arch/mips/vdso/Makefile

   1 # SPDX-License-Identifier: GPL-2.0
   2 # Objects to go into the VDSO.
   3
   4 # Absolute relocation type $(ARCH_REL_TYPE_ABS) needs to be defined before
   5 # the inclusion of generic Makefile.
   6 ARCH_REL_TYPE_ABS := R_MIPS_JUMP_SLOT|R_MIPS_GLOB_DAT
   7 include $(srctree)/lib/vdso/Makefile
   8
   9 obj-vdso-y := elf.o vgettimeofday.o sigreturn.o
  10
  11 # Common compiler flags between ABIs.
  12 ccflags-vdso := \
  13         $(filter -I%,$(KBUILD_CFLAGS)) \
  14         $(filter -E%,$(KBUILD_CFLAGS)) \
  15         $(filter -mmicromips,$(KBUILD_CFLAGS)) \
  16         $(filter -march=%,$(KBUILD_CFLAGS)) \
  17         $(filter -m%-float,$(KBUILD_CFLAGS)) \
  18         $(filter -mno-loongson-%,$(KBUILD_CFLAGS)) \
  19         -D__VDSO__
  20
  21 ifndef CONFIG_64BIT
  22 ccflags-vdso += -DBUILD_VDSO32
  23 endif
  24
  25 ifdef CONFIG_CC_IS_CLANG
  26 ccflags-vdso += $(filter --target=%,$(KBUILD_CFLAGS))
  27 endif
  28
  29 #
  30 # The -fno-jump-tables flag only prevents the compiler from generating
  31 # jump tables but does not prevent the compiler from emitting absolute
  32 # offsets.
  33 cflags-vdso := $(ccflags-vdso) \
  34         $(filter -W%,$(filter-out -Wa$(comma)%,$(KBUILD_CFLAGS))) \
  35         -O3 -g -fPIC -fno-strict-aliasing -fno-common -fno-builtin -G 0 \
  36         -mrelax-pic-calls $(call cc-option, -mexplicit-relocs) \
  37         -fno-stack-protector -fno-jump-tables -DDISABLE_BRANCH_PROFILING \
  38         $(call cc-option, -fno-asynchronous-unwind-tables) \
  39         $(call cc-option, -fno-stack-protector)
  40 aflags-vdso := $(ccflags-vdso) \
  41         -D__ASSEMBLY__ -Wa,-gdwarf-2
  42
  43 ifneq ($(c-gettimeofday-y),)
  44 CFLAGS_vgettimeofday.o = -include $(c-gettimeofday-y)
  45
  46 # config-n32-o32-env.c prepares the environment to build a 32bit vDSO
  47 # library on a 64bit kernel.
  48 # Note: Needs to be included before than the generic library.
  49 CFLAGS_vgettimeofday-o32.o = -include $(srctree)/$(src)/config-n32-o32-env.c -include $(c-gettimeofday-y)
  50 CFLAGS_vgettimeofday-n32.o = -include $(srctree)/$(src)/config-n32-o32-env.c -include $(c-gettimeofday-y)
  51 endif
  52
  53 CFLAGS_REMOVE_vgettimeofday.o = -pg
  54
  55 DISABLE_VDSO := n
  56
  57 #
  58 # For the pre-R6 code in arch/mips/vdso/vdso.h for locating
  59 # the base address of VDSO, the linker will emit a R_MIPS_PC32
  60 # relocation in binutils > 2.25 but it will fail with older versions
  61 # because that relocation is not supported for that symbol. As a result
  62 # of which we are forced to disable the VDSO symbols when building
  63 # with < 2.25 binutils on pre-R6 kernels. For more references on why we
  64 # can't use other methods to get the base address of VDSO please refer to
  65 # the comments on that file.
  66 #
  67 ifndef CONFIG_CPU_MIPSR6
  68   ifeq ($(call ld-ifversion, -lt, 225000000, y),y)
  69     $(warning MIPS VDSO requires binutils >= 2.25)
  70     DISABLE_VDSO := y
  71   endif
  72 endif
  73
  74 #
  75 # GCC (at least up to version 9.2) appears to emit function calls that make use
  76 # of the GOT when targeting microMIPS, which we can't use in the VDSO due to
  77 # the lack of relocations. As such, we disable the VDSO for microMIPS builds.
