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path: root/fs/nfsd/nfs4state.c
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2024-08-19nfsd: make all of the nfsd stats per-network namespaceJosef Bacik
[ Upstream commit 4b14885411f74b2b0ce0eb2b39d0fffe54e5ca0d ] We have a global set of counters that we modify for all of the nfsd operations, but now that we're exposing these stats across all network namespaces we need to make the stats also be per-network namespace. We already have some caching stats that are per-network namespace, so move these definitions into the same counter and then adjust all the helpers and users of these stats to provide the appropriate nfsd_net struct so that the stats are maintained for the per-network namespace objects. Signed-off-by: Josef Bacik <josef@toxicpanda.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-04-10nfsd: hold a lighter-weight client reference over CB_RECALL_ANYJeff Layton
[ Upstream commit 10396f4df8b75ff6ab0aa2cd74296565466f2c8d ] Currently the CB_RECALL_ANY job takes a cl_rpc_users reference to the client. While a callback job is technically an RPC that counter is really more for client-driven RPCs, and this has the effect of preventing the client from being unhashed until the callback completes. If nfsd decides to send a CB_RECALL_ANY just as the client reboots, we can end up in a situation where the callback can't complete on the (now dead) callback channel, but the new client can't connect because the old client can't be unhashed. This usually manifests as a NFS4ERR_DELAY return on the CREATE_SESSION operation. The job is only holding a reference to the client so it can clear a flag after the RPC completes. Fix this by having CB_RECALL_ANY instead hold a reference to the cl_nfsdfs.cl_ref. Typically we only take that sort of reference when dealing with the nfsdfs info files, but it should work appropriately here to ensure that the nfs4_client doesn't disappear. Fixes: 44df6f439a17 ("NFSD: add delegation reaper to react to low memory condition") Reported-by: Vladimir Benes <vbenes@redhat.com> Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-02-23nfsd: don't take fi_lock in nfsd_break_deleg_cb()NeilBrown
commit 5ea9a7c5fe4149f165f0e3b624fe08df02b6c301 upstream. A recent change to check_for_locks() changed it to take ->flc_lock while holding ->fi_lock. This creates a lock inversion (reported by lockdep) because there is a case where ->fi_lock is taken while holding ->flc_lock. ->flc_lock is held across ->fl_lmops callbacks, and nfsd_break_deleg_cb() is one of those and does take ->fi_lock. However it doesn't need to. Prior to v4.17-rc1~110^2~22 ("nfsd: create a separate lease for each delegation") nfsd_break_deleg_cb() would walk the ->fi_delegations list and so needed the lock. Since then it doesn't walk the list and doesn't need the lock. Two actions are performed under the lock. One is to call nfsd_break_one_deleg which calls nfsd4_run_cb(). These doesn't act on the nfs4_file at all, so don't need the lock. The other is to set ->fi_had_conflict which is in the nfs4_file. This field is only ever set here (except when initialised to false) so there is no possible problem will multiple threads racing when setting it. The field is tested twice in nfs4_set_delegation(). The first test does not hold a lock and is documented as an opportunistic optimisation, so it doesn't impose any need to hold ->fi_lock while setting ->fi_had_conflict. The second test in nfs4_set_delegation() *is* make under ->fi_lock, so removing the locking when ->fi_had_conflict is set could make a change. The change could only be interesting if ->fi_had_conflict tested as false even though nfsd_break_one_deleg() ran before ->fi_lock was unlocked. i.e. while hash_delegation_locked() was running. As hash_delegation_lock() doesn't interact in any way with nfs4_run_cb() there can be no importance to this interaction. So this patch removes the locking from nfsd_break_one_deleg() and moves the final test on ->fi_had_conflict out of the locked region to make it clear that locking isn't important to the test. It is still tested *after* vfs_setlease() has succeeded. This might be significant and as vfs_setlease() takes ->flc_lock, and nfsd_break_one_deleg() is called under ->flc_lock this "after" is a true ordering provided by a spinlock. Fixes: edcf9725150e ("nfsd: fix RELEASE_LOCKOWNER") Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-31nfsd: fix RELEASE_LOCKOWNERNeilBrown
