8 #include <linux/file.h>
110 static int eventfd_release(struct inode *inode, struct file *file)  in eventfd_release()  argument
112 	struct eventfd_ctx *ctx = file->private_data;  in eventfd_release()
119 static unsigned int eventfd_poll(struct file *file, poll_table *wait)  in eventfd_poll()  argument
121 	struct eventfd_ctx *ctx = file->private_data;  in eventfd_poll()
125 	poll_wait(file, &ctx->wqh, wait);  in eventfd_poll()
228 static ssize_t eventfd_read(struct file *file, char __user *buf, size_t count,  in eventfd_read()  argument
231 	struct eventfd_ctx *ctx = file->private_data;  in eventfd_read()
237 	res = eventfd_ctx_read(ctx, file->f_flags & O_NONBLOCK, &cnt);  in eventfd_read()
244 static ssize_t eventfd_write(struct file *file, const char __user *buf, size_t count,  in eventfd_write()  argument
247 	struct eventfd_ctx *ctx = file->private_data;  in eventfd_write()
262 	else if (!(file->f_flags & O_NONBLOCK)) {  in eventfd_write()
300  * eventfd_fget - Acquire a reference of an eventfd file descriptor.
301  * @fd: [in] Eventfd file descriptor.
303  * Returns a pointer to the eventfd file structure in case of success, or the
306  * -EBADF    : Invalid @fd file descriptor.
307  * -EINVAL   : The @fd file descriptor is not an eventfd file.
309 struct file *eventfd_fget(int fd)  in eventfd_fget()
311 	struct file *file;  in eventfd_fget()  local
313 	file = fget(fd);  in eventfd_fget()
314 	if (!file)  in eventfd_fget()
316 	if (file->f_op != &eventfd_fops) {  in eventfd_fget()
317 		fput(file);  in eventfd_fget()
321 	return file;  in eventfd_fget()
327  * @fd: [in] Eventfd file descriptor.
336 	struct file *file;  in eventfd_ctx_fdget()  local
339 	file = eventfd_fget(fd);  in eventfd_ctx_fdget()
340 	if (IS_ERR(file))  in eventfd_ctx_fdget()
341 		return (struct eventfd_ctx *) file;  in eventfd_ctx_fdget()
342 	ctx = eventfd_ctx_get(file->private_data);  in eventfd_ctx_fdget()
343 	fput(file);  in eventfd_ctx_fdget()
351  * @file: [in] Eventfd file pointer.
356  * -EINVAL   : The @fd file descriptor is not an eventfd file.
358 struct eventfd_ctx *eventfd_ctx_fileget(struct file *file)  in eventfd_ctx_fileget()  argument
360 	if (file->f_op != &eventfd_fops)  in eventfd_ctx_fileget()
363 	return eventfd_ctx_get(file->private_data);  in eventfd_ctx_fileget()
368  * eventfd_file_create - Creates an eventfd file pointer.
370  * @flags: Flags for the eventfd file.
372  * This function creates an eventfd file pointer, w/out installing it into
373  * the fd table. This is useful when the eventfd file is used during the
375  * creation. So the eventfd creation is split into the file pointer creation
376  * phase, and the file descriptor installation phase.
377  * In this way races with userspace closing the newly installed file descriptor
379  * Returns an eventfd file pointer, or a proper error pointer.
381 struct file *eventfd_file_create(unsigned int count, int flags)  in eventfd_file_create()
383 	struct file *file;  in eventfd_file_create()  local
402 	file = anon_inode_getfile("[eventfd]", &eventfd_fops, ctx,  in eventfd_file_create()
404 	if (IS_ERR(file))  in eventfd_file_create()
407 	return file;  in eventfd_file_create()
413 	struct file *file;  in SYSCALL_DEFINE2()  local
420 	file = eventfd_file_create(count, flags);  in SYSCALL_DEFINE2()
421 	if (IS_ERR(file)) {  in SYSCALL_DEFINE2()
422 		error = PTR_ERR(file);  in SYSCALL_DEFINE2()
425 	fd_install(fd, file);  in SYSCALL_DEFINE2()