tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
csky: VDSO and rt_sigreturn
This patch adds files related to VDSO and our VDSO only support
rt_sigreturn.
Signed-off-by: Guo Ren <ren_guo@c-sky.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
+138
+17
arch/csky/abiv1/inc/abi/vdso.h
+17
arch/csky/abiv1/inc/abi/vdso.h
···
1
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/* SPDX-License-Identifier: GPL-2.0 */
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3
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#include <linux/uaccess.h>
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static inline int setup_vdso_page(unsigned short *ptr)
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{
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int err = 0;
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9
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/* movi r1, 127 */
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err |= __put_user(0x67f1, ptr + 0);
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/* addi r1, (139 - 127) */
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err |= __put_user(0x20b1, ptr + 1);
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/* trap 0 */
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err |= __put_user(0x0008, ptr + 2);
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return err;
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}
+23
arch/csky/abiv2/inc/abi/vdso.h
+23
arch/csky/abiv2/inc/abi/vdso.h
···
1
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/* SPDX-License-Identifier: GPL-2.0 */
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#ifndef __ABI_CSKY_VDSO_H
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#define __ABI_CSKY_VDSO_H
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#include <linux/uaccess.h>
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static inline int setup_vdso_page(unsigned short *ptr)
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{
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int err = 0;
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/* movi r7, 173 */
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err |= __put_user(0xea07, ptr);
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err |= __put_user(0x008b, ptr+1);
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/* trap 0 */
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err |= __put_user(0xc000, ptr+2);
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err |= __put_user(0x2020, ptr+3);
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return err;
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}
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#endif /* __ABI_CSKY_STRING_H */
+12
arch/csky/include/asm/vdso.h
+12
arch/csky/include/asm/vdso.h
+86
arch/csky/kernel/vdso.c
+86
arch/csky/kernel/vdso.c
···
1
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// SPDX-License-Identifier: GPL-2.0
2
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// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
3
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4
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#include <linux/kernel.h>
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#include <linux/err.h>
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#include <linux/sched.h>
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#include <linux/mm.h>
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#include <linux/init.h>
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#include <linux/binfmts.h>
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#include <linux/elf.h>
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#include <linux/vmalloc.h>
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#include <linux/unistd.h>
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#include <linux/uaccess.h>
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#include <asm/vdso.h>
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#include <asm/cacheflush.h>
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static struct page *vdso_page;
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static int __init init_vdso(void)
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{
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struct csky_vdso *vdso;
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int err = 0;
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vdso_page = alloc_page(GFP_KERNEL);
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if (!vdso_page)
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panic("Cannot allocate vdso");
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vdso = vmap(&vdso_page, 1, 0, PAGE_KERNEL);
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if (!vdso)
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panic("Cannot map vdso");
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clear_page(vdso);
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err = setup_vdso_page(vdso->rt_signal_retcode);
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if (err)
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panic("Cannot set signal return code, err: %x.", err);
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dcache_wb_range((unsigned long)vdso, (unsigned long)vdso + 16);
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vunmap(vdso);
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43
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return 0;
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}
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subsys_initcall(init_vdso);
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int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
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{
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int ret;
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unsigned long addr;
51
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struct mm_struct *mm = current->mm;
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down_write(&mm->mmap_sem);
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addr = get_unmapped_area(NULL, STACK_TOP, PAGE_SIZE, 0, 0);
56
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if (IS_ERR_VALUE(addr)) {
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ret = addr;
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goto up_fail;
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}
60
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ret = install_special_mapping(
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mm,
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addr,
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PAGE_SIZE,
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VM_READ|VM_EXEC|VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
66
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&vdso_page);
67
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if (ret)
68
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goto up_fail;
69
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70
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mm->context.vdso = (void *)addr;
71
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72
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up_fail:
73
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up_write(&mm->mmap_sem);
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return ret;
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}
76
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77
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const char *arch_vma_name(struct vm_area_struct *vma)
78
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{
79
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if (vma->vm_mm == NULL)
80
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return NULL;
81
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82
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if (vma->vm_start == (long)vma->vm_mm->context.vdso)
83
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return "[vdso]";
84
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else
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return NULL;
86
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}