[ Upstream commit 10396f4df8 ]
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: 44df6f439a ("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>
[ Upstream commit 9388a2aa45 ]
I'm working on restructuring the __string* macros so that it doesn't need
to recalculate the string twice. That is, it will save it off when
processing __string() and the __assign_str() will not need to do the work
again as it currently does.
Currently __string_len(item, src, len) doesn't actually use "src", but my
changes will require src to be correct as that is where the __assign_str()
will get its value from.
The event class nfsd_clid_class has:
__string_len(name, name, clp->cl_name.len)
But the second "name" does not exist and causes my changes to fail to
build. That second parameter should be: clp->cl_name.data.
Link: https://lore.kernel.org/linux-trace-kernel/20240222122828.3d8d213c@gandalf.local.home
Cc: Neil Brown <neilb@suse.de>
Cc: Olga Kornievskaia <kolga@netapp.com>
Cc: Dai Ngo <Dai.Ngo@oracle.com>
Cc: Tom Talpey <tom@talpey.com>
Cc: stable@vger.kernel.org
Fixes: d27b74a867 ("NFSD: Use new __string_len C macros for nfsd_clid_class")
Acked-by: Chuck Lever <chuck.lever@oracle.com>
Acked-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
In nfsd4_encode_fattr(), TIME_CREATE was being written out after all
other times. However, they should be written out in an order that
matches the bit flags in bmval1, which in this case are
#define FATTR4_WORD1_TIME_ACCESS (1UL << 15)
#define FATTR4_WORD1_TIME_CREATE (1UL << 18)
#define FATTR4_WORD1_TIME_DELTA (1UL << 19)
#define FATTR4_WORD1_TIME_METADATA (1UL << 20)
#define FATTR4_WORD1_TIME_MODIFY (1UL << 21)
so TIME_CREATE should come second.
I noticed this on a FreeBSD NFSv4.2 client, which supports creation
times. On this client, file times were weirdly permuted. With this
patch applied on the server, times looked normal on the client.
Fixes: e377a3e698 ("nfsd: Add support for the birth time attribute")
Link: https://unix.stackexchange.com/q/749605/56202
Signed-off-by: Tavian Barnes <tavianator@tavianator.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 147abcacee ]
The following request sequence to the same file causes the NFS client and
server getting into an infinite loop with COMMIT and NFS4ERR_DELAY:
OPEN
REMOVE
WRITE
COMMIT
Problem reported by recall11, recall12, recall14, recall20, recall22,
recall40, recall42, recall48, recall50 of nfstest suite.
This patch restores the handling of race condition in nfsd_file_do_acquire
with unlink to that prior of the regression.
Fixes: ac3a2585f0 ("nfsd: rework refcounting in filecache")
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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit 92e4a6733f ]
When queueing a dispose list to the appropriate "freeme" lists, it
pointlessly queues the objects one at a time to an intermediate list.
Remove a few helpers and just open code a list_move to make it more
clear and efficient. Better document the resulting functions with
kerneldoc comments.
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>
[ Upstream commit c4c649ab41 ]
While we were converting the nfs4_file hashtable to use the kernel's
resizable hashtable data structure, Neil Brown observed that the
list variant (rhltable) would be better for managing nfsd_file items
as well. The nfsd_file hash table will contain multiple entries for
the same inode -- these should be kept together on a list. And, it
could be possible for exotic or malicious client behavior to cause
the hash table to resize itself on every insertion.
A nice simplification is that rhltable_lookup() can return a list
that contains only nfsd_file items that match a given inode, which
enables us to eliminate specialized hash table helper functions and
use the default functions provided by the rhashtable implementation).
Since we are now storing nfsd_file items for the same inode on a
single list, that effectively reduces the number of hash entries
that have to be tracked in the hash table. The mininum bucket count
is therefore lowered.
Light testing with fstests generic/531 show no regressions.
Suggested-by: Neil Brown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit dcb779fcd4 ]
On most filesystems, there is no reason to delay reaping an nfsd_file
just because its underlying inode is still under writeback. nfsd just
relies on client activity or the local flusher threads to do writeback.
