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Commit 507f90c9 authored by Glauber de Oliveira Costa's avatar Glauber de Oliveira Costa Committed by Ingo Molnar
Browse files

x86: move _set_gate and its users to a common location 



This patch moves _set_gate and its users to desc.h. We can now
use common code for x86_64 and i386.

[ mingo@elte.hu: set_system_gate() fixes for nasty crashes. ]

Signed-off-by: default avatarGlauber de Oliveira Costa <gcosta@redhat.com>
Signed-off-by: default avatarIngo Molnar <mingo@elte.hu>
Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
parent 54cd0eac

arch/x86/kernel/traps_32.c

+0 −34
Original line number Diff line number Diff line
@@ -1102,40 +1102,6 @@ asmlinkage void math_emulate(long arg) 


#endif /* CONFIG_MATH_EMULATION */



/*

 * This needs to use 'idt_table' rather than 'idt', and

 * thus use the _nonmapped_ version of the IDT, as the

 * Pentium F0 0F bugfix can have resulted in the mapped

 * IDT being write-protected.

 */

void set_intr_gate(unsigned int n, void *addr)

{

	_set_gate(n, DESCTYPE_INT, addr, __KERNEL_CS);

}



/*

 * This routine sets up an interrupt gate at directory privilege level 3.

 */

static inline void set_system_intr_gate(unsigned int n, void *addr)

{

	_set_gate(n, DESCTYPE_INT | DESCTYPE_DPL3, addr, __KERNEL_CS);

}



static void __init set_trap_gate(unsigned int n, void *addr)

{

	_set_gate(n, DESCTYPE_TRAP, addr, __KERNEL_CS);

}



static void __init set_system_gate(unsigned int n, void *addr)

{

	_set_gate(n, DESCTYPE_TRAP | DESCTYPE_DPL3, addr, __KERNEL_CS);

}



static void __init set_task_gate(unsigned int n, unsigned int gdt_entry)

{

	_set_gate(n, DESCTYPE_TASK, (void *)0, (gdt_entry<<3));

}





void __init trap_init(void)

{

include/asm-x86/desc.h

+92 −0
Original line number Diff line number Diff line
@@ -33,6 +33,22 @@ extern struct desc_struct cpu_gdt_table[GDT_ENTRIES]; 
extern struct desc_ptr cpu_gdt_descr[];

/* the cpu gdt accessor */

#define get_cpu_gdt_table(x) ((struct desc_struct *)cpu_gdt_descr[x].address)



static inline void pack_gate(gate_desc *gate, unsigned type, unsigned long func,

			     unsigned dpl, unsigned ist, unsigned seg)

{

	gate->offset_low = PTR_LOW(func);

	gate->segment = __KERNEL_CS;

	gate->ist = ist;

	gate->p = 1;

	gate->dpl = dpl;

	gate->zero0 = 0;

	gate->zero1 = 0;

	gate->type = type;

	gate->offset_middle = PTR_MIDDLE(func);

	gate->offset_high = PTR_HIGH(func);

}



#else

struct gdt_page {

	struct desc_struct gdt[GDT_ENTRIES];
@@ -43,6 +59,16 @@ static inline struct desc_struct *get_cpu_gdt_table(unsigned int cpu) 
{

	return per_cpu(gdt_page, cpu).gdt;

}



static inline void pack_gate(gate_desc *gate, unsigned char type,

       unsigned long base, unsigned dpl, unsigned flags, unsigned short seg)



{

	gate->a = (seg << 16) | (base & 0xffff);

	gate->b = (base & 0xffff0000) |

		  (((0x80 | type | (dpl << 5)) & 0xff) << 8);

}



#endif



#ifdef CONFIG_PARAVIRT
@@ -242,6 +268,72 @@ static inline unsigned long get_desc_base(struct desc_struct *desc) 
{

	return desc->base0 | ((desc->base1) << 16) | ((desc->base2) << 24);

}

static inline void _set_gate(int gate, unsigned type, void *addr,

			      unsigned dpl, unsigned ist, unsigned seg)

{

	gate_desc s;

	pack_gate(&s, type, (unsigned long)addr, dpl, ist, seg);

	/*

	 * does not need to be atomic because it is only done once at

	 * setup time

	 */

	write_idt_entry(idt_table, gate, &s);

}



/*

 * This needs to use 'idt_table' rather than 'idt', and

 * thus use the _nonmapped_ version of the IDT, as the

 * Pentium F0 0F bugfix can have resulted in the mapped

 * IDT being write-protected.

 */

static inline void set_intr_gate(unsigned int n, void *addr)

{

	BUG_ON((unsigned)n > 0xFF);

	_set_gate(n, GATE_INTERRUPT, addr, 0, 0, __KERNEL_CS);

}



/*

 * This routine sets up an interrupt gate at directory privilege level 3.

