Commit Graph

2459 Commits

Author SHA1 Message Date
Bob Peterson
9f9eb5a516 gfs2: Add new sysfs file for gfs2 status
This patch adds a new file: /sys/fs/gfs2/*/status which will report
the status of the file system. Catting this file dumps the current
status of the file system according to various superblock variables.
For example:

Journal Checked:          1
Journal Live:             1
Journal ID:               0
Spectator:                0
Withdrawn:                0
No barriers:              0
No recovery:              0
Demote:                   0
No Journal ID:            1
Mounted RO:               0
RO Recovery:              0
Skip DLM Unlock:          0
Force AIL Flush:          0
FS Frozen:                0
Withdrawing:              0
Withdraw In Prog:         0
Remote Withdraw:          0
Withdraw Recovery:        0
sd_log_error:             0
sd_log_flush_lock:        0
sd_log_num_revoke:        0
sd_log_in_flight:         0
sd_log_blks_needed:       0
sd_log_blks_free:         32768
sd_log_flush_head:        0
sd_log_flush_tail:        5384
sd_log_blks_reserved:     0
sd_log_revokes_available: 503

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-04-08 15:07:21 +02:00
Andreas Gruenbacher
bea906ee16 gfs2: Silence possible null pointer dereference warning
In gfs2_rbm_find, rs is always NULL when minext is NULL, so
gfs2_reservation_check_and_update will never be called on a NULL minext.
This isn't innediately obvious though, so also check for a NULL minext
for better code readability.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-04-03 21:38:12 +02:00
Andreas Gruenbacher
6d8da302ae gfs2: Turn gfs2_meta_indirect_buffer into gfs2_meta_buffer
Instead of only supporting GFS2_METATYPE_DI and GFS2_METATYPE_IN blocks,
make the block type a parameter of gfs2_meta_indirect_buffer and rename
the function to gfs2_meta_buffer.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-04-03 21:38:12 +02:00
Andreas Gruenbacher
152f58c9af gfs2: Replace gfs2_lblk_to_dblk with gfs2_get_extent
We don't need two very similar functions for mapping logical blocks to physical
blocks.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-04-03 21:38:12 +02:00
Andreas Gruenbacher
9153dac13a gfs2: Turn gfs2_extent_map into gfs2_{get,alloc}_extent
Convert gfs2_extent_map to iomap and split it into gfs2_get_extent and
gfs2_alloc_extent.  Instead of hardcoding the extent size, pass it in
via the extlen parameter.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-04-03 21:38:11 +02:00
Andreas Gruenbacher
54992257fe gfs2: Add new gfs2_iomap_get helper
Rename the current gfs2_iomap_get and gfs2_iomap_alloc functions to __*.
Add a new gfs2_iomap_get helper that doesn't expose struct metapath.
Rename gfs2_iomap_get_alloc to gfs2_iomap_alloc.  Use the new helpers
where they make sense.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-04-03 21:38:11 +02:00
Andreas Gruenbacher
0bf3e3273b gfs2: Remove unused variable sb_format
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-04-03 21:38:11 +02:00
Bob Peterson
3ae3a7d62a gfs2: Fix dir.c function parameter descriptions
This patch simply fixes a bunch of function parameter comments
in dir.c that were reported by the kernel test robot.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-04-03 21:32:09 +02:00
Bob Peterson
f68effb308 gfs2: Eliminate gh parameter from go_xmote_bh func
The only glock that uses go_xmote_bh glops function is the freeze glock
which uses freeze_go_xmote_bh. It does not use its gh parameter, so
this patch eliminates the unneeded parameter.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-04-03 21:32:09 +02:00
Bob Peterson
e7dfab8287 gfs2: don't create empty buffers for NO_CREATE
Before this patch, function gfs2_getbuf would create empty buffers when
it was given the NO_CREATE directive from gfs2_journal_wipe. This is a
waste of time: the buffer_head is only used by gfs2_remove_from_journal
to determine if the buffer is pinned (which it won't be if it's newly
created) and if there's an associated bd element (same story).
This patch removes the useless buffer assignment.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-04-03 21:32:09 +02:00
Linus Torvalds
8e29be3468 Two more gfs2 fixes
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Merge tag 'gfs2-v5.12-rc2-fixes2' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2

Pull gfs2 fixes from Andreas Gruenbacher:
 "Two more gfs2 fixes"

* tag 'gfs2-v5.12-rc2-fixes2' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
  gfs2: report "already frozen/thawed" errors
  gfs2: Flag a withdraw if init_threads() fails
2021-04-03 12:15:01 -07:00
Bob Peterson
ff132c5f93 gfs2: report "already frozen/thawed" errors
Before this patch, gfs2's freeze function failed to report an error
when the target file system was already frozen as it should (and as
generic vfs function freeze_super does. Similarly, gfs2's thaw function
failed to report an error when trying to thaw a file system that is not
frozen, as vfs function thaw_super does. The errors were checked, but
it always returned a 0 return code.

This patch adds the missing error return codes to gfs2 freeze and thaw.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-03-25 18:53:38 +01:00
Andrew Price
62dd0f98a0 gfs2: Flag a withdraw if init_threads() fails
Interrupting mount with ^C quickly enough can cause the kthread_run()
calls in gfs2's init_threads() to fail and the error path leads to a
deadlock on the s_umount rwsem. The abridged chain of events is:

  [mount path]
  get_tree_bdev()
    sget_fc()
      alloc_super()
        down_write_nested(&s->s_umount, SINGLE_DEPTH_NESTING); [acquired]
    gfs2_fill_super()
      gfs2_make_fs_rw()
        init_threads()
          kthread_run()
            ( Interrupted )
      [Error path]
      gfs2_gl_hash_clear()
        flush_workqueue(glock_workqueue)
          wait_for_completion()

  [workqueue context]
  glock_work_func()
    run_queue()
      do_xmote()
        freeze_go_sync()
          freeze_super()
            down_write(&sb->s_umount) [deadlock]

In freeze_go_sync() there is a gfs2_withdrawn() check that we can use to
make sure freeze_super() is not called in the error path, so add a
gfs2_withdraw_delayed() call when init_threads() fails.

Ref: https://bugzilla.kernel.org/show_bug.cgi?id=212231

Reported-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: Andrew Price <anprice@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-03-15 15:32:42 +01:00
Al Viro
4a378d8a0d gfs2: be careful with inode refresh
1) gfs2_dinode_in() should *not* touch ->i_rdev on live inodes; even
"zero and immediately reread the same value from dinode" is broken -
have it overlap with ->release() of char device and you can get all
kinds of bogus behaviour.

2) mismatch on inode type on live inodes should be treated as fs
corruption rather than blindly setting ->i_mode.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2021-03-12 22:15:19 -05:00
Linus Torvalds
ce307084c9 block-5.12-2021-03-12-v2
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Merge tag 'block-5.12-2021-03-12-v2' of git://git.kernel.dk/linux-block

Pull block fixes from Jens Axboe:
 "Mostly just random fixes all over the map.

  The only odd-one-out change is finally getting the rename of
  BIO_MAX_PAGES to BIO_MAX_VECS done. This should've been done with the
  multipage bvec change, but it's been left.

  Do it now to avoid hassles around changes piling up for the next merge
  window.

  Summary:

   - NVMe pull request:
      - one more quirk (Dmitry Monakhov)
      - fix max_zone_append_sectors initialization (Chaitanya Kulkarni)
      - nvme-fc reset/create race fix (James Smart)
      - fix status code on aborts/resets (Hannes Reinecke)
      - fix the CSS check for ZNS namespaces (Chaitanya Kulkarni)
      - fix a use after free in a debug printk in nvme-rdma (Lv Yunlong)

   - Follow-up NVMe error fix for NULL 'id' (Christoph)

   - Fixup for the bd_size_lock being IRQ safe, now that the offending
     driver has been dropped (Damien).

   - rsxx probe failure error return (Jia-Ju)

   - umem probe failure error return (Wei)

   - s390/dasd unbind fixes (Stefan)

   - blk-cgroup stats summing fix (Xunlei)

   - zone reset handling fix (Damien)

   - Rename BIO_MAX_PAGES to BIO_MAX_VECS (Christoph)

   - Suppress uevent trigger for hidden devices (Daniel)

   - Fix handling of discard on busy device (Jan)

   - Fix stale cache issue with zone reset (Shin'ichiro)"

* tag 'block-5.12-2021-03-12-v2' of git://git.kernel.dk/linux-block:
  nvme: fix the nsid value to print in nvme_validate_or_alloc_ns
  block: Discard page cache of zone reset target range
  block: Suppress uevent for hidden device when removed
  block: rename BIO_MAX_PAGES to BIO_MAX_VECS
  nvme-pci: add the DISABLE_WRITE_ZEROES quirk for a Samsung PM1725a
  nvme-rdma: Fix a use after free in nvmet_rdma_write_data_done
  nvme-core: check ctrl css before setting up zns
  nvme-fc: fix racing controller reset and create association
  nvme-fc: return NVME_SC_HOST_ABORTED_CMD when a command has been aborted
  nvme-fc: set NVME_REQ_CANCELLED in nvme_fc_terminate_exchange()
  nvme: add NVME_REQ_CANCELLED flag in nvme_cancel_request()
  nvme: simplify error logic in nvme_validate_ns()
  nvme: set max_zone_append_sectors nvme_revalidate_zones
  block: rsxx: fix error return code of rsxx_pci_probe()
  block: Fix REQ_OP_ZONE_RESET_ALL handling
  umem: fix error return code in mm_pci_probe()
  blk-cgroup: Fix the recursive blkg rwstat
  s390/dasd: fix hanging IO request during DASD driver unbind
  s390/dasd: fix hanging DASD driver unbind
  block: Try to handle busy underlying device on discard
2021-03-12 13:25:49 -08:00
Bob Peterson
0efc4976e3 gfs2: bypass log flush if the journal is not live
Patch fe3e397668 ("gfs2: Rework the log space allocation logic")
changed gfs2_log_flush to reserve a set of journal blocks in case no
transaction is active.  However, gfs2_log_flush also gets called in
cases where we don't have an active journal, for example, for spectator
mounts.  In that case, trying to reserve blocks would sleep forever, but
we want gfs2_log_flush to be a no-op instead.

Fixes: fe3e397668 ("gfs2: Rework the log space allocation logic")
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-03-12 15:52:48 +01:00
Bob Peterson
d5bf630f35 gfs2: bypass signal_our_withdraw if no journal
Before this patch, function signal_our_withdraw referenced the journal
inode immediately. But corrupt file systems may have some invalid
journals, in which case our attempt to read it in will withdraw and the
resulting signal_our_withdraw would dereference the NULL value.

This patch adds a check to signal_our_withdraw so that if the journal
has not yet been initialized, it simply returns and does the old-style
withdraw.

Thanks, Andy Price, for his analysis.

Reported-by: syzbot+50a8a9cf8127f2c6f5df@syzkaller.appspotmail.com
Fixes: 601ef0d52e ("gfs2: Force withdraw to replay journals and wait for it to finish")
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-03-12 14:55:23 +01:00
Christoph Hellwig
a8affc03a9 block: rename BIO_MAX_PAGES to BIO_MAX_VECS
Ever since the addition of multipage bio_vecs BIO_MAX_PAGES has been
horribly confusingly misnamed.  Rename it to BIO_MAX_VECS to stop
confusing users of the bio API.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20210311110137.1132391-2-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2021-03-11 07:47:48 -07:00
Bob Peterson
1a5a2cfd34 gfs2: fix use-after-free in trans_drain
This patch adds code to function trans_drain to remove drained
bd elements from the ail lists, if queued, before freeing the bd.
If we don't remove the bd from the ail, function ail_drain will
try to reference the bd after it has been freed by trans_drain.

Thanks to Andy Price for his analysis of the problem.

