f2fs: handle errors correctly during f2fs_reserve_block

The get_dnode_of_data nullifies inode and node page when error is occurred.

There are two cases that passes inode page into get_dnode_of_data().

1. make_empty_dir()
    -> get_new_data_page()
      -> f2fs_reserve_block(ipage)
	-> get_dnode_of_data()

2. f2fs_convert_inline_data()
    -> __f2fs_convert_inline_data()
      -> f2fs_reserve_block(ipage)
	-> get_dnode_of_data()

This patch adds correct error handling codes when get_dnode_of_data() returns
an error.

At first, f2fs_reserve_block() calls f2fs_put_dnode() whenever reserve_new_block
returns an error.
So, the rule of f2fs_reserve_block() is to nullify inode page when there is any
error internally.

Finally, two callers of f2fs_reserve_block() should call f2fs_put_dnode()
appropriately if they got an error since successful f2fs_reserve_block().

Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index fc7a28c..63d1902 100644 (file)
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -258,13 +258,16 @@ int f2fs_reserve_block(struct dnode_of_data *dn, pgoff_t index)
        bool need_put = dn->inode_page ? false : true;
        int err;
 
+       /* if inode_page exists, index should be zero */
+       f2fs_bug_on(!need_put && index);
+
        err = get_dnode_of_data(dn, index, ALLOC_NODE);
        if (err)
                return err;
+
        if (dn->data_blkaddr == NULL_ADDR)
                err = reserve_new_block(dn);
-
-       if (need_put)
+       if (err || need_put)
                f2fs_put_dnode(dn);
        return err;
 }
@@ -510,10 +513,10 @@ repeat:
  *
  * Also, caller should grab and release a rwsem by calling f2fs_lock_op() and
  * f2fs_unlock_op().
- * Note that, npage is set only by make_empty_dir.
+ * Note that, ipage is set only by make_empty_dir.
  */
 struct page *get_new_data_page(struct inode *inode,
-               struct page *npage, pgoff_t index, bool new_i_size)
+               struct page *ipage, pgoff_t index, bool new_i_size)
 {
        struct f2fs_sb_info *sbi = F2FS_SB(inode->i_sb);
        struct address_space *mapping = inode->i_mapping;
@@ -521,14 +524,16 @@ struct page *get_new_data_page(struct inode *inode,
        struct dnode_of_data dn;
        int err;
 
-       set_new_dnode(&dn, inode, npage, npage, 0);
+       set_new_dnode(&dn, inode, ipage, NULL, 0);
        err = f2fs_reserve_block(&dn, index);
        if (err)
                return ERR_PTR(err);
 repeat:
        page = grab_cache_page(mapping, index);
-       if (!page)
-               return ERR_PTR(-ENOMEM);
+       if (!page) {
+               err = -ENOMEM;
+               goto put_err;
+       }
 
        if (PageUptodate(page))
                return page;
@@ -540,11 +545,13 @@ repeat:
                err = f2fs_submit_page_bio(sbi, page, dn.data_blkaddr,
                                                                READ_SYNC);
                if (err)
-                       return ERR_PTR(err);
+                       goto put_err;
+
                lock_page(page);
                if (unlikely(!PageUptodate(page))) {
                        f2fs_put_page(page, 1);
-                       return ERR_PTR(-EIO);
+                       err = -EIO;
+                       goto put_err;
                }
                if (unlikely(page->mapping != mapping)) {
                        f2fs_put_page(page, 1);
@@ -560,6 +567,10 @@ repeat:
                mark_inode_dirty_sync(inode);
        }
        return page;
+
+put_err:
+       f2fs_put_dnode(&dn);
+       return ERR_PTR(err);
 }
 
 static int __allocate_data_block(struct dnode_of_data *dn)

diff --git a/fs/f2fs/dir.c b/fs/f2fs/dir.c
index 6da77e5..f815ca0 100644 (file)
--- a/fs/f2fs/dir.c
+++ b/fs/f2fs/dir.c
@@ -342,11 +342,11 @@ static struct page *init_inode_metadata(struct inode *inode,
 
                err = f2fs_init_acl(inode, dir, page);
                if (err)
-                       goto error;
+                       goto put_error;
 
                err = f2fs_init_security(inode, dir, name, page);
                if (err)
-                       goto error;
+                       goto put_error;
 
                wait_on_page_writeback(page);
        } else {
@@ -370,8 +370,9 @@ static struct page *init_inode_metadata(struct inode *inode,
        }
        return page;
 
-error:
+put_error:
        f2fs_put_page(page, 1);
+error:
        remove_inode_page(inode);
        return ERR_PTR(err);
 }

diff --git a/fs/f2fs/inline.c b/fs/f2fs/inline.c
index 2a756e5..688305a 100644 (file)
--- a/fs/f2fs/inline.c
+++ b/fs/f2fs/inline.c
@@ -81,10 +81,9 @@ static int __f2fs_convert_inline_data(struct inode *inode, struct page *page)
         * i_addr[0] is not used for inline data,
         * so reserving new block will not destroy inline data
         */
-       set_new_dnode(&dn, inode, ipage, ipage, 0);
+       set_new_dnode(&dn, inode, ipage, NULL, 0);
        err = f2fs_reserve_block(&dn, 0);
        if (err) {
-               f2fs_put_page(ipage, 1);
                f2fs_unlock_op(sbi);
                return err;
        }
@@ -111,9 +110,8 @@ static int __f2fs_convert_inline_data(struct inode *inode, struct page *page)
        stat_dec_inline_inode(inode);
 
        sync_inode_page(&dn);
-       f2fs_put_page(ipage, 1);
+       f2fs_put_dnode(&dn);
        f2fs_unlock_op(sbi);
-
        return err;
 }