btrfs: Fix grossly misleading argument names in extent io search

The variables and function parameters of __etree_search which pertain to
prev/next are grossly misnamed. Namely, prev_ret holds the next state
and not the previous. Similarly, next_ret actually holds the previous
extent state relating to the offset we are interested in. Fix this by
renaming the variables as well as switching the arguments order. No
functional changes.

Signed-off-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 67fec85c94d9641b6d6bfdc04e3b2ca57b5c792d..90ecce8572631472fc3846d7d61b4b474ee007cd 100644 (file)
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -281,8 +281,8 @@ do_insert:
 }
 
 static struct rb_node *__etree_search(struct extent_io_tree *tree, u64 offset,
-                                     struct rb_node **prev_ret,
                                      struct rb_node **next_ret,
+                                     struct rb_node **prev_ret,
                                      struct rb_node ***p_ret,
                                      struct rb_node **parent_ret)
 {
@@ -311,23 +311,23 @@ static struct rb_node *__etree_search(struct extent_io_tree *tree, u64 offset,
        if (parent_ret)
                *parent_ret = prev;
 
-       if (prev_ret) {
+       if (next_ret) {
                orig_prev = prev;
                while (prev && offset > prev_entry->end) {
                        prev = rb_next(prev);
                        prev_entry = rb_entry(prev, struct tree_entry, rb_node);
                }
-               *prev_ret = prev;
+               *next_ret = prev;
                prev = orig_prev;
        }
 
-       if (next_ret) {
+       if (prev_ret) {
                prev_entry = rb_entry(prev, struct tree_entry, rb_node);
                while (prev && offset < prev_entry->start) {
                        prev = rb_prev(prev);
                        prev_entry = rb_entry(prev, struct tree_entry, rb_node);
                }
-               *next_ret = prev;
+               *prev_ret = prev;
        }
        return NULL;
 }
@@ -338,12 +338,12 @@ tree_search_for_insert(struct extent_io_tree *tree,
                       struct rb_node ***p_ret,
                       struct rb_node **parent_ret)
 {
-       struct rb_node *prev = NULL;
+       struct rb_node *next= NULL;
        struct rb_node *ret;
 
-       ret = __etree_search(tree, offset, &prev, NULL, p_ret, parent_ret);
+       ret = __etree_search(tree, offset, &next, NULL, p_ret, parent_ret);
        if (!ret)
-               return prev;
+               return next;
        return ret;
 }