From 4bfbe371dbc508411162d1a62e3211ed9f47f614 Mon Sep 17 00:00:00 2001 From: Vlastimil Babka Date: Thu, 9 Mar 2023 12:12:58 +0100 Subject: mm/mremap: simplify vma expansion again This effectively reverts d014cd7c1c35 ("mm, mremap: fix mremap() expanding for vma's with vm_ops->close()"). After the recent changes, vma_merge() is able to handle the expansion properly even when the vma being expanded has a vm_ops->close operation, so we don't need to special case it anymore. Link: https://lkml.kernel.org/r/20230309111258.24079-11-vbabka@suse.cz Signed-off-by: Vlastimil Babka Reviewed-by: Lorenzo Stoakes Reviewed-by: Liam R. Howlett Cc: Matthew Wilcox (Oracle) Cc: Suren Baghdasaryan Signed-off-by: Andrew Morton --- mm/mremap.c | 20 ++++---------------- 1 file changed, 4 insertions(+), 16 deletions(-) (limited to 'mm/mremap.c') diff --git a/mm/mremap.c b/mm/mremap.c index 1ddf7beb62e9..0eaa11c845b9 100644 --- a/mm/mremap.c +++ b/mm/mremap.c @@ -1040,23 +1040,11 @@ SYSCALL_DEFINE5(mremap, unsigned long, addr, unsigned long, old_len, * vma (expand operation itself) and possibly also with * the next vma if it becomes adjacent to the expanded * vma and otherwise compatible. - * - * However, vma_merge() can currently fail due to - * is_mergeable_vma() check for vm_ops->close (see the - * comment there). Yet this should not prevent vma - * expanding, so perform a simple expand for such vma. - * Ideally the check for close op should be only done - * when a vma would be actually removed due to a merge. */ - if (!vma->vm_ops || !vma->vm_ops->close) { - vma = vma_merge(&vmi, mm, vma, extension_start, - extension_end, vma->vm_flags, vma->anon_vma, - vma->vm_file, extension_pgoff, vma_policy(vma), - vma->vm_userfaultfd_ctx, anon_vma_name(vma)); - } else if (vma_expand(&vmi, vma, vma->vm_start, - addr + new_len, vma->vm_pgoff, NULL)) { - vma = NULL; - } + vma = vma_merge(&vmi, mm, vma, extension_start, + extension_end, vma->vm_flags, vma->anon_vma, + vma->vm_file, extension_pgoff, vma_policy(vma), + vma->vm_userfaultfd_ctx, anon_vma_name(vma)); if (!vma) { vm_unacct_memory(pages); ret = -ENOMEM; -- cgit v1.2.3