Fix the namespace pollution issue.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The "invalid layout" class of errors is handled by destroying the layout and
getting a new layout from the server.  Currently, the layout must be
destroyed before a new layout can be obtained.

This means that all references (e.g.lsegs) to the "to be destroyed" layout
header must be dropped before it can be destroyed. This in turn means waiting
for all in flight RPC's using the old layout as well as draining the data
server session slot table wait queue.

Set the NFS_LAYOUT_INVALID flag to redirect I/O to the MDS while waiting for
the old layout to be destroyed.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

When the last DS io is processed, the data server client record will be
freed.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

This prevents the use of any layout for i/o that references the deviceid.
I/O is redirected through the MDS.

Redirect the unhandled failed I/O to the MDS without marking either the
layout or the deviceid invalid.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Set the recovery parameters for data servers.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Move the invalid deviceid test into nfs4_fl_prepare_ds, called by the
filelayout read, write, and commit routines. NFS4_DEVICE_ID_NEG_ENTRY
is no longer needed.
Remove redundant printk's - filelayout_mark_devid_invalid prints a KERN_WARNING.

An invalid device prevents pNFS io.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

It is COMMIT that is handled the most differently between
the paged and direct paths.  Create a structure that encapsulates
everything either path needs to know about the commit state.

We could use void to hide some of the layout driver stuff, but
Trond suggests pulling it out to ensure type checking, given the
huge changes being made, and the fact that it doesn't interfere
with other drivers.
Signed-off-by: NFred Isaman <iisaman@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Also create a commit_info structure to hold the bucket array and push
it up from the lseg to the layout where it really belongs.

While we are at it, fix a refcounting bug due to an (incorrect)
implicit assumption that filelayout_scan_ds_commit_list always
completely emptied the src list.

This clarifies refcounting, removes the ugly find_only_write_lseg
functions, and pushes the file layout commit code along on the path to
supporting multiple lsegs.
Signed-off-by: NFred Isaman <iisaman@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

The radix tree is only being used to compile lists of reqs needing commit.
It is simpler to just put the reqs directly into a list.
Signed-off-by: NFred Isaman <iisaman@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Mark all deviceids established under an expired MDS clientid as invalid.
Stop all new i/o through DS and send through the MDS.
Don't use any new LAYOUTGETs that use the invalid deviceid. Purge all layouts
established under the expired MDS clientid.
Remove the MDS clientid deviceid and data servers reference
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

This parses and stores all addresses associated with each data server,
laying the groundwork for supporting multipath to data servers.

 - Skips over addresses that cannot be parsed (ie IPv6 addrs if v6 is not
   enabled).  Only fails if none of the addresses are recognizable
 - Currently only uses the first address that parsed cleanly
 - Tested against pynfs server (modified to support multipath)
Signed-off-by: NWeston Andros Adamson <dros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Handle ipv6 remote addresses from GETDEVICEINFO

 - supports netid "tcp" for ipv4 and "tcp6" for ipv6 as rfc 5665 specifies
 - added ds_remotestr to avoid having to handle different AFs in every dprintk
 - tested against pynfs 4.1 server, submitting ipv6 support patch to pynfs
 - tested with IPv6 disabled, it compiles cleanly and relies on rpc_pton to
   refuse to accept IPv6 addresses
Signed-off-by: NWeston Andros Adamson <dros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Use the pnfs_layoutdriver_type both as a qualifier for the deviceid,
distinguishing deviceid from different layout types on the server,
and for freeing the layout-driver allocated structure containing the
nfs4_deviceid_node.

[BUG in _deviceid_purge_client]
[layout_driver MUST set free_deviceid_node if using dev-cache]
[let ver < 4.1 compile]
Signed-off-by: NBoaz Harrosh <bharrosh@panasas.com>
[removed EXPORT_SYMBOL_GPL(nfs4_deviceid_purge_client)]
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>

Move deviceid cache from the pnfs files layout driver to the
generic layer in preparation for the objects layout driver.
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>

deviceids are unique per server, per layout type.
Therefore, in the global cache in the files layout driver
deviceids from different servers may clash so we need
to qualify them with a struct nfs_client that represents
the nfs server that returned the deviceid.

Introduced in 2.6.39 commit ea8eecdd
"NFSv4.1 move deviceid cache to filelayout driver"
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>

Fixes generated by 'codespell' and manually reviewed.
Signed-off-by: NLucas De Marchi <lucas.demarchi@profusion.mobi>

Create a preallocated list header to hold nfs_pages for each
non-MDS COMMIT destination.  Note this is not necessarily each DS,
but is basically each <DS, fh> pair.
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>

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>

Implement the driver's io_ops->alloc_lseg and free_lseg functions,
which integrate into the deviceid cache and calls out to
nfs4_proc_getdeviceinfo when necessary.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NDean Hildebrand <dhildebz@umich.edu>
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: NRicardo Labiaga <ricardo.labiaga@netapp.com>
Signed-off-by: NTao Guo <guotao@nrchpc.ac.cn>
Signed-off-by: NBoaz Harrosh <bharrosh@panasas.com>
Signed-off-by: NFred Isaman <iisaman@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>