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(I'm so sorry!) Linux kernel mirror (for testing) git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166/* SPDX-License-Identifier: GPL-2.0 */#ifndef _LINUX_FUTEX_H#define _LINUX_FUTEX_H
#include <linux/sched.h>#include <linux/ktime.h>#include <linux/mm_types.h>
#include <uapi/linux/futex.h>
struct inode;struct task_struct;
/* * Futexes are matched on equal values of this key. * The key type depends on whether it's a shared or private mapping. * Don't rearrange members without looking at hash_futex(). * * offset is aligned to a multiple of sizeof(u32) (== 4) by definition. * We use the two low order bits of offset to tell what is the kind of key : * 00 : Private process futex (PTHREAD_PROCESS_PRIVATE) * (no reference on an inode or mm) * 01 : Shared futex (PTHREAD_PROCESS_SHARED) * mapped on a file (reference on the underlying inode) * 10 : Shared futex (PTHREAD_PROCESS_SHARED) * (but private mapping on an mm)*/
#define FUT_OFF_INODE 1 /* We set bit 0 if shared key identifies an inode */#define FUT_OFF_MMSHARED 2 /* We set bit 1 if shared key identifies an mm */
union futex_key { /* For FUT_OFF_INODE */ struct { u64 i_seq; unsigned long pgoff; unsigned int offset; /* unsigned int node; */ } shared;
/* For FUT_OFF_MMSHARED or private */ struct { union { struct mm_struct *mm; /* for private */ u64 mm_seq; /* for FUT_OFF_MMSHARED */ }; unsigned long address; unsigned int offset; /* unsigned int node; */ } private;
struct { u64 ptr; unsigned long word; unsigned int offset; unsigned int node; /* NOT hashed! */ } both;};
#define FUTEX_KEY_INIT (union futex_key) { .both = { .ptr = 0ULL } }
#ifdef CONFIG_FUTEXenum { FUTEX_STATE_OK, FUTEX_STATE_EXITING, FUTEX_STATE_DEAD,};
static inline void futex_init_task(struct task_struct *tsk){ memset(&tsk->futex, 0, sizeof(tsk->futex)); INIT_LIST_HEAD(&tsk->futex.pi_state_list); tsk->futex.state = FUTEX_STATE_OK; mutex_init(&tsk->futex.exit_mutex);}
void futex_exit_recursive(struct task_struct *tsk);void futex_exit_exec_release(struct task_struct *tsk);void futex_exec_done(struct task_struct *tsk);
long do_futex(u32 __user *uaddr, int op, u32 val, ktime_t *timeout, u32 __user *uaddr2, u32 val2, u32 val3);int futex_hash_prctl(unsigned long arg2, unsigned long arg3, unsigned long arg4);
#ifdef CONFIG_FUTEX_PRIVATE_HASHint futex_hash_allocate_default(void);void futex_hash_free(struct mm_struct *mm);#else /* CONFIG_FUTEX_PRIVATE_HASH */static inline int futex_hash_allocate_default(void) { return 0; }static inline int futex_hash_free(struct mm_struct *mm) { return 0; }#endif /* !CONFIG_FUTEX_PRIVATE_HASH */
#else /* CONFIG_FUTEX */static inline void futex_init_task(struct task_struct *tsk) { }static inline void futex_exit_recursive(struct task_struct *tsk) { }static inline void futex_exit_exec_release(struct task_struct *tsk) { }static inline void futex_exec_done(struct task_struct *tsk) { }static inline long do_futex(u32 __user *uaddr, int op, u32 val, ktime_t *timeout, u32 __user *uaddr2, u32 val2, u32 val3){ return -EINVAL;}static inline int futex_hash_prctl(unsigned long arg2, unsigned long arg3, unsigned long arg4){ return -EINVAL;}static inline int futex_hash_allocate_default(void) { return 0; }static inline int futex_hash_free(struct mm_struct *mm) { return 0; }#endif /* !CONFIG_FUTEX */
#ifdef CONFIG_FUTEX_ROBUST_UNLOCK#include <asm/futex_robust.h>
void futex_reset_cs_ranges(struct futex_mm_data *fd);void __futex_fixup_robust_unlock(struct pt_regs *regs, struct futex_unlock_cs_range *csr);
static inline bool futex_within_robust_unlock(struct pt_regs *regs, struct futex_unlock_cs_range *csr){ unsigned long ip = instruction_pointer(regs);
return ip >= csr->start_ip && ip < csr->start_ip + csr->len;}
static inline void futex_fixup_robust_unlock(struct pt_regs *regs){ struct futex_unlock_cs_range *csr;
/* * Avoid dereferencing current->mm if not returning from interrupt. * current->rseq.event is going to be used subsequently, so bringing the * cache line in is not a big deal. */ if (!current->rseq.event.user_irq) return;
csr = current->mm->futex.unlock.cs_ranges;
/* The loop is optimized out for !COMPAT */ for (int r = 0; r < FUTEX_ROBUST_MAX_CS_RANGES; r++, csr++) { if (unlikely(futex_within_robust_unlock(regs, csr))) { __futex_fixup_robust_unlock(regs, csr); return; } }}
static inline void futex_set_vdso_cs_range(struct futex_mm_data *fd, unsigned int idx, unsigned long start, unsigned long end, bool sz32){ fd->unlock.cs_ranges[idx].start_ip = start; fd->unlock.cs_ranges[idx].len = end - start; fd->unlock.cs_ranges[idx].pop_size32 = sz32;}#else /* CONFIG_FUTEX_ROBUST_UNLOCK */static inline void futex_fixup_robust_unlock(struct pt_regs *regs) { }#endif /* !CONFIG_FUTEX_ROBUST_UNLOCK */
#ifdef CONFIG_FUTEXvoid futex_mm_init(struct mm_struct *mm);#elsestatic inline void futex_mm_init(struct mm_struct *mm) { }#endif /* !CONFIG_FUTEX */
#endif /* _LINUX_FUTEX_H */