Include missing linux/slab.h inclusions
[linux-3.10.git] / arch / x86 / kernel / machine_kexec_32.c
1 /*
2  * handle transition of Linux booting another kernel
3  * Copyright (C) 2002-2005 Eric Biederman  <ebiederm@xmission.com>
4  *
5  * This source code is licensed under the GNU General Public License,
6  * Version 2.  See the file COPYING for more details.
7  */
8
9 #include <linux/mm.h>
10 #include <linux/kexec.h>
11 #include <linux/delay.h>
12 #include <linux/init.h>
13 #include <linux/numa.h>
14 #include <linux/ftrace.h>
15 #include <linux/suspend.h>
16 #include <linux/gfp.h>
17 #include <linux/io.h>
18
19 #include <asm/pgtable.h>
20 #include <asm/pgalloc.h>
21 #include <asm/tlbflush.h>
22 #include <asm/mmu_context.h>
23 #include <asm/apic.h>
24 #include <asm/cpufeature.h>
25 #include <asm/desc.h>
26 #include <asm/cacheflush.h>
27 #include <asm/debugreg.h>
28
29 static void set_idt(void *newidt, __u16 limit)
30 {
31         struct desc_ptr curidt;
32
33         /* ia32 supports unaliged loads & stores */
34         curidt.size    = limit;
35         curidt.address = (unsigned long)newidt;
36
37         load_idt(&curidt);
38 }
39
40
41 static void set_gdt(void *newgdt, __u16 limit)
42 {
43         struct desc_ptr curgdt;
44
45         /* ia32 supports unaligned loads & stores */
46         curgdt.size    = limit;
47         curgdt.address = (unsigned long)newgdt;
48
49         load_gdt(&curgdt);
50 }
51
52 static void load_segments(void)
53 {
54 #define __STR(X) #X
55 #define STR(X) __STR(X)
56
57         __asm__ __volatile__ (
58                 "\tljmp $"STR(__KERNEL_CS)",$1f\n"
59                 "\t1:\n"
60                 "\tmovl $"STR(__KERNEL_DS)",%%eax\n"
61                 "\tmovl %%eax,%%ds\n"
62                 "\tmovl %%eax,%%es\n"
63                 "\tmovl %%eax,%%fs\n"
64                 "\tmovl %%eax,%%gs\n"
65                 "\tmovl %%eax,%%ss\n"
66                 : : : "eax", "memory");
67 #undef STR
68 #undef __STR
69 }
70
71 static void machine_kexec_free_page_tables(struct kimage *image)
72 {
73         free_page((unsigned long)image->arch.pgd);
74 #ifdef CONFIG_X86_PAE
75         free_page((unsigned long)image->arch.pmd0);
76         free_page((unsigned long)image->arch.pmd1);
77 #endif
78         free_page((unsigned long)image->arch.pte0);
79         free_page((unsigned long)image->arch.pte1);
80 }
81
82 static int machine_kexec_alloc_page_tables(struct kimage *image)
83 {
84         image->arch.pgd = (pgd_t *)get_zeroed_page(GFP_KERNEL);
85 #ifdef CONFIG_X86_PAE
86         image->arch.pmd0 = (pmd_t *)get_zeroed_page(GFP_KERNEL);
87         image->arch.pmd1 = (pmd_t *)get_zeroed_page(GFP_KERNEL);
88 #endif
89         image->arch.pte0 = (pte_t *)get_zeroed_page(GFP_KERNEL);
90         image->arch.pte1 = (pte_t *)get_zeroed_page(GFP_KERNEL);
91         if (!image->arch.pgd ||
92 #ifdef CONFIG_X86_PAE
93             !image->arch.pmd0 || !image->arch.pmd1 ||
94 #endif
95             !image->arch.pte0 || !image->arch.pte1) {
96                 machine_kexec_free_page_tables(image);
97                 return -ENOMEM;
98         }
99         return 0;
100 }
101
102 static void machine_kexec_page_table_set_one(
103         pgd_t *pgd, pmd_t *pmd, pte_t *pte,
104         unsigned long vaddr, unsigned long paddr)
105 {
106         pud_t *pud;
107
108         pgd += pgd_index(vaddr);
109 #ifdef CONFIG_X86_PAE
110         if (!(pgd_val(*pgd) & _PAGE_PRESENT))
111                 set_pgd(pgd, __pgd(__pa(pmd) | _PAGE_PRESENT));
112 #endif
113         pud = pud_offset(pgd, vaddr);
114         pmd = pmd_offset(pud, vaddr);
115         if (!(pmd_val(*pmd) & _PAGE_PRESENT))
116                 set_pmd(pmd, __pmd(__pa(pte) | _PAGE_TABLE));
117         pte = pte_offset_kernel(pmd, vaddr);
118         set_pte(pte, pfn_pte(paddr >> PAGE_SHIFT, PAGE_KERNEL_EXEC));
119 }
120
121 static void machine_kexec_prepare_page_tables(struct kimage *image)
122 {
123         void *control_page;
124         pmd_t *pmd = NULL;
125
126         control_page = page_address(image->control_code_page);
127 #ifdef CONFIG_X86_PAE
128         pmd = image->arch.pmd0;
129 #endif
130         machine_kexec_page_table_set_one(
131                 image->arch.pgd, pmd, image->arch.pte0,
132                 (unsigned long)control_page, __pa(control_page));
133 #ifdef CONFIG_X86_PAE
134         pmd = image->arch.pmd1;
135 #endif
136         machine_kexec_page_table_set_one(
137                 image->arch.pgd, pmd, image->arch.pte1,
138                 __pa(control_page), __pa(control_page));
139 }
140
141 /*
142  * A architecture hook called to validate the
143  * proposed image and prepare the control pages
144  * as needed.  The pages for KEXEC_CONTROL_PAGE_SIZE
145  * have been allocated, but the segments have yet
146  * been copied into the kernel.
