1 /*
2  * Helper macros to support writing architecture specific
3  * linker scripts.
4  *
5  * A minimal linker scripts has following content:
6  * [This is a sample, architectures may have special requiriements]
7  *
8  * OUTPUT_FORMAT(...)
9  * OUTPUT_ARCH(...)
10  * ENTRY(...)
11  * SECTIONS
12  * {
13  *	. = START;
14  *	__init_begin = .;
15  *	HEAD_TEXT_SECTION
16  *	INIT_TEXT_SECTION(PAGE_SIZE)
17  *	INIT_DATA_SECTION(...)
18  *	PERCPU_SECTION(CACHELINE_SIZE)
19  *	__init_end = .;
20  *
21  *	_stext = .;
22  *	TEXT_SECTION = 0
23  *	_etext = .;
24  *
25  *      _sdata = .;
26  *	RO_DATA_SECTION(PAGE_SIZE)
27  *	RW_DATA_SECTION(...)
28  *	_edata = .;
29  *
30  *	EXCEPTION_TABLE(...)
31  *	NOTES
32  *
33  *	BSS_SECTION(0, 0, 0)
34  *	_end = .;
35  *
36  *	STABS_DEBUG
37  *	DWARF_DEBUG
38  *
39  *	DISCARDS		// must be the last
40  * }
41  *
42  * [__init_begin, __init_end] is the init section that may be freed after init
43  * [_stext, _etext] is the text section
44  * [_sdata, _edata] is the data section
45  *
46  * Some of the included output section have their own set of constants.
47  * Examples are: [__initramfs_start, __initramfs_end] for initramfs and
48  *               [__nosave_begin, __nosave_end] for the nosave data
49  */
50 
51 #ifndef LOAD_OFFSET
52 #define LOAD_OFFSET 0
53 #endif
54 
55 #ifndef SYMBOL_PREFIX
56 #define VMLINUX_SYMBOL(sym) sym
57 #else
58 #define PASTE2(x,y) x##y
59 #define PASTE(x,y) PASTE2(x,y)
60 #define VMLINUX_SYMBOL(sym) PASTE(SYMBOL_PREFIX, sym)
61 #endif
62 
63 /* Align . to a 8 byte boundary equals to maximum function alignment. */
64 #define ALIGN_FUNCTION()  . = ALIGN(8)
65 
66 /*
67  * Align to a 32 byte boundary equal to the
68  * alignment gcc 4.5 uses for a struct
69  */
70 #define STRUCT_ALIGNMENT 32
71 #define STRUCT_ALIGN() . = ALIGN(STRUCT_ALIGNMENT)
72 
73 /* The actual configuration determine if the init/exit sections
74  * are handled as text/data or they can be discarded (which
75  * often happens at runtime)
76  */
77 #ifdef CONFIG_HOTPLUG
78 #define DEV_KEEP(sec)    *(.dev##sec)
79 #define DEV_DISCARD(sec)
80 #else
81 #define DEV_KEEP(sec)
82 #define DEV_DISCARD(sec) *(.dev##sec)
83 #endif
84 
85 #ifdef CONFIG_HOTPLUG_CPU
86 #define CPU_KEEP(sec)    *(.cpu##sec)
87 #define CPU_DISCARD(sec)
88 #else
89 #define CPU_KEEP(sec)
90 #define CPU_DISCARD(sec) *(.cpu##sec)
91 #endif
92 
93 #if defined(CONFIG_MEMORY_HOTPLUG)
94 #define MEM_KEEP(sec)    *(.mem##sec)
95 #define MEM_DISCARD(sec)
96 #else
97 #define MEM_KEEP(sec)
98 #define MEM_DISCARD(sec) *(.mem##sec)
99 #endif
100 
101 #ifdef CONFIG_FTRACE_MCOUNT_RECORD
102 #define MCOUNT_REC()	. = ALIGN(8);				\
103 			VMLINUX_SYMBOL(__start_mcount_loc) = .; \
104 			*(__mcount_loc)				\
105 			VMLINUX_SYMBOL(__stop_mcount_loc) = .;
106 #else
107 #define MCOUNT_REC()
108 #endif
109 
110 #ifdef CONFIG_TRACE_BRANCH_PROFILING
111 #define LIKELY_PROFILE()	VMLINUX_SYMBOL(__start_annotated_branch_profile) = .; \
112 				*(_ftrace_annotated_branch)			      \
113 				VMLINUX_SYMBOL(__stop_annotated_branch_profile) = .;
114 #else
115 #define LIKELY_PROFILE()
116 #endif
117 
118 #ifdef CONFIG_PROFILE_ALL_BRANCHES
119 #define BRANCH_PROFILE()	VMLINUX_SYMBOL(__start_branch_profile) = .;   \
