Compiling NBD kernel module for kernel 3.10.0-514.26.2.el7.x86_64 fails as follows:
# make -C ../../ M=`pwd` nbd.o make: Entering directory `/root/rpmbuild/BUILD/kernel-3.10.0-514.26.2.el7/linux-3.10.0-514.26.2.el7.x86_64' CC /root/rpmbuild/BUILD/kernel-3.10.0-514.26.2.el7/linux-3.10.0-514.26.2.el7.x86_64/drivers/block/nbd.o /root/rpmbuild/BUILD/kernel-3.10.0-514.26.2.el7/linux-3.10.0-514.26.2.el7.x86_64/drivers/block/nbd.c: In function ‘__nbd_ioctl’: /root/rpmbuild/BUILD/kernel-3.10.0-514.26.2.el7/linux-3.10.0-514.26.2.el7.x86_64/drivers/block/nbd.c:619:19: error: ‘REQ_TYPE_SPECIAL’ undeclared (first use in this function) sreq.cmd_type = REQ_TYPE_SPECIAL; ^ /root/rpmbuild/BUILD/kernel-3.10.0-514.26.2.el7/linux-3.10.0-514.26.2.el7.x86_64/drivers/block/nbd.c:619:19: note: each undeclared identifier is reported only once for each function it appears in make[1]: *** [/root/rpmbuild/BUILD/kernel-3.10.0-514.26.2.el7/linux-3.10.0-514.26.2.el7.x86_64/drivers/block/nbd.o] Error 1 make: *** [nbd.o] Error 2 make: Leaving directory `/root/rpmbuild/BUILD/kernel-3.10.0-514.26.2.el7/linux-3.10.0-514.26.2.el7.x86_64'
Was support for NBD dropped or was this just a human error?