========
[root@localhost ~]# cat vdso_test.c
int main() {
struct timespec tv_start, tv_end;
struct timeval tv_tmp;
int i;
int count = 1 * 1000 * 10000;
long long diff;
clock_gettime(0, &tv_start);
for (i = 0; i < count; i++)
gettimeofday(&tv_tmp, NULL);
clock_gettime(0, &tv_end);
diff = (long long)(tv_end.tv_sec -
tv_start.tv_sec)*(1*1000*1000*1000);
diff += (tv_end.tv_nsec - tv_start.tv_nsec);
printf("Start sec: %d\n", tv_start.tv_sec);
printf("End sec : %d\n", tv_end.tv_sec);
printf("%d cycles in %lld ns = %f ns/cycle\n", count, diff,
(double)diff / (double)count);
return 0;
}
[root@localhost ~]# cc vdso_test.c -o t32_without_fix -m32 -lrt
[root@localhost ~]# ./t32_without_fix
Start sec: 1502396130
End sec : 1502396140
10000000 cycles in 9565148528 ns = 956.514853 ns/cycle
[root@localhost ~]# cc vdso_test.c -o t32_with_fix -m32 ./vdso32.so.dbg
[root@localhost ~]# ./t32_with_fix
Start sec: 1502396168
End sec : 1502396169
10000000 cycles in 798141262 ns = 79.814126 ns/cycle
[root@localhost ~]# cc vdso_test.c -o t64_without_fix -m64 -lrt
[root@localhost ~]# ./t64_without_fix
Start sec: 1502396208
End sec : 1502396218
10000000 cycles in 9846091800 ns = 984.609180 ns/cycle
[root@localhost ~]# cc vdso_test.c -o t64_with_fix -m64 ./vdso64.so.dbg
[root@localhost ~]# ./t64_with_fix
Start sec: 1502396257
End sec : 1502396257
10000000 cycles in 380984048 ns = 38.098405 ns/cycle
V1 to V2 Changes:
=================
Added hot patching code to switch the read stick instruction to read
tick instruction based on the hardware.
V2 to V3 Changes:
=================
Merged latest changes from sparc-next and moved the initialization
of clocksource_tick.archdata.vclock_mode to time_init_early. Disabled
queued spinlock and rwlock configuration when simulating 32-bit config
to compile 32-bit VDSO.
V3 to V4 Changes:
=================
Hardcoded the page size as 8192 in linker script for both 64-bit and
32-bit binaries. Removed unused variables in vdso2c.h. Added -mv8plus flag to
Makefile to prevent the generation of relocation entries for __lshrdi3 in 32-bit
vdso binary.
Signed-off-by: Nick Alcock <nick.alcock@oracle.com>
Signed-off-by: Nagarathnam Muthusamy <nagarathnam.muthusamy@oracle.com>
Reviewed-by: Shannon Nelson <shannon.nelson@oracle.com>
---
arch/sparc/Kbuild | 1 +
arch/sparc/Kconfig | 2 +
arch/sparc/Makefile | 4 +
arch/sparc/include/asm/clocksource.h | 17 ++
arch/sparc/include/asm/elf_64.h | 14 ++
arch/sparc/include/asm/mmu_64.h | 1 +
arch/sparc/include/asm/processor_64.h | 8 +
arch/sparc/include/asm/vdso.h | 24 +++
arch/sparc/include/asm/vvar.h | 74 +++++++++
arch/sparc/include/uapi/asm/auxvec.h | 4 +
arch/sparc/kernel/Makefile | 1 +
arch/sparc/kernel/time_64.c | 11 +-
arch/sparc/kernel/vdso.c | 70 ++++++++
arch/sparc/vdso/.gitignore | 3 +
arch/sparc/vdso/Makefile | 149 +++++++++++++++++
arch/sparc/vdso/vclock_gettime.c | 264 ++++++++++++++++++++++++++++++
arch/sparc/vdso/vdso-layout.lds.S | 104 ++++++++++++
arch/sparc/vdso/vdso-note.S | 12 ++
arch/sparc/vdso/vdso.lds.S | 25 +++
arch/sparc/vdso/vdso2c.c | 234 +++++++++++++++++++++++++++
arch/sparc/vdso/vdso2c.h | 143 ++++++++++++++++
arch/sparc/vdso/vdso32/.gitignore | 1 +
arch/sparc/vdso/vdso32/vclock_gettime.c | 26 +++
arch/sparc/vdso/vdso32/vdso-note.S | 12 ++
arch/sparc/vdso/vdso32/vdso32.lds.S | 24 +++
arch/sparc/vdso/vma.c | 268 +++++++++++++++++++++++++++++++
26 files changed, 1494 insertions(+), 2 deletions(-)
create mode 100644 arch/sparc/include/asm/clocksource.h
create mode 100644 arch/sparc/include/asm/vdso.h
create mode 100644 arch/sparc/include/asm/vvar.h
create mode 100644 arch/sparc/kernel/vdso.c
create mode 100644 arch/sparc/vdso/.gitignore
create mode 100644 arch/sparc/vdso/Makefile
create mode 100644 arch/sparc/vdso/vclock_gettime.c
create mode 100644 arch/sparc/vdso/vdso-layout.lds.S
create mode 100644 arch/sparc/vdso/vdso-note.S
create mode 100644 arch/sparc/vdso/vdso.lds.S
create mode 100644 arch/sparc/vdso/vdso2c.c
create mode 100644 arch/sparc/vdso/vdso2c.h
create mode 100644 arch/sparc/vdso/vdso32/.gitignore
create mode 100644 arch/sparc/vdso/vdso32/vclock_gettime.c
create mode 100644 arch/sparc/vdso/vdso32/vdso-note.S
create mode 100644 arch/sparc/vdso/vdso32/vdso32.lds.S
create mode 100644 arch/sparc/vdso/vma.c
@@ -7,3 +7,4 @@ obj-y += mm/
obj-y += math-emu/
obj-y += net/
obj-y += crypto/
+obj-$(CONFIG_SPARC64) += vdso/
@@ -85,6 +85,8 @@ config SPARC64
select HAVE_REGS_AND_STACK_ACCESS_API
select ARCH_USE_QUEUED_RWLOCKS
select ARCH_USE_QUEUED_SPINLOCKS
+ select GENERIC_TIME_VSYSCALL
+ select ARCH_CLOCKSOURCE_DATA
config ARCH_DEFCONFIG
string
@@ -80,6 +80,10 @@ install:
archclean:
$(Q)$(MAKE) $(clean)=$(boot)
+PHONY += vdso_install
+vdso_install:
+ $(Q)$(MAKE) $(build)=arch/sparc/vdso $@
+
# This is the image used for packaging
KBUILD_IMAGE := $(boot)/zImage
new file mode 100644
@@ -0,0 +1,17 @@
+/*
+ * Copyright (c) 2017 Oracle and/or its affiliates. All rights reserved.
+ */
+
+#ifndef _ASM_SPARC_CLOCKSOURCE_H
+#define _ASM_SPARC_CLOCKSOURCE_H
+
+/* VDSO clocksources */
+#define VCLOCK_NONE 0 /* Nothing userspace can do. */
+#define VCLOCK_TICK 1 /* Use %tick. */
+#define VCLOCK_STICK 2 /* Use %stick. */
+
+struct arch_clocksource_data {
+ int vclock_mode;
+};
+
+#endif /* _ASM_SPARC_CLOCKSOURCE_H */
@@ -210,4 +210,18 @@
(current->personality & (~PER_MASK))); \
} while (0)
+extern unsigned int vdso_enabled;
+
+#define ARCH_DLINFO \
+do { \
+ if (vdso_enabled) \
+ NEW_AUX_ENT(AT_SYSINFO_EHDR, \
+ (unsigned long)current->mm->context.vdso); \
+} while (0)
+
+struct linux_binprm;
+
+#define ARCH_HAS_SETUP_ADDITIONAL_PAGES 1
+extern int arch_setup_additional_pages(struct linux_binprm *bprm,
+ int uses_interp);
#endif /* !(__ASM_SPARC64_ELF_H) */
@@ -96,6 +96,7 @@ struct tsb_config {
unsigned long thp_pte_count;
struct tsb_config tsb_block[MM_NUM_TSBS];
struct hv_tsb_descr tsb_descr[MM_NUM_TSBS];
+ void *vdso;
} mm_context_t;
#endif /* !__ASSEMBLY__ */
@@ -199,6 +199,13 @@ struct thread_struct {
* To make a long story short, we are trying to yield the current cpu
* strand during busy loops.
