GFS2: quota allows exceeding hard limit

Immediately after being synced to disk, cached quotas are zeroed out and a
subsequent access of the cached quotas results in incorrect zero values. This
meant that gfs2 assumed the actual usage to be the zero (or near-zero) usage
values it found in the cached quotas and comparison against warn/limits never
triggered a quota violation.

This patch adds a new flag QDF_REFRESH that is set after a sync so that the
cached quotas are forcefully refreshed from disk on a subsequent access on
seeing this flag set.

Resolves: rhbz#675944
Signed-off-by: Abhi Das <adas@redhat.com>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
This commit is contained in:
Abhijith Das 2011-03-08 10:40:42 -05:00 committed by Steven Whitehouse
parent 4c16c36ad6
commit 662e3a551b
2 changed files with 8 additions and 1 deletions

View File

@ -317,6 +317,7 @@ enum {
QDF_USER = 0,
QDF_CHANGE = 1,
QDF_LOCKED = 2,
QDF_REFRESH = 3,
};
struct gfs2_quota_data {

View File

@ -834,6 +834,7 @@ static int do_sync(unsigned int num_qd, struct gfs2_quota_data **qda)
goto out_end_trans;
do_qc(qd, -qd->qd_change_sync);
set_bit(QDF_REFRESH, &qd->qd_flags);
}
error = 0;
@ -929,6 +930,7 @@ int gfs2_quota_lock(struct gfs2_inode *ip, u32 uid, u32 gid)
{
struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode);
struct gfs2_alloc *al = ip->i_alloc;
struct gfs2_quota_data *qd;
unsigned int x;
int error = 0;
@ -942,7 +944,11 @@ int gfs2_quota_lock(struct gfs2_inode *ip, u32 uid, u32 gid)
sort_qd, NULL);
for (x = 0; x < al->al_qd_num; x++) {
error = do_glock(al->al_qd[x], NO_FORCE, &al->al_qd_ghs[x]);
int force = NO_FORCE;
qd = al->al_qd[x];
if (test_and_clear_bit(QDF_REFRESH, &qd->qd_flags))
force = FORCE;
error = do_glock(qd, force, &al->al_qd_ghs[x]);
if (error)
break;
}