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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
...
Testing with the fscache overhaul has triggered some lockdep warnings
about circular lock dependencies involving page_mkwrite and the
mmap_lock. It'd be better to do the "real work" without the mmap lock
being held.
Change the skip_checking_caps parameter in __ceph_put_cap_refs to an
enum, and use that to determine whether to queue check_caps, do it
synchronously or not at all. Change ceph_page_mkwrite to do a
ceph_put_cap_refs_async().
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Add a generic function for taking an inode reference, setting the I_WORK
bit and queueing i_work. Turn the ceph_queue_* functions into static
inline wrappers that pass in the right bit.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Extend some inode methods with an additional user namespace argument. A
filesystem that is aware of idmapped mounts will receive the user
namespace the mount has been marked with. This can be used for
additional permission checking and also to enable filesystems to
translate between uids and gids if they need to. We have implemented all
relevant helpers in earlier patches.
As requested we simply extend the exisiting inode method instead of
introducing new ones. This is a little more code churn but it's mostly
mechanical and doesnt't leave us with additional inode methods.
Link: https://lore.kernel.org/r/20210121131959.646623-25-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
The generic_fillattr() helper fills in the basic attributes associated
with an inode. Enable it to handle idmapped mounts. If the inode is
accessed through an idmapped mount map it into the mount's user
namespace before we store the uid and gid. If the initial user namespace
is passed nothing changes so non-idmapped mounts will see identical
behavior as before.
Link: https://lore.kernel.org/r/20210121131959.646623-12-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
The posix acl permission checking helpers determine whether a caller is
privileged over an inode according to the acls associated with the
inode. Add helpers that make it possible to handle acls on idmapped
mounts.
The vfs and the filesystems targeted by this first iteration make use of
posix_acl_fix_xattr_from_user() and posix_acl_fix_xattr_to_user() to
translate basic posix access and default permissions such as the
ACL_USER and ACL_GROUP type according to the initial user namespace (or
the superblock's user namespace) to and from the caller's current user
namespace. Adapt these two helpers to handle idmapped mounts whereby we
either map from or into the mount's user namespace depending on in which
direction we're translating.
Similarly, cap_convert_nscap() is used by the vfs to translate user
namespace and non-user namespace aware filesystem capabilities from the
superblock's user namespace to the caller's user namespace. Enable it to
handle idmapped mounts by accounting for the mount's user namespace.
In addition the fileystems targeted in the first iteration of this patch
series make use of the posix_acl_chmod() and, posix_acl_update_mode()
helpers. Both helpers perform permission checks on the target inode. Let
them handle idmapped mounts. These two helpers are called when posix
acls are set by the respective filesystems to handle this case we extend
the ->set() method to take an additional user namespace argument to pass
the mount's user namespace down.
Link: https://lore.kernel.org/r/20210121131959.646623-9-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
When file attributes are changed most filesystems rely on the
setattr_prepare(), setattr_copy(), and notify_change() helpers for
initialization and permission checking. Let them handle idmapped mounts.
If the inode is accessed through an idmapped mount map it into the
mount's user namespace. Afterwards the checks are identical to
non-idmapped mounts. If the initial user namespace is passed nothing
changes so non-idmapped mounts will see identical behavior as before.
Helpers that perform checks on the ia_uid and ia_gid fields in struct
iattr assume that ia_uid and ia_gid are intended values and have already
been mapped correctly at the userspace-kernelspace boundary as we
already do today. If the initial user namespace is passed nothing
changes so non-idmapped mounts will see identical behavior as before.
Link: https://lore.kernel.org/r/20210121131959.646623-8-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
The two helpers inode_permission() and generic_permission() are used by
the vfs to perform basic permission checking by verifying that the
caller is privileged over an inode. In order to handle idmapped mounts
we extend the two helpers with an additional user namespace argument.
On idmapped mounts the two helpers will make sure to map the inode
according to the mount's user namespace and then peform identical
permission checks to inode_permission() and generic_permission(). If the
initial user namespace is passed nothing changes so non-idmapped mounts
will see identical behavior as before.
Link: https://lore.kernel.org/r/20210121131959.646623-6-christian.brauner@ubuntu.com
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Acked-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
We already have a pointer to the argument struct in req->r_args. Use that
instead of groveling around in the ceph_mds_request_head.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Geng Jichao reported a rather complex deadlock involving several
moving parts:
1) readahead is issued against an inode and some of its pages are locked
while the read is in flight
2) the same inode is evicted from the cache, and this task gets stuck
waiting for the page lock because of the above readahead
3) another task is processing a reply trace, and looks up the inode
being evicted while holding the s_mutex. That ends up waiting for the
eviction to complete
4) a write reply for an unrelated inode is then processed in the
ceph_con_workfn job. It calls ceph_check_caps after putting wrbuffer
caps, and that gets stuck waiting on the s_mutex held by 3.
The reply to "1" is stuck behind the write reply in "4", so we deadlock
at that point.
This patch changes the trace processing to call ceph_get_inode outside
of the s_mutex and snap_rwsem, which should break the cycle above.
[ idryomov: break unnecessarily long lines ]
URL: https://tracker.ceph.com/issues/47998
Reported-by: Geng Jichao <gengjichao@jd.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Luis Henriques <lhenriques@suse.de>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
The link count for a directory is defined as inode->i_subdirs + 2,
(for "." and ".."). i_subdirs is only populated when Fs caps are held.
Ensure we grab Fs caps when fetching the link count for a directory.
[ idryomov: break unnecessarily long line ]
URL: https://tracker.ceph.com/issues/48125
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
When recovering a session (a'la recover_session=clean), we want to do
all of the operations that we do on a forced umount, but changing the
mount state to SHUTDOWN is can cause queued MDS requests to fail when
the session comes back. Most of those can idle until the session is
recovered in this situation.
Reserve SHUTDOWN state for forced umount, and make a new RECOVER state
for the forced reconnect situation. Change several tests for equality with
SHUTDOWN to test for that or RECOVER.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
In client for each inode, it may have many opened files and may
have been pinned in more than one MDS servers. And some inodes
are idle, which have no any opened files.
This patch will show these metrics in the debugfs, likes:
item total
-----------------------------------------
opened files / total inodes 14 / 5
pinned i_caps / total inodes 7 / 5
opened inodes / total inodes 3 / 5
Will send these metrics to ceph, which will be used by the `fs top`,
later.
[ jlayton: drop unrelated hunk, count hashed inodes instead of
allocated ones ]
URL: https://tracker.ceph.com/issues/47005
Signed-off-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
This will help simplify the code.
[ jlayton: fix minor merge conflict in quota.c ]
Signed-off-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Tuan and Ulrich mentioned that they were hitting a problem on s390x,
which has a 32-bit ino_t value, even though it's a 64-bit arch (for
historical reasons).
I think the current handling of inode numbers in the ceph driver is
wrong. It tries to use 32-bit inode numbers on 32-bit arches, but that's
actually not a problem. 32-bit arches can deal with 64-bit inode numbers
just fine when userland code is compiled with LFS support (the common
case these days).
What we really want to do is just use 64-bit numbers everywhere, unless
someone has mounted with the ino32 mount option. In that case, we want
to ensure that we hash the inode number down to something that will fit
in 32 bits before presenting the value to userland.
Add new helper functions that do this, and only do the conversion before
presenting these values to userland in getattr and readdir.
The inode table hashvalue is changed to just cast the inode number to
unsigned long, as low-order bits are the most likely to vary anyway.
While it's not strictly required, we do want to put something in
inode->i_ino. Instead of basing it on BITS_PER_LONG, however, base it on
the size of the ino_t type.
NOTE: This is a user-visible change on 32-bit arches:
1/ inode numbers will be seen to have changed between kernel versions.
32-bit arches will see large inode numbers now instead of the hashed
ones they saw before.
2/ any really old software not built with LFS support may start failing
stat() calls with -EOVERFLOW on inode numbers >2^32. Nothing much we
can do about these, but hopefully the intersection of people running
such code on ceph will be very small.
The workaround for both problems is to mount with "-o ino32".
[ idryomov: changelog tweak ]
URL: https://tracker.ceph.com/issues/46828
Reported-by: Ulrich Weigand <Ulrich.Weigand@de.ibm.com>
Reported-and-Tested-by: Tuan Hoang1 <Tuan.Hoang1@ibm.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Count hits and misses in the caps cache. If the client has all of
the necessary caps when a task needs references, then it's counted
as a hit. Any other situation is a miss.
URL: https://tracker.ceph.com/issues/43215
Signed-off-by: Xiubo Li <xiubli@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
The .snap directory timestamps are kept at 0 (1970-01-01 00:00), which
isn't consistent with what the fuse client does. This patch makes the
behaviour consistent, by setting these timestamps (atime, btime, ctime,
mtime) to those of the parent directory.
Cc: Marc Roos <M.Roos@f1-outsourcing.eu>
Signed-off-by: Luis Henriques <lhenriques@suse.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
If an inode has caps from multiple mds's, the following can happen:
- non-auth mds revokes Fsc. Fcb is used, so page writeback is queued.
- when writeback finishes, ceph_check_caps() is called with auth only
flag. ceph_check_caps() invalidates pagecache, but skips checking any
non-auth caps.
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Originally, calling ceph_get_fmode() for open files is by thread that
handles request reply. There is a small window between updating caps and
and waking the request initiator. We need to prevent ceph_check_caps()
from releasing wanted caps in the window.
Previous patches made fill_inode() call __ceph_touch_fmode() for open file
requests. This prevented ceph_check_caps() from releasing wanted caps for
'caps_wanted_delay_min' seconds, enough for request initiator to get
woken up and call ceph_get_fmode().
This allows us to now call ceph_get_fmode() in ceph_open() instead.
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
__ceph_caps_file_wanted() already checks 'caps_wanted_delay_min' and
'caps_wanted_delay_max'. There is no need to duplicate the logic in
ceph_check_caps() and __send_cap()
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Add i_last_rd and i_last_wr to ceph_inode_info. These fields are
used to track the last time the client acquired read/write caps for
the inode.
If there is no read/write on an inode for 'caps_wanted_delay_max'
seconds, __ceph_caps_file_wanted() does not request caps for read/write
even there are open files.
Call __ceph_touch_fmode() for dir operations. __ceph_caps_file_wanted()
calculates dir's wanted caps according to last dir read/modification. If
there is recent dir read, dir inode wants CEPH_CAP_ANY_SHARED caps. If
there is recent dir modification, also wants CEPH_CAP_FILE_EXCL.
Readdir is a special case. Dir inode wants CEPH_CAP_FILE_EXCL after
readdir, as with that, modifications do not need to release
CEPH_CAP_FILE_SHARED or invalidate all dentry leases issued by readdir.
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
If a create is done, then typically we'll end up writing to the file
soon afterward. We don't want to wait for the reply before doing that
when doing an async create, so that means we need the layout for the
new file before we've gotten the response from the MDS.
All files created in a directory will initially inherit the same layout,
so copy off the requisite info from the first synchronous create in the
directory, and save it in a new i_cached_layout field. Zero out the
layout when we lose Dc caps in the dir.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Newer versions of the MDS will flag a dentry as "primary". In later
patches, we'll need to consult this info, so track it in di->flags.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
...and ensure that such requests are never queued. The MDS has need to
know that a request is asynchronous so add flags and proper
infrastructure for that.
Also, delegated inode numbers and directory caps are associated with the
session, so ensure that async requests are always transmitted on the
first attempt and are never queued to wait for session reestablishment.
If it does end up looking like we'll need to queue the request, then
have it return -EJUKEBOX so the caller can reattempt with a synchronous
request.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
In future patches we'll be taking and relying on Fx caps. Add proper
refcounting for them.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Currently, we could have an open-by-handle (or NFS server) call
into the filesystem and start working with an inode before it's
properly filled out.
