Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 6ae09575 authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Jan Kara
Browse files

quota: special case Q_SYNC without device name 



The Q_SYNC command can be called without the path to a device, in which case
it iterates over all superblocks.  Special case this variant directly in
sys_quotactl so that the other code always gets a superblock and doesn't
need to deal with this case.

Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Signed-off-by: default avatarJan Kara <jack@suse.cz>
parent f450d4fe

fs/quota/quota.c

+27 −13
Original line number Diff line number Diff line
@@ -124,10 +124,17 @@ void sync_quota_sb(struct super_block *sb, int type) 
}

#endif



static void sync_dquots(int type)

static int quota_sync_all(int type)

{

	struct super_block *sb;

	int cnt;

	int ret;



	if (type >= MAXQUOTAS)

		return -EINVAL;

	ret = security_quotactl(Q_SYNC, type, 0, NULL);

	if (ret)

		return ret;



	spin_lock(&sb_lock);

restart:
@@ -157,6 +164,8 @@ static void sync_dquots(int type) 
			goto restart;

	}

	spin_unlock(&sb_lock);



	return 0;

}



static int quota_quotaon(struct super_block *sb, int type, int cmd, qid_t id,
@@ -322,12 +331,9 @@ static int do_quotactl(struct super_block *sb, int type, int cmd, qid_t id, 
	case Q_SETQUOTA:

		return quota_setquota(sb, type, id, addr);

	case Q_SYNC:

		if (sb) {

		if (!sb->s_qcop->quota_sync)

			return -ENOSYS;

		sync_quota_sb(sb, type);

		} else

			sync_dquots(type);

		return 0;

	case Q_XQUOTAON:

	case Q_XQUOTAOFF:
@@ -392,18 +398,26 @@ SYSCALL_DEFINE4(quotactl, unsigned int, cmd, const char __user *, special, 
	cmds = cmd >> SUBCMDSHIFT;

	type = cmd & SUBCMDMASK;



	if (cmds != Q_SYNC || special) {

	/*

	 * As a special case Q_SYNC can be called without a specific device.

	 * It will iterate all superblocks that have quota enabled and call

	 * the sync action on each of them.

	 */

	if (!special) {

		if (cmds == Q_SYNC)

			return quota_sync_all(type);

		return -ENODEV;

	}



	sb = quotactl_block(special);

	if (IS_ERR(sb))

		return PTR_ERR(sb);

	}



	ret = check_quotactl_valid(sb, type, cmds, id);

	if (ret >= 0)

		ret = do_quotactl(sb, type, cmds, id, addr);

	if (sb)

		drop_super(sb);



	drop_super(sb);

	return ret;

}