#include <linux/spinlock.h>
#include <linux/anon_inodes.h>
#include <linux/eventfd.h>
+#include <linux/syscalls.h>
struct eventfd_ctx {
- spinlock_t lock;
wait_queue_head_t wqh;
/*
* Every time that a write(2) is performed on an eventfd, the
if (n < 0)
return -EINVAL;
- spin_lock_irqsave(&ctx->lock, flags);
+ spin_lock_irqsave(&ctx->wqh.lock, flags);
if (ULLONG_MAX - ctx->count < n)
n = (int) (ULLONG_MAX - ctx->count);
ctx->count += n;
if (waitqueue_active(&ctx->wqh))
wake_up_locked(&ctx->wqh);
- spin_unlock_irqrestore(&ctx->lock, flags);
+ spin_unlock_irqrestore(&ctx->wqh.lock, flags);
return n;
}
poll_wait(file, &ctx->wqh, wait);
- spin_lock_irqsave(&ctx->lock, flags);
+ spin_lock_irqsave(&ctx->wqh.lock, flags);
if (ctx->count > 0)
events |= POLLIN;
if (ctx->count == ULLONG_MAX)
events |= POLLERR;
if (ULLONG_MAX - 1 > ctx->count)
events |= POLLOUT;
- spin_unlock_irqrestore(&ctx->lock, flags);
+ spin_unlock_irqrestore(&ctx->wqh.lock, flags);
return events;
}
if (count < sizeof(ucnt))
return -EINVAL;
- spin_lock_irq(&ctx->lock);
+ spin_lock_irq(&ctx->wqh.lock);
res = -EAGAIN;
ucnt = ctx->count;
if (ucnt > 0)
res = -ERESTARTSYS;
break;
}
- spin_unlock_irq(&ctx->lock);
+ spin_unlock_irq(&ctx->wqh.lock);
schedule();
- spin_lock_irq(&ctx->lock);
+ spin_lock_irq(&ctx->wqh.lock);
}
__remove_wait_queue(&ctx->wqh, &wait);
__set_current_state(TASK_RUNNING);
if (waitqueue_active(&ctx->wqh))
wake_up_locked(&ctx->wqh);
}
- spin_unlock_irq(&ctx->lock);
+ spin_unlock_irq(&ctx->wqh.lock);
if (res > 0 && put_user(ucnt, (__u64 __user *) buf))
return -EFAULT;
return -EFAULT;
if (ucnt == ULLONG_MAX)
return -EINVAL;
- spin_lock_irq(&ctx->lock);
+ spin_lock_irq(&ctx->wqh.lock);
res = -EAGAIN;
if (ULLONG_MAX - ctx->count > ucnt)
res = sizeof(ucnt);
res = -ERESTARTSYS;
break;
}
- spin_unlock_irq(&ctx->lock);
+ spin_unlock_irq(&ctx->wqh.lock);
schedule();
- spin_lock_irq(&ctx->lock);
+ spin_lock_irq(&ctx->wqh.lock);
}
__remove_wait_queue(&ctx->wqh, &wait);
__set_current_state(TASK_RUNNING);
if (waitqueue_active(&ctx->wqh))
wake_up_locked(&ctx->wqh);
}
- spin_unlock_irq(&ctx->lock);
+ spin_unlock_irq(&ctx->wqh.lock);
return res;
}
asmlinkage long sys_eventfd(unsigned int count)
{
- int error, fd;
+ int fd;
struct eventfd_ctx *ctx;
- struct file *file;
- struct inode *inode;
ctx = kmalloc(sizeof(*ctx), GFP_KERNEL);
if (!ctx)
return -ENOMEM;
init_waitqueue_head(&ctx->wqh);
- spin_lock_init(&ctx->lock);
ctx->count = count;
/*
* When we call this, the initialization must be complete, since
* anon_inode_getfd() will install the fd.
*/
- error = anon_inode_getfd(&fd, &inode, &file, "[eventfd]",
- &eventfd_fops, ctx);
- if (!error)
- return fd;
-
- kfree(ctx);
- return error;
+ fd = anon_inode_getfd("[eventfd]", &eventfd_fops, ctx);
+ if (fd < 0)
+ kfree(ctx);
+ return fd;
}