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
  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
 112struct kexec_sha_region {
 113        unsigned long start;
 114        unsigned long len;
 115};
 116
 117struct purgatory_info {
 118        /* Pointer to elf header of read only purgatory */
 119        Elf_Ehdr *ehdr;
 120
 121        /* Pointer to purgatory sechdrs which are modifiable */
 122        Elf_Shdr *sechdrs;
 123        /*
 124         * Temporary buffer location where purgatory is loaded and relocated
 125         * This memory can be freed post image load
 126         */
 127        void *purgatory_buf;
 128
 129        /* Address where purgatory is finally loaded and is executed from */
 130        unsigned long purgatory_load_addr;
 131};
 132
 133struct kimage {
 134        kimage_entry_t head;
 135        kimage_entry_t *entry;
 136        kimage_entry_t *last_entry;
 137
 138        unsigned long start;
 139        struct page *control_code_page;
 140        struct page *swap_page;
 141
 142        unsigned long nr_segments;
 143        struct kexec_segment segment[KEXEC_SEGMENT_MAX];
 144
 145        struct list_head control_pages;
 146        struct list_head dest_pages;
 147        struct list_head unusable_pages;
 148
 149        /* Address of next control page to allocate for crash kernels. */
 150        unsigned long control_page;
 151
 152        /* Flags to indicate special processing */
 153        unsigned int type : 1;
 154#define KEXEC_TYPE_DEFAULT 0
 155#define KEXEC_TYPE_CRASH   1
 156        unsigned int preserve_context : 1;
 157        /* If set, we are using file mode kexec syscall */
 158        unsigned int file_mode:1;
 159
 160#ifdef ARCH_HAS_KIMAGE_ARCH
 161        struct kimage_arch arch;
 162#endif
 163
 164        /* Additional fields for file based kexec syscall */
 165        void *kernel_buf;
 166        unsigned long kernel_buf_len;
 167
 168        void *initrd_buf;
 169        unsigned long initrd_buf_len;
 170
 171        char *cmdline_buf;
 172        unsigned long cmdline_buf_len;
 173
 174        /* File operations provided by image loader */
 175        struct kexec_file_ops *fops;
 176
 177        /* Image loader handling the kernel can store a pointer here */
 178        void *image_loader_data;
 179
 180        /* Information for loading purgatory */
 181        struct purgatory_info purgatory_info;
 182};
 183
 184/*
 185 * Keeps track of buffer parameters as provided by caller for requesting
 186 * memory placement of buffer.
 187 */
 188struct kexec_buf {
 189        struct kimage *image;
 190        char *buffer;
 191        unsigned long bufsz;
 192        unsigned long mem;
 193        unsigned long memsz;
 194        unsigned long buf_align;
 195        unsigned long buf_min;
 196        unsigned long buf_max;
 197        bool top_down;          /* allocate from top of memory hole */
 198};
 199
 200typedef int (kexec_probe_t)(const char *kernel_buf, unsigned long kernel_size);
 201typedef void *(kexec_load_t)(struct kimage *image, char *kernel_buf,
 202                             unsigned long kernel_len, char *initrd,
 203                             unsigned long initrd_len, char *cmdline,
 204                             unsigned long cmdline_len);
 205typedef int (kexec_cleanup_t)(void *loader_data);
 206typedef int (kexec_verify_sig_t)(const char *kernel_buf,
 207                                 unsigned long kernel_len);
 208
 209struct kexec_file_ops {
 210        kexec_probe_t *probe;
 211        kexec_load_t *load;
 212        kexec_cleanup_t *cleanup;
 213        kexec_verify_sig_t *verify_sig;
 214};
 215
 216/* kexec interface functions */
 217extern void machine_kexec(struct kimage *image);
 218extern int machine_kexec_prepare(struct kimage *image);
 219extern void machine_kexec_cleanup(struct kimage *image);
 220extern asmlinkage long sys_kexec_load(unsigned long entry,
 221                                        unsigned long nr_segments,
 222                                        struct kexec_segment __user *segments,
 223                                        unsigned long flags);
 224extern int kernel_kexec(void);
 225extern int kexec_add_buffer(struct kimage *image, char *buffer,
 226                            unsigned long bufsz, unsigned long memsz,
