[patch 123/158] hugetlbfs: hugetlb_fault_mutex_hash() cleanup

[akpm@linux-foundation.org]

From: Mike Kravetz <mike.kravetz@oracle.com>
Subject: hugetlbfs: hugetlb_fault_mutex_hash() cleanup

A new clang diagnostic (-Wsizeof-array-div) warns about the calculation to
determine the number of u32's in an array of unsigned longs.  Suppress
warning by adding parentheses.

While looking at the above issue, noticed that the 'address' parameter to
hugetlb_fault_mutex_hash is no longer used.  So, remove it from the
definition and all callers.

No functional change.

Link: http://lkml.kernel.org/r/20190919011847.18400-1-mike.kravetz@oracle.com
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Reported-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Davidlohr Bueso <dbueso@suse.de>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Ilie Halip <ilie.halip@gmail.com>
Cc: David Bolvansky <david.bolvansky@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 fs/hugetlbfs/inode.c    |    4 ++--
 include/linux/hugetlb.h |    2 +-
 mm/hugetlb.c            |   10 +++++-----
 mm/userfaultfd.c        |    2 +-
 4 files changed, 9 insertions(+), 9 deletions(-)

--- a/fs/hugetlbfs/inode.c~hugetlbfs-hugetlb_fault_mutex_hash-cleanup
+++ a/fs/hugetlbfs/inode.c
@@ -440,7 +440,7 @@ static void remove_inode_hugepages(struc
 			u32 hash;
 
 			index = page->index;
-			hash = hugetlb_fault_mutex_hash(h, mapping, index, 0);
+			hash = hugetlb_fault_mutex_hash(h, mapping, index);
 			mutex_lock(&hugetlb_fault_mutex_table[hash]);
 
 			/*
@@ -644,7 +644,7 @@ static long hugetlbfs_fallocate(struct f
 		addr = index * hpage_size;
 
 		/* mutex taken here, fault path and hole punch */
-		hash = hugetlb_fault_mutex_hash(h, mapping, index, addr);
+		hash = hugetlb_fault_mutex_hash(h, mapping, index);
 		mutex_lock(&hugetlb_fault_mutex_table[hash]);
 
 		/* See if already present in mapping to avoid alloc/free */
--- a/include/linux/hugetlb.h~hugetlbfs-hugetlb_fault_mutex_hash-cleanup
+++ a/include/linux/hugetlb.h
@@ -106,7 +106,7 @@ void free_huge_page(struct page *page);
 void hugetlb_fix_reserve_counts(struct inode *inode);
 extern struct mutex *hugetlb_fault_mutex_table;
 u32 hugetlb_fault_mutex_hash(struct hstate *h, struct address_space *mapping,
-				pgoff_t idx, unsigned long address);
+				pgoff_t idx);
 
 pte_t *huge_pmd_share(struct mm_struct *mm, unsigned long addr, pud_t *pud);
 
--- a/mm/hugetlb.c~hugetlbfs-hugetlb_fault_mutex_hash-cleanup
+++ a/mm/hugetlb.c
@@ -3842,7 +3842,7 @@ retry:
 			 * handling userfault.  Reacquire after handling
 			 * fault to make calling code simpler.
 			 */
-			hash = hugetlb_fault_mutex_hash(h, mapping, idx, haddr);
+			hash = hugetlb_fault_mutex_hash(h, mapping, idx);
 			mutex_unlock(&hugetlb_fault_mutex_table[hash]);
 			ret = handle_userfault(&vmf, VM_UFFD_MISSING);
 			mutex_lock(&hugetlb_fault_mutex_table[hash]);
@@ -3970,7 +3970,7 @@ backout_unlocked:
 
 #ifdef CONFIG_SMP
 u32 hugetlb_fault_mutex_hash(struct hstate *h, struct address_space *mapping,
-			    pgoff_t idx, unsigned long address)
+			    pgoff_t idx)
 {
 	unsigned long key[2];
 	u32 hash;
@@ -3978,7 +3978,7 @@ u32 hugetlb_fault_mutex_hash(struct hsta
 	key[0] = (unsigned long) mapping;
 	key[1] = idx;
 
-	hash = jhash2((u32 *)&key, sizeof(key)/sizeof(u32), 0);
+	hash = jhash2((u32 *)&key, sizeof(key)/(sizeof(u32)), 0);
 
 	return hash & (num_fault_mutexes - 1);
 }
@@ -3988,7 +3988,7 @@ u32 hugetlb_fault_mutex_hash(struct hsta
  * return 0 and avoid the hashing overhead.
  */
 u32 hugetlb_fault_mutex_hash(struct hstate *h, struct address_space *mapping,
-			    pgoff_t idx, unsigned long address)
+			    pgoff_t idx)
 {
 	return 0;
 }
@@ -4032,7 +4032,7 @@ vm_fault_t hugetlb_fault(struct mm_struc
 	 * get spurious allocation failures if two CPUs race to instantiate
 	 * the same page in the page cache.
 	 */
-	hash = hugetlb_fault_mutex_hash(h, mapping, idx, haddr);
+	hash = hugetlb_fault_mutex_hash(h, mapping, idx);
 	mutex_lock(&hugetlb_fault_mutex_table[hash]);
 
 	entry = huge_ptep_get(ptep);
--- a/mm/userfaultfd.c~hugetlbfs-hugetlb_fault_mutex_hash-cleanup
+++ a/mm/userfaultfd.c
@@ -269,7 +269,7 @@ retry:
 		 */
 		idx = linear_page_index(dst_vma, dst_addr);
 		mapping = dst_vma->vm_file->f_mapping;
-		hash = hugetlb_fault_mutex_hash(h, mapping, idx, dst_addr);
+		hash = hugetlb_fault_mutex_hash(h, mapping, idx);
 		mutex_lock(&hugetlb_fault_mutex_table[hash]);
 
 		err = -ENOMEM;
_