Re: [PATCH 2/8] Move privileged processor operations to the subarch layer

[Chris Wright <chrisw@osdl.org>]

* Zachary Amsden (zach@vmware.com) wrote:
> i386 Transparent Paravirtualization Subarch Patch #2
> 
> This change encapsulates CPUID and debug register accessors and moves
> them into the sub-architecture layer. 

This one looks to be a superset of Xen version:

--- linux-2.6.12-xen0-arch.orig/include/asm-i386/processor.h
+++ linux-2.6.12-xen0-arch/include/asm-i386/processor.h
@@ -203,10 +203,6 @@ static inline unsigned int cpuid_edx(uns
 	return edx;
 }
 
-#define load_cr3(pgdir) \
-	asm volatile("movl %0,%%cr3": :"r" (__pa(pgdir)))
-
-
 /*
  * Intel CPU features in CR4
  */
@@ -230,15 +226,7 @@ static inline unsigned int cpuid_edx(uns
  */
 extern unsigned long mmu_cr4_features;
 
-static inline void set_in_cr4 (unsigned long mask)
-{
-	mmu_cr4_features |= mask;
-	__asm__("movl %%cr4,%%eax\n\t"
-		"orl %0,%%eax\n\t"
-		"movl %%eax,%%cr4\n"
-		: : "irg" (mask)
-		:"ax");
-}
+#include <mach_processor.h>
 
 static inline void clear_in_cr4 (unsigned long mask)
 {
@@ -453,6 +441,7 @@ struct thread_struct {
 	unsigned long		v86flags, v86mask, saved_esp0;
 	unsigned int		saved_fs, saved_gs;
 /* IO permissions */
+	unsigned long	io_pl;
 	unsigned long	*io_bitmap_ptr;
 /* max allowed port in the bitmap, in bytes: */
 	unsigned long	io_bitmap_max;
@@ -487,6 +476,7 @@ static inline void load_esp0(struct tss_
 		tss->ss1 = thread->sysenter_cs;
 		wrmsr(MSR_IA32_SYSENTER_CS, thread->sysenter_cs, 0);
 	}
+	mach_load_esp0(tss, thread);
 }
 
 #define start_thread(regs, new_eip, new_esp) do {		\
@@ -500,14 +490,6 @@ static inline void load_esp0(struct tss_
 	regs->esp = new_esp;					\
 } while (0)
 
-/*
- * This special macro can be used to load a debugging register
- */
-#define loaddebug(thread,register) \
-               __asm__("movl %0,%%db" #register  \
-                       : /* no output */ \
-                       :"r" ((thread)->debugreg[register]))
-
 /* Forward declaration, a strange C thing */
 struct task_struct;
 struct mm_struct;
--- /dev/null
+++ linux-2.6.12-xen0-arch/include/asm-i386/mach-default/mach_processor.h
@@ -0,0 +1,27 @@
+#ifndef __ASM_MACH_PROCESSOR_H
+#define __ASM_MACH_PROCESSOR_H
+
+#define load_cr3(pgdir) \
+	asm volatile("movl %0,%%cr3": :"r" (__pa(pgdir)))
+
+static inline void set_in_cr4 (unsigned long mask)
+{
+	mmu_cr4_features |= mask;
+	__asm__("movl %%cr4,%%eax\n\t"
+		"orl %0,%%eax\n\t"
+		"movl %%eax,%%cr4\n"
+		: : "irg" (mask)
+		:"ax");
+}
+
+#define mach_load_esp0(tss, thread) do {} while(0)
+
+/*
+ * This special macro can be used to load a debugging register
+ */
+#define loaddebug(thread,register) \
+               __asm__("movl %0,%%db" #register  \
+                       : /* no output */ \
+                       :"r" ((thread)->debugreg[register]))
+
+#endif