Merge tag 'ceph-for-5.13-rc8' of https://github.com/ceph/ceph-client

Pull ceph fixes from Ilya Dryomov:
 "Two regression fixes from the merge window: one in the auth code
  affecting old clusters and one in the filesystem for proper
  propagation of MDS request errors.

  Also included a locking fix for async creates, marked for stable"

* tag 'ceph-for-5.13-rc8' of https://github.com/ceph/ceph-client:
  libceph: set global_id as soon as we get an auth ticket
  libceph: don't pass result into ac->ops->handle_reply()
  ceph: fix error handling in ceph_atomic_open and ceph_lookup
  ceph: must hold snap_rwsem when filling inode for async create

Author: torvalds

fs/ceph/dir.c

@@ -668,14 +668,13 @@ static loff_t ceph_dir_llseek(struct file *file, loff_t offset, int whence)
  * Handle lookups for the hidden .snap directory.
  */
 struct dentry *ceph_handle_snapdir(struct ceph_mds_request *req,
-				   struct dentry *dentry, int err)
+				   struct dentry *dentry)
 {
 	struct ceph_fs_client *fsc = ceph_sb_to_client(dentry->d_sb);
 	struct inode *parent = d_inode(dentry->d_parent); /* we hold i_mutex */
 
 	/* .snap dir? */
-	if (err == -ENOENT &&
-	    ceph_snap(parent) == CEPH_NOSNAP &&
+	if (ceph_snap(parent) == CEPH_NOSNAP &&
 	    strcmp(dentry->d_name.name, fsc->mount_options->snapdir_name) == 0) {
 		struct dentry *res;
 		struct inode *inode = ceph_get_snapdir(parent);
@@ -742,7 +741,6 @@ static struct dentry *ceph_lookup(struct inode *dir, struct dentry *dentry,
 	struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb);
 	struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(dir->i_sb);
 	struct ceph_mds_request *req;
-	struct dentry *res;
 	int op;
 	int mask;
 	int err;
@@ -793,12 +791,16 @@ static struct dentry *ceph_lookup(struct inode *dir, struct dentry *dentry,
 	req->r_parent = dir;
 	set_bit(CEPH_MDS_R_PARENT_LOCKED, &req->r_req_flags);
 	err = ceph_mdsc_do_request(mdsc, NULL, req);
-	res = ceph_handle_snapdir(req, dentry, err);
-	if (IS_ERR(res)) {
-		err = PTR_ERR(res);
-	} else {
-		dentry = res;
-		err = 0;
+	if (err == -ENOENT) {
+		struct dentry *res;
+
+		res = ceph_handle_snapdir(req, dentry);
+		if (IS_ERR(res)) {
+			err = PTR_ERR(res);
+		} else {
+			dentry = res;
+			err = 0;
+		}
 	}
 	dentry = ceph_finish_lookup(req, dentry, err);
 	ceph_mdsc_put_request(req);  /* will dput(dentry) */

fs/ceph/file.c

@@ -578,6 +578,7 @@ static int ceph_finish_async_create(struct inode *dir, struct dentry *dentry,
 	struct ceph_inode_info *ci = ceph_inode(dir);
 	struct inode *inode;
 	struct timespec64 now;
+	struct ceph_mds_client *mdsc = ceph_sb_to_mdsc(dir->i_sb);
 	struct ceph_vino vino = { .ino = req->r_deleg_ino,
 				  .snap = CEPH_NOSNAP };
 
@@ -615,8 +616,10 @@ static int ceph_finish_async_create(struct inode *dir, struct dentry *dentry,
 
 	ceph_file_layout_to_legacy(lo, &in.layout);
 
