f2fs: introduce f2fs_write_failed to handle error case when write

When we fail in ->write_begin()/->direct_IO(), our allocated node block in disk
and page cache are still kept, despite these may not be used again.

This patch introduce f2fs_write_failed() to handle the error case of these two
interfaces, it will truncate page cache and blocks of this file according to
i_size.

Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 2eb2764..05154d6 100644 (file)
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -914,6 +914,16 @@ skip_write:
        return 0;
 }
 
+static void f2fs_write_failed(struct address_space *mapping, loff_t to)
+{
+       struct inode *inode = mapping->host;
+
+       if (to > inode->i_size) {
+               truncate_pagecache(inode, inode->i_size);
+               truncate_blocks(inode, inode->i_size);
+       }
+}
+
 static int f2fs_write_begin(struct file *file, struct address_space *mapping,
                loff_t pos, unsigned len, unsigned flags,
                struct page **pagep, void **fsdata)
@@ -931,11 +941,13 @@ static int f2fs_write_begin(struct file *file, struct address_space *mapping,
 repeat:
        err = f2fs_convert_inline_data(inode, pos + len);
        if (err)
-               return err;
+               goto fail;
 
        page = grab_cache_page_write_begin(mapping, index, flags);
-       if (!page)
-               return -ENOMEM;
+       if (!page) {
+               err = -ENOMEM;
+               goto fail;
+       }
 
        /* to avoid latency during memory pressure */
        unlock_page(page);
@@ -949,10 +961,9 @@ repeat:
        set_new_dnode(&dn, inode, NULL, NULL, 0);
        err = f2fs_reserve_block(&dn, index);
        f2fs_unlock_op(sbi);
-
        if (err) {
                f2fs_put_page(page, 0);
-               return err;
+               goto fail;
        }
 inline_data:
        lock_page(page);
@@ -982,19 +993,20 @@ inline_data:
                        err = f2fs_read_inline_data(inode, page);
                        if (err) {
                                page_cache_release(page);
-                               return err;
+                               goto fail;
                        }
                } else {
                        err = f2fs_submit_page_bio(sbi, page, dn.data_blkaddr,
                                                        READ_SYNC);
                        if (err)
-                               return err;
+                               goto fail;
                }
 
                lock_page(page);
                if (unlikely(!PageUptodate(page))) {
                        f2fs_put_page(page, 1);
-                       return -EIO;
+                       err = -EIO;
+                       goto fail;
                }
                if (unlikely(page->mapping != mapping)) {
                        f2fs_put_page(page, 1);
@@ -1005,6 +1017,9 @@ out:
        SetPageUptodate(page);
        clear_cold_data(page);
        return 0;
+fail:
+       f2fs_write_failed(mapping, pos + len);
+       return err;
 }
 
 static int f2fs_write_end(struct file *file,
@@ -1049,7 +1064,10 @@ static ssize_t f2fs_direct_IO(int rw, struct kiocb *iocb,
                struct iov_iter *iter, loff_t offset)
 {
        struct file *file = iocb->ki_filp;
-       struct inode *inode = file->f_mapping->host;
+       struct address_space *mapping = file->f_mapping;
+       struct inode *inode = mapping->host;
+       size_t count = iov_iter_count(iter);
+       int err;
 
        /* Let buffer I/O handle the inline data case. */
        if (f2fs_has_inline_data(inode))
@@ -1061,8 +1079,10 @@ static ssize_t f2fs_direct_IO(int rw, struct kiocb *iocb,
        /* clear fsync mark to recover these blocks */
        fsync_mark_clear(F2FS_SB(inode->i_sb), inode->i_ino);
 
-       return blockdev_direct_IO(rw, iocb, inode, iter, offset,
-                                 get_data_block);
+       err = blockdev_direct_IO(rw, iocb, inode, iter, offset, get_data_block);
+       if (err < 0 && (rw & WRITE))
+               f2fs_write_failed(mapping, offset + count);
+       return err;
 }
 
 static void f2fs_invalidate_data_page(struct page *page, unsigned int offset,