Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | #ifndef _LINUX_INIT_H |
| 2 | #define _LINUX_INIT_H |
| 3 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 4 | #include <linux/compiler.h> |
| 5 | |
| 6 | /* These macros are used to mark some functions or |
| 7 | * initialized data (doesn't apply to uninitialized data) |
| 8 | * as `initialization' functions. The kernel can take this |
| 9 | * as hint that the function is used only during the initialization |
| 10 | * phase and free up used memory resources after |
| 11 | * |
| 12 | * Usage: |
| 13 | * For functions: |
| 14 | * |
| 15 | * You should add __init immediately before the function name, like: |
| 16 | * |
| 17 | * static void __init initme(int x, int y) |
| 18 | * { |
| 19 | * extern int z; z = x * y; |
| 20 | * } |
| 21 | * |
| 22 | * If the function has a prototype somewhere, you can also add |
| 23 | * __init between closing brace of the prototype and semicolon: |
| 24 | * |
| 25 | * extern int initialize_foobar_device(int, int, int) __init; |
| 26 | * |
| 27 | * For initialized data: |
| 28 | * You should insert __initdata between the variable name and equal |
| 29 | * sign followed by value, e.g.: |
| 30 | * |
| 31 | * static int init_variable __initdata = 0; |
| 32 | * static char linux_logo[] __initdata = { 0x32, 0x36, ... }; |
| 33 | * |
| 34 | * Don't forget to initialize data not at file scope, i.e. within a function, |
| 35 | * as gcc otherwise puts the data into the bss section and not into the init |
| 36 | * section. |
| 37 | * |
| 38 | * Also note, that this data cannot be "const". |
| 39 | */ |
| 40 | |
| 41 | /* These are for everybody (although not all archs will actually |
| 42 | discard it in modules) */ |
| 43 | #define __init __attribute__ ((__section__ (".init.text"))) |
| 44 | #define __initdata __attribute__ ((__section__ (".init.data"))) |
| 45 | #define __exitdata __attribute__ ((__section__(".exit.data"))) |
| 46 | #define __exit_call __attribute_used__ __attribute__ ((__section__ (".exitcall.exit"))) |
| 47 | |
Sam Ravnborg | 0e0d314 | 2007-05-17 20:14:48 +0200 | [diff] [blame] | 48 | /* modpost check for section mismatches during the kernel build. |
| 49 | * A section mismatch happens when there are references from a |
| 50 | * code or data section to an init section (both code or data). |
| 51 | * The init sections are (for most archs) discarded by the kernel |
| 52 | * when early init has completed so all such references are potential bugs. |
| 53 | * For exit sections the same issue exists. |
| 54 | * The following markers are used for the cases where the reference to |
| 55 | * the init/exit section (code or data) is valid and will teach modpost |
| 56 | * not to issue a warning. |
| 57 | * The markers follow same syntax rules as __init / __initdata. */ |
| 58 | #define __init_refok noinline __attribute__ ((__section__ (".text.init.refok"))) |
| 59 | #define __initdata_refok __attribute__ ((__section__ (".data.init.refok"))) |
| 60 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 61 | #ifdef MODULE |
| 62 | #define __exit __attribute__ ((__section__(".exit.text"))) |
| 63 | #else |
| 64 | #define __exit __attribute_used__ __attribute__ ((__section__(".exit.text"))) |
| 65 | #endif |
| 66 | |
| 67 | /* For assembly routines */ |
| 68 | #define __INIT .section ".init.text","ax" |
Prarit Bhargava | 86c0baf | 2007-05-02 19:27:05 +0200 | [diff] [blame] | 69 | #define __FINIT .previous |
Prarit Bhargava | 838c411 | 2007-05-15 01:41:43 -0700 | [diff] [blame] | 70 | #define __INITDATA .section ".init.data","aw" |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 71 | |
| 72 | #ifndef __ASSEMBLY__ |
| 73 | /* |
| 74 | * Used for initialization calls.. |
| 75 | */ |