*/
+#ifdef BUILD_VDSO
+#define cpu_relax() asm volatile("\n99:\n\t" \
+ "rd %%ccr, %%g0\n\t" \
+ "rd %%ccr, %%g0\n\t" \
+ "rd %%ccr, %%g0\n\t" \
+ ::: "memory")
+#else /* ! BUILD_VDSO */
#define cpu_relax() asm volatile("\n99:\n\t" \
"rd %%ccr, %%g0\n\t" \
"rd %%ccr, %%g0\n\t" \
@@ -210,6 +217,7 @@ struct thread_struct {
"nop\n\t" \
".previous" \
::: "memory")
+#endif
/* Prefetch support. This is tuned for UltraSPARC-III and later.
* UltraSPARC-I will treat these as nops, and UltraSPARC-II has
new file mode 100644
@@ -0,0 +1,24 @@
+/*
+ * Copyright (c) 2017 Oracle and/or its affiliates. All rights reserved.
+ */
+
+#ifndef _ASM_SPARC_VDSO_H
+#define _ASM_SPARC_VDSO_H
+
+struct vdso_image {
+ void *data;
+ unsigned long size; /* Always a multiple of PAGE_SIZE */
+ long sym_vvar_start; /* Negative offset to the vvar area */
+ long sym_vread_tick; /* Start of vread_tick section */
+ long sym_vread_tick_patch_start; /* Start of tick read */
+ long sym_vread_tick_patch_end; /* End of tick read */
+};
+
+#ifdef CONFIG_SPARC64
+extern const struct vdso_image vdso_image_64_builtin;
+#endif
+#ifdef CONFIG_COMPAT
+extern const struct vdso_image vdso_image_32_builtin;
+#endif
+
+#endif /* _ASM_SPARC_VDSO_H */
new file mode 100644
@@ -0,0 +1,74 @@
+/*
+ * Copyright (c) 2017 Oracle and/or its affiliates. All rights reserved.
+ */
+
+#ifndef _ASM_SPARC_VVAR_DATA_H
+#define _ASM_SPARC_VVAR_DATA_H
+
+#include <asm/clocksource.h>
+#include <linux/seqlock.h>
+#include <linux/time.h>
+#include <linux/types.h>
+
+struct vvar_data {
+ unsigned int seq;
+
+ int vclock_mode;
+ struct { /* extract of a clocksource struct */
+ u64 cycle_last;
+ u64 mask;
+ int mult;
+ int shift;
+ } clock;
+ /* open coded 'struct timespec' */
+ u64 wall_time_sec;
+ u64 wall_time_snsec;
+ u64 monotonic_time_snsec;
+ u64 monotonic_time_sec;
+ u64 monotonic_time_coarse_sec;
+ u64 monotonic_time_coarse_nsec;
+ u64 wall_time_coarse_sec;
+ u64 wall_time_coarse_nsec;
+
+ int tz_minuteswest;
+ int tz_dsttime;
+};
+
+extern struct vvar_data *vvar_data;
+extern int vdso_fix_stick;
+
+static inline unsigned int vvar_read_begin(const struct vvar_data *s)
+{
+ unsigned int ret;
+
+repeat:
+ ret = READ_ONCE(s->seq);
+ if (unlikely(ret & 1)) {
+ cpu_relax();
+ goto repeat;
+ }
+ smp_rmb(); /* Finish all reads before we return seq */
+ return ret;
+}
+
+static inline int vvar_read_retry(const struct vvar_data *s,
+ unsigned int start)
+{
+ smp_rmb(); /* Finish all reads before checking the value of seq */
+ return unlikely(s->seq != start);
+}
+
+static inline void vvar_write_begin(struct vvar_data *s)
+{
+ ++s->seq;
+ smp_wmb(); /* Makes sure that increment of seq is reflected */
+}
+
+static inline void vvar_write_end(struct vvar_data *s)
+{
+ smp_wmb(); /* Makes the value of seq current before we increment */
+ ++s->seq;
+}
+
+
+#endif /* _ASM_SPARC_VVAR_DATA_H */
@@ -1,4 +1,8 @@
#ifndef __ASMSPARC_AUXVEC_H
#define __ASMSPARC_AUXVEC_H
+#define AT_SYSINFO_EHDR 33
+
+#define AT_VECTOR_SIZE_ARCH 1
+
#endif /* !(__ASMSPARC_AUXVEC_H) */
@@ -42,6 +42,7 @@ obj-$(CONFIG_SPARC32) += systbls_32.o
obj-y += time_$(BITS).o
obj-$(CONFIG_SPARC32) += windows.o
obj-y += cpu.o
+obj-$(CONFIG_SPARC64) += vdso.o
obj-$(CONFIG_SPARC32) += devices.o
obj-y += ptrace_$(BITS).o
obj-y += unaligned_$(BITS).o
@@ -53,6 +53,8 @@
DEFINE_SPINLOCK(rtc_lock);
+unsigned int __read_mostly vdso_fix_stick;
+
#ifdef CONFIG_SMP
unsigned long profile_pc(struct pt_regs *regs)
{
@@ -830,12 +832,17 @@ static void init_tick_ops(struct sparc64_tick_ops *ops)
void __init time_init_early(void)
{
if (tlb_type == spitfire) {
- if (is_hummingbird())
+ if (is_hummingbird()) {
init_tick_ops(&hbtick_operations);
- else
+ clocksource_tick.archdata.vclock_mode = VCLOCK_NONE;
+ } else {
init_tick_ops(&tick_operations);
+ clocksource_tick.archdata.vclock_mode = VCLOCK_TICK;
+ vdso_fix_stick = 1;
+ }
} else {
init_tick_ops(&stick_operations);
+ clocksource_tick.archdata.vclock_mode = VCLOCK_STICK;
}
}
new file mode 100644
@@ -0,0 +1,70 @@
+/*
+ * Copyright (C) 2001 Andrea Arcangeli <andrea@suse.de> SuSE
+ * Copyright 2003 Andi Kleen, SuSE Labs.
+ *
+ * Thanks to hpa@transmeta.com for some useful hint.
+ * Special thanks to Ingo Molnar for his early experience with
+ * a different vsyscall implementation for Linux/IA32 and for the name.
