A freezable kernel thread can enter frozen state during freezing by
either calling try_to_freeze() or using wait_event_freezable() and its
variants. So for the following snippet of code in a kernel thread loop:
try_to_freeze();
wait_event_interruptible_timeout();
We can change it to a simple wait_event_freezable_timeout() and then
eliminate a function call.
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
The kernel thread function gfs2_logd() and gfs2_quotad() invoke the
try_to_freeze() in its loop. But all the kernel threads are no-freezable
by default. So if we want to make a kernel thread to be freezable,
we have to invoke set_freezable() explicitly.
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Conventionally, we use the uptodate bit to signal whether a read
encountered an error or not. Use folio_end_read() to set the uptodate
bit on success. Also use filemap_set_wb_err() to communicate the errno
instead of the more heavy-weight mapping_set_error().
Signed-off-by: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Lift the check for the SDF_WITHDRAWING flag out of gfs2_ail1_empty() and
into its callers. This is needed so that gfs2_flush_revokes() can drop
the sd_log_lock spinlock before triggering a withdraw if necessary.
Instead of checking for the SDF_WITHDRAWING flag, use
gfs2_withdrawing(). Also, the low-level code triggering the delayed
withdraw reports when there is a problem, so there is no need to report
that again.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
This function checks whether the filesystem has been been marked to be
withdrawn eventually or has been withdrawn already. Rename this
function to avoid confusing code like checking for gfs2_withdrawing()
when gfs2_withdrawn() has already returned true.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Mark the gfs2_withdrawn(), gfs2_withdrawing(), and
gfs2_withdraw_in_prog() inline functions as likely to return %false.
This allows to get rid of likely() and unlikely() annotations at the
call sites of those functions.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Change gfs2_ail1_empty() to return %true when the ail1 list is empty.
Based on that, make the loop in empty_ail1_list() more obvious.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
... instead of reimplementing it with misguiding name (is_ancestor(x, y)
would normally imply "x is an ancestor of y", not the other way round).
With races, while we are at it...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Add the GL_NOBLOCK flag to the locking requests in gfs2_permission() and
gfs2_drevalidate() when called with the MAY_NOT_BLOCK flag and
LOOKUP_RCU flag, respectively. This will cause the locking requests to
be handled without sleeping if possible. We bail out with -ECHILD if we
can't grant the glock immediately.
Make sure not to dget() + dput() the parent dentry in gfs2_drevalidate()
in LOOKUP_RCU mode; dput() is a sleeping operation.
Signed-off-by: Abhi Das <adas@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Add a GL_NOBLOCK flag for trying to take a glock without sleeping. This
will be used for implementing non-blocking lookup (MAY_NOT_BLOCK in
gfs2_permission, LOOKUP_RCU in gfs2_drevalidate).
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Fix kernel-doc warnings found when using "W=1".
rgrp.c:162: warning: missing initial short description on line:
* gfs2_bit_search
rgrp.c:1200: warning: Function parameter or member 'gl' not described in 'gfs2_rgrp_go_instantiate'
rgrp.c:1200: warning: Excess function parameter 'gh' description in 'gfs2_rgrp_go_instantiate'
rgrp.c:1970: warning: missing initial short description on line:
* gfs2_rgrp_used_recently
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Syzkaller has reported a NULL pointer dereference when accessing
rgd->rd_rgl in gfs2_rgrp_dump(). This can happen when creating
rgd->rd_gl fails in read_rindex_entry(). Add a NULL pointer check in
gfs2_rgrp_dump() to prevent that.
Reported-and-tested-by: syzbot+da0fc229cc1ff4bb2e6d@syzkaller.appspotmail.com
Link: https://syzkaller.appspot.com/bug?extid=da0fc229cc1ff4bb2e6d
Fixes: 72244b6bc7 ("gfs2: improve debug information when lvb mismatches are found")
Signed-off-by: Osama Muhammad <osmtendev@gmail.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Patch series "workload-specific and memory pressure-driven zswap
writeback", v8.
There are currently several issues with zswap writeback:
1. There is only a single global LRU for zswap, making it impossible to
perform worload-specific shrinking - an memcg under memory pressure
cannot determine which pages in the pool it owns, and often ends up
writing pages from other memcgs. This issue has been previously
observed in practice and mitigated by simply disabling
memcg-initiated shrinking:
https://lore.kernel.org/all/20230530232435.3097106-1-nphamcs@gmail.com/T/#u
But this solution leaves a lot to be desired, as we still do not
have an avenue for an memcg to free up its own memory locked up in
the zswap pool.
2. We only shrink the zswap pool when the user-defined limit is hit.
This means that if we set the limit too high, cold data that are
unlikely to be used again will reside in the pool, wasting precious
memory. It is hard to predict how much zswap space will be needed
ahead of time, as this depends on the workload (specifically, on
factors such as memory access patterns and compressibility of the
memory pages).
This patch series solves these issues by separating the global zswap LRU
into per-memcg and per-NUMA LRUs, and performs workload-specific (i.e
memcg- and NUMA-aware) zswap writeback under memory pressure. The new
shrinker does not have any parameter that must be tuned by the user, and
can be opted in or out on a per-memcg basis.
As a proof of concept, we ran the following synthetic benchmark: build the
linux kernel in a memory-limited cgroup, and allocate some cold data in
tmpfs to see if the shrinker could write them out and improved the overall
performance. Depending on the amount of cold data generated, we observe
from 14% to 35% reduction in kernel CPU time used in the kernel builds.
This patch (of 6):
The interface of list_lru is based on the assumption that the list node
and the data it represents belong to the same allocated on the correct
node/memcg. While this assumption is valid for existing slab objects LRU
such as dentries and inodes, it is undocumented, and rather inflexible for
certain potential list_lru users (such as the upcoming zswap shrinker and
the THP shrinker). It has caused us a lot of issues during our
development.
This patch changes list_lru interface so that the caller must explicitly
specify numa node and memcg when adding and removing objects. The old
list_lru_add() and list_lru_del() are renamed to list_lru_add_obj() and
list_lru_del_obj(), respectively.
It also extends the list_lru API with a new function, list_lru_putback,
which undoes a previous list_lru_isolate call. Unlike list_lru_add, it
does not increment the LRU node count (as list_lru_isolate does not
decrement the node count). list_lru_putback also allows for explicit
memcg and NUMA node selection.
Link: https://lkml.kernel.org/r/20231130194023.4102148-1-nphamcs@gmail.com
Link: https://lkml.kernel.org/r/20231130194023.4102148-2-nphamcs@gmail.com
Signed-off-by: Nhat Pham <nphamcs@gmail.com>
Suggested-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Tested-by: Bagas Sanjaya <bagasdotme@gmail.com>
Cc: Chris Li <chrisl@kernel.org>
Cc: Dan Streetman <ddstreet@ieee.org>
Cc: Domenico Cerasuolo <cerasuolodomenico@gmail.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Seth Jennings <sjenning@redhat.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Vitaly Wool <vitaly.wool@konsulko.com>
Cc: Yosry Ahmed <yosryahmed@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
There were already assertions that we were not passing a tail page to
error_remove_page(), so make the compiler enforce that by converting
everything to pass and use a folio.
