LXR linux/include/linux/kexec.h

   1#ifndef LINUX_KEXEC_H
   2#define LINUX_KEXEC_H
   3
   4#define IND_DESTINATION_BIT 0
   5#define IND_INDIRECTION_BIT 1
   6#define IND_DONE_BIT        2
   7#define IND_SOURCE_BIT      3
   8
   9#define IND_DESTINATION  (1 << IND_DESTINATION_BIT)
  10#define IND_INDIRECTION  (1 << IND_INDIRECTION_BIT)
  11#define IND_DONE         (1 << IND_DONE_BIT)
  12#define IND_SOURCE       (1 << IND_SOURCE_BIT)
  13#define IND_FLAGS (IND_DESTINATION | IND_INDIRECTION | IND_DONE | IND_SOURCE)
  14
  15#if !defined(__ASSEMBLY__)
  16
  17#include <linux/crash_core.h>
  18#include <asm/io.h>
  19
  20#include <uapi/linux/kexec.h>
  21
  22#ifdef CONFIG_KEXEC_CORE
  23#include <linux/list.h>
  24#include <linux/compat.h>
  25#include <linux/ioport.h>
  26#include <linux/module.h>
  27#include <asm/kexec.h>
  28
  29/* Verify architecture specific macros are defined */
  30
  31#ifndef KEXEC_SOURCE_MEMORY_LIMIT
  32#error KEXEC_SOURCE_MEMORY_LIMIT not defined
  33#endif
  34
  35#ifndef KEXEC_DESTINATION_MEMORY_LIMIT
  36#error KEXEC_DESTINATION_MEMORY_LIMIT not defined
  37#endif
  38
  39#ifndef KEXEC_CONTROL_MEMORY_LIMIT
  40#error KEXEC_CONTROL_MEMORY_LIMIT not defined
  41#endif
  42
  43#ifndef KEXEC_CONTROL_MEMORY_GFP
  44#define KEXEC_CONTROL_MEMORY_GFP (GFP_KERNEL | __GFP_NORETRY)
  45#endif
  46
  47#ifndef KEXEC_CONTROL_PAGE_SIZE
  48#error KEXEC_CONTROL_PAGE_SIZE not defined
  49#endif
  50
  51#ifndef KEXEC_ARCH
  52#error KEXEC_ARCH not defined
  53#endif
  54
  55#ifndef KEXEC_CRASH_CONTROL_MEMORY_LIMIT
  56#define KEXEC_CRASH_CONTROL_MEMORY_LIMIT KEXEC_CONTROL_MEMORY_LIMIT
  57#endif
  58
  59#ifndef KEXEC_CRASH_MEM_ALIGN
  60#define KEXEC_CRASH_MEM_ALIGN PAGE_SIZE
  61#endif
  62
  63#define KEXEC_CORE_NOTE_NAME    CRASH_CORE_NOTE_NAME
  64
  65/*
  66 * This structure is used to hold the arguments that are used when loading
  67 * kernel binaries.
  68 */
  69
  70typedef unsigned long kimage_entry_t;
  71
  72struct kexec_segment {
  73        /*
  74         * This pointer can point to user memory if kexec_load() system
  75         * call is used or will point to kernel memory if
  76         * kexec_file_load() system call is used.
  77         *
  78         * Use ->buf when expecting to deal with user memory and use ->kbuf
  79         * when expecting to deal with kernel memory.
  80         */
  81        union {
  82                void __user *buf;
  83                void *kbuf;
  84        };
  85        size_t bufsz;
  86        unsigned long mem;
  87        size_t memsz;
  88};
  89
  90#ifdef CONFIG_COMPAT
  91struct compat_kexec_segment {
  92        compat_uptr_t buf;
  93        compat_size_t bufsz;
  94        compat_ulong_t mem;     /* User space sees this as a (void *) ... */
  95        compat_size_t memsz;
  96};
  97#endif
  98
  99#ifdef CONFIG_KEXEC_FILE
 100struct purgatory_info {
 101        /* Pointer to elf header of read only purgatory */
 102        Elf_Ehdr *ehdr;
 103
 104        /* Pointer to purgatory sechdrs which are modifiable */
 105        Elf_Shdr *sechdrs;
 106        /*
 107         * Temporary buffer location where purgatory is loaded and relocated
 108         * This memory can be freed post image load
 109         */
 110        void *purgatory_buf;
 111
 112        /* Address where purgatory is finally loaded and is executed from */
 113        unsigned long purgatory_load_addr;
 114};
 115
 116typedef int (kexec_probe_t)(const char *kernel_buf, unsigned long kernel_size);
 117typedef void *(kexec_load_t)(struct kimage *image, char *kernel_buf,
 118                             unsigned long kernel_len, char *initrd,
 119                             unsigned long initrd_len, char *cmdline,
 120                             unsigned long cmdline_len);
 121typedef int (kexec_cleanup_t)(void *loader_data);
 122
 123#ifdef CONFIG_KEXEC_VERIFY_SIG
 124typedef int (kexec_verify_sig_t)(const char *kernel_buf,
 125                                 unsigned long kernel_len);
 126#endif
 127
 128struct kexec_file_ops {
 129        kexec_probe_t *probe;
 130        kexec_load_t *load;
 131        kexec_cleanup_t *cleanup;
 132#ifdef CONFIG_KEXEC_VERIFY_SIG
 133        kexec_verify_sig_t *verify_sig;
 134#endif
 135};
 136
 137/**
 138 * struct kexec_buf - parameters for finding a place for a buffer in memory
 139 * @image:      kexec image in which memory to search.