Reported-by: Andy Price <anprice@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-03-07 17:04:55 +01:00
Yang Li
eb602521f4 gfs2: make function gfs2_make_fs_ro() to void type
It fixes the following warning detected by coccinelle:
./fs/gfs2/super.c:592:5-10: Unneeded variable: "error". Return "0" on
line 628

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-03-07 17:04:55 +01:00
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
Linus Torvalds
7d6beb71da idmapped-mounts-v5.12
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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.pdf
      https://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
  ...
2021-02-23 13:39:45 -08:00
Bob Peterson
17d7768408 gfs2: Don't get stuck with I/O plugged in gfs2_ail1_flush
In gfs2_ail1_flush, we're using I/O plugging to give the block layer a
better chance of merging I/O requests.  If we're too aggressive here, we
can end up waiting on I/O to complete while still plugged.  Fix that in
a way similar to writeback_sb_inodes, except that we can't use
blk_flush_plug because blk_flush_plug_list is not exported.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-02-23 19:01:42 +01:00
Andreas Gruenbacher
803074ad77 Merge branches 'rgrp-glock-sharing' and 'gfs2-revoke' from https://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2.git
Merge the resource group glock sharing feature and the revoke accounting rework.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-02-23 18:54:22 +01:00
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
Linus Torvalds
d61c6a58ae \n
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Merge tag 'lazytime_for_v5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs

Pull lazytime updates from Jan Kara:
 "Cleanups of the lazytime handling in the writeback code making rules
  for calling ->dirty_inode() filesystem handlers saner"

* tag 'lazytime_for_v5.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs:
  ext4: simplify i_state checks in __ext4_update_other_inode_time()
  gfs2: don't worry about I_DIRTY_TIME in gfs2_fsync()
  fs: improve comments for writeback_single_inode()
  fs: drop redundant check from __writeback_single_inode()
  fs: clean up __mark_inode_dirty() a bit
  fs: pass only I_DIRTY_INODE flags to ->dirty_inode
  fs: don't call ->dirty_inode for lazytime timestamp updates
  fat: only specify I_DIRTY_TIME when needed in fat_update_time()
  fs: only specify I_DIRTY_TIME when needed in generic_update_time()
  fs: correctly document the inode dirty flags
2021-02-22 13:17:39 -08:00
Andreas Gruenbacher
2129b42888 gfs2: Per-revoke accounting in transactions
In the log, revokes are stored as a revoke descriptor (struct
gfs2_log_descriptor), followed by zero or more additional revoke blocks
(struct gfs2_meta_header).  On filesystems with a blocksize of 4k, the
revoke descriptor contains up to 503 revokes, and the metadata blocks
contain up to 509 revokes each.  We've so far been reserving space for
revokes in transactions in block granularity, so a lot more space than
necessary was being allocated and then released again.

This patch switches to assigning revokes to transactions individually
instead.  Initially, space for the revoke descriptor is reserved and
handed out to transactions.  When more revokes than that are reserved,
additional revoke blocks are added.  When the log is flushed, the space
for the additional revoke blocks is released, but we keep the space for
the revoke descriptor block allocated.

Transactions may still reserve more revokes than they will actually need
in the end, but now we won't overshoot the target as much, and by only
returning the space for excess revokes at log flush time, we further
reduce the amount of contention between processes.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-02-22 21:16:23 +01:00
Andreas Gruenbacher
fe3e397668 gfs2: Rework the log space allocation logic
The current log space allocation logic is hard to understand or extend.
The principle it that when the log is flushed, we may or may not have a
transaction active that has space allocated in the log.  To deal with
that, we set aside a magical number of blocks to be used in case we
don't have an active transaction.  It isn't clear that the pool will
always be big enough.  In addition, we can't return unused log space at
the end of a transaction, so the number of blocks allocated must exactly
match the number of blocks used.

Simplify this as follows:
 * When transactions are allocated or merged, always reserve enough
   blocks to flush the transaction (err on the safe side).
 * In gfs2_log_flush, return any allocated blocks that haven't been used.
 * Maintain a pool of spare blocks big enough to do one log flush, as
   before.
 * In gfs2_log_flush, when we have no active transaction, allocate a
   suitable number of blocks.  For that, use the spare pool when
   called from logd, and leave the pool alone otherwise.  This means
   that when the log is almost full, logd will still be able to do one
   more log flush, which will result in more log space becoming
   available.

This will make the log space allocator code easier to work with in
the future.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-02-22 21:16:22 +01:00
Andreas Gruenbacher
71b219f4e5 gfs2: Minor calc_reserved cleanup
No functional change.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-02-22 21:16:22 +01:00
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
Bob Peterson
06e908cd9e gfs2: Allow node-wide exclusive glock sharing
Introduce a new LM_FLAG_NODE_SCOPE glock holder flag: when taking a
glock in LM_ST_EXCLUSIVE (EX) mode and with the LM_FLAG_NODE_SCOPE flag
set, the exclusive lock is shared among all local processes who are
holding the glock in EX mode and have the LM_FLAG_NODE_SCOPE flag set.
From the point of view of other nodes, the lock is still held
exclusively.

A future patch will start using this flag to improve performance with
rgrp sharing.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-02-17 19:30:28 +01:00
Andreas Gruenbacher
9e514605c7 gfs2: Add local resource group locking
Prepare for treating resource group glocks as exclusive among nodes but
shared among all tasks running on a node: introduce another layer of
node-specific locking that the local tasks can use to coordinate their
accesses.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-02-17 19:30:28 +01:00
Andreas Gruenbacher
725d0e9d46 gfs2: Add per-reservation reserved block accounting
Add a rs_reserved field to struct gfs2_blkreserv to keep track of the number of
blocks reserved by this particular reservation, and a rd_reserved field to
struct gfs2_rgrpd to keep track of the total number of reserved blocks in the
resource group.  Those blocks are exclusively reserved, as opposed to the
rs_requested / rd_requested blocks which are tracked in the reservation tree
(rd_rstree) and which can be stolen if necessary.

When making a reservation with gfs2_inplace_reserve, rs_reserved is set to
somewhere between ap->min_target and ap->target depending on the number of free
blocks in the resource group.  When allocating blocks with gfs2_alloc_blocks,
rs_reserved is decremented accordingly.  Eventually, any reserved but not
consumed blocks are returned to the resource group by gfs2_inplace_release.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-02-17 19:30:26 +01:00
Andreas Gruenbacher
07974d2a2a gfs2: Rename rs_{free -> requested} and rd_{reserved -> requested}
We keep track of what we've so far been referring to as reservations in
rd_rstree: the nodes in that tree indicate where in a resource group we'd
like to allocate the next couple of blocks for a particular inode.  Local
processes take those as hints, but they may still "steal" blocks from those
extents, so when actually allocating a block, we must double check in the
bitmap whether that block is actually still free.  Likewise, other cluster
nodes may "steal" such blocks as well.

