Commit Graph

395 Commits

Author SHA1 Message Date
Christian Brauner
4609e1f18e
fs: port ->permission() to pass mnt_idmap
Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2023-01-19 09:24:28 +01:00
Christian Brauner
13e83a4923
fs: port ->set_acl() to pass mnt_idmap
Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2023-01-19 09:24:27 +01:00
Christian Brauner
e18275ae55
fs: port ->rename() to pass mnt_idmap
Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2023-01-19 09:24:26 +01:00
Christian Brauner
5ebb29bee8
fs: port ->mknod() to pass mnt_idmap
Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2023-01-19 09:24:26 +01:00
Christian Brauner
c54bd91e9e
fs: port ->mkdir() to pass mnt_idmap
Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2023-01-19 09:24:26 +01:00
Christian Brauner
7a77db9551
fs: port ->symlink() to pass mnt_idmap
Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2023-01-19 09:24:25 +01:00
Christian Brauner
6c960e68aa
fs: port ->create() to pass mnt_idmap
Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2023-01-19 09:24:25 +01:00
Christian Brauner
b74d24f7a7
fs: port ->getattr() to pass mnt_idmap
Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2023-01-19 09:24:25 +01:00
Christian Brauner
c1632a0f11
fs: port ->setattr() to pass mnt_idmap
Convert to struct mnt_idmap.

Last cycle we merged the necessary infrastructure in
256c8aed2b ("fs: introduce dedicated idmap type for mounts").
This is just the conversion to struct mnt_idmap.

Currently we still pass around the plain namespace that was attached to a
mount. This is in general pretty convenient but it makes it easy to
conflate namespaces that are relevant on the filesystem with namespaces
that are relevent on the mount level. Especially for non-vfs developers
without detailed knowledge in this area this can be a potential source for
bugs.

Once the conversion to struct mnt_idmap is done all helpers down to the
really low-level helpers will take a struct mnt_idmap argument instead of
two namespace arguments. This way it becomes impossible to conflate the two
eliminating the possibility of any bugs. All of the vfs and all filesystems
only operate on struct mnt_idmap.

Acked-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2023-01-19 09:24:02 +01:00
Linus Torvalds
6830d50325 gfs2 fixes
- Revert a change to delete_work_func() that has gone wrong in commit
   c412a97cf6 ("gfs2: Use TRY lock in gfs2_inode_lookup for UNLINKED
   inodes").
 
 - Avoid dequeuing GL_ASYNC glock holders twice by first checking if the
   holder is still queued.
 
 - gfs2: Always check the inode size of inline inodes when reading in
   inodes to prevent corrupt filesystem images from causing weid errors.
 
 - Properly handle a race between gfs2_create_inode() and
   gfs2_inode_lookup() that causes insert_inode_locked4() to return
   -EBUSY.
 
 - Fix and clean up the interaction between gfs2_create_inode() and
   gfs2_evict_inode() by completely handling the inode deallocation and
  destruction in gfs2_evict_inode().
 
 - Remove support for glock holder auto-demotion as we have no current
   plans of using this feature again.
 
 - And a few more minor cleanups and clarifications.
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Merge tag 'gfs2-v6.1-rc7-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2

Pull gfs2 updtaes from Andreas Gruenbacher:

 - Revert a change to delete_work_func() that has gone wrong in commit
   c412a97cf6 ("gfs2: Use TRY lock in gfs2_inode_lookup for UNLINKED
   inodes").

 - Avoid dequeuing GL_ASYNC glock holders twice by first checking if the
   holder is still queued.

 - gfs2: Always check the inode size of inline inodes when reading in
   inodes to prevent corrupt filesystem images from causing weid errors.

 - Properly handle a race between gfs2_create_inode() and
   gfs2_inode_lookup() that causes insert_inode_locked4() to return
   -EBUSY.

 - Fix and clean up the interaction between gfs2_create_inode() and
   gfs2_evict_inode() by completely handling the inode deallocation and
   destruction in gfs2_evict_inode().

 - Remove support for glock holder auto-demotion as we have no current
   plans of using this feature again.

 - And a few more minor cleanups and clarifications.

