The gthread coroutine backend is broken and does not produce a working
QEMU; it is only useful for some very limited debugging situations.
Clean up the backend selection logic in configure so that it now runs
"if on windows use windows; else prefer ucontext; else sigaltstack".

To do this we refactor the configure code to separate out "test
whether we have a working ucontext", "pick a default if user didn't
specify" and "validate that user didn't specify something invalid",
rather than having all three of these run together. We also simplify
the Makefile logic so it just links in the backend the configure
script selects.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 1365419487-19867-3-git-send-email-peter.maydell@linaro.org
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

Provide a convenience function for reporting an error and exiting,
and update various places in the configure script to use it.
This allows us to be a little more consistent about how format
our error messages and makes the calling code shorter.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
Message-id: 1365419487-19867-2-git-send-email-peter.maydell@linaro.org
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

I misread the glib manual, g_source_remove does not let you re-attach
the source later.  This behavior (called "blocking" the source in glib)
is present in glib's source code, but private and not available outside
glib; hence, we have to resort to re-creating the source every time.

In fact, g_source_remove and g_source_destroy are the same thing,
except g_source_destroy is O(1) while g_source_remove scans a potentially
very long list of GSources in the current main loop.  Ugh.  Better
use g_source_destroy explicitly, and leave "tags" to those dummies who
cannot track their pointers' lifetimes.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Message-id: 1365426195-12596-1-git-send-email-pbonzini@redhat.com
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

# By Laszlo Ersek (2) and others
# Via Michael Roth
* mdroth/qga-pull-4-2-13:
  qemu-ga: ga_get_fd_handle(): abort if fd_counter overflows
  qga schema: document generic QERR_UNSUPPORTED
  qga schema: mark optional GuestLogicalProcessor.can-offline with #optional
  qga: add windows implementation for guest-set-time
  qga: add windows implementation for guest-get-time

# By Gerd Hoffmann (7) and Hans de Goede (3)
# Via Gerd Hoffmann
* kraxel/usb.79:
  usb-tablet: Don't claim wakeup capability for USB-2 version
  usb: update docs for bus name change
  usb-hub: report status changes only once
  usb-hub: limit chain length
  xhci: zap unused name field
  xhci: remove unimplemented printfs
  xhci: remove leftover debug printf
  xhci: fix numintrs sanity checks
  usb-redir: Add flow control support
  usb-redir: Fix crash on migration with no client connected

* 'arm-devs.next' of git://git.linaro.org/people/pmaydell/qemu-arm:
  hw/nand.c: Fix nand erase operation
  cadence_uart: Flush queued characters on reset
  pl330: Don't inhibit ES bits on INTEN
  pflash_cfi01: Implement migration support
  pflash_cfi01: Drop unused 'bypass' field
  hw/arm_gic_common: Use vmstate struct rather than save/load functions
  arm_gic: Fix sizes of state fields in preparation for vmstate support
  vmstate: Add support for two dimensional arrays
  hw/onenand.c: fix migration of dynamically allocated buffer "otp"
  hw/sd.c: fix migration of dynamically allocated buffer "buf"
  vmstate.h: introduce VMSTATE_BUFFER_POINTER_UNSAFE macro
  hw/arm_mptimer: Save the timer state
  pl050: Don't send always-constant is_mouse field
  hw/arm/nseries: don't print to stdout or stderr

The char-flow refactoring introduced a busy-wait that depended on
an action from the VCPU thread.  However, the VCPU thread could
never take that action because the busy-wait starved the VCPU thread
of the BQL because it never dropped the mutex while running select.

Paolo doesn't want to drop this optimization for fear that we will
stop detecting these busy waits.  I'm afraid to keep this optimization
even with the busy-wait fixed because I think a similar problem can
occur just with heavy I/O thread load manifesting itself as VCPU pauses.

As a compromise, introduce an artificial timeout after a thousand
iterations but print a rate limited warning when this happens.  This
let's us still detect when this condition occurs without it being
a fatal error.
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>
Message-id: 1365169560-11012-1-git-send-email-aliguori@us.ibm.com

The character backend refactoring introduced an undesirable busy wait.
The busy wait happens if can_read returns zero and there is data available
on the character device's file descriptor.  Then, the I/O watch will
fire continuously and, with TCG, the CPU thread will never run.

