 a0376db0f2
			
		
	
	
	a0376db0f2
	
	
	
		
			
			Do not convert endian back and forth. If the caller uses contant "mask" argument (and most callers do), we can omit runtime endian conversion here. Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org> Signed-off-by: David S. Miller <davem@davemloft.net>
		
			
				
	
	
		
			52 lines
		
	
	
	
		
			1.1 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			52 lines
		
	
	
	
		
			1.1 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| /* include/net/dsfield.h - Manipulation of the Differentiated Services field */
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| 
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| /* Written 1998-2000 by Werner Almesberger, EPFL ICA */
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| 
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| 
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| #ifndef __NET_DSFIELD_H
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| #define __NET_DSFIELD_H
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| 
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| #include <linux/types.h>
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| #include <linux/ip.h>
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| #include <linux/ipv6.h>
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| #include <asm/byteorder.h>
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| 
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| 
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| static inline __u8 ipv4_get_dsfield(const struct iphdr *iph)
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| {
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| 	return iph->tos;
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| }
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| 
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| 
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| static inline __u8 ipv6_get_dsfield(const struct ipv6hdr *ipv6h)
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| {
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| 	return ntohs(*(const __be16 *)ipv6h) >> 4;
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| }
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| 
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| 
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| static inline void ipv4_change_dsfield(struct iphdr *iph,__u8 mask,
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|     __u8 value)
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| {
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|         __u32 check = ntohs((__force __be16)iph->check);
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| 	__u8 dsfield;
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| 
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| 	dsfield = (iph->tos & mask) | value;
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| 	check += iph->tos;
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| 	if ((check+1) >> 16) check = (check+1) & 0xffff;
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| 	check -= dsfield;
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| 	check += check >> 16; /* adjust carry */
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| 	iph->check = (__force __sum16)htons(check);
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| 	iph->tos = dsfield;
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| }
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| 
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| 
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| static inline void ipv6_change_dsfield(struct ipv6hdr *ipv6h,__u8 mask,
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|     __u8 value)
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| {
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| 	__be16 *p = (__force __be16 *)ipv6h;
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| 
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| 	*p = (*p & htons((((u16)mask << 4) | 0xf00f))) | htons((u16)value << 4);
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| }
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| 
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| 
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| #endif
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