The patch titled
Subject: mm: use maple tree operations for find_vma_intersection()
has been added to the -mm mm-unstable branch. Its filename is
mm-use-maple-tree-operations-for-find_vma_intersection.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-use-maple-tree-operations-for-find_vma_intersection.patch
This patch will later appear in the mm-unstable branch at
git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------
From: "Liam R. Howlett" <Liam.Howlett@xxxxxxxxxx>
Subject: mm: use maple tree operations for find_vma_intersection()
Date: Mon, 22 Aug 2022 15:05:06 +0000
Move find_vma_intersection() to mmap.c and change implementation to maple
tree.
When searching for a vma within a range, it is easier to use the maple
tree interface.
Exported find_vma_intersection() for kvm module.
Link: https://lkml.kernel.org/r/20220822150128.1562046-24-Liam.Howlett@xxxxxxxxxx
Signed-off-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx>
Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: David Hildenbrand <david@xxxxxxxxxx>
Cc: David Howells <dhowells@xxxxxxxxxx>
Cc: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx>
Cc: SeongJae Park <sj@xxxxxxxxxx>
Cc: Sven Schnelle <svens@xxxxxxxxxxxxx>
Cc: Vlastimil Babka <vbabka@xxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
Cc: Yu Zhao <yuzhao@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/mm.h | 22 ++++------------------
mm/mmap.c | 29 +++++++++++++++++++++++++++++
mm/nommu.c | 11 +++++++++++
3 files changed, 44 insertions(+), 18 deletions(-)
--- a/include/linux/mm.h~mm-use-maple-tree-operations-for-find_vma_intersection
+++ a/include/linux/mm.h
@@ -2782,26 +2782,12 @@ extern struct vm_area_struct * find_vma(
extern struct vm_area_struct * find_vma_prev(struct mm_struct * mm, unsigned long addr,
struct vm_area_struct **pprev);
-/**
- * find_vma_intersection() - Look up the first VMA which intersects the interval
- * @mm: The process address space.
- * @start_addr: The inclusive start user address.
- * @end_addr: The exclusive end user address.
- *
- * Returns: The first VMA within the provided range, %NULL otherwise. Assumes
- * start_addr < end_addr.
+/*
+ * Look up the first VMA which intersects the interval [start_addr, end_addr)
+ * NULL if none. Assume start_addr < end_addr.
*/
-static inline
struct vm_area_struct *find_vma_intersection(struct mm_struct *mm,
- unsigned long start_addr,
- unsigned long end_addr)
-{
- struct vm_area_struct *vma = find_vma(mm, start_addr);
-
- if (vma && end_addr <= vma->vm_start)
- vma = NULL;
- return vma;
-}
+ unsigned long start_addr, unsigned long end_addr);
/**
* vma_lookup() - Find a VMA at a specific address
--- a/mm/mmap.c~mm-use-maple-tree-operations-for-find_vma_intersection
+++ a/mm/mmap.c
@@ -2062,6 +2062,35 @@ get_unmapped_area(struct file *file, uns
EXPORT_SYMBOL(get_unmapped_area);
/**
+ * find_vma_intersection() - Look up the first VMA which intersects the interval
+ * @mm: The process address space.
+ * @start_addr: The inclusive start user address.
+ * @end_addr: The exclusive end user address.
+ *
+ * Returns: The first VMA within the provided range, %NULL otherwise. Assumes
+ * start_addr < end_addr.
+ */
+struct vm_area_struct *find_vma_intersection(struct mm_struct *mm,
+ unsigned long start_addr,
+ unsigned long end_addr)
+{
+ struct vm_area_struct *vma;
+ unsigned long index = start_addr;
+
+ mmap_assert_locked(mm);
+ /* Check the cache first. */
+ vma = vmacache_find(mm, start_addr);
+ if (likely(vma))
+ return vma;
+
+ vma = mt_find(&mm->mm_mt, &index, end_addr - 1);
+ if (vma)
+ vmacache_update(start_addr, vma);
+ return vma;
+}
+EXPORT_SYMBOL(find_vma_intersection);
+
+/**
* find_vma() - Find the VMA for a given address, or the next VMA.
