Btrfs: Add inode item and backref in one insert, reducing cpu usage

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

3 files changed, 102 insertions, 39 deletions

diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index 84ad53e06b3a..fb2e2bd506c8 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -2332,27 +2332,34 @@ int btrfs_extend_item(struct btrfs_trans_handle *trans,
  * Given a key and some data, insert an item into the tree.
  * This does all the path init required, making room in the tree if needed.
  */
-int btrfs_insert_empty_item(struct btrfs_trans_handle *trans,
+int btrfs_insert_empty_items(struct btrfs_trans_handle *trans,
                             struct btrfs_root *root,
                             struct btrfs_path *path,
-                            struct btrfs_key *cpu_key, u32 data_size)
+                            struct btrfs_key *cpu_key, u32 *data_size,
+                            int nr)
 {
         struct extent_buffer *leaf;
         struct btrfs_item *item;
         int ret = 0;
         int slot;
         int slot_orig;
+        int i;
         u32 nritems;
+        u32 total_size = 0;
+        u32 total_data = 0;
         unsigned int data_end;
         struct btrfs_disk_key disk_key;
 
-        btrfs_cpu_key_to_disk(&disk_key, cpu_key);
+        for (i = 0; i < nr; i++) {
+                total_data += data_size[i];
+        }
 
         /* create a root if there isn't one */
         if (!root->node)
                 BUG();
 
-        ret = btrfs_search_slot(trans, root, cpu_key, path, data_size, 1);
+        total_size = total_data + (nr - 1) * sizeof(struct btrfs_item);
+        ret = btrfs_search_slot(trans, root, cpu_key, path, total_size, 1);
         if (ret == 0) {
                 return -EEXIST;
         }
@@ -2366,10 +2373,10 @@ int btrfs_insert_empty_item(struct btrfs_trans_handle *trans,
         data_end = leaf_data_end(root, leaf);
 
         if (btrfs_leaf_free_space(root, leaf) <
-            sizeof(struct btrfs_item) + data_size) {
+            sizeof(struct btrfs_item) + total_size) {
                 btrfs_print_leaf(root, leaf);
                 printk("not enough freespace need %u have %d\n",
-                       data_size, btrfs_leaf_free_space(root, leaf));
+                       total_size, btrfs_leaf_free_space(root, leaf));
                 BUG();
         }
 
@@ -2404,7 +2411,7 @@ int btrfs_insert_empty_item(struct btrfs_trans_handle *trans,
                         }
 
                         ioff = btrfs_item_offset(leaf, item);
-                        btrfs_set_item_offset(leaf, item, ioff - data_size);
+                        btrfs_set_item_offset(leaf, item, ioff - total_data);
                 }
                 if (leaf->map_token) {
                         unmap_extent_buffer(leaf, leaf->map_token, KM_USER1);
@@ -2412,23 +2419,27 @@ int btrfs_insert_empty_item(struct btrfs_trans_handle *trans,
                 }
 
                 /* shift the items */
-                memmove_extent_buffer(leaf, btrfs_item_nr_offset(slot + 1),
+                memmove_extent_buffer(leaf, btrfs_item_nr_offset(slot + nr),
                               btrfs_item_nr_offset(slot),
                               (nritems - slot) * sizeof(struct btrfs_item));
 
                 /* shift the data */
                 memmove_extent_buffer(leaf, btrfs_leaf_data(leaf) +
-                              data_end - data_size, btrfs_leaf_data(leaf) +
+                              data_end - total_data, btrfs_leaf_data(leaf) +
                               data_end, old_data - data_end);
                 data_end = old_data;
         }
 
         /* setup the item for the new data */
-        btrfs_set_item_key(leaf, &disk_key, slot);
-        item = btrfs_item_nr(leaf, slot);
-        btrfs_set_item_offset(leaf, item, data_end - data_size);
-        btrfs_set_item_size(leaf, item, data_size);
-        btrfs_set_header_nritems(leaf, nritems + 1);
+        for (i = 0; i < nr; i++) {
+                btrfs_cpu_key_to_disk(&disk_key, cpu_key + i);
+                btrfs_set_item_key(leaf, &disk_key, slot + i);
+                item = btrfs_item_nr(leaf, slot + i);
+                btrfs_set_item_offset(leaf, item, data_end - data_size[i]);
+                data_end -= data_size[i];
+                btrfs_set_item_size(leaf, item, data_size[i]);
+        }
+        btrfs_set_header_nritems(leaf, nritems + nr);
         btrfs_mark_buffer_dirty(leaf);
 
         ret = 0;
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 098cf0883150..127c86f795d0 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -1050,9 +1050,20 @@ static inline int btrfs_del_item(struct btrfs_trans_handle *trans,
 
