mlx5: Keep polling to reclaim pages while any returned

[mirror_ubuntu-bionic-kernel.git] / fs / aio.c

diff --git a/fs/aio.c b/fs/aio.c
index f4a27af6c9ac38daa54ee8bc0700d0d98bc32216..6b868f0e0c4c019c3b68712ca230deb979711a98 100644 (file)
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -479,6 +479,7 @@ static int ioctx_add_table(struct kioctx *ctx, struct mm_struct *mm)
        struct aio_ring *ring;
 
        spin_lock(&mm->ioctx_lock);
+       rcu_read_lock();
        table = rcu_dereference(mm->ioctx_table);
 
        while (1) {
@@ -487,6 +488,7 @@ static int ioctx_add_table(struct kioctx *ctx, struct mm_struct *mm)
                                if (!table->table[i]) {
                                        ctx->id = i;
                                        table->table[i] = ctx;
+                                       rcu_read_unlock();
                                        spin_unlock(&mm->ioctx_lock);
 
                                        ring = kmap_atomic(ctx->ring_pages[0]);
@@ -497,6 +499,7 @@ static int ioctx_add_table(struct kioctx *ctx, struct mm_struct *mm)
 
                new_nr = (table ? table->nr : 1) * 4;
 
+               rcu_read_unlock();
                spin_unlock(&mm->ioctx_lock);
 
                table = kzalloc(sizeof(*table) + sizeof(struct kioctx *) *
@@ -507,6 +510,7 @@ static int ioctx_add_table(struct kioctx *ctx, struct mm_struct *mm)
                table->nr = new_nr;
 
                spin_lock(&mm->ioctx_lock);
+               rcu_read_lock();
                old = rcu_dereference(mm->ioctx_table);
 
                if (!old) {
@@ -631,10 +635,12 @@ static void kill_ioctx(struct mm_struct *mm, struct kioctx *ctx)
                struct kioctx_table *table;
 
                spin_lock(&mm->ioctx_lock);
+               rcu_read_lock();
                table = rcu_dereference(mm->ioctx_table);
 
                WARN_ON(ctx != table->table[ctx->id]);
                table->table[ctx->id] = NULL;
+               rcu_read_unlock();
                spin_unlock(&mm->ioctx_lock);
 
                /* percpu_ref_kill() will do the necessary call_rcu() */