#include <linux/rcupdate.h>
#include <linux/slab.h>
#include <linux/string.h>
+#include <linux/xarray.h>
-/* Number of nodes in fully populated tree of given height */
-static unsigned long height_to_maxnodes[RADIX_TREE_MAX_PATH + 1] __read_mostly;
-
/*
* Radix tree node cache.
*/
-static struct kmem_cache *radix_tree_node_cachep;
+struct kmem_cache *radix_tree_node_cachep;
/*
* The radix tree is variable-height, so an insert operation not only has
return (void *)((unsigned long)ptr | RADIX_TREE_INTERNAL_NODE);
}
-#define RADIX_TREE_RETRY node_to_entry(NULL)
-
-#ifdef CONFIG_RADIX_TREE_MULTIORDER
-/* Sibling slots point directly to another slot in the same node */
-static inline
-bool is_sibling_entry(const struct radix_tree_node *parent, void *node)
-{
- void __rcu **ptr = node;
- return (parent->slots <= ptr) &&
- (ptr < parent->slots + RADIX_TREE_MAP_SIZE);
-}
-#else
-static inline
-bool is_sibling_entry(const struct radix_tree_node *parent, void *node)
-{
- return false;
-}
-#endif
+#define RADIX_TREE_RETRY XA_RETRY_ENTRY
static inline unsigned long
get_slot_offset(const struct radix_tree_node *parent, void __rcu **slot)
unsigned int offset = (index >> parent->shift) & RADIX_TREE_MAP_MASK;
void __rcu **entry = rcu_dereference_raw(parent->slots[offset]);
-#ifdef CONFIG_RADIX_TREE_MULTIORDER
- if (radix_tree_is_internal_node(entry)) {
- if (is_sibling_entry(parent, entry)) {
- void __rcu **sibentry;
- sibentry = (void __rcu **) entry_to_node(entry);
- offset = get_slot_offset(parent, sibentry);
- entry = rcu_dereference_raw(*sibentry);
- }
- }
-#endif
-
*nodep = (void *)entry;
return offset;
}
static inline gfp_t root_gfp_mask(const struct radix_tree_root *root)
{
- return root->gfp_mask & (__GFP_BITS_MASK & ~GFP_ZONEMASK);
+ return root->xa_flags & (__GFP_BITS_MASK & ~GFP_ZONEMASK);
}
static inline void tag_set(struct radix_tree_node *node, unsigned int tag,
static inline void root_tag_set(struct radix_tree_root *root, unsigned tag)
{
- root->gfp_mask |= (__force gfp_t)(1 << (tag + ROOT_TAG_SHIFT));
+ root->xa_flags |= (__force gfp_t)(1 << (tag + ROOT_TAG_SHIFT));
}
static inline void root_tag_clear(struct radix_tree_root *root, unsigned tag)
{
- root->gfp_mask &= (__force gfp_t)~(1 << (tag + ROOT_TAG_SHIFT));
+ root->xa_flags &= (__force gfp_t)~(1 << (tag + ROOT_TAG_SHIFT));
}
static inline void root_tag_clear_all(struct radix_tree_root *root)
{
- root->gfp_mask &= (1 << ROOT_TAG_SHIFT) - 1;
+ root->xa_flags &= (__force gfp_t)((1 << ROOT_TAG_SHIFT) - 1);
}
static inline int root_tag_get(const struct radix_tree_root *root, unsigned tag)
{
- return (__force int)root->gfp_mask & (1 << (tag + ROOT_TAG_SHIFT));
+ return (__force int)root->xa_flags & (1 << (tag + ROOT_TAG_SHIFT));
}
static inline unsigned root_tags_get(const struct radix_tree_root *root)
{
- return (__force unsigned)root->gfp_mask >> ROOT_TAG_SHIFT;
+ return (__force unsigned)root->xa_flags >> ROOT_TAG_SHIFT;
}
static inline bool is_idr(const struct radix_tree_root *root)
{
- return !!(root->gfp_mask & ROOT_IS_IDR);
+ return !!(root->xa_flags & ROOT_IS_IDR);
}
/*
static unsigned int iter_offset(const struct radix_tree_iter *iter)
{
- return (iter->index >> iter_shift(iter)) & RADIX_TREE_MAP_MASK;
+ return iter->index & RADIX_TREE_MAP_MASK;
}
/*
return (index & ~node_maxindex(node)) + (offset << node->shift);
}
-#ifndef __KERNEL__
-static void dump_node(struct radix_tree_node *node, unsigned long index)
-{
- unsigned long i;
-
- pr_debug("radix node: %p offset %d indices %lu-%lu parent %p tags %lx %lx %lx shift %d count %d exceptional %d\n",
- node, node->offset, index, index | node_maxindex(node),
- node->parent,
- node->tags[0][0], node->tags[1][0], node->tags[2][0],
- node->shift, node->count, node->exceptional);
-
- for (i = 0; i < RADIX_TREE_MAP_SIZE; i++) {
- unsigned long first = index | (i << node->shift);
- unsigned long last = first | ((1UL << node->shift) - 1);
- void *entry = node->slots[i];
- if (!entry)
- continue;
- if (entry == RADIX_TREE_RETRY) {
- pr_debug("radix retry offset %ld indices %lu-%lu parent %p\n",
- i, first, last, node);
- } else if (!radix_tree_is_internal_node(entry)) {
- pr_debug("radix entry %p offset %ld indices %lu-%lu parent %p\n",
- entry, i, first, last, node);
- } else if (is_sibling_entry(node, entry)) {
