Merge tag 'docs-5.16' of git://git.lwn.net/linux

Pull documentation updates from Jonathan Corbet:
 "This is a relatively unexciting cycle for documentation.

   - Some small scripts/kerneldoc fixes

   - More Chinese translation work, but at a much reduced rate.

   - The tip-tree maintainer's handbook

  ...plus the usual array of build fixes, typo fixes, etc"

* tag 'docs-5.16' of git://git.lwn.net/linux: (53 commits)
  kernel-doc: support DECLARE_PHY_INTERFACE_MASK()
  docs/zh_CN: add core-api xarray translation
  docs/zh_CN: add core-api assoc_array translation
  speakup: Fix typo in documentation "boo" -> "boot"
  docs: submitting-patches: make section about the Link: tag more explicit
  docs: deprecated.rst: Clarify open-coded arithmetic with literals
  scripts: documentation-file-ref-check: fix bpf selftests path
  scripts: documentation-file-ref-check: ignore hidden files
  coding-style.rst: trivial: fix location of driver model macros
  docs: f2fs: fix text alignment
  docs/zh_CN add PCI pci.rst translation
  docs/zh_CN add PCI index.rst translation
  docs: translations: zh_CN: memory-hotplug.rst: fix a typo
  docs: translations: zn_CN: irq-affinity.rst: add a missing extension
  block: add documentation for inflight
  scripts: kernel-doc: Ignore __alloc_size() attribute
  docs: pdfdocs: Adjust \headheight for fancyhdr
  docs: UML: user_mode_linux_howto_v2 edits
  docs: use the lore redirector everywhere
  docs: proc.rst: mountinfo: align columns
  ...

54 files changed, 3866 insertions, 173 deletions

diff --git a/Documentation/ABI/testing/sysfs-block b/Documentation/ABI/testing/sysfs-block
index a0ed87386639..b16b0c45a272 100644
--- a/Documentation/ABI/testing/sysfs-block
+++ b/Documentation/ABI/testing/sysfs-block
@@ -28,6 +28,22 @@ Description:
 		For more details refer Documentation/admin-guide/iostats.rst
 
 
+What:		/sys/block/<disk>/inflight
+Date:		October 2009
+Contact:	Jens Axboe <axboe@kernel.dk>, Nikanth Karthikesan <knikanth@suse.de>
+Description:
+		Reports the number of I/O requests currently in progress
+		(pending / in flight) in a device driver. This can be less
+		than the number of requests queued in the block device queue.
+		The report contains 2 fields: one for read requests
+		and one for write requests.
+		The value type is unsigned int.
+		Cf. Documentation/block/stat.rst which contains a single value for
+		requests in flight.
+		This is related to nr_requests in Documentation/block/queue-sysfs.rst
+		and for SCSI device also its queue_depth.
+
+
 What:		/sys/block/<disk>/diskseq
 Date:		February 2021
 Contact:	Matteo Croce <mcroce@microsoft.com>
diff --git a/Documentation/ABI/testing/sysfs-driver-xen-blkback b/Documentation/ABI/testing/sysfs-driver-xen-blkback
index ac2947b98950..a74dfe52dd76 100644
--- a/Documentation/ABI/testing/sysfs-driver-xen-blkback
+++ b/Documentation/ABI/testing/sysfs-driver-xen-blkback
@@ -29,7 +29,7 @@ Description:
 What:           /sys/module/xen_blkback/parameters/buffer_squeeze_duration_ms
 Date:           December 2019
 KernelVersion:  5.6
-Contact:        SeongJae Park <sjpark@amazon.de>
+Contact:        SeongJae Park <sj@kernel.org>
 Description:
                 When memory pressure is reported to blkback this option
                 controls the duration in milliseconds that blkback will not
@@ -39,7 +39,7 @@ Description:
 What:           /sys/module/xen_blkback/parameters/feature_persistent
 Date:           September 2020
 KernelVersion:  5.10
-Contact:        SeongJae Park <sjpark@amazon.de>
+Contact:        SeongJae Park <sj@kernel.org>
 Description:
                 Whether to enable the persistent grants feature or not.  Note
                 that this option only takes effect on newly created backends.
diff --git a/Documentation/ABI/testing/sysfs-driver-xen-blkfront b/Documentation/ABI/testing/sysfs-driver-xen-blkfront
index 28008905615f..61fd173fabfe 100644
--- a/Documentation/ABI/testing/sysfs-driver-xen-blkfront
+++ b/Documentation/ABI/testing/sysfs-driver-xen-blkfront
@@ -12,7 +12,7 @@ Description:
 What:           /sys/module/xen_blkfront/parameters/feature_persistent
 Date:           September 2020
 KernelVersion:  5.10
-Contact:        SeongJae Park <sjpark@amazon.de>
+Contact:        SeongJae Park <sj@kernel.org>
 Description:
                 Whether to enable the persistent grants feature or not.  Note
                 that this option only takes effect on newly created frontends.
diff --git a/Documentation/admin-guide/mm/pagemap.rst b/Documentation/admin-guide/mm/pagemap.rst
index fb578fbbb76c..4581527c07ae 100644
--- a/Documentation/admin-guide/mm/pagemap.rst
+++ b/Documentation/admin-guide/mm/pagemap.rst
@@ -196,6 +196,28 @@ you can go through every map in the process, find the PFNs, look those up
 in kpagecount, and tally up the number of pages that are only referenced
 once.
 
