Enable these tests to be run on other pfnmap'ed memory like NVIDIA's EGM.

Add '--' as a separator to pass in file path. This allows passing of cmd line arguments to kselftest_harness. Use '/dev/mem' as default filename.

Existing test passes: pfnmap TAP version 13 1..6 # Starting 6 tests from 1 test cases. # PASSED: 6 / 6 tests passed. # Totals: pass:6 fail:0 xfail:0 xpass:0 skip:0 error:0

Pass params to kselftest_harness: pfnmap -r pfnmap:mremap_fixed TAP version 13 1..1 # Starting 1 tests from 1 test cases. # RUN pfnmap.mremap_fixed ... # OK pfnmap.mremap_fixed ok 1 pfnmap.mremap_fixed # PASSED: 1 / 1 tests passed. # Totals: pass:1 fail:0 xfail:0 xpass:0 skip:0 error:0

Pass non-existent file name as input: pfnmap -- /dev/blah TAP version 13 1..6 # Starting 6 tests from 1 test cases. # RUN pfnmap.madvise_disallowed ... # SKIP Cannot open '/dev/blah'

Pass non pfnmap'ed file as input: pfnmap -r pfnmap.madvise_disallowed -- randfile TAP version 13 1..1 # Starting 1 tests from 1 test cases. # RUN pfnmap.madvise_disallowed ... # SKIP Invalid file: 'randfile'. Not pfnmap'ed

Signed-off-by: Sudarsan Mahendran sudarsanm@google.com ---

v1 -> v2: * Add verify_pfnmap func to sanity check the input param * mmap with zero offset if filename != '/dev/mem'

--- tools/testing/selftests/mm/pfnmap.c | 62 ++++++++++++++++++++++++----- 1 file changed, 53 insertions(+), 9 deletions(-)

diff --git a/tools/testing/selftests/mm/pfnmap.c b/tools/testing/selftests/mm/pfnmap.c index 866ac023baf5..e078b961c333 100644 --- a/tools/testing/selftests/mm/pfnmap.c +++ b/tools/testing/selftests/mm/pfnmap.c @@ -1,6 +1,7 @@ // SPDX-License-Identifier: GPL-2.0-only /* - * Basic VM_PFNMAP tests relying on mmap() of '/dev/mem' + * Basic VM_PFNMAP tests relying on mmap() of input file provided. + * Use '/dev/mem' as default. * * Copyright 2025, Red Hat, Inc. * @@ -25,6 +26,7 @@ #include "vm_util.h"

static sigjmp_buf sigjmp_buf_env; +static char *file = "/dev/mem";

static void signal_handler(int sig) { @@ -98,6 +100,30 @@ static int find_ram_target(off_t *phys_addr, return -ENOENT; }

+static int verify_pfnmap(void) +{ + FILE *smaps_fp; + char line[512]; + int found_mmap_entry = 0; + + smaps_fp = fopen("/proc/self/smaps", "r"); + if (!smaps_fp) + return -errno; + while (fgets(line, sizeof(line), smaps_fp) != NULL) { + if (strstr(line, file) && strstr(line, " r--s ")) + found_mmap_entry = 1; + + if (found_mmap_entry && + strncmp(line, "VmFlags:", strlen("VmFlags:")) == 0) { + if (strstr(line, " pf ")) + return 0; + found_mmap_entry = 0; + } + } + fclose(smaps_fp); + return -ENOENT; +} + FIXTURE(pfnmap) { off_t phys_addr; @@ -113,23 +139,31 @@ FIXTURE_SETUP(pfnmap) { self->pagesize = getpagesize();

- /* We'll require two physical pages throughout our tests ... */ - if (find_ram_target(&self->phys_addr, self->pagesize)) - SKIP(return, "Cannot find ram target in '/proc/iomem'\n"); + if (strncmp(file, "/dev/mem", strlen("/dev/mem")) == 0) { + /* We'll require two physical pages throughout our tests ... */ + if (find_ram_target(&self->phys_addr, self->pagesize)) + SKIP(return, + "Cannot find ram target in '/proc/iomem'\n"); + } else { + self->phys_addr = 0; + }

- self->dev_mem_fd = open("/dev/mem", O_RDONLY); + self->dev_mem_fd = open(file, O_RDONLY); if (self->dev_mem_fd < 0) - SKIP(return, "Cannot open '/dev/mem'\n"); + SKIP(return, "Cannot open '%s'\n", file);

self->size1 = self->pagesize * 2; self->addr1 = mmap(NULL, self->size1, PROT_READ, MAP_SHARED, self->dev_mem_fd, self->phys_addr); if (self->addr1 == MAP_FAILED) - SKIP(return, "Cannot mmap '/dev/mem'\n"); + SKIP(return, "Cannot mmap '%s'\n", file); + + if (verify_pfnmap()) + SKIP(return, "Invalid file: '%s'. Not pfnmap'ed\n", file);

/* ... and want to be able to read from them. */ if (test_read_access(self->addr1, self->size1, self->pagesize)) - SKIP(return, "Cannot read-access mmap'ed '/dev/mem'\n"); + SKIP(return, "Cannot read-access mmap'ed '%s'\n", file);

self->size2 = 0; self->addr2 = MAP_FAILED; @@ -246,4 +280,14 @@ TEST_F(pfnmap, fork) ASSERT_EQ(ret, 0); }

-TEST_HARNESS_MAIN +int main(int argc, char **argv) +{ + for (int i = 1; i < argc; i++) { + if (strcmp(argv[i], "--") == 0) { + if (i + 1 < argc && strlen(argv[i + 1]) > 0) + file = argv[i + 1]; + return test_harness_run(i, argv); + } + } + return test_harness_run(argc, argv); +}