Merge tag 'docs-4.19' of git://git.lwn.net/linux

Pull documentation update from Jonathan Corbet:
 "This was a moderately busy cycle for docs, with the usual collection
  of small fixes and updates.

  We also have new ktime_get_*() docs from Arnd, some kernel-doc fixes,
  a new set of Italian translations (non so se vale la pena, ma non fa
  male - speriamo bene), and some extensive early memory-management
  documentation improvements from Mike Rapoport"

* tag 'docs-4.19' of git://git.lwn.net/linux: (52 commits)
  Documentation: corrections to console/console.txt
  Documentation: add ioctl number entry for v4l2-subdev.h
  Remove gendered language from management style documentation
  scripts/kernel-doc: Escape all literal braces in regexes
  docs/mm: add description of boot time memory management
  docs/mm: memblock: add overview documentation
  docs/mm: memblock: add kernel-doc description for memblock types
  docs/mm: memblock: add kernel-doc comments for memblock_add[_node]
  docs/mm: memblock: update kernel-doc comments
  mm/memblock: add a name for memblock flags enumeration
  docs/mm: bootmem: add overview documentation
  docs/mm: bootmem: add kernel-doc description of 'struct bootmem_data'
  docs/mm: bootmem: fix kernel-doc warnings
  docs/mm: nobootmem: fixup kernel-doc comments
  mm/bootmem: drop duplicated kernel-doc comments
  Documentation: vm.txt: Adding 'nr_hugepages_mempolicy' parameter description.
  doc:it_IT: translation for kernel-hacking
  docs: Fix the reference labels in Locking.rst
  doc: tracing: Fix a typo of trace_stat
  mm: Introduce new type vm_fault_t
  ...

Documentation/admin-guide/README.rst

+.. _readme:
+
 Linux kernel release 4.x <http://kernel.org/>
 =============================================
 

Documentation/admin-guide/kernel-parameters.txt

@@ -4136,6 +4136,8 @@
 			This parameter controls whether the Speculative Store
 			Bypass optimization is used.
 
+			On x86 the options are:
+
 			on      - Unconditionally disable Speculative Store Bypass
 			off     - Unconditionally enable Speculative Store Bypass
 			auto    - Kernel detects whether the CPU model contains an
@@ -4151,12 +4153,20 @@
 			seccomp - Same as "prctl" above, but all seccomp threads
 				  will disable SSB unless they explicitly opt out.
 
-			Not specifying this option is equivalent to
-			spec_store_bypass_disable=auto.
-
 			Default mitigations:
 			X86:	If CONFIG_SECCOMP=y "seccomp", otherwise "prctl"
 
+			On powerpc the options are:
+
+			on,auto - On Power8 and Power9 insert a store-forwarding
+				  barrier on kernel entry and exit. On Power7
+				  perform a software flush on kernel entry and
+				  exit.
+			off	- No action.
+
+			Not specifying this option is equivalent to
+			spec_store_bypass_disable=auto.
+
 	spia_io_base=	[HW,MTD]
 	spia_fio_base=
 	spia_pedr=

Documentation/console/console.txt

 Console Drivers
 ===============
 
-The linux kernel has 2 general types of console drivers.  The first type is
+The Linux kernel has 2 general types of console drivers.  The first type is
 assigned by the kernel to all the virtual consoles during the boot process.
 This type will be called 'system driver', and only one system driver is allowed
 to exist. The system driver is persistent and it can never be unloaded, though
@@ -17,10 +17,11 @@ of driver occupying the consoles.) They can only take over the console that is
 occupied by the system driver. In the same token, if the modular driver is
 released by the console, the system driver will take over.
 
-Modular drivers, from the programmer's point of view, has to call:
+Modular drivers, from the programmer's point of view, have to call:
 
 	 do_take_over_console() - load and bind driver to console layer
-	 give_up_console() - unload driver, it will only work if driver is fully unbond
+	 give_up_console() - unload driver; it will only work if driver
+			     is fully unbound
 
 In newer kernels, the following are also available:
 
@@ -56,7 +57,7 @@ What do these files signify?
 	cat /sys/class/vtconsole/vtcon0/name
 	(S) VGA+
 
-	    '(S)' stands for a (S)ystem driver, ie, it cannot be directly
+	    '(S)' stands for a (S)ystem driver, i.e., it cannot be directly
 	    commanded to bind or unbind
 
 	    'VGA+' is the name of the driver
@@ -89,7 +90,7 @@ driver, make changes, recompile, reload and rebind the driver without any need
 for rebooting the kernel. For regular users who may want to switch from
 framebuffer console to VGA console and vice versa, this feature also makes
 this possible. (NOTE NOTE NOTE: Please read fbcon.txt under Documentation/fb
-for more details).
+for more details.)
 
 Notes for developers:
 =====================
@@ -110,8 +111,8 @@ In order for binding to and unbinding from the console to properly work,
 console drivers must follow these guidelines:
 
 1. All drivers, except system drivers, must call either do_register_con_driver()
-   or do_take_over_console(). do_register_con_driver() will just add the driver to
-   the console's internal list. It won't take over the
+   or do_take_over_console(). do_register_con_driver() will just add the driver
+   to the console's internal list. It won't take over the
    console. do_take_over_console(), as it name implies, will also take over (or
    bind to) the console.
 

Documentation/core-api/boot-time-mm.rst

+===========================
+Boot time memory management
+===========================
+
+Early system initialization cannot use "normal" memory management
+simply because it is not set up yet. But there is still need to
+allocate memory for various data structures, for instance for the
+physical page allocator. To address this, a specialized allocator
+called the :ref:`Boot Memory Allocator <bootmem>`, or bootmem, was
+introduced. Several years later PowerPC developers added a "Logical
+Memory Blocks" allocator, which was later adopted by other
+architectures and renamed to :ref:`memblock <memblock>`. There is also
+a compatibility layer called `nobootmem` that translates bootmem
+allocation interfaces to memblock calls.
+
+The selection of the early allocator is done using
+``CONFIG_NO_BOOTMEM`` and ``CONFIG_HAVE_MEMBLOCK`` kernel
+configuration options. These options are enabled or disabled
+statically by the architectures' Kconfig files.
+
+* Architectures that rely only on bootmem select
+  ``CONFIG_NO_BOOTMEM=n && CONFIG_HAVE_MEMBLOCK=n``.
+* The users of memblock with the nobootmem compatibility layer set
+  ``CONFIG_NO_BOOTMEM=y && CONFIG_HAVE_MEMBLOCK=y``.
+* And for those that use both memblock and bootmem the configuration
+  includes ``CONFIG_NO_BOOTMEM=n && CONFIG_HAVE_MEMBLOCK=y``.
+
+Whichever allocator is used, it is the responsibility of the
+architecture specific initialization to set it up in
+:c:func:`setup_arch` and tear it down in :c:func:`mem_init` functions.
+
+Once the early memory management is available it offers a variety of
+functions and macros for memory allocations. The allocation request
+may be directed to the first (and probably the only) node or to a
+particular node in a NUMA system. There are API variants that panic
+when an allocation fails and those that don't. And more recent and
+advanced memblock even allows controlling its own behaviour.
+
+.. _bootmem:
+
+Bootmem
+=======
+
+(mostly stolen from Mel Gorman's "Understanding the Linux Virtual
+Memory Manager" `book`_)
+
+.. _book: https://www.kernel.org/doc/gorman/
+
+.. kernel-doc:: mm/bootmem.c
+   :doc: bootmem overview
+
+.. _memblock:
+
+Memblock
+========
+
+.. kernel-doc:: mm/memblock.c
+   :doc: memblock overview
+
+
+Functions and structures
+========================
+
+Common API
+----------
+
+The functions that are described in this section are available
+regardless of what early memory manager is enabled.
+
+.. kernel-doc:: mm/nobootmem.c
+
+Bootmem specific API
+--------------------
+
+These interfaces available only with bootmem, i.e when ``CONFIG_NO_BOOTMEM=n``
+
+.. kernel-doc:: include/linux/bootmem.h
+.. kernel-doc:: mm/bootmem.c
+   :nodocs:
+
+Memblock specific API
+---------------------
+
+Here is the description of memblock data structures, functions and
+macros. Some of them are actually internal, but since they are
+documented it would be silly to omit them. Besides, reading the
+descriptions for the internal functions can help to understand what
+really happens under the hood.
+
+.. kernel-doc:: include/linux/memblock.h
+.. kernel-doc:: mm/memblock.c
+   :nodocs:

