nfs41_sequence_free_slot can be called multiple times on SEQUENCE operation
errors.
No reason to inline nfs4_restart_rpc
Reported-by: NTrond Myklebust <trond.myklebust@netapp.com>

nfs_writeback_done and nfs_readpage_retry call nfs4_restart_rpc outside the
error handler, and the slot is not freed prior to restarting in the rpc_prepare
state during session reset.

Fix this by moving the call to nfs41_sequence_free_slot from the error
path of nfs41_sequence_done into nfs4_restart_rpc, and by removing the test
for NFS4CLNT_SESSION_SETUP.
Always free slot and goto the rpc prepare state on async errors.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

We can't call nfs_readdata_release()/nfs_writedata_release() without
first initialising and referencing args.context. Doing so inside
nfs_direct_read_schedule_segment()/nfs_direct_write_schedule_segment()
causes an Oops.

We should rather be calling nfs_readdata_free()/nfs_writedata_free() in
those cases.

Looking at the O_DIRECT code, the "struct nfs_direct_req" is already
referencing the nfs_open_context for us. Since the readdata and writedata
structures carry a reference to that, we can simplify things by getting rid
of the extra nfs_open_context references, so that we can replace all
instances of nfs_readdata_release()/nfs_writedata_release().
Reported-by: NCatalin Marinas <catalin.marinas@arm.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Tested-by: NCatalin Marinas <catalin.marinas@arm.com>
Cc: stable@kernel.org
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

* Remove smp_lock.h from files which don't need it (including some headers!)
* Add smp_lock.h to files which do need it
* Make smp_lock.h include conditional in hardirq.h
  It's needed only for one kernel_locked() usage which is under CONFIG_PREEMPT

  This will make hardirq.h inclusion cheaper for every PREEMPT=n config
  (which includes allmodconfig/allyesconfig, BTW)
Signed-off-by: NAlexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

[nfs41: change nfs4_restart_rpc argument]
[nfs41: check for session not minorversion]
[nfs41: trigger the state manager for session reset]
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
[always define nfs4_restart_rpc]
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Implement the read rpc_call_prepare method for
asynchronuos nfs rpcs, call nfs41_setup_sequence from
respective rpc_call_validate_args methods.

Call nfs4_sequence_done from respective rpc_call_done methods.

Note that we need to pass a pointer to the nfs_server in calls data
for passing on to nfs4_sequence_done.
Signed-off-by: NAndy Adamson <andros@netapp.com>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
[pnfs: client data server write validate and release]
Signed-off-by: NAndy Adamson <andros@umich.edu>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
[move the nfs4_sequence_free_slot call in nfs_readpage_retry from]
[nfs41: separate free slot from sequence done]
[remove nfs_readargs.nfs_server, use calldata->inode instead]
Signed-off-by: NAndy Adamson <andros@umich.edu>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
[nfs41: Support sessions with O_DIRECT]
Signed-off-by: NDean Hildebrand <dhildeb@us.ibm.com>
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
[nfs41: nfs4_sequence_free_slot use nfs_client for data server]
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>

Initialize nfs4_sequence_res sr_slotid to NFS4_MAX_SLOT_TABLE.

[was nfs41: sequence res use slotid]
Signed-off-by: NAndy Adamson <andros@netapp.com>
[pulled definition of struct nfs4_sequence_res.sr_slotid to here]
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Store pages from an NFS inode into the cache data storage object associated
with that inode.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Acked-by: NSteve Dickson <steved@redhat.com>
Acked-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: NAl Viro <viro@zeniv.linux.org.uk>
Tested-by: NDaire Byrne <Daire.Byrne@framestore.com>

Read pages from an FS-Cache data storage object representing an inode into an
NFS inode.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Acked-by: NSteve Dickson <steved@redhat.com>
Acked-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: NAl Viro <viro@zeniv.linux.org.uk>
Tested-by: NDaire Byrne <Daire.Byrne@framestore.com>

nfs_readpage_async() needs to be non-static so that it can be used as a
fallback for the local on-disk caching should an EIO crop up when reading the
cache.
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Acked-by: NSteve Dickson <steved@redhat.com>
Acked-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: NAl Viro <viro@zeniv.linux.org.uk>
Tested-by: NDaire Byrne <Daire.Byrne@framestore.com>

aops->readpages() and its NFS helper readpage_async_filler() will only
be called to do readahead I/O for newly allocated pages. So it's not
necessary to test for the always 0 dirty/uptodate page flags.

