arm64: VDSO support
This patch adds VDSO support for 64-bit applications. The VDSO code is currently used for sys_rt_sigreturn() and optimised gettimeofday() (using the user-accessible generic counter). Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Tony Lindgren <tony@atomide.com> Acked-by: Nicolas Pitre <nico@linaro.org> Acked-by: Olof Johansson <olof@lixom.net> Acked-by: Santosh Shilimkar <santosh.shilimkar@ti.com> Acked-by: Arnd Bergmann <arnd@arndb.de>hifive-unleashed-5.1
Will Deacon
Catalin Marinas
parent
7992d60dc4
commit
9031fefde6
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@ -0,0 +1,41 @@
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/*
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* Copyright (C) 2012 ARM Limited
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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#ifndef __ASM_VDSO_H
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#define __ASM_VDSO_H
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#ifdef __KERNEL__
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/*
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* Default link address for the vDSO.
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* Since we randomise the VDSO mapping, there's little point in trying
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* to prelink this.
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*/
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#define VDSO_LBASE 0x0
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#ifndef __ASSEMBLY__
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#include <generated/vdso-offsets.h>
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#define VDSO_SYMBOL(base, name) \
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({ \
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(void *)(vdso_offset_##name - VDSO_LBASE + (unsigned long)(base)); \
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})
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#endif /* !__ASSEMBLY__ */
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#endif /* __KERNEL__ */
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#endif /* __ASM_VDSO_H */
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@ -0,0 +1,43 @@
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/*
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* Copyright (C) 2012 ARM Limited
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program. If not, see <http://www.gnu.org/licenses/>.
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*/
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#ifndef __ASM_VDSO_DATAPAGE_H
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#define __ASM_VDSO_DATAPAGE_H
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#ifdef __KERNEL__
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#ifndef __ASSEMBLY__
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struct vdso_data {
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__u64 cs_cycle_last; /* Timebase at clocksource init */
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__u64 xtime_clock_sec; /* Kernel time */
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__u64 xtime_clock_nsec;
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__u64 xtime_coarse_sec; /* Coarse time */
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__u64 xtime_coarse_nsec;
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__u64 wtm_clock_sec; /* Wall to monotonic time */
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__u64 wtm_clock_nsec;
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__u32 tb_seq_count; /* Timebase sequence counter */
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__u32 cs_mult; /* Clocksource multiplier */
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__u32 cs_shift; /* Clocksource shift */
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__u32 tz_minuteswest; /* Whacky timezone stuff */
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__u32 tz_dsttime;
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__u32 use_syscall;
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};
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#endif /* !__ASSEMBLY__ */
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#endif /* __KERNEL__ */
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#endif /* __ASM_VDSO_DATAPAGE_H */
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@ -0,0 +1,261 @@
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/*
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* VDSO implementation for AArch64 and vector page setup for AArch32.
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*
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* Copyright (C) 2012 ARM Limited
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License version 2 as
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* published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program. If not, see <http://www.gnu.org/licenses/>.
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*
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* Author: Will Deacon <will.deacon@arm.com>
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*/
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#include <linux/kernel.h>
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#include <linux/clocksource.h>
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#include <linux/elf.h>
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#include <linux/err.h>
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#include <linux/errno.h>
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#include <linux/gfp.h>
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#include <linux/mm.h>
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#include <linux/sched.h>
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#include <linux/signal.h>
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#include <linux/slab.h>
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#include <linux/vmalloc.h>
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#include <asm/cacheflush.h>
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#include <asm/signal32.h>
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#include <asm/vdso.h>
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#include <asm/vdso_datapage.h>
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extern char vdso_start, vdso_end;
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static unsigned long vdso_pages;
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static struct page **vdso_pagelist;
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/*
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* The vDSO data page.
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*/
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static union {
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struct vdso_data data;
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u8 page[PAGE_SIZE];
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} vdso_data_store __page_aligned_data;
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struct vdso_data *vdso_data = &vdso_data_store.data;
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#ifdef CONFIG_COMPAT
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/*
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* Create and map the vectors page for AArch32 tasks.
