diff mbox series

[v33,6/6] selftests: mm: add pagemap ioctl tests

Message ID 20230821141518.870589-7-usama.anjum@collabora.com (mailing list archive)
State New
Headers show
Series Implement IOCTL to get and optionally clear info about PTEs | expand

Commit Message

Muhammad Usama Anjum Aug. 21, 2023, 2:15 p.m. UTC
Add pagemap ioctl tests. Add several different types of tests to judge
the correction of the interface.

Signed-off-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
---
Changes in v30:
- Rebase on top of next-20230815 and resolved conflict on Makefile

Changes in v29:
- Minor improvements and new tests

Changes in v28:
- Add walk_end tests

Changes in v27:
- Open the pagemap file with O_RDONLY
- Use UFFD_USER_MODE_ONLY flag for userfaultfd() syscall

Changes in v26:
- Updates

Changes in v19:
- Incorporated interface changes and update tests

Changes in v18:
- Rebase on top of 20230613 (Resolve conflict in Makefile)
- Add temp files to .gitignore

Changes in v17:
- Rebase on top of next-20230525

Changes in v16:
- Added yet more tests which is a randomization test case to catch the
  corner cases
- Add reset by exclusive PM_SCAN_OP_WP as well

Changes in v13:
- Update tests and rebase Makefile

Changes in v12:
- Updates and add more memory type tests

Changes in v11:
- Rebase on top of next-20230216 and update tests

Chages in v7:
- Add and update all test cases

Changes in v6:
- Rename variables

Changes in v4:
- Updated all the tests to conform to new IOCTL

Changes in v3:
- Add another test to do sanity of flags

Changes in v2:
- Update the tests to use the ioctl interface instead of syscall
---
TAP version 13
1..108
ok 1 sanity_tests_sd Zero range size is valid
ok 2 sanity_tests_sd output buffer must be specified with size
ok 3 sanity_tests_sd output buffer can be 0
ok 4 sanity_tests_sd wrong flag specified
ok 5 sanity_tests_sd flag has extra bits specified
ok 6 sanity_tests_sd no selection mask is specified
ok 7 sanity_tests_sd no return mask is specified
ok 8 sanity_tests_sd wrong return mask specified
ok 9 sanity_tests_sd mixture of correct and wrong flag
ok 10 sanity_tests_sd PAGEMAP_BITS_ALL can be specified with PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC
ok 11 sanity_tests_sd Clear area with larger vec size
ok 12 sanity_tests_sd Repeated pattern of written and non-written pages
ok 13 sanity_tests_sd Repeated pattern of written and non-written pages in parts 3 2 2
ok 14 sanity_tests_sd Repeated pattern of written and non-written pages max_pages
ok 15 sanity_tests_sd only get 2 written pages and clear them as well
ok 16 sanity_tests_sd Two regions
ok 17 sanity_tests_sd Smaller max_pages
ok 18 Smaller vec
ok 19 Walk_end: Same start and end address
ok 20 Walk_end: Same start and end with WP
ok 21 Walk_end: Same start and end with 0 output buffer
ok 22 Walk_end: Big vec
ok 23 Walk_end: vec of minimum length
ok 24 Walk_end: Max pages specified
ok 25 Walk_end: Half max pages
ok 26 Walk_end: 1 max page
ok 27 Walk_end: max pages
ok 28 Walk_end sparse: Big vec
ok 29 Walk_end sparse: vec of minimum length
ok 30 Walk_end sparse: Max pages specified
ok 31 Walk_end sparse: Max pages specified
ok 32 Walk_end sparse: Max pages specified
ok 33 Walk_endsparse : Half max pages
ok 34 Walk_end: 1 max page
ok 35 Page testing: all new pages must not be written (dirty)
ok 36 Page testing: all pages must be written (dirty)
ok 37 Page testing: all pages dirty other than first and the last one
ok 38 Page testing: PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC
ok 39 Page testing: only middle page dirty
ok 40 Page testing: only two middle pages dirty
ok 41 Large Page testing: all new pages must not be written (dirty)
ok 42 Large Page testing: all pages must be written (dirty)
ok 43 Large Page testing: all pages dirty other than first and the last one
ok 44 Large Page testing: PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC
ok 45 Large Page testing: only middle page dirty
ok 46 Large Page testing: only two middle pages dirty
ok 47 Huge page testing: all new pages must not be written (dirty)
ok 48 Huge page testing: all pages must be written (dirty)
ok 49 Huge page testing: all pages dirty other than first and the last one
ok 50 Huge page testing: PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC
ok 51 Huge page testing: only middle page dirty
ok 52 Huge page testing: only two middle pages dirty
ok 53 Hugetlb shmem testing: all new pages must not be written (dirty)
ok 54 Hugetlb shmem testing: all pages must be written (dirty)
ok 55 Hugetlb shmem testing: all pages dirty other than first and the last one
ok 56 Hugetlb shmem testing: PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC
ok 57 Hugetlb shmem testing: only middle page dirty
ok 58 Hugetlb shmem testing: only two middle pages dirty
ok 59 Hugetlb mem testing: all new pages must not be written (dirty)
ok 60 Hugetlb mem testing: all pages must be written (dirty)
ok 61 Hugetlb mem testing: all pages dirty other than first and the last one
ok 62 Hugetlb mem testing: PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC
ok 63 Hugetlb mem testing: only middle page dirty
ok 64 Hugetlb mem testing: only two middle pages dirty
ok 65 File memory testing: all new pages must not be written (dirty)
ok 66 File memory testing: all pages must be written (dirty)
ok 67 File memory testing: all pages dirty other than first and the last one
ok 68 File memory testing: PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC
ok 69 File memory testing: only middle page dirty
ok 70 File memory testing: only two middle pages dirty
ok 71 File anonymous memory testing: all new pages must not be written (dirty)
ok 72 File anonymous memory testing: all pages must be written (dirty)
ok 73 File anonymous memory testing: all pages dirty other than first and the last one
ok 74 File anonymous memory testing: PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC
ok 75 File anonymous memory testing: only middle page dirty
ok 76 File anonymous memory testing: only two middle pages dirty
ok 77 hpage_unit_tests all new huge page must not be written (dirty)
ok 78 hpage_unit_tests all the huge page must not be written
ok 79 hpage_unit_tests all the huge page must be written and clear
ok 80 hpage_unit_tests only middle page written
ok 81 hpage_unit_tests clear first half of huge page
ok 82 hpage_unit_tests clear first half of huge page with limited buffer
ok 83 hpage_unit_tests clear second half huge page
ok 84 hpage_unit_tests get half huge page
ok 85 hpage_unit_tests get half huge page
ok 86 Test test_simple
ok 87 mprotect_tests Both pages written
ok 88 mprotect_tests Both pages are not written (dirty)
ok 89 mprotect_tests Both pages written after remap and mprotect
ok 90 mprotect_tests Clear and make the pages written
ok 91 transact_test count 192
ok 92 transact_test count 0
ok 93 transact_test Extra pages 1 (0.0%), extra thread faults 1.
ok 94 sanity_tests WP op can be specified with !PAGE_IS_WRITTEN
ok 95 sanity_tests required_mask specified
ok 96 sanity_tests anyof_mask specified
ok 97 sanity_tests excluded_mask specified
ok 98 sanity_tests required_mask and anyof_mask specified
ok 99 sanity_tests Get sd and present pages with anyof_mask
ok 100 sanity_tests Get all the pages with required_mask
ok 101 sanity_tests Get sd and present pages with required_mask and anyof_mask
ok 102 sanity_tests Don't get sd pages
ok 103 sanity_tests Don't get present pages
ok 104 sanity_tests Find written present pages with return mask
ok 105 sanity_tests Memory mapped file
ok 106 sanity_tests Read/write to memory
ok 107 unmapped_region_tests Get status of pages
ok 108 userfaultfd_tests all new pages must not be written (dirty)
 # Totals: pass:108 fail:0 xfail:0 xpass:0 skip:0 error:0

