aboutsummaryrefslogtreecommitdiffstats
path: root/arch/x86/vdso/Makefile
blob: 5d179502a52cce8ee6b9f8f5fe643a35e0bf472a (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
#
# Building vDSO images for x86.
#

VDSO64-$(CONFIG_X86_64)		:= y
VDSO32-$(CONFIG_X86_32)		:= y
VDSO32-$(CONFIG_COMPAT)		:= y

vdso-install-$(VDSO64-y)	+= vdso.so
vdso-install-$(VDSO32-y)	+= $(vdso32-images)


# files to link into the vdso
vobjs-y := vdso-note.o vclock_gettime.o vgetcpu.o

# files to link into kernel
obj-$(VDSO64-y)			+= vma.o vdso.o
obj-$(VDSO32-y)			+= vdso32.o vdso32-setup.o

vobjs := $(foreach F,$(vobjs-y),$(obj)/$F)

$(obj)/vdso.o: $(obj)/vdso.so

targets += vdso.so vdso.so.dbg vdso.lds $(vobjs-y)

export CPPFLAGS_vdso.lds += -P -C

VDSO_LDFLAGS_vdso.lds = -m64 -Wl,-soname=linux-vdso.so.1 \
			-Wl,--no-undefined \
		      	-Wl,-z,max-page-size=4096 -Wl,-z,common-page-size=4096

$(obj)/vdso.o: $(src)/vdso.S $(obj)/vdso.so

$(obj)/vdso.so.dbg: $(src)/vdso.lds $(vobjs) FORCE
	$(call if_changed,vdso)

$(obj)/%.so: OBJCOPYFLAGS := -S
$(obj)/%.so: $(obj)/%.so.dbg FORCE
	$(call if_changed,objcopy)

#
# Don't omit frame pointers for ease of userspace debugging, but do
# optimize sibling calls.
#
CFL := $(PROFILING) -mcmodel=small -fPIC -O2 -fasynchronous-unwind-tables -m64 \
       $(filter -g%,$(KBUILD_CFLAGS)) $(call cc-option, -fno-stack-protector) \
       -fno-omit-frame-pointer -foptimize-sibling-calls

$(vobjs): KBUILD_CFLAGS += $(CFL)

#
# vDSO code runs in userspace and -pg doesn't help with profiling anyway.
#
CFLAGS_REMOVE_vdso-note.o = -pg
CFLAGS_REMOVE_vclock_gettime.o = -pg
CFLAGS_REMOVE_vgetcpu.o = -pg
CFLAGS_REMOVE_vvar.o = -pg

targets += vdso-syms.lds
obj-$(VDSO64-y)			+= vdso-syms.lds

#
# Match symbols in the DSO that look like VDSO*; produce a file of constants.
#
sed-vdsosym := -e 's/^00*/0/' \
	-e 's/^\([0-9a-fA-F]*\) . \(VDSO[a-zA-Z0-9_]*\)$$/\2 = 0x\1;/p'
quiet_cmd_vdsosym = VDSOSYM $@
define cmd_vdsosym
	$(NM) $< | LC_ALL=C sed -n $(sed-vdsosym) | LC_ALL=C sort > $@
endef

$(obj)/%-syms.lds: $(obj)/%.so.dbg FORCE
	$(call if_changed,vdsosym)

#
# Build multiple 32-bit vDSO images to choose from at boot time.
#
obj-$(VDSO32-y)			+= vdso32-syms.lds
vdso32.so-$(VDSO32-y)		+= int80
vdso32.so-$(CONFIG_COMPAT)	+= syscall
vdso32.so-$(VDSO32-y)		+= sysenter

vdso32-images			= $(vdso32.so-y:%=vdso32-%.so)

CPPFLAGS_vdso32.lds = $(CPPFLAGS_vdso.lds)
VDSO_LDFLAGS_vdso32.lds = -m32 -Wl,-soname=linux-gate.so.1

# This makes sure the $(obj) subdirectory exists even though vdso32/
# is not a kbuild sub-make subdirectory.
override obj-dirs = $(dir $(obj)) $(obj)/vdso32/

targets += vdso32/vdso32.lds
targets += $(vdso32-images) $(vdso32-images:=.dbg)
targets += vdso32/note.o $(vdso32.so-y:%=vdso32/%.o)

extra-y	+= $(vdso32-images)

$(obj)/vdso32.o: $(vdso32-images:%=$(obj)/%)

KBUILD_AFLAGS_32 := $(filter-out -m64,$(KBUILD_AFLAGS))
$(vdso32-images:%=$(obj)/%.dbg): KBUILD_AFLAGS = $(KBUILD_AFLAGS_32)
$(vdso32-images:%=$(obj)/%.dbg): asflags-$(CONFIG_X86_64) += -m32

$(vdso32-images:%=$(obj)/%.dbg): $(obj)/vdso32-%.so.dbg: FORCE \
				 $(obj)/vdso32/vdso32.lds \
				 $(obj)/vdso32/note.o \
				 $(obj)/vdso32/%.o
	$(call if_changed,vdso)

# Make vdso32-*-syms.lds from each image, and then make sure they match.
# The only difference should be that some do not define VDSO32_SYSENTER_RETURN.

targets += vdso32-syms.lds $(vdso32.so-y:%=vdso32-%-syms.lds)

quiet_cmd_vdso32sym = VDSOSYM $@
define cmd_vdso32sym
	if LC_ALL=C sort -u $(filter-out FORCE,$^) > $(@D)/.tmp_$(@F) && \
	   $(foreach H,$(filter-out FORCE,$^),\
		     if grep -q VDSO32_SYSENTER_RETURN $H; \
		     then diff -u $(@D)/.tmp_$(@F) $H; \
		     else sed /VDSO32_SYSENTER_RETURN/d $(@D)/.tmp_$(@F) | \
			  diff -u - $H; fi &&) : ;\
	then mv -f $(@D)/.tmp_$(@F) $@; \
	else rm -f $(@D)/.tmp_$(@F); exit 1; \
	fi
endef

$(obj)/vdso32-syms.lds: $(vdso32.so-y:%=$(obj)/vdso32-%-syms.lds) FORCE
	$(call if_changed,vdso32sym)

#
# The DSO images are built using a special linker script.
#
quiet_cmd_vdso = VDSO    $@
      cmd_vdso = $(CC) -nostdlib -o $@ \
		       $(VDSO_LDFLAGS) $(VDSO_LDFLAGS_$(filter %.lds,$(^F))) \
		       -Wl,-T,$(filter %.lds,$^) $(filter %.o,$^) && \
		 sh $(srctree)/$(src)/checkundef.sh '$(NM)' '$@'

VDSO_LDFLAGS = -fPIC -shared $(call cc-ldoption, -Wl$(comma)--hash-style=sysv)
GCOV_PROFILE := n

#
# Install the unstripped copy of vdso*.so listed in $(vdso-install-y).
#
quiet_cmd_vdso_install = INSTALL $@
      cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/$@
$(vdso-install-y): %.so: $(obj)/%.so.dbg FORCE
	@mkdir -p $(MODLIB)/vdso
	$(call cmd,vdso_install)

PHONY += vdso_install $(vdso-install-y)
vdso_install: $(vdso-install-y)

clean-files := vdso32-syscall* vdso32-sysenter* vdso32-int80*