* tag 'gfs2-v6.1-rc7-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
  gfs2: Remove support for glock holder auto-demotion (2)
  gfs2: Remove support for glock holder auto-demotion
  gfs2: Minor gfs2_try_evict cleanup
  gfs2: Partially revert gfs2_inode_lookup change
  gfs2: Add gfs2_inode_lookup comment
  gfs2: Uninline and improve glock_{set,clear}_object
  gfs2: Simply dequeue iopen glock in gfs2_evict_inode
  gfs2: Clean up after gfs2_create_inode rework
  gfs2: Avoid dequeuing GL_ASYNC glock holders twice
  gfs2: Make gfs2_glock_hold return its glock argument
  gfs2: Always check inode size of inline inodes
  gfs2: Cosmetic gfs2_dinode_{in,out} cleanup
  gfs2: Handle -EBUSY result of insert_inode_locked4
  gfs2: Fix and clean up create / evict interaction
  gfs2: Clean up initialization of "ip" in gfs2_create_inode
  gfs2: Get rid of ghs[] in gfs2_create_inode
  gfs2: Add extra error check in alloc_dinode
2022-12-17 08:18:04 -06:00
Andreas Gruenbacher
2ec750a01d gfs2: Add gfs2_inode_lookup comment
Add comment on when and why gfs2_cancel_delete_work() needs to be
skipped in gfs2_inode_lookup().

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2022-12-06 16:06:32 +01:00
Andreas Gruenbacher
4ec3c19d05 gfs2: Handle -EBUSY result of insert_inode_locked4
When creating a new inode, there is a small chance that an inode lookup
for a previous version of the same inode is still in progress.  In that
case, that previous lookup will eventually fail, but we may still need
to retry here.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2022-12-05 22:21:23 +01:00
Andreas Gruenbacher
38552ff676 gfs2: Fix and clean up create / evict interaction
When gfs2_create_inode() fails after creating a new inode, it uses the
GIF_FREE_VFS_INODE and GIF_ALLOC_FAILED inode flags to communicate to
gfs2_evict_inode() which parts of the inode need to be deallocated and
destroyed.  In some error cases, the inode ends up being allocated on
disk and then accidentally left behind.  In others, the inode is
partially constructed and then not properly destroyed.  Clean this up by
completely handling the inode deallocation and destruction in
gfs2_evict_inode().

This means that gfs2_evict_inode() may now be faced with partially
constructed inodes, so add the necessary checks to cope with that.  In
particular, make sure that for incompletely constructed inodes, we're
not accessing the buffers backing the on-disk blocks; the contents may
be undefined.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2022-12-02 15:58:00 +01:00
Andreas Gruenbacher
3d0258bc11 gfs2: Clean up initialization of "ip" in gfs2_create_inode
Initialize variable "ip" earlier so that it can be used interchangeably
with "inode" everywhere.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2022-12-02 15:58:00 +01:00
Andreas Gruenbacher
761fdbbce9 gfs2: Get rid of ghs[] in gfs2_create_inode
In gfs2_create_inode, get rid of the ghs array in favor of two separate
variables.  This makes the code much less irritating.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2022-12-02 15:58:00 +01:00
Andreas Gruenbacher
35c23fba4e gfs2: Add extra error check in alloc_dinode
We have reserved the number of blocks we want to allocate, so the actual
allocation isn't expected to fail.  Nevertheless, make the code behave
correctly even when things go wrong.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2022-12-02 15:58:00 +01:00
Christian Brauner
cac2f8b8d8
fs: rename current get acl method
The current way of setting and getting posix acls through the generic
xattr interface is error prone and type unsafe. The vfs needs to
interpret and fixup posix acls before storing or reporting it to
userspace. Various hacks exist to make this work. The code is hard to
understand and difficult to maintain in it's current form. Instead of
making this work by hacking posix acls through xattr handlers we are
building a dedicated posix acl api around the get and set inode
operations. This removes a lot of hackiness and makes the codepaths
easier to maintain. A lot of background can be found in [1].

The current inode operation for getting posix acls takes an inode
argument but various filesystems (e.g., 9p, cifs, overlayfs) need access
to the dentry. In contrast to the ->set_acl() inode operation we cannot
simply extend ->get_acl() to take a dentry argument. The ->get_acl()
inode operation is called from:

acl_permission_check()
-> check_acl()
   -> get_acl()

which is part of generic_permission() which in turn is part of
inode_permission(). Both generic_permission() and inode_permission() are
called in the ->permission() handler of various filesystems (e.g.,
overlayfs). So simply passing a dentry argument to ->get_acl() would
amount to also having to pass a dentry argument to ->permission(). We
should avoid this unnecessary change.