| 76 | typedef int (*initcall_t)(void); |
| 77 | typedef void (*exitcall_t)(void); |
| 78 | |
| 79 | extern initcall_t __con_initcall_start[], __con_initcall_end[]; |
| 80 | extern initcall_t __security_initcall_start[], __security_initcall_end[]; |
| 81 | |
| 82 | /* Defined in init/main.c */ |
Alon Bar-Lev | 30d7e0d | 2007-02-12 00:53:52 -0800 | [diff] [blame] | 83 | extern char __initdata boot_command_line[]; |
| 84 | extern char *saved_command_line; |
Vivek Goyal | 7e96287 | 2006-09-27 01:50:44 -0700 | [diff] [blame] | 85 | extern unsigned int reset_devices; |
Adrian Bunk | 77d4758 | 2006-03-25 03:07:39 -0800 | [diff] [blame] | 86 | |
| 87 | /* used by init/main.c */ |
Adrian Bunk | 4659539 | 2007-05-08 00:24:47 -0700 | [diff] [blame] | 88 | void setup_arch(char **); |
| 89 | void prepare_namespace(void); |
Adrian Bunk | 77d4758 | 2006-03-25 03:07:39 -0800 | [diff] [blame] | 90 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 91 | #endif |
| 92 | |
| 93 | #ifndef MODULE |
| 94 | |
| 95 | #ifndef __ASSEMBLY__ |
| 96 | |
| 97 | /* initcalls are now grouped by functionality into separate |
| 98 | * subsections. Ordering inside the subsections is determined |
| 99 | * by link order. |
| 100 | * For backwards compatibility, initcall() puts the call in |
| 101 | * the device init subsection. |
Andrew Morton | 735a7ff | 2006-10-27 11:42:37 -0700 | [diff] [blame] | 102 | * |
| 103 | * The `id' arg to __define_initcall() is needed so that multiple initcalls |
| 104 | * can point at the same handler without causing duplicate-symbol build errors. |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 105 | */ |
| 106 | |
Andrew Morton | 735a7ff | 2006-10-27 11:42:37 -0700 | [diff] [blame] | 107 | #define __define_initcall(level,fn,id) \ |
| 108 | static initcall_t __initcall_##fn##id __attribute_used__ \ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 109 | __attribute__((__section__(".initcall" level ".init"))) = fn |
| 110 | |
Linus Torvalds | b3438f8 | 2006-11-20 11:47:18 -0800 | [diff] [blame] | 111 | /* |
| 112 | * A "pure" initcall has no dependencies on anything else, and purely |
| 113 | * initializes variables that couldn't be statically initialized. |
| 114 | * |
| 115 | * This only exists for built-in code, not for modules. |
| 116 | */ |
| 117 | #define pure_initcall(fn) __define_initcall("0",fn,1) |
| 118 | |
Andrew Morton | 735a7ff | 2006-10-27 11:42:37 -0700 | [diff] [blame] | 119 | #define core_initcall(fn) __define_initcall("1",fn,1) |
| 120 | #define core_initcall_sync(fn) __define_initcall("1s",fn,1s) |
| 121 | #define postcore_initcall(fn) __define_initcall("2",fn,2) |
| 122 | #define postcore_initcall_sync(fn) __define_initcall("2s",fn,2s) |
| 123 | #define arch_initcall(fn) __define_initcall("3",fn,3) |
| 124 | #define arch_initcall_sync(fn) __define_initcall("3s",fn,3s) |
| 125 | #define subsys_initcall(fn) __define_initcall("4",fn,4) |
| 126 | #define subsys_initcall_sync(fn) __define_initcall("4s",fn,4s) |
| 127 | #define fs_initcall(fn) __define_initcall("5",fn,5) |
| 128 | #define fs_initcall_sync(fn) __define_initcall("5s",fn,5s) |
Linus Torvalds | 8d610dd | 2006-12-11 12:12:04 -0800 | [diff] [blame] | 129 | #define rootfs_initcall(fn) __define_initcall("rootfs",fn,rootfs) |
Andrew Morton | 735a7ff | 2006-10-27 11:42:37 -0700 | [diff] [blame] | 130 | #define device_initcall(fn) __define_initcall("6",fn,6) |
| 131 | #define device_initcall_sync(fn) __define_initcall("6s",fn,6s) |
| 132 | #define late_initcall(fn) __define_initcall("7",fn,7) |
| 133 | #define late_initcall_sync(fn) __define_initcall("7s",fn,7s) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 134 | |
| 135 | #define __initcall(fn) device_initcall(fn) |
| 136 | |
| 137 | #define __exitcall(fn) \ |
