quota: Wire up ->quota_{enable,disable} callbacks into Q_QUOTA{ON,OFF}

Make Q_QUOTAON / Q_QUOTAOFF quotactl call ->quota_enable /
->quota_disable callback when provided. To match current behavior of
ocfs2 & ext4 we make these quotactls turn on / off quota enforcement for
appropriate quota type.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jan Kara <jack@suse.cz>

1 files changed, 27 insertions, 4 deletions

diff --git a/fs/quota/quota.c b/fs/quota/quota.c
index e2ae2b99e555..ce78a70a596f 100644
--- a/fs/quota/quota.c
+++ b/fs/quota/quota.c
@@ -66,18 +66,43 @@ static int quota_sync_all(int type)
         return ret;
 }
 
+unsigned int qtype_enforce_flag(int type)
+{
+        switch (type) {
+        case USRQUOTA:
+                return FS_QUOTA_UDQ_ENFD;
+        case GRPQUOTA:
+                return FS_QUOTA_GDQ_ENFD;
+        case PRJQUOTA:
+                return FS_QUOTA_PDQ_ENFD;
+        }
+        return 0;
+}
+
 static int quota_quotaon(struct super_block *sb, int type, int cmd, qid_t id,
                          struct path *path)
 {
-        if (!sb->s_qcop->quota_on && !sb->s_qcop->quota_on_meta)
+        if (!sb->s_qcop->quota_on && !sb->s_qcop->quota_on_meta &&
+            !sb->s_qcop->quota_enable)
                 return -ENOSYS;
         if (sb->s_qcop->quota_on_meta)
                 return sb->s_qcop->quota_on_meta(sb, type, id);
+        if (sb->s_qcop->quota_enable)
+                return sb->s_qcop->quota_enable(sb, qtype_enforce_flag(type));
         if (IS_ERR(path))
                 return PTR_ERR(path);
         return sb->s_qcop->quota_on(sb, type, id, path);
 }
 
+static int quota_quotaoff(struct super_block *sb, int type)
+{
+        if (!sb->s_qcop->quota_off && !sb->s_qcop->quota_disable)
+                return -ENOSYS;
+        if (sb->s_qcop->quota_disable)
+                return sb->s_qcop->quota_disable(sb, qtype_enforce_flag(type));
+        return sb->s_qcop->quota_off(sb, type);
+}
+
 static int quota_getfmt(struct super_block *sb, int type, void __user *addr)
 {
         __u32 fmt;
@@ -440,9 +465,7 @@ static int do_quotactl(struct super_block *sb, int type, int cmd, qid_t id,
         case Q_QUOTAON:
                 return quota_quotaon(sb, type, cmd, id, path);
         case Q_QUOTAOFF:
-                if (!sb->s_qcop->quota_off)
-                        return -ENOSYS;
-                return sb->s_qcop->quota_off(sb, type);
+                return quota_quotaoff(sb, type);
         case Q_GETFMT:
                 return quota_getfmt(sb, type, addr);
         case Q_GETINFO: