From: "Luis R. Rodriguez" <mcg...@kernel.org> Section ranges are on one of the types of custom sections types used in Linux. This provides a series of helpers for defining them and using them. Most importantly this also enables us to avoid modifying the linker script when we add a new section range.
It turns out a lot of custom sections are actually section ranges, and these are typically spelled out in their architecture specific asm/sections.h file -- we anable architectures to override what asm is used for section ranges but start by default trusting the asm-generic version all around. v4: o tons of documentation love o fix arch/x86/tools/relocs.c typo - which caused compilation issues on old toolchains o port to new shiny sphinx documentation o sprinkle a few more needed VMLINUX_SYMBOL() - fixes compilation on blackfin o name changes as suggested by Boris: - %s/SECTION_TYPE_RANGES/rng/g - %s/SECTION_TYPE/SECTION_CORE/g - %s/section_type_asmtype/section_core_type/g - %s/section_type/section_core/g - %s/section_rng/set_section_rng/g - rebrand DECLARE_SECTION_RNG() as DEFINE_SECTION_RANGE() - this is the asm version of the respective C version, this will have a userspace C demo added later. o move __LINUX_RANGE() and __LINUX_RANGE_ORDER() - fixes builds on sparc o adds section ranges to linker script o rename SECTION_RANGE_ALL() o use default alignment, fixes builds on powerpc and arm for both __LINUX_RANGE() and __LINUX_RANGE_ORDER() o expand documentation to document modules support o add maintainers o use generic-y v3: new in this series, uses copyleft-next Signed-off-by: Luis R. Rodriguez <mcg...@kernel.org> --- Documentation/sections/index.rst | 1 + Documentation/sections/ranges.rst | 49 ++++++++++++++ MAINTAINERS | 10 +++ arch/alpha/include/asm/Kbuild | 1 + arch/arc/include/asm/Kbuild | 1 + arch/arm/include/asm/Kbuild | 1 + arch/arm64/include/asm/Kbuild | 1 + arch/avr32/include/asm/Kbuild | 1 + arch/blackfin/include/asm/Kbuild | 1 + arch/c6x/include/asm/Kbuild | 1 + arch/cris/include/asm/Kbuild | 1 + arch/frv/include/asm/Kbuild | 1 + arch/h8300/include/asm/Kbuild | 1 + arch/hexagon/include/asm/Kbuild | 1 + arch/ia64/include/asm/Kbuild | 1 + arch/m32r/include/asm/Kbuild | 1 + arch/m68k/include/asm/Kbuild | 1 + arch/metag/include/asm/Kbuild | 1 + arch/microblaze/include/asm/Kbuild | 1 + arch/mips/include/asm/Kbuild | 1 + arch/mn10300/include/asm/Kbuild | 1 + arch/nios2/include/asm/Kbuild | 1 + arch/openrisc/include/asm/Kbuild | 1 + arch/parisc/include/asm/Kbuild | 1 + arch/powerpc/include/asm/Kbuild | 1 + arch/s390/include/asm/Kbuild | 1 + arch/score/include/asm/Kbuild | 1 + arch/sh/include/asm/Kbuild | 1 + arch/sparc/include/asm/Kbuild | 1 + arch/tile/include/asm/Kbuild | 1 + arch/um/include/asm/Kbuild | 1 + arch/unicore32/include/asm/Kbuild | 1 + arch/x86/include/asm/Kbuild | 1 + arch/x86/tools/relocs.c | 2 + arch/xtensa/include/asm/Kbuild | 1 + include/asm-generic/ranges.h | 89 ++++++++++++++++++++++++++ include/asm-generic/vmlinux.lds.h | 12 +++- include/linux/ranges.h | 128 +++++++++++++++++++++++++++++++++++++ 38 files changed, 320 insertions(+), 2 deletions(-) create mode 100644 Documentation/sections/ranges.rst create mode 100644 