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*/
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static struct page *vectors_page[1];
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static int alloc_vectors_page(void)
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{
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extern char __kuser_helper_start[], __kuser_helper_end[];
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int kuser_sz = __kuser_helper_end - __kuser_helper_start;
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unsigned long vpage;
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vpage = get_zeroed_page(GFP_ATOMIC);
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if (!vpage)
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return -ENOMEM;
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/* kuser helpers */
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memcpy((void *)vpage + 0x1000 - kuser_sz, __kuser_helper_start,
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kuser_sz);
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/* sigreturn code */
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memcpy((void *)vpage + AARCH32_KERN_SIGRET_CODE_OFFSET,
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aarch32_sigret_code, sizeof(aarch32_sigret_code));
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flush_icache_range(vpage, vpage + PAGE_SIZE);
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vectors_page[0] = virt_to_page(vpage);
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return 0;
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}
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arch_initcall(alloc_vectors_page);
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int aarch32_setup_vectors_page(struct linux_binprm *bprm, int uses_interp)
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{
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struct mm_struct *mm = current->mm;
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unsigned long addr = AARCH32_VECTORS_BASE;
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int ret;
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down_write(&mm->mmap_sem);
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current->mm->context.vdso = (void *)addr;
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/* Map vectors page at the high address. */
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ret = install_special_mapping(mm, addr, PAGE_SIZE,
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VM_READ|VM_EXEC|VM_MAYREAD|VM_MAYEXEC,
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vectors_page);
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up_write(&mm->mmap_sem);
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return ret;
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}
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#endif /* CONFIG_COMPAT */
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static int __init vdso_init(void)
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{
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struct page *pg;
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char *vbase;
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int i, ret = 0;
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vdso_pages = (&vdso_end - &vdso_start) >> PAGE_SHIFT;
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pr_info("vdso: %ld pages (%ld code, %ld data) at base %p\n",
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vdso_pages + 1, vdso_pages, 1L, &vdso_start);
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/* Allocate the vDSO pagelist, plus a page for the data. */
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vdso_pagelist = kzalloc(sizeof(struct page *) * (vdso_pages + 1),
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GFP_KERNEL);
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if (vdso_pagelist == NULL) {
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pr_err("Failed to allocate vDSO pagelist!\n");
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return -ENOMEM;
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}
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/* Grab the vDSO code pages. */
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for (i = 0; i < vdso_pages; i++) {
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pg = virt_to_page(&vdso_start + i*PAGE_SIZE);
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ClearPageReserved(pg);
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get_page(pg);
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vdso_pagelist[i] = pg;
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}
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/* Sanity check the shared object header. */
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vbase = vmap(vdso_pagelist, 1, 0, PAGE_KERNEL);
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if (vbase == NULL) {
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pr_err("Failed to map vDSO pagelist!\n");
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return -ENOMEM;
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} else if (memcmp(vbase, "\177ELF", 4)) {
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pr_err("vDSO is not a valid ELF object!\n");
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ret = -EINVAL;
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goto unmap;
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}
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/* Grab the vDSO data page. */
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pg = virt_to_page(vdso_data);
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get_page(pg);
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vdso_pagelist[i] = pg;
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unmap:
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vunmap(vbase);
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return ret;
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}
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arch_initcall(vdso_init);
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int arch_setup_additional_pages(struct linux_binprm *bprm,
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int uses_interp)
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{
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struct mm_struct *mm = current->mm;
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unsigned long vdso_base, vdso_mapping_len;
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int ret;
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/* Be sure to map the data page */
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vdso_mapping_len = (vdso_pages + 1) << PAGE_SHIFT;
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down_write(&mm->mmap_sem);
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vdso_base = get_unmapped_area(NULL, 0, vdso_mapping_len, 0, 0);
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if (IS_ERR_VALUE(vdso_base)) {
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ret = vdso_base;
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goto up_fail;
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}
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mm->context.vdso = (void *)vdso_base;
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ret = install_special_mapping(mm, vdso_base, vdso_mapping_len,
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VM_READ|VM_EXEC|
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VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
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vdso_pagelist);
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if (ret) {
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mm->context.vdso = NULL;
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goto up_fail;
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}
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up_fail:
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up_write(&mm->mmap_sem);
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return ret;
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}
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const char *arch_vma_name(struct vm_area_struct *vma)
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{
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/*
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* We can re-use the vdso pointer in mm_context_t for identifying
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* the vectors page for compat applications. The vDSO will always
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* sit above TASK_UNMAPPED_BASE and so we don't need to worry about
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* it conflicting with the vectors base.
