kbuild: Accept absolute paths in clean-files and introduce clean-dirs

Teach kbuild to accept absolute paths in clean-files. This avoids using
clean-rules in several places.
Introduced clean-dirs to delete complete directories.
Kept clean-rule - but do not print anything when used.
Cleaned up a few places now the infrastructure are improved.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>

Documentation/DocBook/Makefile

@@ -185,9 +185,7 @@ clean-files := $(DOCBOOKS) \
 	$(patsubst %.sgml, %.9,    $(DOCBOOKS)) \
 	$(C-procfs-example)
 
-ifneq ($(wildcard $(patsubst %.html,%,$(HTML))),)
-clean-rule := rm -rf $(wildcard $(patsubst %.html,%,$(HTML)))
-endif
+clean-dirs := $(patsubst %.sgml,%,$(DOCBOOKS))
 
 #man put files in man subdir - traverse down
 subdir- := man/

Documentation/kbuild/makefiles.txt

@@ -547,8 +547,17 @@ Additional files can be specified in kbuild makefiles by use of $(clean-files).
 		clean-files := devlist.h classlist.h
 
 When executing "make clean", the two files "devlist.h classlist.h" will
-be deleted. Kbuild knows that files specified by $(clean-files) are
-located in the same directory as the makefile.
+be deleted. Kbuild will assume files to be in same relative directory as the
+Makefile except if an absolute path is specified (path starting with '/').
+
+To delete a directory hirachy use:
+	Example:
+		#scripts/package/Makefile
+		clean-dirs := $(objtree)/debian/
+
+This will delete the directory debian, including all subdirectories.
+Kbuild will assume the directories to be in the same relative path as the
+Makefile if no absolute path is specified (path does not start with '/').
 
 Usually kbuild descends down in subdirectories due to "obj-* := dir/",
 but in the architecture makefiles where the kbuild infrastructure

scripts/Makefile.clean

@@ -29,21 +29,35 @@ subdir-ymn      := $(sort $(subdir-ym) $(subdir-n) $(subdir-))
 # Add subdir path
 
 subdir-ymn	:= $(addprefix $(obj)/,$(subdir-ymn))
-__clean-files	:= $(wildcard $(addprefix $(obj)/, \
-		   $(extra-y) $(EXTRA_TARGETS) $(always) $(host-progs) \
-		   $(targets) $(clean-files)))
+__clean-files	:= $(extra-y) $(EXTRA_TARGETS) $(always) $(host-progs) \
+		   $(targets) $(clean-files)
+__clean-files   := $(wildcard                                               \
+                   $(addprefix $(obj)/, $(filter-out /%, $(__clean-files))) \
+		   $(filter /%, $(__clean-files)))
+__clean-dirs    := $(wildcard                                               \
+                   $(addprefix $(obj)/, $(filter-out /%, $(clean-dirs)))    \
+		   $(filter /%, $(clean-dirs)))
 
 # ==========================================================================
 
-quiet_cmd_clean = CLEAN   $(obj)
-      cmd_clean = rm -f $(__clean-files); $(clean-rule)
+quiet_cmd_clean    = CLEAN   $(obj)
+      cmd_clean    = rm -f $(__clean-files)
+quiet_cmd_cleandir = CLEAN   $(__clean-dirs)
+      cmd_cleandir = rm -rf $(__clean-dirs)
+
 
 __clean: $(subdir-ymn)
-ifneq ($(strip $(__clean-files) $(clean-rule)),)
+ifneq ($(strip $(__clean-files)),)
 	+$(call cmd,clean)
-else
-	@:
 endif
+ifneq ($(strip $(__clean-dirs)),)
+	+$(call cmd,cleandir)
+endif
+ifneq ($(strip $(clean-rule)),)
+	+$(clean-rule)
+endif
+	@:
+
 
 # ===========================================================================
 # Generic stuff

scripts/package/Makefile

@@ -51,7 +51,7 @@ rpm-pkg rpm: $(objtree)/kernel.spec
 	$(RPM) --target $(UTS_MACHINE) -ta ../$(KERNELPATH).tar.gz
 	rm ../$(KERNELPATH).tar.gz
 
-clean-rule +=  rm -f $(objtree)/kernel.spec
+clean-files := $(objtree)/kernel.spec
 
 # binrpm-pkg
 .PHONY: binrpm-pkg
@@ -67,7 +67,7 @@ binrpm-pkg: $(objtree)/binkernel.spec
 
 	$(RPM) --define "_builddir $(srctree)" --target $(UTS_MACHINE) -bb $<
 
-clean-rule += rm -f $(objtree)/binkernel.spec
+clean-files += $(objtree)/binkernel.spec
 
 # Deb target
 # ---------------------------------------------------------------------------
@@ -77,7 +77,7 @@ deb-pkg:
 	$(MAKE)
 	$(CONFIG_SHELL) $(srctree)/scripts/package/builddeb
 
-clean-rule += && rm -rf $(objtree)/debian/
+clean-dirs += $(objtree)/debian/
 
 
 # Help text displayed when executing 'make help'