Commit Graph

2436 Commits

Author SHA1 Message Date
Linus Torvalds 8418dabd97 Various minor gfs2 cleanups and fixes
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Merge tag 'gfs2-v5.13-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2

Pull gfs2 updates from Andreas Gruenbacher:
 "Various minor gfs2 cleanups and fixes"

* tag 'gfs2-v5.13-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
  gfs2: Clean up gfs2_unstuff_dinode
  gfs2: Unstuff before locking page in gfs2_page_mkwrite
  gfs2: Clean up the error handling in gfs2_page_mkwrite
  gfs2: Fix error handling in init_statfs
  gfs2: Fix underflow in gfs2_page_mkwrite
  gfs2: Use list_move_tail instead of list_del/list_add_tail
  gfs2: Fix do_gfs2_set_flags description
2021-06-29 20:23:08 -07:00
Matthew Wilcox (Oracle) fd7353f88b iomap: use __set_page_dirty_nobuffers
The only difference between iomap_set_page_dirty() and
__set_page_dirty_nobuffers() is that the latter includes a debugging check
that a !Uptodate page has private data.

Link: https://lkml.kernel.org/r/20210615162342.1669332-4-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-29 10:53:48 -07:00
Christoph Hellwig 0af573780b mm: require ->set_page_dirty to be explicitly wired up
Remove the CONFIG_BLOCK default to __set_page_dirty_buffers and just wire
that method up for the missing instances.

[hch@lst.de: ecryptfs: add a ->set_page_dirty cludge]
  Link: https://lkml.kernel.org/r/20210624125250.536369-1-hch@lst.de

Link: https://lkml.kernel.org/r/20210614061512.3966143-4-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Tyler Hicks <code@tyhicks.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-29 10:53:48 -07:00
Andreas Gruenbacher 7a607a41cd gfs2: Clean up gfs2_unstuff_dinode
Split __gfs2_unstuff_inode off from gfs2_unstuff_dinode and clean up the
code a little.  All remaining callers now pass NULL as the page argument
of gfs2_unstuff_dinode, so remove that argument.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-06-29 10:56:51 +02:00
Andreas Gruenbacher 64090cbe4b gfs2: Unstuff before locking page in gfs2_page_mkwrite
In gfs2_page_mkwrite, unstuff inodes before locking the page.  That
way, we won't have to pass in the locked page to gfs2_unstuff_inode,
and gfs2_unstuff_inode can look up and lock the page itself.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-06-29 10:56:51 +02:00
Andreas Gruenbacher 0fc3bcd6b6 gfs2: Clean up the error handling in gfs2_page_mkwrite
We're setting an error number so that block_page_mkwrite_return
translates it into the corresponding VM_FAULT_* code in several places,
but this is getting confusing, so set the VM_FAULT_* codes directly
instead.  (No change in functionality.)

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-06-29 10:56:51 +02:00
Andreas Gruenbacher 5d49d3508b gfs2: Fix error handling in init_statfs
On an error path, init_statfs calls iput(pn) after pn has already been put.
Fix that by setting pn to NULL after the initial iput.

Fixes: 97fd734ba1 ("gfs2: lookup local statfs inodes prior to journal recovery")
Cc: stable@vger.kernel.org # v5.10+
Reported-by: Jing Xiangfeng <jingxiangfeng@huawei.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-06-28 14:30:00 +02:00
Andreas Gruenbacher d3c51c55cb gfs2: Fix underflow in gfs2_page_mkwrite
On filesystems with a block size smaller than PAGE_SIZE and non-empty
files smaller then PAGE_SIZE, gfs2_page_mkwrite could end up allocating
excess blocks beyond the end of the file, similar to fallocate.  This
doesn't make sense; fix it.

Reported-by: Bob Peterson <rpeterso@redhat.com>
Fixes: 184b4e6085 ("gfs2: Fix end-of-file handling in gfs2_page_mkwrite")
Cc: stable@vger.kernel.org # v5.5+
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-06-28 14:13:38 +02:00
Baokun Li 38a618dbf4 gfs2: Use list_move_tail instead of list_del/list_add_tail
Using list_move_tail() instead of list_del() + list_add_tail().

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Baokun Li <libaokun1@huawei.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-06-28 14:13:38 +02:00
Andreas Gruenbacher 0f1616f6df gfs2: Fix do_gfs2_set_flags description
Commit 88b631cbfb ("gfs2: convert to fileattr") changed the argument list
without updating the description.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-06-28 14:13:38 +02:00
Andreas Gruenbacher d5b8145455 Revert "gfs2: Fix mmap locking for write faults"
This reverts commit b7f55d928e.

