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

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

4 files changed, 95 insertions, 70 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;
                         }
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 6c65473e0fe3..098cf0883150 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -1038,8 +1038,16 @@ void btrfs_release_path(struct btrfs_root *root, struct btrfs_path *p);
 struct btrfs_path *btrfs_alloc_path(void);
 void btrfs_free_path(struct btrfs_path *p);
 void btrfs_init_path(struct btrfs_path *p);
-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);
+
+static inline int btrfs_del_item(struct btrfs_trans_handle *trans,
+                                 struct btrfs_root *root,
+                                 struct btrfs_path *path)
+{
+        return btrfs_del_items(trans, root, path, path->slots[0], 1);
+}
+
 int btrfs_insert_item(struct btrfs_trans_handle *trans, struct btrfs_root
                       *root, struct btrfs_key *key, void *data, u32 data_size);
 int btrfs_insert_empty_item(struct btrfs_trans_handle *trans, struct btrfs_root
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 1f734c34dc24..8aec72253a17 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -2863,7 +2863,6 @@ int read_extent_buffer_pages(struct extent_io_tree *tree,
         if (ret || !wait) {
                 return ret;
         }
-
         for (i = start_i; i < num_pages; i++) {
                 page = extent_buffer_page(eb, i);
                 wait_on_page_locked(page);
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index bac8722e14e1..0a2fe51c4127 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -692,27 +692,6 @@ fail:
         return err;
 }
 
-static int btrfs_free_inode(struct btrfs_trans_handle *trans,
-                            struct btrfs_root *root,
-                            struct inode *inode)
-{
-        struct btrfs_path *path;
-        int ret;
-
-        clear_inode(inode);
-
-        path = btrfs_alloc_path();
-        BUG_ON(!path);
-        ret = btrfs_lookup_inode(trans, root, path,
-                                 &BTRFS_I(inode)->location, -1);
-        if (ret > 0)
-                ret = -ENOENT;
-        if (!ret)
-                ret = btrfs_del_item(trans, root, path);
-        btrfs_free_path(path);
-        return ret;
-}
-
 /*
  * this can truncate away extent items, csum items and directory items.
  * It starts at a high offset and removes keys until it can't find
@@ -723,7 +702,8 @@ static int btrfs_free_inode(struct btrfs_trans_handle *trans,
  */
 static int btrfs_truncate_in_trans(struct btrfs_trans_handle *trans,
                                    struct btrfs_root *root,
-                                   struct inode *inode)
+                                   struct inode *inode,
+                                   u32 min_type)
 {
         int ret;
         struct btrfs_path *path;
@@ -739,6 +719,8 @@ static int btrfs_truncate_in_trans(struct btrfs_trans_handle *trans,
         u64 root_owner = 0;
         int found_extent;
         int del_item;
+        int pending_del_nr = 0;
+        int pending_del_slot = 0;
         int extent_type = -1;
 
         btrfs_drop_extent_cache(inode, inode->i_size, (u64)-1);
@@ -751,17 +733,19 @@ static int btrfs_truncate_in_trans(struct btrfs_trans_handle *trans,
         key.offset = (u64)-1;
         key.type = (u8)-1;
 
+        btrfs_init_path(path);
+search_again:
+        ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
+        if (ret < 0) {
+                goto error;
+        }
+        if (ret > 0) {
+                BUG_ON(path->slots[0] == 0);
+                path->slots[0]--;
+        }
+
         while(1) {
-                btrfs_init_path(path);
                 fi = NULL;
-                ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
-                if (ret < 0) {
-                        goto error;
-                }
-                if (ret > 0) {
-                        BUG_ON(path->slots[0] == 0);
-                        path->slots[0]--;
-                }
                 leaf = path->nodes[0];
                 btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
                 found_type = btrfs_key_type(&found_key);
@@ -769,10 +753,7 @@ static int btrfs_truncate_in_trans(struct btrfs_trans_handle *trans,
                 if (found_key.objectid != inode->i_ino)
                         break;
 
