[PATCH v5 2/4] RISC-V: mm: Add tests for RISC-V mm

[Charlie Jenkins]

Add tests that enforce mmap hint address behavior. mmap should default
to sv48. mmap will provide an address at the highest address space that
can fit into the hint address, unless the hint address is less than sv39
and not 0, then it will return a sv39 address. In addition, ensure that
rlimit changes do not cause mmap to fail.

Signed-off-by: Charlie Jenkins <charlie at rivosinc.com>
---
 tools/testing/selftests/riscv/Makefile        |   2 +-
 tools/testing/selftests/riscv/mm/.gitignore   |   1 +
 tools/testing/selftests/riscv/mm/Makefile     |  21 +++
 .../selftests/riscv/mm/testcases/mmap.c       | 133 ++++++++++++++++++
 4 files changed, 156 insertions(+), 1 deletion(-)
 create mode 100644 tools/testing/selftests/riscv/mm/.gitignore
 create mode 100644 tools/testing/selftests/riscv/mm/Makefile
 create mode 100644 tools/testing/selftests/riscv/mm/testcases/mmap.c

diff --git a/tools/testing/selftests/riscv/Makefile b/tools/testing/selftests/riscv/Makefile
index 32a72902d045..0fee58f990ae 100644
--- a/tools/testing/selftests/riscv/Makefile
+++ b/tools/testing/selftests/riscv/Makefile
@@ -5,7 +5,7 @@
 ARCH ?= $(shell uname -m 2>/dev/null || echo not)
 
