extern void kvm_nested_setup_mdcr_el2(struct kvm_vcpu *vcpu);

struct kvm_s2_trans {
        phys_addr_t output;
        unsigned long block_size;
        bool writable;
        bool readable;
        int level;
        u32 esr;
        u64 desc;
};

static inline phys_addr_t kvm_s2_trans_output(struct kvm_s2_trans *trans)
{
        return trans->output;
}

static inline unsigned long kvm_s2_trans_size(struct kvm_s2_trans *trans)
{
        return trans->block_size;
}

static inline u32 kvm_s2_trans_esr(struct kvm_s2_trans *trans)
{
        return trans->esr;
}

static inline bool kvm_s2_trans_readable(struct kvm_s2_trans *trans)
{
        return trans->readable;
}

static inline bool kvm_s2_trans_writable(struct kvm_s2_trans *trans)
{
        return trans->writable;
}

static inline bool kvm_has_xnx(struct kvm *kvm)
{
        return cpus_have_final_cap(ARM64_HAS_XNX) &&
                kvm_has_feat(kvm, ID_AA64MMFR1_EL1, XNX, IMP);
}

static inline bool kvm_s2_trans_exec_el0(struct kvm *kvm, struct kvm_s2_trans *trans)
{
        u8 xn = FIELD_GET(KVM_PTE_LEAF_ATTR_HI_S2_XN, trans->desc);

        if (!kvm_has_xnx(kvm))
                xn &= FIELD_PREP(KVM_PTE_LEAF_ATTR_HI_S2_XN, 0b10);

        switch (xn) {
        case 0b00:
        case 0b01:
                return true;
        default:
                return false;
        }
}

static inline bool kvm_s2_trans_exec_el1(struct kvm *kvm, struct kvm_s2_trans *trans)
{
        u8 xn = FIELD_GET(KVM_PTE_LEAF_ATTR_HI_S2_XN, trans->desc);

        if (!kvm_has_xnx(kvm))
                xn &= FIELD_PREP(KVM_PTE_LEAF_ATTR_HI_S2_XN, 0b10);

        switch (xn) {
        case 0b00:
        case 0b11:
                return true;
        default:
                return false;
        }
}

extern int kvm_walk_nested_s2(struct kvm_vcpu *vcpu, phys_addr_t gipa,
                              struct kvm_s2_trans *result);
extern int kvm_s2_handle_perm_fault(struct kvm_vcpu *vcpu,
                                    struct kvm_s2_trans *trans);
extern int kvm_inject_s2_fault(struct kvm_vcpu *vcpu, u64 esr_el2);
extern void kvm_nested_s2_wp(struct kvm *kvm);
extern void kvm_nested_s2_unmap(struct kvm *kvm, bool may_block);
extern void kvm_nested_s2_flush(struct kvm *kvm);

unsigned long compute_tlb_inval_range(struct kvm_s2_mmu *mmu, u64 val);

static inline bool kvm_supported_tlbi_s1e1_op(struct kvm_vcpu *vpcu, u32 instr)
{
        struct kvm *kvm = vpcu->kvm;
        u8 CRm = sys_reg_CRm(instr);

        if (!(sys_reg_Op0(instr) == TLBI_Op0 &&
              sys_reg_Op1(instr) == TLBI_Op1_EL1))
                return false;

        if (!(sys_reg_CRn(instr) == TLBI_CRn_XS ||
              (sys_reg_CRn(instr) == TLBI_CRn_nXS &&
               kvm_has_feat(kvm, ID_AA64ISAR1_EL1, XS, IMP))))
                return false;

        if (CRm == TLBI_CRm_nROS &&
            !kvm_has_feat(kvm, ID_AA64ISAR0_EL1, TLB, OS))
                return false;

        if ((CRm == TLBI_CRm_RIS || CRm == TLBI_CRm_ROS ||
             CRm == TLBI_CRm_RNS) &&
            !kvm_has_feat(kvm, ID_AA64ISAR0_EL1, TLB, RANGE))
                return false;

        return true;
}

static inline bool kvm_supported_tlbi_s1e2_op(struct kvm_vcpu *vpcu, u32 instr)
{
        struct kvm *kvm = vpcu->kvm;
        u8 CRm = sys_reg_CRm(instr);

        if (!(sys_reg_Op0(instr) == TLBI_Op0 &&
              sys_reg_Op1(instr) == TLBI_Op1_EL2))
                return false;

        if (!(sys_reg_CRn(instr) == TLBI_CRn_XS ||
              (sys_reg_CRn(instr) == TLBI_CRn_nXS &&
               kvm_has_feat(kvm, ID_AA64ISAR1_EL1, XS, IMP))))
                return false;

        if (CRm == TLBI_CRm_IPAIS || CRm == TLBI_CRm_IPAONS)
                return false;

        if (CRm == TLBI_CRm_nROS &&
            !kvm_has_feat(kvm, ID_AA64ISAR0_EL1, TLB, OS))
                return false;

        if ((CRm == TLBI_CRm_RIS || CRm == TLBI_CRm_ROS ||
             CRm == TLBI_CRm_RNS) &&
            !kvm_has_feat(kvm, ID_AA64ISAR0_EL1, TLB, RANGE))
                return false;

        return true;
}

int kvm_init_nv_sysregs(struct kvm_vcpu *vcpu);
u64 limit_nv_id_reg(struct kvm *kvm, u32 reg, u64 val);

