linux-stable/Documentation/filesystems
NeilBrown 84dacdbd53 mm: document and polish read-ahead code
Add some "big-picture" documentation for read-ahead and polish the code
to make it fit this documentation.

The meaning of ->async_size is clarified to match its name.  i.e.  Any
request to ->readahead() has a sync part and an async part.  The caller
will wait for the sync pages to complete, but will not wait for the
async pages.  The first async page is still marked PG_readahead

Note that the current function names page_cache_sync_ra() and
page_cache_async_ra() are misleading.  All ra request are partly sync
and partly async, so either part can be empty.  A page_cache_sync_ra()
request will usually set ->async_size non-zero, implying it is not all
synchronous.

When a non-zero req_count is passed to page_cache_async_ra(), the
implication is that some prefix of the request is synchronous, though
the calculation made there is incorrect - I haven't tried to fix it.

Link: https://lkml.kernel.org/r/164549983734.9187.11586890887006601405.stgit@noble.brown
Signed-off-by: NeilBrown <neilb@suse.de>
Cc: Anna Schumaker <Anna.Schumaker@Netapp.com>
Cc: Chao Yu <chao@kernel.org>
Cc: Darrick J. Wong <djwong@kernel.org>
Cc: Ilya Dryomov <idryomov@gmail.com>
Cc: Jaegeuk Kim <jaegeuk@kernel.org>
Cc: Jan Kara <jack@suse.cz>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Lars Ellenberg <lars.ellenberg@linbit.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Paolo Valente <paolo.valente@linaro.org>
Cc: Philipp Reisner <philipp.reisner@linbit.com>
Cc: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-22 15:57:00 -07:00
..
caching fscache: Rewrite documentation 2022-01-11 22:13:01 +00:00
cifs docs: filesystem: cifs: ksmbd: Fix small layout issues 2021-11-25 00:09:26 -06:00
ext4 ext4: docs: Take out unneeded escaping 2021-10-07 08:46:02 -06:00
nfs nfs: reexport documentation 2021-09-21 17:51:47 -04:00
spufs
9p.rst Replace HTTP links with HTTPS ones: 9P FILE SYSTEM 2020-07-13 11:28:12 -06:00
adfs.rst
affs.rst affs: fix basic permission bits to actually work 2020-08-31 12:20:31 +02:00
afs.rst AFS: Documentation: fix a few typos in afs.rst 2021-01-21 14:06:00 -07:00
api-summary.rst block: move fs/block_dev.c to block/bdev.c 2021-09-07 08:39:40 -06:00
autofs-mount-control.rst Documentation: filesystems: autofs-mount-control: drop doubled words 2020-07-05 14:44:29 -06:00
autofs.rst docs: filesystems: Fix grammatical error "with" to "which" 2021-11-15 02:54:37 -07:00
automount-support.rst
befs.rst
bfs.rst
btrfs.rst
ceph.rst doc: document new CephFS mount device syntax 2022-01-13 13:40:06 +01:00
coda.rst Documentation: coda: annotate duplicated words 2020-07-13 10:02:32 -06:00
configfs.rst Documentation: filesystems: configfs: drop doubled word 2020-07-05 14:44:29 -06:00
cramfs.rst
dax.rst Documentation/filesystem/dax: DAX on virtiofs 2021-12-14 11:09:37 +01:00
debugfs.rst debugfs: remove return value of debugfs_create_bool() 2021-05-21 20:59:03 +02:00
devpts.rst
directory-locking.rst Documentation: filesystems: directory-locking: drop doubled word 2020-07-05 14:44:29 -06:00
dlmfs.rst ocfs2: replace HTTP links with HTTPS ones 2020-08-07 11:33:22 -07:00
dnotify.rst
ecryptfs.rst
efivarfs.rst docs: filesystems: add info about efivars content 2020-05-25 18:59:59 -06:00
erofs.rst erofs: add sysfs interface 2021-12-08 09:40:37 +08:00
ext2.rst docs: fix a cross-ref 2021-06-13 17:02:46 -06:00
ext3.rst
