x86, asm: Clean up desc.h a bit

I have looked at this file and found it rather ugly - improve
readability a bit. No change in functionality.

Link: http://lkml.kernel.org/n/tip-incpt6y26yd8586idx65t9ll@git.kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Ingo Molnar 2011-05-27 09:29:32 +02:00
parent e9cdd343a5
commit 9a3865b185

View File

@ -4,30 +4,33 @@
#include <asm/desc_defs.h> #include <asm/desc_defs.h>
#include <asm/ldt.h> #include <asm/ldt.h>
#include <asm/mmu.h> #include <asm/mmu.h>
#include <linux/smp.h> #include <linux/smp.h>
static inline void fill_ldt(struct desc_struct *desc, static inline void fill_ldt(struct desc_struct *desc, const struct user_desc *info)
const struct user_desc *info)
{ {
desc->limit0 = info->limit & 0x0ffff; desc->limit0 = info->limit & 0x0ffff;
desc->base0 = info->base_addr & 0x0000ffff;
desc->base1 = (info->base_addr & 0x00ff0000) >> 16; desc->base0 = (info->base_addr & 0x0000ffff);
desc->type = (info->read_exec_only ^ 1) << 1; desc->base1 = (info->base_addr & 0x00ff0000) >> 16;
desc->type |= info->contents << 2;
desc->s = 1; desc->type = (info->read_exec_only ^ 1) << 1;
desc->dpl = 0x3; desc->type |= info->contents << 2;
desc->p = info->seg_not_present ^ 1;
desc->limit = (info->limit & 0xf0000) >> 16; desc->s = 1;
desc->avl = info->useable; desc->dpl = 0x3;
desc->d = info->seg_32bit; desc->p = info->seg_not_present ^ 1;
desc->g = info->limit_in_pages; desc->limit = (info->limit & 0xf0000) >> 16;
desc->base2 = (info->base_addr & 0xff000000) >> 24; desc->avl = info->useable;
desc->d = info->seg_32bit;
desc->g = info->limit_in_pages;
desc->base2 = (info->base_addr & 0xff000000) >> 24;
/* /*
* Don't allow setting of the lm bit. It is useless anyway * Don't allow setting of the lm bit. It is useless anyway
* because 64bit system calls require __USER_CS: * because 64bit system calls require __USER_CS:
*/ */
desc->l = 0; desc->l = 0;
} }
extern struct desc_ptr idt_descr; extern struct desc_ptr idt_descr;
@ -36,6 +39,7 @@ extern gate_desc idt_table[];
struct gdt_page { struct gdt_page {
struct desc_struct gdt[GDT_ENTRIES]; struct desc_struct gdt[GDT_ENTRIES];
} __attribute__((aligned(PAGE_SIZE))); } __attribute__((aligned(PAGE_SIZE)));
DECLARE_PER_CPU_PAGE_ALIGNED(struct gdt_page, gdt_page); DECLARE_PER_CPU_PAGE_ALIGNED(struct gdt_page, gdt_page);
static inline struct desc_struct *get_cpu_gdt_table(unsigned int cpu) static inline struct desc_struct *get_cpu_gdt_table(unsigned int cpu)
@ -48,16 +52,16 @@ static inline struct desc_struct *get_cpu_gdt_table(unsigned int cpu)
static inline void pack_gate(gate_desc *gate, unsigned type, unsigned long func, static inline void pack_gate(gate_desc *gate, unsigned type, unsigned long func,
unsigned dpl, unsigned ist, unsigned seg) unsigned dpl, unsigned ist, unsigned seg)
{ {
gate->offset_low = PTR_LOW(func); gate->offset_low = PTR_LOW(func);
gate->segment = __KERNEL_CS; gate->segment = __KERNEL_CS;
gate->ist = ist; gate->ist = ist;
gate->p = 1; gate->p = 1;
gate->dpl = dpl; gate->dpl = dpl;
gate->zero0 = 0; gate->zero0 = 0;
gate->zero1 = 0; gate->zero1 = 0;
gate->type = type; gate->type = type;
gate->offset_middle = PTR_MIDDLE(func); gate->offset_middle = PTR_MIDDLE(func);