commit edcf9725150e42beeca42d085149f4c88fa97afd upstream. The test on so_count in nfsd4_release_lockowner() is nonsense and harmful. Revert to using check_for_locks(), changing that to not sleep. First: harmful. As is documented in the kdoc comment for nfsd4_release_lockowner(), the test on so_count can transiently return a false positive resulting in a return of NFS4ERR_LOCKS_HELD when in fact no locks are held. This is clearly a protocol violation and with the Linux NFS client it can cause incorrect behaviour. If RELEASE_LOCKOWNER is sent while some other thread is still processing a LOCK request which failed because, at the time that request was received, the given owner held a conflicting lock, then the nfsd thread processing that LOCK request can hold a reference (conflock) to the lock owner that causes nfsd4_release_lockowner() to return an incorrect error. The Linux NFS client ignores that NFS4ERR_LOCKS_HELD error because it never sends NFS4_RELEASE_LOCKOWNER without first releasing any locks, so it knows that the error is impossible. It assumes the lock owner was in fact released so it feels free to use the same lock owner identifier in some later locking request. When it does reuse a lock owner identifier for which a previous RELEASE failed, it will naturally use a lock_seqid of zero. However the server, which didn't release the lock owner, will expect a larger lock_seqid and so will respond with NFS4ERR_BAD_SEQID. So clearly it is harmful to allow a false positive, which testing so_count allows. The test is nonsense because ... well... it doesn't mean anything. so_count is the sum of three different counts. 1/ the set of states listed on so_stateids 2/ the set of active vfs locks owned by any of those states 3/ various transient counts such as for conflicting locks. When it is tested against '2' it is clear that one of these is the transient reference obtained by find_lockowner_str_locked(). It is not clear what the other one is expected to be. In practice, the count is often 2 because there is precisely one state on so_stateids. If there were more, this would fail. In my testing I see two circumstances when RELEASE_LOCKOWNER is called. In one case, CLOSE is called before RELEASE_LOCKOWNER. That results in all the lock states being removed, and so the lockowner being discarded (it is removed when there are no more references which usually happens when the lock state is discarded). When nfsd4_release_lockowner() finds that the lock owner doesn't exist, it returns success. The other case shows an so_count of '2' and precisely one state listed in so_stateid. It appears that the Linux client uses a separate lock owner for each file resulting in one lock state per lock owner, so this test on '2' is safe. For another client it might not be safe. So this patch changes check_for_locks() to use the (newish) find_any_file_locked() so that it doesn't take a reference on the nfs4_file and so never calls nfsd_file_put(), and so never sleeps. With this check is it safe to restore the use of check_for_locks() rather than testing so_count against the mysterious '2'. Fixes: ce3c4ad7f4ce ("NFSD: Fix possible sleep during nfsd4_release_lockowner()") Signed-off-by: NeilBrown <neilb@suse.de> Reviewed-by: Jeff Layton <jlayton@kernel.org> Cc: stable@vger.kernel.org # v6.2+ Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-11-28nfsd: fix file memleak on client_opens_releaseMahmoud Adam
commit bc1b5acb40201a0746d68a7d7cfc141899937f4f upstream. seq_release should be called to free the allocated seq_file Cc: stable@vger.kernel.org # v5.3+ Signed-off-by: Mahmoud Adam <mngyadam@amazon.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Fixes: 78599c42ae3c ("nfsd4: add file to display list of client's opens") Reviewed-by: NeilBrown <neilb@suse.de> Tested-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-29NFSD: Enable write delegation supportDai Ngo
This patch grants write delegations for OPEN with NFS4_SHARE_ACCESS_WRITE if there is no conflict with other OPENs. Write delegation conflicts with another OPEN, REMOVE, RENAME and SETATTR are handled the same as read delegation using notify_change, try_break_deleg. The NFSv4.0 protocol does not enable a server to determine that a conflicting GETATTR originated from the client holding the delegation versus coming from some other client. With NFSv4.1 and later, the SEQUENCE operation that begins each COMPOUND contains a client ID, so delegation recall can be safely squelched in this case. With NFSv4.0, however, the server must recall or send a CB_GETATTR (per RFC 7530 Section 16.7.5) even when the GETATTR originates from the client holding that delegation. An NFSv4.0 client can trigger a pathological situation if it always sends a DELEGRETURN preceded by a conflicting GETATTR in the same COMPOUND. COMPOUND execution will always stop at the GETATTR and the DELEGRETURN will never get executed. The server eventually revokes the delegation, which can result in loss of open or lock state. Tracepoint added to track whether read or write delegation is granted. Signed-off-by: Dai Ngo <dai.ngo@oracle.com> Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-08-29NFSD: handle GETATTR conflict with write delegationDai Ngo
If the GETATTR request on a file that has write delegation in effect and the request attributes include the change info and size attribute then the write delegation is recalled. If the delegation is returned within 30ms then the GETATTR is serviced as normal otherwise the NFS4ERR_DELAY error is returned for the GETATTR. Add counter for write delegation recall due to conflict GETATTR. This is used to evaluate the need to implement CB_GETATTR to adoid recalling the delegation with conflit GETATTR. Signed-off-by: Dai Ngo <dai.ngo@oracle.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-08-04nfsd: Fix race to FREE_STATEID and cl_revokedBenjamin Coddington
We have some reports of linux NFS clients that cannot satisfy a linux knfsd server that always sets SEQ4_STATUS_RECALLABLE_STATE_REVOKED even though those clients repeatedly walk all their known state using TEST_STATEID and receive NFS4_OK for all. Its possible for revoke_delegation() to set NFS4_REVOKED_DELEG_STID, then nfsd4_free_stateid() finds the delegation and returns NFS4_OK to FREE_STATEID. Afterward, revoke_delegation() moves the same delegation to cl_revoked. This would produce the observed client/server effect. Fix this by ensuring that the setting of sc_type to NFS4_REVOKED_DELEG_STID and move to cl_revoked happens within the same cl_lock. This will allow nfsd4_free_stateid() to properly remove the delegation from cl_revoked. Link: https://bugzilla.redhat.com/show_bug.cgi?id=2217103 Link: https://bugzilla.redhat.com/show_bug.cgi?id=2176575 Signed-off-by: Benjamin Coddington <bcodding@redhat.com> Cc: stable@vger.kernel.org # v4.17+ Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-07-18nfsd: Remove incorrect check in nfsd4_validate_stateidTrond Myklebust
If the client is calling TEST_STATEID, then it is because some event occurred that requires it to check all the stateids for validity and call FREE_STATEID on the ones that have been revoked. In this case, either the stateid exists in the list of stateids associated with that nfs4_client, in which case it should be tested, or it does not. There are no additional conditions to be considered. Reported-by: "Frank Ch. Eigler" <fche@redhat.com> Fixes: 7df302f75ee2 ("NFSD: TEST_STATEID should not return NFS4ERR_STALE_STATEID") Cc: stable@vger.kernel.org # v5.7+ Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-02-22Merge tag 'nfsd-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linuxLinus Torvalds
Pull nfsd updates from Chuck Lever: "Two significant security enhancements are part of this release: - NFSD's RPC header encoding and decoding, including RPCSEC GSS and gssproxy header parsing, has been overhauled to make it more memory-safe. - Support for Kerberos AES-SHA2-based encryption types has been added for both the NFS client and server. This provides a clean path for deprecating and removing insecure encryption types based on DES and SHA-1. AES-SHA2 is also FIPS-140 compliant, so that NFS with Kerberos may now be used on systems with fips enabled. In addition to these, NFSD is now able to handle crossing into an auto-mounted mount point on an exported NFS mount. A number of fixes have been made to NFSD's server-side copy implementation. RPC metrics have been converted to per-CPU variables. This helps reduce unnecessary cross-CPU and cross-node memory bus traffic, and significantly reduces noise when KCSAN is enabled" * tag 'nfsd-6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux: (121 commits) NFSD: Clean up nfsd_symlink() NFSD: copy the whole verifier in nfsd_copy_write_verifier nfsd: don't fsync nfsd_files on last close SUNRPC: Fix occasional warning when destroying gss_krb5_enctypes nfsd: fix courtesy client with deny mode handling in nfs4_upgrade_open NFSD: fix problems with cleanup on errors in nfsd4_copy nfsd: fix race to check ls_layouts nfsd: don't hand out delegation on setuid files being opened for write SUNRPC: Remove ->xpo_secure_port() SUNRPC: Clean up the svc_xprt_flags() macro nfsd: remove fs/nfsd/fault_inject.c NFSD: fix leaked reference count of nfsd4_ssc_umount_item nfsd: clean up potential nfsd_file refcount leaks in COPY codepath nfsd: zero out pointers after putting nfsd_files on COPY setup error SUNRPC: Fix whitespace damage in svcauth_unix.c nfsd: eliminate __nfs4_get_fd nfsd: add some kerneldoc comments for stateid preprocessing functions nfsd: eliminate find_deleg_file_locked nfsd: don't take nfsd4_copy ref for OP_OFFLOAD_STATUS SUNRPC: Add encryption self-tests ...