f2fs.rst f2fs: support fault injection to f2fs_trylock_op() 2022-01-04 13:20:56 -08:00
fiemap.rst A lot of bug fixes and cleanups for ext4, including: 2020-06-05 16:19:28 -07:00
files.rst file: Rename fcheck lookup_fd_rcu 2020-12-10 12:40:07 -06:00
fscrypt.rst fscrypt: allow 256-bit master keys with AES-256-XTS 2021-09-22 11:29:38 -07:00
fsverity.rst fs-verity: support reading signature with ioctl 2021-02-07 14:51:19 -08:00
fuse-io.rst
fuse.rst fuse: update project homepage 2020-09-04 11:32:10 +02:00
gfs2-glocks.rst docs: filesystems: convert gfs2-glocks.txt to ReST 2020-06-02 19:45:05 +02:00
gfs2-uevents.rst
gfs2.rst Documentation: Update filesystems/gfs2.rst 2020-12-01 00:25:20 +01:00
hfs.rst Replace HTTP links with HTTPS ones: Documentation/filesystems 2020-06-26 11:14:12 -06:00
hfsplus.rst
hpfs.rst Replace HTTP links with HTTPS ones: Documentation/filesystems 2020-06-26 11:14:12 -06:00
idmappings.rst docs: update mapping documentation 2021-12-03 18:58:11 +01:00
index.rst Documentation: remove reference to now removed mandatory-locking doc 2021-10-05 06:02:53 -04:00
inotify.rst
isofs.rst
journalling.rst jbd2: drop jbd2_fc_init documentation 2020-11-06 23:01:03 -05:00
locking.rst doc: fs: remove bdev_try_to_free_page related doc 2021-12-23 12:40:53 -07:00
locks.rst docs: fs: locks.rst: update comment about mandatory file locking 2021-10-19 06:48:21 -04:00
mount_api.rst Documentation: mount_api: change kernel log wording 2020-12-03 15:53:13 -07:00
netfs_library.rst netfs, cachefiles: Add a method to query presence of data in the cache 2022-02-01 10:29:18 -06:00
nilfs2.rst
ntfs.rst
ntfs3.rst Doc/fs/ntfs3: Fix rst format and make it cleaner 2021-09-20 18:53:12 +03:00
ocfs2-online-filecheck.rst
ocfs2.rst ocfs2: replace HTTP links with HTTPS ones 2020-08-07 11:33:22 -07:00
omfs.rst Replace HTTP links with HTTPS ones: OMFS 2020-07-13 11:24:43 -06:00
orangefs.rst
overlayfs.rst ovl: skip checking lower file's i_writecount on truncate 2021-08-17 11:47:44 +02:00
path-lookup.rst Merge branch 'work.namei' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2021-07-03 11:41:14 -07:00
path-lookup.txt Replace HTTP links with HTTPS ones: documentation 2020-06-08 09:30:19 -06:00
porting.rst Merge branch 'work.namei' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2021-07-03 11:41:14 -07:00
proc.rst mm: add a field to store names for private anonymous memory 2022-01-15 16:30:27 +02:00
qnx6.rst
quota.rst quota: Fixup http links in quota doc 2020-07-09 08:14:01 +02:00
ramfs-rootfs-initramfs.rst Documentation: Fix intiramfs script name 2021-07-18 23:48:14 +09:00
relay.rst
romfs.rst
seq_file.rst seq_file: document how per-entry resources are managed. 2021-02-26 09:41:05 -08:00
sharedsubtree.rst
splice.rst
squashfs.rst
sysfs.rst Driver Core patches for 5.10-rc1 2020-10-14 16:09:32 -07:00
sysv-fs.rst
tmpfs.rst tmpfs: fix Documentation nits 2020-12-15 12:13:39 -08:00
ubifs-authentication.rst docs: ubifs-authentication: Add a top-level heading 2020-09-09 11:53:33 -06:00
ubifs.rst
udf.rst udf: Replace HTTP links with HTTPS ones 2020-07-14 14:37:39 +02:00
vfat.rst docs: filesystems: Fix a mundane typo 2021-03-25 11:51:23 -06:00
vfs.rst mm: document and polish read-ahead code 2022-03-22 15:57:00 -07:00
virtiofs.rst
xfs-delayed-logging-design.rst
xfs-self-describing-metadata.rst New code for 5.8: 2020-06-02 19:21:40 -07:00
zonefs.rst zonefs: document the explicit-open mount option 2020-09-15 18:32:58 +09:00