- pr_debug("radix sblng %p offset %ld indices %lu-%lu parent %p val %p\n",
- entry, i, first, last, node,
- *(void **)entry_to_node(entry));
- } else {
- dump_node(entry_to_node(entry), first);
- }
- }
-}
-
-/* For debug */
-static void radix_tree_dump(struct radix_tree_root *root)
-{
- pr_debug("radix root: %p rnode %p tags %x\n",
- root, root->rnode,
- root->gfp_mask >> ROOT_TAG_SHIFT);
- if (!radix_tree_is_internal_node(root->rnode))
- return;
- dump_node(entry_to_node(root->rnode), 0);
-}
-
-static void dump_ida_node(void *entry, unsigned long index)
-{
- unsigned long i;
-
- if (!entry)
- return;
-
- if (radix_tree_is_internal_node(entry)) {
- struct radix_tree_node *node = entry_to_node(entry);
-
- pr_debug("ida node: %p offset %d indices %lu-%lu parent %p free %lx shift %d count %d\n",
- node, node->offset, index * IDA_BITMAP_BITS,
- ((index | node_maxindex(node)) + 1) *
- IDA_BITMAP_BITS - 1,
- node->parent, node->tags[0][0], node->shift,
- node->count);
- for (i = 0; i < RADIX_TREE_MAP_SIZE; i++)
- dump_ida_node(node->slots[i],
- index | (i << node->shift));
- } else if (radix_tree_exceptional_entry(entry)) {
- pr_debug("ida excp: %p offset %d indices %lu-%lu data %lx\n",
- entry, (int)(index & RADIX_TREE_MAP_MASK),
- index * IDA_BITMAP_BITS,
- index * IDA_BITMAP_BITS + BITS_PER_LONG -
- RADIX_TREE_EXCEPTIONAL_SHIFT,
- (unsigned long)entry >>
- RADIX_TREE_EXCEPTIONAL_SHIFT);
- } else {
- struct ida_bitmap *bitmap = entry;
-
- pr_debug("ida btmp: %p offset %d indices %lu-%lu data", bitmap,
- (int)(index & RADIX_TREE_MAP_MASK),
- index * IDA_BITMAP_BITS,
- (index + 1) * IDA_BITMAP_BITS - 1);
- for (i = 0; i < IDA_BITMAP_LONGS; i++)
- pr_cont(" %lx", bitmap->bitmap[i]);
- pr_cont("\n");
- }
-}
-
-static void ida_dump(struct ida *ida)
-{
- struct radix_tree_root *root = &ida->ida_rt;
- pr_debug("ida: %p node %p free %d\n", ida, root->rnode,
- root->gfp_mask >> ROOT_TAG_SHIFT);
- dump_ida_node(root->rnode, 0);
-}
-#endif
-
/*
* This assumes that the caller has performed appropriate preallocation, and
* that the caller has pinned this thread of control to the current CPU.
radix_tree_node_alloc(gfp_t gfp_mask, struct radix_tree_node *parent,
struct radix_tree_root *root,
unsigned int shift, unsigned int offset,
- unsigned int count, unsigned int exceptional)
+ unsigned int count, unsigned int nr_values)
{
struct radix_tree_node *ret = NULL;
ret->shift = shift;
ret->offset = offset;
ret->count = count;
- ret->exceptional = exceptional;
+ ret->nr_values = nr_values;
ret->parent = parent;
- ret->root = root;
+ ret->array = root;
}
return ret;
}
-static void radix_tree_node_rcu_free(struct rcu_head *head)
+void radix_tree_node_rcu_free(struct rcu_head *head)
{
struct radix_tree_node *node =
container_of(head, struct radix_tree_node, rcu_head);
}
EXPORT_SYMBOL(radix_tree_maybe_preload);
-#ifdef CONFIG_RADIX_TREE_MULTIORDER
-/*
- * Preload with enough objects to ensure that we can split a single entry
- * of order @old_order into many entries of size @new_order
- */
-int radix_tree_split_preload(unsigned int old_order, unsigned int new_order,
- gfp_t gfp_mask)
-{
- unsigned top = 1 << (old_order % RADIX_TREE_MAP_SHIFT);
- unsigned layers = (old_order / RADIX_TREE_MAP_SHIFT) -
- (new_order / RADIX_TREE_MAP_SHIFT);
- unsigned nr = 0;
-
- WARN_ON_ONCE(!gfpflags_allow_blocking(gfp_mask));
- BUG_ON(new_order >= old_order);
-
- while (layers--)
- nr = nr * RADIX_TREE_MAP_SIZE + 1;
- return __radix_tree_preload(gfp_mask, top * nr);
-}
-#endif
-
-/*
- * The same as function above, but preload number of nodes required to insert
- * (1 << order) continuous naturally-aligned elements.
- */
-int radix_tree_maybe_preload_order(gfp_t gfp_mask, int order)
-{
- unsigned long nr_subtrees;
- int nr_nodes, subtree_height;
-
- /* Preloading doesn't help anything with this gfp mask, skip it */
- if (!gfpflags_allow_blocking(gfp_mask)) {
- preempt_disable();
- return 0;
- }
-
- /*
- * Calculate number and height of fully populated subtrees it takes to
- * store (1 << order) elements.
- */
- nr_subtrees = 1 << order;
- for (subtree_height = 0; nr_subtrees > RADIX_TREE_MAP_SIZE;
- subtree_height++)
- nr_subtrees >>= RADIX_TREE_MAP_SHIFT;
-
- /*
- * The worst case is zero height tree with a single item at index 0 and
- * then inserting items starting at ULONG_MAX - (1 << order).
