The patch titled
Subject: mm: expand vma iterator interface
has been added to the -mm mm-unstable branch. Its filename is
mm-expand-vma-iterator-interface.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mm-expand-vma-iterator-interface.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: expand vma iterator interface
Date: Fri, 20 Jan 2023 11:26:08 -0500
Add wrappers for the maple tree to the vma iterator. This will provide
type safety at compile time.
Link: https://lkml.kernel.org/r/20230120162650.984577-8-Liam.Howlett@xxxxxxxxxx
Signed-off-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
--- a/include/linux/mm.h~mm-expand-vma-iterator-interface
+++ a/include/linux/mm.h
@@ -670,16 +670,16 @@ static inline bool vma_is_accessible(str
static inline
struct vm_area_struct *vma_find(struct vma_iterator *vmi, unsigned long max)
{
- return mas_find(&vmi->mas, max);
+ return mas_find(&vmi->mas, max - 1);
}
static inline struct vm_area_struct *vma_next(struct vma_iterator *vmi)
{
/*
- * Uses vma_find() to get the first VMA when the iterator starts.
+ * Uses mas_find() to get the first VMA when the iterator starts.
* Calling mas_next() could skip the first entry.
*/
- return vma_find(vmi, ULONG_MAX);
+ return mas_find(&vmi->mas, ULONG_MAX);
}
static inline struct vm_area_struct *vma_prev(struct vma_iterator *vmi)
@@ -692,12 +692,50 @@ static inline unsigned long vma_iter_add
return vmi->mas.index;
}
+static inline unsigned long vma_iter_end(struct vma_iterator *vmi)
+{
+ return vmi->mas.last + 1;
+}
+static inline int vma_iter_bulk_alloc(struct vma_iterator *vmi,
+ unsigned long count)
+{
+ return mas_expected_entries(&vmi->mas, count);
+}
+
+/* Free any unused preallocations */
+static inline void vma_iter_free(struct vma_iterator *vmi)
+{
+ mas_destroy(&vmi->mas);
+}
+
+static inline int vma_iter_bulk_store(struct vma_iterator *vmi,
+ struct vm_area_struct *vma)
+{
+ vmi->mas.index = vma->vm_start;
+ vmi->mas.last = vma->vm_end - 1;
+ mas_store(&vmi->mas, vma);
+ if (unlikely(mas_is_err(&vmi->mas)))
+ return -ENOMEM;
+
+ return 0;
+}
+
+static inline void vma_iter_invalidate(struct vma_iterator *vmi)
+{
+ mas_pause(&vmi->mas);
+}
+
+static inline void vma_iter_set(struct vma_iterator *vmi, unsigned long addr)
+{
+ mas_set(&vmi->mas, addr);
+}
+
#define for_each_vma(__vmi, __vma) \
while (((__vma) = vma_next(&(__vmi))) != NULL)
/* The MM code likes to work with exclusive end addresses */
#define for_each_vma_range(__vmi, __vma, __end) \
- while (((__vma) = vma_find(&(__vmi), (__end) - 1)) != NULL)
+ while (((__vma) = vma_find(&(__vmi), (__end))) != NULL)
#ifdef CONFIG_SHMEM
/*
--- a/include/linux/mm_types.h~mm-expand-vma-iterator-interface
+++ a/include/linux/mm_types.h
@@ -854,9 +854,7 @@ struct vma_iterator {
static inline void vma_iter_init(struct vma_iterator *vmi,
struct mm_struct *mm, unsigned long addr)
{
- vmi->mas.tree = &mm->mm_mt;
- vmi->mas.index = addr;
- vmi->mas.node = MAS_START;
+ mas_init(&vmi->mas, &mm->mm_mt, addr);
