Commit graph

115 commits

Author SHA1 Message Date
Jeff Layton
583772eec7 nfsd: allow for up to 32 callback session slots
nfsd currently only uses a single slot in the callback channel, which is
proving to be a bottleneck in some cases. Widen the callback channel to
a max of 32 slots (subject to the client's target_maxreqs value).

Change the cb_holds_slot boolean to an integer that tracks the current
slot number (with -1 meaning "unassigned").  Move the callback slot
tracking info into the session. Add a new u32 that acts as a bitmap to
track which slots are in use, and a u32 to track the latest callback
target_slotid that the client reports. To protect the new fields, add
a new per-session spinlock (the se_lock). Fix nfsd41_cb_get_slot to always
search for the lowest slotid (using ffs()).

Finally, convert the session->se_cb_seq_nr field into an array of
ints and add the necessary handling to ensure that the seqids get
reset when the slot table grows after shrinking.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-11-18 20:23:13 -05:00
Chuck Lever
a4452e661b NFSD: Add a tracepoint to record canceled async COPY operations
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-11-18 20:23:09 -05:00
NeilBrown
4cc9b9f2bf nfsd: refine and rename NFSD_MAY_LOCK
NFSD_MAY_LOCK means a few different things.
- it means that GSS is not required.
- it means that with NFSEXP_NOAUTHNLM, authentication is not required
- it means that OWNER_OVERRIDE is allowed.

None of these are specific to locking, they are specific to the NLM
protocol.
So:
 - rename to NFSD_MAY_NLM
 - set NFSD_MAY_OWNER_OVERRIDE and NFSD_MAY_BYPASS_GSS in nlm_fopen()
   so that NFSD_MAY_NLM doesn't need to imply these.
 - move the test on NFSEXP_NOAUTHNLM out of nfsd_permission() and
   into fh_verify where other special-case tests on the MAY flags
   happen.  nfsd_permission() can be called from other places than
   fh_verify(), but none of these will have NFSD_MAY_NLM.

Signed-off-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-11-18 20:23:00 -05:00
Jeff Layton
b9376c7e42 nfsd: new tracepoint for after op_func in compound processing
Turn nfsd_compound_encode_err tracepoint into a class and add a new
nfsd_compound_op_err tracepoint.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-11-18 20:22:58 -05:00
Mike Snitzer
76f5af9952 nfsd/localio: fix nfsd_file tracepoints to handle NULL rqstp
Otherwise nfsd_file_acquire, nfsd_file_insert_err, and
nfsd_file_cons_err will hit a NULL pointer when they are enabled and
LOCALIO used.

Example trace output (note xid is 0x0 and LOCALIO flag set):
 nfsd_file_acquire: xid=0x0 inode=0000000069a1b2e7
 may_flags=WRITE|LOCALIO ref=1 nf_flags=HASHED|GC nf_may=WRITE
 nf_file=0000000070123234 status=0

Fixes: c63f0e48fe ("nfsd: add nfsd_file_acquire_local()")
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
2024-10-04 14:52:04 -04:00
Weston Andros Adamson
fa4983862e nfsd: add LOCALIO support
Add server support for bypassing NFS for localhost reads, writes, and
commits. This is only useful when both the client and server are
running on the same host.

If nfsd_open_local_fh() fails then the NFS client will both retry and
fallback to normal network-based read, write and commit operations if
localio is no longer supported.

Care is taken to ensure the same NFS security mechanisms are used
(authentication, etc) regardless of whether localio or regular NFS
access is used.  The auth_domain established as part of the traditional
NFS client access to the NFS server is also used for localio.  Store
auth_domain for localio in nfsd_uuid_t and transfer it to the client
if it is local to the server.

Relative to containers, localio gives the client access to the network
namespace the server has.  This is required to allow the client to
access the server's per-namespace nfsd_net struct.

This commit also introduces the use of NFSD's percpu_ref to interlock
nfsd_destroy_serv and nfsd_open_local_fh, to ensure nn->nfsd_serv is
not destroyed while in use by nfsd_open_local_fh and other LOCALIO
client code.

CONFIG_NFS_LOCALIO enables NFS server support for LOCALIO.

