Because we use a single work structure attached to the CIL rather
than the CIL context, we can only queue a single work item at a
time. This results in the CIL being single threaded and limits
performance when it becomes CPU bound.
The design of the CIL is that it is pipelined and multiple commits
can be running concurrently, but the way the work is currently
implemented means that it is not pipelining as it was intended. The
critical work to switch the CIL context can take a few milliseconds
to run, but the rest of the CIL context flush can take hundreds of
milliseconds to complete. The context switching is the serialisation
point of the CIL, once the context has been switched the rest of the
context push can run asynchrnously with all other context pushes.
Hence we can move the work to the CIL context so that we can run
multiple CIL pushes at the same time and spread the majority of
the work out over multiple CPUs. We can keep the per-cpu CIL commit
state on the CIL rather than the context, because the context is
pinned to the CIL until the switch is done and we aggregate and
drain the per-cpu state held on the CIL during the context switch.
However, because we no longer serialise the CIL work, we can have
effectively unlimited CIL pushes in progress. We don't want to do
this - not only does it create contention on the iclogs and the
state machine locks, we can run the log right out of space with
outstanding pushes. Instead, limit the work concurrency to 4
concurrent works being processed at a time. This is enough
concurrency to remove the CIL from being a CPU bound bottleneck but
not enough to create new contention points or unbound concurrency
issues.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
log->l_flags doesn't actually contain "flags" as such, it contains
operational state information that can change at runtime. For the
shutdown state, this at least should be an atomic bit because
it is read without holding locks in many places and so using atomic
bitops for the state field modifications makes sense.
This allows us to use things like test_and_set_bit() on state
changes (e.g. setting XLOG_TAIL_WARN) to avoid races in setting the
state when we aren't holding locks.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
These two features were merged a year ago, userspace tooling have been
merged, and no serious errors have been reported by the developers.
Drop the experimental tag to encourage wider testing.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Bill O'Donnell <billodo@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Now that we have the infrastructure to switch background workers on and
off at will, fix the block gc worker code so that we don't actually run
the worker when the filesystem is frozen, same as we do for deferred
inactivation.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Users have come to expect that the space accounting information in
statfs and getquota reports are fairly accurate. Now that we inactivate
inodes from a background queue, these numbers can be thrown off by
whatever resources are singly-owned by the inodes in the queue. Flush
the pending inactivations when userspace asks for a space usage report.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Move inode inactivation to background work contexts so that it no
longer runs in the context that releases the final reference to an
inode. This will allow process work that ends up blocking on
inactivation to continue doing work while the filesytem processes
the inactivation in the background.
A typical demonstration of this is unlinking an inode with lots of
extents. The extents are removed during inactivation, so this blocks
the process that unlinked the inode from the directory structure. By
moving the inactivation to the background process, the userspace
applicaiton can keep working (e.g. unlinking the next inode in the
directory) while the inactivation work on the previous inode is
done by a different CPU.
The implementation of the queue is relatively simple. We use a
per-cpu lockless linked list (llist) to queue inodes for
inactivation without requiring serialisation mechanisms, and a work
item to allow the queue to be processed by a CPU bound worker
thread. We also keep a count of the queue depth so that we can
trigger work after a number of deferred inactivations have been
queued.
The use of a bound workqueue with a single work depth allows the
workqueue to run one work item per CPU. We queue the work item on
the CPU we are currently running on, and so this essentially gives
us affine per-cpu worker threads for the per-cpu queues. THis
maintains the effective CPU affinity that occurs within XFS at the
AG level due to all objects in a directory being local to an AG.
Hence inactivation work tends to run on the same CPU that last
accessed all the objects that inactivation accesses and this
maintains hot CPU caches for unlink workloads.
A depth of 32 inodes was chosen to match the number of inodes in an
inode cluster buffer. This hopefully allows sequential
allocation/unlink behaviours to defering inactivation of all the
inodes in a single cluster buffer at a time, further helping
maintain hot CPU and buffer cache accesses while running
inactivations.
A hard per-cpu queue throttle of 256 inode has been set to avoid
runaway queuing when inodes that take a long to time inactivate are
being processed. For example, when unlinking inodes with large
numbers of extents that can take a lot of processing to free.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
[djwong: tweak comments and tracepoints, convert opflags to state bits]
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Move the xfs_inactive call and all the other debugging checks and stats
updates into xfs_inode_mark_reclaimable because most of that are
implementation details about the inode cache. This is preparation for
deferred inactivation that is coming up. We also move it around
xfs_icache.c in preparation for deferred inactivation.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
The inode inactivation and CIL tracking percpu structures are
per-xfs_mount structures. That means when we get a CPU dead
notification, we need to then iterate all the per-cpu structure
instances to process them. Rather than keeping linked lists of
per-cpu structures in each subsystem, add a list of all xfs_mounts
that the generic xfs_cpu_dead() function will iterate and call into
each subsystem appropriately.
This allows us to handle both per-mount and global XFS percpu state
from xfs_cpu_dead(), and avoids the need to link subsystem
structures that can be easily found from the xfs_mount into their
own global lists.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
[djwong: expand some comments about mount list setup ordering rules]
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
We need to move to per-cpu state for both deferred inode
inactivation and CIL tracking, but to do that we
need to handle CPUs being removed from the system by the hot-plug
code. Introduce generic XFS infrastructure to handle CPU hotplug
events that is set up at module init time and torn down at module
exit time.
Initially, we only need CPU dead notifications, so we only set
up a callback for these notifications. The infrastructure can be
updated in future for other CPU hotplug state machine notifications
easily if ever needed.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
[djwong: rearrange some macros, fix function prototypes]
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
These only made a difference when quotaoff supported disabling quota
accounting on a mounted file system, so we can switch everyone to use
a single set of flags and helpers now. Note that the *QUOTA_ON naming
for the helpers is kept as it was the much more commonly used one.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
It's a one line wrapper around blkdev_issue_flush(). Just replace it
with direct calls to blkdev_issue_flush().
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Chandan Babu R <chandanrlinux@gmail.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
This ambitious series aims to cleans up redundant inode walk code in
xfs_icache.c, hide implementation details of the quotaoff dquot release
code, and eliminates indirect function calls from incore inode walks.
The first thing it does is to move all the code that quotaoff calls to
release dquots from all incore inodes into xfs_icache.c. Next, it
separates the goal of an inode walk from the actual radix tree tags that
may or may not be involved and drops the kludgy XFS_ICI_NO_TAG thing.
Finally, we split the speculative preallocation (blockgc) and quotaoff
dquot release code paths into separate functions so that we can keep the
implementations cohesive.
Christoph suggested last cycle that we 'simply' change quotaoff not to
allow deactivating quota entirely, but as these cleanups are to enable
one major change in behavior (deferred inode inactivation) I do not want
to add a second behavior change (quotaoff) as a dependency.
To be blunt: Additional cleanups are not in scope for this series.
Next, I made two observations about incore inode radix tree walks --
since there's a 1:1 mapping between the walk goal and the per-inode
processing function passed in, we can use the goal to make a direct call
to the processing function. Furthermore, the only caller to supply a
nonzero iter_flags argument is quotaoff, and there's only one INEW flag.
From that observation, I concluded that it's quite possible to remove
two parameters from the xfs_inode_walk* function signatures -- the
iter_flags, and the execute function pointer. The middle of the series
moves the INEW functionality into the one piece (quotaoff) that wants
it, and removes the indirect calls.
The final observation is that the inode reclaim walk loop is now almost
the same as xfs_inode_walk, so it's silly to maintain two copies. Merge
the reclaim loop code into xfs_inode_walk.
Lastly, refactor the per-ag radix tagging functions since there's
duplicated code that can be consolidated.
