Changeset 99962 in vbox

Timestamp:

May 24, 2023 11:27:39 PM (18 months ago)

Author:

vboxsync

Message:

VBox/types.h,pdmnetifs.h: Replaced PDMDATASEG with RTSGSEG since the two structures are identical. This should make it easy to create a RTSGBUF for a PDMSCATTERGATHER buffer (just limit the operations to cbUsed bytes).

Location:

trunk/include/VBox

Files:

• types.h (modified) (1 diff)
• vmm/pdmnetifs.h (modified) (3 diffs)

trunk/include/VBox/types.h

@@ -1016 +1016 @@
 
 /**
- * Data transport buffer (scatter/gather)
- */
-typedef struct PDMDATASEG
-{
-    /** Length of buffer in entry. */
-    size_t  cbSeg;
-    /** Pointer to the start of the buffer. */
-    void   *pvSeg;
-} PDMDATASEG;
-/** Pointer to a data transport segment. */
-typedef PDMDATASEG *PPDMDATASEG;
-/** Pointer to a const data transport segment. */
-typedef PDMDATASEG const *PCPDMDATASEG;
-
-
-/**
  * Forms of generic segment offloading.
  */

trunk/include/VBox/vmm/pdmnetifs.h

@@ -41 +41 @@
 
 #include <VBox/types.h>
+#include <iprt/sg.h>
 
 
@@ -53 +54 @@
 /**
  * PDM scatter/gather buffer.
- *
+ *  
+ * @note    This is a little bit similar to the RTSGBUF structure in IPRT. 
+ *  
+ *          It is possible to reuse the PDMSCATTERGATHER::aSegs member here in a
+ *          RTSGBUF, but must always remember to specify
+ *          PDMSCATTERGATHER::cbUsed as the max length to any RTSgBufXxxx API
+ *          call, since the segments here will (normally) describe the full
+ *          PDMSCATTERGATHER::cbAvailable length.
+ *  
  * @todo Promote this to VBox/types.h, VBox/vmm/pdmcommon.h or some such place.
  */
@@ -73 +82 @@
      * This is set on alloc and not changed by the user. */
     size_t          cSegs;
-    /** Variable sized array of segments. */
-    PDMDATASEG      aSegs[1];
+    /** Variable sized array of segments.
+     * This describes the max allocated buffer length, consumers must limit
+     * operations to PDMSCATTERGATHER::cbUser. */ 
+    RTSGSEG         aSegs[1];
 } PDMSCATTERGATHER;
 /** Pointer to a PDM scatter/gather buffer. */