ia64/linux-2.6.18-xen.hg

view include/asm-i386/desc.h @ 452:c7ed6fe5dca0

kexec: dont initialise regions in reserve_memory()

There is no need to initialise efi_memmap_res and boot_param_res in
reserve_memory() for the initial xen domain as it is done in
machine_kexec_setup_resources() using values from the kexec hypercall.

Signed-off-by: Simon Horman <horms@verge.net.au>
author Keir Fraser <keir.fraser@citrix.com>
date Thu Feb 28 10:55:18 2008 +0000 (2008-02-28)
parents 831230e53067
children
line source
1 #ifndef __ARCH_DESC_H
2 #define __ARCH_DESC_H
4 #include <asm/ldt.h>
5 #include <asm/segment.h>
7 #define CPU_16BIT_STACK_SIZE 1024
9 #ifndef __ASSEMBLY__
11 #include <linux/preempt.h>
12 #include <linux/smp.h>
13 #include <linux/percpu.h>
15 #include <asm/mmu.h>
17 extern struct desc_struct cpu_gdt_table[GDT_ENTRIES];
19 DECLARE_PER_CPU(unsigned char, cpu_16bit_stack[CPU_16BIT_STACK_SIZE]);
21 struct Xgt_desc_struct {
22 unsigned short size;
23 unsigned long address __attribute__((packed));
24 unsigned short pad;
25 } __attribute__ ((packed));
27 extern struct Xgt_desc_struct idt_descr;
28 DECLARE_PER_CPU(struct Xgt_desc_struct, cpu_gdt_descr);
31 static inline struct desc_struct *get_cpu_gdt_table(unsigned int cpu)
32 {
33 return (struct desc_struct *)per_cpu(cpu_gdt_descr, cpu).address;
34 }
36 #define load_TR_desc() __asm__ __volatile__("ltr %w0"::"q" (GDT_ENTRY_TSS*8))
37 #define load_LDT_desc() __asm__ __volatile__("lldt %w0"::"q" (GDT_ENTRY_LDT*8))
39 #define load_gdt(dtr) __asm__ __volatile("lgdt %0"::"m" (*dtr))
40 #define load_idt(dtr) __asm__ __volatile("lidt %0"::"m" (*dtr))
41 #define load_tr(tr) __asm__ __volatile("ltr %0"::"mr" (tr))
42 #define load_ldt(ldt) __asm__ __volatile("lldt %0"::"mr" (ldt))
44 #define store_gdt(dtr) __asm__ ("sgdt %0":"=m" (*dtr))
45 #define store_idt(dtr) __asm__ ("sidt %0":"=m" (*dtr))
46 #define store_tr(tr) __asm__ ("str %0":"=mr" (tr))
47 #define store_ldt(ldt) __asm__ ("sldt %0":"=mr" (ldt))
49 /*
50 * This is the ldt that every process will get unless we need
51 * something other than this.
52 */
53 extern struct desc_struct default_ldt[];
54 extern void set_intr_gate(unsigned int irq, void * addr);
56 #define _set_tssldt_desc(n,addr,limit,type) \
57 __asm__ __volatile__ ("movw %w3,0(%2)\n\t" \
58 "movw %w1,2(%2)\n\t" \
59 "rorl $16,%1\n\t" \
60 "movb %b1,4(%2)\n\t" \
61 "movb %4,5(%2)\n\t" \
62 "movb $0,6(%2)\n\t" \
63 "movb %h1,7(%2)\n\t" \
64 "rorl $16,%1" \
65 : "=m"(*(n)) : "q" (addr), "r"(n), "ir"(limit), "i"(type))
67 static inline void __set_tss_desc(unsigned int cpu, unsigned int entry, void *addr)
68 {
69 _set_tssldt_desc(&get_cpu_gdt_table(cpu)[entry], (int)addr,
70 offsetof(struct tss_struct, __cacheline_filler) - 1, 0x89);
71 }
73 #define set_tss_desc(cpu,addr) __set_tss_desc(cpu, GDT_ENTRY_TSS, addr)
75 static inline void set_ldt_desc(unsigned int cpu, void *addr, unsigned int size)
76 {
77 _set_tssldt_desc(&get_cpu_gdt_table(cpu)[GDT_ENTRY_LDT], (int)addr, ((size << 3)-1), 0x82);
78 }
80 #define LDT_entry_a(info) \
81 ((((info)->base_addr & 0x0000ffff) << 16) | ((info)->limit & 0x0ffff))
83 #define LDT_entry_b(info) \
84 (((info)->base_addr & 0xff000000) | \
85 (((info)->base_addr & 0x00ff0000) >> 16) | \
86 ((info)->limit & 0xf0000) | \
87 (((info)->read_exec_only ^ 1) << 9) | \
88 ((info)->contents << 10) | \
89 (((info)->seg_not_present ^ 1) << 15) | \
90 ((info)->seg_32bit << 22) | \
91 ((info)->limit_in_pages << 23) | \
92 ((info)->useable << 20) | \
93 0x7000)
95 #define LDT_empty(info) (\
96 (info)->base_addr == 0 && \
97 (info)->limit == 0 && \
98 (info)->contents == 0 && \
99 (info)->read_exec_only == 1 && \
100 (info)->seg_32bit == 0 && \
101 (info)->limit_in_pages == 0 && \
102 (info)->seg_not_present == 1 && \
103 (info)->useable == 0 )
105 static inline void write_ldt_entry(void *ldt, int entry, __u32 entry_a, __u32 entry_b)
106 {
107 __u32 *lp = (__u32 *)((char *)ldt + entry*8);
108 *lp = entry_a;
109 *(lp+1) = entry_b;
110 }
112 #if TLS_SIZE != 24
113 # error update this code.
114 #endif
116 static inline void load_TLS(struct thread_struct *t, unsigned int cpu)
117 {
118 #define C(i) get_cpu_gdt_table(cpu)[GDT_ENTRY_TLS_MIN + i] = t->tls_array[i]
119 C(0); C(1); C(2);
120 #undef C
121 }
123 static inline void clear_LDT(void)
124 {
125 int cpu = get_cpu();
127 set_ldt_desc(cpu, &default_ldt[0], 5);
128 load_LDT_desc();
129 put_cpu();
130 }
132 /*
133 * load one particular LDT into the current CPU
134 */
135 static inline void load_LDT_nolock(mm_context_t *pc, int cpu)
136 {
137 void *segments = pc->ldt;
138 int count = pc->size;
140 if (likely(!count)) {
141 segments = &default_ldt[0];
142 count = 5;
143 }
145 set_ldt_desc(cpu, segments, count);
146 load_LDT_desc();
147 }
149 static inline void load_LDT(mm_context_t *pc)
150 {
151 int cpu = get_cpu();
152 load_LDT_nolock(pc, cpu);
153 put_cpu();
154 }
156 static inline unsigned long get_desc_base(unsigned long *desc)
157 {
158 unsigned long base;
159 base = ((desc[0] >> 16) & 0x0000ffff) |
160 ((desc[1] << 16) & 0x00ff0000) |
161 (desc[1] & 0xff000000);
162 return base;
163 }
165 #endif /* !__ASSEMBLY__ */
167 #endif