gate->offset_high = PTR_HIGH(func); gate->offset_high = PTR_HIGH(func);
} }
#else #else
@ -66,8 +70,7 @@ static inline void pack_gate(gate_desc *gate, unsigned char type,
unsigned short seg) unsigned short seg)
{ {
gate->a = (seg << 16) | (base & 0xffff); gate->a = (seg << 16) | (base & 0xffff);
gate->b = (base & 0xffff0000) | gate->b = (base & 0xffff0000) | (((0x80 | type | (dpl << 5)) & 0xff) << 8);
(((0x80 | type | (dpl << 5)) & 0xff) << 8);
} }
#endif #endif
@ -75,31 +78,29 @@ static inline void pack_gate(gate_desc *gate, unsigned char type,
static inline int desc_empty(const void *ptr) static inline int desc_empty(const void *ptr)
{ {
const u32 *desc = ptr; const u32 *desc = ptr;
return !(desc[0] | desc[1]); return !(desc[0] | desc[1]);
} }
#ifdef CONFIG_PARAVIRT #ifdef CONFIG_PARAVIRT
#include <asm/paravirt.h> #include <asm/paravirt.h>
#else #else
#define load_TR_desc() native_load_tr_desc() #define load_TR_desc() native_load_tr_desc()
#define load_gdt(dtr) native_load_gdt(dtr) #define load_gdt(dtr) native_load_gdt(dtr)
#define load_idt(dtr) native_load_idt(dtr) #define load_idt(dtr) native_load_idt(dtr)
#define load_tr(tr) asm volatile("ltr %0"::"m" (tr)) #define load_tr(tr) asm volatile("ltr %0"::"m" (tr))
#define load_ldt(ldt) asm volatile("lldt %0"::"m" (ldt)) #define load_ldt(ldt) asm volatile("lldt %0"::"m" (ldt))
#define store_gdt(dtr) native_store_gdt(dtr) #define store_gdt(dtr) native_store_gdt(dtr)
#define store_idt(dtr) native_store_idt(dtr) #define store_idt(dtr) native_store_idt(dtr)
#define store_tr(tr) (tr = native_store_tr()) #define store_tr(tr) (tr = native_store_tr())
#define load_TLS(t, cpu) native_load_tls(t, cpu) #define load_TLS(t, cpu) native_load_tls(t, cpu)
#define set_ldt native_set_ldt #define set_ldt native_set_ldt
#define write_ldt_entry(dt, entry, desc) \ #define write_ldt_entry(dt, entry, desc) native_write_ldt_entry(dt, entry, desc)
native_write_ldt_entry(dt, entry, desc) #define write_gdt_entry(dt, entry, desc, type) native_write_gdt_entry(dt, entry, desc, type)
#define write_gdt_entry(dt, entry, desc, type) \ #define write_idt_entry(dt, entry, g) native_write_idt_entry(dt, entry, g)
native_write_gdt_entry(dt, entry, desc, type)
#define write_idt_entry(dt, entry, g) \
native_write_idt_entry(dt, entry, g)
static inline void paravirt_alloc_ldt(struct desc_struct *ldt, unsigned entries) static inline void paravirt_alloc_ldt(struct desc_struct *ldt, unsigned entries)
{ {
@ -112,33 +113,27 @@ static inline void paravirt_free_ldt(struct desc_struct *ldt, unsigned entries)
#define store_ldt(ldt) asm("sldt %0" : "=m"(ldt)) #define store_ldt(ldt) asm("sldt %0" : "=m"(ldt))
static inline void native_write_idt_entry(gate_desc *idt, int entry, static inline void native_write_idt_entry(gate_desc *idt, int entry, const gate_desc *gate)
const gate_desc *gate)
{ {
memcpy(&idt[entry], gate, sizeof(*gate)); memcpy(&idt[entry], gate, sizeof(*gate));
} }
static inline void native_write_ldt_entry(struct desc_struct *ldt, int entry, static inline void native_write_ldt_entry(struct desc_struct *ldt, int entry, const void *desc)
const void *desc)
{ {
memcpy(&ldt[entry], desc, 8); memcpy(&ldt[entry], desc, 8);
} }
static inline void native_write_gdt_entry(struct desc_struct *gdt, int entry, static inline void
