| Message ID | 53854153.40601@gmail.com |
|---|---|
| State | Not Applicable, archived |
| Headers | show |
On Wed 28-05-14 09:52:19, Niu Yawei wrote: > Remove dqptr_sem to make quota code scalable: Protect the > Q_GETFMT by dqonoff_mutex instead of dqptr_sem. I'd make the changelog more verbose. Otherwise the patch looks good to me. Something like: dqptr_sem will go away. Protect Q_GETFMT quotactl by dqonoff_mutex instead. This is also enough to make sure quota info will not go away while we are looking at it. Honza > > Signed-off-by: Lai Siyao <lai.siyao@intel.com> > Signed-off-by: Niu Yawei <yawei.niu@intel.com> > --- > fs/quota/quota.c | 6 +++--- > 1 files changed, 3 insertions(+), 3 deletions(-) > > diff --git a/fs/quota/quota.c b/fs/quota/quota.c > index 2b363e2..e4851cb 100644 > --- a/fs/quota/quota.c > +++ b/fs/quota/quota.c > @@ -79,13 +79,13 @@ static int quota_getfmt(struct super_block *sb, int type, void __user *addr) > { > __u32 fmt; > > - down_read(&sb_dqopt(sb)->dqptr_sem); > + mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); > if (!sb_has_quota_active(sb, type)) { > - up_read(&sb_dqopt(sb)->dqptr_sem); > + mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); > return -ESRCH; > } > fmt = sb_dqopt(sb)->info[type].dqi_format->qf_fmt_id; > - up_read(&sb_dqopt(sb)->dqptr_sem); > + mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); > if (copy_to_user(addr, &fmt, sizeof(fmt))) > return -EFAULT; > return 0; > -- > 1.7.1 > >
diff --git a/fs/quota/quota.c b/fs/quota/quota.c index 2b363e2..e4851cb 100644 --- a/fs/quota/quota.c +++ b/fs/quota/quota.c @@ -79,13 +79,13 @@ static int quota_getfmt(struct super_block *sb, int type, void __user *addr) { __u32 fmt; - down_read(&sb_dqopt(sb)->dqptr_sem); + mutex_lock(&sb_dqopt(sb)->dqonoff_mutex); if (!sb_has_quota_active(sb, type)) { - up_read(&sb_dqopt(sb)->dqptr_sem); + mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); return -ESRCH; } fmt = sb_dqopt(sb)->info[type].dqi_format->qf_fmt_id; - up_read(&sb_dqopt(sb)->dqptr_sem); + mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex); if (copy_to_user(addr, &fmt, sizeof(fmt))) return -EFAULT; return 0;