Btrfs: During deletes and truncate, remove many items at once from the tree

Signed-off-by: Chris Mason <chris.mason@oracle.com>

1 files changed, 20 insertions, 18 deletions

diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index 43d23148a4fe..84ad53e06b3a 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -2514,34 +2514,36 @@ static int del_ptr(struct btrfs_trans_handle *trans, struct btrfs_root *root,
  * delete the item at the leaf level in path.  If that empties
  * the leaf, remove it from the tree
  */
-int btrfs_del_item(struct btrfs_trans_handle *trans, struct btrfs_root *root,
-                   struct btrfs_path *path)
+int btrfs_del_items(struct btrfs_trans_handle *trans, struct btrfs_root *root,
+                    struct btrfs_path *path, int slot, int nr)
 {
-        int slot;
         struct extent_buffer *leaf;
         struct btrfs_item *item;
-        int doff;
-        int dsize;
+        int last_off;
+        int dsize = 0;
         int ret = 0;
         int wret;
+        int i;
         u32 nritems;
 
         leaf = path->nodes[0];
-        slot = path->slots[0];
-        doff = btrfs_item_offset_nr(leaf, slot);
-        dsize = btrfs_item_size_nr(leaf, slot);
+        last_off = btrfs_item_offset_nr(leaf, slot + nr - 1);
+
+        for (i = 0; i < nr; i++)
+                dsize += btrfs_item_size_nr(leaf, slot + i);
+
         nritems = btrfs_header_nritems(leaf);
 
-        if (slot != nritems - 1) {
+        if (slot + nr != nritems) {
                 int i;
                 int data_end = leaf_data_end(root, leaf);
 
                 memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) +
                               data_end + dsize,
                               btrfs_leaf_data(leaf) + data_end,
-                              doff - data_end);
+                              last_off - data_end);
 
-                for (i = slot + 1; i < nritems; i++) {
+                for (i = slot + nr; i < nritems; i++) {
                         u32 ioff;
 
                         item = btrfs_item_nr(leaf, i);
@@ -2562,12 +2564,12 @@ int btrfs_del_item(struct btrfs_trans_handle *trans, struct btrfs_root *root,
                 }
 
                 memmove_extent_buffer(leaf, btrfs_item_nr_offset(slot),
-                              btrfs_item_nr_offset(slot + 1),
+                              btrfs_item_nr_offset(slot + nr),
                               sizeof(struct btrfs_item) *
-                              (nritems - slot - 1));
+                              (nritems - slot - nr));
         }
-        btrfs_set_header_nritems(leaf, nritems - 1);
-        nritems--;
+        btrfs_set_header_nritems(leaf, nritems - nr);
+        nritems -= nr;
 
         /* delete the leaf if we've emptied it */
         if (nritems == 0) {
@@ -2600,7 +2602,7 @@ int btrfs_del_item(struct btrfs_trans_handle *trans, struct btrfs_root *root,
                 }
 
                 /* delete the leaf if it is mostly empty */
-                if (used < BTRFS_LEAF_DATA_SIZE(root) / 3) {
+                if (used < BTRFS_LEAF_DATA_SIZE(root) / 4) {
                         /* push_leaf_left fixes the path.
                          * make sure the path still points to our leaf
                          * for possible call to del_ptr below
@@ -2608,13 +2610,13 @@ int btrfs_del_item(struct btrfs_trans_handle *trans, struct btrfs_root *root,
                         slot = path->slots[1];
                         extent_buffer_get(leaf);
 
-                        wret = push_leaf_right(trans, root, path, 1, 1);
+                        wret = push_leaf_left(trans, root, path, 1, 1);
                         if (wret < 0 && wret != -ENOSPC)
                                 ret = wret;
 
                         if (path->nodes[0] == leaf &&
                             btrfs_header_nritems(leaf)) {
-                                wret = push_leaf_left(trans, root, path, 1, 1);
+                                wret = push_leaf_right(trans, root, path, 1, 1);
                                 if (wret < 0 && wret != -ENOSPC)
                                         ret = wret;
                         }