/* SPDX-License-Identifier: GPL-2.0 */

/*
 * Linux-specific definitions for managing interactions with Microsoft's
 * Hyper-V hypervisor. The definitions in this file are architecture
 * independent. See arch/<arch>/include/asm/mshyperv.h for definitions
 * that are specific to architecture <arch>.
 *
 * Definitions that are derived from Hyper-V code or headers should not go in
 * this file, but should instead go in the relevant files in include/hyperv.
 *
 * Copyright (C) 2019, Microsoft, Inc.
 *
 * Author : Michael Kelley <mikelley@microsoft.com>
 */

#ifndef _ASM_GENERIC_MSHYPERV_H
#define _ASM_GENERIC_MSHYPERV_H

#include <linux/types.h>
#include <linux/atomic.h>
#include <linux/bitops.h>
#include <acpi/acpi_numa.h>
#include <linux/cpumask.h>
#include <linux/nmi.h>
#include <asm/ptrace.h>
#include <hyperv/hvhdk.h>

#define VTPM_BASE_ADDRESS 0xfed40000

enum hv_partition_type {
        HV_PARTITION_TYPE_GUEST,
        HV_PARTITION_TYPE_ROOT,
        HV_PARTITION_TYPE_L1VH,
};

struct ms_hyperv_info {
        u32 features;
        u32 priv_high;
        u32 ext_features;
        u32 misc_features;
        u32 hints;
        u32 nested_features;
        u32 max_vp_index;
        u32 max_lp_index;
        u8 vtl;
        union {
                u32 isolation_config_a;
                struct {
                        u32 paravisor_present : 1;
                        u32 reserved_a1 : 31;
                };
        };
        union {
                u32 isolation_config_b;
                struct {
                        u32 cvm_type : 4;
                        u32 reserved_b1 : 1;
                        u32 shared_gpa_boundary_active : 1;
                        u32 shared_gpa_boundary_bits : 6;
                        u32 reserved_b2 : 20;
                };
        };
        u64 shared_gpa_boundary;
        bool msi_ext_dest_id;
        bool confidential_vmbus_available;
};
extern struct ms_hyperv_info ms_hyperv;
extern bool hv_nested;
extern u64 hv_current_partition_id;
extern enum hv_partition_type hv_curr_partition_type;

extern void * __percpu *hyperv_pcpu_input_arg;
extern void * __percpu *hyperv_pcpu_output_arg;

u64 hv_do_hypercall(u64 control, void *inputaddr, void *outputaddr);
u64 hv_do_fast_hypercall8(u16 control, u64 input8);
u64 hv_do_fast_hypercall16(u16 control, u64 input1, u64 input2);

bool hv_isolation_type_snp(void);
bool hv_isolation_type_tdx(void);

/*
 * On architectures where Hyper-V doesn't support AEOI (e.g., ARM64),
 * it doesn't provide a recommendation flag and AEOI must be disabled.
 */
static inline bool hv_recommend_using_aeoi(void)
{
#ifdef HV_DEPRECATING_AEOI_RECOMMENDED
        return !(ms_hyperv.hints & HV_DEPRECATING_AEOI_RECOMMENDED);
#else
        return false;
#endif
}

static inline struct hv_proximity_domain_info hv_numa_node_to_pxm_info(int node)
{
        struct hv_proximity_domain_info pxm_info = {};

        if (node != NUMA_NO_NODE) {
                pxm_info.domain_id = node_to_pxm(node);
                pxm_info.flags.proximity_info_valid = 1;
                pxm_info.flags.proximity_preferred = 1;
        }

        return pxm_info;
}

/* Helper functions that provide a consistent pattern for checking Hyper-V hypercall status. */
static inline int hv_result(u64 status)
{
        return status & HV_HYPERCALL_RESULT_MASK;
}

static inline bool hv_result_success(u64 status)
{
        return hv_result(status) == HV_STATUS_SUCCESS;
}

static inline unsigned int hv_repcomp(u64 status)
{
        /* Bits [43:32] of status have 'Reps completed' data. */
        return (status & HV_HYPERCALL_REP_COMP_MASK) >>
                         HV_HYPERCALL_REP_COMP_OFFSET;
}

/*
 * Rep hypercalls. Callers of this functions are supposed to ensure that
 * rep_count, varhead_size, and rep_start comply with Hyper-V hypercall
 * definition.
 */
static inline u64 hv_do_rep_hypercall_ex(u16 code, u16 rep_count,
                                         u16 varhead_size, u16 rep_start,
                                         void *input, void *output)
{
        u64 control = code;
        u64 status;
        u16 rep_comp;

        control |= (u64)varhead_size << HV_HYPERCALL_VARHEAD_OFFSET;
        control |= (u64)rep_count << HV_HYPERCALL_REP_COMP_OFFSET;
        control |= (u64)rep_start << HV_HYPERCALL_REP_START_OFFSET;

        do {
                status = hv_do_hypercall(control, input, output);
                if (!hv_result_success(status))
                        return status;

                rep_comp = hv_repcomp(status);

                control &= ~HV_HYPERCALL_REP_START_MASK;
                control |= (u64)rep_comp << HV_HYPERCALL_REP_START_OFFSET;

                touch_nmi_watchdog();
        } while (rep_comp < rep_count);

        return status;
}

/* For the typical case where rep_start is 0 */
static inline u64 hv_do_rep_hypercall(u16 code, u16 rep_count, u16 varhead_size,
                                      void *input, void *output)
{
        return hv_do_rep_hypercall_ex(code, rep_count, varhead_size, 0,
                                      input, output);
}

