If we sleep after dropping the inode->i_lock, then we are no longer
atomic with respect to the rpc_wake_up() call in pnfs_layout_remove_lseg().
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Ensure that we do return errors from nfs4_proc_layoutget() and that we
don't mark the layout as having failed if the error was due to a
signal or resource problem on the client side.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
We want to be able to pass on the information that the page was not
dirtied under a lock. Instead of adding a flag parameter, do this
by passing a pointer to a 'struct nfs_lock_owner' that may be NULL.
Also reuse this structure in struct nfs_lock_context to carry the
fl_owner_t and pid_t.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
In case of error, the function rpcauth_create() returns ERR_PTR()
and never returns NULL pointer. The NULL test in the return value
check should be replaced with IS_ERR().
dpatch engine is used to auto generated this patch.
(https://github.com/weiyj/dpatch)
Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Pass the checks made by decode_getacl back to __nfs4_get_acl_uncached
so that it knows if the acl has been truncated.
The current overflow checking is broken, resulting in Oopses on
user-triggered nfs4_getfacl calls, and is opaque to the point
where several attempts at fixing it have failed.
This patch tries to clean up the code in addition to fixing the
Oopses by ensuring that the overflow checks are performed in
a single place (decode_getacl). If the overflow check failed,
we will still be able to report the acl length, but at least
we will no longer attempt to cache the acl or copy the
truncated contents to user space.
Reported-by: Sachin Prabhu <sprabhu@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Tested-by: Sachin Prabhu <sprabhu@redhat.com>
Ensure that the user supplied buffer size doesn't cause us to overflow
the 'pages' array.
Also fix up some confusion between the use of PAGE_SIZE and
PAGE_CACHE_SIZE when calculating buffer sizes. We're not using
the page cache for anything here.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
When the NFS_COOKIEVERF helper macro was converted into a static
inline function in commit 99fadcd764 (nfs: convert NFS_*(inode)
helpers to static inline), we broke the initialisation of the
readdir cookies, since that depended on doing a memset with an
argument of 'sizeof(NFS_COOKIEVERF(inode))' which therefore
changed from sizeof(be32 cookieverf[2]) to sizeof(be32 *).
At this point, NFS_COOKIEVERF seems to be more of an obfuscation
than a helper, so the best thing would be to just get rid of it.
Also see: https://bugzilla.kernel.org/show_bug.cgi?id=46881
Reported-by: Andi Kleen <andi@firstfloor.org>
Reported-by: David Binderman <dcb314@hotmail.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org
Currently, we do not take into account the size of the 16 byte
struct nfs4_cached_acl header, when deciding whether or not we should
cache the acl data. Consequently, we will end up allocating an
8k buffer in order to fit a maximum size 4k acl.
This patch adjusts the calculation so that we limit the cache size
to 4k for the acl header+data.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Resetting the cursor xdr->p to a previous value is not a safe
practice: if the xdr_stream has crossed out of the initial iovec,
then a bunch of other fields would need to be reset too.
Fix this issue by using xdr_enter_page() so that the buffer gets
page aligned at the bitmap _before_ we decode it.
Also fix the confusion of the ACL length with the page buffer length
by not adding the base offset to the ACL length...
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org
Ever since commit 0a57cdac3f (NFSv4.1 send layoutreturn to fence
disconnected data server) we've been sending layoutreturn calls
while there is potentially still outstanding I/O to the data
servers. The reason we do this is to avoid races between replayed
writes to the MDS and the original writes to the DS.
When this happens, the BUG_ON() in nfs4_layoutreturn_done can
be triggered because it assumes that we would never call
layoutreturn without knowing that all I/O to the DS is
finished. The fix is to remove the BUG_ON() now that the
assumptions behind the test are obsolete.
Reported-by: Boaz Harrosh <bharrosh@panasas.com>
Reported-by: Tigran Mkrtchyan <tigran.mkrtchyan@desy.de>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org [>=3.5]
since the only user of nfs4_proc_layoutget is send_layoutget, which
ignores its return value, there is no reason to return any value.
Signed-off-by: Idan Kedar <idank@tonian.com>
Signed-off-by: Benny Halevy <bhalevy@tonian.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
we have encountered a bug whereby reading a lot of files (copying
fedora's /bin) from a pNFS mount and hitting Ctrl+C in the middle caused
a general protection fault in xdr_shrink_bufhead. this function is
called when decoding the response from LAYOUTGET. the decoding is done
by a worker thread, and the caller of LAYOUTGET waits for the worker
thread to complete.
hitting Ctrl+C caused the synchronous wait to end and the next thing the
caller does is to free the pages, so when the worker thread calls
xdr_shrink_bufhead, the pages are gone. therefore, the cleanup of these
pages has been moved to nfs4_layoutget_release.
