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 <uapi/linux/kexec.h>
  18
  19#ifdef CONFIG_KEXEC_CORE
  20#include <linux/list.h>
  21#include <linux/linkage.h>
  22#include <linux/compat.h>
  23#include <linux/ioport.h>
  24#include <linux/elfcore.h>
  25#include <linux/elf.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
  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_NOTE_HEAD_BYTES ALIGN(sizeof(struct elf_note), 4)
  64#define KEXEC_CORE_NOTE_NAME "CORE"
  65#define KEXEC_CORE_NOTE_NAME_BYTES ALIGN(sizeof(KEXEC_CORE_NOTE_NAME), 4)
  66#define KEXEC_CORE_NOTE_DESC_BYTES ALIGN(sizeof(struct elf_prstatus), 4)
  67/*
  68 * The per-cpu notes area is a list of notes terminated by a "NULL"
  69 * note header.  For kdump, the code in vmcore.c runs in the context
  70 * of the second kernel to combine them into one note.
  71 */
  72#ifndef KEXEC_NOTE_BYTES
  73#define KEXEC_NOTE_BYTES ( (KEXEC_NOTE_HEAD_BYTES * 2) +                \
  74                            KEXEC_CORE_NOTE_NAME_BYTES +                \
  75                            KEXEC_CORE_NOTE_DESC_BYTES )
  76#endif
  77
  78/*
  79 * This structure is used to hold the arguments that are used when loading
  80 * kernel binaries.
  81 */
  82
  83typedef unsigned long kimage_entry_t;
  84
  85struct kexec_segment {
  86        /*
  87         * This pointer can point to user memory if kexec_load() system
  88         * call is used or will point to kernel memory if
  89         * kexec_file_load() system call is used.
  90         *
  91         * Use ->buf when expecting to deal with user memory and use ->kbuf
  92         * when expecting to deal with kernel memory.
  93         */
  94        union {
  95                void __user *buf;
  96                void *kbuf;
  97        };
  98        size_t bufsz;
  99        unsigned long mem;
 100        size_t memsz;
 101};
 102
 103#ifdef CONFIG_COMPAT
 104struct compat_kexec_segment {
 105        compat_uptr_t buf;
 106        compat_size_t bufsz;
 107        compat_ulong_t mem;     /* User space sees this as a (void *) ... */
 108        compat_size_t memsz;
 109};
 110#endif
 111
 112#ifdef CONFIG_KEXEC_FILE
 113struct purgatory_info {
 114        /* Pointer to elf header of read only purgatory */
 115        Elf_Ehdr *ehdr;
 116
 117        /* Pointer to purgatory sechdrs which are modifiable */
 118        Elf_Shdr *sechdrs;
 119        /*
 120         * Temporary buffer location where purgatory is loaded and relocated
 121         * This memory can be freed post image load
 122         */
 123        void *purgatory_buf;
 124
 125        /* Address where purgatory is finally loaded and is executed from */
 126        unsigned long purgatory_load_addr;
 127};
 128
 129typedef int (kexec_probe_t)(const char *kernel_buf, unsigned long kernel_size);
 130typedef void *(kexec_load_t)(struct kimage *image, char *kernel_buf,
 131                             unsigned long kernel_len, char *initrd,
 132                             unsigned long initrd_len, char *cmdline,
 133                             unsigned long cmdline_len);
 134typedef int (kexec_cleanup_t)(void *loader_data);
 135
 136#ifdef CONFIG_KEXEC_VERIFY_SIG
 137typedef int (kexec_verify_sig_t)(const char *kernel_buf,
 138                                 unsigned long kernel_len);
 139#endif
 140
 141struct kexec_file_ops {
 142        kexec_probe_t *probe;
 143        kexec_load_t *load;
 144        kexec_cleanup_t *cleanup;
 145#ifdef CONFIG_KEXEC_VERIFY_SIG
 146        kexec_verify_sig_t *verify_sig;
 147#endif
 148};
 149#endif
 150
 151struct kimage {
 152        kimage_entry_t head;
 153        kimage_entry_t *entry;
 154        kimage_entry_t *last_entry;
 155
 156        unsigned long start;
 157        struct page *control_code_page;
 158        struct page *swap_page;
 159
 160        unsigned long nr_segments;
 161        struct kexec_segment segment[KEXEC_SEGMENT_MAX];
 162