120 				*(_ftrace_branch)			      \
121 				VMLINUX_SYMBOL(__stop_branch_profile) = .;
122 #else
123 #define BRANCH_PROFILE()
124 #endif
125 
126 #ifdef CONFIG_EVENT_TRACING
127 #define FTRACE_EVENTS()	. = ALIGN(8);					\
128 			VMLINUX_SYMBOL(__start_ftrace_events) = .;	\
129 			*(_ftrace_events)				\
130 			VMLINUX_SYMBOL(__stop_ftrace_events) = .;
131 #else
132 #define FTRACE_EVENTS()
133 #endif
134 
135 #ifdef CONFIG_TRACING
136 #define TRACE_PRINTKS() VMLINUX_SYMBOL(__start___trace_bprintk_fmt) = .;      \
137 			 *(__trace_printk_fmt) /* Trace_printk fmt' pointer */ \
138 			 VMLINUX_SYMBOL(__stop___trace_bprintk_fmt) = .;
139 #else
140 #define TRACE_PRINTKS()
141 #endif
142 
143 #ifdef CONFIG_FTRACE_SYSCALLS
144 #define TRACE_SYSCALLS() . = ALIGN(8);					\
145 			 VMLINUX_SYMBOL(__start_syscalls_metadata) = .;	\
146 			 *(__syscalls_metadata)				\
147 			 VMLINUX_SYMBOL(__stop_syscalls_metadata) = .;
148 #else
149 #define TRACE_SYSCALLS()
150 #endif
151 
152 
153 #define KERNEL_DTB()							\
154 	STRUCT_ALIGN();							\
155 	VMLINUX_SYMBOL(__dtb_start) = .;				\
156 	*(.dtb.init.rodata)						\
157 	VMLINUX_SYMBOL(__dtb_end) = .;
158 
159 /* .data section */
160 #define DATA_DATA							\
161 	*(.data)							\
162 	*(.ref.data)							\
163 	*(.data..shared_aligned) /* percpu related */			\
164 	DEV_KEEP(init.data)						\
165 	DEV_KEEP(exit.data)						\
166 	CPU_KEEP(init.data)						\
167 	CPU_KEEP(exit.data)						\
168 	MEM_KEEP(init.data)						\
169 	MEM_KEEP(exit.data)						\
170 	*(.data.unlikely)						\
171 	STRUCT_ALIGN();							\
172 	*(__tracepoints)						\
173 	/* implement dynamic printk debug */				\
174 	. = ALIGN(8);                                                   \
175 	VMLINUX_SYMBOL(__start___jump_table) = .;                       \
176 	*(__jump_table)                                                 \
177 	VMLINUX_SYMBOL(__stop___jump_table) = .;                        \
178 	. = ALIGN(8);							\
179 	VMLINUX_SYMBOL(__start___verbose) = .;                          \
180 	*(__verbose)                                                    \
181 	VMLINUX_SYMBOL(__stop___verbose) = .;				\
182 	LIKELY_PROFILE()		       				\
183 	BRANCH_PROFILE()						\
184 	TRACE_PRINTKS()
185 
186 /*
187  * Data section helpers
188  */
189 #define NOSAVE_DATA							\
190 	. = ALIGN(PAGE_SIZE);						\
191 	VMLINUX_SYMBOL(__nosave_begin) = .;				\
192 	*(.data..nosave)						\
193 	. = ALIGN(PAGE_SIZE);						\
194 	VMLINUX_SYMBOL(__nosave_end) = .;
195 
196 #define PAGE_ALIGNED_DATA(page_align)					\
197 	. = ALIGN(page_align);						\
198 	*(.data..page_aligned)
199 
200 #define READ_MOSTLY_DATA(align)						\
201 	. = ALIGN(align);						\
202 	*(.data..read_mostly)						\
203 	. = ALIGN(align);
204 
205 #define CACHELINE_ALIGNED_DATA(align)					\
206 	. = ALIGN(align);						\
207 	*(.data..cacheline_aligned)
208 
209 #define INIT_TASK_DATA(align)						\
210 	. = ALIGN(align);						\
211 	*(.data..init_task)
212 
213 /*
214  * Read only Data
215  */
216 #define RO_DATA_SECTION(align)						\
217 	. = ALIGN((align));						\
218 	.rodata           : AT(ADDR(.rodata) - LOAD_OFFSET) {		\
219 		VMLINUX_SYMBOL(__start_rodata) = .;			\
220 		*(.rodata) *(.rodata.*)					\
