net: add support for ->poll_mask in proto_ops

The socket file operations still implement ->poll until all protocols are
switched over.

Signed-off-by: Christoph Hellwig <hch@lst.de>
This commit is contained in:
Christoph Hellwig 2018-04-09 15:25:28 +02:00
parent 3cafb37633
commit 1525242310
2 changed files with 44 additions and 5 deletions

View file

@ -147,6 +147,7 @@ struct proto_ops {
int (*getname) (struct socket *sock,
struct sockaddr *addr,
int peer);
__poll_t (*poll_mask) (struct socket *sock, __poll_t events);
__poll_t (*poll) (struct file *file, struct socket *sock,
struct poll_table_struct *wait);
int (*ioctl) (struct socket *sock, unsigned int cmd,

View file

@ -117,8 +117,10 @@ static ssize_t sock_write_iter(struct kiocb *iocb, struct iov_iter *from);
static int sock_mmap(struct file *file, struct vm_area_struct *vma);
static int sock_close(struct inode *inode, struct file *file);
static __poll_t sock_poll(struct file *file,
struct poll_table_struct *wait);
static struct wait_queue_head *sock_get_poll_head(struct file *file,
__poll_t events);
static __poll_t sock_poll_mask(struct file *file, __poll_t);
static __poll_t sock_poll(struct file *file, struct poll_table_struct *wait);
static long sock_ioctl(struct file *file, unsigned int cmd, unsigned long arg);
#ifdef CONFIG_COMPAT
static long compat_sock_ioctl(struct file *file,
@ -141,6 +143,8 @@ static const struct file_operations socket_file_ops = {
.llseek = no_llseek,
.read_iter = sock_read_iter,
.write_iter = sock_write_iter,
.get_poll_head = sock_get_poll_head,
.poll_mask = sock_poll_mask,
.poll = sock_poll,
.unlocked_ioctl = sock_ioctl,
#ifdef CONFIG_COMPAT
@ -1114,14 +1118,48 @@ int sock_create_lite(int family, int type, int protocol, struct socket **res)
}
EXPORT_SYMBOL(sock_create_lite);
static struct wait_queue_head *sock_get_poll_head(struct file *file,
__poll_t events)
{
struct socket *sock = file->private_data;
if (!sock->ops->poll_mask)
return NULL;
sock_poll_busy_loop(sock, events);
return sk_sleep(sock->sk);
}
static __poll_t sock_poll_mask(struct file *file, __poll_t events)
{
struct socket *sock = file->private_data;
/*
* We need to be sure we are in sync with the socket flags modification.
*
* This memory barrier is paired in the wq_has_sleeper.
*/
smp_mb();
/* this socket can poll_ll so tell the system call */
return sock->ops->poll_mask(sock, events) |
(sk_can_busy_loop(sock->sk) ? POLL_BUSY_LOOP : 0);
}
/* No kernel lock held - perfect */
static __poll_t sock_poll(struct file *file, poll_table *wait)
{
struct socket *sock = file->private_data;
__poll_t events = poll_requested_events(wait);
__poll_t events = poll_requested_events(wait), mask = 0;
sock_poll_busy_loop(sock, events);
return sock->ops->poll(file, sock, wait) | sock_poll_busy_flag(sock);
if (sock->ops->poll) {
sock_poll_busy_loop(sock, events);
mask = sock->ops->poll(file, sock, wait);
} else if (sock->ops->poll_mask) {
sock_poll_wait(file, sock_get_poll_head(file, events), wait);
mask = sock->ops->poll_mask(sock, events);
}
return mask | sock_poll_busy_flag(sock);
}
static int sock_mmap(struct file *file, struct vm_area_struct *vma)