Link: https://lkml.kernel.org/r/20231117161447.2461643-7-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Naoya Horiguchi <naoya.horiguchi@nec.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Use folio_fill_tail() to implement the unstuffing and folio_end_read() to
simultaneously mark the folio uptodate and unlock it. Unifies a couple of
code paths.
Link: https://lkml.kernel.org/r/20231107212643.3490372-4-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
Cc: Andreas Dilger <adilger.kernel@dilger.ca>
Cc: Darrick J. Wong <djwong@kernel.org>
Cc: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
It is hard to find where mapping->private_lock, mapping->private_list and
mapping->private_data are used, due to private_XXX being a relatively
common name for variables and structure members in the kernel. To fit
with other members of struct address_space, rename them all to have an
i_ prefix. Tested with an allmodconfig build.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Link: https://lore.kernel.org/r/20231117215823.2821906-1-willy@infradead.org
Acked-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
This patch is activating the EXPORT_OP_ASYNC_LOCK export flag to
signal lockd that both filesystems are able to handle async lock
requests. The cluster filesystems gfs2 and ocfs2 will redirect their
lock requests to DLMs plock implementation that can handle async lock
requests.
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: David Teigland <teigland@redhat.com>
- Don't update inode timestamps for direct writes (performance regression fix).
- Skip no-op quota records instead of panicing.
- Fix a RCU race in gfs2_permission().
- Various other smaller fixes and cleanups all over the place.
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Merge tag 'gfs2-v6.6-rc2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2
Pull gfs2 updates from Andreas Gruenbacher:
- Don't update inode timestamps for direct writes (performance
regression fix)
- Skip no-op quota records instead of panicing
- Fix a RCU race in gfs2_permission()
- Various other smaller fixes and cleanups all over the place
* tag 'gfs2-v6.6-rc2-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2: (24 commits)
gfs2: don't withdraw if init_threads() got interrupted
gfs2: remove dead code in add_to_queue
gfs2: Fix slab-use-after-free in gfs2_qd_dealloc
gfs2: Silence "suspicious RCU usage in gfs2_permission" warning
gfs2: fs: derive f_fsid from s_uuid
gfs2: No longer use 'extern' in function declarations
gfs2: Rename gfs2_lookup_{ simple => meta }
gfs2: Convert gfs2_internal_read to folios
gfs2: Convert stuffed_readpage to folios
gfs2: Minor gfs2_write_jdata_batch PAGE_SIZE cleanup
gfs2: Get rid of gfs2_alloc_blocks generation parameter
gfs2: Add metapath_dibh helper
gfs2: Clean up quota.c:print_message
gfs2: Clean up gfs2_alloc_parms initializers
gfs2: Two quota=account mode fixes
gfs2: Stop using GFS2_BASIC_BLOCK and GFS2_BASIC_BLOCK_SHIFT
gfs2: setattr_chown: Add missing initialization
gfs2: fix an oops in gfs2_permission
gfs2: ignore negated quota changes
gfs2: Don't update inode timestamps for direct writes
...
In gfs2_fill_super(), when mounting a gfs2 filesystem is interrupted,
kthread_create() can return -EINTR. When that happens, we roll back
what has already been done and abort the mount.
Since commit 62dd0f98a0 ("gfs2: Flag a withdraw if init_threads()
fails), we are calling gfs2_withdraw_delayed() in gfs2_fill_super();
first via gfs2_make_fs_rw(), then directly. But gfs2_withdraw_delayed()
only marks the filesystem as withdrawing and relies on a caller further
up the stack to do the actual withdraw, which doesn't exist in the
gfs2_fill_super() case. Because the filesystem is marked as withdrawing
/ withdrawn, function gfs2_lm_unmount() doesn't release the dlm
lockspace, so when we try to mount that filesystem again, we get:
gfs2: fsid=gohan:gohan0: Trying to join cluster "lock_dlm", "gohan:gohan0"
gfs2: fsid=gohan:gohan0: dlm_new_lockspace error -17
Since commit b77b4a4815 ("gfs2: Rework freeze / thaw logic"), the
deadlock this gfs2_withdraw_delayed() call was supposed to work around
cannot occur anymore because freeze_go_callback() won't take the
sb->s_umount semaphore unconditionally anymore, so we can get rid of the
gfs2_withdraw_delayed() in gfs2_fill_super() entirely.
Reported-by: Alexander Aring <aahringo@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Cc: stable@vger.kernel.org # v6.5+
clang static analyzer complains that value stored to 'gh' is never read.
The code of this line is useless after commit 0b93bac227
("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=29c47e9e51895928698c
Signed-off-by: Juntong Deng <juntong.deng@outlook.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Commit 0abd1557e2 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: 0abd1557e2 ("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>
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>
there's little I can say which isn't in the individual changelogs.
The lengthier patch series are
- "kdump: use generic functions to simplify crashkernel reservation in
arch", from Baoquan He. This is mainly cleanups and consolidation of
the "crashkernel=" kernel parameter handling.
- After much discussion, David Laight's "minmax: Relax type checks in
min() and max()" is here. Hopefully reduces some typecasting and the
use of min_t() and max_t().
- A group of patches from Oleg Nesterov which clean up and slightly fix
our handling of reads from /proc/PID/task/... and which remove
task_struct.therad_group.
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Merge tag 'mm-nonmm-stable-2023-11-02-14-08' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull non-MM updates from Andrew Morton:
"As usual, lots of singleton and doubleton patches all over the tree
and there's little I can say which isn't in the individual changelogs.
The lengthier patch series are
- 'kdump: use generic functions to simplify crashkernel reservation
in arch', from Baoquan He. This is mainly cleanups and
consolidation of the 'crashkernel=' kernel parameter handling
- After much discussion, David Laight's 'minmax: Relax type checks in
min() and max()' is here. Hopefully reduces some typecasting and
the use of min_t() and max_t()
- A group of patches from Oleg Nesterov which clean up and slightly
fix our handling of reads from /proc/PID/task/... and which remove
task_struct.thread_group"
* tag 'mm-nonmm-stable-2023-11-02-14-08' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (64 commits)
scripts/gdb/vmalloc: disable on no-MMU
scripts/gdb: fix usage of MOD_TEXT not defined when CONFIG_MODULES=n
.mailmap: add address mapping for Tomeu Vizoso
mailmap: update email address for Claudiu Beznea
tools/testing/selftests/mm/run_vmtests.sh: lower the ptrace permissions
.mailmap: map Benjamin Poirier's address
scripts/gdb: add lx_current support for riscv
ocfs2: fix a spelling typo in comment
proc: test ProtectionKey in proc-empty-vm test
proc: fix proc-empty-vm test with vsyscall
fs/proc/base.c: remove unneeded semicolon
do_io_accounting: use sig->stats_lock
do_io_accounting: use __for_each_thread()
ocfs2: replace BUG_ON() at ocfs2_num_free_extents() with ocfs2_error()
ocfs2: fix a typo in a comment
scripts/show_delta: add __main__ judgement before main code
treewide: mark stuff as __ro_after_init
fs: ocfs2: check status values
proc: test /proc/${pid}/statm
compiler.h: move __is_constexpr() to compiler.h
...
included in this merge do the following:
- Kemeng Shi has contributed some compation maintenance work in the
series "Fixes and cleanups to compaction".
