Documentation: bpf: Convert external kernel docs link

Convert links to other docs pages that use external links into
internal cross-references.

Signed-off-by: Bagas Sanjaya <[email protected]>

Author: bagasme

Documentation/bpf/bpf_iterators.rst

@@ -123,8 +123,7 @@ which often takes time to publish upstream and release. The same is true for pop
 tools like `ss <https://man7.org/linux/man-pages/man8/ss.8.html>`_ where any
 additional information needs a kernel patch.
 
-To solve this problem, the `drgn
-<https://www.kernel.org/doc/html/latest/bpf/drgn.html>`_ tool is often used to
+To solve this problem, the :doc:`drgn <drgn>` tool is often used to
 dig out the kernel data with no kernel change. However, the main drawback for
 drgn is performance, as it cannot do pointer tracing inside the kernel. In
 addition, drgn cannot validate a pointer value and may read invalid data if the

Documentation/bpf/map_xskmap.rst

@@ -10,7 +10,7 @@ BPF_MAP_TYPE_XSKMAP
 
 The ``BPF_MAP_TYPE_XSKMAP`` is used as a backend map for XDP BPF helper
 call ``bpf_redirect_map()`` and ``XDP_REDIRECT`` action, like 'devmap' and 'cpumap'.
-This map type redirects raw XDP frames to `AF_XDP`_ sockets (XSKs), a new type of
+This map type redirects raw XDP frames to AF_XDP sockets (XSKs), a new type of
 address family in the kernel that allows redirection of frames from a driver to
 user space without having to traverse the full network stack. An AF_XDP socket
 binds to a single netdev queue. A mapping of XSKs to queues is shown below:
@@ -181,12 +181,11 @@ AF_XDP-forwarding programs in the `bpf-examples`_ directory in the `libxdp`_ rep
 For a detailed explanation of the AF_XDP interface please see:
 
 - `libxdp-readme`_.
-- `AF_XDP`_ kernel documentation.
+- Documentation/networking/af_xdp.rst.
 
 .. note::
     The most comprehensive resource for using XSKMAPs and AF_XDP is `libxdp`_.
 
 .. _libxdp: https://github.com/xdp-project/xdp-tools/tree/master/lib/libxdp
-.. _AF_XDP: https://www.kernel.org/doc/html/latest/networking/af_xdp.html
 .. _bpf-examples: https://github.com/xdp-project/bpf-examples
 .. _libxdp-readme: https://github.com/xdp-project/xdp-tools/tree/master/lib/libxdp#using-af_xdp-sockets