ext4: Handle unwritten extent properly with delayed allocation
When using fallocate the buffer_heads are marked unwritten and unmapped.
We need to map them in the writepages after a get_block. Otherwise we
split the uninit extents, but never write the content to disk.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Mingming Cao <cmm@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 59fbbe8..a1c7d76 100644
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -1741,6 +1741,13 @@
if (buffer_delay(bh)) {
bh->b_blocknr = pblock;
clear_buffer_delay(bh);
+ bh->b_bdev = inode->i_sb->s_bdev;
+ } else if (buffer_unwritten(bh)) {
+ bh->b_blocknr = pblock;
+ clear_buffer_unwritten(bh);
+ set_buffer_mapped(bh);
+ set_buffer_new(bh);
+ bh->b_bdev = inode->i_sb->s_bdev;
} else if (buffer_mapped(bh))
BUG_ON(bh->b_blocknr != pblock);
@@ -1814,7 +1821,7 @@
* If blocks are delayed marked, we need to
* put actual blocknr and drop delayed bit
*/
- if (buffer_delay(lbh))
+ if (buffer_delay(lbh) || buffer_unwritten(lbh))
mpage_put_bnr_to_bhs(mpd, next, &new);
/* go for the remaining blocks */
@@ -1823,7 +1830,8 @@
}
}
-#define BH_FLAGS ((1 << BH_Uptodate) | (1 << BH_Mapped) | (1 << BH_Delay))
+#define BH_FLAGS ((1 << BH_Uptodate) | (1 << BH_Mapped) | \
+ (1 << BH_Delay) | (1 << BH_Unwritten))
/*
* mpage_add_bh_to_extent - try to add one more block to extent of blocks