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 <asm/io.h>
  18
  19#include <uapi/linux/kexec.h>
  20
  21#ifdef CONFIG_KEXEC_CORE
  22#include <linux/list.h>
  23#include <linux/linkage.h>
  24#include <linux/compat.h>
  25#include <linux/ioport.h>
  26#include <linux/elfcore.h>
  27#include <linux/elf.h>
  28#include <linux/module.h>
  29#include <asm/kexec.h>
  30
  31/* Verify architecture specific macros are defined */
  32
  33#ifndef KEXEC_SOURCE_MEMORY_LIMIT
  34#error KEXEC_SOURCE_MEMORY_LIMIT not defined
  35#endif
  36
  37#ifndef KEXEC_DESTINATION_MEMORY_LIMIT
  38#error KEXEC_DESTINATION_MEMORY_LIMIT not defined
  39#endif
  40
  41#ifndef KEXEC_CONTROL_MEMORY_LIMIT
  42#error KEXEC_CONTROL_MEMORY_LIMIT not defined
  43#endif
  44
  45#ifndef KEXEC_CONTROL_MEMORY_GFP
  46#define KEXEC_CONTROL_MEMORY_GFP (GFP_KERNEL | __GFP_NORETRY)
  47#endif
  48
  49#ifndef KEXEC_CONTROL_PAGE_SIZE
  50#error KEXEC_CONTROL_PAGE_SIZE not defined
  51#endif
  52
  53#ifndef KEXEC_ARCH
  54#error KEXEC_ARCH not defined
  55#endif
  56
  57#ifndef KEXEC_CRASH_CONTROL_MEMORY_LIMIT
  58#define KEXEC_CRASH_CONTROL_MEMORY_LIMIT KEXEC_CONTROL_MEMORY_LIMIT
  59#endif
  60
  61#ifndef KEXEC_CRASH_MEM_ALIGN
  62#define KEXEC_CRASH_MEM_ALIGN PAGE_SIZE
  63#endif
  64
  65#define KEXEC_NOTE_HEAD_BYTES ALIGN(sizeof(struct elf_note), 4)
  66#define KEXEC_CORE_NOTE_NAME "CORE"
  67#define KEXEC_CORE_NOTE_NAME_BYTES ALIGN(sizeof(KEXEC_CORE_NOTE_NAME), 4)
  68#define KEXEC_CORE_NOTE_DESC_BYTES ALIGN(sizeof(struct elf_prstatus), 4)
  69/*
  70 * The per-cpu notes area is a list of notes terminated by a "NULL"
  71 * note header.  For kdump, the code in vmcore.c runs in the context
  72 * of the second kernel to combine them into one note.
  73 */
  74#ifndef KEXEC_NOTE_BYTES
  75#define KEXEC_NOTE_BYTES ( (KEXEC_NOTE_HEAD_BYTES * 2) +                \
  76                            KEXEC_CORE_NOTE_NAME_BYTES +                \
  77                            KEXEC_CORE_NOTE_DESC_BYTES )
  78#endif
  79
  80/*
  81 * This structure is used to hold the arguments that are used when loading
  82 * kernel binaries.
  83 */
  84
  85typedef unsigned long kimage_entry_t;
  86
  87struct kexec_segment {
  88        /*
  89         * This pointer can point to user memory if kexec_load() system
  90         * call is used or will point to kernel memory if
  91         * kexec_file_load() system call is used.
  92         *
  93         * Use ->buf when expecting to deal with user memory and use ->kbuf
  94         * when expecting to deal with kernel memory.