selftests
---
 tools/testing/selftests/mm/.gitignore      |    2 +
 tools/testing/selftests/mm/Makefile        |    3 +-
 tools/testing/selftests/mm/config          |    1 +
 tools/testing/selftests/mm/pagemap_ioctl.c | 1660 ++++++++++++++++++++
 tools/testing/selftests/mm/run_vmtests.sh  |    4 +
 5 files changed, 1669 insertions(+), 1 deletion(-)
 create mode 100644 tools/testing/selftests/mm/pagemap_ioctl.c

Comments

Ryan Roberts Nov. 2, 2023, 11:45 a.m. UTC | #1
On 21/08/2023 15:15, Muhammad Usama Anjum wrote:

[...]

> +
> +
> +int init_uffd(void)
> +{
> +	struct uffdio_api uffdio_api;
> +
> +	uffd = syscall(__NR_userfaultfd, O_CLOEXEC | O_NONBLOCK | UFFD_USER_MODE_ONLY);
> +	if (uffd == -1)
> +		ksft_exit_fail_msg("uffd syscall failed\n");
> +
> +	uffdio_api.api = UFFD_API;
> +	uffdio_api.features = UFFD_FEATURE_WP_UNPOPULATED | UFFD_FEATURE_WP_ASYNC |
> +			      UFFD_FEATURE_WP_HUGETLBFS_SHMEM;
> +	if (ioctl(uffd, UFFDIO_API, &uffdio_api))
> +		ksft_exit_fail_msg("UFFDIO_API\n");
> +
> +	if (!(uffdio_api.api & UFFDIO_REGISTER_MODE_WP) ||
> +	    !(uffdio_api.features & UFFD_FEATURE_WP_UNPOPULATED) ||
> +	    !(uffdio_api.features & UFFD_FEATURE_WP_ASYNC) ||
> +	    !(uffdio_api.features & UFFD_FEATURE_WP_HUGETLBFS_SHMEM))
> +		ksft_exit_fail_msg("UFFDIO_API error %llu\n", uffdio_api.api);

Hi,

I've just noticed that this fails on arm64 because the required features are not
available. It's common practice to skip instead of fail for this sort of
condition (and that's how all the other uffd tests work). The current fail
approach creates noise in our CI.

I see this is already in mm-stable so perhaps we can add a patch to fix on top?

Thanks,
Ryan
Muhammad Usama Anjum Nov. 2, 2023, 11:49 a.m. UTC | #2
On 11/2/23 4:45 PM, Ryan Roberts wrote:
> On 21/08/2023 15:15, Muhammad Usama Anjum wrote:
> 
> [...]
> 
>> +
>> +
>> +int init_uffd(void)
>> +{
>> +	struct uffdio_api uffdio_api;
>> +
>> +	uffd = syscall(__NR_userfaultfd, O_CLOEXEC | O_NONBLOCK | UFFD_USER_MODE_ONLY);
>> +	if (uffd == -1)
>> +		ksft_exit_fail_msg("uffd syscall failed\n");
>> +
>> +	uffdio_api.api = UFFD_API;
>> +	uffdio_api.features = UFFD_FEATURE_WP_UNPOPULATED | UFFD_FEATURE_WP_ASYNC |
>> +			      UFFD_FEATURE_WP_HUGETLBFS_SHMEM;
>> +	if (ioctl(uffd, UFFDIO_API, &uffdio_api))
>> +		ksft_exit_fail_msg("UFFDIO_API\n");
>> +
>> +	if (!(uffdio_api.api & UFFDIO_REGISTER_MODE_WP) ||
>> +	    !(uffdio_api.features & UFFD_FEATURE_WP_UNPOPULATED) ||
>> +	    !(uffdio_api.features & UFFD_FEATURE_WP_ASYNC) ||
>> +	    !(uffdio_api.features & UFFD_FEATURE_WP_HUGETLBFS_SHMEM))
>> +		ksft_exit_fail_msg("UFFDIO_API error %llu\n", uffdio_api.api);
> 
> Hi,
> 
> I've just noticed that this fails on arm64 because the required features are not
> available. It's common practice to skip instead of fail for this sort of
> condition (and that's how all the other uffd tests work). The current fail
> approach creates noise in our CI.
> 
> I see this is already in mm-stable so perhaps we can add a patch to fix on top?
Yeah, we can add a patch to skip all the tests instead of failing here. Let
me send a patch this week.