  78 #
  79 ifdef CONFIG_CPU_MICROMIPS
  80   DISABLE_VDSO := y
  81 endif
  82
  83 ifeq ($(DISABLE_VDSO),y)
  84   obj-vdso-y := $(filter-out vgettimeofday.o, $(obj-vdso-y))
  85   ccflags-vdso += -DDISABLE_MIPS_VDSO
  86 endif
  87
  88 # VDSO linker flags.
  89 VDSO_LDFLAGS := \
  90         -Wl,-Bsymbolic -Wl,--no-undefined -Wl,-soname=linux-vdso.so.1 \
  91         $(addprefix -Wl$(comma),$(filter -E%,$(KBUILD_CFLAGS))) \
  92         -nostdlib -shared -Wl,--hash-style=sysv -Wl,--build-id
  93
  94 CFLAGS_REMOVE_vdso.o = -pg
  95
  96 GCOV_PROFILE := n
  97 UBSAN_SANITIZE := n
  98 KCOV_INSTRUMENT := n
  99
 100 # Check that we don't have PIC 'jalr t9' calls left
 101 quiet_cmd_vdso_mips_check = VDSOCHK $@
 102       cmd_vdso_mips_check = if $(OBJDUMP) --disassemble $@ | egrep -h "jalr.*t9" > /dev/null; \
 103                        then (echo >&2 "$@: PIC 'jalr t9' calls are not supported"; \
 104                              rm -f $@; /bin/false); fi
 105
 106 #
 107 # Shared build commands.
 108 #
 109
 110 quiet_cmd_vdsold_and_vdso_check = LD      $@
 111       cmd_vdsold_and_vdso_check = $(cmd_vdsold); $(cmd_vdso_check); $(cmd_vdso_mips_check)
 112
 113 quiet_cmd_vdsold = VDSO    $@
 114       cmd_vdsold = $(CC) $(c_flags) $(VDSO_LDFLAGS) \
 115                    -Wl,-T $(filter %.lds,$^) $(filter %.o,$^) -o $@
 116
 117 quiet_cmd_vdsoas_o_S = AS      $@
 118       cmd_vdsoas_o_S = $(CC) $(a_flags) -c -o $@ $<
 119
 120 # Strip rule for the raw .so files
 121 $(obj)/%.so.raw: OBJCOPYFLAGS := -S
 122 $(obj)/%.so.raw: $(obj)/%.so.dbg.raw FORCE
 123         $(call if_changed,objcopy)
 124
 125 hostprogs := genvdso
 126
 127 quiet_cmd_genvdso = GENVDSO $@
 128 define cmd_genvdso
 129         $(foreach file,$(filter %.raw,$^),cp $(file) $(file:%.raw=%) &&) \
 130         $(obj)/genvdso $(<:%.raw=%) $(<:%.dbg.raw=%) $@ $(VDSO_NAME)
 131 endef
 132
 133 #
 134 # Build native VDSO.
 135 #
 136
 137 native-abi := $(filter -mabi=%,$(KBUILD_CFLAGS))
 138
 139 targets += $(obj-vdso-y)
 140 targets += vdso.lds
 141 targets += vdso.so.dbg.raw vdso.so.raw
 142 targets += vdso.so.dbg vdso.so
 143 targets += vdso-image.c
 144
 145 obj-vdso := $(obj-vdso-y:%.o=$(obj)/%.o)
 146
 147 $(obj-vdso): KBUILD_CFLAGS := $(cflags-vdso) $(native-abi)
 148 $(obj-vdso): KBUILD_AFLAGS := $(aflags-vdso) $(native-abi)
 149
 150 $(obj)/vdso.lds: KBUILD_CPPFLAGS := $(ccflags-vdso) $(native-abi)
 151
 152 $(obj)/vdso.so.dbg.raw: $(obj)/vdso.lds $(obj-vdso) FORCE
 153         $(call if_changed,vdsold_and_vdso_check)
 154
 155 $(obj)/vdso-image.c: $(obj)/vdso.so.dbg.raw $(obj)/vdso.so.raw \
 156                      $(obj)/genvdso FORCE
 157         $(call if_changed,genvdso)
 158
 159 obj-y += vdso-image.o
 160
 161 #
 162 # Build O32 VDSO.
