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#ifndef __ARCH_DESC_H
#define __ARCH_DESC_H
#include <asm/ldt.h>
#include <asm/segment.h>
#define CPU_16BIT_STACK_SIZE 1024
#ifndef __ASSEMBLY__
#include <linux/preempt.h>
#include <linux/smp.h>
#include <linux/percpu.h>
#include <asm/mmu.h>
extern struct desc_struct cpu_gdt_table[GDT_ENTRIES];
DECLARE_PER_CPU(unsigned char, cpu_16bit_stack[CPU_16BIT_STACK_SIZE]);
struct Xgt_desc_struct {
unsigned short size;
unsigned long address __attribute__((packed));
unsigned short pad;
} __attribute__ ((packed));
extern struct Xgt_desc_struct idt_descr;
DECLARE_PER_CPU(struct Xgt_desc_struct, cpu_gdt_descr);
static inline struct desc_struct *get_cpu_gdt_table(unsigned int cpu)
{
return (struct desc_struct *)per_cpu(cpu_gdt_descr, cpu).address;
}
/*
* This is the ldt that every process will get unless we need
* something other than this.
*/
extern struct desc_struct default_ldt[];
extern struct desc_struct idt_table[];
extern void set_intr_gate(unsigned int irq, void * addr);
static inline void pack_descriptor(__u32 *a, __u32 *b,
unsigned long base, unsigned long limit, unsigned char type, unsigned char flags)
{
*a = ((base & 0xffff) << 16) | (limit & 0xffff);
*b = (base & 0xff000000) | ((base & 0xff0000) >> 16) |
(limit & 0x000f0000) | ((type & 0xff) << 8) | ((flags & 0xf) << 20);
}
static inline void pack_gate(__u32 *a, __u32 *b,
unsigned long base, unsigned short seg, unsigned char type, unsigned char flags)
{
*a = (seg << 16) | (base & 0xffff);
*b = (base & 0xffff0000) | ((type & 0xff) << 8) | (flags & 0xff);
}
#define DESCTYPE_LDT 0x82 /* present, system, DPL-0, LDT */
#define DESCTYPE_TSS 0x89 /* present, system, DPL-0, 32-bit TSS */
#define DESCTYPE_TASK 0x85 /* present, system, DPL-0, task gate */
#define DESCTYPE_INT 0x8e /* present, system, DPL-0, interrupt gate */
#define DESCTYPE_TRAP 0x8f /* present, system, DPL-0, trap gate */
#define DESCTYPE_DPL3 0x60 /* DPL-3 */
#define DESCTYPE_S 0x10 /* !system */
#define load_TR_desc() __asm__ __volatile__("ltr %w0"::"q" (GDT_ENTRY_TSS*8))
#define load_LDT_desc() __asm__ __volatile__("lldt %w0"::"q" (GDT_ENTRY_LDT*8))
#define load_gdt(dtr) __asm__ __volatile("lgdt %0"::"m" (*dtr))
#define load_idt(dtr) __asm__ __volatile("lidt %0"::"m" (*dtr))
#define load_tr(tr) __asm__ __volatile("ltr %0"::"m" (tr))
#define load_ldt(ldt) __asm__ __volatile("lldt %0"::"m" (ldt))
#define store_gdt(dtr) __asm__ ("sgdt %0":"=m" (*dtr))
#define store_idt(dtr) __asm__ ("sidt %0":"=m" (*dtr))
#define store_tr(tr) __asm__ ("str %0":"=m" (tr))
#define store_ldt(ldt) __asm__ ("sldt %0":"=m" (ldt))
#if TLS_SIZE != 24
# error update this code.
#endif
static inline void load_TLS(struct thread_struct *t, unsigned int cpu)
{
#define C(i) get_cpu_gdt_table(cpu)[GDT_ENTRY_TLS_MIN + i] = t->tls_array[i]
C(0); C(1); C(2);
#undef C
}
static inline void write_dt_entry(void *dt, int entry, __u32 entry_a, __u32 entry_b)
{
__u32 *lp = (__u32 *)((char *)dt + entry*8);
*lp = entry_a;
*(lp+1) = entry_b;
}
#define write_ldt_entry(dt, entry, a, b) write_dt_entry(dt, entry, a, b)
#define write_gdt_entry(dt, entry, a, b) write_dt_entry(dt, entry, a, b)
#define write_idt_entry(dt, entry, a, b) write_dt_entry(dt, entry, a, b)
static inline void _set_gate(int gate, unsigned int type, void *addr, unsigned short seg)
{
__u32 a, b;
pack_gate(&a, &b, (unsigned long)addr, seg, type, 0);
write_idt_entry(idt_table, gate, a, b);
}
static inline void __set_tss_desc(unsigned int cpu, unsigned int entry, const void *addr)
{
__u32 a, b;
pack_descriptor(&a, &b, (unsigned long)addr,
offsetof(struct tss_struct, __cacheline_filler) - 1,
DESCTYPE_TSS, 0);
write_gdt_entry(get_cpu_gdt_table(cpu), entry, a, b);
}
static inline void set_ldt_desc(unsigned int cpu, void *addr, unsigned int entries)
{
__u32 a, b;
pack_descriptor(&a, &b, (unsigned long)addr,
entries * sizeof(struct desc_struct) - 1,
DESCTYPE_LDT, 0);
write_gdt_entry(get_cpu_gdt_table(cpu), GDT_ENTRY_LDT, a, b);
}
#define set_tss_desc(cpu,addr) __set_tss_desc(cpu, GDT_ENTRY_TSS, addr)
#define LDT_entry_a(info) \
((((info)->base_addr & 0x0000ffff) << 16) | ((info)->limit & 0x0ffff))
#define LDT_entry_b(info) \
(((info)->base_addr & 0xff000000) | \
(((info)->base_addr & 0x00ff0000) >> 16) | \
((info)->limit & 0xf0000) | \
(((info)->read_exec_only ^ 1) << 9) | \
((info)->contents << 10) | \
(((info)->seg_not_present ^ 1) << 15) | \
((info)->seg_32bit << 22) | \
((info)->limit_in_pages << 23) | \
((info)->useable << 20) | \
0x7000)
#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)
{
int cpu = get_cpu();
set_ldt_desc(cpu, &default_ldt[0], 5);
load_LDT_desc();
put_cpu();
}
/*
* load one particular LDT into the current CPU
*/
static inline void load_LDT_nolock(mm_context_t *pc, int cpu)
{
void *segments = pc->ldt;
int count = pc->size;
if (likely(!count)) {
segments = &default_ldt[0];
count = 5;
}
set_ldt_desc(cpu, segments, count);
load_LDT_desc();
}
static inline void load_LDT(mm_context_t *pc)
{
int cpu = get_cpu();
load_LDT_nolock(pc, cpu);
put_cpu();
}
static inline unsigned long get_desc_base(unsigned long *desc)
{
unsigned long base;
base = ((desc[0] >> 16) & 0x0000ffff) |
((desc[1] << 16) & 0x00ff0000) |
(desc[1] & 0xff000000);
return base;
}
#endif /* !__ASSEMBLY__ */
#endif
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