The patch titled
Subject: maple_tree: add mas_next_range() and mas_find_range() interfaces
has been added to the -mm mm-unstable branch. Its filename is
maple_tree-add-mas_next_range-and-mas_find_range-interfaces.patch
This patch will shortly appear at
https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/maple_tree-add-mas_next_range-and-mas_find_range-interfaces.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: maple_tree: add mas_next_range() and mas_find_range() interfaces
Date: Fri, 5 May 2023 13:41:56 -0400
Some users of the maple tree may want to move to the next range in the
tree, even if it stores a NULL. This family of function provides that
functionality by advancing one slot at a time and returning the result,
while mas_contiguous() will iterate over the range and stop on
encountering the first NULL.
Link: https://lkml.kernel.org/r/20230505174204.2665599-29-Liam.Howlett@xxxxxxxxxx
Signed-off-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx>
Cc: David Binderman <dcb314@xxxxxxxxxxx>
Cc: Peng Zhang <zhangpeng.00@xxxxxxxxxxxxx>
Cc: Sergey Senozhatsky <senozhatsky@xxxxxxxxxxxx>
Cc: Wei Yang <richard.weiyang@xxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/maple_tree.h | 15 +++
lib/maple_tree.c | 171 ++++++++++++++++++++++++-----------
2 files changed, 135 insertions(+), 51 deletions(-)
--- a/include/linux/maple_tree.h~maple_tree-add-mas_next_range-and-mas_find_range-interfaces
+++ a/include/linux/maple_tree.h
@@ -455,6 +455,7 @@ void *mas_erase(struct ma_state *mas);
int mas_store_gfp(struct ma_state *mas, void *entry, gfp_t gfp);
void mas_store_prealloc(struct ma_state *mas, void *entry);
void *mas_find(struct ma_state *mas, unsigned long max);
+void *mas_find_range(struct ma_state *mas, unsigned long max);
void *mas_find_rev(struct ma_state *mas, unsigned long min);
int mas_preallocate(struct ma_state *mas, gfp_t gfp);
bool mas_is_err(struct ma_state *mas);
@@ -467,6 +468,7 @@ int mas_expected_entries(struct ma_state
void *mas_prev(struct ma_state *mas, unsigned long min);
void *mas_next(struct ma_state *mas, unsigned long max);
+void *mas_next_range(struct ma_state *mas, unsigned long max);
int mas_empty_area(struct ma_state *mas, unsigned long min, unsigned long max,
unsigned long size);
@@ -528,6 +530,19 @@ static inline void mas_reset(struct ma_s
#define mas_for_each(__mas, __entry, __max) \
while (((__entry) = mas_find((__mas), (__max))) != NULL)
+/**
+ * mas_contiguous() - Iterate over a contiguous range of the maple tree.
+ * @__mas: Maple Tree operation state (maple_state)
+ * @__entry: Entry retrieved from the tree
+ * @__max: maximum index to retrieve from the tree
+ *
+ * When returned, mas->index and mas->last will hold the entire range of the
+ * entry. The loop will terminate on the first NULL encountered.
+ *
+ * Note: may return the zero entry.
+ */
+#define mas_contiguous(__mas, __entry, __max) \
+ while (((__entry) = mas_find_range((__mas), (__max))) != NULL)
/**
* mas_set_range() - Set up Maple Tree operation state for a different index.
--- a/lib/maple_tree.c~maple_tree-add-mas_next_range-and-mas_find_range-interfaces
+++ a/lib/maple_tree.c
@@ -4792,13 +4792,10 @@ again:
*/
static inline void *mas_next_entry(struct ma_state *mas, unsigned long limit)
{
- void *entry = NULL;
-
if (mas->last >= limit)
return NULL;
- entry = mas_next_slot(mas, limit, false);
- return entry;
+ return mas_next_slot(mas, limit, false);
}
/*
@@ -5885,18 +5882,8 @@ int mas_expected_entries(struct ma_state
}
EXPORT_SYMBOL_GPL(mas_expected_entries);
-/**
- * mas_next() - Get the next entry.
- * @mas: The maple state
- * @max: The maximum index to check.
- *
- * Returns the next entry after @mas->index.
- * Must hold rcu_read_lock or the write lock.
- * Can return the zero entry.
