[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: Christoph Hellwig <hch@lst.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/socket.c b/net/socket.c
index f40957a..0dde6da 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -640,92 +640,6 @@
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)
-{
- struct sock_iocb *x, siocb;
- struct socket *sock;
- int flags;
-
- if (pos != 0)
- return -ESPIPE;
- if (size==0) /* Match SYS5 behaviour */
- return 0;
-
- if (is_sync_kiocb(iocb))
- x = &siocb;
- else {
- x = kmalloc(sizeof(struct sock_iocb), GFP_KERNEL);
- 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_iov.iov_base = ubuf;
- x->async_iov.iov_len = size;
- flags = !(iocb->ki_filp->f_flags & O_NONBLOCK) ? 0 : MSG_DONTWAIT;
-
- return __sock_recvmsg(iocb, sock, &x->async_msg, size, flags);
-}
-
-
-/*
- * Write data to a socket. We verify that the user area ubuf..ubuf+size-1
- * is readable by the user process.
- */
-
-static ssize_t sock_aio_write(struct kiocb *iocb, const char __user *ubuf,
- size_t size, loff_t pos)
-{
- struct sock_iocb *x, siocb;
- struct socket *sock;
-
- if (pos != 0)
- return -ESPIPE;
- if(size==0) /* Match SYS5 behaviour */
- return 0;
-
- if (is_sync_kiocb(iocb))
- x = &siocb;
- else {
- x = kmalloc(sizeof(struct sock_iocb), GFP_KERNEL);
- 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);
-}
-
static ssize_t sock_sendpage(struct file *file, struct page *page,
int offset, size_t size, loff_t *ppos, int more)
{
@@ -741,53 +655,135 @@
return sock->ops->sendpage(sock, page, offset, size, flags);
}
-static int sock_readv_writev(int type,
- struct file * file, const struct iovec * iov,
- long count, size_t size)
+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;
+ }
+
+ siocb->kiocb = iocb;
+ siocb->async_iov.iov_base = ubuf;
+ siocb->async_iov.iov_len = size;
+
+ 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;
+
+ for (i = 0 ; i < nr_segs ; i++)
+ size += iov[i].iov_len;
+
+ 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 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 (count == 0) /* Match SYS5 behaviour */
+ return 0;
+
+ x = alloc_sock_iocb(iocb, ubuf, count, &siocb);
+ if (!x)
+ return -ENOMEM;
+ return do_sock_read(&x->async_msg, iocb, iocb->ki_filp,
+ &x->async_iov, 1);
+}
+
+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 = file->private_data;
+ size_t size = 0;
+ int i;
+
+ for (i = 0 ; i < nr_segs ; i++)
+ size += iov[i].iov_len;
+
+ 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_sendmsg(iocb, sock, msg, 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;
+ struct kiocb iocb;
+ struct sock_iocb siocb;
+ int ret;
- sock = file->private_data;
+ init_sync_kiocb(&iocb, NULL);
+ iocb.private = &siocb;
- 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);
-
- if (sock->type == SOCK_SEQPACKET)
- msg.msg_flags |= MSG_EOR;
-
- 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);
-}
-
-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);
+ struct sock_iocb siocb, *x;
+
+ 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);
}