As explained by Linus in [*], write faults on a mmap region are reads
from a filesysten point of view, so taking the inode glock exclusively
on write faults is incorrect.

Instead, when a page is marked writable, the .page_mkwrite vm operation
will be called, which is where the exclusive lock taking needs to
happen.  I got this wrong because of a broken test case that made me
believe .page_mkwrite isn't getting called when it actually is.

[*] https://lore.kernel.org/lkml/CAHk-=wj8EWr_D65i4oRSj2FTbrc6RdNydNNCGxeabRnwtoU=3Q@mail.gmail.com/

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-06-01 23:16:42 +02:00
Hillf Danton 1ab19c5de4 gfs2: Fix use-after-free in gfs2_glock_shrink_scan
The GLF_LRU flag is checked under lru_lock in gfs2_glock_remove_from_lru() to
remove the glock from the lru list in __gfs2_glock_put().

On the shrink scan path, the same flag is cleared under lru_lock but because
of cond_resched_lock(&lru_lock) in gfs2_dispose_glock_lru(), progress on the
put side can be made without deleting the glock from the lru list.

Keep GLF_LRU across the race window opened by cond_resched_lock(&lru_lock) to
ensure correct behavior on both sides - clear GLF_LRU after list_del under
lru_lock.

Reported-by: syzbot <syzbot+34ba7ddbf3021981a228@syzkaller.appspotmail.com>
Signed-off-by: Hillf Danton <hdanton@sina.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-05-31 12:03:28 +02:00
Andreas Gruenbacher b7f55d928e gfs2: Fix mmap locking for write faults
When a write fault occurs, we need to take the inode glock of the underlying
inode in exclusive mode.  Otherwise, there's no guarantee that the dirty page
will be written back to disk.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-05-21 05:16:38 +02:00
Bob Peterson f5456b5d67 gfs2: Clean up revokes on normal withdraws
Before this patch, the system ail lists were cleaned up if the logd
process withdrew, but on other withdraws, they were not cleaned up.
This included the cleaning up of the revokes as well.

This patch reorganizes things a bit so that all withdraws (not just logd)
clean up the ail lists, including any pending revokes.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-05-20 13:31:37 +02:00
Bob Peterson 865cc3e9cc gfs2: fix a deadlock on withdraw-during-mount
Before this patch, gfs2 would deadlock because of the following
sequence during mount:

mount
   gfs2_fill_super
      gfs2_make_fs_rw <--- Detects IO error with glock
         kthread_stop(sdp->sd_quotad_process);
            <--- Blocked waiting for quotad to finish

logd
   Detects IO error and the need to withdraw
   calls gfs2_withdraw
      gfs2_make_fs_ro
         kthread_stop(sdp->sd_quotad_process);
            <--- Blocked waiting for quotad to finish

gfs2_quotad
   gfs2_statfs_sync
      gfs2_glock_wait <---- Blocked waiting for statfs glock to be granted

glock_work_func
   do_xmote <---Detects IO error, can't release glock: blocked on withdraw
      glops->go_inval
      glock_blocked_by_withdraw
         requeue glock work & exit <--- work requeued, blocked by withdraw

This patch makes a special exception for the statfs system inode glock,
which allows the statfs glock UNLOCK to proceed normally. That allows the
quotad daemon to exit during the withdraw, which allows the logd daemon
to exit during the withdraw, which allows the mount to exit.

Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-05-20 13:31:37 +02:00
Bob Peterson 20265d9a67 gfs2: fix scheduling while atomic bug in glocks
Before this patch, in the unlikely event that gfs2_glock_dq encountered
a withdraw, it would do a wait_on_bit to wait for its journal to be
recovered, but it never released the glock's spin_lock, which caused a
scheduling-while-atomic error.

This patch unlocks the lockref spin_lock before waiting for recovery.

Fixes: 601ef0d52e ("gfs2: Force withdraw to replay journals and wait for it to finish")
Cc: stable@vger.kernel.org # v5.7+
Reported-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-05-20 13:31:37 +02:00
Bob Peterson 4194dec4b4 gfs2: Fix I_NEW check in gfs2_dinode_in
Patch 4a378d8a0d added a new check for I_NEW inodes, but unfortunately
it used the wrong variable, i_flags. This caused GFS2 to withdraw when
gfs2_lookup_by_inum needed to refresh an I_NEW inode. This patch switches
to use the correct variable, i_state.

