xref: /linux/fs/smb/server/mgmt/tree_connect.c (revision c17ee635fd3a482b2ad2bf5e269755c2eae5f25e)
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 #include "../stats.h"
13 
14 #include "tree_connect.h"
15 #include "user_config.h"
16 #include "share_config.h"
17 #include "user_session.h"
18 
19 struct ksmbd_tree_conn_status
20 ksmbd_tree_conn_connect(struct ksmbd_work *work, 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 	struct ksmbd_conn *conn = work->conn;
28 	struct ksmbd_session *sess = work->sess;
29 	int ret;
30 
31 	sc = ksmbd_share_config_get(work, share_name);
32 	if (!sc)
33 		return status;
34 
35 	tree_conn = kzalloc_obj(struct ksmbd_tree_connect, KSMBD_DEFAULT_GFP);
36 	if (!tree_conn) {
37 		status.ret = -ENOMEM;
38 		goto out_error;
39 	}
40 
41 	tree_conn->id = ksmbd_acquire_tree_conn_id(sess);
42 	if (tree_conn->id < 0) {
43 		status.ret = -EINVAL;
44 		goto out_error;
45 	}
46 
47 	peer_addr = KSMBD_TCP_PEER_SOCKADDR(conn);
48 	resp = ksmbd_ipc_tree_connect_request(sess,
49 					      sc,
50 					      tree_conn,
51 					      peer_addr);
52 	if (!resp) {
53 		status.ret = -EINVAL;
54 		goto out_error;
55 	}
56 
57 	status.ret = resp->status;
58 	if (status.ret != KSMBD_TREE_CONN_STATUS_OK)
59 		goto out_error;
60 
61 	tree_conn->flags = resp->connection_flags;
62 	if (test_tree_conn_flag(tree_conn, KSMBD_TREE_CONN_FLAG_UPDATE)) {
63 		struct ksmbd_share_config *new_sc;
64 
65 		ksmbd_share_config_del(sc);
66 		new_sc = ksmbd_share_config_get(work, share_name);
67 		if (!new_sc) {
68 			pr_err("Failed to update stale share config\n");
69 			status.ret = -ESTALE;
70 			goto out_error;
71 		}
72 		ksmbd_share_config_put(sc);
73 		sc = new_sc;
74 	}
75 
76 	tree_conn->user = sess->user;
77 	tree_conn->share_conf = sc;
78 	tree_conn->t_state = TREE_NEW;
79 	status.tree_conn = tree_conn;
80 	atomic_set(&tree_conn->refcount, 1);
81 
82 	down_write(&sess->tree_conns_lock);
83 	ret = xa_err(xa_store(&sess->tree_conns, tree_conn->id, tree_conn,
84 			      KSMBD_DEFAULT_GFP));
85 	up_write(&sess->tree_conns_lock);
86 	if (ret) {
87 		status.ret = -ENOMEM;
88 		goto out_error;
89 	}
90 	ksmbd_counter_inc(KSMBD_COUNTER_TREE_CONNS);
91 	kvfree(resp);
92 	return status;
93 
94 out_error:
95 	if (tree_conn)
96 		ksmbd_release_tree_conn_id(sess, tree_conn->id);
97 	ksmbd_share_config_put(sc);
98 	kfree(tree_conn);
99 	kvfree(resp);
100 	return status;
101 }
102 
103 void ksmbd_tree_connect_put(struct ksmbd_tree_connect *tcon)
104 {
105 	if (atomic_dec_and_test(&tcon->refcount))
106 		kfree(tcon);
107 }
108 
109 static int __ksmbd_tree_conn_disconnect(struct ksmbd_session *sess,
110 					struct ksmbd_tree_connect *tree_conn)
111 {
112 	int ret;
113 
114 	ret = ksmbd_ipc_tree_disconnect_request(sess->id, tree_conn->id);
115 	ksmbd_release_tree_conn_id(sess, tree_conn->id);
116 	ksmbd_share_config_put(tree_conn->share_conf);
117 	ksmbd_counter_dec(KSMBD_COUNTER_TREE_CONNS);
118 	if (atomic_dec_and_test(&tree_conn->refcount))
119 		kfree(tree_conn);
120 	return ret;
121 }
122 
123 int ksmbd_tree_conn_disconnect(struct ksmbd_session *sess,
124 			       struct ksmbd_tree_connect *tree_conn)
125 {
126 	down_write(&sess->tree_conns_lock);
127 	xa_erase(&sess->tree_conns, tree_conn->id);
128 	up_write(&sess->tree_conns_lock);
129 
130 	return __ksmbd_tree_conn_disconnect(sess, tree_conn);
131 }
132 
133 struct ksmbd_tree_connect *ksmbd_tree_conn_lookup(struct ksmbd_session *sess,
134 						  unsigned int id)
135 {
136 	struct ksmbd_tree_connect *tcon;
137 
138 	down_read(&sess->tree_conns_lock);
139 	tcon = xa_load(&sess->tree_conns, id);
140 	if (tcon) {
141 		if (tcon->t_state != TREE_CONNECTED)
142 			tcon = NULL;
143 		else if (!atomic_inc_not_zero(&tcon->refcount))
144 			tcon = NULL;
145 	}
146 	up_read(&sess->tree_conns_lock);
147 
148 	return tcon;
149 }
150 
151 int ksmbd_tree_conn_session_logoff(struct ksmbd_session *sess)
152 {
153 	int ret = 0;
154 	struct ksmbd_tree_connect *tc;
155 	unsigned long id;
156 
157 	if (!sess)
158 		return -EINVAL;
159 
160 	down_write(&sess->tree_conns_lock);
161 	xa_for_each(&sess->tree_conns, id, tc) {
162 		if (tc->t_state == TREE_DISCONNECTED) {
163 			ret = -ENOENT;
164 			continue;
165 		}
166 		tc->t_state = TREE_DISCONNECTED;
167 
168 		xa_erase(&sess->tree_conns, tc->id);
169 		ret |= __ksmbd_tree_conn_disconnect(sess, tc);
170 	}
171 	xa_destroy(&sess->tree_conns);
172 	up_write(&sess->tree_conns_lock);
173 
174 	return ret;
175 }
176