As Gustavo said in other patches doing the same replace, we can now
use the new struct_size() helper to avoid leaving these open-coded and
prone to type mistake.
Signed-off-by: Zhengyuan Liu <liuzhengyuan@kylinos.cn>
Signed-off-by: David Howells <dhowells@redhat.com>
Add a couple of tracepoints to track callback management:
(1) afs_cb_miss - Logs when we were unable to apply a callback, either due
to the inode being discarded or due to a competing thread applying a
callback first.
(2) afs_cb_break - Logs when we attempted to clear the noted callback
promise, either due to the server explicitly breaking the callback,
the callback promise lapsing or a local event obsoleting it.
Signed-off-by: David Howells <dhowells@redhat.com>
Don't check that dentry->d_inode is valid in afs_unlink(). We should be
able to take that as given.
This caused Smatch to issue the following warning:
fs/afs/dir.c:1392 afs_unlink() error: we previously assumed 'vnode' could be null (see line 1375)
Reported-by: kbuild test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: David Howells <dhowells@redhat.com>
The setting of i_blocks, which is calculated from i_size, has got
accidentally misordered relative to the setting of i_size when initially
setting up an inode. Further, i_blocks isn't updated by afs_apply_status()
when the size is updated.
To fix this, break the i_size/i_blocks setting out into a helper function
and call it from both places.
Fixes: a58823ac45 ("afs: Fix application of status and callback to be under same lock")
Signed-off-by: David Howells <dhowells@redhat.com>
Fix the cb_break_lock spinlock in afs_volume struct by initialising it when
the volume record is allocated.
Also rename the lock to cb_v_break_lock to distinguish it from the lock of
the same name in the afs_server struct.
Without this, the following trace may be observed when a volume-break
callback is received:
INFO: trying to register non-static key.
the code is fine but needs lockdep annotation.
turning off the locking correctness validator.
CPU: 2 PID: 50 Comm: kworker/2:1 Not tainted 5.2.0-rc1-fscache+ #3045
Hardware name: ASUS All Series/H97-PLUS, BIOS 2306 10/09/2014
Workqueue: afs SRXAFSCB_CallBack
Call Trace:
dump_stack+0x67/0x8e
register_lock_class+0x23b/0x421
? check_usage_forwards+0x13c/0x13c
__lock_acquire+0x89/0xf73
lock_acquire+0x13b/0x166
? afs_break_callbacks+0x1b2/0x3dd
_raw_write_lock+0x2c/0x36
? afs_break_callbacks+0x1b2/0x3dd
afs_break_callbacks+0x1b2/0x3dd
? trace_event_raw_event_afs_server+0x61/0xac
SRXAFSCB_CallBack+0x11f/0x16c
process_one_work+0x2c5/0x4ee
? worker_thread+0x234/0x2ac
worker_thread+0x1d8/0x2ac
? cancel_delayed_work_sync+0xf/0xf
kthread+0x11f/0x127
? kthread_park+0x76/0x76
ret_from_fork+0x24/0x30
Fixes: 68251f0a68 ("afs: Fix whole-volume callback handling")
Signed-off-by: David Howells <dhowells@redhat.com>
Because I made the afs_call struct share pointers to an afs_server object
and an afs_vlserver object to save space, afs_put_call() calls
afs_put_server() on afs_vlserver object (which is only meant for the
afs_server object) because it sees that call->server isn't NULL.
This means that the afs_vlserver object gets unpredictably and randomly
modified, depending on what config options are set (such as lockdep).
Fix this by getting rid of the union and having two non-overlapping
pointers in the afs_call struct.
Fixes: ffba718e93 ("afs: Get rid of afs_call::reply[]")
Signed-off-by: David Howells <dhowells@redhat.com>
Occasionally, warnings like this:
vnode modified 2af7 on {10000b:1} [exp 2af2] YFS.FetchStatus(vnode)
are emitted into the kernel log. This indicates that when we were applying
the updated vnode (file) status retrieved from the server to an inode we
saw that the data version number wasn't what we were expecting (in this
case it's 0x2af7 rather than 0x2af2).
We've usually received a callback from the server prior to this point - or
the callback promise has lapsed - so the warning is merely informative and
the state is to be expected.
Fix this by only emitting the warning if the we still think that we have a
valid callback promise and haven't received a callback.
Also change the format slightly so so that the new data version doesn't
look like part of the text, the like is prefixed with "kAFS: " and the
message is ranked as a warning.
