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1: #ifndef _LINUX_INIT_H 2: #define _LINUX_INIT_H 3: 4: #include <linux/compiler.h> 5: #include <linux/types.h> 6: 7: /* These macros are used to mark some functions or 8: * initialized data (doesn't apply to uninitialized data) 9: * as `initialization' functions. The kernel can take this 10: * as hint that the function is used only during the initialization 11: * phase and free up used memory resources after 12: * 13: * Usage: 14: * For functions: 15: * 16: * You should add __init immediately before the function name, like: 17: * 18: * static void __init initme(int x, int y) 19: * { 20: * extern int z; z = x * y; 21: * } 22: * 23: * If the function has a prototype somewhere, you can also add 24: * __init between closing brace of the prototype and semicolon: 25: * 26: * extern int initialize_foobar_device(int, int, int) __init; 27: * 28: * For initialized data: 29: * You should insert __initdata or __initconst between the variable name 30: * and equal sign followed by value, e.g.: 31: * 32: * static int init_variable __initdata = 0; 33: * static const char linux_logo[] __initconst = { 0x32, 0x36, ... }; 34: * 35: * Don't forget to initialize data not at file scope, i.e. within a function, 36: * as gcc otherwise puts the data into the bss section and not into the init 37: * section. 38: */ 39: 40: /* These are for everybody (although not all archs will actually 41: discard it in modules) */ 42: #define __init __section(.init.text) __cold notrace 43: #define __initdata __section(.init.data) 44: #define __initconst __constsection(.init.rodata) 45: #define __exitdata __section(.exit.data) 46: #define __exit_call __used __section(.exitcall.exit) 47: 48: /* 49: * Some architecture have tool chains which do not handle rodata attributes 50: * correctly. For those disable special sections for const, so that other 51: * architectures can annotate correctly. 52: */ 53: #ifdef CONFIG_BROKEN_RODATA 54: #define __constsection(x) 55: #else 56: #define __constsection(x) __section(x) 57: #endif 58: 59: /* 60: * modpost check for section mismatches during the kernel build. 61: * A section mismatch happens when there are references from a 62: * code or data section to an init section (both code or data). 63: * The init sections are (for most archs) discarded by the kernel 64: * when early init has completed so all such references are potential bugs. 65: * For exit sections the same issue exists. 66: * 67: * The following markers are used for the cases where the reference to 68: * the *init / *exit section (code or data) is valid and will teach 69: * modpost not to issue a warning. Intended semantics is that a code or 70: * data tagged __ref* can reference code or data from init section without 71: * producing a warning (of course, no warning does not mean code is 72: * correct, so optimally document why the __ref is needed and why it's OK). 73: * 74: * The markers follow same syntax rules as __init / __initdata. 75: */ 76: #define __ref __section(.ref.text) noinline 77: #define __refdata __section(.ref.data) 78: #define __refconst __constsection(.ref.rodata) 79: 80: /* compatibility defines */ 81: #define __init_refok __ref 82: #define __initdata_refok __refdata 83: #define __exit_refok __ref 84: 85: 86: #ifdef MODULE 87: #define __exitused 88: #else 89: #define __exitused __used 90: #endif 91: 92: #define __exit __section(.exit.text) __exitused __cold notrace 93: 94: /* temporary, until all users are removed */ 95: #define __cpuinit 96: #define __cpuinitdata 97: #define __cpuinitconst 98: #define __cpuexit 99: #define __cpuexitdata 100: #define __cpuexitconst 101: 102: /* Used for MEMORY_HOTPLUG */ 103: #define __meminit __section(.meminit.text) __cold notrace 104: #define __meminitdata __section(.meminit.data) 105: #define __meminitconst __constsection(.meminit.rodata) 106: #define __memexit __section(.memexit.text) __exitused __cold notrace 107: #define __memexitdata __section(.memexit.data) 108: #define __memexitconst __constsection(.memexit.rodata) 109: 110: /* For