Merge branch 'hughd-fixes' (patches from Hugh Dickins)

Merge VM fixes from High Dickins:
 "I get the impression that Andrew is away or busy at the moment, so I'm
  going to send you three independent uncontroversial little mm fixes
  directly - though none is strictly a 4.8 regression fix.

   - shmem: fix tmpfs to handle the huge= option properly from Toshi
     Kani is a one-liner to fix a major embarrassment in 4.8's hugepages
     on tmpfs feature: although Hillf pointed it out in June, somehow
     both Kirill and I repeatedly dropped the ball on this one.  You
     might wonder if the feature got tested at all with that bug in:
     yes, it did, but for wider testing coverage, Kirill and I had each
     relied too much on an override which bypasses that condition.

   - huge tmpfs: fix Committed_AS leak just a run-of-the-mill accounting
     fix in the same feature.

   - mm: delete unnecessary and unsafe init_tlb_ubc() is an unrelated
     fix to 4.3's TLB flush batching in reclaim: the bug would be rare,
     and none of us will be shamed if this one misses 4.8; but it got
     such a quick ack from Mel today that I'm inclined to offer it along
     with the first two"

* emailed patches from Hugh Dickins <hughd@google.com>:
  mm: delete unnecessary and unsafe init_tlb_ubc()
  huge tmpfs: fix Committed_AS leak
  shmem: fix tmpfs to handle the huge= option properly

mm/shmem.c

@@ -270,7 +270,7 @@ bool shmem_charge(struct inode *inode, long pages)
 		info->alloced -= pages;
 		shmem_recalc_inode(inode);
 		spin_unlock_irqrestore(&info->lock, flags);
-
+		shmem_unacct_blocks(info->flags, pages);
 		return false;
 	}
 	percpu_counter_add(&sbinfo->used_blocks, pages);
@@ -291,6 +291,7 @@ void shmem_uncharge(struct inode *inode, long pages)
 
 	if (sbinfo->max_blocks)
 		percpu_counter_sub(&sbinfo->used_blocks, pages);
+	shmem_unacct_blocks(info->flags, pages);
 }
 
 /*
@@ -1980,7 +1981,7 @@ unsigned long shmem_get_unmapped_area(struct file *file,
 				return addr;
 			sb = shm_mnt->mnt_sb;
 		}
-		if (SHMEM_SB(sb)->huge != SHMEM_HUGE_NEVER)
+		if (SHMEM_SB(sb)->huge == SHMEM_HUGE_NEVER)
 			return addr;
 	}
 

mm/vmscan.c

@@ -2303,23 +2303,6 @@ out:
 	}
 }
 
-#ifdef CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
-static void init_tlb_ubc(void)
-{
-	/*
-	 * This deliberately does not clear the cpumask as it's expensive
-	 * and unnecessary. If there happens to be data in there then the
-	 * first SWAP_CLUSTER_MAX pages will send an unnecessary IPI and
-	 * then will be cleared.
-	 */
-	current->tlb_ubc.flush_required = false;
-}
-#else
-static inline void init_tlb_ubc(void)
-{
-}
-#endif /* CONFIG_ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH */
-
 /*
  * This is a basic per-node page freer.  Used by both kswapd and direct reclaim.
  */
@@ -2355,8 +2338,6 @@ static void shrink_node_memcg(struct pglist_data *pgdat, struct mem_cgroup *memc
 	scan_adjusted = (global_reclaim(sc) && !current_is_kswapd() &&
 			 sc->priority == DEF_PRIORITY);
 
-	init_tlb_ubc();
-
 	blk_start_plug(&plug);
 	while (nr[LRU_INACTIVE_ANON] || nr[LRU_ACTIVE_FILE] ||
 					nr[LRU_INACTIVE_FILE]) {