arch/x86/vdso/Makefile

   1 #
   2 # x86-64 vDSO.
   3 #
   4
   5 # files to link into the vdso
   6 # vdso-start.o has to be first
   7 vobjs-y := vdso-start.o vdso-note.o vclock_gettime.o vgetcpu.o vvar.o
   8
   9 # files to link into kernel
  10 obj-y := vma.o vdso.o vdso-syms.o
  11
  12 vobjs := $(foreach F,$(vobjs-y),$(obj)/$F)
  13
  14 $(obj)/vdso.o: $(obj)/vdso.so
  15
  16 targets += vdso.so vdso.lds $(vobjs-y) vdso-syms.o
  17
  18 # The DSO images are built using a special linker script.
  19 quiet_cmd_syscall = SYSCALL $@
  20       cmd_syscall = $(CC) -m elf_x86_64 -nostdlib $(SYSCFLAGS_$(@F)) \
  21                           -Wl,-T,$(filter-out FORCE,$^) -o $@
  22
  23 export CPPFLAGS_vdso.lds += -P -C -U$(ARCH)
  24
  25 vdso-flags = -fPIC -shared -Wl,-soname=linux-vdso.so.1 \
  26                  $(call ld-option, -Wl$(comma)--hash-style=sysv) \
  27                 -Wl,-z,max-page-size=4096 -Wl,-z,common-page-size=4096
  28 SYSCFLAGS_vdso.so = $(vdso-flags)
  29
  30 $(obj)/vdso.o: $(src)/vdso.S $(obj)/vdso.so
  31
  32 $(obj)/vdso.so: $(src)/vdso.lds $(vobjs) FORCE
  33         $(call if_changed,syscall)
  34
  35 CFL := $(PROFILING) -mcmodel=small -fPIC -g0 -O2 -fasynchronous-unwind-tables -m64
  36
  37 $(obj)/vclock_gettime.o: KBUILD_CFLAGS = $(CFL)
  38 $(obj)/vgetcpu.o: KBUILD_CFLAGS = $(CFL)
  39
  40 # We also create a special relocatable object that should mirror the symbol
  41 # table and layout of the linked DSO.  With ld -R we can then refer to
  42 # these symbols in the kernel code rather than hand-coded addresses.
  43 extra-y += vdso-syms.o
  44 $(obj)/built-in.o: $(obj)/vdso-syms.o
  45 $(obj)/built-in.o: ld_flags += -R $(obj)/vdso-syms.o
  46
  47 SYSCFLAGS_vdso-syms.o = -r -d
  48 $(obj)/vdso-syms.o: $(src)/vdso.lds $(vobjs) FORCE
  49         $(call if_changed,syscall)