summaryrefslogtreecommitdiff
path: root/compat/backport-4.4.c
blob: 660d50baf2f9e1a60ecf0b3640d4ef97e1c5dbf6 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
/*
 * Copyright(c) 2015 Intel Deutschland GmbH
 *
 * Backport functionality introduced in Linux 4.4.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#include <linux/debugfs.h>
#include <linux/export.h>
#include <linux/uaccess.h>
#include <linux/fs.h>
#include <linux/if_vlan.h>
#include <linux/mm.h>
#include <linux/skbuff.h>
#include <net/ip.h>
#include <net/tso.h>
#include <asm/unaligned.h>

#ifdef CONFIG_DEBUG_FS
#if LINUX_VERSION_IS_LESS(4,3,0)
static ssize_t debugfs_read_file_bool(struct file *file, char __user *user_buf,
				      size_t count, loff_t *ppos)
{
	char buf[3];
	bool *val = file->private_data;

	if (*val)
		buf[0] = 'Y';
	else
		buf[0] = 'N';
	buf[1] = '\n';
	buf[2] = 0x00;
	return simple_read_from_buffer(user_buf, count, ppos, buf, 2);
}

static ssize_t debugfs_write_file_bool(struct file *file,
				       const char __user *user_buf,
				       size_t count, loff_t *ppos)
{
	char buf[32];
	size_t buf_size;
	bool bv;
	bool *val = file->private_data;

	buf_size = min(count, (sizeof(buf)-1));
	if (copy_from_user(buf, user_buf, buf_size))
		return -EFAULT;

	buf[buf_size] = '\0';
	if (strtobool(buf, &bv) == 0)
		*val = bv;

	return count;
}
#endif /* < 4.3.0 */

static const struct file_operations fops_bool = {
	.read =		debugfs_read_file_bool,
	.write =	debugfs_write_file_bool,
	.open =		simple_open,
	.llseek =	default_llseek,
};

struct dentry *debugfs_create_bool(const char *name, umode_t mode,
				   struct dentry *parent, bool *value)
{
	return debugfs_create_file(name, mode, parent, value, &fops_bool);
}
EXPORT_SYMBOL_GPL(debugfs_create_bool);
#endif /* CONFIG_DEBUG_FS */

/* Calculate expected number of TX descriptors */
int tso_count_descs(struct sk_buff *skb)
{
	/* The Marvell Way */
	return skb_shinfo(skb)->gso_segs * 2 + skb_shinfo(skb)->nr_frags;
}
EXPORT_SYMBOL(tso_count_descs);

void tso_build_hdr(struct sk_buff *skb, char *hdr, struct tso_t *tso,
		   int size, bool is_last)
{
	struct tcphdr *tcph;
	int hdr_len = skb_transport_offset(skb) + tcp_hdrlen(skb);
	int mac_hdr_len = skb_network_offset(skb);

	memcpy(hdr, skb->data, hdr_len);
	if (!tso->ipv6) {
		struct iphdr *iph = (void *)(hdr + mac_hdr_len);

		iph->id = htons(tso->ip_id);
		iph->tot_len = htons(size + hdr_len - mac_hdr_len);
		tso->ip_id++;
	} else {
		struct ipv6hdr *iph = (void *)(hdr + mac_hdr_len);

		iph->payload_len = htons(size + tcp_hdrlen(skb));
	}
	tcph = (struct tcphdr *)(hdr + skb_transport_offset(skb));
	put_unaligned_be32(tso->tcp_seq, &tcph->seq);

	if (!is_last) {
		/* Clear all special flags for not last packet */
		tcph->psh = 0;
		tcph->fin = 0;
		tcph->rst = 0;
	}
}
EXPORT_SYMBOL(tso_build_hdr);

void tso_build_data(struct sk_buff *skb, struct tso_t *tso, int size)
{
	tso->tcp_seq += size;
	tso->size -= size;
	tso->data += size;

	if ((tso->size == 0) &&
	    (tso->next_frag_idx < skb_shinfo(skb)->nr_frags)) {
		skb_frag_t *frag = &skb_shinfo(skb)->frags[tso->next_frag_idx];

		/* Move to next segment */
		tso->size = frag->size;
		tso->data = page_address(skb_frag_page(frag)) + frag->page_offset;
		tso->next_frag_idx++;
	}
}
EXPORT_SYMBOL(tso_build_data);

void tso_start(struct sk_buff *skb, struct tso_t *tso)
{
	int hdr_len = skb_transport_offset(skb) + tcp_hdrlen(skb);

	tso->ip_id = ntohs(ip_hdr(skb)->id);
	tso->tcp_seq = ntohl(tcp_hdr(skb)->seq);
	tso->next_frag_idx = 0;
	tso->ipv6 = vlan_get_protocol(skb) == htons(ETH_P_IPV6);

	/* Build first data */
	tso->size = skb_headlen(skb) - hdr_len;
	tso->data = skb->data + hdr_len;
	if ((tso->size == 0) &&
	    (tso->next_frag_idx < skb_shinfo(skb)->nr_frags)) {
		skb_frag_t *frag = &skb_shinfo(skb)->frags[tso->next_frag_idx];

		/* Move to next segment */
		tso->size = frag->size;
		tso->data = page_address(skb_frag_page(frag)) + frag->page_offset;
		tso->next_frag_idx++;
	}
}
EXPORT_SYMBOL(tso_start);

const char *kvasprintf_const(gfp_t gfp, const char *fmt, va_list ap)
{
	if (!strchr(fmt, '%'))
		return kstrdup_const(fmt, gfp);
	if (!strcmp(fmt, "%s"))
		return kstrdup_const(va_arg(ap, const char*), gfp);
	return kvasprintf(gfp, fmt, ap);
}
EXPORT_SYMBOL(kvasprintf_const);