This series is a prerequisite for the next two patchsets, since deferred
inode inactivation will add another inode radix tree tag and iterator
function to xfs_inode_walk.
v2: walk the vfs inode list when running quotaoff instead of the radix
tree, then rework the (now completely internal) inode walk function
to take the tag as the main parameter.
v3: merge the reclaim loop into xfs_inode_walk, then consolidate the
radix tree tagging functions
v4: rebase to 5.13-rc4
v5: combine with the quotaoff patchset, reorder functions to minimize
forward declarations, split inode walk goals from radix tree tags
to reduce conceptual confusion
v6: start moving the inode cache code towards the xfs_icwalk prefix
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Merge tag 'inode-walk-cleanups-5.14_2021-06-03' of https://git.kernel.org/pub/scm/linux/kernel/git/djwong/xfs-linux into xfs-5.14-merge2
xfs: clean up incore inode walk functions
This ambitious series aims to cleans up redundant inode walk code in
xfs_icache.c, hide implementation details of the quotaoff dquot release
code, and eliminates indirect function calls from incore inode walks.
The first thing it does is to move all the code that quotaoff calls to
release dquots from all incore inodes into xfs_icache.c. Next, it
separates the goal of an inode walk from the actual radix tree tags that
may or may not be involved and drops the kludgy XFS_ICI_NO_TAG thing.
Finally, we split the speculative preallocation (blockgc) and quotaoff
dquot release code paths into separate functions so that we can keep the
implementations cohesive.
Christoph suggested last cycle that we 'simply' change quotaoff not to
allow deactivating quota entirely, but as these cleanups are to enable
one major change in behavior (deferred inode inactivation) I do not want
to add a second behavior change (quotaoff) as a dependency.
To be blunt: Additional cleanups are not in scope for this series.
Next, I made two observations about incore inode radix tree walks --
since there's a 1:1 mapping between the walk goal and the per-inode
processing function passed in, we can use the goal to make a direct call
to the processing function. Furthermore, the only caller to supply a
nonzero iter_flags argument is quotaoff, and there's only one INEW flag.
From that observation, I concluded that it's quite possible to remove
two parameters from the xfs_inode_walk* function signatures -- the
iter_flags, and the execute function pointer. The middle of the series
moves the INEW functionality into the one piece (quotaoff) that wants
it, and removes the indirect calls.
The final observation is that the inode reclaim walk loop is now almost
the same as xfs_inode_walk, so it's silly to maintain two copies. Merge
the reclaim loop code into xfs_inode_walk.
Lastly, refactor the per-ag radix tagging functions since there's
duplicated code that can be consolidated.
This series is a prerequisite for the next two patchsets, since deferred
inode inactivation will add another inode radix tree tag and iterator
function to xfs_inode_walk.
v2: walk the vfs inode list when running quotaoff instead of the radix
tree, then rework the (now completely internal) inode walk function
to take the tag as the main parameter.
v3: merge the reclaim loop into xfs_inode_walk, then consolidate the
radix tree tagging functions
v4: rebase to 5.13-rc4
v5: combine with the quotaoff patchset, reorder functions to minimize
forward declarations, split inode walk goals from radix tree tags
to reduce conceptual confusion
v6: start moving the inode cache code towards the xfs_icwalk prefix
* tag 'inode-walk-cleanups-5.14_2021-06-03' of https://git.kernel.org/pub/scm/linux/kernel/git/djwong/xfs-linux:
xfs: refactor per-AG inode tagging functions
xfs: merge xfs_reclaim_inodes_ag into xfs_inode_walk_ag
xfs: pass struct xfs_eofblocks to the inode scan callback
xfs: fix radix tree tag signs
xfs: make the icwalk processing functions clean up the grab state
xfs: clean up inode state flag tests in xfs_blockgc_igrab
xfs: remove indirect calls from xfs_inode_walk{,_ag}
xfs: remove iter_flags parameter from xfs_inode_walk_*
xfs: move xfs_inew_wait call into xfs_dqrele_inode
xfs: separate the dqrele_all inode grab logic from xfs_inode_walk_ag_grab
xfs: pass the goal of the incore inode walk to xfs_inode_walk()
xfs: rename xfs_inode_walk functions to xfs_icwalk
xfs: move the inode walk functions further down
xfs: detach inode dquots at the end of inactivation
xfs: move the quotaoff dqrele inode walk into xfs_icache.c
[djwong: added variable names to function declarations while fixing
merge conflicts]
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
In preparation for adding another incore inode tree tag, refactor the
code that sets and clears tags from the per-AG inode tree and the tree
of per-AG structures, and remove the open-coded versions used by the
blockgc code.
Note: For reclaim, we now rely on the radix tree tags instead of the
reclaimable inode count more heavily than we used to. The conversion
should be fine, but the logic isn't 100% identical.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
They are AG functions, not superblock functions, so move them to the
appropriate location.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
In preparation of removing the historic icinode struct, move the flags
field into the containing xfs_inode structure.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Removal of kmem_zone_init wrappers accidentally changed a slab cache
name from "xfs_trans" to "xf_trans". Fix this so that userspace
consumers of /proc/slabinfo and /sys/kernel/slab can find it again.
Fixes: b1231760e4 ("xfs: Remove slab init wrappers")
Signed-off-by: Anthony Iliopoulos <ailiop@suse.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Skip the warnings about mount option being deprecated if we are
remounting and deprecated option state is not changing.
Bug: https://bugzilla.kernel.org/show_bug.cgi?id=211605
Fix-suggested-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Pavel Reichl <preichl@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Rename mp variable to parsisng_mp so it is easy to distinguish
between current mount point handle and handle for mount point
which mount options are being parsed.
Suggested-by: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: Pavel Reichl <preichl@redhat.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Carlos Maiolino <cmaiolino@redhat.com>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Since we're about to start using the blockgc workqueue to dispose of
inactivated inodes, strip the "block" prefix from the name; now it's
merely the general garbage collection (gc) workqueue.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
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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
...
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Merge tag 'for-5.12/block-2021-02-17' of git://git.kernel.dk/linux-block
Pull core block updates from Jens Axboe:
"Another nice round of removing more code than what is added, mostly
due to Christoph's relentless pursuit of tech debt removal/cleanups.
This pull request contains:
- Two series of BFQ improvements (Paolo, Jan, Jia)
- Block iov_iter improvements (Pavel)
- bsg error path fix (Pan)
- blk-mq scheduler improvements (Jan)
- -EBUSY discard fix (Jan)
- bvec allocation improvements (Ming, Christoph)
- bio allocation and init improvements (Christoph)
- Store bdev pointer in bio instead of gendisk + partno (Christoph)
- Block trace point cleanups (Christoph)
- hard read-only vs read-only split (Christoph)
- Block based swap cleanups (Christoph)
- Zoned write granularity support (Damien)
- Various fixes/tweaks (Chunguang, Guoqing, Lei, Lukas, Huhai)"
* tag 'for-5.12/block-2021-02-17' of git://git.kernel.dk/linux-block: (104 commits)
mm: simplify swapdev_block
sd_zbc: clear zone resources for non-zoned case
block: introduce blk_queue_clear_zone_settings()
zonefs: use zone write granularity as block size
block: introduce zone_write_granularity limit
block: use blk_queue_set_zoned in add_partition()
nullb: use blk_queue_set_zoned() to setup zoned devices
nvme: cleanup zone information initialization
block: document zone_append_max_bytes attribute
block: use bi_max_vecs to find the bvec pool
md/raid10: remove dead code in reshape_request
block: mark the bio as cloned in bio_iov_bvec_set
block: set BIO_NO_PAGE_REF in bio_iov_bvec_set
block: remove a layer of indentation in bio_iov_iter_get_pages
block: turn the nr_iovecs argument to bio_alloc* into an unsigned short
block: remove the 1 and 4 vec bvec_slabs entries
block: streamline bvec_alloc
block: factor out a bvec_alloc_gfp helper
block: move struct biovec_slab to bio.c
block: reuse BIO_INLINE_VECS for integrity bvecs
...