Documentation/core-api/idr.rst

@@ -76,4 +76,6 @@ Functions and structures
 ========================
 
 .. kernel-doc:: include/linux/idr.h
+   :functions:
 .. kernel-doc:: lib/idr.c
+   :functions:

Documentation/core-api/index.rst

@@ -28,6 +28,8 @@ Core utilities
    printk-formats
    circular-buffers
    gfp_mask-from-fs-io
+   timekeeping
+   boot-time-mm
 
 Interfaces for kernel debugging
 ===============================

Documentation/core-api/timekeeping.rst

+ktime accessors
+===============
+
+Device drivers can read the current time using ktime_get() and the many
+related functions declared in linux/timekeeping.h. As a rule of thumb,
+using an accessor with a shorter name is preferred over one with a longer
+name if both are equally fit for a particular use case.
+
+Basic ktime_t based interfaces
+------------------------------
+
+The recommended simplest form returns an opaque ktime_t, with variants
+that return time for different clock references:
+
+
+.. c:function:: ktime_t ktime_get( void )
+
+	CLOCK_MONOTONIC
+
+	Useful for reliable timestamps and measuring short time intervals
+	accurately. Starts at system boot time but stops during suspend.
+
+.. c:function:: ktime_t ktime_get_boottime( void )
+
+	CLOCK_BOOTTIME
+
+	Like ktime_get(), but does not stop when suspended. This can be
+	used e.g. for key expiration times that need to be synchronized
+	with other machines across a suspend operation.
+
+.. c:function:: ktime_t ktime_get_real( void )
+
+	CLOCK_REALTIME
+
+	Returns the time in relative to the UNIX epoch starting in 1970
+	using the Coordinated Universal Time (UTC), same as gettimeofday()
+	user space. This is used for all timestamps that need to
+	persist across a reboot, like inode times, but should be avoided
+	for internal uses, since it can jump backwards due to a leap
+	second update, NTP adjustment settimeofday() operation from user
+	space.
+
+.. c:function:: ktime_t ktime_get_clocktai( void )
+
+	 CLOCK_TAI
+
+	Like ktime_get_real(), but uses the International Atomic Time (TAI)
+	reference instead of UTC to avoid jumping on leap second updates.
+	This is rarely useful in the kernel.
+
+.. c:function:: ktime_t ktime_get_raw( void )
+
+	CLOCK_MONOTONIC_RAW
+
+	Like ktime_get(), but runs at the same rate as the hardware
+	clocksource without (NTP) adjustments for clock drift. This is
+	also rarely needed in the kernel.
+
+nanosecond, timespec64, and second output
+-----------------------------------------
+
+For all of the above, there are variants that return the time in a
+different format depending on what is required by the user:
+
+.. c:function:: u64 ktime_get_ns( void )
+		u64 ktime_get_boottime_ns( void )
+		u64 ktime_get_real_ns( void )
+		u64 ktime_get_tai_ns( void )
+		u64 ktime_get_raw_ns( void )
+
+	Same as the plain ktime_get functions, but returning a u64 number
+	of nanoseconds in the respective time reference, which may be
+	more convenient for some callers.
+
+.. c:function:: void ktime_get_ts64( struct timespec64 * )
+		void ktime_get_boottime_ts64( struct timespec64 * )
+		void ktime_get_real_ts64( struct timespec64 * )
+		void ktime_get_clocktai_ts64( struct timespec64 * )
+		void ktime_get_raw_ts64( struct timespec64 * )
+
+	Same above, but returns the time in a 'struct timespec64', split
+	into seconds and nanoseconds. This can avoid an extra division
+	when printing the time, or when passing it into an external
+	interface that expects a 'timespec' or 'timeval' structure.
+
+.. c:function:: time64_t ktime_get_seconds( void )
+		time64_t ktime_get_boottime_seconds( void )
+		time64_t ktime_get_real_seconds( void )
+		time64_t ktime_get_clocktai_seconds( void )
+		time64_t ktime_get_raw_seconds( void )
+
+	Return a coarse-grained version of the time as a scalar
+	time64_t. This avoids accessing the clock hardware and rounds
+	down the seconds to the full seconds of the last timer tick
+	using the respective reference.
+
+Coarse and fast_ns access
+-------------------------
+
+Some additional variants exist for more specialized cases:
+
+.. c:function:: ktime_t ktime_get_coarse_boottime( void )
+		ktime_t ktime_get_coarse_real( void )
+		ktime_t ktime_get_coarse_clocktai( void )
+		ktime_t ktime_get_coarse_raw( void )
+
+.. c:function:: void ktime_get_coarse_ts64( struct timespec64 * )
+		void ktime_get_coarse_boottime_ts64( struct timespec64 * )
+		void ktime_get_coarse_real_ts64( struct timespec64 * )
+		void ktime_get_coarse_clocktai_ts64( struct timespec64 * )
+		void ktime_get_coarse_raw_ts64( struct timespec64 * )
+
+	These are quicker than the non-coarse versions, but less accurate,
+	corresponding to CLOCK_MONONOTNIC_COARSE and CLOCK_REALTIME_COARSE
+	in user space, along with the equivalent boottime/tai/raw
+	timebase not available in user space.
+
+	The time returned here corresponds to the last timer tick, which
+	may be as much as 10ms in the past (for CONFIG_HZ=100), same as
+	reading the 'jiffies' variable.  These are only useful when called
+	in a fast path and one still expects better than second accuracy,
+	but can't easily use 'jiffies', e.g. for inode timestamps.
+	Skipping the hardware clock access saves around 100 CPU cycles
+	on most modern machines with a reliable cycle counter, but
+	up to several microseconds on older hardware with an external
+	clocksource.
+
+.. c:function:: u64 ktime_get_mono_fast_ns( void )
+		u64 ktime_get_raw_fast_ns( void )
+		u64 ktime_get_boot_fast_ns( void )
+		u64 ktime_get_real_fast_ns( void )
+
+	These variants are safe to call from any context, including from
+	a non-maskable interrupt (NMI) during a timekeeper update, and
+	while we are entering suspend with the clocksource powered down.
+	This is useful in some tracing or debugging code as well as
+	machine check reporting, but most drivers should never call them,
+	since the time is allowed to jump under certain conditions.
+
+Deprecated time interfaces
+--------------------------
+
+Older kernels used some other interfaces that are now being phased out
+but may appear in third-party drivers being ported here. In particular,
+all interfaces returning a 'struct timeval' or 'struct timespec' have
+been replaced because the tv_sec member overflows in year 2038 on 32-bit
+architectures. These are the recommended replacements:
+
+.. c:function:: void ktime_get_ts( struct timespec * )
+
+	Use ktime_get() or ktime_get_ts64() instead.
+
+.. c:function:: struct timeval do_gettimeofday( void )
+		struct timespec getnstimeofday( void )
+		struct timespec64 getnstimeofday64( void )
+		void ktime_get_real_ts( struct timespec * )
+
+	ktime_get_real_ts64() is a direct replacement, but consider using
+	monotonic time (ktime_get_ts64()) and/or a ktime_t based interface
+	(ktime_get()/ktime_get_real()).
+
+.. c:function:: struct timespec current_kernel_time( void )
+		struct timespec64 current_kernel_time64( void )
+		struct timespec get_monotonic_coarse( void )
+		struct timespec64 get_monotonic_coarse64( void )
+
+	These are replaced by ktime_get_coarse_real_ts64() and
+	ktime_get_coarse_ts64(). However, A lot of code that wants
+	coarse-grained times can use the simple 'jiffies' instead, while
+	some drivers may actually want the higher resolution accessors
+	these days.
+
+.. c:function:: struct timespec getrawmonotonic( void )
+		struct timespec64 getrawmonotonic64( void )
+		struct timespec timekeeping_clocktai( void )
+		struct timespec64 timekeeping_clocktai64( void )
+		struct timespec get_monotonic_boottime( void )
+		struct timespec64 get_monotonic_boottime64( void )
+
+	These are replaced by ktime_get_raw()/ktime_get_raw_ts64(),
+	ktime_get_clocktai()/ktime_get_clocktai_ts64() as well
+	as ktime_get_boottime()/ktime_get_boottime_ts64().
+	However, if the particular choice of clock source is not
+	important for the user, consider converting to
+	ktime_get()/ktime_get_ts64() instead for consistency.

