Add a rcu argument to the ->get_acl() callback to allow
get_cached_acl_rcu() to call the ->get_acl() method in the next patch.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
The immutable and append-only properties on an inode are published on
the inode's i_flags and enforced by the VFS.
Create a helper to fill the corresponding STATX_ATTR_ flags in the kstat
structure from the inode's i_flags.
Only orange was converted to use this helper.
Other filesystems could use it in the future.
Suggested-by: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Orangefs df output is whacky. Walt Ligon suggested this might fix it.
It seems way more in line with reality now...
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Matthew Wilcox suggested that perhaps it could be "possible for
rac->file to be NULL if the caller doesn't have a struct file"...
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
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
...
Use the fileattr API to let the VFS handle locking, permission checking and
conversion.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Cc: Mike Marshall <hubcap@omnibond.com>
-----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
...
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>
... and no, file can't be NULL there - it's not called that way *and*
it would've oopsed a few lines prior on such call anyway.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Fix some xfstests regressions that started after 36e2c7421f,
"don't allow splice read/write without explicit ops". Thanks for
help from Dave Chinner and Matthew Wilcox.
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
The variable ret is guaranteed to be 0 in this if (). So we can remove
this assignement.
Signed-off-by: Jing Xiangfeng <jingxiangfeng@huawei.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Al Viro pointed out that I broke some acl functionality...
* ACLs could not be fully removed
* posix_acl_chmod would be called while the old ACL was still cached
* new mode propagated to orangefs server before ACL.
... when I tried to make sure that modes that got changed as a
result of ACL-sets would be sent back to the orangefs server.
Not wanting to try and change the code without having some cases to
test it with, I began to hunt for setfacl examples that were expressible
in pure mode. Along the way I found examples like the following
which confused me:
user A had a file (/home/A/asdf) with mode 740
user B was in user A's group
user C was not in user A's group
setfacl -m u:C:rwx /home/A/asdf
The above setfacl caused ls -l /home/A/asdf to show a mode of 770,
making it appear that all users in user A's group now had full access
to /home/A/asdf, however, user B still only had read acces. Madness.
Anywho, I finally found that the above (whacky as it is) appears to
be "posixly on purpose" and explained in acl(5):
If the ACL has an ACL_MASK entry, the group permissions correspond
to the permissions of the ACL_MASK entry.
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Conversion: John Hubbard's conversion from get_user_pages() to pin_user_pages()
cleanup: Colin Ian King's removal of an unneeded variable initialization.
-----BEGIN PGP SIGNATURE-----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=3A+d
-----END PGP SIGNATURE-----
Merge tag 'for-linus-5.8-ofs1' of git://git.kernel.org/pub/scm/linux/kernel/git/hubcap/linux
Pull orangefs updates from Mike Marshall:
- John Hubbard's conversion from get_user_pages() to pin_user_pages()
- Colin Ian King's removal of an unneeded variable initialization
* tag 'for-linus-5.8-ofs1' of git://git.kernel.org/pub/scm/linux/kernel/git/hubcap/linux:
orangefs: convert get_user_pages() --> pin_user_pages()
orangefs: remove redundant assignment to variable ret
Since the new pair function is introduced, we can call them to clean the
code in orangefs.
Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Mike Marshall <hubcap@omnibond.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Martin Brandenburg <martin@omnibond.com>
Link: http://lkml.kernel.org/r/20200517214718.468-9-guoqing.jiang@cloud.ionos.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This code was using get_user_pages*(), in a "Case 1" scenario
(Direct IO), using the categorization from [1]. That means that it's
time to convert the get_user_pages*() + put_page() calls to
pin_user_pages*() + unpin_user_pages() calls.
There is some helpful background in [2]: basically, this is a small
part of fixing a long-standing disconnect between pinning pages, and
file systems' use of those pages.
