linux-toradex.git/drivers/char/virtio_console.c, branch v3.2.7

Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux

2011-11-07T03:44:47+00:00

* 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: (230 commits)
  Revert "tracing: Include module.h in define_trace.h"
  irq: don't put module.h into irq.h for tracking irqgen modules.
  bluetooth: macroize two small inlines to avoid module.h
  ip_vs.h: fix implicit use of module_get/module_put from module.h
  nf_conntrack.h: fix up fallout from implicit moduleparam.h presence
  include: replace linux/module.h with "struct module" wherever possible
  include: convert various register fcns to macros to avoid include chaining
  crypto.h: remove unused crypto_tfm_alg_modname() inline
  uwb.h: fix implicit use of asm/page.h for PAGE_SIZE
  pm_runtime.h: explicitly requires notifier.h
  linux/dmaengine.h: fix implicit use of bitmap.h and asm/page.h
  miscdevice.h: fix up implicit use of lists and types
  stop_machine.h: fix implicit use of smp.h for smp_processor_id
  of: fix implicit use of errno.h in include/linux/of.h
  of_platform.h: delete needless include 
  acpi: remove module.h include from platform/aclinux.h
  miscdevice.h: delete unnecessary inclusion of module.h
  device_cgroup.h: delete needless include 
  net: sch_generic remove redundant use of 
  net: inet_timewait_sock doesnt need 
  ...

Fix up trivial conflicts (other header files, and  removal of the ab3550 mfd driver) in
 - drivers/media/dvb/frontends/dibx000_common.c
 - drivers/media/video/{mt9m111.c,ov6650.c}
 - drivers/mfd/ab3550-core.c
 - include/linux/dmaengine.h

virtio: console: wait for first console port for early console output

2011-11-02T01:11:01+00:00

On s390 I have seen some random

"Warning: unable to open an initial console"

boot failure. Turns out that tty_open fails, because the
hvc_alloc was not yet done. In former times this could not happen,
since the probe function automatically called hvc_alloc. With newer
versions (multiport) some host<->guest interaction is required
before hvc_alloc is called. This might be too late, especially if
an initramfs is involved. Lets use a completion if we have
multiport and an early console.

[Amit:
  * Use NULL instead of 0 for pointer comparison
  * Rename 'port_added' to 'early_console_added'
  * Re-format, re-word commit message
  * Rebase patch on top of current queue]

Signed-off-by: Christian Borntraeger 
Signed-off-by: Amit Shah 
Acked-by: Chrstian Borntraeger 
Signed-off-by: Rusty Russell

virtio: console: add port stats for bytes received, sent and discarded

2011-11-02T01:11:01+00:00

This commit adds port-specific stats for the number of bytes received,
sent and discarded.  They're exposed via the debugfs interface.  This
data can be used to check for data loss bugs (or disprove such claims).
It can also be used for accounting, if there's such a need.

The stats remain valid throughout the lifetime of the port.  Unplugging
a port will reset the stats.  The numbers are not reset across port
opens/closes.

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

virtio: console: make discard_port_data() use get_inbuf()

2011-11-02T01:11:00+00:00

discard_port_data() used virtqueue_get_buf() directly instead of using
get_inbuf().  Fix this, so that we get accounting for all received
bytes.  This also simplifies the code a lot.

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

virtio: console: rename variable

2011-11-02T01:11:00+00:00

'ret' is a misnomer in discard_port_data() since we don't return the
value.  Rename it to 'err'.
Signed-off-by: Rusty Russell

virtio: console: make get_inbuf() return port->inbuf if present

2011-11-02T01:11:00+00:00

Instead of pulling in a buffer from the vq each time it's called,
get_inbuf() now checks if the current active buffer, in port->inbuf is
valid.  If it is, just returns a pointer to it.  This ends up
simplifying a lot of code calling get_inbuf() since the check for
port->inbuf being valid was done by all the callers.

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

virtio: console: Fix return type for get_inbuf()

2011-11-02T01:11:00+00:00

get_inbuf() returns void *.  There's no reason to return void pointers
instead of the correct struct port_buffer *.

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

virtio: console: Use wait_event_freezable instead of _interruptible

2011-11-02T01:11:00+00:00

Get ready to support suspend/resume by using the freezable calls so that
blocking read/write syscalls are handled properly across suspend/resume.

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

virtio: console: Ignore port name update request if name already set

2011-11-02T01:10:59+00:00

We don't allow port name changes dynamically for a port.  So any
requests by the host to change the name are ignored.

Before this patch, if the hypervisor sent a port name while we had one
set already, we would leak memory equivalent to the size of the old
name.

This scenario wasn't expected so far, but with the suspend-resume
support, we'll send the VIRTIO_CONSOLE_PORT_READY message after restore,
which can get us into this situation.

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

virtio: console: Fix indentation

2011-11-02T01:10:59+00:00

Convert spaces to tabs and fix indentation for an if statement split
into multiple lines.

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