If ->write fails, declare migration status as MIG_STATE_ERROR.
Also, in buffered_file.c, ->close the object in case of an
error.
Fixes "migrate -d "exec:dd of=file", where dd fails to open file.
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Luiz Capitulino <lcapitulino@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
QEMUFileBuffered stops writing when the underlying QEMUFile is not ready,
and tells its producer so. However, when the underlying QEMUFile becomes
ready, it neglects to pass that information along, resulting in stoppage
of all data until the next tick (a tenths of a second).
Usually this doesn't matter, because most QEMUFiles used with QEMUFileBuffered
are almost always ready, but in the case of exec: migration this is not true,
due to the small pipe buffers used to connect to the target process. The
result is very slow migration.
Fix by detecting the readiness notification and propagating it. The detection
is a little ugly since QEMUFile overloads put_buffer() to send it, but that's
the suject for a different patch.
Signed-off-by: Avi Kivity <avi@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This patch introduces block migration called during live migration. Block
are being copied to the destination in an async way. First the code will
transfer the whole disk and then transfer all dirty blocks accumulted during
the migration.
Still need to improve transition from the iterative phase of migration to the
end phase. For now transition will take place when all blocks transfered once,
all the dirty blocks will be transfered during the end phase (guest is
suspended).
Changes from v4:
- Global variabels moved to a global state structure allocated dynamically.
- Minor coding style issues.
- Poll block.c for tracking of dirty blocks instead of manage it here.
Signed-off-by: Liran Schour <lirans@il.ibm.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
gcc 4.3.2 throws warnings when DEBUG_BUFFERED_FILE is defined, because
we are using the wrong format specifiers to print size_t/ssize_t values.
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
I used the following command to enable debugging:
perl -p -i -e 's/^\/\/#define DEBUG/#define DEBUG/g' * */* */*/*
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
This patch converts the current callers of qemu_fopen_ops().
Signed-off-by: Glauber Costa <glommer@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
This patch introduces a buffered QEMUFile wrapper. This allows QEMUFile's to be
rate limited. It also makes it easier to implement a QEMUFile that is
asynchronous since the current QEMUFile API requires that all reads and writes
be synchronous.
The only real non-obvious part of the API is the "frozen" concept. If the
backend returns EAGAIN, the QEMUFile is said to be "frozen". This means no
additional output will be sent to the backend until the file is unfrozen.
qemu_file_put_notify can be used to unfreeze a frozen file.
A synchronous interface is also provided to wait for an unfreeze event. This is
used during the final part of live migration when the VM is no longer running.
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5475 c046a42c-6fe2-441c-8c8c-71466251a162