    1) Char backend asks front end if it can write
    2) Front end says no
    3) poll() finds the char backend's descriptor is available
    4) Goto (1)

What we really want is this (note that step 3 avoids the busy wait):

    1) Char backend asks front end if it can write
    2) Front end says no
    3) poll() goes on without char backend's descriptor
    4) Goto (1) until qemu_chr_accept_input() called

    5) Char backend asks front end if it can write
    6) Front end says yes
    7) poll() finds the char backend's descriptor is available
    8) Backend handler called

After this patch, the IOWatchPoll source and the watch source are
separated.  The IOWatchPoll is simply a hook that runs during the prepare
phase on each main loop iteration.  The hook adds/removes the actual
source depending on the return value from can_read.

A simple reproducer is

    qemu-system-i386 -serial mon:stdio

... followed by banging on the terminal as much as you can. :)  Without
this patch, emulation will hang.
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>
Message-id: 1365177573-11817-1-git-send-email-pbonzini@redhat.com
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

# By Peter Crosthwaite (2) and others
# Via Stefan Hajnoczi
* stefanha/trivial-patches:
  xilinx_zynq: Cleanup ssi_create_slave
  petalogix_ml605_mmu: Cleanup ssi_create_slave()
  target-s390: Fix SRNMT
  linux-user: Don't omit comma for strace of rt_sigaction()
  test-visitor-serialization: Fix some memory leaks

# By Alex Bligh (2) and Felipe Franciosi (2)
# Via Stefano Stabellini
* sstabellini/xen-2013-04-05:
  Allow xen guests to plug disks of 1 TiB or more
  Introduce 64 bit integer write interface to xenstore
  Xen PV backend: Disable use of O_DIRECT by default as it results in crashes.
  Xen PV backend: Move call to bdrv_new from blk_init to blk_connect

# By Stefan Hajnoczi (4) and Kevin Wolf (3)
# Via Kevin Wolf
* kwolf/for-anthony:
  qcow2: Fix L1 write error handling in qcow2_update_snapshot_refcount
  qcow2: Return real error in qcow2_update_snapshot_refcount
  block: clean up I/O throttling wait_time code
  block: drop duplicated slice extension code
  block: keep I/O throttling slice time constant
  block: fix I/O throttling accounting blind spot
  usb-storage: Forward serial number to scsi-disk

It ignored the error code, and at least the 'goto fail' is obvious
nonsense as it creates an endless loop (if the next attempt doesn't
magically succeed) and leaves the in-memory L1 table in big-endian
instead of converting it back.

In error cases, there's no point in writing an updated L1 table, so
skip this part for them.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

This fixes the error message triggered by the following script:

    cat > /tmp/blkdebug.cfg <<EOF
    [inject-error]
    event = "cluster_free"
    errno = "28"
    immediately = "off"
    EOF

    $qemu_img create -f qcow2 test.qcow2 10G
    $qemu_img snapshot -c snap test.qcow2
    $qemu_img snapshot -d snap blkdebug:/tmp/blkdebug.cfg:test.qcow2
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

The wait_time variable is in seconds.  Reflect this in a comment and use
NANOSECONDS_PER_SECOND instead of BLOCK_IO_SLICE_TIME * 10 (which
happens to have the right value).
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Tested-By: NBenoit Canet <benoit@irqsave.net>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

The current slice is extended when an I/O request exceeds the limit.
There is no need to extend the slice every time we check a request.
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Tested-By: NBenoit Canet <benoit@irqsave.net>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

It is not necessary to adjust the slice time at runtime.  We already
extend the current slice in order to carry over accounting into the next
slice.  Changing the actual slice time value introduces oscillations.

The guest may experience large changes in throughput or IOPS from one
moment to the next when slice times are adjusted.
Reported-by: NBenoît Canet <benoit@irqsave.net>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Tested-By: NBenoit Canet <benoit@irqsave.net>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

I/O throttling relies on bdrv_acct_done() which is called when a request
completes.  This leaves a blind spot since we only charge for completed
requests, not submitted requests.

For example, if there is 1 operation remaining in this time slice the
guest could submit 3 operations and they will all be submitted
successfully since they don't actually get accounted for until they
complete.