+	down_read(&mdsc->snap_rwsem);
 	ret = ceph_fill_inode(inode, NULL, &iinfo, NULL, req->r_session,
 			      req->r_fmode, NULL);
+	up_read(&mdsc->snap_rwsem);
 	if (ret) {
 		dout("%s failed to fill inode: %d\n", __func__, ret);
 		ceph_dir_clear_complete(dir);
@@ -739,14 +742,16 @@ int ceph_atomic_open(struct inode *dir, struct dentry *dentry,
 	err = ceph_mdsc_do_request(mdsc,
 				   (flags & (O_CREAT|O_TRUNC)) ? dir : NULL,
 				   req);
-	dentry = ceph_handle_snapdir(req, dentry, err);
-	if (IS_ERR(dentry)) {
-		err = PTR_ERR(dentry);
-		goto out_req;
+	if (err == -ENOENT) {
+		dentry = ceph_handle_snapdir(req, dentry);
+		if (IS_ERR(dentry)) {
+			err = PTR_ERR(dentry);
+			goto out_req;
+		}
+		err = 0;
 	}
-	err = 0;
 
-	if ((flags & O_CREAT) && !req->r_reply_info.head->is_dentry)
+	if (!err && (flags & O_CREAT) && !req->r_reply_info.head->is_dentry)
 		err = ceph_handle_notrace_create(dir, dentry);
 
 	if (d_in_lookup(dentry)) {

fs/ceph/inode.c

@@ -777,6 +777,8 @@ int ceph_fill_inode(struct inode *inode, struct page *locked_page,
 	umode_t mode = le32_to_cpu(info->mode);
 	dev_t rdev = le32_to_cpu(info->rdev);
 
+	lockdep_assert_held(&mdsc->snap_rwsem);
+
 	dout("%s %p ino %llx.%llx v %llu had %llu\n", __func__,
 	     inode, ceph_vinop(inode), le64_to_cpu(info->version),
 	     ci->i_version);

fs/ceph/super.h

@@ -1218,7 +1218,7 @@ extern const struct dentry_operations ceph_dentry_ops;
 extern loff_t ceph_make_fpos(unsigned high, unsigned off, bool hash_order);
 extern int ceph_handle_notrace_create(struct inode *dir, struct dentry *dentry);
 extern struct dentry *ceph_handle_snapdir(struct ceph_mds_request *req,
-			       struct dentry *dentry, int err);
+			       struct dentry *dentry);
 extern struct dentry *ceph_finish_lookup(struct ceph_mds_request *req,
 					 struct dentry *dentry, int err);
 

include/linux/ceph/auth.h

@@ -50,7 +50,7 @@ struct ceph_auth_client_ops {
 	 * another request.
 	 */
 	int (*build_request)(struct ceph_auth_client *ac, void *buf, void *end);
-	int (*handle_reply)(struct ceph_auth_client *ac, int result,
+	int (*handle_reply)(struct ceph_auth_client *ac, u64 global_id,
 			    void *buf, void *end, u8 *session_key,
 			    int *session_key_len, u8 *con_secret,
 			    int *con_secret_len);
@@ -104,6 +104,8 @@ struct ceph_auth_client {
 	struct mutex mutex;
 };
 
+void ceph_auth_set_global_id(struct ceph_auth_client *ac, u64 global_id);
+
 struct ceph_auth_client *ceph_auth_init(const char *name,
 					const struct ceph_crypto_key *key,
 					const int *con_modes);

net/ceph/auth.c

@@ -36,7 +36,7 @@ static int init_protocol(struct ceph_auth_client *ac, int proto)
 	}
 }
 
-static void set_global_id(struct ceph_auth_client *ac, u64 global_id)
+void ceph_auth_set_global_id(struct ceph_auth_client *ac, u64 global_id)
 {
 	dout("%s global_id %llu\n", __func__, global_id);
 
@@ -260,19 +260,22 @@ int ceph_handle_auth_reply(struct ceph_auth_client *ac,
 		ac->negotiating = false;
 	}
 
-	ret = ac->ops->handle_reply(ac, result, payload, payload_end,
+	if (result) {
+		pr_err("auth protocol '%s' mauth authentication failed: %d\n",
+		       ceph_auth_proto_name(ac->protocol), result);
+		ret = result;
+		goto out;
+	}
+
+	ret = ac->ops->handle_reply(ac, global_id, payload, payload_end,
 				    NULL, NULL, NULL, NULL);
 	if (ret == -EAGAIN) {
 		ret = build_request(ac, true, reply_buf, reply_len);
 		goto out;
 	} else if (ret) {
-		pr_err("auth protocol '%s' mauth authentication failed: %d\n",
-		       ceph_auth_proto_name(ac->protocol), result);
 		goto out;
 	}
 
