1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 *   Copyright (C) 2018 Samsung Electronics Co., Ltd.
4 */
5
6#include <linux/list.h>
7#include <linux/slab.h>
8#include <linux/xarray.h>
9
10#include "../transport_ipc.h"
11#include "../connection.h"
12
13#include "tree_connect.h"
14#include "user_config.h"
15#include "share_config.h"
16#include "user_session.h"
17
18struct ksmbd_tree_conn_status
19ksmbd_tree_conn_connect(struct ksmbd_conn *conn, struct ksmbd_session *sess,
20			const char *share_name)
21{
22	struct ksmbd_tree_conn_status status = {-ENOENT, NULL};
23	struct ksmbd_tree_connect_response *resp = NULL;
24	struct ksmbd_share_config *sc;
25	struct ksmbd_tree_connect *tree_conn = NULL;
26	struct sockaddr *peer_addr;
27	int ret;
28
29	sc = ksmbd_share_config_get(conn->um, share_name);
30	if (!sc)
31		return status;
32
33	tree_conn = kzalloc(sizeof(struct ksmbd_tree_connect), GFP_KERNEL);
34	if (!tree_conn) {
35		status.ret = -ENOMEM;
36		goto out_error;
37	}
38
39	tree_conn->id = ksmbd_acquire_tree_conn_id(sess);
40	if (tree_conn->id < 0) {
41		status.ret = -EINVAL;
42		goto out_error;
43	}
44
45	peer_addr = KSMBD_TCP_PEER_SOCKADDR(conn);
46	resp = ksmbd_ipc_tree_connect_request(sess,
47					      sc,
48					      tree_conn,
49					      peer_addr);
50	if (!resp) {
51		status.ret = -EINVAL;
52		goto out_error;
53	}
54
55	status.ret = resp->status;
56	if (status.ret != KSMBD_TREE_CONN_STATUS_OK)
57		goto out_error;
58
59	tree_conn->flags = resp->connection_flags;
60	if (test_tree_conn_flag(tree_conn, KSMBD_TREE_CONN_FLAG_UPDATE)) {
61		struct ksmbd_share_config *new_sc;
62
63		ksmbd_share_config_del(sc);
64		new_sc = ksmbd_share_config_get(conn->um, share_name);
65		if (!new_sc) {
66			pr_err("Failed to update stale share config\n");
67			status.ret = -ESTALE;
68			goto out_error;
69		}
70		ksmbd_share_config_put(sc);
71		sc = new_sc;
72	}
73
74	tree_conn->user = sess->user;
75	tree_conn->share_conf = sc;
76	tree_conn->t_state = TREE_NEW;
77	status.tree_conn = tree_conn;
78	atomic_set(&tree_conn->refcount, 1);
79	init_waitqueue_head(&tree_conn->refcount_q);
80
81	ret = xa_err(xa_store(&sess->tree_conns, tree_conn->id, tree_conn,
82			      GFP_KERNEL));
83	if (ret) {
84		status.ret = -ENOMEM;
85		goto out_error;
86	}
87	kvfree(resp);
88	return status;
89
90out_error:
91	if (tree_conn)
92		ksmbd_release_tree_conn_id(sess, tree_conn->id);
93	ksmbd_share_config_put(sc);
94	kfree(tree_conn);
95	kvfree(resp);
96	return status;
97}
98
99void ksmbd_tree_connect_put(struct ksmbd_tree_connect *tcon)
100{
101	/*
102	 * Checking waitqueue to releasing tree connect on
103	 * tree disconnect. waitqueue_active is safe because it
104	 * uses atomic operation for condition.
105	 */
106	if (!atomic_dec_return(&tcon->refcount) &&
107	    waitqueue_active(&tcon->refcount_q))
108		wake_up(&tcon->refcount_q);
109}
110
111int ksmbd_tree_conn_disconnect(struct ksmbd_session *sess,
112			       struct ksmbd_tree_connect *tree_conn)
113{
114	int ret;
115
116	write_lock(&sess->tree_conns_lock);
117	xa_erase(&sess->tree_conns, tree_conn->id);
118	write_unlock(&sess->tree_conns_lock);
119
120	if (!atomic_dec_and_test(&tree_conn->refcount))
121		wait_event(tree_conn->refcount_q,
122			   atomic_read(&tree_conn->refcount) == 0);
123
124	ret = ksmbd_ipc_tree_disconnect_request(sess->id, tree_conn->id);
125	ksmbd_release_tree_conn_id(sess, tree_conn->id);
126	ksmbd_share_config_put(tree_conn->share_conf);
127	kfree(tree_conn);
128	return ret;
129}
130
131struct ksmbd_tree_connect *ksmbd_tree_conn_lookup(struct ksmbd_session *sess,
132						  unsigned int id)
133{
134	struct ksmbd_tree_connect *tcon;
135
136	read_lock(&sess->tree_conns_lock);
137	tcon = xa_load(&sess->tree_conns, id);
138	if (tcon) {
139		if (tcon->t_state != TREE_CONNECTED)
140			tcon = NULL;
141		else if (!atomic_inc_not_zero(&tcon->refcount))
142			tcon = NULL;
143	}
144	read_unlock(&sess->tree_conns_lock);
145
146	return tcon;
147}
148
149int ksmbd_tree_conn_session_logoff(struct ksmbd_session *sess)
150{
151	int ret = 0;
152	struct ksmbd_tree_connect *tc;
153	unsigned long id;
154
155	if (!sess)
156		return -EINVAL;
157
158	xa_for_each(&sess->tree_conns, id, tc) {
159		write_lock(&sess->tree_conns_lock);
160		if (tc->t_state == TREE_DISCONNECTED) {
161			write_unlock(&sess->tree_conns_lock);
162			ret = -ENOENT;
163			continue;
164		}
165		tc->t_state = TREE_DISCONNECTED;
166		write_unlock(&sess->tree_conns_lock);
167
168		ret |= ksmbd_tree_conn_disconnect(sess, tc);
169	}
170	xa_destroy(&sess->tree_conns);
171	return ret;
172}
173