2023-02-20Merge tag 'locks-v6.3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux Pull file locking updates from Jeff Layton: "The main change here is that I've broken out most of the file locking definitions into a new header file. I also went ahead and completed the removal of locks_inode function" * tag 'locks-v6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/jlayton/linux: fs: remove locks_inode filelock: move file locking definitions to separate header file
2023-02-20nfsd: fix courtesy client with deny mode handling in nfs4_upgrade_openJeff Layton
The nested if statements here make no sense, as you can never reach "else" branch in the nested statement. Fix the error handling for when there is a courtesy client that holds a conflicting deny mode. Fixes: 3d6942715180 ("NFSD: add support for share reservation conflict to courteous server") Reported-by: 張智諺 <cc85nod@gmail.com> Signed-off-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Dai Ngo <dai.ngo@oracle.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-02-20NFSD: fix problems with cleanup on errors in nfsd4_copyDai Ngo
When nfsd4_copy fails to allocate memory for async_copy->cp_src, or nfs4_init_copy_state fails, it calls cleanup_async_copy to do the cleanup for the async_copy which causes page fault since async_copy is not yet initialized. This patche rearranges the order of initializing the fields in async_copy and adds checks in cleanup_async_copy to skip un-initialized fields. Fixes: ce0887ac96d3 ("NFSD add nfs4 inter ssc to nfsd4_copy") Fixes: 87689df69491 ("NFSD: Shrink size of struct nfsd4_copy") Signed-off-by: Dai Ngo <dai.ngo@oracle.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-02-20nfsd: don't hand out delegation on setuid files being opened for writeJeff Layton
We had a bug report that xfstest generic/355 was failing on NFSv4.0. This test sets various combinations of setuid/setgid modes and tests whether DIO writes will cause them to be stripped. What I found was that the server did properly strip those bits, but the client didn't notice because it held a delegation that was not recalled. The recall didn't occur because the client itself was the one generating the activity and we avoid recalls in that case. Clearing setuid bits is an "implicit" activity. The client didn't specifically request that we do that, so we need the server to issue a CB_RECALL, or avoid the situation entirely by not issuing a delegation. The easiest fix here is to simply not give out a delegation if the file is being opened for write, and the mode has the setuid and/or setgid bit set. Note that there is a potential race between the mode and lease being set, so we test for this condition both before and after setting the lease. This patch fixes generic/355, generic/683 and generic/684 for me. (Note that 355 fails only on v4.0, and 683 and 684 require NFSv4.2 to run and fail). Reported-by: Boyang Xue <bxue@redhat.com> Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-02-20nfsd: eliminate __nfs4_get_fdJeff Layton
This is wrapper is pointless, and just obscures what's going on. Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-02-20nfsd: add some kerneldoc comments for stateid preprocessing functionsJeff Layton
Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-02-20nfsd: eliminate find_deleg_file_lockedJeff Layton
We really don't need an accessor function here. Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-02-20nfsd: fix potential race in nfs4_find_fileJeff Layton
The WARN_ON_ONCE check is not terribly useful. It also seems possible for nfs4_find_file to race with the destruction of an fi_deleg_file while trying to take a reference to it. Now that it's safe to pass nfs_get_file a NULL pointer, remove the WARN and NULL pointer check. Take the fi_lock when fetching fi_deleg_file. Cc: NeilBrown <neilb@suse.de> Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-02-20nfsd: allow nfsd_file_get to sanely handle a NULL pointerJeff Layton
...and remove some now-useless NULL pointer checks in its callers. Suggested-by: NeilBrown <neilb@suse.de> Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-02-15Merge tag 'nfsd-6.2-6' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux Pull nfsd fix from Chuck Lever: - Fix a teardown bug in the new nfs4_file hashtable * tag 'nfsd-6.2-6' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux: nfsd: don't destroy global nfs4_file table in per-net shutdown
