capable() calls refer to enabled LSMs whether to permit or deny the
request. This is relevant in connection with SELinux, where a
capability check results in a policy decision and by default a denial
message on insufficient permission is issued.
It can lead to three undesired cases:
1. A denial message is generated, even in case the operation was an
unprivileged one and thus the syscall succeeded, creating noise.
2. To avoid the noise from 1. the policy writer adds a rule to ignore
those denial messages, hiding future syscalls, where the task
performs an actual privileged operation, leading to hidden limited
functionality of that task.
3. To avoid the noise from 1. the policy writer adds a rule to permit
the task the requested capability, while it does not need it,
violating the principle of least privilege.
Signed-off-by: Christian Göttsche <cgzones@googlemail.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
- Fix the code that cleans up left-over unlinked files. Various fixes
and minor improvements in deleting files cached or held open remotely.
- Simplify the use of dlm's DLM_LKF_QUECVT flag.
- A few other minor cleanups.
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Merge tag 'gfs2-for-6.13' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2
Pull gfs2 updates from Andreas Gruenbacher:
- Fix the code that cleans up left-over unlinked files.
Various fixes and minor improvements in deleting files cached or held
open remotely.
- Simplify the use of dlm's DLM_LKF_QUECVT flag.
- A few other minor cleanups.
* tag 'gfs2-for-6.13' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2: (21 commits)
gfs2: Prevent inode creation race
gfs2: Only defer deletes when we have an iopen glock
gfs2: Simplify DLM_LKF_QUECVT use
gfs2: gfs2_evict_inode clarification
gfs2: Make gfs2_inode_refresh static
gfs2: Use get_random_u32 in gfs2_orlov_skip
gfs2: Randomize GLF_VERIFY_DELETE work delay
gfs2: Use mod_delayed_work in gfs2_queue_try_to_evict
gfs2: Update to the evict / remote delete documentation
gfs2: Call gfs2_queue_verify_delete from gfs2_evict_inode
gfs2: Clean up delete work processing
gfs2: Minor delete_work_func cleanup
gfs2: Return enum evict_behavior from gfs2_upgrade_iopen_glock
gfs2: Rename dinode_demise to evict_behavior
gfs2: Rename GIF_{DEFERRED -> DEFER}_DELETE
gfs2: Faster gfs2_upgrade_iopen_glock wakeups
KMSAN: uninit-value in inode_go_dump (5)
gfs2: Fix unlinked inode cleanup
gfs2: Allow immediate GLF_VERIFY_DELETE work
gfs2: Initialize gl_no_formal_ino earlier
...
Sergey Senozhatsky improves zram's post-processing selection algorithm.
This leads to improved memory savings.
- Wei Yang has gone to town on the mapletree code, contributing several
series which clean up the implementation:
- "refine mas_mab_cp()"
- "Reduce the space to be cleared for maple_big_node"
- "maple_tree: simplify mas_push_node()"
- "Following cleanup after introduce mas_wr_store_type()"
- "refine storing null"
- The series "selftests/mm: hugetlb_fault_after_madv improvements" from
David Hildenbrand fixes this selftest for s390.
- The series "introduce pte_offset_map_{ro|rw}_nolock()" from Qi Zheng
implements some rationaizations and cleanups in the page mapping code.
- The series "mm: optimize shadow entries removal" from Shakeel Butt
optimizes the file truncation code by speeding up the handling of shadow
entries.
- The series "Remove PageKsm()" from Matthew Wilcox completes the
migration of this flag over to being a folio-based flag.
- The series "Unify hugetlb into arch_get_unmapped_area functions" from
Oscar Salvador implements a bunch of consolidations and cleanups in the
hugetlb code.
- The series "Do not shatter hugezeropage on wp-fault" from Dev Jain
takes away the wp-fault time practice of turning a huge zero page into
small pages. Instead we replace the whole thing with a THP. More
consistent cleaner and potentiall saves a large number of pagefaults.
- The series "percpu: Add a test case and fix for clang" from Andy
Shevchenko enhances and fixes the kernel's built in percpu test code.