Documentation/dev-tools/kselftest.rst

@@ -156,6 +156,11 @@ Contributing new tests (details)
    installed by the distro on the system should be the primary focus to be able
    to find regressions.
 
+ * If a test needs specific kernel config options enabled, add a config file in
+   the test directory to enable them.
+
+   e.g: tools/testing/selftests/android/ion/config
+
 Test Harness
 ============
 

Documentation/doc-guide/kernel-doc.rst

@@ -488,14 +488,19 @@ doc: *title*
     .. kernel-doc:: drivers/gpu/drm/i915/intel_audio.c
        :doc: High Definition Audio over HDMI and Display Port
 
-functions: *function* *[...]*
+functions: *[ function ...]*
   Include documentation for each *function* in *source*.
+  If no *function* if specified, the documentaion for all functions
+  and types in the *source* will be included.
 
-  Example::
+  Examples::
 
     .. kernel-doc:: lib/bitmap.c
        :functions: bitmap_parselist bitmap_parselist_user
 
+    .. kernel-doc:: lib/idr.c
+       :functions:
+
 Without options, the kernel-doc directive includes all documentation comments
 from the source file.
 

Documentation/doc-guide/parse-headers.rst

@@ -32,7 +32,7 @@ SYNOPSIS
 
 \ **parse_headers.pl**\  [<options>] <C_FILE> <OUT_FILE> [<EXCEPTIONS_FILE>]
 
-Where <options> can be: --debug, --help or --man.
+Where <options> can be: --debug, --help or --usage.
 
 
 OPTIONS
@@ -133,7 +133,7 @@ For both statements, \ **type**\  can be either one of the following:
 
 \ **symbol**\
 
- The ignore or replace statement will apply to the name of enum statements
+ The ignore or replace statement will apply to the name of enum value
  at C_FILE.
 
  For replace statements, \ **new_value**\  will automatically use :c:type:

Documentation/doc-guide/sphinx.rst

@@ -28,7 +28,7 @@ The ReST markups currently used by the Documentation/ files are meant to be
 built with ``Sphinx`` version 1.3 or upper. If you're desiring to build
 PDF outputs, it is recommended to use version 1.4.6 or upper.
 
-There's a script that checks for the Spinx requirements. Please see
+There's a script that checks for the Sphinx requirements. Please see
 :ref:`sphinx-pre-install` for further details.
 
 Most distributions are shipped with Sphinx, but its toolchain is fragile,

Documentation/driver-api/mtdnand.rst

@@ -374,7 +374,7 @@ The nand driver supports three different types of hardware ECC.
 
 -  NAND_ECC_HW8_512
 
-   Hardware ECC generator providing 6 bytes ECC per 512 byte.
+   Hardware ECC generator providing 8 bytes ECC per 512 byte.
 
 If your hardware generator has a different functionality add it at the
 appropriate place in nand_base.c
@@ -889,7 +889,7 @@ Use these constants to select the ECC algorithm::
     #define NAND_ECC_HW3_512    3
     /* Hardware ECC 6 byte ECC per 512 Byte data */
     #define NAND_ECC_HW6_512    4
-    /* Hardware ECC 6 byte ECC per 512 Byte data */
+    /* Hardware ECC 8 byte ECC per 512 Byte data */
     #define NAND_ECC_HW8_512    6
 
 

Documentation/filesystems/Locking

@@ -532,9 +532,9 @@ More details about quota locking can be found in fs/dquot.c.
 prototypes:
 	void (*open)(struct vm_area_struct*);
 	void (*close)(struct vm_area_struct*);
-	int (*fault)(struct vm_area_struct*, struct vm_fault *);
-	int (*page_mkwrite)(struct vm_area_struct *, struct vm_fault *);
-	int (*pfn_mkwrite)(struct vm_area_struct *, struct vm_fault *);
+	vm_fault_t (*fault)(struct vm_area_struct*, struct vm_fault *);
+	vm_fault_t (*page_mkwrite)(struct vm_area_struct *, struct vm_fault *);
+	vm_fault_t (*pfn_mkwrite)(struct vm_area_struct *, struct vm_fault *);
 	int (*access)(struct vm_area_struct *, unsigned long, void*, int, int);
 
 locking rules:

Documentation/filesystems/proc.txt

@@ -870,6 +870,7 @@ Committed_AS:   100056 kB
 VmallocTotal:   112216 kB
 VmallocUsed:       428 kB
 VmallocChunk:   111088 kB
+HardwareCorrupted:   0 kB
 AnonHugePages:   49152 kB
 ShmemHugePages:      0 kB
 ShmemPmdMapped:      0 kB
@@ -915,6 +916,8 @@ MemAvailable: An estimate of how much memory is available for starting new
        Dirty: Memory which is waiting to get written back to the disk
    Writeback: Memory which is actively being written back to the disk
    AnonPages: Non-file backed pages mapped into userspace page tables
+HardwareCorrupted: The amount of RAM/memory in KB, the kernel identifies as
+	      corrupted.
 AnonHugePages: Non-file backed huge pages mapped into userspace page tables
       Mapped: files which have been mmaped, such as libraries
        Shmem: Total memory used by shared memory (shmem) and tmpfs

Documentation/filesystems/relay.txt

@@ -222,7 +222,7 @@ using debugfs:
  */
 static struct dentry *create_buf_file_handler(const char *filename,
                                               struct dentry *parent,
-                                              int mode,
+                                              umode_t mode,
                                               struct rchan_buf *buf,
                                               int *is_global)
 {
@@ -375,7 +375,7 @@ would be very similar:
 static int subbuf_start(struct rchan_buf *buf,
                         void *subbuf,
 			void *prev_subbuf,
-			unsigned int prev_padding)
+			size_t prev_padding)
 {
 	if (prev_subbuf)
 		*((unsigned *)prev_subbuf) = prev_padding;

Documentation/index.rst

@@ -3,6 +3,8 @@
    You can adapt this file completely to your liking, but it should at least
    contain the root `toctree` directive.
 
