From 1713ce7c43755fe8b0f31ea317513129bf784909 Mon Sep 17 00:00:00 2001 From: Nathan Lynch Date: Wed, 25 Mar 2015 19:13:16 +0100 Subject: [PATCH] ARM: 8329/1: miscellaneous vdso infrastructure, preparation Define the layout of the data structure shared between kernel and userspace. Track the vdso address in the mm_context; needed for communicating AT_SYSINFO_EHDR to the ELF loader. Add declarations for arm_install_vdso; implementation is in a following patch. Define AT_SYSINFO_EHDR, and, if CONFIG_VDSO=y, report the vdso shared object address via the ELF auxiliary vector. Note - this adds the AT_SYSINFO_EHDR in a new user-visible header asm/auxvec.h; this is consistent with other architectures. Signed-off-by: Nathan Lynch Signed-off-by: Russell King --- arch/arm/include/asm/Kbuild | 1 - arch/arm/include/asm/auxvec.h | 1 + arch/arm/include/asm/elf.h | 9 +++++ arch/arm/include/asm/mmu.h | 3 ++ arch/arm/include/asm/vdso.h | 32 +++++++++++++++ arch/arm/include/asm/vdso_datapage.h | 60 ++++++++++++++++++++++++++++ arch/arm/include/uapi/asm/Kbuild | 1 + arch/arm/include/uapi/asm/auxvec.h | 7 ++++ 8 files changed, 113 insertions(+), 1 deletion(-) create mode 100644 arch/arm/include/asm/auxvec.h create mode 100644 arch/arm/include/asm/vdso.h create mode 100644 arch/arm/include/asm/vdso_datapage.h create mode 100644 arch/arm/include/uapi/asm/auxvec.h diff --git a/arch/arm/include/asm/Kbuild b/arch/arm/include/asm/Kbuild index fe74c0d1e485..eb0f43f3e3f1 100644 --- a/arch/arm/include/asm/Kbuild +++ b/arch/arm/include/asm/Kbuild @@ -1,6 +1,5 @@ -generic-y += auxvec.h generic-y += bitsperlong.h generic-y += cputime.h generic-y += current.h diff --git a/arch/arm/include/asm/auxvec.h b/arch/arm/include/asm/auxvec.h new file mode 100644 index 000000000000..fbd388c46299 --- /dev/null +++ b/arch/arm/include/asm/auxvec.h @@ -0,0 +1 @@ +#include diff --git a/arch/arm/include/asm/elf.h b/arch/arm/include/asm/elf.h index afb9cafd3786..ac3f17fb4c8d 100644 --- a/arch/arm/include/asm/elf.h +++ b/arch/arm/include/asm/elf.h @@ -1,7 +1,9 @@ #ifndef __ASMARM_ELF_H #define __ASMARM_ELF_H +#include #include +#include /* * ELF register definitions.. @@ -130,6 +132,13 @@ extern unsigned long arch_randomize_brk(struct mm_struct *mm); #define arch_randomize_brk arch_randomize_brk #ifdef CONFIG_MMU +#ifdef CONFIG_VDSO +#define ARCH_DLINFO \ +do { \ + NEW_AUX_ENT(AT_SYSINFO_EHDR, \ + (elf_addr_t)current->mm->context.vdso); \ +} while (0) +#endif #define ARCH_HAS_SETUP_ADDITIONAL_PAGES 1 struct linux_binprm; int arch_setup_additional_pages(struct linux_binprm *, int); diff --git a/arch/arm/include/asm/mmu.h b/arch/arm/include/asm/mmu.h index 64fd15159b7d..a5b47421059d 100644 --- a/arch/arm/include/asm/mmu.h +++ b/arch/arm/include/asm/mmu.h @@ -11,6 +11,9 @@ typedef struct { #endif unsigned int vmalloc_seq; unsigned long sigpage; +#ifdef CONFIG_VDSO + unsigned long vdso; +#endif } mm_context_t; #ifdef CONFIG_CPU_HAS_ASID diff --git a/arch/arm/include/asm/vdso.h b/arch/arm/include/asm/vdso.h new file mode 100644 index 000000000000..d0295f1dd1a3 --- /dev/null +++ b/arch/arm/include/asm/vdso.h @@ -0,0 +1,32 @@ +#ifndef __ASM_VDSO_H +#define __ASM_VDSO_H + +#ifdef __KERNEL__ + +#ifndef __ASSEMBLY__ + +struct mm_struct; + +#ifdef CONFIG_VDSO + +void arm_install_vdso(struct mm_struct *mm, unsigned long addr); + +extern char vdso_start, vdso_end; + +extern unsigned int vdso_total_pages; + +#else /* CONFIG_VDSO */ + +static inline void arm_install_vdso(struct mm_struct *mm, unsigned long addr) +{ +} + +#define vdso_total_pages 0 + +#endif /* CONFIG_VDSO */ + +#endif /* __ASSEMBLY__ */ + +#endif /* __KERNEL__ */ + +#endif /* __ASM_VDSO_H */ diff --git a/arch/arm/include/asm/vdso_datapage.h b/arch/arm/include/asm/vdso_datapage.h new file mode 100644 index 000000000000..9be259442fca --- /dev/null +++ b/arch/arm/include/asm/vdso_datapage.h @@ -0,0 +1,60 @@ +/* + * Adapted from arm64 version. + * + * Copyright (C) 2012 ARM Limited + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see . + */ +#ifndef __ASM_VDSO_DATAPAGE_H +#define __ASM_VDSO_DATAPAGE_H + +#ifdef __KERNEL__ + +#ifndef __ASSEMBLY__ + +#include + +/* Try to be cache-friendly on systems that don't implement the + * generic timer: fit the unconditionally updated fields in the first + * 32 bytes. + */ +struct vdso_data { + u32 seq_count; /* sequence count - odd during updates */ + u16 tk_is_cntvct; /* fall back to syscall if false */ + u16 cs_shift; /* clocksource shift */ + u32 xtime_coarse_sec; /* coarse time */ + u32 xtime_coarse_nsec; + + u32 wtm_clock_sec; /* wall to monotonic offset */ + u32 wtm_clock_nsec; + u32 xtime_clock_sec; /* CLOCK_REALTIME - seconds */ + u32 cs_mult; /* clocksource multiplier */ + + u64 cs_cycle_last; /* last cycle value */ + u64 cs_mask; /* clocksource mask */ + + u64 xtime_clock_snsec; /* CLOCK_REALTIME sub-ns base */ + u32 tz_minuteswest; /* timezone info for gettimeofday(2) */ + u32 tz_dsttime; +}; + +union vdso_data_store { + struct vdso_data data; + u8 page[PAGE_SIZE]; +}; + +#endif /* !__ASSEMBLY__ */ + +#endif /* __KERNEL__ */ + +#endif /* __ASM_VDSO_DATAPAGE_H */ diff --git a/arch/arm/include/uapi/asm/Kbuild b/arch/arm/include/uapi/asm/Kbuild index 70a1c9da30ca..a1c05f93d920 100644 --- a/arch/arm/include/uapi/asm/Kbuild +++ b/arch/arm/include/uapi/asm/Kbuild @@ -1,6 +1,7 @@ # UAPI Header export list include include/uapi/asm-generic/Kbuild.asm +header-y += auxvec.h header-y += byteorder.h header-y += fcntl.h header-y += hwcap.h diff --git a/arch/arm/include/uapi/asm/auxvec.h b/arch/arm/include/uapi/asm/auxvec.h new file mode 100644 index 000000000000..cb02a767a500 --- /dev/null +++ b/arch/arm/include/uapi/asm/auxvec.h @@ -0,0 +1,7 @@ +#ifndef __ASM_AUXVEC_H +#define __ASM_AUXVEC_H + +/* VDSO location */ +#define AT_SYSINFO_EHDR 33 + +#endif -- 2.39.5