IF YOU WOULD LIKE TO GET AN ACCOUNT, please write an
email to Administrator. User accounts are meant only to access repo
and report issues and/or generate pull requests.
This is a purpose-specific Git hosting for
BaseALT
projects. Thank you for your understanding!
Только зарегистрированные пользователи имеют доступ к сервису!
Для получения аккаунта, обратитесь к администратору.
No inode->put_link operation anymore. We use delayed_call to
deal with link destruction. Cookie has been replaced with
struct delayed_call.
Related commit: commit fceef393a538 ("switch ->get_link() to
delayed_call, kill ->put_link()")
Signed-off-by: Fox Chen <foxhlchen@gmail.com>
Reviewed-by: NeilBrown <neilb@suse.de>
Link: https://lore.kernel.org/r/20210527091618.287093-9-foxhlchen@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
follow_link has been replaced by get_link() which can be
called in RCU mode.
see commit: commit 6b2553918d8b ("replace ->follow_link() with
new method that could stay in RCU mode")
Signed-off-by: Fox Chen <foxhlchen@gmail.com>
Reviewed-by: NeilBrown <neilb@suse.de>
Link: https://lore.kernel.org/r/20210527091618.287093-8-foxhlchen@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Add macro name MAXSYMLINKS to the symlink limit description, so
that it is consistent with path name length description above.
Signed-off-by: Fox Chen <foxhlchen@gmail.com>
Reviewed-by: NeilBrown <neilb@suse.de>
Link: https://lore.kernel.org/r/20210527091618.287093-7-foxhlchen@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
No filename_mountpoint any more
see commit: commit 161aff1d93ab ("LOOKUP_MOUNTPOINT:
fold path_mountpointat() into path_lookupat()")
Without filename_mountpoint and path_mountpoint(), the
numbers should be four & three:
"These four correspond roughly to the three path_*() functions"
Signed-off-by: Fox Chen <foxhlchen@gmail.com>
Reviewed-by: NeilBrown <neilb@suse.de>
Link: https://lore.kernel.org/r/20210527091618.287093-6-foxhlchen@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
traling_symlink() was merged into lookup_last, do_last().
do_last() has later been split into open_last_lookups()
and do_open().
see related commit: commit c5971b8c6354 ("take post-lookup
part of do_last() out of loop")
Signed-off-by: Fox Chen <foxhlchen@gmail.com>
Reviewed-by: NeilBrown <neilb@suse.de>
Link: https://lore.kernel.org/r/20210527091618.287093-5-foxhlchen@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
path_mountpoint() doesn't exist anymore. Have been folded
into path_lookup_at when flag is set with LOOKUP_MOUNTPOINT.
Check commit: commit 161aff1d93abf0e ("LOOKUP_MOUNTPOINT: fold
path_mountpointat() into path_lookupat()")
Signed-off-by: Fox Chen <foxhlchen@gmail.com>
Reviewed-by: NeilBrown <neilb@suse.de>
Link: https://lore.kernel.org/r/20210527091618.287093-4-foxhlchen@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
No path_to_namei() anymore, step_into() will be called.
Related commit: commit c99687a03a78 ("fold path_to_nameidata()
into its only remaining caller")
Signed-off-by: Fox Chen <foxhlchen@gmail.com>
Reviewed-by: NeilBrown <neilb@suse.de>
Link: https://lore.kernel.org/r/20210527091618.287093-3-foxhlchen@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
No follow_managed() anymore, handle_mounts(),
traverse_mounts(), will do the job.
see commit 9deed3ebca24 ("new helper: traverse_mounts()")
Signed-off-by: Fox Chen <foxhlchen@gmail.com>
Reviewed-by: NeilBrown <neilb@suse.de>
Link: https://lore.kernel.org/r/20210527091618.287093-2-foxhlchen@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
The conversion tools used during DocBook/LaTeX/html/Markdown->ReST
conversion and some cut-and-pasted text contain some characters that
aren't easily reachable on standard keyboards and/or could cause
troubles when parsed by the documentation build system.
Replace the occurences of the following characters:
- U+2217 ('∗'): ASTERISK OPERATOR
use ASCII asterisk instead of the ASTERISK OPERATOR
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Acked-by: Theodore Ts'o <tytso@mit.edu>
Link: https://lore.kernel.org/r/c5c3c384c48779ca7c9dcd90183cefe20ac82928.1623826294.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Replacement is called copy_page_from_iter_atomic(); unlike the old primitive the
callers do *not* need to do iov_iter_advance() after it. In case when they end
up consuming less than they'd been given they need to do iov_iter_revert() on
everything they had not consumed. That, however, needs to be done only on slow
paths.
All in-tree callers converted. And that kills the last user of iterate_all_kinds()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Change the file extension and add the rst constructs to integrate this
doc to the documentation infrastructure and take advantage of rst
features.
Signed-off-by: Igor Matheus Andrade Torrente <igormtorrente@gmail.com>
Link: https://lore.kernel.org/r/20210531130515.10309-1-igormtorrente@gmail.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Replace the per-block device bd_mutex with a per-gendisk open_mutex,
thus simplifying locking wherever we deal with partitions.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Acked-by: Roger Pau Monné <roger.pau@citrix.com>
Link: https://lore.kernel.org/r/20210525061301.2242282-4-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add ksmbd/nfsd interoperability to feature table and sync with a table in
patch cover letter.
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
added documentation for cifsd. There, it points to a file
named:
Documentation/configuration.txt
This confuses Kernel scripts, as they think that this is a
document within the Kernel tree, instead of a file from
some other place.
Replace it by an hyperlink to the ksmbd-tools tree, in order
to avoid false-positives.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Since more than one file is in the cifs document directory,
This patch add an index.rst.
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Add work flow of cifsd and feature stats table.
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Stephen reported a warning message from cifsd.rst file.
Documentation/filesystems/cifs/cifsd.rst: WARNING: document isn't
included in any toctree
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Stephen reported a warning message from cifsd.rst file.
Documentation/filesystems/cifs/cifsd.rst:3: WARNING: Title overline too
short.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
This adds server handler for central processing,
transport layers(tcp, rdma, ipc) and a document describing cifsd
architecture.
Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Hyunchul Lee <hyc.lee@gmail.com>
Acked-by: Ronnie Sahlberg <lsahlber@redhat.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
In this round, we added a new mount option, "checkpoint_merge", which introduces
a kernel thread dealing with the f2fs checkpoints. Once we start to manage the
IO priority along with blk-cgroup, the checkpoint operation can be processed in
a lower priority under the process context. Since the checkpoint holds all the
filesystem operations, we give a higher priority to the checkpoint thread all
the time.
Enhancement:
- introduce gc_merge mount option to introduce a checkpoint thread
- improve to run discard thread efficiently
- allow modular compression algorithms
- expose # of overprivision segments to sysfs
- expose runtime compression stat to sysfs
Bug fix:
- fix OOB memory access by the node id lookup
- avoid touching checkpointed data in the checkpoint-disabled mode
- fix the resizing flow to avoid kernel panic and race conditions
- fix block allocation issues on pinned files
- address some swapfile issues
- fix hugtask problem and kernel panic during atomic write operations
- don't start checkpoint thread in RO
And, we've cleaned up some kernel coding style and build warnings. In addition,
we fixed some minor race conditions and error handling routines.
-----BEGIN PGP SIGNATURE-----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=P5uk
-----END PGP SIGNATURE-----
Merge tag 'f2fs-for-5.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs
Pull f2fs updates from Jaegeuk Kim:
"In this round, we added a new mount option, "checkpoint_merge", which
introduces a kernel thread dealing with the f2fs checkpoints. Once we
start to manage the IO priority along with blk-cgroup, the checkpoint
operation can be processed in a lower priority under the process
context. Since the checkpoint holds all the filesystem operations, we
give a higher priority to the checkpoint thread all the time.
Enhancements:
- introduce gc_merge mount option to introduce a checkpoint thread
- improve to run discard thread efficiently
- allow modular compression algorithms
- expose # of overprivision segments to sysfs
- expose runtime compression stat to sysfs
Bug fixes:
- fix OOB memory access by the node id lookup
- avoid touching checkpointed data in the checkpoint-disabled mode
- fix the resizing flow to avoid kernel panic and race conditions
- fix block allocation issues on pinned files
- address some swapfile issues
- fix hugtask problem and kernel panic during atomic write operations
- don't start checkpoint thread in RO
And, we've cleaned up some kernel coding style and build warnings. In
addition, we fixed some minor race conditions and error handling
routines"
* tag 'f2fs-for-5.13-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (48 commits)
f2fs: drop inplace IO if fs status is abnormal
f2fs: compress: remove unneed check condition
f2fs: clean up left deprecated IO trace codes
f2fs: avoid using native allocate_segment_by_default()
f2fs: remove unnecessary struct declaration
f2fs: fix to avoid NULL pointer dereference
f2fs: avoid duplicated codes for cleanup
f2fs: document: add description about compressed space handling
f2fs: clean up build warnings
f2fs: fix the periodic wakeups of discard thread
f2fs: fix to avoid accessing invalid fio in f2fs_allocate_data_block()
f2fs: fix to avoid GC/mmap race with f2fs_truncate()
f2fs: set checkpoint_merge by default
f2fs: Fix a hungtask problem in atomic write
f2fs: fix to restrict mount condition on readonly block device
f2fs: introduce gc_merge mount option
f2fs: fix to cover __allocate_new_section() with curseg_lock
f2fs: fix wrong alloc_type in f2fs_do_replace_block
f2fs: delete empty compress.h
f2fs: fix a typo in inode.c
...
casefold, ensure that deleted file names are cleared in directory
blocks by zeroing directory entries when they are unlinked or moved as
part of a hash tree node split. We also improve the block allocator's
performance on a freshly mounted file system by prefetching block
bitmaps.
There are also the usual cleanups and bug fixes, including fixing a
page cache invalidation race when there is mixed buffered and direct
I/O and the block size is less than page size, and allow the dax flag
to be set and cleared on inline directories.