+Exceptions for Shared Memory
+============================
+
+Page table entries for shared pages are cleared when the pages are zapped or
+swapped out. This makes swapped out pages indistinguishable from never-allocated
+ones.
+
+In kernel space, the swap location can still be retrieved from the page cache.
+However, values stored only on the normal PTE get lost irretrievably when the
+page is swapped out (i.e. SOFT_DIRTY).
+
+In user space, whether the page is present, swapped or none can be deduced with
+the help of lseek and/or mincore system calls.
+
+lseek() can differentiate between accessed pages (present or swapped out) and
+holes (none/non-allocated) by specifying the SEEK_DATA flag on the file where
+the pages are backed. For anonymous shared pages, the file can be found in
+``/proc/pid/map_files/``.
+
+mincore() can differentiate between pages in memory (present, including swap
+cache) and out of memory (swapped out or none/non-allocated).
+
 Other notes
 ===========
 
diff --git a/Documentation/admin-guide/spkguide.txt b/Documentation/admin-guide/spkguide.txt
index 977ab3f5a0a8..1265c1eab31c 100644
--- a/Documentation/admin-guide/spkguide.txt
+++ b/Documentation/admin-guide/spkguide.txt
@@ -543,7 +543,7 @@ As mentioned earlier, Speakup can either be completely compiled into the
 kernel, with the exception of the help module, or it can be compiled as
 a series of modules.   When compiled as modules, Speakup will only be
 able to speak some of the bootup messages if your system administrator
-has configured the system to load the modules at boo time. The modules
+has configured the system to load the modules at boot time. The modules
 can  be loaded after the file systems have been checked and mounted, or
 from an initrd.  There is a third possibility.  Speakup can be compiled
 with some components built into the kernel, and others as modules.  As
diff --git a/Documentation/arm/marvell.rst b/Documentation/arm/marvell.rst
index 56bb592dbd0c..8323c79d321b 100644
--- a/Documentation/arm/marvell.rst
+++ b/Documentation/arm/marvell.rst
@@ -21,6 +21,7 @@ Orion family
                - Datasheet: https://web.archive.org/web/20210124231420/http://csclub.uwaterloo.ca/~board/ts7800/MV88F5182-datasheet.pdf
                - Programmer's User Guide: https://web.archive.org/web/20210124231536/http://csclub.uwaterloo.ca/~board/ts7800/MV88F5182-opensource-manual.pdf
                - User Manual: https://web.archive.org/web/20210124231631/http://csclub.uwaterloo.ca/~board/ts7800/MV88F5182-usermanual.pdf
+               - Functional Errata: https://web.archive.org/web/20210704165540/https://www.digriz.org.uk/ts78xx/88F5182_Functional_Errata.pdf
         - 88F5281
 
                - Datasheet: https://web.archive.org/web/20131028144728/http://www.ocmodshop.com/images/reviews/networking/qnap_ts409u/marvel_88f5281_data_sheet.pdf
@@ -212,6 +213,7 @@ EBU Armada family ARMv8
 	arch/arm64/boot/dts/marvell/armada-37*
 
   Armada 7K Flavors:
+	  - 88F6040 (AP806 Quad 600 MHz + one CP110)
 	  - 88F7020 (AP806 Dual + one CP110)
 	  - 88F7040 (AP806 Quad + one CP110)
 
@@ -243,6 +245,23 @@ EBU Armada family ARMv8
   Device tree files:
 	arch/arm64/boot/dts/marvell/armada-80*
 
