linux-brain/arch/x86/kernel/vmlinux.lds.S
Tejun Heo 023bf6f1b8 linker script: unify usage of discard definition
Discarded sections in different archs share some commonality but have
considerable differences.  This led to linker script for each arch
implementing its own /DISCARD/ definition, which makes maintaining
tedious and adding new entries error-prone.

This patch makes all linker scripts to move discard definitions to the
end of the linker script and use the common DISCARDS macro.  As ld
uses the first matching section definition, archs can include default
discarded sections by including them earlier in the linker script.

ia64 is notable because it first throws away some ia64 specific
subsections and then include the rest of the sections into the final
image, so those sections must be discarded before the inclusion.

defconfig compile tested for x86, x86-64, powerpc, powerpc64, ia64,
alpha, sparc, sparc64 and s390.  Michal Simek tested microblaze.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Tested-by: Michal Simek <monstr@monstr.eu>
Cc: linux-arch@vger.kernel.org
Cc: Michal Simek <monstr@monstr.eu>
Cc: microblaze-uclinux@itee.uq.edu.au
Cc: Sam Ravnborg <sam@ravnborg.org>
Cc: Tony Luck <tony.luck@intel.com>
2009-07-09 11:27:40 +09:00

431 lines
9.5 KiB
ArmAsm

/*
* ld script for the x86 kernel
*
* Historic 32-bit version written by Martin Mares <mj@atrey.karlin.mff.cuni.cz>
*
* Modernisation, unification and other changes and fixes:
* Copyright (C) 2007-2009 Sam Ravnborg <sam@ravnborg.org>
*
*
* Don't define absolute symbols until and unless you know that symbol
* value is should remain constant even if kernel image is relocated
* at run time. Absolute symbols are not relocated. If symbol value should
* change if kernel is relocated, make the symbol section relative and
* put it inside the section definition.
*/
#ifdef CONFIG_X86_32
#define LOAD_OFFSET __PAGE_OFFSET
#else
#define LOAD_OFFSET __START_KERNEL_map
#endif
#include <asm-generic/vmlinux.lds.h>
#include <asm/asm-offsets.h>
#include <asm/thread_info.h>
#include <asm/page_types.h>
#include <asm/cache.h>
#include <asm/boot.h>
#undef i386 /* in case the preprocessor is a 32bit one */
OUTPUT_FORMAT(CONFIG_OUTPUT_FORMAT, CONFIG_OUTPUT_FORMAT, CONFIG_OUTPUT_FORMAT)
#ifdef CONFIG_X86_32
OUTPUT_ARCH(i386)
ENTRY(phys_startup_32)
jiffies = jiffies_64;
#else
OUTPUT_ARCH(i386:x86-64)
ENTRY(phys_startup_64)
jiffies_64 = jiffies;
#endif
PHDRS {
text PT_LOAD FLAGS(5); /* R_E */
data PT_LOAD FLAGS(7); /* RWE */
#ifdef CONFIG_X86_64
user PT_LOAD FLAGS(7); /* RWE */
data.init PT_LOAD FLAGS(7); /* RWE */