- *
- * This requires RADIX_TREE_MAX_PATH nodes to build branch from root to
- * 0-index item.
- */
- nr_nodes = RADIX_TREE_MAX_PATH;
-
- /* Plus branch to fully populated subtrees. */
- nr_nodes += RADIX_TREE_MAX_PATH - subtree_height;
-
- /* Root node is shared. */
- nr_nodes--;
-
- /* Plus nodes required to build subtrees. */
- nr_nodes += nr_subtrees * height_to_maxnodes[subtree_height];
-
- return __radix_tree_preload(gfp_mask, nr_nodes);
-}
-
static unsigned radix_tree_load_root(const struct radix_tree_root *root,
struct radix_tree_node **nodep, unsigned long *maxindex)
{
- struct radix_tree_node *node = rcu_dereference_raw(root->rnode);
+ struct radix_tree_node *node = rcu_dereference_raw(root->xa_head);
*nodep = node;
while (index > shift_maxindex(maxshift))
maxshift += RADIX_TREE_MAP_SHIFT;
- entry = rcu_dereference_raw(root->rnode);
+ entry = rcu_dereference_raw(root->xa_head);
if (!entry && (!is_idr(root) || root_tag_get(root, IDR_FREE)))
goto out;
BUG_ON(shift > BITS_PER_LONG);
if (radix_tree_is_internal_node(entry)) {
entry_to_node(entry)->parent = node;
- } else if (radix_tree_exceptional_entry(entry)) {
- /* Moving an exceptional root->rnode to a node */
- node->exceptional = 1;
+ } else if (xa_is_value(entry)) {
+ /* Moving a value entry root->xa_head to a node */
+ node->nr_values = 1;
}
/*
* entry was already in the radix tree, so we do not need
*/
node->slots[0] = (void __rcu *)entry;
entry = node_to_entry(node);
- rcu_assign_pointer(root->rnode, entry);
+ rcu_assign_pointer(root->xa_head, entry);
shift += RADIX_TREE_MAP_SHIFT;
} while (shift <= maxshift);
out:
* radix_tree_shrink - shrink radix tree to minimum height
* @root radix tree root
*/
-static inline bool radix_tree_shrink(struct radix_tree_root *root,
- radix_tree_update_node_t update_node)
+static inline bool radix_tree_shrink(struct radix_tree_root *root)
{
bool shrunk = false;
for (;;) {
- struct radix_tree_node *node = rcu_dereference_raw(root->rnode);
+ struct radix_tree_node *node = rcu_dereference_raw(root->xa_head);
struct radix_tree_node *child;
if (!radix_tree_is_internal_node(node))
/*
* The candidate node has more than one child, or its child
- * is not at the leftmost slot, or the child is a multiorder
- * entry, we cannot shrink.
+ * is not at the leftmost slot, we cannot shrink.
*/
if (node->count != 1)
break;
child = rcu_dereference_raw(node->slots[0]);
if (!child)
break;
- if (!radix_tree_is_internal_node(child) && node->shift)
+
+ /*
+ * For an IDR, we must not shrink entry 0 into the root in
+ * case somebody calls idr_replace() with a pointer that
+ * appears to be an internal entry
+ */
+ if (!node->shift && is_idr(root))
break;
if (radix_tree_is_internal_node(child))
* moving the node from one part of the tree to another: if it
* was safe to dereference the old pointer to it
* (node->slots[0]), it will be safe to dereference the new
- * one (root->rnode) as far as dependent read barriers go.
+ * one (root->xa_head) as far as dependent read barriers go.
*/
- root->rnode = (void __rcu *)child;
+ root->xa_head = (void __rcu *)child;
if (is_idr(root) && !tag_get(node, IDR_FREE, 0))
root_tag_clear(root, IDR_FREE);
node->count = 0;
if (!radix_tree_is_internal_node(child)) {
node->slots[0] = (void __rcu *)RADIX_TREE_RETRY;
- if (update_node)
- update_node(node);
}
WARN_ON_ONCE(!list_empty(&node->private_list));
}
static bool delete_node(struct radix_tree_root *root,
- struct radix_tree_node *node,
- radix_tree_update_node_t update_node)
+ struct radix_tree_node *node)
{
bool deleted = false;
if (node->count) {
if (node_to_entry(node) ==
- rcu_dereference_raw(root->rnode))
- deleted |= radix_tree_shrink(root,
- update_node);
+ rcu_dereference_raw(root->xa_head))
+ deleted |= radix_tree_shrink(root);
return deleted;
}
*/
if (!is_idr(root))
root_tag_clear_all(root);
- root->rnode = NULL;
+ root->xa_head = NULL;
}
WARN_ON_ONCE(!list_empty(&node->private_list));
* __radix_tree_create - create a slot in a radix tree
* @root: radix tree root
* @index: index key
- * @order: index occupies 2^order aligned slots
* @nodep: returns node
* @slotp: returns slot
*
* at position @index in the radix tree @root.
*
* Until there is more than one item in the tree, no nodes are
- * allocated and @root->rnode is used as a direct slot instead of
+ * allocated and @root->xa_head is used as a direct slot instead of
* pointing to a node, in which case *@nodep will be NULL.
*
* Returns -ENOMEM, or 0 for success.
*/
-int __radix_tree_create(struct radix_tree_root *root, unsigned long index,
- unsigned order, struct radix_tree_node **nodep,
- void __rcu ***slotp)
+static int __radix_tree_create(struct radix_tree_root *root,
+ unsigned long index, struct radix_tree_node **nodep,
+ void __rcu ***slotp)
{
struct radix_tree_node *node = NULL, *child;
- void __rcu **slot = (void __rcu **)&root->rnode;
+ void __rcu **slot = (void __rcu **)&root->xa_head;
unsigned long maxindex;
unsigned int shift, offset = 0;
- unsigned long max = index | ((1UL << order) - 1);
+ unsigned long max = index;
gfp_t gfp = root_gfp_mask(root);
shift = radix_tree_load_root(root, &child, &maxindex);
/* Make sure the tree is high enough. */
- if (order > 0 && max == ((1UL << order) - 1))
- max++;
if (max > maxindex) {
int error = radix_tree_extend(root, gfp, max, shift);
if (error < 0)
return error;
shift = error;
- child = rcu_dereference_raw(root->rnode);
+ child = rcu_dereference_raw(root->xa_head);
}
- while (shift > order) {
+ while (shift > 0) {
shift -= RADIX_TREE_MAP_SHIFT;
if (child == NULL) {
/* Have to add a child node. */
for (;;) {
void *entry = rcu_dereference_raw(child->slots[offset]);
- if (radix_tree_is_internal_node(entry) &&
- !is_sibling_entry(child, entry)) {
+ if (xa_is_node(entry) && child->shift) {
child = entry_to_node(entry);
offset = 0;
continue;
}
}
-#ifdef CONFIG_RADIX_TREE_MULTIORDER
static inline int insert_entries(struct radix_tree_node *node,
- void __rcu **slot, void *item, unsigned order, bool replace)
-{
- struct radix_tree_node *child;
- unsigned i, n, tag, offset, tags = 0;
-
- if (node) {
- if (order > node->shift)
- n = 1 << (order - node->shift);
- else
- n = 1;
- offset = get_slot_offset(node, slot);
- } else {
- n = 1;
- offset = 0;
- }
-
- if (n > 1) {
- offset = offset & ~(n - 1);
- slot = &node->slots[offset];
- }
- child = node_to_entry(slot);
-
- for (i = 0; i < n; i++) {
- if (slot[i]) {
- if (replace) {
- node->count--;
- for (tag = 0; tag < RADIX_TREE_MAX_TAGS; tag++)
- if (tag_get(node, tag, offset + i))
- tags |= 1 << tag;
- } else
- return -EEXIST;
- }
- }
-
- for (i = 0; i < n; i++) {
- struct radix_tree_node *old = rcu_dereference_raw(slot[i]);
- if (i) {
- rcu_assign_pointer(slot[i], child);
- for (tag = 0; tag < RADIX_TREE_MAX_TAGS; tag++)
- if (tags & (1 << tag))
- tag_clear(node, tag, offset + i);
- } else {
- rcu_assign_pointer(slot[i], item);
- for (tag = 0; tag < RADIX_TREE_MAX_TAGS; tag++)
- if (tags & (1 << tag))
- tag_set(node, tag, offset);
- }
- if (radix_tree_is_internal_node(old) &&
- !is_sibling_entry(node, old) &&
- (old != RADIX_TREE_RETRY))
- radix_tree_free_nodes(old);
- if (radix_tree_exceptional_entry(old))
- node->exceptional--;
- }
- if (node) {
- node->count += n;
- if (radix_tree_exceptional_entry(item))
- node->exceptional += n;
- }
- return n;
-}
-#else
-static inline int insert_entries(struct radix_tree_node *node,
- void __rcu **slot, void *item, unsigned order, bool replace)
+ void __rcu **slot, void *item, bool replace)
{
if (*slot)
return -EEXIST;
rcu_assign_pointer(*slot, item);
if (node) {
node->count++;
- if (radix_tree_exceptional_entry(item))
- node->exceptional++;
+ if (xa_is_value(item))
+ node->nr_values++;
}
return 1;
}
-#endif
/**
* __radix_tree_insert - insert into a radix tree
* @root: radix tree root
* @index: index key
- * @order: key covers the 2^order indices around index
* @item: item to insert
*
* Insert an item into the radix tree at position @index.
*/
-int __radix_tree_insert(struct radix_tree_root *root, unsigned long index,
- unsigned order, void *item)
+int radix_tree_insert(struct radix_tree_root *root, unsigned long index,
+ void *item)
{
struct radix_tree_node *node;
void __rcu **slot;
BUG_ON(radix_tree_is_internal_node(item));
- error = __radix_tree_create(root, index, order, &node, &slot);
+ error = __radix_tree_create(root, index, &node, &slot);
if (error)
return error;
- error = insert_entries(node, slot, item, order, false);
+ error = insert_entries(node, slot, item, false);
if (error < 0)
return error;
return 0;
}
-EXPORT_SYMBOL(__radix_tree_insert);
+EXPORT_SYMBOL(radix_tree_insert);
/**
* __radix_tree_lookup - lookup an item in a radix tree
* tree @root.
*
* Until there is more than one item in the tree, no nodes are
- * allocated and @root->rnode is used as a direct slot instead of
+ * allocated and @root->xa_head is used as a direct slot instead of
* pointing to a node, in which case *@nodep will be NULL.
*/
void *__radix_tree_lookup(const struct radix_tree_root *root,
restart:
parent = NULL;
- slot = (void __rcu **)&root->rnode;
+ slot = (void __rcu **)&root->xa_head;
radix_tree_load_root(root, &node, &maxindex);
if (index > maxindex)
return NULL;
parent = entry_to_node(node);
offset = radix_tree_descend(parent, &node, index);
slot = parent->slots + offset;
+ if (parent->shift == 0)
+ break;
}
if (nodep)
}
EXPORT_SYMBOL(radix_tree_lookup);
-static inline void replace_sibling_entries(struct radix_tree_node *node,
- void __rcu **slot, int count, int exceptional)
-{
-#ifdef CONFIG_RADIX_TREE_MULTIORDER
- void *ptr = node_to_entry(slot);
- unsigned offset = get_slot_offset(node, slot) + 1;
-
- while (offset < RADIX_TREE_MAP_SIZE) {
- if (rcu_dereference_raw(node->slots[offset]) != ptr)
- break;
- if (count < 0) {
- node->slots[offset] = NULL;
- node->count--;
- }
- node->exceptional += exceptional;
- offset++;
- }
-#endif
-}
-
static void replace_slot(void __rcu **slot, void *item,
- struct radix_tree_node *node, int count, int exceptional)
+ struct radix_tree_node *node, int count, int values)
{
- if (WARN_ON_ONCE(radix_tree_is_internal_node(item)))
- return;
-
- if (node && (count || exceptional)) {
+ if (node && (count || values)) {
node->count += count;
- node->exceptional += exceptional;
- replace_sibling_entries(node, slot, count, exceptional);
+ node->nr_values += values;
}
rcu_assign_pointer(*slot, item);
* @node: pointer to tree node
* @slot: pointer to slot in @node
* @item: new item to store in the slot.
- * @update_node: callback for changing leaf nodes
*
* For use with __radix_tree_lookup(). Caller must hold tree write locked
* across slot lookup and replacement.
*/
void __radix_tree_replace(struct radix_tree_root *root,
struct radix_tree_node *node,
- void __rcu **slot, void *item,
- radix_tree_update_node_t update_node)
+ void __rcu **slot, void *item)
{
void *old = rcu_dereference_raw(*slot);
- int exceptional = !!radix_tree_exceptional_entry(item) -
- !!radix_tree_exceptional_entry(old);
+ int values = !!xa_is_value(item) - !!xa_is_value(old);
int count = calculate_count(root, node, slot, item, old);
/*
- * This function supports replacing exceptional entries and
+ * This function supports replacing value entries and
* deleting entries, but that needs accounting against the
- * node unless the slot is root->rnode.
+ * node unless the slot is root->xa_head.
*/
- WARN_ON_ONCE(!node && (slot != (void __rcu **)&root->rnode) &&
- (count || exceptional));
- replace_slot(slot, item, node, count, exceptional);
+ WARN_ON_ONCE(!node && (slot != (void __rcu **)&root->xa_head) &&
+ (count || values));
+ replace_slot(slot, item, node, count, values);
if (!node)
return;
- if (update_node)
- update_node(node);
-
- delete_node(root, node, update_node);
+ delete_node(root, node);
}
/**
* @slot: pointer to slot
* @item: new item to store in the slot.
*
- * For use with radix_tree_lookup_slot(), radix_tree_gang_lookup_slot(),
+ * For use with radix_tree_lookup_slot() and
* radix_tree_gang_lookup_tag_slot(). Caller must hold tree write locked
* across slot lookup and replacement.
*
* NOTE: This cannot be used to switch between non-entries (empty slots),
- * regular entries, and exceptional entries, as that requires accounting
+ * regular entries, and value entries, as that requires accounting
* inside the radix tree node. When switching from one type of entry or
* deleting, use __radix_tree_lookup() and __radix_tree_replace() or
* radix_tree_iter_replace().
void radix_tree_replace_slot(struct radix_tree_root *root,
void __rcu **slot, void *item)
{
- __radix_tree_replace(root, NULL, slot, item, NULL);
+ __radix_tree_replace(root, NULL, slot, item);
}
EXPORT_SYMBOL(radix_tree_replace_slot);
* @slot: pointer to slot
* @item: new item to store in the slot.
*
- * For use with radix_tree_split() and radix_tree_for_each_slot().
- * Caller must hold tree write locked across split and replacement.
+ * For use with radix_tree_for_each_slot().
+ * Caller must hold tree write locked.
*/
void radix_tree_iter_replace(struct radix_tree_root *root,
const struct radix_tree_iter *iter,
void __rcu **slot, void *item)
{
- __radix_tree_replace(root, iter->node, slot, item, NULL);
+ __radix_tree_replace(root, iter->node, slot, item);
}
-#ifdef CONFIG_RADIX_TREE_MULTIORDER
-/**
- * radix_tree_join - replace multiple entries with one multiorder entry
- * @root: radix tree root
- * @index: an index inside the new entry
- * @order: order of the new entry
- * @item: new entry
- *
- * Call this function to replace several entries with one larger entry.
- * The existing entries are presumed to not need freeing as a result of
- * this call.
- *
- * The replacement entry will have all the tags set on it that were set
- * on any of the entries it is replacing.
- */
-int radix_tree_join(struct radix_tree_root *root, unsigned long index,
- unsigned order, void *item)
-{
- struct radix_tree_node *node;
- void __rcu **slot;
- int error;
-
- BUG_ON(radix_tree_is_internal_node(item));
-
- error = __radix_tree_create(root, index, order, &node, &slot);
- if (!error)
- error = insert_entries(node, slot, item, order, true);
- if (error > 0)
- error = 0;
-
- return error;
-}
-
-/**
- * radix_tree_split - Split an entry into smaller entries
- * @root: radix tree root
- * @index: An index within the large entry
- * @order: Order of new entries
- *
- * Call this function as the first step in replacing a multiorder entry
- * with several entries of lower order. After this function returns,
- * loop over the relevant portion of the tree using radix_tree_for_each_slot()
- * and call radix_tree_iter_replace() to set up each new entry.
- *
- * The tags from this entry are replicated to all the new entries.
- *
- * The radix tree should be locked against modification during the entire
- * replacement operation. Lock-free lookups will see RADIX_TREE_RETRY which
- * should prompt RCU walkers to restart the lookup from the root.
- */
-int radix_tree_split(struct radix_tree_root *root, unsigned long index,
- unsigned order)
-{
- struct radix_tree_node *parent, *node, *child;
- void __rcu **slot;
- unsigned int offset, end;
- unsigned n, tag, tags = 0;
- gfp_t gfp = root_gfp_mask(root);
-
- if (!__radix_tree_lookup(root, index, &parent, &slot))
- return -ENOENT;
- if (!parent)
- return -ENOENT;
-
- offset = get_slot_offset(parent, slot);
-
- for (tag = 0; tag < RADIX_TREE_MAX_TAGS; tag++)
- if (tag_get(parent, tag, offset))
- tags |= 1 << tag;
-
- for (end = offset + 1; end < RADIX_TREE_MAP_SIZE; end++) {
- if (!is_sibling_entry(parent,
- rcu_dereference_raw(parent->slots[end])))
- break;
- for (tag = 0; tag < RADIX_TREE_MAX_TAGS; tag++)
- if (tags & (1 << tag))
- tag_set(parent, tag, end);
- /* rcu_assign_pointer ensures tags are set before RETRY */
- rcu_assign_pointer(parent->slots[end], RADIX_TREE_RETRY);
- }
- rcu_assign_pointer(parent->slots[offset], RADIX_TREE_RETRY);
- parent->exceptional -= (end - offset);
-
- if (order == parent->shift)
- return 0;
- if (order > parent->shift) {
- while (offset < end)
- offset += insert_entries(parent, &parent->slots[offset],
- RADIX_TREE_RETRY, order, true);
- return 0;
- }
-
- node = parent;
-
- for (;;) {
- if (node->shift > order) {
- child = radix_tree_node_alloc(gfp, node, root,
- node->shift - RADIX_TREE_MAP_SHIFT,
- offset, 0, 0);
- if (!child)
- goto nomem;
- if (node != parent) {
- node->count++;
- rcu_assign_pointer(node->slots[offset],
- node_to_entry(child));
- for (tag = 0; tag < RADIX_TREE_MAX_TAGS; tag++)
- if (tags & (1 << tag))
- tag_set(node, tag, offset);
- }
-
- node = child;
- offset = 0;
- continue;
- }
-
- n = insert_entries(node, &node->slots[offset],
- RADIX_TREE_RETRY, order, false);
- BUG_ON(n > RADIX_TREE_MAP_SIZE);
-
- for (tag = 0; tag < RADIX_TREE_MAX_TAGS; tag++)
- if (tags & (1 << tag))
- tag_set(node, tag, offset);
- offset += n;
-
- while (offset == RADIX_TREE_MAP_SIZE) {
- if (node == parent)
- break;
- offset = node->offset;
- child = node;
- node = node->parent;
- rcu_assign_pointer(node->slots[offset],
- node_to_entry(child));
- offset++;
- }
- if ((node == parent) && (offset == end))
- return 0;
- }
-
- nomem:
- /* Shouldn't happen; did user forget to preload? */
- /* TODO: free all the allocated nodes */
- WARN_ON(1);
- return -ENOMEM;
-}
-#endif
-
static void node_tag_set(struct radix_tree_root *root,
struct radix_tree_node *node,
unsigned int tag, unsigned int offset)
}
EXPORT_SYMBOL(radix_tree_tag_set);
-/**
- * radix_tree_iter_tag_set - set a tag on the current iterator entry
- * @root: radix tree root
- * @iter: iterator state
- * @tag: tag to set
- */
-void radix_tree_iter_tag_set(struct radix_tree_root *root,
- const struct radix_tree_iter *iter, unsigned int tag)
-{
- node_tag_set(root, iter->node, tag, iter_offset(iter));
-}
-
static void node_tag_clear(struct radix_tree_root *root,
struct radix_tree_node *node,
unsigned int tag, unsigned int offset)
}
EXPORT_SYMBOL(radix_tree_tag_get);
-static inline void __set_iter_shift(struct radix_tree_iter *iter,
- unsigned int shift)
-{
-#ifdef CONFIG_RADIX_TREE_MULTIORDER
- iter->shift = shift;
-#endif
-}
-
/* Construct iter->tags bit-mask from node->tags[tag] array */
static void set_iter_tags(struct radix_tree_iter *iter,
struct radix_tree_node *node, unsigned offset,
}
}
-#ifdef CONFIG_RADIX_TREE_MULTIORDER
-static void __rcu **skip_siblings(struct radix_tree_node **nodep,
- void __rcu **slot, struct radix_tree_iter *iter)
-{
- while (iter->index < iter->next_index) {
- *nodep = rcu_dereference_raw(*slot);
- if (*nodep && !is_sibling_entry(iter->node, *nodep))
- return slot;
- slot++;
- iter->index = __radix_tree_iter_add(iter, 1);
- iter->tags >>= 1;
- }
-
- *nodep = NULL;
- return NULL;
-}
-
-void __rcu **__radix_tree_next_slot(void __rcu **slot,
- struct radix_tree_iter *iter, unsigned flags)
-{
- unsigned tag = flags & RADIX_TREE_ITER_TAG_MASK;
- struct radix_tree_node *node;
-