147  *
148  * Do what every setup is needed on image and the
149  * reboot code buffer to allow us to avoid allocations
150  * later.
151  *
152  * - Make control page executable.
153  * - Allocate page tables
154  * - Setup page tables
155  */
156 int machine_kexec_prepare(struct kimage *image)
157 {
158         int error;
159
160         set_pages_x(image->control_code_page, 1);
161         error = machine_kexec_alloc_page_tables(image);
162         if (error)
163                 return error;
164         machine_kexec_prepare_page_tables(image);
165         return 0;
166 }
167
168 /*
169  * Undo anything leftover by machine_kexec_prepare
170  * when an image is freed.
171  */
172 void machine_kexec_cleanup(struct kimage *image)
173 {
174         set_pages_nx(image->control_code_page, 1);
175         machine_kexec_free_page_tables(image);
176 }
177
178 /*
179  * Do not allocate memory (or fail in any way) in machine_kexec().
180  * We are past the point of no return, committed to rebooting now.
181  */
182 void machine_kexec(struct kimage *image)
183 {
184         unsigned long page_list[PAGES_NR];
185         void *control_page;
186         int save_ftrace_enabled;
187         asmlinkage unsigned long
188                 (*relocate_kernel_ptr)(unsigned long indirection_page,
189                                        unsigned long control_page,
190                                        unsigned long start_address,
191                                        unsigned int has_pae,
192                                        unsigned int preserve_context);
193
194 #ifdef CONFIG_KEXEC_JUMP
195         if (image->preserve_context)
196                 save_processor_state();
197 #endif
198
199         save_ftrace_enabled = __ftrace_enabled_save();
200
201         /* Interrupts aren't acceptable while we reboot */
202         local_irq_disable();
203         hw_breakpoint_disable();
204
205         if (image->preserve_context) {
206 #ifdef CONFIG_X86_IO_APIC
207                 /*
208                  * We need to put APICs in legacy mode so that we can
209                  * get timer interrupts in second kernel. kexec/kdump
210                  * paths already have calls to disable_IO_APIC() in
211                  * one form or other. kexec jump path also need
212                  * one.
213                  */
214                 disable_IO_APIC();
215 #endif
216         }
217
218         control_page = page_address(image->control_code_page);
219         memcpy(control_page, relocate_kernel, KEXEC_CONTROL_CODE_MAX_SIZE);
220
221         relocate_kernel_ptr = control_page;
222         page_list[PA_CONTROL_PAGE] = __pa(control_page);
223         page_list[VA_CONTROL_PAGE] = (unsigned long)control_page;
224         page_list[PA_PGD] = __pa(image->arch.pgd);
225
226         if (image->type == KEXEC_TYPE_DEFAULT)
227                 page_list[PA_SWAP_PAGE] = (page_to_pfn(image->swap_page)
228                                                 << PAGE_SHIFT);
229
230         /*
231          * The segment registers are funny things, they have both a
232          * visible and an invisible part.  Whenever the visible part is
233          * set to a specific selector, the invisible part is loaded
234          * with from a table in memory.  At no other time is the
235          * descriptor table in memory accessed.
236          *
237          * I take advantage of this here by force loading the
238          * segments, before I zap the gdt with an invalid value.
239          */
240         load_segments();
241         /*
242          * The gdt & idt are now invalid.
243          * If you want to load them you must set up your own idt & gdt.
244          */
245         set_gdt(phys_to_virt(0), 0);
246         set_idt(phys_to_virt(0), 0);
247
248         /* now call it */
249         image->start = relocate_kernel_ptr((unsigned long)image->head,
250                                            (unsigned long)page_list,
251                                            image->start, cpu_has_pae,
252                                            image->preserve_context);
253
254 #ifdef CONFIG_KEXEC_JUMP
255         if (image->preserve_context)
256                 restore_processor_state();
257 #endif
258
259         __ftrace_enabled_restore(save_ftrace_enabled);
260 }
261
262 void arch_crash_save_vmcoreinfo(void)
263 {
264 #ifdef CONFIG_NUMA
265         VMCOREINFO_SYMBOL(node_data);
266         VMCOREINFO_LENGTH(node_data, MAX_NUMNODES);
267 #endif
268 #ifdef CONFIG_X86_PAE
269         VMCOREINFO_CONFIG(X86_PAE);
270 #endif
271 }
272