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)) 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) 23ifneq ($(filter vgettimeofday, $(vdso-syms)),) 24CPPFLAGS_vdso.lds += -DHAS_VGETTIMEOFDAY 25endif 26 27# Disable gcov profiling for VDSO code 28GCOV_PROFILE := n 29 30# Force dependency 31$(obj)/vdso.o: $(obj)/vdso.so 32 33# link rule for the .so file, .lds has to be first 34SYSCFLAGS_vdso.so.dbg = $(c_flags) 35$(obj)/vdso.so.dbg: $(src)/vdso.lds $(obj-vdso) FORCE 36 $(call if_changed,vdsold) 37 38# We also create a special relocatable object that should mirror the symbol 39# table and layout of the linked DSO. With ld --just-symbols we can then 40# refer to these symbols in the kernel code rather than hand-coded addresses. 41 42SYSCFLAGS_vdso.so.dbg = -shared -s -Wl,-soname=linux-vdso.so.1 \ 43 -Wl,--build-id -Wl,--hash-style=both 44$(obj)/vdso-dummy.o: $(src)/vdso.lds $(obj)/rt_sigreturn.o FORCE 45 $(call if_changed,vdsold) 46 47LDFLAGS_vdso-syms.o := -r --just-symbols 48$(obj)/vdso-syms.o: $(obj)/vdso-dummy.o FORCE 49 $(call if_changed,ld) 50 51# strip rule for the .so file 52$(obj)/%.so: OBJCOPYFLAGS := -S 53$(obj)/%.so: $(obj)/%.so.dbg FORCE 54 $(call if_changed,objcopy) 55 56# actual build commands 57# The DSO images are built using a special linker script 58# Add -lgcc so rv32 gets static muldi3 and lshrdi3 definitions. 59# Make sure only to export the intended __vdso_xxx symbol offsets. 60quiet_cmd_vdsold = VDSOLD $@ 61 cmd_vdsold = $(CC) $(KBUILD_CFLAGS) $(call cc-option, -no-pie) -nostdlib -nostartfiles $(SYSCFLAGS_$(@F)) \ 62 -Wl,-T,$(filter-out FORCE,$^) -o $@.tmp && \ 63 $(CROSS_COMPILE)objcopy \ 64 $(patsubst %, -G __vdso_%, $(vdso-syms)) $@.tmp $@ && \ 65 rm $@.tmp 66 67# install commands for the unstripped file 68quiet_cmd_vdso_install = INSTALL $@ 69 cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/$@ 70 71vdso.so: $(obj)/vdso.so.dbg 72 @mkdir -p $(MODLIB)/vdso 73 $(call cmd,vdso_install) 74 75vdso_install: vdso.so 76