improvements to shared memory handling

+ Now each shared region is reference counter (technically each region
  is refernce counted, private regions just have a count of 1).
  Also, syscalls that touch the TLB get flushed, but should probably
  look into where else this flushing might be needed.

2 files changed, 9 insertions, 0 deletions

diff --git a/include/kmi/assert.h b/include/kmi/assert.h
index ecf5272..14e0679 100644
--- a/include/kmi/assert.h
+++ b/include/kmi/assert.h
@@ -18,6 +18,7 @@
  * Catastrophic assertions warn about the assertion and crash the kernel.
  */
 
+#include <kmi/power.h>
 #include <kmi/debug.h>
 #include <kmi/utils.h>
 
@@ -35,6 +36,7 @@
 		if (unlikely(!(x))) {                        \
 			error("assertion failed: " #x "\n"); \
 			while (1) {                          \
+				poweroff(SYS_COLD_REBOOT);   \
 			}                                    \
 		}                                            \
 	} while (0);
diff --git a/include/kmi/regions.h b/include/kmi/regions.h
index ebaa07a..5167d28 100644
--- a/include/kmi/regions.h
+++ b/include/kmi/regions.h
@@ -78,6 +78,8 @@ struct mem_region_root {
  * track of free and used regions, respectively. All regions are chained
  * together with a doubly linked list, so that the next region's start address
  * should be the current region's end address.
+ *
+ * Note that addresses are expressed in pages!
  */
 struct mem_region {
 	/** Sp-tree node slot. */
@@ -98,6 +100,11 @@ struct mem_region {
 	/** In shared regions, mark the other pid that shared the region. */
 	id_t pid;
 
+	union {
+		vm_t shaddr;
+		size_t refcount;
+	};
+
 	/** Memory region flags, both access as well as metadata. \see MR_USED,
 	 * MR_SHARED, MR_OWNED, MR_COW, MR_KEEP. */
 	vmflags_t flags;