Fixes: 31143d5d51 ("AFS: implement basic file write support")
Reported-by: Ian Wienand <iwienand@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
- Build errors wrt. xattrs
- Mismerge which lead to a wrong Kconfig ifdef
- Missing endianness conversion
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Merge tag 'upstream-5.2-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifs
Pull UBIFS fixes from Richard Weinberger:
- build errors wrt xattrs
- mismerge which lead to a wrong Kconfig ifdef
- missing endianness conversion
* tag 'upstream-5.2-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/ubifs:
ubifs: Convert xattr inum to host order
ubifs: Use correct config name for encryption
ubifs: Fix build error without CONFIG_UBIFS_FS_XATTR
Merge yet more updates from Andrew Morton:
"A few final bits:
- large changes to vmalloc, yielding large performance benefits
- tweak the console-flush-on-panic code
- a few fixes"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
panic: add an option to replay all the printk message in buffer
initramfs: don't free a non-existent initrd
fs/writeback.c: use rcu_barrier() to wait for inflight wb switches going into workqueue when umount
mm/compaction.c: correct zone boundary handling when isolating pages from a pageblock
mm/vmap: add DEBUG_AUGMENT_LOWEST_MATCH_CHECK macro
mm/vmap: add DEBUG_AUGMENT_PROPAGATE_CHECK macro
mm/vmalloc.c: keep track of free blocks for vmap allocation
- remove unneeded use of cc-option, cc-disable-warning, cc-ldoption
- exclude tracked files from .gitignore
- re-enable -Wint-in-bool-context warning
- refactor samples/Makefile
- stop building immediately if syncconfig fails
- do not sprinkle error messages when $(CC) does not exist
- move arch/alpha/defconfig to the configs subdirectory
- remove crappy header search path manipulation
- add comment lines to .config to clarify the end of menu blocks
- check uniqueness of module names (adding new warnings intentionally)
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Merge tag 'kbuild-v5.2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull more Kbuild updates from Masahiro Yamada:
- remove unneeded use of cc-option, cc-disable-warning, cc-ldoption
- exclude tracked files from .gitignore
- re-enable -Wint-in-bool-context warning
- refactor samples/Makefile
- stop building immediately if syncconfig fails
- do not sprinkle error messages when $(CC) does not exist
- move arch/alpha/defconfig to the configs subdirectory
- remove crappy header search path manipulation
- add comment lines to .config to clarify the end of menu blocks
- check uniqueness of module names (adding new warnings intentionally)
* tag 'kbuild-v5.2-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (24 commits)
kconfig: use 'else ifneq' for Makefile to improve readability
kbuild: check uniqueness of module names
kconfig: Terminate menu blocks with a comment in the generated config
kbuild: add LICENSES to KBUILD_ALLDIRS
kbuild: remove 'addtree' and 'flags' magic for header search paths
treewide: prefix header search paths with $(srctree)/
media: prefix header search paths with $(srctree)/
media: remove unneeded header search paths
alpha: move arch/alpha/defconfig to arch/alpha/configs/defconfig
kbuild: terminate Kconfig when $(CC) or $(LD) is missing
kbuild: turn auto.conf.cmd into a mandatory include file
.gitignore: exclude .get_maintainer.ignore and .gitattributes
kbuild: add all Clang-specific flags unconditionally
kbuild: Don't try to add '-fcatch-undefined-behavior' flag
kbuild: add some extra warning flags unconditionally
kbuild: add -Wvla flag unconditionally
arch: remove dangling asm-generic wrappers
samples: guard sub-directories with CONFIG options
kbuild: re-enable int-in-bool-context warning
MAINTAINERS: kbuild: Add pattern for scripts/*vmlinux*
...
Unicode 12.1.0.
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Merge tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4
Pull ext4 fixes from Ted Ts'o:
"Some bug fixes, and an update to the URL's for the final version of
Unicode 12.1.0"
* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
ext4: avoid panic during forced reboot due to aborted journal
ext4: fix block validity checks for journal inodes using indirect blocks
unicode: update to Unicode 12.1.0 final
unicode: add missing check for an error return from utf8lookup()
ext4: fix miscellaneous sparse warnings
ext4: unsigned int compared against zero
ext4: fix use-after-free in dx_release()
ext4: fix data corruption caused by overlapping unaligned and aligned IO
jbd2: fix potential double free
ext4: zero out the unused memory region in the extent tree block
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Merge tag '5.2-rc-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6
Pull cifs fixes from Steve French:
"Minor cleanup and fixes, one for stable, four rdma (smbdirect)
related. Also adds SEEK_HOLE support"
* tag '5.2-rc-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6:
cifs: add support for SEEK_DATA and SEEK_HOLE
Fixed https://bugzilla.kernel.org/show_bug.cgi?id=202935 allow write on the same file
cifs: Allocate memory for all iovs in smb2_ioctl
cifs: Don't match port on SMBDirect transport
cifs:smbd Use the correct DMA direction when sending data
cifs:smbd When reconnecting to server, call smbd_destroy() after all MIDs have been called
cifs: use the right include for signal_pending()
smb3: trivial cleanup to smb2ops.c
cifs: cleanup smb2ops.c and normalize strings
smb3: display session id in debug data
synchronize_rcu() didn't wait for call_rcu() callbacks, so inode wb
switch may not go to the workqueue after synchronize_rcu(). Thus
previous scheduled switches was not finished even flushing the
workqueue, which will cause a NULL pointer dereferenced followed below.