The removal of nfs_wb_page() call also fixes a readahead bug: the NFS
readahead has been synchronous since 2.6.23, because that call will
clear PG_readahead, which is the reminder for asynchronous readahead.

More background: the PG_readahead page flag is shared with PG_reclaim,
one for read path and the other for write path. clear_page_dirty_for_io()
unconditionally clears PG_readahead to prevent possible readahead residuals,
assuming itself to be always called in the write path. However, NFS is one
and the only exception in that it _always_ calls clear_page_dirty_for_io()
in the read path, i.e. for readpages()/readpage().

Cc: Trond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: NWu Fengguang <wfg@linux.intel.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

__FUNCTION__ is gcc-specific, use __func__
Signed-off-by: NHarvey Harrison <harvey.harrison@gmail.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

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

In the case of readpage() we need to ensure that the pages get unlocked,
and that the error is flagged.

In the case of O_DIRECT, we need to ensure that the pages are all released.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

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

Ignoring the return value from nfs_pageio_add_request can cause deadlocks.

In read path:
  call nfs_pageio_add_request from readpage_async_filler
  assume at this point that there are requests already in desc, that
    can't be merged with the current request.
  so nfs_pageio_doio is fired up to clear out desc.
  assume something goes wrong in setting up the io, so desc->pg_error is set.
  This causes nfs_pageio_add_request to return 0, *WITHOUT* adding the original
    request.
  BUT, since return code is ignored, readpage_async_filler assumes it has
    been added, and does nothing further, leaving page locked.
  do_generic_mapping_read will eventually call lock_page, resulting in deadlock

In write path:
  page is marked dirty by generic_perform_write
  nfs_writepages is called
  call nfs_pageio_add_request from nfs_page_async_flush
  assume at this point that there are requests already in desc, that
    can't be merged with the current request.
  so nfs_pageio_doio is fired up to clear out desc.
  assume something goes wrong in setting up the io, so desc->pg_error is set.
  This causes nfs_page_async_flush to return 0, *WITHOUT* adding the original
    request, yet marking the request as locked (PG_BUSY) and in writeback,
    clearing dirty marks.
  The next time a write is done to the page, deadlock will result as
    nfs_write_end calls nfs_update_request
Signed-off-by: NFred Isaman <iisaman@citi.umich.edu>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Now that we've tightened up the locking rules for RPC queue wakeups, we can
remove the RCU-safe kfree calls...
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

We want to ensure that rpc_call_ops that involve mntput() are run on nfsiod
rather than on rpciod, so that they don't deadlock when the resulting
umount calls rpc_shutdown_client(). Hence we specify that read, write and
commit calls must complete on nfsiod.
Ditto for NFSv4 open, lock, locku and close asynchronous calls.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

We can't allow rpc callback functions like task->tk_ops->rpc_call_prepare()
and task->tk_ops->rpc_call_done() to call mntput() in any way, since
that will cause a deadlock when the call to rpc_shutdown_client() attempts
to wait on 'task' to complete.

We can avoid the above deadlock by moving calls to mntput to
task->tk_ops->rpc_release() callback, since at that time the task will be
marked as completed, and so rpc_shutdown_client won't attempt to wait on
it.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Simplify page cache zeroing of segments of pages through 3 functions

zero_user_segments(page, start1, end1, start2, end2)

        Zeros two segments of the page. It takes the position where to
        start and end the zeroing which avoids length calculations and
	makes code clearer.

zero_user_segment(page, start, end)

        Same for a single segment.

zero_user(page, start, length)

        Length variant for the case where we know the length.

We remove the zero_user_page macro. Issues:

1. Its a macro. Inline functions are preferable.

2. The KM_USER0 macro is only defined for HIGHMEM.

   Having to treat this special case everywhere makes the
   code needlessly complex. The parameter for zeroing is always
   KM_USER0 except in one single case that we open code.

