qemu-img: Omit error_report() after img_open()

img_open() already prints an error if the operation failed, so there
should not be another error_report() afterwards.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
block: Propagate error in bdrv_img_create()

If the specified backing file could not be opened, do not generate a new
error message which contains the message which has been generated by
bdrv_open(), but just propagate the latter.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
iotests: Add test for non-existing backing file

Test the error message when a COW file is about to be created which is
supposed to inherit the size of its backing file, while the backing file
given does not actually exist.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Peter Lieven <pl@kamp.de>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
qapi: Complete BlkdebugEvent

Several events were missing from the QAPI enum, add them.

Reported-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
block/vdi: Limit maximum size even futher

The block layer read and write functions do not like requests which are
bigger than INT_MAX bytes. Since the VDI bmap is read and written in a
single operation, its size is therefore limited accordingly. This
reduces the maximum VDI image size supported by QEMU to half of what it
currently is (down to approximately 512 TB).

The VDI test 084 has to be adapted accordingly. Actually, one could
clearly see that it was broken from the "Could not open
'TEST_DIR/t.IMGFMT': Invalid argument" line for an image which was
supposed to work just fine.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Peter Lieven <pl@kamp.de>
Merge remote-tracking branch 'mreitz/block' into queue-block

* mreitz/block:
  block/vdi: Limit maximum size even futher
Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging

Block patches

# gpg: Signature made Mon 10 Nov 2014 09:42:07 GMT using RSA key ID C88F2FD6
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>"

* remotes/kevin/tags/for-upstream:
  block/vdi: Limit maximum size even futher
  qapi: Complete BlkdebugEvent
  iotests: Add test for non-existing backing file
  block: Propagate error in bdrv_img_create()
  qemu-img: Omit error_report() after img_open()

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>