docs/mm: remove useless markup

It is enough to use a file name to cross-reference another rst document.

Jon says:
  The right things will happen in the HTML output, readers of the
  plain-text will know immediately where to go, and we don't have to add
  the label clutter.

Drop reference markup and unnecessary labels and use plain file names.

Signed-off-by: Mike Rapoport (IBM) <rppt@kernel.org>
Link: https://lore.kernel.org/r/20230201094156.991542-3-rppt@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Documentation/mm/active_mm.rst

@@ -1,5 +1,3 @@
-.. _active_mm:
-
 =========
 Active MM
 =========

Documentation/mm/arch_pgtable_helpers.rst

@@ -1,7 +1,5 @@
 .. SPDX-License-Identifier: GPL-2.0
 
-.. _arch_page_table_helpers:
-
 ===============================
 Architecture Page Table Helpers
 ===============================

Documentation/mm/balance.rst

@@ -1,5 +1,3 @@
-.. _balance:
-
 ================
 Memory Balancing
 ================

Documentation/mm/free_page_reporting.rst

@@ -1,5 +1,3 @@
-.. _free_page_reporting:
-
 =====================
 Free Page Reporting
 =====================

Documentation/mm/frontswap.rst

@@ -1,5 +1,3 @@
-.. _frontswap:
-
 =========
 Frontswap
 =========

Documentation/mm/highmem.rst

@@ -1,5 +1,3 @@
-.. _highmem:
-
 ====================
 High Memory Handling
 ====================

Documentation/mm/hmm.rst

@@ -1,5 +1,3 @@
-.. _hmm:
-
 =====================================
 Heterogeneous Memory Management (HMM)
 =====================================
@@ -304,7 +302,7 @@ devm_memunmap_pages(), and devm_release_mem_region() when the resources can
 be tied to a ``struct device``.
 
 The overall migration steps are similar to migrating NUMA pages within system
-memory (see :ref:`Page migration <page_migration>`) but the steps are split
+memory (see Documentation/mm/page_migration.rst) but the steps are split
 between device driver specific code and shared common code:
 
 1. ``mmap_read_lock()``

Documentation/mm/hugetlbfs_reserv.rst

@@ -1,5 +1,3 @@
-.. _hugetlbfs_reserve:
-
 =====================
 Hugetlbfs Reservation
 =====================
@@ -7,7 +5,7 @@ Hugetlbfs Reservation
 Overview
 ========
 
-Huge pages as described at :ref:`hugetlbpage` are typically
+Huge pages as described at Documentation/mm/hugetlbpage.rst are typically
 preallocated for application use.  These huge pages are instantiated in a
 task's address space at page fault time if the VMA indicates huge pages are
 to be used.  If no huge page exists at page fault time, the task is sent

Documentation/mm/hwpoison.rst

@@ -1,5 +1,3 @@
-.. hwpoison:
-
 ========
 hwpoison
 ========

Documentation/mm/ksm.rst

@@ -1,5 +1,3 @@
-.. _ksm:
-
 =======================
 Kernel Samepage Merging
 =======================
@@ -8,7 +6,7 @@ KSM is a memory-saving de-duplication feature, enabled by CONFIG_KSM=y,
 added to the Linux kernel in 2.6.32.  See ``mm/ksm.c`` for its implementation,
 and http://lwn.net/Articles/306704/ and https://lwn.net/Articles/330589/
 
-The userspace interface of KSM is described in :ref:`Documentation/admin-guide/mm/ksm.rst <admin_guide_ksm>`
+The userspace interface of KSM is described in Documentation/admin-guide/mm/ksm.rst
 
 Design
 ======

Documentation/mm/memory-model.rst

@@ -1,7 +1,5 @@
 .. SPDX-License-Identifier: GPL-2.0
 
-.. _physical_memory_model:
-
 =====================
 Physical Memory Model
 =====================

Documentation/mm/mmu_notifier.rst

@@ -1,5 +1,3 @@
-.. _mmu_notifier:
-
 When do you need to notify inside page table lock ?
 ===================================================
 

Documentation/mm/numa.rst

@@ -1,5 +1,3 @@
-.. _numa:
-
 Started Nov 1999 by Kanoj Sarcar <kanoj@sgi.com>
 
 =============
@@ -110,7 +108,7 @@ to improve NUMA locality using various CPU affinity command line interfaces,
 such as taskset(1) and numactl(1), and program interfaces such as
 sched_setaffinity(2).  Further, one can modify the kernel's default local
 allocation behavior using Linux NUMA memory policy. [see
-:ref:`Documentation/admin-guide/mm/numa_memory_policy.rst <numa_memory_policy>`].
+Documentation/admin-guide/mm/numa_memory_policy.rst].
 
 System administrators can restrict the CPUs and nodes' memories that a non-
 privileged user can specify in the scheduling or NUMA commands and functions

Documentation/mm/page_frags.rst

@@ -1,5 +1,3 @@
-.. _page_frags:
-
 ==============
 Page fragments
 ==============

Documentation/mm/page_migration.rst

@@ -1,5 +1,3 @@
-.. _page_migration:
-
 ==============
 Page migration
 ==============
@@ -9,8 +7,8 @@ nodes in a NUMA system while the process is running. This means that the
 virtual addresses that the process sees do not change. However, the
 system rearranges the physical location of those pages.
 
-Also see :ref:`Heterogeneous Memory Management (HMM) <hmm>`
-for migrating pages to or from device private memory.
+Also see Documentation/mm/hmm.rst for migrating pages to or from device
+private memory.
 
 The main intent of page migration is to reduce the latency of memory accesses
 by moving pages near to the processor where the process accessing that memory

Documentation/mm/page_owner.rst

@@ -1,5 +1,3 @@
-.. _page_owner:
-
 ==================================================
 page owner: Tracking about who allocated each page
 ==================================================

Documentation/mm/page_table_check.rst

@@ -1,7 +1,5 @@
 .. SPDX-License-Identifier: GPL-2.0
 
-.. _page_table_check:
-
 ================
 Page Table Check
 ================

Documentation/mm/remap_file_pages.rst

@@ -1,5 +1,3 @@
-.. _remap_file_pages:
-
 ==============================
 remap_file_pages() system call
 ==============================

Documentation/mm/slub.rst

@@ -1,5 +1,3 @@
-.. _slub:
-
 ==========================
 Short users guide for SLUB
 ==========================

Documentation/mm/split_page_table_lock.rst

@@ -1,5 +1,3 @@
-.. _split_page_table_lock:
-
 =====================
 Split page table lock
 =====================