> 
> Thanks,
> Ryan
> 
>
Ryan Roberts Nov. 2, 2023, 12:04 p.m. UTC | #3
On 02/11/2023 11:49, Muhammad Usama Anjum wrote:
> On 11/2/23 4:45 PM, Ryan Roberts wrote:
>> On 21/08/2023 15:15, Muhammad Usama Anjum wrote:
>>
>> [...]
>>
>>> +
>>> +
>>> +int init_uffd(void)
>>> +{
>>> +	struct uffdio_api uffdio_api;
>>> +
>>> +	uffd = syscall(__NR_userfaultfd, O_CLOEXEC | O_NONBLOCK | UFFD_USER_MODE_ONLY);
>>> +	if (uffd == -1)
>>> +		ksft_exit_fail_msg("uffd syscall failed\n");
>>> +
>>> +	uffdio_api.api = UFFD_API;
>>> +	uffdio_api.features = UFFD_FEATURE_WP_UNPOPULATED | UFFD_FEATURE_WP_ASYNC |
>>> +			      UFFD_FEATURE_WP_HUGETLBFS_SHMEM;
>>> +	if (ioctl(uffd, UFFDIO_API, &uffdio_api))
>>> +		ksft_exit_fail_msg("UFFDIO_API\n");
>>> +
>>> +	if (!(uffdio_api.api & UFFDIO_REGISTER_MODE_WP) ||
>>> +	    !(uffdio_api.features & UFFD_FEATURE_WP_UNPOPULATED) ||
>>> +	    !(uffdio_api.features & UFFD_FEATURE_WP_ASYNC) ||
>>> +	    !(uffdio_api.features & UFFD_FEATURE_WP_HUGETLBFS_SHMEM))
>>> +		ksft_exit_fail_msg("UFFDIO_API error %llu\n", uffdio_api.api);
>>
>> Hi,
>>
>> I've just noticed that this fails on arm64 because the required features are not
>> available. It's common practice to skip instead of fail for this sort of
>> condition (and that's how all the other uffd tests work). The current fail
>> approach creates noise in our CI.
>>
>> I see this is already in mm-stable so perhaps we can add a patch to fix on top?
> Yeah, we can add a patch to skip all the tests instead of failing here. Let
> me send a patch this week.

Thats great - thanks for the fast response!

> 
>>
>> Thanks,
>> Ryan
>>
>>
>
diff mbox series

Patch

diff --git a/tools/testing/selftests/mm/.gitignore b/tools/testing/selftests/mm/.gitignore
index cdc9ce4426b95..cc920c79ff1c3 100644
--- a/tools/testing/selftests/mm/.gitignore
+++ b/tools/testing/selftests/mm/.gitignore
@@ -18,6 +18,8 @@  mremap_dontunmap
 mremap_test
 on-fault-limit
 transhuge-stress
+pagemap_ioctl
+*.tmp*
 protection_keys
 protection_keys_32
 protection_keys_64
diff --git a/tools/testing/selftests/mm/Makefile b/tools/testing/selftests/mm/Makefile
index 6a9fc5693145f..2a89989afafc6 100644
--- a/tools/testing/selftests/mm/Makefile
+++ b/tools/testing/selftests/mm/Makefile
@@ -33,7 +33,7 @@  endif
 MAKEFLAGS += --no-builtin-rules
 
 CFLAGS = -Wall -I $(top_srcdir) $(EXTRA_CFLAGS) $(KHDR_INCLUDES)
-LDLIBS = -lrt -lpthread
+LDLIBS = -lrt -lpthread -lm
 
