d_alloc_and_lookup() calls i_op->lookup method due to
rootfh changes his fsid.

During mount i_op of NFS root inode is set to
nfs_mountpoint_inode_operations, if rpc_ops->getroot()
and rpc_ops->getattr() return different fsid.

After that  nfs_follow_remote_path() raised oops:

   BUG: unable to handle kernel NULL pointer dereference at (null)
   IP: [<          (null)>]           (null)

stack trace:

     d_alloc_and_lookup+0x4c/0x74
     do_lookup+0x1e3/0x280
     link_path_walk+0x12e/0xab0
     nfs4_remote_get_sb+0x56/0x2c0 [nfs]
     path_walk+0x67/0xe0
     vfs_path_lookup+0x8e/0x100
     nfs_follow_remote_path+0x16f/0x3e0 [nfs]
     nfs4_try_mount+0x6f/0xd0 [nfs]
     nfs_get_sb+0x269/0x400 [nfs]
     vfs_kern_mount+0x8a/0x1f0
     do_kern_mount+0x52/0x130
     do_mount+0x20a/0x260
     sys_mount+0x90/0xe0
     system_call_fastpath+0x16/0x1b

So just refresh fsid, as RFC3530 doesn't specify behavior
in case of rootfh changes fsid.
Signed-off-by: NVitaliy Gusev <gusev.vitaliy@nexenta.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

If we call xs_close(), we're in one of two situations:
 - Autoclose, which means we don't expect to resend a request
 - bind+connect failed, which probably means the port is in use
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org

When one of the two waits in nfs_commit_inode() is interrupted, it
returns a non-negative value, which causes nfs_wb_page() to think
that the operation was successful causing it to busy-loop rather
than exiting.
It also causes nfs_file_fsync() to incorrectly report the file as
being successfully committed to disk.

This patch fixes both problems by ensuring that we return an error
if the attempts to wait fail.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org

If we're only doing a single write, and there are no other unstable
writes being queued up, we might want to just flip to using a stable
write RPC call.
Reviewed-by: NNeilBrown <neilb@suse.de>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

RPC task RPC_TASK_QUEUED bit is set must be checked before trying to wake up
task rpc_killall_tasks() because task->tk_waitqueue can not be set (equal to
NULL).
Also, as Trond Myklebust mentioned, such approach (instead of checking
tk_waitqueue to NULL) allows us to "optimise away the call to
rpc_wake_up_queued_task() altogether for those
tasks that aren't queued".

Here is an example of dereferencing of tk_waitqueue equal to NULL:

CPU 0               	CPU 1				CPU 2
--------------------	---------------------	--------------------------
nfs4_run_open_task
rpc_run_task
rpc_execute
rpc_set_active
rpc_make_runnable
(waiting)
			rpc_async_schedule
			nfs4_open_prepare
			nfs_wait_on_sequence
						nfs_umount_begin
						rpc_killall_tasks
						rpc_wake_up_task
						rpc_wake_up_queued_task
						spin_lock(tk_waitqueue == NULL)
						BUG()
			rpc_sleep_on
			spin_lock(&q->lock)
			__rpc_sleep_on
			task->tk_waitqueue = q
Signed-off-by: NStanislav Kinsbursky <skinsbursky@openvz.org>
Cc: stable@kernel.org
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

remove redundant check.
Signed-off-by: NJinqiu Yang <crindy646@gmail.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

This fixes a race in which the task->tk_callback() puts the rpc_task
to sleep, setting a new callback. Under certain circumstances, the current
code may end up executing the task->tk_action before it gets round to the
callback.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org

Fix printk format build warning:

net/sunrpc/xprtrdma/verbs.c:1463: warning: format '%llx' expects type 'long long unsigned int', but argument 3 has type 'dma_addr_t'
Signed-off-by: NRandy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

'req' is dereferenced before checked for NULL.
The patch simply removes the check.

