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	W=1 builds now warn if module is built without a MODULE_DESCRIPTION(). Add descriptions to the network schedulers. Suggested-by: Jamal Hadi Salim <jhs@mojatatu.com> Signed-off-by: Breno Leitao <leitao@debian.org> Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com> Link: https://lore.kernel.org/r/20240208164244.3818498-8-leitao@debian.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
		
			
				
	
	
		
			96 lines
		
	
	
	
		
			2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			96 lines
		
	
	
	
		
			2 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
// SPDX-License-Identifier: GPL-2.0-or-later
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/*
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 * net/sched/em_cmp.c	Simple packet data comparison ematch
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 *
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 * Authors:	Thomas Graf <tgraf@suug.ch>
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 */
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#include <linux/module.h>
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#include <linux/types.h>
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#include <linux/kernel.h>
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#include <linux/skbuff.h>
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#include <linux/tc_ematch/tc_em_cmp.h>
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#include <asm/unaligned.h>
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#include <net/pkt_cls.h>
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static inline int cmp_needs_transformation(struct tcf_em_cmp *cmp)
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{
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	return unlikely(cmp->flags & TCF_EM_CMP_TRANS);
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}
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static int em_cmp_match(struct sk_buff *skb, struct tcf_ematch *em,
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			struct tcf_pkt_info *info)
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{
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	struct tcf_em_cmp *cmp = (struct tcf_em_cmp *) em->data;
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	unsigned char *ptr = tcf_get_base_ptr(skb, cmp->layer) + cmp->off;
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	u32 val = 0;
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	if (!tcf_valid_offset(skb, ptr, cmp->align))
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		return 0;
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	switch (cmp->align) {
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	case TCF_EM_ALIGN_U8:
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		val = *ptr;
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		break;
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	case TCF_EM_ALIGN_U16:
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		val = get_unaligned_be16(ptr);
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		if (cmp_needs_transformation(cmp))
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			val = be16_to_cpu(val);
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		break;
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	case TCF_EM_ALIGN_U32:
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		/* Worth checking boundaries? The branching seems
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		 * to get worse. Visit again.
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		 */
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		val = get_unaligned_be32(ptr);
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		if (cmp_needs_transformation(cmp))
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			val = be32_to_cpu(val);
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		break;
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	default:
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		return 0;
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	}
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	if (cmp->mask)
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		val &= cmp->mask;
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	switch (cmp->opnd) {
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	case TCF_EM_OPND_EQ:
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		return val == cmp->val;
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	case TCF_EM_OPND_LT:
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		return val < cmp->val;
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	case TCF_EM_OPND_GT:
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		return val > cmp->val;
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	}
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	return 0;
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}
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static struct tcf_ematch_ops em_cmp_ops = {
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	.kind	  = TCF_EM_CMP,
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	.datalen  = sizeof(struct tcf_em_cmp),
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	.match	  = em_cmp_match,
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	.owner	  = THIS_MODULE,
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	.link	  = LIST_HEAD_INIT(em_cmp_ops.link)
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};
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static int __init init_em_cmp(void)
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{
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	return tcf_em_register(&em_cmp_ops);
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}
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static void __exit exit_em_cmp(void)
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{
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	tcf_em_unregister(&em_cmp_ops);
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}
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MODULE_DESCRIPTION("ematch classifier for basic data types(8/16/32 bit) against skb data");
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MODULE_LICENSE("GPL");
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module_init(init_em_cmp);
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module_exit(exit_em_cmp);
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MODULE_ALIAS_TCF_EMATCH(TCF_EM_CMP);
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