aio: fix rcu sparse warnings introduced by ioctx table lookup patch

Sseveral sparse warnings were caused by missing rcu_dereference() annotations
for dereferencing mm->ioctx_table.  Thankfully, none of those were actual bugs
as the deref was protected by a spin lock in all instances.

Signed-off-by: Benjamin LaHaise <bcrl@kvack.org>
Reported-by: Fengguang Wu <fengguang.wu@intel.com>

1 files changed, 3 insertions, 3 deletions

diff --git a/fs/aio.c b/fs/aio.c
index d0defcb0a493..6e267553604c 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -470,7 +470,7 @@ static int ioctx_add_table(struct kioctx *ctx, struct mm_struct *mm)
         struct aio_ring *ring;
 
         spin_lock(&mm->ioctx_lock);
-        table = mm->ioctx_table;
+        table = rcu_dereference(mm->ioctx_table);
 
         while (1) {
                 if (table)
@@ -498,7 +498,7 @@ static int ioctx_add_table(struct kioctx *ctx, struct mm_struct *mm)
                 table->nr = new_nr;
 
                 spin_lock(&mm->ioctx_lock);
-                old = mm->ioctx_table;
+                old = rcu_dereference(mm->ioctx_table);
 
                 if (!old) {
                         rcu_assign_pointer(mm->ioctx_table, table);
@@ -622,7 +622,7 @@ static void kill_ioctx(struct mm_struct *mm, struct kioctx *ctx)
                 struct kioctx_table *table;
 
                 spin_lock(&mm->ioctx_lock);
-                table = mm->ioctx_table;
+                table = rcu_dereference(mm->ioctx_table);
 
                 WARN_ON(ctx != table->table[ctx->id]);
                 table->table[ctx->id] = NULL;