Commit graph

626 commits

Author SHA1 Message Date
Jeff Layton
cee9958b56 nfsd: extra checks when freeing delegation stateids
[ Upstream commit 895ddf5ed4c54ea9e3533606d7a8b4e4f27f95ef ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:24 +01:00
Jeff Layton
e449198bdf nfsd: make nfsd4_run_cb a bool return function
[ Upstream commit b95239ca4954a0d48b19c09ce7e8f31b453b4216 ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:24 +01:00
Jeff Layton
97136d46f3 nfsd: fix comments about spinlock handling with delegations
[ Upstream commit 25fbe1fca14142beae6c882f7906510363d42bff ]

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>
2024-11-19 12:28:24 +01:00
Jeff Layton
3ebcecc70b nfsd: only fill out return pointer on success in nfsd4_lookup_stateid
[ Upstream commit 4d01416ab41540bb13ec4a39ac4e6c4aa5934bc9 ]

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:24 +01:00
Chuck Lever
49512f390c NFSD: Cap rsize_bop result based on send buffer size
[ Upstream commit 76ce4dcec0dc08a032db916841ddc4e3998be317 ]

Since before the git era, NFSD has conserved the number of pages
held by each nfsd thread by combining the RPC receive and send
buffers into a single array of pages. This works because there are
no cases where an operation needs a large RPC Call message and a
large RPC Reply at the same time.

Once an RPC Call has been received, svc_process() updates
svc_rqst::rq_res to describe the part of rq_pages that can be
used for constructing the Reply. This means that the send buffer
(rq_res) shrinks when the received RPC record containing the RPC
Call is large.

Add an NFSv4 helper that computes the size of the send buffer. It
replaces svc_max_payload() in spots where svc_max_payload() returns
a value that might be larger than the remaining send buffer space.
Callers who need to know the transport's actual maximum payload size
will continue to use svc_max_payload().

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:24 +01:00
Chuck Lever
1f2e1bc5f1 NFSD: Rename the fields in copy_stateid_t
[ Upstream commit 781fde1a2ba2391f31142f46f964cf1148ca1791 ]

Code maintenance: The name of the copy_stateid_t::sc_count field
collides with the sc_count field in struct nfs4_stid, making the
latter difficult to grep for when auditing stateid reference
counting.

No behavior change expected.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:24 +01:00
ChenXiaoSong
dd6e1f79a4 nfsd: use DEFINE_SHOW_ATTRIBUTE to define nfsd_file_cache_stats_fops
[ Upstream commit 1342f9dd3fc219089deeb2620f6790f19b4129b1 ]

Use DEFINE_SHOW_ATTRIBUTE helper macro to simplify the code.

Signed-off-by: ChenXiaoSong <chenxiaosong2@huawei.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:24 +01:00
ChenXiaoSong
9281c30c7b nfsd: use DEFINE_SHOW_ATTRIBUTE to define nfsd_reply_cache_stats_fops
[ Upstream commit 64776611a06322b99386f8dfe3b3ba1aa0347a38 ]

Use DEFINE_SHOW_ATTRIBUTE helper macro to simplify the code.

nfsd_net is converted from seq_file->file instead of seq_file->private in
nfsd_reply_cache_stats_show().

Signed-off-by: ChenXiaoSong <chenxiaosong2@huawei.com>
[ cel: reduce line length ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:24 +01:00
ChenXiaoSong
e238dc11a8 nfsd: use DEFINE_SHOW_ATTRIBUTE to define client_info_fops
[ Upstream commit 1d7f6b302b75ff7acb9eb3cab0c631b10cfa7542 ]

Use DEFINE_SHOW_ATTRIBUTE helper macro to simplify the code.

inode is converted from seq_file->file instead of seq_file->private in
client_info_show().

Signed-off-by: ChenXiaoSong <chenxiaosong2@huawei.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:24 +01:00
ChenXiaoSong
f59427520b nfsd: use DEFINE_SHOW_ATTRIBUTE to define export_features_fops and supported_enctypes_fops
[ Upstream commit 9beeaab8e05d353d709103cafa1941714b4d5d94 ]

Use DEFINE_SHOW_ATTRIBUTE helper macro to simplify the code.

Signed-off-by: ChenXiaoSong <chenxiaosong2@huawei.com>
[ cel: reduce line length ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:24 +01:00
ChenXiaoSong
0e8c37ea28 nfsd: use DEFINE_PROC_SHOW_ATTRIBUTE to define nfsd_proc_ops
[ Upstream commit 0cfb0c4228a5c8e2ed2b58f8309b660b187cef02 ]

Use DEFINE_PROC_SHOW_ATTRIBUTE helper macro to simplify the code.

Signed-off-by: ChenXiaoSong <chenxiaosong2@huawei.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:24 +01:00
Chuck Lever
d437b8382a NFSD: Pack struct nfsd4_compoundres
[ Upstream commit 9f553e61bd36c1048543ac2f6945103dd2f742be ]

Remove a couple of 4-byte holes on platforms with 64-bit pointers.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:23 +01:00
Chuck Lever
7679d5f949 NFSD: Remove unused nfsd4_compoundargs::cachetype field
[ Upstream commit 77e378cf2a595d8e39cddf28a31efe6afd9394a0 ]

This field was added by commit 1091006c5eb1 ("nfsd: turn on reply
cache for NFSv4") but was never put to use.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:23 +01:00
Chuck Lever
b9f25e7749 NFSD: Remove "inline" directives on op_rsize_bop helpers
[ Upstream commit 6604148cf961b57fc735e4204f8996536da9253c ]

These helpers are always invoked indirectly, so the compiler can't
inline these anyway. While we're updating the synopses of these
helpers, defensively convert their parameters to const pointers.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:23 +01:00
Chuck Lever
ad36491e05 NFSD: Clean up nfs4svc_encode_compoundres()
[ Upstream commit 9993a66317fc9951322483a9edbfae95a640b210 ]

In today's Linux NFS server implementation, the NFS dispatcher
initializes each XDR result stream, and the NFSv4 .pc_func and
.pc_encode methods all use xdr_stream-based encoding. This keeps
rq_res.len automatically updated. There is no longer a need for
the WARN_ON_ONCE() check in nfs4svc_encode_compoundres().

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:23 +01:00
Chuck Lever
8e9e8ab202 NFSD: Clean up WRITE arg decoders
[ Upstream commit d4da5baa533215b14625458e645056baf646bb2e ]

xdr_stream_subsegment() already returns a boolean value.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:23 +01:00
Chuck Lever
8e65b00166 NFSD: Use xdr_inline_decode() to decode NFSv3 symlinks
[ Upstream commit c3d2a04f05c590303c125a176e6e43df4a436fdb ]

Replace the check for buffer over/underflow with a helper that is
commonly used for this purpose. The helper also sets xdr->nwords
correctly after successfully linearizing the symlink argument into
the stream's scratch buffer.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:23 +01:00
Chuck Lever
f6d3097d21 NFSD: Refactor common code out of dirlist helpers
[ Upstream commit 98124f5bd6c76699d514fbe491dd95265369cc99 ]

The dust has settled a bit and it's become obvious what code is
totally common between nfsd_init_dirlist_pages() and
nfsd3_init_dirlist_pages(). Move that common code to SUNRPC.

The new helper brackets the existing xdr_init_decode_pages() API.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:23 +01:00
Chuck Lever
1b7f6bc7bb NFSD: Reduce amount of struct nfsd4_compoundargs that needs clearing
[ Upstream commit 3fdc546462348b8a497c72bc894e0cde9f10fc40 ]

Have SunRPC clear everything except for the iops array. Then have
each NFSv4 XDR decoder clear it's own argument before decoding.

Now individual operations may have a large argument struct while not
penalizing the vast majority of operations with a small struct.

And, clearing the argument structure occurs as the argument fields
are initialized, enabling the CPU to do write combining on that
memory. In some cases, clearing is not even necessary because all
of the fields in the argument structure are initialized by the
decoder.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:23 +01:00
Chuck Lever
f98b7203d3 SUNRPC: Parametrize how much of argsize should be zeroed
[ Upstream commit 103cc1fafee48adb91fca0e19deb869fd23e46ab ]

Currently, SUNRPC clears the whole of .pc_argsize before processing
each incoming RPC transaction. Add an extra parameter to struct
svc_procedure to enable upper layers to reduce the amount of each
operation's argument structure that is zeroed by SUNRPC.

The size of struct nfsd4_compoundargs, in particular, is a lot to
clear on each incoming RPC Call. A subsequent patch will cut this
down to something closer to what NFSv2 and NFSv3 uses.

This patch should cause no behavior changes.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:23 +01:00
Dai Ngo
69510ff32c NFSD: add shrinker to reap courtesy clients on low memory condition
[ Upstream commit 7746b32f467b3813fb61faaab3258de35806a7ac ]

Add courtesy_client_reaper to react to low memory condition triggered
by the system memory shrinker.

The delayed_work for the courtesy_client_reaper is scheduled on
the shrinker's count callback using the laundry_wq.

The shrinker's scan callback is not used for expiring the courtesy
clients due to potential deadlocks.

Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
[ cel: adjusted to apply without e33c267ab70d ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:23 +01:00
Dai Ngo
6a3b8b1a29 NFSD: keep track of the number of courtesy clients in the system
[ Upstream commit 3a4ea23d86a317c4b68b9a69d51f7e84e1e04357 ]

Add counter nfs4_courtesy_client_count to nfsd_net to keep track
of the number of courtesy clients in the system.

Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:23 +01:00
Chuck Lever
9f62fbb137 NFSD: Make nfsd4_remove() wait before returning NFS4ERR_DELAY
[ Upstream commit 5f5f8b6d655fd947e899b1771c2f7cb581a06764 ]

nfsd_unlink() can kick off a CB_RECALL (via
vfs_unlink() -> leases_conflict()) if a delegation is present.
Before returning NFS4ERR_DELAY, give the client holding that
delegation a chance to return it and then retry the nfsd_unlink()
again, once.

Link: https://bugzilla.linux-nfs.org/show_bug.cgi?id=354
Tested-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
[ cel: backported to 5.10.y, prior to idmapped mounts ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:22 +01:00
Chuck Lever
83968fd144 NFSD: Make nfsd4_rename() wait before returning NFS4ERR_DELAY
[ Upstream commit 68c522afd0b1936b48a03a4c8b81261e7597c62d ]

nfsd_rename() can kick off a CB_RECALL (via
vfs_rename() -> leases_conflict()) if a delegation is present.
Before returning NFS4ERR_DELAY, give the client holding that
delegation a chance to return it and then retry the nfsd_rename()
again, once.

This version of the patch handles renaming an existing file,
but does not deal with renaming onto an existing file. That
case will still always trigger an NFS4ERR_DELAY.

Link: https://bugzilla.linux-nfs.org/show_bug.cgi?id=354
Tested-by: Igor Mammedov <imammedo@redhat.com>
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: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:22 +01:00
Chuck Lever
247f336ab3 NFSD: Make nfsd4_setattr() wait before returning NFS4ERR_DELAY
[ Upstream commit 34b91dda7124fc3259e4b2ae53e0c933dedfec01 ]

nfsd_setattr() can kick off a CB_RECALL (via
notify_change() -> break_lease()) if a delegation is present. Before
returning NFS4ERR_DELAY, give the client holding that delegation a
chance to return it and then retry the nfsd_setattr() again, once.

Link: https://bugzilla.linux-nfs.org/show_bug.cgi?id=354
Tested-by: Igor Mammedov <imammedo@redhat.com>
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: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:22 +01:00
Chuck Lever
f6546852a6 NFSD: Refactor nfsd_setattr()
[ Upstream commit c0aa1913db57219e91a0a8832363cbafb3a9cf8f ]

Move code that will be retried (in a subsequent patch) into a helper
function.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
[ cel: backported to 5.10.y, prior to idmapped mounts ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:22 +01:00
Chuck Lever
e54d48549d NFSD: Add a mechanism to wait for a DELEGRETURN
[ Upstream commit c035362eb935fe9381d9d1cc453bc2a37460e24c ]

Subsequent patches will use this mechanism to wake up an operation
that is waiting for a client to return a delegation.

The new tracepoint records whether the wait timed out or was
properly awoken by the expected DELEGRETURN:

            nfsd-1155  [002] 83799.493199: nfsd_delegret_wakeup: xid=0x14b7d6ef fh_hash=0xf6826792 (timed out)

Suggested-by: Jeff Layton <jlayton@kernel.org>
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: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:22 +01:00
Chuck Lever
b7367d586d NFSD: Add tracepoints to report NFSv4 callback completions
[ Upstream commit 1035d65446a018ca2dd179e29a2fcd6d29057781 ]

Wireshark has always been lousy about dissecting NFSv4 callbacks,
especially NFSv4.0 backchannel requests. Add tracepoints so we
can surgically capture these events in the trace log.

Tracepoints are time-stamped and ordered so that we can now observe
the timing relationship between a CB_RECALL Reply and the client's
DELEGRETURN Call. Example:

            nfsd-1153  [002]   211.986391: nfsd_cb_recall:       addr=192.168.1.67:45767 client 62ea82e4:fee7492a stateid 00000003:00000001

            nfsd-1153  [002]   212.095634: nfsd_compound:        xid=0x0000002c opcnt=2
            nfsd-1153  [002]   212.095647: nfsd_compound_status: op=1/2 OP_PUTFH status=0
            nfsd-1153  [002]   212.095658: nfsd_file_put:        hash=0xf72 inode=0xffff9291148c7410 ref=3 flags=HASHED|REFERENCED may=READ file=0xffff929103b3ea00
            nfsd-1153  [002]   212.095661: nfsd_compound_status: op=2/2 OP_DELEGRETURN status=0
   kworker/u25:8-148   [002]   212.096713: nfsd_cb_recall_done:  client 62ea82e4:fee7492a stateid 00000003:00000001 status=0

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: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:22 +01:00
Gaosheng Cui
5ea6d5466c nfsd: remove nfsd4_prepare_cb_recall() declaration
[ Upstream commit 18224dc58d960c65446971930d0487fc72d00598 ]

nfsd4_prepare_cb_recall() has been removed since
commit 0162ac2b978e ("nfsd: introduce nfsd4_callback_ops"),
so remove it.

