VMM Improvements.

    - Segment Manager
    - Base / Device Segments
    - Block for Base image.

Change-Id: Ic0c058e5c5b210ec1c48d30f6ed9f9837d74a3c8
Reviewed-on: http://gfw160.austin.ibm.com:8080/gerrit/193
Tested-by: Jenkins Server
Reviewed-by: MATTHEW S. BARTH <msbarth@us.ibm.com>

1 files changed, 92 insertions, 0 deletions

diff --git a/src/include/kernel/segmentmgr.H b/src/include/kernel/segmentmgr.H
new file mode 100644
index 000000000..7048fa365
--- /dev/null
+++ b/src/include/kernel/segmentmgr.H
@@ -0,0 +1,92 @@
+/** @file segmentmgr.H
+ *  Provides definition of the SegmentManager class.
+ */
+
+#ifndef __KERNEL_SEGMENTMGR_H
+#define __KERNEL_SEGMENTMGR_H
+
+#include <kernel/task.H>
+
+// Forward declaration.
+class Segment;
+
+/** @class SegmentManager
+ *  @brief Container of Segments.  Responsible for managing the SLB.
+ *
+ *  @note This class is not thread-safe on its own.  Expectation is that
+ *        the virtual memory manager will serialize internal operations.
+ */
+class SegmentManager
+{
+    public:
+        /** Segment Identifiers */
+        enum SegmentIds
+        {
+                /** Base Segment (0-1TB). */
+            BASE_SEGMENT_ID = 0,
+                /** Task Stack Segment (1-2TB). */
+            STACK_SEGMENT_ID = 1,
+                /** MMIO Space Segment (2-3TB). */
+            MMIO_SEGMENT_ID = 2,
+
+            MAX_SEGMENTS = 4
+        };
+
+        /**
+         * Constructor.  Initializes instance variables.
+         */
+        SegmentManager()
+            {
+                for(int i = 0; i < MAX_SEGMENTS; i++)
+                    iv_segments[i] = NULL;
+            };
+        /**
+         * Destructor.
+         * No action necessary.  Associated segments are owned externally,
+         * such as in Singletons.
+         */
+        ~SegmentManager() {};
+
+        /**
+         * @brief Responsible for directing page faults to the owning segment.
+         *
+         * @param[in] i_task - Task causing the page fault.
+         * @param[in] i_addr - Effective address accessed to cause fault.
+         *
+         * @return true - Page fault was successfully handled.
+         *
+         * If the page fault is not successfully handled the expectation is
+         * that the VMM will perform appropriate action, such as killing the
+         * task.
+         */
+        static bool handlePageFault(task_t* i_task, uint64_t i_addr);
+
+        /**
+         * @brief Adds a segment to the container.
+         *
+         * @param[in] i_segment - Segment object to associate to segment.
+         * @param[in] i_segId - Segment identifier (which TB) to associate.
+         *
+         * @note Ownership of the Segment object (for freeing memory) remains
+         *       with the callee.
+         */
+        static void addSegment(Segment* i_segment, size_t i_segId);
+
+        /**
+         * @brief Update SLB on this hardware thread with associated segments.
+         */
+        static void initSLB();
+
+    private:
+            /** See handlePageFault. */
+        bool _handlePageFault(task_t* i_task, uint64_t i_addr);
+            /** See addSegment. */
+        void _addSegment(Segment* i_segment, size_t i_segId);
+            /** See initSLB. */
+        void _initSLB();
+
+            /** Array of segment objects to associated segment IDs. */
+        Segment* iv_segments[MAX_SEGMENTS];
+};
+
+#endif