If a server for some reason keeps sending NFS4ERR_DELAY errors, we can end
up looping forever inside nfs4_proc_create_session, and so the usual
mechanisms for detecting if the nfs_client is dead don't work.

Fix this by ensuring that we loop inside the nfs4_state_manager thread
instead.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

I only want to try other secflavors during an initial mount if
NFS4ERR_WRONGSEC is returned.  nfs4_handle_exception() could
potentially map other errors to EPERM, so we should handle this
error specially for correctness.
Signed-off-by: NBryan Schumaker <bjschuma@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

If we fail to contact the gss upcall program, then no message will
be sent to the server.  The client still updated the sequence number,
however, and this lead to NFS4ERR_SEQ_MISMATCH for the next several
RPC calls.
Signed-off-by: NBryan Schumaker <bjschuma@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

Currently, the state manager may continue to try recovering state forever
even after the last filesystem to reference that nfs_client has umounted.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org

Since kernel 2.6.35, the SUNRPC Kerberos support has had an implicit
dependency on a number of additional crypto modules. The following
patch makes that dependency explicit.
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

While decoding a secinfo reply, I store the list of supported sec
flavors on a page accessible through res->flavors.  Before reading
each new flavor, I do some math to determine if there is enough
space left on this page, and I break out of my read look if there
isn't.  In order to perform this check correctly, I need to use the
address of res->flavors, rather than the address of res.

When this loop was broken early I lied to the caller and told them
that the entire list had been decoded.  This could lead to problems
if the caller tries to use any the garbage data claiming to be a
valid sec flavor.  I fixed this by using res->flavors->num_flavors
as a counter, incrementing it every time a sec flavor is
successfully decoded.
Signed-off-by: NBryan Schumaker <bjschuma@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

We were always attempting sec flavor negotiation, even if the user
told us a specific sec flavor to use.  If that sec flavor fails,
we should return an error rather than continuing with sec flavor
negotiation.
Signed-off-by: NBryan Schumaker <bjschuma@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

nfs4_lookup_root() is already configured to use either RPC_AUTH_UNIX
or a user specified flavor (through -o sec=<whatever>).  We should
use this flavor first, and only attempt negotiation if it fails
with -EPERM.
Signed-off-by: NBryan Schumaker <bjschuma@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

NFS_MAX_SECFLAVORS should already take into account RPC_AUTH_UNIX
and RPC_AUTH_NULL, so we don't need to set aside extra slots
for them.
Signed-off-by: NBryan Schumaker <bjschuma@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

There can be an infinite loop if gss_create_upcall() is called without
the userspace program running.  To prevent this, we return -EACCES if
we notice that pipe_version hasn't changed (indicating that the pipe
has not been opened).
Signed-off-by: NBryan Schumaker <bjschuma@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

mark_inode_dirty_sync() grabs the same inode lock!

race conditions between holding the lock in pnfs_set_layoutcommit() and in
mark_inode_dirty_sync() can result in a second call to pnfs_layoutcommit_inode(), but
this will be a noop as NFS_INO_LAYOUTCOMMIT won't be set in the second call
Signed-off-by: NWeston Andros Adamson <dros@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

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

The inode was used in an earlier version of the code, but it isn't
used anymore.
Signed-off-by: NBryan Schumaker <bjschuma@netapp.com>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

We only need to call nfs_mark_request_dirty() once in nfs_writepage_setup().
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

In fs/nfs/super.c::nfs_fs_mount() we test for a NULL 'data':

...
 		if (data == NULL || mntfh == NULL)
 			goto out_free_fh;
...

and then further down in the function we test 'data' again:

...
 			nfs_fscache_get_super_cookie(
 				s, data ? data->fscache_uniq : NULL, NULL);
...

this second check is just dead code since there is no way 'data' could
possibly be NULL here.
We also rely on a non-NULL 'data' in more than one location between these
two tests, further proving the point that the second test is bogus.

