hw/9pfs: add xattr count query interface to fs synth driver

Add a synthetic "/stat/xattr_count" file path that, if being read
by 9p client, returns the 9p server internal xattr FID counter to
client.

This allows to test and verify that the xattr FID limit is being
enforced correctly.

Link: https://lore.kernel.org/qemu-devel/357c20fc244c04dcbd36b13aa20a5c9b2034e9f0.1781361555.git.qemu_oss@crudebyte.com
Signed-off-by: Christian Schoenebeck <qemu_oss@crudebyte.com>
1 file changed