clang static analyzer complains that value stored to 'gh' is never read.
The code of this line is useless after commit 0b93bac2
("gfs2: Remove LM_FLAG_PRIORITY flag"). Remove this code to save space.
Signed-off-by: Su Hui <suhui@nfschina.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

In gfs2_put_super(), whether withdrawn or not, the quota should
be cleaned up by gfs2_quota_cleanup().

Otherwise, struct gfs2_sbd will be freed before gfs2_qd_dealloc (rcu
callback) has run for all gfs2_quota_data objects, resulting in
use-after-free.

Also, gfs2_destroy_threads() and gfs2_quota_cleanup() is already called
by gfs2_make_fs_ro(), so in gfs2_put_super(), after calling
gfs2_make_fs_ro(), there is no need to call them again.

Reported-by: syzbot+29c47e9e51895928698c@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=29c47e9e51895928698cSigned-off-by: Juntong Deng <juntong.deng@outlook.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

Commit 0abd1557 added rcu_dereference() for dereferencing ip->i_gl
in gfs2_permission.  This now causes lockdep to complain when
gfs2_permission is called in non-RCU context:

    WARNING: suspicious RCU usage in gfs2_permission

Switch to rcu_dereference_check() and check for the MAY_NOT_BLOCK flag
to shut up lockdep when we know that dereferencing ip->i_gl is safe.

Fixes: 0abd1557 ("gfs2: fix an oops in gfs2_permission")
Reported-by: syzbot+3e5130844b0c0e2b4948@syzkaller.appspotmail.com
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

gfs2 already has optional persistent uuid.

Use that uuid to report f_fsid in statfs(2), same as ext2/ext4/zonefs.

This allows gfs2 to be monitored by fanotify filesystem watch.
for example, with inotify-tools 4.23.8.0, the following command can be
used to watch changes over entire filesystem:

  fsnotifywatch --filesystem /mnt/gfs2
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

For non-static function declarations, external linkage is implied and
the 'extern' keyword isn't needed.  Some static checkers complain about
the overuse of 'extern', so clean up all the function declarations.

In addition, remove 'extern' from the definition of
free_local_statfs_inodes(); it isn't needed there, either.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

Function gfs2_lookup_simple() is used for looking up inodes in the
metadata directory tree, so rename it to gfs2_lookup_meta() to closer
match its purpose.  Clean the function up a little on the way.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

Change gfs2_internal_read() to use folios.  Convert sizes to size_t.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

Change stuffed_readpage() to take a folio instead of a page.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

In gfs2_write_jdata_batch(), to compute the number of blocks, compute
the total size of the folio batch instead of the number of pages it
contains.  Not a functional change.

Note that we don't currently allow mounting filesystems with a block
size bigger than the page size.  We could change that after converting
the page cache to folios.  The page cache would then only contain
block-size or bigger folios, so rounding wouldn't become an issue here.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

Get rid of the generation parameter of gfs2_alloc_blocks(): we only ever
set the generation of the current inode while creating it, so do so
directly.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

Add a metapath_dibh() helper for extracting the inode's buffer head from
a metapath.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

Function print_message() in quota.c doesn't return a meaningful return
value.  Turn it into a void function and stop abusing it for setting
variable error to 0 in gfs2_quota_check().
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

When intializing a struct, all fields that are not explicitly mentioned
are zeroed out already.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

Make sure we don't skip accounting for quota changes with the
quota=account mount option.
Reviewed-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

Header gfs2_ondisk.h defines GFS2_BASIC_BLOCK and GFS2_BASIC_BLOCK_SHIFT
in a misguided attempt to abstract away the fact that sectors on block
devices are 512 or (1 << 9) bytes in size.  Stop using those definitions.

I would be inclinded to remove those definitions altogether, but the
gfs2 user-space tools are using them.