- Joel Fernandes has a patchset ("Optimize mremap during mutual
alignment within PMD") which fixes an obscure issue with mremap()'s
pagetable handling during a subsequent exec(), based upon an
implementation which Linus suggested.
- More DAMON/DAMOS maintenance and feature work from SeongJae Park i the
following patch series:
mm/damon: misc fixups for documents, comments and its tracepoint
mm/damon: add a tracepoint for damos apply target regions
mm/damon: provide pseudo-moving sum based access rate
mm/damon: implement DAMOS apply intervals
mm/damon/core-test: Fix memory leaks in core-test
mm/damon/sysfs-schemes: Do DAMOS tried regions update for only one apply interval
- In the series "Do not try to access unaccepted memory" Adrian Hunter
provides some fixups for the recently-added "unaccepted memory' feature.
To increase the feature's checking coverage. "Plug a few gaps where
RAM is exposed without checking if it is unaccepted memory".
- In the series "cleanups for lockless slab shrink" Qi Zheng has done
some maintenance work which is preparation for the lockless slab
shrinking code.
- Qi Zheng has redone the earlier (and reverted) attempt to make slab
shrinking lockless in the series "use refcount+RCU method to implement
lockless slab shrink".
- David Hildenbrand contributes some maintenance work for the rmap code
in the series "Anon rmap cleanups".
- Kefeng Wang does more folio conversions and some maintenance work in
the migration code. Series "mm: migrate: more folio conversion and
unification".
- Matthew Wilcox has fixed an issue in the buffer_head code which was
causing long stalls under some heavy memory/IO loads. Some cleanups
were added on the way. Series "Add and use bdev_getblk()".
- In the series "Use nth_page() in place of direct struct page
manipulation" Zi Yan has fixed a potential issue with the direct
manipulation of hugetlb page frames.
- In the series "mm: hugetlb: Skip initialization of gigantic tail
struct pages if freed by HVO" has improved our handling of gigantic
pages in the hugetlb vmmemmep optimizaton code. This provides
significant boot time improvements when significant amounts of gigantic
pages are in use.
- Matthew Wilcox has sent the series "Small hugetlb cleanups" - code
rationalization and folio conversions in the hugetlb code.
- Yin Fengwei has improved mlock()'s handling of large folios in the
series "support large folio for mlock"
- In the series "Expose swapcache stat for memcg v1" Liu Shixin has
added statistics for memcg v1 users which are available (and useful)
under memcg v2.
- Florent Revest has enhanced the MDWE (Memory-Deny-Write-Executable)
prctl so that userspace may direct the kernel to not automatically
propagate the denial to child processes. The series is named "MDWE
without inheritance".
- Kefeng Wang has provided the series "mm: convert numa balancing
functions to use a folio" which does what it says.
- In the series "mm/ksm: add fork-exec support for prctl" Stefan Roesch
makes is possible for a process to propagate KSM treatment across
exec().
- Huang Ying has enhanced memory tiering's calculation of memory
distances. This is used to permit the dax/kmem driver to use "high
bandwidth memory" in addition to Optane Data Center Persistent Memory
Modules (DCPMM). The series is named "memory tiering: calculate
abstract distance based on ACPI HMAT"
- In the series "Smart scanning mode for KSM" Stefan Roesch has
optimized KSM by teaching it to retain and use some historical
information from previous scans.
- Yosry Ahmed has fixed some inconsistencies in memcg statistics in the
series "mm: memcg: fix tracking of pending stats updates values".
- In the series "Implement IOCTL to get and optionally clear info about
PTEs" Peter Xu has added an ioctl to /proc/<pid>/pagemap which permits
us to atomically read-then-clear page softdirty state. This is mainly
used by CRIU.
- Hugh Dickins contributed the series "shmem,tmpfs: general maintenance"
- a bunch of relatively minor maintenance tweaks to this code.
- Matthew Wilcox has increased the use of the VMA lock over file-backed
page faults in the series "Handle more faults under the VMA lock". Some
rationalizations of the fault path became possible as a result.
- In the series "mm/rmap: convert page_move_anon_rmap() to
folio_move_anon_rmap()" David Hildenbrand has implemented some cleanups
and folio conversions.
- In the series "various improvements to the GUP interface" Lorenzo
Stoakes has simplified and improved the GUP interface with an eye to
providing groundwork for future improvements.
- Andrey Konovalov has sent along the series "kasan: assorted fixes and
improvements" which does those things.
- Some page allocator maintenance work from Kemeng Shi in the series
"Two minor cleanups to break_down_buddy_pages".
- In thes series "New selftest for mm" Breno Leitao has developed
another MM self test which tickles a race we had between madvise() and
page faults.
- In the series "Add folio_end_read" Matthew Wilcox provides cleanups
and an optimization to the core pagecache code.
- Nhat Pham has added memcg accounting for hugetlb memory in the series
"hugetlb memcg accounting".
- Cleanups and rationalizations to the pagemap code from Lorenzo
Stoakes, in the series "Abstract vma_merge() and split_vma()".
- Audra Mitchell has fixed issues in the procfs page_owner code's new
timestamping feature which was causing some misbehaviours. In the
series "Fix page_owner's use of free timestamps".
- Lorenzo Stoakes has fixed the handling of new mappings of sealed files
in the series "permit write-sealed memfd read-only shared mappings".
- Mike Kravetz has optimized the hugetlb vmemmap optimization in the
series "Batch hugetlb vmemmap modification operations".
- Some buffer_head folio conversions and cleanups from Matthew Wilcox in
the series "Finish the create_empty_buffers() transition".
- As a page allocator performance optimization Huang Ying has added
automatic tuning to the allocator's per-cpu-pages feature, in the series
"mm: PCP high auto-tuning".
- Roman Gushchin has contributed the patchset "mm: improve performance
of accounted kernel memory allocations" which improves their performance
by ~30% as measured by a micro-benchmark.
- folio conversions from Kefeng Wang in the series "mm: convert page
cpupid functions to folios".
- Some kmemleak fixups in Liu Shixin's series "Some bugfix about
kmemleak".
- Qi Zheng has improved our handling of memoryless nodes by keeping them
off the allocation fallback list. This is done in the series "handle
memoryless nodes more appropriately".
- khugepaged conversions from Vishal Moola in the series "Some
khugepaged folio conversions".