Fixes: 4a378d8a0d ("gfs2: be careful with inode refresh")
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-05-20 13:31:37 +02:00
Andreas Gruenbacher 43a511c44e gfs2: Prevent direct-I/O write fallback errors from getting lost
When a direct I/O write falls entirely and falls back to buffered I/O and the
buffered I/O fails, the write failed with return value 0 instead of the error
number reported by the buffered I/O. Fix that.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
2021-05-20 13:31:36 +02:00
Matthew Wilcox (Oracle) 7716506ada mm: introduce and use mapping_empty()
Patch series "Remove nrexceptional tracking", v2.

We actually use nrexceptional for very little these days.  It's a minor
pain to keep in sync with nrpages, but the pain becomes much bigger with
the THP patches because we don't know how many indices a shadow entry
occupies.  It's easier to just remove it than keep it accurate.

Also, we save 8 bytes per inode which is nothing to sneeze at; on my
laptop, it would improve shmem_inode_cache from 22 to 23 objects per
16kB, and inode_cache from 26 to 27 objects.  Combined, that saves
a megabyte of memory from a combined usage of 25MB for both caches.
Unfortunately, ext4 doesn't cross a magic boundary, so it doesn't save
any memory for ext4.

This patch (of 4):

Instead of checking the two counters (nrpages and nrexceptional), we can
just check whether i_pages is empty.

Link: https://lkml.kernel.org/r/20201026151849.24232-1-willy@infradead.org
Link: https://lkml.kernel.org/r/20201026151849.24232-2-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Tested-by: Vishal Verma <vishal.l.verma@intel.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-05 11:27:19 -07:00
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
Linus Torvalds a4f7fae101 Merge branch 'miklos.fileattr' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull fileattr conversion updates from Miklos Szeredi via Al Viro:
 "This splits the handling of FS_IOC_[GS]ETFLAGS from ->ioctl() into a
  separate method.

  The interface is reasonably uniform across the filesystems that
  support it and gives nice boilerplate removal"

* 'miklos.fileattr' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (23 commits)
  ovl: remove unneeded ioctls
  fuse: convert to fileattr
  fuse: add internal open/release helpers
  fuse: unsigned open flags
  fuse: move ioctl to separate source file
  vfs: remove unused ioctl helpers
  ubifs: convert to fileattr
  reiserfs: convert to fileattr
  ocfs2: convert to fileattr
  nilfs2: convert to fileattr
  jfs: convert to fileattr
  hfsplus: convert to fileattr
  efivars: convert to fileattr
  xfs: convert to fileattr
  orangefs: convert to fileattr
  gfs2: convert to fileattr
  f2fs: convert to fileattr
  ext4: convert to fileattr
  ext2: convert to fileattr
  btrfs: convert to fileattr
  ...
2021-04-27 11:18:24 -07:00
Linus Torvalds d1466bc583 Merge branch 'work.inode-type-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs inode type handling updates from Al Viro:
 "We should never change the type bits of ->i_mode or the method tables
  (->i_op and ->i_fop) of a live inode.

  Unfortunately, not all filesystems took care to prevent that"

* 'work.inode-type-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  spufs: fix bogosity in S_ISGID handling
  9p: missing chunk of "fs/9p: Don't update file type when updating file attributes"
  openpromfs: don't do unlock_new_inode() until the new inode is set up
  hostfs_mknod(): don't bother with init_special_inode()
  cifs: have cifs_fattr_to_inode() refuse to change type on live inode
  cifs: have ->mkdir() handle race with another client sanely
  do_cifs_create(): don't set ->i_mode of something we had not created
  gfs2: be careful with inode refresh
  ocfs2_inode_lock_update(): make sure we don't change the type bits of i_mode
  orangefs_inode_is_stale(): i_mode type bits do *not* form a bitmap...
  vboxsf: don't allow to change the inode type
  afs: Fix updating of i_mode due to 3rd party change
  ceph: don't allow type or device number to change on non-I_NEW inodes
  ceph: fix up error handling with snapdirs
  new helper: inode_wrong_type()
2021-04-27 10:57:42 -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
Sami Tolvanen 4f0f586bf0 treewide: Change list_sort to use const pointers
list_sort() internally casts the comparison function passed to it
to a different type with constant struct list_head pointers, and
uses this pointer to call the functions, which trips indirect call
Control-Flow Integrity (CFI) checking.

Instead of removing the consts, this change defines the
list_cmp_func_t type and changes the comparison function types of
all list_sort() callers to use const pointers, thus avoiding type
mismatches.

Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20210408182843.1754385-10-samitolvanen@google.com
2021-04-08 16:04:22 -07:00
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
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