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-rw-r--r--arch/x86/mm/pat_rbtree.c162
1 files changed, 42 insertions, 120 deletions
diff --git a/arch/x86/mm/pat_rbtree.c b/arch/x86/mm/pat_rbtree.c
index 65ebe4b88f7c..c3d119cd155d 100644
--- a/arch/x86/mm/pat_rbtree.c
+++ b/arch/x86/mm/pat_rbtree.c
@@ -5,14 +5,13 @@
* Authors: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
* Suresh B Siddha <suresh.b.siddha@intel.com>
*
- * Interval tree (augmented rbtree) used to store the PAT memory type
- * reservations.
+ * Interval tree used to store the PAT memory type reservations.
*/
#include <linux/seq_file.h>
#include <linux/debugfs.h>
#include <linux/kernel.h>
-#include <linux/rbtree_augmented.h>
+#include <linux/interval_tree_generic.h>
#include <linux/sched.h>
#include <linux/gfp.h>
@@ -33,72 +32,33 @@
*
* memtype_lock protects the rbtree.
*/
-
-static struct rb_root memtype_rbroot = RB_ROOT;
-
-static int is_node_overlap(struct memtype *node, u64 start, u64 end)
+static inline u64 memtype_interval_start(struct memtype *memtype)
{
- if (node->start >= end || node->end <= start)
- return 0;
-
- return 1;
+ return memtype->start;
}
-static u64 get_subtree_max_end(struct rb_node *node)
+static inline u64 memtype_interval_end(struct memtype *memtype)
{
- u64 ret = 0;
- if (node) {
- struct memtype *data = rb_entry(node, struct memtype, rb);
- ret = data->subtree_max_end;
- }
- return ret;
+ return memtype->end - 1;
}
+INTERVAL_TREE_DEFINE(struct memtype, rb, u64, subtree_max_end,
+ memtype_interval_start, memtype_interval_end,
+ static, memtype_interval)
-#define NODE_END(node) ((node)->end)
-
-RB_DECLARE_CALLBACKS_MAX(static, memtype_rb_augment_cb,
- struct memtype, rb, u64, subtree_max_end, NODE_END)
-
-/* Find the first (lowest start addr) overlapping range from rb tree */
-static struct memtype *memtype_rb_lowest_match(struct rb_root *root,
- u64 start, u64 end)
-{
- struct rb_node *node = root->rb_node;
- struct memtype *last_lower = NULL;
-
- while (node) {
- struct memtype *data = rb_entry(node, struct memtype, rb);
-
- if (get_subtree_max_end(node->rb_left) > start) {
- /* Lowest overlap if any must be on left side */
- node = node->rb_left;
- } else if (is_node_overlap(data, start, end)) {
- last_lower = data;
- break;
- } else if (start >= data->start) {
- /* Lowest overlap if any must be on right side */
- node = node->rb_right;
- } else {
- break;
- }
- }
- return last_lower; /* Returns NULL if there is no overlap */
-}
+static struct rb_root_cached memtype_rbroot = RB_ROOT_CACHED;
enum {
MEMTYPE_EXACT_MATCH = 0,
MEMTYPE_END_MATCH = 1
};
-static struct memtype *memtype_rb_match(struct rb_root *root,
- u64 start, u64 end, int match_type)
+static struct memtype *memtype_match(struct rb_root_cached *root,
+ u64 start, u64 end, int match_type)
{
struct memtype *match;
- match = memtype_rb_lowest_match(root, start, end);
+ match = memtype_interval_iter_first(root, start, end);
while (match != NULL && match->start < end) {
- struct rb_node *node;
-
if ((match_type == MEMTYPE_EXACT_MATCH) &&
(match->start == start) && (match->end == end))
return match;
@@ -107,26 +67,21 @@ static struct memtype *memtype_rb_match(struct rb_root *root,
(match->start < start) && (match->end == end))
return match;
- node = rb_next(&match->rb);
- if (node)
- match = rb_entry(node, struct memtype, rb);
- else
- match = NULL;
+ match = memtype_interval_iter_next(match, start, end);
}
return NULL; /* Returns NULL if there is no match */
}
-static int memtype_rb_check_conflict(struct rb_root *root,
+static int memtype_rb_check_conflict(struct rb_root_cached *root,
u64 start, u64 end,
enum page_cache_mode reqtype,
enum page_cache_mode *newtype)
{
- struct rb_node *node;
struct memtype *match;
enum page_cache_mode found_type = reqtype;
- match = memtype_rb_lowest_match(&memtype_rbroot, start, end);
+ match = memtype_interval_iter_first(&memtype_rbroot, start, end);
