Btrfs: Implement new dir index format

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

1 files changed, 121 insertions, 22 deletions

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 0e90315ea803..8d371d6fe551 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -872,6 +872,8 @@ void btrfs_read_locked_inode(struct inode *inode)
         inode->i_rdev = 0;
         rdev = btrfs_inode_rdev(leaf, inode_item);
 
+        BTRFS_I(inode)->index_cnt = (u64)-1;
+
         alloc_group_block = btrfs_inode_block_group(leaf, inode_item);
         BTRFS_I(inode)->block_group = btrfs_lookup_block_group(root->fs_info,
                                                        alloc_group_block);
@@ -993,6 +995,7 @@ static int btrfs_unlink_trans(struct btrfs_trans_handle *trans,
         struct extent_buffer *leaf;
         struct btrfs_dir_item *di;
         struct btrfs_key key;
+        u64 index;
 
         path = btrfs_alloc_path();
         if (!path) {
@@ -1017,8 +1020,19 @@ static int btrfs_unlink_trans(struct btrfs_trans_handle *trans,
                 goto err;
         btrfs_release_path(root, path);
 
+        ret = btrfs_del_inode_ref(trans, root, name, name_len,
+                                  dentry->d_inode->i_ino,
+                                  dentry->d_parent->d_inode->i_ino, &index);
+        if (ret) {
+                printk("failed to delete reference to %.*s, "
+                       "inode %lu parent %lu\n", name_len, name,
+                       dentry->d_inode->i_ino,
+                       dentry->d_parent->d_inode->i_ino);
+                goto err;
+        }
+
         di = btrfs_lookup_dir_index_item(trans, root, path, dir->i_ino,
-                                         key.objectid, name, name_len, -1);
+                                         index, name, name_len, -1);
         if (IS_ERR(di)) {
                 ret = PTR_ERR(di);
                 goto err;
@@ -1031,15 +1045,6 @@ static int btrfs_unlink_trans(struct btrfs_trans_handle *trans,
         btrfs_release_path(root, path);
 
         dentry->d_inode->i_ctime = dir->i_ctime;
-        ret = btrfs_del_inode_ref(trans, root, name, name_len,
-                                  dentry->d_inode->i_ino,
-                                  dentry->d_parent->d_inode->i_ino);
-        if (ret) {
-                printk("failed to delete reference to %.*s, "
-                       "inode %lu parent %lu\n", name_len, name,
-                       dentry->d_inode->i_ino,
-                       dentry->d_parent->d_inode->i_ino);
-        }
 err:
         btrfs_free_path(path);
         if (!ret) {
@@ -1625,6 +1630,7 @@ static int btrfs_init_locked_inode(struct inode *inode, void *p)
         BTRFS_I(inode)->root = args->root;
         BTRFS_I(inode)->delalloc_bytes = 0;
         BTRFS_I(inode)->disk_i_size = 0;
+        BTRFS_I(inode)->index_cnt = (u64)-1;
         extent_map_tree_init(&BTRFS_I(inode)->extent_tree, GFP_NOFS);
         extent_io_tree_init(&BTRFS_I(inode)->io_tree,
                              inode->i_mapping, GFP_NOFS);
@@ -1901,8 +1907,77 @@ void btrfs_dirty_inode(struct inode *inode)
         btrfs_end_transaction(trans, root);
 }
 
+static int btrfs_set_inode_index_count(struct inode *inode)
+{
+        struct btrfs_root *root = BTRFS_I(inode)->root;
+        struct btrfs_key key, found_key;
+        struct btrfs_path *path;
+        struct extent_buffer *leaf;
+        int ret;
+
+        key.objectid = inode->i_ino;
+        btrfs_set_key_type(&key, BTRFS_DIR_INDEX_KEY);
+        key.offset = (u64)-1;
+
+        path = btrfs_alloc_path();
+        if (!path)
+                return -ENOMEM;
+
+        ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
+        if (ret < 0)
+                goto out;
+        /* FIXME: we should be able to handle this */
+        if (ret == 0)
+                goto out;
+        ret = 0;
+
+        /*
+         * MAGIC NUMBER EXPLANATION:
+         * since we search a directory based on f_pos we have to start at 2
+         * since '.' and '..' have f_pos of 0 and 1 respectively, so everybody
+         * else has to start at 2
+         */
+        if (path->slots[0] == 0) {
+                BTRFS_I(inode)->index_cnt = 2;
+                goto out;
+        }
+
+        path->slots[0]--;
+
+        leaf = path->nodes[0];
+        btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0]);
+
+        if (found_key.objectid != inode->i_ino ||
+            btrfs_key_type(&found_key) != BTRFS_DIR_INDEX_KEY) {
+                BTRFS_I(inode)->index_cnt = 2;
+                goto out;
+        }
+
+        BTRFS_I(inode)->index_cnt = found_key.offset + 1;
+out:
+        btrfs_free_path(path);
+        return ret;
+}
+
+static int btrfs_set_inode_index(struct inode *dir, struct inode *inode)
+{
+        int ret = 0;
+
+        if (BTRFS_I(dir)->index_cnt == (u64)-1) {
+                ret = btrfs_set_inode_index_count(dir);
+                if (ret)
+                        return ret;
+        }
+
+        BTRFS_I(inode)->index = BTRFS_I(dir)->index_cnt;
+        BTRFS_I(dir)->index_cnt++;
+
+        return ret;
+}
+
 static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
                                      struct btrfs_root *root,
+                                     struct inode *dir,
                                      const char *name, int name_len,
                                      u64 ref_objectid,
                                      u64 objectid,
@@ -1928,6 +2003,20 @@ static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
         if (!inode)
                 return ERR_PTR(-ENOMEM);
 