- The series "mm/mremap: Remove extra vma tree walk" from Liam Howlett
optimizes mremap() by avoiding doing things which we didn't need to do.
- The series "Improve the tmpfs large folio read performance" from
Baolin Wang teaches tmpfs to copy data into userspace at the folio size
rather than as individual pages. A 20% speedup was observed.
- The series "mm/damon/vaddr: Fix issue in
damon_va_evenly_split_region()" fro Zheng Yejian fixes DAMON splitting.
- The series "memcg-v1: fully deprecate charge moving" from Shakeel Butt
removes the long-deprecated memcgv2 charge moving feature.
- The series "fix error handling in mmap_region() and refactor" from
Lorenzo Stoakes cleanup up some of the mmap() error handling and
addresses some potential performance issues.
- The series "x86/module: use large ROX pages for text allocations" from
Mike Rapoport teaches x86 to use large pages for read-only-execute
module text.
- The series "page allocation tag compression" from Suren Baghdasaryan
is followon maintenance work for the new page allocation profiling
feature.
- The series "page->index removals in mm" from Matthew Wilcox remove
most references to page->index in mm/. A slow march towards shrinking
struct page.
- The series "damon/{self,kunit}tests: minor fixups for DAMON debugfs
interface tests" from Andrew Paniakin performs maintenance work for
DAMON's self testing code.
- The series "mm: zswap swap-out of large folios" from Kanchana Sridhar
improves zswap's batching of compression and decompression. It is a
step along the way towards using Intel IAA hardware acceleration for
this zswap operation.
- The series "kasan: migrate the last module test to kunit" from
Sabyrzhan Tasbolatov completes the migration of the KASAN built-in tests
over to the KUnit framework.
- The series "implement lightweight guard pages" from Lorenzo Stoakes
permits userapace to place fault-generating guard pages within a single
VMA, rather than requiring that multiple VMAs be created for this.
Improved efficiencies for userspace memory allocators are expected.
- The series "memcg: tracepoint for flushing stats" from JP Kobryn uses
tracepoints to provide increased visibility into memcg stats flushing
activity.
- The series "zram: IDLE flag handling fixes" from Sergey Senozhatsky
fixes a zram buglet which potentially affected performance.
- The series "mm: add more kernel parameters to control mTHP" from
Maíra Canal enhances our ability to control/configuremultisize THP from
the kernel boot command line.
- The series "kasan: few improvements on kunit tests" from Sabyrzhan
Tasbolatov has a couple of fixups for the KASAN KUnit tests.
- The series "mm/list_lru: Split list_lru lock into per-cgroup scope"
from Kairui Song optimizes list_lru memory utilization when lockdep is
enabled.
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Merge tag 'mm-stable-2024-11-18-19-27' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
Pull MM updates from Andrew Morton:
- The series "zram: optimal post-processing target selection" from
Sergey Senozhatsky improves zram's post-processing selection
algorithm. This leads to improved memory savings.
- Wei Yang has gone to town on the mapletree code, contributing several
series which clean up the implementation:
- "refine mas_mab_cp()"
- "Reduce the space to be cleared for maple_big_node"
- "maple_tree: simplify mas_push_node()"
- "Following cleanup after introduce mas_wr_store_type()"
- "refine storing null"
- The series "selftests/mm: hugetlb_fault_after_madv improvements" from
David Hildenbrand fixes this selftest for s390.
- The series "introduce pte_offset_map_{ro|rw}_nolock()" from Qi Zheng
implements some rationaizations and cleanups in the page mapping
code.
- The series "mm: optimize shadow entries removal" from Shakeel Butt
optimizes the file truncation code by speeding up the handling of
shadow entries.
- The series "Remove PageKsm()" from Matthew Wilcox completes the
migration of this flag over to being a folio-based flag.
- The series "Unify hugetlb into arch_get_unmapped_area functions" from
Oscar Salvador implements a bunch of consolidations and cleanups in
the hugetlb code.
- The series "Do not shatter hugezeropage on wp-fault" from Dev Jain
takes away the wp-fault time practice of turning a huge zero page
into small pages. Instead we replace the whole thing with a THP. More
consistent cleaner and potentiall saves a large number of pagefaults.
