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>
diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c
index 16405e0..7d9851c 100644
--- a/fs/ceph/dir.c
+++ b/fs/ceph/dir.c
@@ -828,6 +828,9 @@ static int ceph_mknod(struct inode *dir, struct dentry *dentry,
if (ceph_snap(dir) != CEPH_NOSNAP)
return -EROFS;
+ if (ceph_quota_is_max_files_exceeded(dir))
+ return -EDQUOT;
+
err = ceph_pre_init_acls(dir, &mode, &acls);
if (err < 0)
return err;
@@ -881,6 +884,9 @@ static int ceph_symlink(struct inode *dir, struct dentry *dentry,
if (ceph_snap(dir) != CEPH_NOSNAP)
return -EROFS;
+ if (ceph_quota_is_max_files_exceeded(dir))
+ return -EDQUOT;
+
dout("symlink in dir %p dentry %p to '%s'\n", dir, dentry, dest);
req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_SYMLINK, USE_AUTH_MDS);
if (IS_ERR(req)) {
@@ -930,6 +936,11 @@ static int ceph_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode)
goto out;
}
+ if (ceph_quota_is_max_files_exceeded(dir)) {
+ err = -EDQUOT;
+ goto out;
+ }
+
mode |= S_IFDIR;
err = ceph_pre_init_acls(dir, &mode, &acls);
if (err < 0)
diff --git a/fs/ceph/file.c b/fs/ceph/file.c
index 4a92acb..c304233 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;
diff --git a/fs/ceph/quota.c b/fs/ceph/quota.c
index 1b69d83..cf1c78c 100644
--- a/fs/ceph/quota.c
+++ b/fs/ceph/quota.c
@@ -63,3 +63,83 @@ void ceph_handle_quota(struct ceph_mds_client *mdsc,
iput(inode);
}
+
+enum quota_check_op {
+ QUOTA_CHECK_MAX_FILES_OP /* check quota max_files limit */
+};
+
+/*
+ * check_quota_exceeded() will walk up the snaprealm hierarchy and, for each
+ * realm, it will execute quota check operation defined by the 'op' parameter.
+ * The snaprealm walk is interrupted if the quota check detects that the quota
+ * is exceeded or if the root inode is reached.
+ */
+static bool check_quota_exceeded(struct inode *inode, enum quota_check_op op,
+ loff_t delta)
+{
+ struct ceph_mds_client *mdsc = ceph_inode_to_client(inode)->mdsc;
+ struct ceph_inode_info *ci;
+ struct ceph_snap_realm *realm, *next;
+ struct ceph_vino vino;
+ struct inode *in;
+ u64 max, rvalue;
+ bool is_root;
+ bool exceeded = false;
+
+ down_read(&mdsc->snap_rwsem);
+ realm = ceph_inode(inode)->i_snap_realm;
+ ceph_get_snap_realm(mdsc, realm);
+ while (realm) {
+ vino.ino = realm->ino;
+ vino.snap = CEPH_NOSNAP;
+ in = ceph_find_inode(inode->i_sb, vino);
+ if (!in) {
+ pr_warn("Failed to find inode for %llu\n", vino.ino);
+ break;
+ }
+ ci = ceph_inode(in);
+ spin_lock(&ci->i_ceph_lock);
+ if (op == QUOTA_CHECK_MAX_FILES_OP) {
+ max = ci->i_max_files;
+ rvalue = ci->i_rfiles + ci->i_rsubdirs;
+ }
+ is_root = (ci->i_vino.ino == CEPH_INO_ROOT);
+ spin_unlock(&ci->i_ceph_lock);
+ switch (op) {
+ case QUOTA_CHECK_MAX_FILES_OP:
+ exceeded = (max && (rvalue >= max));
+ break;
+ default:
+ /* Shouldn't happen */
+ pr_warn("Invalid quota check op (%d)\n", op);
+ exceeded = true; /* Just break the loop */
+ }
+ iput(in);
+
+ if (is_root || exceeded)
+ break;
+ next = realm->parent;
+ ceph_get_snap_realm(mdsc, next);
+ ceph_put_snap_realm(mdsc, realm);
+ realm = next;
+ }
+ ceph_put_snap_realm(mdsc, realm);
+ up_read(&mdsc->snap_rwsem);
+
+ return exceeded;
+}
+
+/*
+ * ceph_quota_is_max_files_exceeded - check if we can create a new file
+ * @inode: directory where a new file is being created
+ *
+ * This functions returns true is max_files quota allows a new file to be
+ * created. It is necessary to walk through the snaprealm hierarchy (until the
+ * FS root) to check all realms with quotas set.
+ */
+bool ceph_quota_is_max_files_exceeded(struct inode *inode)
+{
+ WARN_ON(!S_ISDIR(inode->i_mode));
+
+ return check_quota_exceeded(inode, QUOTA_CHECK_MAX_FILES_OP, 0);
+}
diff --git a/fs/ceph/super.h b/fs/ceph/super.h
index 0c95a92..4afc6cc 100644
--- a/fs/ceph/super.h
+++ b/fs/ceph/super.h
@@ -1077,5 +1077,6 @@ extern void ceph_fs_debugfs_cleanup(struct ceph_fs_client *client);
extern void ceph_handle_quota(struct ceph_mds_client *mdsc,
struct ceph_mds_session *session,
struct ceph_msg *msg);
+extern bool ceph_quota_is_max_files_exceeded(struct inode *inode);
#endif /* _FS_CEPH_SUPER_H */