diff options
| author | Gao Feng <fgao@ikuai8.com> | 2017-04-04 16:09:48 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-04-05 17:50:32 +0300 |
| commit | 589c49cbf9674808fd4ac9b7c17155abc0686f86 (patch) | |
| tree | 7065ecc4a28f72a6fd73570a0b793d92fee62e88 /net/ipv4 | |
| parent | 5e351410667ab0bf0dd1845730cba8b2211781e7 (diff) | |
| download | linux-589c49cbf9674808fd4ac9b7c17155abc0686f86.tar.xz | |
net: tcp: Define the TCP_MAX_WSCALE instead of literal number 14
Define one new macro TCP_MAX_WSCALE instead of literal number '14',
and use U16_MAX instead of 65535 as the max value of TCP window.
There is another minor change, use rounddown(space, mss) instead of
(space / mss) * mss;
Signed-off-by: Gao Feng <fgao@ikuai8.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4')
| -rw-r--r-- | net/ipv4/tcp.c | 2 | ||||
| -rw-r--r-- | net/ipv4/tcp_input.c | 9 | ||||
| -rw-r--r-- | net/ipv4/tcp_output.c | 12 |
3 files changed, 11 insertions, 12 deletions
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 1665948dff8c..94f0b5b50e0d 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -2393,7 +2393,7 @@ static int tcp_repair_options_est(struct tcp_sock *tp, u16 snd_wscale = opt.opt_val & 0xFFFF; u16 rcv_wscale = opt.opt_val >> 16; - if (snd_wscale > 14 || rcv_wscale > 14) + if (snd_wscale > TCP_MAX_WSCALE || rcv_wscale > TCP_MAX_WSCALE) return -EFBIG; tp->rx_opt.snd_wscale = snd_wscale; diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index a75c48f62e27..ed6606cf5b3e 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -3759,11 +3759,12 @@ void tcp_parse_options(const struct sk_buff *skb, !estab && sysctl_tcp_window_scaling) { __u8 snd_wscale = *(__u8 *)ptr; opt_rx->wscale_ok = 1; - if (snd_wscale > 14) { - net_info_ratelimited("%s: Illegal window scaling value %d >14 received\n", + if (snd_wscale > TCP_MAX_WSCALE) { + net_info_ratelimited("%s: Illegal window scaling value %d > %u received\n", __func__, - snd_wscale); - snd_wscale = 14; + snd_wscale, + TCP_MAX_WSCALE); + snd_wscale = TCP_MAX_WSCALE; } opt_rx->snd_wscale = snd_wscale; } diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index 13971942211b..0e807a83c1bc 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -212,12 +212,12 @@ void tcp_select_initial_window(int __space, __u32 mss, /* If no clamp set the clamp to the max possible scaled window */ if (*window_clamp == 0) - (*window_clamp) = (65535 << 14); + (*window_clamp) = (U16_MAX << TCP_MAX_WSCALE); space = min(*window_clamp, space); /* Quantize space offering to a multiple of mss if possible. */ if (space > mss) - space = (space / mss) * mss; + space = rounddown(space, mss); /* NOTE: offering an initial window larger than 32767 * will break some buggy TCP stacks. If the admin tells us @@ -234,13 +234,11 @@ void tcp_select_initial_window(int __space, __u32 mss, (*rcv_wscale) = 0; if (wscale_ok) { - /* Set window scaling on max possible window - * See RFC1323 for an explanation of the limit to 14 - */ + /* Set window scaling on max possible window */ space = max_t(u32, space, sysctl_tcp_rmem[2]); space = max_t(u32, space, sysctl_rmem_max); space = min_t(u32, space, *window_clamp); - while (space > 65535 && (*rcv_wscale) < 14) { + while (space > U16_MAX && (*rcv_wscale) < TCP_MAX_WSCALE) { space >>= 1; (*rcv_wscale)++; } @@ -253,7 +251,7 @@ void tcp_select_initial_window(int __space, __u32 mss, } /* Set the clamp no higher than max representable value */ - (*window_clamp) = min(65535U << (*rcv_wscale), *window_clamp); + (*window_clamp) = min_t(__u32, U16_MAX << (*rcv_wscale), *window_clamp); } EXPORT_SYMBOL(tcp_select_initial_window); |