The module (nfs2.ko) will be created in the same directory as nfs.ko and
will be automatically loaded the first time you try to mount over NFS v2.
Signed-off-by: NBryan Schumaker <bjschuma@netapp.com>
Signed-off-by: NTrond 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: NBryan Schumaker <bjschuma@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Keep track of the number of bytes read or written via buffered, direct, and
mem-mapped i/o for use by mdsthreshold size_io hints.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

RPC_TASK_SOFTCONN returns connection errors to the caller which allows the pNFS
file layout to quickly try the MDS or perhaps another DS.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Fix the following sparse warnings:

fs/nfs/direct.c:221:6: warning: symbol 'nfs_direct_readpage_release' was
not declared. Should it be static?
fs/nfs/read.c:38:43: warning: non-ANSI function declaration of function
'nfs_readhdr_alloc'
fs/nfs/objlayout/objio_osd.c:214:5: warning: symbol '__alloc_objio_seg'
was not declared. Should it be static?
Reported-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: Fred Isaman <iisaman@netapp.com>
Cc: Boaz Harrosh <bharrosh@panasas.com>

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

Move the error handling for nfs_generic_pagein() into a single function.
Ditto for nfs_generic_flush().
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: Fred Isaman <iisaman@netapp.com>

Remove unused variables, and reformat some code.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: Fred Isaman <iisaman@netapp.com>

This also has the advantage that it allows directio to use pnfs.
Signed-off-by: NFred Isaman <iisaman@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Factors out the code that will need to change when directio
starts using these code paths.  This will allow directio to use
the generic pagein and flush routines
Signed-off-by: NFred Isaman <iisaman@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Decouple nfs_pgio_header and nfs_read_data, and have (possibly
multiple) nfs_read_datas each take a refcount on nfs_pgio_header.

For the moment keeps nfs_read_header as a way to preallocate a single
nfs_read_data with the nfs_pgio_header.  The code doesn't need this,
and would be prettier without, but given the amount of churn I am
already introducing I didn't want to play with tuning new mempools.

This also fixes bug in pnfs_ld_handle_read_error.  In the case of
desc->pg_bsize < PAGE_CACHE_SIZE, the pages list was empty, causing
replay attempt to do nothing.
Signed-off-by: NFred Isaman <iisaman@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Both nfs_read_data and nfs_write_data devote several fields which
can be combined into a single shared struct.
Signed-off-by: NFred Isaman <iisaman@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

In order to avoid duplicating all the data in nfs_read_data whenever we
split it up into multiple RPC calls (either due to a short read result
or due to rsize < PAGE_SIZE), we split out the bits that are the same
per RPC call into a separate "header" structure.

The goal this patch moves towards is to have a single header
refcounted by several rpc_data structures.  Thus, want to always refer
from rpc_data to the header, and not the other way.  This patch comes
close to that ideal, but the directio code currently needs some
special casing, isolated in the nfs_direct_[read_write]hdr_release()
functions.  This will be dealt with in a future patch.
Signed-off-by: NFred Isaman <iisaman@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Make it consistent with nfs_initiate_commit.
Signed-off-by: NFred Isaman <iisaman@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

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>