Signed-off-by: Weston Andros Adamson <dros@primarydata.com>
Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Co-developed-by: Mike Snitzer <snitzer@kernel.org>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Co-developed-by: NeilBrown <neilb@suse.de>
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Acked-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
2024-09-23 15:03:30 -04:00
Chuck Lever
71c61a0077 NFSD: Short-circuit fh_verify tracepoints for LOCALIO
LOCALIO will be able to call fh_verify() with a NULL rqstp. In this
case, the existing trace points need to be skipped because they
want to dereference the address fields in the passed-in rqstp.

Temporarily make these trace points conditional to avoid a seg
fault in this case. Putting the "rqstp != NULL" check in the trace
points themselves makes the check more efficient.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Mike Snitzer <snitzer@kernel.org>
Acked-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: NeilBrown <neilb@suse.de>
Signed-off-by: Anna Schumaker <anna.schumaker@oracle.com>
2024-09-23 15:03:30 -04:00
Chuck Lever
0505de9615 NFSD: Wrap async copy operations with trace points
Add an nfsd_copy_async_done to record the timestamp, the final
status code, and the callback stateid of an async copy.

Rename the nfsd_copy_do_async tracepoint to match that naming
convention to make it easier to enable both of these with a
single glob.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-09-20 19:31:03 -04:00
Chuck Lever
d3c430aa97 NFSD: Clean up extra whitespace in trace_nfsd_copy_done
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-09-20 19:31:03 -04:00
Chuck Lever
e1d2697c53 NFSD: Record the callback stateid in copy tracepoints
Match COPY operations up with CB_OFFLOAD operations.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-09-20 19:31:03 -04:00
Chuck Lever
11848e985c NFSD: Display copy stateids with conventional print formatting
Make it easier to grep for s2s COPY stateids in trace logs: Use the
same display format in nfsd_copy_class as is used to display other
stateids.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-09-20 19:31:03 -04:00
Jeff Layton
ba017fd391 nfsd: add more nfsd_cb tracepoints
Add some tracepoints in the callback client RPC operations. Also
add a tracepoint to nfsd4_cb_getattr_done.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-09-20 19:31:03 -04:00
Jeff Layton
c1c9f3ea74 nfsd: track the main opcode for callbacks
Keep track of the "main" opcode for the callback, and display it in the
tracepoint. This makes it simpler to discern what's happening when there
is more than one callback in flight.

The one special case is the CB_NULL RPC. That's not a CB_COMPOUND
opcode, so designate the value 0 for that.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-09-20 19:31:03 -04:00
Steven Rostedt (Google)
2c92ca849f tracing/treewide: Remove second parameter of __assign_str()
With the rework of how the __string() handles dynamic strings where it
saves off the source string in field in the helper structure[1], the
assignment of that value to the trace event field is stored in the helper
value and does not need to be passed in again.

This means that with:

  __string(field, mystring)

Which use to be assigned with __assign_str(field, mystring), no longer
needs the second parameter and it is unused. With this, __assign_str()
will now only get a single parameter.

There's over 700 users of __assign_str() and because coccinelle does not
handle the TRACE_EVENT() macro I ended up using the following sed script:

  git grep -l __assign_str | while read a ; do
      sed -e 's/\(__assign_str([^,]*[^ ,]\) *,[^;]*/\1)/' $a > /tmp/test-file;
      mv /tmp/test-file $a;
  done

I then searched for __assign_str() that did not end with ';' as those
were multi line assignments that the sed script above would fail to catch.

Note, the same updates will need to be done for:

  __assign_str_len()
  __assign_rel_str()
  __assign_rel_str_len()

I tested this with both an allmodconfig and an allyesconfig (build only for both).