[1] Documentation/core-api/pin_user_pages.rst
[2] "Explicit pinning of user-space pages":
https://lwn.net/Articles/807108/
Cc: Mike Marshall <hubcap@omnibond.com>
Cc: Martin Brandenburg <martin@omnibond.com>
Cc: devel@lists.orangefs.org
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
The variable ret is being initialized with a value that is
never read and it is being updated later with a new value. The
initialization is redundant and can be removed.
Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Christoph Hellwig noticed that we were doing some unnecessary
work in orangefs_flush:
orangefs_flush just writes out data on every close(2) call. There is
no need to change anything about the dirty state, especially as
orangefs doesn't treat I_DIRTY_TIMES special in any way. The code
seems to come from partially open coding vfs_fsync.
He sent in a patch with the above commit message and also a
patch that was a reversion of another Orangefs patch I had
sent upstream a while ago. I had to fix his reversion patch
so that it would compile which caused his "don't mess with
I_DIRTY_TIMES" patch to fail to apply. So here I have just
remade his patch and applied it after the fixed reversion patch.
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Christoph Hellwig sent in a reversion of "orangefs: remember count
when reading." because:
->read_iter calls can race with each other and one or
more ->flush calls. Remove the the scheme to store the read
count in the file private data as is is completely racy and
can cause use after free or double free conditions
Christoph's reversion caused Orangefs not to work or to compile. I
added a patch that fixed that, but intel's kbuild test robot pointed
out that sending Christoph's patch followed by my patch upstream, it
would break bisection because of the failure to compile. So I have
combined the reversion plus my patch... here's the commit message
that was in my patch:
Logically, optimal Orangefs "pages" are 4 megabytes. Reading
large Orangefs files 4096 bytes at a time is like trying to
kick a dead whale down the beach. Before Christoph's "Revert
orangefs: remember count when reading." I tried to give users
a knob whereby they could, for example, use "count" in
read(2) or bs with dd(1) to get whatever they considered an
appropriate amount of bytes at a time from Orangefs and fill
as many page cache pages as they could at once.
Without the racy code that Christoph reverted Orangefs won't
even compile, much less work. So this replaces the logic that
used the private file data that Christoph reverted with
a static number of bytes to read from Orangefs.
I ran tests like the following to determine what a
reasonable static number of bytes might be:
dd if=/pvfsmnt/asdf of=/dev/null count=128 bs=4194304
dd if=/pvfsmnt/asdf of=/dev/null count=256 bs=2097152
dd if=/pvfsmnt/asdf of=/dev/null count=512 bs=1048576
.
.
.
dd if=/pvfsmnt/asdf of=/dev/null count=4194304 bs=128
Reads seem faster using the static number, so my "knob code"
wasn't just racy, it wasn't even a good idea...
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Reported-by: kbuild test robot <lkp@intel.com>
if seq_file .next fuction does not change position index,
read after some lseek can generate unexpected output.
https://bugzilla.kernel.org/show_bug.cgi?id=206283
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Orangefs has no open, and orangefs checks file permissions
on each file access. Posix requires that file permissions
be checked on open and nowhere else. Orangefs-through-the-kernel
needs to seem posix compliant.
The VFS opens files, even if the filesystem provides no
method. We can see if a file was successfully opened for
read and or for write by looking at file->f_mode.
When writes are flowing from the page cache, file is no
longer available. We can trust the VFS to have checked
file->f_mode before writing to the page cache.
The mode of a file might change between when it is opened
and IO commences, or it might be created with an arbitrary mode.
We'll make sure we don't hit EACCES during the IO stage by
using UID 0. Some of the time we have access without changing
to UID 0 - how to check?
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
fix: way back in the stone age (2003) mode was set to the magic
number "755" in what is now fs/orangefs/namei.c(orangefs_symlink).
Łukasz Wrochna reported it and Artur Świgoń sent in a patch to change
it to octal. Maybe it shouldn't be a magic number at all but rather
something like "S_IRWXU | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH"...
cleanup: Colin Ian King found a redundant assignment and sent in a
patch to remove it.