VFS: Busy inodes after unmount of vdd. Self-destruct in 5 seconds. Have a nice day...
BUG: unable to handle kernel NULL pointer dereference at 0000000000000278
evict+0xb3/0x180
iput+0x1b0/0x230
inode_switch_wbs_work_fn+0x3c0/0x6a0
worker_thread+0x4e/0x490
? process_one_work+0x410/0x410
kthread+0xe6/0x100
ret_from_fork+0x39/0x50
Replace the synchronize_rcu() call with a rcu_barrier() to wait for all
pending callbacks to finish. And inc isw_nr_in_flight after call_rcu()
in inode_switch_wbs() to make more sense.
Link: http://lkml.kernel.org/r/20190429024108.54150-1-jiufei.xue@linux.alibaba.com
Signed-off-by: Jiufei Xue <jiufei.xue@linux.alibaba.com>
Acked-by: Tejun Heo <tj@kernel.org>
Suggested-by: Tejun Heo <tj@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently, the Kbuild core manipulates header search paths in a crazy
way [1].
To fix this mess, I want all Makefiles to add explicit $(srctree)/ to
the search paths in the srctree. Some Makefiles are already written in
that way, but not all. The goal of this work is to make the notation
consistent, and finally get rid of the gross hacks.
Having whitespaces after -I does not matter since commit 48f6e3cf5b
("kbuild: do not drop -I without parameter").
[1]: https://patchwork.kernel.org/patch/9632347/
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Handling of aborted journal is a special code path different from
standard ext4_error() one and it can call panic() as well. Commit
1dc1097ff6 ("ext4: avoid panic during forced reboot") forgot to update
this path so fix that omission.
Fixes: 1dc1097ff6 ("ext4: avoid panic during forced reboot")
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org # 5.1
Pull more vfs mount updates from Al Viro:
"Propagation of new syscalls to other architectures + cosmetic change
from Christian (fscontext didn't follow the convention for anon inode
names)"
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
uapi: Wire up the mount API syscalls on non-x86 arches [ver #2]
uapi, x86: Fix the syscall numbering of the mount API syscalls [ver #2]
uapi, fsopen: use square brackets around "fscontext" [ver #2]
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Merge tag 'afs-fixes-b-20190516' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs
Pull AFS callback promise fixes from David Howells:
"This series fixes a bunch of problems in callback promise handling,
where a callback promise indicates a promise on the part of the server
to notify the client in the event of some sort of change to a file or
volume. In the event of a break, the client has to go and refetch the
client status from the server and discard any cached permission
information as the ACL might have changed.
The problem in the current code is that changes made by other clients
aren't always noticed, primarily because the file status information
and the callback information aren't updated in the same critical
section, even if these are carried in the same reply from an RPC
operation, and so the AFS_VNODE_CB_PROMISED flag is unreliable.
Arranging for them to be done in the same critical section during
reply decoding is tricky because of the FS.InlineBulkStatus op - which
has all the statuses in the reply arriving and then all the callbacks,
so they have to be buffered. It simplifies things a lot to move the
critical section out of the decode phase and do it after the RPC
function returns.
Also new inodes (either newly fetched or newly created) aren't
properly managed against a callback break happening before we get the
local inode up and running.
Fix this by:
- There's now a combined file status and callback record (struct
afs_status_cb) to carry both plus some flags.
- Each operation wrapper function allocates sufficient afs_status_cb
records for all the vnodes it is interested in and passes them into
RPC operations to be filled in from the reply.
- The FileStatus and CallBack record decoders no longer apply the
new/revised status and callback information to the inode/vnode at
the point of decoding and instead store the information into the
record from (2).
- afs_vnode_commit_status() then revises the file status, detects
deletion and notes callback information inside of a single critical
section. It also checks the callback break counters and cancels the
callback promise if they changed during the operation.
[*] Note that "callback break counters" are counters of server
events that cancel one or more callback promises that the client
thinks it has. The client counts the events and compares the
counters before and after an operation to see if the callback
promise it thinks it just got evaporated before it got recorded
under lock.
- Volume and server callback break counters are passed into
afs_iget() allowing callback breaks concurrent with inode set up to
be detected and the callback promise thence to be cancelled.
- AFS validation checks are now done under RCU conditions using a
read lock on cb_lock. This requires vnode->cb_interest to be made
RCU safe.
- If the checks in (6) fail, the callback breaker is then called
under write lock on the cb_lock - but only if the callback break
counter didn't change from the value read before the checks were
made.
- Results from FS.InlineBulkStatus that correspond to inodes we
currently have in memory are now used to update those inodes'
status and callback information rather than being discarded. This
requires those inodes to be looked up before the RPC op is made and
all their callback break values saved.
