quota: Allow each filesystem to specify which quota types it supports
Currently all filesystems supporting VFS quota support user and group
quotas. With introduction of project quotas this is going to change so
make sure filesystem isn't called for quota type it doesn't support by
introduction of a bitmask determining which quota types each filesystem
supports.
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>
diff --git a/fs/quota/quota.c b/fs/quota/quota.c
index 7562164..2aa4151 100644
--- a/fs/quota/quota.c
+++ b/fs/quota/quota.c
@@ -47,8 +47,11 @@
static void quota_sync_one(struct super_block *sb, void *arg)
{
- if (sb->s_qcop && sb->s_qcop->quota_sync)
- sb->s_qcop->quota_sync(sb, *(int *)arg);
+ int type = *(int *)arg;
+
+ if (sb->s_qcop && sb->s_qcop->quota_sync &&
+ (sb->s_quota_types & (1 << type)))
+ sb->s_qcop->quota_sync(sb, type);
}
static int quota_sync_all(int type)
@@ -297,8 +300,14 @@
if (type >= (XQM_COMMAND(cmd) ? XQM_MAXQUOTAS : MAXQUOTAS))
return -EINVAL;
+ /*
+ * Quota not supported on this fs? Check this before s_quota_types
+ * since they needn't be set if quota is not supported at all.
+ */
if (!sb->s_qcop)
return -ENOSYS;
+ if (!(sb->s_quota_types & (1 << type)))
+ return -EINVAL;
ret = check_quotactl_permission(sb, type, cmd, id);
if (ret < 0)
diff --git a/fs/super.c b/fs/super.c
index eae088f..4512281 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -218,6 +218,12 @@
atomic_set(&s->s_active, 1);
mutex_init(&s->s_vfs_rename_mutex);
lockdep_set_class(&s->s_vfs_rename_mutex, &type->s_vfs_rename_key);
+ /*
+ * For now MAXQUOTAS check in do_quotactl() will limit quota type
+ * appropriately. When each fs sets allowed_types, we can remove the
+ * line below
+ */
+ s->s_quota_types = QTYPE_MASK_USR | QTYPE_MASK_GRP | QTYPE_MASK_PRJ;
mutex_init(&s->s_dquot.dqio_mutex);
mutex_init(&s->s_dquot.dqonoff_mutex);
s->s_maxbytes = MAX_NON_LFS;
diff --git a/include/linux/fs.h b/include/linux/fs.h
index 9ab779e..cf55a548 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -1224,6 +1224,7 @@
struct backing_dev_info *s_bdi;
struct mtd_info *s_mtd;
struct hlist_node s_instances;
+ unsigned int s_quota_types; /* Bitmask of supported quota types */
struct quota_info s_dquot; /* Diskquota specific options */
struct sb_writers s_writers;
diff --git a/include/linux/quota.h b/include/linux/quota.h
index 80d345a..50978b7 100644
--- a/include/linux/quota.h
+++ b/include/linux/quota.h
@@ -56,6 +56,11 @@
PRJQUOTA = 2, /* element used for project quotas */
};
+/* Masks for quota types when used as a bitmask */
+#define QTYPE_MASK_USR (1 << USRQUOTA)
+#define QTYPE_MASK_GRP (1 << GRPQUOTA)
+#define QTYPE_MASK_PRJ (1 << PRJQUOTA)
+
typedef __kernel_uid32_t qid_t; /* Type in which we store ids in memory */
typedef long long qsize_t; /* Type in which we store sizes */
