linux-next/include/linux/skbuff_ref.h
Mina Almasry 4dec64c52e page_pool: convert to use netmem
Abstract the memory type from the page_pool so we can later add support
for new memory types. Convert the page_pool to use the new netmem type
abstraction, rather than use struct page directly.

As of this patch the netmem type is a no-op abstraction: it's always a
struct page underneath. All the page pool internals are converted to
use struct netmem instead of struct page, and the page pool now exports
2 APIs:

1. The existing struct page API.
2. The new struct netmem API.

Keeping the existing API is transitional; we do not want to refactor all
the current drivers using the page pool at once.

The netmem abstraction is currently a no-op. The page_pool uses
page_to_netmem() to convert allocated pages to netmem, and uses
netmem_to_page() to convert the netmem back to pages to pass to mm APIs,

Follow up patches to this series add non-paged netmem support to the
page_pool. This change is factored out on its own to limit the code
churn to this 1 patch, for ease of code review.

Signed-off-by: Mina Almasry <almasrymina@google.com>
Reviewed-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://patch.msgid.link/20240628003253.1694510-6-almasrymina@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-07-02 18:59:33 -07:00

76 lines
1.7 KiB
C

/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* Skb ref helpers.
*
*/
#ifndef _LINUX_SKBUFF_REF_H
#define _LINUX_SKBUFF_REF_H
#include <linux/skbuff.h>
/**
* __skb_frag_ref - take an addition reference on a paged fragment.
* @frag: the paged fragment
*
* Takes an additional reference on the paged fragment @frag.
*/
static inline void __skb_frag_ref(skb_frag_t *frag)
{
get_page(skb_frag_page(frag));
}
/**
* skb_frag_ref - take an addition reference on a paged fragment of an skb.
* @skb: the buffer
* @f: the fragment offset.
*
* Takes an additional reference on the @f'th paged fragment of @skb.
*/
static inline void skb_frag_ref(struct sk_buff *skb, int f)
{
__skb_frag_ref(&skb_shinfo(skb)->frags[f]);
}
bool napi_pp_put_page(netmem_ref netmem);
static inline void
skb_page_unref(struct page *page, bool recycle)
{
#ifdef CONFIG_PAGE_POOL
if (recycle && napi_pp_put_page(page_to_netmem(page)))
return;
#endif
put_page(page);
}
/**
* __skb_frag_unref - release a reference on a paged fragment.
* @frag: the paged fragment
* @recycle: recycle the page if allocated via page_pool
*
* Releases a reference on the paged fragment @frag
* or recycles the page via the page_pool API.
*/
static inline void __skb_frag_unref(skb_frag_t *frag, bool recycle)
{
skb_page_unref(skb_frag_page(frag), recycle);
}
/**
* skb_frag_unref - release a reference on a paged fragment of an skb.
* @skb: the buffer
* @f: the fragment offset
*
* Releases a reference on the @f'th paged fragment of @skb.
*/
static inline void skb_frag_unref(struct sk_buff *skb, int f)
{
struct skb_shared_info *shinfo = skb_shinfo(skb);
if (!skb_zcopy_managed(skb))
__skb_frag_unref(&shinfo->frags[f], skb->pp_recycle);
}
#endif /* _LINUX_SKBUFF_REF_H */