6 files changed, 62 insertions, 12 deletions
diff --git a/include/vdso/clocksource.h b/include/vdso/clocksource.h
index c682e7c60273..bce81c02a7c6 100644
--- a/include/vdso/clocksource.h
+++ b/include/vdso/clocksource.h
@@ -4,13 +4,11 @@
 
 #include <vdso/limits.h>
 
-#ifdef CONFIG_GENERIC_GETTIMEOFDAY
 #include <asm/vdso/clocksource.h>
-#endif /* CONFIG_GENERIC_GETTIMEOFDAY */
 
 enum vdso_clock_mode {
 	VDSO_CLOCKMODE_NONE,
-#ifdef CONFIG_GENERIC_GETTIMEOFDAY
+#ifdef VDSO_ARCH_CLOCKMODES
 	VDSO_ARCH_CLOCKMODES,
 #endif
 	VDSO_CLOCKMODE_MAX,
diff --git a/include/vdso/datapage.h b/include/vdso/datapage.h
index 5977723fb3b5..09897f76ae07 100644
--- a/include/vdso/datapage.h
+++ b/include/vdso/datapage.h
@@ -2,7 +2,7 @@
 #ifndef __VDSO_DATAPAGE_H
 #define __VDSO_DATAPAGE_H
 
-#ifndef __ASSEMBLY__
+#ifndef __ASSEMBLER__
 
 #include <linux/types.h>
 
@@ -176,7 +176,7 @@ enum vdso_pages {
 	VDSO_NR_PAGES
 };
 
-#else /* !__ASSEMBLY__ */
+#else /* !__ASSEMBLER__ */
 
 #ifdef CONFIG_VDSO_GETRANDOM
 #define __vdso_u_rng_data	PROVIDE(vdso_u_rng_data = vdso_u_data + 2 * PAGE_SIZE);
@@ -197,6 +197,6 @@ enum vdso_pages {
 	__vdso_u_arch_data					\
 
 
-#endif /* !__ASSEMBLY__ */
+#endif /* !__ASSEMBLER__ */
 
 #endif /* __VDSO_DATAPAGE_H */
diff --git a/include/vdso/futex.h b/include/vdso/futex.h
new file mode 100644
index 000000000000..3cd175eefe64
--- /dev/null
+++ b/include/vdso/futex.h
@@ -0,0 +1,52 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _VDSO_FUTEX_H
+#define _VDSO_FUTEX_H
+
+#include <uapi/linux/types.h>
+
+/**
+ * __vdso_futex_robust_list64_try_unlock - Try to unlock an uncontended robust futex
+ *					   with a 64-bit pending op pointer
+ * @lock:	Pointer to the futex lock object
+ * @tid:	The TID of the calling task
+ * @pop:	Pointer to the task's robust_list_head::list_pending_op
+ *
+ * Return: The content of *@lock. On success this is the same as @tid.
+ *
+ * The function implements:
+ *	if (atomic_try_cmpxchg(lock, &tid, 0))
+ *		*op = NULL;
+ *	return tid;
+ *
+ * There is a race between a successful unlock and clearing the pending op
+ * pointer in the robust list head. If the calling task is interrupted in the
+ * race window and has to handle a (fatal) signal on return to user space then
+ * the kernel handles the clearing of @pending_op before attempting to deliver
+ * the signal. That ensures that a task cannot exit with a potentially invalid
+ * pending op pointer.
+ *
+ * User space uses it in the following way:
+ *
+ * if (__vdso_futex_robust_list64_try_unlock(lock, tid, &pending_op) != tid)
+ *	err = sys_futex($OP | FUTEX_ROBUST_UNLOCK,....);
+ *
+ * If the unlock attempt fails due to the FUTEX_WAITERS bit set in the lock,
+ * then the syscall does the unlock, clears the pending op pointer and wakes the
+ * requested number of waiters.
+ */
+__u32 __vdso_futex_robust_list64_try_unlock(__u32 *lock, __u32 tid, __u64 *pop);
+
+/**
+ * __vdso_futex_robust_list32_try_unlock - Try to unlock an uncontended robust futex
+ *					   with a 32-bit pending op pointer
+ * @lock:	Pointer to the futex lock object
+ * @tid:	The TID of the calling task
+ * @pop:	Pointer to the task's robust_list_head::list_pending_op
+ *
+ * Return: The content of *@lock. On success this is the same as @tid.
+ *
+ * Same as __vdso_futex_robust_list64_try_unlock() just with a 32-bit @pop pointer.
+ */
+__u32 __vdso_futex_robust_list32_try_unlock(__u32 *lock, __u32 tid, __u32 *pop);
+
+#endif
diff --git a/include/vdso/helpers.h b/include/vdso/helpers.h
index a3bf4f1c0d37..65151b681c4f 100644
--- a/include/vdso/helpers.h
+++ b/include/vdso/helpers.h
@@ -2,7 +2,7 @@
 #ifndef __VDSO_HELPERS_H
 #define __VDSO_HELPERS_H
 
-#ifndef __ASSEMBLY__
+#ifndef __ASSEMBLER__
 
 #include <asm/barrier.h>
 #include <vdso/datapage.h>
@@ -111,6 +111,6 @@ static __always_inline void vdso_write_end(struct vdso_time_data *vd)
 	vdso_write_seq_end(&vc[CS_RAW]);
 }
 
-#endif /* !__ASSEMBLY__ */
+#endif /* !__ASSEMBLER__ */
 
 #endif /* __VDSO_HELPERS_H */
diff --git a/include/vdso/processor.h b/include/vdso/processor.h
index fbe8265ea3c4..cc781912a696 100644
--- a/include/vdso/processor.h
+++ b/include/vdso/processor.h
@@ -5,10 +5,10 @@
 #ifndef __VDSO_PROCESSOR_H
 #define __VDSO_PROCESSOR_H
 
-#ifndef __ASSEMBLY__
+#ifndef __ASSEMBLER__
 
 #include <asm/vdso/processor.h>
 
-#endif /* __ASSEMBLY__ */
+#endif /* __ASSEMBLER__ */
 
 #endif /* __VDSO_PROCESSOR_H */
diff --git a/include/vdso/vsyscall.h b/include/vdso/vsyscall.h
index b0fdc9c6bf43..c5c2a2c07857 100644
--- a/include/vdso/vsyscall.h
+++ b/include/vdso/vsyscall.h
@@ -2,13 +2,13 @@
 #ifndef __VDSO_VSYSCALL_H
 #define __VDSO_VSYSCALL_H
 
-#ifndef __ASSEMBLY__
+#ifndef __ASSEMBLER__
 
 #include <asm/vdso/vsyscall.h>
 
 unsigned long vdso_update_begin(void);
 void vdso_update_end(unsigned long flags);
 
-#endif /* !__ASSEMBLY__ */
+#endif /* !__ASSEMBLER__ */
 
 #endif /* __VDSO_VSYSCALL_H */