| 138 | static exitcall_t __exitcall_##fn __exit_call = fn |
| 139 | |
| 140 | #define console_initcall(fn) \ |
| 141 | static initcall_t __initcall_##fn \ |
| 142 | __attribute_used__ __attribute__((__section__(".con_initcall.init")))=fn |
| 143 | |
| 144 | #define security_initcall(fn) \ |
| 145 | static initcall_t __initcall_##fn \ |
| 146 | __attribute_used__ __attribute__((__section__(".security_initcall.init"))) = fn |
| 147 | |
| 148 | struct obs_kernel_param { |
| 149 | const char *str; |
| 150 | int (*setup_func)(char *); |
| 151 | int early; |
| 152 | }; |
| 153 | |
| 154 | /* |
| 155 | * Only for really core code. See moduleparam.h for the normal way. |
| 156 | * |
| 157 | * Force the alignment so the compiler doesn't space elements of the |
| 158 | * obs_kernel_param "array" too far apart in .init.setup. |
| 159 | */ |
| 160 | #define __setup_param(str, unique_id, fn, early) \ |
| 161 | static char __setup_str_##unique_id[] __initdata = str; \ |
| 162 | static struct obs_kernel_param __setup_##unique_id \ |
| 163 | __attribute_used__ \ |
| 164 | __attribute__((__section__(".init.setup"))) \ |
| 165 | __attribute__((aligned((sizeof(long))))) \ |
| 166 | = { __setup_str_##unique_id, fn, early } |
| 167 | |
| 168 | #define __setup_null_param(str, unique_id) \ |
| 169 | __setup_param(str, unique_id, NULL, 0) |
| 170 | |
| 171 | #define __setup(str, fn) \ |
| 172 | __setup_param(str, fn, fn, 0) |
| 173 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 174 | /* NOTE: fn is as per module_param, not __setup! Emits warning if fn |
| 175 | * returns non-zero. */ |
| 176 | #define early_param(str, fn) \ |
| 177 | __setup_param(str, fn, fn, 1) |
| 178 | |
Alon Bar-Lev | 30d7e0d | 2007-02-12 00:53:52 -0800 | [diff] [blame] | 179 | /* Relies on boot_command_line being set */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 180 | void __init parse_early_param(void); |
| 181 | #endif /* __ASSEMBLY__ */ |
| 182 | |
| 183 | /** |
| 184 | * module_init() - driver initialization entry point |
| 185 | * @x: function to be run at kernel boot time or module insertion |
| 186 | * |
Robert P. J. Day | 72fd4a3 | 2007-02-10 01:45:59 -0800 | [diff] [blame] | 187 | * module_init() will either be called during do_initcalls() (if |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 188 | * builtin) or at module insertion time (if a module). There can only |
| 189 | * be one per module. |
| 190 | */ |
| 191 | #define module_init(x) __initcall(x); |
| 192 | |
| 193 | /** |
| 194 | * module_exit() - driver exit entry point |
| 195 | * @x: function to be run when driver is removed |
| 196 | * |
| 197 | * module_exit() will wrap the driver clean-up code |
| 198 | * with cleanup_module() when used with rmmod when |
| 199 | * the driver is a module. If the driver is statically |
| 200 | * compiled into the kernel, module_exit() has no effect. |
| 201 | * There can only be one per module. |
| 202 | */ |
| 203 | #define module_exit(x) __exitcall(x); |
| 204 | |
| 205 | #else /* MODULE */ |
| 206 | |
| 207 | /* Don't use these in modules, but some people do... */ |
| 208 | #define core_initcall(fn) module_init(fn) |
| 209 | #define postcore_initcall(fn) module_init(fn) |
| 210 | #define arch_initcall(fn) module_init(fn) |
| 211 | #define subsys_initcall(fn) module_init(fn) |
| 212 | #define fs_initcall(fn) module_init(fn) |
| 213 | #define device_initcall(fn) module_init(fn) |
| 214 | #define late_initcall(fn) module_init(fn) |
| 215 | |
| 216 | #define security_initcall(fn) module_init(fn) |
| 217 | |
| 218 | /* These macros create a dummy inline: gcc 2.9x does not count alias |
| 219 | as usage, hence the `unused function' warning when __init functions |
| 220 | are declared static. We use the dummy __*_module_inline functions |