Signed-off-by: Gaosheng Cui <cuigaosheng1@huawei.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:22 +01:00
Jeff Layton
010163df19 nfsd: clean up mounted_on_fileid handling
[ Upstream commit 6106d9119b6599fa23dc556b429d887b4c2d9f62 ]

We only need the inode number for this, not a full rack of attributes.
Rename this function make it take a pointer to a u64 instead of
struct kstat, and change it to just request STATX_INO.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
[ cel: renamed get_mounted_on_ino() ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:22 +01:00
Chuck Lever
d5de26ae3e NFSD: Fix handling of oversized NFSv4 COMPOUND requests
[ Upstream commit 7518a3dc5ea249d4112156ce71b8b184eb786151 ]

If an NFS server returns NFS4ERR_RESOURCE on the first operation in
an NFSv4 COMPOUND, there's no way for a client to know where the
problem is and then simplify the compound to make forward progress.

So instead, make NFSD process as many operations in an oversized
COMPOUND as it can and then return NFS4ERR_RESOURCE on the first
operation it did not process.

pynfs NFSv4.0 COMP6 exercises this case, but checks only for the
COMPOUND status code, not whether the server has processed any
of the operations.

pynfs NFSv4.1 SEQ6 and SEQ7 exercise the NFSv4.1 case, which detects
too many operations per COMPOUND by checking against the limits
negotiated when the session was created.

Suggested-by: Bruce Fields <bfields@fieldses.org>
Fixes: 0078117c6d91 ("nfsd: return RESOURCE not GARBAGE_ARGS on too many ops")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:22 +01:00
NeilBrown
3568fa858e NFSD: drop fname and flen args from nfsd_create_locked()
[ Upstream commit 9558f9304ca1903090fa5d995a3269a8e82804b4 ]

nfsd_create_locked() does not use the "fname" and "flen" arguments, so
drop them from declaration and all callers.

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: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:22 +01:00
Chuck Lever
0fe5d64021 NFSD: Protect against send buffer overflow in NFSv3 READ
[ Upstream commit fa6be9cc6e80ec79892ddf08a8c10cabab9baf38 ]

Since before the git era, NFSD has conserved the number of pages
held by each nfsd thread by combining the RPC receive and send
buffers into a single array of pages. This works because there are
no cases where an operation needs a large RPC Call message and a
large RPC Reply at the same time.

Once an RPC Call has been received, svc_process() updates
svc_rqst::rq_res to describe the part of rq_pages that can be
used for constructing the Reply. This means that the send buffer
(rq_res) shrinks when the received RPC record containing the RPC
Call is large.

A client can force this shrinkage on TCP by sending a correctly-
formed RPC Call header contained in an RPC record that is
excessively large. The full maximum payload size cannot be
constructed in that case.

Cc: <stable@vger.kernel.org>
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: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:22 +01:00
Chuck Lever
c15bc8a9c4 NFSD: Protect against send buffer overflow in NFSv2 READ
[ Upstream commit 401bc1f90874280a80b93f23be33a0e7e2d1f912 ]

Since before the git era, NFSD has conserved the number of pages
held by each nfsd thread by combining the RPC receive and send
buffers into a single array of pages. This works because there are
no cases where an operation needs a large RPC Call message and a
large RPC Reply at the same time.

Once an RPC Call has been received, svc_process() updates
svc_rqst::rq_res to describe the part of rq_pages that can be
used for constructing the Reply. This means that the send buffer
(rq_res) shrinks when the received RPC record containing the RPC
Call is large.

A client can force this shrinkage on TCP by sending a correctly-
formed RPC Call header contained in an RPC record that is
excessively large. The full maximum payload size cannot be
constructed in that case.

Cc: <stable@vger.kernel.org>
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: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:21 +01:00
Chuck Lever
956015a28a NFSD: Protect against send buffer overflow in NFSv3 READDIR
[ Upstream commit 640f87c190e0d1b2a0fcb2ecf6d2cd53b1c41991 ]

Since before the git era, NFSD has conserved the number of pages
held by each nfsd thread by combining the RPC receive and send
buffers into a single array of pages. This works because there are
no cases where an operation needs a large RPC Call message and a
large RPC Reply message at the same time.

Once an RPC Call has been received, svc_process() updates
svc_rqst::rq_res to describe the part of rq_pages that can be
used for constructing the Reply. This means that the send buffer
(rq_res) shrinks when the received RPC record containing the RPC
Call is large.

A client can force this shrinkage on TCP by sending a correctly-
formed RPC Call header contained in an RPC record that is
excessively large. The full maximum payload size cannot be
constructed in that case.

Thanks to Aleksi Illikainen and Kari Hulkko for uncovering this
issue.

Reported-by: Ben Ronallo <Benjamin.Ronallo@synopsys.com>
Cc: <stable@vger.kernel.org>
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: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:21 +01:00
Chuck Lever
abcc21fbd6 NFSD: Protect against send buffer overflow in NFSv2 READDIR
[ Upstream commit 00b4492686e0497fdb924a9d4c8f6f99377e176c ]

Restore the previous limit on the @count argument to prevent a
buffer overflow attack.

Fixes: 53b1119a6e50 ("NFSD: Fix READDIR buffer overflow")
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: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:21 +01:00
Chuck Lever
9cbaef3ecb NFSD: Increase NFSD_MAX_OPS_PER_COMPOUND
[ Upstream commit 80e591ce636f3ae6855a0ca26963da1fdd6d4508 ]

When attempting an NFSv4 mount, a Solaris NFSv4 client builds a
single large COMPOUND that chains a series of LOOKUPs to get to the
pseudo filesystem root directory that is to be mounted. The Linux
NFS server's current maximum of 16 operations per NFSv4 COMPOUND is
not large enough to ensure that this works for paths that are more
than a few components deep.

Since NFSD_MAX_OPS_PER_COMPOUND is mostly a sanity check, and most
NFSv4 COMPOUNDS are between 3 and 6 operations (thus they do not
trigger any re-allocation of the operation array on the server),
increasing this maximum should result in little to no impact.

The ops array can get large now, so allocate it via vmalloc() to
help ensure memory fragmentation won't cause an allocation failure.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=216383
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:21 +01:00
Christophe JAILLET
99d370f0ed nfsd: Propagate some error code returned by memdup_user()
[ Upstream commit 30a30fcc3fc1ad4c5d017c9fcb75dc8f59e7bdad ]

Propagate the error code returned by memdup_user() instead of a hard coded
-EFAULT.

Suggested-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:21 +01:00
Christophe JAILLET
f3221f6ee2 nfsd: Avoid some useless tests
[ Upstream commit d44899b8bb0b919f923186c616a84f0e70e04772 ]

memdup_user() can't return NULL, so there is no point for checking for it.

Simplify some tests accordingly.

Suggested-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:21 +01:00
Jinpeng Cui
0af51701b1 NFSD: remove redundant variable status
[ Upstream commit 4ab3442ca384a02abf8b1f2b3449a6c547851873 ]

Return value directly from fh_verify() do_open_permission()
exp_pseudoroot() instead of getting value from
redundant variable status.

Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Jinpeng Cui <cui.jinpeng2@zte.com.cn>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:21 +01:00
Olga Kornievskaia
1304ec2084 NFSD enforce filehandle check for source file in COPY
[ Upstream commit 754035ff79a14886e68c0c9f6fa80adb21f12b53 ]

If the passed in filehandle for the source file in the COPY operation
is not a regular file, the server MUST return NFS4ERR_WRONG_TYPE.

Signed-off-by: Olga Kornievskaia <kolga@netapp.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
[ cel: adjusted to apply to v5.10.y ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:21 +01:00
Wolfram Sang
56409d62dc NFSD: move from strlcpy with unused retval to strscpy
[ Upstream commit 72f78ae00a8e5d7abe13abac8305a300f6afd74b ]

Follow the advice of the below link and prefer 'strscpy' in this
subsystem. Conversion is 1:1 because the return value is not used.
Generated by a coccinelle script.

Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/
Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:21 +01:00
Al Viro
bf60e51731 nfsd_splice_actor(): handle compound pages
[ Upstream commit bfbfb6182ad1d7d184b16f25165faad879147f79 ]

pipe_buffer might refer to a compound page (and contain more than a PAGE_SIZE
worth of data).  Theoretically it had been possible since way back, but
nfsd_splice_actor() hadn't run into that until copy_page_to_iter() change.
Fortunately, the only thing that changes for compound pages is that we
need to stuff each relevant subpage in and convert the offset into offset
in the first subpage.

Acked-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Benjamin Coddington <bcodding@redhat.com>
Fixes: f0f6b614f83d "copy_page_to_iter(): don't split high-order page in case of ITER_PIPE"
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
[ cel: "‘for’ loop initial declarations are only allowed in C99 or C11 mode" ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:21 +01:00
NeilBrown
a7f502860d NFSD: fix regression with setting ACLs.
[ Upstream commit 00801cd92d91e94aa04d687f9bb9a9104e7c3d46 ]

A recent patch moved ACL setting into nfsd_setattr().
Unfortunately it didn't work as nfsd_setattr() aborts early if
iap->ia_valid is 0.

Remove this test, and instead avoid calling notify_change() when
ia_valid is 0.

This means that nfsd_setattr() will now *always* lock the inode.
Previously it didn't if only a ATTR_MODE change was requested on a
symlink (see Commit 15b7a1b86d66 ("[PATCH] knfsd: fix setattr-on-symlink
error return")). I don't think this change really matters.

Fixes: c0cbe70742f4 ("NFSD: add posix ACLs to struct nfsd_attrs")
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
[ cel: backported to 5.10.y, prior to idmapped mounts ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:21 +01:00
NeilBrown
a81e7962f6 NFSD: use (un)lock_inode instead of fh_(un)lock for file operations
[ Upstream commit bb4d53d66e4b8c8b8e5634802262e53851a2d2db ]

When locking a file to access ACLs and xattrs etc, use explicit locking
with inode_lock() instead of fh_lock().  This means that the calls to
fh_fill_pre/post_attr() are also explicit which improves readability and
allows us to place them only where they are needed.  Only the xattr
calls need pre/post information.

When locking a file we don't need I_MUTEX_PARENT as the file is not a
parent of anything, so we can use inode_lock() directly rather than the
inode_lock_nested() call that fh_lock() uses.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: NeilBrown <neilb@suse.de>
[ cel: backported to 5.10.y, prior to idmapped mounts ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:04 +01:00
NeilBrown
574c240441 NFSD: use explicit lock/unlock for directory ops
[ Upstream commit debf16f0c671cb8db154a9ebcd6014cfff683b80 ]

When creating or unlinking a name in a directory use explicit
inode_lock_nested() instead of fh_lock(), and explicit calls to
fh_fill_pre_attrs() and fh_fill_post_attrs().  This is already done
for renames, with lock_rename() as the explicit locking.

Also move the 'fill' calls closer to the operation that might change the
attributes.  This way they are avoided on some error paths.

For the v2-only code in nfsproc.c, the fill calls are not replaced as
they aren't needed.

Making the locking explicit will simplify proposed future changes to
locking for directories.  It also makes it easily visible exactly where
pre/post attributes are used - not all callers of fh_lock() actually
need the pre/post attributes.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: NeilBrown <neilb@suse.de>
[ cel: backported to 5.10.y, prior to idmapped mounts ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:04 +01:00
NeilBrown
c5547a3fc7 NFSD: only call fh_unlock() once in nfsd_link()
[ Upstream commit e18bcb33bc5b69bccc2b532075aa00bb49cc01c5 ]

On non-error paths, nfsd_link() calls fh_unlock() twice.  This is safe
because fh_unlock() records that the unlock has been done and doesn't
repeat it.
However it makes the code a little confusing and interferes with changes
that are planned for directory locking.

So rearrange the code to ensure fh_unlock() is called exactly once if
fh_lock() was called.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:04 +01:00
NeilBrown
1c0a2ac5b9 NFSD: always drop directory lock in nfsd_unlink()
[ Upstream commit b677c0c63a135a916493c064906582e9f3ed4802 ]

Some error paths in nfsd_unlink() allow it to exit without unlocking the
directory.  This is not a problem in practice as the directory will be
locked with an fh_put(), but it is untidy and potentially confusing.

This allows us to remove all the fh_unlock() calls that are immediately
after nfsd_unlink() calls.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:04 +01:00
NeilBrown
8b67124316 NFSD: change nfsd_create()/nfsd_symlink() to unlock directory before returning.
[ Upstream commit 927bfc5600cd6333c9ef9f090f19e66b7d4c8ee1 ]

nfsd_create() usually returns with the directory still locked.
nfsd_symlink() usually returns with it unlocked.  This is clumsy.

Until recently nfsd_create() needed to keep the directory locked until
ACLs and security label had been set.  These are now set inside
nfsd_create() (in nfsd_setattr()) so this need is gone.

So change nfsd_create() and nfsd_symlink() to always unlock, and remove
any fh_unlock() calls that follow calls to these functions.

Signed-off-by: NeilBrown <neilb@suse.de>
[ cel: backported to 5.10.y, prior to idmapped mounts ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:04 +01:00
NeilBrown
21505959e5 NFSD: add posix ACLs to struct nfsd_attrs
[ Upstream commit c0cbe70742f4a70893cd6e5f6b10b6e89b6db95b ]

pacl and dpacl pointers are added to struct nfsd_attrs, which requires
that we have an nfsd_attrs_free() function to free them.
Those nfsv4 functions that can set ACLs now set up these pointers
based on the passed in NFSv4 ACL.

nfsd_setattr() sets the acls as appropriate.

Errors are handled as with security labels.

Signed-off-by: NeilBrown <neilb@suse.de>
[ cel: backported to 5.10.y, prior to idmapped mounts ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:04 +01:00
NeilBrown
6b797de75d NFSD: add security label to struct nfsd_attrs
[ Upstream commit d6a97d3f589a3a46a16183e03f3774daee251317 ]

nfsd_setattr() now sets a security label if provided, and nfsv4 provides
it in the 'open' and 'create' paths and the 'setattr' path.
If setting the label failed (including because the kernel doesn't
support labels), an error field in 'struct nfsd_attrs' is set, and the
caller can respond.  The open/create callers clear
FATTR4_WORD2_SECURITY_LABEL in the returned attr set in this case.
The setattr caller returns the error.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:04 +01:00
NeilBrown
e738779ebd NFSD: set attributes when creating symlinks
[ Upstream commit 93adc1e391a761441d783828b93979b38093d011 ]

The NFS protocol includes attributes when creating symlinks.
Linux does store attributes for symlinks and allows them to be set,
though they are not used for permission checking.

