AUDIT: Add helper functions to allocate and free audit_buffers.

Signed-off-by: Chris Wright <chrisw@osdl.org>
Signed-off-by: David Woodhouse <dwmw2@infradead.org>

1 files changed, 38 insertions, 23 deletions

diff --git a/kernel/audit.c b/kernel/audit.c
index 6f344b44d3d3..e5bdba3e3ae1 100644
--- a/kernel/audit.c
+++ b/kernel/audit.c
@@ -620,6 +620,42 @@ static int __init audit_enable(char *str)
 
 __setup("audit=", audit_enable);
 
+static void audit_buffer_free(struct audit_buffer *ab)
+{
+        unsigned long flags;
+
+        atomic_dec(&audit_backlog);
+        spin_lock_irqsave(&audit_freelist_lock, flags);
+        if (++audit_freelist_count > AUDIT_MAXFREE)
+                kfree(ab);
+        else
+                list_add(&ab->list, &audit_freelist);
+        spin_unlock_irqrestore(&audit_freelist_lock, flags);
+}
+
+static struct audit_buffer * audit_buffer_alloc(int gfp_mask)
+{
+        unsigned long flags;
+        struct audit_buffer *ab = NULL;
+
+        spin_lock_irqsave(&audit_freelist_lock, flags);
+        if (!list_empty(&audit_freelist)) {
+                ab = list_entry(audit_freelist.next,
+                                struct audit_buffer, list);
+                list_del(&ab->list);
+                --audit_freelist_count;
+        }
+        spin_unlock_irqrestore(&audit_freelist_lock, flags);
+
+        if (!ab) {
+                ab = kmalloc(sizeof(*ab), GFP_ATOMIC);
+                if (!ab)
+                        goto out;
+        }
+        atomic_inc(&audit_backlog);
+out:
+        return ab;
+}
 
 /* Obtain an audit buffer.  This routine does locking to obtain the
  * audit buffer, but then no locking is required for calls to
@@ -630,7 +666,6 @@ __setup("audit=", audit_enable);
 struct audit_buffer *audit_log_start(struct audit_context *ctx)
 {
         struct audit_buffer     *ab     = NULL;
-        unsigned long           flags;
         struct timespec         t;
         unsigned int            serial;
 
@@ -649,23 +684,12 @@ struct audit_buffer *audit_log_start(struct audit_context *ctx)
                 return NULL;
         }
 
-        spin_lock_irqsave(&audit_freelist_lock, flags);
-        if (!list_empty(&audit_freelist)) {
-                ab = list_entry(audit_freelist.next,
-                                struct audit_buffer, list);
-                list_del(&ab->list);
-                --audit_freelist_count;
-        }
-        spin_unlock_irqrestore(&audit_freelist_lock, flags);
-
-        if (!ab)
-                ab = kmalloc(sizeof(*ab), GFP_ATOMIC);
+        ab = audit_buffer_alloc(GFP_ATOMIC);
         if (!ab) {
                 audit_log_lost("out of memory in audit_log_start");
                 return NULL;
         }
 
-        atomic_inc(&audit_backlog);
         skb_queue_head_init(&ab->sklist);
 
         ab->ctx   = ctx;
@@ -824,8 +848,6 @@ static void audit_log_end_irq(struct audit_buffer *ab)
  * be called in an irq context. */
 static void audit_log_end_fast(struct audit_buffer *ab)
 {
-        unsigned long flags;
-
         BUG_ON(in_irq());
         if (!ab)
                 return;
@@ -836,14 +858,7 @@ static void audit_log_end_fast(struct audit_buffer *ab)
                 if (audit_log_drain(ab))
                         return;
         }
-
-        atomic_dec(&audit_backlog);
-        spin_lock_irqsave(&audit_freelist_lock, flags);
-        if (++audit_freelist_count > AUDIT_MAXFREE)
-                kfree(ab);
-        else
-                list_add(&ab->list, &audit_freelist);
-        spin_unlock_irqrestore(&audit_freelist_lock, flags);
+        audit_buffer_free(ab);
 }
 
 /* Send or queue the message in the audit buffer, depending on the