Don't clear I_NEW until we have filled out the inode, and discard it
properly if that fails. Note that we occasionally take an extra
reference to the inode to ensure that we don't put the last reference in
discard_new_inode, but rather leave it for ceph_async_iput.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
If the caller passes in a NULL cap_reservation, and we can't allocate
one then ensure that we fail gracefully.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
We should not play with dcache without parent locked...
Cc: stable@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
If we have Fx caps, and the we're truncating the size to be larger, then
we'll cache the size attribute change, but the mtime won't be updated.
Move the size handling before the mtime, and add ATTR_MTIME to ia_valid
in that case to make sure the mtime also gets updated.
This fixes xfstest generic/313.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Use errseq_t to track and report errors of async metadata operations,
similar to how kernel handles errors during writeback.
If any dirty caps or any unsafe request gets dropped during session
eviction, record -EIO in corresponding inode's i_meta_err. The error
will be reported by subsequent fsync,
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
When filling an inode with info from the MDS, i_blkbits is being
initialized using fl_stripe_unit, which contains the stripe unit in
bytes. Unfortunately, this doesn't make sense for directories as they
have fl_stripe_unit set to '0'. This means that i_blkbits will be set
to 0xff, causing an UBSAN undefined behaviour in i_blocksize():
UBSAN: Undefined behaviour in ./include/linux/fs.h:731:12
shift exponent 255 is too large for 32-bit type 'int'
Fix this by initializing i_blkbits to CEPH_BLOCK_SHIFT if fl_stripe_unit
is zero.
Signed-off-by: Luis Henriques <lhenriques@suse.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Calling ceph_buffer_put() in fill_inode() may result in freeing the
i_xattrs.blob buffer while holding the i_ceph_lock. This can be fixed by
postponing the call until later, when the lock is released.
The following backtrace was triggered by fstests generic/070.
BUG: sleeping function called from invalid context at mm/vmalloc.c:2283
in_atomic(): 1, irqs_disabled(): 0, pid: 3852, name: kworker/0:4
6 locks held by kworker/0:4/3852:
#0: 000000004270f6bb ((wq_completion)ceph-msgr){+.+.}, at: process_one_work+0x1b8/0x5f0
#1: 00000000eb420803 ((work_completion)(&(&con->work)->work)){+.+.}, at: process_one_work+0x1b8/0x5f0
#2: 00000000be1c53a4 (&s->s_mutex){+.+.}, at: dispatch+0x288/0x1476
#3: 00000000559cb958 (&mdsc->snap_rwsem){++++}, at: dispatch+0x2eb/0x1476
#4: 000000000d5ebbae (&req->r_fill_mutex){+.+.}, at: dispatch+0x2fc/0x1476
#5: 00000000a83d0514 (&(&ci->i_ceph_lock)->rlock){+.+.}, at: fill_inode.isra.0+0xf8/0xf70
CPU: 0 PID: 3852 Comm: kworker/0:4 Not tainted 5.2.0+ #441
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58-prebuilt.qemu.org 04/01/2014
Workqueue: ceph-msgr ceph_con_workfn
Call Trace:
dump_stack+0x67/0x90
___might_sleep.cold+0x9f/0xb1
vfree+0x4b/0x60
ceph_buffer_release+0x1b/0x60
fill_inode.isra.0+0xa9b/0xf70
ceph_fill_trace+0x13b/0xc70
? dispatch+0x2eb/0x1476
dispatch+0x320/0x1476
? __mutex_unlock_slowpath+0x4d/0x2a0
ceph_con_workfn+0xc97/0x2ec0
? process_one_work+0x1b8/0x5f0
process_one_work+0x244/0x5f0
worker_thread+0x4d/0x3e0
kthread+0x105/0x140
? process_one_work+0x5f0/0x5f0
? kthread_park+0x90/0x90
ret_from_fork+0x3a/0x50
Signed-off-by: Luis Henriques <lhenriques@suse.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
ceph_drop_inode() implementation is not any different from the generic
function, thus there's no point in keeping it around.
Signed-off-by: Luis Henriques <lhenriques@suse.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
remove_session_caps() relies on __wait_on_freeing_inode(), to wait for
freeing inode to remove its caps. But VFS wakes freeing inode waiters
before calling destroy_inode().