-----BEGIN PGP SIGNATURE-----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=ZJ67
-----END PGP SIGNATURE-----
Merge tag 'for-linus-5.4-ofs1' of git://git.kernel.org/pub/scm/linux/kernel/git/hubcap/linux
Pull orangefs updates from Mike Marshall:
"A fix and a cleanup.
The fix: way back in the stone age (2003) mode was set to the magic
number "755" in what is now fs/orangefs/namei.c(orangefs_symlink).
Łukasz Wrochna reported it and Artur Świgoń sent in a patch to change
it to octal. Maybe it shouldn't be a magic number at all but rather
something like "S_IRWXU | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH"...
cleanup: Colin Ian King found a redundant assignment and sent in a
patch to remove it"
[ And no, octal numbers for permissions are a lot more legible than a
binary 'or' of some line noise macros. So 0755 is preferred over
trying to spell it out using "helpful" macros - Linus ]
* tag 'for-linus-5.4-ofs1' of git://git.kernel.org/pub/scm/linux/kernel/git/hubcap/linux:
orangefs: remove redundant assignment to err
orangefs: Add octal zero prefix
Variable err is initialized to a value that is never read and it
is re-assigned later. The initialization is redundant and can
be removed.
Addresses-Coverity: ("Unused value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
This patch adds a missing zero to mode 755 specification required to
express it in octal numeral system.
Reported-by: Łukasz Wrochna <l.wrochna@samsung.com>
Signed-off-by: Artur Świgoń <a.swigon@partner.samsung.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
This file has its own proper style, except that, after a while,
the coding style gets violated and whitespaces are placed on
different ways.
As Sphinx and ReST are very sentitive to whitespace differences,
I had to opt if each entry after required/mandatory/... fields
should start with zero spaces or with a tab. I opted to start them
all from the zero position, in order to avoid needing to break lines
with more than 80 columns, with would make harder for review.
Most of the other changes at porting.rst were made to use an unified
notation with works nice as a text file while also produce a good html
output after being parsed.
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
There are 3 remaining files without an extension inside the fs docs
dir.
Manually convert them to ReST.
In the case of the nfs/exporting.rst file, as the nfs docs
aren't ported yet, I opted to convert and add a :orphan: there,
with should be removed when it gets added into a nfs-specific
part of the fs documentation.
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Unused Value that colin.king@canonical.com sent me and a
related fix I added.
-----BEGIN PGP SIGNATURE-----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=PJuy
-----END PGP SIGNATURE-----
Merge tag 'for-linus-5.3-ofs1' of git://git.kernel.org/pub/scm/linux/kernel/git/hubcap/linux
Pull orangefs updates from Mike Marshall:
"Two small fixes.
This is just a fix for an unused value that Colin King sent me and a
related fix I added"
* tag 'for-linus-5.3-ofs1' of git://git.kernel.org/pub/scm/linux/kernel/git/hubcap/linux:
orangefs: eliminate needless variable assignments
orangefs: remove redundant assignment to variable buffer_index
- Standardize parameter checking for the SETFLAGS and FSSETXATTR ioctls
(which were the file attribute setters for ext4 and xfs and have now
been hoisted to the vfs)
- Only allow the DAX flag to be set on files and directories.
-----BEGIN PGP SIGNATURE-----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=uH2E
-----END PGP SIGNATURE-----
Merge tag 'vfs-fix-ioctl-checking-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux
Pull common SETFLAGS/FSSETXATTR parameter checking from Darrick Wong:
"Here's a patch series that sets up common parameter checking functions
for the FS_IOC_SETFLAGS and FS_IOC_FSSETXATTR ioctl implementations.
The goal here is to reduce the amount of behaviorial variance between
the filesystems where those ioctls originated (ext2 and XFS,
respectively) and everybody else.