NFSD currently doesn't set standard (struct iattr) attributes when
creating symlinks, but for NFSv4 it does set ACLs and security labels.
This is inconsistent.

To improve consistency, pass the provided attributes into nfsd_symlink()
and call nfsd_create_setattr() to set them.

NOTE: this results in a behaviour change for all NFS versions when the
client sends non-default attributes with a SYMLINK request. With the
Linux client, the only attributes are:
	attr.ia_mode = S_IFLNK | S_IRWXUGO;
	attr.ia_valid = ATTR_MODE;
so the final outcome will be unchanged. Other clients might sent
different attributes, and if they did they probably expect them to be
honoured.

We ignore any error from nfsd_create_setattr().  It isn't really clear
what should be done if a file is successfully created, but the
attributes cannot be set.  NFS doesn't allow partial success to be
reported.  Reporting failure is probably more misleading than reporting
success, so the status is ignored.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:04 +01:00
NeilBrown
3b8c5ad99e NFSD: introduce struct nfsd_attrs
[ Upstream commit 7fe2a71dda349a1afa75781f0cc7975be9784d15 ]

The attributes that nfsd might want to set on a file include 'struct
iattr' as well as an ACL and security label.
The latter two are passed around quite separately from the first, in
part because they are only needed for NFSv4.  This leads to some
clumsiness in the code, such as the attributes NOT being set in
nfsd_create_setattr().

We need to keep the directory locked until all attributes are set to
ensure the file is never visibile without all its attributes.  This need
combined with the inconsistent handling of attributes leads to more
clumsiness.

As a first step towards tidying this up, introduce 'struct nfsd_attrs'.
This is passed (by reference) to vfs.c functions that work with
attributes, and is assembled by the various nfs*proc functions which
call them.  As yet only iattr is included, but future patches will
expand this.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:03 +01:00
Jeff Layton
8b69402310 NFSD: verify the opened dentry after setting a delegation
[ Upstream commit 876c553cb41026cb6ad3cef970a35e5f69c42a25 ]

Between opening a file and setting a delegation on it, someone could
rename or unlink the dentry. If this happens, we do not want to grant a
delegation on the open.

On a CLAIM_NULL open, we're opening by filename, and we may (in the
non-create case) or may not (in the create case) be holding i_rwsem
when attempting to set a delegation.  The latter case allows a
race.

After getting a lease, redo the lookup of the file being opened and
validate that the resulting dentry matches the one in the open file
description.

To properly redo the lookup we need an rqst pointer to pass to
nfsd_lookup_dentry(), so make sure that is available.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:03 +01:00
Jeff Layton
a6651c65bb NFSD: drop fh argument from alloc_init_deleg
[ Upstream commit bbf936edd543e7220f60f9cbd6933b916550396d ]

Currently, we pass the fh of the opened file down through several
functions so that alloc_init_deleg can pass it to delegation_blocked.
The filehandle of the open file is available in the nfs4_file however,
so there's no need to pass it in a separate argument.

Drop the argument from alloc_init_deleg, nfs4_open_delegation and
nfs4_set_delegation.

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>
2024-11-19 12:28:03 +01:00
Chuck Lever
a483435728 NFSD: Move copy offload callback arguments into a separate structure
[ Upstream commit a11ada99ce93a79393dc6683d22f7915748c8f6b ]

Refactor so that CB_OFFLOAD arguments can be passed without
allocating a whole struct nfsd4_copy object. On my system (x86_64)
this removes another 96 bytes from struct nfsd4_copy.

[ cel: adjusted to apply to v5.10.y ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:03 +01:00
Chuck Lever
fb3a5a8f17 NFSD: Add nfsd4_send_cb_offload()
[ Upstream commit e72f9bc006c08841c46d27747a4debc747a8fe13 ]

Refactor for legibility.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:03 +01:00
Chuck Lever
dd21bfb08b NFSD: Remove kmalloc from nfsd4_do_async_copy()
[ Upstream commit ad1e46c9b07b13659635ee5405f83ad0df143116 ]

Instead of manufacturing a phony struct nfsd_file, pass the
struct file returned by nfs42_ssc_open() directly to
nfsd4_do_copy().

[ cel: adjusted to apply to v5.10.y ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:03 +01:00
Chuck Lever
5cccd2a70a NFSD: Refactor nfsd4_do_copy()
[ Upstream commit 3b7bf5933cada732783554edf0dc61283551c6cf ]

Refactor: Now that nfsd4_do_copy() no longer calls the cleanup
helpers, plumb the use of struct file pointers all the way down to
_nfsd_copy_file_range().

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:03 +01:00
Chuck Lever
0faacbdb09 NFSD: Refactor nfsd4_cleanup_inter_ssc() (2/2)
[ Upstream commit 478ed7b10d875da2743d1a22822b9f8a82df8f12 ]

Move the nfsd4_cleanup_*() call sites out of nfsd4_do_copy(). A
subsequent patch will modify one of the new call sites to avoid
the need to manufacture the phony struct nfsd_file.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:03 +01:00
Chuck Lever
428836a908 NFSD: Refactor nfsd4_cleanup_inter_ssc() (1/2)
[ Upstream commit 24d796ea383b8a4c8234e06d1b14bbcd371192ea ]

The @src parameter is sometimes a pointer to a struct nfsd_file and
sometimes a pointer to struct file hiding in a phony struct
nfsd_file. Refactor nfsd4_cleanup_inter_ssc() so the @src parameter
is always an explicit struct file.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:03 +01:00
Chuck Lever
71edd77802 NFSD: Replace boolean fields in struct nfsd4_copy
[ Upstream commit 1913cdf56cb5bfbc8170873728d13598cbecda23 ]

Clean up: saves 8 bytes, and we can replace check_and_set_stop_copy()
with an atomic bitop.

[ cel: adjusted to apply to v5.10.y ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:03 +01:00
Chuck Lever
97b56f1995 NFSD: Make nfs4_put_copy() static
[ Upstream commit 8ea6e2c90bb0eb74a595a12e23a1dff9abbc760a ]

Clean up: All call sites are in fs/nfsd/nfs4proc.c.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:03 +01:00
Chuck Lever
47dc48b1b3 NFSD: Reorder the fields in struct nfsd4_op
[ Upstream commit d314309425ad5dc1b6facdb2d456580fb5fa5e3a ]

Pack the fields to reduce the size of struct nfsd4_op, which is used
an array in struct nfsd4_compoundargs.

sizeof(struct nfsd4_op):
Before: /* size: 672, cachelines: 11, members: 5 */
After:  /* size: 640, cachelines: 10, members: 5 */

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:03 +01:00
Chuck Lever
976e4c5d40 NFSD: Shrink size of struct nfsd4_copy
[ Upstream commit 87689df694916c40e8e6c179ab1c8710f65cb6c6 ]

struct nfsd4_copy is part of struct nfsd4_op, which resides in an
8-element array.

sizeof(struct nfsd4_op):
Before: /* size: 1696, cachelines: 27, members: 5 */
After:  /* size: 672, cachelines: 11, members: 5 */

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:03 +01:00
Chuck Lever
61c143ed41 NFSD: Shrink size of struct nfsd4_copy_notify
[ Upstream commit 09426ef2a64ee189ca1e3298f1e874842dbf35ea ]

struct nfsd4_copy_notify is part of struct nfsd4_op, which resides
in an 8-element array.

sizeof(struct nfsd4_op):
Before: /* size: 2208, cachelines: 35, members: 5 */
After:  /* size: 1696, cachelines: 27, members: 5 */

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:02 +01:00
Chuck Lever
82a8990f91 NFSD: nfserrno(-ENOMEM) is nfserr_jukebox
[ Upstream commit bb4d842722b84a2731257054b6405f2d866fc5f3 ]

Suggested-by: Dai Ngo <dai.ngo@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:02 +01:00
Chuck Lever
22ed210e34 NFSD: Fix strncpy() fortify warning
[ Upstream commit 5304877936c0a67e1a01464d113bae4c81eacdb6 ]

In function ‘strncpy’,
    inlined from ‘nfsd4_ssc_setup_dul’ at /home/cel/src/linux/manet/fs/nfsd/nfs4proc.c:1392:3,
    inlined from ‘nfsd4_interssc_connect’ at /home/cel/src/linux/manet/fs/nfsd/nfs4proc.c:1489:11:
/home/cel/src/linux/manet/include/linux/fortify-string.h:52:33: warning: ‘__builtin_strncpy’ specified bound 63 equals destination size [-Wstringop-truncation]
   52 | #define __underlying_strncpy    __builtin_strncpy
      |                                 ^
/home/cel/src/linux/manet/include/linux/fortify-string.h:89:16: note: in expansion of macro ‘__underlying_strncpy’
   89 |         return __underlying_strncpy(p, q, size);
      |                ^~~~~~~~~~~~~~~~~~~~

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:02 +01:00
Chuck Lever
7b1c5f6a61 NFSD: Clean up nfsd4_encode_readlink()
[ Upstream commit 99b002a1fa00d90e66357315757e7277447ce973 ]

Similar changes to nfsd4_encode_readv(), all bundled into a single
patch.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:02 +01:00
Chuck Lever
1684ec2426 NFSD: Use xdr_pad_size()
[ Upstream commit 5e64d85c7d0c59cfcd61d899720b8ccfe895d743 ]

Clean up: Use a helper instead of open-coding the calculation of
the XDR pad size.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:02 +01:00
Chuck Lever
31930f0bd1 NFSD: Simplify starting_len
[ Upstream commit 071ae99feadfc55979f89287d6ad2c6a315cb46d ]

Clean-up: Now that nfsd4_encode_readv() does not have to encode the
EOF or rd_length values, it no longer needs to subtract 8 from
@starting_len.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:02 +01:00
Chuck Lever
bb201cc062 NFSD: Optimize nfsd4_encode_readv()
[ Upstream commit 28d5bc468efe74b790e052f758ce083a5015c665 ]

write_bytes_to_xdr_buf() is pretty expensive to use for inserting
an XDR data item that is always 1 XDR_UNIT at an address that is
always XDR word-aligned.

Since both the readv and splice read paths encode EOF and maxcount
values, move both to a common code path.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:02 +01:00
Chuck Lever
11f94493ca NFSD: Add an nfsd4_read::rd_eof field
[ Upstream commit 24c7fb85498eda1d4c6b42cc4886328429814990 ]

Refactor: Make the EOF result available in the entire NFSv4 READ
path.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:02 +01:00
Chuck Lever
abc7f2871b NFSD: Clean up SPLICE_OK in nfsd4_encode_read()
[ Upstream commit c738b218a2e5a753a336b4b7fee6720b902c7ace ]

Do the test_bit() once -- this reduces the number of locked-bus
operations and makes the function a little easier to read.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:02 +01:00
Chuck Lever
b91534de99 NFSD: Optimize nfsd4_encode_fattr()
[ Upstream commit ab04de60ae1cc64ae16b77feae795311b97720c7 ]

write_bytes_to_xdr_buf() is a generic way to place a variable-length
data item in an already-reserved spot in the encoding buffer.

However, it is costly. In nfsd4_encode_fattr(), it is unnecessary
because the data item is fixed in size and the buffer destination
address is always word-aligned.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:02 +01:00
Chuck Lever
aa5514527c NFSD: Optimize nfsd4_encode_operation()
[ Upstream commit 095a764b7afb06c9499b798c04eaa3cbf70ebe2d ]

write_bytes_to_xdr_buf() is a generic way to place a variable-length
data item in an already-reserved spot in the encoding buffer.
However, it is costly, and here, it is unnecessary because the
data item is fixed in size, the buffer destination address is
always word-aligned, and the destination location is already in
@p.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:02 +01:00
Jeff Layton
aedaa70d28 nfsd: silence extraneous printk on nfsd.ko insertion
[ Upstream commit 3a5940bfa17fb9964bf9688b4356ca643a8f5e2d ]

This printk pops every time nfsd.ko gets plugged in. Most kmods don't do
that and this one is not very informative. Olaf's email address seems to
be defunct at this point anyway. Just drop it.

Cc: Olaf Kirch <okir@suse.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>
2024-11-19 12:28:02 +01:00
Dai Ngo
5e0ff4dbe3 NFSD: limit the number of v4 clients to 1024 per 1GB of system memory
[ Upstream commit 4271c2c0887562318a0afef97d32d8a71cbe0743 ]

Currently there is no limit on how many v4 clients are supported
by the system. This can be a problem in systems with small memory
configuration to function properly when a very large number of
clients exist that creates memory shortage conditions.

This patch enforces a limit of 1024 NFSv4 clients, including courtesy
clients, per 1GB of system memory.  When the number of the clients
reaches the limit, requests that create new clients are returned
with NFS4ERR_DELAY and the laundromat is kicked start to trim old
clients. Due to the overhead of the upcall to remove the client
record, the maximun number of clients the laundromat removes on
each run is limited to 128. This is done to ensure the laundromat
can still process the other tasks in a timely manner.

Since there is now a limit of the number of clients, the 24-hr
idle time limit of courtesy client is no longer needed and was
removed.

Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:02 +01:00
Dai Ngo
65c0a8306a NFSD: keep track of the number of v4 clients in the system
[ Upstream commit 0926c39515aa065a296e97dfc8790026f1e53f86 ]

Add counter nfs4_client_count to keep track of the total number
of v4 clients, including courtesy clients, in the system.

Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:02 +01:00
Dai Ngo
90f61df124 NFSD: refactoring v4 specific code to a helper in nfs4state.c
[ Upstream commit 6867137ebcf4155fe25f2ecf7c29b9fb90a76d1d ]

This patch moves the v4 specific code from nfsd_init_net() to
nfsd4_init_leases_net() helper in nfs4state.c

Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:01 +01:00
Chuck Lever
c035874cc9 NFSD: Ensure nf_inode is never dereferenced
[ Upstream commit 427f5f83a3191cbf024c5aea6e5b601cdf88d895 ]

The documenting comment for struct nf_file states:

/*
 * A representation of a file that has been opened by knfsd. These are hashed
 * in the hashtable by inode pointer value. Note that this object doesn't
 * hold a reference to the inode by itself, so the nf_inode pointer should
 * never be dereferenced, only used for comparison.
 */

Replace the two existing dereferences to make the comment always
true.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:01 +01:00
Chuck Lever
276969802c NFSD: NFSv4 CLOSE should release an nfsd_file immediately
[ Upstream commit 5e138c4a750dc140d881dab4a8804b094bbc08d2 ]

The last close of a file should enable other accessors to open and
use that file immediately. Leaving the file open in the filecache
prevents other users from accessing that file until the filecache
garbage-collects the file -- sometimes that takes several seconds.

