int sizeInPages; // size of memory region in pages
};
+/** ReturnPageAlignedAddress returns a page aligned address for the
+ * address being added as a side effect the numBytes are also changed.
+ */
+static void * ReturnPageAlignedAddress(void *addr)
+{
+ return (void *)(((uintptr_t)addr) & ~(PAGESIZE - 1));
+}
+
/* Primary struct for snapshotting system */
struct mprot_snapshotter {
+ mprot_snapshotter(unsigned int numbackingpages, unsigned int numsnapshots, unsigned int nummemoryregions);
+
struct MemoryRegion *regionsToSnapShot; //This pointer references an array of memory regions to snapshot
snapshot_page_t *backingStore; //This pointer references an array of snapshotpage's that form the backing store
void *backingStoreBasePtr; //This pointer references an array of snapshotpage's that form the backing store
unsigned int maxRegions; //Stores the max number of memory regions we support
unsigned int maxBackingPages; //Stores the total number of backing pages
unsigned int maxSnapShots; //Stores the total number of snapshots we allow
+
+ MEMALLOC
};
static struct mprot_snapshotter *mprot_snap = NULL;
-/** ReturnPageAlignedAddress returns a page aligned address for the
- * address being added as a side effect the numBytes are also changed.
- */
-static void * ReturnPageAlignedAddress(void *addr)
-{
- return (void *)(((uintptr_t)addr) & ~(PAGESIZE - 1));
-}
-
-/** The initSnapShotRecord method initialized the snapshotting data
- * structures for the mprotect based snapshot.
- */
-static void initSnapShotRecord(unsigned int numbackingpages, unsigned int numsnapshots, unsigned int nummemoryregions)
+mprot_snapshotter::mprot_snapshotter(unsigned int backing_pages, unsigned int snapshots, unsigned int regions) :
+ lastSnapShot(0),
+ lastBackingPage(0),
+ lastRegion(0),
+ maxRegions(regions),
+ maxBackingPages(backing_pages),
+ maxSnapShots(snapshots)
{
- mprot_snap = (struct mprot_snapshotter *)model_malloc(sizeof(struct mprot_snapshotter));
- mprot_snap->regionsToSnapShot = (struct MemoryRegion *)model_malloc(sizeof(struct MemoryRegion) * nummemoryregions);
- mprot_snap->backingStoreBasePtr = (void *)model_malloc(sizeof(snapshot_page_t) * (numbackingpages + 1));
+ regionsToSnapShot = (struct MemoryRegion *)model_malloc(sizeof(struct MemoryRegion) * regions);
+ backingStoreBasePtr = (void *)model_malloc(sizeof(snapshot_page_t) * (backing_pages + 1));
//Page align the backingstorepages
- mprot_snap->backingStore = (snapshot_page_t *)PageAlignAddressUpward(mprot_snap->backingStoreBasePtr);
- mprot_snap->backingRecords = (struct BackingPageRecord *)model_malloc(sizeof(struct BackingPageRecord) * numbackingpages);
- mprot_snap->snapShots = (struct SnapShotRecord *)model_malloc(sizeof(struct SnapShotRecord) * numsnapshots);
- mprot_snap->lastSnapShot = 0;
- mprot_snap->lastBackingPage = 0;
- mprot_snap->lastRegion = 0;
- mprot_snap->maxRegions = nummemoryregions;
- mprot_snap->maxBackingPages = numbackingpages;
- mprot_snap->maxSnapShots = numsnapshots;
+ backingStore = (snapshot_page_t *)PageAlignAddressUpward(backingStoreBasePtr);
+ backingRecords = (struct BackingPageRecord *)model_malloc(sizeof(struct BackingPageRecord) * backing_pages);
+ snapShots = (struct SnapShotRecord *)model_malloc(sizeof(struct SnapShotRecord) * snapshots);
}
/** HandlePF is the page fault handler for mprotect based snapshotting
exit(EXIT_FAILURE);
}
- initSnapShotRecord(numbackingpages, numsnapshots, nummemoryregions);
+ mprot_snap = new mprot_snapshotter(numbackingpages, numsnapshots, nummemoryregions);
// EVIL HACK: We need to make sure that calls into the HandlePF method don't cause dynamic links
// The problem is that we end up protecting state in the dynamic linker...