const void *desc, int type) native_write_gdt_entry(struct desc_struct *gdt, int entry, const void *desc, int type)
{ {
unsigned int size; unsigned int size;
switch (type) { switch (type) {
case DESC_TSS: case DESC_TSS: size = sizeof(tss_desc); break;
size = sizeof(tss_desc); case DESC_LDT: size = sizeof(ldt_desc); break;
break; default: size = sizeof(*gdt); break;
case DESC_LDT:
size = sizeof(ldt_desc);
break;
default:
size = sizeof(struct desc_struct);
break;
} }
memcpy(&gdt[entry], desc, size); memcpy(&gdt[entry], desc, size);
} }
@ -154,20 +149,21 @@ static inline void pack_descriptor(struct desc_struct *desc, unsigned long base,
} }
static inline void set_tssldt_descriptor(void *d, unsigned long addr, static inline void set_tssldt_descriptor(void *d, unsigned long addr, unsigned type, unsigned size)
unsigned type, unsigned size)
{ {
#ifdef CONFIG_X86_64 #ifdef CONFIG_X86_64
struct ldttss_desc64 *desc = d; struct ldttss_desc64 *desc = d;
memset(desc, 0, sizeof(*desc)); memset(desc, 0, sizeof(*desc));
desc->limit0 = size & 0xFFFF;
desc->base0 = PTR_LOW(addr); desc->limit0 = size & 0xFFFF;
desc->base1 = PTR_MIDDLE(addr) & 0xFF; desc->base0 = PTR_LOW(addr);
desc->type = type; desc->base1 = PTR_MIDDLE(addr) & 0xFF;
desc->p = 1; desc->type = type;
desc->limit1 = (size >> 16) & 0xF; desc->p = 1;
desc->base2 = (PTR_MIDDLE(addr) >> 8) & 0xFF; desc->limit1 = (size >> 16) & 0xF;
desc->base3 = PTR_HIGH(addr); desc->base2 = (PTR_MIDDLE(addr) >> 8) & 0xFF;
desc->base3 = PTR_HIGH(addr);
#else #else
pack_descriptor((struct desc_struct *)d, addr, size, 0x80 | type, 0); pack_descriptor((struct desc_struct *)d, addr, size, 0x80 | type, 0);
#endif #endif
@ -237,14 +233,16 @@ static inline void native_store_idt(struct desc_ptr *dtr)
static inline unsigned long native_store_tr(void) static inline unsigned long native_store_tr(void)
{ {
unsigned long tr; unsigned long tr;
asm volatile("str %0":"=r" (tr)); asm volatile("str %0":"=r" (tr));
return tr; return tr;
} }
static inline void native_load_tls(struct thread_struct *t, unsigned int cpu) 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); struct desc_struct *gdt = get_cpu_gdt_table(cpu);
unsigned int i;
for (i = 0; i < GDT_ENTRY_TLS_ENTRIES; i++) for (i = 0; i < GDT_ENTRY_TLS_ENTRIES; i++)
gdt[GDT_ENTRY_TLS_MIN + i] = t->tls_array[i]; gdt[GDT_ENTRY_TLS_MIN + i] = t->tls_array[i];
@ -313,6 +311,7 @@ static inline void _set_gate(int gate, unsigned type, void *addr,
unsigned dpl, unsigned ist, unsigned seg) unsigned dpl, unsigned ist, unsigned seg)
{ {
gate_desc s; gate_desc s;
pack_gate(&s, type, (unsigned long)addr, dpl, ist, seg); pack_gate(&s, type, (unsigned long)addr, dpl, ist, seg);
/* /*
* does not need to be atomic because it is only done once at * does not need to be atomic because it is only done once at
@ -343,8 +342,9 @@ static inline void alloc_system_vector(int vector)
set_bit(vector, used_vectors); set_bit(vector, used_vectors);
if (first_system_vector > vector) if (first_system_vector > vector)
first_system_vector = vector; first_system_vector = vector;
} else } else {
BUG(); BUG();
}
} }
static inline void alloc_intr_gate(unsigned int n, void *addr) static inline void alloc_intr_gate(unsigned int n, void *addr)