ahci: disable DEVSLP for Intel Valleyview

On Intel Valleyview SoC, SATA device sleep is not reliable. When
DEVSLP is attempted on certain SSDs, port_devslp write would fail
and result in malfunction of AHCI controller. AHCI controller may
be not shown in PCI enumeration after reset. Complete power source
removal may be required to recover from this failure. So we blacklist
this device and override host device reported capabilities such that
device LPM will only attempt slumber but not DEVSLP.

Signed-off-by: Jacob Pan <jacob.jun.pan@linux.intel.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
crypto: caam - add allocation failure handling in SPRINTFCAT macro

GFP_ATOMIC memory allocation could fail.
In this case, avoid NULL pointer dereference and notify user.

Cc: <stable@vger.kernel.org> # 3.2+
Cc: Kim Phillips <kim.phillips@freescale.com>
Signed-off-by: Horia Geanta <horia.geanta@freescale.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
ahci: imx: add namespace for register enums

Update register enums a little bit to add proper namespace prefix, and
have the names match i.MX reference manual.

Signed-off-by: Shawn Guo <shawn.guo@freescale.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
ahci: imx: software workaround for phy reset issue in resume

When suspending imx6q systems which have rootfs on SATA, the following
error will likely be seen in resume.  The SATA link will fail to come
up, and it results in an unusable system across the suspend/resume
cycle.

$ echo mem > /sys/power/state
PM: Syncing filesystems ... done.
PM: Preparing system for mem sleep
Freezing user space processes ... (elapsed 0.002 seconds) done.
Freezing remaining freezable tasks ... (elapsed 0.002 seconds) done.
PM: Entering mem sleep
sd 0:0:0:0: [sda] Synchronizing SCSI cache
sd 0:0:0:0: [sda] Stopping disk
PM: suspend of devices complete after 61.914 msecs
PM: suspend devices took 0.070 seconds
PM: late suspend of devices complete after 4.906 msecs
PM: noirq suspend of devices complete after 4.521 msecs
Disabling non-boot CPUs ...
CPU1: shutdown
CPU2: shutdown
CPU3: shutdown
Enabling non-boot CPUs ...
CPU1: Booted secondary processor
CPU1 is up
CPU2: Booted secondary processor
CPU2 is up
CPU3: Booted secondary processor
CPU3 is up
PM: noirq resume of devices complete after 10.486 msecs
PM: early resume of devices complete after 4.679 msecs
sd 0:0:0:0: [sda] Starting disk
PM: resume of devices complete after 22.674 msecs
PM: resume devices took 0.030 seconds
PM: Finishing wakeup.
Restarting tasks ... done.
$ ata1: SATA link down (SStatus 1 SControl 300)
ata1: SATA link down (SStatus 1 SControl 300)
ata1: limiting SATA link speed to 1.5 Gbps
ata1: SATA link down (SStatus 1 SControl 310)
ata1.00: disabled
ata1: exception Emask 0x10 SAct 0x0 SErr 0x4040000 action 0xe frozen t4
ata1: irq_stat 0x00000040, connection status changed
ata1: SError: { CommWake DevExch }
ata1: hard resetting link
sd 0:0:0:0: rejecting I/O to offline device
sd 0:0:0:0: killing request
sd 0:0:0:0: rejecting I/O to offline device
Aborting journal on device sda2-8.
sd 0:0:0:0: rejecting I/O to offline device
EXT4-fs warning (device sda2): ext4_end_bio:317: I/O error writing to inode 132577 (offset 0 size 0 starting block 26235)
Buffer I/O error on device sda2, logical block 10169
...

It's caused by a silicon issue that SATA phy does not get reset by
controller when coming back from LPM.  The patch adds a software
workaround for this issue.  It enforces a software reset on SATA phy
in imx_sata_enable() function, so that we can ensure SATA link will
come up properly in both power-on and resume.

The software reset is implemented by writing phy reset register through
the phy control register bus interface.  Functions
imx_phy_reg_[addressing|write|read]() implement this bus interface, while
imx_sata_phy_reset() performs the actually reset operation.

Signed-off-by: Richard Zhu <r65037@freescale.com>
Signed-off-by: Shawn Guo <shawn.guo@freescale.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
libata: clean up ZPODD when a port is detached

When a ZPODD device is unbound via sysfs, the ACPI notify handler
is not removed. This causes panics as observed in Bug #74601. The
panic only happens when the wake happens from outside the kernel
(i.e. inserting a media or pressing a button). Add a loop to
ata_port_detach which loops through the port's devices and checks
if zpodd is enabled, if so call zpodd_exit.

