ASoC: Intel: Fix build with CONFIG_SLEEP enabled.

Fix the following build error when CONFIG_SLEEP is enabled and CONFIG_RUNTIME
is disabled. The BDW ADSP sleep PM functionality depends on the runtime pm
calls for context save/restore.

All error/warnings:

>> ERROR: "snd_soc_suspend" undefined!
>> ERROR: "snd_soc_resume" undefined!

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Liam Girdwood <liam.r.girdwood@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
block: Expand a bit documentation about elevator_allow_merge_fn

Explain that two requests can be merged without
elevator_allow_merge_fn() being called.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@fb.com>
arch: tile: kernel: signal.c: Use __copy_from/to_user() instead of __get/put_user()

setup/restore_sigcontext() want to copy all related registers between
user and kernel. So use block copy instead of each registers copy. Then
can let code simple and clearer (which can avoid compiler's warning):

The related warning (with allmodconfig under tile):

    CC      arch/tile/kernel/signal.o
  In file included from include/linux/poll.h:11:0,
                   from include/linux/ring_buffer.h:7,
                   from include/linux/ftrace_event.h:5,
                   from include/trace/syscall.h:6,
                   from include/linux/syscalls.h:81,
                   from arch/tile/kernel/signal.c:30:
  arch/tile/kernel/signal.c: In function 'setup_sigcontext':
  arch/tile/kernel/signal.c:116:31: warning: iteration 53u invokes undefined behavior [-Waggressive-loop-optimizations]
     err |= __put_user(regs->regs[i], &sc->gregs[i]);
                                 ^
  ./arch/tile/include/asm/uaccess.h:236:26: note: in definition of macro '__put_user_asm'
          : "r" (ptr), "r" (x), "i" (-EFAULT))
                            ^
  ./arch/tile/include/asm/uaccess.h:297:10: note: in expansion of macro '__put_user_8'
    case 8: __put_user_8(x, ptr, __ret); break;   \
            ^
  arch/tile/kernel/signal.c:116:10: note: in expansion of macro '__put_user'
     err |= __put_user(regs->regs[i], &sc->gregs[i]);
            ^
  arch/tile/kernel/signal.c:115:2: note: containing loop
    for (i = 0; i < sizeof(struct pt_regs)/sizeof(long); ++i)
    ^

Signed-off-by: Chen Gang <gang.chen.5i5j@gmail.com>
Signed-off-by: Chris Metcalf <cmetcalf@tilera.com>
Merge branch 'for-3.19/core' into for-next
Merge branch 'irq/urgent'
Merge branch 'perf/core'
Merge branch 'perf/urgent'
Merge branch 'sched/core'
Merge branch 'sched/urgent'
Merge branch 'timers/2038'
Merge branch 'x86/apic'
Merge branch 'x86/asm'
Merge branch 'x86/boot'
Merge branch 'x86/build'
Merge branch 'x86/cleanups'
Merge branch 'x86/mm'
Merge branch 'x86/ras'
Merge branch 'x86/urgent'
Merge branch 'x86/uv'
Merge branch 'x86/vdso'