Zero writes are a dedicated interface for writing regions of zeroes into
the image file.  If clusters are not yet allocated it is possible to use
an efficient metadata representation which keeps the image file compact
and does not store individual zero bytes.

Implementing this for the QED image format is fairly straightforward.
The only issue is that when a zero write touches an existing cluster we
have to allocate a bounce buffer and perform a regular write.
Signed-off-by: NStefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Per-request attributes like read/write are currently implemented as bool
fields in the QEDAIOCB struct.  This becomes unwiedly as the number of
attributes grows.  For example, the qed_aio_setup() function would have
to take multiple bool arguments and at call sites it would be hard to
distinguish the meaning of each bool.

Instead use a flags field with bitmask constants.  This will be used
when zero write support is added.
Signed-off-by: NStefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Copy-on-Read populates the image file with data read from a backing
image.  In order to avoid bloating the image file when all zeroes are
read we should scan the buffer and perform an optimized zero write
operation.
Signed-off-by: NStefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

The ability to zero regions of an image file is a useful primitive for
higher-level features such as image streaming or zero write detection.

Image formats may support an optimized metadata representation instead
of writing zeroes into the image file.  This allows zero writes to be
potentially faster than regular write operations and also preserve
sparseness of the image file.

The .bdrv_co_write_zeroes() interface should be implemented by block
drivers that wish to provide efficient zeroing.

Note that this operation is different from the discard operation, which
may leave the contents of the region indeterminate.  That means
discarded blocks are not guaranteed to contain zeroes and may contain
junk data instead.
Signed-off-by: NStefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

The qemu-img.c:is_not_zero() function checks if a buffer contains all
zeroes.  This function will come in handy for zero-detection in the
block layer, so clean it up and move it to cutils.c.

Note that the function now returns true if the buffer is all zeroes.
This avoids the double-negatives (i.e. !is_not_zero()) that the old
function can cause in callers.
Signed-off-by: NStefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

The ARM devboard models (vexpress-a9, realview, versatilepb, etc)
were accidentally trying to set one of the arm_sysctl properties
after device init. This has now become a fatal error; set the property
before device init where it should be done instead.
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

* bonzini/qdev-props-for-anthony: (25 commits)
  qdev: remove unused fields from PropertyInfo
  qdev: initialize properties via QOM
  qdev: inline qdev_prop_set into qdev_prop_set_ptr
  qdev: access properties via QOM
  qdev: fix off-by-one
  qdev: let QOM free properties
  qdev: remove parse/print methods for pointer properties
  qdev: make the non-legacy pci address property accept an integer
  qdev: remove parse/print methods for mac properties
  qdev: remove print/parse methods from LostTickPolicy properties
  qdev: remove parse method for string properties
  qdev: allow reusing get/set for legacy property
  qdev: remove direct calls to print/parse
  qom: add property get/set wrappers for links
  qom: fix canonical paths vs. interfaces
  qom: use object_resolve_path_type for links
  qom: add object_resolve_path_type
  qom: fix off-by-one
  qom: add property get/set wrappers for C types
  qom: add QObject-based property get/set wrappers
  ...

* aneesh/for-upstream:
  hw/9pfs: Remove O_NOATIME flag from 9pfs open() calls in readonly mode
  hw/9pfs: Update MAINTAINERS file
  fsdev: Fix parameter parsing for proxy helper
  hw/9pfs: Fix crash when mounting with synthfs
  hw/9pfs: Preserve S_ISGID
  hw/9pfs: Add new security model mapped-file.

* sweil/w32:
  w32: Initialise critical section before starting thread (fix #922131)
  w32: Build windows and console executables

Signed-off-by: Nmalc <av1474@comtv.ru>

This patch was contributed by Bogdan Harjoc. I added some assertions.
Reviewed-by: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NStefan Weil <sw@weilnetz.de>

System emulation executables with SDL are typically windows
executables. Sometimes console executables are more useful,
so create both variants if linker option -mwindows was detected.

v2:
This version uses QEMU_PROGW / QEMU_PROG instead of QEMU_PROG / QEMU_PROGC.
Signed-off-by: NStefan Weil <sw@weilnetz.de>