In addition, instead of GFS2_SB(inode)->sd_sb.sb_bsize_shift, simply use
inode->i_blkbits.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Cc: Andrew Price <anprice@redhat.com>

Add a missing initialization of variable ap in setattr_chown().
Without, chown() may be able to bypass quotas.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

In RCU mode, we might race with gfs2_evict_inode(), which zeroes
->i_gl.  Freeing of the object it points to is RCU-delayed, so
if we manage to fetch the pointer before it's been replaced with
NULL, we are fine.  Check if we'd fetched NULL and treat that
as "bail out and tell the caller to get out of RCU mode".
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

When lots of quota changes are made, there may be cases in which an
inode's quota information is increased and then decreased, such as when
blocks are added to a file, then deleted from it. If the timing is
right, function do_qc can add pending quota changes to a transaction,
then later, another call to do_qc can negate those changes, resulting
in a net gain of 0. The quota_change information is recorded in the qc
buffer (and qd element of the inode as well). The buffer is added to the
transaction by the first call to do_qc, but a subsequent call changes
the value from non-zero back to zero. At that point it's too late to
remove the buffer_head from the transaction. Later, when the quota sync
code is called, the zero-change qd element is discovered and flagged as
an assert warning. If the fs is mounted with errors=panic, the kernel
will panic.

This is usually seen when files are truncated and the quota changes are
negated by punch_hole/truncate which uses gfs2_quota_hold and
gfs2_quota_unhold rather than block allocations that use gfs2_quota_lock
and gfs2_quota_unlock which automatically do quota sync.

This patch solves the problem by adding a check to qd_check_sync such
that net-zero quota changes already added to the transaction are no
longer deemed necessary to be synced, and skipped.

In this case references are taken for the qd and the slot from do_qc
so those need to be put. The normal sequence of events for a normal
non-zero quota change is as follows:

gfs2_quota_change
   do_qc
      qd_hold
      slot_hold

Later, when the changes are to be synced:

gfs2_quota_sync
   qd_fish
      qd_check_sync
         gets qd ref via lockref_get_not_dead
   do_sync
      do_qc(QC_SYNC)
         qd_put
	    lockref_put_or_lock
   qd_unlock
      qd_put
         lockref_put_or_lock

In the net-zero change case, we add a check to qd_check_sync so it puts
the qd and slot references acquired in gfs2_quota_change and skip the
unneeded sync.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

During direct reads and writes, the caller is holding the inode glock in
deferred mode, which doesn't allow metadata updates.  However, a previous
change caused callers to update the inode modification time before carrying out
direct writes, which caused the inode glock to be converted to exclusive mode
for the timestamp update, only to be immediately converted back to deferred
mode for the direct write.  This locks out other direct readers and writers
and wreaks havoc on performance.

Fix that by reverting to not updating the inode modification time for direct
writes.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

Those helpers don't add any clarity and are easy to use wrong.  Spell
them out to make more obvious what's happening.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

The limit argument of gfs2_extent_length() is unused.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

Before commit b77b4a48 ("gfs2: Rework freeze / thaw logic"), the
freeze glock was kept around in the glock cache in shared mode without
being actively held while a filesystem is in thawed state.  In that
state, memory pressure could have eventually evicted the freeze glock,
and the freeze_go_demote_ok callback was needed to prevent that from
happening.

With the freeze / thaw rework, the freeze glock is now always actively
held in shared mode while a filesystem is thawed, and the
freeze_go_demote_ok hack is no longer needed.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

When trying to upgrade the iopen glock, gfs2_upgrade_iopen_glock() tries
to take the iopen glock with the LM_FLAG_TRY_1CB flag set before trying
to take it without the LM_FLAG_TRY or LM_FLAG_TRY_1CB flags set.  Both
calls will cause the lock contention bast callbacks to be invoked
throughout the cluster, and we really don't need them to be invoked
twice.  Remove the first LM_FLAG_TRY_1CB call to eliminate unnecessary
dlm traffic.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

Pull gfs2 fixes from Andreas Gruenbacher:

 - Fix another freeze/thaw hang

 - Fix glock cache shrinking

 - Fix the quota=quiet mount option

* tag 'gfs2-v6.6-rc1-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
  gfs2: Fix quota=quiet oversight
  gfs2: fix glock shrinker ref issues
  gfs2: Fix another freeze/thaw hang

Patch eef46ab7 introduced a new gfs2 quota=quiet mount option.
Checks for the new option were added to quota.c, but a check in
gfs2_quota_lock_check() was overlooked.  This patch adds the missing
check.

Fixes: eef46ab7 ("gfs2: Introduce new quota=quiet mount option")
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

Before this patch, function gfs2_scan_glock_lru would only try to free
glocks that had a reference count of 0. But if the reference count ever
got to 0, the glock should have already been freed.

Shrinker function gfs2_dispose_glock_lru checks whether glocks on the
LRU are demote_ok, and if so, tries to demote them. But that's only
possible if the reference count is at least 1.