Reported-by: Wang Yugui <wangyugui@e16-tech.com>
Link: https://bugzilla.linux-nfs.org/show_bug.cgi?387
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:01 +01:00
Chuck Lever
450cd975fe NFSD: Move nfsd_file_trace_alloc() tracepoint
[ Upstream commit b40a2839470cd62ed68c4a32d72a18ee8975b1ac ]

Avoid recording the allocation of an nfsd_file item that is
immediately released because a matching item was already
inserted in the hash.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:01 +01:00
Chuck Lever
96ab7b7d71 NFSD: Separate tracepoints for acquire and create
[ Upstream commit be0230069fcbf7d332d010b57c1d0cfd623a84d6 ]

These tracepoints collect different information: the create case does
not open a file, so there's no nf_file available.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:01 +01:00
Chuck Lever
8135682ff8 NFSD: Clean up unused code after rhashtable conversion
[ Upstream commit 0ec8e9d1539a7b8109a554028bbce441052f847e ]

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:01 +01:00
Chuck Lever
fb4d9b9e07 NFSD: Convert the filecache to use rhashtable
[ Upstream commit ce502f81ba884c1fe45dc0ebddbcaaa4ec0fc5fb ]

Enable the filecache hash table to start small, then grow with the
workload. Smaller server deployments benefit because there should
be lower memory utilization. Larger server deployments should see
improved scaling with the number of open files.

Suggested-by: Jeff Layton <jlayton@kernel.org>
Suggested-by: Dave Chinner <david@fromorbit.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>
2024-11-19 12:28:01 +01:00
Chuck Lever
304260c184 NFSD: Set up an rhashtable for the filecache
[ Upstream commit fc22945ecc2a0a028f3683115f98a922d506c284 ]

Add code to initialize and tear down an rhashtable. The rhashtable
is not used yet.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:01 +01:00
Chuck Lever
5d5d11d1ab NFSD: Replace the "init once" mechanism
[ Upstream commit c7b824c3d06c85e054caf86e227255112c5e3c38 ]

In a moment, the nfsd_file_hashtbl global will be replaced with an
rhashtable. Replace the one or two spots that need to check if the
hash table is available. We can easily reuse the SHUTDOWN flag for
this purpose.

Document that this mechanism relies on callers to hold the
nfsd_mutex to prevent init, shutdown, and purging to run
concurrently.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:01 +01:00
Chuck Lever
c5c427f95c NFSD: Remove nfsd_file::nf_hashval
[ Upstream commit f0743c2b25c65debd4f599a7c861428cd9de5906 ]

The value in this field can always be computed from nf_inode, thus
it is no longer used.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:01 +01:00
Chuck Lever
76fe92d538 NFSD: nfsd_file_hash_remove can compute hashval
[ Upstream commit cb7ec76e73ff6640241c8f1f2f35c81d4005a2d6 ]

Remove an unnecessary use of nf_hashval.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:01 +01:00
Chuck Lever
d365398d77 NFSD: Refactor __nfsd_file_close_inode()
[ Upstream commit a845511007a63467fee575353c706806c21218b1 ]

The code that computes the hashval is the same in both callers.

To prevent them from going stale, reframe the documenting comments
to remove descriptions of the underlying hash table structure, which
is about to be replaced.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:01 +01:00
Chuck Lever
adfe497c23 NFSD: nfsd_file_unhash can compute hashval from nf->nf_inode
[ Upstream commit 8755326399f471ec3b31e2ab8c5074c0d28a0fb5 ]

Remove an unnecessary usage of nf_hashval.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:01 +01:00
Chuck Lever
be3cb94280 NFSD: Remove lockdep assertion from unhash_and_release_locked()
[ Upstream commit f53cef15dddec7203df702cdc62e554190385450 ]

IIUC, holding the hash bucket lock is needed only in
nfsd_file_unhash, and there is already a lockdep assertion there.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:01 +01:00
Chuck Lever
4f7dbf0537 NFSD: No longer record nf_hashval in the trace log
[ Upstream commit 54f7df7094b329ca35d9f9808692bb16c48b13e9 ]

I'm about to replace nfsd_file_hashtbl with an rhashtable. The
individual hash values will no longer be visible or relevant, so
remove them from the tracepoints.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:00 +01:00
Chuck Lever
1df5db6e78 NFSD: Never call nfsd_file_gc() in foreground paths
[ Upstream commit 6df19411367a5fb4ef61854cbd1af269c077f917 ]

The checks in nfsd_file_acquire() and nfsd_file_put() that directly
invoke filecache garbage collection are intended to keep cache
occupancy between a low- and high-watermark. The reason to limit the
capacity of the filecache is to keep filecache lookups reasonably
fast.

However, invoking garbage collection at those points has some
undesirable negative impacts. Files that are held open by NFSv4
clients often push the occupancy of the filecache over these
watermarks. At that point:

- Every call to nfsd_file_acquire() and nfsd_file_put() results in
  an LRU walk. This has the same effect on lookup latency as long
  chains in the hash table.
- Garbage collection will then run on every nfsd thread, causing a
  lot of unnecessary lock contention.
- Limiting cache capacity pushes out files used only by NFSv3
  clients, which are the type of files the filecache is supposed to
  help.

To address those negative impacts, remove the direct calls to the
garbage collector. Subsequent patches will address maintaining
lookup efficiency as cache capacity increases.

Suggested-by: Wang Yugui <wangyugui@e16-tech.com>
Suggested-by: Dave Chinner <david@fromorbit.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>
2024-11-19 12:28:00 +01:00
Chuck Lever
1d683366d4 NFSD: Fix the filecache LRU shrinker
[ Upstream commit edead3a55804739b2e4af0f35e9c7326264e7b22 ]

Without LRU item rotation, the shrinker visits only a few items on
the end of the LRU list, and those would always be long-term OPEN
files for NFSv4 workloads. That makes the filecache shrinker
completely ineffective.

Adopt the same strategy as the inode LRU by using LRU_ROTATE.

Suggested-by: Dave Chinner <david@fromorbit.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>
2024-11-19 12:28:00 +01:00
Chuck Lever
f65a30361a NFSD: Leave open files out of the filecache LRU
[ Upstream commit 4a0e73e635e3f36b616ad5c943e3d23debe4632f ]

There have been reports of problems when running fstests generic/531
against Linux NFS servers with NFSv4. The NFS server that hosts the
test's SCRATCH_DEV suffers from CPU soft lock-ups during the test.
Analysis shows that:

fs/nfsd/filecache.c
 482                 ret = list_lru_walk(&nfsd_file_lru,
 483                                 nfsd_file_lru_cb,
 484                                 &head, LONG_MAX);

causes nfsd_file_gc() to walk the entire length of the filecache LRU
list every time it is called (which is quite frequently). The walk
holds a spinlock the entire time that prevents other nfsd threads
from accessing the filecache.

What's more, for NFSv4 workloads, none of the items that are visited
during this walk may be evicted, since they are all files that are
held OPEN by NFS clients.

Address this by ensuring that open files are not kept on the LRU
list.

Reported-by: Frank van der Linden <fllinden@amazon.com>
Reported-by: Wang Yugui <wangyugui@e16-tech.com>
Link: https://bugzilla.linux-nfs.org/show_bug.cgi?id=386
Suggested-by: Trond Myklebust <trond.myklebust@hammerspace.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>
2024-11-19 12:28:00 +01:00
Chuck Lever
4155bf65c7 NFSD: Trace filecache LRU activity
[ Upstream commit c46203acddd9b9200dbc53d0603c97355fd3a03b ]

Observe the operation of garbage collection and the lifetime of
filecache items.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:00 +01:00
Chuck Lever
2e3445246e NFSD: WARN when freeing an item still linked via nf_lru
[ Upstream commit 668ed92e651d3c25f9b6e8cb7ceca54d00daa96d ]

Add a guardrail to prevent freeing memory that is still on a list.
This includes either a dispose list or the LRU list.

This is the sign of a bug, but this class of bugs can be detected
so that they don't endanger system stability, especially while
debugging.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:00 +01:00
Chuck Lever
2310e47e13 NFSD: Hook up the filecache stat file
[ Upstream commit 2e6c6e4c4375bfd3defa5b1ff3604d9f33d1c936 ]

There has always been the capability of exporting filecache metrics
via /proc, but it was never hooked up. Let's surface these metrics
to enable better observability of the filecache.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:00 +01:00
Chuck Lever
08cf06f7ea NFSD: Zero counters when the filecache is re-initialized
[ Upstream commit 8b330f78040cbe16cf8029df70391b2a491f17e2 ]

If nfsd_file_cache_init() is called after a shutdown, be sure the
stat counters are reset.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:00 +01:00
Chuck Lever
a679a24e03 NFSD: Record number of flush calls
[ Upstream commit df2aff524faceaf743b7c5ab0f4fb86cb511f782 ]

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:00 +01:00
Chuck Lever
3e67c0dce1 NFSD: Report the number of items evicted by the LRU walk
[ Upstream commit 94660cc19c75083af046b0f8362e3d3bc2eba21d ]

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:00 +01:00
Chuck Lever
d2190956b0 NFSD: Refactor nfsd_file_lru_scan()
[ Upstream commit 39f1d1ff8148902c5692ffb0e1c4479416ab44a7 ]

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:00 +01:00
Chuck Lever
f2f80d62e1 NFSD: Refactor nfsd_file_gc()
[ Upstream commit 3bc6d3470fe412f818f9bff6b71d1be3a76af8f3 ]

Refactor nfsd_file_gc() to use the new list_lru helper.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:00 +01:00
Chuck Lever
2103e0252c NFSD: Add nfsd_file_lru_dispose_list() helper
[ Upstream commit 0bac5a264d9a923f5b01f3521e1519a8d0358342 ]

Refactor the invariant part of nfsd_file_lru_walk_list() into a
separate helper function.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:00 +01:00
Chuck Lever
8a559507dc NFSD: Report average age of filecache items
[ Upstream commit 904940e94a887701db24401e3ed6928a1d4e329f ]

This is a measure of how long items stay in the filecache, to help
assess how efficient the cache is.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:00 +01:00
Chuck Lever
5164b98baf NFSD: Report count of freed filecache items
[ Upstream commit d63293272abb51c02457f1017dfd61c3270d9ae3 ]

Surface the count of freed nfsd_file items.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:28:00 +01:00
Chuck Lever
359bbdb6f0 NFSD: Report count of calls to nfsd_file_acquire()
[ Upstream commit 29d4bdbbb910f33d6058d2c51278f00f656df325 ]

Count the number of successful acquisitions that did not create a
file (ie, acquisitions that do not result in a compulsory cache
miss). This count can be compared directly with the reported hit
count to compute a hit ratio.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:59 +01:00
Chuck Lever
6eaf4cc583 NFSD: Report filecache LRU size
[ Upstream commit 0fd244c115f0321fc5e34ad2291f2a572508e3f7 ]

Surface the NFSD filecache's LRU list length to help field
troubleshooters monitor filecache issues.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:59 +01:00
Chuck Lever
0c9dcf0d22 NFSD: Demote a WARN to a pr_warn()
[ Upstream commit ca3f9acb6d3faf78da2b63324f7c737dbddf7f69 ]

The call trace doesn't add much value, but it sure is noisy.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:59 +01:00
Colin Ian King
3d521baa0c nfsd: remove redundant assignment to variable len
[ Upstream commit 842e00ac3aa3b4a4f7f750c8ab54f8578fc875d3 ]

Variable len is being assigned a value zero and this is never
read, it is being re-assigned later. The assignment is redundant
and can be removed.

Cleans up clang scan-build warning:
fs/nfsd/nfsctl.c:636:2: warning: Value stored to 'len' is never read

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:59 +01:00
Zhang Jiaming
f739c31d1d NFSD: Fix space and spelling mistake
[ Upstream commit f532c9ff103897be0e2a787c0876683c3dc39ed3 ]

Add a blank space after ','.
Change 'succesful' to 'successful'.

Signed-off-by: Zhang Jiaming <jiaming@nfschina.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:59 +01:00
Jeff Layton
92c9b806c7 nfsd: eliminate the NFSD_FILE_BREAK_* flags
[ Upstream commit 23ba98de6dcec665e15c0ca19244379bb0d30932 ]

We had a report from the spring Bake-a-thon of data corruption in some
nfstest_interop tests. Looking at the traces showed the NFS server
allowing a v3 WRITE to proceed while a read delegation was still
outstanding.

Currently, we only set NFSD_FILE_BREAK_* flags if
NFSD_MAY_NOT_BREAK_LEASE was set when we call nfsd_file_alloc.
NFSD_MAY_NOT_BREAK_LEASE was intended to be set when finding files for
COMMIT ops, where we need a writeable filehandle but don't need to
break read leases.

It doesn't make any sense to consult that flag when allocating a file
since the file may be used on subsequent calls where we do want to break
the lease (and the usage of it here seems to be reverse from what it
should be anyway).

Also, after calling nfsd_open_break_lease, we don't want to clear the
BREAK_* bits. A lease could end up being set on it later (more than
once) and we need to be able to break those leases as well.

This means that the NFSD_FILE_BREAK_* flags now just mirror
NFSD_MAY_{READ,WRITE} flags, so there's no need for them at all. Just
drop those flags and unconditionally call nfsd_open_break_lease every
time.

Reported-by: Olga Kornieskaia <kolga@netapp.com>
Link: https://bugzilla.redhat.com/show_bug.cgi?id=2107360
Fixes: 65294c1f2c5e (nfsd: add a new struct file caching facility to nfsd)
Cc: <stable@vger.kernel.org> # 5.4.x : bb283ca18d1e NFSD: Clean up the show_nf_flags() macro
Cc: <stable@vger.kernel.org> # 5.4.x
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>
2024-11-19 12:27:59 +01:00
Chuck Lever
38aea79732 NFSD: Decode NFSv4 birth time attribute
[ Upstream commit 5b2f3e0777da2a5dd62824bbe2fdab1d12caaf8f ]

NFSD has advertised support for the NFSv4 time_create attribute
since commit e377a3e698fb ("nfsd: Add support for the birth time
attribute").

