1# SPDX-License-Identifier: GPL-2.0-only 2# Copied from arch/tile/kernel/vdso/Makefile 3 4# Symbols present in the vdso 5vdso-syms = rt_sigreturn 6ifdef CONFIG_64BIT 7vdso-syms += gettimeofday 8vdso-syms += clock_gettime 9vdso-syms += clock_getres 10endif 11vdso-syms += getcpu 12vdso-syms += flush_icache 13 14# Files to link into the vdso 15obj-vdso = $(patsubst %, %.o, $(vdso-syms)) note.o 16 17# Build rules 18targets := $(obj-vdso) vdso.so vdso.so.dbg vdso.lds vdso-dummy.o 19obj-vdso := $(addprefix $(obj)/, $(obj-vdso)) 20 21obj-y += vdso.o vdso-syms.o 22CPPFLAGS_vdso.lds += -P -C -U$(ARCH) 23 24# Disable gcov profiling for VDSO code 25GCOV_PROFILE := n 26 27# Force dependency 28$(obj)/vdso.o: $(obj)/vdso.so 29 30# link rule for the .so file, .lds has to be first 31SYSCFLAGS_vdso.so.dbg = $(c_flags) 32$(obj)/vdso.so.dbg: $(src)/vdso.lds $(obj-vdso) FORCE 33 $(call if_changed,vdsold) 34 35# We also create a special relocatable object that should mirror the symbol 36# table and layout of the linked DSO. With ld --just-symbols we can then 37# refer to these symbols in the kernel code rather than hand-coded addresses. 38 39SYSCFLAGS_vdso.so.dbg = -shared -s -Wl,-soname=linux-vdso.so.1 \ 40 -Wl,--build-id -Wl,--hash-style=both 41$(obj)/vdso-dummy.o: $(src)/vdso.lds $(obj)/rt_sigreturn.o FORCE 42 $(call if_changed,vdsold) 43 44LDFLAGS_vdso-syms.o := -r --just-symbols 45$(obj)/vdso-syms.o: $(obj)/vdso-dummy.o FORCE 46 $(call if_changed,ld) 47 48# strip rule for the .so file 49$(obj)/%.so: OBJCOPYFLAGS := -S 50$(obj)/%.so: $(obj)/%.so.dbg FORCE 51 $(call if_changed,objcopy) 52 53# actual build commands 54# The DSO images are built using a special linker script 55# Add -lgcc so rv32 gets static muldi3 and lshrdi3 definitions. 56# Make sure only to export the intended __vdso_xxx symbol offsets. 57quiet_cmd_vdsold = VDSOLD $@ 58 cmd_vdsold = $(CC) $(KBUILD_CFLAGS) $(call cc-option, -no-pie) -nostdlib -nostartfiles $(SYSCFLAGS_$(@F)) \ 59 -Wl,-T,$(filter-out FORCE,$^) -o $@.tmp && \ 60 $(CROSS_COMPILE)objcopy \ 61 $(patsubst %, -G __vdso_%, $(vdso-syms)) $@.tmp $@ && \ 62 rm $@.tmp 63 64# install commands for the unstripped file 65quiet_cmd_vdso_install = INSTALL $@ 66 cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/$@ 67 68vdso.so: $(obj)/vdso.so.dbg 69 @mkdir -p $(MODLIB)/vdso 70 $(call cmd,vdso_install) 71 72vdso_install: vdso.so 73