#ifdef CONFIG_ARM64_PTR_AUTH
bool kvm_auth_eretax(struct kvm_vcpu *vcpu, u64 *elr);
#else
static inline bool kvm_auth_eretax(struct kvm_vcpu *vcpu, u64 *elr)
{
        /* We really should never execute this... */
        WARN_ON_ONCE(1);
        *elr = 0xbad9acc0debadbad;
        return false;
}
#endif

#define KVM_NV_GUEST_MAP_SZ     (KVM_PGTABLE_PROT_SW1 | KVM_PGTABLE_PROT_SW0)

static inline u64 kvm_encode_nested_level(struct kvm_s2_trans *trans)
{
        return FIELD_PREP(KVM_NV_GUEST_MAP_SZ, trans->level);
}

/* Adjust alignment for the contiguous bit as per StageOA() */
#define contiguous_bit_shift(d, wi, l)                                  \
        ({                                                              \
                u8 shift = 0;                                           \
                                                                        \
                if ((d) & PTE_CONT) {                                   \
                        switch (BIT((wi)->pgshift)) {                   \
                        case SZ_4K:                                     \
                                shift = 4;                              \
                                break;                                  \
                        case SZ_16K:                                    \
                                shift = (l) == 2 ? 5 : 7;               \
                                break;                                  \
                        case SZ_64K:                                    \
                                shift = 5;                              \
                                break;                                  \
                        }                                               \
                }                                                       \
                                                                        \
                shift;                                                  \
        })

static inline u64 decode_range_tlbi(u64 val, u64 *range, u16 *asid)
{
        u64 base, tg, num, scale;
        int shift;

        tg      = FIELD_GET(GENMASK(47, 46), val);

        switch(tg) {
        case 1:
                shift = 12;
                break;
        case 2:
                shift = 14;
                break;
        case 3:
        default:                /* IMPDEF: handle tg==0 as 64k */
                shift = 16;
                break;
        }

        base    = (val & GENMASK(36, 0)) << shift;

        if (asid)
                *asid = FIELD_GET(TLBIR_ASID_MASK, val);

        scale   = FIELD_GET(GENMASK(45, 44), val);
        num     = FIELD_GET(GENMASK(43, 39), val);
        *range  = __TLBI_RANGE_PAGES(num, scale) << shift;

        return base;
}

static inline unsigned int ps_to_output_size(unsigned int ps, bool pa52bit)
{
        switch (ps) {
        case 0: return 32;
        case 1: return 36;
        case 2: return 40;
        case 3: return 42;
        case 4: return 44;
        case 5: return 48;
        case 6: if (pa52bit)
                        return 52;
                fallthrough;
        default:
                return 48;
        }
}

enum trans_regime {
        TR_EL10,
        TR_EL20,
        TR_EL2,
};

struct s1_walk_info;

struct s1_walk_context {
        struct s1_walk_info     *wi;
        u64                     table_ipa;
        int                     level;
};

struct s1_walk_filter {
        int     (*fn)(struct s1_walk_context *, void *);
        void    *priv;
};

struct s1_walk_info {
        struct s1_walk_filter   *filter;
        u64                     baddr;
        enum trans_regime       regime;
        unsigned int            max_oa_bits;
        unsigned int            pgshift;
        unsigned int            txsz;
        int                     sl;
        u8                      sh;
        bool                    as_el0;
        bool                    hpd;
        bool                    e0poe;
        bool                    poe;
        bool                    pan;
        bool                    be;
        bool                    s2;
        bool                    pa52bit;
        bool                    ha;
};

struct s1_walk_result {
        union {
                struct {
                        u64     desc;
                        u64     pa;
                        s8      level;
                        u8      APTable;
                        bool    nG;
                        u16     asid;
                        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;
};

int __kvm_translate_va(struct kvm_vcpu *vcpu, struct s1_walk_info *wi,
                       struct s1_walk_result *wr, u64 va);
int __kvm_find_s1_desc_level(struct kvm_vcpu *vcpu, u64 va, u64 ipa,
                             int *level);

/* VNCR management */
int kvm_vcpu_allocate_vncr_tlb(struct kvm_vcpu *vcpu);
int kvm_handle_vncr_abort(struct kvm_vcpu *vcpu);
void kvm_handle_s1e2_tlbi(struct kvm_vcpu *vcpu, u32 inst, u64 val);

u16 get_asid_by_regime(struct kvm_vcpu *vcpu, enum trans_regime regime);

#define vncr_fixmap(c)                                          \
        ({                                                      \
                u32 __c = (c);                                  \
                BUG_ON(__c >= NR_CPUS);                         \
                (FIX_VNCR - __c);                               \
        })

int __kvm_at_swap_desc(struct kvm *kvm, gpa_t ipa, u64 old, u64 new);

#endif /* __ARM64_KVM_NESTED_H */