- The series "percpu: Add a test case and fix for clang" from Andy
Shevchenko enhances and fixes the kernel's built in percpu test code.
- The series "mm/mremap: Remove extra vma tree walk" from Liam Howlett
optimizes mremap() by avoiding doing things which we didn't need to
do.
- The series "Improve the tmpfs large folio read performance" from
Baolin Wang teaches tmpfs to copy data into userspace at the folio
size rather than as individual pages. A 20% speedup was observed.
- The series "mm/damon/vaddr: Fix issue in
damon_va_evenly_split_region()" fro Zheng Yejian fixes DAMON
splitting.
- The series "memcg-v1: fully deprecate charge moving" from Shakeel
Butt removes the long-deprecated memcgv2 charge moving feature.
- The series "fix error handling in mmap_region() and refactor" from
Lorenzo Stoakes cleanup up some of the mmap() error handling and
addresses some potential performance issues.
- The series "x86/module: use large ROX pages for text allocations"
from Mike Rapoport teaches x86 to use large pages for
read-only-execute module text.
- The series "page allocation tag compression" from Suren Baghdasaryan
is followon maintenance work for the new page allocation profiling
feature.
- The series "page->index removals in mm" from Matthew Wilcox remove
most references to page->index in mm/. A slow march towards shrinking
struct page.
- The series "damon/{self,kunit}tests: minor fixups for DAMON debugfs
interface tests" from Andrew Paniakin performs maintenance work for
DAMON's self testing code.
- The series "mm: zswap swap-out of large folios" from Kanchana Sridhar
improves zswap's batching of compression and decompression. It is a
step along the way towards using Intel IAA hardware acceleration for
this zswap operation.
- The series "kasan: migrate the last module test to kunit" from
Sabyrzhan Tasbolatov completes the migration of the KASAN built-in
tests over to the KUnit framework.
- The series "implement lightweight guard pages" from Lorenzo Stoakes
permits userapace to place fault-generating guard pages within a
single VMA, rather than requiring that multiple VMAs be created for
this. Improved efficiencies for userspace memory allocators are
expected.
- The series "memcg: tracepoint for flushing stats" from JP Kobryn uses
tracepoints to provide increased visibility into memcg stats flushing
activity.
- The series "zram: IDLE flag handling fixes" from Sergey Senozhatsky
fixes a zram buglet which potentially affected performance.
- The series "mm: add more kernel parameters to control mTHP" from
Maíra Canal enhances our ability to control/configuremultisize THP
from the kernel boot command line.
- The series "kasan: few improvements on kunit tests" from Sabyrzhan
Tasbolatov has a couple of fixups for the KASAN KUnit tests.
- The series "mm/list_lru: Split list_lru lock into per-cgroup scope"
from Kairui Song optimizes list_lru memory utilization when lockdep
is enabled.
* tag 'mm-stable-2024-11-18-19-27' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (215 commits)
cma: enforce non-zero pageblock_order during cma_init_reserved_mem()
mm/kfence: add a new kunit test test_use_after_free_read_nofault()
zram: fix NULL pointer in comp_algorithm_show()
memcg/hugetlb: add hugeTLB counters to memcg
vmstat: call fold_vm_zone_numa_events() before show per zone NUMA event
mm: mmap_lock: check trace_mmap_lock_$type_enabled() instead of regcount
zram: ZRAM_DEF_COMP should depend on ZRAM
MAINTAINERS/MEMORY MANAGEMENT: add document files for mm
Docs/mm/damon: recommend academic papers to read and/or cite
mm: define general function pXd_init()
kmemleak: iommu/iova: fix transient kmemleak false positive
mm/list_lru: simplify the list_lru walk callback function
mm/list_lru: split the lock to per-cgroup scope
mm/list_lru: simplify reparenting and initial allocation
mm/list_lru: code clean up for reparenting
mm/list_lru: don't export list_lru_add
mm/list_lru: don't pass unnecessary key parameters
kasan: add kunit tests for kmalloc_track_caller, kmalloc_node_track_caller
kasan: change kasan_atomics kunit test as KUNIT_CASE_SLOW
kasan: use EXPORT_SYMBOL_IF_KUNIT to export symbols
...
