block: move fs/block_dev.c to block/bdev.c

Move it together with the rest of the block layer.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20210907141303.1371844-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>

Documentation: filesystems api-summary: add namespace.c

Add fs/namespace.c to the filesystems api-summary docbook.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Link: https://lore.kernel.org/r/20210318025227.4162-2-rdunlap@infradead.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Docs: add fs/eventpoll to docbooks

Add fs/eventpoll.c to the filesystem api-summary book.

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Link: https://lore.kernel.org/r/20210210042526.23174-2-rdunlap@infradead.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

docs: fs: api-summary.rst: get rid of kernel-doc include

The direct-io.c file used to have just two exported symbols:

- dio_end_io()
- __blockdev_direct_IO()

The first one was removed by changeset
c33fe275b530 ("fs: remove no longer used dio_end_io()")

And the last one is used on most places indirectly, via
the inline macro blockdev_direct_IO() provided by fs.h.
Yet, neither the macro or the function have kernel-doc
markups.

So, drop the inclusion of fs/direct-io.c at the docs.

Fixes: c33fe275b530 ("fs: remove no longer used dio_end_io()")
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Link: https://lore.kernel.org/r/d0a9fffedca102633c168adaf157f34288a4ea67.1603791716.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

docs: no structured comments in fs/file_table.c

Remove the kernel-doc directive, since there are only warnings to be found
there.

Signed-off-by: Jonathan Corbet <corbet@lwn.net>

docs: Bring some order to filesystem documentation

Documentation/filesystems is, like much of the rest of the kernel's
documentation, a jumble of unorganized information. Split the
documentation into categories and try to bring some order to the top-level
index.rst files. No text changes other than a few section-introductory
blurbs; this is all just moving stuff around.

Cc: linux-fsdevel@vger.kernel.org
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>