One of the following patches introduces resource group glock sharing, i.e.,
sharing of an exclusively locked resource group glock among local processes to
speed up allocations.  To make that work, we'll need to keep track of how many
blocks we've actually reserved for each inode, so we end up with two different
kinds of reservations.

Distinguish these two kinds by referring to blocks which are reserved but may
still be "stolen" as "requested".  This rename also makes it more obvious that
rs_requested and rd_requested are strongly related.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-02-17 19:26:06 +01:00
Andreas Gruenbacher
0ec9b9ea4f gfs2: Check for active reservation in gfs2_release
In gfs2_release, check if the inode has an active reservation to avoid
unnecessary lock taking.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-02-17 19:26:05 +01:00
Andreas Gruenbacher
b2598965dc gfs2: Don't search for unreserved space twice
If gfs2_inplace_reserve has chosen a resource group but it couldn't make a
reservation there, there are too many other reservations in that resource
group.  In that case, don't even try to respect existing reservations in
gfs2_alloc_blocks.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-02-17 19:26:05 +01:00
Andreas Gruenbacher
3d39fcd16d gfs2: Only pass reservation down to gfs2_rbm_find
Only pass the current reservation down to gfs2_rbm_find rather than the entire
inode; we don't need any of the other information.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-02-17 19:26:05 +01:00
Andreas Gruenbacher
f38e998fbb gfs2: Also reflect single-block allocations in rgd->rd_extfail_pt
Pass a non-NULL minext to gfs2_rbm_find even for single-block allocations.  In
gfs2_rbm_find, also set rgd->rd_extfail_pt when a single-block allocation
fails in a resource group: there is no reason for treating that case
differently.  In gfs2_reservation_check_and_update, only check how many free
blocks we have if more than one block is requested; we already know there's at
least one free block.

In addition, when allocating N blocks fails in gfs2_rbm_find, we need to set
rd_extfail_pt to N - 1 rather than N:  rd_extfail_pt defines the biggest
allocation that might still succeed.

Finally, reset rd_extfail_pt when updating the resource group statistics in
update_rgrp_lvb, as we already do in gfs2_rgrp_bh_get.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-02-17 19:26:05 +01:00
Andreas Gruenbacher
7009fa9cd9 gfs2: Recursive gfs2_quota_hold in gfs2_iomap_end
When starting an iomap write, gfs2_quota_lock_check -> gfs2_quota_lock
-> gfs2_quota_hold is called from gfs2_iomap_begin.  At the end of the
write, before unlocking the quotas, punch_hole -> gfs2_quota_hold can be
called again in gfs2_iomap_end, which is incorrect and leads to a failed
assertion.  Instead, move the call to gfs2_quota_unlock before the call
to punch_hole to fix that.

Fixes: 64bc06bb32 ("gfs2: iomap buffered write support")
Cc: stable@vger.kernel.org # v4.19+
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-02-10 09:51:06 +01:00
Andreas Gruenbacher
866eef48d8 gfs2: Add trusted xattr support
Add support for an additional filesystem version (sb_fs_format = 1802).
When a filesystem with the new version is mounted, the filesystem
supports "trusted.*" xattrs.

In addition, version 1802 filesystems implement a form of forward
compatibility for xattrs: when xattrs with an unknown prefix (ea_type)
are found on a version 1802 filesystem, those attributes are not shown
by listxattr, and they are not accessible by getxattr, setxattr, or
removexattr.

This mechanism might turn out to be what we need in the future, but if
not, we can always bump the filesystem version and break compatibility
instead.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Andrew Price <anprice@redhat.com>
2021-02-08 13:01:24 +01:00
Andrew Price
47b7ec1daa gfs2: Enable rgrplvb for sb_fs_format 1802
Turn on rgrplvb by default for sb_fs_format > 1801.

Mount options still have to override this so a new args field to
differentiate between 'off' and 'not specified' is added, and the new
default is applied only when it's not specified.

Signed-off-by: Andrew Price <anprice@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-02-08 13:00:36 +01:00
Bob Peterson
78178ca844 gfs2: Don't skip dlm unlock if glock has an lvb
Patch fb6791d100 was designed to allow gfs2 to unmount quicker by
skipping the step where it tells dlm to unlock glocks in EX with lvbs.
This was done because when gfs2 unmounts a file system, it destroys the
dlm lockspace shortly after it destroys the glocks so it doesn't need to
unlock them all: the unlock is implied when the lockspace is destroyed
by dlm.

However, that patch introduced a use-after-free in dlm: as part of its
normal dlm_recoverd process, it can call ls_recovery to recover dead
locks. In so doing, it can call recover_rsbs which calls recover_lvb for
any mastered rsbs. Func recover_lvb runs through the list of lkbs queued
to the given rsb (if the glock is cached but unlocked, it will still be
queued to the lkb, but in NL--Unlocked--mode) and if it has an lvb,
copies it to the rsb, thus trying to preserve the lkb. However, when
gfs2 skips the dlm unlock step, it frees the glock and its lvb, which
means dlm's function recover_lvb references the now freed lvb pointer,
copying the freed lvb memory to the rsb.

This patch changes the check in gdlm_put_lock so that it calls
dlm_unlock for all glocks that contain an lvb pointer.

Fixes: fb6791d100 ("GFS2: skip dlm_unlock calls in unmount")
Cc: stable@vger.kernel.org # v3.8+
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-02-05 20:08:47 +01:00
Andreas Gruenbacher
834ec3e1ee gfs2: Lock imbalance on error path in gfs2_recover_one
In gfs2_recover_one, fix a sd_log_flush_lock imbalance when a recovery
pass fails.