Originally we probably thought this is okay since the requests will be
accounted when the time slice is extended.  In practice it causes
fluctuations since the guest can exceed its I/O limit and it will be
punished for this later on.

Account for I/O upon submission so that I/O limits are enforced
properly.
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Tested-By: NBenoit Canet <benoit@irqsave.net>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

usb-storage takes care to fetch the USB serial number from -drive
options, but it neglected to pass its own 'serial' property to the
scsi-disk it creates. With this patch, the 'serial' qdev property and
the 'serial' option in -drive behave the same and correctly apply the
serial number on both USB and SCSI level.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Acked-by: NGerd Hoffmann <kraxel@redhat.com>

Usually, nand erase operation has only 2 or 3 address cycles.
We need to mask s->addr to zero unset stale high-order bytes in the nand address
before using it as the erase address.

This fixes the NAND erase operation in Linux.

[PC: Generalised to work for any number of address cycles rather than just 3]
Signed-off-by: NWendy Liang <jliang@xilinx.com>
Signed-off-by: NPeter Crosthwaite <peter.crosthwaite@xilinx.com>
Message-id: 1364967188-26711-1-git-send-email-peter.crosthwaite@xilinx.com
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Reset can be used to empty the rx-fifo. As the fifo full condition is
used to return false from can_receive, queued rx data should be flushed
on reset accordingly.

Cc: Wendy Liang <jliang@xilinx.com>
Cc: Jason Wu <huanyu@xilinx.com>
Signed-off-by: NPeter Crosthwaite <peter.crosthwaite@xilinx.com>
Reported-by: NJason Wu <huanyu@xilinx.com>
Message-id: 494c1e005e225c915d295ddfd75d992ad2dabc3c.1364964526.git.peter.crosthwaite@xilinx.com
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

This if-else logic inhibits setting of the event status (ES) bits
when interrupts are enabled. This is incorrect. ES should be set
regardless on INTEN state. INTEN only inhibits the signalling of
events to PL330 threads, not setting of the ES register.
Signed-off-by: NPeter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

The current xen backend driver implementation uses int64_t variables
to store the size of the corresponding backend disk/file. It also uses
an int64_t variable to store the block size of that image. When writing
the number of sectors (file_size/block_size) to xenstore, however, it
passes these values as 32 bit signed integers. This will cause an
overflow for any disk of 1 TiB or more.

This patch changes the xen backend driver to use a 64 bit integer write
xenstore function.
Signed-off-by: NFelipe Franciosi <felipe@paradoxo.org>
Signed-off-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>

The current implementation of xen_backend only provides 32 bit integer
functions to write to xenstore. This patch adds two functions that
allow writing 64 bit integers (one generic function and another for
the backend only).

This patch also fixes the size of the char arrays used to represent
these integers as strings (originally 32 bytes, however no more than
12 bytes are needed for 32 bit integers and no more than 21 bytes are
needed for 64 bit integers).
Signed-off-by: NFelipe Franciosi <felipe@paradoxo.org>
Signed-off-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>

Due to what is almost certainly a kernel bug, writes with O_DIRECT may
continue to reference the page after the write has been marked as
completed, particularly in the case of TCP retransmit. In other
scenarios, this "merely" risks data corruption on the write, but with
Xen pages from domU are only transiently mapped into dom0's memory,
resulting in kernel panics when they are subsequently accessed.

This brings PV devices in line with emulated devices.  Removing
O_DIRECT is safe as barrier operations are now correctly passed
through.

See:
   http://lists.xen.org/archives/html/xen-devel/2012-12/msg01154.html
for more details.
Signed-off-by: NAlex Bligh <alex@alex.org.uk>
Signed-off-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>

This commit delays the point at which bdrv_new (and hence blk_open
on the underlying device) is called from blk_init to blk_connect.
This ensures that in an inbound live migrate, the block device is
not opened until it has been closed at the other end. This is in
preparation for supporting devices with open/close consistency
without using O_DIRECT. This commit does NOT itself change O_DIRECT
semantics.
Signed-off-by: NAlex Bligh <alex@alex.org.uk>
Signed-off-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>

Add a vmstate to pflash_cfi01, so that it can be live migrated.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 1363717469-30980-3-git-send-email-peter.maydell@linaro.org

