On Tue, Jul 04, 2023 at 02:34:36PM +0200, Stefan Hajnoczi wrote:
When QEMU is built with --enable-modules, the module_block.py script parses block/*.c to find block drivers that are built as modules. The script generates a table of block drivers called block_driver_modules[]. This table is used for block driver module loading.The blkio.c driver uses macros to define its BlockDriver structs. This was done to avoid code duplication but the module_block.py script is unable to parse the macro. The result is that libblkio-based block drivers can be built as modules but will not be found at runtime. One fix is to make the module_block.py script or build system fancier so it can parse C macros (e.g. by parsing the preprocessed source code). I chose not to do this because it raises the complexity of the build, making future issues harder to debug. Keep things simple: use the macro to avoid duplicating BlockDriver function pointers but define .format_name and .protocol_name manually for each BlockDriver. This way the module_block.py is able to parse the code. Also get rid of the block driver name macros (e.g. DRIVER_IO_URING) because module_block.py cannot parse them either. Fixes: fd66dbd424f5 ("blkio: add libblkio block driver") Reported-by: Qing Wang <qinw...@redhat.com> Cc: Stefano Garzarella <sgarz...@redhat.com> Signed-off-by: Stefan Hajnoczi <stefa...@redhat.com> --- v2: - Drop unnecessary backslashes [Stefano] --- block/blkio.c | 108 ++++++++++++++++++++++++++------------------------ 1 file changed, 56 insertions(+), 52 deletions(-)
Reviewed-by: Stefano Garzarella <sgarz...@redhat.com>
