Tighten error paths used by various i2c adapters (mostly x86) so
they return real fault/errno codes instead of a "-1" (which is
most often interpreted as "-EPERM").  Build tested, with eyeball
review.

One minor initial goal is to have adapters consistently return
the code "-ENXIO" when addressing a device doesn't get an ACK
response, at least in the probe paths where they are already
good at stifling related logspam.
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

Defend the i2c refcount calls against NULL pointers, as is important
(and conventional) for such calls.  Note that none of the current
callers of i2c_use_client() use its return value.

[JD: I hate this but apparently all the other subsystems do it so...]
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

Provide kerneldoc for most of the I2C and SMBus I/O calls.  Add a
comment summarizing some fault reporting issues which affect the
ability to provide clean fault reports through I2C master transfer
calls.  (Making it hard to precisely specify their return values...)
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

That function is actually named i2c_smbus_xfer.
Signed-off-by: NJean Delvare <khali@linux-fr.org>

Function i2c_smbus_write_quick has no users left, so we can delete it.

Also update the list of these helper functions which are gone but
could be added back if needed.
Signed-off-by: NJean Delvare <khali@linux-fr.org>

The list of I2C/SMBus bus drivers is growing and it is sometimes
difficult for the users to figure out what drivers they should enable.
By grouping the drivers by type, I hope to make the selection easier.
Signed-off-by: NJean Delvare <khali@linux-fr.org>

More updates to the I2C stack's fault reporting:  make the core stop
returning "-1" (usually "-EPERM") for all faults.  Instead, pass lower
level fault code up the stack, or return some appropriate errno.

This patch happens to touch almost exclusively SMBus calls.
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

i2c-core doesn't use seq files, so doesn't need to include
<linux/seq_file.h>.
Signed-off-by: NJean Delvare <khali@linux-fr.org>

Create Documentation/i2c/fault-codes to help standardize
fault/error code usage in the I2C stack.  It turns out that
returning -1 (-EPERM) for everything was not at all helpful.
Signed-off-by: NDavid Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

Since only a few Blackfins lack TWI, just list them in a depends
statement.
Signed-off-by: NMike Frysinger <vapier.adi@gmail.com>
Signed-off-by: NBryan Wu <cooloney@kernel.org>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

This patch contains the scheduled removal of i2c-i810, i2c-prosavage
and i2c-savage4.
Signed-off-by: NAdrian Bunk <bunk@kernel.org>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

Just like the Tyan S4882, the S4985 uses a multiplexer to give access
to all 16 memory module SPD EEPROMs. This specific i2c-nforce2-s4985
driver adds support for this. It is heavily based on the older
i2c-amd756-s4882 driver.

As more mainboards will use multiplexer chips, we will have to find a
way to support them without having to write a new specfic driver for
each. The recent changes to the i2c subsystem should help us, and the
new gpio subsystem might help, too.
Signed-off-by: NJean Delvare <khali@linux-fr.org>

If an interrupt happens before an I2c master read/write,
complete is called on uninitialized structure.
Signed-off-by: NTroy Kisky <troy.kisky@boundarydevices.com>
Signed-off-by: NKevin Hilman <khilman@mvista.com>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

If wait_for_completion_interruptible_timeout exits due
to a signal, the i2c bus was locking up.
Signed-off-by: NTroy Kisky <troy.kisky@boundarydevices.com>
Signed-off-by: NKevin Hilman <khilman@mvista.com>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

Interrupts are enabled at the point where the DAVINCI_I2C_IVR_REG is read,
so unless an interrupt happened just at that moment, no interrupt would be
pending. Even though documentation implies you should do this, I see no
reason. If slave support is added, this read would cause a hard to
reproduce bug.
Signed-off-by: NTroy Kisky <troy.kisky@boundarydevices.com>
Signed-off-by: NKevin Hilman <khilman@mvista.com>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

Previously the dev_dbg only printed if no error.
Printing also on an error is more useful
Signed-off-by: NTroy Kisky <troy.kisky@boundarydevices.com>
Signed-off-by: NKevin Hilman <khilman@mvista.com>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

Ensure psc value gives a clock between 7-12 MHz
Signed-off-by: NTroy Kisky <troy.kisky@boundarydevices.com>
Signed-off-by: NKevin Hilman <khilman@mvista.com>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

Use class_for_each_device for iteration.
Signed-off-by: NDave Young <hidave.darkstar@gmail.com>
Signed-off-by: NJean Delvare <khali@linux-fr.org>

 # cat devices.list
 c 1:3 r
 # echo 'c 1:3 w' > sub/devices.allow
 # cat sub/devices.list
 c 1:3 w

As illustrated, the parent group has no write permission to /dev/null, so
it's child should not be allowed to add this write permission.
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
Acked-by: NSerge Hallyn <serue@us.ibm.com>
Cc: Serge Hallyn <serue@us.ibm.com>
Cc: Paul Menage <menage@google.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