+.. _linux_doc:
+
 The Linux Kernel documentation
 ==============================
 
@@ -113,29 +115,13 @@ subprojects.
 
    filesystems/ext4/index
 
-Korean translations
--------------------
-
-.. toctree::
-   :maxdepth: 1
-
-   translations/ko_KR/index
-
-Chinese translations
---------------------
+Translations
+------------
 
 .. toctree::
-   :maxdepth: 1
-
-   translations/zh_CN/index
-
-Japanese translations
----------------------
-
-.. toctree::
-   :maxdepth: 1
+   :maxdepth: 2
 
-   translations/ja_JP/index
+   translations/index
 
 Indices and tables
 ==================

Documentation/ioctl/ioctl-number.txt

@@ -274,6 +274,7 @@ Code  Seq#(hex)	Include File		Comments
 'v'	00-1F	linux/ext2_fs.h		conflict!
 'v'	00-1F	linux/fs.h		conflict!
 'v'	00-0F	linux/sonypi.h		conflict!
+'v'	00-0F	media/v4l2-subdev.h	conflict!
 'v'	C0-FF	linux/meye.h		conflict!
 'w'	all				CERN SCI driver
 'y'	00-1F				packet based user level communications

Documentation/kernel-hacking/hacking.rst

+.. _kernel_hacking_hack:
+
 ============================================
 Unreliable Guide To Hacking The Linux Kernel
 ============================================

Documentation/kernel-hacking/index.rst

+.. _kernel_hacking:
+
 =====================
 Kernel Hacking Guides
 =====================

Documentation/kernel-hacking/locking.rst

+.. _kernel_hacking_lock:
+
 ===========================
 Unreliable Guide To Locking
 ===========================
@@ -177,7 +179,7 @@ perfect world).
 
 Note that you can also use :c:func:`spin_lock_irq()` or
 :c:func:`spin_lock_irqsave()` here, which stop hardware interrupts
-as well: see `Hard IRQ Context <#hardirq-context>`__.
+as well: see `Hard IRQ Context <#hard-irq-context>`__.
 
