diff options
| author | Frank Mayhar <fmayhar@google.com> | 2010-05-17 08:00:00 -0400 |
|---|---|---|
| committer | Paul Gortmaker <paul.gortmaker@windriver.com> | 2011-01-06 18:07:38 -0500 |
| commit | f1da3e1315fc3a2d3ded2434a327b913d7a80092 (patch) | |
| tree | 1300514aef34a1a32802120034f1ec6947b4a3cc /fs/ext4 | |
| parent | f510dd7e84ae263ee730a5b5db6100c6c03c087f (diff) | |
ext4: Make fsync sync new parent directories in no-journal mode
commit 14ece1028b3ed53ffec1b1213ffc6acaf79ad77c upstream.
Add a new ext4 state to tell us when a file has been newly created; use
that state in ext4_sync_file in no-journal mode to tell us when we need
to sync the parent directory as well as the inode and data itself. This
fixes a problem in which a panic or power failure may lose the entire
file even when using fsync, since the parent directory entry is lost.
Addresses-Google-Bug: #2480057
Signed-off-by: Frank Mayhar <fmayhar@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Diffstat (limited to 'fs/ext4')
| -rw-r--r-- | fs/ext4/ext4.h | 1 | ||||
| -rw-r--r-- | fs/ext4/fsync.c | 31 | ||||
| -rw-r--r-- | fs/ext4/namei.c | 2 |
3 files changed, 32 insertions, 2 deletions
diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h index 2e31640ceddd..650ef373698c 100644 --- a/fs/ext4/ext4.h +++ b/fs/ext4/ext4.h @@ -1157,6 +1157,7 @@ enum { EXT4_STATE_DA_ALLOC_CLOSE, /* Alloc DA blks on close */ EXT4_STATE_EXT_MIGRATE, /* Inode is migrating */ EXT4_STATE_DIO_UNWRITTEN, /* need convert on dio done*/ + EXT4_STATE_NEWENTRY, /* File just added to dir */ }; #define EXT4_INODE_BIT_FNS(name, field) \ diff --git a/fs/ext4/fsync.c b/fs/ext4/fsync.c index 42bd94a942c9..6f25f9f769ec 100644 --- a/fs/ext4/fsync.c +++ b/fs/ext4/fsync.c @@ -35,6 +35,29 @@ #include <trace/events/ext4.h> /* + * If we're not journaling and this is a just-created file, we have to + * sync our parent directory (if it was freshly created) since + * otherwise it will only be written by writeback, leaving a huge + * window during which a crash may lose the file. This may apply for + * the parent directory's parent as well, and so on recursively, if + * they are also freshly created. + */ +static void ext4_sync_parent(struct inode *inode) +{ + struct dentry *dentry = NULL; + + while (inode && ext4_test_inode_state(inode, EXT4_STATE_NEWENTRY)) { + ext4_clear_inode_state(inode, EXT4_STATE_NEWENTRY); + dentry = list_entry(inode->i_dentry.next, + struct dentry, d_alias); + if (!dentry || !dentry->d_parent || !dentry->d_parent->d_inode) + break; + inode = dentry->d_parent->d_inode; + sync_mapping_buffers(inode->i_mapping); + } +} + +/* * akpm: A new design for ext4_sync_file(). * * This is only called from sys_fsync(), sys_fdatasync() and sys_msync(). @@ -67,8 +90,12 @@ int ext4_sync_file(struct file *file, struct dentry *dentry, int datasync) if (ret < 0) return ret; - if (!journal) - return simple_fsync(file, dentry, datasync); + if (!journal) { + ret = simple_fsync(file, dentry, datasync); + if (!ret && !list_empty(&inode->i_dentry)) + ext4_sync_parent(inode); + return ret; + } /* * data=writeback,ordered: diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c index efab592683b4..2f31631935ba 100644 --- a/fs/ext4/namei.c +++ b/fs/ext4/namei.c @@ -1519,6 +1519,8 @@ static int ext4_add_entry(handle_t *handle, struct dentry *dentry, de->rec_len = ext4_rec_len_to_disk(blocksize, blocksize); retval = add_dirent_to_buf(handle, dentry, inode, de, bh); brelse(bh); + if (retval == 0) + ext4_set_inode_state(inode, EXT4_STATE_NEWENTRY); return retval; } |