So instead of extending the existing inode operation rename it from
->get_acl() to ->get_inode_acl() and add a ->get_acl() method later that
passes a dentry argument and which filesystems that need access to the
dentry can implement instead of ->get_inode_acl(). Filesystems like cifs
which allow setting and getting posix acls but not using them for
permission checking during lookup can simply not implement
->get_inode_acl().

This is intended to be a non-functional change.

Link: https://lore.kernel.org/all/20220801145520.1532837-1-brauner@kernel.org [1]
Suggested-by/Inspired-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2022-10-20 10:13:27 +02:00
Christian Brauner
138060ba92
fs: pass dentry to set acl method
The current way of setting and getting posix acls through the generic
xattr interface is error prone and type unsafe. The vfs needs to
interpret and fixup posix acls before storing or reporting it to
userspace. Various hacks exist to make this work. The code is hard to
understand and difficult to maintain in it's current form. Instead of
making this work by hacking posix acls through xattr handlers we are
building a dedicated posix acl api around the get and set inode
operations. This removes a lot of hackiness and makes the codepaths
easier to maintain. A lot of background can be found in [1].

Since some filesystem rely on the dentry being available to them when
setting posix acls (e.g., 9p and cifs) they cannot rely on set acl inode
operation. But since ->set_acl() is required in order to use the generic
posix acl xattr handlers filesystems that do not implement this inode
operation cannot use the handler and need to implement their own
dedicated posix acl handlers.

Update the ->set_acl() inode method to take a dentry argument. This
allows all filesystems to rely on ->set_acl().

As far as I can tell all codepaths can be switched to rely on the dentry
instead of just the inode. Note that the original motivation for passing
the dentry separate from the inode instead of just the dentry in the
xattr handlers was because of security modules that call
security_d_instantiate(). This hook is called during
d_instantiate_new(), d_add(), __d_instantiate_anon(), and
d_splice_alias() to initialize the inode's security context and possibly
to set security.* xattrs. Since this only affects security.* xattrs this
is completely irrelevant for posix acls.

Link: https://lore.kernel.org/all/20220801145520.1532837-1-brauner@kernel.org [1]
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner (Microsoft) <brauner@kernel.org>
2022-10-19 12:55:42 +02:00
Andreas Gruenbacher
c7d7d2d345 gfs2: Merge branch 'for-next.nopid' into for-next
Resolves a conflict in gfs2_inode_lookup() between the following commits:

    gfs2: Use TRY lock in gfs2_inode_lookup for UNLINKED inodes

    gfs2: Mark the remaining process-independent glock holders as GL_NOPID

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2022-10-09 22:56:28 +02:00
Bob Peterson
c412a97cf6 gfs2: Use TRY lock in gfs2_inode_lookup for UNLINKED inodes
Before this patch, delete_work_func() would check for the GLF_DEMOTE
flag on the iopen glock and if set, it would perform special processing.
However, there was a race whereby the GLF_DEMOTE flag could be set by
another process after the check. Then when it called
gfs2_lookup_by_inum() which calls gfs2_inode_lookup(), it tried to lock
the iopen glock in SH mode, but the GLF_DEMOTE flag prevented the
request from being granted. But the iopen glock could never be demoted
because that happens when the inode is evicted, and the evict was never
completed because of the failed lookup.

To fix that, change function gfs2_inode_lookup() so that when
GFS2_BLKST_UNLINKED inodes are searched, it uses the LM_FLAG_TRY flag
for the iopen glock.  If the locking request fails, fail
gfs2_inode_lookup() with -EAGAIN so that delete_work_func() can retry
the operation later.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2022-08-25 15:25:16 +02:00
Andreas Gruenbacher
ebdc416c9c gfs2: Mark the remaining process-independent glock holders as GL_NOPID
Add the GL_NOPID flag for the remaining glock holders which are not
associated with the current process.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2022-06-29 13:07:54 +02:00
Andreas Gruenbacher
29464ee36b gfs2: Switch lock order of inode and iopen glock
This patch tries to fix the continual ABBA deadlocks we keep having
between the iopen and inode glocks. This switches the lock order in
gfs2_inode_lookup and gfs2_create_inode so the iopen glock is always
locked first.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2022-02-15 15:01:40 +01:00
Andreas Gruenbacher
7336905a89 gfs2: gfs2_setattr_size error path fix
When gfs2_setattr_size() fails, it calls gfs2_rs_delete(ip, NULL) to get
rid of any reservations the inode may have.  Instead, it should pass in
the inode's write count as the second parameter to allow
gfs2_rs_delete() to figure out if the inode has any writers left.

