[Qemu-devel] [PATCH] Check availability of uuid header / lib

[Qemu-devel] [PATCH] Check availability of uuid header / lib

[Stefan Weil]

The Universally Unique Identifier library will be used
for the new vdi block driver and maybe other parts of QEMU.

Signed-off-by: Stefan Weil <weil@mail.berlios.de>
---
 Makefile        |    1 +
 Makefile.target |    2 ++
 configure       |   21 +++++++++++++++++++++
 3 files changed, 24 insertions(+), 0 deletions(-)

diff --git a/Makefile b/Makefile
index 66c28e5..ffa9c44 100644
--- a/Makefile
+++ b/Makefile
@@ -33,6 +33,7 @@ else
 DOCS=
 endif
 
+LIBS+=$(UUID_LIBS)
 LIBS+=$(PTHREADLIBS)
 LIBS+=$(CLOCKLIBS)
 
diff --git a/Makefile.target b/Makefile.target
index a593503..3b469e0 100644
--- a/Makefile.target
+++ b/Makefile.target
@@ -541,6 +541,8 @@ ifdef CONFIG_BLUEZ
 LIBS += $(CONFIG_BLUEZ_LIBS)
 endif
 
+LIBS += $(UUID_LIBS)
+
 # xen backend driver support
 obj-$(CONFIG_XEN) += xen_machine_pv.o xen_domainbuild.o
 ifeq ($(CONFIG_XEN), yes)
diff --git a/configure b/configure
index 73cc6b1..fc4c5b4 100755
--- a/configure
+++ b/configure
@@ -972,6 +972,22 @@ if $cc $ARCH_CFLAGS -o $TMPE $TMPC > /dev/null 2> /dev/null ; then
 fi
 
 ##########################################
+# uuid_generate() probe, used for vdi block driver
+uuid="no"
+cat > $TMPC << EOF
+#include <uuid/uuid.h>
+int main(void)
+{
+    uuid_t my_uuid;
+    uuid_generate(my_uuid);
+    return 0;
+}
+EOF
+if $cc $ARCH_CFLAGS -o $TMPE $TMPC -luuid >/dev/null 2>&1; then
+   uuid="yes"
+fi
+
+##########################################
 # vde libraries probe
 if test "$vde" = "yes" ; then
   cat > $TMPC << EOF
@@ -1453,6 +1469,7 @@ echo "Install blobs     $blobs"
 echo -e "KVM support       $kvm"
 echo "fdt support       $fdt"
 echo "preadv support    $preadv"
+echo "uuid support      $uuid"
 
 if test $sdl_too_old = "yes"; then
 echo "-> Your SDL version is too old - please upgrade to have SDL support"
@@ -1697,6 +1714,10 @@ fi
 if test "$fnmatch" = "yes" ; then
   echo "#define HAVE_FNMATCH_H 1" >> $config_h
 fi
+if test "$uuid" = "yes" ; then
+  echo "#define HAVE_UUID_H 1" >> $config_h
+  echo "UUID_LIBS=-luuid" >> $config_mak
+fi
 qemu_version=`head $source_path/VERSION`
 echo "VERSION=$qemu_version" >>$config_mak
 echo "#define QEMU_VERSION \"$qemu_version\"" >> $config_h
-- 
1.5.6.5

Re: [Qemu-devel] [PATCH] Check availability of uuid header / lib

[Stefan Weil]

Stefan Weil schrieb:
> The Universally Unique Identifier library will be used
> for the new vdi block driver and maybe other parts of QEMU.
>
> Signed-off-by: Stefan Weil <weil@mail.berlios.de>
> ---
> Makefile | 1 +
> Makefile.target | 2 ++
> configure | 21 +++++++++++++++++++++
> 3 files changed, 24 insertions(+), 0 deletions(-)
...


That patch no longer applies without merge conflicts.

I just noticed that there was a discussion a year ago
when other developers suggested to use libuuid.

We can see the result of that discussion in the current code:
QEMU does not use libuuid, not even functions with the
same interface. Nor does it include a function to generate
a new UUID value.

There were arguments why QEMU would not need
UUID generation in its code. The VDI block driver
needs UUID generation unless we are satisfied with
dummy or zero values.

My personal preference is using libuuid and the functions
included. For systems without libuuid, a minimalistic
implementation could be provided.

Before I send an update of my patch, I'd like to hear
the opinion of others, especially of the QEMU maintainers.

