linux-stable.git/include/linux/sunrpc/svc.h, branch v6.8

Merge tag 'nfs-for-6.8-1' of git://git.linux-nfs.org/projects/anna/linux-nfs

2024-01-11T00:13:57+00:00

Pull nfs client updates from Anna Schumaker:
 "New Features:
   - Always ask for type with READDIR
   - Remove nfs_writepage()

  Bugfixes:
   - Fix a suspicious RCU usage warning
   - Fix a blocklayoutdriver reference leak
   - Fix the block driver's calculation of layoutget size
   - Fix handling NFS4ERR_RETURNCONFLICT
   - Fix _xprt_switch_find_current_entry()
   - Fix v4.1 backchannel request timeouts
   - Don't add zero-length pnfs block devices
   - Use the parent cred in nfs_access_login_time()

  Cleanups:
   - A few improvements when dealing with referring calls from the
     server
   - Clean up various unused variables, struct fields, and function
     calls
   - Various tracepoint improvements"

* tag 'nfs-for-6.8-1' of git://git.linux-nfs.org/projects/anna/linux-nfs: (21 commits)
  NFSv4.1: Use the nfs_client's rpc timeouts for backchannel
  SUNRPC: Fixup v4.1 backchannel request timeouts
  rpc_pipefs: Replace one label in bl_resolve_deviceid()
  nfs: Remove writepage
  NFS: drop unused nfs_direct_req bytes_left
  pNFS: Fix the pnfs block driver's calculation of layoutget size
  nfs: print fileid in lookup tracepoints
  nfs: rename the nfs_async_rename_done tracepoint
  nfs: add new tracepoint at nfs4 revalidate entry point
  SUNRPC: fix _xprt_switch_find_current_entry logic
  NFSv4.1/pnfs: Ensure we handle the error NFS4ERR_RETURNCONFLICT
  NFSv4.1: if referring calls are complete, trust the stateid argument
  NFSv4: Track the number of referring calls in struct cb_process_state
  NFS: Use parent's objective cred in nfs_access_login_time()
  NFSv4: Always ask for type with READDIR
  pnfs/blocklayout: Don't add zero-length pnfs_block_dev
  blocklayoutdriver: Fix reference leak of pnfs_device_node
  SUNRPC: Fix a suspicious RCU usage warning
  SUNRPC: Create a helper function for accessing the rpc_clnt's xprt_switch
  SUNRPC: Remove unused function rpc_clnt_xprt_switch_put()
  ...

SUNRPC: discard sv_refcnt, and svc_get/svc_put

2024-01-07T22:54:33+00:00

sv_refcnt is no longer useful.
lockd and nfs-cb only ever have the svc active when there are a non-zero
number of threads, so sv_refcnt mirrors sv_nrthreads.

nfsd also keeps the svc active between when a socket is added and when
the first thread is started, but we don't really need a refcount for
that.  We can simply not destroy the svc while there are any permanent
sockets attached.

So remove sv_refcnt and the get/put functions.
Instead of a final call to svc_put(), call svc_destroy() instead.
This is changed to also store NULL in the passed-in pointer to make it
easier to avoid use-after-free situations.

Signed-off-by: NeilBrown 
Reviewed-by: Jeff Layton 
Signed-off-by: Chuck Lever

svc: don't hold reference for poolstats, only mutex.

2024-01-07T22:54:33+00:00

A future patch will remove refcounting on svc_serv as it is of little
use.
It is currently used to keep the svc around while the pool_stats file is
open.
Change this to get the pointer, protected by the mutex, only in
seq_start, and the release the mutex in seq_stop.
This means that if the nfsd server is stopped and restarted while the
pool_stats file it open, then some pool stats info could be from the
first instance and some from the second.  This might appear odd, but is
unlikely to be a problem in practice.

Signed-off-by: NeilBrown 
Reviewed-by: Jeff Layton 
Signed-off-by: Chuck Lever

SUNRPC: Remove RQ_SPLICE_OK

2024-01-07T22:54:26+00:00

This flag is no longer used.

Reviewed-by: Jeff Layton 
Signed-off-by: Chuck Lever

NFSv4.1: Use the nfs_client's rpc timeouts for backchannel

2024-01-04T22:01:01+00:00

For backchannel requests that lookup the appropriate nfs_client, use the
state-management rpc_clnt's rpc_timeout parameters for the backchannel's
response.  When the nfs_client cannot be found, fall back to using the
xprt's default timeout parameters.

Signed-off-by: Benjamin Coddington 
Tested-by: Chuck Lever 
Tested-by: Jeff Layton 
Signed-off-by: Anna Schumaker

NFSD: add rpc_status netlink support

2023-10-16T16:44:09+00:00

Introduce rpc_status netlink support for NFSD in order to dump pending
RPC requests debugging information from userspace.

Closes: https://bugzilla.linux-nfs.org/show_bug.cgi?id=366
Tested-by: Jeff Layton 
Signed-off-by: Lorenzo Bianconi 
Signed-off-by: Chuck Lever

SUNRPC: change the back-channel queue to lwq

2023-10-16T16:44:08+00:00

This removes the need to store and update back-links in the list.
It also remove the need for the _bh version of spin_lock().

Signed-off-by: NeilBrown 
Cc: Trond Myklebust 
Cc: Anna Schumaker 
Signed-off-by: Chuck Lever

SUNRPC: discard sp_lock

2023-10-16T16:44:08+00:00

sp_lock is now only used to protect sp_all_threads.  This isn't needed
as sp_all_threads is only manipulated through svc_set_num_threads(),
which is already serialized.  Read-acccess only requires rcu_read_lock().
So no more locking is needed.

Signed-off-by: NeilBrown 
Signed-off-by: Chuck Lever

SUNRPC: change sp_nrthreads to atomic_t

2023-10-16T16:44:07+00:00

Using an atomic_t avoids the need to take a spinlock (which can soon be
removed).

Choosing a thread to kill needs to be careful as we cannot set the "die
now" bit atomically with the test on the count.  Instead we temporarily
increase the count.

Signed-off-by: NeilBrown 
Signed-off-by: Chuck Lever

SUNRPC: use lwq for sp_sockets - renamed to sp_xprts

2023-10-16T16:44:07+00:00

lwq avoids using back pointers in lists, and uses less locking.
This introduces a new spinlock, but the other one will be removed in a
future patch.

For svc_clean_up_xprts(), we now dequeue the entire queue, walk it to
remove and process the xprts that need cleaning up, then re-enqueue the
remaining queue.

Signed-off-by: NeilBrown 
Signed-off-by: Chuck Lever