Expose the workqueue sysfs knobs for the speculative preallocation gc
workers on all kernels, and update the sysadmin information.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Split the block preallocation garbage collection work into per-AG work
items so that we can take advantage of parallelization.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Shorten the names of the two functions that start and stop block
preallocation garbage collection and move them up to the other blockgc
functions.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Remove the separate cowblocks work items and knob so that we can control
and run everything from a single blockgc work queue. Note that the
speculative_prealloc_lifetime sysfs knob retains its historical name
even though the functions move to prefix xfs_blockgc_*.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Change the one remaining caller of xfs_icache_free_cowblocks to use our
new combined blockgc scan function instead, since we will soon be
combining the two scans. This introduces a slight behavior change,
since a readonly remount now clears out post-EOF preallocations and not
just CoW staging extents.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
When CONFIG_XFS_DEBUG=y, set WQ_SYSFS on all workqueues that we create
so that we (developers) have a means to monitor cpu affinity and whatnot
for background workers. In the next patchset we'll expose knobs for
more of the workqueues publicly and document it, but not now.
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
There is no point in allocating memory for a synchronous flush.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Acked-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Enable idmapped mounts for xfs. This basically just means passing down
the user_namespace argument from the VFS methods down to where it is
passed to the relevant helpers.
Note that full-filesystem bulkstat is not supported from inside idmapped
mounts as it is an administrative operation that acts on the whole file
system. The limitation is not applied to the bulkstat single operation
that just operates on a single inode.
Link: https://lore.kernel.org/r/20210121131959.646623-40-christian.brauner@ubuntu.com
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Filesystem freeze cleans the log and immediately redirties it so log
recovery runs if a crash occurs after the filesystem is frozen. Now
that log quiesce covers the log, there is no need to clean the log and
redirty it to trigger log recovery because covering has the same
effect. Update xfs_fs_freeze() to quiesce (and thus cover) the log.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
xfs_quiesce_attr() is now a wrapper for xfs_log_clean(). Remove it
and call xfs_log_clean() directly.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
These two calls are repeated at the beginning of xfs_log_quiesce().
Drop them from xfs_quiesce_attr().
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
xfs_log_sbcount() calls xfs_sync_sb() to sync superblock counters to
disk when lazy superblock accounting is enabled. This occurs on
unmount, freeze, and read-only (re)mount and ensures the final
values are calculated and persisted to disk before each form of
quiesce completes.
Now that log covering occurs in all of these contexts and uses the
same xfs_sync_sb() mechanism to update log state, there is no need
to log the superblock separately for any reason. Update the log
quiesce path to sync the superblock at least once for any mount
where lazy superblock accounting is enabled. If the log is already
covered, it will remain in the covered state. Otherwise, the next
sync as part of the normal covering sequence will carry the
associated superblock update with it. Remove xfs_log_sbcount() now
that it is no longer needed.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Log quiesce is currently associated with cleaning the log, which is
accomplished by writing an unmount record as the last step of the
quiesce sequence. The quiesce codepath is a bit convoluted in this
regard due to how it is reused from various contexts. In preparation
to create separate log cleaning and log covering interfaces, lift
the write of the unmount record into a new cleaning helper and call
that wherever xfs_log_quiesce() is currently invoked. No functional
changes.
Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Allison Henderson <allison.henderson@oracle.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
The quota option 'usrquota' should be shown if both the XFS_UQUOTA_ACCT
and XFS_UQUOTA_ENFD flags are set. The option 'uqnoenforce' should be
shown when only the XFS_UQUOTA_ACCT flag is set. The current code logic
seems wrong, Fix it and show proper options.
Signed-off-by: Kaixu Xia <kaixuxia@tencent.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Get rid of this one-off namespace since we're done converting things to
fscontext now.