- slot = skip_siblings(&node, slot, iter);
-
- while (radix_tree_is_internal_node(node)) {
- unsigned offset;
- unsigned long next_index;
-
- if (node == RADIX_TREE_RETRY)
- return slot;
- node = entry_to_node(node);
- iter->node = node;
- iter->shift = node->shift;
-
- if (flags & RADIX_TREE_ITER_TAGGED) {
- offset = radix_tree_find_next_bit(node, tag, 0);
- if (offset == RADIX_TREE_MAP_SIZE)
- return NULL;
- slot = &node->slots[offset];
- iter->index = __radix_tree_iter_add(iter, offset);
- set_iter_tags(iter, node, offset, tag);
- node = rcu_dereference_raw(*slot);
- } else {
- offset = 0;
- slot = &node->slots[0];
- for (;;) {
- node = rcu_dereference_raw(*slot);
- if (node)
- break;
- slot++;
- offset++;
- if (offset == RADIX_TREE_MAP_SIZE)
- return NULL;
- }
- iter->index = __radix_tree_iter_add(iter, offset);
- }
- if ((flags & RADIX_TREE_ITER_CONTIG) && (offset > 0))
- goto none;
- next_index = (iter->index | shift_maxindex(iter->shift)) + 1;
- if (next_index < iter->next_index)
- iter->next_index = next_index;
- }
-
- return slot;
- none:
- iter->next_index = 0;
- return NULL;
-}
-EXPORT_SYMBOL(__radix_tree_next_slot);
-#else
-static void __rcu **skip_siblings(struct radix_tree_node **nodep,
- void __rcu **slot, struct radix_tree_iter *iter)
-{
- return slot;
-}
-#endif
-
void __rcu **radix_tree_iter_resume(void __rcu **slot,
struct radix_tree_iter *iter)
{
- struct radix_tree_node *node;
-
slot++;
iter->index = __radix_tree_iter_add(iter, 1);
- skip_siblings(&node, slot, iter);
iter->next_index = iter->index;
iter->tags = 0;
return NULL;
iter->next_index = maxindex + 1;
iter->tags = 1;
iter->node = NULL;
- __set_iter_shift(iter, 0);
- return (void __rcu **)&root->rnode;
+ return (void __rcu **)&root->xa_head;
}
do {
while (++offset < RADIX_TREE_MAP_SIZE) {
void *slot = rcu_dereference_raw(
node->slots[offset]);
- if (is_sibling_entry(node, slot))
- continue;
if (slot)
break;
}
goto restart;
if (child == RADIX_TREE_RETRY)
break;
- } while (radix_tree_is_internal_node(child));
+ } while (node->shift && radix_tree_is_internal_node(child));
/* Update the iterator state */
- iter->index = (index &~ node_maxindex(node)) | (offset << node->shift);
+ iter->index = (index &~ node_maxindex(node)) | offset;
iter->next_index = (index | node_maxindex(node)) + 1;
iter->node = node;
- __set_iter_shift(iter, node->shift);
if (flags & RADIX_TREE_ITER_TAGGED)
set_iter_tags(iter, node, offset, tag);
}
EXPORT_SYMBOL(radix_tree_gang_lookup);
-/**
- * radix_tree_gang_lookup_slot - perform multiple slot lookup on radix tree
- * @root: radix tree root
- * @results: where the results of the lookup are placed
- * @indices: where their indices should be placed (but usually NULL)
- * @first_index: start the lookup from this key
- * @max_items: place up to this many items at *results
- *
- * Performs an index-ascending scan of the tree for present items. Places
- * their slots at *@results and returns the number of items which were
- * placed at *@results.
- *
- * The implementation is naive.
- *
- * Like radix_tree_gang_lookup as far as RCU and locking goes. Slots must
- * be dereferenced with radix_tree_deref_slot, and if using only RCU
- * protection, radix_tree_deref_slot may fail requiring a retry.
- */
-unsigned int
-radix_tree_gang_lookup_slot(const struct radix_tree_root *root,
- void __rcu ***results, unsigned long *indices,
- unsigned long first_index, unsigned int max_items)
-{
- struct radix_tree_iter iter;
- void __rcu **slot;
- unsigned int ret = 0;
-
- if (unlikely(!max_items))
- return 0;
-
- radix_tree_for_each_slot(slot, root, &iter, first_index) {
- results[ret] = slot;
- if (indices)
- indices[ret] = iter.index;
- if (++ret == max_items)
- break;
- }
-
- return ret;
-}
-EXPORT_SYMBOL(radix_tree_gang_lookup_slot);
-
/**
* radix_tree_gang_lookup_tag - perform multiple lookup on a radix tree
* based on a tag
}
EXPORT_SYMBOL(radix_tree_gang_lookup_tag_slot);
-/**
- * __radix_tree_delete_node - try to free node after clearing a slot
- * @root: radix tree root
- * @node: node containing @index
- * @update_node: callback for changing leaf nodes
- *
- * After clearing the slot at @index in @node from radix tree
- * rooted at @root, call this function to attempt freeing the
- * node and shrinking the tree.