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Merge tag 'mm-stable-2023-11-01-14-33' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull MM updates from Andrew Morton:
"Many singleton patches against the MM code. The patch series which are
included in this merge do the following:
- Kemeng Shi has contributed some compation maintenance work in the
series 'Fixes and cleanups to compaction'
- Joel Fernandes has a patchset ('Optimize mremap during mutual
alignment within PMD') which fixes an obscure issue with mremap()'s
pagetable handling during a subsequent exec(), based upon an
implementation which Linus suggested
- More DAMON/DAMOS maintenance and feature work from SeongJae Park i
the following patch series:
mm/damon: misc fixups for documents, comments and its tracepoint
mm/damon: add a tracepoint for damos apply target regions
mm/damon: provide pseudo-moving sum based access rate
mm/damon: implement DAMOS apply intervals
mm/damon/core-test: Fix memory leaks in core-test
mm/damon/sysfs-schemes: Do DAMOS tried regions update for only one apply interval
- In the series 'Do not try to access unaccepted memory' Adrian
Hunter provides some fixups for the recently-added 'unaccepted
memory' feature. To increase the feature's checking coverage. 'Plug
a few gaps where RAM is exposed without checking if it is
unaccepted memory'
- In the series 'cleanups for lockless slab shrink' Qi Zheng has done
some maintenance work which is preparation for the lockless slab
shrinking code
- Qi Zheng has redone the earlier (and reverted) attempt to make slab
shrinking lockless in the series 'use refcount+RCU method to
implement lockless slab shrink'
- David Hildenbrand contributes some maintenance work for the rmap
code in the series 'Anon rmap cleanups'
- Kefeng Wang does more folio conversions and some maintenance work
in the migration code. Series 'mm: migrate: more folio conversion
and unification'
- Matthew Wilcox has fixed an issue in the buffer_head code which was
causing long stalls under some heavy memory/IO loads. Some cleanups
were added on the way. Series 'Add and use bdev_getblk()'
- In the series 'Use nth_page() in place of direct struct page
manipulation' Zi Yan has fixed a potential issue with the direct
manipulation of hugetlb page frames
- In the series 'mm: hugetlb: Skip initialization of gigantic tail
struct pages if freed by HVO' has improved our handling of gigantic
pages in the hugetlb vmmemmep optimizaton code. This provides
significant boot time improvements when significant amounts of
gigantic pages are in use
- Matthew Wilcox has sent the series 'Small hugetlb cleanups' - code
rationalization and folio conversions in the hugetlb code
- Yin Fengwei has improved mlock()'s handling of large folios in the
series 'support large folio for mlock'
- In the series 'Expose swapcache stat for memcg v1' Liu Shixin has
added statistics for memcg v1 users which are available (and
useful) under memcg v2
- Florent Revest has enhanced the MDWE (Memory-Deny-Write-Executable)
prctl so that userspace may direct the kernel to not automatically
propagate the denial to child processes. The series is named 'MDWE
without inheritance'
- Kefeng Wang has provided the series 'mm: convert numa balancing
functions to use a folio' which does what it says
- In the series 'mm/ksm: add fork-exec support for prctl' Stefan
Roesch makes is possible for a process to propagate KSM treatment
across exec()
- Huang Ying has enhanced memory tiering's calculation of memory
distances. This is used to permit the dax/kmem driver to use 'high
bandwidth memory' in addition to Optane Data Center Persistent
Memory Modules (DCPMM). The series is named 'memory tiering:
calculate abstract distance based on ACPI HMAT'
- In the series 'Smart scanning mode for KSM' Stefan Roesch has
optimized KSM by teaching it to retain and use some historical
information from previous scans
- Yosry Ahmed has fixed some inconsistencies in memcg statistics in
the series 'mm: memcg: fix tracking of pending stats updates
values'
- In the series 'Implement IOCTL to get and optionally clear info
about PTEs' Peter Xu has added an ioctl to /proc/<pid>/pagemap
which permits us to atomically read-then-clear page softdirty
state. This is mainly used by CRIU
- Hugh Dickins contributed the series 'shmem,tmpfs: general
maintenance', a bunch of relatively minor maintenance tweaks to
this code
- Matthew Wilcox has increased the use of the VMA lock over
file-backed page faults in the series 'Handle more faults under the
VMA lock'. Some rationalizations of the fault path became possible
as a result
- In the series 'mm/rmap: convert page_move_anon_rmap() to
folio_move_anon_rmap()' David Hildenbrand has implemented some
cleanups and folio conversions
- In the series 'various improvements to the GUP interface' Lorenzo
Stoakes has simplified and improved the GUP interface with an eye
to providing groundwork for future improvements
- Andrey Konovalov has sent along the series 'kasan: assorted fixes
and improvements' which does those things
- Some page allocator maintenance work from Kemeng Shi in the series
'Two minor cleanups to break_down_buddy_pages'
- In thes series 'New selftest for mm' Breno Leitao has developed
another MM self test which tickles a race we had between madvise()
and page faults
- In the series 'Add folio_end_read' Matthew Wilcox provides cleanups
and an optimization to the core pagecache code
- Nhat Pham has added memcg accounting for hugetlb memory in the
series 'hugetlb memcg accounting'
- Cleanups and rationalizations to the pagemap code from Lorenzo
Stoakes, in the series 'Abstract vma_merge() and split_vma()'
- Audra Mitchell has fixed issues in the procfs page_owner code's new
timestamping feature which was causing some misbehaviours. In the
series 'Fix page_owner's use of free timestamps'
- Lorenzo Stoakes has fixed the handling of new mappings of sealed
files in the series 'permit write-sealed memfd read-only shared
mappings'
- Mike Kravetz has optimized the hugetlb vmemmap optimization in the
series 'Batch hugetlb vmemmap modification operations'
- Some buffer_head folio conversions and cleanups from Matthew Wilcox
in the series 'Finish the create_empty_buffers() transition'
- As a page allocator performance optimization Huang Ying has added
automatic tuning to the allocator's per-cpu-pages feature, in the
series 'mm: PCP high auto-tuning'
- Roman Gushchin has contributed the patchset 'mm: improve
performance of accounted kernel memory allocations' which improves
their performance by ~30% as measured by a micro-benchmark
- folio conversions from Kefeng Wang in the series 'mm: convert page
cpupid functions to folios'
- Some kmemleak fixups in Liu Shixin's series 'Some bugfix about
kmemleak'
- Qi Zheng has improved our handling of memoryless nodes by keeping
them off the allocation fallback list. This is done in the series
'handle memoryless nodes more appropriately'
- khugepaged conversions from Vishal Moola in the series 'Some
khugepaged folio conversions'"
[ bcachefs conflicts with the dynamically allocated shrinkers have been
resolved as per Stephen Rothwell in
https://lore.kernel.org/all/20230913093553.4290421e@canb.auug.org.au/
with help from Qi Zheng.
The clone3 test filtering conflict was half-arsed by yours truly ]
* tag 'mm-stable-2023-11-01-14-33' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (406 commits)
mm/damon/sysfs: update monitoring target regions for online input commit
mm/damon/sysfs: remove requested targets when online-commit inputs
selftests: add a sanity check for zswap
Documentation: maple_tree: fix word spelling error
mm/vmalloc: fix the unchecked dereference warning in vread_iter()
zswap: export compression failure stats
Documentation: ubsan: drop "the" from article title
mempolicy: migration attempt to match interleave nodes
mempolicy: mmap_lock is not needed while migrating folios
mempolicy: alloc_pages_mpol() for NUMA policy without vma
mm: add page_rmappable_folio() wrapper
mempolicy: remove confusing MPOL_MF_LAZY dead code
mempolicy: mpol_shared_policy_init() without pseudo-vma
mempolicy trivia: use pgoff_t in shared mempolicy tree
mempolicy trivia: slightly more consistent naming
mempolicy trivia: delete those ancient pr_debug()s
mempolicy: fix migrate_pages(2) syscall return nr_failed
kernfs: drop shared NUMA mempolicy hooks
hugetlbfs: drop shared NUMA mempolicy pretence
mm/damon/sysfs-test: add a unit test for damon_sysfs_set_targets()
...
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>
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Merge tag 'vfs-6.7.ctime' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs
Pull vfs inode time accessor updates from Christian Brauner:
"This finishes the conversion of all inode time fields to accessor
functions as discussed on list. Changing timestamps manually as we
used to do before is error prone. Using accessors function makes this
robust.
It does not contain the switch of the time fields to discrete 64 bit
integers to replace struct timespec and free up space in struct inode.
But after this, the switch can be trivially made and the patch should
only affect the vfs if we decide to do it"
* tag 'vfs-6.7.ctime' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs: (86 commits)
fs: rename inode i_atime and i_mtime fields
security: convert to new timestamp accessors
selinux: convert to new timestamp accessors
apparmor: convert to new timestamp accessors
sunrpc: convert to new timestamp accessors
mm: convert to new timestamp accessors
bpf: convert to new timestamp accessors
ipc: convert to new timestamp accessors
linux: convert to new timestamp accessors
zonefs: convert to new timestamp accessors
xfs: convert to new timestamp accessors
vboxsf: convert to new timestamp accessors
ufs: convert to new timestamp accessors
udf: convert to new timestamp accessors
ubifs: convert to new timestamp accessors
tracefs: convert to new timestamp accessors
sysv: convert to new timestamp accessors
squashfs: convert to new timestamp accessors
server: convert to new timestamp accessors
client: convert to new timestamp accessors
...
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Merge tag 'vfs-6.7.xattr' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs
Pull vfs xattr updates from Christian Brauner:
"The 's_xattr' field of 'struct super_block' currently requires a
mutable table of 'struct xattr_handler' entries (although each handler
itself is const). However, no code in vfs actually modifies the
tables.
This changes the type of 's_xattr' to allow const tables, and modifies
existing file systems to move their tables to .rodata. This is
desirable because these tables contain entries with function pointers
in them; moving them to .rodata makes it considerably less likely to
be modified accidentally or maliciously at runtime"
* tag 'vfs-6.7.xattr' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs: (30 commits)
const_structs.checkpatch: add xattr_handler
net: move sockfs_xattr_handlers to .rodata
shmem: move shmem_xattr_handlers to .rodata
overlayfs: move xattr tables to .rodata
xfs: move xfs_xattr_handlers to .rodata
ubifs: move ubifs_xattr_handlers to .rodata
squashfs: move squashfs_xattr_handlers to .rodata
smb: move cifs_xattr_handlers to .rodata
reiserfs: move reiserfs_xattr_handlers to .rodata
orangefs: move orangefs_xattr_handlers to .rodata
ocfs2: move ocfs2_xattr_handlers and ocfs2_xattr_handler_map to .rodata
ntfs3: move ntfs_xattr_handlers to .rodata
nfs: move nfs4_xattr_handlers to .rodata
kernfs: move kernfs_xattr_handlers to .rodata
jfs: move jfs_xattr_handlers to .rodata
jffs2: move jffs2_xattr_handlers to .rodata
hfsplus: move hfsplus_xattr_handlers to .rodata
hfs: move hfs_xattr_handlers to .rodata
gfs2: move gfs2_xattr_handlers_max to .rodata
fuse: move fuse_xattr_handlers to .rodata
...
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Merge tag 'vfs-6.7.misc' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs
Pull misc vfs updates from Christian Brauner:
"This contains the usual miscellaneous features, cleanups, and fixes
for vfs and individual fses.
Features:
- Rename and export helpers that get write access to a mount. They
are used in overlayfs to get write access to the upper mount.
- Print the pretty name of the root device on boot failure. This
helps in scenarios where we would usually only print
"unknown-block(1,2)".
- Add an internal SB_I_NOUMASK flag. This is another part in the
endless POSIX ACL saga in a way.
When POSIX ACLs are enabled via SB_POSIXACL the vfs cannot strip
the umask because if the relevant inode has POSIX ACLs set it might
take the umask from there. But if the inode doesn't have any POSIX
ACLs set then we apply the umask in the filesytem itself. So we end
up with:
(1) no SB_POSIXACL -> strip umask in vfs
(2) SB_POSIXACL -> strip umask in filesystem
The umask semantics associated with SB_POSIXACL allowed filesystems
that don't even support POSIX ACLs at all to raise SB_POSIXACL
purely to avoid umask stripping. That specifically means NFS v4 and
Overlayfs. NFS v4 does it because it delegates this to the server
and Overlayfs because it needs to delegate umask stripping to the
upper filesystem, i.e., the filesystem used as the writable layer.
This went so far that SB_POSIXACL is raised eve on kernels that
don't even have POSIX ACL support at all.
Stop this blatant abuse and add SB_I_NOUMASK which is an internal
superblock flag that filesystems can raise to opt out of umask
handling. That should really only be the two mentioned above. It's
not that we want any filesystems to do this. Ideally we have all
umask handling always in the vfs.
- Make overlayfs use SB_I_NOUMASK too.
- Now that we have SB_I_NOUMASK, stop checking for SB_POSIXACL in
IS_POSIXACL() if the kernel doesn't have support for it. This is a
very old patch but it's only possible to do this now with the wider
cleanup that was done.
- Follow-up work on fake path handling from last cycle. Citing mostly
from Amir:
When overlayfs was first merged, overlayfs files of regular files
and directories, the ones that are installed in file table, had a
"fake" path, namely, f_path is the overlayfs path and f_inode is
the "real" inode on the underlying filesystem.
In v6.5, we took another small step by introducing of the
backing_file container and the file_real_path() helper. This change
allowed vfs and filesystem code to get the "real" path of an
overlayfs backing file. With this change, we were able to make
fsnotify work correctly and report events on the "real" filesystem
objects that were accessed via overlayfs.
