linux-stable.git/fs/nfs/callback_proc.c, branch linux-4.9.y

NFS: Fix bool initialization/comparison

2020-02-14T21:31:07+00:00

[ Upstream commit 6089dd0d731028531fb1148be9fd33274ff90da4 ]

Bool initializations should use true and false. Bool tests don't need
comparisons.

Signed-off-by: Thomas Meyer 
Signed-off-by: Anna Schumaker 
Signed-off-by: Sasha Levin

NFSv4.1: Fix a potential layoutget/layoutrecall deadlock

2018-09-19T20:47:16+00:00

[ Upstream commit bd3d16a887b0c19a2a20d35ffed499e3a3637feb ]

If the client is sending a layoutget, but the server issues a callback
to recall what it thinks may be an outstanding layout, then we may find
an uninitialised layout attached to the inode due to the layoutget.
In that case, it is appropriate to return NFS4ERR_NOMATCHING_LAYOUT
rather than NFS4ERR_DELAY, as the latter can end up deadlocking.

Signed-off-by: Trond Myklebust 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

NFSv4: Revert commit 5f83d86cf531d ("NFSv4.x: Fix wraparound issues..")

2018-07-03T09:23:16+00:00

commit fc40724fc6731d90cc7fb6d62d66135f85a33dd2 upstream.

The correct behaviour for NFSv4 sequence IDs is to wrap around
to the value 0 after 0xffffffff.
See https://tools.ietf.org/html/rfc5661#section-2.10.6.1

Fixes: 5f83d86cf531d ("NFSv4.x: Fix wraparound issues when validing...")
Cc: stable@vger.kernel.org # 4.6+
Signed-off-by: Trond Myklebust 
Signed-off-by: Greg Kroah-Hartman

nfs: allow blocking locks to be awoken by lock callbacks

2016-09-22T19:54:27+00:00

Add a waitqueue head to the client structure. Have clients set a wait
on that queue prior to requesting a lock from the server. If the lock
is blocked, then we can use that to wait for wakeups.

Note that we do need to do this "manually" since we need to set the
wait on the waitqueue prior to requesting the lock, but requesting a
lock can involve activities that can block.

However, only do that for NFSv4.1 locks, either by compiling out
all of the waitqueue handling when CONFIG_NFS_V4_1 is disabled, or
skipping all of it at runtime if we're dealing with v4.0, or v4.1
servers that don't send lock callbacks.

Note too that even when we expect to get a lock callback, RFC5661
section 20.11.4 is pretty clear that we still need to poll for them,
so we do still sleep on a timeout. We do however always poll at the
longest interval in that case.

Signed-off-by: Jeff Layton 
[Anna: nfs4_retry_setlk() "status" should default to -ERESTARTSYS]
Signed-off-by: Anna Schumaker

nfs: add handling for CB_NOTIFY_LOCK in client

2016-09-22T17:56:04+00:00

For now, the callback doesn't do anything. Support for that will be
added in later patches.

Signed-off-by: Jeff Layton 
Signed-off-by: Anna Schumaker

NFSv4.1: Remove obsolete and incorrrect assignment in nfs4_callback_sequence

2016-08-28T18:23:27+00:00

Signed-off-by: Trond Myklebust

NFSv4.1: Delay callback processing when there are referring triples

2016-08-28T18:23:26+00:00

If CB_SEQUENCE tells us that the processing of this request depends on
the completion of one or more referring triples (see RFC 5661 Section
2.10.6.3), delay the callback processing until after the RPC requests
being referred to have completed.
If we end up delaying for more than 1/2 second, then fall back to
returning NFS4ERR_DELAY in reply to the callback.

Signed-off-by: Trond Myklebust

NFSv4.1: Fix Oopsable condition in server callback races

2016-08-28T18:23:22+00:00

The slot table hasn't been an array since v3.7. Ensure that we
use nfs4_lookup_slot() to access the slot correctly.

Fixes: 87dda67e7386 ("NFSv4.1: Allow SEQUENCE to resize the slot table...")
Signed-off-by: Trond Myklebust 
Cc: stable@vger.kernel.org # v3.8+

pNFS: Remove redundant pnfs_mark_layout_returned_if_empty()

2016-07-24T20:16:41+00:00

That's already being taken care of in pnfs_layout_remove_lseg().

Signed-off-by: Trond Myklebust

pNFS: Fix CB_LAYOUTRECALL stateid verification

2016-07-24T20:16:38+00:00

We want to evaluate in this order:

If the client holds no layout for this inode, then return
NFS4ERR_NOMATCHING_LAYOUT; it probably forgot the layout.

If the client finds the inode among the list of layouts, but the corresponding
stateid has not yet been initialised, then return NFS4ERR_DELAY to ask the
server to retry once the outstanding LAYOUTGET is complete.

If the current layout stateid's "other" field does not match the recalled
stateid, return NFS4ERR_BAD_STATEID.

If already processing a layout recall with a newer stateid, return
NFS4ERR_OLD_STATEID. This can only happens for servers that are
non-compliant with the NFSv4.1 protocol.

If already processing a layout recall with an older stateid, return
NFS4ERR_DELAY to ask the server to retry once the outstanding
LAYOUTRETURN is complete. Again, this is technically incompliant with
the NFSv4.1 protocol.

If the current layout sequence id is newer than the recalled stateid's
sequence id, return NFS4ERR_OLD_STATEID. This too implies protocol
non-compliance.

If the current layout sequence id is older than the recalled stateid's
sequence id+1, return NFS4ERR_DELAY.

Signed-off-by: Trond Myklebust