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