Cc: stable@vger.kernel.org
Link: https://tracker.ceph.com/issues/40102
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
When creating new file/directory, use security_dentry_init_security() to
prepare selinux context for the new inode, then send openc/mkdir request
to MDS, together with selinux xattr.
security_dentry_init_security() only supports single security module and
only selinux has dentry_init_security hook. So only selinux is supported
for now. We can add support for other security modules once kernel has a
generic version of dentry_init_security()
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
d_name_cmp() and update_dentry_lease() lock and unlock dentry->d_lock
respectively. Dentry may get renamed between them. The fix is moving
the dentry name compare into update_dentry_lease().
This patch introduce two version of update_dentry_lease(). One version
is for the case that parent inode is locked. It does not need to check
parent/target inode and dentry name. Another version is for the case
that parent inode is not locked. It checks parent/target inode and
dentry name after locking dentry->d_lock.
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
MDS InodeStat v3 wire structures include a trailing snapshot creation
time member. Unmarshall this and retain it for a future vxattr.
Signed-off-by: David Disseldorp <ddiss@suse.de>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
iput_final() may wait for reahahead pages. The wait can cause deadlock.
For example:
Workqueue: ceph-msgr ceph_con_workfn [libceph]
Call Trace:
schedule+0x36/0x80
io_schedule+0x16/0x40
__lock_page+0x101/0x140
truncate_inode_pages_range+0x556/0x9f0
truncate_inode_pages_final+0x4d/0x60
evict+0x182/0x1a0
iput+0x1d2/0x220
iterate_session_caps+0x82/0x230 [ceph]
dispatch+0x678/0xa80 [ceph]
ceph_con_workfn+0x95b/0x1560 [libceph]
process_one_work+0x14d/0x410
worker_thread+0x4b/0x460
kthread+0x105/0x140
ret_from_fork+0x22/0x40
Workqueue: ceph-msgr ceph_con_workfn [libceph]
Call Trace:
__schedule+0x3d6/0x8b0
schedule+0x36/0x80
schedule_preempt_disabled+0xe/0x10
mutex_lock+0x2f/0x40
ceph_check_caps+0x505/0xa80 [ceph]
ceph_put_wrbuffer_cap_refs+0x1e5/0x2c0 [ceph]
writepages_finish+0x2d3/0x410 [ceph]
__complete_request+0x26/0x60 [libceph]
handle_reply+0x6c8/0xa10 [libceph]
dispatch+0x29a/0xbb0 [libceph]
ceph_con_workfn+0x95b/0x1560 [libceph]
process_one_work+0x14d/0x410
worker_thread+0x4b/0x460
kthread+0x105/0x140
ret_from_fork+0x22/0x40
In above example, truncate_inode_pages_range() waits for readahead pages
while holding s_mutex. ceph_check_caps() waits for s_mutex and blocks
OSD dispatch thread. Later OSD replies (for readahead) can't be handled.
ceph_check_caps() also may lock snap_rwsem for read. So similar deadlock
can happen if iput_final() is called while holding snap_rwsem.
In general, it's not good to call iput_final() inside MDS/OSD dispatch
threads or while holding any mutex.
The fix is introducing ceph_async_iput(), which calls iput_final() in
workqueue.
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
We have three workqueue for inode works. Later patch will introduce
one more work for inode. It's not good to introcuce more workqueue
and add more 'struct work_struct' to 'struct ceph_inode_info'.
Signed-off-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
- a fix to enforce quotas set above the mount point (Luis Henriques)
- support for exporting snapshots through NFS (Zheng Yan)
- proper statx implementation (Jeff Layton). statx flags are mapped
to MDS caps, with AT_STATX_{DONT,FORCE}_SYNC taken into account.
- some follow-up dentry name handling fixes, in particular elimination
of our hand-rolled helper and the switch to __getname() as suggested
by Al (Jeff Layton)
- a set of MDS client cleanups in preparation for async MDS requests
in the future (Jeff Layton)
- a fix to sync the filesystem before remounting (Jeff Layton)
On the rbd side, work is on-going on object-map and fast-diff image
features.
