quota: Wire up Q_GETXSTATE and Q_GETXSTATV calls to work with ->get_state

Add appropriate conversion functions so that filesystems supporting
->get_state() method can be queried using Q_GETXSTATE and Q_GETXSTATV
calls.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>

fs/quota/quota.c

@@ -269,25 +269,152 @@ static int quota_disable(struct super_block *sb, void __user *addr)
 	return sb->s_qcop->quota_disable(sb, flags);
 }
 
+static int quota_state_to_flags(struct qc_state *state)
+{
+	int flags = 0;
+
+	if (state->s_state[USRQUOTA].flags & QCI_ACCT_ENABLED)
+		flags |= FS_QUOTA_UDQ_ACCT;
+	if (state->s_state[USRQUOTA].flags & QCI_LIMITS_ENFORCED)
+		flags |= FS_QUOTA_UDQ_ENFD;
+	if (state->s_state[GRPQUOTA].flags & QCI_ACCT_ENABLED)
+		flags |= FS_QUOTA_GDQ_ACCT;
+	if (state->s_state[GRPQUOTA].flags & QCI_LIMITS_ENFORCED)
+		flags |= FS_QUOTA_GDQ_ENFD;
+	if (state->s_state[PRJQUOTA].flags & QCI_ACCT_ENABLED)
+		flags |= FS_QUOTA_PDQ_ACCT;
+	if (state->s_state[PRJQUOTA].flags & QCI_LIMITS_ENFORCED)
+		flags |= FS_QUOTA_PDQ_ENFD;
+	return flags;
+}
+
+static int quota_getstate(struct super_block *sb, struct fs_quota_stat *fqs)
+{
+	int type;
+	struct qc_state state;
+	int ret;
+
+	ret = sb->s_qcop->get_state(sb, &state);
+	if (ret < 0)
+		return ret;
+
+	memset(fqs, 0, sizeof(*fqs));
+	fqs->qs_version = FS_QSTAT_VERSION;
+	fqs->qs_flags = quota_state_to_flags(&state);
+	/* No quota enabled? */
+	if (!fqs->qs_flags)
+		return -ENOSYS;
+	fqs->qs_incoredqs = state.s_incoredqs;
+	/*
+	 * GETXSTATE quotactl has space for just one set of time limits so
+	 * report them for the first enabled quota type
+	 */
+	for (type = 0; type < XQM_MAXQUOTAS; type++)
+		if (state.s_state[type].flags & QCI_ACCT_ENABLED)
+			break;
+	BUG_ON(type == XQM_MAXQUOTAS);
+	fqs->qs_btimelimit = state.s_state[type].spc_timelimit;
+	fqs->qs_itimelimit = state.s_state[type].ino_timelimit;
+	fqs->qs_rtbtimelimit = state.s_state[type].rt_spc_timelimit;
+	fqs->qs_bwarnlimit = state.s_state[type].spc_warnlimit;
+	fqs->qs_iwarnlimit = state.s_state[type].ino_warnlimit;
+	if (state.s_state[USRQUOTA].flags & QCI_ACCT_ENABLED) {
+		fqs->qs_uquota.qfs_ino = state.s_state[USRQUOTA].ino;
+		fqs->qs_uquota.qfs_nblks = state.s_state[USRQUOTA].blocks;
+		fqs->qs_uquota.qfs_nextents = state.s_state[USRQUOTA].nextents;
+	}
+	if (state.s_state[GRPQUOTA].flags & QCI_ACCT_ENABLED) {
+		fqs->qs_gquota.qfs_ino = state.s_state[GRPQUOTA].ino;
+		fqs->qs_gquota.qfs_nblks = state.s_state[GRPQUOTA].blocks;
+		fqs->qs_gquota.qfs_nextents = state.s_state[GRPQUOTA].nextents;
+	}
+	if (state.s_state[PRJQUOTA].flags & QCI_ACCT_ENABLED) {
+		/*
+		 * Q_XGETQSTAT doesn't have room for both group and project
+		 * quotas.  So, allow the project quota values to be copied out
+		 * only if there is no group quota information available.
+		 */
+		if (!(state.s_state[GRPQUOTA].flags & QCI_ACCT_ENABLED)) {
+			fqs->qs_gquota.qfs_ino = state.s_state[PRJQUOTA].ino;
+			fqs->qs_gquota.qfs_nblks =
+					state.s_state[PRJQUOTA].blocks;
+			fqs->qs_gquota.qfs_nextents =
+					state.s_state[PRJQUOTA].nextents;
+		}
+	}
+	return 0;
+}
+
 static int quota_getxstate(struct super_block *sb, void __user *addr)
 {
 	struct fs_quota_stat fqs;
 	int ret;
 