This patch changes gfs2_scan_glock_lru so it will try to demote and/or
dispose of glocks that have a reference count of 1 and which are either
demotable, or are already unlocked.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

On a thawed filesystem, the freeze glock is held in shared mode.  In
order to initiate a cluster-wide freeze, the node initiating the freeze
drops the freeze glock and grabs it in exclusive mode.  The other nodes
recognize this as contention on the freeze glock; function
freeze_go_callback is invoked.  This indicates to them that they must
freeze the filesystem locally, drop the freeze glock, and then
re-acquire it in shared mode before being able to unfreeze the
filesystem locally.

While a node is trying to re-acquire the freeze glock in shared mode,
additional contention can occur.  In that case, the node must behave in
the same way as above.

Unfortunately, freeze_go_callback() contains a check that causes it to
bail out when the freeze glock isn't held in shared mode.  Fix that to
allow the glock to be unlocked or held in shared mode.

In addition, update a reference to trylock_super() which has been
renamed to super_trylock_shared() in the meantime.

Fixes: b77b4a48 ("gfs2: Rework freeze / thaw logic")
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

Pull x86 fixes from Ingo Molnar:
 "Misc fixes:

   - Fix an UV boot crash

   - Skip spurious ENDBR generation on _THIS_IP_

   - Fix ENDBR use in putuser() asm methods

   - Fix corner case boot crashes on 5-level paging

   - and fix a false positive WARNING on LTO kernels"

* tag 'x86-urgent-2023-09-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/purgatory: Remove LTO flags
  x86/boot/compressed: Reserve more memory for page tables
  x86/ibt: Avoid duplicate ENDBR in __put_user_nocheck*()
  x86/ibt: Suppress spurious ENDBR
  x86/platform/uv: Use alternate source for socket to node data

Pull scheduler fixes from Ingo Molnar:
 "Fix a performance regression on large SMT systems, an Intel SMT4
  balancing bug, and a topology setup bug on (Intel) hybrid processors"

* tag 'sched-urgent-2023-09-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/sched: Restore the SD_ASYM_PACKING flag in the DIE domain
  sched/fair: Fix SMT4 group_smt_balance handling
  sched/fair: Optimize should_we_balance() for large SMT systems

Pull objtool fix from Ingo Molnar:
 "Fix a cold functions related false-positive objtool warning that
  triggers on Clang"

* tag 'objtool-urgent-2023-09-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  objtool: Fix _THIS_IP_ detection for cold functions

Pull WARN fix from Ingo Molnar:
 "Fix a missing preempt-enable in the WARN() slowpath"

* tag 'core-urgent-2023-09-17' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  panic: Reenable preemption in WARN slowpath

The choose_32_64() macros were added to deal with an odd inconsistency
between the 32-bit and 64-bit layout of 'struct stat' way back when in
commit a52dd971 ("vfs: de-crapify "cp_new_stat()" function").

Then a decade later Mikulas noticed that said inconsistency had been a
mistake in the early x86-64 port, and shouldn't have existed in the
first place.  So commit 932aba1e ("stat: fix inconsistency between
struct stat and struct compat_stat") removed the uses of the helpers.

But the helpers remained around, unused.

Get rid of them.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull smb client fixes from Steve French:
 "Three small SMB3 client fixes, one to improve a null check and two
  minor cleanups"

* tag '6.6-rc1-smb3-client-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  smb3: fix some minor typos and repeated words
  smb3: correct places where ENOTSUPP is used instead of preferred EOPNOTSUPP
  smb3: move server check earlier when setting channel sequence number

Pull smb server fixes from Steve French:
 "Two ksmbd server fixes"

* tag '6.6-rc1-ksmbd' of git://git.samba.org/ksmbd:
  ksmbd: fix passing freed memory 'aux_payload_buf'
  ksmbd: remove unneeded mark_inode_dirty in set_info_sec()

Pull ext4 fixes from Ted Ts'o:
 "Regression and bug fixes for ext4"

* tag 'ext4_for_linus-6.6-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: fix rec_len verify error
  ext4: do not let fstrim block system suspend
  ext4: move setting of trimmed bit into ext4_try_to_trim_range()
  jbd2: Fix memory leak in journal_init_common()
  jbd2: Remove page size assumptions
  buffer: Make bh_offset() work for compound pages