Cc: stable@vger.kernel.org
Reviewed-by: Aaron Lu <aaron.lu@intel.com>
Signed-off-by: Levente Kurusa <levex@linux.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
crypto: s390 - fix aes,des ctr mode concurrency finding.

An additional testcase found an issue with the last
series of patches applied: the fallback solution may
not save the iv value after operation. This very small
fix just makes sure the iv is copied back to the
walk/desc struct.

Cc: <stable@vger.kernel.org> # 3.14+
Signed-off-by: Harald Freudenberger <freude@linux.vnet.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
ata: pata_at91 only works on sam9

The smc driver used by pata_at91 is at91sam9 specific, so building
this driver on another at91 platform results in this error:

ERROR: "sam9_smc_configure" [drivers/ata/pata_at91.ko] undefined!
ERROR: "sam9_smc_write_mode" [drivers/ata/pata_at91.ko] undefined!
ERROR: "sam9_smc_read_mode" [drivers/ata/pata_at91.ko] undefined!

This patch changes the Kconfig dependency to ensure it always works.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: linux-ide@vger.kernel.org
Cc: Jean-Christophe Plagniol-Villard <plagnioj@jcrosoft.com>
Cc: Nicolas Ferre <nicolas.ferre@atmel.com>
cgroup: introduce task_css_is_root()

Determining the css of a task usually requires RCU read lock as that's
the only thing which keeps the returned css accessible till its
reference is acquired; however, testing whether a task belongs to the
root can be performed without dereferencing the returned css by
comparing the returned pointer against the root one in init_css_set[]
which never changes.

Implement task_css_is_root() which can be invoked in any context.
This will be used by the scheduled cgroup_freezer change.

v2: cgroup no longer supports modular controllers.  No need to export
    init_css_set.  Pointed out by Li.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
cgroup_freezer: replace freezer->lock with freezer_mutex

After 96d365e0b86e ("cgroup: make css_set_lock a rwsem and rename it
to css_set_rwsem"), css task iterators requires sleepable context as
it may block on css_set_rwsem.  I missed that cgroup_freezer was
iterating tasks under IRQ-safe spinlock freezer->lock.  This leads to
errors like the following on freezer state reads and transitions.

  BUG: sleeping function called from invalid context at /work
 /os/work/kernel/locking/rwsem.c:20
  in_atomic(): 0, irqs_disabled(): 0, pid: 462, name: bash
  5 locks held by bash/462:
   #0:  (sb_writers#7){.+.+.+}, at: [<ffffffff811f0843>] vfs_write+0x1a3/0x1c0
   #1:  (&of->mutex){+.+.+.}, at: [<ffffffff8126d78b>] kernfs_fop_write+0xbb/0x170
   #2:  (s_active#70){.+.+.+}, at: [<ffffffff8126d793>] kernfs_fop_write+0xc3/0x170
   #3:  (freezer_mutex){+.+...}, at: [<ffffffff81135981>] freezer_write+0x61/0x1e0
   #4:  (rcu_read_lock){......}, at: [<ffffffff81135973>] freezer_write+0x53/0x1e0
  Preemption disabled at:[<ffffffff81104404>] console_unlock+0x1e4/0x460

  CPU: 3 PID: 462 Comm: bash Not tainted 3.15.0-rc1-work+ #10
  Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011
   ffff88000916a6d0 ffff88000e0a3da0 ffffffff81cf8c96 0000000000000000
   ffff88000e0a3dc8 ffffffff810cf4f2 ffffffff82388040 ffff880013aaf740
   0000000000000002 ffff88000e0a3de8 ffffffff81d05974 0000000000000246
  Call Trace:
   [<ffffffff81cf8c96>] dump_stack+0x4e/0x7a
   [<ffffffff810cf4f2>] __might_sleep+0x162/0x260
   [<ffffffff81d05974>] down_read+0x24/0x60
   [<ffffffff81133e87>] css_task_iter_start+0x27/0x70
   [<ffffffff8113584d>] freezer_apply_state+0x5d/0x130
   [<ffffffff81135a16>] freezer_write+0xf6/0x1e0
   [<ffffffff8112eb88>] cgroup_file_write+0xd8/0x230
   [<ffffffff8126d7b7>] kernfs_fop_write+0xe7/0x170
   [<ffffffff811f0756>] vfs_write+0xb6/0x1c0
   [<ffffffff811f121d>] SyS_write+0x4d/0xc0
   [<ffffffff81d08292>] system_call_fastpath+0x16/0x1b

freezer->lock used to be used in hot paths but that time is long gone
and there's no reason for the lock to be IRQ-safe spinlock or even
per-cgroup.  In fact, given the fact that a cgroup may contain large
number of tasks, it's not a good idea to iterate over them while
holding IRQ-safe spinlock.