assembly routines */ 111: #define __HEAD .section ".head.text","ax" 112: #define __INIT .section ".init.text","ax" 113: #define __FINIT .previous 114: 115: #define __INITDATA .section ".init.data","aw",%progbits 116: #define __INITRODATA .section ".init.rodata","a",%progbits 117: #define __FINITDATA .previous 118: 119: /* temporary, until all users are removed */ 120: #define __CPUINIT 121: 122: #define __MEMINIT .section ".meminit.text", "ax" 123: #define __MEMINITDATA .section ".meminit.data", "aw" 124: #define __MEMINITRODATA .section ".meminit.rodata", "a" 125: 126: /* silence warnings when references are OK */ 127: #define __REF .section ".ref.text", "ax" 128: #define __REFDATA .section ".ref.data", "aw" 129: #define __REFCONST .section ".ref.rodata", "a" 130: 131: #ifndef __ASSEMBLY__ 132: /* 133: * Used for initialization calls.. 134: */ 135: typedef int (*initcall_t)(void); 136: typedef void (*exitcall_t)(void); 137: 138: extern initcall_t __con_initcall_start[], __con_initcall_end[]; 139: extern initcall_t __security_initcall_start[], __security_initcall_end[]; 140: 141: /* Used for contructor calls. */ 142: typedef void (*ctor_fn_t)(void); 143: 144: /* Defined in init/main.c */ 145: extern int do_one_initcall(initcall_t fn); 146: extern char __initdata boot_command_line[]; 147: extern char *saved_command_line; 148: extern unsigned int reset_devices; 149: 150: /* used by init/main.c */ 151: void setup_arch(char **); 152: void prepare_namespace(void); 153: void __init load_default_modules(void); 154: int __init init_rootfs(void); 155: 156: extern void (*late_time_init)(void); 157: 158: extern bool initcall_debug; 159: 160: #endif 161: 162: #ifndef MODULE 163: 164: #ifndef __ASSEMBLY__ 165: 166: /* initcalls are now grouped by functionality into separate 167: * subsections. Ordering inside the subsections is determined 168: * by link order. 169: * For backwards compatibility, initcall() puts the call in 170: * the device init subsection. 171: * 172: * The `id' arg to __define_initcall() is needed so that multiple initcalls 173: * can point at the same handler without causing duplicate-symbol build errors. 174: */ 175: 176: #define __define_initcall(fn, id) \ 177: static initcall_t __initcall_##fn##id __used \ 178: __attribute__((__section__(".initcall" #id ".init"))) = fn 179: 180: /* 181: * Early initcalls run before initializing SMP. 182: * 183: * Only for built-in code, not modules. 184: */ 185: #define early_initcall(fn) __define_initcall(fn, early) 186: 187: /* 188: * A "pure" initcall has no dependencies on anything else, and purely 189: * initializes variables that couldn't be statically initialized. 190: * 191: * This only exists for built-in code, not for modules. 192: * Keep main.c:initcall_level_names[] in sync. 193: */ 194: #define pure_initcall(fn) __define_initcall(fn, 0) 195: 196: #define core_initcall(fn) __define_initcall(fn, 1) 197: #define core_initcall_sync(fn) __define_initcall(fn, 1s) 198: #define postcore_initcall(fn) __define_initcall(fn, 2) 199: #define postcore_initcall_sync(fn) __define_initcall(fn, 2s) 200: #define arch_initcall(fn) __define_initcall(fn, 3) 201: #define arch_initcall_sync(fn) __define_initcall(fn, 3s) 202: #define subsys_initcall(fn) __define_initcall(fn, 4) 203: #define subsys_initcall_sync(fn) __define_initcall(fn, 4s) 204: #define fs_initcall(fn) __define_initcall(fn, 5) 205: #define fs_initcall_sync(fn) __define_initcall(fn, 5s) 206: #define rootfs_initcall(fn) __define_initcall(fn, rootfs) 207: #define device_initcall(fn) __define_initcall(fn, 6) 208: #define device_initcall_sync(fn) __define_initcall(fn, 6s) 209: #define late_initcall(fn) __define_initcall(fn, 7) 210: #define late_initcall_sync(fn) __define_initcall(fn, 7s) 211: 212: #define __initcall(fn) device_initcall(fn) 213: 214: #define __exitcall(fn) \ 215: static exitcall_t __exitcall_##fn __exit_call = fn 216: 217: #define console_initcall(fn) \ 218: static initcall_t __initcall_##fn \ 219: __used __section(.con_initcall.init) = fn 220: 221: #define security_initcall(fn) \ 222: static initcall_t __initcall_##fn \ 223: __used __section(.security_initcall.init) = fn 224: 225: struct obs_kernel_param { 226: const char *str; 227: int (*setup_func)(char *); 228: int early; 229: }; 230: 231: /* 232: * Only for really core code. See moduleparam.h for the normal way. 233: * 234: * Force the alignment so the compiler doesn't space elements of the 235: * obs_kernel_param "array" too far apart in .init.setup. 