 163        struct list_head control_pages;
 164        struct list_head dest_pages;
 165        struct list_head unusable_pages;
 166
 167        /* Address of next control page to allocate for crash kernels. */
 168        unsigned long control_page;
 169
 170        /* Flags to indicate special processing */
 171        unsigned int type : 1;
 172#define KEXEC_TYPE_DEFAULT 0
 173#define KEXEC_TYPE_CRASH   1
 174        unsigned int preserve_context : 1;
 175        /* If set, we are using file mode kexec syscall */
 176        unsigned int file_mode:1;
 177
 178#ifdef ARCH_HAS_KIMAGE_ARCH
 179        struct kimage_arch arch;
 180#endif
 181
 182#ifdef CONFIG_KEXEC_FILE
 183        /* Additional fields for file based kexec syscall */
 184        void *kernel_buf;
 185        unsigned long kernel_buf_len;
 186
 187        void *initrd_buf;
 188        unsigned long initrd_buf_len;
 189
 190        char *cmdline_buf;
 191        unsigned long cmdline_buf_len;
 192
 193        /* File operations provided by image loader */
 194        struct kexec_file_ops *fops;
 195
 196        /* Image loader handling the kernel can store a pointer here */
 197        void *image_loader_data;
 198
 199        /* Information for loading purgatory */
 200        struct purgatory_info purgatory_info;
 201#endif
 202};
 203
 204/* kexec interface functions */
 205extern void machine_kexec(struct kimage *image);
 206extern int machine_kexec_prepare(struct kimage *image);
 207extern void machine_kexec_cleanup(struct kimage *image);
 208extern asmlinkage long sys_kexec_load(unsigned long entry,
 209                                        unsigned long nr_segments,
 210                                        struct kexec_segment __user *segments,
 211                                        unsigned long flags);
 212extern int kernel_kexec(void);
 213extern int kexec_add_buffer(struct kimage *image, char *buffer,
 214                            unsigned long bufsz, unsigned long memsz,
 215                            unsigned long buf_align, unsigned long buf_min,
 216                            unsigned long buf_max, bool top_down,
 217                            unsigned long *load_addr);
 218extern struct page *kimage_alloc_control_pages(struct kimage *image,
 219                                                unsigned int order);
 220extern int kexec_load_purgatory(struct kimage *image, unsigned long min,
 221                                unsigned long max, int top_down,
 222                                unsigned long *load_addr);
 223extern int kexec_purgatory_get_set_symbol(struct kimage *image,
 224                                          const char *name, void *buf,
 225                                          unsigned int size, bool get_value);
 226extern void *kexec_purgatory_get_symbol_addr(struct kimage *image,
 227                                             const char *name);
 228extern void __crash_kexec(struct pt_regs *);
 229extern void crash_kexec(struct pt_regs *);
 230int kexec_should_crash(struct task_struct *);
 231void crash_save_cpu(struct pt_regs *regs, int cpu);
 232void crash_save_vmcoreinfo(void);
 233void crash_map_reserved_pages(void);
 234void crash_unmap_reserved_pages(void);
 235void arch_crash_save_vmcoreinfo(void);
 236__printf(1, 2)
 237void vmcoreinfo_append_str(const char *fmt, ...);
 238unsigned long paddr_vmcoreinfo_note(void);
 239
 240#define VMCOREINFO_OSRELEASE(value) \
 241        vmcoreinfo_append_str("OSRELEASE=%s\n", value)
 242#define VMCOREINFO_PAGESIZE(value) \
 243        vmcoreinfo_append_str("PAGESIZE=%ld\n", value)
 244#define VMCOREINFO_SYMBOL(name) \
 245        vmcoreinfo_append_str("SYMBOL(%s)=%lx\n", #name, (unsigned long)&name)
 246#define VMCOREINFO_SIZE(name) \
 247        vmcoreinfo_append_str("SIZE(%s)=%lu\n", #name, \
 248                              (unsigned long)sizeof(name))
 249#define VMCOREINFO_STRUCT_SIZE(name) \