When a request to evict an inode comes in over the network, we are
trying to grab an inode reference via the iopen glock's gl_object
pointer. There is a very small probability that by the time such a
request comes in, inode creation hasn't completed and the I_NEW flag is
still set. To deal with that, wait for the inode and then check if
inode creation was successful.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
The mechanism to defer deleting unlinked inodes is tied to
delete_work_func(), which is tied to iopen glocks. When we don't have
an iopen glock, we must carry out deletes immediately instead.
Fixes a NULL pointer dereference in gfs2_evict_inode().
Fixes: 8c21c2c71e ("gfs2: Call gfs2_queue_verify_delete from gfs2_evict_inode")
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
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Merge tag 'vfs-6.13.file' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs
Pull vfs file updates from Christian Brauner:
"This contains changes the changes for files for this cycle:
- Introduce a new reference counting mechanism for files.
As atomic_inc_not_zero() is implemented with a try_cmpxchg() loop
it has O(N^2) behaviour under contention with N concurrent
operations and it is in a hot path in __fget_files_rcu().
The rcuref infrastructures remedies this problem by using an
unconditional increment relying on safe- and dead zones to make
this work and requiring rcu protection for the data structure in
question. This not just scales better it also introduces overflow
protection.
However, in contrast to generic rcuref, files require a memory
barrier and thus cannot rely on *_relaxed() atomic operations and
also require to be built on atomic_long_t as having massive amounts
of reference isn't unheard of even if it is just an attack.
This adds a file specific variant instead of making this a generic
library.
This has been tested by various people and it gives consistent
improvement up to 3-5% on workloads with loads of threads.
- Add a fastpath for find_next_zero_bit(). Skip 2-levels searching
via find_next_zero_bit() when there is a free slot in the word that
contains the next fd. This improves pts/blogbench-1.1.0 read by 8%
and write by 4% on Intel ICX 160.
- Conditionally clear full_fds_bits since it's very likely that a bit
in full_fds_bits has been cleared during __clear_open_fds(). This
improves pts/blogbench-1.1.0 read up to 13%, and write up to 5% on
Intel ICX 160.
- Get rid of all lookup_*_fdget_rcu() variants. They were used to
lookup files without taking a reference count. That became invalid
once files were switched to SLAB_TYPESAFE_BY_RCU and now we're
always taking a reference count. Switch to an already existing
helper and remove the legacy variants.
- Remove pointless includes of <linux/fdtable.h>.
- Avoid cmpxchg() in close_files() as nobody else has a reference to
the files_struct at that point.
- Move close_range() into fs/file.c and fold __close_range() into it.
- Cleanup calling conventions of alloc_fdtable() and expand_files().
- Merge __{set,clear}_close_on_exec() into one.
- Make __set_open_fd() set cloexec as well instead of doing it in two
separate steps"
* tag 'vfs-6.13.file' of git://git.kernel.org/pub/scm/linux/kernel/git/vfs/vfs:
selftests: add file SLAB_TYPESAFE_BY_RCU recycling stressor
fs: port files to file_ref
fs: add file_ref
expand_files(): simplify calling conventions
make __set_open_fd() set cloexec state as well
fs: protect backing files with rcu
file.c: merge __{set,clear}_close_on_exec()
alloc_fdtable(): change calling conventions.
fs/file.c: add fast path in find_next_fd()
fs/file.c: conditionally clear full_fds
fs/file.c: remove sanity_check and add likely/unlikely in alloc_fd()
move close_range(2) into fs/file.c, fold __close_range() into it
close_files(): don't bother with xchg()
remove pointless includes of <linux/fdtable.h>
get rid of ...lookup...fdget_rcu() family
Now isolation no longer takes the list_lru global node lock, only use the
per-cgroup lock instead. And this lock is inside the list_lru_one being
walked, no longer needed to pass the lock explicitly.