236: */ 237: #define __setup_param(str, unique_id, fn, early) \ 238: static const char __setup_str_##unique_id[] __initconst \ 239: __aligned(1) = str; \ 240: static struct obs_kernel_param __setup_##unique_id \ 241: __used __section(.init.setup) \ 242: __attribute__((aligned((sizeof(long))))) \ 243: = { __setup_str_##unique_id, fn, early } 244: 245: #define __setup(str, fn) \ 246: __setup_param(str, fn, fn, 0) 247: 248: /* NOTE: fn is as per module_param, not __setup! Emits warning if fn 249: * returns non-zero. */ 250: #define early_param(str, fn) \ 251: __setup_param(str, fn, fn, 1) 252: 253: /* Relies on boot_command_line being set */ 254: void __init parse_early_param(void); 255: void __init parse_early_options(char *cmdline); 256: #endif /* __ASSEMBLY__ */ 257: 258: /** 259: * module_init() - driver initialization entry point 260: * @x: function to be run at kernel boot time or module insertion 261: * 262: * module_init() will either be called during do_initcalls() (if 263: * builtin) or at module insertion time (if a module). There can only 264: * be one per module. 265: */ 266: #define module_init(x) __initcall(x); 267: 268: /** 269: * module_exit() - driver exit entry point 270: * @x: function to be run when driver is removed 271: * 272: * module_exit() will wrap the driver clean-up code 273: * with cleanup_module() when used with rmmod when 274: * the driver is a module. If the driver is statically 275: * compiled into the kernel, module_exit() has no effect. 276: * There can only be one per module. 277: */ 278: #define module_exit(x) __exitcall(x); 279: 280: #else /* MODULE */ 281: 282: /* Don't use these in loadable modules, but some people do... */ 283: #define early_initcall(fn) module_init(fn) 284: #define core_initcall(fn) module_init(fn) 285: #define postcore_initcall(fn) module_init(fn) 286: #define arch_initcall(fn) module_init(fn) 287: #define subsys_initcall(fn) module_init(fn) 288: #define fs_initcall(fn) module_init(fn) 289: #define device_initcall(fn) module_init(fn) 290: #define late_initcall(fn) module_init(fn) 291: 292: #define security_initcall(fn) module_init(fn) 293: 294: /* Each module must use one module_init(). */ 295: #define module_init(initfn) \ 296: static inline initcall_t __inittest(void) \ 297: { return initfn; } \ 298: int init_module(void) __attribute__((alias(#initfn))); 299: 300: /* This is only required if you want to be unloadable. */ 301: #define module_exit(exitfn) \ 302: static inline exitcall_t __exittest(void) \ 303: { return exitfn; } \ 304: void cleanup_module(void) __attribute__((alias(#exitfn))); 305: 306: #define __setup_param(str, unique_id, fn) /* nothing */ 307: #define __setup(str, func) /* nothing */ 308: #endif 309: 310: /* Data marked not to be saved by software suspend */ 311: #define __nosavedata __section(.data..nosave) 312: 313: /* This means "can be init if no module support, otherwise module load 314: may call it." */ 315: #ifdef CONFIG_MODULES 316: #define __init_or_module 317: #define __initdata_or_module 318: #define __initconst_or_module 319: #define __INIT_OR_MODULE .text 320: #define __INITDATA_OR_MODULE .data 321: #define __INITRODATA_OR_MODULE .section ".rodata","a",%progbits 322: #else 323: #define __init_or_module __init 324: #define __initdata_or_module __initdata 325: #define __initconst_or_module __initconst 326: #define __INIT_OR_MODULE __INIT 327: #define __INITDATA_OR_MODULE __INITDATA 328: #define __INITRODATA_OR_MODULE __INITRODATA 329: #endif /*CONFIG_MODULES*/ 330: 331: #ifdef MODULE 332: #define __exit_p(x) x 333: #else 334: #define __exit_p(x) NULL 335: #endif 336: 337: #endif /* _LINUX_INIT_H */ 338: