Pull block fixes from Jens Axboe:
"Make the block layer great again.
Basically three amazing fixes in this pull request, split into 4
patches. Believe me, they should go into 4.4. Two of them fix a
regression, the third and last fixes an easy-to-trigger bug.
- Fix a bad irq enable through null_blk, for queue_mode=1 and using
timer completions. Add a block helper to restart a queue
asynchronously, and use that from null_blk. From me.
- Fix a performance issue in NVMe. Some devices (Intel Pxxxx) expose
a stripe boundary, and performance suffers if we cross it. We took
that into account for merging, but not for the newer splitting
code. Fix from Keith.
- Fix a kernel oops in lightnvm with multiple channels. From Matias"
* 'for-linus' of git://git.kernel.dk/linux-block:
lightnvm: wrong offset in bad blk lun calculation
null_blk: use async queue restart helper
block: add blk_start_queue_async()
block: Split bios on chunk boundaries
c6169202e4