+  Octeon TX2 CN913x Flavors:
+	- CN9130 (AP807 Quad + one internal CP115)
+	- CN9131 (AP807 Quad + one internal CP115 + one external CP115 / 88F8215)
+	- CN9132 (AP807 Quad + one internal CP115 + two external CP115 / 88F8215)
+
+  Core:
+	ARM Cortex A72
+
+  Homepage:
+	https://web.archive.org/web/20200803150818/https://www.marvell.com/products/infrastructure-processors/multi-core-processors/octeon-tx2/octeon-tx2-cn9130.html
+
+  Product Brief:
+	https://web.archive.org/web/20200803150818/https://www.marvell.com/content/dam/marvell/en/public-collateral/embedded-processors/marvell-infrastructure-processors-octeon-tx2-cn913x-product-brief-2020-02.pdf
+
+  Device tree files:
+	arch/arm64/boot/dts/marvell/cn913*
+
 Avanta family
 -------------
 
diff --git a/Documentation/asm-annotations.rst b/Documentation/asm-annotations.rst
index 76424e0431f4..f4bf0f6395fb 100644
--- a/Documentation/asm-annotations.rst
+++ b/Documentation/asm-annotations.rst
@@ -64,7 +64,7 @@ macros, it was decided that brand new macros should be introduced instead::
     of importing all the crappy, historic, essentially randomly chosen
     debug symbol macro names from the binutils and older kernels?
 
-.. _discussion: https://lkml.kernel.org/r/20170217104757.28588-1-jslaby@suse.cz
+.. _discussion: https://lore.kernel.org/r/20170217104757.28588-1-jslaby@suse.cz
 
 Macros Description
 ------------------
diff --git a/Documentation/block/queue-sysfs.rst b/Documentation/block/queue-sysfs.rst
index e8c74306f70a..3f569d532485 100644
--- a/Documentation/block/queue-sysfs.rst
+++ b/Documentation/block/queue-sysfs.rst
@@ -40,10 +40,11 @@ discard_max_hw_bytes (RO)
 -------------------------
 Devices that support discard functionality may have internal limits on
 the number of bytes that can be trimmed or unmapped in a single operation.
-The discard_max_bytes parameter is set by the device driver to the maximum
-number of bytes that can be discarded in a single operation. Discard
-requests issued to the device must not exceed this limit. A discard_max_bytes
-value of 0 means that the device does not support discard functionality.
+The `discard_max_hw_bytes` parameter is set by the device driver to the
+maximum number of bytes that can be discarded in a single operation.
+Discard requests issued to the device must not exceed this limit.
+A `discard_max_hw_bytes` value of 0 means that the device does not support
+discard functionality.
 
 discard_max_bytes (RW)
 ----------------------
diff --git a/Documentation/conf.py b/Documentation/conf.py
index 948a97d6387d..17f7cee56987 100644
--- a/Documentation/conf.py
+++ b/Documentation/conf.py
@@ -353,6 +353,9 @@ latex_elements = {
         \\setsansfont{DejaVu Sans}
         \\setromanfont{DejaVu Serif}
         \\setmonofont{DejaVu Sans Mono}
+        % Adjust \\headheight for fancyhdr
+        \\addtolength{\\headheight}{1.6pt}
+        \\addtolength{\\topmargin}{-1.6pt}
      ''',
 }
 
diff --git a/Documentation/dev-tools/checkpatch.rst b/Documentation/dev-tools/checkpatch.rst
index f0956e9ea2d8..b52452bc2963 100644
--- a/Documentation/dev-tools/checkpatch.rst
+++ b/Documentation/dev-tools/checkpatch.rst
@@ -710,6 +710,39 @@ Indentation and Line Breaks
 
     See: https://www.kernel.org/doc/html/latest/process/coding-style.html#breaking-long-lines-and-strings
 
+  **SPLIT_STRING**
+    Quoted strings that appear as messages in userspace and can be
+    grepped, should not be split across multiple lines.
+
+    See: https://lore.kernel.org/lkml/20120203052727.GA15035@leaf/
+
+  **MULTILINE_DEREFERENCE**
+    A single dereferencing identifier spanned on multiple lines like::
+
+      struct_identifier->member[index].
+      member = <foo>;
+
+    is generally hard to follow. It can easily lead to typos and so makes
+    the code vulnerable to bugs.
+
+    If fixing the multiple line dereferencing leads to an 80 column
+    violation, then either rewrite the code in a more simple way or if the
+    starting part of the dereferencing identifier is the same and used at
+    multiple places then store it in a temporary variable, and use that
+    temporary variable only at all the places. For example, if there are
+    two dereferencing identifiers::
+
+      member1->member2->member3.foo1;
+      member1->member2->member3.foo2;
+
+    then store the member1->member2->member3 part in a temporary variable.
+    It not only helps to avoid the 80 column violation but also reduces
+    the program size by removing the unnecessary dereferences.
+
+    But if none of the above methods work then ignore the 80 column
+    violation because it is much easier to read a dereferencing identifier
+    on a single line.
+
   **TRAILING_STATEMENTS**
     Trailing statements (for example after any conditional) should be
     on the next line.
@@ -845,6 +878,38 @@ Macros, Attributes and Symbols
     Use the `fallthrough;` pseudo keyword instead of
     `/* fallthrough */` like comments.
 
