Commit ce1d4d3e authored by Christoph Hellwig's avatar Christoph Hellwig Committed by David S. Miller
Browse files

[NET]: restructure sock_aio_{read,write} / sock_{readv,writev} 



Mid-term I plan to restructure the file_operations so that we don't need
to have all these duplicate aio and vectored versions.  This patch is
a small step in that direction but also a worthwile cleanup on it's own:

(1) introduce a alloc_sock_iocb helper that encapsulates allocating a
    proper sock_iocb
(2) add do_sock_read and do_sock_write helpers for common read/write
    code

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent cbeb321a

net/socket.c

+110 −114
Original line number Diff line number Diff line
@@ -640,154 +640,150 @@ static void sock_aio_dtor(struct kiocb *iocb) 
	kfree(iocb->private);

}



/*

 *	Read data from a socket. ubuf is a user mode pointer. We make sure the user

 *	area ubuf...ubuf+size-1 is writable before asking the protocol.

 */



static ssize_t sock_aio_read(struct kiocb *iocb, char __user *ubuf,

			 size_t size, loff_t pos)

static ssize_t sock_sendpage(struct file *file, struct page *page,

			     int offset, size_t size, loff_t *ppos, int more)

{

	struct sock_iocb *x, siocb;

	struct socket *sock;

	int flags;



	if (pos != 0)

		return -ESPIPE;

	if (size==0)		/* Match SYS5 behaviour */

		return 0;

	sock = file->private_data;



	if (is_sync_kiocb(iocb))

		x = &siocb;

	else {

		x = kmalloc(sizeof(struct sock_iocb), GFP_KERNEL);

		if (!x)

			return -ENOMEM;

	flags = !(file->f_flags & O_NONBLOCK) ? 0 : MSG_DONTWAIT;

	if (more)

		flags |= MSG_MORE;



	return sock->ops->sendpage(sock, page, offset, size, flags);

}



static struct sock_iocb *alloc_sock_iocb(struct kiocb *iocb,

		char __user *ubuf, size_t size, struct sock_iocb *siocb)

{

	if (!is_sync_kiocb(iocb)) {

		siocb = kmalloc(sizeof(*siocb), GFP_KERNEL);

		if (!siocb)

			return NULL;

		iocb->ki_dtor = sock_aio_dtor;

	}

	iocb->private = x;

	x->kiocb = iocb;

	sock = iocb->ki_filp->private_data; 



	x->async_msg.msg_name = NULL;

	x->async_msg.msg_namelen = 0;

	x->async_msg.msg_iov = &x->async_iov;

	x->async_msg.msg_iovlen = 1;

	x->async_msg.msg_control = NULL;

	x->async_msg.msg_controllen = 0;

	x->async_iov.iov_base = ubuf;

	x->async_iov.iov_len = size;

	flags = !(iocb->ki_filp->f_flags & O_NONBLOCK) ? 0 : MSG_DONTWAIT;

	siocb->kiocb = iocb;

	siocb->async_iov.iov_base = ubuf;

	siocb->async_iov.iov_len = size;



	return __sock_recvmsg(iocb, sock, &x->async_msg, size, flags);

	iocb->private = siocb;

	return siocb;

}



static ssize_t do_sock_read(struct msghdr *msg, struct kiocb *iocb,

		struct file *file, struct iovec *iov, unsigned long nr_segs)

{

	struct socket *sock = file->private_data;

	size_t size = 0;

	int i;



/*

 *	Write data to a socket. We verify that the user area ubuf..ubuf+size-1

 *	is readable by the user process.

 */

        for (i = 0 ; i < nr_segs ; i++)

                size += iov[i].iov_len;



static ssize_t sock_aio_write(struct kiocb *iocb, const char __user *ubuf,

			  size_t size, loff_t pos)

	msg->msg_name = NULL;

	msg->msg_namelen = 0;

	msg->msg_control = NULL;

	msg->msg_controllen = 0;

	msg->msg_iov = (struct iovec *) iov;

	msg->msg_iovlen = nr_segs;

	msg->msg_flags = (file->f_flags & O_NONBLOCK) ? MSG_DONTWAIT : 0;



	return __sock_recvmsg(iocb, sock, msg, size, msg->msg_flags);

}



static ssize_t sock_readv(struct file *file, const struct iovec *iov,

			  unsigned long nr_segs, loff_t *ppos)

{

	struct sock_iocb *x, siocb;

	struct socket *sock;

	struct kiocb iocb;

	struct sock_iocb siocb;

	struct msghdr msg;

	int ret;



        init_sync_kiocb(&iocb, NULL);

	iocb.private = &siocb;



	ret = do_sock_read(&msg, &iocb, file, (struct iovec *)iov, nr_segs);

	if (-EIOCBQUEUED == ret)

		ret = wait_on_sync_kiocb(&iocb);

	return ret;

}



static ssize_t sock_aio_read(struct kiocb *iocb, char __user *ubuf,

			 size_t count, loff_t pos)