/* Generate the guest OS identifier as described in the Hyper-V TLFS */
static inline u64 hv_generate_guest_id(u64 kernel_version)
{
        u64 guest_id;

        guest_id = (((u64)HV_LINUX_VENDOR_ID) << 48);
        guest_id |= (kernel_version << 16);

        return guest_id;
}

int hv_get_hypervisor_version(union hv_hypervisor_version_info *info);

void hv_setup_vmbus_handler(void (*handler)(void));
void hv_remove_vmbus_handler(void);
void hv_setup_stimer0_handler(void (*handler)(void));
void hv_remove_stimer0_handler(void);

void hv_setup_kexec_handler(void (*handler)(void));
void hv_remove_kexec_handler(void);
void hv_setup_crash_handler(void (*handler)(struct pt_regs *regs));
void hv_remove_crash_handler(void);
void hv_setup_mshv_handler(void (*handler)(void));

#if IS_ENABLED(CONFIG_HYPERV)
/*
 * Hypervisor's notion of virtual processor ID is different from
 * Linux' notion of CPU ID. This information can only be retrieved
 * in the context of the calling CPU. Setup a map for easy access
 * to this information.
 */
extern u32 *hv_vp_index;
extern u32 hv_max_vp_index;

extern u64 (*hv_read_reference_counter)(void);

/* Sentinel value for an uninitialized entry in hv_vp_index array */
#define VP_INVAL        U32_MAX

int __init hv_common_init(void);
void __init hv_get_partition_id(void);
void __init hv_common_free(void);
void __init ms_hyperv_late_init(void);
int hv_common_cpu_init(unsigned int cpu);
int hv_common_cpu_die(unsigned int cpu);
void hv_identify_partition_type(void);

/**
 * hv_cpu_number_to_vp_number() - Map CPU to VP.
 * @cpu_number: CPU number in Linux terms
 *
 * This function returns the mapping between the Linux processor
 * number and the hypervisor's virtual processor number, useful
 * in making hypercalls and such that talk about specific
 * processors.
 *
 * Return: Virtual processor number in Hyper-V terms
 */
static inline int hv_cpu_number_to_vp_number(int cpu_number)
{
        return hv_vp_index[cpu_number];
}

static inline int __cpumask_to_vpset(struct hv_vpset *vpset,
                                    const struct cpumask *cpus,
                                    bool (*func)(int cpu))
{
        int cpu, vcpu, vcpu_bank, vcpu_offset, nr_bank = 1;
        int max_vcpu_bank = hv_max_vp_index / HV_VCPUS_PER_SPARSE_BANK;

        /* vpset.valid_bank_mask can represent up to HV_MAX_SPARSE_VCPU_BANKS banks */
        if (max_vcpu_bank >= HV_MAX_SPARSE_VCPU_BANKS)
                return 0;

        /*
         * Clear all banks up to the maximum possible bank as hv_tlb_flush_ex
         * structs are not cleared between calls, we risk flushing unneeded
         * vCPUs otherwise.
         */
        for (vcpu_bank = 0; vcpu_bank <= max_vcpu_bank; vcpu_bank++)
                vpset->bank_contents[vcpu_bank] = 0;

        /*
         * Some banks may end up being empty but this is acceptable.
         */
        for_each_cpu(cpu, cpus) {
                if (func && func(cpu))
                        continue;
                vcpu = hv_cpu_number_to_vp_number(cpu);
                if (vcpu == VP_INVAL)
                        return -1;
                vcpu_bank = vcpu / HV_VCPUS_PER_SPARSE_BANK;
                vcpu_offset = vcpu % HV_VCPUS_PER_SPARSE_BANK;
                __set_bit(vcpu_offset, (unsigned long *)
                          &vpset->bank_contents[vcpu_bank]);
                if (vcpu_bank >= nr_bank)
                        nr_bank = vcpu_bank + 1;
        }
        vpset->valid_bank_mask = GENMASK_ULL(nr_bank - 1, 0);
        return nr_bank;
}

