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33#include <linux/kernel.h>
34#include <linux/slab.h>
35#include <linux/in.h>
36#include <net/net_namespace.h>
37#include <net/netns/generic.h>
38#include <linux/ipv6.h>
39
40#include "rds_single_path.h"
41#include "rds.h"
42#include "loop.h"
43
44static DEFINE_SPINLOCK(loop_conns_lock);
45static LIST_HEAD(loop_conns);
46static atomic_t rds_loop_unloading = ATOMIC_INIT(0);
47
48static void rds_loop_set_unloading(void)
49{
50 atomic_set(&rds_loop_unloading, 1);
51}
52
53static bool rds_loop_is_unloading(struct rds_connection *conn)
54{
55 return atomic_read(&rds_loop_unloading) != 0;
56}
57
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73
74
75static int rds_loop_xmit(struct rds_connection *conn, struct rds_message *rm,
76 unsigned int hdr_off, unsigned int sg,
77 unsigned int off)
78{
79 struct scatterlist *sgp = &rm->data.op_sg[sg];
80 int ret = sizeof(struct rds_header) +
81 be32_to_cpu(rm->m_inc.i_hdr.h_len);
82
83
84 if (rm->m_inc.i_hdr.h_flags & RDS_FLAG_CONG_BITMAP) {
85 rds_cong_map_updated(conn->c_fcong, ~(u64) 0);
86 ret = min_t(int, ret, sgp->length - conn->c_xmit_data_off);
87 goto out;
88 }
89
90 BUG_ON(hdr_off || sg || off);
91
92 rds_inc_init(&rm->m_inc, conn, &conn->c_laddr);
93
94 rds_message_addref(rm);
95
96 rds_recv_incoming(conn, &conn->c_laddr, &conn->c_faddr, &rm->m_inc,
97 GFP_KERNEL);
98
99 rds_send_drop_acked(conn, be64_to_cpu(rm->m_inc.i_hdr.h_sequence),
100 NULL);
101
102 rds_inc_put(&rm->m_inc);
103out:
104 return ret;
105}
106
107
108
109
110
111static void rds_loop_inc_free(struct rds_incoming *inc)
112{
113 struct rds_message *rm = container_of(inc, struct rds_message, m_inc);
114
115 rds_message_put(rm);
116}
117
118
119static int rds_loop_recv_path(struct rds_conn_path *cp)
120{
121 return 0;
122}
123
124struct rds_loop_connection {
125 struct list_head loop_node;
126 struct rds_connection *conn;
127};
128
129
130
131
132
133
134
135static int rds_loop_conn_alloc(struct rds_connection *conn, gfp_t gfp)
136{
137 struct rds_loop_connection *lc;
138 unsigned long flags;
139
140 lc = kzalloc(sizeof(struct rds_loop_connection), gfp);
141 if (!lc)
142 return -ENOMEM;
143
144 INIT_LIST_HEAD(&lc->loop_node);
145 lc->conn = conn;
146 conn->c_transport_data = lc;
147
148 spin_lock_irqsave(&loop_conns_lock, flags);
149 list_add_tail(&lc->loop_node, &loop_conns);
150 spin_unlock_irqrestore(&loop_conns_lock, flags);
151
152 return 0;
153}
154
155static void rds_loop_conn_free(void *arg)
156{
157 struct rds_loop_connection *lc = arg;
158 unsigned long flags;
159
160 rdsdebug("lc %p\n", lc);
161 spin_lock_irqsave(&loop_conns_lock, flags);
162 list_del(&lc->loop_node);
163 spin_unlock_irqrestore(&loop_conns_lock, flags);
164 kfree(lc);
165}
166
167static int rds_loop_conn_path_connect(struct rds_conn_path *cp)
168{
169 rds_connect_complete(cp->cp_conn);
170 return 0;
171}
172
173static void rds_loop_conn_path_shutdown(struct rds_conn_path *cp)
174{
175}
176
177void rds_loop_exit(void)
178{
179 struct rds_loop_connection *lc, *_lc;
180 LIST_HEAD(tmp_list);
181
182 rds_loop_set_unloading();
183 synchronize_rcu();
184
185 spin_lock_irq(&loop_conns_lock);
186 list_splice(&loop_conns, &tmp_list);
187 INIT_LIST_HEAD(&loop_conns);
188 spin_unlock_irq(&loop_conns_lock);
189
190 list_for_each_entry_safe(lc, _lc, &tmp_list, loop_node) {
191 WARN_ON(lc->conn->c_passive);
192 rds_conn_destroy(lc->conn);
193 }
194}
195
196static void rds_loop_kill_conns(struct net *net)
197{
198 struct rds_loop_connection *lc, *_lc;
199 LIST_HEAD(tmp_list);
200
201 spin_lock_irq(&loop_conns_lock);
202 list_for_each_entry_safe(lc, _lc, &loop_conns, loop_node) {
203 struct net *c_net = read_pnet(&lc->conn->c_net);
204
205 if (net != c_net)
206 continue;
207 list_move_tail(&lc->loop_node, &tmp_list);
208 }
209 spin_unlock_irq(&loop_conns_lock);
210
211 list_for_each_entry_safe(lc, _lc, &tmp_list, loop_node) {
212 WARN_ON(lc->conn->c_passive);
213 rds_conn_destroy(lc->conn);
214 }
215}
216
217static void __net_exit rds_loop_exit_net(struct net *net)
218{
219 rds_loop_kill_conns(net);
220}
221
222static struct pernet_operations rds_loop_net_ops = {
223 .exit = rds_loop_exit_net,
224};
225
226int rds_loop_net_init(void)
227{
228 return register_pernet_device(&rds_loop_net_ops);
229}
230
231void rds_loop_net_exit(void)
232{
233 unregister_pernet_device(&rds_loop_net_ops);
234}
235
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240
241
242struct rds_transport rds_loop_transport = {
243 .xmit = rds_loop_xmit,
244 .recv_path = rds_loop_recv_path,
245 .conn_alloc = rds_loop_conn_alloc,
246 .conn_free = rds_loop_conn_free,
247 .conn_path_connect = rds_loop_conn_path_connect,
248 .conn_path_shutdown = rds_loop_conn_path_shutdown,
249 .inc_copy_to_user = rds_message_inc_copy_to_user,
250 .inc_free = rds_loop_inc_free,
251 .t_name = "loopback",
252 .t_type = RDS_TRANS_LOOP,
253 .t_unloading = rds_loop_is_unloading,
254};
255