This method works fine, but it still leaves the vfs vulnerable to
new code that is not aware of files with fake path. A recent
example is commit db1d1e8b98 ("IMA: use vfs_getattr_nosec to get
the i_version"). This commit uses direct referencing to f_path in
IMA code that otherwise uses file_inode() and file_dentry() to
reference the filesystem objects that it is measuring.
This contains work to switch things around: instead of having
filesystem code opt-in to get the "real" path, have generic code
opt-in for the "fake" path in the few places that it is needed.
Is it far more likely that new filesystems code that does not use
the file_dentry() and file_real_path() helpers will end up causing
crashes or averting LSM/audit rules if we keep the "fake" path
exposed by default.
This change already makes file_dentry() moot, but for now we did
not change this helper just added a WARN_ON() in ovl_d_real() to
catch if we have made any wrong assumptions.
After the dust settles on this change, we can make file_dentry() a
plain accessor and we can drop the inode argument to ->d_real().
- Switch struct file to SLAB_TYPESAFE_BY_RCU. This looks like a small
change but it really isn't and I would like to see everyone on
their tippie toes for any possible bugs from this work.
Essentially we've been doing most of what SLAB_TYPESAFE_BY_RCU for
files since a very long time because of the nasty interactions
between the SCM_RIGHTS file descriptor garbage collection. So
extending it makes a lot of sense but it is a subtle change. There
are almost no places that fiddle with file rcu semantics directly
and the ones that did mess around with struct file internal under
rcu have been made to stop doing that because it really was always
dodgy.
I forgot to put in the link tag for this change and the discussion
in the commit so adding it into the merge message:
https://lore.kernel.org/r/20230926162228.68666-1-mjguzik@gmail.com
Cleanups:
- Various smaller pipe cleanups including the removal of a spin lock
that was only used to protect against writes without pipe_lock()
from O_NOTIFICATION_PIPE aka watch queues. As that was never
implemented remove the additional locking from pipe_write().
- Annotate struct watch_filter with the new __counted_by attribute.
- Clarify do_unlinkat() cleanup so that it doesn't look like an extra
iput() is done that would cause issues.
- Simplify file cleanup when the file has never been opened.
- Use module helper instead of open-coding it.
- Predict error unlikely for stale retry.
- Use WRITE_ONCE() for mount expiry field instead of just commenting
that one hopes the compiler doesn't get smart.
Fixes:
- Fix readahead on block devices.
- Fix writeback when layztime is enabled and inodes whose timestamp
is the only thing that changed reside on wb->b_dirty_time. This
caused excessively large zombie memory cgroup when lazytime was
enabled as such inodes weren't handled fast enough.
- Convert BUG_ON() to WARN_ON_ONCE() in open_last_lookups()"
* tag 'vfs-6.7.misc' of gitolite.kernel.org:pub/scm/linux/kernel/git/vfs/vfs: (26 commits)
file, i915: fix file reference for mmap_singleton()
vfs: Convert BUG_ON to WARN_ON_ONCE in open_last_lookups
writeback, cgroup: switch inodes with dirty timestamps to release dying cgwbs
chardev: Simplify usage of try_module_get()
ovl: rely on SB_I_NOUMASK
fs: fix umask on NFS with CONFIG_FS_POSIX_ACL=n
fs: store real path instead of fake path in backing file f_path
fs: create helper file_user_path() for user displayed mapped file path
fs: get mnt_writers count for an open backing file's real path
vfs: stop counting on gcc not messing with mnt_expiry_mark if not asked
vfs: predict the error in retry_estale as unlikely
backing file: free directly
vfs: fix readahead(2) on block devices
io_uring: use files_lookup_fd_locked()
file: convert to SLAB_TYPESAFE_BY_RCU
vfs: shave work on failed file open
fs: simplify misleading code to remove ambiguity regarding ihold()/iput()
watch_queue: Annotate struct watch_filter with __counted_by
fs/pipe: use spinlock in pipe_read() only if there is a watch_queue
fs/pipe: remove unnecessary spinlock from pipe_write()
...
With all users converted, remove the old create_empty_buffers() and rename
folio_create_empty_buffers() to create_empty_buffers().
Link: https://lkml.kernel.org/r/20231016201114.1928083-28-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Andreas Gruenbacher <agruenba@redhat.com>
Cc: Pankaj Raghav <p.raghav@samsung.com>
Cc: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Use the folio APIs, saving four hidden calls to compound_head().
Link: https://lkml.kernel.org/r/20231016201114.1928083-9-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
Cc: Pankaj Raghav <p.raghav@samsung.com>
Cc: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Remove several folio->page->folio conversions. Also use __GFP_NOFAIL
instead of calling yield() and the new get_nth_bh().
Link: https://lkml.kernel.org/r/20231016201114.1928083-8-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
Cc: Pankaj Raghav <p.raghav@samsung.com>
Cc: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Use the folio APIs, removing numerous hidden calls to compound_head().
Also remove the stale comment about the page being looked up if it's NULL.
Link: https://lkml.kernel.org/r/20231016201114.1928083-7-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Andreas Gruenbacher <agruenba@redhat.com>
Cc: Pankaj Raghav <p.raghav@samsung.com>
Cc: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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 recent discussions around some performance improvements in the file
handling area we discussed switching the file cache to rely on
SLAB_TYPESAFE_BY_RCU which allows us to get rid of call_rcu() based
freeing for files completely. This is a pretty sensitive change overall
but it might actually be worth doing.
The main downside is the subtlety. The other one is that we should
really wait for Jann's patch to land that enables KASAN to handle
SLAB_TYPESAFE_BY_RCU UAFs. Currently it doesn't but a patch for this
exists.
With SLAB_TYPESAFE_BY_RCU objects may be freed and reused multiple times
which requires a few changes. So it isn't sufficient anymore to just
acquire a reference to the file in question under rcu using
atomic_long_inc_not_zero() since the file might have already been
recycled and someone else might have bumped the reference.
In other words, callers might see reference count bumps from newer
users. For this reason it is necessary to verify that the pointer is the
same before and after the reference count increment. This pattern can be
seen in get_file_rcu() and __files_get_rcu().
In addition, it isn't possible to access or check fields in struct file
without first aqcuiring a reference on it. Not doing that was always
very dodgy and it was only usable for non-pointer data in struct file.
With SLAB_TYPESAFE_BY_RCU it is necessary that callers first acquire a
reference under rcu or they must hold the files_lock of the fdtable.
Failing to do either one of this is a bug.
Thanks to Jann for pointing out that we need to ensure memory ordering
between reallocations and pointer check by ensuring that all subsequent
loads have a dependency on the second load in get_file_rcu() and
providing a fixup that was folded into this patch.
Cc: Jann Horn <jannh@google.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
This makes it harder for accidental or malicious changes to
gfs2_xattr_handlers_max at runtime.