Signed-off-by: Idan Kedar <idank@tonian.com>
Signed-off-by: Benny Halevy <bhalevy@tonian.com>
Cc: stable@vger.kernel.org
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
v2 and v4 don't use it, so I create two new nfs_rpc_ops functions to
initialize the ACL client only when we are using v3.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
I'm already looking up the nfs subversion in nfs_fs_mount(), so I have
easy access to rpc_ops that used to be difficult to reach. This allows
me to set up a different mount path for NFS v2/3 and NFS v4.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
fl_type is not a bitmap.
Reported-by: Al Viro <viro@ZenIV.linux.org.uk>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The NFS v4 file inode operations are already already in nfs4proc.c, so
this patch just needs to move the directory operations to the same file.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
For NFSv4 minor version 0, currently the cl_id_uniquifier allows the
Linux client to generate a unique nfs_client_id4 string whenever a
server replies with NFS4ERR_CLID_INUSE.
This implementation seems to be based on a flawed reading of RFC
3530. NFS4ERR_CLID_INUSE actually means that the client has presented
this nfs_client_id4 string with a different principal at some time in
the past, and that lease is still in use on the server.
For a Linux client this might be rather difficult to achieve: the
authentication flavor is named right in the nfs_client_id4.id
string. If we change flavors, we change strings automatically.
So, practically speaking, NFS4ERR_CLID_INUSE means there is some other
client using our string. There is not much that can be done to
recover automatically. Let's make it a permanent error.
Remove the recovery logic in nfs4_proc_setclientid(), and remove the
cl_id_uniquifier field from the nfs_client data structure. And,
remove the authentication flavor from the nfs_client_id4 string.
Keeping the authentication flavor in the nfs_client_id4.id string
means that we could have a separate lease for each authentication
flavor used by mounts on the client. But we want just one lease for
all the mounts on this client.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
NFSv4 state recovery is not always successful. Failure is signalled
by setting the nfs_client.cl_cons_state to a negative (errno) value,
then waking waiters.
Currently this can happen only during mount processing. I'm about to
add an explicit case where state recovery failure during normal
operation should force all NFS requests waiting on that state recovery
to exit.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The gss_mech_list_pseudoflavors() function provides a list of
currently registered GSS pseudoflavors. This list does not include
any non-GSS flavors that have been registered with the RPC client.
nfs4_find_root_sec() currently adds these extra flavors by hand.
Instead, nfs4_find_root_sec() should be looking at the set of flavors
that have been explicitly registered via rpcauth_register(). And,
other areas of code will soon need the same kind of list that
contains all flavors the kernel currently knows about (see below).
Rather than cloning the open-coded logic in nfs4_find_root_sec() to
those new places, introduce a generic RPC function that generates a
full list of registered auth flavors and pseudoflavors.
A new rpc_authops method is added that lists a flavor's
pseudoflavors, if it has any. I encountered an interesting module
loader loop when I tried to get the RPC client to invoke
gss_mech_list_pseudoflavors() by name.
This patch is a pre-requisite for server trunking discovery, and a
pre-requisite for fixing up the in-kernel mount client to do better
automatic security flavor selection.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Squelch compiler warnings:
fs/nfs/nfs4proc.c: In function ‘__nfs4_get_acl_uncached’:
fs/nfs/nfs4proc.c:3811:14: warning: comparison between signed and
unsigned integer expressions [-Wsign-compare]
fs/nfs/nfs4proc.c:3818:15: warning: comparison between signed and
unsigned integer expressions [-Wsign-compare]
Introduced by commit bf118a34 "NFSv4: include bitmap in nfsv4 get
acl data", Dec 7, 2011.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
As a finishing touch, add appropriate documenting comments and some
debugging printk's.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Clean up: Instead of open-coded flag manipulation, use test_bit() and
clear_bit() just like all other accessors of the state->flag field.
This also eliminates several unnecessary implicit integer type
conversions.
To make it absolutely clear what is going on, a number of comments
are introduced.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The "state->flags & flags" test in nfs41_check_expired_stateid()
allows the state manager to squelch a TEST_STATEID operation when
it is known for sure that a state ID is no longer valid. If the
lease was purged, for example, the client already knows that state
ID is now defunct.
But open recovery is still needed for that inode.
To force a call to nfs4_open_expired(), change the default return
value for nfs41_check_expired_stateid() to force open recovery, and
the default return value for nfs41_check_locks() to force lock
recovery, if the requested flags are clear. Fix suggested by Bryan
Schumaker.