Link: https://lkml.kernel.org/r/20241104175257.60853-7-ryncsn@gmail.com
Signed-off-by: Kairui Song <kasong@tencent.com>
Cc: Chengming Zhou <zhouchengming@bytedance.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Muchun Song <muchun.song@linux.dev>
Cc: Qi Zheng <zhengqi.arch@bytedance.com>
Cc: Roman Gushchin <roman.gushchin@linux.dev>
Cc: Shakeel Butt <shakeel.butt@linux.dev>
Cc: Waiman Long <longman@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
The DLM_LKF_QUECVT flag needs to be set for "upward" lock conversions to
ensure fairness, but setting it for "downward" lock conversions will
lead to a failure. The flag is currently set based on the GLF_BLOCKING
flag and it's not immediately obvious why this is correct. Simplify
things by figuring out if a lock conversion is "upward" by looking at
the before and after locking modes instead of relying on the
GLF_BLOCKING flag.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
When function evict_should_delete() returns SHOULD_DEFER_EVICTION, gh is
never initialized, but that isn't obvious; if it did initialize gh and
then return SHOULD_DEFER_EVICTION, gfs2_evict_inode() would fail to
release it. To clarify the code, change gfs2_evict_inode() to always
check if gh needs to be released, no matter what evict_should_delete()
returns.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Use get_random_u32() instead of get_random_bytes() to remove the last
remaining call to get_random_bytes().
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Randomize the delay of GLF_VERIFY_DELETE work. This avoids thundering
herd problems when multiple nodes schedule that kind of work in response
to an inode being unlinked remotely.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
In the unlikely case that we're trying to queue GLF_TRY_TO_EVICT work
for an inode that already has GLF_VERIFY_DELETE work queued, we want to
make sure that the GLF_TRY_TO_EVICT work gets scheduled immediately
instead of waiting for the delayed work timer to expire.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Try to be a bit more clear and remove some duplications. We cannot
actually get rid of the verification step eventually, so remove the
comment saying so.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Function delete_work_func() was previously assuming that the
GLF_TRY_TO_EVICT and GLF_VERIFY_DELETE flags won't both be set at the
same time, but there probably are races in which that can happen, so
handle that case correctly.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
In case an iopen glock cannot be upgraded, function
gfs2_upgrade_iopen_glock() needs to communicate to gfs2_evict_inode()
whether deleting the inode should be deferred or skipped altogether.
Change the function to return the appropriate enum evict_behavior value
to indicate that.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Rename enum dinode_demise to evict_behavior and its items
SHOULD_DELETE_DINODE to EVICT_SHOULD_DELETE,
SHOULD_NOT_DELETE_DINODE to EVICT_SHOULD_SKIP_DELETE, and
SHOULD_DEFER_EVICTION to EVICT_SHOULD_DEFER_DELETE.
In gfs2_evict_inode(), add a separate variable of type enum
evict_behavior instead of implicitly casting to int.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
The GIF_DEFERRED_DELETE flag indicates an action that gfs2_evict_inode()
should take, so rename the flag to GIF_DEFER_DELETE to clarify.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Move function needs_demote() to glock.h and rename it to
glock_needs_demote(). In handle_callback(), wake up the glock when
setting the GLF_PENDING_DEMOTE flag as well. (Setting the GLF_DEMOTE
flag already triggered a wake-up.)
With that, check for glock_needs_demote() in gfs2_upgrade_iopen_glock()
to wake up when either of those flags is set for the inode glock: the
faster we can react to contention, the better.
The GLF_PENDING_DEMOTE flag is only used for inode glocks (see
gfs2_glock_cb()) so it's okay to only check for the GLF_DEMOTE flag in
gfs2_drop_inode(). Still, using glock_needs_demote() there as well
makes the code a little easier to read.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
When mounting of a corrupted disk image fails, the error message printed
can reference uninitialized inode fields. To prevent that from happening,
always initialize those fields.
Reported-by: syzbot+aa0730b0a42646eb1359@syzkaller.appspotmail.com
Signed-off-by: Qianqiang Liu <qianqiang.liu@163.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Once upon a time, predecessors of those used to do file lookup
without bumping a refcount, provided that caller held rcu_read_lock()
across the lookup and whatever it wanted to read from the struct
file found. When struct file allocation switched to SLAB_TYPESAFE_BY_RCU,
that stopped being feasible and these primitives started to bump the
file refcount for lookup result, requiring the caller to call fput()
afterwards.