* @mm: The mm_struct to check
* @addr: The address
--- a/mm/nommu.c~mm-use-maple-tree-operations-for-find_vma_intersection
+++ a/mm/nommu.c
@@ -642,6 +642,17 @@ static void delete_vma(struct mm_struct
vm_area_free(vma);
}
+struct vm_area_struct *find_vma_intersection(struct mm_struct *mm,
+ unsigned long start_addr,
+ unsigned long end_addr)
+{
+ unsigned long index = start_addr;
+
+ mmap_assert_locked(mm);
+ return mt_find(&mm->mm_mt, &index, end_addr - 1);
+}
+EXPORT_SYMBOL(find_vma_intersection);
+
/*
* look up the first VMA in which addr resides, NULL if none
* - should be called with mm->mmap_lock at least held readlocked
_
Patches currently in -mm which might be from Liam.Howlett@xxxxxxxxxx are
maple-tree-add-new-data-structure.patch
radix-tree-test-suite-add-pr_err-define.patch
radix-tree-test-suite-add-kmem_cache_set_non_kernel.patch
radix-tree-test-suite-add-allocation-counts-and-size-to-kmem_cache.patch
radix-tree-test-suite-add-support-for-slab-bulk-apis.patch
radix-tree-test-suite-add-lockdep_is_held-to-header.patch
lib-test_maple_tree-add-testing-for-maple-tree.patch
mm-start-tracking-vmas-with-maple-tree.patch
mm-mmap-use-the-maple-tree-in-find_vma-instead-of-the-rbtree.patch
mm-mmap-use-the-maple-tree-for-find_vma_prev-instead-of-the-rbtree.patch
mm-mmap-use-maple-tree-for-unmapped_area_topdown.patch
kernel-fork-use-maple-tree-for-dup_mmap-during-forking.patch
damon-convert-__damon_va_three_regions-to-use-the-vma-iterator.patch
mm-remove-rb-tree.patch
mmap-change-zeroing-of-maple-tree-in-__vma_adjust.patch
xen-use-vma_lookup-in-privcmd_ioctl_mmap.patch
mm-optimize-find_exact_vma-to-use-vma_lookup.patch
mm-khugepaged-optimize-collapse_pte_mapped_thp-by-using-vma_lookup.patch
mm-mmap-change-do_brk_flags-to-expand-existing-vma-and-add-do_brk_munmap.patch
mm-use-maple-tree-operations-for-find_vma_intersection.patch
mm-mmap-use-advanced-maple-tree-api-for-mmap_region.patch
mm-remove-vmacache.patch
mm-convert-vma_lookup-to-use-mtree_load.patch
mm-mmap-move-mmap_region-below-do_munmap.patch
mm-mmap-reorganize-munmap-to-use-maple-states.patch
mm-mmap-change-do_brk_munmap-to-use-do_mas_align_munmap.patch
arm64-change-elfcore-for_each_mte_vma-to-use-vma-iterator.patch
fs-proc-base-use-maple-tree-iterators-in-place-of-linked-list.patch
userfaultfd-use-maple-tree-iterator-to-iterate-vmas.patch
ipc-shm-use-vma-iterator-instead-of-linked-list.patch
bpf-remove-vma-linked-list.patch
mm-gup-use-maple-tree-navigation-instead-of-linked-list.patch
mm-madvise-use-vma_find-instead-of-vma-linked-list.patch
mm-memcontrol-stop-using-mm-highest_vm_end.patch
mm-mempolicy-use-vma-iterator-maple-state-instead-of-vma-linked-list.patch
mm-mprotect-use-maple-tree-navigation-instead-of-vma-linked-list.patch
mm-mremap-use-vma_find_intersection-instead-of-vma-linked-list.patch
mm-msync-use-vma_find-instead-of-vma-linked-list.patch
mm-oom_kill-use-maple-tree-iterators-instead-of-vma-linked-list.patch
mm-swapfile-use-vma-iterator-instead-of-vma-linked-list.patch
riscv-use-vma-iterator-for-vdso.patch
mm-remove-the-vma-linked-list.patch
mm-mmap-drop-range_has_overlap-function.patch
mm-mmapc-pass-in-mapping-to-__vma_link_file.patch
