From 230376d285b38f5b83882ebdd2e0d0570431dd09 Mon Sep 17 00:00:00 2001 From: Alexander Bulekov Date: Mon, 15 Mar 2021 10:05:10 -0400 Subject: memory: add a sparse memory device for fuzzing For testing, it can be useful to simulate an enormous amount of memory (e.g. 2^64 RAM). This adds an MMIO device that acts as sparse memory. When something writes a nonzero value to a sparse-mem address, we allocate a block of memory. For now, since the only user of this device is the fuzzer, we do not track and free zeroed blocks. The device has a very low priority (so it can be mapped beneath actual RAM, and virtual device MMIO regions). Signed-off-by: Alexander Bulekov Reviewed-by: Darren Kenny Signed-off-by: Paolo Bonzini --- include/hw/mem/sparse-mem.h | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) create mode 100644 include/hw/mem/sparse-mem.h (limited to 'include') diff --git a/include/hw/mem/sparse-mem.h b/include/hw/mem/sparse-mem.h new file mode 100644 index 0000000000..f9863b154b --- /dev/null +++ b/include/hw/mem/sparse-mem.h @@ -0,0 +1,19 @@ +/* + * A sparse memory device. Useful for fuzzing + * + * Copyright Red Hat Inc., 2021 + * + * Authors: + * Alexander Bulekov + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + */ + +#ifndef SPARSE_MEM_H +#define SPARSE_MEM_H +#define TYPE_SPARSE_MEM "sparse-mem" + +MemoryRegion *sparse_mem_init(uint64_t addr, uint64_t length); + +#endif -- cgit v1.2.3-55-g7522