-                if (found_type != BTRFS_CSUM_ITEM_KEY &&
-                    found_type != BTRFS_DIR_ITEM_KEY &&
-                    found_type != BTRFS_DIR_INDEX_KEY &&
-                    found_type != BTRFS_EXTENT_DATA_KEY)
+                if (found_type < min_type)
                         break;
 
                 item_end = found_key.offset;
@@ -801,14 +782,17 @@ static int btrfs_truncate_in_trans(struct btrfs_trans_handle *trans,
                                 found_type = BTRFS_INODE_ITEM_KEY;
                         } else if (found_type == BTRFS_EXTENT_ITEM_KEY) {
                                 found_type = BTRFS_CSUM_ITEM_KEY;
+                        } else if (found_type == BTRFS_EXTENT_DATA_KEY) {
+                                found_type = BTRFS_XATTR_ITEM_KEY;
+                        } else if (found_type == BTRFS_XATTR_ITEM_KEY) {
+                                found_type = BTRFS_INODE_REF_KEY;
                         } else if (found_type) {
                                 found_type--;
                         } else {
                                 break;
                         }
                         btrfs_set_key_type(&key, found_type);
-                        btrfs_release_path(root, path);
-                        continue;
+                        goto next;
                 }
                 if (found_key.offset >= inode->i_size)
                         del_item = 1;
@@ -860,13 +844,21 @@ static int btrfs_truncate_in_trans(struct btrfs_trans_handle *trans,
                 }
 delete:
                 if (del_item) {
-                        ret = btrfs_del_item(trans, root, path);
-                        if (ret)
-                                goto error;
+                        if (!pending_del_nr) {
+                                /* no pending yet, add ourselves */
+                                pending_del_slot = path->slots[0];
+                                pending_del_nr = 1;
+                        } else if (pending_del_nr &&
+                                   path->slots[0] + 1 == pending_del_slot) {
+                                /* hop on the pending chunk */
+                                pending_del_nr++;
+                                pending_del_slot = path->slots[0];
+                        } else {
+                                printk("bad pending slot %d pending_del_nr %d pending_del_slot %d\n", path->slots[0], pending_del_nr, pending_del_slot);
+                        }
                 } else {
                         break;
                 }
-                btrfs_release_path(root, path);
                 if (found_extent) {
                         ret = btrfs_free_extent(trans, root, extent_start,
                                                 extent_num_bytes,
@@ -875,9 +867,36 @@ delete:
                                                 found_key.offset, 0);
                         BUG_ON(ret);
                 }
+next:
+                if (path->slots[0] == 0) {
+                        if (pending_del_nr)
+                                goto del_pending;
+                        btrfs_release_path(root, path);
+                        goto search_again;
+                }
+
+                path->slots[0]--;
+                if (pending_del_nr &&
+                    path->slots[0] + 1 != pending_del_slot) {
+                        struct btrfs_key debug;
+del_pending:
+                        btrfs_item_key_to_cpu(path->nodes[0], &debug,
+                                              pending_del_slot);
+                        ret = btrfs_del_items(trans, root, path,
+                                              pending_del_slot,
+                                              pending_del_nr);
+                        BUG_ON(ret);
+                        pending_del_nr = 0;
+                        btrfs_release_path(root, path);
+                        goto search_again;
+                }
         }
         ret = 0;
 error:
+        if (pending_del_nr) {
+                ret = btrfs_del_items(trans, root, path, pending_del_slot,
+                                      pending_del_nr);
+        }
         btrfs_release_path(root, path);
         btrfs_free_path(path);
         inode->i_sb->s_dirt = 1;
@@ -1067,16 +1086,12 @@ void btrfs_delete_inode(struct inode *inode)
         trans = btrfs_start_transaction(root, 1);
 
         btrfs_set_trans_block_group(trans, inode);
-        ret = btrfs_truncate_in_trans(trans, root, inode);
-        if (ret)
-                goto no_delete_lock;
-        ret = btrfs_delete_xattrs(trans, root, inode);
-        if (ret)
-                goto no_delete_lock;
-        ret = btrfs_free_inode(trans, root, inode);
+        ret = btrfs_truncate_in_trans(trans, root, inode, 0);
         if (ret)
                 goto no_delete_lock;
+
         nr = trans->blocks_used;
+        clear_inode(inode);
 
         btrfs_end_transaction(trans, root);
         mutex_unlock(&root->fs_info->fs_mutex);
@@ -2190,7 +2205,8 @@ static void btrfs_truncate(struct inode *inode)
         btrfs_set_trans_block_group(trans, inode);
 
         /* FIXME, add redo link to tree so we don't leak on crash */
-        ret = btrfs_truncate_in_trans(trans, root, inode);
+        ret = btrfs_truncate_in_trans(trans, root, inode,
+                                      BTRFS_EXTENT_DATA_KEY);
         btrfs_update_inode(trans, root, inode);
         nr = trans->blocks_used;