Thanks to Frank Van Maarseveen for the original problem report: "A
privileged process on an NFS client which drops privileges after using
them to change the current working directory, will experience incorrect
EACCES after an NFS server reboot. This problem can also occur after
memory pressure on the server, particularly when the client side is
quiet for some time."

This occurs because the filehandle points to a directory whose parents
are no longer in the dentry cache, and we're attempting to reconnect the
directory to its parents without adequate permissions to perform lookups
in the parent directories.

We can therefore fix the problem by acquiring the necessary capabilities
before attempting the reconnection.  We do this only in the
no_subtree_check case, since the documented behavior of the
subtree_check export option requires the server to check that the user
has lookup permissions on all parents.

The subtree_check case still has a problem, since reconnect_path()
unnecessarily requires both read and lookup permissions on all parent
directories.  However, a fix in that case would be more delicate, and
use of subtree_check is already discouraged for other reasons.
Signed-off-by: Neil Brown <neilb@suse.de>
Cc: Frank van Maarseveen <frankvm@frankvm.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

Initialize the value used for the confounder to a random value
rather than starting from zero.
Allow for confounders of length 8 or 16 (which will be needed for AES).
Signed-off-by: Kevin Coffman <kwc@citi.umich.edu>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

The gss_krb5_crypto.o object belongs in the rpcsec_gss_krb5 module.
Also, there is no need to export symbols from gss_krb5_crypto.c
Signed-off-by: Kevin Coffman <kwc@citi.umich.edu>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

cleanup:
Document token header size with a #define instead of open-coding it.

Don't needlessly increment "ptr" past the beginning of the header
which makes the values passed to functions more understandable and
eliminates the need for extra "krb5_hdr" pointer.

Clean up some intersecting  white-space issues flagged by checkpatch.pl.

This leaves the checksum length hard-coded at 8 for DES.  A later patch
cleans that up.
Signed-off-by: Kevin Coffman <kwc@citi.umich.edu>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

Rename nfsd_permission() specific MAY_* flags to NFSD_MAY_* to make it
clear, that these are not used outside nfsd, and to avoid name and
number space conflicts with the VFS.

[comment from hch: rename MAY_READ, MAY_WRITE and MAY_EXEC as well]
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

OCFS2 can return -ERESTARTSYS from write requests (and possibly
elsewhere) if there is a signal pending.

If nfsd is shutdown (by sending a signal to each thread) while there
is still an IO load from the client, each thread could handle one last
request with a signal pending.  This can result in -ERESTARTSYS
which is not understood by nfserrno() and so is reflected back to
the client as nfserr_io aka -EIO.  This is wrong.

Instead, interpret ERESTARTSYS to mean "try again later" by returning
nfserr_jukebox.  The client will resend and - if the server is
restarted - the write will (hopefully) be successful and everyone will
be happy.

 The symptom that I narrowed down to this was:
    copy a large file via NFS to an OCFS2 filesystem, and restart
    the nfs server during the copy.
    The 'cp' might get an -EIO, and the file will be corrupted -
    presumably holes in the middle where writes appeared to fail.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

We need the nfsd_mutex before accessing nfsd_serv->sv_nrthreads or we
can't even guarantee nfsd_serv will still be there.
Signed-off-by: Neil Brown <neilb@suse.de>
Acked-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

If lockd_down is called very rapidly after lockd_up returns, then
there is a slim chance that lockd() will never be called. kthread()
will return before calling the function, so we'll end up never
actually calling the cleanup functions for the thread.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

Since we no longer make any distinction between shutdown signals with
nfsd, then it becomes easier to just standardize on a particular signal
to use to bring it down (SIGINT, in this case).
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

This patch is rather large, but I couldn't figure out a way to break it
up that would remain bisectable. It does several things:

- change svc_thread_fn typedef to better match what kthread_create expects
- change svc_pool_map_set_cpumask to be more kthread friendly. Make it
  take a task arg and and get rid of the "oldmask"
- have svc_set_num_threads call kthread_create directly
- eliminate __svc_create_thread
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

The special handling for SIGHUP in knfsd is a holdover from much
earlier versions of Linux where reloading the export table was
more expensive. That facility is not really needed anymore and
to my knowledge, is seldom-used.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

Several of the nfsd filesystem interfaces allow changes to parameters
that don't have any effect on a running nfsd service. They are only ever
checked when nfsd is started. This patch fixes it so that changes to
those procfiles return -EBUSY if nfsd is already running to make it
clear that changes on the fly don't work.

The patch should also close some relatively harmless races between
changing the info in those interfaces and starting nfsd, since these
variables are being moved under the protection of the nfsd_mutex.

Finally, the nfsv4recoverydir file always returns -EINVAL if read. This
patch fixes it to return the recoverydir path as expected.
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

This removes the BKL from the RPC service creation codepath. The BKL
really isn't adequate for this job since some of this info needs
protection across sleeps.

