675de5aa37
The name of the flag used to mark a bio as synchronous has changed again in the 2.6.36 kernel due to the unification of the BIO_RW_* and REQ_* flags. The new flag is called REQ_SYNC. To simplify checking this flag I have introduced the vdev_disk_dio_is_sync() helper function. Based on the results of several new autoconf tests it uses the correct mask to check for a synchronous bio. Preferred interface for flagging a synchronous bio: 2.6.12-2.6.29: BIO_RW_SYNC 2.6.30-2.6.35: BIO_RW_SYNCIO 2.6.36-2.6.xx: REQ_SYNC