2023-02-11nfsd: don't destroy global nfs4_file table in per-net shutdownJeff Layton
The nfs4_file table is global, so shutting it down when a containerized nfsd is shut down is wrong and can lead to double-frees. Tear down the nfs4_file_rhltable in nfs4_state_shutdown instead of nfs4_state_shutdown_net. Fixes: d47b295e8d76 ("NFSD: Use rhashtable for managing nfs4_file objects") Link: https://bugzilla.redhat.com/show_bug.cgi?id=2169017 Reported-by: JianHong Yin <jiyin@redhat.com> Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-01-17Merge tag 'nfsd-6.2-4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux Pull nfsd fixes from Chuck Lever: - Fix recently introduced use-after-free bugs * tag 'nfsd-6.2-4' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux: NFSD: replace delayed_work with work_struct for nfsd_client_shrinker NFSD: register/unregister of nfsd-client shrinker at nfsd startup/shutdown time NFSD: fix use-after-free in nfsd4_ssc_setup_dul()
2023-01-12NFSD: replace delayed_work with work_struct for nfsd_client_shrinkerDai Ngo
Since nfsd4_state_shrinker_count always calls mod_delayed_work with 0 delay, we can replace delayed_work with work_struct to save some space and overhead. Also add the call to cancel_work after unregister the shrinker in nfs4_state_shutdown_net. Signed-off-by: Dai Ngo <dai.ngo@oracle.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-01-11NFSD: register/unregister of nfsd-client shrinker at nfsd startup/shutdown timeDai Ngo
Currently the nfsd-client shrinker is registered and unregistered at the time the nfsd module is loaded and unloaded. The problem with this is the shrinker is being registered before all of the relevant fields in nfsd_net are initialized when nfsd is started. This can lead to an oops when memory is low and the shrinker is called while nfsd is not running. This patch moves the register/unregister of nfsd-client shrinker from module load/unload time to nfsd startup/shutdown time. Fixes: 44df6f439a17 ("NFSD: add delegation reaper to react to low memory condition") Reported-by: Mike Galbraith <efault@gmx.de> Signed-off-by: Dai Ngo <dai.ngo@oracle.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-01-11fs: remove locks_inodeJeff Layton
locks_inode was turned into a wrapper around file_inode in de2a4a501e71 (Partially revert "locks: fix file locking on overlayfs"). Finish replacing locks_inode invocations everywhere with file_inode. Acked-by: Miklos Szeredi <mszeredi@redhat.com> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Reviewed-by: David Howells <dhowells@redhat.com> Signed-off-by: Jeff Layton <jlayton@kernel.org>
2023-01-10Merge tag 'nfsd-6.2-3' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux Pull nfsd fixes from Chuck Lever: - Fix a race when creating NFSv4 files - Revert the use of relaxed bitops * tag 'nfsd-6.2-3' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux: NFSD: Use set_bit(RQ_DROPME) Revert "SUNRPC: Use RMW bitops in single-threaded hot paths" nfsd: fix handling of cached open files in nfsd4_open codepath
2023-01-06nfsd: fix handling of cached open files in nfsd4_open codepathJeff Layton
Commit fb70bf124b05 ("NFSD: Instantiate a struct file when creating a regular NFSv4 file") added the ability to cache an open fd over a compound. There are a couple of problems with the way this currently works: It's racy, as a newly-created nfsd_file can end up with its PENDING bit cleared while the nf is hashed, and the nf_file pointer is still zeroed out. Other tasks can find it in this state and they expect to see a valid nf_file, and can oops if nf_file is NULL. Also, there is no guarantee that we'll end up creating a new nfsd_file if one is already in the hash. If an extant entry is in the hash with a valid nf_file, nfs4_get_vfs_file will clobber its nf_file pointer with the value of op_file and the old nf_file will leak. Fix both issues by making a new nfsd_file_acquirei_opened variant that takes an optional file pointer. If one is present when this is called, we'll take a new reference to it instead of trying to open the file. If the nfsd_file already has a valid nf_file, we'll just ignore the optional file and pass the nfsd_file back as-is. Also rework the tracepoints a bit to allow for an "opened" variant and don't try to avoid counting acquisitions in the case where we already have a cached open file. Fixes: fb70bf124b05 ("NFSD: Instantiate a struct file when creating a regular NFSv4 file") Cc: Trond Myklebust <trondmy@hammerspace.com> Reported-by: Stanislav Saner <ssaner@redhat.com> Reported-and-Tested-by: Ruben Vestergaard <rubenv@drcmr.dk> Reported-and-Tested-by: Torkil Svensgaard <torkil@drcmr.dk> Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-12-12Merge tag 'nfsd-6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linuxLinus Torvalds