221 		*(__vermagic)		/* Kernel version magic */	\
222 		. = ALIGN(8);						\
223 		VMLINUX_SYMBOL(__start___tracepoints_ptrs) = .;		\
224 		*(__tracepoints_ptrs)	/* Tracepoints: pointer array */\
225 		VMLINUX_SYMBOL(__stop___tracepoints_ptrs) = .;		\
226 		*(__tracepoints_strings)/* Tracepoints: strings */	\
227 	}								\
228 									\
229 	.rodata1          : AT(ADDR(.rodata1) - LOAD_OFFSET) {		\
230 		*(.rodata1)						\
231 	}								\
232 									\
233 	BUG_TABLE							\
234 									\
235 	/* PCI quirks */						\
236 	.pci_fixup        : AT(ADDR(.pci_fixup) - LOAD_OFFSET) {	\
237 		VMLINUX_SYMBOL(__start_pci_fixups_early) = .;		\
238 		*(.pci_fixup_early)					\
239 		VMLINUX_SYMBOL(__end_pci_fixups_early) = .;		\
240 		VMLINUX_SYMBOL(__start_pci_fixups_header) = .;		\
241 		*(.pci_fixup_header)					\
242 		VMLINUX_SYMBOL(__end_pci_fixups_header) = .;		\
243 		VMLINUX_SYMBOL(__start_pci_fixups_final) = .;		\
244 		*(.pci_fixup_final)					\
245 		VMLINUX_SYMBOL(__end_pci_fixups_final) = .;		\
246 		VMLINUX_SYMBOL(__start_pci_fixups_enable) = .;		\
247 		*(.pci_fixup_enable)					\
248 		VMLINUX_SYMBOL(__end_pci_fixups_enable) = .;		\
249 		VMLINUX_SYMBOL(__start_pci_fixups_resume) = .;		\
250 		*(.pci_fixup_resume)					\
251 		VMLINUX_SYMBOL(__end_pci_fixups_resume) = .;		\
252 		VMLINUX_SYMBOL(__start_pci_fixups_resume_early) = .;	\
253 		*(.pci_fixup_resume_early)				\
254 		VMLINUX_SYMBOL(__end_pci_fixups_resume_early) = .;	\
255 		VMLINUX_SYMBOL(__start_pci_fixups_suspend) = .;		\
256 		*(.pci_fixup_suspend)					\
257 		VMLINUX_SYMBOL(__end_pci_fixups_suspend) = .;		\
258 	}								\
259 									\
260 	/* Built-in firmware blobs */					\
261 	.builtin_fw        : AT(ADDR(.builtin_fw) - LOAD_OFFSET) {	\
262 		VMLINUX_SYMBOL(__start_builtin_fw) = .;			\
263 		*(.builtin_fw)						\
264 		VMLINUX_SYMBOL(__end_builtin_fw) = .;			\
265 	}								\
266 									\
267 	/* RapidIO route ops */						\
268 	.rio_ops        : AT(ADDR(.rio_ops) - LOAD_OFFSET) {		\
269 		VMLINUX_SYMBOL(__start_rio_switch_ops) = .;		\
270 		*(.rio_switch_ops)					\
271 		VMLINUX_SYMBOL(__end_rio_switch_ops) = .;		\
272 	}								\
273 									\
274 	TRACEDATA							\
275 									\
276 	/* Kernel symbol table: Normal symbols */			\
277 	__ksymtab         : AT(ADDR(__ksymtab) - LOAD_OFFSET) {		\
278 		VMLINUX_SYMBOL(__start___ksymtab) = .;			\
279 		*(SORT(___ksymtab+*))					\
280 		VMLINUX_SYMBOL(__stop___ksymtab) = .;			\
281 	}								\
282 									\
283 	/* Kernel symbol table: GPL-only symbols */			\
284 	__ksymtab_gpl     : AT(ADDR(__ksymtab_gpl) - LOAD_OFFSET) {	\
285 		VMLINUX_SYMBOL(__start___ksymtab_gpl) = .;		\
286 		*(SORT(___ksymtab_gpl+*))				\
287 		VMLINUX_SYMBOL(__stop___ksymtab_gpl) = .;		\
288 	}								\
289 									\
290 	/* Kernel symbol table: Normal unused symbols */		\
291 	__ksymtab_unused  : AT(ADDR(__ksymtab_unused) - LOAD_OFFSET) {	\
292 		VMLINUX_SYMBOL(__start___ksymtab_unused) = .;		\
293 		*(SORT(___ksymtab_unused+*))				\
294 		VMLINUX_SYMBOL(__stop___ksymtab_unused) = .;		\
295 	}								\
296 									\
297 	/* Kernel symbol table: GPL-only unused symbols */		\
298 	__ksymtab_unused_gpl : AT(ADDR(__ksymtab_unused_gpl) - LOAD_OFFSET) { \