To aid in this, the following changes have also been made:
- Don't pass the vnode into the reply delivery functions or the
decoders. The vnode shouldn't be altered anywhere in those paths.
The only exception, for the moment, is for the call done hook for
file lock ops that wants access to both the vnode and the call -
this can be fixed at a later time.
- Get rid of the call->reply[] void* array and replace it with named
and typed members. This avoids confusion since different ops were
mapping different reply[] members to different things.
- Fix an order-1 kmalloc allocation in afs_do_lookup() and replace it
with kvcalloc().
- Always get the reply time. Since callback, lock and fileserver
record expiry times are calculated for several RPCs, make this
mandatory.
- Call afs_pages_written_back() from the operation wrapper rather
than from the delivery function.
- Don't store the version and type from a callback promise in a reply
as the information in them is of very limited use"
* tag 'afs-fixes-b-20190516' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
afs: Fix application of the results of a inline bulk status fetch
afs: Pass pre-fetch server and volume break counts into afs_iget5_set()
afs: Fix unlink to handle YFS.RemoveFile2 better
afs: Clear AFS_VNODE_CB_PROMISED if we detect callback expiry
afs: Make vnode->cb_interest RCU safe
afs: Split afs_validate() so first part can be used under LOOKUP_RCU
afs: Don't save callback version and type fields
afs: Fix application of status and callback to be under same lock
afs: Always get the reply time
afs: Fix order-1 allocation in afs_do_lookup()
afs: Get rid of afs_call::reply[]
afs: Don't pass the vnode pointer through into the inline bulk status op
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Merge tag 'afs-fixes-20190516' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs
Pull misc AFS fixes from David Howells:
"This fixes a set of miscellaneous issues in the afs filesystem,
including:
- leak of keys on file close.
- broken error handling in xattr functions.
- missing locking when updating VL server list.
- volume location server DNS lookup whereby preloaded cells may not
ever get a lookup and regular DNS lookups to maintain server lists
consume power unnecessarily.
- incorrect error propagation and handling in the fileserver
iteration code causes operations to sometimes apparently succeed.
- interruption of server record check/update side op during
fileserver iteration causes uninterruptible main operations to fail
unexpectedly.
- callback promise expiry time miscalculation.
- over invalidation of the callback promise on directories.
- double locking on callback break waking up file locking waiters.
- double increment of the vnode callback break counter.
Note that it makes some changes outside of the afs code, including:
- an extra parameter to dns_query() to allow the dns_resolver key
just accessed to be immediately invalidated. AFS is caching the
results itself, so the key can be discarded.
- an interruptible version of wait_var_event().
- an rxrpc function to allow the maximum lifespan to be set on a
call.
- a way for an rxrpc call to be marked as non-interruptible"
* tag 'afs-fixes-20190516' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
afs: Fix double inc of vnode->cb_break
afs: Fix lock-wait/callback-break double locking
afs: Don't invalidate callback if AFS_VNODE_DIR_VALID not set
afs: Fix calculation of callback expiry time
afs: Make dynamic root population wait uninterruptibly for proc_cells_lock
afs: Make some RPC operations non-interruptible
rxrpc: Allow the kernel to mark a call as being non-interruptible
afs: Fix error propagation from server record check/update
afs: Fix the maximum lifespan of VL and probe calls
rxrpc: Provide kernel interface to set max lifespan on a call
afs: Fix "kAFS: AFS vnode with undefined type 0"
afs: Fix cell DNS lookup
Add wait_var_event_interruptible()
dns_resolver: Allow used keys to be invalidated
afs: Fix afs_cell records to always have a VL server list record
afs: Fix missing lock when replacing VL server list
afs: Fix afs_xattr_get_yfs() to not try freeing an error value
afs: Fix incorrect error handling in afs_xattr_get_acl()
afs: Fix key leak in afs_release() and afs_evict_inode()
- a fix to enforce quotas set above the mount point (Luis Henriques)
- support for exporting snapshots through NFS (Zheng Yan)
- proper statx implementation (Jeff Layton). statx flags are mapped
to MDS caps, with AT_STATX_{DONT,FORCE}_SYNC taken into account.
- some follow-up dentry name handling fixes, in particular elimination
of our hand-rolled helper and the switch to __getname() as suggested
by Al (Jeff Layton)
- a set of MDS client cleanups in preparation for async MDS requests
in the future (Jeff Layton)
- a fix to sync the filesystem before remounting (Jeff Layton)
On the rbd side, work is on-going on object-map and fast-diff image
features.
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Merge tag 'ceph-for-5.2-rc1' of git://github.com/ceph/ceph-client
Pull ceph updates from Ilya Dryomov:
"On the filesystem side we have:
- a fix to enforce quotas set above the mount point (Luis Henriques)
- support for exporting snapshots through NFS (Zheng Yan)
- proper statx implementation (Jeff Layton). statx flags are mapped
to MDS caps, with AT_STATX_{DONT,FORCE}_SYNC taken into account.