But that turned them pointless - e.g.
rcu_read_lock();
file = lookup_fdget_rcu(fd);
rcu_read_unlock();
is equivalent to
file = fget_raw(fd);
and all callers of lookup_fdget_rcu() are of that form. Similarly,
task_lookup_fdget_rcu() calls can be replaced with calling fget_task().
task_lookup_next_fdget_rcu() doesn't have direct counterparts, but
its callers would be happier if we replaced it with an analogue that
deals with RCU internally.
Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Benjamin Coddington <bcodding@redhat.com> says:
Last year both GFS2 and OCFS2 had some work done to make their locking more
robust when exported over NFS. Unfortunately, part of that work caused both
NLM (for NFS v3 exports) and kNFSD (for NFSv4.1+ exports) to no longer send
lock notifications to clients.
This in itself is not a huge problem because most NFS clients will still
poll the server in order to acquire a conflicted lock, but now that I've
noticed it I can't help but try to fix it because there are big advantages
for setups that might depend on timely lock notifications, and we've
supported that as a feature for a long time.
Its important for NLM and kNFSD that they do not block their kernel threads
inside filesystem's file_lock implementations because that can produce
deadlocks. We used to make sure of this by only trusting that
posix_lock_file() can correctly handle blocking lock calls asynchronously,
so the lock managers would only setup their file_lock requests for async
callbacks if the filesystem did not define its own lock() file operation.
However, when GFS2 and OCFS2 grew the capability to correctly
handle blocking lock requests asynchronously, they started signalling this
behavior with EXPORT_OP_ASYNC_LOCK, and the check for also trusting
posix_lock_file() was inadvertently dropped, so now most filesystems no
longer produce lock notifications when exported over NFS.
I tried to fix this by simply including the old check for lock(), but the
resulting include mess and layering violations was more than I could accept.
There's a much cleaner way presented here using an fop_flag, which while
potentially flag-greedy, greatly simplifies the problem and grooms the
way for future uses by both filesystems and lock managers alike.
* patches from https://lore.kernel.org/r/cover.1726083391.git.bcodding@redhat.com:
exportfs: Remove EXPORT_OP_ASYNC_LOCK
NLM/NFSD: Fix lock notifications for async-capable filesystems
gfs2/ocfs2: set FOP_ASYNC_LOCK
fs: Introduce FOP_ASYNC_LOCK
NFS: trace: show TIMEDOUT instead of 0x6e
nfsd: use system_unbound_wq for nfsd_file_gc_worker()
nfsd: count nfsd_file allocations
nfsd: fix refcount leak when file is unhashed after being found
nfsd: remove unneeded EEXIST error check in nfsd_do_file_acquire
nfsd: add list_head nf_gc to struct nfsd_file
Link: https://lore.kernel.org/r/cover.1726083391.git.bcodding@redhat.com
Signed-off-by: Christian Brauner <brauner@kernel.org>
Now that GFS2 and OCFS2 are signalling async ->lock() support with
FOP_ASYNC_LOCK and checks for support are converted, we can remove
EXPORT_OP_ASYNC_LOCK.
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Link: https://lore.kernel.org/r/0a114db814fec3086f937ae3d44a086f13b8de26.1726083391.git.bcodding@redhat.com
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Before commit f0e56edc2e ("gfs2: Split the two kinds of glock "delete"
work"), function delete_work_func() was used to trigger the eviction of
in-memory inodes from remote as well as deleting unlinked inodes at a
later point. These two kinds of work were then split into two kinds of
work, and the two places in the code were deferred deletion of inodes is
required accidentally ended up queuing the wrong kind of work. This
caused unlinked inodes to be left behind, which could in the worst case
fill up filesystems and require a filesystem check to recover.
Fix that by queuing the right kind of work in try_rgrp_unlink() and
gfs2_drop_inode().
