/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_FUTEX_TYPES_H
#define _LINUX_FUTEX_TYPES_H

#ifdef CONFIG_FUTEX
#include <linux/compiler_types.h>
#include <linux/mutex_types.h>
#include <linux/types.h>

struct compat_robust_list_head;
struct futex_pi_state;
struct robust_list_head;

/**
 * struct futex_sched_data - Futex related per task data
 * @robust_list:        User space registered robust list pointer
 * @compat_robust_list: User space registered robust list pointer for compat tasks
 * @pi_state_list:      List head for Priority Inheritance (PI) state management
 * @pi_state_cache:     Pointer to cache one PI state object per task
 * @exit_mutex:         Mutex for serializing exit
 * @state:              Futex handling state to handle exit races correctly
 */
struct futex_sched_data {
        struct robust_list_head __user          *robust_list;
#ifdef CONFIG_COMPAT
        struct compat_robust_list_head __user   *compat_robust_list;
#endif
        struct list_head                        pi_state_list;
        struct futex_pi_state                   *pi_state_cache;
        struct mutex                            exit_mutex;
        unsigned int                            state;
};

#ifdef CONFIG_FUTEX_PRIVATE_HASH
/**
 * struct futex_mm_phash - Futex private hash related per MM data
 * @lock:       Mutex to protect the private hash operations
 * @hash:       RCU managed pointer to the private hash
 * @hash_new:   Pointer to a newly allocated private hash
 * @batches:    Batch state for RCU synchronization
 * @rcu:        RCU head for call_rcu()
 * @atomic:     Aggregate value for @hash_ref
 * @ref:        Per CPU reference counter for a private hash
 */
struct futex_mm_phash {
        struct mutex                    lock;
        struct futex_private_hash       __rcu *hash;
        struct futex_private_hash       *hash_new;
        unsigned long                   batches;
        struct rcu_head                 rcu;
        atomic_long_t                   atomic;
        unsigned int                    __percpu *ref;
};
#else  /* CONFIG_FUTEX_ROBUST_UNLOCK */
struct futex_mm_phash { };
#endif /* !CONFIG_FUTEX_ROBUST_UNLOCK */

#ifdef CONFIG_FUTEX_ROBUST_UNLOCK
/**
 * struct futex_unlock_cs_range - Range for the VDSO unlock critical section
 * @start_ip:   The start IP of the robust futex unlock critical section (inclusive)
 * @len:        The length of the robust futex unlock critical section
 * @pop_size32: Pending OP pointer size indicator. 0 == 64-bit, 1 == 32-bit
 */
struct futex_unlock_cs_range {
        unsigned long          start_ip;
        unsigned int           len;
        unsigned int           pop_size32;
};

#define FUTEX_ROBUST_MAX_CS_RANGES      (1 + IS_ENABLED(CONFIG_COMPAT))

/**
 * struct futex_unlock_cs_ranges - Futex unlock VSDO critical sections
 * @cs_ranges:  Array of critical section ranges
 */
struct futex_unlock_cs_ranges {
        struct futex_unlock_cs_range    cs_ranges[FUTEX_ROBUST_MAX_CS_RANGES];
};
#else  /* CONFIG_FUTEX_ROBUST_UNLOCK */
struct futex_unlock_cs_ranges { };
#endif /* !CONFIG_FUTEX_ROBUST_UNLOCK */

/**
 * struct futex_mm_data - Futex related per MM data
 * @phash:      Futex private hash related data
 * @unlock:     Futex unlock VDSO critical sections
 */
struct futex_mm_data {
        struct futex_mm_phash           phash;
        struct futex_unlock_cs_ranges   unlock;
};
#else  /* CONFIG_FUTEX */
struct futex_sched_data { };
struct futex_mm_data { };
#endif /* !CONFIG_FUTEX */

#endif /* _LINUX_FUTEX_TYPES_H */