+ */
+
+#include <linux/seqlock.h>
+#include <linux/time.h>
+#include <linux/timekeeper_internal.h>
+
+#include <asm/vvar.h>
+
+void update_vsyscall_tz(void)
+{
+ if (unlikely(vvar_data == NULL))
+ return;
+
+ vvar_data->tz_minuteswest = sys_tz.tz_minuteswest;
+ vvar_data->tz_dsttime = sys_tz.tz_dsttime;
+}
+
+void update_vsyscall(struct timekeeper *tk)
+{
+ struct vvar_data *vdata = vvar_data;
+
+ if (unlikely(vdata == NULL))
+ return;
+
+ vvar_write_begin(vdata);
+ vdata->vclock_mode = tk->tkr_mono.clock->archdata.vclock_mode;
+ vdata->clock.cycle_last = tk->tkr_mono.cycle_last;
+ vdata->clock.mask = tk->tkr_mono.mask;
+ vdata->clock.mult = tk->tkr_mono.mult;
+ vdata->clock.shift = tk->tkr_mono.shift;
+
+ vdata->wall_time_sec = tk->xtime_sec;
+ vdata->wall_time_snsec = tk->tkr_mono.xtime_nsec;
+
+ vdata->monotonic_time_sec = tk->xtime_sec +
+ tk->wall_to_monotonic.tv_sec;
+ vdata->monotonic_time_snsec = tk->tkr_mono.xtime_nsec +
+ (tk->wall_to_monotonic.tv_nsec <<
+ tk->tkr_mono.shift);
+
+ while (vdata->monotonic_time_snsec >=
+ (((u64)NSEC_PER_SEC) << tk->tkr_mono.shift)) {
+ vdata->monotonic_time_snsec -=
+ ((u64)NSEC_PER_SEC) << tk->tkr_mono.shift;
+ vdata->monotonic_time_sec++;
+ }
+
+ vdata->wall_time_coarse_sec = tk->xtime_sec;
+ vdata->wall_time_coarse_nsec =
+ (long)(tk->tkr_mono.xtime_nsec >> tk->tkr_mono.shift);
+
+ vdata->monotonic_time_coarse_sec =
+ vdata->wall_time_coarse_sec + tk->wall_to_monotonic.tv_sec;
+ vdata->monotonic_time_coarse_nsec =
+ vdata->wall_time_coarse_nsec + tk->wall_to_monotonic.tv_nsec;
+
+ while (vdata->monotonic_time_coarse_nsec >= NSEC_PER_SEC) {
+ vdata->monotonic_time_coarse_nsec -= NSEC_PER_SEC;
+ vdata->monotonic_time_coarse_sec++;
+ }
+
+ vvar_write_end(vdata);
+}
new file mode 100644
@@ -0,0 +1,3 @@
+vdso.lds
+vdso-image-*.c
+vdso2c
new file mode 100644
@@ -0,0 +1,149 @@
+#
+# Building vDSO images for sparc.
+#
+
+KBUILD_CFLAGS += $(DISABLE_LTO)
+
+VDSO64-$(CONFIG_SPARC64) := y
+VDSOCOMPAT-$(CONFIG_COMPAT) := y
+
+# files to link into the vdso
+vobjs-y := vdso-note.o vclock_gettime.o
+
+# files to link into kernel
+obj-y += vma.o
+
+# vDSO images to build
+vdso_img-$(VDSO64-y) += 64
+vdso_img-$(VDSOCOMPAT-y) += 32
+
+vobjs := $(foreach F,$(vobjs-y),$(obj)/$F)
+
+$(obj)/vdso.o: $(obj)/vdso.so
+
+targets += vdso.lds $(vobjs-y)
+
+# Build the vDSO image C files and link them in.
+vdso_img_objs := $(vdso_img-y:%=vdso-image-%.o)
+vdso_img_cfiles := $(vdso_img-y:%=vdso-image-%.c)
+vdso_img_sodbg := $(vdso_img-y:%=vdso%.so.dbg)
+obj-y += $(vdso_img_objs)
+targets += $(vdso_img_cfiles)
+targets += $(vdso_img_sodbg)
+.SECONDARY: $(vdso_img-y:%=$(obj)/vdso-image-%.c) \
+ $(vdso_img-y:%=$(obj)/vdso%.so)
+
+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=8192 -Wl,-z,common-page-size=8192 \
+ $(DISABLE_LTO)
+
+$(obj)/vdso64.so.dbg: $(src)/vdso.lds $(vobjs) FORCE
+ $(call if_changed,vdso)
+
+HOST_EXTRACFLAGS += -I$(srctree)/tools/include
+hostprogs-y += vdso2c
+
+quiet_cmd_vdso2c = VDSO2C $@
+define cmd_vdso2c
+ $(obj)/vdso2c $< $(<:%.dbg=%) $@
+endef
+
+$(obj)/vdso-image-%.c: $(obj)/vdso%.so.dbg $(obj)/vdso%.so $(obj)/vdso2c FORCE
+ $(call if_changed,vdso2c)
+
+#
+# Don't omit frame pointers for ease of userspace debugging, but do
+# optimize sibling calls.
+#
+CFL := $(PROFILING) -mcmodel=medlow -fPIC -O2 -fasynchronous-unwind-tables \
+ -m64 -ffixed-g2 -ffixed-g3 -fcall-used-g4 -fcall-used-g5 -ffixed-g6 \
+ -ffixed-g7 $(filter -g%,$(KBUILD_CFLAGS)) \
+ $(call cc-option, -fno-stack-protector) -fno-omit-frame-pointer \
+ -foptimize-sibling-calls -DBUILD_VDSO
+
+$(vobjs): KBUILD_CFLAGS += $(CFL)
+
+#
+# vDSO code runs in userspace and -pg doesn't help with profiling anyway.
+#
+CFLAGS_REMOVE_vdso-note.o = -pg
+CFLAGS_REMOVE_vclock_gettime.o = -pg
+
+$(obj)/%.so: OBJCOPYFLAGS := -S
+$(obj)/%.so: $(obj)/%.so.dbg
+ $(call if_changed,objcopy)
+
+CPPFLAGS_vdso32.lds = $(CPPFLAGS_vdso.lds)
+VDSO_LDFLAGS_vdso32.lds = -m32 -Wl,-m,elf32_sparc,-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/vdso-note.o
+targets += vdso32/vclock_gettime.o
+
+KBUILD_AFLAGS_32 := $(filter-out -m64,$(KBUILD_AFLAGS)) -DBUILD_VDSO
+$(obj)/vdso32.so.dbg: KBUILD_AFLAGS = $(KBUILD_AFLAGS_32)
+$(obj)/vdso32.so.dbg: asflags-$(CONFIG_SPARC64) += -m32
+
+KBUILD_CFLAGS_32 := $(filter-out -m64,$(KBUILD_CFLAGS))
+KBUILD_CFLAGS_32 := $(filter-out -mcmodel=medlow,$(KBUILD_CFLAGS_32))
+KBUILD_CFLAGS_32 := $(filter-out -fno-pic,$(KBUILD_CFLAGS_32))
+KBUILD_CFLAGS_32 := $(filter-out $(GCC_PLUGINS_CFLAGS),$(KBUILD_CFLAGS_32))
+KBUILD_CFLAGS_32 += -m32 -msoft-float -fpic -mno-app-regs -ffixed-g7
+KBUILD_CFLAGS_32 += $(call cc-option, -fno-stack-protector)
+KBUILD_CFLAGS_32 += $(call cc-option, -foptimize-sibling-calls)
+KBUILD_CFLAGS_32 += -fno-omit-frame-pointer
+KBUILD_CFLAGS_32 += -DDISABLE_BRANCH_PROFILING
+KBUILD_CFLAGS_32 += -mv8plus
+$(obj)/vdso32.so.dbg: KBUILD_CFLAGS = $(KBUILD_CFLAGS_32)
+
+$(obj)/vdso32.so.dbg: FORCE \
+ $(obj)/vdso32/vdso32.lds \
+ $(obj)/vdso32/vclock_gettime.o \
+ $(obj)/vdso32/vdso-note.o
+ $(call if_changed,vdso)
+
+#
+# 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,$^) $(filter %.o,$^)
+
+VDSO_LDFLAGS = -fPIC -shared $(call cc-ldoption, -Wl$(comma)--hash-style=sysv) \
+ $(call cc-ldoption, -Wl$(comma)--build-id) -Wl,-Bsymbolic
+GCOV_PROFILE := n
+
+#
+# Install the unstripped copies of vdso*.so. If our toolchain supports
+# build-id, install .build-id links as well.
