Merge tag 'docs-6.1' of git://git.lwn.net/linux

Pull documentation updates from Jonathan Corbet:
 "There's not a huge amount of activity in the docs tree this time
  around, but a few significant changes even so:

   - A complete rewriting of the top-level index.rst file, which mostly
     reflects itself in a redone top page in the HTML-rendered docs. The
     hope is that the new organization will be a friendlier starting
     point for both users and developers.

   - Some math-rendering improvements.

   - A coding-style.rst update on the use of BUG() and WARN()

   - A big maintainer-PHP guide update.

   - Some code-of-conduct updates

   - More Chinese translation work

  Plus the usual pile of typo fixes, corrections, and updates"

* tag 'docs-6.1' of git://git.lwn.net/linux: (66 commits)
  checkpatch: warn on usage of VM_BUG_ON() and other BUG variants
  coding-style.rst: document BUG() and WARN() rules ("do not crash the kernel")
  Documentation: devres: add missing IO helper
  Documentation: devres: update IRQ helper
  Documentation/mm: modify page_referenced to folio_referenced
  Documentation/CoC: Reflect current CoC interpretation and practices
  docs/doc-guide: Add documentation on SPHINX_IMGMATH
  docs: process/5.Posting.rst: clarify use of Reported-by: tag
  docs, kprobes: Fix the wrong location of Kprobes
  docs: add a man-pages link to the front page
  docs: put atomic*.txt and memory-barriers.txt into the core-api book
  docs: move asm-annotations.rst into core-api
  docs: remove some index.rst cruft
  docs: reconfigure the HTML left column
  docs: Rewrite the front page
  docs: promote the title of process/index.rst
  Documentation: devres: add missing SPI helper
  Documentation: devres: add missing PINCTRL helpers
  docs: hugetlbpage.rst: fix a typo of hugepage size
  docs/zh_CN: Add new translation of admin-guide/bootconfig.rst
  ...

1 files changed, 58 insertions, 0 deletions

diff --git a/Documentation/subsystem-apis.rst b/Documentation/subsystem-apis.rst
new file mode 100644
index 000000000000..af65004a80aa
--- /dev/null
+++ b/Documentation/subsystem-apis.rst
@@ -0,0 +1,58 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+==============================
+Kernel subsystem documentation
+==============================
+
+These books get into the details of how specific kernel subsystems work
+from the point of view of a kernel developer.  Much of the information here
+is taken directly from the kernel source, with supplemental material added
+as needed (or at least as we managed to add it — probably *not* all that is
+needed).
+
+**Fixme**: much more organizational work is needed here.
+
+.. toctree::
+   :maxdepth: 1
+
+   driver-api/index
+   core-api/index
+   locking/index
+   accounting/index
+   block/index
+   cdrom/index
+   cpu-freq/index
+   fb/index
+   fpga/index
+   hid/index
+   i2c/index
+   iio/index
+   isdn/index
+   infiniband/index
+   leds/index
+   netlabel/index
+   networking/index
+   pcmcia/index
+   power/index
+   target/index
+   timers/index
+   spi/index
+   w1/index
+   watchdog/index
+   virt/index
+   input/index
+   hwmon/index
+   gpu/index
+   security/index
+   sound/index
+   crypto/index
+   filesystems/index
+   mm/index
+   bpf/index
+   usb/index
+   PCI/index
+   scsi/index
+   misc-devices/index
+   scheduler/index
+   mhi/index
+   peci/index