 */

static inline void set_system_intr_gate(unsigned int n, void *addr)

{

	BUG_ON((unsigned)n > 0xFF);

	_set_gate(n, GATE_INTERRUPT, addr, 0x3, 0, __KERNEL_CS);

}



static inline void set_trap_gate(unsigned int n, void *addr)

{

	BUG_ON((unsigned)n > 0xFF);

	_set_gate(n, GATE_TRAP, addr, 0, 0, __KERNEL_CS);

}



static inline void set_system_gate(unsigned int n, void *addr)

{

	BUG_ON((unsigned)n > 0xFF);

#ifdef CONFIG_X86_32

	_set_gate(n, GATE_TRAP, addr, 0x3, 0, __KERNEL_CS);

#else

	_set_gate(n, GATE_INTERRUPT, addr, 0x3, 0, __KERNEL_CS);

#endif

}



static inline void set_task_gate(unsigned int n, unsigned int gdt_entry)

{

	BUG_ON((unsigned)n > 0xFF);

	_set_gate(n, GATE_TASK, (void *)0, 0, 0, (gdt_entry<<3));

}



static inline void set_intr_gate_ist(int n, void *addr, unsigned ist)

{

	BUG_ON((unsigned)n > 0xFF);

	_set_gate(n, GATE_INTERRUPT, addr, 0, ist, __KERNEL_CS);

}



static inline void set_system_gate_ist(int n, void *addr, unsigned ist)

{

	BUG_ON((unsigned)n > 0xFF);

	_set_gate(n, GATE_INTERRUPT, addr, 0x3, ist, __KERNEL_CS);

}



#else

/*

include/asm-x86/desc_32.h

+0 −16
Original line number Diff line number Diff line
@@ -10,22 +10,6 @@ 
#include <linux/preempt.h>

#include <linux/percpu.h>



extern void set_intr_gate(unsigned int irq, void * addr);



static inline void pack_gate(gate_desc *gate,

	unsigned long base, unsigned short seg, unsigned char type, unsigned char flags)

{

	gate->a = (seg << 16) | (base & 0xffff);

	gate->b = (base & 0xffff0000) | ((type & 0xff) << 8) | (flags & 0xff);

}



static inline void _set_gate(int gate, unsigned int type, void *addr, unsigned short seg)

{

	gate_desc g;

	pack_gate(&g, (unsigned long)addr, seg, type, 0);

	write_idt_entry(idt_table, gate, &g);

}



static inline void __set_tss_desc(unsigned int cpu, unsigned int entry, const void *addr)

{

	tss_desc tss;

include/asm-x86/desc_64.h

+0 −45
Original line number Diff line number Diff line
@@ -11,51 +11,6 @@ 


#include <asm/segment.h>



static inline void _set_gate(int gate, unsigned type, unsigned long func,

			     unsigned dpl, unsigned ist)

{

	gate_desc s;



	s.offset_low = PTR_LOW(func);

	s.segment = __KERNEL_CS;

	s.ist = ist;

	s.p = 1;

	s.dpl = dpl;

	s.zero0 = 0;

	s.zero1 = 0;

	s.type = type;

	s.offset_middle = PTR_MIDDLE(func);

	s.offset_high = PTR_HIGH(func);

	/*

	 * does not need to be atomic because it is only done once at

	 * setup time

	 */

	write_idt_entry(idt_table, gate, &s);

}



static inline void set_intr_gate(int nr, void *func)

{

	BUG_ON((unsigned)nr > 0xFF);

	_set_gate(nr, GATE_INTERRUPT, (unsigned long) func, 0, 0);

}



static inline void set_intr_gate_ist(int nr, void *func, unsigned ist)

{

	BUG_ON((unsigned)nr > 0xFF);

	_set_gate(nr, GATE_INTERRUPT, (unsigned long) func, 0, ist);

}



static inline void set_system_gate(int nr, void *func)

{

	BUG_ON((unsigned)nr > 0xFF);

	_set_gate(nr, GATE_INTERRUPT, (unsigned long) func, 3, 0);

}



static inline void set_system_gate_ist(int nr, void *func, unsigned ist)

{

	_set_gate(nr, GATE_INTERRUPT, (unsigned long) func, 3, ist);

}



static inline void set_tss_desc(unsigned cpu, void *addr)

{

	struct desc_struct *d = get_cpu_gdt_table(cpu);

include/asm-x86/desc_defs.h

+1 −4
Original line number Diff line number Diff line
@@ -36,6 +36,7 @@ enum { 
	GATE_INTERRUPT = 0xE,

	GATE_TRAP = 0xF,

	GATE_CALL = 0xC,

	GATE_TASK = 0x5,

};



// 16byte gate
@@ -55,10 +56,6 @@ struct gate_struct64 { 
enum {

	DESC_TSS = 0x9,

	DESC_LDT = 0x2,

	DESCTYPE_TASK = 0x85,   /* present, system, DPL-0, task gate */

	DESCTYPE_INT =  0x8e,   /* present, system, DPL-0, interrupt gate */

	DESCTYPE_TRAP = 0x8f,   /* present, system, DPL-0, trap gate */

	DESCTYPE_DPL3 = 0x60,   /* DPL-3 */

	DESCTYPE_S =	0x10,	/* !system */

};