d5e7d19683
Yunsheng Lin says: ==================== net: introduce skb_frag_fill_page_desc() Most users use __skb_frag_set_page()/skb_frag_off_set()/ skb_frag_size_set() to fill the page desc for a skb frag. It does not make much sense to calling __skb_frag_set_page() without calling skb_frag_off_set(), as the offset may depend on whether the page is head page or tail page, so add skb_frag_fill_page_desc() to fill the page desc for a skb frag. In the future, we can make sure the page in the frag is head page of compound page or a base page, if not, we may warn about that and convert the tail page to head page and update the offset accordingly, if we see a warning about that, we also fix the caller to fill the head page in the frag. when the fixing is done, we may remove the warning and converting. In this way, we can remove the compound_head() or use page_ref_*() like the below case: https://elixir.bootlin.com/linux/latest/source/net/core/page_pool.c#L881 https://elixir.bootlin.com/linux/latest/source/include/linux/skbuff.h#L3383 It may also convert net stack to use the folio easier. V1: repost with all the ack/review tags included. RFC: remove a local variable as pointed out by Simon. ==================== Signed-off-by: David S. Miller <davem@davemloft.net>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.