 # echo "b $((0x7fffffff)):$((0x80000000)) rwm" > devices.allow
 # cat devices.list
 b 214748364:-21474836 rwm

though a major/minor number of 0x800000000 is meaningless, we
should not cast it to a negative value.
Signed-off-by: NLi Zefan <lizf@cn.fujitsu.com>
Acked-by: NSerge Hallyn <serue@us.ibm.com>
Cc: Serge Hallyn <serue@us.ibm.com>
Cc: Paul Menage <menage@google.com>
Cc: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Signed-off-by: NJiri Pirko <jpirko@redhat.com>
Cc: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Merge branch 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'sched-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  cpusets, hotplug, scheduler: fix scheduler domain breakage

Commit f18f982a ("sched: CPU hotplug events must not destroy scheduler
domains created by the cpusets") introduced a hotplug-related problem as
described below:

Upon CPU_DOWN_PREPARE,

  update_sched_domains() -> detach_destroy_domains(&cpu_online_map)

does the following:

/*
 * Force a reinitialization of the sched domains hierarchy. The domains
 * and groups cannot be updated in place without racing with the balancing
 * code, so we temporarily attach all running cpus to the NULL domain
 * which will prevent rebalancing while the sched domains are recalculated.
 */

The sched-domains should be rebuilt when a CPU_DOWN ops. has been
completed, effectively either upon CPU_DEAD{_FROZEN} (upon success) or
CPU_DOWN_FAILED{_FROZEN} (upon failure -- restore the things to their
initial state). That's what update_sched_domains() also does but only
for !CPUSETS case.

With f18f982a, sched-domains' reinitialization is delegated to
CPUSETS code:

cpuset_handle_cpuhp() -> common_cpu_mem_hotplug_unplug() ->
rebuild_sched_domains()

Being called for CPU_UP_PREPARE and if its callback is called after
update_sched_domains()), it just negates all the work done by
update_sched_domains() -- i.e. a soon-to-be-offline cpu is included in
the sched-domains and that makes it visible for the load-balancer
while the CPU_DOWN ops. is in progress.

__migrate_live_tasks() moves the tasks off a 'dead' cpu (it's already
"offline" when this function is called).

try_to_wake_up() is called for one of these tasks from another CPU ->
the load-balancer (wake_idle()) picks up a "dead" CPU and places the
task on it. Then e.g. BUG_ON(rq->nr_running) detects this a bit later
-> oops.
Signed-off-by: NDmitry Adamushko <dmitry.adamushko@gmail.com>
Tested-by: NVegard Nossum <vegard.nossum@gmail.com>
Cc: Paul Menage <menage@google.com>
Cc: Max Krasnyansky <maxk@qualcomm.com>
Cc: Paul Jackson <pj@sgi.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: miaox@cn.fujitsu.com
Cc: rostedt@goodmis.org
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86: fix ldt limit for 64 bit

* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-rc-fixes-2.6:
  [SCSI] bsg: fix oops on remove
  [SCSI] fusion: default MSI to disabled for SPI and FC controllers
  [SCSI] ipr: Fix HDIO_GET_IDENTITY oops for SATA devices
  [SCSI] mptspi: fix oops in mptspi_dv_renegotiate_work()
  [SCSI] erase invalid data returned by device

The current definition of wksidarr works fine on little endian arches
(since cpu_to_le32 is a no-op there), but on big-endian arches, it fails
to compile with this error:

error: braced-group within expression allowed only inside a function

The problem is that this static declaration has cpu_to_le32 embedded
within it, and that expands into a function macro.  We need to use
__constant_cpu_to_le32() instead.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Cc: Steven French <sfrench@us.ibm.com>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Try this:

    mount a share with unix extensions
    create a file on it
    umount the share

You'll get the following message in the ring buffer:

VFS: Busy inodes after unmount of cifs. Self-destruct in 5 seconds.  Have a
nice day...

...the problem is that cifs_get_inode_info_unix is creating and hashing
a new inode even when it's going to return error anyway. The first
lookup when creating a file returns an error so we end up leaking this
inode before we do the actual create. This appears to be a regression
caused by commit 0e4bbde9.

