From 4e5ce33ceb3250f564656588da4d47f3eca7d2af Mon Sep 17 00:00:00 2001 From: Anshuman Khandual Date: Mon, 8 May 2017 16:00:19 -0700 Subject: [PATCH] selftests/vm: add a test for virtual address range mapping This verifies virtual address mapping below and above the 128TB range and makes sure that address returned are within the expected range depending upon the hint passed from the user space. Link: http://lkml.kernel.org/r/20170418095252.20533-1-khandual@linux.vnet.ibm.com Signed-off-by: Anshuman Khandual Cc: Michal Suchanek Cc: Aneesh Kumar K.V Cc: Shuah Khan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- tools/testing/selftests/vm/Makefile | 1 + tools/testing/selftests/vm/run_vmtests | 11 ++ .../selftests/vm/virtual_address_range.c | 122 ++++++++++++++++++ 3 files changed, 134 insertions(+) create mode 100644 tools/testing/selftests/vm/virtual_address_range.c diff --git a/tools/testing/selftests/vm/Makefile b/tools/testing/selftests/vm/Makefile index dba889004ea1..cbb29e41ef2b 100644 --- a/tools/testing/selftests/vm/Makefile +++ b/tools/testing/selftests/vm/Makefile @@ -16,6 +16,7 @@ TEST_GEN_FILES += thuge-gen TEST_GEN_FILES += transhuge-stress TEST_GEN_FILES += userfaultfd TEST_GEN_FILES += mlock-random-test +TEST_GEN_FILES += virtual_address_range TEST_PROGS := run_vmtests diff --git a/tools/testing/selftests/vm/run_vmtests b/tools/testing/selftests/vm/run_vmtests index 3214a6456d13..0640923ded7e 100755 --- a/tools/testing/selftests/vm/run_vmtests +++ b/tools/testing/selftests/vm/run_vmtests @@ -165,4 +165,15 @@ else echo "[PASS]" fi +echo "-----------------------------" +echo "running virtual_address_range" +echo "-----------------------------" +./virtual_address_range +if [ $? -ne 0 ]; then + echo "[FAIL]" + exitcode=1 +else + echo "[PASS]" +fi + exit $exitcode diff --git a/tools/testing/selftests/vm/virtual_address_range.c b/tools/testing/selftests/vm/virtual_address_range.c new file mode 100644 index 000000000000..3b02aa6eb9da --- /dev/null +++ b/tools/testing/selftests/vm/virtual_address_range.c @@ -0,0 +1,122 @@ +/* + * Copyright 2017, Anshuman Khandual, IBM Corp. + * Licensed under GPLv2. + * + * Works on architectures which support 128TB virtual + * address range and beyond. + */ +#include +#include +#include +#include +#include +#include +#include +#include + +/* + * Maximum address range mapped with a single mmap() + * call is little bit more than 16GB. Hence 16GB is + * chosen as the single chunk size for address space + * mapping. + */ +#define MAP_CHUNK_SIZE 17179869184UL /* 16GB */ + +/* + * Address space till 128TB is mapped without any hint + * and is enabled by default. Address space beyond 128TB + * till 512TB is obtained by passing hint address as the + * first argument into mmap() system call. + * + * The process heap address space is divided into two + * different areas one below 128TB and one above 128TB + * till it reaches 512TB. One with size 128TB and the + * other being 384TB. + */ +#define NR_CHUNKS_128TB 8192UL /* Number of 16GB chunks for 128TB */ +#define NR_CHUNKS_384TB 24576UL /* Number of 16GB chunks for 384TB */ + +#define ADDR_MARK_128TB (1UL << 47) /* First address beyond 128TB */ + +static char *hind_addr(void) +{ + int bits = 48 + rand() % 15; + + return (char *) (1UL << bits); +} + +static int validate_addr(char *ptr, int high_addr) +{ + unsigned long addr = (unsigned long) ptr; + + if (high_addr) { + if (addr < ADDR_MARK_128TB) { + printf("Bad address %lx\n", addr); + return 1; + } + return 0; + } + + if (addr > ADDR_MARK_128TB) { + printf("Bad address %lx\n", addr); + return 1; + } + return 0; +} + +static int validate_lower_address_hint(void) +{ + char *ptr; + + ptr = mmap((void *) (1UL << 45), MAP_CHUNK_SIZE, PROT_READ | + PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); + + if (ptr == MAP_FAILED) + return 0; + + return 1; +} + +int main(int argc, char *argv[]) +{ + char *ptr[NR_CHUNKS_128TB]; + char *hptr[NR_CHUNKS_384TB]; + char *hint; + unsigned long i, lchunks, hchunks; + + for (i = 0; i < NR_CHUNKS_128TB; i++) { + ptr[i] = mmap(NULL, MAP_CHUNK_SIZE, PROT_READ | PROT_WRITE, + MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); + + if (ptr[i] == MAP_FAILED) { + if (validate_lower_address_hint()) + return 1; + break; + } + + if (validate_addr(ptr[i], 0)) + return 1; + } + lchunks = i; + + for (i = 0; i < NR_CHUNKS_384TB; i++) { + hint = hind_addr(); + hptr[i] = mmap(hint, MAP_CHUNK_SIZE, PROT_READ | PROT_WRITE, + MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); + + if (hptr[i] == MAP_FAILED) + break; + + if (validate_addr(hptr[i], 1)) + return 1; + } + hchunks = i; + + for (i = 0; i < lchunks; i++) + munmap(ptr[i], MAP_CHUNK_SIZE); + + for (i = 0; i < hchunks; i++) + munmap(hptr[i], MAP_CHUNK_SIZE); + + return 0; +} -- 2.20.1