+#
+quiet_cmd_vdso_install = INSTALL $(@:install_%=%)
+define cmd_vdso_install
+ cp $< "$(MODLIB)/vdso/$(@:install_%=%)"; \
+ if readelf -n $< |grep -q 'Build ID'; then \
+ buildid=`readelf -n $< |grep 'Build ID' |sed -e 's/^.*Build ID: \(.*\)$$/\1/'`; \
+ first=`echo $$buildid | cut -b-2`; \
+ last=`echo $$buildid | cut -b3-`; \
+ mkdir -p "$(MODLIB)/vdso/.build-id/$$first"; \
+ ln -sf "../../$(@:install_%=%)" "$(MODLIB)/vdso/.build-id/$$first/$$last.debug"; \
+ fi
+endef
+
+vdso_img_insttargets := $(vdso_img_sodbg:%.dbg=install_%)
+
+$(MODLIB)/vdso: FORCE
+ @mkdir -p $(MODLIB)/vdso
+
+$(vdso_img_insttargets): install_%: $(obj)/%.dbg $(MODLIB)/vdso FORCE
+ $(call cmd,vdso_install)
+
+PHONY += vdso_install $(vdso_img_insttargets)
+vdso_install: $(vdso_img_insttargets) FORCE
new file mode 100644
@@ -0,0 +1,264 @@
+/*
+ * Copyright 2006 Andi Kleen, SUSE Labs.
+ * Subject to the GNU Public License, v.2
+ *
+ * Fast user context implementation of clock_gettime, gettimeofday, and time.
+ *
+ * The code should have no internal unresolved relocations.
+ * Check with readelf after changing.
+ * Also alternative() doesn't work.
+ */
+/*
+ * Copyright (c) 2017 Oracle and/or its affiliates. All rights reserved.
+ */
+
+/* Disable profiling for userspace code: */
+#ifndef DISABLE_BRANCH_PROFILING
+#define DISABLE_BRANCH_PROFILING
+#endif
+
+#include <linux/kernel.h>
+#include <linux/time.h>
+#include <linux/string.h>
+#include <asm/io.h>
+#include <asm/unistd.h>
+#include <asm/timex.h>
+#include <asm/clocksource.h>
+#include <asm/vvar.h>
+
+#undef TICK_PRIV_BIT
+#ifdef CONFIG_SPARC64
+#define TICK_PRIV_BIT (1UL << 63)
+#else
+#define TICK_PRIV_BIT (1ULL << 63)
+#endif
+
+#define SYSCALL_STRING \
+ "ta 0x6d;" \
+ "sub %%g0, %%o0, %%o0;" \
+
+#define SYSCALL_CLOBBERS \
+ "f0", "f1", "f2", "f3", "f4", "f5", "f6", "f7", \
+ "f8", "f9", "f10", "f11", "f12", "f13", "f14", "f15", \
+ "f16", "f17", "f18", "f19", "f20", "f21", "f22", "f23", \
+ "f24", "f25", "f26", "f27", "f28", "f29", "f30", "f31", \
+ "f32", "f34", "f36", "f38", "f40", "f42", "f44", "f46", \
+ "f48", "f50", "f52", "f54", "f56", "f58", "f60", "f62", \
+ "cc", "memory"
+
+/*
+ * Compute the vvar page's address in the process address space, and return it
+ * as a pointer to the vvar_data.
+ */
+static notrace noinline struct vvar_data *
+get_vvar_data(void)
+{
+ unsigned long ret;
+
+ /*
+ * vdso data page is the first vDSO page so grab the return address
+ * and move up a page to get to the data page.
+ */
+ ret = (unsigned long)__builtin_return_address(0);
+ ret &= ~(8192 - 1);
+ ret -= 8192;
+
+ return (struct vvar_data *) ret;
+}
+
+static notrace long
+vdso_fallback_gettime(long clock, struct timespec *ts)
+{
+ register long num __asm__("g1") = __NR_clock_gettime;
+ register long o0 __asm__("o0") = clock;
+ register long o1 __asm__("o1") = (long) ts;
+
+ __asm__ __volatile__(SYSCALL_STRING : "=r" (o0) : "r" (num),
+ "0" (o0), "r" (o1) : SYSCALL_CLOBBERS);
+ return o0;
+}
+
+static notrace __always_inline long
+vdso_fallback_gettimeofday(struct timeval *tv, struct timezone *tz)
+{
+ register long num __asm__("g1") = __NR_gettimeofday;
+ register long o0 __asm__("o0") = (long) tv;
+ register long o1 __asm__("o1") = (long) tz;
+
+ __asm__ __volatile__(SYSCALL_STRING : "=r" (o0) : "r" (num),
+ "0" (o0), "r" (o1) : SYSCALL_CLOBBERS);
+ return o0;
+}
+
+#ifdef CONFIG_SPARC64
+static notrace noinline u64
+vread_tick(void) {
+ u64 ret;
+
+ __asm__ __volatile__("rd %%asr24, %0 \n"
+ ".section .vread_tick_patch, \"ax\" \n"
+ "rd %%tick, %0 \n"
+ ".previous \n"
+ : "=&r" (ret));
+ return ret & ~TICK_PRIV_BIT;
+}
+#else
+static notrace noinline u64
+vread_tick(void)
+{
+ unsigned int lo, hi;
+
+ __asm__ __volatile__("rd %%asr24, %%g1\n\t"
+ "srlx %%g1, 32, %1\n\t"
+ "srl %%g1, 0, %0\n"
+ ".section .vread_tick_patch, \"ax\" \n"
+ "rd %%tick, %%g1\n"
+ ".previous \n"
+ : "=&r" (lo), "=&r" (hi)
+ :
+ : "g1");
+ return lo | ((u64)hi << 32);
+}
+#endif
+
+static notrace inline u64
+vgetsns(struct vvar_data *vvar)
+{
+ u64 v;
+ u64 cycles;
+
+ cycles = vread_tick();
+ v = (cycles - vvar->clock.cycle_last) & vvar->clock.mask;
+ return v * vvar->clock.mult;
+}
+
+static notrace noinline int
+do_realtime(struct vvar_data *vvar, struct timespec *ts)
+{
+ unsigned long seq;
+ u64 ns;
+
+ ts->tv_nsec = 0;
+ do {
+ seq = vvar_read_begin(vvar);
+ ts->tv_sec = vvar->wall_time_sec;
+ ns = vvar->wall_time_snsec;
+ ns += vgetsns(vvar);
+ ns >>= vvar->clock.shift;
+ } while (unlikely(vvar_read_retry(vvar, seq)));
+
+ timespec_add_ns(ts, ns);
+
+ return 0;
+}
+
+static notrace noinline int
+do_monotonic(struct vvar_data *vvar, struct timespec *ts)
+{
+ unsigned long seq;
+ u64 ns;
+
+ ts->tv_nsec = 0;
+ do {
+ seq = vvar_read_begin(vvar);
+ ts->tv_sec = vvar->monotonic_time_sec;
+ ns = vvar->monotonic_time_snsec;
+ ns += vgetsns(vvar);
+ ns >>= vvar->clock.shift;
+ } while (unlikely(vvar_read_retry(vvar, seq)));
+
+ timespec_add_ns(ts, ns);
+
+ return 0;
+}
+
+static notrace noinline int
+do_realtime_coarse(struct vvar_data *vvar, struct timespec *ts)
+{
+ unsigned long seq;
+
+ do {
+ seq = vvar_read_begin(vvar);
+ ts->tv_sec = vvar->wall_time_coarse_sec;
+ ts->tv_nsec = vvar->wall_time_coarse_nsec;
+ } while (unlikely(vvar_read_retry(vvar, seq)));
+ return 0;
+}
+
+static notrace noinline int
+do_monotonic_coarse(struct vvar_data *vvar, struct timespec *ts)
+{
+ unsigned long seq;
+
+ do {
+ seq = vvar_read_begin(vvar);
+ ts->tv_sec = vvar->monotonic_time_coarse_sec;
+ ts->tv_nsec = vvar->monotonic_time_coarse_nsec;
+ } while (unlikely(vvar_read_retry(vvar, seq)));
+
+ return 0;
+}
+
+notrace int
+__vdso_clock_gettime(clockid_t clock, struct timespec *ts)
+{
+ struct vvar_data *vvd = get_vvar_data();
+
+ switch (clock) {
+ case CLOCK_REALTIME:
+ if (unlikely(vvd->vclock_mode == VCLOCK_NONE))
+ break;
+ return do_realtime(vvd, ts);
+ case CLOCK_MONOTONIC:
+ if (unlikely(vvd->vclock_mode == VCLOCK_NONE))
+ break;
+ return do_monotonic(vvd, ts);
+ case CLOCK_REALTIME_COARSE:
+ return do_realtime_coarse(vvd, ts);
+ case CLOCK_MONOTONIC_COARSE:
+ return do_monotonic_coarse(vvd, ts);
+ }
+ /*
+ * Unknown clock ID ? Fall back to the syscall.
