Skip to content

L
linux
Switch branch/tag
  1. 22 Apr, 2010 1 commit
    • J. Bruce Fields's avatar
      nfsd4: don't sleep in lease-break callback · b5a1a81e
      J. Bruce Fields authored 
      The NFSv4 server's fl_break callback can sleep (dropping the BKL), in
order to allocate a new rpc task to send a recall to the client.

As far as I can tell this doesn't cause any races in the current code,
but the analysis is difficult.  Also, the sleep here may complicate the
move away from the BKL.

So, just schedule some work to do the job for us instead.  The work will
later also prove useful for restarting a call after the callback
information is changed.
Signed-off-by: default avatarJ. Bruce Fields <bfields@citi.umich.edu>
      b5a1a81e
  3. 19 Apr, 2010 1 commit
  5. 17 Apr, 2010 1 commit
  7. 02 Apr, 2010 4 commits
  9. 30 Mar, 2010 1 commit
  11. 24 Mar, 2010 1 commit
  13. 22 Mar, 2010 1 commit
    • Jeff Layton's avatar
      nfsd: don't break lease while servicing a COMMIT · 91885258
      Jeff Layton authored 
      This is the second attempt to fix the problem whereby a COMMIT call
causes a lease break and triggers a possible deadlock.

The problem is that nfsd attempts to break a lease on a COMMIT call.
This triggers a delegation recall if the lease is held for a delegation.
If the client is the one holding the delegation and it's the same one on
which it's issuing the COMMIT, then it can't return that delegation
until the COMMIT is complete. But, nfsd won't complete the COMMIT until
the delegation is returned. The client and server are essentially
deadlocked until the state is marked bad (due to the client not
responding on the callback channel).

The first patch attempted to deal with this by eliminating the open of
the file altogether and simply had nfsd_commit pass a NULL file pointer
to the vfs_fsync_range. That would conflict with some work in progress
by Christoph Hellwig to clean up the fsync interface, so this patch
takes a different approach.

This declares a new NFSD_MAY_NOT_BREAK_LEASE access flag that indicates
to nfsd_open that it should not break any leases when opening the file,
and has nfsd_commit set that flag on the nfsd_open call.

For now, this patch leaves nfsd_commit opening the file with write
access since I'm not clear on what sort of access would be more
appropriate.
Signed-off-by: default avatarJeff Layton <jlayton@redhat.com>
Cc: stable@kernel.org
Signed-off-by: default avatarJ. Bruce Fields <bfields@citi.umich.edu>
      91885258
  15. 16 Mar, 2010 1 commit
  17. 15 Mar, 2010 1 commit
    • NeilBrown's avatar
      sunrpc: never return expired entries in sunrpc_cache_lookup · d202cce8
      NeilBrown authored 
      If sunrpc_cache_lookup finds an expired entry, remove it from
the cache and return a freshly created non-VALID entry instead.
This ensures that we only ever get a usable entry, or an
entry that will become usable once an update arrives.
i.e. we will never need to repeat the lookup.

This allows us to remove the 'is_expired' test from cache_check
(i.e. from cache_is_valid).  cache_check should never get an expired
entry as 'lookup' will never return one.  If it does happen - due to
inconvenient timing - then just accept it as still valid, it won't be
very much past it's use-by date.
Signed-off-by: default avatarNeilBrown <neilb@suse.de>
Signed-off-by: default avatarJ. Bruce Fields <bfields@citi.umich.edu>
      d202cce8
  19. 14 Mar, 2010 2 commits
  21. 09 Mar, 2010 1 commit
  23. 08 Mar, 2010 25 commits
GitLab Nexedi Edition | About GitLab | About Nexedi | 沪ICP备2021021310号-2 | 沪ICP备2021021310号-7