linux-toradex.git/fs/lockd, branch v6.6-rc5

SUNRPC: Add enum svc_auth_status

2023-08-29T21:45:22+00:00

In addition to the benefits of using an enum rather than a set of
macros, we now have a named type that can improve static type
checking of function return values.

As part of this change, I removed a stale comment from svcauth.h;
the return values from current implementations of the
auth_ops::release method are all zero/negative errno, not the SVC_OK
enum values as the old comment suggested.

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

SUNRPC: remove timeout arg from svc_recv()

2023-08-29T21:45:22+00:00

Most svc threads have no interest in a timeout.
nfsd sets it to 1 hour, but this is a wart of no significance.

lockd uses the timeout so that it can call nlmsvc_retry_blocked().
It also sometimes calls svc_wake_up() to ensure this is called.

So change lockd to be consistent and always use svc_wake_up() to trigger
nlmsvc_retry_blocked() - using a timer instead of a timeout to
svc_recv().

And change svc_recv() to not take a timeout arg.

This makes the sp_threads_timedout counter always zero.

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

SUNRPC: change svc_recv() to return void.

2023-08-29T21:45:22+00:00

svc_recv() currently returns a 0 on success or one of two errors:
 - -EAGAIN means no message was successfully received
 - -EINTR means the thread has been told to stop

Previously nfsd would stop as the result of a signal as well as
following kthread_stop().  In that case the difference was useful: EINTR
means stop unconditionally.  EAGAIN means stop if kthread_should_stop(),
continue otherwise.

Now threads only exit when kthread_should_stop() so we don't need the
distinction.

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

SUNRPC: call svc_process() from svc_recv().

2023-08-29T21:45:22+00:00

All callers of svc_recv() go on to call svc_process() on success.
Simplify callers by having svc_recv() do that for them.

This loses one call to validate_process_creds() in nfsd.  That was
debugging code added 14 years ago.  I don't think we need to keep it.

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

lockd: remove SIGKILL handling

2023-08-29T21:45:22+00:00

lockd allows SIGKILL and responds by dropping all locks and restarting
the grace period.  This functionality has been present since 2.1.32 when
lockd was added to Linux.

This functionality is undocumented and most likely added as a useful
debug aid.  When there is a need to drop locks, the better approach is
to use /proc/fs/nfsd/unlock_*.

This patch removes SIGKILL handling as part of preparation for removing
all signal handling from sunrpc service threads.

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

fs: lockd: avoid possible wrong NULL parameter

2023-08-29T21:45:22+00:00

clang's static analysis warning: fs/lockd/mon.c: line 293, column 2:
Null pointer passed as 2nd argument to memory copy function.

Assuming 'hostname' is NULL and calling 'nsm_create_handle()', this will
pass NULL as 2nd argument to memory copy function 'memcpy()'. So return
NULL if 'hostname' is invalid.

Fixes: 77a3ef33e2de ("NSM: More clean up of nsm_get_handle()")
Signed-off-by: Su Hui 
Reviewed-by: Nick Desaulniers 
Reviewed-by: Jeff Layton 
Signed-off-by: Chuck Lever

lockd: nlm_blocked list race fixes

2023-08-29T21:45:22+00:00

This patch fixes races when lockd accesses the global nlm_blocked list.
It was mostly safe to access the list because everything was accessed
from the lockd kernel thread context but there exist cases like
nlmsvc_grant_deferred() that could manipulate the nlm_blocked list and
it can be called from any context.

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

Merge tag 'nfs-for-6.5-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs

2023-07-01T21:38:25+00:00

Pull NFS client updates from Trond Myklebust:
"Stable fixes and other bugfixes:

   - nfs: don't report STATX_BTIME in ->getattr

   - Revert 'NFSv4: Retry LOCK on OLD_STATEID during delegation return'
     since it breaks NFSv4 state recovery.

   - NFSv4.1: freeze the session table upon receiving NFS4ERR_BADSESSION

   - Fix the NFSv4.2 xattr cache shrinker_id

   - Force a ctime update after a NFSv4.2 SETXATTR call

  Features and cleanups:

   - NFS and RPC over TLS client code from Chuck Lever

   - Support for use of abstract unix socket addresses with the rpcbind
     daemon

   - Sysfs API to allow shutdown of the kernel RPC client and prevent
     umount() hangs if the server is known to be permanently down

   - XDR cleanups from Anna"

* tag 'nfs-for-6.5-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (33 commits)
  Revert "NFSv4: Retry LOCK on OLD_STATEID during delegation return"
  NFS: Don't cleanup sysfs superblock entry if uninitialized
  nfs: don't report STATX_BTIME in ->getattr
  NFSv4.1: freeze the session table upon receiving NFS4ERR_BADSESSION
  NFSv4.2: fix wrong shrinker_id
  NFSv4: Clean up some shutdown loops
  NFS: Cancel all existing RPC tasks when shutdown
  NFS: add sysfs shutdown knob
  NFS: add a sysfs link to the acl rpc_client
  NFS: add a sysfs link to the lockd rpc_client
  NFS: Add sysfs links to sunrpc clients for nfs_clients
  NFS: add superblock sysfs entries
  NFS: Make all of /sys/fs/nfs network-namespace unique
  NFS: Open-code the nfs_kset kset_create_and_add()
  NFS: rename nfs_client_kobj to nfs_net_kobj
  NFS: rename nfs_client_kset to nfs_kset
  NFS: Add an "xprtsec=" NFS mount option
  NFS: Have struct nfs_client carry a TLS policy field
  SUNRPC: Add a TCP-with-TLS RPC transport class
  SUNRPC: Capture CMSG metadata on client-side receive
  ...

NFS: add a sysfs link to the lockd rpc_client

2023-06-19T19:06:07+00:00

After lockd is started, add a symlink for lockd's rpc_client under
NFS' superblock sysfs.

Signed-off-by: Benjamin Coddington 
Signed-off-by: Trond Myklebust

lockd: drop inappropriate svc_get() from locked_get()

2023-06-12T16:16:34+00:00

The below-mentioned patch was intended to simplify refcounting on the
svc_serv used by locked.  The goal was to only ever have a single
reference from the single thread.  To that end we dropped a call to
lockd_start_svc() (except when creating thread) which would take a
reference, and dropped the svc_put(serv) that would drop that reference.

Unfortunately we didn't also remove the svc_get() from
lockd_create_svc() in the case where the svc_serv already existed.
So after the patch:
 - on the first call the svc_serv was allocated and the one reference
   was given to the thread, so there are no extra references
 - on subsequent calls svc_get() was called so there is now an extra
   reference.
This is clearly not consistent.

The inconsistency is also clear in the current code in lockd_get()
takes *two* references, one on nlmsvc_serv and one by incrementing
nlmsvc_users.   This clearly does not match lockd_put().

So: drop that svc_get() from lockd_get() (which used to be in
lockd_create_svc().

Reported-by: Ido Schimmel 
Closes: https://lore.kernel.org/linux-nfs/ZHsI%2FH16VX9kJQX1@shredder/T/#u
Fixes: b73a2972041b ("lockd: move lockd_start_svc() call into lockd_create_svc()")
Signed-off-by: NeilBrown 
Tested-by: Ido Schimmel 
Signed-off-by: Chuck Lever