if (match == NULL)
goto success;
@@ -136,19 +91,12 @@ static int memtype_rb_check_conflict(struct rb_root *root,
dprintk("Overlap at 0x%Lx-0x%Lx\n", match->start, match->end);
found_type = match->type;
- node = rb_next(&match->rb);
- while (node) {
- match = rb_entry(node, struct memtype, rb);
-
- if (match->start >= end) /* Checked all possible matches */
- goto success;
-
- if (is_node_overlap(match, start, end) &&
- match->type != found_type) {
+ match = memtype_interval_iter_next(match, start, end);
+ while (match) {
+ if (match->type != found_type)
goto failure;
- }
- node = rb_next(&match->rb);
+ match = memtype_interval_iter_next(match, start, end);
}
success:
if (newtype)
@@ -163,44 +111,21 @@ failure:
return -EBUSY;
}
-static void memtype_rb_insert(struct rb_root *root, struct memtype *newdata)
-{
- struct rb_node **node = &(root->rb_node);
- struct rb_node *parent = NULL;
-
- while (*node) {
- struct memtype *data = rb_entry(*node, struct memtype, rb);
-
- parent = *node;
- if (data->subtree_max_end < newdata->end)
- data->subtree_max_end = newdata->end;
- if (newdata->start <= data->start)
- node = &((*node)->rb_left);
- else if (newdata->start > data->start)
- node = &((*node)->rb_right);
- }
-
- newdata->subtree_max_end = newdata->end;
- rb_link_node(&newdata->rb, parent, node);
- rb_insert_augmented(&newdata->rb, root, &memtype_rb_augment_cb);
-}
-
int rbt_memtype_check_insert(struct memtype *new,
enum page_cache_mode *ret_type)
{
int err = 0;
err = memtype_rb_check_conflict(&memtype_rbroot, new->start, new->end,
- new->type, ret_type);
+ new->type, ret_type);
+ if (err)
+ return err;
- if (!err) {
- if (ret_type)
- new->type = *ret_type;
+ if (ret_type)
+ new->type = *ret_type;
- new->subtree_max_end = new->end;
- memtype_rb_insert(&memtype_rbroot, new);
- }
- return err;
+ memtype_interval_insert(new, &memtype_rbroot);
+ return 0;
}
struct memtype *rbt_memtype_erase(u64 start, u64 end)
@@ -214,26 +139,23 @@ struct memtype *rbt_memtype_erase(u64 start, u64 end)
* it then checks with END_MATCH, i.e. shrink the size of a node
* from the end for the mremap case.
*/
- data = memtype_rb_match(&memtype_rbroot, start, end,
- MEMTYPE_EXACT_MATCH);
+ data = memtype_match(&memtype_rbroot, start, end,
+ MEMTYPE_EXACT_MATCH);
if (!data) {
- data = memtype_rb_match(&memtype_rbroot, start, end,
- MEMTYPE_END_MATCH);
+ data = memtype_match(&memtype_rbroot, start, end,
+ MEMTYPE_END_MATCH);
if (!data)
return ERR_PTR(-EINVAL);
}
if (data->start == start) {
/* munmap: erase this node */
- rb_erase_augmented(&data->rb, &memtype_rbroot,
- &memtype_rb_augment_cb);
+ memtype_interval_remove(data, &memtype_rbroot);
} else {
/* mremap: update the end value of this node */
- rb_erase_augmented(&data->rb, &memtype_rbroot,
- &memtype_rb_augment_cb);
+ memtype_interval_remove(data, &memtype_rbroot);
data->end = start;
- data->subtree_max_end = data->end;
- memtype_rb_insert(&memtype_rbroot, data);
+ memtype_interval_insert(data, &memtype_rbroot);
return NULL;
}
@@ -242,24 +164,24 @@ struct memtype *rbt_memtype_erase(u64 start, u64 end)
struct memtype *rbt_memtype_lookup(u64 addr)
{
- return memtype_rb_lowest_match(&memtype_rbroot, addr, addr + PAGE_SIZE);
+ return memtype_interval_iter_first(&memtype_rbroot, addr,
+ addr + PAGE_SIZE);
}
#if defined(CONFIG_DEBUG_FS)
int rbt_memtype_copy_nth_element(struct memtype *out, loff_t pos)
{
- struct rb_node *node;
+ struct memtype *match;
int i = 1;
- node = rb_first(&memtype_rbroot);
- while (node && pos != i) {
- node = rb_next(node);
+ match = memtype_interval_iter_first(&memtype_rbroot, 0, ULONG_MAX);
+ while (match && pos != i) {
+ match = memtype_interval_iter_next(match, 0, ULONG_MAX);
i++;
}
- if (node) { /* pos == i */
- struct memtype *this = rb_entry(node, struct memtype, rb);
- *out = *this;
+ if (match) { /* pos == i */
+ *out = *match;
return 0;
} else {
return 1;