- some follow-up dentry name handling fixes, in particular
elimination of our hand-rolled helper and the switch to __getname()
as suggested by Al (Jeff Layton)
- a set of MDS client cleanups in preparation for async MDS requests
in the future (Jeff Layton)
- a fix to sync the filesystem before remounting (Jeff Layton)
On the rbd side, work is on-going on object-map and fast-diff image
features"
* tag 'ceph-for-5.2-rc1' of git://github.com/ceph/ceph-client: (29 commits)
ceph: flush dirty inodes before proceeding with remount
ceph: fix unaligned access in ceph_send_cap_releases
libceph: make ceph_pr_addr take an struct ceph_entity_addr pointer
libceph: fix unaligned accesses in ceph_entity_addr handling
rbd: don't assert on writes to snapshots
rbd: client_mutex is never nested
ceph: print inode number in __caps_issued_mask debugging messages
ceph: just call get_session in __ceph_lookup_mds_session
ceph: simplify arguments and return semantics of try_get_cap_refs
ceph: fix comment over ceph_drop_caps_for_unlink
ceph: move wait for mds request into helper function
ceph: have ceph_mdsc_do_request call ceph_mdsc_submit_request
ceph: after an MDS request, do callback and completions
ceph: use pathlen values returned by set_request_path_attr
ceph: use __getname/__putname in ceph_mdsc_build_path
ceph: use ceph_mdsc_build_path instead of clone_dentry_name
ceph: fix potential use-after-free in ceph_mdsc_build_path
ceph: dump granular cap info in "caps" debugfs file
ceph: make iterate_session_caps a public symbol
ceph: fix NULL pointer deref when debugging is enabled
...
Fix afs_do_lookup() such that when it does an inline bulk status fetch op,
it will update inodes that are already extant (something that afs_iget()
doesn't do) and to cache permits for each inode created (thereby avoiding a
follow up FS.FetchStatus call to determine this).
Extant inodes need looking up in advance so that their cb_break counters
before and after the operation can be compared. To this end, the inode
pointers are cached so that they don't need looking up again after the op.
Fixes: 5cf9dd55a0 ("afs: Prospectively look up extra files when doing a single lookup")
Signed-off-by: David Howells <dhowells@redhat.com>
Pass the server and volume break counts from before the status fetch
operation that queried the attributes of a file into afs_iget5_set() so
that the new vnode's break counters can be initialised appropriately.
This allows detection of a volume or server break that happened whilst we
were fetching the status or setting up the vnode.
Fixes: c435ee3455 ("afs: Overhaul the callback handling")
Signed-off-by: David Howells <dhowells@redhat.com>
Make use of the status update for the target file that the YFS.RemoveFile2
RPC op returns to correctly update the vnode as to whether the file was
actually deleted or just had nlink reduced.
Fixes: 30062bd13e ("afs: Implement YFS support in the fs client")
Signed-off-by: David Howells <dhowells@redhat.com>
Fix afs_validate() to clear AFS_VNODE_CB_PROMISED on a vnode if we detect
any condition that causes the callback promise to be broken implicitly,
including server break (cb_s_break), volume break (cb_v_break) or callback
expiry.
Fixes: ae3b7361dc ("afs: Fix validation/callback interaction")
Reported-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Use RCU-based freeing for afs_cb_interest struct objects and use RCU on
vnode->cb_interest. Use that change to allow afs_check_validity() to use
read_seqbegin_or_lock() instead of read_seqlock_excl().
This also requires the caller of afs_check_validity() to hold the RCU read
lock across the call.
Signed-off-by: David Howells <dhowells@redhat.com>
Split afs_validate() so that the part that decides if the vnode is still
valid can be used under LOOKUP_RCU conditions from afs_d_revalidate().
Signed-off-by: David Howells <dhowells@redhat.com>
Don't save callback version and type fields as the version is about the
format of the callback information and the type is relative to the
particular RPC call.
Signed-off-by: David Howells <dhowells@redhat.com>
- a fix for an error path use after free (YueHaibing)
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Merge tag 'configfs-for-5.2' of git://git.infradead.org/users/hch/configfs
Pull configfs update from Christoph Hellwig:
- a fix for an error path use after free (YueHaibing)
* tag 'configfs-for-5.2' of git://git.infradead.org/users/hch/configfs:
configfs: fix possible use-after-free in configfs_register_group
Make the name of the anon inode fd "[fscontext]" instead of "fscontext".
This is minor but most core-kernel anon inode fds already carry square
brackets around their name:
[eventfd]
[eventpoll]
[fanotify]
[io_uring]
[pidfd]
[signalfd]
[timerfd]
[userfaultfd]
For the sake of consistency lets do the same for the fscontext anon inode
fd that comes with the new mount api.