Igor Mammedov reports that Mac OS clients attempt to set the NFSv4
birth time attribute via OPEN(CREATE) and SETATTR if the server
indicates that it supports it, but since the above commit was
merged, those attempts now fail.

Table 5 in RFC 8881 lists the time_create attribute as one that can
be both set and retrieved, but the above commit did not add server
support for clients to provide a time_create attribute. IMO that's
a bug in our implementation of the NFSv4 protocol, which this commit
addresses.

Whether NFSD silently ignores the new birth time or actually sets it
is another matter. I haven't found another filesystem service in the
Linux kernel that enables users or clients to modify a file's birth
time attribute.

This commit reflects my (perhaps incorrect) understanding of whether
Linux users can set a file's birth time. NFSD will now recognize a
time_create attribute but it ignores its value. It clears the
time_create bit in the returned attribute bitmask to indicate that
the value was not used.

Reported-by: Igor Mammedov <imammedo@redhat.com>
Fixes: e377a3e698fb ("nfsd: Add support for the birth time attribute")
Tested-by: Igor Mammedov <imammedo@redhat.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>
2024-11-19 12:27:59 +01:00
Chuck Lever
812ad3cdc4 NFSD: Fix potential use-after-free in nfsd_file_put()
[ Upstream commit b6c71c66b0ad8f2b59d9bc08c7a5079b110bec01 ]

nfsd_file_put_noref() can free @nf, so don't dereference @nf
immediately upon return from nfsd_file_put_noref().

Suggested-by: Trond Myklebust <trondmy@hammerspace.com>
Fixes: 999397926ab3 ("nfsd: Clean up nfsd_file_put()")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:58 +01:00
Chuck Lever
b09116ac30 NFSD: nfsd_file_put() can sleep
[ Upstream commit 08af54b3e5729bc1d56ad3190af811301bdc37a1 ]

Now that there are no more callers of nfsd_file_put() that might
hold a spin lock, ensure the lockdep infrastructure can catch
newly introduced calls to nfsd_file_put() made while a spinlock
is held.

Link: https://lore.kernel.org/linux-nfs/ece7fd1d-5fb3-5155-54ba-347cfc19bd9a@oracle.com/T/#mf1855552570cf9a9c80d1e49d91438cd9085aada
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: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:58 +01:00
Chuck Lever
bb58cbbf0a NFSD: Add documenting comment for nfsd4_release_lockowner()
[ Upstream commit 043862b09cc00273e35e6c3a6389957953a34207 ]

And return explicit nfserr values that match what is documented in the
new comment / API contract.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:58 +01:00
Chuck Lever
8b8f536a81 NFSD: Modernize nfsd4_release_lockowner()
[ Upstream commit bd8fdb6e545f950f4654a9a10d7e819ad48146e5 ]

Refactor: Use existing helpers that other lock operations use. This
change removes several automatic variables, so re-organize the
variable declarations for readability.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:58 +01:00
Julian Schroeder
9ca8d2154e nfsd: destroy percpu stats counters after reply cache shutdown
[ Upstream commit fd5e363eac77ef81542db77ddad0559fa0f9204e ]

Upon nfsd shutdown any pending DRC cache is freed. DRC cache use is
tracked via a percpu counter. In the current code the percpu counter
is destroyed before. If any pending cache is still present,
percpu_counter_add is called with a percpu counter==NULL. This causes
a kernel crash.
The solution is to destroy the percpu counter after the cache is freed.

Fixes: e567b98ce9a4b (“nfsd: protect concurrent access to nfsd stats counters”)
Signed-off-by: Julian Schroeder <jumaco@amazon.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:58 +01:00
Zhang Xiaoxu
6c1ecdcf60 nfsd: Fix null-ptr-deref in nfsd_fill_super()
[ Upstream commit 6f6f84aa215f7b6665ccbb937db50860f9ec2989 ]

KASAN report null-ptr-deref as follows:

  BUG: KASAN: null-ptr-deref in nfsd_fill_super+0xc6/0xe0 [nfsd]
  Write of size 8 at addr 000000000000005d by task a.out/852

  CPU: 7 PID: 852 Comm: a.out Not tainted 5.18.0-rc7-dirty #66
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-1.fc33 04/01/2014
  Call Trace:
   <TASK>
   dump_stack_lvl+0x34/0x44
   kasan_report+0xab/0x120
   ? nfsd_mkdir+0x71/0x1c0 [nfsd]
   ? nfsd_fill_super+0xc6/0xe0 [nfsd]
   nfsd_fill_super+0xc6/0xe0 [nfsd]
   ? nfsd_mkdir+0x1c0/0x1c0 [nfsd]
   get_tree_keyed+0x8e/0x100
   vfs_get_tree+0x41/0xf0
   __do_sys_fsconfig+0x590/0x670
   ? fscontext_read+0x180/0x180
   ? anon_inode_getfd+0x4f/0x70
   do_syscall_64+0x35/0x80
   entry_SYSCALL_64_after_hwframe+0x44/0xae

This can be reproduce by concurrent operations:
	1. fsopen(nfsd)/fsconfig
	2. insmod/rmmod nfsd

Since the nfsd file system is registered before than nfsd_net allocated,
the caller may get the file_system_type and use the nfsd_net before it
allocated, then null-ptr-deref occurred.

So init_nfsd() should call register_filesystem() last.

Fixes: bd5ae9288d64 ("nfsd: register pernet ops last, unregister first")
Signed-off-by: Zhang Xiaoxu <zhangxiaoxu5@huawei.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:58 +01:00
Zhang Xiaoxu
39414a484a nfsd: Unregister the cld notifier when laundry_wq create failed
[ Upstream commit 62fdb65edb6c43306c774939001f3a00974832aa ]

If laundry_wq create failed, the cld notifier should be unregistered.

Signed-off-by: Zhang Xiaoxu <zhangxiaoxu5@huawei.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:58 +01:00
Chuck Lever
7da9080d87 SUNRPC: Use RMW bitops in single-threaded hot paths
[ Upstream commit 28df0988815f63e2af5e6718193c9f68681ad7ff ]

I noticed CPU pipeline stalls while using perf.

Once an svc thread is scheduled and executing an RPC, no other
processes will touch svc_rqst::rq_flags. Thus bus-locked atomics are
not needed outside the svc thread scheduler.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:58 +01:00
Chuck Lever
4338883018 NFSD: Clean up the show_nf_flags() macro
[ Upstream commit bb283ca18d1e67c82d22a329c96c9d6036a74790 ]

The flags are defined using C macros, so TRACE_DEFINE_ENUM is
unnecessary.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:58 +01:00
Chuck Lever
47ef8b0821 NFSD: Trace filecache opens
[ Upstream commit 0122e882119ddbd9efa6edfeeac3f5c704a7aeea ]

Instrument calls to nfsd_open_verified() to get a sense of the
filecache hit rate.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:58 +01:00
Chuck Lever
09e30c0ad5 NFSD: Move documenting comment for nfsd4_process_open2()
[ Upstream commit 7e2ce0cc15a509b859199235a2bad9cece00f67a ]

Clean up nfsd4_open() by converting a large comment at the only
call site for nfsd4_process_open2() to a kerneldoc comment in
front of that function.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:58 +01:00
Chuck Lever
e139ce38c4 NFSD: Fix whitespace
[ Upstream commit 26320d7e317c37404c811603d50d811132aef78c ]

Clean up: Pull case arms back one tab stop to conform every other
switch statement in fs/nfsd/nfs4proc.c.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:57 +01:00
Chuck Lever
1b66509ece NFSD: Remove dprintk call sites from tail of nfsd4_open()
[ Upstream commit f67a16b147045815b6aaafeef8663e5faeb6d569 ]

Clean up: These relics are not likely to benefit server
administrators.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:57 +01:00
Chuck Lever
96f1516e3e NFSD: Instantiate a struct file when creating a regular NFSv4 file
[ Upstream commit fb70bf124b051d4ded4ce57511dfec6d3ebf2b43 ]

There have been reports of races that cause NFSv4 OPEN(CREATE) to
return an error even though the requested file was created. NFSv4
does not provide a status code for this case.

To mitigate some of these problems, reorganize the NFSv4
OPEN(CREATE) logic to allocate resources before the file is actually
created, and open the new file while the parent directory is still
locked.

Two new APIs are added:

+ Add an API that works like nfsd_file_acquire() but does not open
the underlying file. The OPEN(CREATE) path can use this API when it
already has an open file.

+ Add an API that is kin to dentry_open(). NFSD needs to create a
file and grab an open "struct file *" atomically. The
alloc_empty_file() has to be done before the inode create. If it
fails (for example, because the NFS server has exceeded its
max_files limit), we avoid creating the file and can still return
an error to the NFS client.

BugLink: https://bugzilla.linux-nfs.org/show_bug.cgi?id=382
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: JianHong Yin <jiyin@redhat.com>
[ cel: backported to 5.10.y, prior to idmapped mounts ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:57 +01:00
Chuck Lever
52b01f1e64 NFSD: Clean up nfsd_open_verified()
[ Upstream commit f4d84c52643ae1d63a8e73e2585464470e7944d1 ]

Its only caller always passes S_IFREG as the @type parameter. As an
additional clean-up, add a kerneldoc comment.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:57 +01:00
Chuck Lever
0d45ecb602 NFSD: Remove do_nfsd_create()
[ Upstream commit 1c388f27759c5d9271d4fca081f7ee138986eb7d ]

Now that its two callers have their own version-specific instance of
this function, do_nfsd_create() is no longer used.

[ cel: backported to 5.10.y, prior to idmapped mounts ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:57 +01:00
Chuck Lever
381d307366 NFSD: Refactor NFSv4 OPEN(CREATE)
[ Upstream commit 254454a5aa4a9f696d6bae080c08d5863e650f49 ]

Copy do_nfsd_create() to nfs4proc.c and remove NFSv3-specific logic.

[ cel: backported to 5.10.y, prior to idmapped mounts ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:57 +01:00
Chuck Lever
68549f7a67 NFSD: Refactor NFSv3 CREATE
[ Upstream commit df9606abddfb01090d5ece7dcc2441d848f690f0 ]

The NFSv3 CREATE and NFSv4 OPEN(CREATE) use cases are about to
diverge such that it makes sense to split do_nfsd_create() into one
version for NFSv3 and one for NFSv4.

As a first step, copy do_nfsd_create() to nfs3proc.c and remove
NFSv4-specific logic.

One immediate legibility benefit is that the logic for handling
NFSv3 createhow is now quite straightforward. NFSv4 createhow
has some subtleties that IMO do not belong in generic code.

[ cel: backported to 5.10.y, prior to idmapped mounts ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:57 +01:00
Chuck Lever
e47a03cb8c NFSD: Refactor nfsd_create_setattr()
[ Upstream commit 5f46e950c395b9c14c282b53ba78c5fd46d6c256 ]

I'd like to move do_nfsd_create() out of vfs.c. Therefore
nfsd_create_setattr() needs to be made publicly visible.

Note that both call sites in vfs.c commit both the new object and
its parent directory, so just combine those common metadata commits
into nfsd_create_setattr().

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:57 +01:00
Chuck Lever
ae6e6cbebe NFSD: Avoid calling fh_drop_write() twice in do_nfsd_create()
[ Upstream commit 14ee45b70dd0d9ae76fb066cd8c0652d657353f6 ]

Clean up: The "out" label already invokes fh_drop_write().

Note that fh_drop_write() is already careful not to invoke
mnt_drop_write() if either it has already been done or there is
nothing to drop. Therefore no change in behavior is expected.

[ cel: backported to 5.10.y, prior to idmapped mounts ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:57 +01:00
Chuck Lever
ffa8158613 NFSD: Clean up nfsd3_proc_create()
[ Upstream commit e61568599c9ad638fdaba150fee07d7065e31851 ]

As near as I can tell, mode bit masking and setting S_IFREG is
already done by do_nfsd_create() and vfs_create(). The NFSv4 path
(do_open_lookup), for example, does not bother with this special
processing.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:57 +01:00
Dai Ngo
deb077af3e NFSD: Show state of courtesy client in client info
[ Upstream commit e9488d5ae13c0a72223c507e2508dc2ac66cad4f ]

Update client_info_show to show state of courtesy client
and seconds since last renew.

Reviewed-by: J. Bruce Fields <bfields@fieldses.org>
Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:57 +01:00
Dai Ngo
d7dd55b38e NFSD: add support for lock conflict to courteous server
[ Upstream commit 27431affb0dbc259ac6ffe6071243a576c8f38f1 ]

This patch allows expired client with lock state to be in COURTESY
state. Lock conflict with COURTESY client is resolved by the fs/lock
code using the lm_lock_expirable and lm_expire_lock callback in the
struct lock_manager_operations.

If conflict client is in COURTESY state, set it to EXPIRABLE and
schedule the laundromat to run immediately to expire the client. The
callback lm_expire_lock waits for the laundromat to flush its work
queue before returning to caller.

Reviewed-by: J. Bruce Fields <bfields@fieldses.org>
Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:57 +01:00
Dai Ngo
08d438e1aa NFSD: move create/destroy of laundry_wq to init_nfsd and exit_nfsd
[ Upstream commit d76cc46b37e123e8d245cc3490978dbda56f979d ]

This patch moves create/destroy of laundry_wq from nfs4_state_start
and nfs4_state_shutdown_net to init_nfsd and exit_nfsd to prevent
the laundromat from being freed while a thread is processing a
conflicting lock.

Reviewed-by: J. Bruce Fields <bfields@fieldses.org>
Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:56 +01:00
Dai Ngo
1657b2fb98 NFSD: add support for share reservation conflict to courteous server
[ Upstream commit 3d69427151806656abf129342028f3f4e5e1fee0 ]

This patch allows expired client with open state to be in COURTESY
state. Share/access conflict with COURTESY client is resolved by
setting COURTESY client to EXPIRABLE state, schedule laundromat
to run and returning nfserr_jukebox to the request client.

Reviewed-by: J. Bruce Fields <bfields@fieldses.org>
Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:56 +01:00
Dai Ngo
eb360efd38 NFSD: add courteous server support for thread with only delegation
[ Upstream commit 66af25799940b26efd41ea6e648f75c41a48a2c2 ]

This patch provides courteous server support for delegation only.
Only expired client with delegation but no conflict and no open
or lock state is allowed to be in COURTESY state.