+  **TRAILING_SEMICOLON**
+    Macro definition should not end with a semicolon. The macro
+    invocation style should be consistent with function calls.
+    This can prevent any unexpected code paths::
+
+      #define MAC do_something;
+
+    If this macro is used within a if else statement, like::
+
+      if (some_condition)
+              MAC;
+
+      else
+              do_something;
+
+    Then there would be a compilation error, because when the macro is
+    expanded there are two trailing semicolons, so the else branch gets
+    orphaned.
+
+    See: https://lore.kernel.org/lkml/1399671106.2912.21.camel@joe-AO725/
+
+  **SINGLE_STATEMENT_DO_WHILE_MACRO**
+    For the multi-statement macros, it is necessary to use the do-while
+    loop to avoid unpredictable code paths. The do-while loop helps to
+    group the multiple statements into a single one so that a
+    function-like macro can be used as a function only.
+
+    But for the single statement macros, it is unnecessary to use the
+    do-while loop. Although the code is syntactically correct but using
+    the do-while loop is redundant. So remove the do-while loop for single
+    statement macros.
+
   **WEAK_DECLARATION**
     Using weak declarations like __attribute__((weak)) or __weak
     can have unintended link defects.  Avoid using them.
@@ -920,6 +985,11 @@ Functions and Variables
     Your compiler (or rather your loader) automatically does
     it for you.
 
+  **MULTIPLE_ASSIGNMENTS**
+    Multiple assignments on a single line makes the code unnecessarily
+    complicated. So on a single line assign value to a single variable
+    only, this makes the code more readable and helps avoid typos.
+
   **RETURN_PARENTHESES**
     return is not a function and as such doesn't need parentheses::
 
@@ -957,6 +1027,17 @@ Permissions
     Permission bits should use 4 digit octal permissions (like 0700 or 0444).
     Avoid using any other base like decimal.
 
+  **SYMBOLIC_PERMS**
+    Permission bits in the octal form are more readable and easier to
+    understand than their symbolic counterparts because many command-line
+    tools use this notation. Experienced kernel developers have been using
+    these traditional Unix permission bits for decades and so they find it
+    easier to understand the octal notation than the symbolic macros.
+    For example, it is harder to read S_IWUSR|S_IRUGO than 0644, which
+    obscures the developer's intent rather than clarifying it.
+
+    See: https://lore.kernel.org/lkml/CA+55aFw5v23T-zvDZp-MmD_EYxF8WbafwwB59934FV7g21uMGQ@mail.gmail.com/
+
 
 Spacing and Brackets
 --------------------
diff --git a/Documentation/filesystems/ext4/orphan.rst b/Documentation/filesystems/ext4/orphan.rst
index bb19ecd1b626..03cca178864b 100644
--- a/Documentation/filesystems/ext4/orphan.rst
+++ b/Documentation/filesystems/ext4/orphan.rst
@@ -12,41 +12,31 @@ track the inode as orphan so that in case of crash extra blocks allocated to
 the file get truncated.
 
 Traditionally ext4 tracks orphan inodes in a form of single linked list where
-superblock contains the inode number of the last orphan inode (s\_last\_orphan
+superblock contains the inode number of the last orphan inode (s_last_orphan
 field) and then each inode contains inode number of the previously orphaned
-inode (we overload i\_dtime inode field for this). However this filesystem
+inode (we overload i_dtime inode field for this). However this filesystem
 global single linked list is a scalability bottleneck for workloads that result
 in heavy creation of orphan inodes. When orphan file feature
-(COMPAT\_ORPHAN\_FILE) is enabled, the filesystem has a special inode
-(referenced from the superblock through s\_orphan_file_inum) with several
+(COMPAT_ORPHAN_FILE) is enabled, the filesystem has a special inode
+(referenced from the superblock through s_orphan_file_inum) with several
 blocks. Each of these blocks has a structure:
 
