X-Git-Url: https://git.saurik.com/apple/xnu.git/blobdiff_plain/43866e378188c25dd1e2208016ab3cbeb086ae6c..008676633c2ad2c325837c2b64915f7ded690a8f:/iokit/Kernel/IOMemoryCursor.cpp

diff --git a/iokit/Kernel/IOMemoryCursor.cpp b/iokit/Kernel/IOMemoryCursor.cpp
index 1c4152321..99999991d 100644
--- a/iokit/Kernel/IOMemoryCursor.cpp
+++ b/iokit/Kernel/IOMemoryCursor.cpp
@@ -1,16 +1,19 @@
 /*
  * Copyright (c) 1998-2000 Apple Computer, Inc. All rights reserved.
  *
- * @APPLE_LICENSE_HEADER_START@
- * 
- * Copyright (c) 1999-2003 Apple Computer, Inc.  All Rights Reserved.
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
  * 
  * This file contains Original Code and/or Modifications of Original Code
  * as defined in and that are subject to the Apple Public Source License
  * Version 2.0 (the 'License'). You may not use this file except in
- * compliance with the License. Please obtain a copy of the License at
- * http://www.opensource.apple.com/apsl/ and read it before using this
- * file.
+ * compliance with the License. The rights granted to you under the License
+ * may not be used to create, or enable the creation or redistribution of,
+ * unlawful or unlicensed copies of an Apple operating system, or to
+ * circumvent, violate, or enable the circumvention or violation of, any
+ * terms of an Apple operating system software license agreement.
+ * 
+ * Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this file.
  * 
  * The Original Code and all software distributed under the License are
  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
@@ -20,7 +23,7 @@
  * Please see the License for the specific language governing rights and
  * limitations under the License.
  * 
- * @APPLE_LICENSE_HEADER_END@
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  */
 /* IOMemoryCursor.cpp created by wgulland on 1999-3-02 */
 
@@ -64,6 +67,18 @@ IOMemoryCursor::initWithSpecification(SegmentFunction  inSegFunc,
                                       IOPhysicalLength inMaxTransferSize,
                                       IOPhysicalLength inAlignment)
 {
+// @@@ gvdl: Remove me
+#if 1
+static UInt sMaxDBDMASegment;
+if (!sMaxDBDMASegment) {
+    sMaxDBDMASegment = (UInt) -1;
+    if (PE_parse_boot_argn("mseg", &sMaxDBDMASegment, sizeof (sMaxDBDMASegment)))
+        IOLog("Setting MaxDBDMASegment to %d\n", sMaxDBDMASegment);
+}
+
+if (inMaxSegmentSize > sMaxDBDMASegment) inMaxSegmentSize = sMaxDBDMASegment;
+#endif
+
     if (!super::init())
         return false;
 
@@ -86,7 +101,7 @@ IOMemoryCursor::initWithSpecification(SegmentFunction  inSegFunc,
 
 UInt32 
 IOMemoryCursor::genPhysicalSegments(IOMemoryDescriptor *inDescriptor,
-                                    IOPhysicalLength	fromPosition,
+                                    IOByteCount		fromPosition,
                                     void *		inSegments,
                                     UInt32		inMaxSegments,
                                     UInt32		inMaxTransferSize,
@@ -107,22 +122,66 @@ IOMemoryCursor::genPhysicalSegments(IOMemoryDescriptor *inDescriptor,
      * If we finished cleanly return number of segments found
      * and update the position in the descriptor.
      */
+    PhysicalSegment curSeg = { 0, 0 };
     UInt curSegIndex = 0;
     UInt curTransferSize = 0;
-    PhysicalSegment seg;
+    IOByteCount inDescriptorLength = inDescriptor->getLength();
+    PhysicalSegment seg = { 0, 0 };
 
