diff options
Diffstat (limited to 'include/linux/rwsem.h')
| -rw-r--r-- | include/linux/rwsem.h | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/include/linux/rwsem.h b/include/linux/rwsem.h index 56707d5ff6add..ab93b6eae6968 100644 --- a/include/linux/rwsem.h +++ b/include/linux/rwsem.h @@ -44,6 +44,12 @@ struct rw_semaphore { #endif }; +/* + * Setting bit 0 of the owner field with other non-zero bits will indicate + * that the rwsem is writer-owned with an unknown owner. + */ +#define RWSEM_OWNER_UNKNOWN ((struct task_struct *)-1L) + extern struct rw_semaphore *rwsem_down_read_failed(struct rw_semaphore *sem); extern struct rw_semaphore *rwsem_down_read_failed_killable(struct rw_semaphore *sem); extern struct rw_semaphore *rwsem_down_write_failed(struct rw_semaphore *sem); |