We need to use the same credential as was used for the layoutget
and/or layoutcommit operations.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Ensure that we use the same credential for layoutget, layoutcommit and
layoutreturn.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

If state recovery fails with an ESTALE or a ENOENT, then we shouldn't
keep retrying. Instead, mark the stateid as being invalid and
fail the I/O with an EIO error.
For other operations such as POSIX and BSD file locking, truncate
etc, fail with an EBADF to indicate that this file descriptor is no
longer valid.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

In order to be able to safely return the layout in nfs4_proc_setattr,
we need to block new uses of the layout, wait for all outstanding
users of the layout to complete, commit the layout and then return it.

This patch adds a helper in order to do all this safely.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: Boaz Harrosh <bharrosh@panasas.com>

Note that clearing NFS_INO_LAYOUTCOMMIT is tricky, since it requires
you to also clear the NFS_LSEG_LAYOUTCOMMIT bits from the layout
segments.
The only two sites that need to do this are the ones that call
pnfs_return_layout() without first doing a layout commit.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: NBenny Halevy <bhalevy@tonian.com>
Cc: stable@vger.kernel.org

We need to clear the NFS_LSEG_LAYOUTCOMMIT bits atomically with the
NFS_INO_LAYOUTCOMMIT bit, otherwise we may end up with situations
where the two are out of sync.
The first half of the problem is to ensure that pnfs_layoutcommit_inode
clears the NFS_LSEG_LAYOUTCOMMIT bit through pnfs_list_write_lseg.
We still need to keep the reference to those segments until the RPC call
is finished, so in order to make it clear _where_ those references come
from, we add a helper pnfs_list_write_lseg_done() that cleans up after
pnfs_list_write_lseg.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: NBenny Halevy <bhalevy@tonian.com>
Cc: stable@vger.kernel.org

The client will currently try LAYOUTGETs forever if a server is returning
NFS4ERR_LAYOUTTRYLATER or NFS4ERR_RECALLCONFLICT - even if the client no
longer needs the layout (ie process killed, unmounted).

This patch uses the DS timeout value (module parameter 'dataserver_timeo'
via rpc layer) to set an upper limit of how long the client tries LATOUTGETs
in this situation.  Once the timeout is reached, IO is redirected to the MDS.

This also changes how the client checks if a layout is on the clp list
to avoid a double list_add.
Signed-off-by: NWeston Andros Adamson <dros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Pass the directio request on pageio_init to clean up the API.

Percolate pg_dreq from original nfs_pageio_descriptor to the
pnfs_{read,write}_done_resend_to_mds and use it on respective
call to nfs_pageio_init_{read,write} on the newly created
nfs_pageio_descriptor.

Reproduced by command:
 mount -o vers=4.1 server:/ /mnt
 dd bs=128k count=8 if=/dev/zero of=/mnt/dd.out oflag=direct