-    while ((curSegIndex < inMaxSegments)
-    &&  (curTransferSize < inMaxTransferSize)
-    &&  (seg.location = inDescriptor->getPhysicalSegment(
-                            fromPosition + curTransferSize, &seg.length)))
+    while ((seg.location) || (fromPosition < inDescriptorLength)) 
     {
-        assert(seg.length);
-        seg.length = min(inMaxTransferSize-curTransferSize,
-                         (min(seg.length, maxSegmentSize)));
-        (*outSeg)(seg, inSegments, curSegIndex++);
-        curTransferSize += seg.length;
+        if (!seg.location)
+        {
+            seg.location = inDescriptor->getPhysicalSegment(
+                               fromPosition, (IOByteCount*)&seg.length);
+            assert(seg.location);
+            assert(seg.length);
+            fromPosition += seg.length;
+        }
+
+        if (!curSeg.location)
+        {
+            curTransferSize += seg.length;
+            curSeg = seg;
+            seg.location = 0;
+        }
+        else if ((curSeg.location + curSeg.length == seg.location))
+        {
+            curTransferSize += seg.length;
+            curSeg.length += seg.length;
+            seg.location = 0;
+        }
+
+        if (!seg.location)
+        {
+            if ((curSeg.length > maxSegmentSize))
+            {
+                seg.location = curSeg.location + maxSegmentSize;
+                seg.length = curSeg.length - maxSegmentSize;
+                curTransferSize -= seg.length;
+                curSeg.length -= seg.length;
+            }
+
+            if ((curTransferSize >= inMaxTransferSize))
+            {
+                curSeg.length -= curTransferSize - inMaxTransferSize;
+                curTransferSize = inMaxTransferSize;
+                break;
+            }
+        }
+
+        if (seg.location)
+        {
+            if ((curSegIndex + 1 == inMaxSegments))
+                break;
+            (*outSeg)(curSeg, inSegments, curSegIndex++);
+            curSeg.location = 0;
+        }
     }
 
+    if (curSeg.location)
+        (*outSeg)(curSeg, inSegments, curSegIndex++);
+
     if (outTransferSize)
         *outTransferSize = curTransferSize;
 
@@ -266,66 +325,3 @@ IOLittleMemoryCursor::initWithSpecification(IOPhysicalLength inMaxSegmentSize,
                                         inMaxTransferSize,
                                         inAlignment);
 }
-
-/************************* class IODBDMAMemoryCursor *************************/
-
-#if defined(__ppc__)
-
-#include <IOKit/ppc/IODBDMA.h>
-
-#undef super
-#define super IOMemoryCursor
-OSDefineMetaClassAndStructors(IODBDMAMemoryCursor, IOMemoryCursor)
-
-void 
-IODBDMAMemoryCursor::outputSegment(PhysicalSegment inSegment,
-                                   void *	   inSegments,
-                                   UInt32	   inSegmentIndex)
-{
-    IODBDMADescriptor *segment;
-
-    segment = &((IODBDMADescriptor *) inSegments)[inSegmentIndex];
-
-    // Write location into address field
-    OSWriteSwapInt32((UInt32 *) segment, 4, inSegment.location);
-
-    // Write count into 1st two bytes of operation field.
-    // DO NOT touch rest of operation field as it should contain a STOP command.
-    OSWriteSwapInt16((UInt16 *) segment, 0, inSegment.length);
-}
-
-/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
-
-IODBDMAMemoryCursor *
-IODBDMAMemoryCursor::withSpecification(IOPhysicalLength inMaxSegmentSize,
-                                       IOPhysicalLength inMaxTransferSize,
-                                       IOPhysicalLength inAlignment)
-{
-    IODBDMAMemoryCursor *me = new IODBDMAMemoryCursor;
-
-    if (me && !me->initWithSpecification(inMaxSegmentSize,
-                                         inMaxTransferSize,
-                                         inAlignment))
-    {
-        me->release();
-        return 0;
-    }
-
-    return me;
-}
-
-/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
-
-bool
-IODBDMAMemoryCursor::initWithSpecification(IOPhysicalLength inMaxSegmentSize,
-                                           IOPhysicalLength inMaxTransferSize,
-                                           IOPhysicalLength inAlignment)
-{
-    return super::initWithSpecification(&IODBDMAMemoryCursor::outputSegment,
-                                        inMaxSegmentSize,
-                                        inMaxTransferSize,
-                                        inAlignment);
-}
-
-#endif /* defined(__ppc__) */
-