+ */
+ return vdso_fallback_gettime(clock, ts);
+}
+int
+clock_gettime(clockid_t, struct timespec *)
+ __attribute__((weak, alias("__vdso_clock_gettime")));
+
+notrace int
+__vdso_gettimeofday(struct timeval *tv, struct timezone *tz)
+{
+ struct vvar_data *vvd = get_vvar_data();
+
+ if (likely(vvd->vclock_mode != VCLOCK_NONE)) {
+ if (likely(tv != NULL)) {
+ union tstv_t {
+ struct timespec ts;
+ struct timeval tv;
+ } *tstv = (union tstv_t *) tv;
+ do_realtime(vvd, &tstv->ts);
+ /*
+ * Assign before dividing to ensure that the division is
+ * done in the type of tv_usec, not tv_nsec.
+ *
+ * There cannot be > 1 billion usec in a second:
+ * do_realtime() has already distributed such overflow
+ * into tv_sec. So we can assign it to an int safely.
+ */
+ tstv->tv.tv_usec = tstv->ts.tv_nsec;
+ tstv->tv.tv_usec /= 1000;
+ }
+ if (unlikely(tz != NULL)) {
+ /* Avoid memcpy. Some old compilers fail to inline it */
+ tz->tz_minuteswest = vvd->tz_minuteswest;
+ tz->tz_dsttime = vvd->tz_dsttime;
+ }
+ return 0;
+ }
+ return vdso_fallback_gettimeofday(tv, tz);
+}
+int
+gettimeofday(struct timeval *, struct timezone *)
+ __attribute__((weak, alias("__vdso_gettimeofday")));
new file mode 100644
@@ -0,0 +1,104 @@
+/*
+ * Linker script for vDSO. This is an ELF shared object prelinked to
+ * its virtual address, and with only one read-only segment.
+ * This script controls its layout.
+ */
+
+#if defined(BUILD_VDSO64)
+# define SHDR_SIZE 64
+#elif defined(BUILD_VDSO32)
+# define SHDR_SIZE 40
+#else
+# error unknown VDSO target
+#endif
+
+#define NUM_FAKE_SHDRS 7
+
+SECTIONS
+{
+ /*
+ * User/kernel shared data is before the vDSO. This may be a little
+ * uglier than putting it after the vDSO, but it avoids issues with
+ * non-allocatable things that dangle past the end of the PT_LOAD
+ * segment. Page size is 8192 for both 64-bit and 32-bit vdso binaries
+ */
+
+ vvar_start = . -8192;
+ vvar_data = vvar_start;
+
+ . = SIZEOF_HEADERS;
+
+ .hash : { *(.hash) } :text
+ .gnu.hash : { *(.gnu.hash) }
+ .dynsym : { *(.dynsym) }
+ .dynstr : { *(.dynstr) }
+ .gnu.version : { *(.gnu.version) }
+ .gnu.version_d : { *(.gnu.version_d) }
+ .gnu.version_r : { *(.gnu.version_r) }
+
+ .dynamic : { *(.dynamic) } :text :dynamic
+
+ .rodata : {
+ *(.rodata*)
+ *(.data*)
+ *(.sdata*)
+ *(.got.plt) *(.got)
+ *(.gnu.linkonce.d.*)
+ *(.bss*)
+ *(.dynbss*)
+ *(.gnu.linkonce.b.*)
+
+ /*
+ * Ideally this would live in a C file: kept in here for
+ * compatibility with x86-64.
+ */
+ VDSO_FAKE_SECTION_TABLE_START = .;
+ . = . + NUM_FAKE_SHDRS * SHDR_SIZE;
+ VDSO_FAKE_SECTION_TABLE_END = .;
+ } :text
+
+ .fake_shstrtab : { *(.fake_shstrtab) } :text
+
+
+ .note : { *(.note.*) } :text :note
+
+ .eh_frame_hdr : { *(.eh_frame_hdr) } :text :eh_frame_hdr
+ .eh_frame : { KEEP (*(.eh_frame)) } :text
+
+
+ /*
+ * Text is well-separated from actual data: there's plenty of
+ * stuff that isn't used at runtime in between.
+ */
+
+ .text : { *(.text*) } :text =0x90909090,
+
+ .vread_tick_patch : {
+ vread_tick_patch_start = .;
+ *(.vread_tick_patch)
+ vread_tick_patch_end = .;
+ }
+
+ /DISCARD/ : {
+ *(.discard)
+ *(.discard.*)
+ *(__bug_table)
+ }
+}
+
+/*
+ * Very old versions of ld do not recognize this name token; use the constant.
+ */
+#define PT_GNU_EH_FRAME 0x6474e550
+
+/*
+ * We must supply the ELF program headers explicitly to get just one
+ * PT_LOAD segment, and set the flags explicitly to make segments read-only.
+ */
+PHDRS
+{
+ text PT_LOAD FLAGS(5) FILEHDR PHDRS; /* PF_R|PF_X */
+ dynamic PT_DYNAMIC FLAGS(4); /* PF_R */
+ note PT_NOTE FLAGS(4); /* PF_R */
+ eh_frame_hdr PT_GNU_EH_FRAME;
+}
new file mode 100644
@@ -0,0 +1,12 @@
+/*
+ * This supplies .note.* sections to go into the PT_NOTE inside the vDSO text.
+ * Here we can supply some information useful to userland.
+ */
+
+#include <linux/uts.h>
+#include <linux/version.h>
+#include <linux/elfnote.h>
+
+ELFNOTE_START(Linux, 0, "a")
+ .long LINUX_VERSION_CODE
+ELFNOTE_END
new file mode 100644
@@ -0,0 +1,25 @@
+/*
+ * Linker script for 64-bit vDSO.
+ * We #include the file to define the layout details.
+ *
+ * This file defines the version script giving the user-exported symbols in
+ * the DSO.
+ */
+
+#define BUILD_VDSO64
+
+#include "vdso-layout.lds.S"
+
+/*
+ * This controls what userland symbols we export from the vDSO.
+ */
+VERSION {
+ LINUX_2.6 {
+ global:
+ clock_gettime;
+ __vdso_clock_gettime;
+ gettimeofday;
+ __vdso_gettimeofday;
+ local: *;
+ };
+}
new file mode 100644
@@ -0,0 +1,234 @@
+/*
+ * vdso2c - A vdso image preparation tool
+ * Copyright (c) 2014 Andy Lutomirski and others
+ * Licensed under the GPL v2
+ *
+ * vdso2c requires stripped and unstripped input. It would be trivial
+ * to fully strip the input in here, but, for reasons described below,
+ * we need to write a section table. Doing this is more or less
+ * equivalent to dropping all non-allocatable sections, but it's
+ * easier to let objcopy handle that instead of doing it ourselves.
+ * If we ever need to do something fancier than what objcopy provides,
+ * it would be straightforward to add here.
+ *
+ * We keep a section table for a few reasons:
+ *
+ * Binutils has issues debugging the vDSO: it reads the section table to
+ * find SHT_NOTE; it won't look at PT_NOTE for the in-memory vDSO, which
+ * would break build-id if we removed the section table. Binutils
+ * also requires that shstrndx != 0. See:
+ * https://sourceware.org/bugzilla/show_bug.cgi?id=17064
+ *
+ * elfutils might not look for PT_NOTE if there is a section table at
+ * all. I don't know whether this matters for any practical purpose.