The main exception is NFS, which flushes all of its dirty data on last
close. Add a new EXPORT_OP_FLUSH_ON_CLOSE flag to allow filesystems to
signal that they do this, and only skip closing files under writeback on
such filesystems.
Also, remove a redundant NULL file pointer check in
nfsd_file_check_writeback, and clean up nfs's export op flag
definitions.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Acked-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
[ cel: adjusted to apply to v6.1.y ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[ Upstream commit b2ff1bd71d ]
The last thing that filp_close does is an fput, so don't bother taking
and putting the extra reference.
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>
[ Upstream commit b680cb9b73 ]
David Howells mentioned that he found this bit of code confusing, so
sprinkle in some comments to clarify.
Reported-by: David Howells <dhowells@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>
[ Upstream commit c6593366c0 ]
An error from break_lease is non-fatal, so we needn't destroy the
nfsd_file in that case. Just put the reference like we normally would
and return the error.
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>
[ Upstream commit d69b8dbfd0 ]
test_bit returns bool, so we can just compare the result of that to the
key->gc value without the "!!".
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>
[ Upstream commit 6c31e4c988 ]
Since v4 files are expected to be long-lived, there's little value in
closing them out of the cache when there is conflicting access.
Change the comparator to also match the gc value in the key. Change both
of the current users of that key to set the gc value in the key to
"true".
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>
[ Upstream commit 4102db175b ]
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: d47b295e8d ("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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 7c24fa2250 ]
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit f385f7d244 ]
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: 44df6f439a ("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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 5304930dba ]
The premise that "Once an svc thread is scheduled and executing an
RPC, no other processes will touch svc_rqst::rq_flags" is false.
svc_xprt_enqueue() examines the RQ_BUSY flag in scheduled nfsd
threads when determining which thread to wake up next.
Fixes: 9315564747 ("NFSD: Use only RQ_DROPME to signal the need to drop a reply")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit e78e274eb2 ]
When built with Control Flow Integrity, function prototypes between
caller and function declaration must match. These mismatches are visible
at compile time with the new -Wcast-function-type-strict in Clang[1].
There were 97 warnings produced by NFS. For example:
fs/nfsd/nfs4xdr.c:2228:17: warning: cast from '__be32 (*)(struct nfsd4_compoundargs *, struct nfsd4_access *)' (aka 'unsigned int (*)(struct nfsd4_compoundargs *, struct nfsd4_access *)') to 'nfsd4_dec' (aka 'unsigned int (*)(struct nfsd4_compoundargs *, void *)') converts to incompatible function type [-Wcast-function-type-strict]
[OP_ACCESS] = (nfsd4_dec)nfsd4_decode_access,
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The enc/dec callbacks were defined as passing "void *" as the second
argument, but were being implicitly cast to a new type. Replace the
argument with union nfsd4_op_u, and perform explicit member selection
in the function body. There are no resulting binary differences.
Changes were made mechanically using the following Coccinelle script,
with minor by-hand fixes for members that didn't already match their
existing argument name:
@find@
identifier func;
type T, opsT;
identifier ops, N;
@@
opsT ops[] = {
[N] = (T) func,
};
@already_void@
identifier find.func;
identifier name;
@@
func(...,
-void
+union nfsd4_op_u
*name)
{
...
}
@proto depends on !already_void@
identifier find.func;
type T;
identifier name;
position p;
@@
func@p(...,
T name
) {
...
}
@script:python get_member@
type_name << proto.T;
member;
@@
coccinelle.member = cocci.make_ident(type_name.split("_", 1)[1].split(' ',1)[0])
@convert@
identifier find.func;
type proto.T;
identifier proto.name;
position proto.p;
identifier get_member.member;
@@
func@p(...,
- T name
+ union nfsd4_op_u *u
) {
+ T name = &u->member;
...
}
@cast@
identifier find.func;
type T, opsT;
identifier ops, N;
@@
opsT ops[] = {
[N] =
- (T)
func,
};
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: Gustavo A. R. Silva <gustavoars@kernel.org>
Cc: linux-nfs@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 9315564747 ]
Clean up: NFSv2 has the only two usages of rpc_drop_reply in the
NFSD code base. Since NFSv2 is going away at some point, replace
these in order to simplify the "drop this reply?" check in
nfsd_dispatch().
