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

* 'for-linus' of git://git.kernel.dk/linux-block:
  floppy: use del_timer_sync() in init cleanup
  blk-cgroup: be able to remove the record of unplugged device
  block: Don't check QUEUE_FLAG_SAME_COMP in __blk_complete_request
  mm: Add comment explaining task state setting in bdi_forker_thread()
  mm: Cleanup clearing of BDI_pending bit in bdi_forker_thread()
  block: simplify force plug flush code a little bit
  block: change force plug flush call order
  block: Fix queue_flag update when rq_affinity goes from 2 to 1
  block: separate priority boosting from REQ_META
  block: remove READ_META and WRITE_META
  xen-blkback: fixed indentation and comments
  xen-blkback: Don't disconnect backend until state switched to XenbusStateClosed.

21 files changed, 92 insertions, 78 deletions

diff --git a/block/blk-cgroup.c b/block/blk-cgroup.c
index bcaf16ee6ad1..b596e54ddd71 100644
--- a/block/blk-cgroup.c
+++ b/block/blk-cgroup.c
@@ -785,10 +785,10 @@ static int blkio_policy_parse_and_set(char *buf,
 {
         char *s[4], *p, *major_s = NULL, *minor_s = NULL;
         int ret;
-        unsigned long major, minor, temp;
+        unsigned long major, minor;
         int i = 0;
         dev_t dev;
-        u64 bps, iops;
+        u64 temp;
 
         memset(s, 0, sizeof(s));
 
@@ -826,20 +826,23 @@ static int blkio_policy_parse_and_set(char *buf,
 
         dev = MKDEV(major, minor);
 
-        ret = blkio_check_dev_num(dev);
+        ret = strict_strtoull(s[1], 10, &temp);
         if (ret)
-                return ret;
+                return -EINVAL;
 
-        newpn->dev = dev;
+        /* For rule removal, do not check for device presence. */
+        if (temp) {
+                ret = blkio_check_dev_num(dev);
+                if (ret)
+                        return ret;
+        }
 
-        if (s[1] == NULL)
-                return -EINVAL;
+        newpn->dev = dev;
 
         switch (plid) {
         case BLKIO_POLICY_PROP:
-                ret = strict_strtoul(s[1], 10, &temp);
-                if (ret || (temp < BLKIO_WEIGHT_MIN && temp > 0) ||
-                        temp > BLKIO_WEIGHT_MAX)
+                if ((temp < BLKIO_WEIGHT_MIN && temp > 0) ||
+                     temp > BLKIO_WEIGHT_MAX)
                         return -EINVAL;
 
                 newpn->plid = plid;
@@ -850,26 +853,18 @@ static int blkio_policy_parse_and_set(char *buf,
                 switch(fileid) {
                 case BLKIO_THROTL_read_bps_device:
                 case BLKIO_THROTL_write_bps_device:
-                        ret = strict_strtoull(s[1], 10, &bps);
-                        if (ret)
-                                return -EINVAL;
-
                         newpn->plid = plid;
                         newpn->fileid = fileid;
-                        newpn->val.bps = bps;
+                        newpn->val.bps = temp;
                         break;
                 case BLKIO_THROTL_read_iops_device:
                 case BLKIO_THROTL_write_iops_device:
-                        ret = strict_strtoull(s[1], 10, &iops);
-                        if (ret)
-                                return -EINVAL;
-
-                        if (iops > THROTL_IOPS_MAX)
+                        if (temp > THROTL_IOPS_MAX)
                                 return -EINVAL;
 
                         newpn->plid = plid;
                         newpn->fileid = fileid;
-                        newpn->val.iops = (unsigned int)iops;
+                        newpn->val.iops = (unsigned int)temp;
                         break;
                 }
                 break;
diff --git a/block/blk-core.c b/block/blk-core.c
index 90e1ffdeb415..b2ed78afd9f0 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -1167,7 +1167,7 @@ static bool bio_attempt_front_merge(struct request_queue *q,
  * true if merge was successful, otherwise false.
  */
 static bool attempt_plug_merge(struct task_struct *tsk, struct request_queue *q,
-                               struct bio *bio)
+                               struct bio *bio, unsigned int *request_count)
 {
         struct blk_plug *plug;
         struct request *rq;
@@ -1176,10 +1176,13 @@ static bool attempt_plug_merge(struct task_struct *tsk, struct request_queue *q,
         plug = tsk->plug;
         if (!plug)
                 goto out;
+        *request_count = 0;
 
         list_for_each_entry_reverse(rq, &plug->list, queuelist) {
                 int el_ret;
 
+                (*request_count)++;
+
                 if (rq->q != q)
                         continue;
 
@@ -1219,6 +1222,7 @@ static int __make_request(struct request_queue *q, struct bio *bio)
         struct blk_plug *plug;
         int el_ret, rw_flags, where = ELEVATOR_INSERT_SORT;
         struct request *req;
+        unsigned int request_count = 0;
 
         /*
          * low level driver can indicate that it wants pages above a
@@ -1237,7 +1241,7 @@ static int __make_request(struct request_queue *q, struct bio *bio)
          * Check if we can merge with the plugged list before grabbing
          * any locks.
          */
-        if (attempt_plug_merge(current, q, bio))
+        if (attempt_plug_merge(current, q, bio, &request_count))
                 goto out;
 
         spin_lock_irq(q->queue_lock);
@@ -1302,11 +1306,10 @@ get_rq:
                         if (__rq->q != q)
                                 plug->should_sort = 1;
                 }
+                if (request_count >= BLK_MAX_REQUEST_COUNT)
+                        blk_flush_plug_list(plug, false);
                 list_add_tail(&req->queuelist, &plug->list);
-                plug->count++;
                 drive_stat_acct(req, 1);
-                if (plug->count >= BLK_MAX_REQUEST_COUNT)
-                        blk_flush_plug_list(plug, false);
         } else {
                 spin_lock_irq(q->queue_lock);
                 add_acct_request(q, req, where);
@@ -2634,7 +2637,6 @@ void blk_start_plug(struct blk_plug *plug)
         INIT_LIST_HEAD(&plug->list);
         INIT_LIST_HEAD(&plug->cb_list);