1#ifndef _ASM_X86_KEXEC_H
2#define _ASM_X86_KEXEC_H
3
4#ifdef CONFIG_X86_32
5# define PA_CONTROL_PAGE	0
6# define VA_CONTROL_PAGE	1
7# define PA_PGD			2
8# define PA_SWAP_PAGE		3
9# define PAGES_NR		4
10#else
11# define PA_CONTROL_PAGE	0
12# define VA_CONTROL_PAGE	1
13# define PA_TABLE_PAGE		2
14# define PA_SWAP_PAGE		3
15# define PAGES_NR		4
16#endif
17
18# define KEXEC_CONTROL_CODE_MAX_SIZE	2048
19
20#ifndef __ASSEMBLY__
21
22#include <linux/string.h>
23
24#include <asm/page.h>
25#include <asm/ptrace.h>
26#include <asm/bootparam.h>
27
28struct kimage;
29
30/*
31 * KEXEC_SOURCE_MEMORY_LIMIT maximum page get_free_page can return.
32 * I.e. Maximum page that is mapped directly into kernel memory,
33 * and kmap is not required.
34 *
35 * So far x86_64 is limited to 40 physical address bits.
36 */
37#ifdef CONFIG_X86_32
38/* Maximum physical address we can use pages from */
39# define KEXEC_SOURCE_MEMORY_LIMIT (-1UL)
40/* Maximum address we can reach in physical address mode */
41# define KEXEC_DESTINATION_MEMORY_LIMIT (-1UL)
42/* Maximum address we can use for the control code buffer */
43# define KEXEC_CONTROL_MEMORY_LIMIT TASK_SIZE
44
45# define KEXEC_CONTROL_PAGE_SIZE	4096
46
47/* The native architecture */
48# define KEXEC_ARCH KEXEC_ARCH_386
49
50/* We can also handle crash dumps from 64 bit kernel. */
51# define vmcore_elf_check_arch_cross(x) ((x)->e_machine == EM_X86_64)
52#else
53/* Maximum physical address we can use pages from */
54# define KEXEC_SOURCE_MEMORY_LIMIT      (MAXMEM-1)
55/* Maximum address we can reach in physical address mode */
56# define KEXEC_DESTINATION_MEMORY_LIMIT (MAXMEM-1)
57/* Maximum address we can use for the control pages */
58# define KEXEC_CONTROL_MEMORY_LIMIT     (MAXMEM-1)
59
60/* Allocate one page for the pdp and the second for the code */
61# define KEXEC_CONTROL_PAGE_SIZE  (4096UL + 4096UL)
62
63/* The native architecture */
64# define KEXEC_ARCH KEXEC_ARCH_X86_64
65#endif
66
67/* Memory to backup during crash kdump */
68#define KEXEC_BACKUP_SRC_START	(0UL)
69#define KEXEC_BACKUP_SRC_END	(640 * 1024UL)	/* 640K */
70
71/*
72 * CPU does not save ss and sp on stack if execution is already
73 * running in kernel mode at the time of NMI occurrence. This code
74 * fixes it.
75 */
76static inline void crash_fixup_ss_esp(struct pt_regs *newregs,
77				      struct pt_regs *oldregs)
78{
79#ifdef CONFIG_X86_32
80	newregs->sp = (unsigned long)&(oldregs->sp);
81	asm volatile("xorl %%eax, %%eax\n\t"
82		     "movw %%ss, %%ax\n\t"
83		     :"=a"(newregs->ss));
84#endif
85}
86
87/*
88 * This function is responsible for capturing register states if coming
89 * via panic otherwise just fix up the ss and sp if coming via kernel
90 * mode exception.