Signed-off-by: Christian Brauner <christian@brauner.io>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
When __afs_break_callback() clears the CB_PROMISED flag, it increments
vnode->cb_break to trigger a future refetch of the status and callback -
however it also calls afs_clear_permits(), which also increments
vnode->cb_break.
Fix this by removing the increment from afs_clear_permits().
Whilst we're at it, fix the conditional call to afs_put_permits() as the
function checks to see if the argument is NULL, so the check is redundant.
Fixes: be080a6f43 ("afs: Overhaul permit caching");
Signed-off-by: David Howells <dhowells@redhat.com>
When applying the status and callback in the response of an operation,
apply them in the same critical section so that there's no race between
checking the callback state and checking status-dependent state (such as
the data version).
Fix this by:
(1) Allocating a joint {status,callback} record (afs_status_cb) before
calling the RPC function for each vnode for which the RPC reply
contains a status or a status plus a callback. A flag is set in the
record to indicate if a callback was actually received.
(2) These records are passed into the RPC functions to be filled in. The
afs_decode_status() and yfs_decode_status() functions are removed and
the cb_lock is no longer taken.
(3) xdr_decode_AFSFetchStatus() and xdr_decode_YFSFetchStatus() no longer
update the vnode.
(4) xdr_decode_AFSCallBack() and xdr_decode_YFSCallBack() no longer update
the vnode.
(5) vnodes, expected data-version numbers and callback break counters
(cb_break) no longer need to be passed to the reply delivery
functions.
Note that, for the moment, the file locking functions still need
access to both the call and the vnode at the same time.
(6) afs_vnode_commit_status() is now given the cb_break value and the
expected data_version and the task of applying the status and the
callback to the vnode are now done here.
This is done under a single taking of vnode->cb_lock.
(7) afs_pages_written_back() is now called by afs_store_data() rather than
by the reply delivery function.
afs_pages_written_back() has been moved to before the call point and
is now given the first and last page numbers rather than a pointer to
the call.
(8) The indicator from YFS.RemoveFile2 as to whether the target file
actually got removed (status.abort_code == VNOVNODE) rather than
merely dropping a link is now checked in afs_unlink rather than in
xdr_decode_YFSFetchStatus().
Supplementary fixes:
(*) afs_cache_permit() now gets the caller_access mask from the
afs_status_cb object rather than picking it out of the vnode's status
record. afs_fetch_status() returns caller_access through its argument
list for this purpose also.
(*) afs_inode_init_from_status() now uses a write lock on cb_lock rather
than a read lock and now sets the callback inside the same critical
section.
Fixes: c435ee3455 ("afs: Overhaul the callback handling")
Signed-off-by: David Howells <dhowells@redhat.com>
__afs_break_callback() holds vnode->lock around its call of
afs_lock_may_be_available() - which also takes that lock.
Fix this by not taking the lock in __afs_break_callback().
Also, there's no point checking the granted_locks and pending_locks queues;
it's sufficient to check lock_state, so move that check out of
afs_lock_may_be_available() into __afs_break_callback() to replace the
queue checks.
Fixes: e8d6c55412 ("AFS: implement file locking")
Signed-off-by: David Howells <dhowells@redhat.com>
Always ask for the reply time from AF_RXRPC as it's used to calculate the
callback expiry time and lock expiry times, so it's needed by most FS
operations.
Signed-off-by: David Howells <dhowells@redhat.com>
Don't invalidate the callback promise on a directory if the
AFS_VNODE_DIR_VALID flag is not set (which indicates that the directory
contents are invalid, due to edit failure, callback break, page reclaim).
The directory will be reloaded next time the directory is accessed, so
clearing the callback flag at this point may race with a reload of the
directory and cancel it's recorded callback promise.
Fixes: f3ddee8dc4 ("afs: Fix directory handling")
Signed-off-by: David Howells <dhowells@redhat.com>
afs_do_lookup() will do an order-1 allocation to allocate status records if
there are more than 39 vnodes to stat.
Fix this by allocating an array of {status,callback} records for each vnode
we want to examine using vmalloc() if larger than a page.
This not only gets rid of the order-1 allocation, but makes it easier to
grow beyond 50 records for YFS servers. It also allows us to move to
{status,callback} tuples for other calls too and makes it easier to lock
across the application of the status and the callback to the vnode.
Fixes: 5cf9dd55a0 ("afs: Prospectively look up extra files when doing a single lookup")
Signed-off-by: David Howells <dhowells@redhat.com>
Fix the calculation of the expiry time of a callback promise, as obtained
from operations like FS.FetchStatus and FS.FetchData.
The time should be based on the timestamp of the first DATA packet in the
reply and the calculation needs to turn the ktime_t timestamp into a
time64_t.
Fixes: c435ee3455 ("afs: Overhaul the callback handling")
Signed-off-by: David Howells <dhowells@redhat.com>
Replace the afs_call::reply[] array with a bunch of typed members so that
the compiler can use type-checking on them. It's also easier for the eye
to see what's going on.
