mm: remove flags argument to mmap_region

After the MAP_POPULATE handling has been moved to mmap_region() call
sites, the only remaining use of the flags argument is to pass the
MAP_NORESERVE flag.  This can be just as easily handled by
do_mmap_pgoff(), so do that and remove the mmap_region() flags
parameter.

[akpm@linux-foundation.org: remove double parens]
Signed-off-by: NMichel Lespinasse <walken@google.com>
Acked-by: NRik van Riel <riel@redhat.com>
Tested-by: NAndy Lutomirski <luto@amacapital.net>
Cc: Greg Ungerer <gregungerer@westnet.com.au>
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

arch/tile/mm/elf.c

@@ -130,7 +130,6 @@ int arch_setup_additional_pages(struct linux_binprm *bprm,
 	if (!retval) {
 		unsigned long addr = MEM_USER_INTRPT;
 		addr = mmap_region(NULL, addr, INTRPT_SIZE,
-				   MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE,
 				   VM_READ|VM_EXEC|
 				   VM_MAYREAD|VM_MAYWRITE|VM_MAYEXEC, 0);
 		if (addr > (unsigned long) -PAGE_SIZE)

include/linux/mm.h

@@ -1472,8 +1472,7 @@ extern int install_special_mapping(struct mm_struct *mm,
 extern unsigned long get_unmapped_area(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
 
 extern unsigned long mmap_region(struct file *file, unsigned long addr,
-	unsigned long len, unsigned long flags,
-	vm_flags_t vm_flags, unsigned long pgoff);
+	unsigned long len, vm_flags_t vm_flags, unsigned long pgoff);
 extern unsigned long do_mmap_pgoff(struct file *file, unsigned long addr,
 	unsigned long len, unsigned long prot, unsigned long flags,
 	unsigned long pgoff, bool *populate);

mm/fremap.c

@@ -204,9 +204,8 @@ SYSCALL_DEFINE5(remap_file_pages, unsigned long, start, unsigned long, size,
 			unsigned long addr;
 			struct file *file = get_file(vma->vm_file);
 
-			flags = (flags & MAP_NONBLOCK) | MAP_POPULATE;
 			addr = mmap_region(file, start, size,
-					flags, vma->vm_flags, pgoff);
+					vma->vm_flags, pgoff);
 			fput(file);
 			if (IS_ERR_VALUE(addr)) {
 				err = addr;

mm/mmap.c

@@ -1291,7 +1291,21 @@ unsigned long do_mmap_pgoff(struct file *file, unsigned long addr,
 		}
 	}
 
-	addr = mmap_region(file, addr, len, flags, vm_flags, pgoff);
+	/*
+	 * Set 'VM_NORESERVE' if we should not account for the
+	 * memory use of this mapping.
+	 */
+	if (flags & MAP_NORESERVE) {
+		/* We honor MAP_NORESERVE if allowed to overcommit */
+		if (sysctl_overcommit_memory != OVERCOMMIT_NEVER)
+			vm_flags |= VM_NORESERVE;
+
+		/* hugetlb applies strict overcommit unless MAP_NORESERVE */
+		if (file && is_file_hugepages(file))
+			vm_flags |= VM_NORESERVE;
+	}
+
+	addr = mmap_region(file, addr, len, vm_flags, pgoff);
 	if (!IS_ERR_VALUE(addr) &&
 	    ((vm_flags & VM_LOCKED) ||
 	     (flags & (MAP_POPULATE | MAP_NONBLOCK)) == MAP_POPULATE))
@@ -1411,8 +1425,7 @@ static inline int accountable_mapping(struct file *file, vm_flags_t vm_flags)
 }
 
 unsigned long mmap_region(struct file *file, unsigned long addr,
-			  unsigned long len, unsigned long flags,
-			  vm_flags_t vm_flags, unsigned long pgoff)
+		unsigned long len, vm_flags_t vm_flags, unsigned long pgoff)
 {
 	struct mm_struct *mm = current->mm;
 	struct vm_area_struct *vma, *prev;
@@ -1435,20 +1448,6 @@ unsigned long mmap_region(struct file *file, unsigned long addr,
 	if (!may_expand_vm(mm, len >> PAGE_SHIFT))
 		return -ENOMEM;
 
-	/*
-	 * Set 'VM_NORESERVE' if we should not account for the
-	 * memory use of this mapping.
-	 */
-	if ((flags & MAP_NORESERVE)) {
-		/* We honor MAP_NORESERVE if allowed to overcommit */
-		if (sysctl_overcommit_memory != OVERCOMMIT_NEVER)
-			vm_flags |= VM_NORESERVE;
-
-		/* hugetlb applies strict overcommit unless MAP_NORESERVE */
-		if (file && is_file_hugepages(file))
-			vm_flags |= VM_NORESERVE;
-	}
-
 	/*
 	 * Private writable mapping: check memory availability
 	 */