Cc: Bob Peterson <rpeterso@redhat.com>
Cc: Andreas Gruenbacher <agruenba@redhat.com>
Cc: cluster-devel@redhat.com
Signed-off-by: Wedson Almeida Filho <walmeida@microsoft.com>
Link: https://lore.kernel.org/r/20230930050033.41174-13-wedsonaf@gmail.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
Add a kthread_stop_put() helper that stops a thread and puts its task
struct. Use it to replace the various instances of kthread_stop()
followed by put_task_struct().
Remove the kthread_stop_put() macro in usbip that is similar but doesn't
return the result of kthread_stop().
[agruenba@redhat.com: fix kerneldoc comment]
Link: https://lkml.kernel.org/r/20230911111730.2565537-1-agruenba@redhat.com
[akpm@linux-foundation.org: document kthread_stop_put()'s argument]
Link: https://lkml.kernel.org/r/20230907234048.2499820-1-agruenba@redhat.com
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
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>
Before commit b77b4a4815 ("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>
Patch eef46ab713 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: eef46ab713 ("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: b77b4a4815 ("gfs2: Rework freeze / thaw logic")
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
- Fix a glock state (non-)transition bug when a dlm request times out
and is canceled, and we have locking requests that can now be granted
immediately.
- Various fixes and cleanups in how the logd and quotad daemons are
woken up and terminated.
- Fix several bugs in the quota data reference counting and shrinking.
Free quota data objects synchronously in put_super() instead of
letting call_rcu() run wild.
- Make sure not to deallocate quota data during a withdraw; rather, defer
quota data deallocation to put_super(). Withdraws can happen in
contexts in which callers on the stack are holding quota data references.
- Many minor quota fixes and cleanups by Bob.
- Update the the mailing list address for gfs2 and dlm. (It's the same
list for both and we are moving it to gfs2@lists.linux.dev.)
- Various other minor cleanups.
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Merge tag 'gfs2-v6.5-rc5-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2
Pull gfs2 updates from Andreas Gruenbacher:
- Fix a glock state (non-)transition bug when a dlm request times out
and is canceled, and we have locking requests that can now be granted
immediately
- Various fixes and cleanups in how the logd and quotad daemons are
woken up and terminated
- Fix several bugs in the quota data reference counting and shrinking.
Free quota data objects synchronously in put_super() instead of
letting call_rcu() run wild
- Make sure not to deallocate quota data during a withdraw; rather,
defer quota data deallocation to put_super(). Withdraws can happen in
contexts in which callers on the stack are holding quota data
references
- Many minor quota fixes and cleanups by Bob
- Update the the mailing list address for gfs2 and dlm. (It's the same
list for both and we are moving it to gfs2@lists.linux.dev)
- Various other minor cleanups
* tag 'gfs2-v6.5-rc5-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2: (51 commits)
MAINTAINERS: Update dlm mailing list
MAINTAINERS: Update gfs2 mailing list
gfs2: change qd_slot_count to qd_slot_ref
gfs2: check for no eligible quota changes
gfs2: Remove useless assignment
gfs2: simplify slot_get
gfs2: Simplify qd2offset
gfs2: introduce qd_bh_get_or_undo
gfs2: Remove quota allocation info from quota file
gfs2: use constant for array size
gfs2: Set qd_sync_gen in do_sync
gfs2: Remove useless err set
gfs2: Small gfs2_quota_lock cleanup
gfs2: move qdsb_put and reduce redundancy
gfs2: improvements to sysfs status
gfs2: Don't try to sync non-changes
gfs2: Simplify function need_sync
gfs2: remove unneeded pg_oflow variable
gfs2: remove unneeded variable done
gfs2: pass sdp to gfs2_write_buf_to_page
...
Variable qd_slot_count is a reference count, not a count of slots. This
patch renames it to qd_slot_ref to make that more clear.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Before this patch, function gfs2_quota_sync would always allocate a page
full of memory and increment its quota sync generation number. This
happened even when the system was completely idle or if no blocks were
allocated or quota changes made. This patch adds function qd_changed
to determine if any changes have been made that qualify for a
quota sync. If not, it avoids the memory allocation and bumping the
generation number, along with all the additional work it would do.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
This assignment is unnecessary because if error was not already 0, it
would have branched to an error label already.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Simplify function slot_get and get rid of the goto that jumps into the
middle of an else branch.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
This is a minor cleanup of function qd2offset.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
This patch is an attempt to force some consistency in quota sync
processing. Two functions (qd_fish and gfs2_quota_unlock) called
qd_check_sync, after which they both called bh_get, and if that failed,
they took the same steps to undo the actions of qd_check_sync.
This patch introduces a new function, qd_bh_get_or_undo, which performs
the same steps, reducing code redundancy.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Function do_sync called gfs2_qa_get and put for quota allocation data.
But the inode in question is the system master quota file, which is
never subject to quotas. Therefore, a qa structure should be unnecessary
and if anything accesses it, it's probably a bug.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Function gfs2_quota_unlock declared an array of 4 qd elements. We have a
constant for that, we should be using it.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Func do_sync was called in two places: gfs2_quota_unlock and
gfs2_quota_sync. In gfs2_quota_sync it updated qd_sync_gen to the latest
superblock sync gen, if do_sync was successful. In gfs2_quota_unlock it
didn't update the value. That can only lead to extra work, for example,
if the value is synced by gfs2_quota_unlock but still has the old value.
This patch moves the setting of qd_sync_gen inside do_sync so we are
guaranteed consistency.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Function gfs2_adjust_quota set variable err, then set it again to a
different value. This patch removes the redundant set.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
No need to set error = 0 since it's set further down.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
This patch looks more invasive than it is. It simply moves function
qdsb_put before qd_unlock, then changes qd_unlock to call it rather than
open coding it. Again, this reduces redundancy.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
This patch adds some new fields to the gfs2 status file in sysfs to aid
in debugging.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Function need_sync is supposed to determine if a qd element needs to be
synced. If the "change" (qd_change) is zero, it does not need to be
synced because there's literally no change in the value. Before this
patch need_sync returned false if value < 0. That should be <= 0.
This patch changes the check to <=.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
This patch simplifies function need_sync by eliminating a variable in
favor of just returning the appropriate value as soon as we know it.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Function gfs2_write_disk_quota checks if its write overflows onto
another page, and if so, does a second write. Before this patch it kept
two variables for this, but only one is needed. This patch simplifies
it by eliminating pg_oflow.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Function gfs2_write_buf_to_page uses variable done to exit its loop, but
it's unnecessary if we just code an infinite loop and exit when we need.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
This patch passes the superblock pointer to gfs2_write_buf_to_page so it
becomes more apparent it's dealing with the system quota file.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Like the previous patch, we now pass the superblock pointer to function
gfs2_write_disk_quota. This makes the code more understandable, since it
only operates on the quota inode.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Before this change function gfs2_adjust_quota's first parameter was an
gfs2_inode pointer. But it always pointed to the quota inode. Here we
switch that to pass the superblock pointer, sdp, so it is easier to read
the code and understand that it's only dealing with the quota inode.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Since patch 845802b112 function gfs2_write_buf_to_page checks if the
target inode is jdata or ordered. This function only operates on the
system quota file, which is always jdata, so the check for jdata is
useless. This patch removes it.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
This patch adds a new mount option quota=quiet which is the same as
quota=on but it suppresses gfs2 quota error messages.
