Commit graph

25719 commits

Author SHA1 Message Date
Peter Maydell
c31bc98e3b hw/milkymist-softusb: set buffer in softusb_read_{dmem, pmem} error path
Make sure we set the buffer to something in the softusb_read_{dmem,pmem}
error paths, since the caller will use the buffer unconditionally.
(Newer gcc is smart enough to spot this and complain about 'may be
used uninitialized'.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1364496184-11994-1-git-send-email-peter.maydell@linaro.org
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-04-01 09:08:33 -05:00
Peter Maydell
c34e120554 milkymist-softusb: Don't map RAM memory regions in the device itself
Don't map the pmem and dmem RAM memory regions in the milkymist-softusb
device itself. Instead just expose them as sysbus mmio regions which
the device creator can map appropriately. This allows us to drop the
pmem_base and dmem_base properties. Instead of going via
cpu_physical_memory_read/_write when the device wants to access the
RAMs, we just keep a host pointer to the memory and use that.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Andreas Färber <afaerber@suse.de>
Acked-by: Michael Walle <michael@walle.cc>
Message-id: 1363358063-23973-5-git-send-email-peter.maydell@linaro.org
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-04-01 09:08:33 -05:00
Peter Maydell
20cf850c6a milkymist-minimac2: Just expose buffers as a sysbus mmio region
Just expose the register buffers memory as a standard sysbus mmio
region which the creator of the device can map, rather than
providing a qdev property which the creator has to set to the
base address and then doing the mapping in the device's own
init function.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Andreas Färber <afaerber@suse.de>
Acked-by: Michael Walle <michael@walle.cc>
Message-id: 1363358063-23973-4-git-send-email-peter.maydell@linaro.org
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-04-01 09:08:33 -05:00
Peter Maydell
a86f200aeb musicpal: qdevify musicpal-misc
Make musicpal-misc into its own (trivial) qdev device, so we
can get rid of the abuse of sysbus_add_memory().

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Reviewed-by: Andreas Färber <afaerber@suse.de>
Message-id: 1363358063-23973-3-git-send-email-peter.maydell@linaro.org
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-04-01 09:08:33 -05:00
Peter Maydell
4ce5dae88e sysbus: make SysBusDeviceClass::init optional
Make the SysBusDeviceClass::init optional, for devices which
genuinely don't need to do anything here. In particular, simple
devices which can do all their initialization in their
instance_init method don't need either a DeviceClass::realize
or SysBusDeviceClass::init method.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Andreas Färber <afaerber@suse.de>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Message-id: 1363358063-23973-2-git-send-email-peter.maydell@linaro.org
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-04-01 09:08:33 -05:00
Dunrong Huang
5357406415 target-moxie: set do_interrupt to a target-specific helper function
The value of "do_interrupt" member of CPUClass shoule be set to a
target-specific function, or it will lead to a segfault like below:

$ moxie-softmmu/qemu-system-moxie -M moxiesim
Segmentation fault

Cc: Anthony Green <green@moxielogic.com>
Cc: Blue Swirl <blauwirbel@gmail.com>
Cc: Andreas Färber <afaerber@suse.de>
Signed-off-by: Dunrong Huang <huangdr@cloud-times.com>
Signed-of-by: Anthony Green <green@moxielogic.com>
Reviewed-by: Andreas Färber <afaerber@suse.de>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2013-03-31 18:26:31 +00:00
Stefan Weil
5e3a0f418c w32: Fix build with older gcc (unresolved symbol)
The cross i586-mingw32msvc-gcc 4.4.4 from Debian Squeeze does not support
__sync_val_compare_and_swap by default.

Using -march=i686 fixes that and should also result in better code.

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2013-03-30 14:08:07 +00:00
Stefan Weil
e06335b951 target-moxie: Fix pointer-to-integer conversion (MinGW-w64)
The type cast must use tcg_target_long instead of long.
This makes a difference for hosts where sizeof(long) != sizeof(void *).

Cc: Anthony Green <green@moxielogic.com>
Cc: Blue Swirl <blauwirbel@gmail.com>
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Signed-off-by: Anthony Green <green@moxielogic.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
2013-03-30 14:03:42 +00:00
David Woodhouse
c972121512 piix_pci: Fix C99 comments
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Reviewed-by: Andreas Färber <afaerber@suse.de>
Tested-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Message-id: 1361580039-4459-4-git-send-email-dwmw2@infradead.org
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-03-28 12:59:23 -05:00
David Woodhouse
d93a8a435c piix_pci: Use DEVICE() and ISA_BUS()
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Reviewed-by: Andreas Färber <afaerber@suse.de>
Tested-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Message-id: 1361580039-4459-3-git-send-email-dwmw2@infradead.org
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-03-28 12:59:23 -05:00
David Woodhouse
57a0f0c651 piix_pci: Clean up i440FX object handling
Define and use I440FX_PCI_DEVICE() instead of using DO_UPCAST().

