Merge branch 'for-4.15/block' of git://git.kernel.dk/linux-block

Pull core block layer updates from Jens Axboe:
 "This is the main pull request for block storage for 4.15-rc1.

  Nothing out of the ordinary in here, and no API changes or anything
  like that. Just various new features for drivers, core changes, etc.
  In particular, this pull request contains:

   - A patch series from Bart, closing the whole on blk/scsi-mq queue
     quescing.

   - A series from Christoph, building towards hidden gendisks (for
     multipath) and ability to move bio chains around.

   - NVMe
        - Support for native multipath for NVMe (Christoph).
        - Userspace notifications for AENs (Keith).
        - Command side-effects support (Keith).
        - SGL support (Chaitanya Kulkarni)
        - FC fixes and improvements (James Smart)
        - Lots of fixes and tweaks (Various)

   - bcache
        - New maintainer (Michael Lyle)
        - Writeback control improvements (Michael)
        - Various fixes (Coly, Elena, Eric, Liang, et al)

   - lightnvm updates, mostly centered around the pblk interface
     (Javier, Hans, and Rakesh).

   - Removal of unused bio/bvec kmap atomic interfaces (me, Christoph)

   - Writeback series that fix the much discussed hundreds of millions
     of sync-all units. This goes all the way, as discussed previously
     (me).

   - Fix for missing wakeup on writeback timer adjustments (Yafang
     Shao).

   - Fix laptop mode on blk-mq (me).

   - {mq,name} tupple lookup for IO schedulers, allowing us to have
     alias names. This means you can use 'deadline' on both !mq and on
     mq (where it's called mq-deadline). (me).

   - blktrace race fix, oopsing on sg load (me).

   - blk-mq optimizations (me).

   - Obscure waitqueue race fix for kyber (Omar).

   - NBD fixes (Josef).

   - Disable writeback throttling by default on bfq, like we do on cfq
     (Luca Miccio).

   - Series from Ming that enable us to treat flush requests on blk-mq
     like any other request. This is a really nice cleanup.

   - Series from Ming that improves merging on blk-mq with schedulers,
     getting us closer to flipping the switch on scsi-mq again.

   - BFQ updates (Paolo).

   - blk-mq atomic flags memory ordering fixes (Peter Z).

   - Loop cgroup support (Shaohua).

   - Lots of minor fixes from lots of different folks, both for core and
     driver code"

* 'for-4.15/block' of git://git.kernel.dk/linux-block: (294 commits)
  nvme: fix visibility of "uuid" ns attribute
  blk-mq: fixup some comment typos and lengths
  ide: ide-atapi: fix compile error with defining macro DEBUG
  blk-mq: improve tag waiting setup for non-shared tags
  brd: remove unused brd_mutex
  blk-mq: only run the hardware queue if IO is pending
  block: avoid null pointer dereference on null disk
  fs: guard_bio_eod() needs to consider partitions
  xtensa/simdisk: fix compile error
  nvme: expose subsys attribute to sysfs
  nvme: create 'slaves' and 'holders' entries for hidden controllers
  block: create 'slaves' and 'holders' entries for hidden gendisks
  nvme: also expose the namespace identification sysfs files for mpath nodes
  nvme: implement multipath access to nvme subsystems
  nvme: track shared namespaces
  nvme: introduce a nvme_ns_ids structure
  nvme: track subsystems
  block, nvme: Introduce blk_mq_req_flags_t
  block, scsi: Make SCSI quiesce and resume work reliably
  block: Add the QUEUE_FLAG_PREEMPT_ONLY request queue flag
  ...

1 files changed, 12 insertions, 31 deletions

diff --git a/drivers/lightnvm/pblk-rl.c b/drivers/lightnvm/pblk-rl.c
index 2e6a5361baf0..abae31fd434e 100644
--- a/drivers/lightnvm/pblk-rl.c
+++ b/drivers/lightnvm/pblk-rl.c
@@ -96,9 +96,11 @@ unsigned long pblk_rl_nr_free_blks(struct pblk_rl *rl)
  *
  * Only the total number of free blocks is used to configure the rate limiter.
  */
-static int pblk_rl_update_rates(struct pblk_rl *rl, unsigned long max)
+void pblk_rl_update_rates(struct pblk_rl *rl)
 {
+	struct pblk *pblk = container_of(rl, struct pblk, rl);
 	unsigned long free_blocks = pblk_rl_nr_free_blks(rl);
+	int max = rl->rb_budget;
 
 	if (free_blocks >= rl->high) {
 		rl->rb_user_max = max;
@@ -124,23 +126,18 @@ static int pblk_rl_update_rates(struct pblk_rl *rl, unsigned long max)
 		rl->rb_state = PBLK_RL_LOW;
 	}
 
-	return rl->rb_state;
+	if (rl->rb_state == (PBLK_RL_MID | PBLK_RL_LOW))
+		pblk_gc_should_start(pblk);
+	else
+		pblk_gc_should_stop(pblk);
 }
 
 void pblk_rl_free_lines_inc(struct pblk_rl *rl, struct pblk_line *line)
 {
-	struct pblk *pblk = container_of(rl, struct pblk, rl);
 	int blk_in_line = atomic_read(&line->blk_in_line);
-	int ret;
 
 	atomic_add(blk_in_line, &rl->free_blocks);
-	/* Rates will not change that often - no need to lock update */
-	ret = pblk_rl_update_rates(rl, rl->rb_budget);
-
-	if (ret == (PBLK_RL_MID | PBLK_RL_LOW))
-		pblk_gc_should_start(pblk);
-	else
-		pblk_gc_should_stop(pblk);
+	pblk_rl_update_rates(rl);
 }
 
 void pblk_rl_free_lines_dec(struct pblk_rl *rl, struct pblk_line *line)
@@ -148,19 +145,7 @@ void pblk_rl_free_lines_dec(struct pblk_rl *rl, struct pblk_line *line)
 	int blk_in_line = atomic_read(&line->blk_in_line);
 
 	atomic_sub(blk_in_line, &rl->free_blocks);
-}
-
-void pblk_gc_should_kick(struct pblk *pblk)
-{
-	struct pblk_rl *rl = &pblk->rl;
-	int ret;
-
-	/* Rates will not change that often - no need to lock update */
-	ret = pblk_rl_update_rates(rl, rl->rb_budget);
-	if (ret == (PBLK_RL_MID | PBLK_RL_LOW))
-		pblk_gc_should_start(pblk);
-	else
-		pblk_gc_should_stop(pblk);
+	pblk_rl_update_rates(rl);
 }
 
 int pblk_rl_high_thrs(struct pblk_rl *rl)
@@ -168,14 +153,9 @@ int pblk_rl_high_thrs(struct pblk_rl *rl)
 	return rl->high;
 }
 
-int pblk_rl_low_thrs(struct pblk_rl *rl)
-{
-	return rl->low;
-}
-
-int pblk_rl_sysfs_rate_show(struct pblk_rl *rl)
+int pblk_rl_max_io(struct pblk_rl *rl)
 {
-	return rl->rb_user_max;
+	return rl->rb_max_io;
 }
 
 static void pblk_rl_u_timer(unsigned long data)
@@ -214,6 +194,7 @@ void pblk_rl_init(struct pblk_rl *rl, int budget)
 	/* To start with, all buffer is available to user I/O writers */
 	rl->rb_budget = budget;
 	rl->rb_user_max = budget;
+	rl->rb_max_io = budget >> 1;
 	rl->rb_gc_max = 0;
 	rl->rb_state = PBLK_RL_HIGH;