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*/
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if (vma->vm_mm && vma->vm_start == (long)vma->vm_mm->context.vdso) {
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#ifdef CONFIG_COMPAT
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if (vma->vm_start == AARCH32_VECTORS_BASE)
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return "[vectors]";
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#endif
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return "[vdso]";
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}
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return NULL;
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}
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/*
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* We define AT_SYSINFO_EHDR, so we need these function stubs to keep
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* Linux happy.
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*/
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int in_gate_area_no_mm(unsigned long addr)
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{
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return 0;
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}
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int in_gate_area(struct mm_struct *mm, unsigned long addr)
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{
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return 0;
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}
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struct vm_area_struct *get_gate_vma(struct mm_struct *mm)
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{
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return NULL;
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}
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/*
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* Update the vDSO data page to keep in sync with kernel timekeeping.
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*/
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void update_vsyscall(struct timespec *ts, struct timespec *wtm,
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struct clocksource *clock, u32 mult)
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{
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struct timespec xtime_coarse;
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u32 use_syscall = strcmp(clock->name, "arch_sys_counter");
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++vdso_data->tb_seq_count;
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smp_wmb();
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xtime_coarse = __current_kernel_time();
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vdso_data->use_syscall = use_syscall;
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vdso_data->xtime_coarse_sec = xtime_coarse.tv_sec;
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vdso_data->xtime_coarse_nsec = xtime_coarse.tv_nsec;
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if (!use_syscall) {
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vdso_data->cs_cycle_last = clock->cycle_last;
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vdso_data->xtime_clock_sec = ts->tv_sec;
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vdso_data->xtime_clock_nsec = ts->tv_nsec;
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vdso_data->cs_mult = mult;
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vdso_data->cs_shift = clock->shift;
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vdso_data->wtm_clock_sec = wtm->tv_sec;
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vdso_data->wtm_clock_nsec = wtm->tv_nsec;
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}
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smp_wmb();
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++vdso_data->tb_seq_count;
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}
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void update_vsyscall_tz(void)
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{
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++vdso_data->tb_seq_count;
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smp_wmb();
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vdso_data->tz_minuteswest = sys_tz.tz_minuteswest;
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vdso_data->tz_dsttime = sys_tz.tz_dsttime;
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smp_wmb();
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++vdso_data->tb_seq_count;
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}
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@ -0,0 +1,2 @@
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vdso.lds
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vdso-offsets.h
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@ -0,0 +1,63 @@
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#
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# Building a vDSO image for AArch64.
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#
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# Author: Will Deacon <will.deacon@arm.com>
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# Heavily based on the vDSO Makefiles for other archs.
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#
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obj-vdso := gettimeofday.o note.o sigreturn.o
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# Build rules
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targets := $(obj-vdso) vdso.so vdso.so.dbg
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obj-vdso := $(addprefix $(obj)/, $(obj-vdso))
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ccflags-y := -shared -fno-common -fno-builtin
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ccflags-y += -nostdlib -Wl,-soname=linux-vdso.so.1 \
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$(call cc-ldoption, -Wl$(comma)--hash-style=sysv)
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obj-y += vdso.o
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extra-y += vdso.lds vdso-offsets.h
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CPPFLAGS_vdso.lds += -P -C -U$(ARCH)
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# Force dependency (incbin is bad)
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$(obj)/vdso.o : $(obj)/vdso.so
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# Link rule for the .so file, .lds has to be first
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$(obj)/vdso.so.dbg: $(src)/vdso.lds $(obj-vdso)
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$(call if_changed,vdsold)
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# Strip rule for the .so file
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$(obj)/%.so: OBJCOPYFLAGS := -S
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$(obj)/%.so: $(obj)/%.so.dbg FORCE
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$(call if_changed,objcopy)
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# Generate VDSO offsets using helper script
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gen-vdsosym := $(srctree)/$(src)/gen_vdso_offsets.sh
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quiet_cmd_vdsosym = VDSOSYM $@
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define cmd_vdsosym
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$(NM) $< | $(gen-vdsosym) | LC_ALL=C sort > $@ && \
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cp $@ include/generated/
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endef
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$(obj)/vdso-offsets.h: $(obj)/vdso.so.dbg FORCE
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$(call if_changed,vdsosym)
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# Assembly rules for the .S files
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$(obj-vdso): %.o: %.S
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$(call if_changed_dep,vdsoas)
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# Actual build commands
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quiet_cmd_vdsold = VDSOL $@
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cmd_vdsold = $(CC) $(c_flags) -Wl,-T $^ -o $@
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quiet_cmd_vdsoas = VDSOA $@
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cmd_vdsoas = $(CC) $(a_flags) -c -o $@ $<
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# Install commands for the unstripped file
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quiet_cmd_vdso_install = INSTALL $@
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cmd_vdso_install = cp $(obj)/$@.dbg $(MODLIB)/vdso/$@
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vdso.so: $(obj)/vdso.so.dbg
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@mkdir -p $(MODLIB)/vdso
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$(call cmd,vdso_install)
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vdso_install: vdso.so
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@ -0,0 +1,15 @@
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#!/bin/sh
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#
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# Match symbols in the DSO that look like VDSO_*; produce a header file
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# of constant offsets into the shared object.