 TEST_GEN_FILES = cow
 TEST_GEN_FILES += compaction_test
@@ -60,6 +60,7 @@  TEST_GEN_FILES += mrelease_test
 TEST_GEN_FILES += mremap_dontunmap
 TEST_GEN_FILES += mremap_test
 TEST_GEN_FILES += on-fault-limit
+TEST_GEN_PROGS += pagemap_ioctl
 TEST_GEN_FILES += thuge-gen
 TEST_GEN_FILES += transhuge-stress
 TEST_GEN_FILES += uffd-stress
diff --git a/tools/testing/selftests/mm/config b/tools/testing/selftests/mm/config
index be087c4bc3961..4309916f629e3 100644
--- a/tools/testing/selftests/mm/config
+++ b/tools/testing/selftests/mm/config
@@ -1,5 +1,6 @@ 
 CONFIG_SYSVIPC=y
 CONFIG_USERFAULTFD=y
+CONFIG_PTE_MARKER_UFFD_WP=y
 CONFIG_TEST_VMALLOC=m
 CONFIG_DEVICE_PRIVATE=y
 CONFIG_TEST_HMM=m
diff --git a/tools/testing/selftests/mm/pagemap_ioctl.c b/tools/testing/selftests/mm/pagemap_ioctl.c
new file mode 100644
index 0000000000000..0161fb49fc6ef
--- /dev/null
+++ b/tools/testing/selftests/mm/pagemap_ioctl.c
@@ -0,0 +1,1660 @@ 
+// SPDX-License-Identifier: GPL-2.0
+#define _GNU_SOURCE
+#include <stdio.h>
+#include <fcntl.h>
+#include <string.h>
+#include <sys/mman.h>
+#include <errno.h>
+#include <malloc.h>
+#include "vm_util.h"
+#include "../kselftest.h"
+#include <linux/types.h>
+#include <linux/memfd.h>
+#include <linux/userfaultfd.h>
+#include <linux/fs.h>
+#include <sys/ioctl.h>
+#include <sys/stat.h>
+#include <math.h>
+#include <asm/unistd.h>
+#include <pthread.h>
+#include <sys/resource.h>
+#include <assert.h>
+#include <sys/ipc.h>
+#include <sys/shm.h>
+
+#define PAGEMAP_BITS_ALL		(PAGE_IS_WPALLOWED | PAGE_IS_WRITTEN |	\
+					 PAGE_IS_FILE | PAGE_IS_PRESENT |	\
+					 PAGE_IS_SWAPPED | PAGE_IS_PFNZERO |	\
+					 PAGE_IS_HUGE)
+#define PAGEMAP_NON_WRITTEN_BITS	(PAGE_IS_WPALLOWED | PAGE_IS_FILE |	\
+					 PAGE_IS_PRESENT | PAGE_IS_SWAPPED |	\
+					 PAGE_IS_PFNZERO | PAGE_IS_HUGE)
+
+#define TEST_ITERATIONS 100
+#define PAGEMAP "/proc/self/pagemap"
+int pagemap_fd;
+int uffd;
+int page_size;
+int hpage_size;
+
+#define LEN(region)	((region.end - region.start)/page_size)
+
+static long pagemap_ioctl(void *start, int len, void *vec, int vec_len, int flag,
+			  int max_pages, long required_mask, long anyof_mask, long excluded_mask,
+			  long return_mask)
+{
+	struct pm_scan_arg arg;
+
+	arg.start = (uintptr_t)start;
+	arg.end = (uintptr_t)(start + len);
+	arg.vec = (uintptr_t)vec;
+	arg.vec_len = vec_len;
+	arg.flags = flag;
+	arg.size = sizeof(struct pm_scan_arg);
+	arg.max_pages = max_pages;
+	arg.category_mask = required_mask;
+	arg.category_anyof_mask = anyof_mask;
+	arg.category_inverted = excluded_mask;
+	arg.return_mask = return_mask;
+
+	return ioctl(pagemap_fd, PAGEMAP_SCAN, &arg);
+}
+
+static long pagemap_ioc(void *start, int len, void *vec, int vec_len, int flag,
+			int max_pages, long required_mask, long anyof_mask, long excluded_mask,
+			long return_mask, long *walk_end)
+{
+	struct pm_scan_arg arg;
+	int ret;
+
+	arg.start = (uintptr_t)start;
+	arg.end = (uintptr_t)(start + len);
+	arg.vec = (uintptr_t)vec;
+	arg.vec_len = vec_len;
+	arg.flags = flag;
+	arg.size = sizeof(struct pm_scan_arg);
+	arg.max_pages = max_pages;
+	arg.category_mask = required_mask;
+	arg.category_anyof_mask = anyof_mask;
+	arg.category_inverted = excluded_mask;
+	arg.return_mask = return_mask;
+
+	ret = ioctl(pagemap_fd, PAGEMAP_SCAN, &arg);
+
+	if (walk_end)
+		*walk_end = arg.walk_end;
+
+	return ret;
+}
+
+
+int init_uffd(void)
+{
+	struct uffdio_api uffdio_api;
+
+	uffd = syscall(__NR_userfaultfd, O_CLOEXEC | O_NONBLOCK | UFFD_USER_MODE_ONLY);
+	if (uffd == -1)
+		ksft_exit_fail_msg("uffd syscall failed\n");
+
+	uffdio_api.api = UFFD_API;
+	uffdio_api.features = UFFD_FEATURE_WP_UNPOPULATED | UFFD_FEATURE_WP_ASYNC |
+			      UFFD_FEATURE_WP_HUGETLBFS_SHMEM;
+	if (ioctl(uffd, UFFDIO_API, &uffdio_api))
+		ksft_exit_fail_msg("UFFDIO_API\n");
+
+	if (!(uffdio_api.api & UFFDIO_REGISTER_MODE_WP) ||
+	    !(uffdio_api.features & UFFD_FEATURE_WP_UNPOPULATED) ||
+	    !(uffdio_api.features & UFFD_FEATURE_WP_ASYNC) ||
+	    !(uffdio_api.features & UFFD_FEATURE_WP_HUGETLBFS_SHMEM))
+		ksft_exit_fail_msg("UFFDIO_API error %llu\n", uffdio_api.api);
+
+	return 0;
+}
+
+int wp_init(void *lpBaseAddress, int dwRegionSize)
+{
+	struct uffdio_register uffdio_register;
+	struct uffdio_writeprotect wp;
+
+	uffdio_register.range.start = (unsigned long)lpBaseAddress;
+	uffdio_register.range.len = dwRegionSize;
+	uffdio_register.mode = UFFDIO_REGISTER_MODE_WP;
+	if (ioctl(uffd, UFFDIO_REGISTER, &uffdio_register))
+		ksft_exit_fail_msg("ioctl(UFFDIO_REGISTER) %d %s\n", errno, strerror(errno));
+
+	if (!(uffdio_register.ioctls & UFFDIO_WRITEPROTECT))
+		ksft_exit_fail_msg("ioctl set is incorrect\n");
+
+	wp.range.start = (unsigned long)lpBaseAddress;
+	wp.range.len = dwRegionSize;
+	wp.mode = UFFDIO_WRITEPROTECT_MODE_WP;
+
+	if (ioctl(uffd, UFFDIO_WRITEPROTECT, &wp))
+		ksft_exit_fail_msg("ioctl(UFFDIO_WRITEPROTECT)\n");
+
+	return 0;
+}
+
+int wp_free(void *lpBaseAddress, int dwRegionSize)
+{
+	struct uffdio_register uffdio_register;
+
+	uffdio_register.range.start = (unsigned long)lpBaseAddress;
+	uffdio_register.range.len = dwRegionSize;
+	uffdio_register.mode = UFFDIO_REGISTER_MODE_WP;
+	if (ioctl(uffd, UFFDIO_UNREGISTER, &uffdio_register.range))
+		ksft_exit_fail_msg("ioctl unregister failure\n");
+	return 0;
+}
+
+int wp_addr_range(void *lpBaseAddress, int dwRegionSize)
+{
+	if (pagemap_ioctl(lpBaseAddress, dwRegionSize, NULL, 0,
+			  PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC,
+			  0, PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN) < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", 1, errno, strerror(errno));
+
+	return 0;
+}
+
+void *gethugetlb_mem(int size, int *shmid)
+{
+	char *mem;
+
+	if (shmid) {
+		*shmid = shmget(2, size, SHM_HUGETLB | IPC_CREAT | SHM_R | SHM_W);
+		if (*shmid < 0)
+			return NULL;
+
+		mem = shmat(*shmid, 0, 0);
+		if (mem == (char *)-1) {
+			shmctl(*shmid, IPC_RMID, NULL);
+			ksft_exit_fail_msg("Shared memory attach failure\n");
+		}
+	} else {
+		mem = mmap(NULL, size, PROT_READ | PROT_WRITE,
+			   MAP_ANONYMOUS | MAP_HUGETLB | MAP_PRIVATE, -1, 0);
+		if (mem == MAP_FAILED)
+			return NULL;
+	}
+
+	return mem;
+}
+
+int userfaultfd_tests(void)
+{
+	int mem_size, vec_size, written, num_pages = 16;