-----BEGIN PGP SIGNATURE-----
iQEzBAABCAAdFiEEK2m5VNv+CHkogTfJ8vlZVpUNgaMFAmCLei4ACgkQ8vlZVpUN
gaPZkgf/VH08xjMf3VthC+BpvVmChQXfV4yjigHbO2pmPyYWZhyJzkEGCQD8u2eB
b7ShW+B1NCifcTU34xAkKHwEtakzzEv3WIMrT1oZNWrpfo8tt850EkwQggaGGDpd
/HnP1/wLtziJ5hE6DwutmX7qB4VFghVj898MjDrEPSOBqItOjWps9mn/JWL7SHyI
Dqzhf5XZTYPaXWuJmSmKw3q8O70JDHnZe/rRWlfX1jLI5KDtqp71Nw1B+gszUB66
IUdncyZKvInsyjYhkbCQ8U6WFih82MrbKeuGYDp/RFvg5eMELEYkwT9j0ofuDHq8
zn62sAlbOXv1DiqkPDHKVm9GkHx8/g==
=UpnH
-----END PGP SIGNATURE-----
Merge tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
Pull ext4 updates from Ted Ts'o:
"New features for ext4 this cycle include support for encrypted
casefold, ensure that deleted file names are cleared in directory
blocks by zeroing directory entries when they are unlinked or moved as
part of a hash tree node split. We also improve the block allocator's
performance on a freshly mounted file system by prefetching block
bitmaps.
There are also the usual cleanups and bug fixes, including fixing a
page cache invalidation race when there is mixed buffered and direct
I/O and the block size is less than page size, and allow the dax flag
to be set and cleared on inline directories"
* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4: (32 commits)
ext4: wipe ext4_dir_entry2 upon file deletion
ext4: Fix occasional generic/418 failure
fs: fix reporting supported extra file attributes for statx()
ext4: allow the dax flag to be set and cleared on inline directories
ext4: fix debug format string warning
ext4: fix trailing whitespace
ext4: fix various seppling typos
ext4: fix error return code in ext4_fc_perform_commit()
ext4: annotate data race in jbd2_journal_dirty_metadata()
ext4: annotate data race in start_this_handle()
ext4: fix ext4_error_err save negative errno into superblock
ext4: fix error code in ext4_commit_super
ext4: always panic when errors=panic is specified
ext4: delete redundant uptodate check for buffer
ext4: do not set SB_ACTIVE in ext4_orphan_cleanup()
ext4: make prefetch_block_bitmaps default
ext4: add proc files to monitor new structures
ext4: improve cr 0 / cr 1 group scanning
ext4: add MB_NUM_ORDERS macro
ext4: add mballoc stats proc file
...
-----BEGIN PGP SIGNATURE-----
iHUEABYIAB0WIQSQHSd0lITzzeNWNm3h3BK/laaZPAUCYIwTsgAKCRDh3BK/laaZ
PDktAP41eScbCiFzXDRjXw9S7Wfd8HEct0y1p+9BUh8m3VdHfwEA0pDlJWNaJdYW
nFixPJ5GsAfxo+1ags0vn06CUS/K4gA=
=QlbJ
-----END PGP SIGNATURE-----
Merge tag 'ovl-update-5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs
Pull overlayfs update from Miklos Szeredi:
- Fix a regression introduced in 5.2 that resulted in valid overlayfs
mounts being rejected with ELOOP (Too many levels of symbolic links)
- Fix bugs found by various tools
- Miscellaneous improvements and cleanups
* tag 'ovl-update-5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
ovl: add debug print to ovl_do_getxattr()
ovl: invalidate readdir cache on changes to dir with origin
ovl: allow upperdir inside lowerdir
ovl: show "userxattr" in the mount data
ovl: trivial typo fixes in the file inode.c
ovl: fix misspellings using codespell tool
ovl: do not copy attr several times
ovl: remove ovl_map_dev_ino() return value
ovl: fix error for ovl_fill_super()
ovl: fix missing revert_creds() on error path
ovl: fix leaked dentry
ovl: restrict lower null uuid for "xino=auto"
ovl: check that upperdir path is not on a read-only mount
ovl: plumb through flush method
-----BEGIN PGP SIGNATURE-----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=tZgy
-----END PGP SIGNATURE-----
Merge tag 'netfs-lib-20210426' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs
Pull network filesystem helper library updates from David Howells:
"Here's a set of patches for 5.13 to begin the process of overhauling
the local caching API for network filesystems. This set consists of
two parts:
(1) Add a helper library to handle the new VM readahead interface.
This is intended to be used unconditionally by the filesystem
(whether or not caching is enabled) and provides a common
framework for doing caching, transparent huge pages and, in the
future, possibly fscrypt and read bandwidth maximisation. It also
allows the netfs and the cache to align, expand and slice up a
read request from the VM in various ways; the netfs need only
provide a function to read a stretch of data to the pagecache and
the helper takes care of the rest.
(2) Add an alternative fscache/cachfiles I/O API that uses the kiocb
facility to do async DIO to transfer data to/from the netfs's
pages, rather than using readpage with wait queue snooping on one
side and vfs_write() on the other. It also uses less memory, since
it doesn't do buffered I/O on the backing file.
Note that this uses SEEK_HOLE/SEEK_DATA to locate the data
available to be read from the cache. Whilst this is an improvement
from the bmap interface, it still has a problem with regard to a
modern extent-based filesystem inserting or removing bridging
blocks of zeros. Fixing that requires a much greater overhaul.
This is a step towards overhauling the fscache API. The change is
opt-in on the part of the network filesystem. A netfs should not try
to mix the old and the new API because of conflicting ways of handling
pages and the PG_fscache page flag and because it would be mixing DIO
with buffered I/O. Further, the helper library can't be used with the
old API.
This does not change any of the fscache cookie handling APIs or the
way invalidation is done at this time.
In the near term, I intend to deprecate and remove the old I/O API
(fscache_allocate_page{,s}(), fscache_read_or_alloc_page{,s}(),
fscache_write_page() and fscache_uncache_page()) and eventually
replace most of fscache/cachefiles with something simpler and easier
to follow.
This patchset contains the following parts:
- Some helper patches, including provision of an ITER_XARRAY iov
iterator and a function to do readahead expansion.
- Patches to add the netfs helper library.
- A patch to add the fscache/cachefiles kiocb API.
- A pair of patches to fix some review issues in the ITER_XARRAY and
read helpers as spotted by Al and Willy.
Jeff Layton has patches to add support in Ceph for this that he
intends for this merge window. I have a set of patches to support AFS
that I will post a separate pull request for.
With this, AFS without a cache passes all expected xfstests; with a
cache, there's an extra failure, but that's also there before these
patches. Fixing that probably requires a greater overhaul. Ceph also
passes the expected tests.
I also have patches in a separate branch to tidy up the handling of
PG_fscache/PG_private_2 and their contribution to page refcounting in
the core kernel here, but I haven't included them in this set and will
route them separately"
Link: https://lore.kernel.org/lkml/3779937.1619478404@warthog.procyon.org.uk/
* tag 'netfs-lib-20210426' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
netfs: Miscellaneous fixes
iov_iter: Four fixes for ITER_XARRAY
fscache, cachefiles: Add alternate API to use kiocb for read/write to cache
netfs: Add a tracepoint to log failures that would be otherwise unseen
netfs: Define an interface to talk to a cache
netfs: Add write_begin helper
netfs: Gather stats
netfs: Add tracepoints
netfs: Provide readahead and readpage netfs helpers
netfs, mm: Add set/end/wait_on_page_fscache() aliases
netfs, mm: Move PG_fscache helper funcs to linux/netfs.h
netfs: Documentation for helper library
netfs: Make a netfs helper module
mm: Implement readahead_control pageset expansion
mm/readahead: Handle ractl nr_pages being modified
fs: Document file_ra_state
mm/filemap: Pass the file_ra_state in the ractl
mm: Add set/end/wait functions for PG_private_2
iov_iter: Add ITER_XARRAY
Pull fileattr conversion updates from Miklos Szeredi via Al Viro:
"This splits the handling of FS_IOC_[GS]ETFLAGS from ->ioctl() into a
separate method.
The interface is reasonably uniform across the filesystems that
support it and gives nice boilerplate removal"
* 'miklos.fileattr' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (23 commits)
ovl: remove unneeded ioctls
fuse: convert to fileattr
fuse: add internal open/release helpers
fuse: unsigned open flags
fuse: move ioctl to separate source file
vfs: remove unused ioctl helpers
ubifs: convert to fileattr
reiserfs: convert to fileattr
ocfs2: convert to fileattr
nilfs2: convert to fileattr
jfs: convert to fileattr
hfsplus: convert to fileattr
efivars: convert to fileattr
xfs: convert to fileattr
orangefs: convert to fileattr
gfs2: convert to fileattr
f2fs: convert to fileattr
ext4: convert to fileattr
ext2: convert to fileattr
btrfs: convert to fileattr
...
User or developer may still be confused about why f2fs doesn't expose
compressed space to userspace, add description about compressed space
handling policy into f2fs documentation.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
There's a substantial amount of boilerplate in filesystems handling
FS_IOC_[GS]ETFLAGS/ FS_IOC_FS[GS]ETXATTR ioctls.
Also due to userspace buffers being involved in the ioctl API this is
difficult to stack, as shown by overlayfs issues related to these ioctls.
Introduce a new internal API named "fileattr" (fsxattr can be confused with
xattr, xflags is inappropriate, since this is more than just flags).
There's significant overlap between flags and xflags and this API handles
the conversions automatically, so filesystems may choose which one to use.
In ->fileattr_get() a hint is provided to the filesystem whether flags or
xattr are being requested by userspace, but in this series this hint is
ignored by all filesystems, since generating all the attributes is cheap.
If a filesystem doesn't implemement the fileattr API, just fall back to
f_op->ioctl(). When all filesystems are converted, the fallback can be
removed.
32bit compat ioctls are now handled by the generic code as well.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Commit a888db310195 ("ovl: fix regression with re-formatted lower
squashfs") attempted to fix a regression with existing setups that
use a practice that we are trying to discourage.
The discourage part was described this way in the commit message:
"To avoid the reported regression while still allowing the new features
with single lower squashfs, do not allow decoding origin with lower null
uuid unless user opted-in to one of the new features that require
following the lower inode of non-dir upper (index, xino, metacopy)."
The three mentioned features are disabled by default in Kconfig, so
it was assumed that if they are enabled, the user opted-in for them.
Apparently, distros started to configure CONFIG_OVERLAY_FS_XINO_AUTO=y
some time ago, so users upgrading their kernels can still be affected
by said regression even though they never opted-in for any new feature.
To fix this, treat "xino=on" as "user opted-in", but not "xino=auto".
Since we are changing the behavior of "xino=auto" to no longer follow
to lower origin with null uuid, take this one step further and disable
xino in that corner case. To be consistent, disable xino also in cases
of lower fs without file handle support and upper fs without xattr
support.
Update documentation w.r.t the new "xino=auto" behavior and fix the out
dated bits of documentation regarding "xino" and regarding offline
modifications to lower layers.
Link: https://lore.kernel.org/linux-unionfs/b36a429d7c563730c28d763d4d57a6fc30508a4f.1615216996.git.kevin@kevinlocke.name/
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Separate field in nameidata (nd->state) holding the flags that
should be internal-only - that way we both get some spare bits
in LOOKUP_... and get simpler rules for nd->root lifetime rules,
since we can set the replacement of LOOKUP_ROOT (ND_ROOT_PRESET)
at the same time we set nd->root.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
This adds support for encryption with casefolding.
Since the name on disk is case preserving, and also encrypted, we can no
longer just recompute the hash on the fly. Additionally, to avoid
leaking extra information from the hash of the unencrypted name, we use
siphash via an fscrypt v2 policy.
The hash is stored at the end of the directory entry for all entries
inside of an encrypted and casefolded directory apart from those that
deal with '.' and '..'. This way, the change is backwards compatible
with existing ext4 filesystems.
[ Changed to advertise this feature via the file:
/sys/fs/ext4/features/encrypted_casefold -- TYT ]
Signed-off-by: Daniel Rosenberg <drosen@google.com>
Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Link: https://lore.kernel.org/r/20210319073414.1381041-2-drosen@google.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
In this patch, we will add two new mount options: "gc_merge" and
"nogc_merge", when background_gc is on, "gc_merge" option can be
set to let background GC thread to handle foreground GC requests,
it can eliminate the sluggish issue caused by slow foreground GC
operation when GC is triggered from a process with limited I/O
and CPU resources.
Original idea is from Xiang.
Signed-off-by: Gao Xiang <xiang@kernel.org>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
We've missed a few documentation when adding new VM_* flags. Add the missing
pieces so they'll be in sync now.
Signed-off-by: Peter Xu <peterx@redhat.com>
Link: https://lore.kernel.org/r/20210302000646.432358-1-peterx@redhat.com
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
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>
Pull misc vfs updates from Al Viro:
"Assorted stuff pile - no common topic here"
* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
whack-a-mole: don't open-code iminor/imajor
9p: fix misuse of sscanf() in v9fs_stat2inode()
audit_alloc_mark(): don't open-code ERR_CAST()
fs/inode.c: make inode_init_always() initialize i_ino to 0
vfs: don't unnecessarily clone write access for writable fds
-----BEGIN PGP SIGNATURE-----
iQFDBAABCAAtFiEEIw+MvkEiF49krdp9F0NaE2wMflgFAmA5Qu8PHGNvcmJldEBs
d24ubmV0AAoJEBdDWhNsDH5Yiz0H/jTF+JcYstvGINx7jLZH4j9Pa4b/IZ3RO5uR
OpjkzhTNangk2pSS4nuoQGjDRz1miBRaY1yE923Wxk1T1Nk+DA6aYJbVTqpn962S
Z5IyQWzMIHFTAhSle0GeuTBk9Qx46ONhBJH1qsHCraAUtsQrxSUoF95ZftKD54gz
Eg+eFQscHen9on2ZlqypauZebVbAa3zq1JCyohK5URiXLXpNq7ASCcOZ6v1OJb76
thgxOQgb1/TQ+ZNEeRs8Bv5g6kcTlWhapIrnsYPrmCEYaj2ghvGbbSlWyAmJRPqT
PH+ucFCyjZqGcPmM5zerhVI+scQOLAJigAQa/B6HhRfmCyI1kkE=
=ZKHc
-----END PGP SIGNATURE-----
Merge tag 'docs-5.12-2' of git://git.lwn.net/linux
Pull documentation fixes from Jonathan Corbet:
"A handful of late-arriving documentation fixes, nothing all that
notable"
* tag 'docs-5.12-2' of git://git.lwn.net/linux:
docs: proc.rst: fix indentation warning
Documentation: cgroup-v2: fix path to example BPF program
docs: powerpc: Fix tables in syscall64-abi.rst
Documentation: features: refresh feature list
Documentation: features: remove c6x references
docs: ABI: testing: ima_policy: Fixed missing bracket
Fix unaesthetic indentation
scripts: kernel-doc: fix array element capture in pointer-to-func parsing
doc: use KCFLAGS instead of EXTRA_CFLAGS to pass flags from command line
Documentation: proc.rst: add more about the 6 fields in loadavg
Patch series "Fix some seq_file users that were recently broken".
A recent change to seq_file broke some users which were using seq_file
in a non-"standard" way ... though the "standard" isn't documented, so
they can be excused. The result is a possible leak - of memory in one
case, of references to a 'transport' in the other.
These three patches:
1/ document and explain the problem
2/ fix the problem user in x86
3/ fix the problem user in net/sctp
This patch (of 3):
Users of seq_file will sometimes find it convenient to take a resource,
such as a lock or memory allocation, in the ->start or ->next operations.
These are per-entry resources, distinct from per-session resources which
are taken in ->start and released in ->stop.
The preferred management of these is release the resource on the
subsequent call to ->next or ->stop.
However prior to Commit 1f4aace60b0e ("fs/seq_file.c: simplify seq_file
iteration code and interface") it happened that ->show would always be
called after ->start or ->next, and a few users chose to release the
resource in ->show.
This is no longer reliable. Since the mentioned commit, ->next will
always come after a successful ->show (to ensure m->index is updated
correctly), so the original ordering cannot be maintained.
This patch updates the documentation to clearly state the required
behaviour. Other patches will fix the few problematic users.
[akpm@linux-foundation.org: fix typo, per Willy]
Link: https://lkml.kernel.org/r/161248518659.21478.2484341937387294998.stgit@noble1
Link: https://lkml.kernel.org/r/161248539020.21478.3147971477400875336.stgit@noble1
Fixes: 1f4aace60b0e ("fs/seq_file.c: simplify seq_file iteration code and interface")
Signed-off-by: NeilBrown <neilb@suse.de>
Cc: Xin Long <lucien.xin@gmail.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Vlad Yasevich <vyasevich@gmail.com>
Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix indentation snafu in proc.rst as reported by Stephen.
next-20210219/Documentation/filesystems/proc.rst:697: WARNING: Unexpected indentation.
Fixes: 93ea4a0b8fce ("Documentation: proc.rst: add more about the 6 fields in loadavg")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Link: https://lore.kernel.org/r/20210223060418.21443-1-rdunlap@infradead.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCYCegywAKCRCRxhvAZXjc
ouJ6AQDlf+7jCQlQdeKKoN9QDFfMzG1ooemat36EpRRTONaGuAD8D9A4sUsG4+5f
4IU5Lj9oY4DEmF8HenbWK2ZHsesL2Qg=
=yPaw
-----END PGP SIGNATURE-----
Merge tag 'idmapped-mounts-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull idmapped mounts from Christian Brauner:
"This introduces idmapped mounts which has been in the making for some
time. Simply put, different mounts can expose the same file or
directory with different ownership. This initial implementation comes
with ports for fat, ext4 and with Christoph's port for xfs with more
filesystems being actively worked on by independent people and
maintainers.
Idmapping mounts handle a wide range of long standing use-cases. Here
are just a few:
- Idmapped mounts make it possible to easily share files between
multiple users or multiple machines especially in complex
scenarios. For example, idmapped mounts will be used in the
implementation of portable home directories in
systemd-homed.service(8) where they allow users to move their home
directory to an external storage device and use it on multiple
computers where they are assigned different uids and gids. This
effectively makes it possible to assign random uids and gids at
login time.
- It is possible to share files from the host with unprivileged
containers without having to change ownership permanently through
chown(2).
- It is possible to idmap a container's rootfs and without having to
mangle every file. For example, Chromebooks use it to share the
user's Download folder with their unprivileged containers in their
Linux subsystem.
- It is possible to share files between containers with
non-overlapping idmappings.
- Filesystem that lack a proper concept of ownership such as fat can
use idmapped mounts to implement discretionary access (DAC)
permission checking.
- They allow users to efficiently changing ownership on a per-mount
basis without having to (recursively) chown(2) all files. In
contrast to chown (2) changing ownership of large sets of files is
instantenous with idmapped mounts. This is especially useful when
ownership of a whole root filesystem of a virtual machine or
container is changed. With idmapped mounts a single syscall
mount_setattr syscall will be sufficient to change the ownership of
all files.
- Idmapped mounts always take the current ownership into account as
idmappings specify what a given uid or gid is supposed to be mapped
to. This contrasts with the chown(2) syscall which cannot by itself
take the current ownership of the files it changes into account. It
simply changes the ownership to the specified uid and gid. This is
especially problematic when recursively chown(2)ing a large set of
files which is commong with the aforementioned portable home
directory and container and vm scenario.
- Idmapped mounts allow to change ownership locally, restricting it
to specific mounts, and temporarily as the ownership changes only
apply as long as the mount exists.
Several userspace projects have either already put up patches and
pull-requests for this feature or will do so should you decide to pull
this:
- systemd: In a wide variety of scenarios but especially right away
in their implementation of portable home directories.
https://systemd.io/HOME_DIRECTORY/
- container runtimes: containerd, runC, LXD:To share data between
host and unprivileged containers, unprivileged and privileged
containers, etc. The pull request for idmapped mounts support in
containerd, the default Kubernetes runtime is already up for quite
a while now: https://github.com/containerd/containerd/pull/4734
- The virtio-fs developers and several users have expressed interest
in using this feature with virtual machines once virtio-fs is
ported.
- ChromeOS: Sharing host-directories with unprivileged containers.
I've tightly synced with all those projects and all of those listed
here have also expressed their need/desire for this feature on the
mailing list. For more info on how people use this there's a bunch of
talks about this too. Here's just two recent ones:
https://www.cncf.io/wp-content/uploads/2020/12/Rootless-Containers-in-Gitpod.pdfhttps://fosdem.org/2021/schedule/event/containers_idmap/
This comes with an extensive xfstests suite covering both ext4 and
xfs:
https://git.kernel.org/brauner/xfstests-dev/h/idmapped_mounts
It covers truncation, creation, opening, xattrs, vfscaps, setid
execution, setgid inheritance and more both with idmapped and
non-idmapped mounts. It already helped to discover an unrelated xfs
setgid inheritance bug which has since been fixed in mainline. It will
be sent for inclusion with the xfstests project should you decide to
merge this.
In order to support per-mount idmappings vfsmounts are marked with
user namespaces. The idmapping of the user namespace will be used to
map the ids of vfs objects when they are accessed through that mount.
By default all vfsmounts are marked with the initial user namespace.
The initial user namespace is used to indicate that a mount is not
idmapped. All operations behave as before and this is verified in the
testsuite.
Based on prior discussions we want to attach the whole user namespace
and not just a dedicated idmapping struct. This allows us to reuse all
the helpers that already exist for dealing with idmappings instead of
introducing a whole new range of helpers. In addition, if we decide in
the future that we are confident enough to enable unprivileged users
to setup idmapped mounts the permission checking can take into account
whether the caller is privileged in the user namespace the mount is
currently marked with.
The user namespace the mount will be marked with can be specified by
passing a file descriptor refering to the user namespace as an
argument to the new mount_setattr() syscall together with the new
MOUNT_ATTR_IDMAP flag. The system call follows the openat2() pattern
of extensibility.
The following conditions must be met in order to create an idmapped
mount:
- The caller must currently have the CAP_SYS_ADMIN capability in the
user namespace the underlying filesystem has been mounted in.
- The underlying filesystem must support idmapped mounts.
- The mount must not already be idmapped. This also implies that the
idmapping of a mount cannot be altered once it has been idmapped.
- The mount must be a detached/anonymous mount, i.e. it must have
been created by calling open_tree() with the OPEN_TREE_CLONE flag
and it must not already have been visible in the filesystem.
The last two points guarantee easier semantics for userspace and the
kernel and make the implementation significantly simpler.
By default vfsmounts are marked with the initial user namespace and no
behavioral or performance changes are observed.
The manpage with a detailed description can be found here:
1d7b902e28
In order to support idmapped mounts, filesystems need to be changed
and mark themselves with the FS_ALLOW_IDMAP flag in fs_flags. The
patches to convert individual filesystem are not very large or
complicated overall as can be seen from the included fat, ext4, and
xfs ports. Patches for other filesystems are actively worked on and
will be sent out separately. The xfstestsuite can be used to verify
that port has been done correctly.
The mount_setattr() syscall is motivated independent of the idmapped
mounts patches and it's been around since July 2019. One of the most
valuable features of the new mount api is the ability to perform
mounts based on file descriptors only.
Together with the lookup restrictions available in the openat2()
RESOLVE_* flag namespace which we added in v5.6 this is the first time
we are close to hardened and race-free (e.g. symlinks) mounting and
path resolution.
While userspace has started porting to the new mount api to mount
proper filesystems and create new bind-mounts it is currently not
possible to change mount options of an already existing bind mount in
the new mount api since the mount_setattr() syscall is missing.
With the addition of the mount_setattr() syscall we remove this last
restriction and userspace can now fully port to the new mount api,
covering every use-case the old mount api could. We also add the
crucial ability to recursively change mount options for a whole mount
tree, both removing and adding mount options at the same time. This
syscall has been requested multiple times by various people and
projects.
There is a simple tool available at
https://github.com/brauner/mount-idmapped
that allows to create idmapped mounts so people can play with this
patch series. I'll add support for the regular mount binary should you
decide to pull this in the following weeks:
Here's an example to a simple idmapped mount of another user's home
directory:
u1001@f2-vm:/$ sudo ./mount --idmap both:1000:1001:1 /home/ubuntu/ /mnt
u1001@f2-vm:/$ ls -al /home/ubuntu/
total 28
drwxr-xr-x 2 ubuntu ubuntu 4096 Oct 28 22:07 .
drwxr-xr-x 4 root root 4096 Oct 28 04:00 ..
-rw------- 1 ubuntu ubuntu 3154 Oct 28 22:12 .bash_history
-rw-r--r-- 1 ubuntu ubuntu 220 Feb 25 2020 .bash_logout
-rw-r--r-- 1 ubuntu ubuntu 3771 Feb 25 2020 .bashrc
-rw-r--r-- 1 ubuntu ubuntu 807 Feb 25 2020 .profile
-rw-r--r-- 1 ubuntu ubuntu 0 Oct 16 16:11 .sudo_as_admin_successful
-rw------- 1 ubuntu ubuntu 1144 Oct 28 00:43 .viminfo
u1001@f2-vm:/$ ls -al /mnt/
total 28
drwxr-xr-x 2 u1001 u1001 4096 Oct 28 22:07 .
drwxr-xr-x 29 root root 4096 Oct 28 22:01 ..
