Docs/{ABI,admin-guide}/damon: update for fixed virtual address ranges monitoring

This commit documents the user space support of the newly added monitoring
operations set for fixed virtual address ranges monitoring, namely
'fvaddr', on the ABI and usage documents for DAMON.

Link: https://lkml.kernel.org/r/20220426231750.48822-4-sj@kernel.orgSigned-off-by: NSeongJae Park <sj@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>

Documentation/ABI/testing/sysfs-kernel-mm-damon

@@ -50,12 +50,14 @@ What:		/sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/operations
 Date:		Mar 2022
 Contact:	SeongJae Park <sj@kernel.org>
 Description:	Writing a keyword for a monitoring operations set ('vaddr' for
-		virtual address spaces monitoring, and 'paddr' for the physical
-		address space monitoring) to this file makes the context to use
-		the operations set.  Reading the file returns the keyword for
-		the operations set the context is set to use.  Note that only
-		the operations sets that listed in 'avail_operations' file are
-		valid inputs.
+		virtual address spaces monitoring, 'fvaddr' for fixed virtual
+		address ranges monitoring, and 'paddr' for the physical address
+		space monitoring) to this file makes the context to use the
+		operations set.  Reading the file returns the keyword for the
+		operations set the context is set to use.
+
+		Note that only the operations sets that listed in
+		'avail_operations' file are valid inputs.
 
 What:		/sys/kernel/mm/damon/admin/kdamonds/<K>/contexts/<C>/monitoring_attrs/intervals/sample_us
 Date:		Mar 2022

Documentation/admin-guide/mm/damon/usage.rst

@@ -154,8 +154,13 @@ available monitoring operations set on the currently running kernel by reading
 list some or all of below keywords.
 
  - vaddr: Monitor virtual address spaces of specific processes
+ - fvaddr: Monitor fixed virtual address ranges
  - paddr: Monitor the physical address space of the system
 
+Please refer to :ref:`regions sysfs directory <sysfs_regions>` for detailed
+differences between the operations sets in terms of the monitoring target
+regions.
+
 You can set and get what type of monitoring operations DAMON will use for the
 context by writing one of the keywords listed in ``avail_operations`` file and
 reading from the ``operations`` file.
@@ -198,6 +203,8 @@ If you wrote ``vaddr`` to the ``contexts/<N>/operations``, each target should
 be a process.  You can specify the process to DAMON by writing the pid of the
 process to the ``pid_target`` file.
 
+.. _sysfs_regions:
+
 targets/<N>/regions
 -------------------
 
@@ -208,9 +215,10 @@ can be covered.  However, users could want to set the initial monitoring region
 to specific address ranges.
 
 In contrast, DAMON do not automatically sets and updates the monitoring target
-regions when ``paddr`` monitoring operations set is being used (``paddr`` is
-written to the ``contexts/<N>/operations``).  Therefore, users should set the
-monitoring target regions by themselves in the case.
+regions when ``fvaddr`` or ``paddr`` monitoring operations sets are being used
+(``fvaddr`` or ``paddr`` have written to the ``contexts/<N>/operations``).
+Therefore, users should set the monitoring target regions by themselves in the
+cases.
 
 For such cases, users can explicitly set the initial monitoring target regions
 as they want, by writing proper values to the files under this directory.