Fixes: c9ebc4b737 ("gfs2: allow journal replay to hold sd_log_flush_lock")
Cc: stable@vger.kernel.org # v5.7+
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-02-05 18:18:57 +01:00
Andreas Gruenbacher
76fce65489 gfs2: Move function gfs2_ail_empty_tr
Move this function further up in log.c so that we can use it in the next patch.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-02-03 18:37:25 +01:00
Andreas Gruenbacher
5cb738b5fb gfs2: Get rid of current_tail()
Keep the current value of the updated log tail in the super block as
sb_log_flush_tail instead of computing it on the fly.  This avoids
unnecessary sd_ail_lock taking and cleans up the code.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-02-03 18:37:25 +01:00
Andreas Gruenbacher
297de3180d gfs2: Use a tighter bound in gfs2_trans_begin
Use a tighter bound for the number of blocks required by transactions in
gfs2_trans_begin: in the worst case, we'll have mixed data and metadata,
so we'll need a log desciptor for each type.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-02-03 18:37:25 +01:00
Andreas Gruenbacher
5ae8fff8d0 gfs2: Clean up gfs2_log_reserve
Wake up log waiters in gfs2_log_release when log space has actually become
available.  This is a much better place for the wakeup than gfs2_logd.

Check if enough log space is immeditely available before anything else.  If
there isn't, use io_wait_event to wait instead of open-coding it.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-02-03 18:37:24 +01:00
Andreas Gruenbacher
4a3d049db4 gfs2: Don't wait for journal flush in clean_journal
Commit 588bff95c9 added gfs2_write_log_header() and started using it in
clean_journal(), with an additional call to log_flush_wait() at the end of
gfs2_write_log_header() which is unnecessary for clean_journal().  Move
that call out of gfs2_write_log_header() to restore the previous behavior.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-02-03 18:37:24 +01:00
Andreas Gruenbacher
c1eba1b0bc gfs2: Move lock flush locking to gfs2_trans_{begin,end}
Move the read locking of sd_log_flush_lock from gfs2_log_reserve to
gfs2_trans_begin, and its unlocking from gfs2_log_release to
gfs2_trans_end.  Use gfs2_log_release in two places in which it was open
coded before.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-02-03 18:37:24 +01:00
Andreas Gruenbacher
f3708fb59f gfs2: Get rid of sd_reserving_log
This counter and the associated wait queue are only used so that
gfs2_make_fs_ro can efficiently wait for all pending log space
allocations to fail after setting the filesystem to read-only.  This
comes at the cost of waking up that wait queue very frequently.

Instead, when gfs2_log_reserve fails because the filesystem has become
read-only, Wake up sd_log_waitq.  In gfs2_make_fs_ro, set the file
system read-only and then wait until all the log space has been
released.  Give up and report the problem after a while.  With that,
sd_reserving_log and sd_reserving_log_wait can be removed.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-02-03 18:37:24 +01:00
Andreas Gruenbacher
c968f5788b gfs2: Clean up on-stack transactions
Replace the TR_ALLOCED flag by its inverse, TR_ONSTACK: that way, the flag only
needs to be set in the exceptional case of on-stack transactions.  Split off
__gfs2_trans_begin from gfs2_trans_begin and use it to replace the open-coded
version in gfs2_ail_empty_gl.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-02-03 18:37:10 +01:00
Andreas Gruenbacher
15e20a301a gfs2: Use sb_start_intwrite in gfs2_ail_empty_gl
Commit 2e60d7683c ("GFS2: update freeze code to use freeze/thaw_super
on all nodes") optimized away the sb_start_intwrite ... sb_end_intwrite
protection for the on-stack transactions in gfs2_ail_empty_gl with no
explanation.  I can't think of a valid reason for doing that, so revert
that change.  This simplifies the next commit.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-02-03 16:33:16 +01:00
Bob Peterson
8221894305 gfs2: keep bios separate for each journal
The recovery func can recover multiple journals, but they were all using
the same bio. This resulted in use-after-free related to sdp->sd_log_bio.
This patch moves the variable to the journal descriptor, jd, so that
every recovery can operate on its own bio. And hopefully we never run out.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2021-01-25 08:08:44 -05:00
Bob Peterson
f5f02fde9f gfs2: fix glock confusion in function signal_our_withdraw
If go_free is defined, function signal_our_withdraw is supposed to
synchronize on the GLF_FREEING flag of the inode glock, but it
accidentally does that on the live glock. Fix that and disambiguate
the glock variables.

Fixes: 601ef0d52e ("gfs2: Force withdraw to replay journals and wait for it to finish")
Cc: stable@vger.kernel.org # v5.7+
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2021-01-25 08:08:44 -05:00
Bob Peterson
4a011849f7 Revert "GFS2: Re-add a call to log_flush_wait when flushing the journal"
This reverts commit 428fd95d85.
Patch 428fd95d85b2 added a call to log_flush_wait to function
gfs2_log_flush. Then gfs2_log_flush calls log_write_header which submits
a write request with the REQ_PREFLUSH flag which also forces it to wait.
This patch removes the unnecessary call to log_flush_wait.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2021-01-25 08:08:44 -05:00
Andrew Price
bff2e532d4 gfs2: Fix invalid block size message
Signed-off-by: Andrew Price <anprice@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
2021-01-25 08:08:29 -05:00
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
21cb47be6f
inode: make init and permission helpers idmapped mount aware
The inode_owner_or_capable() helper determines whether the caller is the
owner of the inode or is capable with respect to that inode. Allow it to
handle idmapped mounts. If the inode is accessed through an idmapped
mount it according to 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.

Similarly, allow the inode_init_owner() helper to handle idmapped
mounts. It initializes a new inode on idmapped mounts by mapping the
fsuid and fsgid of the caller from the mount's user namespace. 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/20210121131959.646623-7-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 14:27:16 +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
Christoph Hellwig
2f63296578 iomap: pass a flags argument to iomap_dio_rw
Pass a set of flags to iomap_dio_rw instead of the boolean
wait_for_completion argument.  The IOMAP_DIO_FORCE_WAIT flag
replaces the wait_for_completion, but only needs to be passed
when the iocb isn't synchronous to start with to simplify the
callers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
[djwong: rework xfs_file.c so that we can push iomap changes separately]
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
2021-01-23 10:06:09 -08:00
Zhaoyang Huang
00e8e9bc3c gfs2: amend SLAB_RECLAIM_ACCOUNT on gfs2 related slab cache
As gfs2_quotad_cachep and gfs2_glock_cachep have registered
shrinkers, amending SLAB_RECLAIM_ACCOUNT when creating them,
which improves slab accounting.

