inc/x86.h

@@ -3,10 +3,6 @@
 
 #include <inc/types.h>
 
-#define MSR_IA32_SYSENTER_CS 0x174
-#define MSR_IA32_SYSENTER_EIP 0x176
-#define MSR_IA32_SYSENTER_ESP 0x175
-
 static inline void
 breakpoint(void)
 {
@@ -265,19 +261,4 @@ xchg(volatile uint32_t *addr, uint32_t newval)
 	return result;
 }
 
-static inline void
-write_msr(uint32_t reg, uint32_t low, uint32_t high) {
-	asm volatile("wrmsr\n\t"
-			:: "c" (reg), "a" (low), "d" (high));
-}
-
-static inline void
-read_msr(uint32_t reg, uint32_t* low, uint32_t* high) {
-	uint32_t eax, edx;
-	asm volatile("rdmsr\n\t"
-			: "=a" (eax), "=d" (edx) : "c" (reg));
-	*low = eax;
-	*high = edx;
-}
-
 #endif /* !JOS_INC_X86_H */

kern/init.c

@@ -3,7 +3,6 @@
 #include <inc/stdio.h>
 #include <inc/string.h>
 #include <inc/assert.h>
-#include <inc/x86.h>
 
 #include <kern/monitor.h>
 #include <kern/console.h>
@@ -12,7 +11,6 @@
 #include <kern/env.h>
 #include <kern/trap.h>
 
-void sysenter_handler();
 
 void
 i386_init(void)
@@ -36,10 +34,6 @@ i386_init(void)
 		"\33[34m" "r"
 		"\33[0m"  " Works!" "\n");
 
-	write_msr(MSR_IA32_SYSENTER_EIP, (uint32_t) sysenter_handler, 0);
-	write_msr(MSR_IA32_SYSENTER_ESP, KSTACKTOP, 0);
-	write_msr(MSR_IA32_SYSENTER_CS, GD_KT, 0);
-
 	// Lab 2 memory management initialization functions
 	mem_init();
 

kern/trapentry.S

@@ -43,21 +43,6 @@
 
 .text
 
-.globl sysenter_handler
-sysenter_handler:
-	push %ebp // holds env's stack pointer
-	push %esi // holds the env's return addr
-	push %edi
-	push %ebx
-	push %ecx
-	push %edx
-	push %eax
-	call syscall
-	add $0x14, %esp
-	pop %edx
-	pop %ecx
-	sysexit
-	
 /*
  * Lab 3: Your code here for generating entry points for the different traps.
  */

lib/syscall.c

@@ -2,7 +2,6 @@
 
 #include <inc/syscall.h>
 #include <inc/lib.h>
-#include <inc/x86.h>
 
 static inline int32_t
 syscall(int num, int check, uint32_t a1, uint32_t a2, uint32_t a3, uint32_t a4, uint32_t a5)
@@ -38,30 +37,16 @@ syscall(int num, int check, uint32_t a1, uint32_t a2, uint32_t a3, uint32_t a4,
 	return ret;
 }
 
-int32_t
-fast_syscall(int num, uint32_t a1, uint32_t a2, uint32_t a3, uint32_t a4) {
-	asm volatile(
-			"push %%ebp\n\t"
-			"mov %%esp, %%ebp\n\t"
-			"lea syscall_ret_%=, %%esi\n\t"
-			"sysenter\n\t"
-			"syscall_ret_%=: pop %%ebp\n\t"
-			: "+a" (num)
-			: "d" (a1), "c" (a2), "b" (a3), "D" (a4)
-			: "esi");
-	return num;
-}
-
 void
 sys_cputs(const char *s, size_t len)
 {
-	fast_syscall(SYS_cputs, (uint32_t)s, len, 0, 0);
+	syscall(SYS_cputs, 0, (uint32_t)s, len, 0, 0, 0);
 }
 
 int
 sys_cgetc(void)
 {
-	return fast_syscall(SYS_cgetc, 0, 0, 0, 0);
+	return syscall(SYS_cgetc, 0, 0, 0, 0, 0, 0);
 }
 
 int