In a next step, there are two instances of gfs2_rs_delete(ip, NULL) left
where we know that there can be no other users of the inode.  Replace
those with gfs2_rs_deltree(&ip->i_res) to avoid the unnecessary write
count check.

With that, gfs2_rs_delete() is only called with the inode's actual write
count, so get rid of the second parameter.

Fixes: a097dc7e24 ("GFS2: Make rgrp reservations part of the gfs2_inode structure")
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2022-02-15 15:01:40 +01:00
Andreas Gruenbacher
3d36e57ff7 gfs2: gfs2_create_inode rework
When gfs2_lookup_by_inum() calls gfs2_inode_lookup() for an uncached
inode, gfs2_inode_lookup() will place a new tentative inode into the
inode cache before verifying that there is a valid inode at the given
address.  This can race with gfs2_create_inode() which doesn't check for
duplicates inodes.  gfs2_create_inode() will try to assign the new inode
to the corresponding inode glock, and glock_set_object() will complain
that the glock is still in use by gfs2_inode_lookup's tentative inode.

We noticed this bug after adding commit 486408d690 ("gfs2: Cancel
remote delete work asynchronously") which allowed delete_work_func() to
race with gfs2_create_inode(), but the same race exists for
open-by-handle.

Fix that by switching from insert_inode_hash() to
insert_inode_locked4(), which does check for duplicate inodes.  We know
we've just managed to to allocate the new inode, so an inode tentatively
created by gfs2_inode_lookup() will eventually go away and
insert_inode_locked4() will always succeed.

In addition, don't flush the inode glock work anymore (this can now only
make things worse) and clean up glock_{set,clear}_object for the inode
glock somewhat.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-12-02 12:41:10 +01:00
Andreas Gruenbacher
5f6e13baeb gfs2: gfs2_inode_lookup rework
Rework gfs2_inode_lookup() to only set up the new inode's glocks after
verifying that the new inode is valid.

There is no need for flushing the inode glock work queue anymore now,
so remove that as well.

While at it, get rid of the useless wrapper around iget5_locked() and
its unnecessary is_bad_inode() check.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-12-02 12:41:09 +01:00
Andreas Gruenbacher
b8e12e3599 gfs2: gfs2_inode_lookup cleanup
In gfs2_inode_lookup, once the inode has been looked up, we check if the
inode generation (no_formal_ino) is the one we're looking for.  If it
isn't and the inode wasn't in the inode cache, we discard the newly
looked up inode.  This is unnecessary, complicates the code, and makes
future changes to gfs2_inode_lookup harder, so change the code to retain
newly looked up inodes instead.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-12-02 12:41:09 +01:00
Bob Peterson
8793e14985 gfs2: set glock object after nq
Before this patch, function gfs2_create_inode called glock_set_object to
set the gl_object for inode and iopen glocks before the glock was locked.
That's wrong because other competing processes like evict may be
blocked waiting for the glock and still have gl_object set before the
actual eviction can take place.

This patch moves the call to glock_set_object until after the glock is
acquire in function gfs2_create_inode, so it waits for possibly
competing evicts to finish their processing first.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-10-25 08:42:19 +02:00
Bob Peterson
ec1d398dd7 gfs2: Eliminate GIF_INVALID flag
With the addition of the new GLF_INSTANTIATE_NEEDED flag, the
GIF_INVALID flag is now redundant. This patch removes it.
Since inode_instantiate is only called when instantiation is needed,
the check in inode_instantiate is removed too.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-10-25 08:42:19 +02:00
Bob Peterson
f2e70d8f2f gfs2: fix GL_SKIP node_scope problems
Before this patch, when a glock was locked, the very first holder on the
queue would unlock the lockref and call the go_instantiate glops function
(if one existed), unless GL_SKIP was specified. When we introduced the new
node-scope concept, we allowed multiple holders to lock glocks in EX mode
and share the lock.