- Standardize parameter checking for the SETFLAGS and FSSETXATTR
ioctls (which were the file attribute setters for ext4 and xfs and
have now been hoisted to the vfs)
- Only allow the DAX flag to be set on files and directories"
* tag 'vfs-fix-ioctl-checking-3' of git://git.kernel.org/pub/scm/fs/xfs/xfs-linux:
vfs: only allow FSSETXATTR to set DAX flag on files and dirs
vfs: teach vfs_ioc_fssetxattr_check to check extent size hints
vfs: teach vfs_ioc_fssetxattr_check to check project id info
vfs: create a generic checking function for FS_IOC_FSSETXATTR
vfs: create a generic checking and prep function for FS_IOC_SETFLAGS
The variable buffer_index is being initialized however this is never
read and later it is being reassigned to a new value. The initialization
is redundant and hence can be removed.
Addresses-Coverity: ("Unused Value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Stephen writes:
After merging the driver-core tree, today's linux-next build (x86_64
allmodconfig) produced this warning:
fs/orangefs/orangefs-debugfs.c: In function 'orangefs_debugfs_init':
fs/orangefs/orangefs-debugfs.c:193:1: warning: label 'out' defined but not used [-Wunused-label]
out:
^~~
fs/orangefs/orangefs-debugfs.c: In function 'orangefs_kernel_debug_init':
fs/orangefs/orangefs-debugfs.c:204:17: warning: unused variable 'ret' [-Wunused-variable]
struct dentry *ret;
^~~
Fix this up and change the return type of the function to void as it can
not fail, which cleans up some more code and variables as well.
Cc: Mike Marshall <hubcap@omnibond.com>
Cc: Martin Brandenburg <martin@omnibond.com>
Cc: devel@lists.orangefs.org
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Fixes: f095adba36 ("orangefs: no need to check return value of debugfs_create functions")
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When calling debugfs functions, there is no need to ever check the
return value. The function can work or not, but the code logic should
never do something different based on this.
Cc: Mike Marshall <hubcap@omnibond.com>
Cc: Martin Brandenburg <martin@omnibond.com>
Cc: devel@lists.orangefs.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20190612152204.GA17511@kroah.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Create a generic function to check incoming FS_IOC_SETFLAGS flag values
and later prepare the inode for updates so that we can standardize the
implementations that follow ext4's flag values.
Note that the efivarfs implementation no longer fails a no-op SETFLAGS
without CAP_LINUX_IMMUTABLE since that's the behavior in ext*.
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: David Sterba <dsterba@suse.com>
Reviewed-by: Bob Peterson <rpeterso@redhat.com>
Add SPDX license identifiers to all Make/Kconfig files which:
- Have no license information of any form
These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:
GPL-2.0-only
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Add SPDX license identifiers to all files which:
- Have no license information of any form
- Have MODULE_LICENCE("GPL*") inside which was used in the initial
scan/conversion to ignore the file
These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:
GPL-2.0-only
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To facilitate additional options to get_user_pages_fast() change the
singular write parameter to be gup_flags.
This patch does not change any functionality. New functionality will
follow in subsequent patches.
Some of the get_user_pages_fast() call sites were unchanged because they
already passed FOLL_WRITE or 0 for the write parameter.
NOTE: It was suggested to change the ordering of the get_user_pages_fast()
arguments to ensure that callers were converted. This breaks the current
GUP call site convention of having the returned pages be the final
parameter. So the suggestion was rejected.
Link: http://lkml.kernel.org/r/20190328084422.29911-4-ira.weiny@intel.com
Link: http://lkml.kernel.org/r/20190317183438.2057-4-ira.weiny@intel.com
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Mike Marshall <hubcap@omnibond.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Hogan <jhogan@kernel.org>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Rich Felker <dalias@libc.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
the pagecache" patch series which greatly improves our small IO
performance and helps us pass more xfstests than before.
fix: orangefs: truncate before updating size
Pagecache series: all the rest
-----BEGIN PGP SIGNATURE-----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=uBS+
-----END PGP SIGNATURE-----
Merge tag 'for-linus-5.2-ofs1' of git://git.kernel.org/pub/scm/linux/kernel/git/hubcap/linux
Pull orangefs updates from Mike Marshall:
"This includes one fix and our "Orangefs through the pagecache" patch
series which greatly improves our small IO performance and helps us
pass more xfstests than before.
