Commit 881c2975 authored by Glauber de Oliveira Costa's avatar Glauber de Oliveira Costa Committed by Ingo Molnar
Browse files

x86: unify non-paravirt parts of desc.h 



This patch unifies the non-paravirt part of desc_{32,64}.h into
desc.h. Most of it, is simply common code, that is moved to
the shared header. The only exception is the set_ldt_desc in desc_64.h,
which is changed - included its name - to accomodate for the way
the ldt is set up in i386.

Also, constant definitions used in desc_32.h are moved to desc_defs.h

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 59fbed77

include/asm-x86/desc.h

+64 −1
Original line number Diff line number Diff line
@@ -4,6 +4,7 @@ 
#ifndef __ASSEMBLY__

#include <asm/desc_defs.h>

#include <asm/ldt.h>

#include <asm/mmu.h>



static inline void fill_ldt(struct desc_struct *desc, struct user_desc *info)

{
@@ -23,7 +24,8 @@ static inline void fill_ldt(struct desc_struct *desc, struct user_desc *info) 
	desc->base2 = (info->base_addr & 0xff000000) >> 24;

}



#endif

extern struct desc_ptr idt_descr;

extern gate_desc idt_table[];



#ifdef CONFIG_X86_32

# include "desc_32.h"
@@ -31,4 +33,65 @@ static inline void fill_ldt(struct desc_struct *desc, struct user_desc *info) 
# include "desc_64.h"

#endif



#define _LDT_empty(info) (\

	(info)->base_addr	== 0	&& \

	(info)->limit		== 0	&& \

	(info)->contents	== 0	&& \

	(info)->read_exec_only	== 1	&& \

	(info)->seg_32bit	== 0	&& \

	(info)->limit_in_pages	== 0	&& \

	(info)->seg_not_present	== 1	&& \

	(info)->useable		== 0)



#ifdef CONFIG_X86_64

#define LDT_empty(info) (_LDT_empty(info) && ((info)->lm == 0))

#else

#define LDT_empty(info) (_LDT_empty(info))

#endif



static inline void clear_LDT(void)

{

	set_ldt(NULL, 0);

}



/*

 * load one particular LDT into the current CPU

 */

static inline void load_LDT_nolock(mm_context_t *pc)

{

	set_ldt(pc->ldt, pc->size);

}



static inline void load_LDT(mm_context_t *pc)

{

	preempt_disable();

	load_LDT_nolock(pc);

	preempt_enable();

}



#else

/*

 * GET_DESC_BASE reads the descriptor base of the specified segment.

 *

 * Args:

 *    idx - descriptor index

 *    gdt - GDT pointer

 *    base - 32bit register to which the base will be written

 *    lo_w - lo word of the "base" register

 *    lo_b - lo byte of the "base" register

 *    hi_b - hi byte of the low word of the "base" register

 *

 * Example:

 *    GET_DESC_BASE(GDT_ENTRY_ESPFIX_SS, %ebx, %eax, %ax, %al, %ah)

 *    Will read the base address of GDT_ENTRY_ESPFIX_SS and put it into %eax.

 */

#define GET_DESC_BASE(idx, gdt, base, lo_w, lo_b, hi_b) \

	movb idx*8+4(gdt), lo_b; \

	movb idx*8+7(gdt), hi_b; \

	shll $16, base; \

	movw idx*8+2(gdt), lo_w;





#endif /* __ASSEMBLY__ */



#endif

include/asm-x86/desc_32.h

+0 −58
Original line number Diff line number Diff line
@@ -11,8 +11,6 @@ 
#include <linux/smp.h>

#include <linux/percpu.h>



#include <asm/mmu.h>



struct gdt_page

{

	struct desc_struct gdt[GDT_ENTRIES];
@@ -24,8 +22,6 @@ static inline struct desc_struct *get_cpu_gdt_table(unsigned int cpu) 
	return per_cpu(gdt_page, cpu).gdt;

}



extern struct desc_ptr idt_descr;

extern gate_desc idt_table[];

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



static inline void pack_descriptor(struct desc_struct *desc,
@@ -172,36 +168,6 @@ static inline void __set_tss_desc(unsigned int cpu, unsigned int entry, const vo 


#define set_tss_desc(cpu,addr) __set_tss_desc(cpu, GDT_ENTRY_TSS, addr)



#define LDT_empty(info) (\

	(info)->base_addr	== 0	&& \

	(info)->limit		== 0	&& \

	(info)->contents	== 0	&& \

	(info)->read_exec_only	== 1	&& \

	(info)->seg_32bit	== 0	&& \

	(info)->limit_in_pages	== 0	&& \

	(info)->seg_not_present	== 1	&& \

	(info)->useable		== 0	)



static inline void clear_LDT(void)

{

	set_ldt(NULL, 0);

}



/*

 * load one particular LDT into the current CPU

 */

static inline void load_LDT_nolock(mm_context_t *pc)

{

	set_ldt(pc->ldt, pc->size);

}



static inline void load_LDT(mm_context_t *pc)

{

	preempt_disable();

	load_LDT_nolock(pc);

	preempt_enable();

}



static inline unsigned long get_desc_base(unsigned long *desc)

{

	unsigned long base;
@@ -210,30 +176,6 @@ static inline unsigned long get_desc_base(unsigned long *desc) 
		(desc[1] & 0xff000000);

	return base;

}



#else /* __ASSEMBLY__ */



/*

 * GET_DESC_BASE reads the descriptor base of the specified segment.

