linux/Documentation/filesystems
Linus Torvalds a11e1d432b Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL
The poll() changes were not well thought out, and completely
unexplained.  They also caused a huge performance regression, because
"->poll()" was no longer a trivial file operation that just called down
to the underlying file operations, but instead did at least two indirect
calls.

Indirect calls are sadly slow now with the Spectre mitigation, but the
performance problem could at least be largely mitigated by changing the
"->get_poll_head()" operation to just have a per-file-descriptor pointer
to the poll head instead.  That gets rid of one of the new indirections.

But that doesn't fix the new complexity that is completely unwarranted
for the regular case.  The (undocumented) reason for the poll() changes
was some alleged AIO poll race fixing, but we don't make the common case
slower and more complex for some uncommon special case, so this all
really needs way more explanations and most likely a fundamental
redesign.

[ This revert is a revert of about 30 different commits, not reverted
  individually because that would just be unnecessarily messy  - Linus ]

Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-06-28 10:40:47 -07:00
..
caching fscache: Pass object size in rather than calling back for it 2018-04-06 14:05:14 +01:00
cifs cifs: minor documentation updates 2018-06-15 02:38:07 -05:00
configfs fs: configfs: don't return anything from drop_link 2016-12-01 10:50:49 +01:00
nfs ipconfig: Write NTP server IPs to /proc/net/ipconfig/ntp_servers 2018-04-24 13:40:42 -04:00
pohmelfs Documentation: fix common spelling mistakes 2016-04-28 07:51:59 -06:00
9p.txt
00-INDEX Staging/IIO patches for 4.18-rc1 2018-06-09 10:32:39 -07:00
adfs.txt
affs.txt
afs.txt afs: Implement @sys substitution handling 2018-04-09 21:12:31 +01:00
autofs-mount-control.txt autofs: use autofs instead of autofs4 in documentation 2018-06-07 17:34:39 -07:00
autofs.txt autofs: use autofs instead of autofs4 in documentation 2018-06-07 17:34:39 -07:00
automount-support.txt autofs: use autofs instead of autofs4 in documentation 2018-06-07 17:34:39 -07:00
befs.txt
bfs.txt Tigran has moved 2017-05-12 15:57:15 -07:00
btrfs.txt Documentation: btrfs: remove usage specific information 2016-03-11 17:02:09 +01:00
ceph.txt ceph: update description of some mount options 2018-06-04 20:46:02 +02:00
coda.txt
conf.py docs-rst: convert filesystems book to ReST 2017-05-16 08:44:08 -03:00
cramfs.txt cramfs: rehabilitate it 2017-10-15 00:47:23 -04:00
dax.txt powerpc/cell: Remove axonram driver 2018-01-28 17:00:36 +11:00
debugfs.txt
devpts.txt devpts: Make each mount of devpts an independent filesystem. 2016-06-05 10:36:01 -07:00
directory-locking vfs: remove unused i_op->rename 2016-09-27 11:03:58 +02:00
dlmfs.txt
dnotify.txt Documentation: fix selftests related file refs 2017-10-19 12:58:21 -06:00
ecryptfs.txt
efivarfs.txt efi: Make efivarfs entries immutable by default 2016-02-10 16:25:52 +00:00
exofs.txt
ext2.txt fs/*/Kconfig: drop links to 404-compliant http://acl.bestbits.at 2018-01-01 12:45:37 -07:00
ext3.txt
ext4.txt Only miscellaneous cleanups and bug fixes for ext4 this cycle. 2018-02-03 13:49:22 -08:00
f2fs.txt f2fs: add fsync_mode=nobarrier for non-atomic files 2018-05-29 12:04:08 -07:00
fiemap.txt
files.txt
fscrypt.rst fscrypt: add Speck128/256 support 2018-05-20 16:35:51 -04:00
fuse-io.txt fuse: add writeback documentation 2018-03-20 17:11:45 +01:00
fuse.txt
gfs2-glocks.txt GFS2: Minor improvements to comments and documentation 2018-04-12 10:07:51 -07:00
gfs2-uevents.txt
gfs2.txt
hfs.txt
hfsplus.txt
hpfs.txt
index.rst fscrypt: add a documentation file for filesystem-level encryption 2017-10-31 13:49:24 -04:00
inotify.txt
isofs.txt
jfs.txt
Locking Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
locks.txt docs: fix locations of several documents that got moved 2016-10-24 08:12:35 -02:00
mandatory-locking.txt
nilfs2.txt MAINTAINERS, nilfs2: change project home URLs 2018-01-13 10:42:48 -08:00
ntfs.txt
ocfs2-online-filecheck.txt Doc: ocfs: Fix typo in filesystems/ocfs2-online-filecheck.txt 2016-07-01 16:17:15 -06:00
ocfs2.txt
omfs.txt
orangefs.txt Orangefs: documentation updates 2018-04-04 14:05:48 -04:00
overlayfs.txt ovl: update documentation for unionmount-testsuite 2018-05-31 11:06:10 +02:00
path-lookup.md autofs: use autofs instead of autofs4 in documentation 2018-06-07 17:34:39 -07:00
path-lookup.txt
porting vfs: grab the lock instead of blocking in __fd_install during resizing 2017-11-05 18:58:07 -05:00
proc.txt docs/vm: move numa_memory_policy.rst to Documentation/admin-guide/mm 2018-05-08 09:31:31 -06:00
qnx6.txt Documentation: fix common spelling mistakes 2016-04-28 07:51:59 -06:00
quota.txt scripts/spelling.txt: add "an user" pattern and fix typo instances 2017-02-27 18:43:46 -08:00
ramfs-rootfs-initramfs.txt
relay.txt
romfs.txt
seq_file.txt
sharedsubtree.txt doc: fix grammar 2016-03-09 15:33:06 -07:00
spufs.txt
squashfs.txt
sysfs-pci.txt PCI: Add pci_mmap_resource_range() and use it for ARM64 2017-04-20 08:47:47 -05:00
sysfs-tagging.txt
sysfs.txt kallsyms: remove print_symbol() function 2018-01-16 16:59:55 +01:00
sysv-fs.txt
tmpfs.txt docs/vm: move numa_memory_policy.rst to Documentation/admin-guide/mm 2018-05-08 09:31:31 -06:00
ubifs.txt
udf.txt udf: Remove never implemented mount options 2018-02-27 10:25:33 +01:00
ufs.txt
vfat.txt Documentation/filesystems/vfat.txt: fix a remark that implies UCS2 2017-12-21 13:39:28 -07:00
vfs.txt Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
xfs-delayed-logging-design.txt
xfs-self-describing-metadata.txt
xfs.txt xfs: Change URL for the project in xfs.txt 2018-03-21 09:33:04 -06:00