Btrfs: Audit callers and return codes to make sure -ENOSPC gets up the stack

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

1 files changed, 107 insertions, 58 deletions

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 94f1c28c25b9..6d031daa7779 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -212,7 +212,11 @@ static int btrfs_unlink_trans(struct btrfs_trans_handle *trans,
         struct btrfs_dir_item *di;
 
         path = btrfs_alloc_path();
-        BUG_ON(!path);
+        if (!path) {
+                ret = -ENOMEM;
+                goto err;
+        }
+
         di = btrfs_lookup_dir_item(trans, root, path, dir->i_ino,
                                     name, name_len, -1);
         if (IS_ERR(di)) {
@@ -225,7 +229,8 @@ static int btrfs_unlink_trans(struct btrfs_trans_handle *trans,
         }
         objectid = btrfs_disk_key_objectid(&di->location);
         ret = btrfs_delete_one_dir_name(trans, root, path, di);
-        BUG_ON(ret);
+        if (ret)
+                goto err;
         btrfs_release_path(root, path);
 
         di = btrfs_lookup_dir_index_item(trans, root, path, dir->i_ino,
@@ -239,7 +244,6 @@ static int btrfs_unlink_trans(struct btrfs_trans_handle *trans,
                 goto err;
         }
         ret = btrfs_delete_one_dir_name(trans, root, path, di);
-        BUG_ON(ret);
 
         dentry->d_inode->i_ctime = dir->i_ctime;
 err:
@@ -248,7 +252,7 @@ err:
                 dir->i_size -= name_len * 2;
                 btrfs_update_inode(trans, root, dir);
                 drop_nlink(dentry->d_inode);
-                btrfs_update_inode(trans, root, dentry->d_inode);
+                ret = btrfs_update_inode(trans, root, dentry->d_inode);
                 dir->i_sb->s_dirt = 1;
         }
         return ret;
@@ -359,9 +363,10 @@ static int btrfs_free_inode(struct btrfs_trans_handle *trans,
         BUG_ON(!path);
         ret = btrfs_lookup_inode(trans, root, path,
                                  &BTRFS_I(inode)->location, -1);
-        BUG_ON(ret);
-        ret = btrfs_del_item(trans, root, path);
-        BUG_ON(ret);
+        if (ret > 0)
+                ret = -ENOENT;
+        if (!ret)
+                ret = btrfs_del_item(trans, root, path);
         btrfs_free_path(path);
         return ret;
 }
@@ -516,7 +521,8 @@ static int btrfs_truncate_in_trans(struct btrfs_trans_handle *trans,
                 }
                 if (del_item) {
                         ret = btrfs_del_item(trans, root, path);
-                        BUG_ON(ret);
+                        if (ret)
+                                goto error;
                 } else {
                         break;
                 }
@@ -577,19 +583,22 @@ static int btrfs_truncate_page(struct address_space *mapping, loff_t from)
                                  page->index << PAGE_CACHE_SHIFT,
                                  (page->index + 1) << PAGE_CACHE_SHIFT,
                                  &alloc_hint);
-        BUG_ON(ret);
+        if (ret)
+                goto out;
         ret = btrfs_alloc_extent(trans, root, inode->i_ino, 1,
                                  alloc_hint, (u64)-1, &ins, 1);
-        BUG_ON(ret);
+        if (ret)
+                goto out;
         ret = btrfs_insert_file_extent(trans, root, inode->i_ino,
                                        page->index << PAGE_CACHE_SHIFT,
                                        ins.objectid, 1, 1);
-        BUG_ON(ret);
+        if (ret)
+                goto out;
         SetPageChecked(page);
         kaddr = kmap(page);
         memset(kaddr + offset, 0, PAGE_CACHE_SIZE - offset);
         flush_dcache_page(page);
-        btrfs_csum_file_block(trans, root, inode->i_ino,
+        ret = btrfs_csum_file_block(trans, root, inode->i_ino,
                               page->index << PAGE_CACHE_SHIFT,
                               kaddr, PAGE_CACHE_SIZE);
         kunmap(page);
@@ -633,9 +642,10 @@ static int btrfs_setattr(struct dentry *dentry, struct iattr *attr)
                 btrfs_set_trans_block_group(trans, inode);
                 err = btrfs_insert_file_extent(trans, root, inode->i_ino,
                                                pos, 0, 0, hole_size);
-                BUG_ON(err);
                 btrfs_end_transaction(trans, root);
                 mutex_unlock(&root->fs_info->fs_mutex);
+                if (err)
+                        return err;
         }
 out:
         err = inode_setattr(inode, attr);
@@ -657,12 +667,20 @@ 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);
-        BUG_ON(ret);
-        btrfs_free_inode(trans, root, inode);
+        if (ret)
+                goto no_delete_lock;
+        ret = btrfs_free_inode(trans, root, inode);
+        if (ret)
+                goto no_delete_lock;
         btrfs_end_transaction(trans, root);
         mutex_unlock(&root->fs_info->fs_mutex);
         btrfs_btree_balance_dirty(root);
         return;
+
+no_delete_lock:
+        btrfs_end_transaction(trans, root);
+        mutex_unlock(&root->fs_info->fs_mutex);
+        btrfs_btree_balance_dirty(root);
 no_delete:
         clear_inode(inode);
 }
@@ -946,7 +964,7 @@ int btrfs_write_inode(struct inode *inode, int wait)
 }
 
