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#ifndef __ARCH_DESC_H
#define __ARCH_DESC_H
#include <asm/ldt.h>
#include <asm/segment.h>
#include <asm/desc_defs.h>
#ifndef __ASSEMBLY__
#include <linux/preempt.h>
#include <linux/smp.h>
#include <linux/percpu.h>
#include <asm/mmu.h>
struct gdt_page
{
struct desc_struct gdt[GDT_ENTRIES];
} __attribute__((aligned(PAGE_SIZE)));
DECLARE_PER_CPU(struct gdt_page, gdt_page);
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,
unsigned long base, unsigned long limit, unsigned char type, unsigned char flags)
{
desc->a = ((base & 0xffff) << 16) | (limit & 0xffff);
desc->b = (base & 0xff000000) | ((base & 0xff0000) >> 16) |
(limit & 0x000f0000) | ((type & 0xff) << 8) | ((flags & 0xf) << 20);
desc->p = 1;
}
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);
}
#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 */
#ifdef CONFIG_PARAVIRT
#include <asm/paravirt.h>
#else
#define load_TR_desc() native_load_tr_desc()
#define load_gdt(dtr) native_load_gdt(dtr)
#define load_idt(dtr) native_load_idt(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) native_store_gdt(dtr)
#define store_idt(dtr) native_store_idt(dtr)
#define store_tr(tr) (tr = native_store_tr())
#define store_ldt(ldt) __asm__ ("sldt %0":"=m" (ldt))
#define load_TLS(t, cpu) native_load_tls(t, cpu)
#define set_ldt native_set_ldt
#define write_ldt_entry(dt, entry, a, b) write_dt_entry(dt, entry, a, b)
#define write_gdt_entry(dt, entry, desc, type) \
native_write_gdt_entry(dt, entry, desc, type)
#define write_idt_entry(dt, entry, g) native_write_idt_entry(dt, entry, g)
#endif
static inline void native_write_idt_entry(gate_desc *idt, int entry,
const gate_desc *gate)
{
memcpy(&idt[entry], gate, sizeof(*gate));
}
static inline void native_write_gdt_entry(struct desc_struct *gdt, int entry,
const void *desc, int type)
{
memcpy(&gdt[entry], desc, sizeof(struct desc_struct));
}
static inline void write_dt_entry(struct desc_struct *dt,
int entry, u32 entry_low, u32 entry_high)
{
dt[entry].a = entry_low;
dt[entry].b = entry_high;
}
static inline void native_set_ldt(const void *addr, unsigned int entries)
{
if (likely(entries == 0))
__asm__ __volatile__("lldt %w0"::"q" (0));
else {
unsigned cpu = smp_processor_id();
ldt_desc ldt;
pack_descriptor(&ldt, (unsigned long)addr,
entries * sizeof(struct desc_struct) - 1,
DESC_LDT, 0);
write_gdt_entry(get_cpu_gdt_table(cpu), GDT_ENTRY_LDT,
&ldt, DESC_LDT);
__asm__ __volatile__("lldt %w0"::"q" (GDT_ENTRY_LDT*8));
}
}
static inline void native_load_tr_desc(void)
{
asm volatile("ltr %w0"::"q" (GDT_ENTRY_TSS*8));
}
static inline void native_load_gdt(const struct desc_ptr *dtr)
{
asm volatile("lgdt %0"::"m" (*dtr));
}
static inline void native_load_idt(const struct desc_ptr *dtr)
{
asm volatile("lidt %0"::"m" (*dtr));
}
static inline void native_store_gdt(struct desc_ptr *dtr)
{
asm ("sgdt %0":"=m" (*dtr));
}
static inline void native_store_idt(struct desc_ptr *dtr)
{
asm ("sidt %0":"=m" (*dtr));
}
static inline unsigned long native_store_tr(void)
{
unsigned long tr;
asm ("str %0":"=r" (tr));
return tr;
}
static inline void native_load_tls(struct thread_struct *t, unsigned int cpu)
{
unsigned int i;
struct desc_struct *gdt = get_cpu_gdt_table(cpu);
for (i = 0; i < GDT_ENTRY_TLS_ENTRIES; i++)
gdt[GDT_ENTRY_TLS_MIN + i] = t->tls_array[i];
}
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;
pack_descriptor(&tss, (unsigned long)addr,
offsetof(struct tss_struct, __cacheline_filler) - 1,
DESC_TSS, 0);
write_gdt_entry(get_cpu_gdt_table(cpu), entry, &tss, DESC_TSS);
}
#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;
base = ((desc[0] >> 16) & 0x0000ffff) |
((desc[1] << 16) & 0x00ff0000) |
(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
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