Delegation conflict with COURTESY/EXPIRABLE client is resolved by
setting it to EXPIRABLE, queue work for the laundromat and return
delay to the caller. Conflict is resolved when the laudromat runs
and expires the EXIRABLE client while the NFS client retries the
OPEN request. Local thread request that gets conflict is doing the
retry in _break_lease.

Client in COURTESY or EXPIRABLE state is allowed to reconnect and
continues to have access to its state. Access to the nfs4_client by
the reconnecting thread and the laundromat is serialized via the
client_lock.

Reviewed-by: J. Bruce Fields <bfields@fieldses.org>
Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:56 +01:00
Chuck Lever
d98ea952eb NFSD: Clean up nfsd_splice_actor()
[ Upstream commit 91e23b1c39820bfed642119ff6b6ef9f43cf09ce ]

nfsd_splice_actor() checks that the page being spliced does not
match the previous element in the svc_rqst::rq_pages array. We
believe this is to prevent a double put_page() in cases where the
READ payload is partially contained in the xdr_buf's head buffer.

However, the NFSD READ proc functions no longer place any part of
the READ payload in the head buffer, in order to properly support
NFS/RDMA READ with Write chunks. Therefore, simplify the logic in
nfsd_splice_actor() to remove this unnecessary check.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:56 +01:00
Amir Goldstein
924ad2359b nfsd: use fsnotify group lock helpers
[ Upstream commit b8962a9d8cc2d8c93362e2f684091c79f702f6f3 ]

Before commit 9542e6a643fc6 ("nfsd: Containerise filecache laundrette")
nfsd would close open files in direct reclaim context and that could
cause a deadlock when fsnotify mark allocation went into direct reclaim
and nfsd shrinker tried to free existing fsnotify marks.

To avoid issues like this in future code, set the FSNOTIFY_GROUP_NOFS
flag on nfsd fsnotify group to prevent going into direct reclaim from
fsnotify_add_inode_mark().

Link: https://lore.kernel.org/r/20220422120327.3459282-10-amir73il@gmail.com
Suggested-by: Jan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20220321112310.vpr7oxro2xkz5llh@quack3.lan/
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:55 +01:00
Amir Goldstein
ef9c24cf07 fsnotify: pass flags argument to fsnotify_alloc_group()
[ Upstream commit 867a448d587e7fa845bceaf4ee1c632448f2a9fa ]

Add flags argument to fsnotify_alloc_group(), define and use the flag
FSNOTIFY_GROUP_USER in inotify and fanotify instead of the helper
fsnotify_alloc_user_group() to indicate user allocation.

Although the flag FSNOTIFY_GROUP_USER is currently not used after group
allocation, we store the flags argument in the group struct for future
use of other group flags.

Link: https://lore.kernel.org/r/20220422120327.3459282-5-amir73il@gmail.com
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:55 +01:00
Trond Myklebust
12c4345fdb nfsd: Clean up nfsd_file_put()
[ Upstream commit 999397926ab3f78c7d1235cc4ca6e3c89d2769bf ]

Make it a little less racy, by removing the refcount_read() test. Then
remove the redundant 'is_hashed' variable.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:55 +01:00
Trond Myklebust
3850692c41 nfsd: Fix a write performance regression
[ Upstream commit 6b8a94332ee4f7d9a8ae0cbac7609f79c212f06c ]

The call to filemap_flush() in nfsd_file_put() is there to ensure that
we clear out any writes belonging to a NFSv3 client relatively quickly
and avoid situations where the file can't be evicted by the garbage
collector. It also ensures that we detect write errors quickly.

The problem is this causes a regression in performance for some
workloads.

So try to improve matters by deferring writeback until we're ready to
close the file, and need to detect errors so that we can force the
client to resend.

Tested-by: Jan Kara <jack@suse.cz>
Fixes: b6669305d35a ("nfsd: Reduce the number of calls to nfsd_file_gc()")
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Link: https://lore.kernel.org/all/20220330103457.r4xrhy2d6nhtouzk@quack3.lan
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:55 +01:00
Haowen Bai
097f4985e1 SUNRPC: Return true/false (not 1/0) from bool functions
[ Upstream commit 5f7b839d47dbc74cf4a07beeab5191f93678673e ]

Return boolean values ("true" or "false") instead of 1 or 0 from bool
functions.  This fixes the following warnings from coccicheck:

./fs/nfsd/nfs2acl.c:289:9-10: WARNING: return of 0/1 in function
'nfsaclsvc_encode_accessres' with return type bool
./fs/nfsd/nfs2acl.c:252:9-10: WARNING: return of 0/1 in function
'nfsaclsvc_encode_getaclres' with return type bool

Signed-off-by: Haowen Bai <baihaowen@meizu.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:54 +01:00
Jakob Koschel
58137c0ba5 nfsd: fix using the correct variable for sizeof()
[ Upstream commit 4fc5f5346592cdc91689455d83885b0af65d71b8 ]

While the original code is valid, it is not the obvious choice for the
sizeof() call and in preparation to limit the scope of the list iterator
variable the sizeof should be changed to the size of the destination.

Signed-off-by: Jakob Koschel <jakobkoschel@gmail.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:54 +01:00
Chuck Lever
c4ed3e405e NFSD: Clean up _lm_ operation names
[ Upstream commit 35aff0678f99b0623bb72d50112de9e163a19559 ]

The common practice is to name function instances the same as the
method names, but with a uniquifying prefix. Commit aef9583b234a
("NFSD: Get reference of lockowner when coping file_lock") missed
this -- the new function names should both have been of the form
"nfsd4_lm_*".

Before more lock manager operations are added in NFSD, rename these
two functions for consistency.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:54 +01:00
Chuck Lever
3cc88ae66e NFSD: Remove CONFIG_NFSD_V3
[ Upstream commit 5f9a62ff7d2808c7b56c0ec90f3b7eae5872afe6 ]

Eventually support for NFSv2 in the Linux NFS server is to be
deprecated and then removed.

However, NFSv2 is the "always supported" version that is available
as soon as CONFIG_NFSD is set.  Before NFSv2 support can be removed,
we need to choose a different "always supported" version.

This patch removes CONFIG_NFSD_V3 so that NFSv3 is always supported,
as NFSv2 is today. When NFSv2 support is removed, NFSv3 will become
the only "always supported" NFS version.

The defconfigs still need to be updated to remove CONFIG_NFSD_V3=y.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:54 +01:00
Chuck Lever
2c57725d69 NFSD: Move svc_serv_ops::svo_function into struct svc_serv
[ Upstream commit 37902c6313090235c847af89c5515591261ee338 ]

Hoist svo_function back into svc_serv and remove struct
svc_serv_ops, since the struct is now devoid of fields.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:54 +01:00
Chuck Lever
2b70332cac NFSD: Remove svc_serv_ops::svo_module
[ Upstream commit f49169c97fceb21ad6a0aaf671c50b0f520f15a5 ]

struct svc_serv_ops is about to be removed.

Neil Brown says:
> I suspect svo_module can go as well - I don't think the thread is
> ever the thing that primarily keeps a module active.

A random sample of kthread_create() callers shows sunrpc is the only
one that manages module reference count in this way.

Suggested-by: Neil Brown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:54 +01:00
Chuck Lever
e3a0f44371 SUNRPC: Remove svc_shutdown_net()
[ Upstream commit c7d7ec8f043e53ad16e30f5ebb8b9df415ec0f2b ]

Clean up: svc_shutdown_net() now does nothing but call
svc_close_net(). Replace all external call sites.

svc_close_net() is renamed to be the inverse of svc_xprt_create().

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:54 +01:00
Chuck Lever
758fcc041e SUNRPC: Rename svc_close_xprt()
[ Upstream commit 4355d767a21b9445958fc11bce9a9701f76529d3 ]

Clean up: Use the "svc_xprt_<task>" function naming convention as
is used for other external APIs.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:54 +01:00
Chuck Lever
bee0c024d6 SUNRPC: Rename svc_create_xprt()
[ Upstream commit 352ad31448fecc78a2e9b78da64eea5d63b8d0ce ]

Clean up: Use the "svc_xprt_<task>" function naming convention as
is used for other external APIs.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:54 +01:00
Chuck Lever
9b54c62e38 SUNRPC: Remove svo_shutdown method
[ Upstream commit 87cdd8641c8a1ec6afd2468265e20840a57fd888 ]

Clean up. Neil observed that "any code that calls svc_shutdown_net()
knows what the shutdown function should be, and so can call it
directly."

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: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:54 +01:00
Chuck Lever
de06412bad SUNRPC: Remove the .svo_enqueue_xprt method
[ Upstream commit a9ff2e99e9fa501ec965da03c18a5422b37a2f44 ]

We have never been able to track down and address the underlying
cause of the performance issues with workqueue-based service
support. svo_enqueue_xprt is called multiple times per RPC, so
it adds instruction path length, but always ends up at the same
function: svc_xprt_do_enqueue(). We do not anticipate needing
this flexibility for dynamic nfsd thread management support.

As a micro-optimization, remove .svo_enqueue_xprt because
Spectre/Meltdown makes virtual function calls more costly.

This change essentially reverts commit b9e13cdfac70 ("nfsd/sunrpc:
turn enqueueing a svc_xprt into a svc_serv operation").

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:53 +01:00
Chuck Lever
265c1446e6 NFSD: Streamline the rare "found" case
[ Upstream commit add1511c38166cf1036765f8c4aa939f0275a799 ]

Move a rarely called function call site out of the hot path.

This is an exceptionally small improvement because the compiler
inlines most of the functions that nfsd_cache_lookup() calls.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:53 +01:00
Chuck Lever
8517132f6f NFSD: Skip extra computation for RC_NOCACHE case
[ Upstream commit 0f29ce32fbc56cfdb304eec8a4deb920ccfd89c3 ]

Force the compiler to skip unneeded initialization for cases that
don't need those values. For example, NFSv4 COMPOUND operations are
RC_NOCACHE.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:53 +01:00
Chuck Lever
cfdba1e2d8 NFSD: De-duplicate hash bucket indexing
[ Upstream commit 378a6109dd142a678f629b740f558365150f60f9 ]

Clean up: The details of finding the right hash bucket are exactly
the same in both nfsd_cache_lookup() and nfsd_cache_update().

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:53 +01:00
Ondrej Valousek
ab902aa1e0 nfsd: Add support for the birth time attribute
[ Upstream commit e377a3e698fb56cb63f6bddbebe7da76dc37e316 ]

For filesystems that supports "btime" timestamp (i.e. most modern
filesystems do) we share it via kernel nfsd. Btime support for NFS
client has already been added by Trond recently.

Suggested-by: Bruce Fields <bfields@fieldses.org>
Signed-off-by: Ondrej Valousek <ondrej.valousek.xm@renesas.com>
[ cel: addressed some whitespace/checkpatch nits ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:53 +01:00
Chuck Lever
770a38d491 NFSD: Deprecate NFS_OFFSET_MAX
[ Upstream commit c306d737691ef84305d4ed0d302c63db2932f0bb ]

NFS_OFFSET_MAX was introduced way back in Linux v2.3.y before there
was a kernel-wide OFFSET_MAX value. As a clean up, replace the last
few uses of it with its generic equivalent, and get rid of it.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:53 +01:00
Chuck Lever
6accb417a3 NFSD: COMMIT operations must not return NFS?ERR_INVAL
[ Upstream commit 3f965021c8bc38965ecb1924f570c4842b33d408 ]

Since, well, forever, the Linux NFS server's nfsd_commit() function
has returned nfserr_inval when the passed-in byte range arguments
were non-sensical.

However, according to RFC 1813 section 3.3.21, NFSv3 COMMIT requests
are permitted to return only the following non-zero status codes:

      NFS3ERR_IO
      NFS3ERR_STALE
      NFS3ERR_BADHANDLE
      NFS3ERR_SERVERFAULT

NFS3ERR_INVAL is not included in that list. Likewise, NFS4ERR_INVAL
is not listed in the COMMIT row of Table 6 in RFC 8881.

RFC 7530 does permit COMMIT to return NFS4ERR_INVAL, but does not
specify when it can or should be used.

Instead of dropping or failing a COMMIT request in a byte range that
is not supported, turn it into a valid request by treating one or
both arguments as zero. Offset zero means start-of-file, count zero
means until-end-of-file, so we only ever extend the commit range.
NFS servers are always allowed to commit more and sooner than
requested.

The range check is no longer bounded by NFS_OFFSET_MAX, but rather
by the value that is returned in the maxfilesize field of the NFSv3
FSINFO procedure or the NFSv4 maxfilesize file attribute.

Note that this change results in a new pynfs failure:

CMT4     st_commit.testCommitOverflow                             : RUNNING
CMT4     st_commit.testCommitOverflow                             : FAILURE
           COMMIT with offset + count overflow should return
           NFS4ERR_INVAL, instead got NFS4_OK

IMO the test is not correct as written: RFC 8881 does not allow the
COMMIT operation to return NFS4ERR_INVAL.

Reported-by: Dan Aloni <dan.aloni@vastdata.com>
Cc: stable@vger.kernel.org
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Bruce Fields <bfields@fieldses.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:53 +01:00
Chuck Lever
f43151a538 NFSD: Fix NFSv3 SETATTR/CREATE's handling of large file sizes
[ Upstream commit a648fdeb7c0e17177a2280344d015dba3fbe3314 ]

iattr::ia_size is a loff_t, so these NFSv3 procedures must be
careful to deal with incoming client size values that are larger
than s64_max without corrupting the value.

Silently capping the value results in storing a different value
than the client passed in which is unexpected behavior, so remove
the min_t() check in decode_sattr3().

Note that RFC 1813 permits only the WRITE procedure to return
NFS3ERR_FBIG. We believe that NFSv3 reference implementations
also return NFS3ERR_FBIG when ia_size is too large.

Cc: stable@vger.kernel.org
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:53 +01:00
Chuck Lever
8e3fa632d4 NFSD: Fix ia_size underflow
[ Upstream commit e6faac3f58c7c4176b66f63def17a34232a17b0e ]

iattr::ia_size is a loff_t, which is a signed 64-bit type. NFSv3 and
NFSv4 both define file size as an unsigned 64-bit type. Thus there
is a range of valid file size values an NFS client can send that is
already larger than Linux can handle.