 /*
- * This is somewhat expense, updating the tree every time the
+ * This is somewhat expensive, updating the tree every time the
  * inode changes.  But, it is most likely to find the inode in cache.
  * FIXME, needs more benchmarking...there are no reasons other than performance
  * to keep or drop this code.
@@ -1002,8 +1020,8 @@ static struct inode *btrfs_new_inode(struct btrfs_trans_handle *trans,
         btrfs_set_key_type(location, BTRFS_INODE_ITEM_KEY);
 
         ret = btrfs_insert_inode(trans, root, objectid, &inode_item);
-        BUG_ON(ret);
-
+        if (ret)
+                return ERR_PTR(ret);
         insert_inode_hash(inode);
         return inode;
 }
@@ -1121,7 +1139,9 @@ static int btrfs_link(struct dentry *old_dentry, struct inode *dir,
                 drop_inode = 1;
         dir->i_sb->s_dirt = 1;
         btrfs_update_inode_block_group(trans, dir);
-        btrfs_update_inode(trans, root, inode);
+        err = btrfs_update_inode(trans, root, inode);
+        if (err)
+                drop_inode = 1;
 
         btrfs_end_transaction(trans, root);
         mutex_unlock(&root->fs_info->fs_mutex);
@@ -1349,17 +1369,26 @@ not_found:
                 ret = btrfs_alloc_extent(trans, root, inode->i_ino,
                                          1, alloc_hint, (u64)-1,
                                          &ins, 1);
-                BUG_ON(ret);
+                if (ret) {
+                        err = ret;
+                        goto out;
+                }
                 ret = btrfs_insert_file_extent(trans, root, inode->i_ino,
                                                iblock << inode->i_blkbits,
                                                ins.objectid, ins.offset,
                                                ins.offset);
-                BUG_ON(ret);
+                if (ret) {
+                        err = ret;
+                        goto out;
+                }
                 btrfs_map_bh_to_logical(root, result, ins.objectid);
         }
 out:
-        if (trans)
-                err = btrfs_end_transaction(trans, root);
+        if (trans) {
+                ret = btrfs_end_transaction(trans, root);
+                if (!err)
+                        err = ret;
+        }
         btrfs_free_path(path);
         return err;
 }
@@ -1375,8 +1404,8 @@ int btrfs_get_block(struct inode *inode, sector_t iblock,
         return err;
 }
 
-int btrfs_get_block_csum(struct inode *inode, sector_t iblock,
-                    struct buffer_head *result, int create)
+static int btrfs_get_block_csum(struct inode *inode, sector_t iblock,
+                                struct buffer_head *result, int create)
 {
         int ret;
         struct btrfs_root *root = BTRFS_I(inode)->root;
@@ -1397,7 +1426,7 @@ int btrfs_get_block_csum(struct inode *inode, sector_t iblock,
                 /* a csum that isn't present is a preallocated region. */
                 if (ret == -ENOENT || ret == -EFBIG)
                         ret = 0;
-                result->b_private = 0;
+                result->b_private = NULL;
                 goto out;
         }
         memcpy((char *)&result->b_private, &item->csum, BTRFS_CRC32_SIZE);
@@ -1736,11 +1765,10 @@ static int __btrfs_write_full_page(struct inode *inode, struct page *page,
                         trans = btrfs_start_transaction(root, 1);
                         btrfs_set_trans_block_group(trans, inode);
                         kaddr = kmap(page);
-                        ret = btrfs_csum_file_block(trans, root, inode->i_ino,
+                        btrfs_csum_file_block(trans, root, inode->i_ino,
                                                     off, kaddr + bh_offset(bh),
                                                     bh->b_size);
                         kunmap(page);
-                        BUG_ON(ret);
                         ret = btrfs_end_transaction(trans, root);
                         BUG_ON(ret);
                         mutex_unlock(&root->fs_info->fs_mutex);
@@ -1930,7 +1958,6 @@ static void btrfs_truncate(struct inode *inode)
 