 140 * @buffer:     Contents which will be copied to the allocated memory.
 141 * @bufsz:      Size of @buffer.
 142 * @mem:        On return will have address of the buffer in memory.
 143 * @memsz:      Size for the buffer in memory.
 144 * @buf_align:  Minimum alignment needed.
 145 * @buf_min:    The buffer can't be placed below this address.
 146 * @buf_max:    The buffer can't be placed above this address.
 147 * @top_down:   Allocate from top of memory.
 148 */
 149struct kexec_buf {
 150        struct kimage *image;
 151        void *buffer;
 152        unsigned long bufsz;
 153        unsigned long mem;
 154        unsigned long memsz;
 155        unsigned long buf_align;
 156        unsigned long buf_min;
 157        unsigned long buf_max;
 158        bool top_down;
 159};
 160
 161int __weak arch_kexec_walk_mem(struct kexec_buf *kbuf,
 162                               int (*func)(u64, u64, void *));
 163extern int kexec_add_buffer(struct kexec_buf *kbuf);
 164int kexec_locate_mem_hole(struct kexec_buf *kbuf);
 165#endif /* CONFIG_KEXEC_FILE */
 166
 167struct kimage {
 168        kimage_entry_t head;
 169        kimage_entry_t *entry;
 170        kimage_entry_t *last_entry;
 171
 172        unsigned long start;
 173        struct page *control_code_page;
 174        struct page *swap_page;
 175        void *vmcoreinfo_data_copy; /* locates in the crash memory */
 176
 177        unsigned long nr_segments;
 178        struct kexec_segment segment[KEXEC_SEGMENT_MAX];
 179
 180        struct list_head control_pages;
 181        struct list_head dest_pages;
 182        struct list_head unusable_pages;
 183
 184        /* Address of next control page to allocate for crash kernels. */
 185        unsigned long control_page;
 186
 187        /* Flags to indicate special processing */
 188        unsigned int type : 1;
 189#define KEXEC_TYPE_DEFAULT 0
 190#define KEXEC_TYPE_CRASH   1
 191        unsigned int preserve_context : 1;
 192        /* If set, we are using file mode kexec syscall */
 193        unsigned int file_mode:1;
 194
 195#ifdef ARCH_HAS_KIMAGE_ARCH
 196        struct kimage_arch arch;
 197#endif
 198
 199#ifdef CONFIG_KEXEC_FILE
 200        /* Additional fields for file based kexec syscall */
 201        void *kernel_buf;
 202        unsigned long kernel_buf_len;
 203
 204        void *initrd_buf;
 205        unsigned long initrd_buf_len;
 206
 207        char *cmdline_buf;
 208        unsigned long cmdline_buf_len;
 209
 210        /* File operations provided by image loader */
 211        struct kexec_file_ops *fops;
 212
 213        /* Image loader handling the kernel can store a pointer here */
 214        void *image_loader_data;
 215
 216        /* Information for loading purgatory */
 217        struct purgatory_info purgatory_info;
 218#endif
 219};
 220
 221/* kexec interface functions */
 222extern void machine_kexec(struct kimage *image);
 223extern int machine_kexec_prepare(struct kimage *image);
 224extern void machine_kexec_cleanup(struct kimage *image);
 225extern asmlinkage long sys_kexec_load(unsigned long entry,
 226                                        unsigned long nr_segments,
 227                                        struct kexec_segment __user *segments,
 228                                        unsigned long flags);
 229extern int kernel_kexec(void);
 230extern struct page *kimage_alloc_control_pages(struct kimage *image,
 231                                                unsigned int order);
 232extern int kexec_load_purgatory(struct kimage *image, unsigned long min,
 233                                unsigned long max, int top_down,
 234                                unsigned long *load_addr);
 235extern int kexec_purgatory_get_set_symbol(struct kimage *image,
 236                                          const char *name, void *buf,