BUG: unable to handle kernel NULL pointer dereference at 0000000000000028
IP: [<ffffffffa021a3a8>] atomic_inc+0x4/0x9 [nfs]
PGD 34786067 PUD 34794067 PMD 0
Oops: 0002 [#1] SMP
Modules linked in: nfs_layout_nfsv41_files nfsv4 nfs nfsd lockd nfs_acl auth_rpcgss exportfs sunrpc btrfs zlib_deflate libcrc32c ipv6 autofs4
CPU 1
Pid: 259, comm: kworker/1:2 Not tainted 3.8.0-rc6 #2 Bochs Bochs
RIP: 0010:[<ffffffffa021a3a8>]  [<ffffffffa021a3a8>] atomic_inc+0x4/0x9 [nfs]
RSP: 0018:ffff880038f8fa68  EFLAGS: 00010206
RAX: ffffffffa021a6a9 RBX: ffff880038f8fb48 RCX: 00000000000a0000
RDX: ffffffffa021e616 RSI: ffff8800385e9a40 RDI: 0000000000000028
RBP: ffff880038f8fa68 R08: ffffffff81ad6720 R09: ffff8800385e9510
R10: ffffffffa0228450 R11: ffff880038e87418 R12: ffff8800385e9a40
R13: ffff8800385e9a70 R14: ffff880038f8fb38 R15: ffffffffa0148878
FS:  0000000000000000(0000) GS:ffff88003e400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 0000000000000028 CR3: 0000000034789000 CR4: 00000000000006e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process kworker/1:2 (pid: 259, threadinfo ffff880038f8e000, task ffff880038302480)
Stack:
 ffff880038f8fa78 ffffffffa021a6bf ffff880038f8fa88 ffffffffa021bb82
 ffff880038f8fae8 ffffffffa021f454 ffff880038f8fae8 ffffffff8109689d
 ffff880038f8fab8 ffffffff00000006 0000000000000000 ffff880038f8fb48
Call Trace:
 [<ffffffffa021a6bf>] nfs_direct_pgio_init+0x16/0x18 [nfs]
 [<ffffffffa021bb82>] nfs_pgheader_init+0x6a/0x6c [nfs]
 [<ffffffffa021f454>] nfs_generic_pg_writepages+0x51/0xf8 [nfs]
 [<ffffffff8109689d>] ? mark_held_locks+0x71/0x99
 [<ffffffffa0148878>] ? rpc_release_resources_task+0x37/0x37 [sunrpc]
 [<ffffffffa021bc25>] nfs_pageio_doio+0x1a/0x43 [nfs]
 [<ffffffffa021be7c>] nfs_pageio_complete+0x16/0x2c [nfs]
 [<ffffffffa02608be>] pnfs_write_done_resend_to_mds+0x95/0xc5 [nfsv4]
 [<ffffffffa0148878>] ? rpc_release_resources_task+0x37/0x37 [sunrpc]
 [<ffffffffa028e27f>] filelayout_reset_write+0x8c/0x99 [nfs_layout_nfsv41_files]
 [<ffffffffa028e5f9>] filelayout_write_done_cb+0x4d/0xc1 [nfs_layout_nfsv41_files]
 [<ffffffffa024587a>] nfs4_write_done+0x36/0x49 [nfsv4]
 [<ffffffffa021f996>] nfs_writeback_done+0x53/0x1cc [nfs]
 [<ffffffffa021fb1d>] nfs_writeback_done_common+0xe/0x10 [nfs]
 [<ffffffffa028e03d>] filelayout_write_call_done+0x28/0x2a [nfs_layout_nfsv41_files]
 [<ffffffffa01488a1>] rpc_exit_task+0x29/0x87 [sunrpc]
 [<ffffffffa014a0c9>] __rpc_execute+0x11d/0x3cc [sunrpc]
 [<ffffffff810969dc>] ? trace_hardirqs_on_caller+0x117/0x173
 [<ffffffffa014a39f>] rpc_async_schedule+0x27/0x32 [sunrpc]
 [<ffffffffa014a378>] ? __rpc_execute+0x3cc/0x3cc [sunrpc]
 [<ffffffff8105f8c1>] process_one_work+0x226/0x422
 [<ffffffff8105f7f4>] ? process_one_work+0x159/0x422
 [<ffffffff81094757>] ? lock_acquired+0x210/0x249
 [<ffffffffa014a378>] ? __rpc_execute+0x3cc/0x3cc [sunrpc]
 [<ffffffff810600d8>] worker_thread+0x126/0x1c4
 [<ffffffff8105ffb2>] ? manage_workers+0x240/0x240
 [<ffffffff81064ef8>] kthread+0xb1/0xb9
 [<ffffffff81064e47>] ? __kthread_parkme+0x65/0x65
 [<ffffffff815206ec>] ret_from_fork+0x7c/0xb0
 [<ffffffff81064e47>] ? __kthread_parkme+0x65/0x65
Code: 00 83 38 02 74 12 48 81 4b 50 00 00 01 00 c7 83 60 07 00 00 01 00 00 00 48 89 df e8 55 fe ff ff 5b 41 5c 5d c3 66 90 55 48 89 e5 <f0> ff 07 5d c3 55 48 89 e5 f0 ff 0f 0f 94 c0 84 c0 0f 95 c0 0f
RIP  [<ffffffffa021a3a8>] atomic_inc+0x4/0x9 [nfs]
 RSP <ffff880038f8fa68>
CR2: 0000000000000028
Signed-off-by: NBenny Halevy <bhalevy@tonian.com>
Cc: stable@kernel.org [>= 3.6]
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The current code in pnfs_destroy_all_layouts() assumes that removing
the layout from the server->layouts list is sufficient to make it
invisible to other processes. This ignores the fact that most
users access the layout through the nfs_inode->layout...
There is further breakage due to lack of reference counting of the
layouts, meaning that the whole thing Oopses at the drop of a hat.

The code in initiate_bulk_draining() is almost correct, and can be
used as a model for pnfs_destroy_all_layouts(), so move that
code to pnfs.c, and refactor the code to allow us to choose between
a single filesystem bulk recall, and a recall of all layouts.
Also note that initiate_bulk_draining() currently calls iput() while
holding locks. Fix that too.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org

The layout will be set unusable if LAYOUTGET fails. Is it reasonable to
increase the refcount iff LAYOUTGET fails the first time?
Signed-off-by: NYanchuan Nian <ycnian@gmail.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@vger.kernel.org [>= 3.7]

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

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

The new layout pointer in pnfs_find_alloc_layout() may be NULL because of
out of memory. we must do some check work, otherwise pnfs_free_layout_hdr()
will go wrong because it can not deal with a NULL pointer.
Signed-off-by: NYanchuan Nian <ycnian@gmail.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

For buffer read, use offst-to-isize.

For direct read, use dreq->bytes_left.
Signed-off-by: NPeng Tao <tao.peng@emc.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

For buffer write, block layout client scan inode mapping to find
next hole and use offset-to-hole as layoutget length. Object
layout client uses offset-to-isize as layoutget length.

For direct write, both block layout and object layout use dreq->bytes_left.
Signed-off-by: NPeng Tao <tao.peng@emc.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Split it into two functions, one which checks if layoutgets are blocked,
and one which checks if the layout stateid has expired.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Clamp the layout barrier sequence id to the current sequence id
minus the maximum number of outstanding layoutget requests.

Also ensure that we correctly initialise lo->plh_barrier if there are
no layout segments associated to this layout header.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

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

...and fix a bug in pnfs_set_layout_stateid.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

...and add a helper function.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

If the list of layout segments is empty, we must unconditionally set
the layout stateid.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

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

Failure of the layoutreturn allocation fails is not a good reason to
mark the pnfs_layout_hdr as having failed a layoutget or i/o. Just
exit cleanly.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

It serves no purpose that the test for whether or not we have valid
layout segments doesn't already serve.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Once all the affected layout segments have been freed up, clear the
NFS_LAYOUT_BULK_RECALL flag so that we can reuse the pnfs_layout_hdr
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

We already have a mechanism for blocking LAYOUTGET by means of the
plh_block_lgets counter. The only "service" that NFS_LAYOUT_DESTROYED
provides at this point is to block layoutget once the layout segment
list is empty, which basically means that you have to wait until
the pnfs_layout_hdr is destroyed before you can do pNFS on that file
again.

This patch enables the reuse of the pnfs_layout_hdr if the layout
segment list is empty.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

...and ditto for pnfs_free_layout_hdr()
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

These are all in static declared functions that are called only once.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Ensure that the reference count for pnfs_layout_hdr reverts to the
original value after a call to pnfs_layout_remove_lseg().

Note that the caller is expected to hold a reference to the struct
pnfs_layout_hdr.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

There is no longer a need to use pnfs_free_lseg_list(). Just call
pnfs_free_lseg() directly.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Move the code into pnfs_free_layout_hdr(), and add checks to
get_layout_by_fh_locked to ensure that they don't reference a layout
that is being freed.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

None of the existing pNFS layout drivers seem to require the inode
to be locked while they free the layout header.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Each layout segment already holds a reference to the pnfs_layout_hdr,
so there is no need to hold an extra reference that is released once
the last layout segment is freed.

Ensure that pnfs_find_alloc_layout() always returns a reference
to the pnfs_layout_hdr, which will be matched by the final call to
pnfs_put_layout_hdr() in pnfs_update_layout().
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The latter name is more descriptive of the actual function.
Also rename pnfs_insert_layout to pnfs_layout_insert_lseg.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Instead of resetting the inode MDS threshold counters when we mark
the layout for destruction, do it as part of freeing the layout.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

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: NTrond Myklebust <Trond.Myklebust@netapp.com>

If pnfs_layout_io_test_failed() authorises a retry of the failed layoutgets,
we should clear the existing layout segments so that we start afresh. Do
this in pnfs_layout_io_set_failed().
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

We want to cache the pnfs_layout_hdr after a layoutget or i/o
failure so that pnfs_update_layout() can find it and know when
it is time to retry.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

If we exit after the call to pnfs_find_alloc_layout(), we have to ensure
that we put the struct pnfs_layout_hdr.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

If we had to fall back to read/write through MDS, then assume that we should
retry pNFS after a suitable timeout period.
The following patch sets a timeout of 2 minutes.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>