Commit Graph

1250806 Commits

Author SHA1 Message Date
Chuck Lever
773f6c5b72 svcrdma: Prevent a UAF in svc_rdma_send()
In some error flow cases, svc_rdma_wc_send() releases @ctxt. Copy
the sc_cid field in @ctxt to a stack variable in order to guarantee
that the value is available after the ib_post_send() call.

In case the new comment looks a little strange, this will be done
with at least one more field in a subsequent patch.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:27 -05:00
Chuck Lever
5b9a85899c svcrdma: Fix SQ wake-ups
Ensure there is a wake-up when increasing sc_sq_avail.

Likewise, if a wake-up is done, sc_sq_avail needs to be updated,
otherwise the wait_event() conditional is never going to be met.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:27 -05:00
Chuck Lever
2da0f610e7 svcrdma: Increase the per-transport rw_ctx count
rdma_rw_mr_factor() returns the smallest number of MRs needed to
move a particular number of pages. svcrdma currently asks for the
number of MRs needed to move RPCSVC_MAXPAGES (a little over one
megabyte), as that is the number of pages in the largest r/wsize
the server supports.

This call assumes that the client's NIC can bundle a full one
megabyte payload in a single rdma_segment. In fact, most NICs cannot
handle a full megabyte with a single rkey / rdma_segment. Clients
will typically split even a single Read chunk into many segments.

The server needs one MR to read each rdma_segment in a Read chunk,
and thus each one needs an rw_ctx.

svcrdma has been vastly underestimating the number of rw_ctxs needed
to handle 64 RPC requests with large Read chunks using small
rdma_segments.

Unfortunately there doesn't seem to be a good way to estimate this
number without knowing the client NIC's capabilities. Even then,
the client RPC/RDMA implementation is still free to split a chunk
into smaller segments (for example, it might be using physical
registration, which needs an rdma_segment per page).

The best we can do for now is choose a number that will guarantee
forward progress in the worst case (one page per segment).

At some later point, we could add some mechanisms to make this
much less of a problem:
- Add a core API to add more rw_ctxs to an already-established QP
- svcrdma could treat rw_ctx exhaustion as a temporary error and
  try again
- Limit the number of Reads in flight

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:26 -05:00
Chuck Lever
4c8c0fa0d3 svcrdma: Update max_send_sges after QP is created
rdma_create_qp() can modify cap.max_send_sges. Copy the new value
to the svcrdma transport so it is bound by the new limit instead
of the requested one.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:26 -05:00
Chuck Lever
5485d6ddfc svcrdma: Report CQ depths in debugging output
Check that svc_rdma_accept() is allocating an appropriate number of
CQEs.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:25 -05:00
Chuck Lever
e67792cc96 svcrdma: Reserve an extra WQE for ib_drain_rq()
Do as other ULPs already do: ensure there is an extra Receive WQE
reserved for the tear-down drain WR. I haven't heard reports of
problems but it can't hurt.

Note that rq_depth is used to compute the Send Queue depth as well,
so this fix should affect both the SQ and RQ.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:25 -05:00
Jeff Layton
c8004c1ca4 MAINTAINERS: add Alex Aring as Reviewer for file locking code
Alex helps co-maintain the DLM code and did some recent work to fix up
how lockd and GFS2 work together. Add him as a Reviewer for file locking
changes.

Acked-by: Alexander Aring <aahringo@redhat.com>
Acked-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:25 -05:00
Kunwu Chan
649e58d593 nfsd: Simplify the allocation of slab caches in nfsd4_init_slabs
Use the new KMEM_CACHE() macro instead of direct kmem_cache_create
to simplify the creation of SLAB caches.
Make the code cleaner and more readable.

Signed-off-by: Kunwu Chan <chentao@kylinos.cn>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:24 -05:00
Kunwu Chan
192d80cdcb nfsd: Simplify the allocation of slab caches in nfsd_drc_slab_create
Use the new KMEM_CACHE() macro instead of direct kmem_cache_create
to simplify the creation of SLAB caches.
And change cache name from 'nfsd_drc' to 'nfsd_cacherep'.