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Reviewed-by: Andreas Färber <afaerber@suse.de>
Tested-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Message-id: 1361580039-4459-2-git-send-email-dwmw2@infradead.org
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-03-28 12:59:22 -05:00
Paolo Bonzini
226ecabfbd qemu-bridge-helper: force usage of a very high MAC address for the bridge
Linux uses the lowest enslaved MAC address as the MAC address of
the bridge.  Set MAC address to a high value so that it does not
affect the MAC address of the bridge.

Changing the MAC address of the bridge could cause a few seconds
of network downtime.

Cc: qemu-stable@nongnu.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 1363971468-21154-1-git-send-email-pbonzini@redhat.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-03-28 12:58:52 -05:00
KONRAD Frederic
2900af5969 virtio-balloon: cleanup: remove qdev field.
The qdev field is no longer needed, just drop it.

Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Tested-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Message-id: 1364377755-15508-7-git-send-email-fred.konrad@greensocs.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-03-28 12:57:41 -05:00
KONRAD Frederic
c96caced3f virtio-balloon: cleanup: QOM casts.
As the virtio-balloon-pci is switched to the new API, we can use QOM
casts.

Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Tested-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Message-id: 1364377755-15508-6-git-send-email-fred.konrad@greensocs.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-03-28 12:57:41 -05:00
KONRAD Frederic
5c7d0962f6 virtio-balloon: cleanup: init and exit function.
This remove old init and exit function as they are no longer needed.

Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Tested-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Message-id: 1364377755-15508-5-git-send-email-fred.konrad@greensocs.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-03-28 12:57:41 -05:00
KONRAD Frederic
30bff6a0f1 virtio-balloon-ccw: switch to the new API.
Here the virtio-balloon-ccw is modified for the new API. The device
virtio-balloon-ccw extends virtio-ccw-device as before. It creates and
connects a virtio-balloon during the init. The properties are not modified.

Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Tested-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Message-id: 1364377755-15508-4-git-send-email-fred.konrad@greensocs.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-03-28 12:57:41 -05:00
KONRAD Frederic
e378e88dfc virtio-balloon-pci: switch to the new API.
Here the virtio-balloon-pci is modified for the new API. The device
virtio-balloon-pci extends virtio-pci. It creates and connects a
virtio-balloon during the init. The properties are not changed.

Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Tested-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Message-id: 1364377755-15508-3-git-send-email-fred.konrad@greensocs.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-03-28 12:57:41 -05:00
KONRAD Frederic
1ab461b534 virtio-balloon: add the virtio-balloon device.
Create virtio-balloon which extends virtio-device, so it can be connected on
virtio-bus.

Signed-off-by: KONRAD Frederic <fred.konrad@greensocs.com>
Reviewed-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Tested-by: Cornelia Huck <cornelia.huck@de.ibm.com>
Message-id: 1364377755-15508-2-git-send-email-fred.konrad@greensocs.com
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
2013-03-28 12:57:41 -05:00
Anthony Liguori
fde245ca7e Merge remote-tracking branch 'stefanha/block' into staging
# By Kevin Wolf (22) and Peter Lieven (1)
# Via Stefan Hajnoczi
* stefanha/block: (23 commits)
  block: Fix direct use of protocols as driver for bdrv_open()
  qcow2: Gather clusters in a looping loop
  qcow2: Move cluster gathering to a non-looping loop
  qcow2: Allow requests with multiple l2metas
  qcow2: Use byte granularity in qcow2_alloc_cluster_offset()
  qcow2: Prepare handle_alloc/copied() for byte granularity
  qcow2: handle_copied(): Implement non-zero host_offset
  qcow2: handle_copied(): Get rid of keep_clusters parameter
  qcow2: handle_copied(): Get rid of nb_clusters parameter
  qcow2: Factor out handle_copied()
  qcow2: Clean up handle_alloc()
  qcow2: Finalise interface of handle_alloc()
  qcow2: handle_alloc(): Get rid of keep_clusters parameter
  qcow2: handle_alloc(): Get rid of nb_clusters parameter
  qcow2: Factor out handle_alloc()
  qcow2: Decouple cluster allocation from cluster reuse code
  qcow2: Change handle_dependency to byte granularity
  qcow2: Improve check for overlapping allocations
  qcow2: Handle dependencies earlier
  qcow2: Remove bogus unlock of s->lock
  ...
2013-03-28 12:57:37 -05:00
Anthony Liguori
837df37e88 Merge remote-tracking branch 'stefanha/tracing' into staging
# By Lluís Vilanova (7) and others
# Via Stefan Hajnoczi
* stefanha/tracing:
  vl: add runstate_set tracepoint
  .gitignore: rename trace/generated-tracers.dtrace
  .gitignore: add trace/generated-events.[ch]
  trace: rebuild generated-events.o when configuration changes
  trace: [stderr] Port to generic event information and new control interface
  trace: [simple] Port to generic event information and new control interface
  trace: [default] Port to generic event information and new control interface
  trace: [monitor] Use new event control interface
  trace: Provide a detailed event control interface
  trace: Provide a generic tracing event descriptor
  trace: [tracetool] Explicitly identify public backends
2013-03-28 12:57:32 -05:00
Kazuya Saito
7e8660032c vl: add runstate_set tracepoint
This patch enables us to know RunState transition. It will be userful
for investigation when the trouble occured in special event such like
live migration, shutdown, suspend, and so on.