Also, add some comments to try and clarify how the locking should work
and to make it clear that the BKL isn't necessary as long as there is
adequate locking between tasks when touching the svc_serv fields.
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Jeff Layton <jlayton@redhat.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

The cb_stat member of struct nfs4_callback is unused
since commit ff7d9756 nfsd: use static memory for callback program and stats
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

The cb_program member of struct nfs4_callback unused
since commit ff7d9756 nfsd: use static memory for callback program and stats
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

These flag bits aren't used by either the protocol or our
implementation, so I don't know why they were here.

Thanks to Johann Dahm for running across these.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>
Cc: Johann Dahm <jdahm@umich.edu>

WRITEMEM zeroes the last word in the destination buffer
for padding purposes, but this must not be done if
no bytes are to be copied, as it would result
in zeroing of the word right before the array.

The current implementation works since it's always called
with non zero nbytes or it follows an encoding of the
string (or opaque) length which, if equal to zero,
can be overwritten with zero.

Nevertheless, it seems safer to check for this case.
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

We already print each operation of the compound when debugging is turned
on; printing the result could also help with remote debugging.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

These bit operations don't need to be atomic.  They're all done under a
single big mutex anyway.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

* 'i2c-for-linus' of git://jdelvare.pck.nerim.net/jdelvare-2.6:
  i2c/max6875: Really prevent 24RF08 corruption
  i2c-amd756: Fix functionality flags
  i2c: Kill the old driver matching scheme
  i2c: Convert remaining new-style drivers to use module aliasing
  i2c: Switch pasemi to the new device/driver matching scheme
  i2c: Clean up Blackfin BF527 I2C device declarations
  i2c-nforce2: Disable the second SMBus channel on the DFI Lanparty NF4 Expert
  i2c: New co-maintainer

Add multi_defconfig, to build a kernel for all supported m68k platforms,
excluding Sun 3 (Sun 3 kernels are incompatible with all other m68k platforms)
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Update the m68k defconfigs
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

m68k: Correctly handle multi-ISA at runtime in multi-platform kernels
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The *_ISA type defines are quite generic and cause namespace conflicts
(e.g. with `AMIGAHW_DECLARE(GG2_ISA)' in <asm/amigahw.h>) for some kernel
configurations. Use ISA_TYPE_* to avoid such conflicts.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

UIO needs m68k_mmutype:

ERROR: "m68k_mmutype" [drivers/uio/uio.ko] undefined!

(noticed by Christian T. Steigies)
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Mark Q40/Q60 floppy support broken:

    arch/m68k/q40/q40ints.c: In function 'q40_irq_handler':
    arch/m68k/q40/q40ints.c:214: error: implicit declaration of function 'floppy_hardint'

Including <asm/floppy.h> doesn't help, as it causes a lot of additional error
messages (cfr. Sun 3x).
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

According to the tests in do_initcalls(), the proper error code in case no
device is found is -ENODEV, not -ENXIO or -EIO.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Some input drivers do not check whether they're actually running on the
correct platform, causing multi-platform kernels to crash if they are not.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Some network drivers do not check whether they're actually running on the
correct platform, causing multi-platform kernels to crash if they are not.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The Apollo frame buffer device driver (dnfb) doesn't check whether it's
actually running on Apollo hardware, causing a crash if it isn't.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The Macintosh IDE driver (macide) doesn't check whether it's actually running
on Mac hardware, causing a crash if it isn't.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

When running a HP300-enabled kernel on non-HP300 hardware, a test in the early
startup code jumps to the wrong label, causing a double bus fault.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Use `__builtin_trap()' instead of `asm volatile("illegal")' in the m68k BUG()
macros (as suggested by Andrew Pinski), to kill warnings in code that assumes
BUG() does not return.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

m68k vme_scc:
  - make scc_ports[] static
  - kill unused global scc_initialized
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The Hisoft Whippet PCMCIA serial driver has been removed a long time ago, but
it's Kconfig symbol still existed.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Correct FB_HP300 dependencies:
  - FB_HP300 doesn't depend only on HP300, but also on DIO (which depends on
    HP300)
  - FB_HP300 does not need FB_CFB_FILLRECT
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

CONFIG_FB_DAFB is a leftover from pre-Kconfig
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Convert access_ok() from a macro to an inline function, so the compiler no
longer complains about unused variables:

    fs/read_write.c: In function 'rw_copy_check_uvector':
    fs/read_write.c:556: warning: unused variable 'buf'
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

i2c-core takes care of the possible corruption of 24RF08 chips for
quite some times, so device devices no longer need to do it. And they
really should not, as applying the prevention twice voids it.

I thought that I had fixed all drivers long ago but apparently I had
missed that one.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Cc: Ben Gardner <bgardner@wabtec.com>