         /* FIXME, add redo link to tree so we don't leak on crash */
         ret = btrfs_truncate_in_trans(trans, root, inode);
-        BUG_ON(ret);
         btrfs_update_inode(trans, root, inode);
         ret = btrfs_end_transaction(trans, root);
         BUG_ON(ret);
@@ -1970,6 +1997,7 @@ static int create_subvol(struct btrfs_root *root, char *name, int namelen)
         struct inode *inode;
         struct inode *dir;
         int ret;
+        int err;
         u64 objectid;
         u64 new_dirid = BTRFS_FIRST_FREE_OBJECTID;
 
@@ -1978,8 +2006,8 @@ static int create_subvol(struct btrfs_root *root, char *name, int namelen)
         BUG_ON(!trans);
 
         subvol = btrfs_alloc_free_block(trans, root, 0);
-        if (subvol == NULL)
-                return -ENOSPC;
+        if (IS_ERR(subvol))
+                return PTR_ERR(subvol);
         leaf = btrfs_buffer_leaf(subvol);
         btrfs_set_header_nritems(&leaf->header, 0);
         btrfs_set_header_level(&leaf->header, 0);
@@ -2005,7 +2033,8 @@ static int create_subvol(struct btrfs_root *root, char *name, int namelen)
 
         ret = btrfs_find_free_objectid(trans, root->fs_info->tree_root,
                                        0, &objectid);
-        BUG_ON(ret);
+        if (ret)
+                goto fail;
 
         btrfs_set_root_dirid(&root_item, new_dirid);
 
@@ -2015,7 +2044,8 @@ static int create_subvol(struct btrfs_root *root, char *name, int namelen)
         btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY);
         ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
                                 &root_item);
-        BUG_ON(ret);
+        if (ret)
+                goto fail;
 
         /*
          * insert the directory item
@@ -2025,10 +2055,12 @@ static int create_subvol(struct btrfs_root *root, char *name, int namelen)
         ret = btrfs_insert_dir_item(trans, root->fs_info->tree_root,
                                     name, namelen, dir->i_ino, &key,
                                     BTRFS_FT_DIR);
-        BUG_ON(ret);
+        if (ret)
+                goto fail;
 
         ret = btrfs_commit_transaction(trans, root);
-        BUG_ON(ret);
+        if (ret)
+                goto fail_commit;
 
         new_root = btrfs_read_fs_root(root->fs_info, &key);
         BUG_ON(!new_root);
@@ -2038,24 +2070,29 @@ static int create_subvol(struct btrfs_root *root, char *name, int namelen)
 
         inode = btrfs_new_inode(trans, new_root, new_dirid,
                                 BTRFS_I(dir)->block_group, S_IFDIR | 0700);
+        if (IS_ERR(inode))
+                goto fail;
         inode->i_op = &btrfs_dir_inode_operations;
         inode->i_fop = &btrfs_dir_file_operations;
         new_root->inode = inode;
 
         ret = btrfs_make_empty_dir(trans, new_root, new_dirid, new_dirid);
-        BUG_ON(ret);
+        if (ret)
+                goto fail;
 
         inode->i_nlink = 1;
         inode->i_size = 6;
         ret = btrfs_update_inode(trans, new_root, inode);
-        BUG_ON(ret);
-
-        ret = btrfs_commit_transaction(trans, new_root);
-        BUG_ON(ret);
-
+        if (ret)
+                goto fail;
+fail:
+        err = btrfs_commit_transaction(trans, root);
+        if (err && !ret)
+                ret = err;
+fail_commit:
         mutex_unlock(&root->fs_info->fs_mutex);
         btrfs_btree_balance_dirty(root);
-        return 0;
+        return ret;
 }
 
 static int create_snapshot(struct btrfs_root *root, char *name, int namelen)
@@ -2064,6 +2101,7 @@ static int create_snapshot(struct btrfs_root *root, char *name, int namelen)
         struct btrfs_key key;
         struct btrfs_root_item new_root_item;
         int ret;
+        int err;
         u64 objectid;
 
         if (!root->ref_cows)
@@ -2074,11 +2112,13 @@ static int create_snapshot(struct btrfs_root *root, char *name, int namelen)
         BUG_ON(!trans);
 
         ret = btrfs_update_inode(trans, root, root->inode);
-        BUG_ON(ret);
+        if (ret)
+                goto fail;
 
         ret = btrfs_find_free_objectid(trans, root->fs_info->tree_root,
                                        0, &objectid);
-        BUG_ON(ret);
+        if (ret)
+                goto fail;
 
         memcpy(&new_root_item, &root->root_item,
                sizeof(new_root_item));
@@ -2091,7 +2131,8 @@ static int create_snapshot(struct btrfs_root *root, char *name, int namelen)
 
         ret = btrfs_insert_root(trans, root->fs_info->tree_root, &key,
                                 &new_root_item);
-        BUG_ON(ret);
+        if (ret)
+                goto fail;
 