Also, the presence of a delegation state ID must not prevent normal
open recovery. The delegation state ID must be cleared if it was
revoked, but once cleared I don't think it's presence or absence has
any bearing on whether open recovery is still needed. So the logic
is adjusted to ignore the TEST_STATEID result for the delegation
state ID.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The result of a TEST_STATEID operation can indicate a few different
things:
o If NFS_OK is returned, then the client can continue using the
state ID under test, and skip recovery.
o RFC 5661 says that if the state ID was revoked, then the client
must perform an explicit FREE_STATEID before trying to re-open.
o If the server doesn't recognize the state ID at all, then no
FREE_STATEID is needed, and the client can immediately continue
with open recovery.
Let's err on the side of caution: if the server clearly tells us the
state ID is unknown, we skip the FREE_STATEID. For any other error,
we issue a FREE_STATEID. Sometimes that FREE_STATEID will be
unnecessary, but leaving unused state IDs on the server needlessly
ties up resources.
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The TEST_STATEID and FREE_STATEID operations can return
-NFS4ERR_BAD_STATEID, -NFS4ERR_OLD_STATEID, or -NFS4ERR_DEADSESSION.
nfs41_{test,free}_stateid() should not pass these errors to
nfs4_handle_exception() during state recovery, since that will
recursively kick off state recovery again, resulting in a deadlock.
In particular, when the TEST_STATEID operation returns NFS4_OK,
res.status can contain one of these errors. _nfs41_test_stateid()
replaces NFS4_OK with the value in res.status, which is then returned
to callers.
But res.status is not passed through nfs4_stat_to_errno(), and thus is
a positive NFS4ERR value. Currently callers are only interested in
!NFS4_OK, and nfs4_handle_exception() ignores positive values.
Thus the res.status values are currently ignored by
nfs4_handle_exception() and won't cause the deadlock above. Thanks to
this missing negative, it is only when these operations fail (which
is very rare) that a deadlock can occur.
Bryan agrees the original intent was to return res.status as a
negative NFS4ERR value to callers of nfs41_test_stateid().
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
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: Miklos Szeredi <mszeredi@suse.cz>
CC: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
pNFS needs to select a write function based on the layout driver
currently in use, so I let each NFS version decide how to best handle
initializing writes.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
pNFS needs to select a read function based on the layout driver
currently in use, so I let each NFS version decide how to best handle
initializing reads.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
This gives NFS v4 a way to set up callbacks and sessions without v2 or
v3 having to do them as well.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
NFS v4 needs a way to shut down callbacks and sessions, but v2 and v3
don't.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Delegations are a v4 feature, so push return_delegation out of the
generic client by creating a new rpc_op and renaming the old function to
be in the nfs v4 "namespace"
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Delegations are a v4 feature, so push them out of the generic code.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The generic client doesn't need to know about pnfs layout drivers, so
this should be done in the v4 code.
Signed-off-by: Bryan Schumaker <bjschuma@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Commit 536e43d12b ATTR_OPEN check can result in
an ia_valid with only ATTR_FILE set, and no NFS_VALID_ATTRS attributes to
request from the server.
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
While nfs4_do_open() expects the fmode argument to be restricted to
combinations of FMODE_READ and FMODE_WRITE, both nfs4_atomic_open()
and nfs4_proc_create will pass the nfs_open_context->mode,
which contains the full fmode_t.
This patch ensures that nfs4_do_open strips the other fmode_t bits,
fixing a problem in which the nfs4_do_open call would result in an
unnecessary delegation return.
Reported-by: Fred Isaman <iisaman@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org
Sservers that only have NFSv4.1 support the
NFS4ERR_MINOR_VERS_MISMATCH error is return on
v4.0 mounts. Mapping that error to EPROTONOSUPPORT
will cause the mount to back off to v3 instead of
failing.
Signed-off-by: Steve Dickson <steved@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
There is no need to bug the user about the server returning an error
on destroy_session. The error will be handled by the state manager,
without any need for further input from anyone else.
So convert that printk into a debugging dprintk.
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
The open recovery code does not need to request a new value for the
mdsthreshold, and so does not allocate a struct nfs4_threshold.
The problem is that encode_getfattr_open() will still request an
mdsthreshold, and so we end up Oopsing in decode_attr_mdsthreshold.
This patch fixes encode_getfattr_open so that it doesn't request an
mdsthreshold when the caller isn't asking for one. It also fixes
decode_attr_mdsthreshold so that it errors if the server returns
an mdsthreshold that we didn't ask for (instead of Oopsing).
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: Andy Adamson <andros@netapp.com>
New features include:
- Rewrite the O_DIRECT code so that it can share the same coalescing and
pNFS functionality as the page cache code.
- Allow the server to provide hints as to when we should use pNFS, and
when it is more efficient to read and write through the metadata
server.