 237                                          unsigned int size, bool get_value);
 238extern void *kexec_purgatory_get_symbol_addr(struct kimage *image,
 239                                             const char *name);
 240extern void __crash_kexec(struct pt_regs *);
 241extern void crash_kexec(struct pt_regs *);
 242int kexec_should_crash(struct task_struct *);
 243int kexec_crash_loaded(void);
 244void crash_save_cpu(struct pt_regs *regs, int cpu);
 245extern int kimage_crash_copy_vmcoreinfo(struct kimage *image);
 246
 247extern struct kimage *kexec_image;
 248extern struct kimage *kexec_crash_image;
 249extern int kexec_load_disabled;
 250
 251#ifndef kexec_flush_icache_page
 252#define kexec_flush_icache_page(page)
 253#endif
 254
 255/* List of defined/legal kexec flags */
 256#ifndef CONFIG_KEXEC_JUMP
 257#define KEXEC_FLAGS    KEXEC_ON_CRASH
 258#else
 259#define KEXEC_FLAGS    (KEXEC_ON_CRASH | KEXEC_PRESERVE_CONTEXT)
 260#endif
 261
 262/* List of defined/legal kexec file flags */
 263#define KEXEC_FILE_FLAGS        (KEXEC_FILE_UNLOAD | KEXEC_FILE_ON_CRASH | \
 264                                 KEXEC_FILE_NO_INITRAMFS)
 265
 266/* Location of a reserved region to hold the crash kernel.
 267 */
 268extern struct resource crashk_res;
 269extern struct resource crashk_low_res;
 270extern note_buf_t __percpu *crash_notes;
 271
 272/* flag to track if kexec reboot is in progress */
 273extern bool kexec_in_progress;
 274
 275int crash_shrink_memory(unsigned long new_size);
 276size_t crash_get_memory_size(void);
 277void crash_free_reserved_phys_range(unsigned long begin, unsigned long end);
 278
 279int __weak arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
 280                                         unsigned long buf_len);
 281void * __weak arch_kexec_kernel_image_load(struct kimage *image);
 282int __weak arch_kimage_file_post_load_cleanup(struct kimage *image);
 283int __weak arch_kexec_kernel_verify_sig(struct kimage *image, void *buf,
 284                                        unsigned long buf_len);
 285int __weak arch_kexec_apply_relocations_add(const Elf_Ehdr *ehdr,
 286                                        Elf_Shdr *sechdrs, unsigned int relsec);
 287int __weak arch_kexec_apply_relocations(const Elf_Ehdr *ehdr, Elf_Shdr *sechdrs,
 288                                        unsigned int relsec);
 289void arch_kexec_protect_crashkres(void);
 290void arch_kexec_unprotect_crashkres(void);
 291
 292#ifndef page_to_boot_pfn
 293static inline unsigned long page_to_boot_pfn(struct page *page)
 294{
 295        return page_to_pfn(page);
 296}
 297#endif
 298
 299#ifndef boot_pfn_to_page
 300static inline struct page *boot_pfn_to_page(unsigned long boot_pfn)
 301{
 302        return pfn_to_page(boot_pfn);
 303}
 304#endif
 305
 306#ifndef phys_to_boot_phys
 307static inline unsigned long phys_to_boot_phys(phys_addr_t phys)
 308{
 309        return phys;
 310}
 311#endif
 312
 313#ifndef boot_phys_to_phys
 314static inline phys_addr_t boot_phys_to_phys(unsigned long boot_phys)
 315{
 316        return boot_phys;
 317}
 318#endif
 319
 320static inline unsigned long virt_to_boot_phys(void *addr)
 321{
 322        return phys_to_boot_phys(__pa((unsigned long)addr));
 323}
 324
 325static inline void *boot_phys_to_virt(unsigned long entry)
 326{
 327        return phys_to_virt(boot_phys_to_phys(entry));
 328}
 329
 330#else /* !CONFIG_KEXEC_CORE */
 331struct pt_regs;
 332struct task_struct;
 333static inline void __crash_kexec(struct pt_regs *regs) { }
 334static inline void crash_kexec(struct pt_regs *regs) { }
 335static inline int kexec_should_crash(struct task_struct *p) { return 0; }
 336static inline int kexec_crash_loaded(void) { return 0; }
 337#define kexec_in_progress false
 338#endif /* CONFIG_KEXEC_CORE */
 339
 340#endif /* !defined(__ASSEBMLY__) */
 341
 342#endif /* LINUX_KEXEC_H */
 343