ext4: add checks for errors from jbd2

If the journal has aborted due to a checkpointing failure, we
have to keep the contents of the journal space.  Otherwise, the
filesystem will lose uncheckpointed metadata completely and
become inconsistent.  To avoid this, we need to keep needs_recovery
flag if checkpoint has failed.

With this patch, ext4_put_super() detects a checkpointing failure
from the return value of journal_destroy(), then it invokes
ext4_abort() to make the filesystem read only and keep
needs_recovery flag.  Errors from jbd2_journal_flush() are also
handled by this patch in some places.

Signed-off-by: Hidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

1 files changed, 8 insertions, 4 deletions

diff --git a/fs/ext4/ioctl.c b/fs/ext4/ioctl.c
index ea27eaa0cfe..dc99b4776d5 100644
--- a/fs/ext4/ioctl.c
+++ b/fs/ext4/ioctl.c
@@ -192,7 +192,7 @@ setversion_out:
         case EXT4_IOC_GROUP_EXTEND: {
                 ext4_fsblk_t n_blocks_count;
                 struct super_block *sb = inode->i_sb;
-                int err;
+                int err, err2;
 
                 if (!capable(CAP_SYS_RESOURCE))
                         return -EPERM;
@@ -206,8 +206,10 @@ setversion_out:
 
                 err = ext4_group_extend(sb, EXT4_SB(sb)->s_es, n_blocks_count);
                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
-                jbd2_journal_flush(EXT4_SB(sb)->s_journal);
+                err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
+                if (err == 0)
+                        err = err2;
                 mnt_drop_write(filp->f_path.mnt);
 
                 return err;
@@ -215,7 +217,7 @@ setversion_out:
         case EXT4_IOC_GROUP_ADD: {
                 struct ext4_new_group_data input;
                 struct super_block *sb = inode->i_sb;
-                int err;
+                int err, err2;
 
                 if (!capable(CAP_SYS_RESOURCE))
                         return -EPERM;
@@ -230,8 +232,10 @@ setversion_out:
 
                 err = ext4_group_add(sb, &input);
                 jbd2_journal_lock_updates(EXT4_SB(sb)->s_journal);
-                jbd2_journal_flush(EXT4_SB(sb)->s_journal);
+                err2 = jbd2_journal_flush(EXT4_SB(sb)->s_journal);
                 jbd2_journal_unlock_updates(EXT4_SB(sb)->s_journal);
+                if (err == 0)
+                        err = err2;
                 mnt_drop_write(filp->f_path.mnt);
 
                 return err;