}
struct mmu_gather;
--- a/mm/internal.h~mm-expand-vma-iterator-interface
+++ a/mm/internal.h
@@ -873,4 +873,68 @@ static inline bool vma_soft_dirty_enable
return !(vma->vm_flags & VM_SOFTDIRTY);
}
+/*
+ * VMA Iterator functions shared between nommu and mmap
+ */
+static inline int vma_iter_prealloc(struct vma_iterator *vmi)
+{
+ return mas_preallocate(&vmi->mas, GFP_KERNEL);
+}
+
+static inline void vma_iter_clear(struct vma_iterator *vmi,
+ unsigned long start, unsigned long end)
+{
+ mas_set_range(&vmi->mas, start, end - 1);
+ mas_store_prealloc(&vmi->mas, NULL);
+}
+
+static inline struct vm_area_struct *vma_iter_load(struct vma_iterator *vmi)
+{
+ return mas_walk(&vmi->mas);
+}
+
+/* Store a VMA with preallocated memory */
+static inline void vma_iter_store(struct vma_iterator *vmi,
+ struct vm_area_struct *vma)
+{
+
+#if defined(CONFIG_DEBUG_VM_MAPLE_TREE)
+ if (WARN_ON(vmi->mas.node != MAS_START && vmi->mas.index > vma->vm_start)) {
+ printk("%lu > %lu\n", vmi->mas.index, vma->vm_start);
+ printk("store of vma %lu-%lu", vma->vm_start, vma->vm_end);
+ printk("into slot %lu-%lu", vmi->mas.index, vmi->mas.last);
+ mt_dump(vmi->mas.tree);
+ }
+ if (WARN_ON(vmi->mas.node != MAS_START && vmi->mas.last < vma->vm_start)) {
+ printk("%lu < %lu\n", vmi->mas.last, vma->vm_start);
+ printk("store of vma %lu-%lu", vma->vm_start, vma->vm_end);
+ printk("into slot %lu-%lu", vmi->mas.index, vmi->mas.last);
+ mt_dump(vmi->mas.tree);
+ }
+#endif
+
+ if (vmi->mas.node != MAS_START &&
+ ((vmi->mas.index > vma->vm_start) || (vmi->mas.last < vma->vm_start)))
+ vma_iter_invalidate(vmi);
+
+ vmi->mas.index = vma->vm_start;
+ vmi->mas.last = vma->vm_end - 1;
+ mas_store_prealloc(&vmi->mas, vma);
+}
+
+static inline int vma_iter_store_gfp(struct vma_iterator *vmi,
+ struct vm_area_struct *vma, gfp_t gfp)
+{
+ if (vmi->mas.node != MAS_START &&
+ ((vmi->mas.index > vma->vm_start) || (vmi->mas.last < vma->vm_start)))
+ vma_iter_invalidate(vmi);
+
+ vmi->mas.index = vma->vm_start;
+ vmi->mas.last = vma->vm_end - 1;
+ mas_store_gfp(&vmi->mas, vma, gfp);
+ if (unlikely(mas_is_err(&vmi->mas)))
+ return -ENOMEM;
+
+ return 0;
+}
#endif /* __MM_INTERNAL_H */
--- a/mm/mmap.c~mm-expand-vma-iterator-interface
+++ a/mm/mmap.c
@@ -144,6 +144,24 @@ static void remove_vma(struct vm_area_st
vm_area_free(vma);
}
+static inline struct vm_area_struct *vma_prev_limit(struct vma_iterator *vmi,
+ unsigned long min)
+{
+ return mas_prev(&vmi->mas, min);
+}
+
+static inline int vma_iter_clear_gfp(struct vma_iterator *vmi,
+ unsigned long start, unsigned long end, gfp_t gfp)
+{
+ vmi->mas.index = start;
+ vmi->mas.last = end - 1;
+ mas_store_gfp(&vmi->mas, NULL, gfp);
+ if (unlikely(mas_is_err(&vmi->mas)))
+ return -ENOMEM;
+
+ return 0;
+}
+
/*
* check_brk_limits() - Use platform specific check of range & verify mlock
* limits.
_
Patches currently in -mm which might be from Liam.Howlett@xxxxxxxxxx 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