#ifdef CONFIG_SMP
percpu PT_LOAD FLAGS(7); /* RWE */
#endif
data.init2 PT_LOAD FLAGS(7); /* RWE */
#endif
note PT_NOTE FLAGS(0); /* ___ */
}
SECTIONS
{
#ifdef CONFIG_X86_32
. = LOAD_OFFSET + LOAD_PHYSICAL_ADDR;
phys_startup_32 = startup_32 - LOAD_OFFSET;
#else
. = __START_KERNEL;
phys_startup_64 = startup_64 - LOAD_OFFSET;
#endif
/* Text and read-only data */
/* bootstrapping code */
.text.head : AT(ADDR(.text.head) - LOAD_OFFSET) {
_text = .;
*(.text.head)
} :text = 0x9090
/* The rest of the text */
.text : AT(ADDR(.text) - LOAD_OFFSET) {
#ifdef CONFIG_X86_32
/* not really needed, already page aligned */
. = ALIGN(PAGE_SIZE);
*(.text.page_aligned)
#endif
. = ALIGN(8);
_stext = .;
TEXT_TEXT
SCHED_TEXT
LOCK_TEXT
KPROBES_TEXT
IRQENTRY_TEXT
*(.fixup)
*(.gnu.warning)
/* End of text section */
_etext = .;
} :text = 0x9090
NOTES :text :note
/* Exception table */
. = ALIGN(16);
__ex_table : AT(ADDR(__ex_table) - LOAD_OFFSET) {
__start___ex_table = .;
*(__ex_table)
__stop___ex_table = .;
} :text = 0x9090
RODATA
/* Data */
. = ALIGN(PAGE_SIZE);
.data : AT(ADDR(.data) - LOAD_OFFSET) {
/* Start of data section */
_sdata = .;
DATA_DATA
CONSTRUCTORS
#ifdef CONFIG_X86_64
/* End of data section */
_edata = .;
#endif
} :data
#ifdef CONFIG_X86_32
/* 32 bit has nosave before _edata */
. = ALIGN(PAGE_SIZE);
.data_nosave : AT(ADDR(.data_nosave) - LOAD_OFFSET) {
__nosave_begin = .;
*(.data.nosave)
. = ALIGN(PAGE_SIZE);
__nosave_end = .;
}
#endif
. = ALIGN(PAGE_SIZE);
.data.page_aligned : AT(ADDR(.data.page_aligned) - LOAD_OFFSET) {
*(.data.page_aligned)
*(.data.idt)
}
#ifdef CONFIG_X86_32
. = ALIGN(32);
#else
. = ALIGN(PAGE_SIZE);
. = ALIGN(CONFIG_X86_L1_CACHE_BYTES);
#endif
.data.cacheline_aligned :
AT(ADDR(.data.cacheline_aligned) - LOAD_OFFSET) {
*(.data.cacheline_aligned)
}
/* rarely changed data like cpu maps */
#ifdef CONFIG_X86_32
. = ALIGN(32);
#else
. = ALIGN(CONFIG_X86_INTERNODE_CACHE_BYTES);
#endif
.data.read_mostly : AT(ADDR(.data.read_mostly) - LOAD_OFFSET) {
*(.data.read_mostly)
#ifdef CONFIG_X86_32
/* End of data section */
_edata = .;
#endif
}
#ifdef CONFIG_X86_64
#define VSYSCALL_ADDR (-10*1024*1024)
#define VSYSCALL_PHYS_ADDR ((LOADADDR(.data.read_mostly) + \
SIZEOF(.data.read_mostly) + 4095) & ~(4095))
#define VSYSCALL_VIRT_ADDR ((ADDR(.data.read_mostly) + \
SIZEOF(.data.read_mostly) + 4095) & ~(4095))
#define VLOAD_OFFSET (VSYSCALL_ADDR - VSYSCALL_PHYS_ADDR)
#define VLOAD(x) (ADDR(x) - VLOAD_OFFSET)
#define VVIRT_OFFSET (VSYSCALL_ADDR - VSYSCALL_VIRT_ADDR)
#define VVIRT(x) (ADDR(x) - VVIRT_OFFSET)
. = VSYSCALL_ADDR;
.vsyscall_0 : AT(VSYSCALL_PHYS_ADDR) {
