/* Now when everything is written we can discard the pagecache so
* that userspace sees the changes. We need i_mutex and so we could
- * not do it inside dqonoff_sem. Moreover we need to be carefull
+ * not do it inside dqonoff_mutex. Moreover we need to be carefull
* about races with quotaoff() (that is the reason why we have own
* reference to inode). */
- down(&sb_dqopt(sb)->dqonoff_sem);
+ mutex_lock(&sb_dqopt(sb)->dqonoff_mutex);
for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
discard[cnt] = NULL;
if (type != -1 && cnt != type)
continue;
discard[cnt] = igrab(sb_dqopt(sb)->files[cnt]);
}
- up(&sb_dqopt(sb)->dqonoff_sem);
+ mutex_unlock(&sb_dqopt(sb)->dqonoff_mutex);
for (cnt = 0; cnt < MAXQUOTAS; cnt++) {
if (discard[cnt]) {
mutex_lock(&discard[cnt]->i_mutex);
return 0;
}
+/*
+ * look up a superblock on which quota ops will be performed
+ * - use the name of a block device to find the superblock thereon
+ */
+static inline struct super_block *quotactl_block(const char __user *special)
+{
+#ifdef CONFIG_BLOCK
+ struct block_device *bdev;
+ struct super_block *sb;
+ char *tmp = getname(special);
+
+ if (IS_ERR(tmp))
+ return ERR_PTR(PTR_ERR(tmp));
+ bdev = lookup_bdev(tmp);
+ putname(tmp);
+ if (IS_ERR(bdev))
+ return ERR_PTR(PTR_ERR(bdev));
+ sb = get_super(bdev);
+ bdput(bdev);
+ if (!sb)
+ return ERR_PTR(-ENODEV);
+
+ return sb;
+#else
+ return ERR_PTR(-ENODEV);
+#endif
+}
+
/*
* This is the system call interface. This communicates with
* the user-level programs. Currently this only supports diskquota
{
uint cmds, type;
struct super_block *sb = NULL;
- struct block_device *bdev;
- char *tmp;
int ret;
cmds = cmd >> SUBCMDSHIFT;
type = cmd & SUBCMDMASK;
if (cmds != Q_SYNC || special) {
- tmp = getname(special);
- if (IS_ERR(tmp))
- return PTR_ERR(tmp);
- bdev = lookup_bdev(tmp);
- putname(tmp);
- if (IS_ERR(bdev))
- return PTR_ERR(bdev);
- sb = get_super(bdev);
- bdput(bdev);
- if (!sb)
- return -ENODEV;
+ sb = quotactl_block(special);
+ if (IS_ERR(sb))
+ return PTR_ERR(sb);
}
ret = check_quotactl_valid(sb, type, cmds, id);