This patch removes the dead code.
Signed-off-by: NJesper Juhl <jj@chaosbits.net>
Signed-off-by: NTrond Myklebust <Trond.Myklebust@netapp.com>

* git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6:
  cifs: don't allow mmap'ed pages to be dirtied while under writeback (try #3)
  [CIFS] Warn on requesting default security (ntlm) on mount
  [CIFS] cifs: clarify the meaning of tcpStatus == CifsGood
  cifs: wrap received signature check in srv_mutex
  cifs: clean up various nits in unicode routines (try #2)
  cifs: clean up length checks in check2ndT2
  cifs: set ra_pages in backing_dev_info
  cifs: fix broken BCC check in is_valid_oplock_break
  cifs: always do is_path_accessible check in cifs_mount
  various endian fixes to cifs
  Elminate sparse __CHECK_ENDIAN__ warnings on port conversion
  Max share size is too small
  Allow user names longer than 32 bytes
  cifs: replace /proc/fs/cifs/Experimental with a module parm
  cifs: check for private_data before trying to put it

Merge branch 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mjg59/platform-drivers-x86

* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mjg59/platform-drivers-x86:
  thinkpad-acpi fails to load with newer Thinkpad X201s BIOS
  acer-wmi: Fix capitalisation of GUID in module alias
  sony-laptop: keyboard backlight fixes
  sony-laptop: only show the handles sysfs file in debug mode
  samsung-laptop: set backlight type
  staging: samsung-laptop has moved to platform/x86
  samsung-laptop: Samsung R410P backlight driver
  samsung-laptop: add support for N230 model
  platform-drivers: x86: pmic: Restore the dropped buslock/unlock
  sony-laptop: fix early NULL pointer dereference
  msi-laptop: fix config-dependent build error
  eeepc-wmi: add keys found on EeePC 1215T
  asus-wmi: swap input name and phys
  asus-laptop: remove removed features from feature-removal-schedule.txt

Gaah.  When commit be85bcca reverted the export of file system uuid
via /proc/<pid>/mountinfo, it also unintentionally removed the s_uuid
field in struct super_block.

I didn't mean to do that, since filesystems have been taught to fill it
in (and we want to keep it for future re-introduction in the mountinfo
file).

Stupid of me. This adds it back in.
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sameo/mfd-2.6:
  mfd: Fetch cell pointer from platform_device->mfd_cell

nfs_scan_commit() is called with the inode->i_lock held, but it then
calls __mark_inode_dirty() while still holding the lock. This causes
a deadlock.

Push the inode->i_lock into nfs_scan_commit() so it can protect only
the parts of the code it needs to and can be dropped before the call
to __mark_inode_dirty() to avoid the deadlock.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Tested-by: NWill Simoneau <simoneau@ele.uri.edu>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Commit 53a7706d ("mlock: do not hold mmap_sem for extended periods
of time") changed mlock() to care about the exact number of pages that
__get_user_pages() had brought it.  Before, it would only care about
errors.

And that doesn't work, because we also handled one page specially in
__mlock_vma_pages_range(), namely the stack guard page.  So when that
case was handled, the number of pages that the function returned was off
by one.  In particular, it could be zero, and then the caller would end
up not making any progress at all.

Rather than try to fix up that off-by-one error for the mlock case
specially, this just moves the logic to handle the stack guard page
into__get_user_pages() itself, thus making all the counts come out
right automatically.
Reported-by: NRobert Święcki <robert@swiecki.net>
Cc: Hugh Dickins <hughd@google.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: stable@kernel.org
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This reverts commit 93f1c20b.

It turns out that libmount misparses it because it adds a '-' character
in the uuid string, which libmount then incorrectly confuses with the
separator string (" - ") at the end of all the optional arguments.

Upstream libmount (in the util-linux tree) has been fixed, but until
that fix actually percolates up to users, we'd better not expose this
change in the kernel.

Let's revisit this later (possibly by exposing the UUID without any '-'
characters in it, avoiding the user-space bug).
Reported-by: NDave Jones <davej@redhat.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Karel Zak <kzak@redhat.com>
Cc: Ram Pai <linuxram@us.ibm.com>
Cc: Miklos Szeredi <mszeredi@suse.cz>
Cc: Eric Sandeen <sandeen@redhat.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The new BIOS has a slightly different EC version string.

From a1541710300b083a1a9acff2890d721d15ede62b Mon Sep 17 00:00:00 2001
From: Keith Packard <keithp@keithp.com>
Date: Sun, 13 Mar 2011 23:46:22 -0700
Subject: [PATCH] thinkpad-acpi: Some BIOS versions don't end in WW, remove check

My X201s BIOS version string is 6QET46V1 (1.16 ). The
EC version string is 6QHT28WW-1.09. The driver was requiring that both
of these have 'WW' in positions 6 and 7. I don't know what the
significance of having 'V1' there instead is, but removing the test
makes the driver load on my machine.
Signed-off-by: NKeith Packard <keithp@keithp.com>
Signed-off-by: NMatthew Garrett <mjg@redhat.com>

wmi:6AF4F258-B401-42Fd-BE91-3D4AC2D7C0D3 needs to be
wmi:6AF4F258-B401-42FD-BE91-3D4AC2D7C0D3 in module alias for acer-wmi is
automatically loaded.

Cc: Pali Rohár <pali.rohar@gmail.com>
Cc: Carlos Corbacho <carlos@strangeworlds.co.uk>
Cc: Matthew Garrett <mjg@redhat.com>
Signed-off-by: NLee, Chun-Yi <jlee@novell.com>
Signed-off-by: NMatthew Garrett <mjg@redhat.com>

Restore the original state on module removal, set the latest values on
resume.
When setting the keyboard backlight mode try to turn on/off backlight
immediately.

[malattia@linux.it: patch taken from a largely modified sony-laptop.c,
ported and slightly modified to use defines already available.]
Signed-off-by: NMattia Dongili <malattia@linux.it>
Signed-off-by: NMatthew Garrett <mjg@redhat.com>

It makes no sense to expose this type of information to userspace unless
the driver was explicitly loaded with the debug option.
Signed-off-by: NMattia Dongili <malattia@linux.it>
Signed-off-by: NMatthew Garrett <mjg@redhat.com>

Cherry-picked from drivers/staging/samsung-laptop/samsung-laptop.c
Signed-off-by: NMichal Marek <mmarek@suse.cz>
Signed-off-by: NMatthew Garrett <mjg@redhat.com>

Signed-off-by: NMichal Marek <mmarek@suse.cz>
Signed-off-by: NMatthew Garrett <mjg@redhat.com>

Here's a trivial patch which adds support to the backlight device found
in Samsung R410 Plus laptops.
Signed-off-by: NAlberto Mardegan <mardy@users.sourceforge.net>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
[mmarek: cherry-picked from staging commit d542f180]
Signed-off-by: NMichal Marek <mmarek@suse.cz>
Signed-off-by: NMatthew Garrett <mjg@redhat.com>

Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
[mmarek: cherry-picked from staging commit 0789b003]
Signed-off-by: NMichal Marek <mmarek@suse.cz>
Signed-off-by: NMatthew Garrett <mjg@redhat.com>

This is more or less the same patch as before, but with some merge
conflicts fixed up.

If a process has a dirty page mapped into its page tables, then it has
the ability to change it while the client is trying to write the data
out to the server. If that happens after the signature has been
calculated then that signature will then be wrong, and the server will
likely reset the TCP connection.

This patch adds a page_mkwrite handler for CIFS that simply takes the
page lock. Because the page lock is held over the life of writepage and
writepages, this prevents the page from becoming writeable until
the write call has completed.

With this, we can also remove the "sign_zero_copy" module option and
always inline the pages when writing.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

In order for MFD drivers to fetch their cell pointer but also their
platform data one, an mfd cell pointer is added to the platform_device
structure.
That allows all MFD sub devices drivers to be MFD agnostic, unless
they really need to access their MFD cell data. Most of them don't,
especially the ones for IPs used by both MFD and non MFD SoCs.