+ *
+ * For simplicity, rather than hacking up a partial section table, we
+ * just write a mostly complete one. We omit non-dynamic symbols,
+ * though, since they're rather large.
+ *
+ * Once binutils gets fixed, we might be able to drop this for all but
+ * the 64-bit vdso, since build-id only works in kernel RPMs, and
+ * systems that update to new enough kernel RPMs will likely update
+ * binutils in sync. build-id has never worked for home-built kernel
+ * RPMs without manual symlinking, and I suspect that no one ever does
+ * that.
+ */
+
+/*
+ * Copyright (c) 2017 Oracle and/or its affiliates. All rights reserved.
+ */
+
+#include <inttypes.h>
+#include <stdint.h>
+#include <unistd.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <fcntl.h>
+#include <err.h>
+
+#include <sys/mman.h>
+#include <sys/types.h>
+#include <tools/be_byteshift.h>
+
+#include <linux/elf.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+
+const char *outfilename;
+
+/* Symbols that we need in vdso2c. */
+enum {
+ sym_vvar_start,
+ sym_VDSO_FAKE_SECTION_TABLE_START,
+ sym_VDSO_FAKE_SECTION_TABLE_END,
+ sym_vread_tick,
+ sym_vread_tick_patch_start,
+ sym_vread_tick_patch_end
+};
+
+struct vdso_sym {
+ const char *name;
+ int export;
+};
+
+struct vdso_sym required_syms[] = {
+ [sym_vvar_start] = {"vvar_start", 1},
+ [sym_VDSO_FAKE_SECTION_TABLE_START] = {
+ "VDSO_FAKE_SECTION_TABLE_START", 0
+ },
+ [sym_VDSO_FAKE_SECTION_TABLE_END] = {
+ "VDSO_FAKE_SECTION_TABLE_END", 0
+ },
+ [sym_vread_tick] = {"vread_tick", 1},
+ [sym_vread_tick_patch_start] = {"vread_tick_patch_start", 1},
+ [sym_vread_tick_patch_end] = {"vread_tick_patch_end", 1}
+};
+
+__attribute__((format(printf, 1, 2))) __attribute__((noreturn))
+static void fail(const char *format, ...)
+{
+ va_list ap;
+
+ va_start(ap, format);
+ fprintf(stderr, "Error: ");
+ vfprintf(stderr, format, ap);
+ if (outfilename)
+ unlink(outfilename);
+ exit(1);
+ va_end(ap);
+}
+
+/*
+ * Evil macros for big-endian reads and writes
+ */
+#define GBE(x, bits, ifnot) \
+ __builtin_choose_expr( \
+ (sizeof(*(x)) == bits/8), \
+ (__typeof__(*(x)))get_unaligned_be##bits(x), ifnot)
+
+#define LAST_GBE(x) \
+ __builtin_choose_expr(sizeof(*(x)) == 1, *(x), (void)(0))
+
+#define GET_BE(x) \
+ GBE(x, 64, GBE(x, 32, GBE(x, 16, LAST_GBE(x))))
+
+#define PBE(x, val, bits, ifnot) \
+ __builtin_choose_expr( \
+ (sizeof(*(x)) == bits/8), \
+ put_unaligned_be##bits((val), (x)), ifnot)
+
+#define LAST_PBE(x, val) \
+ __builtin_choose_expr(sizeof(*(x)) == 1, *(x) = (val), (void)(0))
+
+#define PUT_BE(x, val) \
+ PBE(x, val, 64, PBE(x, val, 32, PBE(x, val, 16, LAST_PBE(x, val))))
+
+#define NSYMS ARRAY_SIZE(required_syms)
+
+#define BITSFUNC3(name, bits, suffix) name##bits##suffix
+#define BITSFUNC2(name, bits, suffix) BITSFUNC3(name, bits, suffix)
+#define BITSFUNC(name) BITSFUNC2(name, ELF_BITS, )
+
+#define INT_BITS BITSFUNC2(int, ELF_BITS, _t)
+
+#define ELF_BITS_XFORM2(bits, x) Elf##bits##_##x
+#define ELF_BITS_XFORM(bits, x) ELF_BITS_XFORM2(bits, x)
+#define ELF(x) ELF_BITS_XFORM(ELF_BITS, x)
+
+#define ELF_BITS 64
+#include "vdso2c.h"
+#undef ELF_BITS
+
+#define ELF_BITS 32
+#include "vdso2c.h"
+#undef ELF_BITS
+
+static void go(void *raw_addr, size_t raw_len,
+ void *stripped_addr, size_t stripped_len,
+ FILE *outfile, const char *name)
+{
+ Elf64_Ehdr *hdr = (Elf64_Ehdr *)raw_addr;
+
+ if (hdr->e_ident[EI_CLASS] == ELFCLASS64) {
+ go64(raw_addr, raw_len, stripped_addr, stripped_len,
+ outfile, name);
+ } else if (hdr->e_ident[EI_CLASS] == ELFCLASS32) {
+ go32(raw_addr, raw_len, stripped_addr, stripped_len,
+ outfile, name);
+ } else {
+ fail("unknown ELF class\n");
+ }
+}
+
+static void map_input(const char *name, void **addr, size_t *len, int prot)
+{
+ off_t tmp_len;
+
+ int fd = open(name, O_RDONLY);
+
+ if (fd == -1)
+ err(1, "%s", name);
+
+ tmp_len = lseek(fd, 0, SEEK_END);
+ if (tmp_len == (off_t)-1)
+ err(1, "lseek");
+ *len = (size_t)tmp_len;
+
+ *addr = mmap(NULL, tmp_len, prot, MAP_PRIVATE, fd, 0);
+ if (*addr == MAP_FAILED)
+ err(1, "mmap");
+
+ close(fd);
+}
+
+int main(int argc, char **argv)
+{
+ size_t raw_len, stripped_len;
+ void *raw_addr, *stripped_addr;
+ FILE *outfile;
+ char *name, *tmp;
+ int namelen;
+
+ if (argc != 4) {
+ printf("Usage: vdso2c RAW_INPUT STRIPPED_INPUT OUTPUT\n");
+ return 1;
+ }
+
+ /*
+ * Figure out the struct name. If we're writing to a .so file,
+ * generate raw output insted.
+ */
+ name = strdup(argv[3]);
+ namelen = strlen(name);
+ if (namelen >= 3 && !strcmp(name + namelen - 3, ".so")) {
+ name = NULL;
+ } else {
+ tmp = strrchr(name, '/');
+ if (tmp)
+ name = tmp + 1;
+ tmp = strchr(name, '.');
+ if (tmp)
+ *tmp = '\0';
+ for (tmp = name; *tmp; tmp++)
+ if (*tmp == '-')
+ *tmp = '_';
+ }
+
+ map_input(argv[1], &raw_addr, &raw_len, PROT_READ);
+ map_input(argv[2], &stripped_addr, &stripped_len, PROT_READ);
+
+ outfilename = argv[3];
+ outfile = fopen(outfilename, "w");
+ if (!outfile)
+ err(1, "%s", argv[2]);
+
+ go(raw_addr, raw_len, stripped_addr, stripped_len, outfile, name);
+
+ munmap(raw_addr, raw_len);
+ munmap(stripped_addr, stripped_len);
+ fclose(outfile);
+
+ return 0;
+}
new file mode 100644
@@ -0,0 +1,143 @@
+/*
+ * Copyright (c) 2017 Oracle and/or its affiliates. All rights reserved.
+ */
+
+/*
+ * This file is included up to twice from vdso2c.c. It generates code for
+ * 32-bit and 64-bit vDSOs. We will eventually need both for 64-bit builds,
+ * since 32-bit vDSOs will then be built for 32-bit userspace.