Currently decode_fattr4() dumps a full u64 value into ia_size. If
that value happens to be larger than S64_MAX, then ia_size
underflows. I'm about to fix up the NFSv3 behavior as well, so let's
catch the underflow in the common code path: nfsd_setattr().

Cc: stable@vger.kernel.org
[ cel: context adjusted, 2f221d6f7b88 has not been applied ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:53 +01:00
Chuck Lever
7bba5c16ef NFSD: Fix the behavior of READ near OFFSET_MAX
[ Upstream commit 0cb4d23ae08c48f6bf3c29a8e5c4a74b8388b960 ]

Dan Aloni reports:
> Due to commit 8cfb9015280d ("NFS: Always provide aligned buffers to
> the RPC read layers") on the client, a read of 0xfff is aligned up
> to server rsize of 0x1000.
>
> As a result, in a test where the server has a file of size
> 0x7fffffffffffffff, and the client tries to read from the offset
> 0x7ffffffffffff000, the read causes loff_t overflow in the server
> and it returns an NFS code of EINVAL to the client. The client as
> a result indefinitely retries the request.

The Linux NFS client does not handle NFS?ERR_INVAL, even though all
NFS specifications permit servers to return that status code for a
READ.

Instead of NFS?ERR_INVAL, have out-of-range READ requests succeed
and return a short result. Set the EOF flag in the result to prevent
the client from retrying the READ request. This behavior appears to
be consistent with Solaris NFS servers.

Note that NFSv3 and NFSv4 use u64 offset values on the wire. These
must be converted to loff_t internally before use -- an implicit
type cast is not adequate for this purpose. Otherwise VFS checks
against sb->s_maxbytes do not work properly.

Reported-by: Dan Aloni <dan.aloni@vastdata.com>
Cc: stable@vger.kernel.org
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:53 +01:00
J. Bruce Fields
7973cfdbf4 nfsd: fix crash on COPY_NOTIFY with special stateid
[ Upstream commit 074b07d94e0bb6ddce5690a9b7e2373088e8b33a ]

RTM says "If the special ONE stateid is passed to
nfs4_preprocess_stateid_op(), it returns status=0 but does not set
*cstid. nfsd4_copy_notify() depends on stid being set if status=0, and
thus can crash if the client sends the right COPY_NOTIFY RPC."

RFC 7862 says "The cna_src_stateid MUST refer to either open or locking
states provided earlier by the server.  If it is invalid, then the
operation MUST fail."

The RFC doesn't specify an error, and the choice doesn't matter much as
this is clearly illegal client behavior, but bad_stateid seems
reasonable.

Simplest is just to guarantee that nfs4_preprocess_stateid_op, called
with non-NULL cstid, errors out if it can't return a stateid.

Reported-by: rtm@csail.mit.edu
Fixes: 624322f1adc5 ("NFSD add COPY_NOTIFY operation")
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Olga Kornievskaia <kolga@netapp.com>
Tested-by: Olga Kornievskaia <kolga@netapp.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:53 +01:00
Chuck Lever
8cabb46f6c NFSD: Move fill_pre_wcc() and fill_post_wcc()
[ Upstream commit fcb5e3fa012351f3b96024c07bc44834c2478213 ]

These functions are related to file handle processing and have
nothing to do with XDR encoding or decoding. Also they are no longer
NFSv3-specific. As a clean-up, move their definitions to a more
appropriate location. WCC is also an NFSv3-specific term, so rename
them as general-purpose helpers.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:53 +01:00
Chuck Lever
124a3cdf27 Revert "nfsd: skip some unnecessary stats in the v4 case"
[ Upstream commit 58f258f65267542959487dbe8b5641754411843d ]

On the wire, I observed NFSv4 OPEN(CREATE) operations sometimes
returning a reasonable-looking value in the cinfo.before field and
zero in the cinfo.after field.

RFC 8881 Section 10.8.1 says:
> When a client is making changes to a given directory, it needs to
> determine whether there have been changes made to the directory by
> other clients.  It does this by using the change attribute as
> reported before and after the directory operation in the associated
> change_info4 value returned for the operation.

and

> ... The post-operation change
> value needs to be saved as the basis for future change_info4
> comparisons.

A good quality client implementation therefore saves the zero
cinfo.after value. During a subsequent OPEN operation, it will
receive a different non-zero value in the cinfo.before field for
that directory, and it will incorrectly believe the directory has
changed, triggering an undesirable directory cache invalidation.

There are filesystem types where fs_supports_change_attribute()
returns false, tmpfs being one. On NFSv4 mounts, this means the
fh_getattr() call site in fill_pre_wcc() and fill_post_wcc() is
never invoked. Subsequently, nfsd4_change_attribute() is invoked
with an uninitialized @stat argument.

In fill_pre_wcc(), @stat contains stale stack garbage, which is
then placed on the wire. In fill_post_wcc(), ->fh_post_wc is all
zeroes, so zero is placed on the wire. Both of these values are
meaningless.

This fix can be applied immediately to stable kernels. Once there
are more regression tests in this area, this optimization can be
attempted again.

Fixes: 428a23d2bf0c ("nfsd: skip some unnecessary stats in the v4 case")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:52 +01:00
Chuck Lever
57927de983 NFSD: Trace boot verifier resets
[ Upstream commit 75acacb6583df0b9328dc701d8eeea05af49b8b5 ]

According to commit bbf2f098838a ("nfsd: Reset the boot verifier on
all write I/O errors"), the Linux NFS server forces all clients to
resend pending unstable writes if any server-side write or commit
operation encounters an error (say, ENOSPC). This is a rare and
quite exceptional event that could require administrative recovery
action, so it should be made trace-able. Example trace event:

nfsd-938   [002]  7174.945558: nfsd_writeverf_reset: boot_time=        61cc920d xid=0xdcd62036 error=-28 new verifier=0x08aecc6142515904

[ cel: adjusted to apply to v5.10.y ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:52 +01:00
Chuck Lever
3b06528222 NFSD: Rename boot verifier functions
[ Upstream commit 3988a57885eeac05ef89f0ab4d7e47b52fbcf630 ]

Clean up: These functions handle what the specs call a write
verifier, which in the Linux NFS server implementation is now
divorced from the server's boot instance

[ cel: adjusted to apply to v5.10.y ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:52 +01:00
Chuck Lever
0c1abc4a75 NFSD: Clean up the nfsd_net::nfssvc_boot field
[ Upstream commit 91d2e9b56cf5c80f9efc530d494968369a8a0e0d ]

There are two boot-time fields in struct nfsd_net: one called
boot_time and one called nfssvc_boot. The latter is used only to
form write verifiers, but its documenting comment declares:

        /* Time of server startup */

Since commit 27c438f53e79 ("nfsd: Support the server resetting the
boot verifier"), this field can be reset at any time; it's no
longer tied to server restart. So that comment is stale.

Also, according to pahole, struct timespec64 is 16 bytes long on
x86_64. The nfssvc_boot field is used only to form a write verifier,
which is 8 bytes long.

Let's clarify this situation by manufacturing an 8-byte verifier
in nfs_reset_boot_verifier() and storing only that in struct
nfsd_net.

We're grabbing 128 bits of time, so compress all of those into a
64-bit verifier instead of throwing out the high-order bits.
In the future, the siphash_key can be re-used for other hashed
objects per-nfsd_net.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:52 +01:00
Chuck Lever
85f8d7896b NFSD: Write verifier might go backwards
[ Upstream commit cdc556600c0133575487cc69fb3128440b3c3e92 ]

When vfs_iter_write() starts to fail because a file system is full,
a bunch of writes can fail at once with ENOSPC. These writes
repeatedly invoke nfsd_reset_boot_verifier() in quick succession.

Ensure that the time it grabs doesn't go backwards due to an ntp
adjustment going on at the same time.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:52 +01:00
Trond Myklebust
8651e227f2 nfsd: Add a tracepoint for errors in nfsd4_clone_file_range()
[ Upstream commit a2f4c3fa4db94ba44d32a72201927cfd132a8e82 ]

Since a clone error commit can cause the boot verifier to change,
we should trace those errors.

Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
[ cel: Addressed a checkpatch.pl splat in fs/nfsd/vfs.h ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:52 +01:00
Chuck Lever
d4c52471e1 NFSD: De-duplicate net_generic(nf->nf_net, nfsd_net_id)
[ Upstream commit 2c445a0e72cb1fbfbdb7f9473c53556ee27c1d90 ]

Since this pointer is used repeatedly, move it to a stack variable.

[ cel: adjusted to apply to v5.10.y ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:52 +01:00
Chuck Lever
d60b181028 NFSD: De-duplicate net_generic(SVC_NET(rqstp), nfsd_net_id)
[ Upstream commit fb7622c2dbd1aa41133a8c73e1137b833c074519 ]

Since this pointer is used repeatedly, move it to a stack variable.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:52 +01:00
Chuck Lever
15dea95570 NFSD: Clean up nfsd_vfs_write()
[ Upstream commit 33388b3aefefd4d83764dab8038cb54068161a44 ]

The RWF_SYNC and !RWF_SYNC arms are now exactly alike except that
the RWF_SYNC arm resets the boot verifier twice in a row. Fix that
redundancy and de-duplicate the code.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:52 +01:00
Jeff Layton
f9c454e287 nfsd: Retry once in nfsd_open on an -EOPENSTALE return
[ Upstream commit 12bcbd40fd931472c7fc9cf3bfe66799ece93ed8 ]

If we get back -EOPENSTALE from an NFSv4 open, then we either got some
unhandled error or the inode we got back was not the same as the one
associated with the dentry.

We really have no recourse in that situation other than to retry the
open, and if it fails to just return nfserr_stale back to the client.

Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Lance Shelton <lance.shelton@hammerspace.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:52 +01:00
Jeff Layton
e6931a1dd7 nfsd: Add errno mapping for EREMOTEIO
[ Upstream commit a2694e51f60c5a18c7e43d1a9feaa46d7f153e65 ]

The NFS client can occasionally return EREMOTEIO when signalling issues
with the server.  ...map to NFSERR_IO.

Signed-off-by: Jeff Layton <jeff.layton@primarydata.com>
Signed-off-by: Lance Shelton <lance.shelton@hammerspace.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:52 +01:00
Peng Tao
40a15a91ce nfsd: map EBADF
[ Upstream commit b3d0db706c77d02055910fcfe2f6eb5155ff9d5e ]

Now that we have open file cache, it is possible that another client
deletes the file and DP will not know about it. Then IO to MDS would
fail with BADSTATEID and knfsd would start state recovery, which
should fail as well and then nfs read/write will fail with EBADF.
And it triggers a WARN() in nfserrno().

-----------[ cut here ]------------
WARNING: CPU: 0 PID: 13529 at fs/nfsd/nfsproc.c:758 nfserrno+0x58/0x70 [nfsd]()
nfsd: non-standard errno: -9
modules linked in: nfsv3 nfs_layout_flexfiles rpcsec_gss_krb5 nfsv4 dns_resolver nfs fscache ip6t_rpfilter ip6t_REJECT nf_reject_ipv6 xt_connt
pata_acpi floppy
CPU: 0 PID: 13529 Comm: nfsd Tainted: G        W       4.1.5-00307-g6e6579b #7
Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 09/30/2014
 0000000000000000 00000000464e6c9c ffff88079085fba8 ffffffff81789936
 0000000000000000 ffff88079085fc00 ffff88079085fbe8 ffffffff810a08ea
 ffff88079085fbe8 ffff88080f45c900 ffff88080f627d50 ffff880790c46a48
 all Trace:
 [<ffffffff81789936>] dump_stack+0x45/0x57
 [<ffffffff810a08ea>] warn_slowpath_common+0x8a/0xc0
 [<ffffffff810a0975>] warn_slowpath_fmt+0x55/0x70
 [<ffffffff81252908>] ? splice_direct_to_actor+0x148/0x230
 [<ffffffffa02fb8c0>] ? fsid_source+0x60/0x60 [nfsd]
 [<ffffffffa02f9918>] nfserrno+0x58/0x70 [nfsd]
 [<ffffffffa02fba57>] nfsd_finish_read+0x97/0xb0 [nfsd]
 [<ffffffffa02fc7a6>] nfsd_splice_read+0x76/0xa0 [nfsd]
 [<ffffffffa02fcca1>] nfsd_read+0xc1/0xd0 [nfsd]
 [<ffffffffa0233af2>] ? svc_tcp_adjust_wspace+0x12/0x30 [sunrpc]
 [<ffffffffa03073da>] nfsd3_proc_read+0xba/0x150 [nfsd]
 [<ffffffffa02f7a03>] nfsd_dispatch+0xc3/0x210 [nfsd]
 [<ffffffffa0233af2>] ? svc_tcp_adjust_wspace+0x12/0x30 [sunrpc]
 [<ffffffffa0232913>] svc_process_common+0x453/0x6f0 [sunrpc]
 [<ffffffffa0232cc3>] svc_process+0x113/0x1b0 [sunrpc]
 [<ffffffffa02f740f>] nfsd+0xff/0x170 [nfsd]
 [<ffffffffa02f7310>] ? nfsd_destroy+0x80/0x80 [nfsd]
 [<ffffffff810bf3a8>] kthread+0xd8/0xf0
 [<ffffffff810bf2d0>] ? kthread_create_on_node+0x1b0/0x1b0
 [<ffffffff817912a2>] ret_from_fork+0x42/0x70
 [<ffffffff810bf2d0>] ? kthread_create_on_node+0x1b0/0x1b0

Signed-off-by: Peng Tao <tao.peng@primarydata.com>
Signed-off-by: Lance Shelton <lance.shelton@hammerspace.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:52 +01:00
Chuck Lever
2543173ec6 NFSD: Fix zero-length NFSv3 WRITEs
[ Upstream commit 6a2f774424bfdcc2df3e17de0cefe74a4269cad5 ]

The Linux NFS server currently responds to a zero-length NFSv3 WRITE
request with NFS3ERR_IO. It responds to a zero-length NFSv4 WRITE
with NFS4_OK and count of zero.

RFC 1813 says of the WRITE procedure's @count argument:

count
         The number of bytes of data to be written. If count is
         0, the WRITE will succeed and return a count of 0,
         barring errors due to permissions checking.

RFC 8881 has similar language for NFSv4, though NFSv4 removed the
explicit @count argument because that value is already contained in
the opaque payload array.

