Btrfs: Implement mknod

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

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index d75ca5cf59b180cc66a8c86857135a26edbeabda..f95cf5d4a69d2c209cdf8e20779c63f62377705d 100644 (file)
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -46,6 +46,7 @@ struct btrfs_iget_args {
 static struct inode_operations btrfs_dir_inode_operations;
 static struct inode_operations btrfs_symlink_inode_operations;
 static struct inode_operations btrfs_dir_ro_inode_operations;
+static struct inode_operations btrfs_special_inode_operations;
 static struct inode_operations btrfs_file_inode_operations;
 static struct address_space_operations btrfs_aops;
 static struct address_space_operations btrfs_symlink_aops;
@@ -75,6 +76,7 @@ void btrfs_read_locked_inode(struct inode *inode)
        struct btrfs_root *root = BTRFS_I(inode)->root;
        struct btrfs_key location;
        u64 alloc_group_block;
+       u32 rdev;
        int ret;
 
        path = btrfs_alloc_path();
@@ -104,6 +106,8 @@ void btrfs_read_locked_inode(struct inode *inode)
        inode->i_ctime.tv_nsec = btrfs_timespec_nsec(&inode_item->ctime);
        inode->i_blocks = btrfs_inode_nblocks(inode_item);
        inode->i_generation = btrfs_inode_generation(inode_item);
+       inode->i_rdev = 0;
+       rdev = btrfs_inode_rdev(inode_item);
        alloc_group_block = btrfs_inode_block_group(inode_item);
        BTRFS_I(inode)->block_group = btrfs_lookup_block_group(root->fs_info,
                                                       alloc_group_block);
@@ -114,12 +118,6 @@ void btrfs_read_locked_inode(struct inode *inode)
        mutex_unlock(&root->fs_info->fs_mutex);
 
        switch (inode->i_mode & S_IFMT) {
-#if 0
-       default:
-               init_special_inode(inode, inode->i_mode,
-                                  btrfs_inode_rdev(inode_item));
-               break;
-#endif
        case S_IFREG:
                inode->i_mapping->a_ops = &btrfs_aops;
                inode->i_fop = &btrfs_file_operations;
@@ -136,6 +134,9 @@ void btrfs_read_locked_inode(struct inode *inode)
                inode->i_op = &btrfs_symlink_inode_operations;
                inode->i_mapping->a_ops = &btrfs_symlink_aops;
                break;
+       default:
+               init_special_inode(inode, inode->i_mode, rdev);
+               break;
        }
        return;
 
@@ -162,6 +163,7 @@ static void fill_inode_item(struct btrfs_inode_item *item,
        btrfs_set_timespec_nsec(&item->ctime, inode->i_ctime.tv_nsec);
        btrfs_set_inode_nblocks(item, inode->i_blocks);
        btrfs_set_inode_generation(item, inode->i_generation);
+       btrfs_set_inode_rdev(item, inode->i_rdev);
        btrfs_set_inode_block_group(item,
                                    BTRFS_I(inode)->block_group->key.objectid);
 }
@@ -1070,6 +1072,58 @@ static int btrfs_add_nondir(struct btrfs_trans_handle *trans,
        return err;
 }
 
+static int btrfs_mknod(struct inode *dir, struct dentry *dentry,
+                       int mode, dev_t rdev)
+{
+       struct btrfs_trans_handle *trans;
+       struct btrfs_root *root = BTRFS_I(dir)->root;
+       struct inode *inode;
+       int err;
+       int drop_inode = 0;
+       u64 objectid;
+
+       if (!new_valid_dev(rdev))
+               return -EINVAL;
+
+       mutex_lock(&root->fs_info->fs_mutex);
+       trans = btrfs_start_transaction(root, 1);
+       btrfs_set_trans_block_group(trans, dir);
+
+       err = btrfs_find_free_objectid(trans, root, dir->i_ino, &objectid);
+       if (err) {
+               err = -ENOSPC;
+               goto out_unlock;
+       }
+
+       inode = btrfs_new_inode(trans, root, 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);
+       if (err)
+               drop_inode = 1;
+       else {
+               inode->i_op = &btrfs_special_inode_operations;
+               init_special_inode(inode, inode->i_mode, rdev);
+       }
+       dir->i_sb->s_dirt = 1;
+       btrfs_update_inode_block_group(trans, inode);
+       btrfs_update_inode_block_group(trans, dir);
+out_unlock:
+       btrfs_end_transaction(trans, root);
+       mutex_unlock(&root->fs_info->fs_mutex);
+
+       if (drop_inode) {
+               inode_dec_link_count(inode);
+               iput(inode);
+       }
+       btrfs_btree_balance_dirty(root);
+       return err;
+}
+
 static int btrfs_create(struct inode *dir, struct dentry *dentry,
                        int mode, struct nameidata *nd)
 {
@@ -2526,6 +2580,7 @@ static struct inode_operations btrfs_dir_inode_operations = {
        .rename         = btrfs_rename,
        .symlink        = btrfs_symlink,
        .setattr        = btrfs_setattr,
+       .mknod          = btrfs_mknod,
 };
 
 static struct inode_operations btrfs_dir_ro_inode_operations = {
@@ -2562,6 +2617,11 @@ static struct inode_operations btrfs_file_inode_operations = {
        .setattr        = btrfs_setattr,
 };
 
+static struct inode_operations btrfs_special_inode_operations = {
+       .getattr        = btrfs_getattr,
+       .setattr        = btrfs_setattr,
+};
+
 static struct inode_operations btrfs_symlink_inode_operations = {
        .readlink       = generic_readlink,
        .follow_link    = page_follow_link_light,