{

	struct sock_iocb siocb, *x;



	if (pos != 0)

		return -ESPIPE;

	if(size==0)		/* Match SYS5 behaviour */

	if (count == 0)		/* Match SYS5 behaviour */

		return 0;



	if (is_sync_kiocb(iocb))

		x = &siocb;

	else {

		x = kmalloc(sizeof(struct sock_iocb), GFP_KERNEL);

	x = alloc_sock_iocb(iocb, ubuf, count, &siocb);

	if (!x)

		return -ENOMEM;

		iocb->ki_dtor = sock_aio_dtor;

	}

	iocb->private = x;

	x->kiocb = iocb;

	sock = iocb->ki_filp->private_data; 



	x->async_msg.msg_name = NULL;

	x->async_msg.msg_namelen = 0;

	x->async_msg.msg_iov = &x->async_iov;

	x->async_msg.msg_iovlen = 1;

	x->async_msg.msg_control = NULL;

	x->async_msg.msg_controllen = 0;

	x->async_msg.msg_flags = !(iocb->ki_filp->f_flags & O_NONBLOCK) ? 0 : MSG_DONTWAIT;

	if (sock->type == SOCK_SEQPACKET)

		x->async_msg.msg_flags |= MSG_EOR;

	x->async_iov.iov_base = (void __user *)ubuf;

	x->async_iov.iov_len = size;

	

	return __sock_sendmsg(iocb, sock, &x->async_msg, size);

	return do_sock_read(&x->async_msg, iocb, iocb->ki_filp,

			&x->async_iov, 1);

}



static ssize_t sock_sendpage(struct file *file, struct page *page,

			     int offset, size_t size, loff_t *ppos, int more)

static ssize_t do_sock_write(struct msghdr *msg, struct kiocb *iocb,

		struct file *file, struct iovec *iov, unsigned long nr_segs)

{

	struct socket *sock;

	int flags;

	struct socket *sock = file->private_data;

	size_t size = 0;

	int i;



	sock = file->private_data;

        for (i = 0 ; i < nr_segs ; i++)

                size += iov[i].iov_len;



	flags = !(file->f_flags & O_NONBLOCK) ? 0 : MSG_DONTWAIT;

	if (more)

		flags |= MSG_MORE;

	msg->msg_name = NULL;

	msg->msg_namelen = 0;

	msg->msg_control = NULL;

	msg->msg_controllen = 0;

	msg->msg_iov = (struct iovec *) iov;

	msg->msg_iovlen = nr_segs;

	msg->msg_flags = (file->f_flags & O_NONBLOCK) ? MSG_DONTWAIT : 0;

	if (sock->type == SOCK_SEQPACKET)

		msg->msg_flags |= MSG_EOR;



	return sock->ops->sendpage(sock, page, offset, size, flags);

	return __sock_sendmsg(iocb, sock, msg, size);

}



static int sock_readv_writev(int type,

			     struct file * file, const struct iovec * iov,

			     long count, size_t size)

static ssize_t sock_writev(struct file *file, const struct iovec *iov,

			   unsigned long nr_segs, loff_t *ppos)

{

	struct msghdr msg;

	struct socket *sock;



	sock = file->private_data;



	msg.msg_name = NULL;

	msg.msg_namelen = 0;

	msg.msg_control = NULL;

	msg.msg_controllen = 0;

	msg.msg_iov = (struct iovec *) iov;

	msg.msg_iovlen = count;

	msg.msg_flags = (file->f_flags & O_NONBLOCK) ? MSG_DONTWAIT : 0;



	/* read() does a VERIFY_WRITE */

	if (type == VERIFY_WRITE)

		return sock_recvmsg(sock, &msg, size, msg.msg_flags);

	struct kiocb iocb;

	struct sock_iocb siocb;

	int ret;



	if (sock->type == SOCK_SEQPACKET)

		msg.msg_flags |= MSG_EOR;

	init_sync_kiocb(&iocb, NULL);

	iocb.private = &siocb;



	return sock_sendmsg(sock, &msg, size);

	ret = do_sock_write(&msg, &iocb, file, (struct iovec *)iov, nr_segs);

	if (-EIOCBQUEUED == ret)

		ret = wait_on_sync_kiocb(&iocb);

	return ret;

}



static ssize_t sock_readv(struct file *file, const struct iovec *vector,

			  unsigned long count, loff_t *ppos)

static ssize_t sock_aio_write(struct kiocb *iocb, const char __user *ubuf,

			  size_t count, loff_t pos)

{

	size_t tot_len = 0;

	int i;

        for (i = 0 ; i < count ; i++)

                tot_len += vector[i].iov_len;

	return sock_readv_writev(VERIFY_WRITE,

				 file, vector, count, tot_len);

}

	struct sock_iocb siocb, *x;



static ssize_t sock_writev(struct file *file, const struct iovec *vector,

			   unsigned long count, loff_t *ppos)

{

	size_t tot_len = 0;

	int i;

        for (i = 0 ; i < count ; i++)

                tot_len += vector[i].iov_len;

	return sock_readv_writev(VERIFY_READ,

				 file, vector, count, tot_len);

	if (pos != 0)

		return -ESPIPE;

	if (count == 0)		/* Match SYS5 behaviour */

		return 0;



	x = alloc_sock_iocb(iocb, (void __user *)ubuf, count, &siocb);

	if (!x)

		return -ENOMEM;



	return do_sock_write(&x->async_msg, iocb, iocb->ki_filp,

			&x->async_iov, 1);

}

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