Signed-off-by: Jinqiu Yang<crindy646@gmail.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NStephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Commit 45a52a02 (NFS move nfs_client
initialization into nfs_get_client) introduces a new warning in
fs/nfs/idmap.c:

	‘struct rpc_timeout’ declared inside parameter list

Fix it by adding a forward declaration for the struct rpc_timeout
in include/linux/nfs_xdr.h
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Factor out some cut-and-paste code in options parsing.
Saves about 800 bytes on x86-64.
Signed-off-by: NRob Landley <rlandley@parallels.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Eliminate two mostly duplicate functions (nfs_parse_simple_hostname()
and nfs_parse_protected_hostname()) and instead just make the calling
function (nfs_parse_devname()) do everything.
Signed-off-by: NRob Landley <rlandley@parallels.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Account NFS direct-io reads and writes into Task I/O Accounting.
Do it before complition to handle aio.

NFS have unusual direct-io implementation,
thus accounting in generic code does not work.
Signed-off-by: NKonstantin Khlebnikov <khlebnikov@openvz.org>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Make the value in gm_upcall_enctypes just the enctype values.
This allows the values to be used more easily elsewhere.
Signed-off-by: NKevin Coffman <kwc@citi.umich.edu>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

When the rpc_memreg_strategy is 5, FRMR are used to map RPC data.
This mode uses an FRMR to map the RPC data, then invalidates
(i.e. unregisers) the data in xprt_rdma_free. These FRMR are used
across connections on the same mount, i.e. if the connection goes
away on an idle timeout and reconnects later, the FRMR are not
destroyed and recreated.

This creates a problem for transport errors because the WR that
invalidate an FRMR may be flushed (i.e. fail) leaving the
FRMR valid. When the FRMR is later used to map an RPC it will fail,
tearing down the transport and starting over. Over time, more and
more of the FRMR pool end up in the wrong state resulting in
seemingly random disconnects.

This fix keeps track of the FRMR state explicitly by setting it's
state based on the successful completion of a reg/inv WR. If the FRMR
is ever used and found to be in the wrong state, an invalidate WR
is prepended, re-syncing the FRMR state and avoiding the connection loss.
Signed-off-by: NTom Tucker <tom@ogc.us>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The RPCRDMA marshalling logic assumed that xdr->page_base was an
offset into the first page of xdr->page_list. It is in fact an
offset into the xdr->page_list itself, that is, it selects the
first page in the page_list and the offset into that page.

The symptom depended in part on the rpc_memreg_strategy, if it was
FRMR, or some other one-shot mapping mode, the connection would get
torn down on a base and bounds error. When the badly marshalled RPC
was retransmitted it would reconnect, get the error, and tear down the
connection again in a loop forever. This resulted in a hung-mount. For
the other modes, it would result in silent data corruption. This bug is
most easily reproduced by writing more data than the filesystem
has space for.

This fix corrects the page_base assumption and otherwise simplifies
the iov mapping logic.
Signed-off-by: NTom Tucker <tom@ogc.us>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The new behaviour is enabled using the new module parameter
'nfs4_disable_idmapping'.

Note that if the server rejects an unmapped uid or gid, then
the client will automatically switch back to using the idmapper.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

This will be required in order to switch uid/gid mapping back on if the
admin has tried to disable it.

Note that we also propagate NFS4ERR_BADNAME at the same time, in order to
work around a Linux server bug.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

...instead of the nfs_client.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Allowing stripe_unit==0 causes the client to crash later on
when dividing by zero.
Reported-by: NMarc Eshel <eshel@almaden.ibm.com>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Now that we have access to the pointer, clear it immediately after
the put, instead of in caller.
Signed-off-by: NFred Isaman <iisaman@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

This will make it possible to clear the lseg pointer in the same
function as it is put, instead of in the caller nfs_pageio_doio().
Signed-off-by: NFred Isaman <iisaman@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Allows the pnfs filelayout driver to write to the data servers.