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Merge tag 'ceph-for-5.2-rc1' of git://github.com/ceph/ceph-client
Pull ceph updates from Ilya Dryomov:
"On the filesystem side we have:
- a fix to enforce quotas set above the mount point (Luis Henriques)
- support for exporting snapshots through NFS (Zheng Yan)
- proper statx implementation (Jeff Layton). statx flags are mapped
to MDS caps, with AT_STATX_{DONT,FORCE}_SYNC taken into account.
- some follow-up dentry name handling fixes, in particular
elimination of our hand-rolled helper and the switch to __getname()
as suggested by Al (Jeff Layton)
- a set of MDS client cleanups in preparation for async MDS requests
in the future (Jeff Layton)
- a fix to sync the filesystem before remounting (Jeff Layton)
On the rbd side, work is on-going on object-map and fast-diff image
features"
* tag 'ceph-for-5.2-rc1' of git://github.com/ceph/ceph-client: (29 commits)
ceph: flush dirty inodes before proceeding with remount
ceph: fix unaligned access in ceph_send_cap_releases
libceph: make ceph_pr_addr take an struct ceph_entity_addr pointer
libceph: fix unaligned accesses in ceph_entity_addr handling
rbd: don't assert on writes to snapshots
rbd: client_mutex is never nested
ceph: print inode number in __caps_issued_mask debugging messages
ceph: just call get_session in __ceph_lookup_mds_session
ceph: simplify arguments and return semantics of try_get_cap_refs
ceph: fix comment over ceph_drop_caps_for_unlink
ceph: move wait for mds request into helper function
ceph: have ceph_mdsc_do_request call ceph_mdsc_submit_request
ceph: after an MDS request, do callback and completions
ceph: use pathlen values returned by set_request_path_attr
ceph: use __getname/__putname in ceph_mdsc_build_path
ceph: use ceph_mdsc_build_path instead of clone_dentry_name
ceph: fix potential use-after-free in ceph_mdsc_build_path
ceph: dump granular cap info in "caps" debugfs file
ceph: make iterate_session_caps a public symbol
ceph: fix NULL pointer deref when debugging is enabled
...
Pull vfs inode freeing updates from Al Viro:
"Introduction of separate method for RCU-delayed part of
->destroy_inode() (if any).
Pretty much as posted, except that destroy_inode() stashes
->free_inode into the victim (anon-unioned with ->i_fops) before
scheduling i_callback() and the last two patches (sockfs conversion
and folding struct socket_wq into struct socket) are excluded - that
pair should go through netdev once davem reopens his tree"
* 'work.icache' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (58 commits)
orangefs: make use of ->free_inode()
shmem: make use of ->free_inode()
hugetlb: make use of ->free_inode()
overlayfs: make use of ->free_inode()
jfs: switch to ->free_inode()
fuse: switch to ->free_inode()
ext4: make use of ->free_inode()
ecryptfs: make use of ->free_inode()
ceph: use ->free_inode()
btrfs: use ->free_inode()
afs: switch to use of ->free_inode()
dax: make use of ->free_inode()
ntfs: switch to ->free_inode()
securityfs: switch to ->free_inode()
apparmor: switch to ->free_inode()
rpcpipe: switch to ->free_inode()
bpf: switch to ->free_inode()
mqueue: switch to ->free_inode()
ufs: switch to ->free_inode()
coda: switch to ->free_inode()
...
cephfs can benefit from statx. We can have the client just request caps
sufficient for the needed attributes and leave off the rest.
Also, recognize when AT_STATX_DONT_SYNC is set, and just scrape the
inode without doing any call in that case. Force a call to the MDS in
the event that AT_STATX_FORCE_SYNC is set.
Link: http://tracker.ceph.com/issues/39258
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: "Yan, Zheng" <zyan@redhat.com>
Reviewed-by: David Howells <dhowells@redhat.com>
Reviewed-by: Sage Weil <sage@redhat.com>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
