From 3379ac59af3ab124ce619b10cd92ecd0fc254772 Mon Sep 17 00:00:00 2001
From: John Baldwin <jhb@FreeBSD.org>
Date: Wed, 23 Feb 2011 13:19:14 +0000
Subject: [PATCH] Expose the umtx_key structure and API to the rest of the
 kernel.

MFC after:	3 days
---
 sys/kern/kern_umtx.c | 52 ++------------------------------------------
 sys/sys/umtx.h       | 51 +++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 53 insertions(+), 50 deletions(-)

diff --git a/sys/kern/kern_umtx.c b/sys/kern/kern_umtx.c
index 2422a19ddd0..1edff748ffe 100644
--- a/sys/kern/kern_umtx.c
+++ b/sys/kern/kern_umtx.c
@@ -59,41 +59,9 @@ __FBSDID("$FreeBSD$");
 #include <compat/freebsd32/freebsd32_proto.h>
 #endif
 
-enum {
-	TYPE_SIMPLE_WAIT,
-	TYPE_CV,
-	TYPE_SEM,
-	TYPE_SIMPLE_LOCK,
-	TYPE_NORMAL_UMUTEX,
-	TYPE_PI_UMUTEX,
-	TYPE_PP_UMUTEX,
-	TYPE_RWLOCK
-};
-
 #define _UMUTEX_TRY		1
 #define _UMUTEX_WAIT		2
 
-/* Key to represent a unique userland synchronous object */
-struct umtx_key {
-	int	hash;
-	int	type;
-	int	shared;
-	union {
-		struct {
-			vm_object_t	object;
-			uintptr_t	offset;
-		} shared;
-		struct {
-			struct vmspace	*vs;
-			uintptr_t	addr;
-		} private;
-		struct {
-			void		*a;
-			uintptr_t	b;
-		} both;
-	} info;
-};
-
 /* Priority inheritance mutex info. */
 struct umtx_pi {
 	/* Owner thread */
@@ -208,10 +176,6 @@ struct umtxq_chain {
 #define	UMTX_CHAINS		512
 #define	UMTX_SHIFTS		(__WORD_BIT - 9)
 
-#define THREAD_SHARE		0
-#define PROCESS_SHARE		1
-#define AUTO_SHARE		2
-
 #define	GET_SHARE(flags)	\
     (((flags) & USYNC_PROCESS_SHARED) == 0 ? THREAD_SHARE : PROCESS_SHARE)
 
@@ -237,10 +201,6 @@ static void umtxq_insert_queue(struct umtx_q *uq, int q);
 static void umtxq_remove_queue(struct umtx_q *uq, int q);
 static int umtxq_sleep(struct umtx_q *uq, const char *wmesg, int timo);
 static int umtxq_count(struct umtx_key *key);
-static int umtx_key_match(const struct umtx_key *k1, const struct umtx_key *k2);
-static int umtx_key_get(void *addr, int type, int share,
-	struct umtx_key *key);
-static void umtx_key_release(struct umtx_key *key);
 static struct umtx_pi *umtx_pi_alloc(int);
 static void umtx_pi_free(struct umtx_pi *pi);
 static int do_unlock_pp(struct thread *td, struct umutex *m, uint32_t flags);
@@ -307,14 +267,6 @@ umtxq_hash(struct umtx_key *key)
 	key->hash = ((n * GOLDEN_RATIO_PRIME) >> UMTX_SHIFTS) % UMTX_CHAINS;
 }
 
-static inline int
-umtx_key_match(const struct umtx_key *k1, const struct umtx_key *k2)
-{
-	return (k1->type == k2->type &&
-		k1->info.both.a == k2->info.both.a &&
-	        k1->info.both.b == k2->info.both.b);
-}
-
 static inline struct umtxq_chain *
 umtxq_getchain(struct umtx_key *key)
 {
@@ -567,7 +519,7 @@ umtxq_sleep(struct umtx_q *uq, const char *wmesg, int timo)
 /*
  * Convert userspace address into unique logical address.
  */
-static int
+int
 umtx_key_get(void *addr, int type, int share, struct umtx_key *key)
 {
 	struct thread *td = curthread;
@@ -613,7 +565,7 @@ umtx_key_get(void *addr, int type, int share, struct umtx_key *key)
 /*
  * Release key.
  */
-static inline void
+void
 umtx_key_release(struct umtx_key *key)
 {
 	if (key->shared)
diff --git a/sys/sys/umtx.h b/sys/sys/umtx.h
index c7d69450dea..306c01c1a00 100644
--- a/sys/sys/umtx.h
+++ b/sys/sys/umtx.h
@@ -171,8 +171,59 @@ umtx_wake(u_long *p, int nr_wakeup)
 
 #else
 
+/*
+ * The umtx_key structure is used by both the Linux futex code and the
+ * umtx implementation to map userland addresses to unique keys.
+ */
+
+enum {
+	TYPE_SIMPLE_WAIT,
+	TYPE_CV,
+	TYPE_SEM,
+	TYPE_SIMPLE_LOCK,
+	TYPE_NORMAL_UMUTEX,
+	TYPE_PI_UMUTEX,
+	TYPE_PP_UMUTEX,
+	TYPE_RWLOCK,
+};
+
+/* Key to represent a unique userland synchronous object */
+struct umtx_key {
+	int	hash;
+	int	type;
+	int	shared;
+	union {
+		struct {
+			struct vm_object *object;
+			uintptr_t	offset;
+		} shared;
+		struct {
+			struct vmspace	*vs;
+			uintptr_t	addr;
+		} private;
+		struct {
+			void		*a;
+			uintptr_t	b;
+		} both;
+	} info;
+};
+
+#define THREAD_SHARE		0
+#define PROCESS_SHARE		1
+#define AUTO_SHARE		2
+
 struct thread;
 
+static inline int
+umtx_key_match(const struct umtx_key *k1, const struct umtx_key *k2)
+{
+	return (k1->type == k2->type &&
+		k1->info.both.a == k2->info.both.a &&
+	        k1->info.both.b == k2->info.both.b);
+}
+
+int umtx_key_get(void *, int, int, struct umtx_key *);
+void umtx_key_release(struct umtx_key *);
 struct umtx_q *umtxq_alloc(void);
 void umtxq_free(struct umtx_q *);
 int kern_umtx_wake(struct thread *, void *, int, int);
-- 
2.45.2