1 files changed, 96 insertions, 0 deletions
diff --git a/libipt/src/pt_block_cache.c b/libipt/src/pt_block_cache.c
new file mode 100644
index 000000000000..9c12a8ffb69d
--- /dev/null
+++ b/libipt/src/pt_block_cache.c
@@ -0,0 +1,96 @@
+/*
+ * Copyright (c) 2016-2019, Intel Corporation
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *  * Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *  * Neither the name of Intel Corporation nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "pt_block_cache.h"
+
+#include <stdlib.h>
+#include <string.h>
+
+
+struct pt_block_cache *pt_bcache_alloc(uint64_t nentries)
+{
+	struct pt_block_cache *bcache;
+	uint64_t size;
+
+	if (!nentries || (UINT32_MAX < nentries))
+		return NULL;
+
+	size = sizeof(*bcache) + (nentries * sizeof(struct pt_bcache_entry));
+	if (SIZE_MAX < size)
+		return NULL;
+
+	bcache = malloc((size_t) size);
+	if (!bcache)
+		return NULL;
+
+	memset(bcache, 0, (size_t) size);
+	bcache->nentries = (uint32_t) nentries;
+
+	return bcache;
+}
+
+void pt_bcache_free(struct pt_block_cache *bcache)
+{
+	free(bcache);
+}
+
+int pt_bcache_add(struct pt_block_cache *bcache, uint64_t index,
+		  struct pt_bcache_entry bce)
+{
+	if (!bcache)
+		return -pte_internal;
+
+	if (bcache->nentries <= index)
+		return -pte_internal;
+
+	/* We rely on guaranteed atomic operations as specified in section 8.1.1
+	 * in Volume 3A of the Intel(R) Software Developer's Manual at
+	 * http://www.intel.com/sdm.
+	 */
+	bcache->entry[(uint32_t) index] = bce;
+
+	return 0;
+}
+
+int pt_bcache_lookup(struct pt_bcache_entry *bce,
+		     const struct pt_block_cache *bcache, uint64_t index)
+{
+	if (!bce || !bcache)
+		return -pte_internal;
+
+	if (bcache->nentries <= index)
+		return -pte_internal;
+
+	/* We rely on guaranteed atomic operations as specified in section 8.1.1
+	 * in Volume 3A of the Intel(R) Software Developer's Manual at
+	 * http://www.intel.com/sdm.
+	 */
+	*bce = bcache->entry[(uint32_t) index];
+
+	return 0;
+}