But node-scope introduced a new problem: if the first holder has GL_SKIP
and the next one does NOT, since it is not the first holder on the queue,
the go_instantiate op was not called. Eventually the GL_SKIP holder may
call the instantiate sub-function (e.g. gfs2_rgrp_bh_get) but there was
still a window of time in which another non-GL_SKIP holder assumes the
instantiate function had been called by the first holder. In the case of
rgrp glocks, this led to a NULL pointer dereference on the buffer_heads.

This patch tries to fix the problem by introducing two new glock flags:

GLF_INSTANTIATE_NEEDED, which keeps track of when the instantiate function
needs to be called to "fill in" or "read in" the object before it is
referenced.

GLF_INSTANTIATE_IN_PROG which is used to determine when a process is
in the process of reading in the object. Whenever a function needs to
reference the object, it checks the GLF_INSTANTIATE_NEEDED flag, and if
set, it sets GLF_INSTANTIATE_IN_PROG and calls the glops "go_instantiate"
function.

As before, the gl_lockref spin_lock is unlocked during the IO operation,
which may take a relatively long amount of time to complete. While
unlocked, if another process determines go_instantiate is still needed,
it sees GLF_INSTANTIATE_IN_PROG is set, and waits for the go_instantiate
glop operation to be completed. Once GLF_INSTANTIATE_IN_PROG is cleared,
it needs to check GLF_INSTANTIATE_NEEDED again because the other process's
go_instantiate operation may not have been successful.

Functions that previously called the instantiate sub-functions now call
directly into gfs2_instantiate so the new bits are managed properly.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-10-25 08:42:19 +02:00
Bob Peterson
763766c057 gfs2: dequeue iopen holder in gfs2_inode_lookup error
Before this patch, if function gfs2_inode_lookup encountered an error
after it had locked the iopen glock, it never unlocked it, relying on
the evict code to do the cleanup.  The evict code then took the
inode glock while holding the iopen glock, which violates the locking
order.  For example,

 (1) node A does a gfs2_inode_lookup that fails, leaving the iopen glock
     locked.

 (2) node B calls delete_work_func -> gfs2_lookup_by_inum ->
     gfs2_inode_lookup.  It locks the inode glock and blocks trying to
     lock the iopen glock, which is held by node A.

 (3) node A eventually calls gfs2_evict_inode -> evict_should_delete.
     It blocks trying to lock the inode glock, which is now held by
     node B.

This patch introduces error handling to function gfs2_inode_lookup
so it properly dequeues held iopen glocks on errors.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-10-25 08:42:18 +02:00
Andreas Gruenbacher
d75b9fa053 gfs2: Switch to may_setattr in gfs2_setattr
The permission check in gfs2_setattr is an old and outdated version of
may_setattr().  Switch to the updated version.

Fixes fstest generic/079.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2021-08-13 00:41:05 -04:00
Linus Torvalds
f2c80837e2 Changes in gfs2:
- Fix some compiler and kernel-doc warnings.
 
 - Various minor cleanups and optimizations.
 
 - Add a new sysfs gfs2 status file with some filesystem wide
   information.
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Merge tag 'gfs2-for-5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2

Pull gfs2 updates from Andreas Gruenbacher:

 - Fix some compiler and kernel-doc warnings

 - Various minor cleanups and optimizations

 - Add a new sysfs gfs2 status file with some filesystem wide
   information

* tag 'gfs2-for-5.13' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
  gfs2: Fix fall-through warnings for Clang
  gfs2: Fix a number of kernel-doc warnings
  gfs2: Make gfs2_setattr_simple static
  gfs2: Add new sysfs file for gfs2 status
  gfs2: Silence possible null pointer dereference warning
  gfs2: Turn gfs2_meta_indirect_buffer into gfs2_meta_buffer
  gfs2: Replace gfs2_lblk_to_dblk with gfs2_get_extent
  gfs2: Turn gfs2_extent_map into gfs2_{get,alloc}_extent
  gfs2: Add new gfs2_iomap_get helper
  gfs2: Remove unused variable sb_format
  gfs2: Fix dir.c function parameter descriptions
  gfs2: Eliminate gh parameter from go_xmote_bh func
  gfs2: don't create empty buffers for NO_CREATE
2021-04-29 10:33:35 -07:00
Gustavo A. R. Silva
e5966cf20f gfs2: Fix fall-through warnings for Clang
In preparation to enable -Wimplicit-fallthrough for Clang, fix multiple
warnings by explicitly adding multiple goto statements instead of just
letting the code fall through to the next case.