+	char *mem, *vec;
+
+	mem_size = num_pages * page_size;
+	mem = mmap(NULL, mem_size, PROT_NONE, MAP_PRIVATE | MAP_ANON, -1, 0);
+	if (mem == MAP_FAILED)
+		ksft_exit_fail_msg("error nomem\n");
+
+	wp_init(mem, mem_size);
+
+	/* Change protection of pages differently */
+	mprotect(mem, mem_size/8, PROT_READ|PROT_WRITE);
+	mprotect(mem + 1 * mem_size/8, mem_size/8, PROT_READ);
+	mprotect(mem + 2 * mem_size/8, mem_size/8, PROT_READ|PROT_WRITE);
+	mprotect(mem + 3 * mem_size/8, mem_size/8, PROT_READ);
+	mprotect(mem + 4 * mem_size/8, mem_size/8, PROT_READ|PROT_WRITE);
+	mprotect(mem + 5 * mem_size/8, mem_size/8, PROT_NONE);
+	mprotect(mem + 6 * mem_size/8, mem_size/8, PROT_READ|PROT_WRITE);
+	mprotect(mem + 7 * mem_size/8, mem_size/8, PROT_READ);
+
+	wp_addr_range(mem + (mem_size/16), mem_size - 2 * (mem_size/8));
+	wp_addr_range(mem, mem_size);
+
+	vec_size = mem_size/page_size;
+	vec = malloc(sizeof(struct page_region) * vec_size);
+
+	written = pagemap_ioctl(mem, mem_size, vec, 1, PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC,
+				vec_size - 2, PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN);
+	if (written < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", written, errno, strerror(errno));
+
+	ksft_test_result(written == 0, "%s all new pages must not be written (dirty)\n", __func__);
+
+	wp_free(mem, mem_size);
+	munmap(mem, mem_size);
+	free(vec);
+	return 0;
+}
+
+int get_reads(struct page_region *vec, int vec_size)
+{
+	int i, sum = 0;
+
+	for (i = 0; i < vec_size; i++)
+		sum += LEN(vec[i]);
+
+	return sum;
+}
+
+int sanity_tests_sd(void)
+{
+	int mem_size, vec_size, ret, ret2, ret3, i, num_pages = 1000, total_pages = 0;
+	int total_writes, total_reads, reads, count;
+	struct page_region *vec, *vec2;
+	char *mem, *m[2];
+	long walk_end;
+
+	vec_size = num_pages/2;
+	mem_size = num_pages * page_size;
+
+	vec = malloc(sizeof(struct page_region) * vec_size);
+	if (!vec)
+		ksft_exit_fail_msg("error nomem\n");
+
+	vec2 = malloc(sizeof(struct page_region) * vec_size);
+	if (!vec2)
+		ksft_exit_fail_msg("error nomem\n");
+
+	mem = mmap(NULL, mem_size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0);
+	if (mem == MAP_FAILED)
+		ksft_exit_fail_msg("error nomem\n");
+
+	wp_init(mem, mem_size);
+	wp_addr_range(mem, mem_size);
+
+	/* 1. wrong operation */
+	ksft_test_result(pagemap_ioctl(mem, 0, vec, vec_size, 0,
+				       0, PAGEMAP_BITS_ALL, 0, 0, PAGEMAP_BITS_ALL) == 0,
+			 "%s Zero range size is valid\n", __func__);
+
+	ksft_test_result(pagemap_ioctl(mem, mem_size, NULL, vec_size, 0,
+				       0, PAGEMAP_BITS_ALL, 0, 0, PAGEMAP_BITS_ALL) < 0,
+			 "%s output buffer must be specified with size\n", __func__);
+
+	ksft_test_result(pagemap_ioctl(mem, mem_size, vec, 0, 0,
+				       0, PAGEMAP_BITS_ALL, 0, 0, PAGEMAP_BITS_ALL) == 0,
+			 "%s output buffer can be 0\n", __func__);
+
+	ksft_test_result(pagemap_ioctl(mem, mem_size, 0, 0, 0,
+				       0, PAGEMAP_BITS_ALL, 0, 0, PAGEMAP_BITS_ALL) == 0,
+			 "%s output buffer can be 0\n", __func__);
+
+	ksft_test_result(pagemap_ioctl(mem, mem_size, vec, vec_size, -1,
+				       0, PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN) < 0,
+			 "%s wrong flag specified\n", __func__);
+
+	ksft_test_result(pagemap_ioctl(mem, mem_size, vec, vec_size,
+				       PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC | 0xFF,
+				       0, PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN) < 0,
+			 "%s flag has extra bits specified\n", __func__);
+
+	ksft_test_result(pagemap_ioctl(mem, mem_size, vec, vec_size, 0,
+				       0, 0, 0, 0, PAGE_IS_WRITTEN) >= 0,
+			 "%s no selection mask is specified\n", __func__);
+
+	ksft_test_result(pagemap_ioctl(mem, mem_size, vec, vec_size, 0,
+				       0, PAGE_IS_WRITTEN, PAGE_IS_WRITTEN, 0, 0) == 0,
+			 "%s no return mask is specified\n", __func__);
+
+	ksft_test_result(pagemap_ioctl(mem, mem_size, vec, vec_size, 0,
+				       0, PAGE_IS_WRITTEN, 0, 0, 0x1000) < 0,
+			 "%s wrong return mask specified\n", __func__);
+
+	ksft_test_result(pagemap_ioctl(mem, mem_size, vec, vec_size,
+				       PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC,
+				       0, 0xFFF, PAGE_IS_WRITTEN, 0, PAGE_IS_WRITTEN) < 0,
+			 "%s mixture of correct and wrong flag\n", __func__);
+
+	ksft_test_result(pagemap_ioctl(mem, mem_size, vec, vec_size,
+				       PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC,
+				       0, 0, 0, PAGEMAP_BITS_ALL, PAGE_IS_WRITTEN) >= 0,
+			 "%s PAGEMAP_BITS_ALL can be specified with PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC\n",
+			 __func__);
+
+	/* 2. Clear area with larger vec size */
+	ret = pagemap_ioctl(mem, mem_size, vec, vec_size,
+			    PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC, 0,
+			    PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN);
+	ksft_test_result(ret >= 0, "%s Clear area with larger vec size\n", __func__);
+
+	/* 3. Repeated pattern of written and non-written pages */
+	for (i = 0; i < mem_size; i += 2 * page_size)
+		mem[i]++;
+
+	ret = pagemap_ioctl(mem, mem_size, vec, vec_size, 0, 0, PAGE_IS_WRITTEN, 0,
+			    0, PAGE_IS_WRITTEN);
+	if (ret < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+
+	ksft_test_result(ret == mem_size/(page_size * 2),
+			 "%s Repeated pattern of written and non-written pages\n", __func__);
+
+	/* 4. Repeated pattern of written and non-written pages in parts */
+	ret = pagemap_ioctl(mem, mem_size, vec, vec_size,
+			    PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC,
+			    num_pages/2 - 2, PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN);
+	if (ret < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+
+	ret2 = pagemap_ioctl(mem, mem_size, vec, 2, 0, 0, PAGE_IS_WRITTEN, 0, 0,
+			     PAGE_IS_WRITTEN);
+	if (ret2 < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", ret2, errno, strerror(errno));
+
+	ret3 = pagemap_ioctl(mem, mem_size, vec, vec_size,
+			     PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC,
+			     0, PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN);
+	if (ret3 < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", ret3, errno, strerror(errno));
+
+	ksft_test_result((ret + ret3) == num_pages/2 && ret2 == 2,