Signed-off-by: David Howells <dhowells@redhat.com>
Don't pass the vnode pointer through into the inline bulk status op. We
want to process the status records outside of it anyway.
Signed-off-by: David Howells <dhowells@redhat.com>
Make certain RPC operations non-interruptible, including:
(*) Set attributes
(*) Store data
We don't want to get interrupted during a flush on close, flush on
unlock, writeback or an inode update, leaving us in a state where we
still need to do the writeback or update.
(*) Extend lock
(*) Release lock
We don't want to get lock extension interrupted as the file locks on
the server are time-limited. Interruption during lock release is less
of an issue since the lock is time-limited, but it's better to
complete the release to avoid a several-minute wait to recover it.
*Setting* the lock isn't a problem if it's interrupted since we can
just return to the user and tell them they were interrupted - at
which point they can elect to retry.
(*) Silly unlink
We want to remove silly unlink files if we can, rather than leaving
them for the salvager to clear up.
Note that whilst these calls are no longer interruptible, they do have
timeouts on them, so if the server stops responding the call will fail with
something like ETIME or ECONNRESET.
Without this, the following:
kAFS: Unexpected error from FS.StoreData -512
appears in dmesg when a pending store data gets interrupted and some
processes may just hang.
Additionally, make the code that checks/updates the server record ignore
failure due to interruption if the main call is uninterruptible and if the
server has an address list. The next op will check it again since the
expiration time on the old list has past.
Fixes: d2ddc776a4 ("afs: Overhaul volume and server record caching and fileserver rotation")
Reported-by: Jonathan Billings <jsbillings@jsbillings.org>
Reported-by: Marc Dionne <marc.dionne@auristor.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Allow kernel services using AF_RXRPC to indicate that a call should be
non-interruptible. This allows kafs to make things like lock-extension and
writeback data storage calls non-interruptible.
If this is set, signals will be ignored for operations on that call where
possible - such as waiting to get a call channel on an rxrpc connection.
It doesn't prevent UDP sendmsg from being interrupted, but that will be
handled by packet retransmission.
rxrpc_kernel_recv_data() isn't affected by this since that never waits,
preferring instead to return -EAGAIN and leave the waiting to the caller.
Userspace initiated calls can't be set to be uninterruptible at this time.
Signed-off-by: David Howells <dhowells@redhat.com>
afs_check/update_server_record() should be setting fc->error rather than
fc->ac.error as they're called from within the cursor iteration function.
afs_fs_cursor::error is where the error code of the attempt to call the
operation on multiple servers is integrated and is the final result,
whereas afs_addr_cursor::error is used to hold the error from individual
iterations of the call loop. (Note there's also an afs_vl_cursor which
also wraps afs_addr_cursor for accessing VL servers rather than file
servers).
Fix this by setting fc->error in the afs_check/update_server_record() so
that any error incurred whilst talking to the VL server correctly
propagates to the final result.
This results in:
kAFS: Unexpected error from FS.StoreData -512
being seen, even though the store-data op is non-interruptible. The error
is actually coming from the server record update getting interrupted.
Fixes: d2ddc776a4 ("afs: Overhaul volume and server record caching and fileserver rotation")
Signed-off-by: David Howells <dhowells@redhat.com>
If an older AFS server doesn't support an operation, it may accept the call
and then sit on it forever, happily responding to pings that make kafs
think that the call is still alive.
Fix this by setting the maximum lifespan of Volume Location service calls
in particular and probe calls in general so that they don't run on
endlessly if they're not supported.
Signed-off-by: David Howells <dhowells@redhat.com>
Under some circumstances afs_select_fileserver() can return without setting
an error in fc->error. The problem is in the no_more_servers segment where
the accumulated errors from attempts to contact various servers are
integrated into an afs_error-type variable 'e'. The resultant error code
is, however, then abandoned.
Fix this by getting the error out of e.error and putting it in 'error' so
that the next part will store it into fc->error.
Not doing this causes a report like the following:
kAFS: AFS vnode with undefined type 0
kAFS: A=0 m=0 s=0 v=0
kAFS: vnode 20000025:1:1
because the code following the server selection loop then sees what it
thinks is a successful invocation because fc.error is 0. However, it can't
apply the status record because it's all zeros.
The report is followed on the first instance with a trace looking something
like:
dump_stack+0x67/0x8e
afs_inode_init_from_status.isra.2+0x21b/0x487
afs_fetch_status+0x119/0x1df
afs_iget+0x130/0x295
afs_get_tree+0x31d/0x595
vfs_get_tree+0x1f/0xe8
fc_mount+0xe/0x36
afs_d_automount+0x328/0x3c3
follow_managed+0x109/0x20a
lookup_fast+0x3bf/0x3f8
do_last+0xc3/0x6a4
path_openat+0x1af/0x236
do_filp_open+0x51/0xae
? _raw_spin_unlock+0x24/0x2d
? __alloc_fd+0x1a5/0x1b7
do_sys_open+0x13b/0x1e8
do_syscall_64+0x7d/0x1b3
entry_SYSCALL_64_after_hwframe+0x49/0xbe
Fixes: 4584ae96ae ("afs: Fix missing net error handling")
Signed-off-by: David Howells <dhowells@redhat.com>
The previous patch has ensured that io_cqring_events contain
smp_rmb memory barriers, Now we can use wait_event_interruptible
to keep the code simple.