Signed-off-by: Kunwu Chan <chentao@kylinos.cn>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:24 -05:00
Kunwu Chan
2f74991a49 nfsd: Simplify the allocation of slab caches in nfsd_file_cache_init
Use the new KMEM_CACHE() macro instead of direct kmem_cache_create
to simplify the creation of SLAB caches.

Signed-off-by: Kunwu Chan <chentao@kylinos.cn>
Acked-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:23 -05:00
Kunwu Chan
10bcc2f1c8 nfsd: Simplify the allocation of slab caches in nfsd4_init_pnfs
commit 0a31bd5f2b ("KMEM_CACHE(): simplify slab cache creation")
introduces a new macro.
Use the new KMEM_CACHE() macro instead of direct kmem_cache_create
to simplify the creation of SLAB caches.

Signed-off-by: Kunwu Chan <chentao@kylinos.cn>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:23 -05:00
NeilBrown
05eda6e757 nfsd: don't call locks_release_private() twice concurrently
It is possible for free_blocked_lock() to be called twice concurrently,
once from nfsd4_lock() and once from nfsd4_release_lockowner() calling
remove_blocked_locks().  This is why a kref was added.

It is perfectly safe for locks_delete_block() and kref_put() to be
called in parallel as they use locking or atomicity respectively as
protection.  However locks_release_private() has no locking.  It is
safe for it to be called twice sequentially, but not concurrently.

This patch moves that call from free_blocked_lock() where it could race
with itself, to free_nbl() where it cannot.  This will slightly delay
the freeing of private info or release of the owner - but not by much.
It is arguably more natural for this freeing to happen in free_nbl()
where the structure itself is freed.

This bug was found by code inspection - it has not been seen in practice.

Fixes: 47446d74f1 ("nfsd4: add refcount for nfsd4_blocked_lock")
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:23 -05:00
NeilBrown
1e33e1414b nfsd: allow layout state to be admin-revoked.
When there is layout state on a filesystem that is being "unlocked" that
is now revoked, which involves closing the nfsd_file and releasing the
vfs lease.

To avoid races, ->ls_file can now be accessed either:
 - under ->fi_lock for the state's sc_file or
 - under rcu_read_lock() if nfsd_file_get() is used.
To support this, ->fence_client and nfsd4_cb_layout_fail() now take a
second argument being the nfsd_file.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:22 -05:00
NeilBrown
06efa66750 nfsd: allow delegation state ids to be revoked and then freed
Revoking state through 'unlock_filesystem' now revokes any delegation
states found.  When the stateids are then freed by the client, the
revoked stateids will be cleaned up correctly.

As there is already support for revoking delegations, we build on that
for admin-revoking.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:22 -05:00
NeilBrown
39657c7406 nfsd: allow open state ids to be revoked and then freed
Revoking state through 'unlock_filesystem' now revokes any open states
found.  When the stateids are then freed by the client, the revoked
stateids will be cleaned up correctly.

Possibly the related lock states should be revoked too, but a
subsequent patch will do that for all lock state on the superblock.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:21 -05:00
NeilBrown
1c13bf9f2e nfsd: allow lock state ids to be revoked and then freed
Revoking state through 'unlock_filesystem' now revokes any lock states
found.  When the stateids are then freed by the client, the revoked
stateids will be cleaned up correctly.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:21 -05:00
NeilBrown
d688d8585e nfsd: allow admin-revoked NFSv4.0 state to be freed.
For NFSv4.1 and later the client easily discovers if there is any
admin-revoked state and will then find and explicitly free it.

For NFSv4.0 there is no such mechanism.  The client can only find that
state is admin-revoked if it tries to use that state, and there is no
way for it to explicitly free the state.  So the server must hold on to
the stateid (at least) for an indefinite amount of time.  A
RELEASE_LOCKOWNER request might justify forgetting some of these
stateids, as would the whole clients lease lapsing, but these are not
reliable.