- *
- * Return: The next entry or %NULL
- */
-void *mas_next(struct ma_state *mas, unsigned long max)
+static inline bool mas_next_setup(struct ma_state *mas, unsigned long max,
+ void **entry)
{
bool was_none = mas_is_none(mas);
@@ -5904,25 +5891,72 @@ void *mas_next(struct ma_state *mas, uns
mas->node = MAS_START;
if (mas_is_start(mas))
- mas_walk(mas); /* Retries on dead nodes handled by mas_walk */
+ *entry = mas_walk(mas); /* Retries on dead nodes handled by mas_walk */
if (mas_is_ptr(mas)) {
+ *entry = NULL;
if (was_none && mas->index == 0) {
mas->index = mas->last = 0;
- return mas_root(mas);
+ return true;
}
mas->index = 1;
mas->last = ULONG_MAX;
mas->node = MAS_NONE;
- return NULL;
+ return true;
}
- /* Retries on dead nodes handled by mas_next_entry */
- return mas_next_entry(mas, max);
+ if (mas_is_none(mas))
+ return true;
+ return false;
+}
+
+/**
+ * mas_next() - Get the next entry.
+ * @mas: The maple state
+ * @max: The maximum index to check.
+ *
+ * Returns the next entry after @mas->index.
+ * Must hold rcu_read_lock or the write lock.
+ * Can return the zero entry.
+ *
+ * Return: The next entry or %NULL
+ */
+void *mas_next(struct ma_state *mas, unsigned long max)
+{
+ void *entry = NULL;
+
+ if (mas_next_setup(mas, max, &entry))
+ return entry;
+
+ /* Retries on dead nodes handled by mas_next_slot */
+ return mas_next_slot(mas, max, false);
}
EXPORT_SYMBOL_GPL(mas_next);
/**
+ * mas_next_range() - Advance the maple state to the next range
+ * @mas: The maple state
+ * @max: The maximum index to check.
+ *
+ * Sets @mas->index and @mas->last to the range.
+ * Must hold rcu_read_lock or the write lock.
+ * Can return the zero entry.
+ *
+ * Return: The next entry or %NULL
+ */
+void *mas_next_range(struct ma_state *mas, unsigned long max)
+{
+ void *entry = NULL;
+
+ if (mas_next_setup(mas, max, &entry))
+ return entry;
+
+ /* Retries on dead nodes handled by mas_next_slot */
+ return mas_next_slot(mas, max, true);
+}
+EXPORT_SYMBOL_GPL(mas_next_range);
+
+/**
* mt_next() - get the next value in the maple tree
* @mt: The maple tree
* @index: The start index
@@ -6031,49 +6065,38 @@ void mas_pause(struct ma_state *mas)
EXPORT_SYMBOL_GPL(mas_pause);
/**
- * mas_find() - On the first call, find the entry at or after mas->index up to
- * %max. Otherwise, find the entry after mas->index.
- * @mas: The maple state
- * @max: The maximum value to check.
- *
- * Must hold rcu_read_lock or the write lock.
- * If an entry exists, last and index are updated accordingly.
- * May set @mas->node to MAS_NONE.
+ * mas_find_setup() - Internal function to set up mas_find*().
*
- * Return: The entry or %NULL.
+ * Returns: True if entry is the answer, false otherwise.
*/
-void *mas_find(struct ma_state *mas, unsigned long max)
+static inline bool mas_find_setup(struct ma_state *mas, unsigned long max,
+ void **entry)
{
+ *entry = NULL;
+
if (unlikely(mas_is_none(mas))) {
if (unlikely(mas->last >= max))
- return NULL;
+ return true;
mas->index = mas->last;
mas->node = MAS_START;
- }
-
- if (unlikely(mas_is_paused(mas))) {
+ } else if (unlikely(mas_is_paused(mas))) {
if (unlikely(mas->last >= max))
- return NULL;
+ return true;
mas->node = MAS_START;
mas->index = ++mas->last;
- }
-
-
- if (unlikely(mas_is_ptr(mas)))
+ } else if (unlikely(mas_is_ptr(mas)))
goto ptr_out_of_range;
if (unlikely(mas_is_start(mas))) {
/* First run or continue */
- void *entry;
-
if (mas->index > max)
- return NULL;
+ return true;
- entry = mas_walk(mas);
- if (entry)
- return entry;
+ *entry = mas_walk(mas);
+ if (*entry)
+ return true;
}
@@ -6081,24 +6104,70 @@ void *mas_find(struct ma_state *mas, uns
if (unlikely(mas_is_ptr(mas)))
goto ptr_out_of_range;
- return NULL;
+ return true;
}
if (mas->index == max)
- return NULL;
+ return true;
- /* Retries on dead nodes handled by mas_next_slot */
- return mas_next_slot(mas, max, false);
+ return false;
ptr_out_of_range:
mas->node = MAS_NONE;
mas->index = 1;
mas->last = ULONG_MAX;
- return NULL;
+ return true;
+}
+
+/**
+ * mas_find() - On the first call, find the entry at or after mas->index up to
+ * %max. Otherwise, find the entry after mas->index.