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Add the device name to the names of the gfs2_logd and gfs2_quotad kernel
threads to allow for easier identification.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Rename the "gfs_recovery" workqueue to "gfs2_recovery", and
gfs_recovery_wq to gfs2_recovery_wq.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Function gfs2_withdraw() tries to synchronize concurrent callers by
atomically setting the SDF_WITHDRAWN flag in the first caller, setting
the SDF_WITHDRAW_IN_PROG flag to indicate that a withdraw is in
progress, performing the actual withdraw, and clearing the
SDF_WITHDRAW_IN_PROG flag when done. All other callers wait for the
SDF_WITHDRAW_IN_PROG flag to be cleared before returning.
This leaves a small window in which callers can find the SDF_WITHDRAWN
flag set before the SDF_WITHDRAW_IN_PROG flag has been set, causing them
to return prematurely, before the withdraw has been completed.
Fix that by setting the SDF_WITHDRAWN and SDF_WITHDRAW_IN_PROG flags
atomically.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Immediately stop the logd and quotad kernel threads when a filesystem
withdraw is detected: those threads aren't doing anything useful after a
withdraw. (Depends on the extra logd and quotad task struct references
held since commit 7a109f383fa3 ("gfs2: Fix asynchronous thread
destruction").)
In addition, check for kthread_should_stop() in the wait condition in
gfs2_quotad() to stop immediately when kthread_stop() is called.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
The kernel threads are currently stopped and destroyed synchronously by
gfs2_make_fs_ro() and gfs2_put_super(), and asynchronously by
signal_our_withdraw(), with no synchronization, so the synchronous and
asynchronous contexts can race with each other.
First, when creating the kernel threads, take an extra task struct
reference so that the task struct won't go away immediately when they
terminate. This allows those kthreads to terminate immediately when
they're done rather than hanging around as zombies until they are reaped
by kthread_stop(). When kthread_stop() is called on a terminated
kthread, it will return immediately.
Second, in signal_our_withdraw(), once the SDF_JOURNAL_LIVE flag has
been cleared, wake up the logd and quotad wait queues instead of
stopping the logd and quotad kthreads. The kthreads are then expected
to terminate automatically within short time, but if they cannot, they
will not block the withdraw.
For example, if a user process and one of the kthread decide to withdraw
at the same time, only one of them will perform the actual withdraw and
the other will wait for it to be done. If the kthread ends up being the
one to wait, the withdrawing user process won't be able to stop it.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
[ 81.372851][ T5532] CPU: 1 PID: 5532 Comm: syz-executor.0 Not tainted 6.2.0-rc1-syzkaller-dirty #0
[ 81.382080][ T5532] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023
[ 81.392343][ T5532] Call Trace:
[ 81.395654][ T5532] <TASK>
[ 81.398603][ T5532] dump_stack_lvl+0x1b1/0x290
[ 81.418421][ T5532] gfs2_assert_warn_i+0x19a/0x2e0
[ 81.423480][ T5532] gfs2_quota_cleanup+0x4c6/0x6b0
[ 81.428611][ T5532] gfs2_make_fs_ro+0x517/0x610
[ 81.457802][ T5532] gfs2_withdraw+0x609/0x1540
[ 81.481452][ T5532] gfs2_inode_refresh+0xb2d/0xf60
[ 81.506658][ T5532] gfs2_instantiate+0x15e/0x220
[ 81.511504][ T5532] gfs2_glock_wait+0x1d9/0x2a0
[ 81.516352][ T5532] do_sync+0x485/0xc80
[ 81.554943][ T5532] gfs2_quota_sync+0x3da/0x8b0
[ 81.559738][ T5532] gfs2_sync_fs+0x49/0xb0
[ 81.564063][ T5532] sync_filesystem+0xe8/0x220
[ 81.568740][ T5532] generic_shutdown_super+0x6b/0x310
[ 81.574112][ T5532] kill_block_super+0x79/0xd0
[ 81.578779][ T5532] deactivate_locked_super+0xa7/0xf0
[ 81.584064][ T5532] cleanup_mnt+0x494/0x520
[ 81.593753][ T5532] task_work_run+0x243/0x300
[ 81.608837][ T5532] exit_to_user_mode_loop+0x124/0x150
[ 81.614232][ T5532] exit_to_user_mode_prepare+0xb2/0x140
[ 81.619820][ T5532] syscall_exit_to_user_mode+0x26/0x60
[ 81.625287][ T5532] do_syscall_64+0x49/0xb0
[ 81.629710][ T5532] entry_SYSCALL_64_after_hwframe+0x63/0xcd
In this backtrace, gfs2_quota_sync() takes quota data references and
then calls do_sync(). Function do_sync() encounters filesystem
corruption and withdraws the filesystem, which (among other things) calls
gfs2_quota_cleanup(). Function gfs2_quota_cleanup() wrongly assumes
that nobody is holding any quota data references anymore, and destroys
all quota data objects. When gfs2_quota_sync() then resumes and
dereferences the quota data objects it is holding, those objects are no
longer there.
Function gfs2_quota_cleanup() deals with resource deallocation and can
easily be delayed until gfs2_put_super() in the case of a filesystem
withdraw. In fact, most of the other work gfs2_make_fs_ro() does is
unnecessary during a withdraw as well, so change signal_our_withdraw()
to skip gfs2_make_fs_ro() and perform the necessary steps directly
instead.
Thanks to Edward Adam Davis <eadavis@sina.com> for the initial patches.
Link: https://lore.kernel.org/all/0000000000002b5e2405f14e860f@google.com
Reported-by: syzbot+3f6a670108ce43356017@syzkaller.appspotmail.com
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
In gfs2_quota_cleanup(), wait for the quota data objects to be freed
before returning. Otherwise, there is no guarantee that the quota data
objects will be gone when their kmem cache is destroyed.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Fix the refcount of quota data objects created directly by
gfs2_quota_init(): those are placed into the in-memory quota "database"
for eventual syncing to the main quota file, but they are not actively
held and should thus have an initial refcount of 0.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Once a filesystem is withdrawn, don't complain about quota changes
that can't be synced to the main quota file anymore.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Rename gfs2_qd_dispose() to gfs2_qd_dispose_list(). Move some code
duplicated in gfs2_qd_dispose_list() and gfs2_quota_cleanup() into a
new gfs2_qd_dispose() function.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Change gfs2_quota_cleanup() to move the quota data objects to dispose of
on a dispose list and call gfs2_qd_dispose() on that list, like
gfs2_qd_shrink_scan() does, instead of disposing of the quota data
objects directly.
This may look a bit pointless by itself, but it will make more sense in
combination with a fix that follows.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
