linux.git/drivers/char/virtio_console.c, branch v3.7-rc2

virtio: console: fix error handling in init() function

2012-09-28T05:35:13+00:00

If register_virtio_driver() fails, virtio-ports class is not destroyed.
The patch adds error handling of register_virtio_driver().

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Alexey Khoroshilov 
Acked-by: Amit Shah 
Signed-off-by: Rusty Russell

virtio/console: Allocate scatterlist according to the current pipe size

2012-09-28T05:35:12+00:00

Allocate scatterlist according to the current pipe size.
This allows splicing bigger buffer if the pipe size has
been changed by fcntl.

Changes in v2:
 - Just a minor fix for avoiding a confliction with previous patch.

Signed-off-by: Masami Hiramatsu 
Acked-by: Amit Shah 
Signed-off-by: Rusty Russell

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

2012-09-28T05:35:12+00:00

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

Signed-off-by: Masami Hiramatsu 
Acked-by: Amit Shah 
Signed-off-by: Rusty Russell

virtio/console: Add a failback for unstealable pipe buffer

2012-09-28T05:35:12+00:00

Add a failback memcpy path for unstealable pipe buffer.
If buf->ops->steal() fails, virtio-serial tries to
copy the page contents to an allocated page, instead
of just failing splice().

Signed-off-by: Masami Hiramatsu 
Acked-by: Amit Shah 
Signed-off-by: Rusty Russell

virtio/console: Add splice_write support

2012-09-28T05:35:12+00:00

Enable to use splice_write from pipe to virtio-console port.
This steals pages from pipe and directly send it to host.

Note that this may accelerate only the guest to host path.

Changes in v2:
 - Use GFP_KERNEL instead of GFP_ATOMIC in syscall context function.

Signed-off-by: Masami Hiramatsu 
Acked-by: Amit Shah 
Signed-off-by: Rusty Russell

virtio: console: tell host of open ports after resume from s3/s4

2012-05-17T09:14:33+00:00

If a port was open before going into one of the sleep states, the port
can continue normal operation after restore.  However, the host has to
be told that the guest side of the connection is open to restore
pre-suspend state.

This wasn't noticed so far due to a bug in qemu that was fixed recently
(which marked the guest-side connection as always open).

CC: stable@vger.kernel.org   # Only for 3.3

Signed-off-by: Amit Shah 
Signed-off-by: Michael S. Tsirkin

simple_open: automatically convert to simple_open()

2012-04-05T22:25:50+00:00

Many users of debugfs copy the implementation of default_open() when
they want to support a custom read/write function op.  This leads to a
proliferation of the default_open() implementation across the entire
tree.

Now that the common implementation has been consolidated into libfs we
can replace all the users of this function with simple_open().

This replacement was done with the following semantic patch:


@ open @
identifier open_f != simple_open;
identifier i, f;
@@
-int open_f(struct inode *i, struct file *f)
-{
(
-if (i->i_private)
-f->private_data = i->i_private;
|
-f->private_data = i->i_private;
)
-return 0;
-}

@ has_open depends on open @
identifier fops;
identifier open.open_f;
@@
struct file_operations fops = {
...
-.open = open_f,
+.open = simple_open,
...
};


[akpm@linux-foundation.org: checkpatch fixes]
Signed-off-by: Stephen Boyd 
Cc: Greg Kroah-Hartman 
Cc: Al Viro 
Cc: Julia Lawall 
Acked-by: Ingo Molnar 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

virtio: console: Disable callbacks for virtqueues at start of S4 freeze

2012-01-12T05:14:45+00:00

To ensure we don't receive any more interrupts from the host after we
enter the freeze function, disable all vq interrupts.

There wasn't any problem seen due to this in tests, but applying this
patch makes the freeze case more robust.

Signed-off-by: Amit Shah 
Signed-off-by: Rusty Russell

virtio: console: Add freeze and restore handlers to support S4

2012-01-12T05:14:45+00:00

Remove all vqs and associated buffers in the freeze callback which
prepares us to go into hibernation state.  On restore, re-create all the
vqs and populate the input vqs with buffers to get to the pre-hibernate
state.

Note: Any outstanding unconsumed buffers are discarded; which means
there's a possibility of data loss in case the host or the guest didn't
consume any data already present in the vqs.  This can be addressed in a
later patch series, perhaps in virtio common code.

Signed-off-by: Amit Shah 
Signed-off-by: Rusty Russell

virtio: console: Move vq and vq buf removal into separate functions

2012-01-12T05:14:45+00:00

This common code will be shared with the PM freeze function.

Signed-off-by: Amit Shah 
Signed-off-by: Rusty Russell