Regards,
Stefan Weil

Re: [Qemu-devel] [PATCH] Check availability of uuid header / lib

[Anthony Liguori]

Stefan Weil wrote:
> That patch no longer applies without merge conflicts.
>
> I just noticed that there was a discussion a year ago
> when other developers suggested to use libuuid.
>
> We can see the result of that discussion in the current code:
> QEMU does not use libuuid, not even functions with the
> same interface. Nor does it include a function to generate
> a new UUID value.
>
> There were arguments why QEMU would not need
> UUID generation in its code. The VDI block driver
> needs UUID generation unless we are satisfied with
> dummy or zero values.
>   

I don't mind linking against libuuid.

However, I think the VDI block driver has to support AIO before it can 
be merged into the tree.

Regards,

Anthony Liguori

Re: [Qemu-devel] [PATCH] Check availability of uuid header / lib

[Stefan Weil]

Anthony Liguori schrieb:
> Stefan Weil wrote:
>> That patch no longer applies without merge conflicts.
>>
>> I just noticed that there was a discussion a year ago
>> when other developers suggested to use libuuid.
>>
>> We can see the result of that discussion in the current code:
>> QEMU does not use libuuid, not even functions with the
>> same interface. Nor does it include a function to generate
>> a new UUID value.
>>
>> There were arguments why QEMU would not need
>> UUID generation in its code. The VDI block driver
>> needs UUID generation unless we are satisfied with
>> dummy or zero values.
>>   
>
> I don't mind linking against libuuid.
>
> However, I think the VDI block driver has to support AIO before it can
> be merged into the tree.
>
> Regards,
>
> Anthony Liguori
>

AIO code is available now. See separate mail.

Regards,

Stefan Weil

[Qemu-devel] [PATCH] RFC: Add new block driver for the VDI format (aio version)

[Stefan Weil]

Stefan Weil schrieb:
> Hello,
>
> this mail will be followed by two patches which
> allow QEMU to create, read and write VDI images.
> VDI is the native image format of SUN's VirtualBox emulator.
>
> The code was written from scratch for QEMU, while earlier patches
> sent to Qemu-devel were wrappers for code from VirtualBox. See
> http://lists.gnu.org/archive/html/qemu-devel/2008-07/msg00366.html
> for those patches.
>
> Patch 1 adds uuid support to QEMU and can be used independent of
> the second patch (look for uuid in vl.c, for example).
>
> Patch 2 adds the VDI block driver. It only needs uuid support
> when a new image is created (without uuid, it will create an image
> with zeroed "uuid" values), so this second patch is semi-independent
> of the first.
>
> Please test, comment and add both patches to QEMU master
> (if there are no objections).
>
> Regards
>
> Stefan Weil


The new version of the VDI block driver adds these changes:

* Fix allocation of new blocks. The old code did not update the image
header,
  so after a new program start, new allocations had overwritten old ones.
  This is something still untested by qemu-iotests.

* Fix endianess issues. I'm sorry I could not test it up to now,
  but it should work nevertheless :-)

* Support asynchronous i/o. The synchronous code is still included as a
  compile time option, but the default is asynchronous, and it works.
  I'm very sure the aio code can be improved, and some parts are
  even unnecessary (at least I think so), so if you are a
  block driver expert: please review the code and send comments.

* Support checking of VDI images. These consistency checks were very
  helpful during driver development!

* Support static images. Static images use pre-allocated blocks
  while dynamic images (default) allocate blocks on demand.


Here is an overview of the new patches:

* Patch 1 adds UUID support to QEMU. This update of the old patch was
  needed because of changes in QEMU's configure / Makefiles.
  Please commit it to QEMU master, so I don't have to fix and resend it
  when there are additional changes in these files.

* Patch 2 is the new VDI block driver. Reviews and suggestions are
  welcome.

* Patch 3 fixes qemu-io-tests to support the new VDI block driver
  (needed because of new option for static images).


The latest code is also available from http://repo.or.cz/w/qemu/ar7.git

Regards

Stefan Weil

[Qemu-devel] [PATCH] Check availability of uuid header / lib

[Stefan Weil]

The Universally Unique Identifier library will be used
for the new vdi block driver and maybe other parts of QEMU.

