[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>
This commit is contained in:
Christoph Hellwig 2005-12-22 21:08:46 -08:00 committed by David S. Miller
parent cbeb321a64
commit ce1d4d3e88

View file

@ -640,92 +640,6 @@ 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)
{
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 @@ static ssize_t sock_sendpage(struct file *file, struct page *page,
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);
}