 250        vmcoreinfo_append_str("SIZE(%s)=%lu\n", #name, \
 251                              (unsigned long)sizeof(struct name))
 252#define VMCOREINFO_OFFSET(name, field) \
 253        vmcoreinfo_append_str("OFFSET(%s.%s)=%lu\n", #name, #field, \
 254                              (unsigned long)offsetof(struct name, field))
 255#define VMCOREINFO_LENGTH(name, value) \
 256        vmcoreinfo_append_str("LENGTH(%s)=%lu\n", #name, (unsigned long)value)
 257#define VMCOREINFO_NUMBER(name) \
 258        vmcoreinfo_append_str("NUMBER(%s)=%ld\n", #name, (long)name)
 259#define VMCOREINFO_CONFIG(name) \
 260        vmcoreinfo_append_str("CONFIG_%s=y\n", #name)
 261
 262extern struct kimage *kexec_image;
 263extern struct kimage *kexec_crash_image;
 264extern int kexec_load_disabled;
 265
 266#ifndef kexec_flush_icache_page
 267#define kexec_flush_icache_page(page)
 268#endif
 269
 270/* List of defined/legal kexec flags */
 271#ifndef CONFIG_KEXEC_JUMP
 272#define KEXEC_FLAGS    KEXEC_ON_CRASH
 273#else
 274#define KEXEC_FLAGS    (KEXEC_ON_CRASH | KEXEC_PRESERVE_CONTEXT)
 275#endif
 276
 277/* List of defined/legal kexec file flags */
 278#define KEXEC_FILE_FLAGS        (KEXEC_FILE_UNLOAD | KEXEC_FILE_ON_CRASH | \
 279                                 KEXEC_FILE_NO_INITRAMFS)
 280
 281#define VMCOREINFO_BYTES           (4096)
 282#define VMCOREINFO_NOTE_NAME       "VMCOREINFO"
 283#define VMCOREINFO_NOTE_NAME_BYTES ALIGN(sizeof(VMCOREINFO_NOTE_NAME), 4)
 284#define VMCOREINFO_NOTE_SIZE       (KEXEC_NOTE_HEAD_BYTES*2 + VMCOREINFO_BYTES \
 285                                    + VMCOREINFO_NOTE_NAME_BYTES)
 286
 287/* Location of a reserved region to hold the crash kernel.
 288 */
 289extern struct resource crashk_res;
 290extern struct resource crashk_low_res;
 291typedef u32 note_buf_t[KEXEC_NOTE_BYTES/4];
 292extern note_buf_t __percpu *crash_notes;
 293extern u32 vmcoreinfo_note[VMCOREINFO_NOTE_SIZE/4];
 294extern size_t vmcoreinfo_size;
 295extern size_t vmcoreinfo_max_size;
 296
 297/* flag to track if kexec reboot is in progress */
 298extern bool kexec_in_progress;
 299
 300int __init parse_crashkernel(char *cmdline, unsigned long long system_ram,
 301                unsigned long long *crash_size, unsigned long long *crash_base);
 302int parse_crashkernel_high(char *cmdline, unsigned long long system_ram,
 303                unsigned long long *crash_size, unsigned long long *crash_base);
 304int parse_crashkernel_low(char *cmdline, unsigned long long system_ram,
 305                unsigned long long *crash_size, unsigned long long *crash_base);
 306int crash_shrink_memory(unsigned long new_size);
 307size_t crash_get_memory_size(void);
 308void crash_free_reserved_phys_range(unsigned long begin, unsigned long end);
 309
 310int __weak arch_kexec_kernel_image_probe(struct kimage *image, void *buf,
 311                                         unsigned long buf_len);
 312void * __weak arch_kexec_kernel_image_load(struct kimage *image);
 313int __weak arch_kimage_file_post_load_cleanup(struct kimage *image);
 314int __weak arch_kexec_kernel_verify_sig(struct kimage *image, void *buf,
 315                                        unsigned long buf_len);
 316int __weak arch_kexec_apply_relocations_add(const Elf_Ehdr *ehdr,
 317                                        Elf_Shdr *sechdrs, unsigned int relsec);
 318int __weak arch_kexec_apply_relocations(const Elf_Ehdr *ehdr, Elf_Shdr *sechdrs,
 319                                        unsigned int relsec);
 320
 321#else /* !CONFIG_KEXEC_CORE */
 322struct pt_regs;
 323struct task_struct;
 324static inline void __crash_kexec(struct pt_regs *regs) { }
 325static inline void crash_kexec(struct pt_regs *regs) { }
 326static inline int kexec_should_crash(struct task_struct *p) { return 0; }
 327#define kexec_in_progress false
 328#endif /* CONFIG_KEXEC_CORE */
 329
 330#endif /* !defined(__ASSEBMLY__) */
 331
 332#endif /* LINUX_KEXEC_H */
 333