/*
 * Convert a Linux cpumask into a Hyper-V VPset. In the _skip variant,
 * 'func' is called for each CPU present in cpumask.  If 'func' returns
 * true, that CPU is skipped -- i.e., that CPU from cpumask is *not*
 * added to the Hyper-V VPset. If 'func' is NULL, no CPUs are
 * skipped.
 */
static inline int cpumask_to_vpset(struct hv_vpset *vpset,
                                    const struct cpumask *cpus)
{
        return __cpumask_to_vpset(vpset, cpus, NULL);
}

static inline int cpumask_to_vpset_skip(struct hv_vpset *vpset,
                                    const struct cpumask *cpus,
                                    bool (*func)(int cpu))
{
        return __cpumask_to_vpset(vpset, cpus, func);
}

#define _hv_status_fmt(fmt) "%s: Hyper-V status: %#x = %s: " fmt
#define hv_status_printk(level, status, fmt, ...) \
do { \
        u64 __status = (status); \
        pr_##level(_hv_status_fmt(fmt), __func__, hv_result(__status), \
                   hv_result_to_string(__status), ##__VA_ARGS__); \
} while (0)
#define hv_status_err(status, fmt, ...) \
        hv_status_printk(err, status, fmt, ##__VA_ARGS__)
#define hv_status_debug(status, fmt, ...) \
        hv_status_printk(debug, status, fmt, ##__VA_ARGS__)

const char *hv_result_to_string(u64 hv_status);
int hv_result_to_errno(u64 status);
void hyperv_report_panic(struct pt_regs *regs, long err, bool in_die);
bool hv_is_hyperv_initialized(void);
bool hv_is_hibernation_supported(void);
enum hv_isolation_type hv_get_isolation_type(void);
bool hv_is_isolation_supported(void);
bool hv_isolation_type_snp(void);
u64 hv_ghcb_hypercall(u64 control, void *input, void *output, u32 input_size);
u64 hv_tdx_hypercall(u64 control, u64 param1, u64 param2);
void hv_enable_coco_interrupt(unsigned int cpu, unsigned int vector, bool set);
void hv_para_set_sint_proxy(bool enable);
u64 hv_para_get_synic_register(unsigned int reg);
void hv_para_set_synic_register(unsigned int reg, u64 val);
void hyperv_cleanup(void);
bool hv_query_ext_cap(u64 cap_query);
void hv_setup_dma_ops(struct device *dev, bool coherent);
#else /* CONFIG_HYPERV */
static inline void hv_identify_partition_type(void) {}
static inline bool hv_is_hyperv_initialized(void) { return false; }
static inline bool hv_is_hibernation_supported(void) { return false; }
static inline void hyperv_cleanup(void) {}
static inline void ms_hyperv_late_init(void) {}
static inline bool hv_is_isolation_supported(void) { return false; }
static inline enum hv_isolation_type hv_get_isolation_type(void)
{
        return HV_ISOLATION_TYPE_NONE;
}
#endif /* CONFIG_HYPERV */

#if IS_ENABLED(CONFIG_MSHV_ROOT)
static inline bool hv_root_partition(void)
{
        return hv_curr_partition_type == HV_PARTITION_TYPE_ROOT;
}
static inline bool hv_l1vh_partition(void)
{
        return hv_curr_partition_type == HV_PARTITION_TYPE_L1VH;
}
static inline bool hv_parent_partition(void)
{
        return hv_root_partition() || hv_l1vh_partition();
}

bool hv_result_needs_memory(u64 status);
int hv_deposit_memory_node(int node, u64 partition_id, u64 status);
int hv_call_deposit_pages(int node, u64 partition_id, u32 num_pages);
int hv_call_add_logical_proc(int node, u32 lp_index, u32 acpi_id);
int hv_call_create_vp(int node, u64 partition_id, u32 vp_index, u32 flags);

#else /* CONFIG_MSHV_ROOT */
static inline bool hv_root_partition(void) { return false; }
static inline bool hv_l1vh_partition(void) { return false; }
static inline bool hv_parent_partition(void) { return false; }
static inline bool hv_result_needs_memory(u64 status) { return false; }
static inline int hv_deposit_memory_node(int node, u64 partition_id, u64 status)
{
        return -EOPNOTSUPP;
}
static inline int hv_call_deposit_pages(int node, u64 partition_id, u32 num_pages)
{
        return -EOPNOTSUPP;
}
static inline int hv_call_add_logical_proc(int node, u32 lp_index, u32 acpi_id)
{
        return -EOPNOTSUPP;
}
static inline int hv_call_create_vp(int node, u64 partition_id, u32 vp_index, u32 flags)
{
        return -EOPNOTSUPP;
}
#endif /* CONFIG_MSHV_ROOT */

static inline int hv_deposit_memory(u64 partition_id, u64 status)
{
        return hv_deposit_memory_node(NUMA_NO_NODE, partition_id, status);
}

#if IS_ENABLED(CONFIG_HYPERV_VTL_MODE)
u8 __init get_vtl(void);
#else
static inline u8 get_vtl(void) { return 0; }
#endif

#endif