299 		VMLINUX_SYMBOL(__start___ksymtab_unused_gpl) = .;	\
300 		*(SORT(___ksymtab_unused_gpl+*))			\
301 		VMLINUX_SYMBOL(__stop___ksymtab_unused_gpl) = .;	\
302 	}								\
303 									\
304 	/* Kernel symbol table: GPL-future-only symbols */		\
305 	__ksymtab_gpl_future : AT(ADDR(__ksymtab_gpl_future) - LOAD_OFFSET) { \
306 		VMLINUX_SYMBOL(__start___ksymtab_gpl_future) = .;	\
307 		*(SORT(___ksymtab_gpl_future+*))			\
308 		VMLINUX_SYMBOL(__stop___ksymtab_gpl_future) = .;	\
309 	}								\
310 									\
311 	/* Kernel symbol table: Normal symbols */			\
312 	__kcrctab         : AT(ADDR(__kcrctab) - LOAD_OFFSET) {		\
313 		VMLINUX_SYMBOL(__start___kcrctab) = .;			\
314 		*(SORT(___kcrctab+*))					\
315 		VMLINUX_SYMBOL(__stop___kcrctab) = .;			\
316 	}								\
317 									\
318 	/* Kernel symbol table: GPL-only symbols */			\
319 	__kcrctab_gpl     : AT(ADDR(__kcrctab_gpl) - LOAD_OFFSET) {	\
320 		VMLINUX_SYMBOL(__start___kcrctab_gpl) = .;		\
321 		*(SORT(___kcrctab_gpl+*))				\
322 		VMLINUX_SYMBOL(__stop___kcrctab_gpl) = .;		\
323 	}								\
324 									\
325 	/* Kernel symbol table: Normal unused symbols */		\
326 	__kcrctab_unused  : AT(ADDR(__kcrctab_unused) - LOAD_OFFSET) {	\
327 		VMLINUX_SYMBOL(__start___kcrctab_unused) = .;		\
328 		*(SORT(___kcrctab_unused+*))				\
329 		VMLINUX_SYMBOL(__stop___kcrctab_unused) = .;		\
330 	}								\
331 									\
332 	/* Kernel symbol table: GPL-only unused symbols */		\
333 	__kcrctab_unused_gpl : AT(ADDR(__kcrctab_unused_gpl) - LOAD_OFFSET) { \
334 		VMLINUX_SYMBOL(__start___kcrctab_unused_gpl) = .;	\
335 		*(SORT(___kcrctab_unused_gpl+*))			\
336 		VMLINUX_SYMBOL(__stop___kcrctab_unused_gpl) = .;	\
337 	}								\
338 									\
339 	/* Kernel symbol table: GPL-future-only symbols */		\
340 	__kcrctab_gpl_future : AT(ADDR(__kcrctab_gpl_future) - LOAD_OFFSET) { \
341 		VMLINUX_SYMBOL(__start___kcrctab_gpl_future) = .;	\
342 		*(SORT(___kcrctab_gpl_future+*))			\
343 		VMLINUX_SYMBOL(__stop___kcrctab_gpl_future) = .;	\
344 	}								\
345 									\
346 	/* Kernel symbol table: strings */				\
347         __ksymtab_strings : AT(ADDR(__ksymtab_strings) - LOAD_OFFSET) {	\
348 		*(__ksymtab_strings)					\
349 	}								\
350 									\
351 	/* __*init sections */						\
352 	__init_rodata : AT(ADDR(__init_rodata) - LOAD_OFFSET) {		\
353 		*(.ref.rodata)						\
354 		DEV_KEEP(init.rodata)					\
355 		DEV_KEEP(exit.rodata)					\
356 		CPU_KEEP(init.rodata)					\
357 		CPU_KEEP(exit.rodata)					\
358 		MEM_KEEP(init.rodata)					\
359 		MEM_KEEP(exit.rodata)					\
360 	}								\
361 									\
362 	/* Built-in module parameters. */				\
363 	__param : AT(ADDR(__param) - LOAD_OFFSET) {			\
364 		VMLINUX_SYMBOL(__start___param) = .;			\
365 		*(__param)						\
366 		VMLINUX_SYMBOL(__stop___param) = .;			\
367 	}								\
368 									\
369 	/* Built-in module versions. */					\
370 	__modver : AT(ADDR(__modver) - LOAD_OFFSET) {			\
371 		VMLINUX_SYMBOL(__start___modver) = .;			\
372 		*(__modver)						\
373 		VMLINUX_SYMBOL(__stop___modver) = .;			\
374 		. = ALIGN((align));					\
375 		VMLINUX_SYMBOL(__end_rodata) = .;			\
376 	}								\
377 	. = ALIGN((align));
378 
379 /* RODATA & RO_DATA provided for backward compatibility.