Signed-off-by: Kazuya Saito <saito.kazuya@jp.fujitsu.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-03-28 14:20:58 +01:00
Stefan Hajnoczi
a46b24fd5d .gitignore: rename trace/generated-tracers.dtrace
For a while the file was called trace/generated-tracers-dtrace.dtrace
but today it's called trace/generated-tracers.dtrace.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-03-28 14:19:57 +01:00
Stefan Hajnoczi
878e63e6c5 .gitignore: add trace/generated-events.[ch]
Don't display autogenerated files in git-status(1).

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-03-28 14:19:57 +01:00
Stefan Hajnoczi
a7373b1f61 trace: rebuild generated-events.o when configuration changes
Make sure to rebuild generated-events.o when ./configure options change.
This prevents linker errors when a stale generated-events.o gets linked
with code compiled against fresh headers.  For example, try building
with ./configure --enable-trace-backend=stderr followed by ./configure
--enable-trace-backend=dtrace.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-03-28 14:19:57 +01:00
Lluís Vilanova
c6f18b9195 trace: [stderr] Port to generic event information and new control interface
Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-03-28 14:19:57 +01:00
Lluís Vilanova
60481e210d trace: [simple] Port to generic event information and new control interface
The backend is forced to dump event numbers using 64 bits, as TraceEventID is
an enum.

Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-03-28 14:19:57 +01:00
Lluís Vilanova
fd068a953c trace: [default] Port to generic event information and new control interface
Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-03-28 14:19:57 +01:00
Lluís Vilanova
ca285c3fca trace: [monitor] Use new event control interface
Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-03-28 14:19:57 +01:00
Lluís Vilanova
b1bae816c4 trace: Provide a detailed event control interface
This interface decouples event obtaining from interaction.

Events can be obtained through three different methods:

* identifier
* name
* simple wildcard pattern

Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-03-28 14:19:57 +01:00
Lluís Vilanova
45be2f5d0d trace: Provide a generic tracing event descriptor
Uses tracetool to generate a backend-independent tracing event description
(struct TraceEvent).

The values for such structure are generated with the non-public "events"
backend ("events-c" frontend).

The generation of the defines to check if an event is statically enabled is also
moved to the "events" backend ("events-h" frontend).

Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-03-28 14:19:57 +01:00
Lluís Vilanova
93fba1618d trace: [tracetool] Explicitly identify public backends
Public backends are those printed by "--list-backends" and thus considered valid
by the configure script.

Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-03-28 14:19:57 +01:00
Kevin Wolf
5d186eb03e block: Fix direct use of protocols as driver for bdrv_open()
bdrv_open_common() implements direct use of protocols by copying the
pre-opened BlockDriverStates to bs using bdrv_swap(). It did however
first set some fields in bs, which end up in file after the swap. When
bdrv_open() destroys file, it appears to be open, and because it isn't,
qemu could segfault while trying to close it.

Reorder the operations to return immediately in such cases so that file
is correctly detected as closed.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-03-28 11:58:40 +01:00
Kevin Wolf
ecdd5333ab qcow2: Gather clusters in a looping loop
Instead of just checking once in exactly this order if there are
dependendies, non-COW clusters and new allocation, this starts looping
around these. This way we can, for example, gather non-COW clusters after
new allocations as long as the host cluster offsets stay contiguous.

Once handle_dependencies() is extended so that COW areas of in-flight
allocations can be overwritten, this allows to continue with gathering
other clusters (we wouldn't be able to do that without this change
because we would have missed a possible second dependency in one of the
next clusters).