Pull nfsd updates from Chuck Lever: "This release introduces support for the CB_RECALL_ANY operation. NFSD can send this operation to request that clients return any delegations they choose. The server uses this operation to handle low memory scenarios or indicate to a client when that client has reached the maximum number of delegations the server supports. The NFSv4.2 READ_PLUS operation has been simplified temporarily whilst support for sparse files in local filesystems and the VFS is improved. Two major data structure fixes appear in this release: - The nfs4_file hash table is replaced with a resizable hash table to reduce the latency of NFSv4 OPEN operations. - Reference counting in the NFSD filecache has been hardened against races. In furtherance of removing support for NFSv2 in a subsequent kernel release, a new Kconfig option enables server-side support for NFSv2 to be left out of a kernel build. MAINTAINERS has been updated to indicate that changes to fs/exportfs should go through the NFSD tree" * tag 'nfsd-6.2' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux: (49 commits) NFSD: Avoid clashing function prototypes SUNRPC: Fix crasher in unwrap_integ_data() SUNRPC: Make the svc_authenticate tracepoint conditional NFSD: Use only RQ_DROPME to signal the need to drop a reply SUNRPC: Clean up xdr_write_pages() SUNRPC: Don't leak netobj memory when gss_read_proxy_verf() fails NFSD: add CB_RECALL_ANY tracepoints NFSD: add delegation reaper to react to low memory condition NFSD: add support for sending CB_RECALL_ANY NFSD: refactoring courtesy_client_reaper to a generic low memory shrinker trace: Relocate event helper files NFSD: pass range end to vfs_fsync_range() instead of count lockd: fix file selection in nlmsvc_cancel_blocked lockd: ensure we use the correct file descriptor when unlocking lockd: set missing fl_flags field when retrieving args NFSD: Use struct_size() helper in alloc_session() nfsd: return error if nfs4_setacl fails lockd: set other missing fields when unlocking files NFSD: Add an nfsd_file_fsync tracepoint sunrpc: svc: Remove an unused static function svc_ungetu32() ...
2022-12-10NFSD: add CB_RECALL_ANY tracepointsDai Ngo
Add tracepoints to trace start and end of CB_RECALL_ANY operation. Signed-off-by: Dai Ngo <dai.ngo@oracle.com> [ cel: added show_rca_mask() macro ] Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-12-10NFSD: add delegation reaper to react to low memory conditionDai Ngo
The delegation reaper is called by nfsd memory shrinker's on the 'count' callback. It scans the client list and sends the courtesy CB_RECALL_ANY to the clients that hold delegations. To avoid flooding the clients with CB_RECALL_ANY requests, the delegation reaper sends only one CB_RECALL_ANY request to each client per 5 seconds. Signed-off-by: Dai Ngo <dai.ngo@oracle.com> [ cel: moved definition of RCA4_TYPE_MASK_RDATA_DLG ] Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-12-10NFSD: refactoring courtesy_client_reaper to a generic low memory shrinkerDai Ngo
Refactoring courtesy_client_reaper to generic low memory shrinker so it can be used for other purposes. Signed-off-by: Dai Ngo <dai.ngo@oracle.com> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-12-10NFSD: Use struct_size() helper in alloc_session()Xiu Jianfeng
Use struct_size() helper to simplify the code, no functional changes. Signed-off-by: Xiu Jianfeng <xiujianfeng@huawei.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-11-30nfsd: use locks_inode_context helperJeff Layton
nfsd currently doesn't access i_flctx safely everywhere. This requires a smp_load_acquire, as the pointer is set via cmpxchg (a release operation). Acked-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jeff Layton <jlayton@kernel.org>
2022-11-28NFSD: Use rhashtable for managing nfs4_file objectsChuck Lever