For pflash_cfi01 the 'bypass' field is set to zero and never changes,
so remove it (it is a leftover from pflash_cfi02, where bypass is
implemented).
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 1363717469-30980-2-git-send-email-peter.maydell@linaro.org

Update the GIC save/restore to use vmstate rather than hand-rolled
save/load functions.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NIgor Mitsyanko <i.mitsyanko@gmail.com>
Message-id: 1363975375-3166-4-git-send-email-peter.maydell@linaro.org

In preparation for switching to vmstate for migration support, fix
the sizes of various GIC state fields. In particular, we replace all
the bitfields (which VMState can't deal with) with straightforward
uint8_t values which we do bit operations on. (The bitfields made
more sense when NCPU was set differently in different situations,
but we now always model at the architectural limit of 8.)
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NIgor Mitsyanko <i.mitsyanko@gmail.com>
Reviewed-by: NAndreas Färber <afaerber@suse.de>
Message-id: 1363975375-3166-3-git-send-email-peter.maydell@linaro.org

Add support for migrating two dimensional arrays, by defining
a set of new macros VMSTATE_*_2DARRAY paralleling the existing
VMSTATE_*_ARRAY macros. 2D arrays are handled the same for actual
state serialization; the only difference is that the type check
has to change for a 2D array.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NIgor Mitsyanko <i.mitsyanko@gmail.com>
Message-id: 1363975375-3166-2-git-send-email-peter.maydell@linaro.org

VMSTATE_BUFFER_UNSAFE should be used for buffers inlined in device state, not
for buffers allocated dynamically. Change to VMSTATE_BUFFER_POINTER_UNSAFE macro,
which will do migration right.
Signed-off-by: NIgor Mitsyanko <i.mitsyanko@gmail.com>
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 1362923278-4080-4-git-send-email-i.mitsyanko@gmail.com
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

VMSTATE_BUFFER_UNSAFE should be used for buffers inlined in device state, not
for buffers allocated dynamically. Change to VMSTATE_BUFFER_POINTER_UNSAFE macro,
which will do migration right.
Signed-off-by: NIgor Mitsyanko <i.mitsyanko@gmail.com>
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Tested-by: NMichael Walle <michael@walle.cc>
Message-id: 1362923278-4080-3-git-send-email-i.mitsyanko@gmail.com
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Macro could be used to migrate a dynamically allocated buffer of known size.
Signed-off-by: NIgor Mitsyanko <i.mitsyanko@gmail.com>
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 1362923278-4080-2-git-send-email-i.mitsyanko@gmail.com
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Add a missing VMSTATE_TIMER() entry to the arm_mptimer vmstate
description; this omission meant that we would probably hang on reload
when the timer failed to fire.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NPeter Crosthwaite <peter.crosthwaite@xilinx.com>
Message-id: 1363967348-3044-1-git-send-email-peter.maydell@linaro.org

The is_mouse field of the pl050 state structure is constant (it tracks
whether this is a 'pl050_keyboard' or 'pl050_mouse'), so there's
no need to include it in the VMState structure.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Message-id: 1363628480-29306-1-git-send-email-peter.maydell@linaro.org

Remove various bits of printing to stdout or stderr from the
nseries code, replacing it with a qemu log message where there's
an appropriate log category, and just dropping the output for
some of the more debug-like printing.

In particular, this will get rid of the 'mipid_reset' message
you currently get from 'make check'.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: NAndreas Färber <afaerber@suse.de>
Message-id: 1363368565-24546-1-git-send-email-peter.maydell@linaro.org

# By Luiz Capitulino
# Via Luiz Capitulino
* luiz/queue/qmp:
  chardev: drop the Memory chardev driver
  hmp: human-monitor-command: stop using the Memory chardev driver
  Monitor: Make output buffer dynamic
  qstring: add qstring_get_length()

With the recent m25p80 cleanup there is no need to use
ssi_create_slave_no_init() anymore. Just use ssi_create_slave().
Signed-off-by: NPeter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

With the recent m25p80 cleanup there is no need to use
ssi_create_slave_no_init() anymore. Just use ssi_create_slave().
Signed-off-by: NPeter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

Fallthough into abort = oops.

Cc: qemu-trivial@nongnu.org
Cc: Alexander Graf <agraf@suse.de>
Signed-off-by: NRichard Henderson <rth@twiddle.net>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>