Skip to content

K
Kernel

openeuler / Kernel
1 年多 前同步成功

通知 8
Star 0
Fork 0
K
Kernel
切换分支/标签
  1. 05 9月, 2013 1 次提交
    • N
      NFSv4: Don't try to recover NFSv4 locks when they are lost. · ef1820f9
      由 NeilBrown 提交于 
      When an NFSv4 client loses contact with the server it can lose any
locks that it holds.

Currently when it reconnects to the server it simply tries to reclaim
those locks.  This might succeed even though some other client has
held and released a lock in the mean time.  So the first client might
think the file is unchanged, but it isn't.  This isn't good.

If, when recovery happens, the locks cannot be claimed because some
other client still holds the lock, then we get a message in the kernel
logs, but the client can still write.  So two clients can both think
they have a lock and can both write at the same time.  This is equally
not good.

There was a patch a while ago
  http://comments.gmane.org/gmane.linux.nfs/41917

which tried to address some of this, but it didn't seem to go
anywhere.  That patch would also send a signal to the process.  That
might be useful but for now this patch just causes writes to fail.

For NFSv4 (unlike v2/v3) there is a strong link between the lock and
the write request so we can fairly easily fail any IO of the lock is
gone.  While some applications might not expect this, it is still
safer than allowing the write to succeed.

Because this is a fairly big change in behaviour a module parameter,
"recover_locks", is introduced which defaults to true (the current
behaviour) but can be set to "false" to tell the client not to try to
recover things that were lost.
Signed-off-by: NNeilBrown <neilb@suse.de>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
      ef1820f9
  3. 22 8月, 2013 1 次提交
  5. 09 6月, 2013 1 次提交
  7. 12 5月, 2013 1 次提交
    • C
      freezer: add unsafe versions of freezable helpers for NFS · 416ad3c9
      由 Colin Cross 提交于 
      NFS calls the freezable helpers with locks held, which is unsafe
and will cause lockdep warnings when 6aa97070 "lockdep: check
that no locks held at freeze time" is reapplied (it was reverted
in dbf520a9).  NFS shouldn't be doing this, but it has
long-running syscalls that must hold a lock but also shouldn't
block suspend.  Until NFS freeze handling is rewritten to use a
signal to exit out of the critical section, add new *_unsafe
versions of the helpers that will not run the lockdep test when
6aa97070 is reapplied, and call them from NFS.

In practice the likley result of holding the lock while freezing
is that a second task blocked on the lock will never freeze,
aborting suspend, but it is possible to manufacture a case using
the cgroup freezer, the lock, and the suspend freezer to create
a deadlock.  Silencing the lockdep warning here will allow
problems to be found in other drivers that may have a more
serious deadlock risk, and prevent new problems from being added.
Signed-off-by: NColin Cross <ccross@android.com>
Acked-by: NPavel Machek <pavel@ucw.cz>
Acked-by: NTejun Heo <tj@kernel.org>
Signed-off-by: NRafael J. Wysocki <rafael.j.wysocki@intel.com>
      416ad3c9
  9. 23 2月, 2013 1 次提交
  11. 13 12月, 2012 1 次提交
    • A
      SUNRPC handle EKEYEXPIRED in call_refreshresult · eb96d5c9
      由 Andy Adamson 提交于 
      Currently, when an RPCSEC_GSS context has expired or is non-existent
and the users (Kerberos) credentials have also expired or are non-existent,
the client receives the -EKEYEXPIRED error and tries to refresh the context
forever.  If an application is performing I/O, or other work against the share,
the application hangs, and the user is not prompted to refresh/establish their
credentials. This can result in a denial of service for other users.

Users are expected to manage their Kerberos credential lifetimes to mitigate
this issue.

Move the -EKEYEXPIRED handling into the RPC layer. Try tk_cred_retry number
of times to refresh the gss_context, and then return -EACCES to the application.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
      eb96d5c9
  13. 05 9月, 2012 1 次提交
  15. 21 8月, 2012 1 次提交
  17. 31 7月, 2012 2 次提交
  19. 18 7月, 2012 1 次提交
  21. 14 7月, 2012 1 次提交
    • M
      nfs: clean up ->create in nfs_rpc_ops · 8867fe58
      由 Miklos Szeredi 提交于 
      Don't pass nfs_open_context() to ->create().  Only the NFS4 implementation
needed that and only because it wanted to return an open file using open
intents.  That task has been replaced by ->atomic_open so it is not necessary
anymore to pass the context to the create rpc operation.

Despite nfs4_proc_create apparently being okay with a NULL context it Oopses
somewhere down the call chain.  So allocate a context here.
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
CC: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
      8867fe58
  23. 29 6月, 2012 6 次提交
  25. 11 5月, 2012 1 次提交
    • L
      vfs: make it possible to access the dentry hash/len as one 64-bit entry · 26fe5750
      由 Linus Torvalds 提交于 
      This allows comparing hash and len in one operation on 64-bit
architectures.  Right now only __d_lookup_rcu() takes advantage of this,
since that is the case we care most about.

The use of anonymous struct/unions hides the alternate 64-bit approach
from most users, the exception being a few cases where we initialize a
'struct qstr' with a static initializer.  This makes the problematic
cases use a new QSTR_INIT() helper function for that (but initializing
just the name pointer with a "{ .name = xyzzy }" initializer remains
valid, as does just copying another qstr structure).
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      26fe5750
  27. 28 4月, 2012 4 次提交
  29. 21 3月, 2012 4 次提交
  31. 07 12月, 2011 1 次提交
  33. 05 11月, 2011 1 次提交
    • J
      nfs: when attempting to open a directory, fall back on normal lookup (try #5) · 1788ea6e
      由 Jeff Layton 提交于 
      commit d953126a changed how nfs_atomic_lookup handles an -EISDIR return
from an OPEN call. Prior to that patch, that caused the client to fall
back to doing a normal lookup. When that patch went in, the code began
returning that error to userspace. The d_revalidate codepath however
never had the corresponding change, so it was still possible to end up
with a NULL ctx->state pointer after that.

That patch caused a regression. When we attempt to open a directory that
does not have a cached dentry, that open now errors out with EISDIR. If
you attempt the same open with a cached dentry, it will succeed.

Fix this by reverting the change in nfs_atomic_lookup and allowing
attempts to open directories to fall back to a normal lookup

Also, add a NFSv4-specific f_ops->open routine that just returns
-ENOTDIR. This should never be called if things are working properly,
but if it ever is, then the dprintk may help in debugging.

To facilitate this, a new file_operations field is also added to the
nfs_rpc_ops struct.

Cc: stable@kernel.org
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
      1788ea6e
  35. 01 8月, 2011 1 次提交
  37. 25 3月, 2011 1 次提交
  39. 12 3月, 2011 1 次提交
  41. 24 10月, 2010 1 次提交
  43. 22 9月, 2010 1 次提交
  45. 18 9月, 2010 3 次提交
  47. 17 9月, 2010 1 次提交
  49. 15 5月, 2010 2 次提交