Signed-off-by: Zhaoyang Huang <zhaoyang.huang@unisoc.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-01-22 12:19:17 -05:00
Andreas Gruenbacher
6e80674af0 gfs2: Clean up ail2_empty
Clean up the logic in ail2_empty (no functional change).

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-01-19 21:17:50 +01:00
Andreas Gruenbacher
e7501bf88c gfs2: Rename gfs2_{write => flush}_revokes
Function gfs2_write_revokes doesn't actually write any revokes; instead, it
adds revokes to the system transaction during a flush.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-01-19 21:17:49 +01:00
Andreas Gruenbacher
625a8edd5e gfs2: Minor debugging improvement
Split the assert in gfs2_trans_end into two parts.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-01-19 21:17:45 +01:00
Andreas Gruenbacher
6188e8777d gfs2: Some documentation updates
The calc_reserved description claims that buf_limit is 502 (on 4k
filesystems), but it is actually 503.  Fix / clarify the entire
description.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-01-19 21:17:07 +01:00
Andreas Gruenbacher
5a4e9c607e gfs2: Minor gfs2_write_revokes cleanups
Clean up the computations in gfs2_write_revokes (no change in functionality).

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-01-19 21:17:07 +01:00
Andreas Gruenbacher
458094c2c6 gfs2: Simplify the buf_limit and databuf_limit definitions
The BUF_OFFSET and DATABUF_OFFSET definitions are only used in buf_limit
and databuf_limit, respectively, and the rounding done in those
definitions is immediately wiped out by dividing by the element size.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-01-19 21:17:07 +01:00
Andreas Gruenbacher
736b2f778f gfs2: Un-obfuscate function jdesc_find_i
Clean up this function to show that it is trivial.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-01-19 21:16:43 +01:00
Andreas Gruenbacher
560b8eba6b gfs2: Set GBF_FULL flags when reading resource group
When reading a resource group from disk or when receiving the resource group
statistics from a Lock Value Block (LVB), set/clear the GBF_FULL flags of all
bitmaps in that resource group according to whether or not the resource group
is full.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-01-18 16:56:37 +01:00
Andreas Gruenbacher
a12c6fa1de gfs2: Don't clear GBF_FULL flags in rs_deltree
Removing a reservation doesn't make any actual space available, so don't clear
the GBF_FULL flags in that case.  Otherwise, we'll only spend more time
scanning the bitmaps unnecessarily.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-01-18 16:56:37 +01:00
Andreas Gruenbacher
2fdc2fa21b Revert "gfs2: Don't reject a supposedly full bitmap if we have blocks reserved"
This reverts commit e79e0e1428.

It turns out that we're only setting the GBF_FULL flag of a bitmap if we've
been scanning from the beginning of the bitmap until the end and we haven't
found a single free block, and we're not skipping reservations in that process,
either.  This means that in gfs2_rbm_find, we can always skip bitmaps with the
GBF_FULL flag set.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-01-18 16:56:37 +01:00
Andreas Gruenbacher
4272006d95 gfs2: Minor gfs2_inplace_reserve cleanup
Clean up the reservation size computation logic in gfs2_inplace_reserve a
little.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-01-18 16:56:36 +01:00
Andreas Gruenbacher
3ed08befeb gfs2: Get rid of unnecessary variable in gfs2_alloc_blocks
Variable ndata is only used inside "if (!dinode)", so it can be replaced
entirely with *nblocks.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-01-18 16:56:36 +01:00
Andreas Gruenbacher
c65b76b893 gfs2: Only use struct gfs2_rbm for bitmap manipulations
GFS2 uses struct gfs2_rbm to represent a filesystem block number as a
bit position within a resource group.  This representation is used in
the bitmap manipulation code to prevent excessive conversions between
block numbers and bit positions, but also in struct gfs2_blkreserv which
is part of struct gfs2_inode, to mark the start of a reservation.  In
the inode, the bit position representation makes less sense: first, the
start position is used as a block number about as often as a bit
position; second, the bit position representation makes the code
unnecessarily complicated and difficult to read.

Therefore, change struct gfs2_blkreserv to represent the start of a
reservation as a block number instead of a bit position.  (This requires
keeping track of the resource group in gfs2_blkreserv separately.) With
that change, various things can be slightly simplified, and struct
gfs2_rbm can be moved to rgrp.c.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-01-18 16:56:36 +01:00
Andreas Gruenbacher
0eacdd16ad gfs2: Turn gfs2_rbm_incr into gfs2_rbm_add
Change gfs2_rbm_incr to advance an rbm by a given number of blocks.  Use that
in gfs2_reservation_check_and_update to save a gfs2_rbm_to_block ->
gfs2_rbm_from_block round trip.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-01-18 16:56:36 +01:00
Eric Biggers
3aac630b5c gfs2: don't worry about I_DIRTY_TIME in gfs2_fsync()
The I_DIRTY_TIME flag is primary used within the VFS, and there's no
reason for ->fsync() implementations to do anything with it.  This is
because when !datasync, the VFS will expire dirty timestamps before
calling ->fsync().  (See vfs_fsync_range().)  This turns I_DIRTY_TIME
into I_DIRTY_SYNC.

Therefore, change gfs2_fsync() to not check for I_DIRTY_TIME.

Link: https://lore.kernel.org/r/20210112190253.64307-11-ebiggers@kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2021-01-13 17:26:53 +01:00
Eric Biggers
e2728c5621 fs: don't call ->dirty_inode for lazytime timestamp updates
There is no need to call ->dirty_inode for lazytime timestamp updates
(i.e. for __mark_inode_dirty(I_DIRTY_TIME)), since by the definition of
lazytime, filesystems must ignore these updates.  Filesystems only need
to care about the updated timestamps when they expire.

Therefore, only call ->dirty_inode when I_DIRTY_INODE is set.

