diff options
Diffstat (limited to 'fs/ext4/inode.c')
| -rw-r--r-- | fs/ext4/inode.c | 24 |
1 files changed, 22 insertions, 2 deletions
diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c index 76cb3b1ad78..bed574dd4c2 100644 --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -2996,6 +2996,16 @@ static ssize_t ext4_ext_direct_IO(int rw, struct kiocb *iocb, if (rw == WRITE && final_size <= inode->i_size) { int overwrite = 0; + BUG_ON(iocb->private == NULL); + + /* If we do a overwrite dio, i_mutex locking can be released */ + overwrite = *((int *)iocb->private); + + if (overwrite) { + down_read(&EXT4_I(inode)->i_data_sem); + mutex_unlock(&inode->i_mutex); + } + /* * We could direct write to holes and fallocate. * @@ -3021,8 +3031,10 @@ static ssize_t ext4_ext_direct_IO(int rw, struct kiocb *iocb, if (!is_sync_kiocb(iocb)) { ext4_io_end_t *io_end = ext4_init_io_end(inode, GFP_NOFS); - if (!io_end) - return -ENOMEM; + if (!io_end) { + ret = -ENOMEM; + goto retake_lock; + } io_end->flag |= EXT4_IO_END_DIRECT; iocb->private = io_end; /* @@ -3083,6 +3095,14 @@ static ssize_t ext4_ext_direct_IO(int rw, struct kiocb *iocb, ret = err; ext4_clear_inode_state(inode, EXT4_STATE_DIO_UNWRITTEN); } + + retake_lock: + /* take i_mutex locking again if we do a ovewrite dio */ + if (overwrite) { + up_read(&EXT4_I(inode)->i_data_sem); + mutex_lock(&inode->i_mutex); + } + return ret; } |