--- /dev/null
+/*
+ * Copyright (c) 2014, Cisco Systems, Inc. All rights reserved.
+ *
+ * This program is free software; you may redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; version 2 of the License.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *
+ */
+
+#include <linux/init.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+#include <linux/list_sort.h>
+
+#include <linux/interval_tree_generic.h>
+#include "usnic_uiom_interval_tree.h"
+
+#define START(node) ((node)->start)
+#define LAST(node) ((node)->last)
+
+#define MAKE_NODE(node, start, end, ref_cnt, flags, err, err_out) \
+ do { \
+ node = usnic_uiom_interval_node_alloc(start, \
+ end, ref_cnt, flags); \
+ if (!node) { \
+ err = -ENOMEM; \
+ goto err_out; \
+ } \
+ } while (0)
+
+#define MARK_FOR_ADD(node, list) (list_add_tail(&node->link, list))
+
+#define MAKE_NODE_AND_APPEND(node, start, end, ref_cnt, flags, err, \
+ err_out, list) \
+ do { \
+ MAKE_NODE(node, start, end, \
+ ref_cnt, flags, err, \
+ err_out); \
+ MARK_FOR_ADD(node, list); \
+ } while (0)
+
+#define FLAGS_EQUAL(flags1, flags2, mask) \
+ (((flags1) & (mask)) == ((flags2) & (mask)))
+
+static struct usnic_uiom_interval_node*
+usnic_uiom_interval_node_alloc(long int start, long int last, int ref_cnt,
+ int flags)
+{
+ struct usnic_uiom_interval_node *interval = kzalloc(sizeof(*interval),
+ GFP_ATOMIC);
+ if (!interval)
+ return NULL;
+
+ interval->start = start;
+ interval->last = last;
+ interval->flags = flags;
+ interval->ref_cnt = ref_cnt;
+
+ return interval;
+}
+
+static int interval_cmp(void *priv, struct list_head *a, struct list_head *b)
+{
+ struct usnic_uiom_interval_node *node_a, *node_b;
+
+ node_a = list_entry(a, struct usnic_uiom_interval_node, link);
+ node_b = list_entry(b, struct usnic_uiom_interval_node, link);
+
+ /* long to int */
+ if (node_a->start < node_b->start)
+ return -1;
+ else if (node_a->start > node_b->start)
+ return 1;
+
+ return 0;
+}
+
+static void
+find_intervals_intersection_sorted(struct rb_root *root, unsigned long start,
+ unsigned long last,
+ struct list_head *list)
+{
+ struct usnic_uiom_interval_node *node;
+
+ INIT_LIST_HEAD(list);
+
+ for (node = usnic_uiom_interval_tree_iter_first(root, start, last);
+ node;
+ node = usnic_uiom_interval_tree_iter_next(node, start, last))
+ list_add_tail(&node->link, list);
+
+ list_sort(NULL, list, interval_cmp);
+}
+
+int usnic_uiom_get_intervals_diff(unsigned long start, unsigned long last,
+ int flags, int flag_mask,
+ struct rb_root *root,
+ struct list_head *diff_set)
+{
+ struct usnic_uiom_interval_node *interval, *tmp;
+ int err = 0;
+ long int pivot = start;
+ LIST_HEAD(intersection_set);
+
+ INIT_LIST_HEAD(diff_set);
+
+ find_intervals_intersection_sorted(root, start, last,
+ &intersection_set);
+
+ list_for_each_entry(interval, &intersection_set, link) {
+ if (pivot < interval->start) {
+ MAKE_NODE_AND_APPEND(tmp, pivot, interval->start - 1,
+ 1, flags, err, err_out,
+ diff_set);
+ pivot = interval->start;
+ }
+
+ /*
+ * Invariant: Set [start, pivot] is either in diff_set or root,
+ * but not in both.