 163 #
 164
 165 # Define these outside the ifdef to ensure they are picked up by clean.
 166 targets += $(obj-vdso-y:%.o=%-o32.o)
 167 targets += vdso-o32.lds
 168 targets += vdso-o32.so.dbg.raw vdso-o32.so.raw
 169 targets += vdso-o32.so.dbg vdso-o32.so
 170 targets += vdso-o32-image.c
 171
 172 ifdef CONFIG_MIPS32_O32
 173
 174 obj-vdso-o32 := $(obj-vdso-y:%.o=$(obj)/%-o32.o)
 175
 176 $(obj-vdso-o32): KBUILD_CFLAGS := $(cflags-vdso) -mabi=32
 177 $(obj-vdso-o32): KBUILD_AFLAGS := $(aflags-vdso) -mabi=32
 178
 179 $(obj)/%-o32.o: $(src)/%.S FORCE
 180         $(call if_changed_dep,vdsoas_o_S)
 181
 182 $(obj)/%-o32.o: $(src)/%.c FORCE
 183         $(call cmd,force_checksrc)
 184         $(call if_changed_rule,cc_o_c)
 185
 186 $(obj)/vdso-o32.lds: KBUILD_CPPFLAGS := $(ccflags-vdso) -mabi=32
 187 $(obj)/vdso-o32.lds: $(src)/vdso.lds.S FORCE
 188         $(call if_changed_dep,cpp_lds_S)
 189
 190 $(obj)/vdso-o32.so.dbg.raw: $(obj)/vdso-o32.lds $(obj-vdso-o32) FORCE
 191         $(call if_changed,vdsold_and_vdso_check)
 192
 193 $(obj)/vdso-o32-image.c: VDSO_NAME := o32
 194 $(obj)/vdso-o32-image.c: $(obj)/vdso-o32.so.dbg.raw $(obj)/vdso-o32.so.raw \
 195                          $(obj)/genvdso FORCE
 196         $(call if_changed,genvdso)
 197
 198 obj-y += vdso-o32-image.o
 199
 200 endif
 201
 202 #
 203 # Build N32 VDSO.
 204 #
 205
 206 targets += $(obj-vdso-y:%.o=%-n32.o)
 207 targets += vdso-n32.lds
 208 targets += vdso-n32.so.dbg.raw vdso-n32.so.raw
 209 targets += vdso-n32.so.dbg vdso-n32.so
 210 targets += vdso-n32-image.c
 211
 212 ifdef CONFIG_MIPS32_N32
 213
 214 obj-vdso-n32 := $(obj-vdso-y:%.o=$(obj)/%-n32.o)
 215
 216 $(obj-vdso-n32): KBUILD_CFLAGS := $(cflags-vdso) -mabi=n32
 217 $(obj-vdso-n32): KBUILD_AFLAGS := $(aflags-vdso) -mabi=n32
 218
 219 $(obj)/%-n32.o: $(src)/%.S FORCE
 220         $(call if_changed_dep,vdsoas_o_S)
 221
 222 $(obj)/%-n32.o: $(src)/%.c FORCE
 223         $(call cmd,force_checksrc)
 224         $(call if_changed_rule,cc_o_c)
 225
 226 $(obj)/vdso-n32.lds: KBUILD_CPPFLAGS := $(ccflags-vdso) -mabi=n32
 227 $(obj)/vdso-n32.lds: $(src)/vdso.lds.S FORCE
 228         $(call if_changed_dep,cpp_lds_S)
 229
 230 $(obj)/vdso-n32.so.dbg.raw: $(obj)/vdso-n32.lds $(obj-vdso-n32) FORCE
 231         $(call if_changed,vdsold_and_vdso_check)
 232
 233 $(obj)/vdso-n32-image.c: VDSO_NAME := n32
 234 $(obj)/vdso-n32-image.c: $(obj)/vdso-n32.so.dbg.raw $(obj)/vdso-n32.so.raw \
 235                          $(obj)/genvdso FORCE
 236         $(call if_changed,genvdso)
 237
 238 obj-y += vdso-n32-image.o
 239
 240 endif
 241
 242 # FIXME: Need install rule for debug.
 243 # Needs to deal with dependency for generation of dbg by cmd_genvdso...