virtiofsd: Add Makefile wiring for virtiofsd contrib

Wire up the building of the virtiofsd in tools.

virtiofsd relies on Linux-specific system calls and seccomp.  Anyone
wishing to port it to other host operating systems should do so
carefully and without reducing security.

Only allow building on Linux hosts.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Liam Merwick <liam.merwick@oracle.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>

Makefile

@@ -327,6 +327,10 @@ HELPERS-y += vhost-user-gpu$(EXESUF)
 vhost-user-json-y += contrib/vhost-user-gpu/50-qemu-gpu.json
 endif
 
+ifdef CONFIG_LINUX
+HELPERS-y += virtiofsd$(EXESUF)
+endif
+
 # Sphinx does not allow building manuals into the same directory as
 # the source files, so if we're doing an in-tree QEMU build we must
 # build the manuals into a subdirectory (and then install them from
@@ -429,6 +433,7 @@ dummy := $(call unnest-vars,, \
                 elf2dmp-obj-y \
                 ivshmem-client-obj-y \
                 ivshmem-server-obj-y \
+                virtiofsd-obj-y \
                 rdmacm-mux-obj-y \
                 libvhost-user-obj-y \
                 vhost-user-scsi-obj-y \
@@ -668,6 +673,11 @@ rdmacm-mux$(EXESUF): LIBS += "-libumad"
 rdmacm-mux$(EXESUF): $(rdmacm-mux-obj-y) $(COMMON_LDADDS)
 	$(call LINK, $^)
 
+ifdef CONFIG_LINUX # relies on Linux-specific syscalls
+virtiofsd$(EXESUF): $(virtiofsd-obj-y) libvhost-user.a $(COMMON_LDADDS)
+	$(call LINK, $^)
+endif
+
 vhost-user-gpu$(EXESUF): $(vhost-user-gpu-obj-y) $(libvhost-user-obj-y) libqemuutil.a libqemustub.a
 	$(call LINK, $^)
 

Makefile.objs

@@ -123,6 +123,7 @@ vhost-user-blk-obj-y = contrib/vhost-user-blk/
 rdmacm-mux-obj-y = contrib/rdmacm-mux/
 vhost-user-input-obj-y = contrib/vhost-user-input/
 vhost-user-gpu-obj-y = contrib/vhost-user-gpu/
+virtiofsd-obj-y = tools/virtiofsd/
 
 ######################################################################
 trace-events-subdirs =

tools/virtiofsd/Makefile.objs

@@ -0,0 +1,9 @@
+virtiofsd-obj-y = buffer.o \
+                  fuse_opt.o \
+                  fuse_log.o \
+                  fuse_lowlevel.o \
+                  fuse_signals.o \
+                  fuse_virtio.o \
+                  helper.o \
+                  passthrough_ll.o
+