+ */
+
+ if (pivot > interval->last) {
+ continue;
+ } else if (pivot <= interval->last &&
+ FLAGS_EQUAL(interval->flags, flags,
+ flag_mask)) {
+ pivot = interval->last + 1;
+ }
+ }
+
+ if (pivot <= last)
+ MAKE_NODE_AND_APPEND(tmp, pivot, last, 1, flags, err, err_out,
+ diff_set);
+
+ return 0;
+
+err_out:
+ list_for_each_entry_safe(interval, tmp, diff_set, link) {
+ list_del(&interval->link);
+ kfree(interval);
+ }
+
+ return err;
+}
+
+void usnic_uiom_put_interval_set(struct list_head *intervals)
+{
+ struct usnic_uiom_interval_node *interval, *tmp;
+ list_for_each_entry_safe(interval, tmp, intervals, link)
+ kfree(interval);
+}
+
+int usnic_uiom_insert_interval(struct rb_root *root, unsigned long start,
+ unsigned long last, int flags)
+{
+ struct usnic_uiom_interval_node *interval, *tmp;
+ unsigned long istart, ilast;
+ int iref_cnt, iflags;
+ unsigned long lpivot = start;
+ int err = 0;
+ LIST_HEAD(to_add);
+ LIST_HEAD(intersection_set);
+
+ find_intervals_intersection_sorted(root, start, last,
+ &intersection_set);
+
+ list_for_each_entry(interval, &intersection_set, link) {
+ /*
+ * Invariant - lpivot is the left edge of next interval to be
+ * inserted
+ */
+ istart = interval->start;
+ ilast = interval->last;
+ iref_cnt = interval->ref_cnt;
+ iflags = interval->flags;
+
+ if (istart < lpivot) {
+ MAKE_NODE_AND_APPEND(tmp, istart, lpivot - 1, iref_cnt,
+ iflags, err, err_out, &to_add);
+ } else if (istart > lpivot) {
+ MAKE_NODE_AND_APPEND(tmp, lpivot, istart - 1, 1, flags,
+ err, err_out, &to_add);
+ lpivot = istart;
+ } else {
+ lpivot = istart;
+ }
+
+ if (ilast > last) {
+ MAKE_NODE_AND_APPEND(tmp, lpivot, last, iref_cnt + 1,
+ iflags | flags, err, err_out,
+ &to_add);
+ MAKE_NODE_AND_APPEND(tmp, last + 1, ilast, iref_cnt,
+ iflags, err, err_out, &to_add);
+ } else {
+ MAKE_NODE_AND_APPEND(tmp, lpivot, ilast, iref_cnt + 1,
+ iflags | flags, err, err_out,
+ &to_add);
+ }
+
+ lpivot = ilast + 1;
+ }
+
+ if (lpivot <= last)
+ MAKE_NODE_AND_APPEND(tmp, lpivot, last, 1, flags, err, err_out,
+ &to_add);
+
+ list_for_each_entry_safe(interval, tmp, &intersection_set, link) {
+ usnic_uiom_interval_tree_remove(interval, root);
+ kfree(interval);
+ }
+
+ list_for_each_entry(interval, &to_add, link)
+ usnic_uiom_interval_tree_insert(interval, root);
+
+ return 0;
+
+err_out:
+ list_for_each_entry_safe(interval, tmp, &to_add, link)
+ kfree(interval);
+
+ return err;
+}
+
+void usnic_uiom_remove_interval(struct rb_root *root, unsigned long start,
+ unsigned long last, struct list_head *removed)
+{
+ struct usnic_uiom_interval_node *interval;
+
+ for (interval = usnic_uiom_interval_tree_iter_first(root, start, last);
+ interval;
+ interval = usnic_uiom_interval_tree_iter_next(interval,
+ start,
+ last)) {
+ if (--interval->ref_cnt == 0)
+ list_add_tail(&interval->link, removed);
+ }
+
+ list_for_each_entry(interval, removed, link)
+ usnic_uiom_interval_tree_remove(interval, root);
+}
+
+INTERVAL_TREE_DEFINE(struct usnic_uiom_interval_node, rb,
+ unsigned long, __subtree_last,
+ START, LAST, , usnic_uiom_interval_tree)
Code Review / kvmfornfv.git / blobdiff