[1] https://lore.kernel.org/linux-trace-kernel/20240222211442.634192653@goodmis.org/

Link: https://lore.kernel.org/linux-trace-kernel/20240516133454.681ba6a0@rorschach.local.home

Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Julia Lawall <Julia.Lawall@inria.fr>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Acked-by: Christian König <christian.koenig@amd.com> for the amdgpu parts.
Acked-by: Thomas Hellström <thomas.hellstrom@linux.intel.com> #for
Acked-by: Rafael J. Wysocki <rafael@kernel.org> # for thermal
Acked-by: Takashi Iwai <tiwai@suse.de>
Acked-by: Darrick J. Wong <djwong@kernel.org>	# xfs
Tested-by: Guenter Roeck <linux@roeck-us.net>
2024-05-22 20:14:47 -04:00
Jeff Layton
9320f27fda nfsd: add tracepoint in mark_client_expired_locked
Show client info alongside the number of cl_rpc_users. If that's
elevated, then we can infer that this function returned nfserr_jukebox.

[ cel: For additional debugging of RPC user refcounting ]

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Tested-by: Vladimir Benes <vbenes@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-05-06 09:07:19 -04:00
Chuck Lever
2d49901150 nfsd: new tracepoint for check_slot_seqid
Replace a dprintk in check_slot_seqid with tracepoints. These new
tracepoints track slot sequence numbers during operation.

Suggested-by: Jeffrey Layton <jlayton@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-05-06 09:07:18 -04:00
Jeff Layton
db2acd6e8a nfsd: drop extraneous newline from nfsd tracepoints
We never want a newline in tracepoint output.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Tested-by: Vladimir Benes <vbenes@redhat.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-05-06 09:07:18 -04:00
Steven Rostedt (Google)
c759e60903 tracing: Remove __assign_str_len()
Now that __assign_str() gets the length from the __string() (and
__string_len()) macros, there's no reason to have a separate
__assign_str_len() macro as __assign_str() can get the length of the
string needed.

Also remove __assign_rel_str() although it had no users anyway.

Link: https://lore.kernel.org/linux-trace-kernel/20240223152206.0b650659@gandalf.local.home

Cc: Jeff Layton <jlayton@kernel.org>
Acked-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2024-03-18 10:33:05 -04:00
Steven Rostedt (Google)
9388a2aa45 NFSD: Fix nfsd_clid_class use of __string_len() macro
I'm working on restructuring the __string* macros so that it doesn't need
to recalculate the string twice. That is, it will save it off when
processing __string() and the __assign_str() will not need to do the work
again as it currently does.

Currently __string_len(item, src, len) doesn't actually use "src", but my
changes will require src to be correct as that is where the __assign_str()
will get its value from.

The event class nfsd_clid_class has:

  __string_len(name, name, clp->cl_name.len)

But the second "name" does not exist and causes my changes to fail to
build. That second parameter should be: clp->cl_name.data.

Link: https://lore.kernel.org/linux-trace-kernel/20240222122828.3d8d213c@gandalf.local.home

Cc: Neil Brown <neilb@suse.de>
Cc: Olga Kornievskaia <kolga@netapp.com>
Cc: Dai Ngo <Dai.Ngo@oracle.com>
Cc: Tom Talpey <tom@talpey.com>
Cc: stable@vger.kernel.org
Fixes: d27b74a867 ("NFSD: Use new __string_len C macros for nfsd_clid_class")
Acked-by: Chuck Lever <chuck.lever@oracle.com>
Acked-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2024-03-18 10:17:41 -04:00
Chuck Lever
9b350d3e34 NFSD: Clean up nfsd4_encode_replay()
Replace open-coded encoding logic with the use of conventional XDR
utility functions. Add a tracepoint to make replays observable in
field troubleshooting situations.

The WARN_ON is removed. A stack trace is of little use, as there is
only one call site for nfsd4_encode_replay(), and a buffer length
shortage here is unlikely.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-03-09 13:57:50 -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
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
d0ab8b649b NFSD: Remove nfsd_drc_gc() tracepoint
This trace point was for debugging the DRC's garbage collection. In
the field it's just noise.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2024-01-07 17:54:25 -05:00
Dai Ngo
5896a87054 NFSD: add trace points to track server copy progress
Add trace points on destination server to track inter and intra
server copy operations.

Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Tested-by: Chen Hanxiao <chenhx.fnst@fujitsu.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-10-16 12:44:00 -04:00
Chuck Lever
e7421ce714 NFSD: Rename struct svc_cacherep
The svc_ prefix is identified with the SunRPC layer. Although the
duplicate reply cache caches RPC replies, it is only for the NFS
protocol. Rename the struct to better reflect its purpose.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-08-29 17:45:22 -04:00
Chuck Lever
a9507f6af1 NFSD: Replace nfsd_prune_bucket()
Enable nfsd_prune_bucket() to drop the bucket lock while calling
kfree(). Use the same pattern that Jeff recently introduced in the
NFSD filecache.

A few percpu operations are moved outside the lock since they
temporarily disable local IRQs which is expensive and does not
need to be done while the lock is held.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-08-29 17:45:22 -04:00
Dai Ngo
1d3dd1d56c NFSD: Enable write delegation support
This patch grants write delegations for OPEN with NFS4_SHARE_ACCESS_WRITE
if there is no conflict with other OPENs.

Write delegation conflicts with another OPEN, REMOVE, RENAME and SETATTR
are handled the same as read delegation using notify_change,
try_break_deleg.

The NFSv4.0 protocol does not enable a server to determine that a
conflicting GETATTR originated from the client holding the
delegation versus coming from some other client. With NFSv4.1 and
later, the SEQUENCE operation that begins each COMPOUND contains a
client ID, so delegation recall can be safely squelched in this case.

With NFSv4.0, however, the server must recall or send a CB_GETATTR
(per RFC 7530 Section 16.7.5) even when the GETATTR originates from
the client holding that delegation.

An NFSv4.0 client can trigger a pathological situation if it always
sends a DELEGRETURN preceded by a conflicting GETATTR in the same
COMPOUND. COMPOUND execution will always stop at the GETATTR and the
DELEGRETURN will never get executed. The server eventually revokes
the delegation, which can result in loss of open or lock state.

Tracepoint added to track whether read or write delegation is granted.

Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-08-29 17:45:22 -04:00
Chuck Lever
39d432fc76 NFSD: trace nfsctl operations
Add trace log eye-catchers that record the arguments used to
configure NFSD. This helps when troubleshooting the NFSD
administrative interfaces.

These tracepoints can capture NFSD start-up and shutdown times and
parameters, changes in lease time and thread count, and a request
to end the namespace's NFSv4 grace period, in addition to the set
of NFS versions that are enabled.

Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-06-05 09:01:43 -04:00
Azeem Shaikh
21a3f33289 NFSD: Remove open coding of string copy
Instead of open coding a __dynamic_array(), use the __string() and
__assign_str() helper macros that exist for this kind of use case.

Part of an effort to remove deprecated strlcpy() [1] completely from the
kernel[2].

[1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy
[2] https://github.com/KSPP/linux/issues/89

Fixes: 3c92fba557 ("NFSD: Enhance the nfsd_cb_setup tracepoint")
Signed-off-by: Azeem Shaikh <azeemshaikh38@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-05-15 08:03:04 -04:00
Jeff Layton
4c475eee02 nfsd: don't fsync nfsd_files on last close
Most of the time, NFSv4 clients issue a COMMIT before the final CLOSE of
an open stateid, so with NFSv4, the fsync in the nfsd_file_free path is
usually a no-op and doesn't block.

We have a customer running knfsd over very slow storage (XFS over Ceph
RBD). They were using the "async" export option because performance was
more important than data integrity for this application. That export
option turns NFSv4 COMMIT calls into no-ops. Due to the fsync in this
codepath however, their final CLOSE calls would still stall (since a
CLOSE effectively became a COMMIT).

I think this fsync is not strictly necessary. We only use that result to
reset the write verifier. Instead of fsync'ing all of the data when we
free an nfsd_file, we can just check for writeback errors when one is
acquired and when it is freed.

If the client never comes back, then it'll never see the error anyway
and there is no point in resetting it. If an error occurs after the
nfsd_file is removed from the cache but before the inode is evicted,
then it will reset the write verifier on the next nfsd_file_acquire,
(since there will be an unseen error).

The only exception here is if something else opens and fsyncs the file
during that window. Given that local applications work with this
limitation today, I don't see that as an issue.

