mmc: core: mmc sanitize feature support for v4.5

In the v4.5, there's no secure erase & trim support.
Instead it supports the sanitize feature.

Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
 mmc: core: new discard feature support at eMMC v4.5

MMC v4.5 supports the DISCARD feature (CMD38).  It's different from
trim and there's no check bit.  Currently it's only supported at v4.5.

Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
Merge https://github.com/bsmitty83/DirtyV_tuna into SmittyV-eXp4
mmc: core: Detect eMMC v4.5 ext_csd entries

The eMMC v4.5 Spec is released now:

EXT_CSD_REV	Extended CSD Revision
255-7		Reserved
6		Revision 1.6 (for MMC v4.5)
5		Revision 1.5 (for MMV v4.41)
...

Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Chris Ball <cjb@laptop.org>
mmc: core: eMMC 4.5 Power Class Selection Feature

This patch adds the power class selection feature available for mmc
versions 4.0 and above.  During the enumeration stage before switching
to the lower data bus, check if the power class is supported for the
current bus width. If the power class is available then switch to the
power class and use the higher data bus. If power class is not supported
then switch to the lower data bus in a worst case.

Signed-off-by: Girish K S <girish.shivananjappa@linaro.org>
Signed-off-by: Chris Ball <cjb@laptop.org>
f2fs security enabled
Merge https://github.com/bsmitty83/DirtyV_tuna into SmittyV-eXp4
 mm: mempolicy: Convert shared_policy mutex to spinlock

Sasha was fuzzing with trinity and reported the following problem:

  BUG: sleeping function called from invalid context at kernel/mutex.c:269
  in_atomic(): 1, irqs_disabled(): 0, pid: 6361, name: trinity-main
  2 locks held by trinity-main/6361:
   #0:  (&mm->mmap_sem){++++++}, at: [<ffffffff810aa314>] __do_page_fault+0x1e4/0x4f0
   #1:  (&(&mm->page_table_lock)->rlock){+.+...}, at: [<ffffffff8122f017>] handle_pte_fault+0x3f7/0x6a0
  Pid: 6361, comm: trinity-main Tainted: G        W
  3.7.0-rc2-next-20121024-sasha-00001-gd95ef01-dirty #74
  Call Trace:
    __might_sleep+0x1c3/0x1e0
    mutex_lock_nested+0x29/0x50
    mpol_shared_policy_lookup+0x2e/0x90
    shmem_get_policy+0x2e/0x30
    get_vma_policy+0x5a/0xa0
    mpol_misplaced+0x41/0x1d0
    handle_pte_fault+0x465/0x6a0

This was triggered by a different version of automatic NUMA balancing
but in theory the current version is vunerable to the same problem.

do_numa_page
  -> numa_migrate_prep
    -> mpol_misplaced
      -> get_vma_policy
        -> shmem_get_policy

It's very unlikely this will happen as shared pages are not marked
pte_numa -- see the page_mapcount() check in change_pte_range() -- but
it is possible.

To address this, this patch restores sp->lock as originally implemented
by Kosaki Motohiro.  In the path where get_vma_policy() is called, it
should not be calling sp_alloc() so it is not necessary to treat the PTL
specially.

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Tested-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>