44 lines
1.3 KiB
C
44 lines
1.3 KiB
C
void enter_user_space(void)
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{
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asm volatile("cli; \
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mov $0x23, %ax; \
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mov %ax, %ds; \
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mov %ax, %es; \
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mov %ax, %fs; \
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mov %ax, %gs; \
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mov %esp, %eax; \
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pushl $0x23; \
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pushl %eax; \
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pushf; \
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popl %eax; \
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orl $0x200, %eax; \
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pushl %eax; \
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pushl $0x1B; \
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push $1f; \
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iret; \
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1: \
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");
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}
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void enter_user_space_v2()
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{
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asm volatile("cli; \
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mov $0x23, %ax; \
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mov %ax, %ds; \
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mov %ax, %es; \
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mov %ax, %fs; \
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mov %ax, %gs; \
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mov %esp, %eax; \
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push $0x23; \
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push %eax; \
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pushf; \
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pop %eax; \
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or $0x200, %eax; \
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push %eax; \
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push $0x1B; \
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push $user_code_entry; \
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iret; \
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user_code_entry: \
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call user_main; \
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");
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} |