 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
-                            *root, struct btrfs_path *path, struct btrfs_key
-                            *cpu_key, u32 data_size);
+int btrfs_insert_empty_items(struct btrfs_trans_handle *trans,
+                             struct btrfs_root *root,
+                             struct btrfs_path *path,
+                             struct btrfs_key *cpu_key, u32 *data_size, int nr);
+
+static inline int btrfs_insert_empty_item(struct btrfs_trans_handle *trans,
+                                          struct btrfs_root *root,
+                                          struct btrfs_path *path,
+                                          struct btrfs_key *key,
+                                          u32 data_size)
+{
+        return btrfs_insert_empty_items(trans, root, path, key, &data_size, 1);
+}
+
 int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path);
 int btrfs_prev_leaf(struct btrfs_root *root, struct btrfs_path *path);
 int btrfs_leaf_free_space(struct btrfs_root *root, struct extent_buffer *leaf);
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 0a2fe51c4127..413b1012de53 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -1500,6 +1500,8 @@ void btrfs_dirty_inode(struct inode *inode)
 
 static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
                                      struct btrfs_root *root,
+                                     const char *name, int name_len,
+                                     u64 ref_objectid,
                                      u64 objectid,
                                      struct btrfs_block_group_cache *group,
                                      int mode)
@@ -1508,6 +1510,10 @@ static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
         struct btrfs_inode_item *inode_item;
         struct btrfs_key *location;
         struct btrfs_path *path;
+        struct btrfs_inode_ref *ref;
+        struct btrfs_key key[2];
+        u32 sizes[2];
+        unsigned long ptr;
         int ret;
         int owner;
 
@@ -1530,10 +1536,25 @@ static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
         group = btrfs_find_block_group(root, group, 0, 0, owner);
         BTRFS_I(inode)->block_group = group;
         BTRFS_I(inode)->flags = 0;
-        ret = btrfs_insert_empty_inode(trans, root, path, objectid);
-        if (ret)
+
+        key[0].objectid = objectid;
+        btrfs_set_key_type(&key[0], BTRFS_INODE_ITEM_KEY);
+        key[0].offset = 0;
+
+        key[1].objectid = objectid;
+        btrfs_set_key_type(&key[1], BTRFS_INODE_REF_KEY);
+        key[1].offset = ref_objectid;
+
+        sizes[0] = sizeof(struct btrfs_inode_item);
+        sizes[1] = name_len + sizeof(*ref);
+
+        ret = btrfs_insert_empty_items(trans, root, path, key, sizes, 2);
+        if (ret != 0)
                 goto fail;
 
+        if (objectid > root->highest_inode)
+                root->highest_inode = objectid;
+
         inode->i_uid = current->fsuid;
         inode->i_gid = current->fsgid;
         inode->i_mode = mode;
@@ -1543,6 +1564,13 @@ static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
         inode_item = btrfs_item_ptr(path->nodes[0], path->slots[0],
                                   struct btrfs_inode_item);
         fill_inode_item(path->nodes[0], inode_item, inode);
+
+        ref = btrfs_item_ptr(path->nodes[0], path->slots[0] + 1,
+                             struct btrfs_inode_ref);
+        btrfs_set_inode_ref_name_len(path->nodes[0], ref, name_len);
+        ptr = (unsigned long)(ref + 1);
+        write_extent_buffer(path->nodes[0], name, ptr, name_len);
+
         btrfs_mark_buffer_dirty(path->nodes[0]);
         btrfs_free_path(path);
 
@@ -1564,7 +1592,8 @@ static inline u8 btrfs_inode_type(struct inode *inode)
 }
 
 static int btrfs_add_link(struct btrfs_trans_handle *trans,
-                            struct dentry *dentry, struct inode *inode)
+                            struct dentry *dentry, struct inode *inode,
+                            int add_backref)
 {
         int ret;
         struct btrfs_key key;
@@ -1580,11 +1609,13 @@ static int btrfs_add_link(struct btrfs_trans_handle *trans,
                                     dentry->d_parent->d_inode->i_ino,
                                     &key, btrfs_inode_type(inode));
         if (ret == 0) {
-                ret = btrfs_insert_inode_ref(trans, root,
-                                     dentry->d_name.name,
-                                     dentry->d_name.len,
-                                     inode->i_ino,
-                                     dentry->d_parent->d_inode->i_ino);
+                if (add_backref) {
+                        ret = btrfs_insert_inode_ref(trans, root,
+                                             dentry->d_name.name,
+                                             dentry->d_name.len,
+                                             inode->i_ino,
+                                             dentry->d_parent->d_inode->i_ino);
+                }
                 parent_inode = dentry->d_parent->d_inode;
                 parent_inode->i_size += dentry->d_name.len * 2;
                 parent_inode->i_mtime = parent_inode->i_ctime = CURRENT_TIME;
@@ -1595,9 +1626,10 @@ static int btrfs_add_link(struct btrfs_trans_handle *trans,
 }
 
 static int btrfs_add_nondir(struct btrfs_trans_handle *trans,
-                            struct dentry *dentry, struct inode *inode)
+                            struct dentry *dentry, struct inode *inode,
+                            int backref)
 {
-        int err = btrfs_add_link(trans, dentry, inode);
+        int err = btrfs_add_link(trans, dentry, inode, backref);
         if (!err) {
                 d_instantiate(dentry, inode);
                 return 0;
@@ -1635,14 +1667,16 @@ static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
                 goto out_unlock;
         }
 