fh_match() is costly, especially when filehandles are large (as is the case for NFSv4). It needs to be used sparingly when searching data structures. Unfortunately, with common workloads, I see multiple thousands of objects stored in file_hashtbl[], which has just 256 buckets, making its bucket hash chains quite lengthy. Walking long hash chains with the state_lock held blocks other activity that needs that lock. Sizable hash chains are a common occurrance once the server has handed out some delegations, for example -- IIUC, each delegated file is held open on the server by an nfs4_file object. To help mitigate the cost of searching with fh_match(), replace the nfs4_file hash table with an rhashtable, which can dynamically resize its bucket array to minimize hash chain length. The result of this modification is an improvement in the latency of NFSv4 operations, and the reduction of nfsd CPU utilization due to eliminating the cost of multiple calls to fh_match() and reducing the CPU cache misses incurred while walking long hash chains in the nfs4_file hash table. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: NeilBrown <neilb@suse.de> Reviewed-by: Jeff Layton <jlayton@kernel.org>
2022-11-28NFSD: Refactor find_file()Chuck Lever
find_file() is now the only caller of find_file_locked(), so just fold these two together. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: NeilBrown <neilb@suse.de> Reviewed-by: Jeff Layton <jlayton@kernel.org>
2022-11-28NFSD: Clean up find_or_add_file()Chuck Lever
Remove the call to find_file_locked() in insert_nfs4_file(). Tracing shows that over 99% of these calls return NULL. Thus it is not worth the expense of the extra bucket list traversal. insert_file() already deals correctly with the case where the item is already in the hash bucket. Since nfsd4_file_hash_insert() is now just a wrapper around insert_file(), move the meat of insert_file() into nfsd4_file_hash_insert() and get rid of it. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: NeilBrown <neilb@suse.de>
2022-11-28NFSD: Add a nfsd4_file_hash_remove() helperChuck Lever
Refactor to relocate hash deletion operation to a helper function that is close to most other nfs4_file data structure operations. The "noinline" annotation will become useful in a moment when the hlist_del_rcu() is replaced with a more complex rhash remove operation. It also guarantees that hash remove operations can be traced with "-p function -l remove_nfs4_file_locked". This also simplifies the organization of forward declarations: the to-be-added rhashtable and its param structure will be defined /after/ put_nfs4_file(). Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: NeilBrown <neilb@suse.de> Reviewed-by: Jeff Layton <jlayton@kernel.org>
2022-11-28NFSD: Clean up nfsd4_init_file()Chuck Lever
Name this function more consistently. I'm going to use nfsd4_file_ and nfsd4_file_hash_ for these helpers. Change the @fh parameter to be const pointer for better type safety. Finally, move the hash insertion operation to the caller. This is typical for most other "init_object" type helpers, and it is where most of the other nfs4_file hash table operations are located. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: NeilBrown <neilb@suse.de> Reviewed-by: Jeff Layton <jlayton@kernel.org>
2022-11-28NFSD: Update file_hashtbl() helpersChuck Lever
Enable callers to use const pointers for type safety. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: NeilBrown <neilb@suse.de> Reviewed-by: Jeff Layton <jlayton@kernel.org>
2022-11-28NFSD: Trace delegation revocationsChuck Lever
Delegation revocation is an exceptional event that is not otherwise visible externally (eg, no network traffic is emitted). Generate a trace record when it occurs so that revocation can be observed or other activity can be triggered. Example: nfsd-1104 [005] 1912.002544: nfsd_stid_revoke: client 633c9343:4e82788d stateid 00000003:00000001 ref=2 type=DELEG Trace infrastructure is provided for subsequent additional tracing related to nfs4_stid activity. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Tested-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: Jeff Layton <jlayton@kernel.org>
2022-11-28NFSD: Trace stateids returned via DELEGRETURNChuck Lever
Handing out a delegation stateid is recorded with the nfsd_deleg_read tracepoint, but there isn't a matching tracepoint for recording when the stateid is returned. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Jeff Layton <jlayton@kernel.org>
2022-11-28NFSD: Revert "NFSD: NFSv4 CLOSE should release an nfsd_file immediately"Chuck Lever
