NFSd assumes that largest number of pages that will be needed for a
request+response is 2+N where N pages is the size of the largest permitted
read/write request.  The '2' are 1 for the non-data part of the request, and 1
for the non-data part of the reply.

However, when a read request is not page-aligned, and we choose to use
->sendfile to send it directly from the page cache, we may need N+1 pages to
hold the whole reply.  This can overflow and array and cause an Oops.

This patch increases size of the array for holding pages by one and makes sure
that entry is NULL when it is not in use.
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Due to silly typos, if the nfs versions are explicitly set, no NFSACL versions
get enabled.

Also improve an error message that would have made this bug a little easier to
find.
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The nfsservctl system call isn't used but recent nfs-utils releases for
exporting filesystems, and consequently the code that is uses - exp_export -
has suffered some bitrot.

Particular:
  - some newly added fields in 'struct svc_export' are being initialised
    properly.
  - the return value is now always -ENOMEM ...

This patch fixes both these problems.
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Kill another big "if" clause.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

I'm not too fond of these big if conditions.  Replace them by checks of a flag
in the operation descriptor.  To my eye this makes the code a bit more
self-documenting, and makes the complicated part of the code (proc_compound) a
little more compact.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Define an op descriptor struct, use it to simplify nfsd4_proc_compound().
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Make wrappers for verify and nverify, for consistency with other ops.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

The inlining contributes to bloating the stack of nfsd4_compound, and I want
to change the compound op functions to function pointers anyway.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Tuck away the replay_owner in the cstate while we're at it.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

OK, this is embarassing--I've even looked back at the history, and cannot for
the life of me figure out why I added this check.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Pass the saved and current filehandles together into all the nfsd4 compound
operations.

I want a unified interface to these operations so we can just call them by
pointer and throw out the huge switch statement.

Also I'll eventually want a structure like this--that holds the state used
during compound processing--for deferral.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

To avoid tying up server threads when nfsd makes an upcall (to mountd, to get
export options, to idmapd, for nfsv4 name<->id mapping, etc.), we temporarily
"drop" the request and save enough information so that we can revisit it
later.

Certain failures during the deferral process can cause us to really drop the
request and never revisit it.

This is often less than ideal, and is unacceptable in the NFSv4 case--rfc 3530
forbids the server from dropping a request without also closing the
connection.

As a first step, we modify the deferral code to return -ETIMEDOUT (which is
translated to nfserr_jukebox in the v3 and v4 cases, and remains a drop in the
v2 case).
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch on its own causes no change in behavior, since nfsd_cross_mnt()
only returns -EAGAIN; but in the future I'd like it to also be able to return
-ETIMEDOUT, so we may as well handle any possible error here.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Note there's no need for special handling of -EAGAIN here; nfserrno() does
what we want already.  So this is a pure cleanup with no change in
functionality.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Since exp_parent can fail by returning an error (-EAGAIN) in addition to by
returning NULL, we should check for that case in exp_rootfh.

(TODO: we should check that userland handles these errors too.)
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

A comment here incorrectly states that "slack_space" is measured in words, not
bytes.  Remove the comment, and adjust a variable name and a few comments to
clarify the situation.

This is pure cleanup; there should be no change in functionality.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This dprintk is printing the wrong error now, but it's probably an unnecessary
dprintk anyway; just remove it.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Annotated, all places switched to keeping status net-endian.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Acked-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Replace kmalloc+memset with kcalloc and simplify
Signed-off-by: NYan Burman <burman.yan@gmail.com>
Cc: Neil Brown <neilb@cse.unsw.edu.au>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

NFS3: Calculate 'w' a bit later in nfs3svc_encode_getaclres()
      This is a small performance optimization since we can return before
      needing 'w'. It also saves a few bytes of .text :
      Before:
           text    data     bss     dec     hex filename
           1632     140       0    1772     6ec fs/nfsd/nfs3acl.o
      After:
           text    data     bss     dec     hex filename
           1624     140       0    1764     6e4 fs/nfsd/nfs3acl.o
Signed-off-by: NJesper Juhl <jesper.juhl@gmail.com>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

NFS2: Calculate 'w' a bit later in nfsaclsvc_encode_getaclres()
      This is a small performance optimization since we can return before
      needing 'w'. It also saves a few bytes of .text :
      Before:
           text    data     bss     dec     hex filename
           2406     212       0    2618     a3a fs/nfsd/nfs2acl.o
      After:
           text    data     bss     dec     hex filename
           2400     212       0    2612     a34 fs/nfsd/nfs2acl.o
Signed-off-by: NJesper Juhl <jesper.juhl@gmail.com>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

> =============================================
> [ INFO: possible recursive locking detected ]
> 2.6.18-1.2724.lockdepPAE #1
> ---------------------------------------------
> nfsd/6884 is trying to acquire lock:
>  (&inode->i_mutex){--..}, at: [<c04811e5>] vfs_rmdir+0x73/0xf4
>
> but task is already holding lock:
>  (&inode->i_mutex){--..}, at: [<f8dfa621>]
> nfsd4_clear_clid_dir+0x1f/0x3d [nfsd]
>
> other info that might help us debug this:
> 3 locks held by nfsd/6884:
>  #0:  (hash_sem){----}, at: [<f8de05eb>] nfsd+0x181/0x2ea [nfsd]
>  #1:  (client_mutex){--..}, at: [<f8df6d19>]
> nfsd4_setclientid_confirm+0x3b/0x2cf [nfsd]
>  #2:  (&inode->i_mutex){--..}, at: [<f8dfa621>]
> nfsd4_clear_clid_dir+0x1f/0x3d [nfsd]
>
> stack backtrace:
>  [<c040524d>] dump_trace+0x69/0x1af
>  [<c04053ab>] show_trace_log_lvl+0x18/0x2c
>  [<c040595f>] show_trace+0xf/0x11
>  [<c0405a53>] dump_stack+0x15/0x17
>  [<c043ca7a>] __lock_acquire+0x110/0x9b6
>  [<c043d91e>] lock_acquire+0x5c/0x7a
>  [<c061a41b>] __mutex_lock_slowpath+0xde/0x234
>  [<c04811e5>] vfs_rmdir+0x73/0xf4
>  [<f8dfa62b>] nfsd4_clear_clid_dir+0x29/0x3d [nfsd]
>  [<f8dfa733>] nfsd4_remove_clid_dir+0xb8/0xf8 [nfsd]
>  [<f8df6e90>] nfsd4_setclientid_confirm+0x1b2/0x2cf [nfsd]
>  [<f8def19a>] nfsd4_proc_compound+0x137a/0x166c [nfsd]
>  [<f8de00d5>] nfsd_dispatch+0xc5/0x180 [nfsd]
>  [<f8d09d83>] svc_process+0x3bd/0x631 [sunrpc]
>  [<f8de0604>] nfsd+0x19a/0x2ea [nfsd]
>  [<c0404e27>] kernel_thread_helper+0x7/0x10
> DWARF2 unwinder stuck at kernel_thread_helper+0x7/0x10
> Leftover inexact backtrace:
>  =======================

Some nesting annotation to the nfsd4 recovery code.
The vfs operations called will take dentry->d_inode->i_mutex.
Signed-off-by: NPeter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Neil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Change all the uses of f_{dentry,vfsmnt} to f_path.{dentry,mnt} in the nfs
server code.
Signed-off-by: NJosef "Jeff" Sipek <jsipek@cs.sunysb.edu>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

This patch removes the unused NFSD_OPTIMIZE_SPACE.

Additionally, it does differently what NFSD_OPTIMIZE_SPACE was supposed to do:

Nowadays, gcc knows best when to inline code, and CONFIG_CC_OPTIMIZE_FOR_SIZE
even tells gcc globally whether to optimize for size or for speed.  Therefore,
this patch also removes all inline's from these files.
Signed-off-by: NAdrian Bunk <bunk@stusta.de>
Acked-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

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>

Fix up for make allyesconfig.
Signed-Off-By: NDavid Howells <dhowells@redhat.com>

Commit 6264d69d modified the nfsd_create()
error handling in such a way that nfsd_create will usually return
nfserr_perm even when succesful, if the export has the async export option.

This introduced a regression that could cause mkdir() to always return a
permissions error, even though the directory in question was actually
succesfully created.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Acked-by: NNeilBrown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

In the case where an open creates the file, we shouldn't be rechecking
permissions to open the file; the open succeeds regardless of what the new
file's mode bits say.

This patch fixes the problem, but only by introducing yet another parameter
to nfsd_create_v3.  This is ugly.  This will be fixed by later patches.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Acked-by: NNeil Brown <neilb@suse.de>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Minor rearrangement, cleanup of do_open_lookup().  No change in behavior.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Acked-by: NNeil Brown <neilb@suse.de>
Cc: Jeff Garzik <jeff@garzik.org>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

When I was performing some operations on NFS, I got below error on server
side.