include/asm-generic/ranges.h create mode 100644 include/linux/ranges.h diff --git a/Documentation/sections/index.rst b/Documentation/sections/index.rst index d411e9b22eb3..6dd93ddd5dbe 100644 --- a/Documentation/sections/index.rst +++ b/Documentation/sections/index.rst @@ -9,3 +9,4 @@ used throughout the kernel to help declare and define them. :maxdepth: 4 section-core + ranges diff --git a/Documentation/sections/ranges.rst b/Documentation/sections/ranges.rst new file mode 100644 index 000000000000..1293dcb3ab38 --- /dev/null +++ b/Documentation/sections/ranges.rst @@ -0,0 +1,49 @@ +==================== +Linux section ranges +==================== + +This documents Linux' use of section ranges, how you can use +them and how they work. + +About section ranges +==================== + +Introduction +------------ +.. kernel-doc:: include/linux/ranges.h + :doc: Introduction + +Section range module support +---------------------------- +.. kernel-doc:: include/linux/ranges.h + :doc: Section range module support + +Section range helpers +===================== +.. kernel-doc:: include/linux/ranges.h + :doc: Section range helpers + +DECLARE_SECTION_RANGE +--------------------- +.. kernel-doc:: include/linux/ranges.h + :functions: DECLARE_SECTION_RANGE + +DEFINE_SECTION_RANGE +-------------------- +.. kernel-doc:: include/linux/ranges.h + :functions: DEFINE_SECTION_RANGE + +SECTION_ADDR_IN_RANGE +--------------------- +.. kernel-doc:: include/linux/ranges.h + :functions: SECTION_ADDR_IN_RANGE + +__LINUX_RANGE +------------- +.. kernel-doc:: include/asm-generic/ranges.h + :functions: __LINUX_RANGE + +__LINUX_RANGE_ORDER +------------------- +.. kernel-doc:: include/asm-generic/ranges.h + :functions: __LINUX_RANGE_ORDER diff --git a/MAINTAINERS b/MAINTAINERS index 689c12075842..1a217751aa8a 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -5217,6 +5217,16 @@ S: Supported F: drivers/base/power/domain*.c F: include/linux/pm_domain.h +GENERIC SECTION RANGES +M: "Luis R. Rodriguez" <mcg...@kernel.org> +M: "H. Peter Anvin" <h...@zytor.com> +L: linux-a...@vger.kernel.org +L: linux-ker...@vger.kernel.org +S: Supported +F: include/asm-generic/ranges.h +F: include/linux/ranges.h +F: Documentation/sections/ranges.rst + GENERIC SECTIONS M: "Luis R. Rodriguez" <mcg...@kernel.org> M: Josh Poimboeuf <jpoim...@redhat.com> diff --git a/arch/alpha/include/asm/Kbuild b/arch/alpha/include/asm/Kbuild index 5422827f1585..e44c896b91c4 100644 --- a/arch/alpha/include/asm/Kbuild +++ b/arch/alpha/include/asm/Kbuild @@ -11,3 +11,4 @@ generic-y += preempt.h generic-y += sections.h generic-y += trace_clock.h generic-y += section-core.h +generic-y += ranges.h diff --git a/arch/arc/include/asm/Kbuild b/arch/arc/include/asm/Kbuild index 9a0929576de1..e5295413fdf8 100644 --- a/arch/arc/include/asm/Kbuild +++ b/arch/arc/include/asm/Kbuild @@ -51,3 +51,4 @@ generic-y += vga.h generic-y += word-at-a-time.h generic-y += xor.h generic-y += section-core.h +generic-y += ranges.h diff --git a/arch/arm/include/asm/Kbuild b/arch/arm/include/asm/Kbuild index 47923635be16..8e52300e1eed 100644 --- a/arch/arm/include/asm/Kbuild +++ b/arch/arm/include/asm/Kbuild @@ -40,3 +40,4 @@ generic-y += timex.h generic-y += trace_clock.h generic-y += unaligned.h generic-y += section-core.h +generic-y += ranges.h diff --git a/arch/arm64/include/asm/Kbuild b/arch/arm64/include/asm/Kbuild index 42d00806e4fb..5ff184574976 100644 --- a/arch/arm64/include/asm/Kbuild +++ b/arch/arm64/include/asm/Kbuild @@ -53,3 +53,4 @@ generic-y += user.h generic-y += vga.h generic-y += xor.h generic-y += section-core.h +generic-y += ranges.h diff --git a/arch/avr32/include/asm/Kbuild b/arch/avr32/include/asm/Kbuild index f2c3b656a0e7..edc176348d7c 100644 --- a/arch/avr32/include/asm/Kbuild +++ b/arch/avr32/include/asm/Kbuild @@ -23,3 +23,4 @@ generic-y += vga.h generic-y += word-at-a-time.h generic-y += xor.h generic-y += section-core.h +generic-y += ranges.h diff --git a/arch/blackfin/include/asm/Kbuild b/arch/blackfin/include/asm/Kbuild index 7de674411bed..35b7752e65c0 100644 --- a/arch/blackfin/include/asm/Kbuild +++ b/arch/blackfin/include/asm/Kbuild @@ -49,3 +49,4 @@ generic-y += user.h generic-y += word-at-a-time.h generic-y += xor.h generic-y += section-core.h +generic-y += ranges.h diff --git a/arch/c6x/include/asm/Kbuild b/arch/c6x/include/asm/Kbuild index 38127ce747be..cede2a950fbf 100644 --- a/arch/c6x/include/asm/Kbuild +++ b/arch/c6x/include/asm/Kbuild @@ -63,3 +63,4 @@ generic-y += vga.h generic-y += word-at-a-time.h generic-y += xor.h generic-y += section-core.h +generic-y += ranges.h diff --git a/arch/cris/include/asm/Kbuild b/arch/cris/include/asm/Kbuild index 385cd88a9d9e..fb8bb4112773 100644 --- a/arch/cris/include/asm/Kbuild +++ b/arch/cris/include/asm/Kbuild @@ -46,3 +46,4 @@ generic-y += vga.h generic-y += word-at-a-time.h generic-y += xor.h generic-y += section-core.h +generic-y += ranges.h diff --git a/arch/frv/include/asm/Kbuild b/arch/frv/include/asm/Kbuild index 46d7c599d9b8..5191fec655d7 100644 --- a/arch/frv/include/asm/Kbuild +++ b/arch/frv/include/asm/Kbuild @@ -9,3 +9,4 @@ generic-y += preempt.h generic-y += trace_clock.h generic-y += word-at-a-time.h generic-y += section-core.h +generic-y += ranges.h diff --git a/arch/h8300/include/asm/Kbuild b/arch/h8300/include/asm/Kbuild index 1ec04ec1c82b..7929a992566c 100644 --- a/arch/h8300/include/asm/Kbuild +++ b/arch/h8300/include/asm/Kbuild @@ -76,3 +76,4 @@ generic-y += vga.h generic-y += word-at-a-time.h generic-y += xor.h generic-y += section-core.h +generic-y += ranges.h diff --git a/arch/hexagon/include/asm/Kbuild b/arch/hexagon/include/asm/Kbuild index 37d7bfae7619..af17ee334788 100644 --- a/arch/hexagon/include/asm/Kbuild +++ b/arch/hexagon/include/asm/Kbuild @@ -61,3 +61,4 @@ generic-y += vga.h generic-y += word-at-a-time.h generic-y += xor.h generic-y += section-core.h +generic-y += ranges.h diff --git a/arch/ia64/include/asm/Kbuild b/arch/ia64/include/asm/Kbuild index 672c6d5da18c..d8f226b35a0a 100644 --- a/arch/ia64/include/asm/Kbuild +++ b/arch/ia64/include/asm/Kbuild @@ -10,3 +10,4 @@ generic-y += trace_clock.h generic-y += vtime.h generic-y += word-at-a-time.h generic-y += section-core.h +generic-y += ranges.h diff --git a/arch/m32r/include/asm/Kbuild b/arch/m32r/include/asm/Kbuild index 6111e1523750..1c6504d29312 100644 --- a/arch/m32r/include/asm/Kbuild +++ b/arch/m32r/include/asm/Kbuild @@ -12,3 +12,4 @@ generic-y += sections.h generic-y += trace_clock.h generic-y += word-at-a-time.h generic-y += section-core.h +generic-y += ranges.h diff --git a/arch/m68k/include/asm/Kbuild b/arch/m68k/include/asm/Kbuild index eef72c464c9b..d465f51c2088 100644 --- a/arch/m68k/include/asm/Kbuild +++ b/arch/m68k/include/asm/Kbuild @@ -36,3 +36,4 @@ generic-y += types.h generic-y += word-at-a-time.h generic-y += xor.h generic-y += section-core.h +generic-y += ranges.h diff --git a/arch/metag/include/asm/Kbuild b/arch/metag/include/asm/Kbuild index 50ebd5a30d16..c869b1ebd583 100644 --- a/arch/metag/include/asm/Kbuild +++ b/arch/metag/include/asm/Kbuild @@ -57,3 +57,4 @@ generic-y += vga.h generic-y += word-at-a-time.h generic-y += xor.h generic-y += section-core.h +generic-y += ranges.h diff --git a/arch/microblaze/include/asm/Kbuild b/arch/microblaze/include/asm/Kbuild index c6c2cf6edc98..63c083a1f8da 100644 --- a/arch/microblaze/include/asm/Kbuild +++ b/arch/microblaze/include/asm/Kbuild @@ -12,3 +12,4 @@ generic-y += syscalls.h generic-y += trace_clock.h generic-y += word-at-a-time.h generic-y += section-core.h +generic-y += ranges.h diff --git a/arch/mips/include/asm/Kbuild b/arch/mips/include/asm/Kbuild index 12f7c5984c03..ed225600c8a4 100644 --- a/arch/mips/include/asm/Kbuild +++ b/arch/mips/include/asm/Kbuild @@ -21,3 +21,4 @@ generic-y += user.h generic-y += word-at-a-time.h generic-y += xor.h generic-y += section-core.h +generic-y += ranges.h diff --git a/arch/mn10300/include/asm/Kbuild b/arch/mn10300/include/asm/Kbuild index f8145bc85835..656af7b69940 100644 --- a/arch/mn10300/include/asm/Kbuild +++ b/arch/mn10300/include/asm/Kbuild @@ -11,3 +11,4 @@ generic-y += sections.h generic-y += trace_clock.h generic-y += word-at-a-time.h generic-y += section-core.h +generic-y += ranges.h diff --git a/arch/nios2/include/asm/Kbuild b/arch/nios2/include/asm/Kbuild index c9c7cb82b00f..c55880659d67 100644 --- a/arch/nios2/include/asm/Kbuild +++ b/arch/nios2/include/asm/Kbuild @@ -64,3 +64,4 @@ generic-y += vga.h generic-y += word-at-a-time.h generic-y += xor.h generic-y += section-core.h +generic-y += ranges.h diff --git a/arch/openrisc/include/asm/Kbuild b/arch/openrisc/include/asm/Kbuild index 86175e701869..7d6a704b808c 100644 --- a/arch/openrisc/include/asm/Kbuild +++ b/arch/openrisc/include/asm/Kbuild @@ -72,3 +72,4 @@ generic-y += vga.h generic-y += word-at-a-time.h generic-y += xor.h generic-y += section-core.h +generic-y += ranges.h diff --git a/arch/parisc/include/asm/Kbuild b/arch/parisc/include/asm/Kbuild index 6f43f33f0e0f..1a263a7158e2 100644 --- a/arch/parisc/include/asm/Kbuild +++ b/arch/parisc/include/asm/Kbuild @@ -30,3 +30,4 @@ generic-y += vga.h generic-y += word-at-a-time.h generic-y += xor.h generic-y += section-core.h +generic-y += ranges.h diff --git a/arch/powerpc/include/asm/Kbuild b/arch/powerpc/include/asm/Kbuild index b49fab7bab2f..065c6e84fb67 100644 --- a/arch/powerpc/include/asm/Kbuild +++ b/arch/powerpc/include/asm/Kbuild @@ -8,3 +8,4 @@ generic-y += preempt.h generic-y += rwsem.h generic-y += vtime.h generic-y += section-core.h +generic-y += ranges.h diff --git a/arch/s390/include/asm/Kbuild b/arch/s390/include/asm/Kbuild index 89e74b59f32d..3e8b95927cb5 