ext4: add i_data_sem sanity check

Each caller of ext4_ext_dirty must hold i_data_sem,
The only exception is migration code, let's make it convenient.

Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Reviewed-by: Jan Kara <jack@suse.cz>
This commit is contained in:
Dmitry Monakhov 2014-07-27 22:28:15 -04:00 committed by Theodore Ts'o
parent b27b1535ac
commit 4b1f166071
2 changed files with 9 additions and 0 deletions

View File

@ -161,6 +161,8 @@ int __ext4_ext_dirty(const char *where, unsigned int line, handle_t *handle,
struct inode *inode, struct ext4_ext_path *path)
{
int err;
WARN_ON(!rwsem_is_locked(&EXT4_I(inode)->i_data_sem));
if (path->p_bh) {
ext4_extent_block_csum_set(inode, ext_block_hdr(path->p_bh));
/* path points to block */

View File

@ -39,6 +39,8 @@ static int finish_range(handle_t *handle, struct inode *inode,
newext.ee_block = cpu_to_le32(lb->first_block);
newext.ee_len = cpu_to_le16(lb->last_block - lb->first_block + 1);
ext4_ext_store_pblock(&newext, lb->first_pblock);
/* Locking only for convinience since we are operating on temp inode */
down_write(&EXT4_I(inode)->i_data_sem);
path = ext4_ext_find_extent(inode, lb->first_block, NULL, 0);
if (IS_ERR(path)) {
@ -61,7 +63,9 @@ static int finish_range(handle_t *handle, struct inode *inode,
*/
if (needed && ext4_handle_has_enough_credits(handle,
EXT4_RESERVE_TRANS_BLOCKS)) {
up_write((&EXT4_I(inode)->i_data_sem));
retval = ext4_journal_restart(handle, needed);
down_write((&EXT4_I(inode)->i_data_sem));
if (retval)
goto err_out;
} else if (needed) {
@ -70,13 +74,16 @@ static int finish_range(handle_t *handle, struct inode *inode,
/*
* IF not able to extend the journal restart the journal
*/
up_write((&EXT4_I(inode)->i_data_sem));
retval = ext4_journal_restart(handle, needed);
down_write((&EXT4_I(inode)->i_data_sem));
if (retval)
goto err_out;
}
}
retval = ext4_ext_insert_extent(handle, inode, path, &newext, 0);
err_out:
up_write((&EXT4_I(inode)->i_data_sem));
if (path) {
ext4_ext_drop_refs(path);
kfree(path);