+        if (dir) {
+                ret = btrfs_set_inode_index(dir, inode);
+                if (ret)
+                        return ERR_PTR(ret);
+        } else {
+                BTRFS_I(inode)->index = 0;
+        }
+        /*
+         * index_cnt is ignored for everything but a dir,
+         * btrfs_get_inode_index_count has an explanation for the magic
+         * number
+         */
+        BTRFS_I(inode)->index_cnt = 2;
+
         extent_map_tree_init(&BTRFS_I(inode)->extent_tree, GFP_NOFS);
         extent_io_tree_init(&BTRFS_I(inode)->io_tree,
                              inode->i_mapping, GFP_NOFS);
@@ -1984,6 +2073,7 @@ static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
         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);
+        btrfs_set_inode_ref_index(path->nodes[0], ref, BTRFS_I(inode)->index);
         ptr = (unsigned long)(ref + 1);
         write_extent_buffer(path->nodes[0], name, ptr, name_len);
 
@@ -1998,6 +2088,8 @@ static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
         insert_inode_hash(inode);
         return inode;
 fail:
+        if (dir)
+                BTRFS_I(dir)->index_cnt--;
         btrfs_free_path(path);
         return ERR_PTR(ret);
 }
@@ -2014,7 +2106,7 @@ static int btrfs_add_link(struct btrfs_trans_handle *trans,
         int ret;
         struct btrfs_key key;
         struct btrfs_root *root = BTRFS_I(dentry->d_parent->d_inode)->root;
-        struct inode *parent_inode;
+        struct inode *parent_inode = dentry->d_parent->d_inode;
 
         key.objectid = inode->i_ino;
         btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY);
@@ -2023,16 +2115,17 @@ static int btrfs_add_link(struct btrfs_trans_handle *trans,
         ret = btrfs_insert_dir_item(trans, root,
                                     dentry->d_name.name, dentry->d_name.len,
                                     dentry->d_parent->d_inode->i_ino,
-                                    &key, btrfs_inode_type(inode));
+                                    &key, btrfs_inode_type(inode),
+                                    BTRFS_I(inode)->index);
         if (ret == 0) {
                 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->i_ino,
+                                             BTRFS_I(inode)->index);
                 }
-                parent_inode = dentry->d_parent->d_inode;
                 btrfs_i_size_write(parent_inode, parent_inode->i_size +
                                    dentry->d_name.len * 2);
                 parent_inode->i_mtime = parent_inode->i_ctime = CURRENT_TIME;
@@ -2083,7 +2176,7 @@ static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
                 goto out_unlock;
         }
 
-        inode = btrfs_new_inode(trans, root, dentry->d_name.name,
+        inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
                                 dentry->d_name.len,
                                 dentry->d_parent->d_inode->i_ino, objectid,
                                 BTRFS_I(dir)->block_group, mode);
@@ -2138,7 +2231,7 @@ static int btrfs_create(struct inode *dir, struct dentry *dentry,
                 goto out_unlock;
         }
 
-        inode = btrfs_new_inode(trans, root, dentry->d_name.name,
+        inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
                                 dentry->d_name.len,
                                 dentry->d_parent->d_inode->i_ino,
                                 objectid, BTRFS_I(dir)->block_group, mode);
@@ -2203,10 +2296,15 @@ static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
         err = btrfs_check_free_space(root, 1, 0);
         if (err)
                 goto fail;
+        err = btrfs_set_inode_index(dir, inode);
+        if (err)
+                goto fail;
+
         trans = btrfs_start_transaction(root, 1);
 
         btrfs_set_trans_block_group(trans, dir);
         atomic_inc(&inode->i_count);
+
         err = btrfs_add_nondir(trans, dentry, inode, 1);
 
         if (err)
@@ -2258,7 +2356,7 @@ static int btrfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
                 goto out_unlock;
         }
 
-        inode = btrfs_new_inode(trans, root, dentry->d_name.name,
+        inode = btrfs_new_inode(trans, root, dir, dentry->d_name.name,
                                 dentry->d_name.len,
                                 dentry->d_parent->d_inode->i_ino, objectid,
                                 BTRFS_I(dir)->block_group, S_IFDIR | mode);
@@ -2886,9 +2984,8 @@ int btrfs_create_subvol_root(struct btrfs_root *new_root,
                 struct btrfs_block_group_cache *block_group)
 {
         struct inode *inode;
-        int ret;
 
-        inode = btrfs_new_inode(trans, new_root, "..", 2, new_dirid,
+        inode = btrfs_new_inode(trans, new_root, NULL, "..", 2, new_dirid,
                                 new_dirid, block_group, S_IFDIR | 0700);
         if (IS_ERR(inode))
                 return PTR_ERR(inode);
@@ -2896,8 +2993,6 @@ int btrfs_create_subvol_root(struct btrfs_root *new_root,
         inode->i_fop = &btrfs_dir_file_operations;
         new_root->inode = inode;
 
-        ret = btrfs_insert_inode_ref(trans, new_root, "..", 2, new_dirid,
-                                     new_dirid);
         inode->i_nlink = 1;
         btrfs_i_size_write(inode, 0);
 
@@ -3078,6 +3173,10 @@ static int btrfs_rename(struct inode * old_dir, struct dentry *old_dentry,
                 if (ret)
                         goto out_fail;
         }
+        ret = btrfs_set_inode_index(new_dir, old_inode);
+        if (ret)
+                goto out_fail;
+
         ret = btrfs_add_link(trans, new_dentry, old_inode, 1);
         if (ret)
                 goto out_fail;
@@ -3123,7 +3222,7 @@ static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
                 goto out_unlock;
         }
 
-        inode = btrfs_new_inode(trans, root, dentry->d_name.name,
+        inode = btrfs_new_inode(trans, root, dir, 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);