Suggested-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Refactor all the open-coded validation of file block ranges into a
single helper, and teach the bmap scrubber to check the ranges.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Define an incompat feature flag to indicate that the filesystem needs to
be repaired. While libxfs will recognize this feature, the kernel will
refuse to mount if the feature flag is set, and only xfs_repair will be
able to clear the flag. The goal here is to force the admin to run
xfs_repair to completion after upgrading the filesystem, or if we
otherwise detect anomalies.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
A couple of the superblock validation checks apply only to the kernel,
so move them to xfs_fc_fill_super before we add the needsrepair "feature",
which will prevent the kernel (but not xfsprogs) from mounting the
filesystem. This also reduces the diff between kernel and userspace
libxfs.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Pull misc vfs updates from Al Viro:
"Assorted stuff all over the place (the largest group here is
Christoph's stat cleanups)"
* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
fs: remove KSTAT_QUERY_FLAGS
fs: remove vfs_stat_set_lookup_flags
fs: move vfs_fstatat out of line
fs: implement vfs_stat and vfs_lstat in terms of vfs_fstatat
fs: remove vfs_statx_fd
fs: omfs: use kmemdup() rather than kmalloc+memcpy
[PATCH] reduce boilerplate in fsid handling
fs: Remove duplicated flag O_NDELAY occurring twice in VALID_OPEN_FLAGS
selftests: mount: add nosymfollow tests
Add a "nosymfollow" mount option.
ikeep/noikeep was a workaround for old DMAPI code which is no longer
relevant.
attr2/noattr2 - is for controlling upgrade behaviour from fixed attribute
fork sizes in the inode (attr1) and dynamic attribute fork sizes (attr2).
mkfs has defaulted to setting attr2 since 2007, hence just about every
XFS filesystem out there in production right now uses attr2.
Signed-off-by: Pavel Reichl <preichl@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
[darrick: fix minor typos]
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
The V4 filesystem format contains known weaknesses in the on-disk format
that make metadata verification diffiult. In addition, the format does
not support dates past 2038 and will not be upgraded to do so. We
should start the process of retiring the old format to close off attack
surfaces and to encourage users to migrate onto V5.
Therefore, make XFS V4 support a configurable option. For the first
period it will be default Y in case some distributors want to withdraw
support early; for the second period it will be default N so that anyone
who wishes to continue support can do so; and after that, support will
be removed from the kernel. Dates for these events have been added to
the upstream kernel.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Eric Sandeen <sandeen@redhat.com>
Add a couple of tracepoints so that we can check the timestamp limits
being set on inodes and quotas.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Allison Collins <allison.henderson@oracle.com>
Reviewed-by: Gao Xiang <hsiangkao@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Redesign the ondisk inode timestamps to be a simple unsigned 64-bit
counter of nanoseconds since 14 Dec 1901 (i.e. the minimum time in the
32-bit unix time epoch). This enables us to handle dates up to 2486,
which solves the y2038 problem.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Gao Xiang <hsiangkao@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Formally define the inode timestamp ranges that existing filesystems
support, and switch the vfs timetamp ranges to use it.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Allison Collins <allison.henderson@oracle.com>
Reviewed-by: Gao Xiang <hsiangkao@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Add a btree block usage counters for both inode btrees to the AGI header
so that we don't have to walk the entire finobt at mount time to create
the per-AG reservations.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
With the recent rework of the inode cluster flushing, we no longer
ever wait on the the inode flush "lock". It was never a lock in the
first place, just a completion to allow callers to wait for inode IO
to complete. We now never wait for flush completion as all inode
flushing is non-blocking. Hence we can get rid of all the iflock
infrastructure and instead just set and check a state flag.
Rename the XFS_IFLOCK flag to XFS_IFLUSHING, convert all the
xfs_iflock_nowait() test-and-set operations on that flag, and
replace all the xfs_ifunlock() calls to clear operations.
Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
The MS_I_VERSION mount flag is exposed via the VFS, as documented
in the mount manpages etc; see the iversion and noiversion mount
options in mount(8).
As a result, mount -o remount looks for this option in /proc/mounts
and will only send the I_VERSION flag back in during remount it it
is present. Since it's not there, a remount will /remove/ the
I_VERSION flag at the vfs level, and iversion functionality is lost.
xfs v5 superblocks intend to always have i_version enabled; it is
set as a default at mount time, but is lost during remount for the
reasons above.
The generic fix would be to expose this documented option in
/proc/mounts, but since that was rejected, fix it up again in the
xfs remount path instead, so that at least xfs won't suffer from
this misbehavior.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Depending on the workloads, the following circular locking dependency
warning between sb_internal (a percpu rwsem) and fs_reclaim (a pseudo
lock) may show up:
======================================================
WARNING: possible circular locking dependency detected
5.0.0-rc1+ #60 Tainted: G W
------------------------------------------------------
fsfreeze/4346 is trying to acquire lock:
0000000026f1d784 (fs_reclaim){+.+.}, at:
fs_reclaim_acquire.part.19+0x5/0x30
but task is already holding lock:
0000000072bfc54b (sb_internal){++++}, at: percpu_down_write+0xb4/0x650
which lock already depends on the new lock.
:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(sb_internal);
lock(fs_reclaim);
lock(sb_internal);
lock(fs_reclaim);
*** DEADLOCK ***
4 locks held by fsfreeze/4346:
#0: 00000000b478ef56 (sb_writers#8){++++}, at: percpu_down_write+0xb4/0x650
#1: 000000001ec487a9 (&type->s_umount_key#28){++++}, at: freeze_super+0xda/0x290
#2: 000000003edbd5a0 (sb_pagefaults){++++}, at: percpu_down_write+0xb4/0x650
#3: 0000000072bfc54b (sb_internal){++++}, at: percpu_down_write+0xb4/0x650
stack backtrace:
Call Trace:
dump_stack+0xe0/0x19a
print_circular_bug.isra.10.cold.34+0x2f4/0x435
check_prev_add.constprop.19+0xca1/0x15f0
validate_chain.isra.14+0x11af/0x3b50
__lock_acquire+0x728/0x1200
lock_acquire+0x269/0x5a0
fs_reclaim_acquire.part.19+0x29/0x30
fs_reclaim_acquire+0x19/0x20
kmem_cache_alloc+0x3e/0x3f0
kmem_zone_alloc+0x79/0x150
xfs_trans_alloc+0xfa/0x9d0
xfs_sync_sb+0x86/0x170
xfs_log_sbcount+0x10f/0x140
xfs_quiesce_attr+0x134/0x270
xfs_fs_freeze+0x4a/0x70
freeze_super+0x1af/0x290
do_vfs_ioctl+0xedc/0x16c0
ksys_ioctl+0x41/0x80
__x64_sys_ioctl+0x73/0xa9
do_syscall_64+0x18f/0xd23
entry_SYSCALL_64_after_hwframe+0x49/0xbe
This is a false positive as all the dirty pages are flushed out before
the filesystem can be frozen.
One way to avoid this splat is to add GFP_NOFS to the affected allocation
calls by using the memalloc_nofs_save()/memalloc_nofs_restore() pair.
This shouldn't matter unless the system is really running out of memory.
In that particular case, the filesystem freeze operation may fail while
it was succeeding previously.
Without this patch, the command sequence below will show that the lock
dependency chain sb_internal -> fs_reclaim exists.
# fsfreeze -f /home
# fsfreeze --unfreeze /home
# grep -i fs_reclaim -C 3 /proc/lockdep_chains | grep -C 5 sb_internal
After applying the patch, such sb_internal -> fs_reclaim lock dependency
chain can no longer be found. Because of that, the locking dependency
warning will not be shown.
Suggested-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Waiman Long <longman@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