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 44df6f439a ]
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 3959066b69 ]
Add XDR encode and decode function for CB_RECALL_ANY.
Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit a1049eb47f ]
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 22ae4c114f ]
We don't really care whether there are hashed entries when it comes to
scheduling the laundrette. They might all be non-gc entries, after all.
We only want to schedule it if there are entries on the LRU.
Switch to using list_lru_count, and move the check into
nfsd_file_gc_worker. The other callsite in nfsd_file_put doesn't need to
count entries, since it only schedules the laundrette after adding an
entry to the LRU.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 77c67530e1 ]
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>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit d47b295e8d ]
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>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 1542474800 ]
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>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 9270fc514b ]
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>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 3341678f2f ]
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>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 81a21fa3e7 ]
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>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 3fe828cadd ]
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>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit b48f8056c0 ]
Enable callers to use const pointers where they are able to.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit a1c74569bb ]
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 20eee313ff ]
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>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit b3276c1f5b ]
Record what we've learned recently about the NFSD filecache in a
documenting comment so our future selves don't forget what all this
is for.
Signed-off-by: Chuck Lever <chuck.lever@oracle.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>
[ Upstream commit 2f3a4b2ac2 ]
rpc.nfsd stopped supporting NFSv2 a year ago. Take the next logical
step toward deprecating it and allow NFSv2 support to be compiled out.
Add a new CONFIG_NFSD_V2 option that can be turned off and rework the
CONFIG_NFSD_V?_ACL option dependencies. Add a description that
discourages enabling it.
Also, change the description of CONFIG_NFSD to state that the always-on
version is now 3 instead of 2.
Finally, add an #ifdef around "case 2:" in __write_versions. When NFSv2
is disabled at compile time, this should make the kernel ignore attempts
to disable it at runtime, but still error out when trying to enable it.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Tom Talpey <tom@talpey.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit cb12fae1c3 ]
nfserrno() is common to all nfs versions, but nfsproc.c is specifically
for NFSv2. Move it to vfs.c, and the prototype to vfs.h.
While we're in here, remove the #ifdef EDQUOT check in this function.
It's apparently a holdover from the initial merge of the nfsd code in
1997. No other place in the kernel checks that that symbol is defined
before using it, so I think we can dispense with it here.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 8e823bafff ]
The kernel currently errors out if you attempt to enable or disable a
version that it doesn't recognize. Change it to ignore attempts to
disable an unrecognized version. If we don't support it, then there is
no harm in doing so.
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Tom Talpey <tom@talpey.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 69eed23baf ]
Variable host_err is assigned a value that is never read, it is being
re-assigned a value in every different execution path in the following
switch statement. The assignment is redundant and can be removed.
Cleans up clang-scan warning:
warning: Value stored to 'host_err' is never read [deadcode.DeadStores]
Signed-off-by: Colin Ian King <colin.i.king@gmail.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>
[ Upstream commit eeadcb7579 ]
Chuck had suggested reverting READ_PLUS so it returns a single DATA
segment covering the requested read range. This prepares the server for
a future "sparse read" function so support can easily be added without
needing to rip out the old READ_PLUS code at the same time.
Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
[ Upstream commit 5ea9a7c5fe ]
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: edcf972515 ("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>
[ Upstream commit edcf972515 ]
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: ce3c4ad7f4 ("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>
This reverts commit 03d68ffc48 which is
commit 9f28a971ee upstream.
It is reported to cause issues, so revert it.
Reported-by: email200202 <email200202@yahoo.com>
Link: https://lore.kernel.org/r/e341cb408b5663d8c91b8fa57b41bb984be43448.camel@kernel.org
Cc: NeilBrown <neilb@suse.de>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This reverts commit bb4f791cb2 which is
commit 2a501f55cd upstream.
It is reported to cause issues, so revert it.
Reported-by: email200202 <email200202@yahoo.com>
Link: https://lore.kernel.org/r/e341cb408b5663d8c91b8fa57b41bb984be43448.camel@kernel.org
Cc: NeilBrown <neilb@suse.de>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Jeff Layton