arch/csky/kernel/vdso/Makefile

   1 # SPDX-License-Identifier: GPL-2.0-only
   2
   3 # Include the generic Makefile to check the built vdso.
   4 include $(srctree)/lib/vdso/Makefile
   5
   6 # Symbols present in the vdso
   7 vdso-syms  += rt_sigreturn
   8 vdso-syms  += vgettimeofday
   9
  10 # Files to link into the vdso
  11 obj-vdso = $(patsubst %, %.o, $(vdso-syms)) note.o
  12
  13 ifneq ($(c-gettimeofday-y),)
  14         CFLAGS_vgettimeofday.o += -include $(c-gettimeofday-y)
  15 endif
  16
  17 ccflags-y := -fno-stack-protector -DBUILD_VDSO32
  18
  19 # Build rules
  20 targets := $(obj-vdso) vdso.so vdso.so.dbg vdso.lds vdso-dummy.o
  21 obj-vdso := $(addprefix $(obj)/, $(obj-vdso))
  22
  23 obj-y += vdso.o vdso-syms.o
  24 CPPFLAGS_vdso.lds += -P -C -U$(ARCH)
  25
  26 # Force dependency
  27 $(obj)/vdso.o: $(obj)/vdso.so
  28
  29 SYSCFLAGS_vdso.so.dbg = $(c_flags)
  30 $(obj)/vdso.so.dbg: $(obj)/vdso.lds $(obj-vdso) FORCE
  31         $(call if_changed,vdsold)
  32 SYSCFLAGS_vdso.so.dbg = -shared -s -Wl,-soname=linux-vdso.so.1 \
  33         -Wl,--build-id=sha1 -Wl,--hash-style=both
  34
  35 $(obj)/vdso-syms.S: $(obj)/vdso.so FORCE
  36         $(call if_changed,so2s)
  37
  38 # strip rule for the .so file
  39 $(obj)/%.so: OBJCOPYFLAGS := -S
  40 $(obj)/%.so: $(obj)/%.so.dbg FORCE
  41         $(call if_changed,objcopy)
  42
  43 # actual build commands
  44 # The DSO images are built using a special linker script
  45 # Make sure only to export the intended __vdso_xxx symbol offsets.
  46 quiet_cmd_vdsold = VDSOLD  $@
  47       cmd_vdsold = $(CC) $(KBUILD_CFLAGS) $(call cc-option, -no-pie) -nostdlib -nostartfiles $(SYSCFLAGS_$(@F)) \
  48                            -Wl,-T,$(filter-out FORCE,$^) -o $@.tmp && \
  49                    $(CROSS_COMPILE)objcopy \
  50                            $(patsubst %, -G __vdso_%, $(vdso-syms)) $@.tmp $@ && \
  51                    rm $@.tmp
  52
  53 # Extracts symbol offsets from the VDSO, converting them into an assembly file
  54 # that contains the same symbols at the same offsets.
  55 quiet_cmd_so2s = SO2S    $@
  56       cmd_so2s = $(NM) -D $< | $(src)/so2s.sh > $@