diff options
Diffstat (limited to 'arch/csky/kernel/vdso.c')
-rw-r--r-- | arch/csky/kernel/vdso.c | 86 |
1 files changed, 86 insertions, 0 deletions
diff --git a/arch/csky/kernel/vdso.c b/arch/csky/kernel/vdso.c new file mode 100644 index 000000000..abc3dbc65 --- /dev/null +++ b/arch/csky/kernel/vdso.c @@ -0,0 +1,86 @@ +// 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; + + 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); + + err = setup_vdso_page(vdso->rt_signal_retcode); + if (err) + panic("Cannot set signal return code, err: %x.", err); + + dcache_wb_range((unsigned long)vdso, (unsigned long)vdso + 16); + + vunmap(vdso); + + return 0; +} +subsys_initcall(init_vdso); + +int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp) +{ + int ret; + unsigned long addr; + struct mm_struct *mm = current->mm; + + mmap_write_lock(mm); + + addr = get_unmapped_area(NULL, STACK_TOP, PAGE_SIZE, 0, 0); + if (IS_ERR_VALUE(addr)) { + ret = addr; + goto up_fail; + } + + 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; + +up_fail: + 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; +} |