91 */
92static inline void crash_setup_regs(struct pt_regs *newregs,
93				    struct pt_regs *oldregs)
94{
95	if (oldregs) {
96		memcpy(newregs, oldregs, sizeof(*newregs));
97		crash_fixup_ss_esp(newregs, oldregs);
98	} else {
99#ifdef CONFIG_X86_32
100		asm volatile("movl %%ebx,%0" : "=m"(newregs->bx));
101		asm volatile("movl %%ecx,%0" : "=m"(newregs->cx));
102		asm volatile("movl %%edx,%0" : "=m"(newregs->dx));
103		asm volatile("movl %%esi,%0" : "=m"(newregs->si));
104		asm volatile("movl %%edi,%0" : "=m"(newregs->di));
105		asm volatile("movl %%ebp,%0" : "=m"(newregs->bp));
106		asm volatile("movl %%eax,%0" : "=m"(newregs->ax));
107		asm volatile("movl %%esp,%0" : "=m"(newregs->sp));
108		asm volatile("movl %%ss, %%eax;" :"=a"(newregs->ss));
109		asm volatile("movl %%cs, %%eax;" :"=a"(newregs->cs));
110		asm volatile("movl %%ds, %%eax;" :"=a"(newregs->ds));
111		asm volatile("movl %%es, %%eax;" :"=a"(newregs->es));
112		asm volatile("pushfl; popl %0" :"=m"(newregs->flags));
113#else
114		asm volatile("movq %%rbx,%0" : "=m"(newregs->bx));
115		asm volatile("movq %%rcx,%0" : "=m"(newregs->cx));
116		asm volatile("movq %%rdx,%0" : "=m"(newregs->dx));
117		asm volatile("movq %%rsi,%0" : "=m"(newregs->si));
118		asm volatile("movq %%rdi,%0" : "=m"(newregs->di));
119		asm volatile("movq %%rbp,%0" : "=m"(newregs->bp));
120		asm volatile("movq %%rax,%0" : "=m"(newregs->ax));
121		asm volatile("movq %%rsp,%0" : "=m"(newregs->sp));
122		asm volatile("movq %%r8,%0" : "=m"(newregs->r8));
123		asm volatile("movq %%r9,%0" : "=m"(newregs->r9));
124		asm volatile("movq %%r10,%0" : "=m"(newregs->r10));
125		asm volatile("movq %%r11,%0" : "=m"(newregs->r11));
126		asm volatile("movq %%r12,%0" : "=m"(newregs->r12));
127		asm volatile("movq %%r13,%0" : "=m"(newregs->r13));
128		asm volatile("movq %%r14,%0" : "=m"(newregs->r14));
129		asm volatile("movq %%r15,%0" : "=m"(newregs->r15));
130		asm volatile("movl %%ss, %%eax;" :"=a"(newregs->ss));
131		asm volatile("movl %%cs, %%eax;" :"=a"(newregs->cs));
132		asm volatile("pushfq; popq %0" :"=m"(newregs->flags));
133#endif
134		newregs->ip = (unsigned long)current_text_addr();
135	}
136}
137
138#ifdef CONFIG_X86_32
139asmlinkage unsigned long
140relocate_kernel(unsigned long indirection_page,
141		unsigned long control_page,
142		unsigned long start_address,
143		unsigned int has_pae,
144		unsigned int preserve_context);
145#else
146unsigned long
147relocate_kernel(unsigned long indirection_page,
148		unsigned long page_list,
149		unsigned long start_address,
150		unsigned int preserve_context);
151#endif
152
153#define ARCH_HAS_KIMAGE_ARCH
154
155#ifdef CONFIG_X86_32
156struct kimage_arch {
157	pgd_t *pgd;
158#ifdef CONFIG_X86_PAE
159	pmd_t *pmd0;
160	pmd_t *pmd1;
161#endif
162	pte_t *pte0;
163	pte_t *pte1;
164};
165#else
166struct kimage_arch {
167	pud_t *pud;
168	pmd_t *pmd;
169	pte_t *pte;
170	/* Details of backup region */
171	unsigned long backup_src_start;
172	unsigned long backup_src_sz;
173
174	/* Physical address of backup segment */
175	unsigned long backup_load_addr;
176
177	/* Core ELF header buffer */
178	void *elf_headers;
179	unsigned long elf_headers_sz;
180	unsigned long elf_load_addr;
181};
182#endif /* CONFIG_X86_32 */
183
184#ifdef CONFIG_X86_64
185/*
186 * Number of elements and order of elements in this structure should match
187 * with the ones in arch/x86/purgatory/entry64.S. If you make a change here
188 * make an appropriate change in purgatory too.
189 */
190struct kexec_entry64_regs {
191	uint64_t rax;
192	uint64_t rcx;
193	uint64_t rdx;
194	uint64_t rbx;
195	uint64_t rsp;
196	uint64_t rbp;
197	uint64_t rsi;
198	uint64_t rdi;
199	uint64_t r8;
200	uint64_t r9;
201	uint64_t r10;
202	uint64_t r11;
203	uint64_t r12;
204	uint64_t r13;
205	uint64_t r14;
206	uint64_t r15;
207	uint64_t rip;
208};
209#endif
210
211typedef void crash_vmclear_fn(void);
212extern crash_vmclear_fn __rcu *crash_vmclear_loaded_vmcss;
213
214#endif /* __ASSEMBLY__ */
215
216#endif /* _ASM_X86_KEXEC_H */
217