The synthetic client pynfs's WRT4 and WRT15 tests do emit zero-
length WRITEs to exercise this spec requirement. Commit fdec6114ee1f
("nfsd4: zero-length WRITE should succeed") addressed the same
problem there with the same fix.

But interestingly the Linux NFS client does not appear to emit zero-
length WRITEs, instead squelching them. I'm not aware of a test that
can generate such WRITEs for NFSv3, so I wrote a naive C program to
generate a zero-length WRITE and test this fix.

Fixes: 8154ef2776aa ("NFSD: Clean up legacy NFS WRITE argument XDR decoders")
Reported-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Cc: stable@vger.kernel.org
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:52 +01:00
Vasily Averin
065246aa5b nfsd4: add refcount for nfsd4_blocked_lock
[ Upstream commit 47446d74f1707049067fee038507cdffda805631 ]

nbl allocated in nfsd4_lock can be released by a several ways:
directly in nfsd4_lock(), via nfs4_laundromat(), via another nfs
command RELEASE_LOCKOWNER or via nfsd4_callback.
This structure should be refcounted to be used and released correctly
in all these cases.

Refcount is initialized to 1 during allocation and is incremented
when nbl is added into nbl_list/nbl_lru lists.

Usually nbl is linked into both lists together, so only one refcount
is used for both lists.

However nfsd4_lock() should keep in mind that nbl can be present
in one of lists only. This can happen if nbl was handled already
by nfs4_laundromat/nfsd4_callback/etc.

Refcount is decremented if vfs_lock_file() returns FILE_LOCK_DEFERRED,
because nbl can be handled already by nfs4_laundromat/nfsd4_callback/etc.

Refcount is not changed in find_blocked_lock() because of it reuses counter
released after removing nbl from lists.

Signed-off-by: Vasily Averin <vvs@virtuozzo.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>
2024-11-19 12:27:52 +01:00
J. Bruce Fields
26d8c7f66c nfs: block notification on fs with its own ->lock
[ Upstream commit 40595cdc93edf4110c0f0c0b06f8d82008f23929 ]

NFSv4.1 supports an optional lock notification feature which notifies
the client when a lock comes available.  (Normally NFSv4 clients just
poll for locks if necessary.)  To make that work, we need to request a
blocking lock from the filesystem.

We turned that off for NFS in commit f657f8eef3ff ("nfs: don't atempt
blocking locks on nfs reexports") [sic] because it actually blocks the
nfsd thread while waiting for the lock.

Thanks to Vasily Averin for pointing out that NFS isn't the only
filesystem with that problem.

Any filesystem that leaves ->lock NULL will use posix_lock_file(), which
does the right thing.  Simplest is just to assume that any filesystem
that defines its own ->lock is not safe to request a blocking lock from.

So, this patch mostly reverts commit f657f8eef3ff ("nfs: don't atempt
blocking locks on nfs reexports") [sic] and commit b840be2f00c0 ("lockd:
don't attempt blocking locks on nfs reexports"), and instead uses a
check of ->lock (Vasily's suggestion) to decide whether to support
blocking lock notifications on a given filesystem.  Also add a little
documentation.

Perhaps someday we could add back an export flag later to allow
filesystems with "good" ->lock methods to support blocking lock
notifications.

Reported-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: J. Bruce Fields <bfields@redhat.com>
[ cel: Description rewritten to address checkpatch nits ]
[ cel: Fixed warning when SUNRPC debugging is disabled ]
[ cel: Fixed NULL check ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:52 +01:00
Chuck Lever
4555855ccc NFSD: De-duplicate nfsd4_decode_bitmap4()
[ Upstream commit cd2e999c7c394ae916d8be741418b3c6c1dddea8 ]

Clean up. Trond points out that xdr_stream_decode_uint32_array()
does the same thing as nfsd4_decode_bitmap4().

Suggested-by: Trond Myklebust <trondmy@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:51 +01:00
J. Bruce Fields
80b0c59bf7 nfsd: improve stateid access bitmask documentation
[ Upstream commit 3dcd1d8aab00c5d3a0a3725253c86440b1a0f5a7 ]

The use of the bitmaps is confusing.  Add a cross-reference to make it
easier to find the existing comment.  Add an updated reference with URL
to make it quicker to look up.  And a bit more editorializing about the
value of this.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:51 +01:00
Chuck Lever
0b68d96667 NFSD: Combine XDR error tracepoints
[ Upstream commit 70e94d757b3e1f46486d573729d84c8955c81dce ]

Clean up: The garbage_args and cant_encode tracepoints report the
same information as each other, so combine them into a single
tracepoint class to reduce code duplication and slightly reduce the
size of trace.o.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:51 +01:00
NeilBrown
fefe2352c2 NFSD: simplify per-net file cache management
[ Upstream commit 1463b38e7cf34d4cc60f41daff459ad807b2e408 ]

We currently have a 'laundrette' for closing cached files - a different
work-item for each network-namespace.

These 'laundrettes' (aka struct nfsd_fcache_disposal) are currently on a
list, and are freed using rcu.

The list is not necessary as we have a per-namespace structure (struct
nfsd_net) which can hold a link to the nfsd_fcache_disposal.
The use of kfree_rcu is also unnecessary as the cache is cleaned of all
files associated with a given namespace, and no new files can be added,
before the nfsd_fcache_disposal is freed.

So add a '->fcache_disposal' link to nfsd_net, and discard the list
management and rcu usage.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:51 +01:00
Jiapeng Chong
f6eb876315 NFSD: Fix inconsistent indenting
[ Upstream commit 1e37d0e5bda45881eea1bec4b812def72c7d4aea ]

Eliminate the follow smatch warning:

fs/nfsd/nfs4xdr.c:4766 nfsd4_encode_read_plus_hole() warn: inconsistent
indenting.

Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:51 +01:00
Chuck Lever
ee471f1758 NFSD: Remove be32_to_cpu() from DRC hash function
[ Upstream commit 7578b2f628db27281d3165af0aa862311883a858 ]

Commit 7142b98d9fd7 ("nfsd: Clean up drc cache in preparation for
global spinlock elimination"), billed as a clean-up, added
be32_to_cpu() to the DRC hash function without explanation. That
commit removed two comments that state that byte-swapping in the
hash function is unnecessary without explaining whether there was
a need for that change.

On some Intel CPUs, the swab32 instruction is known to cause a CPU
pipeline stall. be32_to_cpu() does not add extra randomness, since
the hash multiplication is done /before/ shifting to the high-order
bits of the result.

As a micro-optimization, remove the unnecessary transform from the
DRC hash function.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:51 +01:00
NeilBrown
d69c68e4b0 NFSD: simplify locking for network notifier.
[ Upstream commit d057cfec4940ce6eeffa22b4a71dec203b06cd55 ]

nfsd currently maintains an open-coded read/write semaphore (refcount
and wait queue) for each network namespace to ensure the nfs service
isn't shut down while the notifier is running.

This is excessive.  As there is unlikely to be contention between
notifiers and they run without sleeping, a single spinlock is sufficient
to avoid problems.

Signed-off-by: NeilBrown <neilb@suse.de>
[ cel: ensure nfsd_notifier_lock is static ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:50 +01:00
NeilBrown
ab30e7bffb SUNRPC: discard svo_setup and rename svc_set_num_threads_sync()
[ Upstream commit 3ebdbe5203a874614819700d3f470724cb803709 ]

The ->svo_setup callback serves no purpose.  It is always called from
within the same module that chooses which callback is needed.  So
discard it and call the relevant function directly.

Now that svc_set_num_threads() is no longer used remove it and rename
svc_set_num_threads_sync() to remove the "_sync" suffix.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:50 +01:00
NeilBrown
873ea429f8 NFSD: Make it possible to use svc_set_num_threads_sync
[ Upstream commit 3409e4f1e8f239f0ed81be0b068ecf4e73e2e826 ]

nfsd cannot currently use svc_set_num_threads_sync.  It instead
uses svc_set_num_threads which does *not* wait for threads to all
exit, and has a separate mechanism (nfsd_shutdown_complete) to wait
for completion.

The reason that nfsd is unlike other services is that nfsd threads can
exit separately from svc_set_num_threads being called - they die on
receipt of SIGKILL.  Also, when the last thread exits, the service must
be shut down (sockets closed).

For this, the nfsd_mutex needs to be taken, and as that mutex needs to
be held while svc_set_num_threads is called, the one cannot wait for
the other.

This patch changes the nfsd thread so that it can drop the ref on the
service without blocking on nfsd_mutex, so that svc_set_num_threads_sync
can be used:
 - if it can drop a non-last reference, it does that.  This does not
   trigger shutdown and does not require a mutex.  This will likely
   happen for all but the last thread signalled, and for all threads
   being shut down by nfsd_shutdown_threads()
 - if it can get the mutex without blocking (trylock), it does that
   and then drops the reference.  This will likely happen for the
   last thread killed by SIGKILL
 - Otherwise there might be an unrelated task holding the mutex,
   possibly in another network namespace, or nfsd_shutdown_threads()
   might be just about to get a reference on the service, after which
   we can drop ours safely.
   We cannot conveniently get wakeup notifications on these events,
   and we are unlikely to need to, so we sleep briefly and check again.

With this we can discard nfsd_shutdown_complete and
nfsd_complete_shutdown(), and switch to svc_set_num_threads_sync.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:50 +01:00
NeilBrown
92793de4f5 NFSD: narrow nfsd_mutex protection in nfsd thread
[ Upstream commit 9d3792aefdcda71d20c2b1ecc589c17ae71eb523 ]

There is nothing happening in the start of nfsd() that requires
protection by the mutex, so don't take it until shutting down the thread
- which does still require protection - but only for nfsd_put().

Signed-off-by: NeilBrown <neilb@suse.de>
[ cel: address merge conflict with fd2468fa1301 ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:50 +01:00
NeilBrown
f1f6cafeb9 SUNRPC: use sv_lock to protect updates to sv_nrthreads.
[ Upstream commit 2a36395fac3b72771f87c3ee4387e3a96d85a7cc ]

Using sv_lock means we don't need to hold the service mutex over these
updates.

In particular,  svc_exit_thread() no longer requires synchronisation, so
threads can exit asynchronously.

Note that we could use an atomic_t, but as there are many more read
sites than writes, that would add unnecessary noise to the code.
Some reads are already racy, and there is no need for them to not be.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:50 +01:00
NeilBrown
37d53c0889 nfsd: make nfsd_stats.th_cnt atomic_t
[ Upstream commit 9b6c8c9bebccd5fb785c306b948c08874a88874d ]

This allows us to move the updates for th_cnt out of the mutex.
This is a step towards reducing mutex coverage in nfsd().

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:50 +01:00
NeilBrown
58232d691d SUNRPC: stop using ->sv_nrthreads as a refcount
[ Upstream commit ec52361df99b490f6af412b046df9799b92c1050 ]

The use of sv_nrthreads as a general refcount results in clumsy code, as
is seen by various comments needed to explain the situation.

This patch introduces a 'struct kref' and uses that for reference
counting, leaving sv_nrthreads to be a pure count of threads.  The kref
is managed particularly in svc_get() and svc_put(), and also nfsd_put();

svc_destroy() now takes a pointer to the embedded kref, rather than to
the serv.

nfsd allows the svc_serv to exist with ->sv_nrhtreads being zero.  This
happens when a transport is created before the first thread is started.
To support this, a 'keep_active' flag is introduced which holds a ref on
the svc_serv.  This is set when any listening socket is successfully
added (unless there are running threads), and cleared when the number of
threads is set.  So when the last thread exits, the nfs_serv will be
destroyed.
The use of 'keep_active' replaces previous code which checked if there
were any permanent sockets.

We no longer clear ->rq_server when nfsd() exits.  This was done
to prevent svc_exit_thread() from calling svc_destroy().
Instead we take an extra reference to the svc_serv to prevent
svc_destroy() from being called.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:50 +01:00
NeilBrown
a1ed765f29 SUNRPC/NFSD: clean up get/put functions.
[ Upstream commit 8c62d12740a1450d2e8456d5747f440e10db281a ]

svc_destroy() is poorly named - it doesn't necessarily destroy the svc,
it might just reduce the ref count.
nfsd_destroy() is poorly named for the same reason.

This patch:
 - removes the refcount functionality from svc_destroy(), moving it to
   a new svc_put().  Almost all previous callers of svc_destroy() now
   call svc_put().
 - renames nfsd_destroy() to nfsd_put() and improves the code, using
   the new svc_destroy() rather than svc_put()
 - removes a few comments that explain the important for balanced
   get/put calls.  This should be obvious.

The only non-trivial part of this is that svc_destroy() would call
svc_sock_update() on a non-final decrement.  It can no longer do that,
and svc_put() isn't really a good place of it.  This call is now made
from svc_exit_thread() which seems like a good place.  This makes the
call *before* sv_nrthreads is decremented rather than after.  This
is not particularly important as the call just sets a flag which
causes sv_nrthreads set be checked later.  A subsequent patch will
improve the ordering.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:50 +01:00
NeilBrown
d5ed87db21 NFSD: handle errors better in write_ports_addfd()
[ Upstream commit 89b24336f03a8ba560e96b0c47a8434a7fa48e3c ]

If write_ports_add() fails, we shouldn't destroy the serv, unless we had
only just created it.  So if there are any permanent sockets already
attached, leave the serv in place.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:50 +01:00
Chuck Lever
853a7127ee NFSD: Fix sparse warning
[ Upstream commit c2f1c4bd20621175c581f298b4943df0cffbd841 ]

/home/cel/src/linux/linux/fs/nfsd/nfs4proc.c:1539:24: warning: incorrect type in assignment (different base types)
/home/cel/src/linux/linux/fs/nfsd/nfs4proc.c:1539:24:    expected restricted __be32 [usertype] status
/home/cel/src/linux/linux/fs/nfsd/nfs4proc.c:1539:24:    got int

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:50 +01:00
Eric W. Biederman
83327c859e exit: Rename module_put_and_exit to module_put_and_kthread_exit
[ Upstream commit ca3574bd653aba234a4b31955f2778947403be16 ]

Update module_put_and_exit to call kthread_exit instead of do_exit.

Change the name to reflect this change in functionality.  All of the
users of module_put_and_exit are causing the current kthread to exit
so this change makes it clear what is happening.  There is no
functional change.

Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-11-19 12:27:50 +01:00