Link: https://bugzilla.redhat.com/show_bug.cgi?id=2166658
Fixes: ac3a2585f0 ("nfsd: rework refcounting in filecache")
Reported-and-tested-by: Pierguido Lambri <plambri@redhat.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-02-20 09:20:59 -05:00
Jeff Layton
0b3a551fa5 nfsd: fix handling of cached open files in nfsd4_open codepath
Commit fb70bf124b ("NFSD: Instantiate a struct file when creating a
regular NFSv4 file") added the ability to cache an open fd over a
compound. There are a couple of problems with the way this currently
works:

It's racy, as a newly-created nfsd_file can end up with its PENDING bit
cleared while the nf is hashed, and the nf_file pointer is still zeroed
out. Other tasks can find it in this state and they expect to see a
valid nf_file, and can oops if nf_file is NULL.

Also, there is no guarantee that we'll end up creating a new nfsd_file
if one is already in the hash. If an extant entry is in the hash with a
valid nf_file, nfs4_get_vfs_file will clobber its nf_file pointer with
the value of op_file and the old nf_file will leak.

Fix both issues by making a new nfsd_file_acquirei_opened variant that
takes an optional file pointer. If one is present when this is called,
we'll take a new reference to it instead of trying to open the file. If
the nfsd_file already has a valid nf_file, we'll just ignore the
optional file and pass the nfsd_file back as-is.

Also rework the tracepoints a bit to allow for an "opened" variant and
don't try to avoid counting acquisitions in the case where we already
have a cached open file.

Fixes: fb70bf124b ("NFSD: Instantiate a struct file when creating a regular NFSv4 file")
Cc: Trond Myklebust <trondmy@hammerspace.com>
Reported-by: Stanislav Saner <ssaner@redhat.com>
Reported-and-Tested-by: Ruben Vestergaard <rubenv@drcmr.dk>
Reported-and-Tested-by: Torkil Svensgaard <torkil@drcmr.dk>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2023-01-06 13:17:06 -05:00
Jeff Layton
ac3a2585f0 nfsd: rework refcounting in filecache
The filecache refcounting is a bit non-standard for something searchable
by RCU, in that we maintain a sentinel reference while it's hashed. This
in turn requires that we have to do things differently in the "put"
depending on whether its hashed, which we believe to have led to races.

There are other problems in here too. nfsd_file_close_inode_sync can end
up freeing an nfsd_file while there are still outstanding references to
it, and there are a number of subtle ToC/ToU races.

Rework the code so that the refcount is what drives the lifecycle. When
the refcount goes to zero, then unhash and rcu free the object. A task
searching for a nfsd_file is allowed to bump its refcount, but only if
it's not already 0. Ensure that we don't make any other changes to it
until a reference is held.

With this change, the LRU carries a reference. Take special care to deal
with it when removing an entry from the list, and ensure that we only
repurpose the nf_lru list_head when the refcount is 0 to ensure
exclusive access to it.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-12-11 11:03:09 -05:00
Dai Ngo
638593be55 NFSD: add CB_RECALL_ANY tracepoints
Add tracepoints to trace start and end of CB_RECALL_ANY operation.

Signed-off-by: Dai Ngo <dai.ngo@oracle.com>
[ cel: added show_rca_mask() macro ]
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-12-10 11:01:12 -05:00
Chuck Lever
d7064eaf68 NFSD: Add an nfsd_file_fsync tracepoint
Add a tracepoint to capture the number of filecache-triggered fsync
calls and which files needed it. Also, record when an fsync triggers
a write verifier reset.

Examples:

<...>-97    [007]   262.505611: nfsd_file_free:       inode=0xffff888171e08140 ref=0 flags=GC may=WRITE nf_file=0xffff8881373d2400
<...>-97    [007]   262.505612: nfsd_file_fsync:      inode=0xffff888171e08140 ref=0 flags=GC may=WRITE nf_file=0xffff8881373d2400 ret=0
<...>-97    [007]   262.505623: nfsd_file_free:       inode=0xffff888171e08dc0 ref=0 flags=GC may=WRITE nf_file=0xffff8881373d1e00
<...>-97    [007]   262.505624: nfsd_file_fsync:      inode=0xffff888171e08dc0 ref=0 flags=GC may=WRITE nf_file=0xffff8881373d1e00 ret=0

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
2022-12-10 11:00:04 -05:00
Jeff Layton
8214118589 nfsd: reorganize filecache.c
In a coming patch, we're going to rework how the filecache refcounting
works. Move some code around in the function to reduce the churn in the
later patches, and rename some of the functions with (hopefully) clearer
names: nfsd_file_flush becomes nfsd_file_fsync, and
nfsd_file_unhash_and_dispose is renamed to nfsd_file_unhash_and_queue.