This patch takes two approaches.

Whenever a client uses an revoked stateid, that stateid is then
discarded and will not be recognised again.  This might confuse a client
which expect to get NFS4ERR_ADMIN_REVOKED consistently once it get it at
all, but should mostly work.  Hopefully one error will lead to other
resources being closed (e.g.  process exits), which will result in more
stateid being freed when a CLOSE attempt gets NFS4ERR_ADMIN_REVOKED.

Also, any admin-revoked stateids that have been that way for more than
one lease time are periodically revoke.

No actual freeing of state happens in this patch.  That will come in
future patches which handle the different sorts of revoked state.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:21 -05:00
NeilBrown
11b2cfbf6c nfsd: report in /proc/fs/nfsd/clients/*/states when state is admin-revoke
Add "admin-revoked" to the status information for any states that have
been admin-revoked.  This can be useful for confirming correct
behaviour.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:20 -05:00
NeilBrown
39e1be6471 nfsd: allow state with no file to appear in /proc/fs/nfsd/clients/*/states
Change the "show" functions to show some content even if a file cannot
be found.  This is the case for admin-revoked state.
This is primarily useful for debugging - to ensure states are being
removed eventually.

So change several seq_printf() to seq_puts().  Some of these are needed
to keep checkpatch happy.  Others were done for consistency.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:20 -05:00
NeilBrown
1ac3629bf0 nfsd: prepare for supporting admin-revocation of state
The NFSv4 protocol allows state to be revoked by the admin and has error
codes which allow this to be communicated to the client.

This patch
 - introduces a new state-id status SC_STATUS_ADMIN_REVOKED
   which can be set on open, lock, or delegation state.
 - reports NFS4ERR_ADMIN_REVOKED when these are accessed
 - introduces a per-client counter of these states and returns
   SEQ4_STATUS_ADMIN_STATE_REVOKED when the counter is not zero.
   Decrements this when freeing any admin-revoked state.
 - introduces stub code to find all interesting states for a given
   superblock so they can be revoked via the 'unlock_filesystem'
   file in /proc/fs/nfsd/
   No actual states are handled yet.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:19 -05:00
NeilBrown
3f29cc82a8 nfsd: split sc_status out of sc_type
sc_type identifies the type of a state - open, lock, deleg, layout - and
also the status of a state - closed or revoked.

This is a bit untidy and could get worse when "admin-revoked" states are
added.  So clean it up.

With this patch, the type is now all that is stored in sc_type.  This is
zero when the state is first added to ->cl_stateids (causing it to be
ignored), and is then set appropriately once it is fully initialised.
It is set under ->cl_lock to ensure atomicity w.r.t lookup.  It is now
never cleared.

sc_type is still a bit-set even though at most one bit is set.  This allows
lookup functions to be given a bitmap of acceptable types.

sc_type is now an unsigned short rather than char.  There is no value in
restricting to just 8 bits.

All the constants now start SC_TYPE_ matching the field in which they
are stored.  Keeping the existing names and ensuring clear separation
from non-type flags would have required something like
NFS4_STID_TYPE_CLOSED which is cumbersome.  The "NFS4" prefix is
redundant was they only appear in NFS4 code, so remove that and change
STID to SC to match the field.

The status is stored in a separate unsigned short named "sc_status".  It
has two flags: SC_STATUS_CLOSED and SC_STATUS_REVOKED.
CLOSED combines NFS4_CLOSED_STID, NFS4_CLOSED_DELEG_STID, and is used
for SC_TYPE_LOCK and SC_TYPE_LAYOUT instead of setting the sc_type to zero.
These flags are only ever set, never cleared.
For deleg stateids they are set under the global state_lock.
For open and lock stateids they are set under ->cl_lock.
For layout stateids they are set under ->ls_lock

nfs4_unhash_stid() has been removed, and we never set sc_type = 0.  This
was only used for LOCK and LAYOUT stids and they now use
SC_STATUS_CLOSED.