 This works perfectly for UP as well: the spin lock vanishes, and this
 macro simply becomes :c:func:`local_bh_disable()`
@@ -228,7 +230,7 @@ The Same Softirq
 ~~~~~~~~~~~~~~~~
 
 The same softirq can run on the other CPUs: you can use a per-CPU array
-(see `Per-CPU Data <#per-cpu>`__) for better performance. If you're
+(see `Per-CPU Data <#per-cpu-data>`__) for better performance. If you're
 going so far as to use a softirq, you probably care about scalable
 performance enough to justify the extra complexity.
 

Documentation/nommu-mmap.txt

@@ -47,7 +47,7 @@ and it's also much more restricted in the latter case:
            appropriate mapping protection capabilities. Ramfs, romfs, cramfs
            and mtd might all permit this.
 
-	 - If the backing device device can't or won't permit direct sharing,
+	 - If the backing device can't or won't permit direct sharing,
            but does have the NOMMU_MAP_COPY capability, then a copy of the
            appropriate bit of the file will be read into a contiguous bit of
            memory and any extraneous space beyond the EOF will be cleared

Documentation/process/2.Process.rst

@@ -134,7 +134,7 @@ and their maintainers are:
 	4.4	Greg Kroah-Hartman	(very long-term stable kernel)
 	4.9	Greg Kroah-Hartman
 	4.14	Greg Kroah-Hartman
-	======  ======================  ===========================
+	======  ======================  ==============================
 
 The selection of a kernel for long-term support is purely a matter of a
 maintainer having the need and the time to maintain that release.  There

Documentation/process/howto.rst

@@ -85,7 +85,7 @@ linux-api@vger.kernel.org.
 Here is a list of files that are in the kernel source tree that are
 required reading:
 
-  README
+  :ref:`Documentation/admin-guide/README.rst <readme>`
     This file gives a short background on the Linux kernel and describes
     what is necessary to do to configure and build the kernel.  People
     who are new to the kernel should start here.

Documentation/process/management-style.rst

@@ -105,7 +105,7 @@ to admit that you are stupid when you haven't **yet** done the really
 stupid thing.
 
 Then, when it really does turn out to be stupid, people just roll their
-eyes and say "Oops, he did it again".
+eyes and say "Oops, not again".
 
 This preemptive admission of incompetence might also make the people who
 actually do the work also think twice about whether it's worth doing or
@@ -172,10 +172,10 @@ To solve this problem, you really only have two options:
    might even be amused.
 
 The option of being unfailingly polite really doesn't exist. Nobody will
-trust somebody who is so clearly hiding his true character.
+trust somebody who is so clearly hiding their true character.
 
 .. [#f2] Paul Simon sang "Fifty Ways to Leave Your Lover", because quite
-  frankly, "A Million Ways to Tell a Developer He Is a D*ckhead" doesn't
+  frankly, "A Million Ways to Tell a Developer They're a D*ckhead" doesn't
   scan nearly as well.  But I'm sure he thought about it.
 
 
@@ -219,15 +219,16 @@ Things will go wrong, and people want somebody to blame. Tag, you're it.
 
 It's not actually that hard to accept the blame, especially if people
 kind of realize that it wasn't **all** your fault.  Which brings us to the
-best way of taking the blame: do it for another guy. You'll feel good
-for taking the fall, he'll feel good about not getting blamed, and the
-guy who lost his whole 36GB porn-collection because of your incompetence
-will grudgingly admit that you at least didn't try to weasel out of it.
-
-Then make the developer who really screwed up (if you can find him) know
-**in_private** that he screwed up.  Not just so he can avoid it in the
-future, but so that he knows he owes you one.  And, perhaps even more
-importantly, he's also likely the person who can fix it.  Because, let's
+best way of taking the blame: do it for someone else. You'll feel good
+for taking the fall, they'll feel good about not getting blamed, and the
+person who lost their whole 36GB porn-collection because of your
+incompetence will grudgingly admit that you at least didn't try to weasel
+out of it.
+
+Then make the developer who really screwed up (if you can find them) know
+**in_private** that they screwed up.  Not just so they can avoid it in the
+future, but so that they know they owe you one.  And, perhaps even more
+importantly, they're also likely the person who can fix it.  Because, let's
 face it, it sure ain't you.
 
 Taking the blame is also why you get to be manager in the first place.

Documentation/sphinx/kerneldoc.py

@@ -47,7 +47,7 @@ class KernelDocDirective(Directive):
     optional_arguments = 4
     option_spec = {
         'doc': directives.unchanged_required,
-        'functions': directives.unchanged_required,
+        'functions': directives.unchanged,
         'export': directives.unchanged,
         'internal': directives.unchanged,
     }
@@ -75,8 +75,12 @@ class KernelDocDirective(Directive):
         elif 'doc' in self.options:
             cmd += ['-function', str(self.options.get('doc'))]
         elif 'functions' in self.options:
-            for f in str(self.options.get('functions')).split():
-                cmd += ['-function', f]
+            functions = self.options.get('functions').split()
+            if functions:
+                for f in functions:
+                    cmd += ['-function', f]
+            else:
+                cmd += ['-no-doc-sections']
 
         for pattern in export_file_patterns:
             for f in glob.glob(env.config.kerneldoc_srctree + '/' + pattern):

Documentation/sphinx/parse-headers.pl

@@ -344,7 +344,7 @@ enums and defines and create cross-references to a Sphinx book.
 
 B<parse_headers.pl> [<options>] <C_FILE> <OUT_FILE> [<EXCEPTIONS_FILE>]
 
-Where <options> can be: --debug, --help or --man.
+Where <options> can be: --debug, --help or --usage.
 
 =head1 OPTIONS
 

Documentation/sysctl/vm.txt

@@ -27,6 +27,7 @@ Currently, these files are in /proc/sys/vm:
 - dirty_bytes
 - dirty_expire_centisecs
 - dirty_ratio
+- dirtytime_expire_seconds
 - dirty_writeback_centisecs
 - drop_caches
 - extfrag_threshold
@@ -44,6 +45,7 @@ Currently, these files are in /proc/sys/vm:
 - mmap_rnd_bits
 - mmap_rnd_compat_bits
 - nr_hugepages
+- nr_hugepages_mempolicy
 - nr_overcommit_hugepages
 - nr_trim_pages         (only if CONFIG_MMU=n)
 - numa_zonelist_order
@@ -178,6 +180,18 @@ The total available memory is not equal to total system memory.
 
 ==============================================================
 
+dirtytime_expire_seconds
+
+When a lazytime inode is constantly having its pages dirtied, the inode with
+an updated timestamp will never get chance to be written out.  And, if the
+only thing that has happened on the file system is a dirtytime inode caused
+by an atime update, a worker will be scheduled to make sure that inode
+eventually gets pushed out to disk.  This tunable is used to define when dirty
+inode is old enough to be eligible for writeback by the kernel flusher threads.
+And, it is also used as the interval to wakeup dirtytime_writeback thread.
+
+==============================================================
+
 dirty_writeback_centisecs
 
 The kernel flusher threads will periodically wake up and write `old' data
@@ -519,6 +533,15 @@ See Documentation/admin-guide/mm/hugetlbpage.rst
 
 ==============================================================
 
+nr_hugepages_mempolicy
+
+Change the size of the hugepage pool at run-time on a specific
+set of NUMA nodes.
+
+See Documentation/admin-guide/mm/hugetlbpage.rst
+
+==============================================================
+
 nr_overcommit_hugepages
 
 Change the maximum size of the hugepage pool. The maximum is

Documentation/timers/timekeeping.txt

@@ -27,7 +27,7 @@ a Linux system will eventually read the clock source to determine exactly
 what time it is.
 
 Typically the clock source is a monotonic, atomic counter which will provide
-n bits which count from 0 to 2^(n-1) and then wraps around to 0 and start over.
+n bits which count from 0 to (2^n)-1 and then wraps around to 0 and start over.