Note that COMMIT to data servers will be implemented in a future
patch.  To avoid improper behavior, for the moment any WRITE to a data
server that would also require a COMMIT to the data server is sent
NFS_FILE_SYNC.
Signed-off-by: NAndy Adamson <andros@citi.umich.edu>
Signed-off-by: NDean Hildebrand <dhildeb@us.ibm.com>
Signed-off-by: NFred Isaman <iisaman@citi.umich.edu>
Signed-off-by: NMingyang Guo <guomingyang@nrchpc.ac.cn>
Signed-off-by: NOleg Drokin <green@linuxhacker.ru>
Signed-off-by: NRicardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NFred Isaman <iisaman@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Any WRITE compound directed to a data server needs to have the
GETATTR calls suppressed.
Signed-off-by: NFred Isaman <iisaman@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NAndy Adamson <andros@citi.umich.edu>
Signed-off-by: NBoaz Harrosh <bharrosh@panasas.com>
Signed-off-by: NDean Hildebrand <dhildeb@us.ibm.com>
Signed-off-by: NFred Isaman <iisaman@citi.umich.edu>
Signed-off-by: NJ. Bruce Fields <bfields@fieldses.org>
Signed-off-by: NMike Sager <sager@netapp.com>
Signed-off-by: NRicardo Labiaga <Ricardo.Labiaga@netapp.com>
Signed-off-by: NTao Guo <guotao@nrchpc.ac.cn>
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NFred Isaman <iisaman@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NFred Isaman <iisaman@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

We grab the lseg sent in from the doio function and attach it to
each struct nfs_write_data created.  This is how the lseg will be
sent to the layout driver.
Signed-off-by: NFred Isaman <iisaman@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Add callback that pnfs layout driver can use to do its own handling
of data server WRITE response.
Signed-off-by: NFred Isaman <iisaman@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Reorder nfs_write_rpcsetup, preparing for a pnfs entry point.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NFred Isaman <iisaman@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NFred Isaman <iisaman@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

If a data server is unavailable, go through MDS.

Mark the deviceid containing the data server as a negative cache entry.
Do not try to connect to any data server on a deviceid marked as a negative
cache entry. Mark any layout that tries to use the marked deviceid as failed.

Inodes with a layout marked as fails will not use the layout for I/O, and will
not perform any more layoutgets.
Inodes without a layout will still do layoutget, but the layout will get
marked immediately.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

No need for generic cache with only one user.
Keep a simple hash of deviceids in the filelayout driver.
Signed-off-by: NChristoph Hellwig <hch@infradead.org>
Acked-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Use our own async error handler.
Mark the layout as failed and retry i/o through the MDS on specified errors.

Update the mds_offset in nfs_readpage_retry so that a failed short-read retry
to a DS gets correctly resent through the MDS.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Attempt a pNFS file layout read by setting up the nfs_read_data struct and
calling nfs_initiate_read with the data server rpc client and the
filelayout rpc call ops.

Error handling is implemented in a subsequent patch.
Signed-off-by: NAndy Adamson <andros@citi.umich.edu>
Signed-off-by: NDean Hildebrand <dhildeb@us.ibm.com>
Signed-off-by: NFred Isaman <iisaman@citi.umich.edu>
Signed-off-by: NFred Isaman <iisaman@netapp.com>
Signed-off-by: NMingyang Guo <guomingyang@nrchpc.ac.cn>
Signed-off-by: NOleg Drokin <green@linuxhacker.ru>
Signed-off-by: NRicardo Labiaga <Ricardo.Labiaga@netapp.com>
Tested-by: NGuo Mingyang <guomingyang@nrchpc.ac.cn>
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Prepare for filelayout_read_pagelist with helper functions that find the correct
data server, filehandle, and offset.
Signed-off-by: NAndy Adamson <andros@citi.umich.edu>
Signed-off-by: NDean Hildebrand <dhildeb@us.ibm.com>
Signed-off-by: NFred Isaman <iisaman@netapp.com>
Signed-off-by: NMarc Eshel <eshel@almaden.ibm.com>
Signed-off-by: NMike Sager <sager@netapp.com>
Signed-off-by: NOleg Drokin <green@linuxhacker.ru>
Signed-off-by: NTao Guo <guotao@nrchpc.ac.cn>
Signed-off-by: NTigran Mkrtchyan <tigran@anahit.desy.de>
Signed-off-by: NTigran Mkrtchyan <tigran.mkrtchyan@desy.de>
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Introduce a data server set_client and init session following the
nfs4_set_client and  nfs4_init_session convention.

Once a new nfs_client is on the nfs_client_list, the nfs_client cl_cons_state
serializes access to creating an nfs_client struct with matching properties.

Use the new nfs_get_client() that initializes new clients.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>