ceph: use kref for ceph_msg

Signed-off-by: Sage Weil <sage@newdream.net>

3 files changed, 27 insertions, 35 deletions

diff --git a/fs/ceph/messenger.c b/fs/ceph/messenger.c
index bf762107b3d5..b0571b01b19f 100644
--- a/fs/ceph/messenger.c
+++ b/fs/ceph/messenger.c
@@ -1958,7 +1958,7 @@ struct ceph_msg *ceph_msg_new(int type, int front_len,
         m = kmalloc(sizeof(*m), GFP_NOFS);
         if (m == NULL)
                 goto out;
-        atomic_set(&m->nref, 1);
+        kref_init(&m->kref);
         INIT_LIST_HEAD(&m->list_head);
 
         m->hdr.type = cpu_to_le16(type);
@@ -2070,34 +2070,23 @@ void ceph_msg_kfree(struct ceph_msg *m)
 /*
  * Drop a msg ref.  Destroy as needed.
  */
-void ceph_msg_put(struct ceph_msg *m)
-{
-        dout("ceph_msg_put %p %d -> %d\n", m, atomic_read(&m->nref),
-             atomic_read(&m->nref)-1);
-        if (atomic_read(&m->nref) <= 0) {
-                pr_err("bad ceph_msg_put on %p %llu %d=%s %d+%d\n",
-                       m, le64_to_cpu(m->hdr.seq),
-                       le16_to_cpu(m->hdr.type),
-                       ceph_msg_type_name(le16_to_cpu(m->hdr.type)),
-                       le32_to_cpu(m->hdr.front_len),
-                       le32_to_cpu(m->hdr.data_len));
-                WARN_ON(1);
-        }
-        if (atomic_dec_and_test(&m->nref)) {
-                dout("ceph_msg_put last one on %p\n", m);
-                WARN_ON(!list_empty(&m->list_head));
-
-                /* drop middle, data, if any */
-                if (m->middle) {
-                        ceph_buffer_put(m->middle);
-                        m->middle = NULL;
-                }
-                m->nr_pages = 0;
-                m->pages = NULL;
+void ceph_msg_last_put(struct kref *kref)
+{
+        struct ceph_msg *m = container_of(kref, struct ceph_msg, kref);
 
-                if (m->pool)
-                        ceph_msgpool_put(m->pool, m);
-                else
-                        ceph_msg_kfree(m);
+        dout("ceph_msg_put last one on %p\n", m);
+        WARN_ON(!list_empty(&m->list_head));
+
+        /* drop middle, data, if any */
+        if (m->middle) {
+                ceph_buffer_put(m->middle);
+                m->middle = NULL;
         }
+        m->nr_pages = 0;
+        m->pages = NULL;
+
+        if (m->pool)
+                ceph_msgpool_put(m->pool, m);
+        else
+                ceph_msg_kfree(m);
 }
diff --git a/fs/ceph/messenger.h b/fs/ceph/messenger.h
index f9c9f6487302..981b7c08ad82 100644
--- a/fs/ceph/messenger.h
+++ b/fs/ceph/messenger.h
@@ -1,6 +1,7 @@
 #ifndef __FS_CEPH_MESSENGER_H
 #define __FS_CEPH_MESSENGER_H
 
+#include <linux/kref.h>
 #include <linux/mutex.h>
 #include <linux/net.h>
 #include <linux/radix-tree.h>
@@ -85,7 +86,7 @@ struct ceph_msg {
         struct page **pages;            /* data payload.  NOT OWNER. */
         unsigned nr_pages;              /* size of page array */
         struct list_head list_head;
-        atomic_t nref;
+        struct kref kref;
         bool front_is_vmalloc;
         bool more_to_follow;
         int front_max;
@@ -243,11 +244,13 @@ extern int ceph_alloc_middle(struct ceph_connection *con, struct ceph_msg *msg);
 
 static inline struct ceph_msg *ceph_msg_get(struct ceph_msg *msg)
 {
-        dout("ceph_msg_get %p %d -> %d\n", msg, atomic_read(&msg->nref),
-             atomic_read(&msg->nref)+1);
-        atomic_inc(&msg->nref);
+        kref_get(&msg->kref);
         return msg;
 }
-extern void ceph_msg_put(struct ceph_msg *msg);
+extern void ceph_msg_last_put(struct kref *kref);
+static inline void ceph_msg_put(struct ceph_msg *msg)
+{
+        kref_put(&msg->kref, ceph_msg_last_put);
+}
 
 #endif
diff --git a/fs/ceph/msgpool.c b/fs/ceph/msgpool.c
index 7599b3382076..ad5482c0267b 100644
--- a/fs/ceph/msgpool.c
+++ b/fs/ceph/msgpool.c
@@ -165,7 +165,7 @@ void ceph_msgpool_put(struct ceph_msgpool *pool, struct ceph_msg *msg)
 {
         spin_lock(&pool->lock);
         if (pool->num < pool->min) {
-                ceph_msg_get(msg);   /* retake a single ref */
+                kref_set(&msg->kref, 1);  /* retake a single ref */
                 list_add(&msg->list_head, &pool->msgs);
                 pool->num++;
                 dout("msgpool_put %p reclaim %p, now %d/%d\n", pool, msg,