Avoiding KM_USER0 makes a lot of code not having to be dealing
with the special casing for HIGHMEM anymore. Dealing with
kmap is only necessary for HIGHMEM configurations. In those
configurations we use KM_USER0 like we do for a series of other
functions defined in highmem.h.

Since KM_USER0 is depends on HIGHMEM the existing zero_user_page
function could not be a macro. zero_user_* functions introduced
here can be be inline because that constant is not used when these
functions are called.

Also extract the flushing of the caches to be outside of the kmap.

[akpm@linux-foundation.org: fix nfs and ntfs build]
[akpm@linux-foundation.org: fix ntfs build some more]
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Cc: Steven French <sfrench@us.ibm.com>
Cc: Michael Halcrow <mhalcrow@us.ibm.com>
Cc: <linux-ext4@vger.kernel.org>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Anton Altaparmakov <aia21@cantab.net>
Cc: Mark Fasheh <mark.fasheh@oracle.com>
Cc: David Chinner <dgc@sgi.com>
Cc: Michael Halcrow <mhalcrow@us.ibm.com>
Cc: Steven French <sfrench@us.ibm.com>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

use NFS_I(inode)->flags instead
Signed-off-by: NBenny Halevy <bhalevy@panasas.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

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

Move the common code for setting up the nfs_write_data and nfs_read_data
structures into fs/nfs/read.c, fs/nfs/write.c and fs/nfs/direct.c.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

We want the default scheduling priority (priority == 0) to remain
RPC_PRIORITY_NORMAL.

Also ensure that the priority wait queue scheduling is per process id
instead of sometimes being per thread, and sometimes being per inode.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

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

By using the TASK_KILLABLE infrastructure, we can get rid of the 'intr'
mount option.  We have to use _killable everywhere instead of _interruptible
as we get rid of rpc_clnt_sigmask/sigunmask.
Signed-off-by: NLiam R. Howlett <howlett@gmail.com>
Signed-off-by: NMatthew Wilcox <willy@linux.intel.com>

NFSv3 will correctly update atime on a read() call, so there is no need to
set the NFS_INO_INVALID_ATIME flag unless the call to nfs_refresh_inode()
fails.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

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

Slab destructors were no longer supported after Christoph's
c59def9f change. They've been
BUGs for both slab and slub, and slob never supported them
either.

This rips out support for the dtor pointer from kmem_cache_create()
completely and fixes up every single callsite in the kernel (there were
about 224, not including the slab allocator definitions themselves,
or the documentation references).
Signed-off-by: NPaul Mundt <lethal@linux-sh.org>

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

Since PG_uptodate may now end up getting set during the call to
nfs_wb_page(), we can avoid putting a read request on the wire in those
situations.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Use zero_user_page() instead of the newly deprecated memclear_highpage_flush().
Signed-off-by: NNate Diller <nate.diller@gmail.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

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

Do the coalescing of read requests into block sized requests at start of
I/O as we scan through the pages instead of going through a second pass.
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>

The tk_pid field is an unsigned short.  The proper print format specifier for
that type is %5u, not %4d.

Also clean up some miscellaneous print formatting nits.
Signed-off-by: NChuck Lever <chuck.lever@oracle.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

It makes no sense to maintain 2 parallel systems for reading in pages.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Replace all uses of kmem_cache_t with struct kmem_cache.

The patch was generated using the following script:

	#!/bin/sh
	#
	# Replace one string by another in all the kernel sources.
	#

	set -e

	for file in `find * -name "*.c" -o -name "*.h"|xargs grep -l $1`; do
		quilt add $file
		sed -e "1,\$s/$1/$2/g" $file >/tmp/$$
		mv /tmp/$$ $file
		quilt refresh
	done

The script was run like this

	sh replace kmem_cache_t "struct kmem_cache"
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

SLAB_NOFS is an alias of GFP_NOFS.
Signed-off-by: NChristoph Lameter <clameter@sgi.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Clean up a lot of ad-hoc page length calculations in fs/nfs/write.c
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>