diff options
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/futex.h | 29 |
1 files changed, 26 insertions, 3 deletions
diff --git a/include/linux/futex.h b/include/linux/futex.h index 1bd8dfcb037b..899fc7f20edd 100644 --- a/include/linux/futex.h +++ b/include/linux/futex.h @@ -19,6 +19,18 @@ union ktime; #define FUTEX_TRYLOCK_PI 8 #define FUTEX_CMP_REQUEUE_PI 9 +#define FUTEX_PRIVATE_FLAG 128 +#define FUTEX_CMD_MASK ~FUTEX_PRIVATE_FLAG + +#define FUTEX_WAIT_PRIVATE (FUTEX_WAIT | FUTEX_PRIVATE_FLAG) +#define FUTEX_WAKE_PRIVATE (FUTEX_WAKE | FUTEX_PRIVATE_FLAG) +#define FUTEX_REQUEUE_PRIVATE (FUTEX_REQUEUE | FUTEX_PRIVATE_FLAG) +#define FUTEX_CMP_REQUEUE_PRIVATE (FUTEX_CMP_REQUEUE | FUTEX_PRIVATE_FLAG) +#define FUTEX_WAKE_OP_PRIVATE (FUTEX_WAKE_OP | FUTEX_PRIVATE_FLAG) +#define FUTEX_LOCK_PI_PRIVATE (FUTEX_LOCK_PI | FUTEX_PRIVATE_FLAG) +#define FUTEX_UNLOCK_PI_PRIVATE (FUTEX_UNLOCK_PI | FUTEX_PRIVATE_FLAG) +#define FUTEX_TRYLOCK_PI_PRIVATE (FUTEX_TRYLOCK_PI | FUTEX_PRIVATE_FLAG) + /* * Support for robust futexes: the kernel cleans up held futexes at * thread exit time. @@ -114,8 +126,18 @@ handle_futex_death(u32 __user *uaddr, struct task_struct *curr, int pi); * Don't rearrange members without looking at hash_futex(). * * offset is aligned to a multiple of sizeof(u32) (== 4) by definition. - * We set bit 0 to indicate if it's an inode-based key. - */ + * 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, and reference taken on it) +*/ + +#define FUT_OFF_INODE 1 /* We set bit 0 if key has a reference on inode */ +#define FUT_OFF_MMSHARED 2 /* We set bit 1 if key has a reference on mm */ + union futex_key { u32 __user *uaddr; struct { @@ -134,7 +156,8 @@ union futex_key { int offset; } both; }; -int get_futex_key(u32 __user *uaddr, union futex_key *key); +int get_futex_key(u32 __user *uaddr, struct rw_semaphore *shared, + union futex_key *key); void get_futex_key_refs(union futex_key *key); void drop_futex_key_refs(union futex_key *key); |