 It will ideally NEVER stop ticking as long as the system is running. It
 may stop during system suspend.
 

Documentation/trace/events.rst

@@ -524,4 +524,4 @@ The following commands are supported:
   totals derived from one or more trace event format fields and/or
   event counts (hitcount).
 
-  See Documentation/trace/histogram.txt for details and examples.
+  See Documentation/trace/histogram.rst for details and examples.

Documentation/trace/ftrace.rst

@@ -329,9 +329,9 @@ of ftrace. Here is a list of some of the key files:
 	track of the time spent in those functions. The histogram
 	content can be displayed in the files:
 
-	trace_stats/function<cpu> ( function0, function1, etc).
+	trace_stat/function<cpu> ( function0, function1, etc).
 
-  trace_stats:
+  trace_stat:
 
 	A directory that holds different tracing stats.
 

Documentation/trace/index.rst

@@ -18,6 +18,7 @@ Linux Tracing Technologies
    events-nmi
    events-msr
    mmiotrace
+   histogram
    hwlat_detector
    intel_th
    stm

Documentation/trace/kprobetrace.rst

@@ -18,7 +18,7 @@ To enable this feature, build your kernel with CONFIG_KPROBE_EVENTS=y.
 Similar to the events tracer, this doesn't need to be activated via
 current_tracer. Instead of that, add probe points via
 /sys/kernel/debug/tracing/kprobe_events, and enable it via
-/sys/kernel/debug/tracing/events/kprobes/<EVENT>/enabled.
+/sys/kernel/debug/tracing/events/kprobes/<EVENT>/enable.
 
 
 Synopsis of kprobe_events
@@ -81,9 +81,9 @@ Per-probe event filtering feature allows you to set different filter on each
 probe and gives you what arguments will be shown in trace buffer. If an event
 name is specified right after 'p:' or 'r:' in kprobe_events, it adds an event
 under tracing/events/kprobes/<EVENT>, at the directory you can see 'id',
-'enabled', 'format' and 'filter'.
+'enable', 'format', 'filter' and 'trigger'.
 
-enabled:
+enable:
   You can enable/disable the probe by writing 1 or 0 on it.
 
 format:
@@ -95,6 +95,9 @@ filter:
 id:
   This shows the id of this probe event.
 
+trigger:
+  This allows to install trigger commands which are executed when the event is
+  hit (for details, see Documentation/trace/events.rst, section 6).
 
 Event Profiling
 ---------------

Documentation/trace/uprobetracer.rst

@@ -13,7 +13,7 @@ To enable this feature, build your kernel with CONFIG_UPROBE_EVENTS=y.
 Similar to the kprobe-event tracer, this doesn't need to be activated via
 current_tracer. Instead of that, add probe points via
 /sys/kernel/debug/tracing/uprobe_events, and enable it via
-/sys/kernel/debug/tracing/events/uprobes/<EVENT>/enabled.
+/sys/kernel/debug/tracing/events/uprobes/<EVENT>/enable.
 
 However unlike kprobe-event tracer, the uprobe event interface expects the
 user to calculate the offset of the probepoint in the object.

Documentation/translations/index.rst

+.. _translations:
+
+============
+Translations
+============
+
+.. toctree::
+   :maxdepth: 1
+
+   zh_CN/index
+   it_IT/index
+   ko_KR/index
+   ja_JP/index

Documentation/translations/it_IT/disclaimer-ita.rst

+:orphan:
+
+.. note::
+   This document is maintained by Federico Vaga <federico.vaga@vaga.pv.it>.
+   If you find any difference between this document and the original file or a
+   problem with the translation, please contact the maintainer of this file.
+   Following people helped to translate or review:
+   Alessia Mantegazza <amantegazza@vaga.pv.it>
+
+.. warning::
+   The purpose of this file is to be easier to read and understand for Italian
+   speakers and is not intended as a fork. So, if you have any comments or
+   updates for this file please try to update the original English file first.

Documentation/translations/it_IT/doc-guide/index.rst

+.. include:: ../disclaimer-ita.rst
+
+.. note:: Per leggere la documentazione originale in inglese:
+	  :ref:`Documentation/doc-guide/index.rst <doc_guide>`
+
+.. _it_doc_guide:
+
+==========================================
+Come scrivere la documentazione del kernel
+==========================================
+
+.. toctree::
+   :maxdepth: 1
+
+   sphinx.rst
+   kernel-doc.rst
+   parse-headers.rst
+
+.. only::  subproject and html
+
+   Indices
+   =======
+
+   * :ref:`genindex`

Documentation/translations/it_IT/doc-guide/parse-headers.rst

+.. include:: ../disclaimer-ita.rst
+
+.. note:: Per leggere la documentazione originale in inglese:
+	  :ref:`Documentation/doc-guide/index.rst <doc_guide>`
+
+=========================================
+Includere gli i file di intestazione uAPI
+=========================================
+
+Qualche volta è utile includere dei file di intestazione e degli esempi di codice C
+al fine di descrivere l'API per lo spazio utente e per generare dei riferimenti
+fra il codice e la documentazione. Aggiungere i riferimenti ai file dell'API
+dello spazio utente ha ulteriori vantaggi: Sphinx genererà dei messaggi
+d'avviso se un simbolo non viene trovato nella documentazione. Questo permette
+di mantenere allineate la documentazione della uAPI (API spazio utente)
+con le modifiche del kernel.
+Il programma :ref:`parse_headers.pl <it_parse_headers>` genera questi riferimenti.
+Esso dev'essere invocato attraverso un Makefile, mentre si genera la
+documentazione. Per avere un esempio su come utilizzarlo all'interno del kernel
+consultate ``Documentation/media/Makefile``.
+
+.. _it_parse_headers:
+
+parse_headers.pl
+^^^^^^^^^^^^^^^^
+
+NOME
+****
+
+
+parse_headers.pl - analizza i file C al fine di identificare funzioni,
+strutture, enumerati e definizioni, e creare riferimenti per Sphinx
+
+SINTASSI
+********
+
+
+\ **parse_headers.pl**\  [<options>] <C_FILE> <OUT_FILE> [<EXCEPTIONS_FILE>]
+
+Dove <options> può essere: --debug, --usage o --help.
+
+
+OPZIONI
+*******
+
+
+
+\ **--debug**\
+
+ Lo script viene messo in modalità verbosa, utile per il debugging.
+
+
+\ **--usage**\
+
+ Mostra un messaggio d'aiuto breve e termina.
+
+
+\ **--help**\
+
+ Mostra un messaggio d'aiuto dettagliato e termina.
+
+
+DESCRIZIONE
+***********
+
+Converte un file d'intestazione o un file sorgente C (C_FILE) in un testo
+ReStructuredText incluso mediante il blocco ..parsed-literal
+con riferimenti alla documentazione che descrive l'API. Opzionalmente,
+il programma accetta anche un altro file (EXCEPTIONS_FILE) che
+descrive quali elementi debbano essere ignorati o il cui riferimento
+deve puntare ad elemento diverso dal predefinito.
+
+Il file generato sarà disponibile in (OUT_FILE).
+
+Il programma è capace di identificare *define*, funzioni, strutture,
+tipi di dato, enumerati e valori di enumerati, e di creare i riferimenti
+per ognuno di loro. Inoltre, esso è capace di distinguere le #define
+utilizzate per specificare i comandi ioctl di Linux.
+
+Il file EXCEPTIONS_FILE contiene due tipi di dichiarazioni:
+\ **ignore**\  o \ **replace**\ .
+
+La sintassi per ignore è:
+
+ignore \ **tipo**\  \ **nome**\
+
+La dichiarazione \ **ignore**\  significa che non verrà generato alcun
+riferimento per il simbolo \ **name**\  di tipo \ **tipo**\ .
+
+
+La sintassi per replace è:
+
+replace \ **tipo**\  \ **nome**\  \ **nuovo_valore**\
+
+La dichiarazione \ **replace**\  significa che verrà generato un
+riferimento per il simbolo \ **name**\ di tipo \ **tipo**\ , ma, invece
+di utilizzare il valore predefinito, verrà utilizzato il valore
+\ **nuovo_valore**\ .
+
+Per entrambe le dichiarazioni, il \ **tipo**\  può essere uno dei seguenti:
+
+
+\ **ioctl**\
+
+ La dichiarazione ignore o replace verrà applicata su definizioni di ioctl
+ come la seguente:
+
+ #define	VIDIOC_DBG_S_REGISTER 	 _IOW('V', 79, struct v4l2_dbg_register)
+
+
+
+\ **define**\
+
+ La dichiarazione ignore o replace verrà applicata su una qualsiasi #define
+ trovata in C_FILE.
+
+
+
+\ **typedef**\
+
+ La dichiarazione ignore o replace verrà applicata ad una dichiarazione typedef
+ in C_FILE.
+
+
+
+\ **struct**\
+
+ La dichiarazione ignore o replace verrà applicata ai nomi di strutture
+ in C_FILE.
+
+
+
+\ **enum**\
+
+ La dichiarazione ignore o replace verrà applicata ai nomi di enumerati
+ in C_FILE.
+
+
+
+\ **symbol**\
+