+ */
+
+static void BITSFUNC(go)(void *raw_addr, size_t raw_len,
+ void *stripped_addr, size_t stripped_len,
+ FILE *outfile, const char *name)
+{
+ int found_load = 0;
+ unsigned long load_size = -1; /* Work around bogus warning */
+ unsigned long mapping_size;
+ int i;
+ unsigned long j;
+
+ ELF(Shdr) *symtab_hdr = NULL, *strtab_hdr;
+ ELF(Ehdr) *hdr = (ELF(Ehdr) *)raw_addr;
+ ELF(Dyn) *dyn = 0, *dyn_end = 0;
+ INT_BITS syms[NSYMS] = {};
+
+ ELF(Phdr) *pt = (ELF(Phdr) *)(raw_addr + GET_BE(&hdr->e_phoff));
+
+ /* Walk the segment table. */
+ for (i = 0; i < GET_BE(&hdr->e_phnum); i++) {
+ if (GET_BE(&pt[i].p_type) == PT_LOAD) {
+ if (found_load)
+ fail("multiple PT_LOAD segs\n");
+
+ if (GET_BE(&pt[i].p_offset) != 0 ||
+ GET_BE(&pt[i].p_vaddr) != 0)
+ fail("PT_LOAD in wrong place\n");
+
+ if (GET_BE(&pt[i].p_memsz) != GET_BE(&pt[i].p_filesz))
+ fail("cannot handle memsz != filesz\n");
+
+ load_size = GET_BE(&pt[i].p_memsz);
+ found_load = 1;
+ } else if (GET_BE(&pt[i].p_type) == PT_DYNAMIC) {
+ dyn = raw_addr + GET_BE(&pt[i].p_offset);
+ dyn_end = raw_addr + GET_BE(&pt[i].p_offset) +
+ GET_BE(&pt[i].p_memsz);
+ }
+ }
+ if (!found_load)
+ fail("no PT_LOAD seg\n");
+
+ if (stripped_len < load_size)
+ fail("stripped input is too short\n");
+
+ /* Walk the dynamic table */
+ for (i = 0; dyn + i < dyn_end &&
+ GET_BE(&dyn[i].d_tag) != DT_NULL; i++) {
+ typeof(dyn[i].d_tag) tag = GET_BE(&dyn[i].d_tag);
+ typeof(dyn[i].d_un.d_val) val = GET_BE(&dyn[i].d_un.d_val);
+
+ if ((tag == DT_RELSZ || tag == DT_RELASZ) && (val != 0))
+ fail("vdso image contains dynamic relocations\n");
+ }
+
+ /* Walk the section table */
+ for (i = 0; i < GET_BE(&hdr->e_shnum); i++) {
+ ELF(Shdr) *sh = raw_addr + GET_BE(&hdr->e_shoff) +
+ GET_BE(&hdr->e_shentsize) * i;
+ if (GET_BE(&sh->sh_type) == SHT_SYMTAB)
+ symtab_hdr = sh;
+ }
+
+ if (!symtab_hdr)
+ fail("no symbol table\n");
+
+ strtab_hdr = raw_addr + GET_BE(&hdr->e_shoff) +
+ GET_BE(&hdr->e_shentsize) * GET_BE(&symtab_hdr->sh_link);
+
+ /* Walk the symbol table */
+ for (i = 0;
+ i < GET_BE(&symtab_hdr->sh_size) / GET_BE(&symtab_hdr->sh_entsize);
+ i++) {
+ int k;
+
+ ELF(Sym) *sym = raw_addr + GET_BE(&symtab_hdr->sh_offset) +
+ GET_BE(&symtab_hdr->sh_entsize) * i;
+ const char *name = raw_addr + GET_BE(&strtab_hdr->sh_offset) +
+ GET_BE(&sym->st_name);
+
+ for (k = 0; k < NSYMS; k++) {
+ if (!strcmp(name, required_syms[k].name)) {
+ if (syms[k]) {
+ fail("duplicate symbol %s\n",
+ required_syms[k].name);
+ }
+
+ /*
+ * Careful: we use negative addresses, but
+ * st_value is unsigned, so we rely
+ * on syms[k] being a signed type of the
+ * correct width.
+ */
+ syms[k] = GET_BE(&sym->st_value);
+ }
+ }
+ }
+
+ /* Validate mapping addresses. */
+ if (syms[sym_vvar_start] % 8192)
+ fail("vvar_begin must be a multiple of 8192\n");
+
+ if (!name) {
+ fwrite(stripped_addr, stripped_len, 1, outfile);
+ return;
+ }
+
+ mapping_size = (stripped_len + 8191) / 8192 * 8192;
+
+ fprintf(outfile, "/* AUTOMATICALLY GENERATED -- DO NOT EDIT */\n\n");
+ fprintf(outfile, "#include <linux/cache.h>\n");
+ fprintf(outfile, "#include <asm/vdso.h>\n");
+ fprintf(outfile, "\n");
+ fprintf(outfile,
+ "static unsigned char raw_data[%lu] __ro_after_init __aligned(8192)= {",
+ mapping_size);
+ for (j = 0; j < stripped_len; j++) {
+ if (j % 10 == 0)
+ fprintf(outfile, "\n\t");
+ fprintf(outfile, "0x%02X, ",
+ (int)((unsigned char *)stripped_addr)[j]);
+ }
+ fprintf(outfile, "\n};\n\n");
+
+ fprintf(outfile, "const struct vdso_image %s_builtin = {\n", name);
+ fprintf(outfile, "\t.data = raw_data,\n");
+ fprintf(outfile, "\t.size = %lu,\n", mapping_size);
+ for (i = 0; i < NSYMS; i++) {
+ if (required_syms[i].export && syms[i])
+ fprintf(outfile, "\t.sym_%s = %" PRIi64 ",\n",
+ required_syms[i].name, (int64_t)syms[i]);
+ }
+ fprintf(outfile, "};\n");
+}
new file mode 100644
@@ -0,0 +1 @@
+vdso32.lds
new file mode 100644
@@ -0,0 +1,26 @@
+/*
+ * Copyright (c) 2017 Oracle and/or its affiliates. All rights reserved.
+ */
+
+#define BUILD_VDSO32
+
+#ifndef CONFIG_CC_OPTIMIZE_FOR_SIZE
+#undef CONFIG_OPTIMIZE_INLINING
+#endif
+
+#ifdef CONFIG_SPARC64
+
+/*
+ * in case of a 32 bit VDSO for a 64 bit kernel fake a 32 bit kernel
+ * configuration
+ */
+#undef CONFIG_64BIT
+#undef CONFIG_SPARC64
+#define BUILD_VDSO32_64
+#define CONFIG_32BIT
+#undef CONFIG_QUEUED_RWLOCKS
+#undef CONFIG_QUEUED_SPINLOCKS
+
+#endif
+
+#include "../vclock_gettime.c"
new file mode 100644
@@ -0,0 +1,12 @@
+/*
+ * This supplies .note.* sections to go into the PT_NOTE inside the vDSO
+ * text. Here we can supply some information useful to userland.
+ */
+
+#include <linux/uts.h>
+#include <linux/version.h>
+#include <linux/elfnote.h>
+
+ELFNOTE_START(Linux, 0, "a")
+ .long LINUX_VERSION_CODE
+ELFNOTE_END
new file mode 100644
@@ -0,0 +1,24 @@
+/*
+ * Linker script for sparc32 vDSO
+ * We #include the file to define the layout details.
+ *
+ * This file defines the version script giving the user-exported symbols in
+ * the DSO.
+ */
+
+#define BUILD_VDSO32
+#include "../vdso-layout.lds.S"
+
+/*
+ * This controls what userland symbols we export from the vDSO.
+ */
+VERSION {
+ LINUX_2.6 {
+ global:
+ clock_gettime;
+ __vdso_clock_gettime;
+ gettimeofday;
+ __vdso_gettimeofday;
+ local: *;
+ };
+}
new file mode 100644
@@ -0,0 +1,268 @@
+/*
+ * Set up the VMAs to tell the VM about the vDSO.