Also TRACE_DEFINE_NUM() calls for the various STID #define have been
removed because these things are not enums, and so that call is
incorrect.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:19 -05:00
NeilBrown
83e733161f nfsd: avoid race after unhash_delegation_locked()
NFS4_CLOSED_DELEG_STID and NFS4_REVOKED_DELEG_STID are similar in
purpose.
REVOKED is used for NFSv4.1 states which have been revoked because the
lease has expired.  CLOSED is used in other cases.
The difference has two practical effects.
1/ REVOKED states are on the ->cl_revoked list
2/ REVOKED states result in nfserr_deleg_revoked from
   nfsd4_verify_open_stid() and nfsd4_validate_stateid while
   CLOSED states result in nfserr_bad_stid.

Currently a state that is being revoked is first set to "CLOSED" in
unhash_delegation_locked(), then possibly to "REVOKED" in
revoke_delegation(), at which point it is added to the cl_revoked list.

It is possible that a stateid test could see the CLOSED state
which really should be REVOKED, and so return the wrong error code.  So
it is safest to remove this window of inconsistency.

With this patch, unhash_delegation_locked() always sets the state
correctly, and revoke_delegation() no longer changes the state.

Also remove a redundant test on minorversion when
NFS4_REVOKED_DELEG_STID is seen - it can only be seen when minorversion
is non-zero.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:19 -05:00
NeilBrown
c6540026df nfsd: don't call functions with side-effecting inside WARN_ON()
Code like:

    WARN_ON(foo())

looks like an assertion and might not be expected to have any side
effects.
When testing if a function with side-effects fails a construct like

    if (foo())
       WARN_ON(1);

makes the intent more obvious.

nfsd has several WARN_ON calls where the test has side effects, so it
would be good to change them.  These cases don't really need the
WARN_ON.  They have never failed in 8 years of usage so let's just
remove the WARN_ON wrapper.

Suggested-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:18 -05:00
NeilBrown
779457285a nfsd: hold ->cl_lock for hash_delegation_locked()
The protocol for creating a new state in nfsd is to allocate the state
leaving it largely uninitialised, add that state to the ->cl_stateids
idr so as to reserve a state-id, then complete initialisation of the
state and only set ->sc_type to non-zero once the state is fully
initialised.

If a state is found in the idr with ->sc_type == 0, it is ignored.
The ->cl_lock lock is used to avoid races - it is held while checking
sc_type during lookup, and held when a non-zero value is stored in
->sc_type.

... except... hash_delegation_locked() finalises the initialisation of a
delegation state, but does NOT hold ->cl_lock.

So this patch takes ->cl_lock at the appropriate time w.r.t other locks,
and so ensures there are no races (which are extremely unlikely in any
case).
As ->fi_lock is often taken when ->cl_lock is held, we need to take
->cl_lock first of those two.
Currently ->cl_lock and state_lock are never both taken at the same time.
We need both for this patch so an arbitrary choice is needed concerning
which to take first.  As state_lock is more global, it might be more
contended, so take it first.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:18 -05:00
NeilBrown
6b4ca49dc3 nfsd: remove stale comment in nfs4_show_deleg()
As we do now support write delegations, this comment is unhelpful and
misleading.

Reported-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:17 -05:00
Chuck Lever
e3179e443c NFSD: Remove redundant cb_seq_status initialization
As far as I can see, setting cb_seq_status in nfsd4_init_cb() is
superfluous because it is set again in nfsd4_cb_prepare().