 ifneq (,$(filter $(ARCH),riscv))
-RISCV_SUBTARGETS ?= hwprobe
+RISCV_SUBTARGETS ?= hwprobe mm
 else
 RISCV_SUBTARGETS :=
 endif
diff --git a/tools/testing/selftests/riscv/mm/.gitignore b/tools/testing/selftests/riscv/mm/.gitignore
new file mode 100644
index 000000000000..9a6f303edcd3
--- /dev/null
+++ b/tools/testing/selftests/riscv/mm/.gitignore
@@ -0,0 +1 @@
+mmap
diff --git a/tools/testing/selftests/riscv/mm/Makefile b/tools/testing/selftests/riscv/mm/Makefile
new file mode 100644
index 000000000000..cf68e63e7495
--- /dev/null
+++ b/tools/testing/selftests/riscv/mm/Makefile
@@ -0,0 +1,21 @@
+# SPDX-License-Identifier: GPL-2.0
+# Originally tools/testing/selftests/arm64/signal
+
+# Additional include paths needed by kselftest.h and local headers
+CFLAGS += -D_GNU_SOURCE -std=gnu99 -I.
+
+SRCS := $(filter-out testcases/testcases.c,$(wildcard testcases/*.c))
+PROGS := $(patsubst %.c,%,$(SRCS))
+
+# Generated binaries to be installed by top KSFT script
+TEST_GEN_PROGS := $(notdir $(PROGS))
+
+# Get Kernel headers installed and use them.
+
+# Including KSFT lib.mk here will also mangle the TEST_GEN_PROGS list
+# to account for any OUTPUT target-dirs optionally provided by
+# the toplevel makefile
+include ../../lib.mk
+
+$(TEST_GEN_PROGS): $(PROGS)
+	cp $(PROGS) $(OUTPUT)/
diff --git a/tools/testing/selftests/riscv/mm/testcases/mmap.c b/tools/testing/selftests/riscv/mm/testcases/mmap.c
new file mode 100644
index 000000000000..d8e751f7b8c9
--- /dev/null
+++ b/tools/testing/selftests/riscv/mm/testcases/mmap.c
@@ -0,0 +1,133 @@
+// SPDX-License-Identifier: GPL-2.0-only
+#include <sys/mman.h>
+#include <sys/resource.h>
+#include <sys/time.h>
+
+#include "../../kselftest_harness.h"
+struct addresses {
+	int *no_hint;
+	int *on_37_addr;
+	int *on_38_addr;
+	int *on_46_addr;
+	int *on_47_addr;
+	int *on_55_addr;
+	int *on_56_addr;
+};
+
+void do_mmaps(struct addresses *mmap_addresses)
+{
+	// Place all of the hint addresses on the boundaries of mmap
+	// sv39, sv48, sv57
+	// User addresses end at 1<<38, 1<<47, 1<<56 respectively
+	void *on_37_bits = (void *)(1UL << 37);
+	void *on_38_bits = (void *)(1UL << 38);
+	void *on_46_bits = (void *)(1UL << 46);
+	void *on_47_bits = (void *)(1UL << 47);
+	void *on_55_bits = (void *)(1UL << 55);
+	void *on_56_bits = (void *)(1UL << 56);
+
+	int prot = PROT_READ | PROT_WRITE;
+	int flags = MAP_PRIVATE | MAP_ANONYMOUS;
+
+	mmap_addresses->no_hint =
+		mmap(NULL, 5 * sizeof(int), prot, flags, 0, 0);
+	mmap_addresses->on_37_addr =
+		mmap(on_37_bits, 5 * sizeof(int), prot, flags, 0, 0);
+	mmap_addresses->on_38_addr =
+		mmap(on_38_bits, 5 * sizeof(int), prot, flags, 0, 0);
+	mmap_addresses->on_46_addr =
+		mmap(on_46_bits, 5 * sizeof(int), prot, flags, 0, 0);
+	mmap_addresses->on_47_addr =
+		mmap(on_47_bits, 5 * sizeof(int), prot, flags, 0, 0);
+	mmap_addresses->on_55_addr =
+		mmap(on_55_bits, 5 * sizeof(int), prot, flags, 0, 0);
+	mmap_addresses->on_56_addr =
+		mmap(on_56_bits, 5 * sizeof(int), prot, flags, 0, 0);
+}
+
+TEST(default_rlimit)
+{
+// Only works on 64 bit
+#if __riscv_xlen == 64
+	struct addresses mmap_addresses;
+
+	do_mmaps(&mmap_addresses);
+
+	EXPECT_NE(mmap_addresses.no_hint, MAP_FAILED);
+	EXPECT_NE(mmap_addresses.on_37_addr, MAP_FAILED);
+	EXPECT_NE(mmap_addresses.on_38_addr, MAP_FAILED);
+	EXPECT_NE(mmap_addresses.on_46_addr, MAP_FAILED);
+	EXPECT_NE(mmap_addresses.on_47_addr, MAP_FAILED);
+	EXPECT_NE(mmap_addresses.on_55_addr, MAP_FAILED);
+	EXPECT_NE(mmap_addresses.on_56_addr, MAP_FAILED);
+
+	EXPECT_LT((unsigned long)mmap_addresses.no_hint, 1UL << 47);
+	EXPECT_LT((unsigned long)mmap_addresses.on_37_addr, 1UL << 38);
+	EXPECT_LT((unsigned long)mmap_addresses.on_38_addr, 1UL << 38);
+	EXPECT_LT((unsigned long)mmap_addresses.on_46_addr, 1UL << 38);
+	EXPECT_LT((unsigned long)mmap_addresses.on_47_addr, 1UL << 47);
+	EXPECT_LT((unsigned long)mmap_addresses.on_55_addr, 1UL << 47);
+	EXPECT_LT((unsigned long)mmap_addresses.on_56_addr, 1UL << 56);
+#endif
+}
+
+TEST(zero_rlimit)
+{
+// Only works on 64 bit
+#if __riscv_xlen == 64
+	struct addresses mmap_addresses;
+	struct rlimit rlim_new = { .rlim_cur = 0, .rlim_max = RLIM_INFINITY };
+
+	setrlimit(RLIMIT_STACK, &rlim_new);
+
+	do_mmaps(&mmap_addresses);
+
+	EXPECT_NE(mmap_addresses.no_hint, MAP_FAILED);
+	EXPECT_NE(mmap_addresses.on_37_addr, MAP_FAILED);
+	EXPECT_NE(mmap_addresses.on_38_addr, MAP_FAILED);
+	EXPECT_NE(mmap_addresses.on_46_addr, MAP_FAILED);
+	EXPECT_NE(mmap_addresses.on_47_addr, MAP_FAILED);
+	EXPECT_NE(mmap_addresses.on_55_addr, MAP_FAILED);
+	EXPECT_NE(mmap_addresses.on_56_addr, MAP_FAILED);
+
+	EXPECT_LT((unsigned long)mmap_addresses.no_hint, 1UL << 47);
+	EXPECT_LT((unsigned long)mmap_addresses.on_37_addr, 1UL << 38);
+	EXPECT_LT((unsigned long)mmap_addresses.on_38_addr, 1UL << 38);
+	EXPECT_LT((unsigned long)mmap_addresses.on_46_addr, 1UL << 38);
+	EXPECT_LT((unsigned long)mmap_addresses.on_47_addr, 1UL << 47);
+	EXPECT_LT((unsigned long)mmap_addresses.on_55_addr, 1UL << 47);
+	EXPECT_LT((unsigned long)mmap_addresses.on_56_addr, 1UL << 56);
+#endif
+}
+
+TEST(infinite_rlimit)
+{
+// Only works on 64 bit
+#if __riscv_xlen == 64
+	struct addresses mmap_addresses;
+	struct rlimit rlim_new = { .rlim_cur = RLIM_INFINITY,
+				   .rlim_max = RLIM_INFINITY };
+
+	setrlimit(RLIMIT_STACK, &rlim_new);
+
+	do_mmaps(&mmap_addresses);
+
+	EXPECT_NE(mmap_addresses.no_hint, MAP_FAILED);
+	EXPECT_NE(mmap_addresses.on_37_addr, MAP_FAILED);
+	EXPECT_NE(mmap_addresses.on_38_addr, MAP_FAILED);
+	EXPECT_NE(mmap_addresses.on_46_addr, MAP_FAILED);
+	EXPECT_NE(mmap_addresses.on_47_addr, MAP_FAILED);
+	EXPECT_NE(mmap_addresses.on_55_addr, MAP_FAILED);
+	EXPECT_NE(mmap_addresses.on_56_addr, MAP_FAILED);
+
+	EXPECT_LT((unsigned long)mmap_addresses.no_hint, 1UL << 47);
+	EXPECT_LT((unsigned long)mmap_addresses.on_37_addr, 1UL << 38);
+	EXPECT_LT((unsigned long)mmap_addresses.on_38_addr, 1UL << 38);
+	EXPECT_LT((unsigned long)mmap_addresses.on_46_addr, 1UL << 38);
+	EXPECT_LT((unsigned long)mmap_addresses.on_47_addr, 1UL << 47);
+	EXPECT_LT((unsigned long)mmap_addresses.on_55_addr, 1UL << 47);
+	EXPECT_LT((unsigned long)mmap_addresses.on_56_addr, 1UL << 56);
+#endif
+}
+
+TEST_HARNESS_MAIN
-- 
2.41.0