-flto* implies -ffunction-sections. With LTO enabled, ld.lld generates
multiple .text sections for purgatory.ro:

  $ readelf -S purgatory.ro  | grep " .text"
    [ 1] .text             PROGBITS         0000000000000000  00000040
    [ 7] .text.purgatory   PROGBITS         0000000000000000  000020e0
    [ 9] .text.warn        PROGBITS         0000000000000000  000021c0
    [13] .text.sha256_upda PROGBITS         0000000000000000  000022f0
    [15] .text.sha224_upda PROGBITS         0000000000000000  00002be0
    [17] .text.sha256_fina PROGBITS         0000000000000000  00002bf0
    [19] .text.sha224_fina PROGBITS         0000000000000000  00002cc0

This causes WARNING from kexec_purgatory_setup_sechdrs():

  WARNING: CPU: 26 PID: 110894 at kernel/kexec_file.c:919
  kexec_load_purgatory+0x37f/0x390

Fix this by disabling LTO for purgatory.

[ AFAICT, x86 is the only arch that supports LTO and purgatory. ]

We could also fix this with an explicit linker script to rejoin .text.*
sections back into .text. However, given the benefit of LTOing purgatory
is small, simply disable the production of more .text.* sections for now.

Fixes: b33fff07 ("x86, build: allow LTO to be selected")
Signed-off-by: Song Liu <song@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Sami Tolvanen <samitolvanen@google.com>
Link: https://lore.kernel.org/r/20230914170138.995606-1-song@kernel.org

The decompressor has a hard limit on the number of page tables it can
allocate. This limit is defined at compile-time and will cause boot
failure if it is reached.

The kernel is very strict and calculates the limit precisely for the
worst-case scenario based on the current configuration. However, it is
easy to forget to adjust the limit when a new use-case arises. The
worst-case scenario is rarely encountered during sanity checks.

In the case of enabling 5-level paging, a use-case was overlooked. The
limit needs to be increased by one to accommodate the additional level.
This oversight went unnoticed until Aaron attempted to run the kernel
via kexec with 5-level paging and unaccepted memory enabled.

Update wost-case calculations to include 5-level paging.

To address this issue, let's allocate some extra space for page tables.
128K should be sufficient for any use-case. The logic can be simplified
by using a single value for all kernel configurations.

[ Also add a warning, should this memory run low - by Dave Hansen. ]

Fixes: 34bbb000 ("x86/boot/compressed: Enable 5-level paging during decompression stage")
Reported-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20230915070221.10266-1-kirill.shutemov@linux.intel.com

Merge tag 'kbuild-fixes-v6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild fixes from Masahiro Yamada:

 - Fix kernel-devel RPM and linux-headers Deb package

 - Fix too long argument list error in 'make modules_install'

* tag 'kbuild-fixes-v6.6' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kbuild: avoid long argument lists in make modules_install
  kbuild: fix kernel-devel RPM package and linux-headers Deb package

Commit 408579cd ("mm: Update do_vmi_align_munmap() return
semantics") seems to have updated one of the callers of do_vmi_munmap()
incorrectly: it used to check for the error case (which didn't
change: negative means error).

That commit changed the check to the success case (which did change:
before that commit, 0 was success, and 1 was "success and lock
downgraded".  After the change, it's always 0 for success, and the lock
will have been released if requested).

This didn't change any actual VM behavior _except_ for memory accounting
when 'VM_ACCOUNT' was set on the vma.  Which made the wrong return value
test fairly subtle, since everything continues to work.

Or rather - it continues to work but the "Committed memory" accounting
goes all wonky (Committed_AS value in /proc/meminfo), and depending on
settings that then causes problems much much later as the VM relies on
bogus statistics for its heuristics.

Revert that one line of the change back to the original logic.

Fixes: 408579cd ("mm: Update do_vmi_align_munmap() return semantics")
Reported-by: Christoph Biedl <linux-kernel.bfrz@manchmal.in-ulm.de>
Reported-bisected-and-tested-by: Michael Labiuk <michael.labiuk@virtuozzo.com>
Cc: Bagas Sanjaya <bagasdotme@gmail.com>
Cc: Liam R. Howlett <Liam.Howlett@oracle.com>
Link: https://lore.kernel.org/all/1694366957@msgid.manchmal.in-ulm.de/Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>