Fix:
- orangefs: truncate before updating size
Pagecache series:
- all the rest"
* tag 'for-linus-5.2-ofs1' of git://git.kernel.org/pub/scm/linux/kernel/git/hubcap/linux: (23 commits)
orangefs: truncate before updating size
orangefs: copy Orangefs-sized blocks into the pagecache if possible.
orangefs: pass slot index back to readpage.
orangefs: remember count when reading.
orangefs: add orangefs_revalidate_mapping
orangefs: implement writepages
orangefs: write range tracking
orangefs: avoid fsync service operation on flush
orangefs: skip inode writeout if nothing to write
orangefs: move do_readv_writev to direct_IO
orangefs: do not return successful read when the client-core disappeared
orangefs: implement writepage
orangefs: migrate to generic_file_read_iter
orangefs: service ops done for writeback are not killable
orangefs: remove orangefs_readpages
orangefs: reorganize setattr functions to track attribute changes
orangefs: let setattr write to cached inode
orangefs: set up and use backing_dev_info
orangefs: hold i_lock during inode_getattr
orangefs: update attributes rather than relying on server
...
Otherwise we race with orangefs_writepage/orangefs_writepages
which and does not expect i_size < page_offset.
Fixes xfstests generic/129.
Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
->readpage looks in file->private_data to try and find out how the
userspace program set "count" in read(2) or with "dd bs=" or whatever.
->readpage uses "count" and inode->i_size to calculate how much
data Orangefs should deposit in the Orangefs shared buffer, and
remembers which slot the data is in.
After copying data from the Orangefs shared buffer slot into
"the page", readpage tries to increment through the pagecache index
and fill as many pages as it can from the extra data in the shared
buffer. Hopefully these extra pages will soon be needed by the vfs,
and they'll be in the pagecache already.
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Signed-off-by: Martin Brandenburg <martin@omnibond.com>
When userspace deposits more than a page of data into the shared buffer,
we'll need to know which slot it is in when we get back to readpage
so that we can try to use the extra data to fill some extra pages.
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Orangefs wins when it can do IO on large (up to four meg) blocks at a time,
and looses when it has to do tiny "small io" reads and writes. Accessing
Orangefs through the pagecache with the kernel module helps with small io,
both reading and writing, a great deal. Readpage generally tries to fetch a
page (four k) at a time. We'll let users use "count" (as in read(2) or
pread(2) for example) as a knob to control how much data they get from
Orangefs at a time and we'll try to use the data to fill extra
pagecache pages when we get to ->readpage, hopefully resulting in
fewer calls to readpage and Orangefs userspace.
We need a way to remember how they set count so that we can still have
it available when we get to ->readpage.
- We'll use file->private_data to keep track of "count".
We'll wrap generic_file_open with orangefs_file_open and
initialize private_data to NULL there.
- In ->read_iter we have access to both "count" and file, so
we'll kmalloc some space onto file->private_data and store
"count" there.
- We'll kfree file->private_data each time we visit ->flush and
reinitialize it to NULL.
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Signed-off-by: Martin Brandenburg <martin@omnibond.com>
This is modeled after NFS, except our method is different. We use a
simple timer to determine whether to invalidate the page cache. This
is bound to perform.
This addes a sysfs parameter cache_timeout_msecs which controls the time
between page cache invalidations.
Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Go through pages and look for a consecutive writable region. After
finding a number of consecutive writable pages or when finding that
the next page's dirty range is not contiguous and cannot be written
as one request, send the write to the server.
The number of pages is determined by the client-core's buffer size.
Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
Attach the actual range of bytes written to plus the responsible uid/gid
to each dirty page. This information must be sent to the server when
the page is written out.
Now write_begin, page_mkwrite, and invalidatepage keep up with this
information. There are several conditions where they must write out the
page immediately to store the new range. Two non-contiguous ranges
cannot be stored on a single page.
Signed-off-by: Martin Brandenburg <martin@omnibond.com>
Signed-off-by: Mike Marshall <hubcap@omnibond.com>