380  * All archs are supposed to use RO_DATA() */
381 #define RODATA          RO_DATA_SECTION(4096)
382 #define RO_DATA(align)  RO_DATA_SECTION(align)
383 
384 #define SECURITY_INIT							\
385 	.security_initcall.init : AT(ADDR(.security_initcall.init) - LOAD_OFFSET) { \
386 		VMLINUX_SYMBOL(__security_initcall_start) = .;		\
387 		*(.security_initcall.init) 				\
388 		VMLINUX_SYMBOL(__security_initcall_end) = .;		\
389 	}
390 
391 /* .text section. Map to function alignment to avoid address changes
392  * during second ld run in second ld pass when generating System.map */
393 #define TEXT_TEXT							\
394 		ALIGN_FUNCTION();					\
395 		*(.text.hot)						\
396 		*(.text)						\
397 		*(.ref.text)						\
398 	DEV_KEEP(init.text)						\
399 	DEV_KEEP(exit.text)						\
400 	CPU_KEEP(init.text)						\
401 	CPU_KEEP(exit.text)						\
402 	MEM_KEEP(init.text)						\
403 	MEM_KEEP(exit.text)						\
404 		*(.text.unlikely)
405 
406 
407 /* sched.text is aling to function alignment to secure we have same
408  * address even at second ld pass when generating System.map */
409 #define SCHED_TEXT							\
410 		ALIGN_FUNCTION();					\
411 		VMLINUX_SYMBOL(__sched_text_start) = .;			\
412 		*(.sched.text)						\
413 		VMLINUX_SYMBOL(__sched_text_end) = .;
414 
415 /* spinlock.text is aling to function alignment to secure we have same
416  * address even at second ld pass when generating System.map */
417 #define LOCK_TEXT							\
418 		ALIGN_FUNCTION();					\
419 		VMLINUX_SYMBOL(__lock_text_start) = .;			\
420 		*(.spinlock.text)					\
421 		VMLINUX_SYMBOL(__lock_text_end) = .;
422 
423 #define KPROBES_TEXT							\
424 		ALIGN_FUNCTION();					\
425 		VMLINUX_SYMBOL(__kprobes_text_start) = .;		\
426 		*(.kprobes.text)					\
427 		VMLINUX_SYMBOL(__kprobes_text_end) = .;
428 
429 #define ENTRY_TEXT							\
430 		ALIGN_FUNCTION();					\
431 		VMLINUX_SYMBOL(__entry_text_start) = .;			\
432 		*(.entry.text)						\
433 		VMLINUX_SYMBOL(__entry_text_end) = .;
434 
435 #ifdef CONFIG_FUNCTION_GRAPH_TRACER
436 #define IRQENTRY_TEXT							\
437 		ALIGN_FUNCTION();					\
438 		VMLINUX_SYMBOL(__irqentry_text_start) = .;		\
439 		*(.irqentry.text)					\
440 		VMLINUX_SYMBOL(__irqentry_text_end) = .;
441 #else
442 #define IRQENTRY_TEXT
443 #endif
444 
445 /* Section used for early init (in .S files) */
446 #define HEAD_TEXT  *(.head.text)
447 
448 #define HEAD_TEXT_SECTION							\
449 	.head.text : AT(ADDR(.head.text) - LOAD_OFFSET) {		\
450 		HEAD_TEXT						\
451 	}
452 
453 /*
454  * Exception table
455  */
456 #define EXCEPTION_TABLE(align)						\
457 	. = ALIGN(align);						\
458 	__ex_table : AT(ADDR(__ex_table) - LOAD_OFFSET) {		\
459 		VMLINUX_SYMBOL(__start___ex_table) = .;			\
460 		*(__ex_table)						\
461 		VMLINUX_SYMBOL(__stop___ex_table) = .;			\
462 	}
463 
464 /*
465  * Init task
466  */
467 #define INIT_TASK_DATA_SECTION(align)					\
468 	. = ALIGN(align);						\
469 	.data..init_task :  AT(ADDR(.data..init_task) - LOAD_OFFSET) {	\
470 		INIT_TASK_DATA(align)					\
471 	}
472 
473 #ifdef CONFIG_CONSTRUCTORS
474 #define KERNEL_CTORS()	. = ALIGN(8);			   \
475 			VMLINUX_SYMBOL(__ctors_start) = .; \
476 			*(.ctors)			   \
477 			VMLINUX_SYMBOL(__ctors_end) = .;
478 #else
479 #define KERNEL_CTORS()
480 #endif
481 
482 /* init and exit section handling */
483 #define INIT_DATA							\
484 	*(.init.data)							\
485 	DEV_DISCARD(init.data)						\
486 	CPU_DISCARD(init.data)						\
487 	MEM_DISCARD(init.data)						\
488 	KERNEL_CTORS()							\
