diff options
Diffstat (limited to 'arch/csky/kernel/vdso.c')
-rw-r--r-- | arch/csky/kernel/vdso.c | 122 |
1 files changed, 60 insertions, 62 deletions
diff --git a/arch/csky/kernel/vdso.c b/arch/csky/kernel/vdso.c index 60ff7adfad1d..c54d019d66bc 100644 --- a/arch/csky/kernel/vdso.c +++ b/arch/csky/kernel/vdso.c @@ -1,86 +1,84 @@ // SPDX-License-Identifier: GPL-2.0 // Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd. -#include <linux/kernel.h> -#include <linux/err.h> -#include <linux/sched.h> -#include <linux/mm.h> -#include <linux/init.h> #include <linux/binfmts.h> #include <linux/elf.h> -#include <linux/vmalloc.h> -#include <linux/unistd.h> -#include <linux/uaccess.h> - -#include <asm/vdso.h> -#include <asm/cacheflush.h> - -static struct page *vdso_page; - -static int __init init_vdso(void) -{ - struct csky_vdso *vdso; - int err = 0; +#include <linux/err.h> +#include <linux/mm.h> +#include <linux/slab.h> - vdso_page = alloc_page(GFP_KERNEL); - if (!vdso_page) - panic("Cannot allocate vdso"); +#include <asm/page.h> - vdso = vmap(&vdso_page, 1, 0, PAGE_KERNEL); - if (!vdso) - panic("Cannot map vdso"); +extern char vdso_start[], vdso_end[]; - clear_page(vdso); +static unsigned int vdso_pages; +static struct page **vdso_pagelist; - err = setup_vdso_page(vdso->rt_signal_retcode); - if (err) - panic("Cannot set signal return code, err: %x.", err); +static int __init vdso_init(void) +{ + unsigned int i; + + vdso_pages = (vdso_end - vdso_start) >> PAGE_SHIFT; + vdso_pagelist = + kcalloc(vdso_pages, sizeof(struct page *), GFP_KERNEL); + if (unlikely(vdso_pagelist == NULL)) { + pr_err("vdso: pagelist allocation failed\n"); + return -ENOMEM; + } - dcache_wb_range((unsigned long)vdso, (unsigned long)vdso + 16); + for (i = 0; i < vdso_pages; i++) { + struct page *pg; - vunmap(vdso); + pg = virt_to_page(vdso_start + (i << PAGE_SHIFT)); + vdso_pagelist[i] = pg; + } return 0; } -subsys_initcall(init_vdso); +arch_initcall(vdso_init); -int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) +int arch_setup_additional_pages(struct linux_binprm *bprm, + int uses_interp) { - int ret; - unsigned long addr; + struct vm_area_struct *vma; struct mm_struct *mm = current->mm; + unsigned long vdso_base, vdso_len; + int ret; + static struct vm_special_mapping vdso_mapping = { + .name = "[vdso]", + }; - down_write(&mm->mmap_sem); + vdso_len = vdso_pages << PAGE_SHIFT; - addr = get_unmapped_area(NULL, STACK_TOP, PAGE_SIZE, 0, 0); - if (IS_ERR_VALUE(addr)) { - ret = addr; - goto up_fail; + mmap_write_lock(mm); + vdso_base = get_unmapped_area(NULL, 0, vdso_len, 0, 0); + if (IS_ERR_VALUE(vdso_base)) { + ret = vdso_base; + goto end; } - ret = install_special_mapping( - mm, - addr, - PAGE_SIZE, - VM_READ|VM_EXEC|VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC, - &vdso_page); - if (ret) - goto up_fail; - - mm->context.vdso = (void *)addr; + /* + * Put vDSO base into mm struct. We need to do this before calling + * install_special_mapping or the perf counter mmap tracking code + * will fail to recognise it as a vDSO (since arch_vma_name fails). + */ + mm->context.vdso = (void *)vdso_base; + + vdso_mapping.pages = vdso_pagelist; + vma = + _install_special_mapping(mm, vdso_base, vdso_pages << PAGE_SHIFT, + (VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC), + &vdso_mapping); + + if (IS_ERR(vma)) { + ret = PTR_ERR(vma); + mm->context.vdso = NULL; + goto end; + } -up_fail: - up_write(&mm->mmap_sem); + vdso_base += (vdso_pages << PAGE_SHIFT); + ret = 0; +end: + mmap_write_unlock(mm); return ret; } - -const char *arch_vma_name(struct vm_area_struct *vma) -{ - if (vma->vm_mm == NULL) - return NULL; - - if (vma->vm_start == (long)vma->vm_mm->context.vdso) - return "[vdso]"; - else - return NULL; -} |