Also, the nfsd_file_put_final tracepoint is renamed to nfsd_file_free,
to better match the name of the function from which it's called.

Signed-off-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: NeilBrown <neilb@suse.de>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
2022-11-28 12:54:48 -05:00
Chuck Lever
a1c74569bb NFSD: Trace delegation revocations
Delegation revocation is an exceptional event that is not otherwise
visible externally (eg, no network traffic is emitted). Generate a
trace record when it occurs so that revocation can be observed or
other activity can be triggered. Example:

nfsd-1104  [005]  1912.002544: nfsd_stid_revoke:        client 633c9343:4e82788d stateid 00000003:00000001 ref=2 type=DELEG

Trace infrastructure is provided for subsequent additional tracing
related to nfs4_stid activity.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
2022-11-28 12:54:46 -05:00
Chuck Lever
20eee313ff NFSD: Trace stateids returned via DELEGRETURN
Handing out a delegation stateid is recorded with the
nfsd_deleg_read tracepoint, but there isn't a matching tracepoint
for recording when the stateid is returned.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
2022-11-28 12:54:46 -05:00
Chuck Lever
4d1ea84557 NFSD: Add an NFSD_FILE_GC flag to enable nfsd_file garbage collection
NFSv4 operations manage the lifetime of nfsd_file items they use by
means of NFSv4 OPEN and CLOSE. Hence there's no need for them to be
garbage collected.

Introduce a mechanism to enable garbage collection for nfsd_file
items used only by NFSv2/3 callers.

Note that the change in nfsd_file_put() ensures that both CLOSE and
DELEGRETURN will actually close out and free an nfsd_file on last
reference of a non-garbage-collected file.

Link: https://bugzilla.linux-nfs.org/show_bug.cgi?id=394
Suggested-by: Trond Myklebust <trond.myklebust@hammerspace.com>
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Tested-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: NeilBrown <neilb@suse.de>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
2022-11-28 12:54:45 -05:00
Chuck Lever
5a01c80544 NFSD: Fix trace_nfsd_fh_verify_err() crasher
Now that the nfsd_fh_verify_err() tracepoint is always called on
error, it needs to handle cases where the filehandle is not yet
fully formed.

Fixes: 93c128e709 ("nfsd: ensure we always call fh_verify_error tracepoint")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
2022-11-14 08:43:35 -05:00
Chuck Lever
c035362eb9 NFSD: Add a mechanism to wait for a DELEGRETURN
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>
2022-09-26 14:02:32 -04:00
Chuck Lever
1035d65446 NFSD: Add tracepoints to report NFSv4 callback completions
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>
2022-09-26 14:02:32 -04:00
Chuck Lever
de29cf7e6c NFSD: Trace NFSv4 COMPOUND tags
The Linux NFSv4 client implementation does not use COMPOUND tags,
but the Solaris and MacOS implementations do, and so does pynfs.
Record these eye-catchers in the server's trace buffer to annotate
client requests while troubleshooting.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
2022-09-26 14:02:31 -04:00
Chuck Lever
948755efc9 NFSD: Replace dprintk() call site in fh_verify()
Record permission errors in the trace log. Note that the new trace
event is conditional, so it will only record non-zero return values
from nfsd_permission().

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
2022-09-26 14:02:31 -04:00
Chuck Lever
b40a283947 NFSD: Move nfsd_file_trace_alloc() tracepoint
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>
2022-07-29 20:16:07 -04:00
Chuck Lever
be0230069f NFSD: Separate tracepoints for acquire and create
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>
2022-07-29 20:15:54 -04:00
Chuck Lever
ce502f81ba NFSD: Convert the filecache to use rhashtable
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>
2022-07-29 20:14:25 -04:00