+ * Copyright 2007 Andi Kleen, SUSE Labs.
+ * Subject to the GPL, v.2
+ */
+
+/*
+ * Copyright (c) 2017 Oracle and/or its affiliates. All rights reserved.
+ */
+
+#include <linux/mm.h>
+#include <linux/err.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/init.h>
+#include <linux/linkage.h>
+#include <linux/random.h>
+#include <linux/elf.h>
+#include <asm/vdso.h>
+#include <asm/vvar.h>
+#include <asm/page.h>
+
+unsigned int __read_mostly vdso_enabled = 1;
+
+static struct vm_special_mapping vvar_mapping = {
+ .name = "[vvar]"
+};
+
+#ifdef CONFIG_SPARC64
+static struct vm_special_mapping vdso_mapping64 = {
+ .name = "[vdso]"
+};
+#endif
+
+#ifdef CONFIG_COMPAT
+static struct vm_special_mapping vdso_mapping32 = {
+ .name = "[vdso]"
+};
+#endif
+
+struct vvar_data *vvar_data;
+
+#define SAVE_INSTR_SIZE 4
+
+/*
+ * Allocate pages for the vdso and vvar, and copy in the vdso text from the
+ * kernel image.
+ */
+int __init init_vdso_image(const struct vdso_image *image,
+ struct vm_special_mapping *vdso_mapping)
+{
+ int i;
+ struct page *dp, **dpp = NULL;
+ int dnpages = 0;
+ struct page *cp, **cpp = NULL;
+ int cnpages = (image->size) / PAGE_SIZE;
+
+ /*
+ * First, the vdso text. This is initialied data, an integral number of
+ * pages long.
+ */
+ if (WARN_ON(image->size % PAGE_SIZE != 0))
+ goto oom;
+
+ cpp = kcalloc(cnpages, sizeof(struct page *), GFP_KERNEL);
+ vdso_mapping->pages = cpp;
+
+ if (!cpp)
+ goto oom;
+
+ if (vdso_fix_stick) {
+ /*
+ * If the system uses %tick instead of %stick, patch the VDSO
+ * with instruction reading %tick instead of %stick.
+ */
+ unsigned int j, k = SAVE_INSTR_SIZE;
+ unsigned char *data = image->data;
+
+ for (j = image->sym_vread_tick_patch_start;
+ j < image->sym_vread_tick_patch_end; j++) {
+
+ data[image->sym_vread_tick + k] = data[j];
+ k++;
+ }
+ }
+
+ for (i = 0; i < cnpages; i++) {
+ cp = alloc_page(GFP_KERNEL);
+ if (!cp)
+ goto oom;
+ cpp[i] = cp;
+ copy_page(page_address(cp), image->data + i * PAGE_SIZE);
+ }
+
+ /*
+ * Now the vvar page. This is uninitialized data.
+ */
+
+ if (vvar_data == NULL) {
+ dnpages = (sizeof(struct vvar_data) / PAGE_SIZE) + 1;
+ if (WARN_ON(dnpages != 1))
+ goto oom;
+ dpp = kcalloc(dnpages, sizeof(struct page *), GFP_KERNEL);
+ vvar_mapping.pages = dpp;
+
+ if (!dpp)
+ goto oom;
+
+ dp = alloc_page(GFP_KERNEL);
+ if (!dp)
+ goto oom;
+
+ dpp[0] = dp;
+ vvar_data = page_address(dp);
+ memset(vvar_data, 0, PAGE_SIZE);
+
+ vvar_data->seq = 0;
+ }
+
+ return 0;
+ oom:
+ if (cpp != NULL) {
+ for (i = 0; i < cnpages; i++) {
+ if (cpp[i] != NULL)
+ __free_page(cpp[i]);
+ }
+ kfree(cpp);
+ vdso_mapping->pages = NULL;
+ }
+
+ if (dpp != NULL) {
+ for (i = 0; i < dnpages; i++) {
+ if (dpp[i] != NULL)
+ __free_page(dpp[i]);
+ }
+ kfree(dpp);
+ vvar_mapping.pages = NULL;
+ }
+
+ pr_warn("Cannot allocate vdso\n");
+ vdso_enabled = 0;
+ return -ENOMEM;
+}
+
+static int __init init_vdso(void)
+{
+ int err = 0;
+#ifdef CONFIG_SPARC64
+ err = init_vdso_image(&vdso_image_64_builtin, &vdso_mapping64);
+ if (err)
+ return err;
+#endif
+
+#ifdef CONFIG_COMPAT
+ err = init_vdso_image(&vdso_image_32_builtin, &vdso_mapping32);
+#endif
+ return err;
+
+}
+subsys_initcall(init_vdso);
+
+struct linux_binprm;
+
+/* Shuffle the vdso up a bit, randomly. */
+static unsigned long vdso_addr(unsigned long start, unsigned int len)
+{
+ unsigned int offset;
+
+ /* This loses some more bits than a modulo, but is cheaper */
+ offset = get_random_int() & (PTRS_PER_PTE - 1);
+ return start + (offset << PAGE_SHIFT);
+}
+
+static int map_vdso(const struct vdso_image *image,
+ struct vm_special_mapping *vdso_mapping)
+{
+ struct mm_struct *mm = current->mm;
+ struct vm_area_struct *vma;
+ unsigned long text_start, addr = 0;
+ int ret = 0;
+
+ down_write(&mm->mmap_sem);
+
+ /*
+ * First, get an unmapped region: then randomize it, and make sure that
+ * region is free.
+ */
+ if (current->flags & PF_RANDOMIZE) {
+ addr = get_unmapped_area(NULL, 0,
+ image->size - image->sym_vvar_start,
+ 0, 0);
+ if (IS_ERR_VALUE(addr)) {
+ ret = addr;
+ goto up_fail;
+ }
+ addr = vdso_addr(addr, image->size - image->sym_vvar_start);
+ }
+ addr = get_unmapped_area(NULL, addr,
+ image->size - image->sym_vvar_start, 0, 0);
+ if (IS_ERR_VALUE(addr)) {
+ ret = addr;
+ goto up_fail;
+ }
+
+ text_start = addr - image->sym_vvar_start;
+ current->mm->context.vdso = (void __user *)text_start;
+
+ /*
+ * MAYWRITE to allow gdb to COW and set breakpoints
+ */
+ vma = _install_special_mapping(mm,
+ text_start,
+ image->size,
+ VM_READ|VM_EXEC|
+ VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
+ vdso_mapping);
+
+ if (IS_ERR(vma)) {
+ ret = PTR_ERR(vma);
+ goto up_fail;
+ }
+
+ vma = _install_special_mapping(mm,
+ addr,
+ -image->sym_vvar_start,
+ VM_READ|VM_MAYREAD,
+ &vvar_mapping);
+
+ if (IS_ERR(vma)) {
+ ret = PTR_ERR(vma);
+ do_munmap(mm, text_start, image->size, NULL);
+ }
+
+up_fail:
+ if (ret)
+ current->mm->context.vdso = NULL;
+
+ up_write(&mm->mmap_sem);
+ return ret;
+}
+
+int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
+{
+
+ if (!vdso_enabled)
+ return 0;
+
+#if defined CONFIG_COMPAT
+ if (!(is_32bit_task()))
+ return map_vdso(&vdso_image_64_builtin, &vdso_mapping64);
+ else
+ return map_vdso(&vdso_image_32_builtin, &vdso_mapping32);
+#else
+ return map_vdso(&vdso_image_64_builtin, &vdso_mapping64);
+#endif
+
+}
+
+static __init int vdso_setup(char *s)
+{
+ int err;
+ unsigned long val;
+
+ err = kstrtoul(s, 10, &val);
+ vdso_enabled = val;
+ return err;
+}
+__setup("vdso=", vdso_setup);