mbuf: fix cloning with private mbuf data

[dpdk.git] / lib / librte_mbuf / rte_mbuf.h

diff --git a/lib/librte_mbuf/rte_mbuf.h b/lib/librte_mbuf/rte_mbuf.h
index 42db8e3..17d39ae 100644 (file)
--- a/lib/librte_mbuf/rte_mbuf.h
+++ b/lib/librte_mbuf/rte_mbuf.h
@@ -318,18 +318,49 @@ struct rte_mbuf {
                        /* uint64_t unused:8; */
                };
        };
+
+       /** Size of the application private data. In case of an indirect
+        * mbuf, it stores the direct mbuf private data size. */
+       uint16_t priv_size;
 } __rte_cache_aligned;
 
+static inline uint16_t rte_pktmbuf_priv_size(struct rte_mempool *mp);
+
 /**
- * Given the buf_addr returns the pointer to corresponding mbuf.
+ * Return the mbuf owning the data buffer address of an indirect mbuf.
+ *
+ * @param mi
+ *   The pointer to the indirect mbuf.
+ * @return
+ *   The address of the direct mbuf corresponding to buffer_addr.
  */
-#define RTE_MBUF_FROM_BADDR(ba)     (((struct rte_mbuf *)(ba)) - 1)
+static inline struct rte_mbuf *
+rte_mbuf_from_indirect(struct rte_mbuf *mi)
+{
+       struct rte_mbuf *md;
+
+       /* mi->buf_addr and mi->priv_size correspond to buffer and
+        * private size of the direct mbuf */
+       md = (struct rte_mbuf *)((char *)mi->buf_addr - sizeof(*mi) -
+               mi->priv_size);
+       return md;
+}
 
 /**
- * Given the pointer to mbuf returns an address where it's  buf_addr
- * should point to.
+ * Return the buffer address embedded in the given mbuf.
+ *
+ * @param md
+ *   The pointer to the mbuf.
+ * @return
+ *   The address of the data buffer owned by the mbuf.
  */
-#define RTE_MBUF_TO_BADDR(mb)       (((struct rte_mbuf *)(mb)) + 1)
+static inline char *
+rte_mbuf_to_baddr(struct rte_mbuf *md)
+{
+       char *buffer_addr;
+       buffer_addr = (char *)md + sizeof(*md) + rte_pktmbuf_priv_size(md->pool);
+       return buffer_addr;
+}
 
 /**
  * Returns TRUE if given mbuf is indirect, or FALSE otherwise.
@@ -771,6 +802,7 @@ static inline struct rte_mbuf *rte_pktmbuf_alloc(struct rte_mempool *mp)
 
 /**
  * Attach packet mbuf to another packet mbuf.
+ *
  * After attachment we refer the mbuf we attached as 'indirect',
  * while mbuf we attached to as 'direct'.
  * Right now, not supported:
@@ -784,7 +816,6 @@ static inline struct rte_mbuf *rte_pktmbuf_alloc(struct rte_mempool *mp)
  * @param md
  *   The direct packet mbuf.
  */
-
 static inline void rte_pktmbuf_attach(struct rte_mbuf *mi, struct rte_mbuf *md)
 {
        RTE_MBUF_ASSERT(RTE_MBUF_DIRECT(md) &&
@@ -795,6 +826,7 @@ static inline void rte_pktmbuf_attach(struct rte_mbuf *mi, struct rte_mbuf *md)
        mi->buf_physaddr = md->buf_physaddr;
        mi->buf_addr = md->buf_addr;
        mi->buf_len = md->buf_len;
+       mi->priv_size = md->priv_size;
 
        mi->next = md->next;
        mi->data_off = md->data_off;
@@ -815,7 +847,8 @@ static inline void rte_pktmbuf_attach(struct rte_mbuf *mi, struct rte_mbuf *md)
 }
 
 /**
- * Detach an indirect packet mbuf -
+ * Detach an indirect packet mbuf.
+ *
  *  - restore original mbuf address and length values.
  *  - reset pktmbuf data and data_len to their default values.
  *  All other fields of the given packet mbuf will be left intact.
@@ -823,22 +856,21 @@ static inline void rte_pktmbuf_attach(struct rte_mbuf *mi, struct rte_mbuf *md)
  * @param m
  *   The indirect attached packet mbuf.
  */
-
 static inline void rte_pktmbuf_detach(struct rte_mbuf *m)
 {
-       const struct rte_mempool *mp = m->pool;
-       void *buf = RTE_MBUF_TO_BADDR(m);
-       uint32_t buf_len = mp->elt_size - sizeof(*m);
-       m->buf_physaddr = rte_mempool_virt2phy(mp, m) + sizeof (*m);
+       struct rte_mempool *mp = m->pool;
+       uint32_t mbuf_size, buf_len, priv_size;
 
-       m->buf_addr = buf;
-       m->buf_len = (uint16_t)buf_len;
-
-       m->data_off = (RTE_PKTMBUF_HEADROOM <= m->buf_len) ?
-                       RTE_PKTMBUF_HEADROOM : m->buf_len;
+       priv_size = rte_pktmbuf_priv_size(mp);
+       mbuf_size = sizeof(struct rte_mbuf) + priv_size;
+       buf_len = rte_pktmbuf_data_room_size(mp);
 
+       m->priv_size = priv_size;
+       m->buf_addr = (char *)m + mbuf_size;
+       m->buf_physaddr = rte_mempool_virt2phy(mp, m) + mbuf_size;
+       m->buf_len = (uint16_t)buf_len;
+       m->data_off = RTE_MIN(RTE_PKTMBUF_HEADROOM, (uint16_t)m->buf_len);
        m->data_len = 0;
-
        m->ol_flags = 0;
 }
 
@@ -867,7 +899,7 @@ __rte_pktmbuf_prefree_seg(struct rte_mbuf *m)
                 *  - free attached mbuf segment
                 */
                if (RTE_MBUF_INDIRECT(m)) {
-                       struct rte_mbuf *md = RTE_MBUF_FROM_BADDR(m->buf_addr);
+                       struct rte_mbuf *md = rte_mbuf_from_indirect(m);
                        rte_pktmbuf_detach(m);
                        if (rte_mbuf_refcnt_update(md, -1) == 0)
                                __rte_mbuf_raw_free(md);