From b7ee73c6a16e1396333943ce3d3a7bdd8d60255f Mon Sep 17 00:00:00 2001
From: pumnflqv2 <ggdxz77@163.com>
Date: Sun, 26 Jun 2022 21:43:24 +0800
Subject: [PATCH] ADD file via upload

---
 include/asm/system.h | 66 ++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 66 insertions(+)
 create mode 100644 include/asm/system.h

diff --git a/include/asm/system.h b/include/asm/system.h
new file mode 100644
index 0000000..0b5a21d
--- /dev/null
+++ b/include/asm/system.h
@@ -0,0 +1,66 @@
+#define move_to_user_mode() \
+__asm__ ("movl %%esp,%%eax\n\t" \
+	"pushl $0x17\n\t" \
+	"pushl %%eax\n\t" \
+	"pushfl\n\t" \
+	"pushl $0x0f\n\t" \
+	"pushl $1f\n\t" \
+	"iret\n" \
+	"1:\tmovl $0x17,%%eax\n\t" \
+	"movw %%ax,%%ds\n\t" \
+	"movw %%ax,%%es\n\t" \
+	"movw %%ax,%%fs\n\t" \
+	"movw %%ax,%%gs" \
+	:::"ax")
+
+#define sti() __asm__ ("sti"::)
+#define cli() __asm__ ("cli"::)
+#define nop() __asm__ ("nop"::)
+
+#define iret() __asm__ ("iret"::)
+
+#define _set_gate(gate_addr,type,dpl,addr) \
+__asm__ ("movw %%dx,%%ax\n\t" \
+	"movw %0,%%dx\n\t" \
+	"movl %%eax,%1\n\t" \
+	"movl %%edx,%2" \
+	: \
+	: "i" ((short) (0x8000+(dpl<<13)+(type<<8))), \
+	"o" (*((char *) (gate_addr))), \
+	"o" (*(4+(char *) (gate_addr))), \
+	"d" ((char *) (addr)),"a" (0x00080000))
+
+#define set_intr_gate(n,addr) \
+	_set_gate(&idt[n],14,0,addr)
+
+#define set_trap_gate(n,addr) \
+	_set_gate(&idt[n],15,0,addr)
+
+#define set_system_gate(n,addr) \
+	_set_gate(&idt[n],15,3,addr)
+
+#define _set_seg_desc(gate_addr,type,dpl,base,limit) {\
+	*(gate_addr) = ((base) & 0xff000000) | \
+		(((base) & 0x00ff0000)>>16) | \
+		((limit) & 0xf0000) | \
+		((dpl)<<13) | \
+		(0x00408000) | \
+		((type)<<8); \
+	*((gate_addr)+1) = (((base) & 0x0000ffff)<<16) | \
+		((limit) & 0x0ffff); }
+
+#define _set_tssldt_desc(n,addr,type) \
+__asm__ ("movw $104,%1\n\t" \
+	"movw %%ax,%2\n\t" \
+	"rorl $16,%%eax\n\t" \
+	"movb %%al,%3\n\t" \
+	"movb $" type ",%4\n\t" \
+	"movb $0x00,%5\n\t" \
+	"movb %%ah,%6\n\t" \
+	"rorl $16,%%eax" \
+	::"a" (addr), "m" (*(n)), "m" (*(n+2)), "m" (*(n+4)), \
+	 "m" (*(n+5)), "m" (*(n+6)), "m" (*(n+7)) \
+	)
+
+#define set_tss_desc(n,addr) _set_tssldt_desc(((char *) (n)),addr,"0x89")
+#define set_ldt_desc(n,addr) _set_tssldt_desc(((char *) (n)),addr,"0x82")