- */
-void __radix_tree_delete_node(struct radix_tree_root *root,
- struct radix_tree_node *node,
- radix_tree_update_node_t update_node)
-{
- delete_node(root, node, update_node);
-}
-
static bool __radix_tree_delete(struct radix_tree_root *root,
struct radix_tree_node *node, void __rcu **slot)
{
void *old = rcu_dereference_raw(*slot);
- int exceptional = radix_tree_exceptional_entry(old) ? -1 : 0;
+ int values = xa_is_value(old) ? -1 : 0;
unsigned offset = get_slot_offset(node, slot);
int tag;
for (tag = 0; tag < RADIX_TREE_MAX_TAGS; tag++)
node_tag_clear(root, node, tag, offset);
- replace_slot(slot, NULL, node, -1, exceptional);
- return node && delete_node(root, node, NULL);
+ replace_slot(slot, NULL, node, -1, values);
+ return node && delete_node(root, node);
}
/**
}
EXPORT_SYMBOL(radix_tree_delete);
-void radix_tree_clear_tags(struct radix_tree_root *root,
- struct radix_tree_node *node,
- void __rcu **slot)
-{
- if (node) {
- unsigned int tag, offset = get_slot_offset(node, slot);
- for (tag = 0; tag < RADIX_TREE_MAX_TAGS; tag++)
- node_tag_clear(root, node, tag, offset);
- } else {
- root_tag_clear_all(root);
- }
-}
-
/**
* radix_tree_tagged - test whether any items in the tree are tagged
* @root: radix tree root
}
EXPORT_SYMBOL(idr_preload);
-int ida_pre_get(struct ida *ida, gfp_t gfp)
-{
- /*
- * The IDA API has no preload_end() equivalent. Instead,
- * ida_get_new() can return -EAGAIN, prompting the caller
- * to return to the ida_pre_get() step.
- */
- if (!__radix_tree_preload(gfp, IDA_PRELOAD_SIZE))
- preempt_enable();
-
- if (!this_cpu_read(ida_bitmap)) {
- struct ida_bitmap *bitmap = kzalloc(sizeof(*bitmap), gfp);
- if (!bitmap)
- return 0;
- if (this_cpu_cmpxchg(ida_bitmap, NULL, bitmap))
- kfree(bitmap);
- }
-
- return 1;
-}
-
void __rcu **idr_get_free(struct radix_tree_root *root,
struct radix_tree_iter *iter, gfp_t gfp,
unsigned long max)
{
struct radix_tree_node *node = NULL, *child;
- void __rcu **slot = (void __rcu **)&root->rnode;
+ void __rcu **slot = (void __rcu **)&root->xa_head;
unsigned long maxindex, start = iter->next_index;
unsigned int shift, offset = 0;
if (error < 0)
return ERR_PTR(error);
shift = error;
- child = rcu_dereference_raw(root->rnode);
+ child = rcu_dereference_raw(root->xa_head);
}
+ if (start == 0 && shift == 0)
+ shift = RADIX_TREE_MAP_SHIFT;
while (shift) {
shift -= RADIX_TREE_MAP_SHIFT;
else
iter->next_index = 1;
iter->node = node;
- __set_iter_shift(iter, shift);
set_iter_tags(iter, node, offset, IDR_FREE);
return slot;
*/
void idr_destroy(struct idr *idr)
{
- struct radix_tree_node *node = rcu_dereference_raw(idr->idr_rt.rnode);
+ struct radix_tree_node *node = rcu_dereference_raw(idr->idr_rt.xa_head);
if (radix_tree_is_internal_node(node))
radix_tree_free_nodes(node);
- idr->idr_rt.rnode = NULL;
+ idr->idr_rt.xa_head = NULL;
root_tag_set(&idr->idr_rt, IDR_FREE);
}
EXPORT_SYMBOL(idr_destroy);
INIT_LIST_HEAD(&node->private_list);
}
-static __init unsigned long __maxindex(unsigned int height)
-{
- unsigned int width = height * RADIX_TREE_MAP_SHIFT;
- int shift = RADIX_TREE_INDEX_BITS - width;
-
- if (shift < 0)
- return ~0UL;
- if (shift >= BITS_PER_LONG)
- return 0UL;
- return ~0UL >> shift;
-}
-
-static __init void radix_tree_init_maxnodes(void)
-{
- unsigned long height_to_maxindex[RADIX_TREE_MAX_PATH + 1];
- unsigned int i, j;
-
- for (i = 0; i < ARRAY_SIZE(height_to_maxindex); i++)
- height_to_maxindex[i] = __maxindex(i);
- for (i = 0; i < ARRAY_SIZE(height_to_maxnodes); i++) {
- for (j = i; j > 0; j--)
- height_to_maxnodes[i] += height_to_maxindex[j - 1] + 1;
- }
-}
-
static int radix_tree_cpu_dead(unsigned int cpu)
{
struct radix_tree_preload *rtp;
kmem_cache_free(radix_tree_node_cachep, node);
rtp->nr--;
}
- kfree(per_cpu(ida_bitmap, cpu));
- per_cpu(ida_bitmap, cpu) = NULL;
return 0;
}
BUILD_BUG_ON(RADIX_TREE_MAX_TAGS + __GFP_BITS_SHIFT > 32);
BUILD_BUG_ON(ROOT_IS_IDR & ~GFP_ZONEMASK);
+ BUILD_BUG_ON(XA_CHUNK_SIZE > 255);
radix_tree_node_cachep = kmem_cache_create("radix_tree_node",
sizeof(struct radix_tree_node), 0,
SLAB_PANIC | SLAB_RECLAIM_ACCOUNT,
radix_tree_node_ctor);
- radix_tree_init_maxnodes();
ret = cpuhp_setup_state_nocalls(CPUHP_RADIX_DEAD, "lib/radix:dead",
NULL, radix_tree_cpu_dead);
WARN_ON(ret < 0);
git.samba.org / sfrench / cifs-2.6.git / blobdiff