1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  *	Skb ref helpers.
4  *
5  */
6 
7 #ifndef _LINUX_SKBUFF_REF_H
8 #define _LINUX_SKBUFF_REF_H
9 
10 #include <linux/skbuff.h>
11 
12 /**
13  * __skb_frag_ref - take an addition reference on a paged fragment.
14  * @frag: the paged fragment
15  *
16  * Takes an additional reference on the paged fragment @frag.
17  */
__skb_frag_ref(skb_frag_t * frag)18 static inline void __skb_frag_ref(skb_frag_t *frag)
19 {
20 	get_page(skb_frag_page(frag));
21 }
22 
23 /**
24  * skb_frag_ref - take an addition reference on a paged fragment of an skb.
25  * @skb: the buffer
26  * @f: the fragment offset.
27  *
28  * Takes an additional reference on the @f'th paged fragment of @skb.
29  */
skb_frag_ref(struct sk_buff * skb,int f)30 static inline void skb_frag_ref(struct sk_buff *skb, int f)
31 {
32 	__skb_frag_ref(&skb_shinfo(skb)->frags[f]);
33 }
34 
35 bool napi_pp_put_page(netmem_ref netmem);
36 
skb_page_unref(netmem_ref netmem,bool recycle)37 static inline void skb_page_unref(netmem_ref netmem, bool recycle)
38 {
39 #ifdef CONFIG_PAGE_POOL
40 	if (recycle && napi_pp_put_page(netmem))
41 		return;
42 #endif
43 	put_page(netmem_to_page(netmem));
44 }
45 
46 /**
47  * __skb_frag_unref - release a reference on a paged fragment.
48  * @frag: the paged fragment
49  * @recycle: recycle the page if allocated via page_pool
50  *
51  * Releases a reference on the paged fragment @frag
52  * or recycles the page via the page_pool API.
53  */
__skb_frag_unref(skb_frag_t * frag,bool recycle)54 static inline void __skb_frag_unref(skb_frag_t *frag, bool recycle)
55 {
56 	skb_page_unref(skb_frag_netmem(frag), recycle);
57 }
58 
59 /**
60  * skb_frag_unref - release a reference on a paged fragment of an skb.
61  * @skb: the buffer
62  * @f: the fragment offset
63  *
64  * Releases a reference on the @f'th paged fragment of @skb.
65  */
skb_frag_unref(struct sk_buff * skb,int f)66 static inline void skb_frag_unref(struct sk_buff *skb, int f)
67 {
68 	struct skb_shared_info *shinfo = skb_shinfo(skb);
69 
70 	if (!skb_zcopy_managed(skb))
71 		__skb_frag_unref(&shinfo->frags[f], skb->pp_recycle);
72 }
73 
74 #endif	/* _LINUX_SKBUFF_REF_H */
75