cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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futex.h (2497B)

      1/* SPDX-License-Identifier: GPL-2.0 */
      2#ifndef _LINUX_FUTEX_H
      3#define _LINUX_FUTEX_H
      4
      5#include <linux/sched.h>
      6#include <linux/ktime.h>
      7
      8#include <uapi/linux/futex.h>
      9
     10struct inode;
     11struct mm_struct;
     12struct task_struct;
     13
     14/*
     15 * Futexes are matched on equal values of this key.
     16 * The key type depends on whether it's a shared or private mapping.
     17 * Don't rearrange members without looking at hash_futex().
     18 *
     19 * offset is aligned to a multiple of sizeof(u32) (== 4) by definition.
     20 * We use the two low order bits of offset to tell what is the kind of key :
     21 *  00 : Private process futex (PTHREAD_PROCESS_PRIVATE)
     22 *       (no reference on an inode or mm)
     23 *  01 : Shared futex (PTHREAD_PROCESS_SHARED)
     24 *	mapped on a file (reference on the underlying inode)
     25 *  10 : Shared futex (PTHREAD_PROCESS_SHARED)
     26 *       (but private mapping on an mm, and reference taken on it)
     27*/
     28
     29#define FUT_OFF_INODE    1 /* We set bit 0 if key has a reference on inode */
     30#define FUT_OFF_MMSHARED 2 /* We set bit 1 if key has a reference on mm */
     31
     32union futex_key {
     33	struct {
     34		u64 i_seq;
     35		unsigned long pgoff;
     36		unsigned int offset;
     37	} shared;
     38	struct {
     39		union {
     40			struct mm_struct *mm;
     41			u64 __tmp;
     42		};
     43		unsigned long address;
     44		unsigned int offset;
     45	} private;
     46	struct {
     47		u64 ptr;
     48		unsigned long word;
     49		unsigned int offset;
     50	} both;
     51};
     52
     53#define FUTEX_KEY_INIT (union futex_key) { .both = { .ptr = 0ULL } }
     54
     55#ifdef CONFIG_FUTEX
     56enum {
     57	FUTEX_STATE_OK,
     58	FUTEX_STATE_EXITING,
     59	FUTEX_STATE_DEAD,
     60};
     61
     62static inline void futex_init_task(struct task_struct *tsk)
     63{
     64	tsk->robust_list = NULL;
     65#ifdef CONFIG_COMPAT
     66	tsk->compat_robust_list = NULL;
     67#endif
     68	INIT_LIST_HEAD(&tsk->pi_state_list);
     69	tsk->pi_state_cache = NULL;
     70	tsk->futex_state = FUTEX_STATE_OK;
     71	mutex_init(&tsk->futex_exit_mutex);
     72}
     73
     74void futex_exit_recursive(struct task_struct *tsk);
     75void futex_exit_release(struct task_struct *tsk);
     76void futex_exec_release(struct task_struct *tsk);
     77
     78long do_futex(u32 __user *uaddr, int op, u32 val, ktime_t *timeout,
     79	      u32 __user *uaddr2, u32 val2, u32 val3);
     80#else
     81static inline void futex_init_task(struct task_struct *tsk) { }
     82static inline void futex_exit_recursive(struct task_struct *tsk) { }
     83static inline void futex_exit_release(struct task_struct *tsk) { }
     84static inline void futex_exec_release(struct task_struct *tsk) { }
     85static inline long do_futex(u32 __user *uaddr, int op, u32 val,
     86			    ktime_t *timeout, u32 __user *uaddr2,
     87			    u32 val2, u32 val3)
     88{
     89	return -EINVAL;
     90}
     91#endif
     92
     93#endif