100644 --- a/arch/s390/include/asm/Kbuild +++ b/arch/s390/include/asm/Kbuild @@ -9,3 +9,4 @@ generic-y += preempt.h generic-y += trace_clock.h generic-y += word-at-a-time.h generic-y += section-core.h +generic-y += ranges.h diff --git a/arch/score/include/asm/Kbuild b/arch/score/include/asm/Kbuild index f089a264cd38..f0cdb2cbca4d 100644 --- a/arch/score/include/asm/Kbuild +++ b/arch/score/include/asm/Kbuild @@ -15,3 +15,4 @@ generic-y += xor.h generic-y += serial.h generic-y += word-at-a-time.h generic-y += section-core.h +generic-y += ranges.h diff --git a/arch/sh/include/asm/Kbuild b/arch/sh/include/asm/Kbuild index 7b0356dca562..c9bb7932a3d1 100644 --- a/arch/sh/include/asm/Kbuild +++ b/arch/sh/include/asm/Kbuild @@ -40,3 +40,4 @@ generic-y += trace_clock.h generic-y += ucontext.h generic-y += xor.h generic-y += section-core.h +generic-y += ranges.h diff --git a/arch/sparc/include/asm/Kbuild b/arch/sparc/include/asm/Kbuild index d51b84d6b4b7..79664d10e63b 100644 --- a/arch/sparc/include/asm/Kbuild +++ b/arch/sparc/include/asm/Kbuild @@ -23,3 +23,4 @@ generic-y += trace_clock.h generic-y += types.h generic-y += word-at-a-time.h generic-y += section-core.h +generic-y += ranges.h diff --git a/arch/tile/include/asm/Kbuild b/arch/tile/include/asm/Kbuild index 7b8a652e43ae..951fa4be571d 100644 --- a/arch/tile/include/asm/Kbuild +++ b/arch/tile/include/asm/Kbuild @@ -42,3 +42,4 @@ generic-y += trace_clock.h generic-y += types.h generic-y += xor.h generic-y += section-core.h +generic-y += ranges.h diff --git a/arch/um/include/asm/Kbuild b/arch/um/include/asm/Kbuild index e9849834d55e..99be54949b99 100644 --- a/arch/um/include/asm/Kbuild +++ b/arch/um/include/asm/Kbuild @@ -28,3 +28,4 @@ generic-y += trace_clock.h generic-y += word-at-a-time.h generic-y += xor.h generic-y += section-core.h +generic-y += ranges.h diff --git a/arch/unicore32/include/asm/Kbuild b/arch/unicore32/include/asm/Kbuild index 256c45b3ae34..6c35905fe371 100644 --- a/arch/unicore32/include/asm/Kbuild +++ b/arch/unicore32/include/asm/Kbuild @@ -64,3 +64,4 @@ generic-y += user.h generic-y += vga.h generic-y += word-at-a-time.h generic-y += xor.h +generic-y += ranges.h diff --git a/arch/x86/include/asm/Kbuild b/arch/x86/include/asm/Kbuild index f6914a57bc16..f790756fdb48 100644 --- a/arch/x86/include/asm/Kbuild +++ b/arch/x86/include/asm/Kbuild @@ -17,3 +17,4 @@ generic-y += early_ioremap.h generic-y += mcs_spinlock.h generic-y += mm-arch-hooks.h generic-y += section-core.h +generic-y += ranges.h diff --git a/arch/x86/tools/relocs.c b/arch/x86/tools/relocs.c index 0c2fae8d929d..c215db049920 100644 --- a/arch/x86/tools/relocs.c +++ b/arch/x86/tools/relocs.c @@ -68,6 +68,8 @@ static const char * const sym_regex_kernel[S_NSYMTYPES] = { "__end_rodata|" "__initramfs_start|" "(jiffies|jiffies_64)|" + ".rodata.rng.*|" + ".init.text.rng.*|" #if ELF_BITS == 64 "__per_cpu_load|" "init_per_cpu__.