+ * @mas: The maple state
+ * @max: The maximum value to check.
+ *
+ * Must hold rcu_read_lock or the write lock.
+ * If an entry exists, last and index are updated accordingly.
+ * May set @mas->node to MAS_NONE.
+ *
+ * Return: The entry or %NULL.
+ */
+void *mas_find(struct ma_state *mas, unsigned long max)
+{
+ void *entry = NULL;
+
+ if (mas_find_setup(mas, max, &entry))
+ return entry;
+
+ /* Retries on dead nodes handled by mas_next_slot */
+ return mas_next_slot(mas, max, false);
}
EXPORT_SYMBOL_GPL(mas_find);
/**
+ * mas_find_range() - On the first call, find the entry at or after
+ * mas->index up to %max. Otherwise, advance to the next slot mas->index.
+ * @mas: The maple state
+ * @max: The maximum value to check.
+ *
+ * Must hold rcu_read_lock or the write lock.
+ * If an entry exists, last and index are updated accordingly.
+ * May set @mas->node to MAS_NONE.
+ *
+ * Return: The entry or %NULL.
+ */
+void *mas_find_range(struct ma_state *mas, unsigned long max)
+{
+ void *entry;
+
+ if (mas_find_setup(mas, max, &entry))
+ return entry;
+
+ /* Retries on dead nodes handled by mas_next_slot */
+ return mas_next_slot(mas, max, true);
+}
+EXPORT_SYMBOL_GPL(mas_find_range);
+
+/**
* mas_find_rev: On the first call, find the first non-null entry at or below
* mas->index down to %min. Otherwise find the first non-null entry below
* mas->index down to %min.
_
Patches currently in -mm which might be from Liam.Howlett@xxxxxxxxxx are
maple_tree-fix-static-analyser-cppcheck-issue.patch
maple_tree-avoid-unnecessary-ascending.patch
maple_tree-clean-up-mas_dfs_postorder.patch
maple_tree-add-debug-bug_on-and-warn_on-variants.patch
maple_tree-use-mas_bug_on-when-setting-a-leaf-node-as-a-parent.patch
maple_tree-use-mas_bug_on-in-mas_set_height.patch
maple_tree-use-mas_bug_on-from-mas_topiary_range.patch
maple_tree-use-mas_wr_bug_on-in-mas_store_prealloc.patch
maple_tree-use-mas_bug_on-prior-to-calling-mas_meta_gap.patch
maple_tree-return-error-on-mte_pivots-out-of-range.patch
maple_tree-make-test-code-work-without-debug-enabled.patch
mm-update-validate_mm-to-use-vma-iterator.patch
mm-update-vma_iter_store-to-use-mas_warn_on.patch
maple_tree-add-__init-and-__exit-to-test-module.patch
maple_tree-remove-unnecessary-check-from-mas_destroy.patch
maple_tree-mas_start-reset-depth-on-dead-node.patch
mm-mmap-change-do_vmi_align_munmap-for-maple-tree-iterator-changes.patch
maple_tree-try-harder-to-keep-active-node-after-mas_next.patch
maple_tree-try-harder-to-keep-active-node-with-mas_prev.patch
maple_tree-revise-limit-checks-in-mas_empty_area_rev.patch
maple_tree-fix-testing-mas_empty_area.patch
maple_tree-introduce-mas_next_slot-interface.patch
maple_tree-add-mas_next_range-and-mas_find_range-interfaces.patch
maple_tree-relocate-mas_rewalk-and-mas_rewalk_if_dead.patch
maple_tree-introduce-mas_prev_slot-interface.patch
maple_tree-add-mas_prev_range-and-mas_find_range_rev-interface.patch
maple_tree-clear-up-index-and-last-setting-in-single-entry-tree.patch
maple_tree-update-testing-code-for-mas_nextprevwalk.patch
mm-add-vma_iter_nextprev_range-to-vma-iterator.patch
mm-avoid-rewalk-in-mmap_region.patch
maple_tree-add-gap-to-check_alloc_rev_range-testcase.patch