Link: https://github.com/KSPP/linux/issues/115
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-04-20 22:38:21 +02:00
Miklos Szeredi
88b631cbfb gfs2: 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: Andreas Gruenbacher <agruenba@redhat.com>
2021-04-12 15:04:29 +02:00
Lee Jones
c551f66c5d gfs2: Fix a number of kernel-doc warnings
Building the kernel with W=1 results in a number of kernel-doc warnings
like incorrect function names and parameter descriptions.  Fix those,
mostly by adding missing parameter descriptions, removing left-over
descriptions, and demoting some less important kernel-doc comments into
regular comments.

Originally proposed by Lee Jones; improved and combined into a single
patch by Andreas.

Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-04-09 22:14:13 +02:00
Andreas Gruenbacher
a4122a95ce gfs2: Make gfs2_setattr_simple static
This function is only used in inode.c.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-04-08 15:07:21 +02:00
Linus Torvalds
5ceabb6078 Merge branch 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull misc vfs updates from Al Viro:
 "Assorted stuff pile - no common topic here"

* 'work.misc' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  whack-a-mole: don't open-code iminor/imajor
  9p: fix misuse of sscanf() in v9fs_stat2inode()
  audit_alloc_mark(): don't open-code ERR_CAST()
  fs/inode.c: make inode_init_always() initialize i_ino to 0
  vfs: don't unnecessarily clone write access for writable fds
2021-02-27 08:07:12 -08:00
Linus Torvalds
f6e1e1d1e1 Changes in gfs2:
* Log space and revoke accounting rework to fix some failed asserts.
 * Local resource group glock sharing for better local performance.
 * Add support for version 1802 filesystems: trusted xattr support and
   '-o rgrplvb' mounts by default.
 * Actually synchronize on the inode glock's FREEING bit during withdraw
   ("gfs2: fix glock confusion in function signal_our_withdraw").
 * Fix parallel recovery of multiple journals ("gfs2: keep bios separate
   for each journal").
 * Various other bug fixes.
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Merge tag 'gfs2-for-5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2

Pull gfs2 updates from Andreas Gruenbacher:

 - Log space and revoke accounting rework to fix some failed asserts.

 - Local resource group glock sharing for better local performance.

 - Add support for version 1802 filesystems: trusted xattr support and
   '-o rgrplvb' mounts by default.

 - Actually synchronize on the inode glock's FREEING bit during withdraw
   ("gfs2: fix glock confusion in function signal_our_withdraw").

 - Fix parallel recovery of multiple journals ("gfs2: keep bios separate
   for each journal").

 - Various other bug fixes.