  95         */
  96        union {
  97                void __user *buf;
  98                void *kbuf;
  99        };
 100        size_t bufsz;
 101        unsigned long mem;
 102        size_t memsz;
 103};
 104
 105#ifdef CONFIG_COMPAT
 106struct compat_kexec_segment {
 107        compat_uptr_t buf;
 108        compat_size_t bufsz;
 109        compat_ulong_t mem;     /* User space sees this as a (void *) ... */
 110        compat_size_t memsz;
 111};
 112#endif
 113
 114#ifdef CONFIG_KEXEC_FILE
 115struct purgatory_info {
 116        /* Pointer to elf header of read only purgatory */
 117        Elf_Ehdr *ehdr;
 118
 119        /* Pointer to purgatory sechdrs which are modifiable */
 120        Elf_Shdr *sechdrs;
 121        /*
 122         * Temporary buffer location where purgatory is loaded and relocated
 123         * This memory can be freed post image load
 124         */
 125        void *purgatory_buf;
 126
 127        /* Address where purgatory is finally loaded and is executed from */
 128        unsigned long purgatory_load_addr;
 129};
 130
 131typedef int (kexec_probe_t)(const char *kernel_buf, unsigned long kernel_size);
 132typedef void *(kexec_load_t)(struct kimage *image, char *kernel_buf,
 133                             unsigned long kernel_len, char *initrd,
 134                             unsigned long initrd_len, char *cmdline,
 135                             unsigned long cmdline_len);
 136typedef int (kexec_cleanup_t)(void *loader_data);
 137
 138#ifdef CONFIG_KEXEC_VERIFY_SIG
 139typedef int (kexec_verify_sig_t)(const char *kernel_buf,
 140                                 unsigned long kernel_len);
 141#endif
 142
 143struct kexec_file_ops {
 144        kexec_probe_t *probe;
 145        kexec_load_t *load;
 146        kexec_cleanup_t *cleanup;
 147#ifdef CONFIG_KEXEC_VERIFY_SIG
 148        kexec_verify_sig_t *verify_sig;
 149#endif
 150};
 151
 152/**
 153 * struct kexec_buf - parameters for finding a place for a buffer in memory
 154 * @image:      kexec image in which memory to search.
 155 * @buffer:     Contents which will be copied to the allocated memory.
 156 * @bufsz:      Size of @buffer.
 157 * @mem:        On return will have address of the buffer in memory.
 158 * @memsz:      Size for the buffer in memory.
 159 * @buf_align:  Minimum alignment needed.
 160 * @buf_min:    The buffer can't be placed below this address.
 161 * @buf_max:    The buffer can't be placed above this address.
 162 * @top_down:   Allocate from top of memory.
 163 */
 164struct kexec_buf {
 165        struct kimage *image;
 166        void *buffer;
 167        unsigned long bufsz;
 168        unsigned long mem;
 169        unsigned long memsz;
 170        unsigned long buf_align;
 171        unsigned long buf_min;
 172        unsigned long buf_max;
 173        bool top_down;
 174};
 175
 176int __weak arch_kexec_walk_mem(struct kexec_buf *kbuf,
 177                               int (*func)(u64, u64, void *));
 178extern int kexec_add_buffer(struct kexec_buf *kbuf);
 179int kexec_locate_mem_hole(struct kexec_buf *kbuf);
 180#endif /* CONFIG_KEXEC_FILE */
 181
 182struct kimage {
 183        kimage_entry_t head;
 184        kimage_entry_t *entry;
 185        kimage_entry_t *last_entry;
 186
 187        unsigned long start;
 188        struct page *control_code_page;
 189        struct page *swap_page;
 190
 191        unsigned long nr_segments;
 192        struct kexec_segment segment[KEXEC_SEGMENT_MAX];
 193
 194        struct list_head control_pages;
 195        struct list_head dest_pages;
 196        struct list_head unusable_pages;
 197
 198        /* Address of next control page to allocate for crash kernels. */
 199        unsigned long control_page;
 200
 201        /* Flags to indicate special processing */
 202        unsigned int type : 1;
 203#define KEXEC_TYPE_DEFAULT 0
 204#define KEXEC_TYPE_CRASH   1
 205        unsigned int preserve_context : 1;
 206        /* If set, we are using file mode kexec syscall */
 207        unsigned int file_mode:1;
 208
 209#ifdef ARCH_HAS_KIMAGE_ARCH
 210        struct kimage_arch arch;
 211#endif
 212
 213#ifdef CONFIG_KEXEC_FILE
 214        /* Additional fields for file based kexec syscall */
 215        void *kernel_buf;
 216        unsigned long kernel_buf_len;
 217
 218        void *initrd_buf;
