[PATCH 1/2] proc: Use IS_ERR_OR_NULL() helper

[Amerigo Wang <amwang@redhat.com>]

Use IS_ERR_OR_NULL() helper

Signed-off-by: Amerigo Wang <amwang@redhat.com>
---
 fs/proc/task_mmu.c   |   10 ++++++----
 fs/proc/task_nommu.c |    2 +-
 2 files changed, 7 insertions(+), 5 deletions(-)

diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index 2e7addf..3c06570 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -124,7 +124,7 @@ static void *m_start(struct seq_file *m, loff_t *pos)
 		return ERR_PTR(-ESRCH);
 
 	mm = mm_for_maps(priv->task);
-	if (!mm || IS_ERR(mm))
+	if (IS_ERR_OR_NULL(mm))
 		return mm;
 	down_read(&mm->mmap_sem);
 
@@ -182,7 +182,7 @@ static void m_stop(struct seq_file *m, void *v)
 	struct proc_maps_private *priv = m->private;
 	struct vm_area_struct *vma = v;
 
-	if (!IS_ERR(vma))
+	if (!IS_ERR_OR_NULL(vma))
 		vma_stop(priv, vma);
 	if (priv->task)
 		put_task_struct(priv->task);
@@ -768,9 +768,11 @@ static ssize_t pagemap_read(struct file *file, char __user *buf,
 		goto out;
 
 	mm = mm_for_maps(task);
-	ret = PTR_ERR(mm);
-	if (!mm || IS_ERR(mm))
+	if (IS_ERR_OR_NULL(mm)) {
+		if (mm)
+			ret = PTR_ERR(mm);
 		goto out_task;
+	}
 
 	ret = -EINVAL;
 	/* file position must be aligned */
diff --git a/fs/proc/task_nommu.c b/fs/proc/task_nommu.c
index 980de54..35e8b2a 100644
--- a/fs/proc/task_nommu.c
+++ b/fs/proc/task_nommu.c
@@ -202,7 +202,7 @@ static void *m_start(struct seq_file *m, loff_t *pos)
 		return ERR_PTR(-ESRCH);
 
 	mm = mm_for_maps(priv->task);
-	if (!mm || IS_ERR(mm)) {
+	if (IS_ERR_OR_NULL(mm)) {
 		put_task_struct(priv->task);
 		priv->task = NULL;
 		return mm;
-- 
1.7.4