--- zzzz-none-000/linux-3.10.107/arch/mips/kernel/vdso.c 2017-06-27 09:49:32.000000000 +0000 +++ scorpion-7490-727/linux-3.10.107/arch/mips/kernel/vdso.c 2021-02-04 17:41:59.000000000 +0000 @@ -1,109 +1,175 @@ /* - * This file is subject to the terms and conditions of the GNU General Public - * License. See the file "COPYING" in the main directory of this archive - * for more details. + * Copyright (C) 2015 Imagination Technologies + * Author: Alex Smith * - * Copyright (C) 2009, 2010 Cavium Networks, Inc. + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. */ - -#include -#include -#include -#include -#include #include #include -#include -#include +#include +#include +#include +#include +#include +#include +#include +#include +#include #include -#include + +/* Kernel-provided data used by the VDSO. */ +static union mips_vdso_data vdso_data __page_aligned_data; /* - * Including would give use the 64-bit syscall numbers ... + * Mapping for the VDSO data/GIC pages. The real pages are mapped manually, as + * what we map and where within the area they are mapped is determined at + * runtime. */ -#define __NR_O32_sigreturn 4119 -#define __NR_O32_rt_sigreturn 4193 -#define __NR_N32_rt_sigreturn 6211 +static struct page *no_pages[] = { NULL }; +static struct vm_special_mapping vdso_vvar_mapping = { + .name = "[vvar]", + .pages = no_pages, +}; -static struct page *vdso_page; - -static void __init install_trampoline(u32 *tramp, unsigned int sigreturn) +static void __init init_vdso_image(struct mips_vdso_image *image) { - uasm_i_addiu(&tramp, 2, 0, sigreturn); /* li v0, sigreturn */ - uasm_i_syscall(&tramp, 0); + unsigned long num_pages, i; + unsigned long data_pfn; + + BUG_ON(!PAGE_ALIGNED(image->data)); + BUG_ON(!PAGE_ALIGNED(image->size)); + + num_pages = image->size / PAGE_SIZE; + + data_pfn = __phys_to_pfn(__pa_symbol(image->data)); + for (i = 0; i < num_pages; i++) + image->mapping.pages[i] = pfn_to_page(data_pfn + i); } static int __init init_vdso(void) { - struct mips_vdso *vdso; + init_vdso_image(&vdso_image); - vdso_page = alloc_page(GFP_KERNEL); - if (!vdso_page) - panic("Cannot allocate vdso"); - - vdso = vmap(&vdso_page, 1, 0, PAGE_KERNEL); - if (!vdso) - panic("Cannot map vdso"); - clear_page(vdso); - - install_trampoline(vdso->rt_signal_trampoline, __NR_rt_sigreturn); -#ifdef CONFIG_32BIT - install_trampoline(vdso->signal_trampoline, __NR_sigreturn); -#else - install_trampoline(vdso->n32_rt_signal_trampoline, - __NR_N32_rt_sigreturn); - install_trampoline(vdso->o32_signal_trampoline, __NR_O32_sigreturn); - install_trampoline(vdso->o32_rt_signal_trampoline, - __NR_O32_rt_sigreturn); +#ifdef CONFIG_MIPS32_O32 + init_vdso_image(&vdso_image_o32); #endif - vunmap(vdso); +#ifdef CONFIG_MIPS32_N32 + init_vdso_image(&vdso_image_n32); +#endif return 0; } subsys_initcall(init_vdso); -static unsigned long vdso_addr(unsigned long start) +void update_vsyscall(struct timekeeper *tk) +{ + vdso_data_write_begin(&vdso_data); + + vdso_data.xtime_sec = tk->xtime_sec; + vdso_data.xtime_nsec = tk->tkr_mono.xtime_nsec; + vdso_data.wall_to_mono_sec = tk->wall_to_monotonic.tv_sec; + vdso_data.wall_to_mono_nsec = tk->wall_to_monotonic.tv_nsec; + vdso_data.cs_shift = tk->tkr_mono.shift; + + vdso_data.clock_mode = tk->tkr_mono.clock->archdata.vdso_clock_mode; + if (vdso_data.clock_mode != VDSO_CLOCK_NONE) { + vdso_data.cs_mult = tk->tkr_mono.mult; + vdso_data.cs_cycle_last = tk->tkr_mono.cycle_last; + vdso_data.cs_mask = tk->tkr_mono.mask; + } + + vdso_data_write_end(&vdso_data); +} + +void update_vsyscall_tz(void) { - return STACK_TOP; + if (vdso_data.clock_mode != VDSO_CLOCK_NONE) { + vdso_data.tz_minuteswest = sys_tz.tz_minuteswest; + vdso_data.tz_dsttime = sys_tz.tz_dsttime; + } } int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) { - int ret; - unsigned long addr; + struct mips_vdso_image *image = current->thread.abi->vdso; struct mm_struct *mm = current->mm; + unsigned long gic_size, vvar_size, size, base, data_addr, vdso_addr; + struct vm_area_struct *vma; + struct resource gic_res; + int ret; down_write(&mm->mmap_sem); - addr = vdso_addr(mm->start_stack); + /* + * Determine total area size. This includes the VDSO data itself, the + * data page, and the GIC user page if present. Always create a mapping + * for the GIC user area if the GIC is present regardless of whether it + * is the current clocksource, in case it comes into use later on. We + * only map a page even though the total area is 64K, as we only need + * the counter registers at the start. + */ + gic_size = gic_present ? PAGE_SIZE : 0; + vvar_size = gic_size + PAGE_SIZE; + size = vvar_size + image->size; + + base = get_unmapped_area(NULL, 0, size, 0, 0); + if (IS_ERR_VALUE(base)) { + ret = base; + goto out; + } + + data_addr = base + gic_size; + vdso_addr = data_addr + PAGE_SIZE; - addr = get_unmapped_area(NULL, addr, PAGE_SIZE, 0, 0); - if (IS_ERR_VALUE(addr)) { - ret = addr; - goto up_fail; + vma = _install_special_mapping(mm, base, vvar_size, + VM_READ | VM_MAYREAD, + &vdso_vvar_mapping); + if (IS_ERR(vma)) { + ret = PTR_ERR(vma); + goto out; } - ret = install_special_mapping(mm, addr, PAGE_SIZE, - VM_READ|VM_EXEC| - VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC, - &vdso_page); + /* Map GIC user page. */ + if (gic_size) { + ret = gic_get_usm_range(&gic_res); + if (ret) + goto out; + + ret = io_remap_pfn_range(vma, base, + gic_res.start >> PAGE_SHIFT, + gic_size, + pgprot_noncached(PAGE_READONLY)); + if (ret) + goto out; + } + /* Map data page. */ + ret = remap_pfn_range(vma, data_addr, + virt_to_phys(&vdso_data) >> PAGE_SHIFT, + PAGE_SIZE, PAGE_READONLY); if (ret) - goto up_fail; + goto out; + + /* Map VDSO image. */ + vma = _install_special_mapping(mm, vdso_addr, image->size, + VM_READ | VM_EXEC | + VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC, + &image->mapping); + if (IS_ERR(vma)) { + ret = PTR_ERR(vma); + goto out; + } - mm->context.vdso = (void *)addr; + mm->context.vdso = (void *)vdso_addr; + ret = 0; -up_fail: +out: up_write(&mm->mmap_sem); return ret; } - -const char *arch_vma_name(struct vm_area_struct *vma) -{ - if (vma->vm_mm && vma->vm_start == (long)vma->vm_mm->context.vdso) - return "[vdso]"; - return NULL; -}