Commit 35edbaa0 authored by Sudarsan Mahendran's avatar Sudarsan Mahendran Committed by Andrew Morton
Browse files

selftests/mm: pass filename as input param to VM_PFNMAP tests 

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.txt
	TAP version 13
	1..1
	# Starting 1 tests from 1 test cases.
	#  RUN           pfnmap.madvise_disallowed ...
	#      SKIP      Invalid file: 'randfile.txt'. Not pfnmap'ed

Link: https://lkml.kernel.org/r/20250805013629.47629-1-sudarsanm@google.com


Signed-off-by: default avatarSudarsan Mahendran <sudarsanm@google.com>
Acked-by: default avatarDavid Hildenbrand <david@redhat.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 7cbce1ea

tools/testing/selftests/mm/pfnmap.c

+34 −14
Original line number Diff line number Diff line 
// 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)

{
@@ -51,7 +53,7 @@ static int test_read_access(char *addr, size_t size, size_t pagesize) 
	return ret;

}



static int find_ram_target(off_t *phys_addr,

static int find_ram_target(off_t *offset,

		unsigned long long pagesize)

{

	unsigned long long start, end;
@@ -91,7 +93,7 @@ static int find_ram_target(off_t *phys_addr, 
		/* We need two pages. */

		if (end > start + 2 * pagesize) {

			fclose(file);

			*phys_addr = start;

			*offset = start;

			return 0;

		}

	}
@@ -100,7 +102,7 @@ static int find_ram_target(off_t *phys_addr, 


FIXTURE(pfnmap)

{

	off_t phys_addr;

	off_t offset;

	size_t pagesize;

	int dev_mem_fd;

	char *addr1;
@@ -113,23 +115,31 @@ FIXTURE_SETUP(pfnmap) 
{

	self->pagesize = getpagesize();



	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");

		if (find_ram_target(&self->offset, self->pagesize))

			SKIP(return,

				   "Cannot find ram target in '/proc/iomem'\n");

	} else {

		self->offset = 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);

			   self->dev_mem_fd, self->offset);

	if (self->addr1 == MAP_FAILED)

		SKIP(return, "Cannot mmap '/dev/mem'\n");

		SKIP(return, "Cannot mmap '%s'\n", file);



	if (!check_vmflag_pfnmap(self->addr1))

		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;
@@ -182,7 +192,7 @@ TEST_F(pfnmap, munmap_split) 
	 */

	self->size2 = self->pagesize;

	self->addr2 = mmap(NULL, self->pagesize, PROT_READ, MAP_SHARED,

			   self->dev_mem_fd, self->phys_addr);

			   self->dev_mem_fd, self->offset);

	ASSERT_NE(self->addr2, MAP_FAILED);

}
@@ -246,4 +256,14 @@ 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);

}

tools/testing/selftests/mm/vm_util.c

+12 −2
Original line number Diff line number Diff line
@@ -402,7 +402,7 @@ unsigned long get_free_hugepages(void) 
	return fhp;

}



bool check_vmflag_io(void *addr)

static bool check_vmflag(void *addr, const char *flag)

{

	char buffer[MAX_LINE_LENGTH];

	const char *flags;
@@ -419,13 +419,23 @@ bool check_vmflag_io(void *addr) 
		if (!flaglen)

			return false;



		if (flaglen == strlen("io") && !memcmp(flags, "io", flaglen))

		if (flaglen == strlen(flag) && !memcmp(flags, flag, flaglen))

			return true;



		flags += flaglen;

	}

}



bool check_vmflag_io(void *addr)

{

	return check_vmflag(addr, "io");

}



bool check_vmflag_pfnmap(void *addr)

{

	return check_vmflag(addr, "pf");

}



/*

 * Open an fd at /proc/$pid/maps and configure procmap_out ready for

 * PROCMAP_QUERY query. Returns 0 on success, or an error code otherwise.

tools/testing/selftests/mm/vm_util.h

+1 −0
Original line number Diff line number Diff line
@@ -93,6 +93,7 @@ int uffd_register_with_ioctls(int uffd, void *addr, uint64_t len, 
			      bool miss, bool wp, bool minor, uint64_t *ioctls);

unsigned long get_free_hugepages(void);

bool check_vmflag_io(void *addr);

bool check_vmflag_pfnmap(void *addr);

int open_procmap(pid_t pid, struct procmap_fd *procmap_out);

int query_procmap(struct procmap_fd *procmap);

bool find_vma_procmap(struct procmap_fd *procmap, void *address);