Fixes: f0e56edc2e ("gfs2: Split the two kinds of glock "delete" work")
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Add an argument to gfs2_queue_verify_delete() that allows it to queue
GLF_VERIFY_DELETE work for immediate execution. This is used in the
next patch.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Set gl_no_formal_ino of the iopen glock to the generation of the
associated inode (ip->i_no_formal_ino) as soon as that value is known.
This saves us from setting it later, possibly repeatedly, when queuing
GLF_VERIFY_DELETE work.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Rename the GLF_VERIFY_EVICT flag to GLF_VERIFY_DELETE: that flag
indicates that we want to delete an inode / verify that it has been
deleted.
To match, rename gfs2_queue_verify_evict() to
gfs2_queue_verify_delete().
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
- Eliminate the writepage address space operation (by Matthew Wilcox).
- A syzkaller fix (by Julian Sun) and a minor cleanup (by Andreas
Gruenbacher).
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Merge tag 'gfs2-v6.10-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2
Pull gfs2 update from Andreas Gruenbacher:
- Convert the writepage address space operation to writepages (Matthew
Wilcox)
- A syzkaller fix (by Julian Sun) and a minor cleanup (Andreas
Gruenbacher)
* tag 'gfs2-v6.10-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/gfs2/linux-gfs2:
gfs2: Remove gfs2_aspace_writepage()
gfs2: Remove gfs2_jdata_writepage()
gfs2: Remove __gfs2_writepage()
gfs2: Add gfs2_aspace_writepages()
gfs2: fix double destroy_workqueue error
gfs2: Minor gfs2_glock_cb cleanup
In order to switch fuse over to using iomap for buffered writes we need
to be able to have the struct file for the original write, in case we
have to read in the page to make it uptodate. Handle this by using the
existing private field in the iomap_iter, and add the argument to
iomap_file_buffered_write. This will allow us to pass the file in
through the iomap buffered write path, and is flexible for any other
file systems needs.
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Link: https://lore.kernel.org/r/7f55c7c32275004ba00cddf862d970e6e633f750.1724755651.git.josef@toxicpanda.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christian Brauner <brauner@kernel.org>
There are no remaining callers of gfs2_aspace_writepage() other than
vmscan, which is known to do more harm than good.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
There are no remaining callers of gfs2_jdata_writepage() other than
vmscan, which is known to do more harm than good.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Call aops->writepages() instead of using write_cache_pages() to call
aops->writepage. Change the handling of -ENODATA to not set the
persistent error on the block device.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
This saves one indirect function call per folio and gets us closer to
removing aops->writepage.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
When gfs2_fill_super() fails, destroy_workqueue() is called within
gfs2_gl_hash_clear(), and the subsequent code path calls
destroy_workqueue() on the same work queue again.
This issue can be fixed by setting the work queue pointer to NULL after
the first destroy_workqueue() call and checking for a NULL pointer
before attempting to destroy the work queue again.
Reported-by: syzbot+d34c2a269ed512c531b0@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=d34c2a269ed512c531b0
Fixes: 30e388d573 ("gfs2: Switch to a per-filesystem glock workqueue")
Cc: stable@vger.kernel.org
Signed-off-by: Julian Sun <sunjunchao2870@gmail.com>
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
In gfs2_glock_cb(), we only need to calculate the glock hold time for
inode glocks; the value is unused otherwise.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
The logic for determining when to demote a glock in glock_work_func(),
introduced in commit 7cf8dcd3b6 ("GFS2: Automatically adjust glock min
hold time"), doesn't make sense: inode glocks have a minimum hold time
that delays demotion, while all other glocks are expected to be demoted
immediately. Instead of demoting non-inode glocks immediately,
glock_work_func() schedules glock work for them to be demoted, however.
Get rid of that unnecessary indirection.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Since the previous commit, function gfs2_quota_sync() will not cause the
sync generation to creep forward by one every time the function is
called; this helps keep things a but more tidy. We also don't care that
this function allocates a page of memory every time it is called, so no
good reason for keeping qd_changed() anymore, which just duplicates
qd_grab_sync().
This reverts commit 06aa6fd31a.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
The quota sync generation is only ever updated under sd_quota_sync_mutex
by gfs2_quota_sync(), but its current value is fetched ouside of that
mutex, so use WRITE_ONCE() and READ_ONCE() when accessing it without
holding that mutex.