*(.vsyscall_0)
} :user
__vsyscall_0 = VSYSCALL_VIRT_ADDR;
. = ALIGN(CONFIG_X86_L1_CACHE_BYTES);
.vsyscall_fn : AT(VLOAD(.vsyscall_fn)) {
*(.vsyscall_fn)
}
. = ALIGN(CONFIG_X86_L1_CACHE_BYTES);
.vsyscall_gtod_data : AT(VLOAD(.vsyscall_gtod_data)) {
*(.vsyscall_gtod_data)
}
vsyscall_gtod_data = VVIRT(.vsyscall_gtod_data);
.vsyscall_clock : AT(VLOAD(.vsyscall_clock)) {
*(.vsyscall_clock)
}
vsyscall_clock = VVIRT(.vsyscall_clock);
.vsyscall_1 ADDR(.vsyscall_0) + 1024: AT(VLOAD(.vsyscall_1)) {
*(.vsyscall_1)
}
.vsyscall_2 ADDR(.vsyscall_0) + 2048: AT(VLOAD(.vsyscall_2)) {
*(.vsyscall_2)
}
.vgetcpu_mode : AT(VLOAD(.vgetcpu_mode)) {
*(.vgetcpu_mode)
}
vgetcpu_mode = VVIRT(.vgetcpu_mode);
. = ALIGN(CONFIG_X86_L1_CACHE_BYTES);
.jiffies : AT(VLOAD(.jiffies)) {
*(.jiffies)
}
jiffies = VVIRT(.jiffies);
.vsyscall_3 ADDR(.vsyscall_0) + 3072: AT(VLOAD(.vsyscall_3)) {
*(.vsyscall_3)
}
. = VSYSCALL_VIRT_ADDR + PAGE_SIZE;
#undef VSYSCALL_ADDR
#undef VSYSCALL_PHYS_ADDR
#undef VSYSCALL_VIRT_ADDR
#undef VLOAD_OFFSET
#undef VLOAD
#undef VVIRT_OFFSET
#undef VVIRT
#endif /* CONFIG_X86_64 */
/* init_task */
. = ALIGN(THREAD_SIZE);
.data.init_task : AT(ADDR(.data.init_task) - LOAD_OFFSET) {
*(.data.init_task)
}
#ifdef CONFIG_X86_64
:data.init
#endif
/*
* smp_locks might be freed after init
* start/end must be page aligned
*/
. = ALIGN(PAGE_SIZE);
.smp_locks : AT(ADDR(.smp_locks) - LOAD_OFFSET) {
__smp_locks = .;
*(.smp_locks)
__smp_locks_end = .;
. = ALIGN(PAGE_SIZE);
}
/* Init code and data - will be freed after init */
. = ALIGN(PAGE_SIZE);
.init.text : AT(ADDR(.init.text) - LOAD_OFFSET) {
__init_begin = .; /* paired with __init_end */
_sinittext = .;
INIT_TEXT
_einittext = .;
}
.init.data : AT(ADDR(.init.data) - LOAD_OFFSET) {
INIT_DATA
}
. = ALIGN(16);
.init.setup : AT(ADDR(.init.setup) - LOAD_OFFSET) {
__setup_start = .;
*(.init.setup)
__setup_end = .;
}
.initcall.init : AT(ADDR(.initcall.init) - LOAD_OFFSET) {
__initcall_start = .;
INITCALLS
__initcall_end = .;
}
.con_initcall.init : AT(ADDR(.con_initcall.init) - LOAD_OFFSET) {
__con_initcall_start = .;
*(.con_initcall.init)
__con_initcall_end = .;
}
.x86_cpu_dev.init : AT(ADDR(.x86_cpu_dev.init) - LOAD_OFFSET) {
__x86_cpu_dev_start = .;
*(.x86_cpu_dev.init)
__x86_cpu_dev_end = .;
}
SECURITY_INIT
. = ALIGN(8);
.parainstructions : AT(ADDR(.parainstructions) - LOAD_OFFSET) {
__parainstructions = .;
*(.parainstructions)
__parainstructions_end = .;
}
. = ALIGN(8);
.altinstructions : AT(ADDR(.altinstructions) - LOAD_OFFSET) {
__alt_instructions = .;
*(.altinstructions)
__alt_instructions_end = .;
}