+ La dichiarazione ignore o replace verrà applicata ai nomi di valori di
+ enumerati in C_FILE.
+
+ Per le dichiarazioni di tipo replace, il campo \ **new_value**\  utilizzerà
+ automaticamente i riferimenti :c:type: per \ **typedef**\ , \ **enum**\  e
+ \ **struct**\. Invece, utilizzerà :ref: per \ **ioctl**\ , \ **define**\  e
+ \ **symbol**\. Il tipo di riferimento può essere definito esplicitamente
+ nella dichiarazione stessa.
+
+
+ESEMPI
+******
+
+
+ignore define _VIDEODEV2_H
+
+
+Ignora una definizione #define _VIDEODEV2_H nel file C_FILE.
+
+ignore symbol PRIVATE
+
+
+In un enumerato come il seguente:
+
+enum foo { BAR1, BAR2, PRIVATE };
+
+Non genererà alcun riferimento per \ **PRIVATE**\ .
+
+replace symbol BAR1 :c:type:\`foo\`
+replace symbol BAR2 :c:type:\`foo\`
+
+
+In un enumerato come il seguente:
+
+enum foo { BAR1, BAR2, PRIVATE };
+
+Genererà un riferimento ai valori BAR1 e BAR2 dal simbolo foo nel dominio C.
+
+
+BUGS
+****
+
+Riferire ogni malfunzionamento a Mauro Carvalho Chehab <mchehab@s-opensource.com>
+
+
+COPYRIGHT
+*********
+
+
+Copyright (c) 2016 by Mauro Carvalho Chehab <mchehab@s-opensource.com>.
+
+Licenza GPLv2: GNU GPL version 2 <http://gnu.org/licenses/gpl.html>.
+
+Questo è software libero: siete liberi di cambiarlo e ridistribuirlo.
+Non c'è alcuna garanzia, nei limiti permessi dalla legge.

Documentation/translations/it_IT/index.rst

+.. _it_linux_doc:
+
+===================
+Traduzione italiana
+===================
+
+L'obiettivo di questa traduzione è di rendere più facile la lettura e
+la comprensione per chi preferisce leggere in lingua italiana.
+Tenete presente che la documentazione di riferimento rimane comunque
+quella in lingua inglese: :ref:`linux_doc`
+
+Questa traduzione cerca di essere il più fedele possibile all'originale ma
+è ovvio che alcune frasi vadano trasformate: non aspettatevi una traduzione
+letterale. Quando possibile, si eviteranno gli inglesismi ed al loro posto
+verranno utilizzate le corrispettive parole italiane.
+
+Se notate che la traduzione non è più aggiornata potete contattare
+direttamente il manutentore della traduzione italiana.
+
+Se notate che la documentazione contiene errori o dimenticanze, allora
+verificate la documentazione di riferimento in lingua inglese. Se il problema
+è presente anche nella documentazione di riferimento, contattate il suo
+manutentore. Se avete problemi a scrivere in inglese, potete comunque
+riportare il problema al manutentore della traduzione italiana.
+
+Manutentore della traduzione italiana: Federico Vaga <federico.vaga@vaga.pv.it>
+
+La documentazione del kernel Linux
+==================================
+
+Questo è il livello principale della documentazione del kernel in
+lingua italiana. La traduzione è incompleta, noterete degli avvisi
+che vi segnaleranno la mancanza di una traduzione o di un gruppo di
+traduzioni.
+
+Più in generale, la documentazione, come il kernel stesso, sono in
+costante sviluppo; particolarmente vero in quanto stiamo lavorando
+alla riorganizzazione della documentazione in modo più coerente.
+I miglioramenti alla documentazione sono sempre i benvenuti; per cui,
+se vuoi aiutare, iscriviti alla lista di discussione linux-doc presso
+vger.kernel.org.
+
+Documentazione sulla licenza dei sorgenti
+-----------------------------------------
+
+I seguenti documenti descrivono la licenza usata nei sorgenti del kernel Linux
+(GPLv2), come licenziare i singoli file; inoltre troverete i riferimenti al
+testo integrale della licenza.
+
+.. warning::
+
+    TODO ancora da tradurre
+
+Documentazione per gli utenti
+-----------------------------
+
+I seguenti manuali sono scritti per gli *utenti* del kernel - ovvero,
+coloro che cercano di farlo funzionare in modo ottimale su un dato sistema
+
+.. warning::
+
+    TODO ancora da tradurre
+
+Documentazione per gli sviluppatori di applicazioni
+---------------------------------------------------
+
+Il manuale delle API verso lo spazio utente è una collezione di documenti
+che descrivono le interfacce del kernel viste dagli sviluppatori
+di applicazioni.
+
+.. warning::
+
+    TODO ancora da tradurre
+
+
+Introduzione allo sviluppo del kernel
+-------------------------------------
+
+Questi manuali contengono informazioni su come contribuire allo sviluppo
+del kernel.
+Attorno al kernel Linux gira una comunità molto grande con migliaia di
+sviluppatori che contribuiscono ogni anno. Come in ogni grande comunità,
+sapere come le cose vengono fatte renderà il processo di integrazione delle
+vostre modifiche molto più semplice
+
+.. toctree::
+   :maxdepth: 2
+
+   doc-guide/index
+   kernel-hacking/index
+
+.. warning::
+
+    TODO ancora da tradurre
+
+Documentazione della API del kernel
+-----------------------------------
+
+Questi manuali forniscono dettagli su come funzionano i sottosistemi del
+kernel dal punto di vista degli sviluppatori del kernel. Molte delle
+informazioni contenute in questi manuali sono prese direttamente dai
+file sorgenti, informazioni aggiuntive vengono aggiunte solo se necessarie
+(o almeno ci proviamo — probabilmente *non* tutto quello che è davvero
+necessario).
+
+.. warning::
+
+    TODO ancora da tradurre
+
+Documentazione specifica per architettura
+-----------------------------------------
+
+Questi manuali forniscono dettagli di programmazione per le diverse
+implementazioni d'architettura.
+
+.. warning::
+
+    TODO ancora da tradurre

Documentation/translations/it_IT/kernel-hacking/index.rst

+.. include:: ../disclaimer-ita.rst
+
+:Original: :ref:`Documentation/kernel-hacking/index.rst <kernel_hacking>`
+:Translator: Federico Vaga <federico.vaga@vaga.pv.it>
+
+.. _it_kernel_hacking:
+
+============================
+Guida all'hacking del kernel
+============================
+
+.. toctree::
+   :maxdepth: 2
+
+   hacking
+   locking

Documentation/translations/zh_CN/oops-tracing.txt

-Chinese translated version of Documentation/admin-guide/oops-tracing.rst
+Chinese translated version of Documentation/admin-guide/bug-hunting.rst
 
 If you have any comment or update to the content, please contact the
 original document maintainer directly.  However, if you have a problem
@@ -8,7 +8,7 @@ or if there is a problem with the translation.
 
 Chinese maintainer: Dave Young <hidave.darkstar@gmail.com>
 ---------------------------------------------------------------------
-Documentation/admin-guide/oops-tracing.rst 的中文翻译
+Documentation/admin-guide/bug-hunting.rst 的中文翻译
 
 如果想评论或更新本文的内容，请直接联系原文档的维护者。如果你使用英文
 交流有困难的话，也可以向中文版维护者求助。如果本翻译更新不及时或者翻

MAINTAINERS

@@ -4406,6 +4406,12 @@ X:	Documentation/spi
 X:	Documentation/media
 T:	git git://git.lwn.net/linux.git docs-next
 
+DOCUMENTATION/ITALIAN
+M:	Federico Vaga <federico.vaga@vaga.pv.it>
+L:	linux-doc@vger.kernel.org
+S:	Maintained
+F:	Documentation/translations/it_IT
+
 DONGWOON DW9714 LENS VOICE COIL DRIVER
 M:	Sakari Ailus <sakari.ailus@linux.intel.com>
 L:	linux-media@vger.kernel.org
@@ -7034,7 +7040,7 @@ M:	Guenter Roeck <linux@roeck-us.net>
 L:	linux-hwmon@vger.kernel.org
 S:	Maintained
 F:	Documentation/hwmon/ina209
-F:	Documentation/devicetree/bindings/i2c/ina209.txt
+F:	Documentation/devicetree/bindings/hwmon/ina2xx.txt
 F:	drivers/hwmon/ina209.c
 
 INA2XX HARDWARE MONITOR DRIVER

include/linux/bootmem.h

@@ -27,9 +27,20 @@ extern unsigned long max_pfn;
 extern unsigned long long max_possible_pfn;
 
 #ifndef CONFIG_NO_BOOTMEM
-/*
- * node_bootmem_map is a map pointer - the bits represent all physical 
- * memory pages (including holes) on the node.
+/**
+ * struct bootmem_data - per-node information used by the bootmem allocator
+ * @node_min_pfn: the starting physical address of the node's memory
+ * @node_low_pfn: the end physical address of the directly addressable memory
+ * @node_bootmem_map: is a bitmap pointer - the bits represent all physical
+ *		      memory pages (including holes) on the node.
+ * @last_end_off: the offset within the page of the end of the last allocation;
+ *                if 0, the page used is full
+ * @hint_idx: the PFN of the page used with the last allocation;
+ *            together with using this with the @last_end_offset field,