* tag 'gfs2-for-5.12' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2: (49 commits)
  gfs2: Don't get stuck with I/O plugged in gfs2_ail1_flush
  gfs2: Per-revoke accounting in transactions
  gfs2: Rework the log space allocation logic
  gfs2: Minor calc_reserved cleanup
  gfs2: Use resource group glock sharing
  gfs2: Allow node-wide exclusive glock sharing
  gfs2: Add local resource group locking
  gfs2: Add per-reservation reserved block accounting
  gfs2: Rename rs_{free -> requested} and rd_{reserved -> requested}
  gfs2: Check for active reservation in gfs2_release
  gfs2: Don't search for unreserved space twice
  gfs2: Only pass reservation down to gfs2_rbm_find
  gfs2: Also reflect single-block allocations in rgd->rd_extfail_pt
  gfs2: Recursive gfs2_quota_hold in gfs2_iomap_end
  gfs2: Add trusted xattr support
  gfs2: Enable rgrplvb for sb_fs_format 1802
  gfs2: Don't skip dlm unlock if glock has an lvb
  gfs2: Lock imbalance on error path in gfs2_recover_one
  gfs2: Move function gfs2_ail_empty_tr
  gfs2: Get rid of current_tail()
  ...
2021-02-23 14:04:04 -08:00
Al Viro
6f24784f00 whack-a-mole: don't open-code iminor/imajor
several instances creeped back into the tree...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2021-02-23 10:25:29 -05:00
Bob Peterson
4fc7ec31c3 gfs2: Use resource group glock sharing
This patch takes advantage of the new glock holder sharing feature for
resource groups.  We have already introduced local resource group
locking in a previous patch, so competing accesses of local processes
are already under control.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-02-17 19:30:28 +01:00
Christian Brauner
549c729771
fs: make helpers idmap mount aware
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>
2021-01-24 14:27:20 +01:00
Christian Brauner
0d56a4518d
stat: handle idmapped mounts
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>
2021-01-24 14:27:17 +01:00
Christian Brauner
e65ce2a50c
acl: handle idmapped mounts
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>
2021-01-24 14:27:17 +01:00
Christian Brauner
2f221d6f7b
attr: handle idmapped mounts
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>
2021-01-24 14:27:16 +01:00
Christian Brauner
47291baa8d
namei: make permission helpers idmapped mount aware
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>
2021-01-24 14:27:16 +01:00
Andreas Gruenbacher
a55a47a3bc Revert "GFS2: Prevent delete work from occurring on glocks used for create"
Since commit a0e3cc65fa ("gfs2: Turn gl_delete into a delayed work"), we're
cancelling any pending delete work of an iopen glock before attaching a new
inode to that glock in gfs2_create_inode.  This means that delete_work_func can
no longer be queued or running when attaching the iopen glock to the new inode,
and we can revert commit a4923865ea ("GFS2: Prevent delete work from
occurring on glocks used for create"), which tried to achieve the same but in a
racy way.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2020-12-01 00:25:21 +01:00
Andreas Gruenbacher
e3a77eebfa gfs2: Make inode operations static
The inode operations are not used outside inode.c.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2020-12-01 00:25:21 +01:00
Andreas Gruenbacher
dd0ecf5441 gfs2: Fix deadlock between gfs2_{create_inode,inode_lookup} and delete_work_func
In gfs2_create_inode and gfs2_inode_lookup, make sure to cancel any pending
delete work before taking the inode glock.  Otherwise, gfs2_cancel_delete_work
may block waiting for delete_work_func to complete, and delete_work_func may
block trying to acquire the inode glock in gfs2_inode_lookup.

Reported-by: Alexander Aring <aahringo@redhat.com>
Fixes: a0e3cc65fa ("gfs2: Turn gl_delete into a delayed work")
Cc: stable@vger.kernel.org # v5.8+
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2020-12-01 00:21:10 +01:00
Andreas Gruenbacher
82e938bd53 gfs2: Upgrade shared glocks for atime updates
Commit 20f829999c ("gfs2: Rework read and page fault locking") lifted
the glock lock taking from the low-level ->readpage and ->readahead
address space operations to the higher-level ->read_iter file and
->fault vm operations.  The glocks are still taken in LM_ST_SHARED mode
only.  On filesystems mounted without the noatime option, ->read_iter
sometimes needs to update the atime as well, though.  Right now, this
leads to a failed locking mode assertion in gfs2_dirty_inode.

Fix that by introducing a new update_time inode operation.  There, if
the glock is held non-exclusively, upgrade it to an exclusive lock.

Reported-by: Alexander Aring <aahringo@redhat.com>
Fixes: 20f829999c ("gfs2: Rework read and page fault locking")
Cc: stable@vger.kernel.org # v5.8+
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2020-11-26 19:58:25 +01:00
Andreas Gruenbacher
6bd1c7bd4e gfs2: Don't call cancel_delayed_work_sync from within delete work function
Right now, we can end up calling cancel_delayed_work_sync from within
delete_work_func via gfs2_lookup_by_inum -> gfs2_inode_lookup ->
gfs2_cancel_delete_work.  When that happens, it will result in a
deadlock.  Instead, gfs2_inode_lookup should skip the call to
gfs2_cancel_delete_work when called from delete_work_func (blktype ==
GFS2_BLKST_UNLINKED).

Reported-by: Alexander Ahring Oder Aring <aahringo@redhat.com>
Fixes: a0e3cc65fa ("gfs2: Turn gl_delete into a delayed work")
Cc: stable@vger.kernel.org # v5.8+
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2020-11-02 21:34:47 +01:00