-	if (!sb->s_qcop->get_xstate)
+	if (!sb->s_qcop->get_xstate && !sb->s_qcop->get_state)
 		return -ENOSYS;
+	if (sb->s_qcop->get_state)
+		ret = quota_getstate(sb, &fqs);
+	else
 		ret = sb->s_qcop->get_xstate(sb, &fqs);
 	if (!ret && copy_to_user(addr, &fqs, sizeof(fqs)))
 		return -EFAULT;
 	return ret;
 }
 
+static int quota_getstatev(struct super_block *sb, struct fs_quota_statv *fqs)
+{
+	int type;
+	struct qc_state state;
+	int ret;
+
+	ret = sb->s_qcop->get_state(sb, &state);
+	if (ret < 0)
+		return ret;
+
+	memset(fqs, 0, sizeof(*fqs));
+	fqs->qs_version = FS_QSTAT_VERSION;
+	fqs->qs_flags = quota_state_to_flags(&state);
+	/* No quota enabled? */
+	if (!fqs->qs_flags)
+		return -ENOSYS;
+	fqs->qs_incoredqs = state.s_incoredqs;
+	/*
+	 * GETXSTATV quotactl has space for just one set of time limits so
+	 * report them for the first enabled quota type
+	 */
+	for (type = 0; type < XQM_MAXQUOTAS; type++)
+		if (state.s_state[type].flags & QCI_ACCT_ENABLED)
+			break;
+	BUG_ON(type == XQM_MAXQUOTAS);
+	fqs->qs_btimelimit = state.s_state[type].spc_timelimit;
+	fqs->qs_itimelimit = state.s_state[type].ino_timelimit;
+	fqs->qs_rtbtimelimit = state.s_state[type].rt_spc_timelimit;
+	fqs->qs_bwarnlimit = state.s_state[type].spc_warnlimit;
+	fqs->qs_iwarnlimit = state.s_state[type].ino_warnlimit;
+	if (state.s_state[USRQUOTA].flags & QCI_ACCT_ENABLED) {
+		fqs->qs_uquota.qfs_ino = state.s_state[USRQUOTA].ino;
+		fqs->qs_uquota.qfs_nblks = state.s_state[USRQUOTA].blocks;
+		fqs->qs_uquota.qfs_nextents = state.s_state[USRQUOTA].nextents;
+	}
+	if (state.s_state[GRPQUOTA].flags & QCI_ACCT_ENABLED) {
+		fqs->qs_gquota.qfs_ino = state.s_state[GRPQUOTA].ino;
+		fqs->qs_gquota.qfs_nblks = state.s_state[GRPQUOTA].blocks;
+		fqs->qs_gquota.qfs_nextents = state.s_state[GRPQUOTA].nextents;
+	}
+	if (state.s_state[PRJQUOTA].flags & QCI_ACCT_ENABLED) {
+		fqs->qs_pquota.qfs_ino = state.s_state[PRJQUOTA].ino;
+		fqs->qs_pquota.qfs_nblks = state.s_state[PRJQUOTA].blocks;
+		fqs->qs_pquota.qfs_nextents = state.s_state[PRJQUOTA].nextents;
+	}
+	return 0;
+}
+
 static int quota_getxstatev(struct super_block *sb, void __user *addr)
 {
 	struct fs_quota_statv fqs;
 	int ret;
 
-	if (!sb->s_qcop->get_xstatev)
+	if (!sb->s_qcop->get_xstatev && !sb->s_qcop->get_state)
 		return -ENOSYS;
 
 	memset(&fqs, 0, sizeof(fqs));
@@ -301,6 +428,9 @@ static int quota_getxstatev(struct super_block *sb, void __user *addr)
 	default:
 		return -EINVAL;
 	}
+	if (sb->s_qcop->get_state)
+		ret = quota_getstatev(sb, &fqs);
+	else
 		ret = sb->s_qcop->get_xstatev(sb, &fqs);
 	if (!ret && copy_to_user(addr, &fqs, sizeof(fqs)))
 		return -EFAULT;