Commit Graph

20 Commits

Author SHA1 Message Date
Paolo Bonzini a30cf8760f serial: check if backed by a physical serial port at realize time
Right now, s->poll_msl may linger at "0" value for an arbitrarily long
time, until serial_update_msl is called for the first time.  This is
unnecessary, and will lead to the s->poll_msl field being unnecessarily
migrated.

We can call serial_update_msl immediately at realize time (via
serial_reset) and be done with it.  The memory-mapped UART was already
doing that, but not the ISA and PCI variants.

Regarding the delta bits, be consistent with what serial_reset does when
the serial port is not backed by a physical serial port, and always clear
them at reset time.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-09-19 10:50:07 +02:00
Paolo Bonzini 4df7961faa serial: reset state at startup
When a serial port is started, its initial state is all zero.  Make
it consistent with reset state instead.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-09-19 10:50:07 +02:00
Pavel Dovgalyuk 7385b275d9 serial: fixing vmstate for save/restore
Some fields were added to VMState by this patch to preserve correct
loading of the serial port controller state.
Updating FCR value while loading was also modified to disable generating
an interrupt by loadvm.

Signed-off-by: Pavel Dovgalyuk <Pavel.Dovgaluk@ispras.ru>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-09-11 12:20:32 +02:00
Kirill Batuzov f702e62a19 serial: change retry logic to avoid concurrency
Whenever serial_xmit fails to transmit a byte it adds a watch that would
call it again when the "line" becomes ready. This results in a retry
chain:
  serial_xmit -> add_watch -> serial_xmit
Each chain is able to transmit one character, and for every character
passed to serial by the guest driver a new chain is spawned.

The problem lays with the fact that a new chain is spawned even when
there is one already waiting on the watch. So there can be several retry
chains waiting concurrently on one "line". Every chain tries to transmit
current character, so character order is not messed up. But also every
chain increases retry counter (tsr_retry). If there are enough
concurrent chains this counter will hit MAX_XMIT_RETRY value and
the character will be dropped.

To reproduce this bug you need to feed serial output to some program
consuming it slowly enough. A python script from bug #1335444
description is an example of such program.

This commit changes retry logic in the following way to avoid
concurrency: instead of spawning a new chain for each character being
transmitted spawn only one and make it transmit characters until FIFO is
empty.

The change consists of two parts:
 - add a do {} while () loop in serial_xmit (diff is a bit erratic
   for this part, diff -w will show actual change),
 - do not call serial_xmit from serial_ioport_write if there is one
   waiting on the watch already.

This should fix another issue causing bug #1335444.

Signed-off-by: Kirill Batuzov <batuzovk@ispras.ru>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-07-14 16:14:14 +02:00
Roger Pau Monne e02bc6de30 serial: poll the serial console with G_IO_HUP
On FreeBSD polling a master pty while the other end is not connected
with G_IO_OUT only results in an endless wait. This is different from
the Linux behaviour, that returns immediately. In order to demonstrate
this, I have the following example code:

http://xenbits.xen.org/people/royger/test_poll.c

When executed on Linux:

$ ./test_poll
In callback

On FreeBSD instead, the callback never gets called:

$ ./test_poll

So, in order to workaround this, poll the source with G_IO_HUP (which
makes the code behave the same way on both Linux and FreeBSD).

Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
Cc: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Cc: Michael Tokarev <mjt@tls.msk.ru>
Cc: "Andreas Färber" <afaerber@suse.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: xen-devel@lists.xenproject.org
[Add hw/char/cadence_uart.c too. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2014-06-30 15:04:34 +02:00
Juan Quintela d49805aeea savevm: Remove all the unneeded version_minimum_id_old (x86)
After previous Peter patch, they are redundant.  This way we don't
assign them except when needed.  Once there, there were lots of case
where the ".fields" indentation was wrong:

     .fields = (VMStateField []) {
and
     .fields =      (VMStateField []) {

Change all the combinations to:

     .fields = (VMStateField[]){

The biggest problem (appart from aesthetics) was that checkpatch complained
when we copy&pasted the code from one place to another.

Signed-off-by: Juan Quintela <quintela@redhat.com>
Acked-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
2014-06-16 04:55:26 +02:00
Don Slutz dffacd4654 char/serial: Fix emptyness handling
The commit 88c1ee73d3
char/serial: Fix emptyness check

Still causes extra NULL byte(s) to be sent.

So if the fifo is empty, do not send an extra NULL byte.

Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: Don Slutz <dslutz@verizon.com>
Message-id: 1395160174-16006-1-git-send-email-dslutz@verizon.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2014-04-07 14:51:32 +01:00
Peter Crosthwaite 88c1ee73d3 char/serial: Fix emptyness check
This was guarding against a full fifo rather than an empty fifo when
popping. Fix.

Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Reviewed-by: Martin Kletzander <mkletzan@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2014-02-15 16:10:25 +04:00
Anthony Liguori f7ad538e1e Merge remote-tracking branch 'stefanha/block' into staging
# By Alex Bligh (32) and others
# Via Stefan Hajnoczi
* stefanha/block: (42 commits)
  win32-aio: drop win32_aio_flush_cb()
  aio-win32: replace incorrect AioHandler->opaque usage with ->e
  aio / timers: remove dummy_io_handler_flush from tests/test-aio.c
  aio / timers: Remove legacy interface
  aio / timers: Switch entire codebase to the new timer API
  aio / timers: Add scripts/switch-timer-api
  aio / timers: Add test harness for AioContext timers
  aio / timers: convert block_job_sleep_ns and co_sleep_ns to new API
  aio / timers: Convert rtc_clock to be a QEMUClockType
  aio / timers: Remove main_loop_timerlist
  aio / timers: Rearrange timer.h & make legacy functions call non-legacy
  aio / timers: Add qemu_clock_get_ms and qemu_clock_get_ms
  aio / timers: Remove legacy qemu_clock_deadline & qemu_timerlist_deadline
  aio / timers: Remove alarm timers
  aio / timers: Add documentation and new format calls
  aio / timers: Use all timerlists in icount warp calculations
  aio / timers: Introduce new API timer_new and friends
  aio / timers: On timer modification, qemu_notify or aio_notify
  aio / timers: Convert mainloop to use timeout
  aio / timers: Convert aio_poll to use AioContext timers' deadline
  ...

Message-id: 1377202298-22896-1-git-send-email-stefanha@redhat.com
Signed-off-by: Anthony Liguori <anthony@codemonkey.ws>
2013-08-26 09:19:50 -05:00
Alex Bligh bc72ad6754 aio / timers: Switch entire codebase to the new timer API
This is an autogenerated patch using scripts/switch-timer-api.

Switch the entire code base to using the new timer API.

Note this patch may introduce some line length issues.

Signed-off-by: Alex Bligh <alex@alex.org.uk>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-08-22 19:14:24 +02:00
Seiji Aguchi 4a44d85e28 Convert stderr message calling error_get_pretty() to error_report()
Convert stderr messages calling error_get_pretty()
to error_report().

Timestamp is prepended by -msg timstamp option with it.

Per Markus's comment below, A conversion from fprintf() to
error_report() is always an improvement, regardless of
error_get_pretty().

http://marc.info/?l=qemu-devel&m=137513283408601&w=2

But, it is not reasonable to convert them at one time
because fprintf() is used everwhere in qemu.

So, it should be done step by step with avoiding regression.

Signed-off-by: Seiji Aguchi <seiji.aguchi@hds.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
2013-08-20 11:51:59 -04:00
Paolo Bonzini 2c9b15cab1 memory: add owner argument to initialization functions
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-07-04 17:42:44 +02:00
Vladimir Senkov b165b0d8e6 char/serial: fix copy&paste error (fifo8_is_full vs empty)
Copy&paste error in serial.c causes a crash when attempting
to read from UART (if there is no data to be read)

Signed-off-by: Vladimir Senkov <hangup@gmail.com>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2013-06-17 12:57:50 +04:00
Blue Swirl 371a775dc1 Merge branch 'realize-isa.v2' of git://github.com/afaerber/qemu-cpu
* 'realize-isa.v2' of git://github.com/afaerber/qemu-cpu:
  qdev: Drop FROM_QBUS() macro
  isa: QOM'ify ISADevice
  isa: QOM'ify ISABus
  i8259: Convert PICCommonState to use QOM realizefn
  kvm/i8259: QOM'ify some more
  i8259: QOM'ify some more
  i8254: Convert PITCommonState to QOM realizefn
  kvm/i8254: QOM'ify some more
  i8254: QOM'ify some more
  isa: Use realizefn for ISADevice
  cs4231a: QOM'ify some more
  gus: QOM'ify some more
2013-06-15 10:53:44 +00:00
Peter Crosthwaite b5601df762 char/serial: serial_ioport_write: Factor out common code
These three lines are common to both FIFO and regular mode. Just factor
them out to outside the if rather than replicate the same lines inside
both if and else.

Cc: qemu-trivial@nongnu.org

Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Reviewed-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2013-06-11 23:45:44 +04:00
Peter Crosthwaite 8e8638fa87 char/serial: Use generic Fifo8
Use the generic Fifo8 helper provided by QEMU, rather than re-implement
privately.

Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2013-06-11 23:45:44 +04:00
Peter Crosthwaite 7f4f0a227f char/serial: cosmetic fixes.
Some cosmetic fixes to char/serial fixing some checkpatch errors.

Cc: qemu-trivial@nongnu.org

Signed-off-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Reviewed-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2013-06-11 23:45:44 +04:00
Andreas Färber db895a1e6a isa: Use realizefn for ISADevice
Drop ISADeviceClass::init and the resulting no-op initfn and let
children implement their own realizefn. Adapt error handling.
Split off an instance_init where sensible.

Signed-off-by: Andreas Färber <afaerber@suse.de>
2013-06-07 12:14:45 +02:00
Paolo Bonzini dccfcd0e5f sysemu: avoid proliferation of include/ subdirectories
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-04-15 18:19:25 +02:00
Paolo Bonzini 49ab747f66 hw: move target-independent files to subdirectories
This patch tackles all files that are compiled once, moving
them to subdirectories of hw/.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2013-04-08 18:13:12 +02:00