-rw------- 1 u1001 u1001 3154 Oct 28 22:12 .bash_history
-rw-r--r-- 1 u1001 u1001 220 Feb 25 2020 .bash_logout
-rw-r--r-- 1 u1001 u1001 3771 Feb 25 2020 .bashrc
-rw-r--r-- 1 u1001 u1001 807 Feb 25 2020 .profile
-rw-r--r-- 1 u1001 u1001 0 Oct 16 16:11 .sudo_as_admin_successful
-rw------- 1 u1001 u1001 1144 Oct 28 00:43 .viminfo
u1001@f2-vm:/$ touch /mnt/my-file
u1001@f2-vm:/$ setfacl -m u:1001:rwx /mnt/my-file
u1001@f2-vm:/$ sudo setcap -n 1001 cap_net_raw+ep /mnt/my-file
u1001@f2-vm:/$ ls -al /mnt/my-file
-rw-rwxr--+ 1 u1001 u1001 0 Oct 28 22:14 /mnt/my-file
u1001@f2-vm:/$ ls -al /home/ubuntu/my-file
-rw-rwxr--+ 1 ubuntu ubuntu 0 Oct 28 22:14 /home/ubuntu/my-file
u1001@f2-vm:/$ getfacl /mnt/my-file
getfacl: Removing leading '/' from absolute path names
# file: mnt/my-file
# owner: u1001
# group: u1001
user::rw-
user:u1001:rwx
group::rw-
mask::rwx
other::r--
u1001@f2-vm:/$ getfacl /home/ubuntu/my-file
getfacl: Removing leading '/' from absolute path names
# file: home/ubuntu/my-file
# owner: ubuntu
# group: ubuntu
user::rw-
user:ubuntu:rwx
group::rw-
mask::rwx
other::r--"
* tag 'idmapped-mounts-v5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux: (41 commits)
xfs: remove the possibly unused mp variable in xfs_file_compat_ioctl
xfs: support idmapped mounts
ext4: support idmapped mounts
fat: handle idmapped mounts
tests: add mount_setattr() selftests
fs: introduce MOUNT_ATTR_IDMAP
fs: add mount_setattr()
fs: add attr_flags_to_mnt_flags helper
fs: split out functions to hold writers
namespace: only take read lock in do_reconfigure_mnt()
mount: make {lock,unlock}_mount_hash() static
namespace: take lock_mount_hash() directly when changing flags
nfs: do not export idmapped mounts
overlayfs: do not mount on top of idmapped mounts
ecryptfs: do not mount on top of idmapped mounts
ima: handle idmapped mounts
apparmor: handle idmapped mounts
fs: make helpers idmap mount aware
exec: handle idmapped mounts
would_dump: handle idmapped mounts
...
-----BEGIN PGP SIGNATURE-----
iQEzBAABCAAdFiEEq1nRK9aeMoq1VSgcnJ2qBz9kQNkFAmAzoWUACgkQnJ2qBz9k
QNnFgQgAlng0JOzeCQvLpwweqFl0FCxYbOsZXC1xDyvfX3TiA6A6oiOR4tx3uhQN
cOQmJXaiMn4oCXjD1j6WZwGfy23yx0XchaoFK9jy2IqodaB/zUjkiWYYqt0G3XIX
ud35mxjLAGS12BCD0c+vHy2RMsUFl5ep+5aBHRHZJJhCcYbl7e5ctXZ3xB1Q0mgI
r639gD8JhH3ICdu9W0NaMvqOrVhJFNmhSGATKL/N96+oKub2x2ycYE4L2OXegxy3
mnFf26LjA8jt7K+KfHloTvkC6D4HVnnvKFvKiIbGKafiWhAE7q57ZO6BPCMajGue
3UHIhWGmwKXRU72+nW6N+089GbcO/g==
=1e+z
-----END PGP SIGNATURE-----
Merge tag 'lazytime_for_v5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs
Pull lazytime updates from Jan Kara:
"Cleanups of the lazytime handling in the writeback code making rules
for calling ->dirty_inode() filesystem handlers saner"
* tag 'lazytime_for_v5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
ext4: simplify i_state checks in __ext4_update_other_inode_time()
gfs2: don't worry about I_DIRTY_TIME in gfs2_fsync()
fs: improve comments for writeback_single_inode()
fs: drop redundant check from __writeback_single_inode()
fs: clean up __mark_inode_dirty() a bit
fs: pass only I_DIRTY_INODE flags to ->dirty_inode
fs: don't call ->dirty_inode for lazytime timestamp updates
fat: only specify I_DIRTY_TIME when needed in fat_update_time()
fs: only specify I_DIRTY_TIME when needed in generic_update_time()
fs: correctly document the inode dirty flags
Address Jon's feedback on the previous patch by adding info about
field separators in the /proc/loadavg file.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/r/20210222034729.22350-1-rdunlap@infradead.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
