1 /*
2  * Copyright (c) 2013, Cisco Systems, Inc. All rights reserved.
3  *
4  * This software is available to you under a choice of one of two
5  * licenses.  You may choose to be licensed under the terms of the GNU
6  * General Public License (GPL) Version 2, available from the file
7  * COPYING in the main directory of this source tree, or the
8  * BSD license below:
9  *
10  *     Redistribution and use in source and binary forms, with or
11  *     without modification, are permitted provided that the following
12  *     conditions are met:
13  *
14  *      - Redistributions of source code must retain the above
15  *        copyright notice, this list of conditions and the following
16  *        disclaimer.
17  *
18  *      - Redistributions in binary form must reproduce the above
19  *        copyright notice, this list of conditions and the following
20  *        disclaimer in the documentation and/or other materials
21  *        provided with the distribution.
22  *
23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30  * SOFTWARE.
31  *
32  */
33 #include <linux/bitmap.h>
34 #include <linux/file.h>
35 #include <linux/module.h>
36 #include <linux/slab.h>
37 #include <net/inet_sock.h>
38 
39 #include "usnic_transport.h"
40 #include "usnic_log.h"
41 
42 /* ROCE */
43 static unsigned long *roce_bitmap;
44 static u16 roce_next_port = 1;
45 #define ROCE_BITMAP_SZ ((1 << (8 /*CHAR_BIT*/ * sizeof(u16)))/8 /*CHAR BIT*/)
46 static DEFINE_SPINLOCK(roce_bitmap_lock);
47 
48 const char *usnic_transport_to_str(enum usnic_transport_type type)
49 {
50 	switch (type) {
51 	case USNIC_TRANSPORT_UNKNOWN:
52 		return "Unknown";
53 	case USNIC_TRANSPORT_ROCE_CUSTOM:
54 		return "roce custom";
55 	case USNIC_TRANSPORT_IPV4_UDP:
56 		return "IPv4 UDP";
57 	case USNIC_TRANSPORT_MAX:
58 		return "Max?";
59 	default:
60 		return "Not known";
61 	}
62 }
63 
64 int usnic_transport_sock_to_str(char *buf, int buf_sz,
65 					struct socket *sock)
66 {
67 	int err;
68 	uint32_t addr;
69 	uint16_t port;
70 	int proto;
71 
72 	memset(buf, 0, buf_sz);
73 	err = usnic_transport_sock_get_addr(sock, &proto, &addr, &port);
74 	if (err)
75 		return 0;
76 
77 	return scnprintf(buf, buf_sz, "Proto:%u Addr:%pI4h Port:%hu",
78 			proto, &addr, port);
79 }
80 
81 /*
82  * reserve a port number.  if "0" specified, we will try to pick one
83  * starting at roce_next_port.  roce_next_port will take on the values
84  * 1..4096
85  */
86 u16 usnic_transport_rsrv_port(enum usnic_transport_type type, u16 port_num)
87 {
88 	if (type == USNIC_TRANSPORT_ROCE_CUSTOM) {
89 		spin_lock(&roce_bitmap_lock);
90 		if (!port_num) {
91 			port_num = bitmap_find_next_zero_area(roce_bitmap,
92 						ROCE_BITMAP_SZ,
93 						roce_next_port /* start */,
94 						1 /* nr */,
95 						0 /* align */);
96 			roce_next_port = (port_num & 4095) + 1;
97 		} else if (test_bit(port_num, roce_bitmap)) {
98 			usnic_err("Failed to allocate port for %s\n",
99 					usnic_transport_to_str(type));
100 			spin_unlock(&roce_bitmap_lock);
101 			goto out_fail;
102 		}
103 		bitmap_set(roce_bitmap, port_num, 1);
104 		spin_unlock(&roce_bitmap_lock);
105 	} else {
106 		usnic_err("Failed to allocate port - transport %s unsupported\n",
107 				usnic_transport_to_str(type));
108 		goto out_fail;
109 	}
110 
111 	usnic_dbg("Allocating port %hu for %s\n", port_num,
112 			usnic_transport_to_str(type));
113 	return port_num;
114 
115 out_fail:
116 	return 0;
117 }
118 
119 void usnic_transport_unrsrv_port(enum usnic_transport_type type, u16 port_num)
120 {
121 	if (type == USNIC_TRANSPORT_ROCE_CUSTOM) {
122 		spin_lock(&roce_bitmap_lock);
123 		if (!port_num) {
124 			usnic_err("Unreserved unvalid port num 0 for %s\n",
125 					usnic_transport_to_str(type));
126 			goto out_roce_custom;
127 		}
128 
129 		if (!test_bit(port_num, roce_bitmap)) {
130 			usnic_err("Unreserving invalid %hu for %s\n",
131 					port_num,
132 					usnic_transport_to_str(type));
133 			goto out_roce_custom;
134 		}
135 		bitmap_clear(roce_bitmap, port_num, 1);
136 		usnic_dbg("Freeing port %hu for %s\n", port_num,
137 				usnic_transport_to_str(type));
138 out_roce_custom:
139 		spin_unlock(&roce_bitmap_lock);
140 	} else {
141 		usnic_err("Freeing invalid port %hu for %d\n", port_num, type);
142 	}
143 }
144 
145 struct socket *usnic_transport_get_socket(int sock_fd)
146 {
147 	struct socket *sock;
148 	int err;
149 	char buf[25];
150 
151 	/* sockfd_lookup will internally do a fget */
152 	sock = sockfd_lookup(sock_fd, &err);
153 	if (!sock) {
154 		usnic_err("Unable to lookup socket for fd %d with err %d\n",
155 				sock_fd, err);
156 		return ERR_PTR(-ENOENT);
157 	}
158 
159 	usnic_transport_sock_to_str(buf, sizeof(buf), sock);
160 	usnic_dbg("Get sock %s\n", buf);
161 
162 	return sock;
163 }
164 
165 void usnic_transport_put_socket(struct socket *sock)
166 {
167 	char buf[100];
168 
169 	usnic_transport_sock_to_str(buf, sizeof(buf), sock);
170 	usnic_dbg("Put sock %s\n", buf);
171 	sockfd_put(sock);
172 }
173 
174 int usnic_transport_sock_get_addr(struct socket *sock, int *proto,
175 					uint32_t *addr, uint16_t *port)
176 {
177 	int err;
178 	struct sockaddr_in sock_addr;
179 
180 	err = sock->ops->getname(sock,
181 				(struct sockaddr *)&sock_addr,
182 				0);
183 	if (err < 0)
184 		return err;
185 
186 	if (sock_addr.sin_family != AF_INET)
187 		return -EINVAL;
188 
189 	if (proto)
190 		*proto = sock->sk->sk_protocol;
191 	if (port)
192 		*port = ntohs(((struct sockaddr_in *)&sock_addr)->sin_port);
193 	if (addr)
194 		*addr = ntohl(((struct sockaddr_in *)
195 					&sock_addr)->sin_addr.s_addr);
196 
197 	return 0;
198 }
199 
200 int usnic_transport_init(void)
201 {
202 	roce_bitmap = kzalloc(ROCE_BITMAP_SZ, GFP_KERNEL);
203 	if (!roce_bitmap)
204 		return -ENOMEM;
205 
206 	/* Do not ever allocate bit 0, hence set it here */
207 	bitmap_set(roce_bitmap, 0, 1);
208 	return 0;
209 }
210 
211 void usnic_transport_fini(void)
212 {
213 	kfree(roce_bitmap);
214 }
215