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#
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# Doing this inside the Makefile will break the $(filter-out) function,
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# causing Kbuild to rebuild the vdso-offsets header file every time.
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#
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# Author: Will Deacon <will.deacon@arm.com
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#
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LC_ALL=C
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sed -n -e 's/^00*/0/' -e \
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's/^\([0-9a-fA-F]*\) . VDSO_\([a-zA-Z0-9_]*\)$/\#define vdso_offset_\2\t0x\1/p'
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@ -0,0 +1,242 @@
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/*
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* Userspace implementations of gettimeofday() and friends.
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*
|
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* Copyright (C) 2012 ARM Limited
|
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*
|
||||
* 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 <http://www.gnu.org/licenses/>.
|
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*
|
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* Author: Will Deacon <will.deacon@arm.com>
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*/
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#include <linux/linkage.h>
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#include <asm/asm-offsets.h>
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#include <asm/unistd.h>
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#define NSEC_PER_SEC_LO16 0xca00
|
||||
#define NSEC_PER_SEC_HI16 0x3b9a
|
||||
|
||||
vdso_data .req x6
|
||||
use_syscall .req w7
|
||||
seqcnt .req w8
|
||||
|
||||
.macro seqcnt_acquire
|
||||
9999: ldr seqcnt, [vdso_data, #VDSO_TB_SEQ_COUNT]
|
||||
tbnz seqcnt, #0, 9999b
|
||||
dmb ishld
|
||||
ldr use_syscall, [vdso_data, #VDSO_USE_SYSCALL]
|
||||
.endm
|
||||
|
||||
.macro seqcnt_read, cnt
|
||||
dmb ishld
|
||||
ldr \cnt, [vdso_data, #VDSO_TB_SEQ_COUNT]
|
||||
.endm
|
||||
|
||||
.macro seqcnt_check, cnt, fail
|
||||
cmp \cnt, seqcnt
|
||||
b.ne \fail
|
||||
.endm
|
||||
|
||||
.text
|
||||
|
||||
/* int __kernel_gettimeofday(struct timeval *tv, struct timezone *tz); */
|
||||
ENTRY(__kernel_gettimeofday)
|
||||
.cfi_startproc
|
||||
mov x2, x30
|
||||
.cfi_register x30, x2
|
||||
|
||||
/* Acquire the sequence counter and get the timespec. */
|
||||
adr vdso_data, _vdso_data
|
||||
1: seqcnt_acquire
|
||||
cbnz use_syscall, 4f
|
||||
|
||||
/* If tv is NULL, skip to the timezone code. */
|
||||
cbz x0, 2f
|
||||
bl __do_get_tspec
|
||||
seqcnt_check w13, 1b
|
||||
|
||||
/* Convert ns to us. */
|
||||
mov x11, #1000
|
||||
udiv x10, x10, x11
|
||||
stp x9, x10, [x0, #TVAL_TV_SEC]
|
||||
2:
|
||||
/* If tz is NULL, return 0. */
|
||||
cbz x1, 3f
|
||||
ldp w4, w5, [vdso_data, #VDSO_TZ_MINWEST]
|
||||
seqcnt_read w13
|
||||
seqcnt_check w13, 1b
|
||||
stp w4, w5, [x1, #TZ_MINWEST]
|
||||
3:
|
||||
mov x0, xzr
|
||||
ret x2
|
||||
4:
|
||||
/* Syscall fallback. */
|
||||
mov x8, #__NR_gettimeofday
|
||||
svc #0
|
||||
ret x2
|
||||
.cfi_endproc
|
||||
ENDPROC(__kernel_gettimeofday)
|
||||
|
||||
/* int __kernel_clock_gettime(clockid_t clock_id, struct timespec *tp); */
|
||||
ENTRY(__kernel_clock_gettime)
|
||||
.cfi_startproc
|
||||
cmp w0, #CLOCK_REALTIME
|
||||
ccmp w0, #CLOCK_MONOTONIC, #0x4, ne
|
||||
b.ne 2f
|
||||
|
||||
mov x2, x30
|
||||
.cfi_register x30, x2
|
||||
|
||||
/* Get kernel timespec. */
|
||||
adr vdso_data, _vdso_data
|
||||
1: seqcnt_acquire
|
||||
cbnz use_syscall, 7f
|
||||
|
||||
bl __do_get_tspec
|
||||
seqcnt_check w13, 1b
|
||||
|
||||
cmp w0, #CLOCK_MONOTONIC
|
||||
b.ne 6f
|
||||
|
||||
/* Get wtm timespec. */
|
||||
ldp x14, x15, [vdso_data, #VDSO_WTM_CLK_SEC]
|
||||
|
||||
/* Check the sequence counter. */
|
||||
seqcnt_read w13
|
||||
seqcnt_check w13, 1b
|
||||
b 4f
|
||||
2:
|
||||
cmp w0, #CLOCK_REALTIME_COARSE
|
||||
ccmp w0, #CLOCK_MONOTONIC_COARSE, #0x4, ne
|
||||
b.ne 8f
|
||||
|
||||
/* Get coarse timespec. */
|
||||
adr vdso_data, _vdso_data
|
||||
3: seqcnt_acquire
|
||||
ldp x9, x10, [vdso_data, #VDSO_XTIME_CRS_SEC]
|
||||
|
||||
cmp w0, #CLOCK_MONOTONIC_COARSE
|
||||
b.ne 6f
|
||||
|
||||
/* Get wtm timespec. */
|
||||
ldp x14, x15, [vdso_data, #VDSO_WTM_CLK_SEC]
|
||||
|
||||
/* Check the sequence counter. */
|
||||
seqcnt_read w13
|
||||
seqcnt_check w13, 3b
|
||||
4:
|
||||
/* Add on wtm timespec. */
|
||||
add x9, x9, x14
|
||||
add x10, x10, x15
|
||||
|
||||
/* Normalise the new timespec. */
|
||||
mov x14, #NSEC_PER_SEC_LO16
|
||||
movk x14, #NSEC_PER_SEC_HI16, lsl #16
|
||||
cmp x10, x14
|
||||
b.lt 5f
|
||||
sub x10, x10, x14
|
||||
add x9, x9, #1
|
||||
5:
|
||||
cmp x10, #0
|
||||
b.ge 6f
|
||||
add x10, x10, x14
|
||||
sub x9, x9, #1
|
||||
|
||||
6: /* Store to the user timespec. */
|
||||
stp x9, x10, [x1, #TSPEC_TV_SEC]
|
||||
mov x0, xzr
|
||||
ret x2
|
||||
7:
|
||||
mov x30, x2
|
||||
8: /* Syscall fallback. */
|
||||
mov x8, #__NR_clock_gettime
|
||||
svc #0
|
||||
ret
|
||||
.cfi_endproc
|
||||
ENDPROC(__kernel_clock_gettime)
|
||||
|
||||
/* int __kernel_clock_getres(clockid_t clock_id, struct timespec *res); */
|
||||
ENTRY(__kernel_clock_getres)
|
||||
.cfi_startproc
|
||||
cbz w1, 3f
|
||||
|
||||
cmp w0, #CLOCK_REALTIME
|
||||
ccmp w0, #CLOCK_MONOTONIC, #0x4, ne
|
||||
b.ne 1f
|
||||
|
||||
ldr x2, 5f
|
||||
b 2f
|
||||
1:
|
||||
cmp w0, #CLOCK_REALTIME_COARSE
|
||||
ccmp w0, #CLOCK_MONOTONIC_COARSE, #0x4, ne
|
||||
b.ne 4f
|
||||
ldr x2, 6f
|
||||
2:
|
||||
stp xzr, x2, [x1]
|
||||
|
||||
3: /* res == NULL. */
|
||||
mov w0, wzr
|
||||
ret
|
||||
|
||||
4: /* Syscall fallback. */
|
||||
mov x8, #__NR_clock_getres
|
||||
svc #0
|
||||
ret
|
||||
5:
|
||||
.quad CLOCK_REALTIME_RES
|
||||
6:
|
||||
.quad CLOCK_COARSE_RES
|
||||
.cfi_endproc
|
||||
ENDPROC(__kernel_clock_getres)
|
||||
|
||||
/*
|
||||
* Read the current time from the architected counter.
|
||||
* Expects vdso_data to be initialised.
|
||||
* Clobbers the temporary registers (x9 - x15).
|
||||
* Returns:
|
||||
* - (x9, x10) = (ts->tv_sec, ts->tv_nsec)
|
||||
* - (x11, x12) = (xtime->tv_sec, xtime->tv_nsec)
|
||||
* - w13 = vDSO sequence counter
|
||||
*/
|
||||
ENTRY(__do_get_tspec)
|
||||
.cfi_startproc
|
||||
|
||||
/* Read from the vDSO data page. */
|
||||
ldr x10, [vdso_data, #VDSO_CS_CYCLE_LAST]
|
||||
ldp x11, x12, [vdso_data, #VDSO_XTIME_CLK_SEC]
|
||||
ldp w14, w15, [vdso_data, #VDSO_CS_MULT]
|
||||
seqcnt_read w13
|
||||
|
||||
/* Read the physical counter. */
|
||||
isb
|
||||
mrs x9, cntpct_el0
|
||||
|
||||
/* Calculate cycle delta and convert to ns. */
|
||||
sub x10, x9, x10
|
||||
/* We can only guarantee 56 bits of precision. */
|
||||
movn x9, #0xff0, lsl #48
|
||||
and x10, x9, x10
|
||||
mul x10, x10, x14
|
||||
lsr x10, x10, x15
|
||||
|
||||
/* Use the kernel time to calculate the new timespec. */
|
||||
add x10, x12, x10
|
||||
mov x14, #NSEC_PER_SEC_LO16
|
||||
movk x14, #NSEC_PER_SEC_HI16, lsl #16
|
||||
udiv x15, x10, x14
|
||||
add x9, x15, x11
|
||||
mul x14, x14, x15
|
||||
sub x10, x10, x14
|
||||
|
||||
ret
|
||||
.cfi_endproc
|
||||
ENDPROC(__do_get_tspec)
|
||||
|
|
@ -0,0 +1,28 @@
|
|||
/*
|
||||
* 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 <http://www.gnu.org/licenses/>.
|
||||
*
|
||||
* Author: Will Deacon <will.deacon@arm.com>
|
||||
*
|
||||
* This supplies .note.* sections to go into the PT_NOTE inside the vDSO text.
|
||||
* Here we can supply some information useful to userland.
|
||||
*/
|
||||
|
||||
#include <linux/uts.h>
|
||||
#include <linux/version.h>
|
||||
#include <linux/elfnote.h>
|
||||
|
||||
ELFNOTE_START(Linux, 0, "a")
|
||||
.long LINUX_VERSION_CODE
|
||||
ELFNOTE_END
|
||||
|
|
@ -0,0 +1,37 @@
|
|||
/*
|
||||
* Sigreturn trampoline for returning from a signal when the SA_RESTORER
|
||||
* flag is not set.
|
||||
*
|
||||
* 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 <http://www.gnu.org/licenses/>.
|
||||
*
|
||||
* Author: Will Deacon <will.deacon@arm.com>
|
||||
*/
|
||||
|
||||
#include <linux/linkage.h>
|
||||
#include <asm/unistd.h>
|
||||
|
||||
.text
|
||||
|
||||
nop
|
||||
ENTRY(__kernel_rt_sigreturn)
|
||||
.cfi_startproc
|
||||
.cfi_signal_frame
|
||||
.cfi_def_cfa x29, 0
|
||||
.cfi_offset x29, 0 * 8
|
||||
.cfi_offset x30, 1 * 8
|
||||
mov x8, #__NR_rt_sigreturn
|
||||
svc #0
|
||||
.cfi_endproc
|
||||
ENDPROC(__kernel_rt_sigreturn)
|
||||
|
|
@ -0,0 +1,33 @@
|
|||
/*
|
||||
* 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 <http://www.gnu.org/licenses/>.
|
||||
*
|
||||
* Author: Will Deacon <will.deacon@arm.com>
|
||||
*/
|
||||
|
||||
#include <linux/init.h>
|
||||
#include <linux/linkage.h>
|
||||
#include <linux/const.h>
|
||||
#include <asm/page.h>
|
||||
|
||||
__PAGE_ALIGNED_DATA
|
||||
|
||||
.globl vdso_start, vdso_end
|
||||
.balign PAGE_SIZE
|
||||
vdso_start:
|
||||
.incbin "arch/arm64/kernel/vdso/vdso.so"
|
||||
.balign PAGE_SIZE
|
||||
vdso_end:
|
||||
|
||||
.previous
|
||||
|
|
@ -0,0 +1,100 @@
|
|||
/*
|
||||
* GNU linker script for the VDSO library.
|
||||
*
|
||||
* 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 <http://www.gnu.org/licenses/>.
|
||||
*
|
||||
* Author: Will Deacon <will.deacon@arm.com>
|
||||
* Heavily based on the vDSO linker scripts for other archs.
|
||||
*/
|
||||
|
||||
#include <linux/const.h>
|
||||
#include <asm/page.h>
|
||||
#include <asm/vdso.h>
|
||||
|
||||
OUTPUT_FORMAT("elf64-littleaarch64", "elf64-bigaarch64", "elf64-littleaarch64")
|
||||
OUTPUT_ARCH(aarch64)
|
||||
|
||||
SECTIONS
|
||||
{
|
||||
. = VDSO_LBASE + SIZEOF_HEADERS;
|
||||
|
||||
.hash : { *(.hash) } :text
|
||||
.gnu.hash : { *(.gnu.hash) }
|
||||
.dynsym : { *(.dynsym) }
|
||||
.dynstr : { *(.dynstr) }
|
||||
.gnu.version : { *(.gnu.version) }
|
||||
.gnu.version_d : { *(.gnu.version_d) }
|
||||
.gnu.version_r : { *(.gnu.version_r) }
|
||||
|
||||
.note : { *(.note.*) } :text :note
|
||||
|
||||
. = ALIGN(16);
|
||||
|
||||
.text : { *(.text*) } :text =0xd503201f
|
||||
PROVIDE (__etext = .);
|
||||
PROVIDE (_etext = .);
|
||||
PROVIDE (etext = .);
|
||||
|
||||
.eh_frame_hdr : { *(.eh_frame_hdr) } :text :eh_frame_hdr
|
||||
.eh_frame : { KEEP (*(.eh_frame)) } :text
|
||||
|
||||
.dynamic : { *(.dynamic) } :text :dynamic
|
||||
|
||||
.rodata : { *(.rodata*) } :text
|
||||
|
||||
_end = .;
|
||||
PROVIDE(end = .);
|
||||
|
||||
. = ALIGN(PAGE_SIZE);
|
||||
PROVIDE(_vdso_data = .);
|
||||
|
||||
/DISCARD/ : {
|
||||
*(.note.GNU-stack)
|
||||
*(.data .data.* .gnu.linkonce.d.* .sdata*)
|
||||
*(.bss .sbss .dynbss .dynsbss)
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
* We must supply the ELF program headers explicitly to get just one
|
||||
* PT_LOAD segment, and set the flags explicitly to make segments read-only.
|
||||
*/
|
||||
PHDRS
|
||||
{
|
||||
text PT_LOAD FLAGS(5) FILEHDR PHDRS; /* PF_R|PF_X */
|
||||
dynamic PT_DYNAMIC FLAGS(4); /* PF_R */
|
||||
note PT_NOTE FLAGS(4); /* PF_R */
|
||||
eh_frame_hdr PT_GNU_EH_FRAME;
|
||||
}
|
||||
|
||||
/*
|
||||
* This controls what symbols we export from the DSO.
|
||||
*/
|
||||
VERSION
|
||||
{
|
||||
LINUX_2.6.39 {
|
||||
global:
|
||||
__kernel_rt_sigreturn;
|
||||
__kernel_gettimeofday;
|
||||
__kernel_clock_gettime;
|
||||
__kernel_clock_getres;
|
||||
local: *;
|
||||
};
|
||||
}
|
||||
|
||||
/*
|
||||
* Make the sigreturn code visible to the kernel.
|
||||
*/
|
||||
VDSO_sigtramp = __kernel_rt_sigreturn;
|
||||
Loading…
Reference in New Issue