Based on a patch from Christoph Hellwig:
https://lore.kernel.org/r/20200325122825.1086872-4-hch@lst.de

Link: https://lore.kernel.org/r/20210112190253.64307-6-ebiggers@kernel.org
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Jan Kara <jack@suse.cz>
2021-01-13 17:26:33 +01:00
Bob Peterson
2a6fe26ccf gfs2: make gfs2_log_write_page static
Function gfs2_log_write_page is only used in lops.c, so make it static.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2020-12-31 15:53:35 +01:00
Bob Peterson
96b1454f2e gfs2: move freeze glock outside the make_fs_rw and _ro functions
Before this patch, sister functions gfs2_make_fs_rw and gfs2_make_fs_ro locked
(held) the freeze glock by calling gfs2_freeze_lock and gfs2_freeze_unlock.
The problem is, not all the callers of gfs2_make_fs_ro should be doing this.
The three callers of gfs2_make_fs_ro are: remount (gfs2_reconfigure),
signal_our_withdraw, and unmount (gfs2_put_super). But when unmounting the
file system we can get into the following circular lock dependency:

deactivate_super
   down_write(&s->s_umount); <-------------------------------------- s_umount
   deactivate_locked_super
      gfs2_kill_sb
         kill_block_super
            generic_shutdown_super
               gfs2_put_super
                  gfs2_make_fs_ro
                     gfs2_glock_nq_init sd_freeze_gl
                        freeze_go_sync
                           if (freeze glock in SH)
                              freeze_super (vfs)
                                 down_write(&sb->s_umount); <------- s_umount

This patch moves the hold of the freeze glock outside the two sister rw/ro
functions to their callers, but it doesn't request the glock from
gfs2_put_super, thus eliminating the circular dependency.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2020-12-23 00:54:21 +01:00
Bob Peterson
c77b52c0a1 gfs2: Add common helper for holding and releasing the freeze glock
Many places in the gfs2 code queued and dequeued the freeze glock.
Almost all of them acquire it in SHARED mode, and need to specify the
same LM_FLAG_NOEXP and GL_EXACT flags.

This patch adds common helper functions gfs2_freeze_lock and gfs2_freeze_unlock
to make the code more readable, and to prepare for the next patch.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2020-12-23 00:54:13 +01:00
Bob Peterson
6e5c4ea37a gfs2: in signal_our_withdraw wait for unfreeze of _this_ fs only
Function signal_our_withdraw needs to work on file systems that have been
partially frozen. To do this, it called flush_workqueue(gfs2_freeze_wq).
This this wrong because it waits for *ALL* file systems to be unfrozen, not
just the one we're withdrawing from. It should only wait for the targetted
file system to be unfrozen. Otherwise it would wait until ALL file systems
are thawed before signaling the withdraw.

This patch changes signal_our_withdraw so it calls flush_work() for the target
file system's freeze work (only) to be completed.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2020-12-03 17:04:41 +01:00
Bob Peterson
dd64fe8167 gfs2: Remove sb_start_write from gfs2_statfs_sync
Before this patch, function gfs2_statfs_sync called sb_start_write and
sb_end_write. This is completely unnecessary because, aside from grabbing
glocks, gfs2_statfs_sync does all its updates to statfs with a transaction:
gfs2_trans_begin and _end. And transactions always do sb_start_intwrite in
gfs2_trans_begin and sb_end_intwrite in gfs2_trans_end.

This patch simply removes the call to sb_start_write.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2020-12-03 17:04:24 +01:00
Tom Rix
28c332b941 gfs2: remove trailing semicolons from macro definitions
The macro use will already have a semicolon.

Signed-off-by: Tom Rix <trix@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2020-12-01 00:25:21 +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
Bob Peterson
f39e7d3aae gfs2: Don't freeze the file system during unmount
GFS2's freeze/thaw mechanism uses a special freeze glock to control its
operation. It does this with a sync glock operation (glops.c) called
freeze_go_sync. When the freeze glock is demoted (glock's do_xmote) the
glops function causes the file system to be frozen. This is intended. However,
GFS2's mount and unmount processes also hold the freeze glock to prevent other
processes, perhaps on different cluster nodes, from mounting the frozen file
system in read-write mode.

Before this patch, there was no check in freeze_go_sync for whether a freeze
in intended or whether the glock demote was caused by a normal unmount.
So it was trying to freeze the file system it's trying to unmount, which
ends up in a deadlock.

This patch adds an additional check to freeze_go_sync so that demotes of the
freeze glock are ignored if they come from the unmount process.

Fixes: 20b3291290 ("gfs2: Fix regression in freeze_go_sync")
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2020-11-25 18:12:08 +01:00
Bob Peterson
778721510e gfs2: check for empty rgrp tree in gfs2_ri_update
If gfs2 tries to mount a (corrupt) file system that has no resource
groups it still tries to set preferences on the first one, which causes
a kernel null pointer dereference. This patch adds a check to function
gfs2_ri_update so this condition is detected and reported back as an
error.

Reported-by: syzbot+e3f23ce40269a4c9053a@syzkaller.appspotmail.com
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2020-11-25 18:10:55 +01:00
Alexander Aring
515b269d5b gfs2: set lockdep subclass for iopen glocks
This patch introduce a new globs attribute to define the subclass of the
glock lockref spinlock. This avoid the following lockdep warning, which
occurs when we lock an inode lock while an iopen lock is held:

============================================
WARNING: possible recursive locking detected
5.10.0-rc3+ #4990 Not tainted
--------------------------------------------
kworker/0:1/12 is trying to acquire lock:
ffff9067d45672d8 (&gl->gl_lockref.lock){+.+.}-{3:3}, at: lockref_get+0x9/0x20

but task is already holding lock:
ffff9067da308588 (&gl->gl_lockref.lock){+.+.}-{3:3}, at: delete_work_func+0x164/0x260

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&gl->gl_lockref.lock);
  lock(&gl->gl_lockref.lock);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