-	set_global_id(ac, global_id);
-
 out:
 	mutex_unlock(&ac->mutex);
 	return ret;
@@ -498,11 +501,10 @@ int ceph_auth_handle_reply_done(struct ceph_auth_client *ac,
 	int ret;
 
 	mutex_lock(&ac->mutex);
-	ret = ac->ops->handle_reply(ac, 0, reply, reply + reply_len,
+	ret = ac->ops->handle_reply(ac, global_id, reply, reply + reply_len,
 				    session_key, session_key_len,
 				    con_secret, con_secret_len);
-	if (!ret)
-		set_global_id(ac, global_id);
+	WARN_ON(ret == -EAGAIN || ret > 0);
 	mutex_unlock(&ac->mutex);
 	return ret;
 }

net/ceph/auth_none.c

@@ -69,15 +69,16 @@ static int build_request(struct ceph_auth_client *ac, void *buf, void *end)
  * the generic auth code decode the global_id, and we carry no actual
  * authenticate state, so nothing happens here.
  */
-static int handle_reply(struct ceph_auth_client *ac, int result,
+static int handle_reply(struct ceph_auth_client *ac, u64 global_id,
 			void *buf, void *end, u8 *session_key,
 			int *session_key_len, u8 *con_secret,
 			int *con_secret_len)
 {
 	struct ceph_auth_none_info *xi = ac->private;
 
 	xi->starting = false;
-	return result;
+	ceph_auth_set_global_id(ac, global_id);
+	return 0;
 }
 
 static void ceph_auth_none_destroy_authorizer(struct ceph_authorizer *a)

net/ceph/auth_x.c

@@ -597,7 +597,7 @@ static int decode_con_secret(void **p, void *end, u8 *con_secret,
 	return -EINVAL;
 }
 
-static int handle_auth_session_key(struct ceph_auth_client *ac,
+static int handle_auth_session_key(struct ceph_auth_client *ac, u64 global_id,
 				   void **p, void *end,
 				   u8 *session_key, int *session_key_len,
 				   u8 *con_secret, int *con_secret_len)
@@ -613,6 +613,7 @@ static int handle_auth_session_key(struct ceph_auth_client *ac,
 	if (ret)
 		return ret;
 
+	ceph_auth_set_global_id(ac, global_id);
 	if (*p == end) {
 		/* pre-nautilus (or didn't request service tickets!) */
 		WARN_ON(session_key || con_secret);
@@ -661,21 +662,19 @@ static int handle_auth_session_key(struct ceph_auth_client *ac,
 	return -EINVAL;
 }
 
-static int ceph_x_handle_reply(struct ceph_auth_client *ac, int result,
+static int ceph_x_handle_reply(struct ceph_auth_client *ac, u64 global_id,
 			       void *buf, void *end,
 			       u8 *session_key, int *session_key_len,
 			       u8 *con_secret, int *con_secret_len)
 {
 	struct ceph_x_info *xi = ac->private;
 	struct ceph_x_ticket_handler *th;
 	int len = end - buf;
+	int result;
 	void *p;
 	int op;
 	int ret;
 
-	if (result)
-		return result;  /* XXX hmm? */
-
 	if (xi->starting) {
 		/* it's a hello */
 		struct ceph_x_server_challenge *sc = buf;
@@ -697,9 +696,9 @@ static int ceph_x_handle_reply(struct ceph_auth_client *ac, int result,
 	switch (op) {
 	case CEPHX_GET_AUTH_SESSION_KEY:
 		/* AUTH ticket + [connection secret] + service tickets */
-		ret = handle_auth_session_key(ac, &p, end, session_key,
-					      session_key_len, con_secret,
-					      con_secret_len);
+		ret = handle_auth_session_key(ac, global_id, &p, end,
+					      session_key, session_key_len,
+					      con_secret, con_secret_len);
 		break;
 
 	case CEPHX_GET_PRINCIPAL_SESSION_KEY: