Cc: <stable@vger.kernel.org>
Signed-off-by: NFred Isaman <iisaman@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Remove all #inclusions of asm/system.h preparatory to splitting and killing
it.  Performed with the following command:

perl -p -i -e 's!^#\s*include\s*<asm/system[.]h>.*\n!!' `grep -Irl '^#\s*include\s*<asm/system[.]h>' *`
Signed-off-by: NDavid Howells <dhowells@redhat.com>

This is an NFS v4 specific operation, so it belongs in the NFS v4 code
and not the generic client.
Signed-off-by: NBryan Schumaker <bjschuma@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Move more pnfs-isms out of the generic commit code.

Bugfixes:

- filelayout_scan_commit_lists doesn't need to get/put the lseg.
  In fact since it is run under the inode->i_lock, the lseg_put()
  can deadlock.

- Ensure that we distinguish between what needs to be done for
  commit-to-data server and what needs to be done for commit-to-MDS
  using the new flag PG_COMMIT_TO_DS. Otherwise we may end up calling
  put_lseg() on a bucket for a struct nfs_page that got written
  through the MDS.

- Fix a case where we were using list_del() on an nfs_page->wb_list
  instead of list_del_init().

- filelayout_initiate_commit needs to call filelayout_commit_release
  on error instead of the mds_ops->rpc_release(). Otherwise it won't
  clear the commit lock.

Cleanups:

- Let the files layout manage the commit lists for the pNFS case.
  Don't expose stuff like pnfs_choose_commit_list, and the fact
  that the commit buckets hold references to the layout segment
  in common code.

- Cast out the put_lseg() calls for the struct nfs_read/write_data->lseg
  into the pNFS layer from whence they came.

- Let the pNFS layer manage the NFS_INO_PNFS_COMMIT bit.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: Fred Isaman <iisaman@netapp.com>

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

pNFS-specific code belongs in the pnfs layer. It should not be
hijacking generic NFS read or write code paths.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

We don't need a mempool in order to guarantee reliable NFS read performance.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Don't rely on the PageError flag to tell us if one of the partial reads of
the page failed. Instead, replace that with a dedicated flag in the
struct nfs_page.

Then clean out redundant uses of the PageError flag: the VM no longer
checks it for reads.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The generic file read code does that for us anyway.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

It can trivially be replaced with rpc_restart_call_prepare.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

For pnfs pagelist read failure, we need to pg_recoalesce and resend IO to
mds.
Signed-off-by: NPeng Tao <peng_tao@emc.com>
Signed-off-by: NJim Rees <rees@umich.edu>
Cc: stable@kernel.org [3.0]
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

just dentry, please...
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

Use nfs_pageio_reset_read_mds and nfs_pageio_reset_write_mds instead of
completely reinitialising the struct nfs_pageio_descriptor.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

...and ensure that we recoalese to take into account differences in
block sizes when falling back to read through the MDS.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Instead of looking up the rsize and wsize, the routines that generate the
RPC requests should really be using the pg_bsize, since that is what we
use when deciding whether or not to coalesce write requests...
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

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

...and do the same for nfs_flush_multi/one.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Signed-off-by: NPeng Tao <peng_tao@emc.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Split them up into two parts: one which sets up the struct nfs_read/write_data,
the other which sets up the actual RPC call or pNFS call.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Ask for whole file layouts. Until support for layout segments is fully
supported in the file layout code, discard non-whole file layouts.
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: NTrond Myklebust <Trond.Myklebust@netapp.com>

Ensure that we always get a layout before setting up the i/o request.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

We need to ensure that the layouts are set up before we can decide to
coalesce requests. To do so, we want to further split up the struct
nfs_pageio_descriptor operations into an initialisation callback, a
coalescing test callback, and a 'do i/o' callback.

This patch cleans up the existing callback methods before adding the
'initialisation' callback.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Use common code for pnfs_pageio_init_{read,write} and use
a common generic pg_test function.

Note that this function always assumes the the layout driver's
pg_test method is implemented.

[Fix BUG]
Signed-off-by: NBoaz Harrosh <bharrosh@panasas.com>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>

Add offset and count parameters to pnfs_update_layout and use them to get
the layout in the pageio path.

Order cache layout segments in the following order:
* offset (ascending)
* length (descending)
* iomode (RW before READ)

Test byte range against the layout segment in use in pnfs_{read,write}_pg_test
so not to coalesce pages not using the same layout segment.

[fix lseg ordering]
[clean up pnfs_find_lseg lseg arg]
[remove unnecessary FIXME]
[fix ordering in pnfs_insert_layout]
[clean up pnfs_insert_layout]
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>

Currently, writebacks may end up recursing back into the filesystem due to
GFP_KERNEL direct reclaims in the pnfs subsystem.
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>

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>

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>

Separate the rpc run portion of nfs_read_rpcsetup into a new function
nfs_initiate_read that is called for normal NFS I/O.

Add a pNFS read_pagelist function that is called instead of nfs_intitate_read
for pNFS reads.
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: NFred Isaman <iisaman@netapp.com>
Signed-off-by: NMike Sager <sager@netapp.com>
Signed-off-by: NMingyang Guo <guomingyang@nrchpc.ac.cn>
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: NTrond Myklebust <Trond.Myklebust@netapp.com>

Move the pnfs_update_layout call location to nfs_pageio_do_add_request().
Grab the lseg sent in the doio function to nfs_read_rpcsetup and attach
it to each nfs_read_data so it can be sent to the layout driver.
Signed-off-by: NAndy Adamson <andros@netapp.com>
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: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NBoaz Harrosh <bharrosh@panasas.com>
Signed-off-by: NOleg Drokin <green@linuxhacker.ru>
Signed-off-by: NTao Guo <guotao@nrchpc.ac.cn>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Add a pg_test layout driver hook which is used to avoid coelescing I/O across
layout stripes.
Signed-off-by: NAndy Adamson <andros@netapp.com>
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: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NBoaz Harrosh <bharrosh@panasas.com>
Signed-off-by: NOleg Drokin <green@linuxhacker.ru>
Signed-off-by: NTao Guo <guotao@nrchpc.ac.cn>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

When a nfs_page is freed, nfs_free_request is called which also calls
nfs_clear_request to clean out the lock and open contexts and free the
pagecache page.

However, a couple of places in the nfs code call nfs_clear_request
themselves. What happens here if the refcount on the request is still high?
We'll be releasing contexts and freeing pointers while the request is
possibly still in use.

Remove those bare calls to nfs_clear_context. That should only be done when
the request is being freed.

Note that when doing this, we need to watch out for tests of req->wb_page.
Previously, nfs_set_page_tag_locked() and nfs_clear_page_tag_locked()
would check the value of req->wb_page to figure out if the page is mapped
into the nfsi->nfs_page_tree. We now indicate the page is mapped using
the new bit PG_MAPPED in req->wb_flags .
Reported-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

At the start of the io paths, try to grab the relevant layout
information.  This will initiate the inode's layout cache, but
stubs ensure the cache stays empty.
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NDean Hildebrand <dhildebz@umich.edu>
Signed-off-by: NMarc Eshel <eshel@almaden.ibm.com>
Signed-off-by: NTao Guo <guotao@nrchpc.ac.cn>
Signed-off-by: NRicardo Labiaga <ricardo.labiaga@netapp.com>
Signed-off-by: NBoaz Harrosh <bharrosh@panasas.com>
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>

Having to explicitly initialize sr_slotid to NFS4_MAX_SLOT_TABLE
resulted in numerous bugs.  Keeping the current slot as a pointer
to the slot table is more straight forward and robust as it's
implicitly set up to NULL wherever the seq_res member is initialized
to zeroes.
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

This patch fixes bugzilla entry 14501:
  https://bugzilla.kernel.org/show_bug.cgi?id=14501Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

In anticipation of the day when we have per-filesystem sessions, and also
in order to allow the session to change in the event of a filesystem
migration event.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

There is no danger of deadlock should the allocation trigger page
writeback.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>