- NFS cache consistency updates:
- Use the ctime to emulate a change attribute for NFSv2/v3 so that
all NFS versions can share the same cache management code.
- New cache management code will only look at the change attribute
and size attribute when deciding whether or not our cached data
is still valid or not.
- Don't request NFSv4 post-op attributes on writes in cases such as
O_DIRECT, where we don't care about data cache consistency, or
when we have a write delegation, and know that our cache is
still consistent.
- Don't request NFSv4 post-op attributes on operations such as
COMMIT, where there are no expected metadata updates.
- Don't request NFSv4 directory post-op attributes in cases where
the operations themselves already return change attribute updates:
i.e. operations such as OPEN, CREATE, REMOVE, LINK and RENAME.
- Speed up 'ls' and friends by using READDIR rather than READDIRPLUS
if we detect no attempts to lookup filenames.
- Improve the code sharing between NFSv2/v3 and v4 mounts
- NFSv4.1 state management efficiency improvements
- More patches in preparation for NFSv4/v4.1 migration functionality.
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Merge tag 'nfs-for-3.5-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
Pull NFS client updates from Trond Myklebust:
"New features include:
- Rewrite the O_DIRECT code so that it can share the same coalescing
and pNFS functionality as the page cache code.
- Allow the server to provide hints as to when we should use pNFS,
and when it is more efficient to read and write through the
metadata server.
- NFS cache consistency updates:
* Use the ctime to emulate a change attribute for NFSv2/v3 so that
all NFS versions can share the same cache management code.
* New cache management code will only look at the change attribute
and size attribute when deciding whether or not our cached data
is still valid or not.
* Don't request NFSv4 post-op attributes on writes in cases such as
O_DIRECT, where we don't care about data cache consistency, or
when we have a write delegation, and know that our cache is still
consistent.
* Don't request NFSv4 post-op attributes on operations such as
COMMIT, where there are no expected metadata updates.
* Don't request NFSv4 directory post-op attributes in cases where
the operations themselves already return change attribute
updates: i.e. operations such as OPEN, CREATE, REMOVE, LINK and
RENAME.
- Speed up 'ls' and friends by using READDIR rather than READDIRPLUS
if we detect no attempts to lookup filenames.
- Improve the code sharing between NFSv2/v3 and v4 mounts
- NFSv4.1 state management efficiency improvements
- More patches in preparation for NFSv4/v4.1 migration functionality."
Fix trivial conflict in fs/nfs/nfs4proc.c that was due to the dcache
qstr name initialization changes (that made the length/hash a 64-bit
union)
* tag 'nfs-for-3.5-1' of git://git.linux-nfs.org/projects/trondmy/linux-nfs: (146 commits)
NFSv4: Add debugging printks to state manager
NFSv4: Map NFS4ERR_SHARE_DENIED into an EACCES error instead of EIO
NFSv4: update_changeattr does not need to set NFS_INO_REVAL_PAGECACHE
NFSv4.1: nfs4_reset_session should use nfs4_handle_reclaim_lease_error
NFSv4.1: Handle other occurrences of NFS4ERR_CONN_NOT_BOUND_TO_SESSION
NFSv4.1: Handle NFS4ERR_CONN_NOT_BOUND_TO_SESSION in the state manager
NFSv4.1: Handle errors in nfs4_bind_conn_to_session
NFSv4.1: nfs4_bind_conn_to_session should drain the session
NFSv4.1: Don't clobber the seqid if exchange_id returns a confirmed clientid
NFSv4.1: Add DESTROY_CLIENTID
NFSv4.1: Ensure we use the correct credentials for bind_conn_to_session
NFSv4.1: Ensure we use the correct credentials for session create/destroy
NFSv4.1: Move NFSPROC4_CLNT_BIND_CONN_TO_SESSION to the end of the operations
NFSv4.1: Handle NFS4ERR_SEQ_MISORDERED when confirming the lease
NFSv4: When purging the lease, we must clear NFS4CLNT_LEASE_CONFIRM
NFSv4: Clean up the error handling for nfs4_reclaim_lease
NFSv4.1: Exchange ID must use GFP_NOFS allocation mode
nfs41: Use BIND_CONN_TO_SESSION for CB_PATH_DOWN*
nfs4.1: add BIND_CONN_TO_SESSION operation
NFSv4.1 test the mdsthreshold hint parameters
...
If a file OPEN is denied due to a share lock, the resulting
NFS4ERR_SHARE_DENIED is currently mapped to the default EIO.
This patch adds a more appropriate mapping, and brings Linux
into line with what Solaris 10 does.
See https://bugzilla.kernel.org/show_bug.cgi?id=43286
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org