-        inode = btrfs_new_inode(trans, root, objectid,
+        inode = btrfs_new_inode(trans, root, dentry->d_name.name,
+                                dentry->d_name.len,
+                                dentry->d_parent->d_inode->i_ino, objectid,
                                 BTRFS_I(dir)->block_group, mode);
         err = PTR_ERR(inode);
         if (IS_ERR(inode))
                 goto out_unlock;
 
         btrfs_set_trans_block_group(trans, inode);
-        err = btrfs_add_nondir(trans, dentry, inode);
+        err = btrfs_add_nondir(trans, dentry, inode, 0);
         if (err)
                 drop_inode = 1;
         else {
@@ -1692,14 +1726,16 @@ static int btrfs_create(struct inode *dir, struct dentry *dentry,
                 goto out_unlock;
         }
 
-        inode = btrfs_new_inode(trans, root, objectid,
-                                BTRFS_I(dir)->block_group, mode);
+        inode = btrfs_new_inode(trans, root, dentry->d_name.name,
+                                dentry->d_name.len,
+                                dentry->d_parent->d_inode->i_ino,
+                                objectid, BTRFS_I(dir)->block_group, mode);
         err = PTR_ERR(inode);
         if (IS_ERR(inode))
                 goto out_unlock;
 
         btrfs_set_trans_block_group(trans, inode);
-        err = btrfs_add_nondir(trans, dentry, inode);
+        err = btrfs_add_nondir(trans, dentry, inode, 0);
         if (err)
                 drop_inode = 1;
         else {
@@ -1755,7 +1791,7 @@ static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
 
         btrfs_set_trans_block_group(trans, dir);
         atomic_inc(&inode->i_count);
-        err = btrfs_add_nondir(trans, dentry, inode);
+        err = btrfs_add_nondir(trans, dentry, inode, 1);
 
         if (err)
                 drop_inode = 1;
@@ -1810,7 +1846,9 @@ static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
                 goto out_unlock;
         }
 
-        inode = btrfs_new_inode(trans, root, objectid,
+        inode = btrfs_new_inode(trans, root, dentry->d_name.name,
+                                dentry->d_name.len,
+                                dentry->d_parent->d_inode->i_ino, objectid,
                                 BTRFS_I(dir)->block_group, S_IFDIR | mode);
         if (IS_ERR(inode)) {
                 err = PTR_ERR(inode);
@@ -1827,7 +1865,7 @@ static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
         if (err)
                 goto out_fail;
 
-        err = btrfs_add_link(trans, dentry, inode);
+        err = btrfs_add_link(trans, dentry, inode, 0);
         if (err)
                 goto out_fail;
 
@@ -2320,7 +2358,8 @@ static int noinline create_subvol(struct btrfs_root *root, char *name,
         trans = btrfs_start_transaction(new_root, 1);
         BUG_ON(!trans);
 
-        inode = btrfs_new_inode(trans, new_root, new_dirid,
+        inode = btrfs_new_inode(trans, new_root, "..", 2, new_dirid,
+                                new_dirid,
                                 BTRFS_I(dir)->block_group, S_IFDIR | 0700);
         if (IS_ERR(inode))
                 goto fail;
@@ -2817,7 +2856,7 @@ static int btrfs_rename(struct inode * old_dir, struct dentry *old_dentry,
                 if (ret)
                         goto out_fail;
         }
-        ret = btrfs_add_link(trans, new_dentry, old_inode);
+        ret = btrfs_add_link(trans, new_dentry, old_inode, 1);
         if (ret)
                 goto out_fail;
 
@@ -2865,14 +2904,16 @@ static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
                 goto out_unlock;
         }
 
-        inode = btrfs_new_inode(trans, root, objectid,
+        inode = btrfs_new_inode(trans, root, dentry->d_name.name,
+                                dentry->d_name.len,
+                                dentry->d_parent->d_inode->i_ino, objectid,
                                 BTRFS_I(dir)->block_group, S_IFLNK|S_IRWXUGO);
         err = PTR_ERR(inode);
         if (IS_ERR(inode))
                 goto out_unlock;
 
         btrfs_set_trans_block_group(trans, inode);
-        err = btrfs_add_nondir(trans, dentry, inode);
+        err = btrfs_add_nondir(trans, dentry, inode, 0);
         if (err)
                 drop_inode = 1;
         else {