*|" diff --git a/arch/xtensa/include/asm/Kbuild b/arch/xtensa/include/asm/Kbuild index 81ca6816bd72..221b6b652500 100644 --- a/arch/xtensa/include/asm/Kbuild +++ b/arch/xtensa/include/asm/Kbuild @@ -32,3 +32,4 @@ generic-y += trace_clock.h generic-y += word-at-a-time.h generic-y += xor.h generic-y += section-core.h +generic-y += ranges.h diff --git a/include/asm-generic/ranges.h b/include/asm-generic/ranges.h new file mode 100644 index 000000000000..74cd941aa2f8 --- /dev/null +++ b/include/asm-generic/ranges.h @@ -0,0 +1,89 @@ +#ifndef _ASM_GENERIC_RANGES_H_ +#define _ASM_GENERIC_RANGES_H_ +/* + * Copyright (C) 2016 Luis R. Rodriguez <mcg...@kernel.org> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of copyleft-next (version 0.3.1 or later) as published + * at http://copyleft-next.org/. + */ +#include <asm/section-core.h> + +#define SECTION_RNG(section, name) \ + SECTION_CORE(section, rng, name, \ + SECTION_ORDER_ANY) + +#define SECTION_RNG_LEVEL(section, name, level) \ + SECTION_CORE(section, rng, name, level) + +#define SECTION_RNG_ALL(section) \ + SECTION_CORE_ALL(section,rng) + +#ifndef set_section_rng +# define set_section_rng(section, name, flags) \ + set_section_core(section, rng, name, \ + SECTION_ORDER_ANY, flags) +#endif + +#ifndef set_section_rng_type +# define set_section_rng_type(section, name, flags, type) \ + set_section_core_type(section, rng, name, \ + SECTION_ORDER_ANY, flags, type) +#endif + +#ifndef set_section_rng_level +# define set_section_rng_level(section, name, level, flags) \ + set_section_core(section, rng, name, level, flags) +#endif + +#ifndef push_section_rng +# define push_section_rng(section, name, flags) \ + push_section_core(section, rng, name, \ + SECTION_ORDER_ANY, flags) +#endif + +#ifndef push_section_rng_level +# define push_section_rng_level(section, name, level, flags) \ + push_section_core(section, rng, name, \ + level, flags) +#endif + +#ifndef __ASSEMBLY__ +/** + * __LINUX_RANGE - short hand association into a section range + * + * @section: ELF section name to place section range into + * @name: section range name + * + * This helper can be used by subsystems to define their own subsystem + * specific helpers to easily associate a piece of code being defined to a + * section range. + */ +#define __LINUX_RANGE(section, name) \ + __attribute__((__section__(SECTION_RNG(section, name)))) + +/** + * __LINUX_RANGE_ORDER - short hand association into a section range of order + * + * @section: ELF section name to place section range into + * @name: section range name + * @level: order level, a number. The order level gets tucked into the + * section as a postfix string. Order levels are sorted using + * binutils SORT(), the number is sorted as a string, as such be + * sure to fill with zeroes any empty digits. For instance if you are + * using 3 levels of digits for order levels, use 001 for the first entry, + * 0002 for the second, 999 for the last entry. You can use however many + * digits you need. + * + * This helper can be used by subsystems to define their own subsystem specific + * helpers to easily associate a piece of code being defined to a section range + * with an associated specific order level. The order level provides the + * ability for explicit user ordering of code. Sorting takes place at link + * time, after compilation. + */ +#define __LINUX_RANGE_ORDER(section, name, level) \ + __attribute__((__section__(SECTION_RNG_LEVEL(section, name, level)))) + +#endif /* __ASSEMBLY__ */ + +#endif /* _ASM_GENERIC_RANGES_H_ */ diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index 731087276a32..ad843555e6a4 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -56,6 +56,7 @@ #include <linux/export.h> #include <asm/section-core.h> +#include <asm/ranges.h> /* Align . to a 8 byte boundary equals to maximum function alignment. */ #define ALIGN_FUNCTION() . = ALIGN(8) @@ -200,6 +201,7 @@ /* .data section */ #define DATA_DATA \ *(SECTION_DATA) \ + *(SORT(SECTION_RNG_ALL(SECTION_DATA))) \ *(SECTION_REF_DATA) \ *(.data..shared_aligned) /* percpu related */ \ MEM_KEEP(init.data) \ @@ -265,7 +267,9 @@ . = ALIGN((align)); \ SECTION_RODATA : AT(ADDR(SECTION_RODATA) - LOAD_OFFSET) { \ VMLINUX_SYMBOL(__start_rodata) = .; \ - *(SECTION_RODATA) *(SECTION_ALL(SECTION_RODATA)) \ + *(SECTION_RODATA) \ + *(SORT(SECTION_RNG_ALL(SECTION_RODATA))) \ + *(SECTION_ALL(SECTION_RODATA)) \ RO_AFTER_INIT_DATA /* Read only after init */ \ *(__vermagic) /* Kernel version magic */ \ . = ALIGN(8); \ @@ -433,7 +437,9 @@ * during second ld run in second ld pass when generating System.map */ #define TEXT_TEXT \ ALIGN_FUNCTION(); \ - *(.text.hot SECTION_TEXT .text.fixup .text.unlikely) \ + *(.text.hot SECTION_TEXT) \ + *(SORT(SECTION_RNG_ALL(SECTION_TEXT))) \ + *(.text.fixup .text.unlikely) \ *(SECTION_REF) \ MEM_KEEP(init.text) \ MEM_KEEP(exit.text) \ @@ -529,6 +535,7 @@ /* init and exit section handling */ #define INIT_DATA \ *(SECTION_INIT_DATA) \ + *(SORT(SECTION_RNG_ALL(SECTION_INIT_DATA))) \ MEM_DISCARD(init.data) \ KERNEL_CTORS() \ MCOUNT_REC() \ @@ -551,6 +558,7 @@ #define INIT_TEXT \ *(SECTION_INIT) \ + *(SORT(SECTION_RNG_ALL(SECTION_INIT))) \ *(.text.startup) \ MEM_DISCARD(init.text) diff --git a/include/linux/ranges.h b/include/linux/ranges.h new file mode 100644 index 000000000000..30b2182bd484 --- /dev/null +++ b/include/linux/ranges.h @@ -0,0 +1,128 @@ +#ifndef _LINUX_RANGES_H +#define _LINUX_RANGES_H +/* + * Linux section ranges + * + * Copyright (C) 2016 Luis R. Rodriguez <mcg...@kernel.org> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of copyleft-next (version 0.3.1 or later) as published + * at http://copyleft-next.org/. + */ +#include <linux/sections.h> +#include <asm/ranges.h> + +#ifndef __ASSEMBLY__ + +/** + * DOC: Introduction + * + * A section ranges consists of explicitly annotated series executable code + * stitched together for the purpose of selective placement into standard or + * architecture specific ELF sections. What ELF section is used is utility + * specific. Linux has historically implicitly used section ranges, however + * they were all built in an adhoc manner and typically required linker script + * modifications per architecture. The section range API allows adding new + * bundles of stiched executable code into custom ELF sections by only + * modifying C or asm code in an architecture agnostic form. + * + * This documents the set of helpers available to declare, and define section + * ranges and associate each section range to a specific Linux ELF section. + */ + +/** + * DOC: Section range module support + * + * Modules can use section ranges, however the section range definition must be + * built-in to the kernel. That is, the code