diff options
author | Russell King <rmk@dyn-67.arm.linux.org.uk> | 2008-05-09 23:24:09 +0100 |
---|---|---|
committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2008-05-09 23:24:09 +0100 |
commit | 1f2ee6496b1f71e9d5aa2448745e65fbafdc3bd5 (patch) | |
tree | 3f143311afca5e316afd06c2fc4f7d73b19cdcf0 /kernel/futex.c | |
parent | 5bf6c6e30d8b71d092e8830208e182d84b907fcd (diff) | |
parent | da109897a142dd017172c0ce7abf0be8646f7109 (diff) |
Merge branch 'for-rmk' of git://git.kernel.org/pub/scm/linux/kernel/git/nico/orion into fixes
Diffstat (limited to 'kernel/futex.c')
-rw-r--r-- | kernel/futex.c | 176 |
1 files changed, 6 insertions, 170 deletions
diff --git a/kernel/futex.c b/kernel/futex.c index 98092c9817f..449def8074f 100644 --- a/kernel/futex.c +++ b/kernel/futex.c @@ -104,10 +104,6 @@ struct futex_q { /* Key which the futex is hashed on: */ union futex_key key; - /* For fd, sigio sent using these: */ - int fd; - struct file *filp; - /* Optional priority inheritance state: */ struct futex_pi_state *pi_state; struct task_struct *task; @@ -126,9 +122,6 @@ struct futex_hash_bucket { static struct futex_hash_bucket futex_queues[1<<FUTEX_HASHBITS]; -/* Futex-fs vfsmount entry: */ -static struct vfsmount *futex_mnt; - /* * Take mm->mmap_sem, when futex is shared */ @@ -610,8 +603,6 @@ lookup_pi_state(u32 uval, struct futex_hash_bucket *hb, static void wake_futex(struct futex_q *q) { plist_del(&q->list, &q->list.plist); - if (q->filp) - send_sigio(&q->filp->f_owner, q->fd, POLL_IN); /* * The lock in wake_up_all() is a crucial memory barrier after the * plist_del() and also before assigning to q->lock_ptr. @@ -988,14 +979,10 @@ out: } /* The key must be already stored in q->key. */ -static inline struct futex_hash_bucket * -queue_lock(struct futex_q *q, int fd, struct file *filp) +static inline struct futex_hash_bucket *queue_lock(struct futex_q *q) { struct futex_hash_bucket *hb; - q->fd = fd; - q->filp = filp; - init_waitqueue_head(&q->waiters); get_futex_key_refs(&q->key); @@ -1006,7 +993,7 @@ queue_lock(struct futex_q *q, int fd, struct file *filp) return hb; } -static inline void __queue_me(struct futex_q *q, struct futex_hash_bucket *hb) +static inline void queue_me(struct futex_q *q, struct futex_hash_bucket *hb) { int prio; @@ -1041,15 +1028,6 @@ queue_unlock(struct futex_q *q, struct futex_hash_bucket *hb) * exactly once. They are called with the hashed spinlock held. */ -/* The key must be already stored in q->key. */ -static void queue_me(struct futex_q *q, int fd, struct file *filp) -{ - struct futex_hash_bucket *hb; - - hb = queue_lock(q, fd, filp); - __queue_me(q, hb); -} - /* Return 1 if we were still queued (ie. 0 means we were woken) */ static int unqueue_me(struct futex_q *q) { @@ -1194,7 +1172,7 @@ static int futex_wait(u32 __user *uaddr, struct rw_semaphore *fshared, if (unlikely(ret != 0)) goto out_release_sem; - hb = queue_lock(&q, -1, NULL); + hb = queue_lock(&q); /* * Access the page AFTER the futex is queued. @@ -1238,7 +1216,7 @@ static int futex_wait(u32 __user *uaddr, struct rw_semaphore *fshared, goto out_unlock_release_sem; /* Only actually queue if *uaddr contained val. */ - __queue_me(&q, hb); + queue_me(&q, hb); /* * Now the futex is queued and we have checked the data, we @@ -1386,7 +1364,7 @@ static int futex_lock_pi(u32 __user *uaddr, struct rw_semaphore *fshared, goto out_release_sem; retry_unlocked: - hb = queue_lock(&q, -1, NULL); + hb = queue_lock(&q); retry_locked: ret = lock_taken = 0; @@ -1499,7 +1477,7 @@ static int futex_lock_pi(u32 __user *uaddr, struct rw_semaphore *fshared, /* * Only actually queue now that the atomic ops are done: */ - __queue_me(&q, hb); + queue_me(&q, hb); /* * Now the futex is queued and we have checked the data, we @@ -1746,121 +1724,6 @@ pi_faulted: return ret; } -static int futex_close(struct inode *inode, struct file *filp) -{ - struct futex_q *q = filp->private_data; - - unqueue_me(q); - kfree(q); - - return 0; -} - -/* This is one-shot: once it's gone off you need a new fd */ -static unsigned int futex_poll(struct file *filp, - struct poll_table_struct *wait) -{ - struct futex_q *q = filp->private_data; - int ret = 0; - - poll_wait(filp, &q->waiters, wait); - - /* - * plist_node_empty() is safe here without any lock. - * q->lock_ptr != 0 is not safe, because of ordering against wakeup. - */ - if (plist_node_empty(&q->list)) - ret = POLLIN | POLLRDNORM; - - return ret; -} - -static const struct file_operations futex_fops = { - .release = futex_close, - .poll = futex_poll, -}; - -/* - * Signal allows caller to avoid the race which would occur if they - * set the sigio stuff up afterwards. - */ -static int futex_fd(u32 __user *uaddr, int signal) -{ - struct futex_q *q; - struct file *filp; - int ret, err; - struct rw_semaphore *fshared; - static unsigned long printk_interval; - - if (printk_timed_ratelimit(&printk_interval, 60 * 60 * 1000)) { - printk(KERN_WARNING "Process `%s' used FUTEX_FD, which " - "will be removed from the kernel in June 2007\n", - current->comm); - } - - ret = -EINVAL; - if (!valid_signal(signal)) - goto out; - - ret = get_unused_fd(); - if (ret < 0) - goto out; - filp = get_empty_filp(); - if (!filp) { - put_unused_fd(ret); - ret = -ENFILE; - goto out; - } - filp->f_op = &futex_fops; - filp->f_path.mnt = mntget(futex_mnt); - filp->f_path.dentry = dget(futex_mnt->mnt_root); - filp->f_mapping = filp->f_path.dentry->d_inode->i_mapping; - - if (signal) { - err = __f_setown(filp, task_pid(current), PIDTYPE_PID, 1); - if (err < 0) { - goto error; - } - filp->f_owner.signum = signal; - } - - q = kmalloc(sizeof(*q), GFP_KERNEL); - if (!q) { - err = -ENOMEM; - goto error; - } - q->pi_state = NULL; - - fshared = ¤t->mm->mmap_sem; - down_read(fshared); - err = get_futex_key(uaddr, fshared, &q->key); - - if (unlikely(err != 0)) { - up_read(fshared); - kfree(q); - goto error; - } - - /* - * queue_me() must be called before releasing mmap_sem, because - * key->shared.inode needs to be referenced while holding it. - */ - filp->private_data = q; - - queue_me(q, ret, filp); - up_read(fshared); - - /* Now we map fd to filp, so userspace can access it */ - fd_install(ret, filp); -out: - return ret; -error: - put_unused_fd(ret); - put_filp(filp); - ret = err; - goto out; -} - /* * Support for robust futexes: the kernel cleans up held futexes at * thread exit time. @@ -2092,10 +1955,6 @@ long do_futex(u32 __user *uaddr, int op, u32 val, ktime_t *timeout, 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) */ - ret = futex_fd(uaddr, val); - break; case FUTEX_REQUEUE: ret = futex_requeue(uaddr, fshared, uaddr2, val, val2, NULL); break; @@ -2156,19 +2015,6 @@ asmlinkage long sys_futex(u32 __user *uaddr, int op, u32 val, return do_futex(uaddr, op, val, tp, uaddr2, val2, val3); } -static int futexfs_get_sb(struct file_system_type *fs_type, - int flags, const char *dev_name, void *data, - struct vfsmount *mnt) -{ - return get_sb_pseudo(fs_type, "futex", NULL, FUTEXFS_SUPER_MAGIC, mnt); -} - -static struct file_system_type futex_fs_type = { - .name = "futexfs", - .get_sb = futexfs_get_sb, - .kill_sb = kill_anon_super, -}; - static int __init futex_init(void) { u32 curval; @@ -2193,16 +2039,6 @@ static int __init futex_init(void) spin_lock_init(&futex_queues[i].lock); } - i = register_filesystem(&futex_fs_type); - if (i) - return i; - - futex_mnt = kern_mount(&futex_fs_type); - if (IS_ERR(futex_mnt)) { - unregister_filesystem(&futex_fs_type); - return PTR_ERR(futex_mnt); - } - return 0; } __initcall(futex_init); |