4 files changed, 43 insertions, 8 deletions

diff --git a/include/linux/futex.h b/include/linux/futex.h
index 1a15f8e237a7..90048fb28a38 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 dfbdfb9836f4..421323e5a2d6 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 0006d64c448e..a6baaec44b8f 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 = &current->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 0a43def6fee7..133d558db452 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))