Enable vmspace sharing on SMP. Major changes are,

- %fs register is added to trapframe and saved/restored upon kernel entry/exit.
- Per-cpu pages are no longer mapped at the same virtual address.
- Each cpu now has a separate gdt selector table. A new segment selector
  is added to point to per-cpu pages, per-cpu global variables are now
  accessed through this new selector (%fs). The selectors in gdt table are
  rearranged for cache line optimization.
- fask_vfork is now on as default for both UP and SMP.
- Some aio code cleanup.

Reviewed by:	Alan Cox	<alc@cs.rice.edu>
		John Dyson	<dyson@iquest.net>
		Julian Elischer	<julian@whistel.com>
		Bruce Evans	<bde@zeta.org.au>
		David Greenman	<dg@root.com>

1 files changed, 147 insertions, 0 deletions

diff --git a/sys/i386/include/globals.h b/sys/i386/include/globals.h
new file mode 100644
index 0000000..5a770f1
--- /dev/null
+++ b/sys/i386/include/globals.h
@@ -0,0 +1,147 @@
+/*-
+ * Copyright (c) 1999 Luoqi Chen <luoqi@freebsd.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $Id$
+ */
+
+#ifndef	_MACHINE_GLOBALS_H_
+#define	_MACHINE_GLOBALS_H_
+
+#ifdef KERNEL
+
+#define	GLOBAL_LVALUE(name, type) \
+	(*(type *)_global_ptr_##name())
+	
+#define	GLOBAL_RVALUE(name, type) \
+	((type)_global_##name())
+
+/* non-volatile version */
+#define	GLOBAL_LVALUE_NV(name, type) \
+	(*(type *)_global_ptr_##name##_nv())
+	
+#define	GLOBAL_RVALUE_NV(name, type) \
+	((type)_global_##name##_nv())
+
+#define	GLOBAL_FUNC(name) \
+	static __inline void *_global_ptr_##name(void) { \
+		void *val; \
+		__asm __volatile("movl $gd_" #name ",%0;" \
+			"addl %%fs:globaldata,%0" : "=r" (val)); \
+		return (val); \
+	} \
+	static __inline void *_global_ptr_##name##_nv(void) { \
+		void *val; \
+		__asm("movl $gd_" #name ",%0;" \
+			"addl %%fs:globaldata,%0" : "=r" (val)); \
+		return (val); \
+	} \
+	static __inline int _global_##name(void) { \
+		int val; \
+		__asm __volatile("movl %%fs:gd_" #name ",%0" : "=r" (val)); \
+		return (val); \
+	} \
+	static __inline int _global_##name##_nv(void) { \
+		int val; \
+		__asm("movl %%fs:gd_" #name ",%0" : "=r" (val)); \
+		return (val); \
+	} \
+	static __inline void _global_##name##_set(int val) { \
+		__asm __volatile("movl %0,%%fs:gd_" #name : : "r" (val)); \
+	} \
+	static __inline void _global_##name##_set_nv(int val) { \
+		__asm("movl %0,%%fs:gd_" #name : : "r" (val)); \
+	}
+
+#if defined(SMP) || defined(KLD_MODULE) || defined(ACTUALLY_LKM_NOT_KERNEL)
+/*
+ * The following set of macros works for UP kernel as well, but for maximum
+ * performance we allow the global variables to be accessed directly. On the
+ * other hand, kernel modules should always use these macros to maintain
+ * portability between UP and SMP kernels.
+ */
+#define	curproc		GLOBAL_RVALUE_NV(curproc, struct proc *)
+#define	curpcb		GLOBAL_RVALUE_NV(curpcb, struct pcb *)
+#define	npxproc		GLOBAL_LVALUE(npxproc, struct proc *)
+#define	common_tss	GLOBAL_LVALUE(common_tss, struct i386tss)
+#define	switchtime	GLOBAL_LVALUE(switchtime, struct timeval)
+#define	switchticks	GLOBAL_LVALUE(switchticks, int)
+
+#ifdef VM86
+#define	common_tssd	GLOBAL_LVALUE(common_tssd, struct segment_descriptor)
+#endif
+
+#ifdef USER_LDT
+#define	currentldt	GLOBAL_LVALUE(currentldt, int)
+#endif
+
+#ifdef SMP
+#define	cpuid		GLOBAL_RVALUE(cpuid, u_int)
+#define	other_cpus	GLOBAL_LVALUE(other_cpus, u_int)
+#define	inside_intr	GLOBAL_LVALUE(inside_intr, int)
+#define	prv_CMAP1	GLOBAL_LVALUE(prv_CMAP1, pt_entry_t *)
+#define	prv_CMAP2	GLOBAL_LVALUE(prv_CMAP2, pt_entry_t *)
+#define	prv_CMAP3	GLOBAL_LVALUE(prv_CMAP3, pt_entry_t *)
+#define	prv_PMAP1	GLOBAL_LVALUE(prv_PMAP1, pt_entry_t *)
+#define	prv_CADDR1	GLOBAL_RVALUE(prv_CADDR1, caddr_t)
+#define	prv_CADDR2	GLOBAL_RVALUE(prv_CADDR2, caddr_t)
+#define	prv_CADDR3	GLOBAL_RVALUE(prv_CADDR3, caddr_t)
+#define	prv_PADDR1	GLOBAL_RVALUE(prv_PADDR1, unsigned *)
+#endif
+#endif	/*UP kernel*/
+
+GLOBAL_FUNC(curproc)
+GLOBAL_FUNC(curpcb)
+GLOBAL_FUNC(npxproc)
+GLOBAL_FUNC(common_tss)
+GLOBAL_FUNC(switchtime)
+GLOBAL_FUNC(switchticks)
+
+#ifdef VM86
+GLOBAL_FUNC(common_tssd)
+#endif
+
+#ifdef USER_LDT
+GLOBAL_FUNC(currentldt)
+#endif
+
+#ifdef SMP
+GLOBAL_FUNC(cpuid)
+GLOBAL_FUNC(other_cpus)
+GLOBAL_FUNC(inside_intr)
+GLOBAL_FUNC(prv_CMAP1)
+GLOBAL_FUNC(prv_CMAP2)
+GLOBAL_FUNC(prv_CMAP3)
+GLOBAL_FUNC(prv_PMAP1)
+GLOBAL_FUNC(prv_CADDR1)
+GLOBAL_FUNC(prv_CADDR2)
+GLOBAL_FUNC(prv_CADDR3)
+GLOBAL_FUNC(prv_PADDR1)
+#endif
+
+#define	SET_CURPROC(x)	(_global_curproc_set_nv((int)x))
+
+#endif	/* KERNEL */
+
+#endif	/* !_MACHINE_GLOBALS_H_ */