This reverts commit 5e138c4a750dc140d881dab4a8804b094bbc08d2. That commit attempted to make files available to other users as soon as all NFSv4 clients were done with them, rather than waiting until the filecache LRU had garbage collected them. It gets the reference counting wrong, for one thing. But it also misses that DELEGRETURN should release a file in the same fashion. In fact, any nfsd_file_put() on an file held open by an NFSv4 client needs potentially to release the file immediately... Clear the way for implementing that idea. Signed-off-by: Chuck Lever <chuck.lever@oracle.com> Reviewed-by: Jeff Layton <jlayton@kernel.org> Reviewed-by: NeilBrown <neilb@suse.de>
2022-11-28nfsd: don't call nfsd_file_put from client states seqfile displayJeff Layton
We had a report of this: BUG: sleeping function called from invalid context at fs/nfsd/filecache.c:440 ...with a stack trace showing nfsd_file_put being called from nfs4_show_open. This code has always tried to call fput while holding a spinlock, but we recently changed this to use the filecache, and that started triggering the might_sleep() in nfsd_file_put. states_start takes and holds the cl_lock while iterating over the client's states, and we can't sleep with that held. Have the various nfs4_show_* functions instead hold the fi_lock instead of taking a nfsd_file reference. Fixes: 78599c42ae3c ("nfsd4: add file to display list of client's opens") Link: https://bugzilla.redhat.com/show_bug.cgi?id=2138357 Reported-by: Zhi Li <yieli@redhat.com> Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-11-11Merge tag 'nfsd-6.1-4' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux Pull nfsd fixes from Chuck Lever: - Fix an export leak - Fix a potential tracepoint crash * tag 'nfsd-6.1-4' of git://git.kernel.org/pub/scm/linux/kernel/git/cel/linux: nfsd: put the export reference in nfsd4_verify_deleg_dentry nfsd: fix use-after-free in nfsd_file_do_acquire tracepoint
2022-11-08nfsd: put the export reference in nfsd4_verify_deleg_dentryJeff Layton
nfsd_lookup_dentry returns an export reference in addition to the dentry ref. Ensure that we put it too. Link: https://bugzilla.redhat.com/show_bug.cgi?id=2138866 Fixes: 876c553cb410 ("NFSD: verify the opened dentry after setting a delegation") Reported-by: Yongcheng Yang <yoyang@redhat.com> Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-10-11treewide: use get_random_u32() when possibleJason A. Donenfeld
The prandom_u32() function has been a deprecated inline wrapper around get_random_u32() for several releases now, and compiles down to the exact same code. Replace the deprecated wrapper with a direct call to the real function. The same also applies to get_random_int(), which is just a wrapper around get_random_u32(). This was done as a basic find and replace. Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Reviewed-by: Kees Cook <keescook@chromium.org> Reviewed-by: Yury Norov <yury.norov@gmail.com> Reviewed-by: Jan Kara <jack@suse.cz> # for ext4 Acked-by: Toke Høiland-Jørgensen <toke@toke.dk> # for sch_cake Acked-by: Chuck Lever <chuck.lever@oracle.com> # for nfsd Acked-by: Jakub Kicinski <kuba@kernel.org> Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> # for thunderbolt Acked-by: Darrick J. Wong <djwong@kernel.org> # for xfs Acked-by: Helge Deller <deller@gmx.de> # for parisc Acked-by: Heiko Carstens <hca@linux.ibm.com> # for s390 Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-09-26nfsd: extra checks when freeing delegation stateidsJeff Layton
We've had some reports of problems in the refcounting for delegation stateids that we've yet to track down. Add some extra checks to ensure that we've removed the object from various lists before freeing it. Link: https://bugzilla.redhat.com/show_bug.cgi?id=2127067 Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-09-26nfsd: make nfsd4_run_cb a bool return functionJeff Layton
queue_work can return false and not queue anything, if the work is already queued. If that happens in the case of a CB_RECALL, we'll have taken an extra reference to the stid that will never be put. Ensure we throw a warning in that case. Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-09-26nfsd: fix comments about spinlock handling with delegationsJeff Layton
Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-09-26nfsd: only fill out return pointer on success in nfsd4_lookup_stateidJeff Layton
In the case of a revoked delegation, we still fill out the pointer even when returning an error, which is bad form. Only overwrite the pointer on success. Signed-off-by: Jeff Layton <jlayton@kernel.org> Signed-off-by: Chuck Lever <chuck.lever@oracle.com>