+			 "%s Repeated pattern of written and non-written pages in parts %d %d %d\n",
+			 __func__, ret, ret3, ret2);
+
+	/* 5. Repeated pattern of written and non-written pages max_pages */
+	for (i = 0; i < mem_size; i += 2 * page_size)
+		mem[i]++;
+	mem[(mem_size/page_size - 1) * page_size]++;
+
+	ret = pagemap_ioctl(mem, mem_size, vec, vec_size,
+			    PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC,
+			    num_pages/2, PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN);
+	if (ret < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+
+	ret2 = pagemap_ioctl(mem, mem_size, vec, vec_size,
+			     PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC,
+			     0, PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN);
+	if (ret2 < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", ret2, errno, strerror(errno));
+
+	ksft_test_result(ret == num_pages/2 && ret2 == 1,
+			 "%s Repeated pattern of written and non-written pages max_pages\n",
+			 __func__);
+
+	/* 6. only get 2 dirty pages and clear them as well */
+	vec_size = mem_size/page_size;
+	memset(mem, -1, mem_size);
+
+	/* get and clear second and third pages */
+	ret = pagemap_ioctl(mem + page_size, 2 * page_size, vec, 1,
+			    PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC,
+			    2, PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN);
+	if (ret < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+
+	ret2 = pagemap_ioctl(mem, mem_size, vec2, vec_size, 0, 0,
+			      PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN);
+	if (ret2 < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", ret2, errno, strerror(errno));
+
+	ksft_test_result(ret == 1 && LEN(vec[0]) == 2 &&
+			 vec[0].start == (uintptr_t)(mem + page_size) &&
+			 ret2 == 2 && LEN(vec2[0]) == 1 && vec2[0].start == (uintptr_t)mem &&
+			 LEN(vec2[1]) == vec_size - 3 &&
+			 vec2[1].start == (uintptr_t)(mem + 3 * page_size),
+			 "%s only get 2 written pages and clear them as well\n", __func__);
+
+	wp_free(mem, mem_size);
+	munmap(mem, mem_size);
+
+	/* 7. Two regions */
+	m[0] = mmap(NULL, mem_size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0);
+	if (m[0] == MAP_FAILED)
+		ksft_exit_fail_msg("error nomem\n");
+	m[1] = mmap(NULL, mem_size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0);
+	if (m[1] == MAP_FAILED)
+		ksft_exit_fail_msg("error nomem\n");
+
+	wp_init(m[0], mem_size);
+	wp_init(m[1], mem_size);
+	wp_addr_range(m[0], mem_size);
+	wp_addr_range(m[1], mem_size);
+
+	memset(m[0], 'a', mem_size);
+	memset(m[1], 'b', mem_size);
+
+	wp_addr_range(m[0], mem_size);
+
+	ret = pagemap_ioctl(m[1], mem_size, vec, 1, 0, 0, PAGE_IS_WRITTEN, 0, 0,
+			    PAGE_IS_WRITTEN);
+	if (ret < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+
+	ksft_test_result(ret == 1 && LEN(vec[0]) == mem_size/page_size,
+			 "%s Two regions\n", __func__);
+
+	wp_free(m[0], mem_size);
+	wp_free(m[1], mem_size);
+	munmap(m[0], mem_size);
+	munmap(m[1], mem_size);
+
+	free(vec);
+	free(vec2);
+
+	/* 8. Smaller vec */
+	mem_size = 1050 * page_size;
+	vec_size = mem_size/(page_size*2);
+
+	vec = malloc(sizeof(struct page_region) * vec_size);
+	if (!vec)
+		ksft_exit_fail_msg("error nomem\n");
+
+	mem = mmap(NULL, mem_size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0);
+	if (mem == MAP_FAILED)
+		ksft_exit_fail_msg("error nomem\n");
+
+	wp_init(mem, mem_size);
+	wp_addr_range(mem, mem_size);
+
+	ret = pagemap_ioctl(mem, mem_size, vec, vec_size,
+			    PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC, 0,
+			    PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN);
+	if (ret < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+
+	for (i = 0; i < mem_size/page_size; i += 2)
+		mem[i * page_size]++;
+
+	ret = pagemap_ioctl(mem, mem_size, vec, vec_size,
+			    PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC,
+			    mem_size/(page_size*5), PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN);
+	if (ret < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+
+	total_pages += ret;
+
+	ret = pagemap_ioctl(mem, mem_size, vec, vec_size,
+			    PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC,
+			    mem_size/(page_size*5), PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN);
+	if (ret < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+
+	total_pages += ret;
+
+	ret = pagemap_ioctl(mem, mem_size, vec, vec_size,
+			    PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC,
+			    mem_size/(page_size*5), PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN);
+	if (ret < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+
+	total_pages += ret;
+
+	ksft_test_result(total_pages == mem_size/(page_size*2), "%s Smaller max_pages\n", __func__);
+
+	free(vec);
+	wp_free(mem, mem_size);
+	munmap(mem, mem_size);
+	total_pages = 0;
+
+	/* 9. Smaller vec */
+	mem_size = 10000 * page_size;
+	vec_size = 50;
+
+	vec = malloc(sizeof(struct page_region) * vec_size);
+	if (!vec)
+		ksft_exit_fail_msg("error nomem\n");
+
+	mem = mmap(NULL, mem_size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0);
+	if (mem == MAP_FAILED)
+		ksft_exit_fail_msg("error nomem\n");
+
+	wp_init(mem, mem_size);
+	wp_addr_range(mem, mem_size);
+
+	for (count = 0; count < TEST_ITERATIONS; count++) {
+		total_writes = total_reads = 0;
+		walk_end = (long)mem;
+
+		for (i = 0; i < mem_size; i += page_size) {
+			if (rand() % 2) {
+				mem[i]++;
+				total_writes++;
+			}
+		}
+
+		while (total_reads < total_writes) {
+			ret = pagemap_ioc((void *)walk_end, mem_size-(walk_end - (long)mem), vec,
+					  vec_size, PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC,
+					  0, PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN, &walk_end);
+			if (ret < 0)
+				ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+
+			if (ret > vec_size)
+				break;
+
+			reads = get_reads(vec, ret);
+			total_reads += reads;
+		}
+
+		if (total_reads != total_writes)
+			break;
+	}
+
+	ksft_test_result(count == TEST_ITERATIONS, "Smaller vec\n");
+
+	free(vec);
+	wp_free(mem, mem_size);
+	munmap(mem, mem_size);
+
+	/* 10. Walk_end tester */
+	vec_size = 1000;
+	mem_size = vec_size * page_size;
+
+	vec = malloc(sizeof(struct page_region) * vec_size);
+	if (!vec)