         /*
          * insert the directory item
@@ -2102,16 +2143,20 @@ static int create_snapshot(struct btrfs_root *root, char *name, int namelen)
                                     root->fs_info->sb->s_root->d_inode->i_ino,
                                     &key, BTRFS_FT_DIR);
 
-        BUG_ON(ret);
+        if (ret)
+                goto fail;
 
         ret = btrfs_inc_root_ref(trans, root);
-        BUG_ON(ret);
+        if (ret)
+                goto fail;
 
-        ret = btrfs_commit_transaction(trans, root);
-        BUG_ON(ret);
+fail:
+        err = btrfs_commit_transaction(trans, root);
+        if (err && !ret)
+                ret = err;
         mutex_unlock(&root->fs_info->fs_mutex);
         btrfs_btree_balance_dirty(root);
-        return 0;
+        return ret;
 }
 
 int btrfs_ioctl(struct inode *inode, struct file *filp, unsigned int
@@ -2148,12 +2193,13 @@ int btrfs_ioctl(struct inode *inode, struct file *filp, unsigned int
                 btrfs_free_path(path);
                 if (di && !IS_ERR(di))
                         return -EEXIST;
+                if (IS_ERR(di))
+                        return PTR_ERR(di);
 
                 if (root == root->fs_info->tree_root)
                         ret = create_subvol(root, vol_args.name, namelen);
                 else
                         ret = create_snapshot(root, vol_args.name, namelen);
-                WARN_ON(ret);
                 break;
         default:
                 return -ENOTTY;
@@ -2316,7 +2362,6 @@ static int btrfs_rename(struct inode * old_dir, struct dentry *old_dentry,
                 old_parent_oid = btrfs_disk_key_objectid(&di->location);
                 ret = btrfs_del_item(trans, root, path);
                 if (ret) {
-                        ret = -EIO;
                         goto out_fail;
                 }
                 btrfs_release_path(root, path);
@@ -2335,7 +2380,6 @@ static int btrfs_rename(struct inode * old_dir, struct dentry *old_dentry,
                 }
                 ret = btrfs_del_item(trans, root, path);
                 if (ret) {
-                        ret = -EIO;
                         goto out_fail;
                 }
                 btrfs_release_path(root, path);
@@ -2361,7 +2405,9 @@ static int btrfs_rename(struct inode * old_dir, struct dentry *old_dentry,
                         clear_nlink(new_inode);
                 else
                         drop_nlink(new_inode);
-                btrfs_update_inode(trans, root, new_inode);
+                ret = btrfs_update_inode(trans, root, new_inode);
+                if (ret)
+                        goto out_fail;
         }
         ret = btrfs_add_link(trans, new_dentry, old_inode);
         if (ret)
@@ -2433,7 +2479,10 @@ static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
         datasize = btrfs_file_extent_calc_inline_size(name_len);
         err = btrfs_insert_empty_item(trans, root, path, &key,
                                       datasize);
-        BUG_ON(err);
+        if (err) {
+                drop_inode = 1;
+                goto out_unlock;
+        }
         ei = btrfs_item_ptr(btrfs_buffer_leaf(path->nodes[0]),
                path->slots[0], struct btrfs_file_extent_item);
         btrfs_set_file_extent_generation(ei, trans->transid);
@@ -2447,13 +2496,13 @@ static int btrfs_symlink(struct inode *dir, struct dentry *dentry,
         inode->i_op = &btrfs_symlink_inode_operations;
         inode->i_mapping->a_ops = &btrfs_symlink_aops;
         inode->i_size = name_len - 1;
-        btrfs_update_inode(trans, root, inode);
-        err = 0;
+        err = btrfs_update_inode(trans, root, inode);
+        if (err)
+                drop_inode = 1;
 
 out_unlock:
         btrfs_end_transaction(trans, root);
         mutex_unlock(&root->fs_info->fs_mutex);
-
         if (drop_inode) {
                 inode_dec_link_count(inode);
                 iput(inode);