.altinstr_replacement : AT(ADDR(.altinstr_replacement) - LOAD_OFFSET) {
*(.altinstr_replacement)
}
/*
* .exit.text is discard at runtime, not link time, to deal with
* references from .altinstructions and .eh_frame
*/
.exit.text : AT(ADDR(.exit.text) - LOAD_OFFSET) {
EXIT_TEXT
}
.exit.data : AT(ADDR(.exit.data) - LOAD_OFFSET) {
EXIT_DATA
}
#ifdef CONFIG_BLK_DEV_INITRD
. = ALIGN(PAGE_SIZE);
.init.ramfs : AT(ADDR(.init.ramfs) - LOAD_OFFSET) {
__initramfs_start = .;
*(.init.ramfs)
__initramfs_end = .;
}
#endif
#if defined(CONFIG_X86_64) && defined(CONFIG_SMP)
/*
* percpu offsets are zero-based on SMP. PERCPU_VADDR() changes the
* output PHDR, so the next output section - __data_nosave - should
* start another section data.init2. Also, pda should be at the head of
* percpu area. Preallocate it and define the percpu offset symbol
* so that it can be accessed as a percpu variable.
*/
. = ALIGN(PAGE_SIZE);
PERCPU_VADDR(0, :percpu)
#else
PERCPU(PAGE_SIZE)
#endif
. = ALIGN(PAGE_SIZE);
/* freed after init ends here */
.init.end : AT(ADDR(.init.end) - LOAD_OFFSET) {
__init_end = .;
}
#ifdef CONFIG_X86_64
.data_nosave : AT(ADDR(.data_nosave) - LOAD_OFFSET) {
. = ALIGN(PAGE_SIZE);
__nosave_begin = .;
*(.data.nosave)
. = ALIGN(PAGE_SIZE);
__nosave_end = .;
} :data.init2
/* use another section data.init2, see PERCPU_VADDR() above */
#endif
/* BSS */
. = ALIGN(PAGE_SIZE);
.bss : AT(ADDR(.bss) - LOAD_OFFSET) {
__bss_start = .;
*(.bss.page_aligned)
*(.bss)
. = ALIGN(4);
__bss_stop = .;
}
. = ALIGN(PAGE_SIZE);
.brk : AT(ADDR(.brk) - LOAD_OFFSET) {
__brk_base = .;
. += 64 * 1024; /* 64k alignment slop space */
*(.brk_reservation) /* areas brk users have reserved */
__brk_limit = .;
}
.end : AT(ADDR(.end) - LOAD_OFFSET) {
_end = .;
}
STABS_DEBUG
DWARF_DEBUG
/* Sections to be discarded */
DISCARDS
/DISCARD/ : { *(.eh_frame) }
}
#ifdef CONFIG_X86_32
ASSERT((_end - LOAD_OFFSET <= KERNEL_IMAGE_SIZE),
"kernel image bigger than KERNEL_IMAGE_SIZE")
#else
/*
* Per-cpu symbols which need to be offset from __per_cpu_load
* for the boot processor.
*/
#define INIT_PER_CPU(x) init_per_cpu__##x = per_cpu__##x + __per_cpu_load
INIT_PER_CPU(gdt_page);
INIT_PER_CPU(irq_stack_union);
/*
* Build-time check on the image size:
*/
ASSERT((_end - _text <= KERNEL_IMAGE_SIZE),
"kernel image bigger than KERNEL_IMAGE_SIZE")
#ifdef CONFIG_SMP
ASSERT((per_cpu__irq_stack_union == 0),
"irq_stack_union is not at start of per-cpu area");
#endif
#endif /* CONFIG_X86_32 */
#ifdef CONFIG_KEXEC
#include <asm/kexec.h>
ASSERT(kexec_control_code_size <= KEXEC_CONTROL_CODE_MAX_SIZE,
"kexec control code size is too big")
#endif