linux.git/drivers/char/virtio_console.c, branch v3.10

Merge tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

2013-05-02T21:14:04+00:00

Pull virtio & lguest updates from Rusty Russell:
 "Lots of virtio work which wasn't quite ready for last merge window.

  Plus I dived into lguest again, reworking the pagetable code so we can
  move the switcher page: our fixmaps sometimes take more than 2MB now..."

Ugh.  Annoying conflicts with the tcm_vhost -> vhost_scsi rename.
Hopefully correctly resolved.

* tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: (57 commits)
  caif_virtio: Remove bouncing email addresses
  lguest: improve code readability in lg_cpu_start.
  virtio-net: fill only rx queues which are being used
  lguest: map Switcher below fixmap.
  lguest: cache last cpu we ran on.
  lguest: map Switcher text whenever we allocate a new pagetable.
  lguest: don't share Switcher PTE pages between guests.
  lguest: expost switcher_pages array (as lg_switcher_pages).
  lguest: extract shadow PTE walking / allocating.
  lguest: make check_gpte et. al return bool.
  lguest: assume Switcher text is a single page.
  lguest: rename switcher_page to switcher_pages.
  lguest: remove RESERVE_MEM constant.
  lguest: check vaddr not pgd for Switcher protection.
  lguest: prepare to make SWITCHER_ADDR a variable.
  virtio: console: replace EMFILE with EBUSY for already-open port
  virtio-scsi: reset virtqueue affinity when doing cpu hotplug
  virtio-scsi: introduce multiqueue support
  virtio-scsi: push vq lock/unlock into virtscsi_vq_done
  virtio-scsi: pass struct virtio_scsi to virtqueue completion function
  ...

virtio: console: replace EMFILE with EBUSY for already-open port

2013-04-15T05:47:39+00:00

Returning EMFILE (process has too many open files) is incorrect to
indicate a port is already open by another process.  Use EBUSY for that.

This does change what we report to userspace, but I believe userspace
can look at it this way: it gets EBUSY, a new error code, instead of
EMFILE.  It's still an error, and that's not changing.

Reported-by: Mateusz Guzik 
Signed-off-by: Amit Shah 
Signed-off-by: Rusty Russell

virtio_console: make local symbols static

2013-04-08T13:30:26+00:00

Those symbols only used within this file, and should be static.

Signed-off-by: Wei Yongjun 
Acked-by: Amit Shah 
Signed-off-by: Rusty Russell

virtio: console: add locking around c_ovq operations

2013-03-30T03:55:46+00:00

When multiple ovq operations are being performed (lots of open/close
operations on virtio_console fds), the __send_control_msg() function can
get confused without locking.

A simple recipe to cause badness is:
* create a QEMU VM with two virtio-serial ports
* in the guest, do
  while true;do echo abc >/dev/vport0p1;done
  while true;do echo edf >/dev/vport0p2;done

In one run, this caused a panic in __send_control_msg().  In another, I
got

   virtio_console virtio0: control-o:id 0 is not a head!

This also results repeated messages similar to these on the host:

  qemu-kvm: virtio-serial-bus: Unexpected port id 478762112 for device virtio-serial-bus.0
  qemu-kvm: virtio-serial-bus: Unexpected port id 478762368 for device virtio-serial-bus.0

Reported-by: FuXiangChun 
Signed-off-by: Amit Shah 
Reviewed-by: Wanlong Gao 
Reviewed-by: Asias He 
Signed-off-by: Rusty Russell 
Cc: stable@kernel.org

virtio: console: rename cvq_lock to c_ivq_lock

2013-03-30T03:53:48+00:00

The cvq_lock was taken for the c_ivq.  Rename the lock to make that
obvious.

We'll also add a lock around the c_ovq in the next commit, so there's no
ambiguity.

Signed-off-by: Amit Shah 
Reviewed-by: Asias He 
Reviewed-by: Wanlong Gao 
Signed-off-by: Rusty Russell 
Cc: stable@kernel.org

virtio_console: use simplified virtqueue accessors.

2013-03-20T05:15:03+00:00

We never add buffers with input and output parts, so use the new accessors.

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

Revert "virtio_console: Initialize guest_connected=true for rproc_serial"

2013-03-18T08:50:46+00:00

This reverts commit 8078db789a92b10ff6e2d713231b5367e014c53b, and
adds a lengthy comment explaining the problem area.

The reverted patch caused opening of ports to fail for rproc_serial.
In probe guest_connected was set to true, but port_fops_open()
fails with -EMFILE if guest_connected already is true.

Signed-off-by: Sjur Brændeland 
Acked-by: Amit Shah 
Signed-off-by: Rusty Russell

Merge tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux

2013-02-26T22:49:12+00:00

Pull virtio updates from Rusty Russell:
 "All trivial, thanks to the stuff which didn't quite make it time"

* tag 'virtio-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux:
  virtio_console: Initialize guest_connected=true for rproc_serial
  virtio: use module_virtio_driver.
  virtio: Add module driver macro for virtio drivers.
  virtio_console: Use virtio device index to generate port name
  virtio: make pci_device_id const
  virtio: make config_ops const
  virtio-mmio: fix wrong comment about register offset
  virtio_console: Let unconnected rproc device receive data.

virtio_console: Initialize guest_connected=true for rproc_serial

2013-02-13T10:27:45+00:00

When rproc_serial is initialized, guest_connected should be set
to true. We can then revert the extra checks introduced in
commit: "virtio_console: Let unconnected rproc device receive data."

Signed-off-by: Sjur Brændeland 
Signed-off-by: Rusty Russell

virtio_console: Use virtio device index to generate port name

2013-02-12T05:56:39+00:00

Use virtio device index for creating unique device port names.
Current index allocation in virtio is based on a monotonically
increasing variable "index". A better handling of this is to
use device index which is allocated by ida.

Signed-off-by: Sjur Brændeland 
Signed-off-by: Rusty Russell