 *

 * Args:

 *    idx - descriptor index

 *    gdt - GDT pointer

 *    base - 32bit register to which the base will be written

 *    lo_w - lo word of the "base" register

 *    lo_b - lo byte of the "base" register

 *    hi_b - hi byte of the low word of the "base" register

 *

 * Example:

 *    GET_DESC_BASE(GDT_ENTRY_ESPFIX_SS, %ebx, %eax, %ax, %al, %ah)

 *    Will read the base address of GDT_ENTRY_ESPFIX_SS and put it into %eax.

 */

#define GET_DESC_BASE(idx, gdt, base, lo_w, lo_b, hi_b) \

	movb idx*8+4(gdt), lo_b; \

	movb idx*8+7(gdt), hi_b; \

	shll $16, base; \

	movw idx*8+2(gdt), lo_w;



#endif /* !__ASSEMBLY__ */



#endif

include/asm-x86/desc_64.h

+10 −45
Original line number Diff line number Diff line
@@ -9,16 +9,13 @@ 


#include <linux/string.h>

#include <linux/smp.h>

#include <asm/desc_defs.h>



#include <asm/segment.h>

#include <asm/mmu.h>



extern struct desc_struct cpu_gdt_table[GDT_ENTRIES];



#define load_TR_desc() asm volatile("ltr %w0"::"r" (GDT_ENTRY_TSS*8))

#define load_LDT_desc() asm volatile("lldt %w0"::"r" (GDT_ENTRY_LDT*8))

#define clear_LDT()  asm volatile("lldt %w0"::"r" (0))



static inline unsigned long __store_tr(void)

{
@@ -30,7 +27,6 @@ static inline unsigned long __store_tr(void) 


#define store_tr(tr) (tr) = __store_tr()



extern gate_desc idt_table[];

extern struct desc_ptr cpu_gdt_descr[];



static inline void write_ldt_entry(struct desc_struct *ldt,
@@ -138,22 +134,18 @@ static inline void set_tss_desc(unsigned cpu, void *addr) 
		IO_BITMAP_OFFSET + IO_BITMAP_BYTES + sizeof(unsigned long) - 1);

}



static inline void set_ldt_desc(unsigned cpu, void *addr, int size)

static inline void set_ldt(void *addr, int entries)

{

	if (likely(entries == 0))

		__asm__ __volatile__("lldt %w0"::"q" (0));

	else {

		unsigned cpu = smp_processor_id();



		set_tssldt_descriptor(&get_cpu_gdt_table(cpu)[GDT_ENTRY_LDT],

			     (unsigned long)addr, DESC_LDT, size * 8 - 1);

			     (unsigned long)addr, DESC_LDT, entries * 8 - 1);

		__asm__ __volatile__("lldt %w0"::"q" (GDT_ENTRY_LDT*8));

	}

}



#define LDT_empty(info) (\

	(info)->base_addr	== 0	&& \

	(info)->limit		== 0	&& \

	(info)->contents	== 0	&& \

	(info)->read_exec_only	== 1	&& \

	(info)->seg_32bit	== 0	&& \

	(info)->limit_in_pages	== 0	&& \

	(info)->seg_not_present	== 1	&& \

	(info)->useable		== 0	&& \

	(info)->lm		== 0)



static inline void load_TLS(struct thread_struct *t, unsigned int cpu)

{
@@ -164,32 +156,6 @@ static inline void load_TLS(struct thread_struct *t, unsigned int cpu) 
		gdt[i] = t->tls_array[i];

}



/*

 * load one particular LDT into the current CPU

 */

static inline void load_LDT_nolock(mm_context_t *pc, int cpu)

{

	int count = pc->size;



	if (likely(!count)) {

		clear_LDT();

		return;

	}



	set_ldt_desc(cpu, pc->ldt, count);

	load_LDT_desc();

}



static inline void load_LDT(mm_context_t *pc)

{

	int cpu = get_cpu();



	load_LDT_nolock(pc, cpu);

	put_cpu();

}



extern struct desc_ptr idt_descr;



static inline unsigned long get_desc_base(const void *ptr)

{

	const u32 *desc = ptr;
@@ -199,7 +165,6 @@ static inline unsigned long get_desc_base(const void *ptr) 
		(desc[1] & 0xff000000);

	return base;

}



#endif /* !__ASSEMBLY__ */



#endif

include/asm-x86/mmu_context_64.h

+2 −2
Original line number Diff line number Diff line
@@ -43,7 +43,7 @@ static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next, 
		load_cr3(next->pgd);



		if (unlikely(next->context.ldt != prev->context.ldt)) 

			load_LDT_nolock(&next->context, cpu);

			load_LDT_nolock(&next->context);

	}

#ifdef CONFIG_SMP

	else {
@@ -56,7 +56,7 @@ static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next, 
			 * to make sure to use no freed page tables.

			 */

			load_cr3(next->pgd);

			load_LDT_nolock(&next->context, cpu);

			load_LDT_nolock(&next->context);

		}

	}

#endif

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