virtio/console: Wait until the port is ready on splice

Wait if the port is not connected or full on splice
like as write is doing.

Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Acked-by: Amit Shah <amit.shah@redhat.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
This commit is contained in:
Masami Hiramatsu 2012-08-09 21:31:00 +09:00 committed by Rusty Russell
parent ec8fc87015
commit efe75d24a6

View File

@ -724,6 +724,26 @@ static ssize_t port_fops_read(struct file *filp, char __user *ubuf,
return fill_readbuf(port, ubuf, count, true);
}
static int wait_port_writable(struct port *port, bool nonblock)
{
int ret;
if (will_write_block(port)) {
if (nonblock)
return -EAGAIN;
ret = wait_event_freezable(port->waitqueue,
!will_write_block(port));
if (ret < 0)
return ret;
}
/* Port got hot-unplugged. */
if (!port->guest_connected)
return -ENODEV;
return 0;
}
static ssize_t port_fops_write(struct file *filp, const char __user *ubuf,
size_t count, loff_t *offp)
{
@ -740,18 +760,9 @@ static ssize_t port_fops_write(struct file *filp, const char __user *ubuf,
nonblock = filp->f_flags & O_NONBLOCK;
if (will_write_block(port)) {
if (nonblock)
return -EAGAIN;
ret = wait_event_freezable(port->waitqueue,
!will_write_block(port));
if (ret < 0)
return ret;
}
/* Port got hot-unplugged. */
if (!port->guest_connected)
return -ENODEV;
ret = wait_port_writable(port, nonblock);
if (ret < 0)
return ret;
count = min((size_t)(32 * 1024), count);
@ -851,6 +862,10 @@ static ssize_t port_fops_splice_write(struct pipe_inode_info *pipe,
.u.data = &sgl,
};
ret = wait_port_writable(port, filp->f_flags & O_NONBLOCK);
if (ret < 0)
return ret;
sgl.n = 0;
sgl.len = 0;
sgl.sg = kmalloc(sizeof(struct scatterlist) * MAX_SPLICE_PAGES,