Pass the current sync generation to do_sync() from its callers to ensure
that we're not recording the wrong generation when the syncing is
done. Also, make sure that qd->qd_sync_gen only ever moves forward.
In gfs2_quota_sync(), only write the new sync generation when we know
that there are changes. This eliminates the need for function
sd_changed(), which we will remove in the next commit.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
With the locking the previous patch has introduced for each struct
gfs2_quota_data object, sd_quota_mutex has become largely irrelevant.
By waiting on the buffer head instead of waiting on the mutex in
get_bh(), it becomes completely irrelevant and can be removed.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
The quota code is missing some locking between local quota changes and
syncing those quota changes to the global quota file (gfs2_quota_sync);
in particular, qd->qd_change needs to be kept in sync with the
QDF_CHANGE change flag and the number of references held. Use the
qd->qd_lockref.lock spinlock for that.
With the qd->qd_lockref.lock spinlock held, we can no longer call
lockref_get(), so turn qd_hold() into a variant that assumes that the
lock is held. This function is really supposed to take an additional
reference when one or more references are already held, so check for
that instead of checking if the lockref is dead.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
The split between qd_fish() and gfs2_quota_sync() is rather unfortunate
as qd_fish() is repeatedly called to scan sdp->sd_quota_list only to
find the next object to that needs syncing; if there are multiple
objects on the list that need syncing, it makes more sense to grab them
all in one go. This is relatively easy to do when qd_fish() is folded
into gfs2_quota_sync().
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Rename variable 'value' to 'change' as it stores a change in value.
Add new 'value' and 'limit' variables for the current value and limit.
Only fetch the tuning parameters when we need them.
Get rid of unnecessary nesting.
No change in functionality.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Function do_qc() is supposed to be conceptually simple: it alters the
current in-memory and on-disk quota change values for a given uid/gid by
a given delta. If the on-disk record isn't defined yet, a new record is
created. If the on-disk record exists and the resulting change value is
zero, there no longer is a need for that record and so the record is
deleted. On top of that, some reference counting is involved when
creating and deleting records.
Currently, instead of doing the above, do_qc() alters the on-disk value
and then it sets the in-memory value to the on-disk value. This is
incorrect when the on-disk value differs from the in-memory value. The
two values are allowed to differ when quota changes are synced to the
global quota file. Fix by changing both values by the same amount.
In addition, do_qc() currently gets confused when the delta value is 0.
It isn't supposed to be called that way, but that assumption isn't
mentioned and it makes the code harder to read. Make the code more
explicit.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Commit 432928c937 ("gfs2: Add quota_change type") makes the incorrect
assertion that function do_qc() should behave differently in the two
contexts it is used in, but that isn't actually true. In all cases,
do_qc() grabs a "reference" when it starts using a slot in the per-node
quota changes file, and it releases that "reference" when no more
residual changes remain. Revert that broken commit.
There are some remaining issues with function do_qc() which are
addressed in the next commit.
This reverts commit 432928c937.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Commit 4c6a08125f ("gfs2: ignore negated quota changes") skips quota
changes with qd_change == 0 instead of writing them back, which leaves
behind non-zero qd_change values in the affected slots. The kernel then
assumes that those slots are unused, while the qd_change values on disk
indicate that they are indeed still in use. The next time the
filesystem is mounted, those invalid slots are read in from disk, which
will cause inconsistencies.
Revert that commit to avoid filesystem corruption.
This reverts commit 4c6a08125f.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Rename qd_check_sync() to qd_grab_sync() and make it return a bool.
Turn the sync_gen pointer into a regular u64 and pass in U64_MAX instead
of a NULL pointer when sync generation checking isn't needed.
Introduce a new qd_ungrab_sync() helper for undoing the effects of
qd_grab_sync() if the subsequent bh_get() on the qd object fails.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
The qd_bh_get_or_undo() helper introduced by that commit doesn't improve
the code much, so revert it and clean things up in a more useful way in
the next commit.
This reverts commit 7dbc6ae60d.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