Let's simplify locking by replacing per-cgroup freezer->lock with
global freezer_mutex.  This also makes the comments explaining the
intricacies of policy inheritance and the locking around it as the
states are protected by a common mutex.

The conversion is mostly straight-forward.  The followings are worth
mentioning.

* freezer_css_online() no longer needs double locking.

* freezer_attach() now performs propagation simply while holding
  freezer_mutex.  update_if_frozen() race no longer exists and the
  comment is removed.

* freezer_fork() now tests whether the task is in root cgroup using
  the new task_css_is_root() without doing rcu_read_lock/unlock().  If
  not, it grabs freezer_mutex and performs the operation.

* freezer_read() and freezer_change_state() grab freezer_mutex across
  the whole operation and pin the css while iterating so that each
  descendant processing happens in sleepable context.

Fixes: 96d365e0b86e ("cgroup: make css_set_lock a rwsem and rename it to css_set_rwsem")
Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Li Zefan <lizefan@huawei.com>
cgroup: fix rcu_read_lock() leak in update_if_frozen()

While updating cgroup_freezer locking, 68fafb77d827 ("cgroup_freezer:
replace freezer->lock with freezer_mutex") introduced a bug in
update_if_frozen() where it returns with rcu_read_lock() held.  Fix it
by adding rcu_read_unlock() before returning.

Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: kbuild test robot <fengguang.wu@intel.com>
ahci: imx: PLL clock needs 100us to settle down

The commit e783c51 (ahci: imx: software workaround for phy reset issue
in resume) calls imx_sata_phy_reset() to reset phy immediately after
SATA MPLL is enabled.  It seems working fine mostly, but fails in some
case as below.

...
ahci-imx 2200000.sata: failed to reset phy: -110
ahci-imx: probe of 2200000.sata failed with error -110

After talking to the designer, we learnt that when enabling i.MX6Q SATA
MPLL, we need to wait 100us for it to settle down for safety.  Add this
required delay to fix above failure.

Signed-off-by: Shawn Guo <shawn.guo@freescale.com>
Tested-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6

Pull crypto fixes from Herbert Xu:
 "This fixes a NULL pointer dereference on allocation failure in caam,
  as well as a regression in the ctr mode on s390 that was added with
  the recent concurrency fixes"

* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: s390 - fix aes,des ctr mode concurrency finding.
  crypto: caam - add allocation failure handling in SPRINTFCAT macro
Merge branch 'for-3.15-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata

Pull libata fixes from Tejun Heo:
 "Mostly device-specific fixes.  The only thing which isn't is the fix
  for zpodd oops-on-detach bug"

* 'for-3.15-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/libata:
  ahci: imx: PLL clock needs 100us to settle down
  ata: pata_at91 only works on sam9
  libata: clean up ZPODD when a port is detached
  ahci: imx: software workaround for phy reset issue in resume
  ahci: imx: add namespace for register enums
  ahci: disable DEVSLP for Intel Valleyview
Merge branch 'for-3.15-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup

Pull more cgroup fixes from Tejun Heo:
 "Three more patches to fix cgroup_freezer breakage due to the recent
  cgroup internal locking changes - an operation cgroup_freezer was
  using now requires sleepable context and cgroup_freezer was invoking
  that while holding a spin lock.  cgroup_freezer was using an overly
  elaborate hierarchical locking scheme.

  While it's possible to convert the hierarchical spinlocks directly to
  mutexes, this patch simplifies the overall locking so that it uses a
  global mutex.  This has the added benefit of avoiding iterating
  potentially huge number of tasks under a spinlock.  While the patch is
  on the larger side in the devel cycle, the changes made are mostly
  straight-forward and the locking logic is a lot simpler afterwards"

* 'for-3.15-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
  cgroup: fix rcu_read_lock() leak in update_if_frozen()
  cgroup_freezer: replace freezer->lock with freezer_mutex
  cgroup: introduce task_css_is_root()