Cc: Grant Likely <grant.likely@secretlab.ca>
Acked-by: NGreg KH <gregkh@suse.de>
Signed-off-by: NSamuel Ortiz <sameo@linux.intel.com>

* 'stable/bug-fixes-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen: Allow PV-OPS kernel to detect whether XSAVE is supported
  xen: just completely disable XSAVE
  xen/debug: Don't be so verbose with WARN on 1-1 mapping errors.
  xen: events: fix error checks in bind_*_to_irqhandler()

Warn once if default security (ntlm) requested. We will
update the default to the stronger security mechanism
(ntlmv2) in 2.6.41.  Kerberos is also stronger than
ntlm, but more servers support ntlmv2 and ntlmv2
does not require an upcall, so ntlmv2 is a better
default.
Reviewed-by: NJeff Layton <jlayton@redhat.com>
CC: Suresh Jayaraman <sjayaraman@suse.de>
Reviewed-by: NShirish Pargaonkar <shirishp@us.ibm.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

When the TCP_Server_Info is first allocated and connected, tcpStatus ==
CifsGood means that the NEGOTIATE_PROTOCOL request has completed and the
socket is ready for other calls. cifs_reconnect however sets tcpStatus
to CifsGood as soon as the socket is reconnected and the optional
RFC1001 session setup is done. We have no clear way to tell the
difference between these two states, and we need to know this in order
to know whether we can send an echo or not.

Resolve this by adding a new statusEnum value -- CifsNeedNegotiate. When
the socket has been connected but has not yet had a NEGOTIATE_PROTOCOL
request done, set it to this value. Once the NEGOTIATE is done,
cifs_negotiate_protocol will set tcpStatus to CifsGood.

This also fixes and cleans the logic in cifs_reconnect and
cifs_reconnect_tcon. The old code checked for specific states when what
it really wants to know is whether the state has actually changed from
CifsNeedReconnect.
Reported-and-Tested-by: NJG <jg@cms.ac>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

While testing my patchset to fix asynchronous writes, I hit a bunch
of signature problems when testing with signing on. The problem seems
to be that signature checks on receive can be running at the same
time as a process that is sending, or even that multiple receives can
be checking signatures at the same time, clobbering the same data
structures.

While we're at it, clean up the comments over cifs_calculate_signature
and add a note that the srv_mutex should be held when calling this
function.

This patch seems to fix the problems for me, but I'm not clear on
whether it's the best approach. If it is, then this should probably
go to stable too.

Cc: stable@kernel.org
Cc: Shirish Pargaonkar <shirishpargaonkar@gmail.com>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Minor revision to the original patch. Don't abuse the __le16 variable
on the stack by casting it to wchar_t and handing it off to char2uni.
Declare an actual wchar_t on the stack instead. This fixes a valid
sparse warning.

Fix the spelling of UNI_ASTERISK. Eliminate the unneeded len_remaining
variable in cifsConvertToUCS.

Also, as David Howells points out. We were better off making
cifsConvertToUCS *not* use put_unaligned_le16 since it means that we
can't optimize the mapped characters at compile time. Switch them
instead to use cpu_to_le16, and simply use put_unaligned to set them
in the string.
Reported-and-acked-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Thus spake David Howells:

The code that follows this:

  	remaining = total_data_size - data_in_this_rsp;
	if (remaining == 0)
		return 0;
	else if (remaining < 0) {

generates better code if you drop the 'remaining' variable and compare
the values directly.

Clean it up per his recommendation...
Reported-and-acked-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

Commit 522440ed made cifs set backing_dev_info on the mapping attached
to new inodes. This change caused a fairly significant read performance
regression, as cifs started doing page-sized reads exclusively.

By virtue of the fact that they're allocated as part of cifs_sb_info by
kzalloc, the ra_pages on cifs BDIs get set to 0, which prevents any
readahead. This forces the normal read codepaths to use readpage instead
of readpages causing a four-fold increase in the number of read calls
with the default rsize.

Fix it by setting ra_pages in the BDI to the same value as that in the
default_backing_dev_info.

Fixes https://bugzilla.kernel.org/show_bug.cgi?id=31662

Cc: stable@kernel.org
Reported-and-Tested-by: NTill <till2.schaefer@uni-dortmund.de>
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>

The BCC is still __le16 at this point, and in any case we need to
use the get_bcc_le macro to make sure we don't hit alignment
problems.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Signed-off-by: NSteve French <sfrench@us.ibm.com>