+		ksft_exit_fail_msg("error nomem\n");
+
+	mem = mmap(NULL, mem_size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0);
+	if (mem == MAP_FAILED)
+		ksft_exit_fail_msg("error nomem\n");
+
+	wp_init(mem, mem_size);
+	wp_addr_range(mem, mem_size);
+
+	memset(mem, 0, mem_size);
+
+	ret = pagemap_ioc(mem, 0, vec, vec_size, 0,
+			  0, PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN, &walk_end);
+	if (ret < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+	ksft_test_result(ret == 0 && walk_end == (long)mem,
+			 "Walk_end: Same start and end address\n");
+
+	ret = pagemap_ioc(mem, 0, vec, vec_size, PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC,
+			  0, PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN, &walk_end);
+	if (ret < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+	ksft_test_result(ret == 0 && walk_end == (long)mem,
+			 "Walk_end: Same start and end with WP\n");
+
+	ret = pagemap_ioc(mem, 0, vec, 0, PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC,
+			  0, PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN, &walk_end);
+	if (ret < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+	ksft_test_result(ret == 0 && walk_end == (long)mem,
+			 "Walk_end: Same start and end with 0 output buffer\n");
+
+	ret = pagemap_ioc(mem, mem_size, vec, vec_size, 0,
+			  0, PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN, &walk_end);
+	if (ret < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+	ksft_test_result(ret == 1 && walk_end == (long)(mem + mem_size),
+			 "Walk_end: Big vec\n");
+
+	ret = pagemap_ioc(mem, mem_size, vec, 1, 0,
+			  0, PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN, &walk_end);
+	if (ret < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+	ksft_test_result(ret == 1 && walk_end == (long)(mem + mem_size),
+			 "Walk_end: vec of minimum length\n");
+
+	ret = pagemap_ioc(mem, mem_size, vec, 1, 0,
+			  vec_size, PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN, &walk_end);
+	if (ret < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+	ksft_test_result(ret == 1 && walk_end == (long)(mem + mem_size),
+			 "Walk_end: Max pages specified\n");
+
+	ret = pagemap_ioc(mem, mem_size, vec, vec_size, 0,
+			  vec_size/2, PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN, &walk_end);
+	if (ret < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+	ksft_test_result(ret == 1 && walk_end == (long)(mem + mem_size/2),
+			 "Walk_end: Half max pages\n");
+
+	ret = pagemap_ioc(mem, mem_size, vec, vec_size, 0,
+			  1, PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN, &walk_end);
+	if (ret < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+	ksft_test_result(ret == 1 && walk_end == (long)(mem + page_size),
+			 "Walk_end: 1 max page\n");
+
+	ret = pagemap_ioc(mem, mem_size, vec, vec_size, 0,
+			  -1, PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN, &walk_end);
+	if (ret < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+	ksft_test_result(ret == 1 && walk_end == (long)(mem + mem_size),
+			 "Walk_end: max pages\n");
+
+	wp_addr_range(mem, mem_size);
+	for (i = 0; i < mem_size; i += 2 * page_size)
+		mem[i]++;
+
+	ret = pagemap_ioc(mem, mem_size, vec, vec_size, 0,
+			  0, PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN, &walk_end);
+	if (ret < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+	ksft_test_result(ret == vec_size/2 && walk_end == (long)(mem + mem_size),
+			 "Walk_end sparse: Big vec\n");
+
+	ret = pagemap_ioc(mem, mem_size, vec, 1, 0,
+			  0, PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN, &walk_end);
+	if (ret < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+	ksft_test_result(ret == 1 && walk_end == (long)(mem + page_size * 2),
+			 "Walk_end sparse: vec of minimum length\n");
+
+	ret = pagemap_ioc(mem, mem_size, vec, 1, 0,
+			  vec_size, PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN, &walk_end);
+	if (ret < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+	ksft_test_result(ret == 1 && walk_end == (long)(mem + page_size * 2),
+			 "Walk_end sparse: Max pages specified\n");
+
+	ret = pagemap_ioc(mem, mem_size, vec, vec_size/2, 0,
+			  vec_size, PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN, &walk_end);
+	if (ret < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+	ksft_test_result(ret == vec_size/2 && walk_end == (long)(mem + mem_size),
+			 "Walk_end sparse: Max pages specified\n");
+
+	ret = pagemap_ioc(mem, mem_size, vec, vec_size, 0,
+			  vec_size, PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN, &walk_end);
+	if (ret < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+	ksft_test_result(ret == vec_size/2 && walk_end == (long)(mem + mem_size),
+			 "Walk_end sparse: Max pages specified\n");
+
+	ret = pagemap_ioc(mem, mem_size, vec, vec_size, 0,
+			  vec_size/2, PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN, &walk_end);
+	if (ret < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+	ksft_test_result(ret == vec_size/2 && walk_end == (long)(mem + mem_size),
+			 "Walk_endsparse : Half max pages\n");
+
+	ret = pagemap_ioc(mem, mem_size, vec, vec_size, 0,
+			  1, PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN, &walk_end);
+	if (ret < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+	ksft_test_result(ret == 1 && walk_end == (long)(mem + page_size * 2),
+			 "Walk_end: 1 max page\n");
+
+	free(vec);
+	wp_free(mem, mem_size);
+	munmap(mem, mem_size);
+
+	return 0;
+}
+
+int base_tests(char *prefix, char *mem, int mem_size, int skip)
+{
+	int vec_size, written;
+	struct page_region *vec, *vec2;
+
+	if (skip) {
+		ksft_test_result_skip("%s all new pages must not be written (dirty)\n", prefix);
+		ksft_test_result_skip("%s all pages must be written (dirty)\n", prefix);
+		ksft_test_result_skip("%s all pages dirty other than first and the last one\n",
+				      prefix);
+		ksft_test_result_skip("%s PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC\n", prefix);
+		ksft_test_result_skip("%s only middle page dirty\n", prefix);
+		ksft_test_result_skip("%s only two middle pages dirty\n", prefix);
+		return 0;
+	}
+
+	vec_size = mem_size/page_size;
+	vec = malloc(sizeof(struct page_region) * vec_size);