-.. list-table::
-   :widths: 8 8 24 40
-   :header-rows: 1
-
-   * - Offset
-     - Type
-     - Name
-     - Description
-   * - 0x0
-     - Array of \_\_le32 entries
-     - Orphan inode entries
-     - Each \_\_le32 entry is either empty (0) or it contains inode number of
-       an orphan inode.
-   * - blocksize - 8
-     - \_\_le32
-     - ob\_magic
-     - Magic value stored in orphan block tail (0x0b10ca04)
-   * - blocksize - 4
-     - \_\_le32
-     - ob\_checksum
-     - Checksum of the orphan block.
+============= ================ =============== ===============================
+Offset        Type             Name            Description
+============= ================ =============== ===============================
+0x0           Array of         Orphan inode    Each __le32 entry is either
+              __le32 entries   entries         empty (0) or it contains
+	                                       inode number of an orphan
+					       inode.
+blocksize-8   __le32           ob_magic        Magic value stored in orphan
+                                               block tail (0x0b10ca04)
+blocksize-4   __le32           ob_checksum     Checksum of the orphan block.
+============= ================ =============== ===============================
 
 When a filesystem with orphan file feature is writeably mounted, we set
-RO\_COMPAT\_ORPHAN\_PRESENT feature in the superblock to indicate there may
+RO_COMPAT_ORPHAN_PRESENT feature in the superblock to indicate there may
 be valid orphan entries. In case we see this feature when mounting the
 filesystem, we read the whole orphan file and process all orphan inodes found
 there as usual. When cleanly unmounting the filesystem we remove the
-RO\_COMPAT\_ORPHAN\_PRESENT feature to avoid unnecessary scanning of the orphan
+RO_COMPAT_ORPHAN_PRESENT feature to avoid unnecessary scanning of the orphan
 file and also make the filesystem fully compatible with older kernels.
diff --git a/Documentation/filesystems/f2fs.rst b/Documentation/filesystems/f2fs.rst
index 09de6ebbbdfa..6f3c6e91346d 100644
--- a/Documentation/filesystems/f2fs.rst
+++ b/Documentation/filesystems/f2fs.rst
@@ -283,7 +283,7 @@ compress_extension=%s	 Support adding specified extension, so that f2fs can enab
 			 For other files, we can still enable compression via ioctl.
 			 Note that, there is one reserved special extension '*', it
 			 can be set to enable compression for all files.
-nocompress_extension=%s	   Support adding specified extension, so that f2fs can disable
+nocompress_extension=%s	 Support adding specified extension, so that f2fs can disable
 			 compression on those corresponding files, just contrary to compression extension.
 			 If you know exactly which files cannot be compressed, you can use this.
 			 The same extension name can't appear in both compress and nocompress
diff --git a/Documentation/filesystems/proc.rst b/Documentation/filesystems/proc.rst
index 042c418f4090..8d7f141c6fc7 100644
--- a/Documentation/filesystems/proc.rst
+++ b/Documentation/filesystems/proc.rst
@@ -1857,19 +1857,19 @@ For example::
 This file contains lines of the form::
 
     36 35 98:0 /mnt1 /mnt2 rw,noatime master:1 - ext3 /dev/root rw,errors=continue
-    (1)(2)(3)   (4)   (5)      (6)      (7)   (8) (9)   (10)         (11)
-
-    (1) mount ID:  unique identifier of the mount (may be reused after umount)
-    (2) parent ID:  ID of parent (or of self for the top of the mount tree)
-    (3) major:minor:  value of st_dev for files on filesystem
-    (4) root:  root of the mount within the filesystem
-    (5) mount point:  mount point relative to the process's root
-    (6) mount options:  per mount options
-    (7) optional fields:  zero or more fields of the form "tag[:value]"
-    (8) separator:  marks the end of the optional fields
-    (9) filesystem type:  name of filesystem of the form "type[.subtype]"
-    (10) mount source:  filesystem specific information or "none"
-    (11) super options:  per super block options
+    (1)(2)(3)   (4)   (5)      (6)     (n…m) (m+1)(m+2) (m+3)         (m+4)
+
+    (1)   mount ID:        unique identifier of the mount (may be reused after umount)
+    (2)   parent ID:       ID of parent (or of self for the top of the mount tree)
+    (3)   major:minor:     value of st_dev for files on filesystem
+    (4)   root:            root of the mount within the filesystem
+    (5)   mount point:     mount point relative to the process's root
+    (6)   mount options:   per mount options
+    (n…m) optional fields: zero or more fields of the form "tag[:value]"
+    (m+1) separator:       marks the end of the optional fields
+    (m+2) filesystem type: name of filesystem of the form "type[.subtype]"
+    (m+3) mount source:    filesystem specific information or "none"
+    (m+4) super options:   per super block options
 
 Parsers should ignore all unrecognised optional fields.  Currently the
 possible optional fields are:
diff --git a/Documentation/kbuild/Kconfig.recursion-issue-02 b