ARM: vdso: Set BUILD_VDSO32 and provide 32bit fallbacks

Setting BUILD_VDSO32 is required to expose the legacy 32bit interfaces in the generic VDSO code which are going to be hidden behind an #ifdef BUILD_VDSO32. The 32bit fallbacks are necessary to remove the existing VDSO_HAS_32BIT_FALLBACK hackery. Signed-off-by: Thomas Gleixner <[email protected]> Tested-by: Vincenzo Frascino <[email protected]> Cc: [email protected] Link: https://lore.kernel.org/r/[email protected]
niw · Jan 14, 2020 · 715f23b · 715f23b
1 parent 3b5584a
commit 715f23b
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Showing 2 changed files with 37 additions and 1 deletion.
diff --git a/arch/arm/include/asm/vdso/gettimeofday.h b/arch/arm/include/asm/vdso/gettimeofday.h
@@ -52,6 +52,24 @@ static __always_inline long clock_gettime_fallback(
 	return ret;
 }
 
+static __always_inline long clock_gettime32_fallback(
+					clockid_t _clkid,
+					struct old_timespec32 *_ts)
+{
+	register struct old_timespec32 *ts asm("r1") = _ts;
+	register clockid_t clkid asm("r0") = _clkid;
+	register long ret asm ("r0");
+	register long nr asm("r7") = __NR_clock_gettime;
+
+	asm volatile(
+	"	swi #0\n"
+	: "=r" (ret)
+	: "r" (clkid), "r" (ts), "r" (nr)
+	: "memory");
+
+	return ret;
+}
+
 static __always_inline int clock_getres_fallback(
 					clockid_t _clkid,
 					struct __kernel_timespec *_ts)
@@ -70,6 +88,24 @@ static __always_inline int clock_getres_fallback(
 	return ret;
 }
 
+static __always_inline int clock_getres32_fallback(
+					clockid_t _clkid,
+					struct old_timespec32 *_ts)
+{
+	register struct old_timespec32 *ts asm("r1") = _ts;
+	register clockid_t clkid asm("r0") = _clkid;
+	register long ret asm ("r0");
+	register long nr asm("r7") = __NR_clock_getres;
+
+	asm volatile(
+	"       swi #0\n"
+	: "=r" (ret)
+	: "r" (clkid), "r" (ts), "r" (nr)
+	: "memory");
+
+	return ret;
+}
+
 static __always_inline u64 __arch_get_hw_counter(int clock_mode)
 {
 #ifdef CONFIG_ARM_ARCH_TIMER

diff --git a/arch/arm/vdso/Makefile b/arch/arm/vdso/Makefile
@@ -14,7 +14,7 @@ targets := $(obj-vdso) vdso.so vdso.so.dbg vdso.so.raw vdso.lds
 obj-vdso := $(addprefix $(obj)/, $(obj-vdso))
 
 ccflags-y := -fPIC -fno-common -fno-builtin -fno-stack-protector
-ccflags-y += -DDISABLE_BRANCH_PROFILING
+ccflags-y += -DDISABLE_BRANCH_PROFILING -DBUILD_VDSO32
 
 ldflags-$(CONFIG_CPU_ENDIAN_BE8) := --be8
 ldflags-y := -Bsymbolic --no-undefined -soname=linux-vdso.so.1 \