mmap locking API: convert mmap_sem comments

Convert comments that reference mmap_sem to reference mmap_lock instead.

[akpm@linux-foundation.org: fix up linux-next leftovers]
[akpm@linux-foundation.org: s/lockaphore/lock/, per Vlastimil]
[akpm@linux-foundation.org: more linux-next fixups, per Michel]

Signed-off-by: Michel Lespinasse <walken@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Laurent Dufour <ldufour@linux.ibm.com>
Cc: Liam Howlett <Liam.Howlett@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ying Han <yinghan@google.com>
Link: http://lkml.kernel.org/r/20200520052908.204642-13-walken@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 18 insertions, 18 deletions

diff --git a/mm/mmap.c b/mm/mmap.c
index 79005049fbfc..59a4682ebf3f 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -132,7 +132,7 @@ void vma_set_page_prot(struct vm_area_struct *vma)
 		vm_flags &= ~VM_SHARED;
 		vm_page_prot = vm_pgprot_modify(vm_page_prot, vm_flags);
 	}
-	/* remove_protection_ptes reads vma->vm_page_prot without mmap_sem */
+	/* remove_protection_ptes reads vma->vm_page_prot without mmap_lock */
 	WRITE_ONCE(vma->vm_page_prot, vm_page_prot);
 }
 
@@ -238,14 +238,14 @@ SYSCALL_DEFINE1(brk, unsigned long, brk)
 
 	/*
 	 * Always allow shrinking brk.
-	 * __do_munmap() may downgrade mmap_sem to read.
+	 * __do_munmap() may downgrade mmap_lock to read.
 	 */
 	if (brk <= mm->brk) {
 		int ret;
 
 		/*
-		 * mm->brk must to be protected by write mmap_sem so update it
-		 * before downgrading mmap_sem. When __do_munmap() fails,
+		 * mm->brk must to be protected by write mmap_lock so update it
+		 * before downgrading mmap_lock. When __do_munmap() fails,
 		 * mm->brk will be restored from origbrk.
 		 */
 		mm->brk = brk;
@@ -505,7 +505,7 @@ static __always_inline void vma_rb_erase(struct vm_area_struct *vma,
  * After the update, the vma will be reinserted using
  * anon_vma_interval_tree_post_update_vma().
  *
- * The entire update must be protected by exclusive mmap_sem and by
+ * The entire update must be protected by exclusive mmap_lock and by
  * the root anon_vma's mutex.
  */
 static inline void
@@ -2371,7 +2371,7 @@ int expand_upwards(struct vm_area_struct *vma, unsigned long address)
 
 	/*
 	 * vma->vm_start/vm_end cannot change under us because the caller
-	 * is required to hold the mmap_sem in read mode.  We need the
+	 * is required to hold the mmap_lock in read mode.  We need the
 	 * anon_vma lock to serialize against concurrent expand_stacks.
 	 */
 	anon_vma_lock_write(vma->anon_vma);
@@ -2389,7 +2389,7 @@ int expand_upwards(struct vm_area_struct *vma, unsigned long address)
 			if (!error) {
 				/*
 				 * vma_gap_update() doesn't support concurrent
-				 * updates, but we only hold a shared mmap_sem
+				 * updates, but we only hold a shared mmap_lock
 				 * lock here, so we need to protect against
 				 * concurrent vma expansions.
 				 * anon_vma_lock_write() doesn't help here, as
@@ -2451,7 +2451,7 @@ int expand_downwards(struct vm_area_struct *vma,
 
 	/*
 	 * vma->vm_start/vm_end cannot change under us because the caller
-	 * is required to hold the mmap_sem in read mode.  We need the
+	 * is required to hold the mmap_lock in read mode.  We need the
 	 * anon_vma lock to serialize against concurrent expand_stacks.
 	 */
 	anon_vma_lock_write(vma->anon_vma);
@@ -2469,7 +2469,7 @@ int expand_downwards(struct vm_area_struct *vma,
 			if (!error) {
 				/*
 				 * vma_gap_update() doesn't support concurrent
-				 * updates, but we only hold a shared mmap_sem
+				 * updates, but we only hold a shared mmap_lock
 				 * lock here, so we need to protect against
 				 * concurrent vma expansions.
 				 * anon_vma_lock_write() doesn't help here, as
@@ -2855,7 +2855,7 @@ static int __vm_munmap(unsigned long start, size_t len, bool downgrade)
 
 	ret = __do_munmap(mm, start, len, &uf, downgrade);
 	/*
-	 * Returning 1 indicates mmap_sem is downgraded.
+	 * Returning 1 indicates mmap_lock is downgraded.
 	 * But 1 is not legal return value of vm_munmap() and munmap(), reset
 	 * it to 0 before return.
 	 */
@@ -3107,12 +3107,12 @@ void exit_mmap(struct mm_struct *mm)
 		/*
 		 * Manually reap the mm to free as much memory as possible.
 		 * Then, as the oom reaper does, set MMF_OOM_SKIP to disregard
-		 * this mm from further consideration.  Taking mm->mmap_sem for
+		 * this mm from further consideration.  Taking mm->mmap_lock for
 		 * write after setting MMF_OOM_SKIP will guarantee that the oom
-		 * reaper will not run on this mm again after mmap_sem is
+		 * reaper will not run on this mm again after mmap_lock is
 		 * dropped.
 		 *
-		 * Nothing can be holding mm->mmap_sem here and the above call
+		 * Nothing can be holding mm->mmap_lock here and the above call
 		 * to mmu_notifier_release(mm) ensures mmu notifier callbacks in
 		 * __oom_reap_task_mm() will not block.
 		 *
@@ -3437,7 +3437,7 @@ bool vma_is_special_mapping(const struct vm_area_struct *vma,
 }
 
 /*
- * Called with mm->mmap_sem held for writing.
+ * Called with mm->mmap_lock held for writing.
  * Insert a new vma covering the given region, with the given flags.
  * Its pages are supplied by the given array of struct page *.
  * The array can be shorter than len >> PAGE_SHIFT if it's null-terminated.
@@ -3513,11 +3513,11 @@ static void vm_lock_mapping(struct mm_struct *mm, struct address_space *mapping)
  * operations that could ever happen on a certain mm. This includes
  * vmtruncate, try_to_unmap, and all page faults.
  *
- * The caller must take the mmap_sem in write mode before calling
+ * The caller must take the mmap_lock in write mode before calling
  * mm_take_all_locks(). The caller isn't allowed to release the
- * mmap_sem until mm_drop_all_locks() returns.
+ * mmap_lock until mm_drop_all_locks() returns.
  *
- * mmap_sem in write mode is required in order to block all operations
+ * mmap_lock in write mode is required in order to block all operations
  * that could modify pagetables and free pages without need of
  * altering the vma layout. It's also needed in write mode to avoid new
  * anon_vmas to be associated with existing vmas.
@@ -3622,7 +3622,7 @@ static void vm_unlock_mapping(struct address_space *mapping)
 }
 
 /*
- * The mmap_sem cannot be released by the caller until
+ * The mmap_lock cannot be released by the caller until
  * mm_drop_all_locks() returns.
  */
 void mm_drop_all_locks(struct mm_struct *mm)