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:17 -05:00
Chuck Lever
3f0ba61405 SUNRPC: Remove stale comments
bc_close() and bc_destroy now do something, so the comments are
no longer correct. Commit 6221f1d9b6 ("SUNRPC: Fix backchannel
RPC soft lockups") should have removed these.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:16 -05:00
Chuck Lever
84ebf02d75 NFSD: Remove BUG_ON in nfsd4_process_cb_update()
Don't kill the kworker thread, and don't panic while cl_lock is
held. There's no need for scorching the earth here.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:16 -05:00
Chuck Lever
112bdd597d NFSD: Replace comment with lockdep assertion
Convert a code comment into a real assertion.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:16 -05:00
Chuck Lever
627fb18302 NFSD: Remove unused @reason argument
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:15 -05:00
Chuck Lever
bc4a27e915 SUNRPC: Remove EXPORT_SYMBOL_GPL for svc_process_bc()
svc_process_bc(), previously known as bc_svc_process(), was
added in commit 4d6bbb6233 ("nfs41: Backchannel bc_svc_process()")
but there has never been a call site outside of the sunrpc.ko
module.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:15 -05:00
Chuck Lever
9a026aec88 NFSD: Add callback operation lifetime trace points
Help observe the flow of callback operations.

bc_shutdown() records exactly when the backchannel RPC client is
destroyed and cl_cb_client is replaced with NULL.

Examples include:

         nfsd-955   [004]   650.013997: nfsd_cb_queue:        addr=192.168.122.6:0 client 65b3c5b8:f541f749 cb=0xffff8881134b02f8 (first try)
kworker/u21:4-497   [004]   650.014050: nfsd_cb_seq_status:   task:00000001@00000001 sessionid=65b3c5b8:f541f749:00000001:00000000 tk_status=-107 seq_status=1
kworker/u21:4-497   [004]   650.014051: nfsd_cb_restart:      addr=192.168.122.6:0 client 65b3c5b8:f541f749 cb=0xffff88810e39f400 (first try)
kworker/u21:4-497   [004]   650.014066: nfsd_cb_queue:        addr=192.168.122.6:0 client 65b3c5b8:f541f749 cb=0xffff88810e39f400 (need restart)


kworker/u16:0-10    [006]   650.065750: nfsd_cb_start:        addr=192.168.122.6:0 client 65b3c5b8:f541f749 state=UNKNOWN
kworker/u16:0-10    [006]   650.065752: nfsd_cb_bc_update:    addr=192.168.122.6:0 client 65b3c5b8:f541f749 cb=0xffff8881134b02f8 (first try)
kworker/u16:0-10    [006]   650.065754: nfsd_cb_bc_shutdown:  addr=192.168.122.6:0 client 65b3c5b8:f541f749 cb=0xffff8881134b02f8 (first try)
kworker/u16:0-10    [006]   650.065810: nfsd_cb_new_state:    addr=192.168.122.6:0 client 65b3c5b8:f541f749 state=DOWN

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:15 -05:00
Chuck Lever
a7cdf065e1 NFSD: Rename nfsd_cb_state trace point
Make it clear where backchannel state is updated.

Example trace point output:

kworker/u16:0-10    [006]  2800.080404: nfsd_cb_new_state:    addr=192.168.122.6:0 client 65b3c5b8:f541f749 state=UP
         nfsd-940   [003]  2800.478368: nfsd_cb_new_state:    addr=192.168.122.6:0 client 65b3c5b8:f541f749 state=UNKNOWN
kworker/u16:0-10    [003]  2800.478828: nfsd_cb_new_state:    addr=192.168.122.6:0 client 65b3c5b8:f541f749 state=DOWN

kworker/u16:0-10    [005]  2802.039724: nfsd_cb_start:        addr=192.168.122.6:0 client 65b3c5b8:f541f749 state=UP
kworker/u16:0-10    [005]  2810.611452: nfsd_cb_start:        addr=192.168.122.6:0 client 65b3c5b8:f541f749 state=FAULT
kworker/u16:0-10    [005]  2810.616832: nfsd_cb_start:        addr=192.168.122.6:0 client 65b3c5b8:f541f749 state=UNKNOWN
kworker/u16:0-10    [005]  2810.616931: nfsd_cb_start:        addr=192.168.122.6:0 client 65b3c5b8:f541f749 state=DOWN

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:14 -05:00
Chuck Lever
8626664c87 NFSD: Replace dprintks in nfsd4_cb_sequence_done()
Improve observability of backchannel session operation.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:14 -05:00
Chuck Lever
f52f1975b1 NFSD: Add nfsd_seq4_status trace event
Add a trace point that records SEQ4_STATUS flags returned in an
NFSv4.1 SEQUENCE response. SEQ4_STATUS flags report backchannel
issues and changes to lease state to clients. Knowing what the
server is reporting to clients is useful for debugging both
configuration and operational issues in real time.