Reviewed-by: NAnthony Liguori <aliguori@us.ibm.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Similarly, use the object properties also to set the default
values of the qdev properties.  This requires reordering
registration and initialization.
Reviewed-by: NAnthony Liguori <aliguori@us.ibm.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

qdev_prop_set is not needed anymore except for hacks, simplify it and
inline it.
Reviewed-by: NAnthony Liguori <aliguori@us.ibm.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Do not poke anymore in the struct when accessing qdev properties.
Instead, ask the object to set the right value.
Reviewed-by: NAnthony Liguori <aliguori@us.ibm.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Integer properties did not work.
Reviewed-by: NAnthony Liguori <aliguori@us.ibm.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Drop the special free callback.  Instead, register a "regular"
release method in the non-legacy property.
Reviewed-by: NAnthony Liguori <aliguori@us.ibm.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Pointer properties (except for PROP_PTR of course) should not need a
legacy counterpart.  In the future, relative paths will ensure that
QEMU will support the same syntax as now for drives etc..
Reviewed-by: NAnthony Liguori <aliguori@us.ibm.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

PCI addresses are set with qdev_prop_uint32.  Thus we make the QOM
property accept a device and function encoded in an 8-bit integer,
instead of the magic dd.f hex string.
Reviewed-by: NAnthony Liguori <aliguori@us.ibm.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Reviewed-by: NAnthony Liguori <aliguori@us.ibm.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Also generalize the code so that we can have more enum properties
in the future.
Reviewed-by: NAnthony Liguori <aliguori@us.ibm.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

We need the print method to put double quotes, but parsing is not special.
Reviewed-by: NAnthony Liguori <aliguori@us.ibm.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

In some cases, a legacy property does need a special print method
but not a special parse method.  In this case, we can reuse the get/set
from the static (non-legacy) property.

If neither parse nor print is needed, though, do not register the
legacy property at all.  The previous patch ensures that the right
fallback will be used.
Reviewed-by: NAnthony Liguori <aliguori@us.ibm.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

There's no need to call into ->parse and ->print manually.  The
QOM legacy properties do that for us.

Furthermore, in some cases legacy and static properties have exactly
the same behavior, and we could drop the legacy properties right away.
Add an appropriate fallback to prepare for this.
Reviewed-by: NAnthony Liguori <aliguori@us.ibm.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

These can set a link to any object, as long as it is included in
the composition tree.
Reviewed-by: NAnthony Liguori <aliguori@us.ibm.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Reviewed-by: NAnthony Liguori <aliguori@us.ibm.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

This allows to restrict partial matches to objects of the expected
type.  It will let people use bare names to reference drives
even though their name might be the same as a device's (e.g.
-drive id=hd0,if=none,... -device ...,drive=hd0,id=hd0).

As a useful byproduct, this fixes a problem with links of interface
type.  When a link property's type is an interface, the code expects
the implementation object (not the parent object) to be stored in the
variable.  The parent object does not contain the right vtable.
Reviewed-by: NAnthony Liguori <aliguori@us.ibm.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Reviewed-by: NAnthony Liguori <aliguori@us.ibm.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Add wrappers that let you get/set properties using normal C data types.

Reviewed-by: Anthony Liguori <anthony@aliguori@us.ibm.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Move the creation of QmpInputVisitor and QmpOutputVisitor from qmp.c
to qom/object.c, since it's the only practical way to access object
properties.

Keep this isolated such that it's easy to remove.  At some point, we need
to remove all usage of QObject in the tree and replace it with GVariant.
Reviewed-by: NAnthony Liguori <aliguori@us.ibm.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Reviewed-by: NAnthony Liguori <aliguori@us.ibm.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

The interface loop can be performed only on the parent object.  It
does not need to be done on each interface.  Similarly, we can
simplify the code by switching early from the implementation
object to the parent object.
Reviewed-by: NAnthony Liguori <aliguori@us.ibm.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Reviewed-by: NAnthony Liguori <aliguori@us.ibm.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Reviewed-by: NAnthony Liguori <aliguori@us.ibm.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

Tested-by: NAndreas Faerber <afaerber@suse.de>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

KVM APIC and PIC require instance sizes.
Signed-off-by: NJan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>

This was missed due to the fact that it's in the top level and it uses
'struct DeviceInfo' instead of 'DeviceInfo' for some strange reason.
Tested-by: NBenoît Canet <benoit.canet@gmail.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>