| 221 | both to kill the warning and check the type of the init/cleanup |
| 222 | function. */ |
| 223 | |
| 224 | /* Each module must use one module_init(), or one no_module_init */ |
| 225 | #define module_init(initfn) \ |
| 226 | static inline initcall_t __inittest(void) \ |
| 227 | { return initfn; } \ |
| 228 | int init_module(void) __attribute__((alias(#initfn))); |
| 229 | |
| 230 | /* This is only required if you want to be unloadable. */ |
| 231 | #define module_exit(exitfn) \ |
| 232 | static inline exitcall_t __exittest(void) \ |
| 233 | { return exitfn; } \ |
| 234 | void cleanup_module(void) __attribute__((alias(#exitfn))); |
| 235 | |
| 236 | #define __setup_param(str, unique_id, fn) /* nothing */ |
| 237 | #define __setup_null_param(str, unique_id) /* nothing */ |
| 238 | #define __setup(str, func) /* nothing */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 239 | #endif |
| 240 | |
Johannes Berg | ab3bfca | 2007-05-06 14:50:49 -0700 | [diff] [blame] | 241 | /* Data marked not to be saved by software suspend */ |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 242 | #define __nosavedata __attribute__ ((__section__ (".data.nosave"))) |
| 243 | |
| 244 | /* This means "can be init if no module support, otherwise module load |
| 245 | may call it." */ |
| 246 | #ifdef CONFIG_MODULES |
| 247 | #define __init_or_module |
| 248 | #define __initdata_or_module |
| 249 | #else |
| 250 | #define __init_or_module __init |
| 251 | #define __initdata_or_module __initdata |
| 252 | #endif /*CONFIG_MODULES*/ |
| 253 | |
| 254 | #ifdef CONFIG_HOTPLUG |
| 255 | #define __devinit |
| 256 | #define __devinitdata |
| 257 | #define __devexit |
| 258 | #define __devexitdata |
| 259 | #else |
| 260 | #define __devinit __init |
| 261 | #define __devinitdata __initdata |
| 262 | #define __devexit __exit |
| 263 | #define __devexitdata __exitdata |
| 264 | #endif |
| 265 | |
Ashok Raj | e6982c6 | 2005-06-25 14:54:58 -0700 | [diff] [blame] | 266 | #ifdef CONFIG_HOTPLUG_CPU |
| 267 | #define __cpuinit |
| 268 | #define __cpuinitdata |
| 269 | #define __cpuexit |
| 270 | #define __cpuexitdata |
| 271 | #else |
| 272 | #define __cpuinit __init |
| 273 | #define __cpuinitdata __initdata |
| 274 | #define __cpuexit __exit |
| 275 | #define __cpuexitdata __exitdata |
| 276 | #endif |
| 277 | |
Andi Kleen | 9d99aaa | 2006-04-07 19:49:15 +0200 | [diff] [blame] | 278 | #if defined(CONFIG_MEMORY_HOTPLUG) || defined(CONFIG_ACPI_HOTPLUG_MEMORY) \ |
| 279 | || defined(CONFIG_ACPI_HOTPLUG_MEMORY_MODULE) |
Matt Tolentino | c09b424 | 2006-01-17 07:03:44 +0100 | [diff] [blame] | 280 | #define __meminit |
| 281 | #define __meminitdata |
| 282 | #define __memexit |
| 283 | #define __memexitdata |
| 284 | #else |
| 285 | #define __meminit __init |
| 286 | #define __meminitdata __initdata |
| 287 | #define __memexit __exit |
| 288 | #define __memexitdata __exitdata |
| 289 | #endif |
| 290 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 291 | /* Functions marked as __devexit may be discarded at kernel link time, depending |
| 292 | on config options. Newer versions of binutils detect references from |
| 293 | retained sections to discarded sections and flag an error. Pointers to |
| 294 | __devexit functions must use __devexit_p(function_name), the wrapper will |
| 295 | insert either the function_name or NULL, depending on the config options. |
| 296 | */ |
| 297 | #if defined(MODULE) || defined(CONFIG_HOTPLUG) |
| 298 | #define __devexit_p(x) x |
| 299 | #else |
| 300 | #define __devexit_p(x) NULL |
| 301 | #endif |
| 302 | |
| 303 | #ifdef MODULE |
| 304 | #define __exit_p(x) x |
| 305 | #else |
| 306 | #define __exit_p(x) NULL |
| 307 | #endif |
| 308 | |
| 309 | #endif /* _LINUX_INIT_H */ |