Signed-off-by: Stefan Weil <weil@mail.berlios.de>
---
 Makefile        |    1 +
 Makefile.target |    2 ++
 configure       |   21 +++++++++++++++++++++
 3 files changed, 24 insertions(+), 0 deletions(-)

diff --git a/Makefile b/Makefile
index dc95869..d8fa730 100644
--- a/Makefile
+++ b/Makefile
@@ -29,6 +29,7 @@ else
 DOCS=
 endif
 
+LIBS+=$(UUID_LIBS)
 LIBS+=$(PTHREADLIBS)
 LIBS+=$(CLOCKLIBS)
 
diff --git a/Makefile.target b/Makefile.target
index f9cd42a..4a01e96 100644
--- a/Makefile.target
+++ b/Makefile.target
@@ -469,6 +469,8 @@ ifdef CONFIG_BLUEZ
 LIBS += $(CONFIG_BLUEZ_LIBS)
 endif
 
+LIBS += $(UUID_LIBS)
+
 # xen backend driver support
 obj-$(CONFIG_XEN) += xen_machine_pv.o xen_domainbuild.o
 ifeq ($(CONFIG_XEN), y)
diff --git a/configure b/configure
index 39bed79..28a9c48 100755
--- a/configure
+++ b/configure
@@ -995,6 +995,22 @@ if $cc $ARCH_CFLAGS -o $TMPE $TMPC > /dev/null 2> /dev/null ; then
 fi
 
 ##########################################
+# uuid_generate() probe, used for vdi block driver
+uuid="no"
+cat > $TMPC << EOF
+#include <uuid/uuid.h>
+int main(void)
+{
+    uuid_t my_uuid;
+    uuid_generate(my_uuid);
+    return 0;
+}
+EOF
+if $cc $ARCH_CFLAGS -o $TMPE $TMPC -luuid >/dev/null 2>&1; then
+   uuid="yes"
+fi
+
+##########################################
 # vde libraries probe
 if test "$vde" = "yes" ; then
   cat > $TMPC << EOF
@@ -1473,6 +1489,7 @@ echo "Install blobs     $blobs"
 echo -e "KVM support       $kvm"
 echo "fdt support       $fdt"
 echo "preadv support    $preadv"
+echo "uuid support      $uuid"
 
 if test $sdl_too_old = "yes"; then
 echo "-> Your SDL version is too old - please upgrade to have SDL support"
@@ -1655,6 +1672,10 @@ fi
 if test "$fnmatch" = "yes" ; then
   echo "#define HAVE_FNMATCH_H 1" >> $config_host_h
 fi
+if test "$uuid" = "yes" ; then
+  echo "#define HAVE_UUID_H 1" >> $config_host_h
+  echo "UUID_LIBS=-luuid" >> $config_host_mak
+fi
 qemu_version=`head $source_path/VERSION`
 echo "VERSION=$qemu_version" >>$config_host_mak
 echo "#define QEMU_VERSION \"$qemu_version\"" >> $config_host_h
-- 
1.5.6.5

Re: [Qemu-devel] [PATCH] Check availability of uuid header / lib

[Christoph Egger]

On Thursday 23 July 2009 22:27:54 Stefan Weil wrote:
> The Universally Unique Identifier library will be used
> for the new vdi block driver and maybe other parts of QEMU.

This is very Linux specific.
On NetBSD, the header is in <sys/uuid.h> and part of libc.
The API implements DCE 1.1 RPC specification which is
very different from Linux uuid.