489 	MCOUNT_REC()							\
490 	*(.init.rodata)							\
491 	FTRACE_EVENTS()							\
492 	TRACE_SYSCALLS()						\
493 	DEV_DISCARD(init.rodata)					\
494 	CPU_DISCARD(init.rodata)					\
495 	MEM_DISCARD(init.rodata)					\
496 	KERNEL_DTB()
497 
498 #define INIT_TEXT							\
499 	*(.init.text)							\
500 	DEV_DISCARD(init.text)						\
501 	CPU_DISCARD(init.text)						\
502 	MEM_DISCARD(init.text)
503 
504 #define EXIT_DATA							\
505 	*(.exit.data)							\
506 	DEV_DISCARD(exit.data)						\
507 	DEV_DISCARD(exit.rodata)					\
508 	CPU_DISCARD(exit.data)						\
509 	CPU_DISCARD(exit.rodata)					\
510 	MEM_DISCARD(exit.data)						\
511 	MEM_DISCARD(exit.rodata)
512 
513 #define EXIT_TEXT							\
514 	*(.exit.text)							\
515 	DEV_DISCARD(exit.text)						\
516 	CPU_DISCARD(exit.text)						\
517 	MEM_DISCARD(exit.text)
518 
519 #define EXIT_CALL							\
520 	*(.exitcall.exit)
521 
522 /*
523  * bss (Block Started by Symbol) - uninitialized data
524  * zeroed during startup
525  */
526 #define SBSS(sbss_align)						\
527 	. = ALIGN(sbss_align);						\
528 	.sbss : AT(ADDR(.sbss) - LOAD_OFFSET) {				\
529 		*(.sbss)						\
530 		*(.scommon)						\
531 	}
532 
533 #define BSS(bss_align)							\
534 	. = ALIGN(bss_align);						\
535 	.bss : AT(ADDR(.bss) - LOAD_OFFSET) {				\
536 		*(.bss..page_aligned)					\
537 		*(.dynbss)						\
538 		*(.bss)							\
539 		*(COMMON)						\
540 	}
541 
542 /*
543  * DWARF debug sections.
544  * Symbols in the DWARF debugging sections are relative to
545  * the beginning of the section so we begin them at 0.
546  */
547 #define DWARF_DEBUG							\
548 		/* DWARF 1 */						\
549 		.debug          0 : { *(.debug) }			\
550 		.line           0 : { *(.line) }			\
551 		/* GNU DWARF 1 extensions */				\
552 		.debug_srcinfo  0 : { *(.debug_srcinfo) }		\
553 		.debug_sfnames  0 : { *(.debug_sfnames) }		\
554 		/* DWARF 1.1 and DWARF 2 */				\
555 		.debug_aranges  0 : { *(.debug_aranges) }		\
556 		.debug_pubnames 0 : { *(.debug_pubnames) }		\
557 		/* DWARF 2 */						\
558 		.debug_info     0 : { *(.debug_info			\
559 				.gnu.linkonce.wi.*) }			\
560 		.debug_abbrev   0 : { *(.debug_abbrev) }		\
561 		.debug_line     0 : { *(.debug_line) }			\
562 		.debug_frame    0 : { *(.debug_frame) }			\
563 		.debug_str      0 : { *(.debug_str) }			\
564 		.debug_loc      0 : { *(.debug_loc) }			\
565 		.debug_macinfo  0 : { *(.debug_macinfo) }		\
566 		/* SGI/MIPS DWARF 2 extensions */			\
567 		.debug_weaknames 0 : { *(.debug_weaknames) }		\
568 		.debug_funcnames 0 : { *(.debug_funcnames) }		\
569 		.debug_typenames 0 : { *(.debug_typenames) }		\
570 		.debug_varnames  0 : { *(.debug_varnames) }		\
571 
572 		/* Stabs debugging sections.  */
573 #define STABS_DEBUG							\
574 		.stab 0 : { *(.stab) }					\
575 		.stabstr 0 : { *(.stabstr) }				\
576 		.stab.excl 0 : { *(.stab.excl) }			\
577 		.stab.exclstr 0 : { *(.stab.exclstr) }			\
578 		.stab.index 0 : { *(.stab.index) }			\
579 		.stab.indexstr 0 : { *(.stab.indexstr) }		\
580 		.comment 0 : { *(.comment) }
581 
582 #ifdef CONFIG_GENERIC_BUG
583 #define BUG_TABLE							\
584 	. = ALIGN(8);							\
585 	__bug_table : AT(ADDR(__bug_table) - LOAD_OFFSET) {		\
586 		VMLINUX_SYMBOL(__start___bug_table) = .;		\
587 		*(__bug_table)						\
588 		VMLINUX_SYMBOL(__stop___bug_table) = .;			\
589 	}
590 #else
591 #define BUG_TABLE
592 #endif
593 
594 #ifdef CONFIG_PM_TRACE
595 #define TRACEDATA							\
596 	. = ALIGN(4);							\
