memzone: clarify support for zero-length memzones

[dpdk.git] / lib / librte_eal / common / include / rte_memzone.h

diff --git a/lib/librte_eal/common/include/rte_memzone.h b/lib/librte_eal/common/include/rte_memzone.h
index e2630fd..ef370fa 100644 (file)
--- a/lib/librte_eal/common/include/rte_memzone.h
+++ b/lib/librte_eal/common/include/rte_memzone.h
@@ -68,7 +68,6 @@ struct rte_memzone {
        int32_t socket_id;                /**< NUMA socket ID. */
 
        uint32_t flags;                   /**< Characteristics of this memzone. */
-       uint32_t memseg_id;               /**< Memseg it belongs. */
 } __attribute__((__packed__));
 
 /**
@@ -78,6 +77,13 @@ struct rte_memzone {
  * correctly filled memzone descriptor. If the allocation cannot be
  * done, return NULL.
  *
+ * @note Reserving memzones with len set to 0 will only attempt to allocate
+ *   memzones from memory that is already available. It will not trigger any
+ *   new allocations.
+ *
+ * @note Reserving IOVA-contiguous memzones with len set to 0 is not currently
+ *   supported.
+ *
  * @param name
  *   The name of the memzone. If it already exists, the function will
  *   fail and return NULL.
@@ -131,6 +137,13 @@ const struct rte_memzone *rte_memzone_reserve(const char *name,
  * descriptor. If the allocation cannot be done or if the alignment
  * is not a power of 2, returns NULL.
  *
+ * @note Reserving memzones with len set to 0 will only attempt to allocate
+ *   memzones from memory that is already available. It will not trigger any
+ *   new allocations.
+ *
+ * @note Reserving IOVA-contiguous memzones with len set to 0 is not currently
+ *   supported.
+ *
  * @param name
  *   The name of the memzone. If it already exists, the function will
  *   fail and return NULL.
@@ -189,6 +202,13 @@ const struct rte_memzone *rte_memzone_reserve_aligned(const char *name,
  * boundary. That implies that requested length should be less or equal
  * then boundary.
  *
+ * @note Reserving memzones with len set to 0 will only attempt to allocate
+ *   memzones from memory that is already available. It will not trigger any
+ *   new allocations.
+ *
+ * @note Reserving IOVA-contiguous memzones with len set to 0 is not currently
+ *   supported.
+ *
  * @param name
  *   The name of the memzone. If it already exists, the function will
  *   fail and return NULL.