diff options
-rw-r--r-- | include/linux/futex.h | 10 | ||||
-rw-r--r-- | include/linux/thread_info.h | 1 | ||||
-rw-r--r-- | kernel/futex.c | 37 | ||||
-rw-r--r-- | kernel/futex_compat.c | 3 |
4 files changed, 43 insertions, 8 deletions
diff --git a/include/linux/futex.h b/include/linux/futex.h index 1a15f8e..90048fb 100644 --- a/include/linux/futex.h +++ b/include/linux/futex.h @@ -21,6 +21,8 @@ union ktime; #define FUTEX_LOCK_PI 6 #define FUTEX_UNLOCK_PI 7 #define FUTEX_TRYLOCK_PI 8 +#define FUTEX_WAIT_BITSET 9 +#define FUTEX_WAKE_BITSET 10 #define FUTEX_PRIVATE_FLAG 128 #define FUTEX_CMD_MASK ~FUTEX_PRIVATE_FLAG @@ -33,6 +35,8 @@ union ktime; #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) +#define FUTEX_WAIT_BITSET_PRIVATE (FUTEX_WAIT_BITS | FUTEX_PRIVATE_FLAG) +#define FUTEX_WAKE_BITSET_PRIVATE (FUTEX_WAKE_BITS | FUTEX_PRIVATE_FLAG) /* * Support for robust futexes: the kernel cleans up held futexes at @@ -111,6 +115,12 @@ struct robust_list_head { */ #define ROBUST_LIST_LIMIT 2048 +/* + * bitset with all bits set for the FUTEX_xxx_BITSET OPs to request a + * match of any bit. + */ +#define FUTEX_BITSET_MATCH_ANY 0xffffffff + #ifdef __KERNEL__ long do_futex(u32 __user *uaddr, int op, u32 val, union ktime *timeout, u32 __user *uaddr2, u32 val2, u32 val3); diff --git a/include/linux/thread_info.h b/include/linux/thread_info.h index dfbdfb98..421323e 100644 --- a/include/linux/thread_info.h +++ b/include/linux/thread_info.h @@ -23,6 +23,7 @@ struct restart_block { u32 *uaddr; u32 val; u32 flags; + u32 bitset; u64 time; } futex; }; diff --git a/kernel/futex.c b/kernel/futex.c index 0006d64..a6baaec 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -109,6 +109,9 @@ struct futex_q { /* Optional priority inheritance state: */ struct futex_pi_state *pi_state; struct task_struct *task; + + /* Bitset for the optional bitmasked wakeup */ + u32 bitset; }; /* @@ -722,7 +725,7 @@ double_lock_hb(struct futex_hash_bucket *hb1, struct futex_hash_bucket *hb2) * to this virtual address: */ static int futex_wake(u32 __user *uaddr, struct rw_semaphore *fshared, - int nr_wake) + int nr_wake, u32 bitset) { struct futex_hash_bucket *hb; struct futex_q *this, *next; @@ -730,6 +733,9 @@ static int futex_wake(u32 __user *uaddr, struct rw_semaphore *fshared, union futex_key key; int ret; + if (!bitset) + return -EINVAL; + futex_lock_mm(fshared); ret = get_futex_key(uaddr, fshared, &key); @@ -746,6 +752,11 @@ static int futex_wake(u32 __user *uaddr, struct rw_semaphore *fshared, ret = -EINVAL; break; } + + /* Check if one of the bits is set in both bitsets */ + if (!(this->bitset & bitset)) + continue; + wake_futex(this); if (++ret >= nr_wake) break; @@ -1156,7 +1167,7 @@ static int fixup_pi_state_owner(u32 __user *uaddr, struct futex_q *q, static long futex_wait_restart(struct restart_block *restart); static int futex_wait(u32 __user *uaddr, struct rw_semaphore *fshared, - u32 val, ktime_t *abs_time) + u32 val, ktime_t *abs_time, u32 bitset) { struct task_struct *curr = current; DECLARE_WAITQUEUE(wait, curr); @@ -1167,7 +1178,11 @@ static int futex_wait(u32 __user *uaddr, struct rw_semaphore *fshared, struct hrtimer_sleeper t; int rem = 0; + if (!bitset) + return -EINVAL; + q.pi_state = NULL; + q.bitset = bitset; retry: futex_lock_mm(fshared); @@ -1295,6 +1310,7 @@ static int futex_wait(u32 __user *uaddr, struct rw_semaphore *fshared, restart->futex.uaddr = (u32 *)uaddr; restart->futex.val = val; restart->futex.time = abs_time->tv64; + restart->futex.bitset = bitset; restart->futex.flags = 0; if (fshared) @@ -1321,7 +1337,8 @@ static long futex_wait_restart(struct restart_block *restart) restart->fn = do_no_restart_syscall; if (restart->futex.flags & FLAGS_SHARED) fshared = ¤t->mm->mmap_sem; - return (long)futex_wait(uaddr, fshared, restart->futex.val, &t); + return (long)futex_wait(uaddr, fshared, restart->futex.val, &t, + restart->futex.bitset); } @@ -1942,7 +1959,8 @@ retry: * PI futexes happens in exit_pi_state(): */ if (!pi && (uval & FUTEX_WAITERS)) - futex_wake(uaddr, &curr->mm->mmap_sem, 1); + futex_wake(uaddr, &curr->mm->mmap_sem, 1, + FUTEX_BITSET_MATCH_ANY); } return 0; } @@ -2042,10 +2060,14 @@ long do_futex(u32 __user *uaddr, int op, u32 val, ktime_t *timeout, switch (cmd) { case FUTEX_WAIT: - ret = futex_wait(uaddr, fshared, val, timeout); + val3 = FUTEX_BITSET_MATCH_ANY; + case FUTEX_WAIT_BITSET: + ret = futex_wait(uaddr, fshared, val, timeout, val3); break; case FUTEX_WAKE: - ret = futex_wake(uaddr, fshared, val); + val3 = FUTEX_BITSET_MATCH_ANY; + case FUTEX_WAKE_BITSET: + ret = futex_wake(uaddr, fshared, val, val3); break; case FUTEX_FD: /* non-zero val means F_SETOWN(getpid()) & F_SETSIG(val) */ @@ -2085,7 +2107,8 @@ asmlinkage long sys_futex(u32 __user *uaddr, int op, u32 val, u32 val2 = 0; int cmd = op & FUTEX_CMD_MASK; - if (utime && (cmd == FUTEX_WAIT || cmd == FUTEX_LOCK_PI)) { + if (utime && (cmd == FUTEX_WAIT || cmd == FUTEX_LOCK_PI || + cmd == FUTEX_WAIT_BITSET)) { if (copy_from_user(&ts, utime, sizeof(ts)) != 0) return -EFAULT; if (!timespec_valid(&ts)) diff --git a/kernel/futex_compat.c b/kernel/futex_compat.c index 0a43def..133d558d 100644 --- a/kernel/futex_compat.c +++ b/kernel/futex_compat.c @@ -167,7 +167,8 @@ asmlinkage long compat_sys_futex(u32 __user *uaddr, int op, u32 val, int val2 = 0; int cmd = op & FUTEX_CMD_MASK; - if (utime && (cmd == FUTEX_WAIT || cmd == FUTEX_LOCK_PI)) { + if (utime && (cmd == FUTEX_WAIT || cmd == FUTEX_LOCK_PI || + cmd == FUTEX_WAIT_BITSET)) { if (get_compat_timespec(&ts, utime)) return -EFAULT; if (!timespec_valid(&ts)) |