arch/riscv/kernel/vdso/Makefile

   1 # Copied from arch/tile/kernel/vdso/Makefile
   2
   3 # Symbols present in the vdso
   4 vdso-syms = rt_sigreturn
   5
   6 # Files to link into the vdso
   7 obj-vdso = $(patsubst %, %.o, $(vdso-syms))
   8
   9 # Build rules
  10 targets := $(obj-vdso) vdso.so vdso.so.dbg vdso.lds vdso-dummy.o
  11 obj-vdso := $(addprefix $(obj)/, $(obj-vdso))
  12
  13 obj-y += vdso.o vdso-syms.o
  14 CPPFLAGS_vdso.lds += -P -C -U$(ARCH)
  15
  16 # Disable gcov profiling for VDSO code
  17 GCOV_PROFILE := n
  18
  19 # Force dependency
  20 $(obj)/vdso.o: $(obj)/vdso.so
  21
  22 # link rule for the .so file, .lds has to be first
  23 SYSCFLAGS_vdso.so.dbg = $(c_flags)
  24 $(obj)/vdso.so.dbg: $(src)/vdso.lds $(obj-vdso) FORCE
  25         $(call if_changed,vdsold)
  26
  27 # We also create a special relocatable object that should mirror the symbol
  28 # table and layout of the linked DSO.  With ld -R we can then refer to
  29 # these symbols in the kernel code rather than hand-coded addresses.
  30
  31 SYSCFLAGS_vdso.so.dbg = -shared -s -Wl,-soname=linux-vdso.so.1 \
  32                             $(call cc-ldoption, -Wl$(comma)--hash-style=both)
  33 $(obj)/vdso-dummy.o: $(src)/vdso.lds $(obj)/rt_sigreturn.o FORCE
  34         $(call if_changed,vdsold)
  35
  36 LDFLAGS_vdso-syms.o := -r -R
  37 $(obj)/vdso-syms.o: $(obj)/vdso-dummy.o FORCE
  38         $(call if_changed,ld)
  39
  40 # strip rule for the .so file
  41 $(obj)/%.so: OBJCOPYFLAGS := -S
  42 $(obj)/%.so: $(obj)/%.so.dbg FORCE
  43         $(call if_changed,objcopy)
  44
  45 # actual build commands
  46 # The DSO images are built using a special linker script
  47 # Add -lgcc so rv32 gets static muldi3 and lshrdi3 definitions.
  48 # Make sure only to export the intended __vdso_xxx symbol offsets.
  49 quiet_cmd_vdsold = VDSOLD  $@
  50       cmd_vdsold = $(CC) $(KCFLAGS) -nostdlib $(SYSCFLAGS_$(@F)) \
  51                            -Wl,-T,$(filter-out FORCE,$^) -o $@.tmp -lgcc && \
  52                    $(CROSS_COMPILE)objcopy \
  53                            $(patsubst %, -G __vdso_%, $(vdso-syms)) $@.tmp $@
  54
  55 # install commands for the unstripped file
  56 quiet_cmd_vdso_install = INSTALL $@
  57       cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/$@
  58
  59 vdso.so: $(obj)/vdso.so.dbg
  60         @mkdir -p $(MODLIB)/vdso
  61         $(call cmd,vdso_install)
  62
  63 vdso_install: vdso.so