Christoph


>
> Signed-off-by: Stefan Weil <weil@mail.berlios.de>
> ---
>  Makefile        |    1 +
>  Makefile.target |    2 ++
>  configure       |   21 +++++++++++++++++++++
>  3 files changed, 24 insertions(+), 0 deletions(-)
>
> diff --git a/Makefile b/Makefile
> index dc95869..d8fa730 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -29,6 +29,7 @@ else
>  DOCS=
>  endif
>
> +LIBS+=$(UUID_LIBS)
>  LIBS+=$(PTHREADLIBS)
>  LIBS+=$(CLOCKLIBS)
>
> diff --git a/Makefile.target b/Makefile.target
> index f9cd42a..4a01e96 100644
> --- a/Makefile.target
> +++ b/Makefile.target
> @@ -469,6 +469,8 @@ ifdef CONFIG_BLUEZ
>  LIBS += $(CONFIG_BLUEZ_LIBS)
>  endif
>
> +LIBS += $(UUID_LIBS)
> +
>  # xen backend driver support
>  obj-$(CONFIG_XEN) += xen_machine_pv.o xen_domainbuild.o
>  ifeq ($(CONFIG_XEN), y)
> diff --git a/configure b/configure
> index 39bed79..28a9c48 100755
> --- a/configure
> +++ b/configure
> @@ -995,6 +995,22 @@ if $cc $ARCH_CFLAGS -o $TMPE $TMPC > /dev/null 2>
> /dev/null ; then fi
>
>  ##########################################
> +# uuid_generate() probe, used for vdi block driver
> +uuid="no"
> +cat > $TMPC << EOF
> +#include <uuid/uuid.h>
> +int main(void)
> +{
> +    uuid_t my_uuid;
> +    uuid_generate(my_uuid);
> +    return 0;
> +}
> +EOF
> +if $cc $ARCH_CFLAGS -o $TMPE $TMPC -luuid >/dev/null 2>&1; then
> +   uuid="yes"
> +fi
> +
> +##########################################
>  # vde libraries probe
>  if test "$vde" = "yes" ; then
>    cat > $TMPC << EOF
> @@ -1473,6 +1489,7 @@ echo "Install blobs     $blobs"
>  echo -e "KVM support       $kvm"
>  echo "fdt support       $fdt"
>  echo "preadv support    $preadv"
> +echo "uuid support      $uuid"
>
>  if test $sdl_too_old = "yes"; then
>  echo "-> Your SDL version is too old - please upgrade to have SDL support"
> @@ -1655,6 +1672,10 @@ fi
>  if test "$fnmatch" = "yes" ; then
>    echo "#define HAVE_FNMATCH_H 1" >> $config_host_h
>  fi
> +if test "$uuid" = "yes" ; then
> +  echo "#define HAVE_UUID_H 1" >> $config_host_h
> +  echo "UUID_LIBS=-luuid" >> $config_host_mak
> +fi
>  qemu_version=`head $source_path/VERSION`
>  echo "VERSION=$qemu_version" >>$config_host_mak
>  echo "#define QEMU_VERSION \"$qemu_version\"" >> $config_host_h



-- 
---to satisfy European Law for business letters:
Advanced Micro Devices GmbH
Karl-Hammerschmidt-Str. 34, 85609 Dornach b. Muenchen
Geschaeftsfuehrer: Thomas M. McCoy, Giuliano Meroni
Sitz: Dornach, Gemeinde Aschheim, Landkreis Muenchen
Registergericht Muenchen, HRB Nr. 43632

Re: [Qemu-devel] [PATCH] Check availability of uuid header / lib

[Stefan Weil]

Christoph Egger schrieb:
> On Thursday 23 July 2009 22:27:54 Stefan Weil wrote:
>   
>> The Universally Unique Identifier library will be used
>> for the new vdi block driver and maybe other parts of QEMU.
>>     
>
> This is very Linux specific.
> On NetBSD, the header is in <sys/uuid.h> and part of libc.
> The API implements DCE 1.1 RPC specification which is
> very different from Linux uuid.
>
> Christoph
>
>   


The Linux implementation claims to conform to OSF DCE 1.1,
see manpages of libuuid.

Do you think that we need a QEMU wrapper to handle different
implementations?

Stefan

Re: [Qemu-devel] [PATCH] Check availability of uuid header / lib

[Christoph Egger]

On Thursday 01 October 2009 20:13:25 Stefan Weil wrote:
> Christoph Egger schrieb:
> > On Thursday 23 July 2009 22:27:54 Stefan Weil wrote:
> >> The Universally Unique Identifier library will be used
> >> for the new vdi block driver and maybe other parts of QEMU.
> >
> > This is very Linux specific.
> > On NetBSD, the header is in <sys/uuid.h> and part of libc.
> > The API implements DCE 1.1 RPC specification which is
> > very different from Linux uuid.
> >
> > Christoph
>
> The Linux implementation claims to conform to OSF DCE 1.1,
> see manpages of libuuid.
>
> Do you think that we need a QEMU wrapper to handle different
> implementations?

Yes. This has already been abstracted in Xen's blktap2 implementation.
You can adapt it to QEMU.

