sys: Avoid relying on pollution from refcount.h

Fix up headers which previously assumed that refcount.h includes
systm.h, and make them more self-contained.  Then, replace the systm.h
include in refcount with kassert.h.

Reviewed by:	imp, kib
MFC after:	1 week
Differential Revision:	https://reviews.freebsd.org/D47450

sys/powerpc/include/counter.h

@@ -100,6 +100,8 @@ counter_u64_add(counter_u64_t c, int64_t inc)
 
 #else	/* !64bit */
 
+#include <sys/systm.h>
+
 #define	counter_enter()	critical_enter()
 #define	counter_exit()	critical_exit()
 

sys/sys/_lock.h

@@ -33,8 +33,8 @@
 
 struct lock_object {
 	const	char *lo_name;		/* Individual lock name. */
-	u_int	lo_flags;
-	u_int	lo_data;		/* General class specific data. */
+	unsigned int lo_flags;
+	unsigned int lo_data;		/* General class specific data. */
 	struct	witness *lo_witness;	/* Data for witness. */
 };
 

sys/sys/_mutex.h

@@ -31,6 +31,8 @@
 #ifndef _SYS__MUTEX_H_
 #define	_SYS__MUTEX_H_
 
+#include <sys/_types.h>
+#include <sys/_lock.h>
 #include <machine/param.h>
 
 /*
@@ -44,7 +46,7 @@
  */
 struct mtx {
 	struct lock_object	lock_object;	/* Common lock properties. */
-	volatile uintptr_t	mtx_lock;	/* Owner and flags. */
+	volatile __uintptr_t	mtx_lock;	/* Owner and flags. */
 };
 
 /*
@@ -58,7 +60,7 @@ struct mtx {
  */
 struct mtx_padalign {
 	struct lock_object	lock_object;	/* Common lock properties. */
-	volatile uintptr_t	mtx_lock;	/* Owner and flags. */
+	volatile __uintptr_t	mtx_lock;	/* Owner and flags. */
 } __aligned(CACHE_LINE_SIZE);
 
 #endif /* !_SYS__MUTEX_H_ */

sys/sys/_rmlock.h

@@ -32,6 +32,14 @@
 #ifndef _SYS__RMLOCK_H_
 #define	_SYS__RMLOCK_H_
 
+#include <sys/_cpuset.h>
+#include <sys/_lock.h>
+#include <sys/_mutex.h>
+#include <sys/queue.h>
+#include <sys/_sx.h>
+
+struct thread;
+
 /*
  * Mostly reader/occasional writer lock.
  */
@@ -66,8 +74,6 @@ struct rm_priotracker {
 	LIST_ENTRY(rm_priotracker) rmp_qentry;
 };
 
-#include <sys/_mutex.h>
-
 struct rmslock_pcpu;
 
 struct rmslock {

sys/sys/_rwlock.h

@@ -28,6 +28,8 @@
 #ifndef _SYS__RWLOCK_H_
 #define	_SYS__RWLOCK_H_
 
+#include <sys/_types.h>
+#include <sys/_lock.h>
 #include <machine/param.h>
 
 /*
@@ -41,7 +43,7 @@
  */
 struct rwlock {
 	struct lock_object	lock_object;
-	volatile uintptr_t	rw_lock;
+	volatile __uintptr_t	rw_lock;
 };
 
 /*
@@ -55,7 +57,7 @@ struct rwlock {
  */
 struct rwlock_padalign {
 	struct lock_object	lock_object;
-	volatile uintptr_t	rw_lock;
+	volatile __uintptr_t	rw_lock;
 } __aligned(CACHE_LINE_SIZE);
 
 #endif /* !_SYS__RWLOCK_H_ */

sys/sys/_sx.h

@@ -31,12 +31,15 @@
 #ifndef	_SYS__SX_H_
 #define	_SYS__SX_H_
 
+#include <sys/_types.h>
+#include <sys/_lock.h>
+
 /*
  * Shared/exclusive lock main structure definition.
  */
 struct sx {
 	struct lock_object	lock_object;
-	volatile uintptr_t	sx_lock;
+	volatile __uintptr_t	sx_lock;
 };
 
 #endif	/* !_SYS__SX_H_ */

sys/sys/file.h

@@ -37,13 +37,16 @@
 #include <sys/fcntl.h>
 #include <sys/unistd.h>
 #else
-#include <sys/queue.h>
-#include <sys/refcount.h>
+#include <sys/errno.h>
 #include <sys/_lock.h>
 #include <sys/_mutex.h>
+#include <sys/_null.h>
+#include <sys/queue.h>
+#include <sys/refcount.h>
 #include <vm/vm.h>
 
 struct filedesc;
+struct proc;
 struct stat;
 struct thread;
 struct uio;

sys/sys/ktls.h

@@ -28,8 +28,11 @@
 #define	_SYS_KTLS_H_
 
 #ifdef _KERNEL
+#include <sys/_null.h>
 #include <sys/refcount.h>
 #include <sys/_task.h>
+
+#include <machine/param.h>
 #endif
 
 struct tls_record_layer {

sys/sys/refcount.h

@@ -28,13 +28,14 @@
 #ifndef __SYS_REFCOUNT_H__
 #define __SYS_REFCOUNT_H__
 
-#include <machine/atomic.h>
-
-#include <sys/systm.h>
+#include <sys/types.h>
+#include <sys/kassert.h>
 #if !defined(_KERNEL) && !defined(_STANDALONE)
 #include <stdbool.h>
 #endif
 
+#include <machine/atomic.h>
+
 #define	REFCOUNT_SATURATED(val)		(((val) & (1U << 31)) != 0)
 #define	REFCOUNT_SATURATION_VALUE	(3U << 30)
 

sys/sys/sglist.h

@@ -55,6 +55,7 @@ struct sglist {
 
 struct bio;
 struct mbuf;
+struct thread;
 struct uio;
 
 static __inline void

tools/build/test-includes/badfiles.inc

@@ -100,7 +100,6 @@ BADHDRS= \
 	sys/prng.h \
 	sys/qmath.h \
 	sys/racct.h \
-	sys/refcount.h \
 	sys/resourcevar.h \
 	sys/rman.h \
 	sys/rmlock.h \