 227                            unsigned long buf_align, unsigned long buf_min,
 228                            unsigned long buf_max, bool top_down,
 229                            unsigned long *load_addr);
 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 *);
 241int kexec_should_crash(struct task_struct *);
 242void crash_save_cpu(struct pt_regs *regs, int cpu);
 243void crash_save_vmcoreinfo(void);
 244void crash_map_reserved_pages(void);
 245void crash_unmap_reserved_pages(void);
 246void arch_crash_save_vmcoreinfo(void);
 247__printf(1, 2)
 248void vmcoreinfo_append_str(const char *fmt, ...);
 249unsigned long paddr_vmcoreinfo_note(void);
 250
 251#define VMCOREINFO_OSRELEASE(value) \
 252        vmcoreinfo_append_str("OSRELEASE=%s\n", value)
 253#define VMCOREINFO_PAGESIZE(value) \
 254        vmcoreinfo_append_str("PAGESIZE=%ld\n", value)
 255#define VMCOREINFO_SYMBOL(name) \
 256        vmcoreinfo_append_str("SYMBOL(%s)=%lx\n", #name, (unsigned long)&name)
 257#define VMCOREINFO_SIZE(name) \
 258        vmcoreinfo_append_str("SIZE(%s)=%lu\n", #name, \
 259                              (unsigned long)sizeof(name))
 260#define VMCOREINFO_STRUCT_SIZE(name) \
 261        vmcoreinfo_append_str("SIZE(%s)=%lu\n", #name, \
 262                              (unsigned long)sizeof(struct name))
 263#define VMCOREINFO_OFFSET(name, field) \
 264        vmcoreinfo_append_str("OFFSET(%s.%s)=%lu\n", #name, #field, \
 265                              (unsigned long)offsetof(struct name, field))
 266#define VMCOREINFO_LENGTH(name, value) \
 267        vmcoreinfo_append_str("LENGTH(%s)=%lu\n", #name, (unsigned long)value)
 268#define VMCOREINFO_NUMBER(name) \
 269        vmcoreinfo_append_str("NUMBER(%s)=%ld\n", #name, (long)name)
 270#define VMCOREINFO_CONFIG(name) \
 271        vmcoreinfo_append_str("CONFIG_%s=y\n", #name)
 272
 273extern struct kimage *kexec_image;
 274extern struct kimage *kexec_crash_image;
 275extern int kexec_load_disabled;
 276
 277#ifndef kexec_flush_icache_page
 278#define kexec_flush_icache_page(page)
 279#endif
 280
 281/* List of defined/legal kexec flags */
 282#ifndef CONFIG_KEXEC_JUMP
 283#define KEXEC_FLAGS    KEXEC_ON_CRASH
 284#else
 285#define KEXEC_FLAGS    (KEXEC_ON_CRASH | KEXEC_PRESERVE_CONTEXT)
 286#endif
 287
 288/* List of defined/legal kexec file flags */
 289#define KEXEC_FILE_FLAGS        (KEXEC_FILE_UNLOAD | KEXEC_FILE_ON_CRASH | \
 290                                 KEXEC_FILE_NO_INITRAMFS)
 291
 292#define VMCOREINFO_BYTES           (4096)
 293#define VMCOREINFO_NOTE_NAME       "VMCOREINFO"
 294#define VMCOREINFO_NOTE_NAME_BYTES ALIGN(sizeof(VMCOREINFO_NOTE_NAME), 4)
 295#define VMCOREINFO_NOTE_SIZE       (KEXEC_NOTE_HEAD_BYTES*2 + VMCOREINFO_BYTES \
 296                                    + VMCOREINFO_NOTE_NAME_BYTES)
 297
 298/* Location of a reserved region to hold the crash kernel.
 299 */
 300extern struct resource crashk_res;
 301extern struct resource crashk_low_res;
 302typedef u32 note_buf_t[KEXEC_NOTE_BYTES/4];
 303extern note_buf_t __percpu *crash_notes;
 304extern u32 vmcoreinfo_note[VMCOREINFO_NOTE_SIZE/4];
 305extern size_t vmcoreinfo_size;
 306extern size_t vmcoreinfo_max_size;
 307
 308/* flag to track if kexec reboot is in progress */
 309extern bool kexec_in_progress;
 310
 311int __init parse_crashkernel(char *cmdline, unsigned long long system_ram,
 312                unsigned long long *crash_size, unsigned long long *crash_base);
 313int parse_crashkernel_high(char *cmdline, unsigned long long system_ram,
 314                unsigned long long *crash_size, unsigned long long *crash_base);
 315int parse_crashkernel_low(char *cmdline, unsigned long long system_ram,
 316                unsigned long long *crash_size, unsigned long long *crash_base);
 317int crash_shrink_memory(unsigned long new_size);
 318size_t crash_get_memory_size(void);
 319void crash_free_reserved_phys_range(unsigned long begin, unsigned long end);
 320
 321#else /* !CONFIG_KEXEC */
 322struct pt_regs;
 323struct task_struct;
 324static inline void crash_kexec(struct pt_regs *regs) { }
 325static inline int kexec_should_crash(struct task_struct *p) { return 0; }
 326#endif /* CONFIG_KEXEC */
 327
 328#endif /* !defined(__ASSEBMLY__) */
 329
 330#endif /* LINUX_KEXEC_H */
 331