Christoph


-- 
---to satisfy European Law for business letters:
Advanced Micro Devices GmbH
Karl-Hammerschmidt-Str. 34, 85609 Dornach b. Muenchen
Geschaeftsfuehrer: Andrew Bowd, Thomas M. McCoy, Giuliano Meroni
Sitz: Dornach, Gemeinde Aschheim, Landkreis Muenchen
Registergericht Muenchen, HRB Nr. 43632

[Qemu-devel] [PATCH] RFC: Add new block driver for the VDI format

[Stefan Weil]

Hello,

this mail will be followed by two patches which
allow QEMU to create, read and write VDI images.
VDI is the native image format of SUN's VirtualBox emulator.

The code was written from scratch for QEMU, while earlier patches
sent to Qemu-devel were wrappers for code from VirtualBox. See
http://lists.gnu.org/archive/html/qemu-devel/2008-07/msg00366.html
for those patches.

Patch 1 adds uuid support to QEMU and can be used independent of
the second patch (look for uuid in vl.c, for example).

Patch 2 adds the VDI block driver. It only needs uuid support
when a new image is created (without uuid, it will create an image
with zeroed "uuid" values), so this second patch is semi-independent
of the first.

Please test, comment and add both patches to QEMU master
(if there are no objections).

Regards

Stefan Weil

[Qemu-devel] [PATCH] Check availability of uuid header / lib

[Stefan Weil]

The Universally Unique Identifier library will be used
for the new vdi block driver and maybe other parts of QEMU.

Signed-off-by: Stefan Weil <weil@mail.berlios.de>
---
 Makefile        |    1 +
 Makefile.target |    2 ++
 configure       |   21 +++++++++++++++++++++
 3 files changed, 24 insertions(+), 0 deletions(-)

diff --git a/Makefile b/Makefile
index 66c28e5..b6bb41a 100644
--- a/Makefile
+++ b/Makefile
@@ -33,6 +33,7 @@ else
 DOCS=
 endif
 
+LIBS+=$(CONFIG_UUID_LIBS)
 LIBS+=$(PTHREADLIBS)
 LIBS+=$(CLOCKLIBS)
 
diff --git a/Makefile.target b/Makefile.target
index a593503..21f9b3e 100644
--- a/Makefile.target
+++ b/Makefile.target
@@ -541,6 +541,8 @@ ifdef CONFIG_BLUEZ
 LIBS += $(CONFIG_BLUEZ_LIBS)
 endif
 
+LIBS += $(CONFIG_UUID_LIBS)
+
 # xen backend driver support
 obj-$(CONFIG_XEN) += xen_machine_pv.o xen_domainbuild.o
 ifeq ($(CONFIG_XEN), yes)
diff --git a/configure b/configure
index 73cc6b1..aab2c33 100755
--- a/configure
+++ b/configure
@@ -972,6 +972,22 @@ if $cc $ARCH_CFLAGS -o $TMPE $TMPC > /dev/null 2> /dev/null ; then
 fi
 
 ##########################################
+# uuid_generate() probe, used for vdi block driver
+uuid="no"
+cat > $TMPC << EOF
+#include <uuid/uuid.h>
+int main(void)
+{
+    uuid_t my_uuid;
+    uuid_generate(my_uuid);
+    return 0;
+}
+EOF
+if $cc $ARCH_CFLAGS -o $TMPE $TMPC -luuid >/dev/null 2>&1; then
+   uuid="yes"
+fi
+
+##########################################
 # vde libraries probe
 if test "$vde" = "yes" ; then
   cat > $TMPC << EOF
@@ -1453,6 +1469,7 @@ echo "Install blobs     $blobs"
 echo -e "KVM support       $kvm"
 echo "fdt support       $fdt"
 echo "preadv support    $preadv"
+echo "uuid support      $uuid"
 
 if test $sdl_too_old = "yes"; then
 echo "-> Your SDL version is too old - please upgrade to have SDL support"
@@ -1697,6 +1714,10 @@ fi
 if test "$fnmatch" = "yes" ; then
   echo "#define HAVE_FNMATCH_H 1" >> $config_h
 fi
+if test "$uuid" = "yes" ; then
+  echo "#define HAVE_UUID_H 1" >> $config_h
+  echo "CONFIG_UUID_LIBS=-luuid" >> $config_mak
+fi
 qemu_version=`head $source_path/VERSION`
 echo "VERSION=$qemu_version" >>$config_mak
 echo "#define QEMU_VERSION \"$qemu_version\"" >> $config_h
-- 
1.5.6.5