For example, upcoming patches will enable server administrators to
revoke parts of a client's lease; that revocation is indicated to
the client when a subsequent SEQUENCE operation has one or more
SEQ4_STATUS flags that are set.

Sample trace records:

nfsd-927   [006]   615.581821: nfsd_seq4_status:     xid=0x095ded07 sessionid=65a032c3:b7845faf:00000001:00000000 status_flags=BACKCHANNEL_FAULT
nfsd-927   [006]   615.588043: nfsd_seq4_status:     xid=0x0a5ded07 sessionid=65a032c3:b7845faf:00000001:00000000 status_flags=BACKCHANNEL_FAULT
nfsd-928   [003]   615.588448: nfsd_seq4_status:     xid=0x0b5ded07 sessionid=65a032c3:b7845faf:00000001:00000000 status_flags=BACKCHANNEL_FAULT

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:13 -05:00
Chuck Lever
43b02dba11 NFSD: Retransmit callbacks after client reconnects
NFSv4.1 clients assume that if they disconnect, that will force the
server to resend pending callback operations once a fresh connection
has been established.

Turns out NFSD has not been resending after reconnect.

Fixes: 7ba6cad6c8 ("nfsd: New helper nfsd4_cb_sequence_done() for processing more cb errors")
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:13 -05:00
Chuck Lever
c1ccfcf1a9 NFSD: Reschedule CB operations when backchannel rpc_clnt is shut down
As part of managing a client disconnect, NFSD closes down and
replaces the backchannel rpc_clnt.

If a callback operation is pending when the backchannel rpc_clnt is
shut down, currently nfsd4_run_cb_work() just discards that
callback. But there are multiple cases to deal with here:

 o The client's lease is getting destroyed. Throw the CB away.

 o The client disconnected. It might be forcing a retransmit of
   CB operations, or it could have disconnected for other reasons.
   Reschedule the CB so it is retransmitted when the client
   reconnects.

Since callback operations can now be rescheduled, ensure that
cb_ops->prepare can be called only once by moving the
cb_ops->prepare paragraph down to just before the rpc_call_async()
call.

Fixes: 2bbfed98a4 ("nfsd: Fix races between nfsd4_cb_release() and nfsd4_shutdown_callback()")
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:12 -05:00
Chuck Lever
fe0e9580e2 NFSD: Convert the callback workqueue to use delayed_work
Normally, NFSv4 callback operations are supposed to be sent to the
client as soon as they are queued up.

In a moment, I will introduce a recovery path where the server has
to wait for the client to reconnect. We don't want a hard busy wait
here -- the callback should be requeued to try again in several
milliseconds.

For now, convert nfsd4_callback from struct work_struct to struct
delayed_work, and queue with a zero delay argument. This should
avoid behavior changes for current operation.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:12 -05:00
Chuck Lever
961b4b5e86 NFSD: Reset cb_seq_status after NFS4ERR_DELAY
I noticed that once an NFSv4.1 callback operation gets a
NFS4ERR_DELAY status on CB_SEQUENCE and then the connection is lost,
the callback client loops, resending it indefinitely.

The switch arm in nfsd4_cb_sequence_done() that handles
NFS4ERR_DELAY uses rpc_restart_call() to rearm the RPC state machine
for the retransmit, but that path does not call the rpc_prepare_call
callback again. Thus cb_seq_status is set to -10008 by the first
NFS4ERR_DELAY result, but is never set back to 1 for the retransmits.

nfsd4_cb_sequence_done() thinks it's getting nothing but a
long series of CB_SEQUENCE NFS4ERR_DELAY replies.