 219        unsigned long initrd_buf_len;
 220
 221        char *cmdline_buf;
 222        unsigned long cmdline_buf_len;
 223
 224        /* File operations provided by image loader */
 225        struct kexec_file_ops *fops;
 226
 227        /* Image loader handling the kernel can store a pointer here */
 228        void *image_loader_data;
 229
 230        /* Information for loading purgatory */
 231        struct purgatory_info purgatory_info;
 232#endif
 233};
 234
 235/* kexec interface functions */
 236extern void machine_kexec(struct kimage *image);
 237extern int machine_kexec_prepare(struct kimage *image);
 238extern void machine_kexec_cleanup(struct kimage *image);
 239extern asmlinkage long sys_kexec_load(unsigned long entry,
 240                                        unsigned long nr_segments,
 241                                        struct kexec_segment __user *segments,
 242                                        unsigned long flags);
 243extern int kernel_kexec(void);
 244extern struct page *kimage_alloc_control_pages(struct kimage *image,
 245                                                unsigned int order);
 246extern int kexec_load_purgatory(struct kimage *image, unsigned long min,
 247                                unsigned long max, int top_down,
 248                                unsigned long *load_addr);
 249extern int kexec_purgatory_get_set_symbol(struct kimage *image,
 250                                          const char *name, void *buf,
 251                                          unsigned int size, bool get_value);
 252extern void *kexec_purgatory_get_symbol_addr(struct kimage *image,
 253                                             const char *name);
 254extern void __crash_kexec(struct pt_regs *);
 255extern void crash_kexec(struct pt_regs *);
 256int kexec_should_crash(struct task_struct *);
 257int kexec_crash_loaded(void);
 258void crash_save_cpu(struct pt_regs *regs, int cpu);
 259void crash_save_vmcoreinfo(void);
 260void arch_crash_save_vmcoreinfo(void);
 261__printf(1, 2)
 262void vmcoreinfo_append_str(const char *fmt, ...);
 263phys_addr_t paddr_vmcoreinfo_note(void);
 264
 265#define VMCOREINFO_OSRELEASE(value) \
 266        vmcoreinfo_append_str("OSRELEASE=%s\n", value)
 267#define VMCOREINFO_PAGESIZE(value) \
 268        vmcoreinfo_append_str("PAGESIZE=%ld\n", value)
 269#define VMCOREINFO_SYMBOL(name) \
 270        vmcoreinfo_append_str("SYMBOL(%s)=%lx\n", #name, (unsigned long)&name)
 271#define VMCOREINFO_SIZE(name) \
 272        vmcoreinfo_append_str("SIZE(%s)=%lu\n", #name, \
 273                              (unsigned long)sizeof(name))
 274#define VMCOREINFO_STRUCT_SIZE(name) \
 275        vmcoreinfo_append_str("SIZE(%s)=%lu\n", #name, \
 276                              (unsigned long)sizeof(struct name))
 277#define VMCOREINFO_OFFSET(name, field) \
 278        vmcoreinfo_append_str("OFFSET(%s.%s)=%lu\n", #name, #field, \
 279                              (unsigned long)offsetof(struct name, field))
 280#define VMCOREINFO_LENGTH(name, value) \
 281        vmcoreinfo_append_str("LENGTH(%s)=%lu\n", #name, (unsigned long)value)
 282#define VMCOREINFO_NUMBER(name) \
 283        vmcoreinfo_append_str("NUMBER(%s)=%ld\n", #name, (long)name)
 284#define VMCOREINFO_CONFIG(name) \
 285        vmcoreinfo_append_str("CONFIG_%s=y\n", #name)
 286
 287extern struct kimage *kexec_image;
 288extern struct kimage *kexec_crash_image;
 289extern int kexec_load_disabled;
 290
 291#ifndef kexec_flush_icache_page
 292#define kexec_flush_icache_page(page)
 293#endif
 294
 295/* List of defined/legal kexec flags */
 296#ifndef CONFIG_KEXEC_JUMP
 297#define KEXEC_FLAGS    KEXEC_ON_CRASH
 298#else
 299#define KEXEC_FLAGS    (KEXEC_ON_CRASH | KEXEC_PRESERVE_CONTEXT)
 300#endif
 301
 302/* List of defined/legal kexec file flags */
 303#define KEXEC_FILE_FLAGS        (KEXEC_FILE_UNLOAD | KEXEC_FILE_ON_CRASH | \
 304                                 KEXEC_FILE_NO_INITRAMFS)
 305
 306#define VMCOREINFO_BYTES           (4096)
 307#define VMCOREINFO_NOTE_NAME       "VMCOREINFO"
 308#define VMCOREINFO_NOTE_NAME_BYTES ALIGN(sizeof(VMCOREINFO_NOTE_NAME), 4)
 309#define VMCOREINFO_NOTE_SIZE       (KEXEC_NOTE_HEAD_BYTES*2 + VMCOREINFO_BYTES \
 310                                    + VMCOREINFO_NOTE_NAME_BYTES)
 311
 312/* Location of a reserved region to hold the crash kernel.
