include/linux/skbuff_ref.h

   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  */
  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  */
  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
  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  */
  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  */
  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 */