mirror of
git://git.kernel.org/pub/scm/linux/kernel/git/xiang/erofs.git
synced 2026-10-31 14:23:49 +01:00
Michel Lespinasse
d8ed45c5dc
This change converts the existing mmap_sem rwsem calls to use the new mmap locking API instead. The change is generated using coccinelle with the following rule: // spatch --sp-file mmap_lock_api.cocci --in-place --include-headers --dir . @@ expression mm; @@ ( -init_rwsem +mmap_init_lock | -down_write +mmap_write_lock | -down_write_killable +mmap_write_lock_killable | -down_write_trylock +mmap_write_trylock | -up_write +mmap_write_unlock | -downgrade_write +mmap_write_downgrade | -down_read +mmap_read_lock | -down_read_killable +mmap_read_lock_killable | -down_read_trylock +mmap_read_trylock | -up_read +mmap_read_unlock ) -(&mm->mmap_sem) +(mm) Signed-off-by: Michel Lespinasse <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Reviewed-by: Daniel Jordan <[email protected]> Reviewed-by: Laurent Dufour <[email protected]> Reviewed-by: Vlastimil Babka <[email protected]> Cc: Davidlohr Bueso <[email protected]> Cc: David Rientjes <[email protected]> Cc: Hugh Dickins <[email protected]> Cc: Jason Gunthorpe <[email protected]> Cc: Jerome Glisse <[email protected]> Cc: John Hubbard <[email protected]> Cc: Liam Howlett <[email protected]> Cc: Matthew Wilcox <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Ying Han <[email protected]> Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Linus Torvalds <[email protected]>
89 lines
1.9 KiB
C
89 lines
1.9 KiB
C
// SPDX-License-Identifier: GPL-2.0-only
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/*
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* vDSO implementation for Hexagon
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*
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* Copyright (c) 2011, The Linux Foundation. All rights reserved.
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*/
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#include <linux/err.h>
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#include <linux/mm.h>
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#include <linux/vmalloc.h>
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#include <linux/binfmts.h>
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#include <asm/vdso.h>
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static struct page *vdso_page;
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/* Create a vDSO page holding the signal trampoline.
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* We want this for a non-executable stack.
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*/
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static int __init vdso_init(void)
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{
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struct hexagon_vdso *vdso;
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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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/* Install the signal trampoline; currently looks like this:
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* r6 = #__NR_rt_sigreturn;
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* trap0(#1);
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*/
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vdso->rt_signal_trampoline[0] = __rt_sigtramp_template[0];
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vdso->rt_signal_trampoline[1] = __rt_sigtramp_template[1];
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vunmap(vdso);
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return 0;
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}
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arch_initcall(vdso_init);
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/*
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* Called from binfmt_elf. Create a VMA for the vDSO page.
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*/
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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 vdso_base;
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struct mm_struct *mm = current->mm;
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if (mmap_write_lock_killable(mm))
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return -EINTR;
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/* Try to get it loaded right near ld.so/glibc. */
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vdso_base = STACK_TOP;
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vdso_base = get_unmapped_area(NULL, vdso_base, PAGE_SIZE, 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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/* MAYWRITE to allow gdb to COW and set breakpoints. */
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ret = install_special_mapping(mm, vdso_base, PAGE_SIZE,
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VM_READ|VM_EXEC|
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VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC,
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&vdso_page);
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if (ret)
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goto up_fail;
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mm->context.vdso = (void *)vdso_base;
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up_fail:
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mmap_write_unlock(mm);
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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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if (vma->vm_mm && vma->vm_start == (long)vma->vm_mm->context.vdso)
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return "[vdso]";
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return NULL;
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}
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