 313 */
 314extern struct resource crashk_res;
 315extern struct resource crashk_low_res;
 316typedef u32 note_buf_t[KEXEC_NOTE_BYTES/4];
 317extern note_buf_t __percpu *crash_notes;
 318extern u32 vmcoreinfo_note[VMCOREINFO_NOTE_SIZE/4];
 319extern size_t vmcoreinfo_size;
 320extern size_t vmcoreinfo_max_size;
 321
 322/* flag to track if kexec reboot is in progress */
 323extern bool kexec_in_progress;
 324
 325int __init parse_crashkernel(char *cmdline, unsigned long long system_ram,
 326                unsigned long long *crash_size, unsigned long long *crash_base);
 327int parse_crashkernel_high(char *cmdline, unsigned long long system_ram,
 328                unsigned long long *crash_size, unsigned long long *crash_base);
 329int parse_crashkernel_low(char *cmdline, unsigned long long system_ram,
 330                unsigned long long *crash_size, unsigned long long *crash_base);
 331int crash_shrink_memory(unsigned long new_size);
 332size_t crash_get_memory_size(void);
 333void crash_free_reserved_phys_range(unsigned long begin, unsigned long end);
 334
 335int __weak arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
 336                                         unsigned long buf_len);
 337void * __weak arch_kexec_kernel_image_load(struct kimage *image);
 338int __weak arch_kimage_file_post_load_cleanup(struct kimage *image);
 339int __weak arch_kexec_kernel_verify_sig(struct kimage *image, void *buf,
 340                                        unsigned long buf_len);
 341int __weak arch_kexec_apply_relocations_add(const Elf_Ehdr *ehdr,
 342                                        Elf_Shdr *sechdrs, unsigned int relsec);
 343int __weak arch_kexec_apply_relocations(const Elf_Ehdr *ehdr, Elf_Shdr *sechdrs,
 344                                        unsigned int relsec);
 345void arch_kexec_protect_crashkres(void);
 346void arch_kexec_unprotect_crashkres(void);
 347
 348#ifndef page_to_boot_pfn
 349static inline unsigned long page_to_boot_pfn(struct page *page)
 350{
 351        return page_to_pfn(page);
 352}
 353#endif
 354
 355#ifndef boot_pfn_to_page
 356static inline struct page *boot_pfn_to_page(unsigned long boot_pfn)
 357{
 358        return pfn_to_page(boot_pfn);
 359}
 360#endif
 361
 362#ifndef phys_to_boot_phys
 363static inline unsigned long phys_to_boot_phys(phys_addr_t phys)
 364{
 365        return phys;
 366}
 367#endif
 368
 369#ifndef boot_phys_to_phys
 370static inline phys_addr_t boot_phys_to_phys(unsigned long boot_phys)
 371{
 372        return boot_phys;
 373}
 374#endif
 375
 376static inline unsigned long virt_to_boot_phys(void *addr)
 377{
 378        return phys_to_boot_phys(__pa((unsigned long)addr));
 379}
 380
 381static inline void *boot_phys_to_virt(unsigned long entry)
 382{
 383        return phys_to_virt(boot_phys_to_phys(entry));
 384}
 385
 386#else /* !CONFIG_KEXEC_CORE */
 387struct pt_regs;
 388struct task_struct;
 389static inline void __crash_kexec(struct pt_regs *regs) { }
 390static inline void crash_kexec(struct pt_regs *regs) { }
 391static inline int kexec_should_crash(struct task_struct *p) { return 0; }
 392static inline int kexec_crash_loaded(void) { return 0; }
 393#define kexec_in_progress false
 394#endif /* CONFIG_KEXEC_CORE */
 395
 396#endif /* !defined(__ASSEBMLY__) */
 397
 398#endif /* LINUX_KEXEC_H */
 399