Offering: HULK
hulk inclusion
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I9DN5Z
--------------------------------
Since commit 7f6416dcd4a3f ("ext4: implement writeback iomap path"), the
order mode is removed in iomap framework, which lets ext4_mb_clear_bb()
free data blocks immediately. It may cause stale data read from truncated
file in power-cut case. Following is details:
P1 P2
vfs_truncate(file A)
ext4_setattr
EXT4_I(inode)->i_disksize = attr->ia_size // record in journal
ext4_truncate
ext4_mb_clear_bb
mb_free_blocks // free block i
vfs_write(file B) // get block i and writeback
>> powercut <<
In the next mount, inode size and extent tree is stale(before truncated),
the content in block i is file B.
Fix the problem by tracking free data blocks in journal for
iomap/non-writeback case.
Fixes: 7f6416dcd4a3 ("ext4: implement writeback iomap path")
Signed-off-by: Zhihao Cheng <chengzhihao1(a)huawei.com>
---
fs/ext4/ext4_jbd2.c | 9 ++-------
fs/ext4/ext4_jbd2.h | 7 +++++++
2 files changed, 9 insertions(+), 7 deletions(-)
diff --git a/fs/ext4/ext4_jbd2.c b/fs/ext4/ext4_jbd2.c
index 94c8073b49e7..cac0eb5068d3 100644
--- a/fs/ext4/ext4_jbd2.c
+++ b/fs/ext4/ext4_jbd2.c
@@ -11,18 +11,13 @@ int ext4_inode_journal_mode(struct inode *inode)
{
if (EXT4_JOURNAL(inode) == NULL)
return EXT4_INODE_WRITEBACK_DATA_MODE; /* writeback */
- /*
- * Ordered mode is no longer needed for the inode that use the
- * iomap path, always use writeback mode.
- */
- if (ext4_test_inode_state(inode, EXT4_STATE_BUFFERED_IOMAP))
- return EXT4_INODE_WRITEBACK_DATA_MODE; /* writeback */
/* We do not support data journalling with delayed allocation */
if (!S_ISREG(inode->i_mode) ||
ext4_test_inode_flag(inode, EXT4_INODE_EA_INODE) ||
test_opt(inode->i_sb, DATA_FLAGS) == EXT4_MOUNT_JOURNAL_DATA ||
(ext4_test_inode_flag(inode, EXT4_INODE_JOURNAL_DATA) &&
- !test_opt(inode->i_sb, DELALLOC))) {
+ !test_opt(inode->i_sb, DELALLOC) &&
+ !ext4_test_inode_state(inode, EXT4_STATE_BUFFERED_IOMAP))) {
/* We do not support data journalling for encrypted data */
if (S_ISREG(inode->i_mode) && IS_ENCRYPTED(inode))
return EXT4_INODE_ORDERED_DATA_MODE; /* ordered */
diff --git a/fs/ext4/ext4_jbd2.h b/fs/ext4/ext4_jbd2.h
index 0c77697d5e90..c52d1caf6622 100644
--- a/fs/ext4/ext4_jbd2.h
+++ b/fs/ext4/ext4_jbd2.h
@@ -467,6 +467,13 @@ static inline int ext4_should_journal_data(struct inode *inode)
static inline int ext4_should_order_data(struct inode *inode)
{
+ /*
+ * Ordered mode is no longer needed for the inode that use the
+ * iomap path, always use writeback mode.
+ */
+ if (ext4_test_inode_state(inode, EXT4_STATE_BUFFERED_IOMAP))
+ return 0; /* writeback */
+
return ext4_inode_journal_mode(inode) & EXT4_INODE_ORDERED_DATA_MODE;
}
--
2.31.1