  =============================================
  [ INFO: possible recursive locking detected ]
  2.6.19-prep #1
  ---------------------------------------------
  nfsd4/3525 is trying to acquire lock:
   (&inode->i_mutex){--..}, at: [<c0611e5a>] mutex_lock+0x21/0x24

  but task is already holding lock:
   (&inode->i_mutex){--..}, at: [<c0611e5a>] mutex_lock+0x21/0x24

  other info that might help us debug this:
  2 locks held by nfsd4/3525:
   #0:  (client_mutex){--..}, at: [<c0611e5a>] mutex_lock+0x21/0x24
   #1:  (&inode->i_mutex){--..}, at: [<c0611e5a>] mutex_lock+0x21/0x24

  stack backtrace:
   [<c04051ed>] show_trace_log_lvl+0x58/0x16a
   [<c04057fa>] show_trace+0xd/0x10
   [<c0405913>] dump_stack+0x19/0x1b
   [<c043b6f1>] __lock_acquire+0x778/0x99c
   [<c043be86>] lock_acquire+0x4b/0x6d
   [<c0611ceb>] __mutex_lock_slowpath+0xbc/0x20a
   [<c0611e5a>] mutex_lock+0x21/0x24
   [<c047fd7e>] vfs_rmdir+0x76/0xf8
   [<f94b7ce9>] nfsd4_clear_clid_dir+0x2c/0x41 [nfsd]
   [<f94b7de9>] nfsd4_remove_clid_dir+0xb1/0xe8 [nfsd]
   [<f94b307b>] laundromat_main+0x9b/0x1c3 [nfsd]
   [<c04333d6>] run_workqueue+0x7a/0xbb
   [<c0433d0b>] worker_thread+0xd2/0x107
   [<c0436285>] kthread+0xc3/0xf2
   [<c0402005>] kernel_thread_helper+0x5/0xb
  ===================================================================

Cause for this problem was,2 successive mutex_lock calls on 2 diffrent inodes ,as shown below

	static int
	nfsd4_clear_clid_dir(struct dentry *dir, struct dentry *dentry)
	{
	        int status;

	        /* For now this directory should already be empty, but we empty it of
        	 * any regular files anyway, just in case the directory was created by
	         * a kernel from the future.... */
        	nfsd4_list_rec_dir(dentry, nfsd4_remove_clid_file);
	        mutex_lock(&dir->d_inode->i_mutex);
	        status = vfs_rmdir(dir->d_inode, dentry);
	...

	int vfs_rmdir(struct inode *dir, struct dentry *dentry)
	{
	        int error = may_delete(dir, dentry, 1);

	        if (error)
	                return error;

	        if (!dir->i_op || !dir->i_op->rmdir)
        	        return -EPERM;

	        DQUOT_INIT(dir);

	        mutex_lock(&dentry->d_inode->i_mutex);
	...

So I have developed the patch to overcome this problem.
Signed-off-by: NSrinivasa DS <srinivasa@in.ibm.com>
Cc: Neil Brown <neilb@suse.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

We are using NFS_REPLAY_ME as a special error value that is never leaked to
clients.  That works fine; the only problem is mixing host- and network-
endian values in the same objects.  Network-endian equivalent would work just
as fine; switch to it.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Acked-by: NTrond Myklebust <trond.myklebust@fys.uio.no>
Acked-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Acked-by: NTrond Myklebust <trond.myklebust@fys.uio.no>
Acked-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Acked-by: NTrond Myklebust <trond.myklebust@fys.uio.no>
Acked-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

don't use the same variable to store NFS and host error values
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Acked-by: NTrond Myklebust <trond.myklebust@fys.uio.no>
Acked-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Acked-by: NTrond Myklebust <trond.myklebust@fys.uio.no>
Acked-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Acked-by: NTrond Myklebust <trond.myklebust@fys.uio.no>
Acked-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

don't use the same variable to store NFS and host error values
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Acked-by: NTrond Myklebust <trond.myklebust@fys.uio.no>
Acked-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Acked-by: NTrond Myklebust <trond.myklebust@fys.uio.no>
Acked-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Acked-by: NTrond Myklebust <trond.myklebust@fys.uio.no>
Acked-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>

Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Acked-by: NTrond Myklebust <trond.myklebust@fys.uio.no>
Acked-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@osdl.org>
Signed-off-by: NLinus Torvalds <torvalds@osdl.org>