linux/fs/ext4/ext4_jbd2.c
Curt Wohlgemuth e6b5d30104 ext4: Fix buffer head reference leak in no-journal mode
We found a problem with buffer head reference leaks when using an ext4
partition without a journal.  In particular, calls to ext4_forget() would
not to a brelse() on the input buffer head, which will cause pages they
belong to to not be reclaimable.

Further investigation showed that all places where ext4_journal_forget() and
ext4_journal_revoke() are called are subject to the same problem.  The patch
below changes __ext4_journal_forget/__ext4_journal_revoke to do an explicit
release of the buffer head when the journal handle isn't valid.

Signed-off-by: Curt Wohlgemuth <curtw@google.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
2009-07-13 09:07:20 -04:00

106 lines
2.2 KiB
C

/*
* Interface between ext4 and JBD
*/
#include "ext4_jbd2.h"
int __ext4_journal_get_undo_access(const char *where, handle_t *handle,
struct buffer_head *bh)
{
int err = 0;
if (ext4_handle_valid(handle)) {
err = jbd2_journal_get_undo_access(handle, bh);
if (err)
ext4_journal_abort_handle(where, __func__, bh,
handle, err);
}
return err;
}
int __ext4_journal_get_write_access(const char *where, handle_t *handle,
struct buffer_head *bh)
{
int err = 0;
if (ext4_handle_valid(handle)) {
err = jbd2_journal_get_write_access(handle, bh);
if (err)
ext4_journal_abort_handle(where, __func__, bh,
handle, err);
}
return err;
}
int __ext4_journal_forget(const char *where, handle_t *handle,
struct buffer_head *bh)
{
int err = 0;
if (ext4_handle_valid(handle)) {
err = jbd2_journal_forget(handle, bh);
if (err)
ext4_journal_abort_handle(where, __func__, bh,
handle, err);
}
else
brelse(bh);
return err;
}
int __ext4_journal_revoke(const char *where, handle_t *handle,
ext4_fsblk_t blocknr, struct buffer_head *bh)
{
int err = 0;
if (ext4_handle_valid(handle)) {
err = jbd2_journal_revoke(handle, blocknr, bh);
if (err)
ext4_journal_abort_handle(where, __func__, bh,
handle, err);
}
else
brelse(bh);
return err;
}
int __ext4_journal_get_create_access(const char *where,
handle_t *handle, struct buffer_head *bh)
{
int err = 0;
if (ext4_handle_valid(handle)) {
err = jbd2_journal_get_create_access(handle, bh);
if (err)
ext4_journal_abort_handle(where, __func__, bh,
handle, err);
}
return err;
}
int __ext4_handle_dirty_metadata(const char *where, handle_t *handle,
struct inode *inode, struct buffer_head *bh)
{
int err = 0;
if (ext4_handle_valid(handle)) {
err = jbd2_journal_dirty_metadata(handle, bh);
if (err)
ext4_journal_abort_handle(where, __func__, bh,
handle, err);
} else {
mark_buffer_dirty(bh);
if (inode && inode_needs_sync(inode)) {
sync_dirty_buffer(bh);
if (buffer_req(bh) && !buffer_uptodate(bh)) {
ext4_error(inode->i_sb, __func__,
"IO error syncing inode, "
"inode=%lu, block=%llu",
inode->i_ino,
(unsigned long long) bh->b_blocknr);
err = -EIO;
}
}
}
return err;
}