Fixes: 7ba6cad6c8 ("nfsd: New helper nfsd4_cb_sequence_done() for processing more cb errors")
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:12 -05:00
Josef Bacik
16fb9808ab nfsd: make svc_stat per-network namespace instead of global
The final bit of stats that is global is the rpc svc_stat.  Move this
into the nfsd_net struct and use that everywhere instead of the global
struct.  Remove the unused global struct.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:11 -05:00
Josef Bacik
e41ee44cc6 nfsd: remove nfsd_stats, make th_cnt a global counter
This is the last global stat, take it out of the nfsd_stats struct and
make it a global part of nfsd, report it the same as always.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:11 -05:00
Josef Bacik
4b14885411 nfsd: make all of the nfsd stats per-network namespace
We have a global set of counters that we modify for all of the nfsd
operations, but now that we're exposing these stats across all network
namespaces we need to make the stats also be per-network namespace.  We
already have some caching stats that are per-network namespace, so move
these definitions into the same counter and then adjust all the helpers
and users of these stats to provide the appropriate nfsd_net struct so
that the stats are maintained for the per-network namespace objects.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:10 -05:00
Josef Bacik
93483ac5fe nfsd: expose /proc/net/sunrpc/nfsd in net namespaces
We are running nfsd servers inside of containers with their own network
namespace, and we want to monitor these services using the stats found
in /proc.  However these are not exposed in the proc inside of the
container, so we have to bind mount the host /proc into our containers
to get at this information.

Separate out the stat counters init and the proc registration, and move
the proc registration into the pernet operations entry and exit points
so that these stats can be exposed inside of network namespaces.

This is an intermediate step, this just exposes the global counters in
the network namespace.  Subsequent patches will move these counters into
the per-network namespace container.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:10 -05:00
Josef Bacik
d98416cc21 nfsd: rename NFSD_NET_* to NFSD_STATS_*
We're going to merge the stats all into per network namespace in
subsequent patches, rename these nn counters to be consistent with the
rest of the stats.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:10 -05:00
Josef Bacik
418b9687de sunrpc: use the struct net as the svc proc private
nfsd is the only thing using this helper, and it doesn't use the private
currently.  When we switch to per-network namespace stats we will need
the struct net * in order to get to the nfsd_net.  Use the net as the
proc private so we can utilize this when we make the switch over.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:09 -05:00
Josef Bacik
3f6ef182f1 sunrpc: remove ->pg_stats from svc_program
Now that this isn't used anywhere, remove it.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:09 -05:00
Josef Bacik
f094323867 sunrpc: pass in the sv_stats struct through svc_create_pooled
Since only one service actually reports the rpc stats there's not much
of a reason to have a pointer to it in the svc_program struct.  Adjust
the svc_create_pooled function to take the sv_stats as an argument and
pass the struct through there as desired instead of getting it from the
svc_program->pg_stats.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:08 -05:00
Josef Bacik
a2214ed588 nfsd: stop setting ->pg_stats for unused stats
A lot of places are setting a blank svc_stats in ->pg_stats and never
utilizing these stats.  Remove all of these extra structs as we're not
reporting these stats anywhere.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:08 -05:00
Josef Bacik
ab42f4d9a2 sunrpc: don't change ->sv_stats if it doesn't exist
We check for the existence of ->sv_stats elsewhere except in the core
processing code.  It appears that only nfsd actual exports these values
anywhere, everybody else just has a write only copy of sv_stats in their
svc_program.  Add a check for ->sv_stats before every adjustment to
allow us to eliminate the stats struct from all the users who don't
report the stats.

Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:07 -05:00
Jorge Mora
31e4bb8fb8 NFSD: fix LISTXATTRS returning more bytes than maxcount
The maxcount is the maximum number of bytes for the LISTXATTRS4resok
result. This includes the cookie and the count for the name array,
thus subtract 12 bytes from the maxcount: 8 (cookie) + 4 (array count)
when filling up the name array.

Fixes: 23e50fe3a5 ("nfsd: implement the xattr functions and en/decode logic")
Signed-off-by: Jorge Mora <mora@netapp.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-01 09:12:07 -05:00