597 	.tracedata : AT(ADDR(.tracedata) - LOAD_OFFSET) {		\
598 		VMLINUX_SYMBOL(__tracedata_start) = .;			\
599 		*(.tracedata)						\
600 		VMLINUX_SYMBOL(__tracedata_end) = .;			\
601 	}
602 #else
603 #define TRACEDATA
604 #endif
605 
606 #define NOTES								\
607 	.notes : AT(ADDR(.notes) - LOAD_OFFSET) {			\
608 		VMLINUX_SYMBOL(__start_notes) = .;			\
609 		*(.note.*)						\
610 		VMLINUX_SYMBOL(__stop_notes) = .;			\
611 	}
612 
613 #define INIT_SETUP(initsetup_align)					\
614 		. = ALIGN(initsetup_align);				\
615 		VMLINUX_SYMBOL(__setup_start) = .;			\
616 		*(.init.setup)						\
617 		VMLINUX_SYMBOL(__setup_end) = .;
618 
619 #define INIT_CALLS_LEVEL(level)						\
620 		VMLINUX_SYMBOL(__initcall##level##_start) = .;		\
621 		*(.initcall##level##.init)				\
622 		*(.initcall##level##s.init)				\
623 
624 #define INIT_CALLS							\
625 		VMLINUX_SYMBOL(__initcall_start) = .;			\
626 		*(.initcallearly.init)					\
627 		INIT_CALLS_LEVEL(0)					\
628 		INIT_CALLS_LEVEL(1)					\
629 		INIT_CALLS_LEVEL(2)					\
630 		INIT_CALLS_LEVEL(3)					\
631 		INIT_CALLS_LEVEL(4)					\
632 		INIT_CALLS_LEVEL(5)					\
633 		INIT_CALLS_LEVEL(rootfs)				\
634 		INIT_CALLS_LEVEL(6)					\
635 		INIT_CALLS_LEVEL(7)					\
636 		VMLINUX_SYMBOL(__initcall_end) = .;
637 
638 #define CON_INITCALL							\
639 		VMLINUX_SYMBOL(__con_initcall_start) = .;		\
640 		*(.con_initcall.init)					\
641 		VMLINUX_SYMBOL(__con_initcall_end) = .;
642 
643 #define SECURITY_INITCALL						\
644 		VMLINUX_SYMBOL(__security_initcall_start) = .;		\
645 		*(.security_initcall.init)				\
646 		VMLINUX_SYMBOL(__security_initcall_end) = .;
647 
648 #ifdef CONFIG_BLK_DEV_INITRD
649 #define INIT_RAM_FS							\
650 	. = ALIGN(4);							\
651 	VMLINUX_SYMBOL(__initramfs_start) = .;				\
652 	*(.init.ramfs)							\
653 	. = ALIGN(8);							\
654 	*(.init.ramfs.info)
655 #else
656 #define INIT_RAM_FS
657 #endif
658 
659 /*
660  * Default discarded sections.
661  *
662  * Some archs want to discard exit text/data at runtime rather than
663  * link time due to cross-section references such as alt instructions,
664  * bug table, eh_frame, etc.  DISCARDS must be the last of output
665  * section definitions so that such archs put those in earlier section
666  * definitions.
667  */
668 #define DISCARDS							\
669 	/DISCARD/ : {							\
670 	EXIT_TEXT							\
671 	EXIT_DATA							\
672 	EXIT_CALL							\
673 	*(.discard)							\
674 	*(.discard.*)							\
675 	}
676 
677 /**
678  * PERCPU_INPUT - the percpu input sections
679  * @cacheline: cacheline size
680  *
681  * The core percpu section names and core symbols which do not rely
682  * directly upon load addresses.
683  *
684  * @cacheline is used to align subsections to avoid false cacheline
685  * sharing between subsections for different purposes.
686  */
687 #define PERCPU_INPUT(cacheline)						\
688 	VMLINUX_SYMBOL(__per_cpu_start) = .;				\
689 	*(.data..percpu..first)						\
690 	. = ALIGN(PAGE_SIZE);						\
691 	*(.data..percpu..page_aligned)					\
692 	. = ALIGN(cacheline);						\
693 	*(.data..percpu..readmostly)					\
694 	. = ALIGN(cacheline);						\
695 	*(.data..percpu)						\
696 	*(.data..percpu..shared_aligned)				\
697 	VMLINUX_SYMBOL(__per_cpu_end) = .;
698 
699 /**
700  * PERCPU_VADDR - define output section for percpu area
701  * @cacheline: cacheline size
702  * @vaddr: explicit base address (optional)
703  * @phdr: destination PHDR (optional)
704  *
705  * Macro which expands to output section for percpu area.