+ *            a test can be made to see if allocations can be merged
+ *            with the page used for the last allocation rather than
+ *            using up a full new page.
+ * @list: list entry in the linked list ordered by the memory addresses
  */
 typedef struct bootmem_data {
 	unsigned long node_min_pfn;

include/linux/gpio.h

@@ -14,7 +14,7 @@
 
 #include <linux/errno.h>
 
-/* see Documentation/gpio/gpio-legacy.txt */
+/* see Documentation/driver-api/gpio/legacy.rst */
 
 /* make these flag values available regardless of GPIO kconfig options */
 #define GPIOF_DIR_OUT	(0 << 0)

include/linux/memblock.h

@@ -20,31 +20,60 @@
 #define INIT_MEMBLOCK_REGIONS	128
 #define INIT_PHYSMEM_REGIONS	4
 
-/* Definition of memblock flags. */
-enum {
+/**
+ * enum memblock_flags - definition of memory region attributes
+ * @MEMBLOCK_NONE: no special request
+ * @MEMBLOCK_HOTPLUG: hotpluggable region
+ * @MEMBLOCK_MIRROR: mirrored region
+ * @MEMBLOCK_NOMAP: don't add to kernel direct mapping
+ */
+enum memblock_flags {
 	MEMBLOCK_NONE		= 0x0,	/* No special request */
 	MEMBLOCK_HOTPLUG	= 0x1,	/* hotpluggable region */
 	MEMBLOCK_MIRROR		= 0x2,	/* mirrored region */
 	MEMBLOCK_NOMAP		= 0x4,	/* don't add to kernel direct mapping */
 };
 
+/**
+ * struct memblock_region - represents a memory region
+ * @base: physical address of the region
+ * @size: size of the region
+ * @flags: memory region attributes
+ * @nid: NUMA node id
+ */
 struct memblock_region {
 	phys_addr_t base;
 	phys_addr_t size;
-	unsigned long flags;
+	enum memblock_flags flags;
 #ifdef CONFIG_HAVE_MEMBLOCK_NODE_MAP
 	int nid;
 #endif
 };
 
+/**
+ * struct memblock_type - collection of memory regions of certain type
+ * @cnt: number of regions
+ * @max: size of the allocated array
+ * @total_size: size of all regions
+ * @regions: array of regions
+ * @name: the memory type symbolic name
+ */
 struct memblock_type {
-	unsigned long cnt;	/* number of regions */
-	unsigned long max;	/* size of the allocated array */
-	phys_addr_t total_size;	/* size of all regions */
+	unsigned long cnt;
+	unsigned long max;
+	phys_addr_t total_size;
 	struct memblock_region *regions;
 	char *name;
 };
 
+/**
+ * struct memblock - memblock allocator metadata
+ * @bottom_up: is bottom up direction?
+ * @current_limit: physical address of the current allocation limit
+ * @memory: usabe memory regions
+ * @reserved: reserved memory regions
+ * @physmem: all physical memory
+ */
 struct memblock {
 	bool bottom_up;  /* is bottom up direction? */
 	phys_addr_t current_limit;
@@ -72,7 +101,7 @@ void memblock_discard(void);
 
 phys_addr_t memblock_find_in_range_node(phys_addr_t size, phys_addr_t align,
 					phys_addr_t start, phys_addr_t end,
-					int nid, ulong flags);
+					int nid, enum memblock_flags flags);
 phys_addr_t memblock_find_in_range(phys_addr_t start, phys_addr_t end,
 				   phys_addr_t size, phys_addr_t align);
 void memblock_allow_resize(void);
@@ -89,19 +118,19 @@ int memblock_clear_hotplug(phys_addr_t base, phys_addr_t size);
 int memblock_mark_mirror(phys_addr_t base, phys_addr_t size);
 int memblock_mark_nomap(phys_addr_t base, phys_addr_t size);
 int memblock_clear_nomap(phys_addr_t base, phys_addr_t size);
-ulong choose_memblock_flags(void);
+enum memblock_flags choose_memblock_flags(void);
 
 /* Low level functions */
 int memblock_add_range(struct memblock_type *type,
 		       phys_addr_t base, phys_addr_t size,
-		       int nid, unsigned long flags);
+		       int nid, enum memblock_flags flags);
 
-void __next_mem_range(u64 *idx, int nid, ulong flags,
+void __next_mem_range(u64 *idx, int nid, enum memblock_flags flags,
 		      struct memblock_type *type_a,
 		      struct memblock_type *type_b, phys_addr_t *out_start,
 		      phys_addr_t *out_end, int *out_nid);
 
-void __next_mem_range_rev(u64 *idx, int nid, ulong flags,
+void __next_mem_range_rev(u64 *idx, int nid, enum memblock_flags flags,
 			  struct memblock_type *type_a,
 			  struct memblock_type *type_b, phys_addr_t *out_start,
 			  phys_addr_t *out_end, int *out_nid);
@@ -239,7 +268,6 @@ void __next_mem_pfn_range(int *idx, int nid, unsigned long *out_start_pfn,
 /**
  * for_each_resv_unavail_range - iterate through reserved and unavailable memory
  * @i: u64 used as loop variable
- * @flags: pick from blocks based on memory attributes
  * @p_start: ptr to phys_addr_t for start address of the range, can be %NULL
  * @p_end: ptr to phys_addr_t for end address of the range, can be %NULL
  *
@@ -253,13 +281,13 @@ void __next_mem_pfn_range(int *idx, int nid, unsigned long *out_start_pfn,
 			   NUMA_NO_NODE, MEMBLOCK_NONE, p_start, p_end, NULL)
 
 static inline void memblock_set_region_flags(struct memblock_region *r,
-					     unsigned long flags)
+					     enum memblock_flags flags)
 {
 	r->flags |= flags;
 }
 
 static inline void memblock_clear_region_flags(struct memblock_region *r,
-					       unsigned long flags)
+					       enum memblock_flags flags)
 {
 	r->flags &= ~flags;
 }
@@ -317,10 +345,10 @@ static inline bool memblock_bottom_up(void)
 
 phys_addr_t __init memblock_alloc_range(phys_addr_t size, phys_addr_t align,
 					phys_addr_t start, phys_addr_t end,
-					ulong flags);
+					enum memblock_flags flags);
 phys_addr_t memblock_alloc_base_nid(phys_addr_t size,
 					phys_addr_t align, phys_addr_t max_addr,
-					int nid, ulong flags);
+					int nid, enum memblock_flags flags);
 phys_addr_t memblock_alloc_base(phys_addr_t size, phys_addr_t align,
 				phys_addr_t max_addr);
 phys_addr_t __memblock_alloc_base(phys_addr_t size, phys_addr_t align,
@@ -367,8 +395,10 @@ phys_addr_t memblock_get_current_limit(void);
  */
 
 /**
- * memblock_region_memory_base_pfn - Return the lowest pfn intersecting with the memory region
+ * memblock_region_memory_base_pfn - get the lowest pfn of the memory region
  * @reg: memblock_region structure
+ *
+ * Return: the lowest pfn intersecting with the memory region
  */
 static inline unsigned long memblock_region_memory_base_pfn(const struct memblock_region *reg)
 {
@@ -376,8 +406,10 @@ static inline unsigned long memblock_region_memory_base_pfn(const struct membloc
 }
 
 /**
- * memblock_region_memory_end_pfn - Return the end_pfn this region
+ * memblock_region_memory_end_pfn - get the end pfn of the memory region
  * @reg: memblock_region structure
+ *
+ * Return: the end_pfn of the reserved region
  */
 static inline unsigned long memblock_region_memory_end_pfn(const struct memblock_region *reg)
 {
@@ -385,8 +417,10 @@ static inline unsigned long memblock_region_memory_end_pfn(const struct memblock
 }
 
 /**
- * memblock_region_reserved_base_pfn - Return the lowest pfn intersecting with the reserved region
+ * memblock_region_reserved_base_pfn - get the lowest pfn of the reserved region
  * @reg: memblock_region structure
+ *
+ * Return: the lowest pfn intersecting with the reserved region
  */
 static inline unsigned long memblock_region_reserved_base_pfn(const struct memblock_region *reg)
 {
@@ -394,8 +428,10 @@ static inline unsigned long memblock_region_reserved_base_pfn(const struct membl
 }
 
 /**
- * memblock_region_reserved_end_pfn - Return the end_pfn this region
+ * memblock_region_reserved_end_pfn - get the end pfn of the reserved region
  * @reg: memblock_region structure
+ *
+ * Return: the end_pfn of the reserved region
  */
 static inline unsigned long memblock_region_reserved_end_pfn(const struct memblock_region *reg)
 {

include/linux/timekeeping.h

@@ -20,6 +20,21 @@ extern int do_settimeofday64(const struct timespec64 *ts);
 extern int do_sys_settimeofday64(const struct timespec64 *tv,
 				 const struct timezone *tz);
 
+/*
+ * ktime_get() family: read the current time in a multitude of ways,
+ *
+ * The default time reference is CLOCK_MONOTONIC, starting at
+ * boot time but not counting the time spent in suspend.
+ * For other references, use the functions with "real", "clocktai",
+ * "boottime" and "raw" suffixes.
+ *
+ * To get the time in a different format, use the ones wit
+ * "ns", "ts64" and "seconds" suffix.
+ *
+ * See Documentation/core-api/timekeeping.rst for more details.
+ */
+
+
 /*
  * timespec64 based interfaces
  */