that implements + * DEFINE_SECTION_RANGE() must be built-in, and modular code cannot add more + * items in to the section range (with __LINUX_RANGE() or + * __LINUX_RANGE_ORDER()), unless kernel/module.c find_module_sections() and + * module-common.lds.S are updated accordingly with a respective module + * notifier to account for updates. This restriction may be enhanced in the + * future. + */ + +/** + * DOC: Section range helpers + * + * These are helpers for section ranges. + */ + +/** + * DECLARE_SECTION_RANGE - Declares a section range + * + * @name: section range name + * + * Declares a section range to help code access the range. Typically if + * a subsystems needs code to have direct access to the section range the + * subsystem's header file would declare the section range. Care should be + * taken to only declare the section range in a header file if access to it + * is truly needed outside of the code defining it. You typically would + * rather instead provide helpers which access the section range with special + * code on behalf of the caller. + */ +#define DECLARE_SECTION_RANGE(name) \ + DECLARE_LINUX_SECTION_RO(char, name) + +/** + * __SECTION_RANGE_BEGIN - Constructs the beginning of a section range + * + * @name: section range name + * @__section: ELF section to place section range into + * + * Constructs the beginning of a section range. You will typically not need + * to use this directly. + */ +#define __SECTION_RANGE_BEGIN(name, __section) \ + const __typeof__(VMLINUX_SYMBOL(name)[0]) \ + __attribute__((used, \ + weak, \ + __aligned__(LINUX_SECTION_ALIGNMENT(name)),\ + section(SECTION_RNG_LEVEL(__section, name,)))) + +/** + * __SECTION_RANGE_END - Constructs the end of a section range + * + * @name: section range name + * @__section: ELF section to place section range into + * + * Constructs the end of a section range. You will typically not need + * to use this directly. + */ +#define __SECTION_RANGE_END(name, __section) \ + const __typeof__(VMLINUX_SYMBOL(name)[0]) \ + __attribute__((used, \ + __aligned__(LINUX_SECTION_ALIGNMENT(name)),\ + section(SECTION_RNG_LEVEL(__section, name, ~)))) + +/** + * DEFINE_SECTION_RANGE - Defines a section range + * + * @name: section range name + * @section: ELF section name to place section range into + * + * Defines a section range, used for executable code. Section ranges are + * defined in the code that takes ownership and makes use of the section + * range. + */ +#define DEFINE_SECTION_RANGE(name, section) \ + DECLARE_LINUX_SECTION_RO(char, name); \ + __SECTION_RANGE_BEGIN(name, section) VMLINUX_SYMBOL(name)[0] = {};\ + __SECTION_RANGE_END(name, section) VMLINUX_SYMBOL(name##__end)[0] = {} + +/** + * SECTION_ADDR_IN_RANGE - returns true if address is in range + * + * @name: section range name + * @addr: address to query for + * + * Returns true if the address is in the section range. + */ +#define SECTION_ADDR_IN_RANGE(name, addr) \ + (addr >= (unsigned long) LINUX_SECTION_START(name) && \ + addr < (unsigned long) LINUX_SECTION_END(name)) + +#endif /* __ASSEMBLY__ */ + +#endif /* _LINUX_RANGES_H */ -- 2.9.2 _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org https://lists.xen.org/xen-devel