706  *
707  * @cacheline is used to align subsections to avoid false cacheline
708  * sharing between subsections for different purposes.
709  *
710  * If @vaddr is not blank, it specifies explicit base address and all
711  * percpu symbols will be offset from the given address.  If blank,
712  * @vaddr always equals @laddr + LOAD_OFFSET.
713  *
714  * @phdr defines the output PHDR to use if not blank.  Be warned that
715  * output PHDR is sticky.  If @phdr is specified, the next output
716  * section in the linker script will go there too.  @phdr should have
717  * a leading colon.
718  *
719  * Note that this macros defines __per_cpu_load as an absolute symbol.
720  * If there is no need to put the percpu section at a predetermined
721  * address, use PERCPU_SECTION.
722  */
723 #define PERCPU_VADDR(cacheline, vaddr, phdr)				\
724 	VMLINUX_SYMBOL(__per_cpu_load) = .;				\
725 	.data..percpu vaddr : AT(VMLINUX_SYMBOL(__per_cpu_load)		\
726 				- LOAD_OFFSET) {			\
727 		PERCPU_INPUT(cacheline)					\
728 	} phdr								\
729 	. = VMLINUX_SYMBOL(__per_cpu_load) + SIZEOF(.data..percpu);
730 
731 /**
732  * PERCPU_SECTION - define output section for percpu area, simple version
733  * @cacheline: cacheline size
734  *
735  * Align to PAGE_SIZE and outputs output section for percpu area.  This
736  * macro doesn't manipulate @vaddr or @phdr and __per_cpu_load and
737  * __per_cpu_start will be identical.
738  *
739  * This macro is equivalent to ALIGN(PAGE_SIZE); PERCPU_VADDR(@cacheline,,)
740  * except that __per_cpu_load is defined as a relative symbol against
741  * .data..percpu which is required for relocatable x86_32 configuration.
742  */
743 #define PERCPU_SECTION(cacheline)					\
744 	. = ALIGN(PAGE_SIZE);						\
745 	.data..percpu	: AT(ADDR(.data..percpu) - LOAD_OFFSET) {	\
746 		VMLINUX_SYMBOL(__per_cpu_load) = .;			\
747 		PERCPU_INPUT(cacheline)					\
748 	}
749 
750 
751 /*
752  * Definition of the high level *_SECTION macros
753  * They will fit only a subset of the architectures
754  */
755 
756 
757 /*
758  * Writeable data.
759  * All sections are combined in a single .data section.
760  * The sections following CONSTRUCTORS are arranged so their
761  * typical alignment matches.
762  * A cacheline is typical/always less than a PAGE_SIZE so
763  * the sections that has this restriction (or similar)
764  * is located before the ones requiring PAGE_SIZE alignment.
765  * NOSAVE_DATA starts and ends with a PAGE_SIZE alignment which
766  * matches the requirement of PAGE_ALIGNED_DATA.
767  *
768  * use 0 as page_align if page_aligned data is not used */
769 #define RW_DATA_SECTION(cacheline, pagealigned, inittask)		\
770 	. = ALIGN(PAGE_SIZE);						\
771 	.data : AT(ADDR(.data) - LOAD_OFFSET) {				\
772 		INIT_TASK_DATA(inittask)				\
773 		NOSAVE_DATA						\
774 		PAGE_ALIGNED_DATA(pagealigned)				\
775 		CACHELINE_ALIGNED_DATA(cacheline)			\
776 		READ_MOSTLY_DATA(cacheline)				\
777 		DATA_DATA						\
778 		CONSTRUCTORS						\
779 	}
780 
781 #define INIT_TEXT_SECTION(inittext_align)				\
782 	. = ALIGN(inittext_align);					\
783 	.init.text : AT(ADDR(.init.text) - LOAD_OFFSET) {		\
784 		VMLINUX_SYMBOL(_sinittext) = .;				\
785 		INIT_TEXT						\
786 		VMLINUX_SYMBOL(_einittext) = .;				\
787 	}
788 
789 #define INIT_DATA_SECTION(initsetup_align)				\
790 	.init.data : AT(ADDR(.init.data) - LOAD_OFFSET) {		\
791 		INIT_DATA						\
792 		INIT_SETUP(initsetup_align)				\
793 		INIT_CALLS						\
794 		CON_INITCALL						\
795 		SECURITY_INITCALL					\
796 		INIT_RAM_FS						\
797 	}
798 
799 #define BSS_SECTION(sbss_align, bss_align, stop_align)			\
800 	. = ALIGN(sbss_align);						\
801 	VMLINUX_SYMBOL(__bss_start) = .;				\
802 	SBSS(sbss_align)						\
803 	BSS(bss_align)							\
804 	. = ALIGN(stop_align);						\
805 	VMLINUX_SYMBOL(__bss_stop) = .;
806