ceph: quota: support for ceph.quota.max_files

This patch adds support for the max_files quota.  It hooks into all the
ceph functions that add new filesystem objects that need to be checked
against the quota limits.  When these limits are hit, -EDQUOT is returned.

Note that we're not checking quotas on ceph_link().  ceph_link doesn't
really create a new inode,  and since the MDS doesn't update the directory
statistics when a new (hard) link is created (only with symlinks), they
are not accounted as a new file.

Signed-off-by: Luis Henriques <lhenriques@suse.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>

1 files changed, 3 insertions, 1 deletions

diff --git a/fs/ceph/file.c b/fs/ceph/file.c
index 4a92acba1e9c..c3042330e0e9 100644
--- a/fs/ceph/file.c
+++ b/fs/ceph/file.c
@@ -402,7 +402,7 @@ int ceph_atomic_open(struct inode *dir, struct dentry *dentry,
         struct ceph_mds_request *req;
         struct dentry *dn;
         struct ceph_acls_info acls = {};
-       int mask;
+        int mask;
         int err;
 
         dout("atomic_open %p dentry %p '%pd' %s flags %d mode 0%o\n",
@@ -413,6 +413,8 @@ int ceph_atomic_open(struct inode *dir, struct dentry *dentry,
                 return -ENAMETOOLONG;
 
         if (flags & O_CREAT) {
+                if (ceph_quota_is_max_files_exceeded(dir))
+                        return -EDQUOT;
                 err = ceph_pre_init_acls(dir, &mode, &acls);
                 if (err < 0)
                         return err;