From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 9A95EC05027 for ; Sat, 21 Jan 2023 01:07:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229923AbjAUBHw (ORCPT ); Fri, 20 Jan 2023 20:07:52 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60858 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229578AbjAUBH3 (ORCPT ); Fri, 20 Jan 2023 20:07:29 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9761273155 for ; Fri, 20 Jan 2023 17:07:27 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 3D327B829E6 for ; Sat, 21 Jan 2023 01:07:26 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id CC290C433D2; Sat, 21 Jan 2023 01:07:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1674263244; bh=sw/c7V+ezfOoUk6mD5SM8yH5fh41qdJgOKpgcTIARbM=; h=Date:To:From:Subject:From; b=ZOJ4soxNNUR8BM5FhZJ/96iyfK51qx7ARzlDhwFnJOO0QNvCI2dbmoOZ0TWdNlojb SDzD42C9hHbhrZbWvkiopWxPLlaqd5VkW3I9HaZ1zx5CgPP0SJO+y7yJm33qOPRH4A VJXueIbi/0nurvnaBb/74+0CDmTVf+3WrQBpsbys= Date: Fri, 20 Jan 2023 17:07:24 -0800 To: mm-commits@vger.kernel.org, Liam.Howlett@oracle.com, Liam.Howlett@Oracle.com, akpm@linux-foundation.org From: Andrew Morton Subject: + mm-mmap-dont-use-__vma_adjust-in-shift_arg_pages.patch added to mm-unstable branch Message-Id: <20230121010724.CC290C433D2@smtp.kernel.org> Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org The patch titled Subject: mm/mmap: don't use __vma_adjust() in shift_arg_pages() has been added to the -mm mm-unstable branch. Its filename is mm-mmap-dont-use-__vma_adjust-in-shift_arg_pages.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-mmap-dont-use-__vma_adjust-in-shift_arg_pages.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: "Liam R. Howlett" Subject: mm/mmap: don't use __vma_adjust() in shift_arg_pages() Date: Fri, 20 Jan 2023 11:26:46 -0500 Introduce shrink_vma() which uses the vma_prepare() and vma_complete() functions to reduce the vma coverage. Convert shift_arg_pages() to use expand_vma() and the new shrink_vma() function. Remove support from __vma_adjust() to reduce a vma size since shift_arg_pages() is the only user that shrinks a VMA in this way. Link: https://lkml.kernel.org/r/20230120162650.984577-46-Liam.Howlett@oracle.com Signed-off-by: Liam R. Howlett Signed-off-by: Andrew Morton --- --- a/fs/exec.c~mm-mmap-dont-use-__vma_adjust-in-shift_arg_pages +++ a/fs/exec.c @@ -699,7 +699,7 @@ static int shift_arg_pages(struct vm_are /* * cover the whole range: [new_start, old_end) */ - if (vma_adjust(&vmi, vma, new_start, old_end, vma->vm_pgoff)) + if (vma_expand(&vmi, vma, new_start, old_end, vma->vm_pgoff, NULL)) return -ENOMEM; /* @@ -733,7 +733,7 @@ static int shift_arg_pages(struct vm_are vma_prev(&vmi); /* Shrink the vma to just the new range */ - return vma_adjust(&vmi, vma, new_start, new_end, vma->vm_pgoff); + return vma_shrink(&vmi, vma, new_start, new_end, vma->vm_pgoff); } /* --- a/include/linux/mm.h~mm-mmap-dont-use-__vma_adjust-in-shift_arg_pages +++ a/include/linux/mm.h @@ -2831,17 +2831,11 @@ void anon_vma_interval_tree_verify(struc /* mmap.c */ extern int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin); -extern int __vma_adjust(struct vma_iterator *vmi, struct vm_area_struct *vma, unsigned long start, - unsigned long end, pgoff_t pgoff, struct vm_area_struct *expand); -static inline int vma_adjust(struct vma_iterator *vmi, - struct vm_area_struct *vma, unsigned long start, unsigned long end, - pgoff_t pgoff) -{ - return __vma_adjust(vmi, vma, start, end, pgoff, NULL); -} extern int vma_expand(struct vma_iterator *vmi, struct vm_area_struct *vma, unsigned long start, unsigned long end, pgoff_t pgoff, struct vm_area_struct *next); +extern int vma_shrink(struct vma_iterator *vmi, struct vm_area_struct *vma, + unsigned long start, unsigned long end, pgoff_t pgoff); extern struct vm_area_struct *vma_merge(struct vma_iterator *vmi, struct mm_struct *, struct vm_area_struct *prev, unsigned long addr, unsigned long end, unsigned long vm_flags, struct anon_vma *, --- a/mm/mmap.c~mm-mmap-dont-use-__vma_adjust-in-shift_arg_pages +++ a/mm/mmap.c @@ -685,6 +685,44 @@ int vma_expand(struct vma_iterator *vmi, nomem: return -ENOMEM; } + +/* + * vma_shrink() - Reduce an existing VMAs memory area + * @vmi: The vma iterator + * @vma: The VMA to modify + * @start: The new start + * @end: The new end + * + * Returns: 0 on success, -ENOMEM otherwise + */ +int vma_shrink(struct vma_iterator *vmi, struct vm_area_struct *vma, + unsigned long start, unsigned long end, pgoff_t pgoff) +{ + struct vma_prepare vp; + + WARN_ON((vma->vm_start != start) && (vma->vm_end != end)); + + if (vma_iter_prealloc(vmi)) + return -ENOMEM; + + init_vma_prep(&vp, vma); + vma_adjust_trans_huge(vma, start, end, 0); + vma_prepare(&vp); + + if (vma->vm_start < start) + vma_iter_clear(vmi, vma->vm_start, start); + + if (vma->vm_end > end) + vma_iter_clear(vmi, end, vma->vm_end); + + vma->vm_start = start; + vma->vm_end = end; + vma->vm_pgoff = pgoff; + vma_complete(&vp, vmi, vma->vm_mm); + validate_mm(vma->vm_mm); + return 0; +} + /* * We cannot adjust vm_start, vm_end, vm_pgoff fields of a vma that * is already present in an i_mmap tree without adjusting the tree. @@ -800,14 +838,7 @@ int __vma_adjust(struct vma_iterator *vm vma_prepare(&vma_prep); - if (vma->vm_start < start) - vma_iter_clear(vmi, vma->vm_start, start); - else if (start != vma->vm_start) - vma_changed = true; - - if (vma->vm_end > end) - vma_iter_clear(vmi, end, vma->vm_end); - else if (end != vma->vm_end) + if (start < vma->vm_start || end > vma->vm_end) vma_changed = true; vma->vm_start = start; @@ -820,7 +851,10 @@ int __vma_adjust(struct vma_iterator *vm if (adjust_next) { next->vm_start += adjust_next; next->vm_pgoff += adjust_next >> PAGE_SHIFT; - vma_iter_store(vmi, next); + if (adjust_next < 0) { + WARN_ON_ONCE(vma_changed); + vma_iter_store(vmi, next); + } } vma_complete(&vma_prep, vmi, mm); _ Patches currently in -mm which might be from Liam.Howlett@Oracle.com are maple_tree-add-mas_init-function.patch maple_tree-fix-potential-rcu-issue.patch maple_tree-reduce-user-error-potential.patch test_maple_tree-test-modifications-while-iterating.patch mm-expand-vma-iterator-interface.patch mm-mmap-convert-brk-to-use-vma-iterator.patch kernel-fork-convert-forking-to-using-the-vmi-iterator.patch mmap-convert-vma_link-vma-iterator.patch mm-mmap-remove-preallocation-from-do_mas_align_munmap.patch mmap-change-do_mas_munmap-and-do_mas_aligned_munmap-to-use-vma-iterator.patch mmap-convert-vma_expand-to-use-vma-iterator.patch mm-add-temporary-vma-iterator-versions-of-vma_merge-split_vma-and-__split_vma.patch ipc-shm-use-the-vma-iterator-for-munmap-calls.patch userfaultfd-use-vma-iterator.patch mm-change-mprotect_fixup-to-vma-iterator.patch mlock-convert-mlock-to-vma-iterator.patch coredump-convert-to-vma-iterator.patch mempolicy-convert-to-vma-iterator.patch task_mmu-convert-to-vma-iterator.patch sched-convert-to-vma-iterator.patch madvise-use-vmi-iterator-for-__split_vma-and-vma_merge.patch mmap-pass-through-vmi-iterator-to-__split_vma.patch mmap-use-vmi-version-of-vma_merge.patch mm-mremap-use-vmi-version-of-vma_merge.patch nommu-convert-nommu-to-using-the-vma-iterator.patch mm-switch-vma_merge-split_vma-and-__split_vma-to-vma-iterator.patch mmap-convert-__vma_adjust-to-use-vma-iterator.patch mm-pass-through-vma-iterator-to-__vma_adjust.patch madvise-use-split_vma-instead-of-__split_vma.patch mm-remove-unnecessary-write-to-vma-iterator-in-__vma_adjust.patch mm-pass-vma-iterator-through-to-__vma_adjust.patch mm-add-vma-iterator-to-vma_adjust-arguments.patch mmap-clean-up-mmap_region-unrolling.patch mm-change-munmap-splitting-order-and-move_vma.patch mm-mmap-move-anon_vma-setting-in-__vma_adjust.patch mm-mmap-refactor-locking-out-of-__vma_adjust.patch mm-mmap-use-vma_prepare-and-vma_complete-in-vma_expand.patch mm-mmap-introduce-init_vma_prep-and-init_multi_vma_prep.patch mm-dont-use-__vma_adjust-in-__split_vma.patch mm-mmap-dont-use-__vma_adjust-in-shift_arg_pages.patch mm-mmap-introduce-dup_vma_anon-helper.patch mm-mmap-convert-do_brk_flags-to-use-vma_prepare-and-vma_complete.patch mm-mmap-remove-__vma_adjust.patch vma_merge-set-vma-iterator-to-correct-position.patch