The following patch seems to fix it for me, and fixes a minor
formatting nit as well.
Signed-off-by: NJeff Layton <jlayton@redhat.com>
Acked-by: NSteven French <sfrench@us.ibm.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix FRV irqs_disabled() to return an int, not an unsigned long to avoid
this warning:

kernel/sched.c: In function '__might_sleep':
kernel/sched.c:8198: warning: format '%d' expects type 'int', but argument 3 has type 'long unsigned int'
Signed-off-by: NDavid Howells <dhowells@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Cc: Philippe Elie <phil.el@wanadoo.fr>
Cc: John Levon <levon@movementarian.org>
Cc: Maynard Johnson <maynardj@us.ibm.com>
Cc: Richard Purdie <rpurdie@openedhand.com>
Cc: Daniel Hansel <daniel.hansel@linux.vnet.ibm.com>
Cc: Jason Yeh <jason.yeh@amd.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: NRobert Richter <robert.richter@amd.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Add the rtc8564 chip entry
Signed-off-by: NJon Smirl <jonsmirl@gmail.com>
Signed-off-by: NAlessandro Zummo <a.zummo@towertech.it>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Fix chip naming from fm3031-rtc to fm3031
Signed-off-by: NAlessandro Zummo <a.zummo@towertech.it>
Cc: Sergey Lapin <slapin@ossfans.org>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Cortland Setlow pointed out a bug in ov7670.c where the result from
ov7670_read() was just being checked for !0, rather than <0.  This made me
realize that ov7670_read's semantics were rather confusing; it both fills
in 'value' with the result, and returns it.  This is goes against general
kernel convention; so rather than fixing callers, let's fix the function.

This makes ov7670_read return <0 in the case of an error, and 0 upon
success. Thus, code like:

res = ov7670_read(...);
if (!res)
	goto error;

..will work properly.
Signed-off-by: NCortland Setlow <csetlow@tower-research.com>
Signed-off-by: NAndres Salomon <dilinger@debian.org>
Acked-by: NJonathan Corbet <corbet@lwn.net>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

I had 8250.nr_uarts=16 in the boot line of a test kernel and I had a weird
mysterious crash in sysfs.  After taking an in-depth look I realized that
CONFIG_SERIAL_8250_NR_UARTS was set to 4 and I was walking off the end of
the serial8250_ports array.

Ouch!!!

Don't let this happen to someone else.
Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
Acked-by: NAlan Cox <alan@redhat.com>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

This patch is a bugfix for how defio handles multiple processes manipulating
the same framebuffer.

Thanks to Bernard Blackham for identifying this bug.

It occurs when two applications mmap the same framebuffer and concurrently
write to the same page.  Normally, this doesn't occur since only a single
process mmaps the framebuffer.  The symptom of the bug is that the mapping
applications will hang.  The cause is that defio incorrectly tries to add the
same page twice to the pagelist.  The solution I have is to walk the pagelist
and check for a duplicate before adding.  Since I needed to walk the pagelist,
I now also keep the pagelist in sorted order.
Signed-off-by: NJaya Kumar <jayakumar.lkml@gmail.com>
Cc: Bernard Blackham <bernard@largestprime.net>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Coverity CID: 1356 RESOURCE_LEAK

I found a very old patch for this that was Acked but did not get applied
https://lists.linux-foundation.org/pipermail/kernel-janitors/2006-September/016362.html

There looks to be a small leak in isdn_writebuf_stub() in isdn_common.c, when
copy_from_user() returns an un-copied data length (length != 0).  The below
patch should be a minimally invasive fix.
Signed-off-by: NDarren Jenkins <darrenrjenkins@gmailcom>
Acked-by: NKarsten Keil <kkeil@suse.de>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Coverity CID: 2172 RESOURCE_LEAK

When pool_allocate() tries to enlarge a packet, if it can not allocate enough
memory, it returns NULL without first freeing the old packet.

This patch just frees the packet first.
Signed-off-by: NDarren Jenkins <darrenrjenkins@gmail.com>
Acked-by: NJiri Kosina <jkosina@suse.cz>
Cc: <stable@kernel.org>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

If you do a modremove of any sas driver, you run into an oops on
shutdown when the host is removed (coming from the host bsg device).
The root cause seems to be that there's a use after free of the
bsg_class_device:  In bsg_kref_release_function, this is used (to do a
put_device(bcg->parent) after bcg->release has been called.  In sas (and
possibly many other things) bcd->release frees the queue which contains
the bsg_class_device, so we get a put_device on unreferenced memory.
Fix this by taking a copy of the pointer to the parent before releasing
bsg.
Acked-by: NFUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

There's a fault on the FC controllers that makes them not respond
correctly to MSI.  The SPI controllers are fine, but are likely to be
onboard on older motherboards which don't handle MSI correctly, so
default both these cases to disabled.  Enable by setting the module
parameter mpt_msi_enable=1.

For the SAS case, enable MSI by default, but it can be disabled by
setting the module parameter mpt_msi_enable=0.

Cc: "Prakash, Sathya" <sathya.prakash@lsi.com>
Signed-off-by: NJames Bottomley <James.Bottomley@HansenPartnership.com>

Fix size of LDT entries. On x86-64, ldt_desc is a double-sized descriptor.
Signed-off-by: NMichael Karcher <kernel@mkarcher.dialup.fu-berlin.de>
Signed-off-by: NIngo Molnar <mingo@elte.hu>