This means that in the typical sequential write case, we can combine the
COW overwrite of one cluster with the allocation of the next cluster as
soon as something like Delayed COW gets actually implemented. It is only
by avoiding splitting requests this way that Delayed COW actually starts
improving performance noticably.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-03-28 11:52:44 +01:00
Kevin Wolf
2c3b32d256 qcow2: Move cluster gathering to a non-looping loop
This patch is mainly to separate the indentation change from the
semantic changes. All that really changes here is that everything moves
into a while loop, all 'goto done' become 'break' and at the end of the
loop a new 'break is inserted.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-03-28 11:52:44 +01:00
Kevin Wolf
88c6588c51 qcow2: Allow requests with multiple l2metas
Instead of expecting a single l2meta, have a list of them. This allows
to still have a single I/O request for the guest data, even though
multiple l2meta may be needed in order to describe both a COW overwrite
and a new cluster allocation (typical sequential write case).

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-03-28 11:52:44 +01:00
Kevin Wolf
710c2496d8 qcow2: Use byte granularity in qcow2_alloc_cluster_offset()
This gets rid of the nb_clusters and keep_clusters and the associated
complicated calculations. Just advance the number of bytes that have
been processed and everything is fine.

This patch advances the variables even after the last operation even
though they aren't used any more afterwards to make things look more
uniform. A later patch will turn the whole thing into a loop and then
it actually starts making sense.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-03-28 11:52:44 +01:00
Kevin Wolf
411d62b04b qcow2: Prepare handle_alloc/copied() for byte granularity
This makes handle_alloc() and handle_copied() return byte-granularity
host offsets instead of returning always the cluster start. This is
required so that qcow2_alloc_cluster_offset() can stop aligning
everything to cluster boundaries.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-03-28 11:52:43 +01:00
Kevin Wolf
e62daaf679 qcow2: handle_copied(): Implement non-zero host_offset
Look only for clusters that start at a given physical offset.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-03-28 11:52:43 +01:00
Kevin Wolf
c53ede9f6d qcow2: handle_copied(): Get rid of keep_clusters parameter
Now *bytes is used to return the length of the area that can be written
to without performing an allocation or COW.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-03-28 11:52:43 +01:00
Kevin Wolf
acb0467f8d qcow2: handle_copied(): Get rid of nb_clusters parameter
handle_copied() uses its bytes parameter now to determine how many
clusters it should try to find.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-03-28 11:52:43 +01:00
Kevin Wolf
0af729ec00 qcow2: Factor out handle_copied()
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-03-28 11:52:43 +01:00
Kevin Wolf
83baa9a471 qcow2: Clean up handle_alloc()
Things can be simplified a bit now. No semantic changes.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-03-28 11:52:43 +01:00
Kevin Wolf
c37f4cd71d qcow2: Finalise interface of handle_alloc()
The interface works completely on a byte granularity now and duplicated
parameters are removed.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-03-28 11:52:43 +01:00
Kevin Wolf
3b8e2e260c qcow2: handle_alloc(): Get rid of keep_clusters parameter
handle_alloc() is now called with the offset at which the actual new
allocation starts instead of the offset at which the whole write request
starts, part of which may already be processed.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-03-28 11:52:43 +01:00
Kevin Wolf
f5bc635094 qcow2: handle_alloc(): Get rid of nb_clusters parameter
We already communicate the same information in *bytes.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-03-28 11:52:43 +01:00
Kevin Wolf
10f0ed8b2f qcow2: Factor out handle_alloc()
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-03-28 11:52:43 +01:00
Kevin Wolf
037689d896 qcow2: Decouple cluster allocation from cluster reuse code
This moves some code that prepares the allocation of new clusters to
where the actual allocation happens. This is the minimum required to be
able to move it to a separate function in the next patch.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-03-28 11:52:43 +01:00
Kevin Wolf
65eb2e35c0 qcow2: Change handle_dependency to byte granularity
This is a more precise description of what really constitutes a
dependency. The behaviour doesn't change at this point because the COW
area of the old request is still aligned to cluster boundaries and
therefore an overlap is detected wheneven the requests touch any part of
the same cluster.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-03-28 11:52:43 +01:00
Kevin Wolf
d9d74f4177 qcow2: Improve check for overlapping allocations
The old code detected an overlapping allocation even when the
allocations didn't actually overlap, but were only adjacent.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-03-28 11:52:43 +01:00
Kevin Wolf
17a71e5823 qcow2: Handle dependencies earlier
Handling overlapping allocations isn't just a detail of cluster
allocation. It is rather one of three ways to get the host cluster
offset for a write request:

1. If a request overlaps an in-flight allocations, the cluster offset
   can be taken from there (this is what handle_dependencies will evolve
   into) or the request must just wait until the allocation has
   completed. Accessing the L2 is not valid in this case, it has
   outdated information.

2. Outside overlapping areas, check the clusters that can be written to
   as they are, with no COW involved.

3. If a COW is required, allocate new clusters

Changing the code to reflect this doesn't change the behaviour because
overlaps cannot exist for clusters that are kept in step 2. It does
however make it easier for later patches to work on clusters that belong
to an allocation that is still in flight.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2013-03-28 11:52:42 +01:00