3 locks held by kworker/0:1/12:
 #0: ffff9067c1bfdd38 ((wq_completion)delete_workqueue){+.+.}-{0:0}, at: process_one_work+0x1b7/0x540
 #1: ffffac594006be70 ((work_completion)(&(&gl->gl_delete)->work)){+.+.}-{0:0}, at: process_one_work+0x1b7/0x540
 #2: ffff9067da308588 (&gl->gl_lockref.lock){+.+.}-{3:3}, at: delete_work_func+0x164/0x260

stack backtrace:
CPU: 0 PID: 12 Comm: kworker/0:1 Not tainted 5.10.0-rc3+ #4990
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-2.fc32 04/01/2014
Workqueue: delete_workqueue delete_work_func
Call Trace:
 dump_stack+0x8b/0xb0
 __lock_acquire.cold+0x19e/0x2e3
 lock_acquire+0x150/0x410
 ? lockref_get+0x9/0x20
 _raw_spin_lock+0x27/0x40
 ? lockref_get+0x9/0x20
 lockref_get+0x9/0x20
 delete_work_func+0x188/0x260
 process_one_work+0x237/0x540
 worker_thread+0x4d/0x3b0
 ? process_one_work+0x540/0x540
 kthread+0x127/0x140
 ? __kthread_bind_mask+0x60/0x60
 ret_from_fork+0x22/0x30

Suggested-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2020-11-24 23:45:58 +01:00
Alexander Aring
16e6281b6b gfs2: Fix deadlock dumping resource group glocks
Commit 0e539ca1bb ("gfs2: Fix NULL pointer dereference in gfs2_rgrp_dump")
introduced additional locking in gfs2_rgrp_go_dump, which is also used for
dumping resource group glocks via debugfs.  However, on that code path, the
glock spin lock is already taken in dump_glock, and taking it again in
gfs2_glock2rgrp leads to deadlock.  This can be reproduced with:

  $ mkfs.gfs2 -O -p lock_nolock /dev/FOO
  $ mount /dev/FOO /mnt/foo
  $ touch /mnt/foo/bar
  $ cat /sys/kernel/debug/gfs2/FOO/glocks

Fix that by not taking the glock spin lock inside the go_dump callback.

Fixes: 0e539ca1bb ("gfs2: Fix NULL pointer dereference in gfs2_rgrp_dump")
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2020-11-24 23:45:58 +01:00
Bob Peterson
20b3291290 gfs2: Fix regression in freeze_go_sync
Patch 541656d3a5 ("gfs2: freeze should work on read-only mounts") changed
the check for glock state in function freeze_go_sync() from "gl->gl_state
== LM_ST_SHARED" to "gl->gl_req == LM_ST_EXCLUSIVE".  That's wrong and it
regressed gfs2's freeze/thaw mechanism because it caused only the freezing
node (which requests the glock in EX) to queue freeze work.

All nodes go through this go_sync code path during the freeze to drop their
SHared hold on the freeze glock, allowing the freezing node to acquire it
in EXclusive mode. But all the nodes must freeze access to the file system
locally, so they ALL must queue freeze work. The freeze_work calls
freeze_func, which makes a request to reacquire the freeze glock in SH,
effectively blocking until the thaw from the EX holder. Once thawed, the
freezing node drops its EX hold on the freeze glock, then the (blocked)
freeze_func reacquires the freeze glock in SH again (on all nodes, including
the freezer) so all nodes go back to a thawed state.

This patch changes the check back to gl_state == LM_ST_SHARED like it was
prior to 541656d3a5.

Fixes: 541656d3a5 ("gfs2: freeze should work on read-only mounts")
Cc: stable@vger.kernel.org # v5.8+
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2020-11-18 16:28:11 +01:00
Bob Peterson
4e79e3f08e gfs2: Fix case in which ail writes are done to jdata holes
Patch b2a846dbef ("gfs2: Ignore journal log writes for jdata holes")
tried (unsuccessfully) to fix a case in which writes were done to jdata
blocks, the blocks are sent to the ail list, then a punch_hole or truncate
operation caused the blocks to be freed. In other words, the ail items
are for jdata holes. Before b2a846dbef, the jdata hole caused function
gfs2_block_map to return -EIO, which was eventually interpreted as an
IO error to the journal, and then withdraw.

This patch changes function gfs2_get_block_noalloc, which is only used
for jdata writes, so it returns -ENODATA rather than -EIO, and when
-ENODATA is returned to gfs2_ail1_start_one, the error is ignored.
We can safely ignore it because gfs2_ail1_start_one is only called
when the jdata pages have already been written and truncated, so the
ail1 content no longer applies.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2020-11-12 18:55:20 +01:00
Bob Peterson
d3039c0615 Revert "gfs2: Ignore journal log writes for jdata holes"
This reverts commit b2a846dbef.

That commit changed the behavior of function gfs2_block_map to return
-ENODATA in cases where a hole (IOMAP_HOLE) is encountered and create is
false.  While that fixed the intended problem for jdata, it also broke
other callers of gfs2_block_map such as some jdata block reads.  Before
the patch, an encountered hole would be skipped and the buffer seen as
unmapped by the caller.  The patch changed the behavior to return
-ENODATA, which is interpreted as an error by the caller.

The -ENODATA return code should be restricted to the specific case where
jdata holes are encountered during ail1 writes.  That will be done in a
later patch.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2020-11-12 18:41:57 +01:00
Zhang Qilong
bc923818b1 gfs2: fix possible reference leak in gfs2_check_blk_type
In the fail path of gfs2_check_blk_type, forgetting to call
gfs2_glock_dq_uninit will result in rgd_gh reference leak.

Signed-off-by: Zhang Qilong <zhangqilong3@huawei.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2020-11-12 13:09:07 +01:00
Alexander Aring
da7d554f7c gfs2: Wake up when sd_glock_disposal becomes zero
Commit fc0e38dae6 ("GFS2: Fix glock deallocation race") fixed a
sd_glock_disposal accounting bug by adding a missing atomic_dec
statement, but it failed to wake up sd_glock_wait when that decrement
causes sd_glock_disposal to reach zero.  As a consequence,
gfs2_gl_hash_clear can now run into a 10-minute timeout instead of
being woken up.  Add the missing wakeup.

Fixes: fc0e38dae6 ("GFS2: Fix glock deallocation race")
Cc: stable@vger.kernel.org # v2.6.39+
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2020-11-03 14:39:11 +01:00