Signed-off-by: Jackie Liu <liuyun01@kylinos.cn>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Whenever smp_rmb is required to use io_cqring_events,
keep smp_rmb inside the function io_cqring_events.
Signed-off-by: Jackie Liu <liuyun01@kylinos.cn>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This fixes couple of races which lead to infinite wait of park completion
with the following backtraces:
[20801.303319] Call Trace:
[20801.303321] ? __schedule+0x284/0x650
[20801.303323] schedule+0x33/0xc0
[20801.303324] schedule_timeout+0x1bc/0x210
[20801.303326] ? schedule+0x3d/0xc0
[20801.303327] ? schedule_timeout+0x1bc/0x210
[20801.303329] ? preempt_count_add+0x79/0xb0
[20801.303330] wait_for_completion+0xa5/0x120
[20801.303331] ? wake_up_q+0x70/0x70
[20801.303333] kthread_park+0x48/0x80
[20801.303335] io_finish_async+0x2c/0x70
[20801.303336] io_ring_ctx_wait_and_kill+0x95/0x180
[20801.303338] io_uring_release+0x1c/0x20
[20801.303339] __fput+0xad/0x210
[20801.303341] task_work_run+0x8f/0xb0
[20801.303342] exit_to_usermode_loop+0xa0/0xb0
[20801.303343] do_syscall_64+0xe0/0x100
[20801.303349] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[20801.303380] Call Trace:
[20801.303383] ? __schedule+0x284/0x650
[20801.303384] schedule+0x33/0xc0
[20801.303386] io_sq_thread+0x38a/0x410
[20801.303388] ? __switch_to_asm+0x40/0x70
[20801.303390] ? wait_woken+0x80/0x80
[20801.303392] ? _raw_spin_lock_irqsave+0x17/0x40
[20801.303394] ? io_submit_sqes+0x120/0x120
[20801.303395] kthread+0x112/0x130
[20801.303396] ? kthread_create_on_node+0x60/0x60
[20801.303398] ret_from_fork+0x35/0x40
o kthread_park() waits for park completion, so io_sq_thread() loop
should check kthread_should_park() along with khread_should_stop(),
otherwise if kthread_park() is called before prepare_to_wait()
the following schedule() never returns:
CPU#0 CPU#1
io_sq_thread_stop(): io_sq_thread():
while(!kthread_should_stop() && !ctx->sqo_stop) {
ctx->sqo_stop = 1;
kthread_park()
prepare_to_wait();
if (kthread_should_stop() {
}
schedule(); <<< nobody checks park flag,
<<< so schedule and never return
o if the flag ctx->sqo_stop is observed by the io_sq_thread() loop
it is quite possible, that kthread_should_park() check and the
following kthread_parkme() is never called, because kthread_park()
has not been yet called, but few moments later is is called and
waits there for park completion, which never happens, because
kthread has already exited:
CPU#0 CPU#1
io_sq_thread_stop(): io_sq_thread():
ctx->sqo_stop = 1;
while(!kthread_should_stop() && !ctx->sqo_stop) {
<<< observe sqo_stop and exit the loop
}
if (kthread_should_park())
kthread_parkme(); <<< never called, since was
<<< never parked
kthread_park() <<< waits forever for park completion
In the current patch we quit the loop by only kthread_should_park()
check (kthread_park() is synchronous, so kthread_should_stop() is
never observed), and we abandon ->sqo_stop flag, since it is racy.
At the end of the io_sq_thread() we unconditionally call parmke(),
since we've exited the loop by the park flag.
Signed-off-by: Roman Penyaev <rpenyaev@suse.de>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Currently, once configured, AFS cells are looked up in the DNS at regular
intervals - which is a waste of resources if those cells aren't being
used. It also leads to a problem where cells preloaded, but not
configured, before the network is brought up end up effectively statically
configured with no VL servers and are unable to get any.
Fix this by not doing the DNS lookup until the first time a cell is
touched. It is waited for if we don't have any cached records yet,
otherwise the DNS lookup to maintain the record is done in the background.
This has the downside that the first time you touch a cell, you now have to
wait for the upcall to do the required DNS lookups rather than them already
being cached.
Further, the record is not replaced if the old record has at least one
server in it and the new record doesn't have any.
Fixes: 0a5143f2f8 ("afs: Implement VL server rotation")
Signed-off-by: David Howells <dhowells@redhat.com>