+	vec2 = malloc(sizeof(struct page_region) * vec_size);
+
+	/* 1. all new pages must be not be written (dirty) */
+	written = pagemap_ioctl(mem, mem_size, vec, 1, PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC,
+				vec_size - 2, PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN);
+	if (written < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", written, errno, strerror(errno));
+
+	ksft_test_result(written == 0, "%s all new pages must not be written (dirty)\n", prefix);
+
+	/* 2. all pages must be written */
+	memset(mem, -1, mem_size);
+
+	written = pagemap_ioctl(mem, mem_size, vec, 1, 0, 0, PAGE_IS_WRITTEN, 0, 0,
+			      PAGE_IS_WRITTEN);
+	if (written < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", written, errno, strerror(errno));
+
+	ksft_test_result(written == 1 && LEN(vec[0]) == mem_size/page_size,
+			 "%s all pages must be written (dirty)\n", prefix);
+
+	/* 3. all pages dirty other than first and the last one */
+	written = pagemap_ioctl(mem, mem_size, vec, 1, PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC,
+				0, PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN);
+	if (written < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", written, errno, strerror(errno));
+
+	memset(mem + page_size, 0, mem_size - (2 * page_size));
+
+	written = pagemap_ioctl(mem, mem_size, vec, 1, PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC,
+				0, PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN);
+	if (written < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", written, errno, strerror(errno));
+
+	ksft_test_result(written == 1 && LEN(vec[0]) >= vec_size - 2 && LEN(vec[0]) <= vec_size,
+			 "%s all pages dirty other than first and the last one\n", prefix);
+
+	written = pagemap_ioctl(mem, mem_size, vec, 1, 0, 0,
+				PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN);
+	if (written < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", written, errno, strerror(errno));
+
+	ksft_test_result(written == 0,
+			 "%s PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC\n", prefix);
+
+	/* 4. only middle page dirty */
+	written = pagemap_ioctl(mem, mem_size, vec, 1, PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC,
+				0, PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN);
+	if (written < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", written, errno, strerror(errno));
+
+	mem[vec_size/2 * page_size]++;
+
+	written = pagemap_ioctl(mem, mem_size, vec, vec_size, 0, 0, PAGE_IS_WRITTEN,
+				0, 0, PAGE_IS_WRITTEN);
+	if (written < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", written, errno, strerror(errno));
+
+	ksft_test_result(written == 1 && LEN(vec[0]) >= 1,
+			 "%s only middle page dirty\n", prefix);
+
+	/* 5. only two middle pages dirty and walk over only middle pages */
+	written = pagemap_ioctl(mem, mem_size, vec, 1, PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC,
+				0, PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN | PAGE_IS_HUGE);
+	if (written < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", written, errno, strerror(errno));
+
+	mem[vec_size/2 * page_size]++;
+	mem[(vec_size/2 + 1) * page_size]++;
+
+	written = pagemap_ioctl(&mem[vec_size/2 * page_size], 2 * page_size, vec, 1, 0,
+				0, PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN | PAGE_IS_HUGE);
+	if (written < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", written, errno, strerror(errno));
+
+	ksft_test_result(written == 1 && vec[0].start == (uintptr_t)(&mem[vec_size/2 * page_size])
+			 && LEN(vec[0]) == 2,
+			 "%s only two middle pages dirty\n", prefix);
+
+	free(vec);
+	free(vec2);
+	return 0;
+}
+
+void *gethugepage(int map_size)
+{
+	int ret;
+	char *map;
+
+	map = memalign(hpage_size, map_size);
+	if (!map)
+		ksft_exit_fail_msg("memalign failed %d %s\n", errno, strerror(errno));
+
+	ret = madvise(map, map_size, MADV_HUGEPAGE);
+	if (ret)
+		return NULL;
+
+	memset(map, 0, map_size);
+
+	return map;
+}
+
+int hpage_unit_tests(void)
+{
+	char *map;
+	int ret, ret2;
+	size_t num_pages = 10;
+	int map_size = hpage_size * num_pages;
+	int vec_size = map_size/page_size;
+	struct page_region *vec, *vec2;
+
+	vec = malloc(sizeof(struct page_region) * vec_size);
+	vec2 = malloc(sizeof(struct page_region) * vec_size);
+	if (!vec || !vec2)
+		ksft_exit_fail_msg("malloc failed\n");
+
+	map = gethugepage(map_size);
+	if (map) {
+		wp_init(map, map_size);
+		wp_addr_range(map, map_size);
+
+		/* 1. all new huge page must not be written (dirty) */
+		ret = pagemap_ioctl(map, map_size, vec, vec_size,
+				    PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC, 0,
+				    PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN);
+		if (ret < 0)
+			ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+
+		ksft_test_result(ret == 0, "%s all new huge page must not be written (dirty)\n",
+				 __func__);
+
+		/* 2. all the huge page must not be written */
+		ret = pagemap_ioctl(map, map_size, vec, vec_size, 0, 0,
+				    PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN);
+		if (ret < 0)
+			ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+
+		ksft_test_result(ret == 0, "%s all the huge page must not be written\n", __func__);
+
+		/* 3. all the huge page must be written and clear dirty as well */
+		memset(map, -1, map_size);
+		ret = pagemap_ioctl(map, map_size, vec, vec_size,
+				    PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC,
+				    0, PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN);
+		if (ret < 0)
+			ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+
+		ksft_test_result(ret == 1 && vec[0].start == (uintptr_t)map &&
+				 LEN(vec[0]) == vec_size && vec[0].categories == PAGE_IS_WRITTEN,
+				 "%s all the huge page must be written and clear\n", __func__);
+
+		/* 4. only middle page written */
+		wp_free(map, map_size);
+		free(map);
+		map = gethugepage(map_size);
+		wp_init(map, map_size);
+		wp_addr_range(map, map_size);
+		map[vec_size/2 * page_size]++;
+
+		ret = pagemap_ioctl(map, map_size, vec, vec_size, 0, 0,
+				    PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN);
+		if (ret < 0)
+			ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+
+		ksft_test_result(ret == 1 && LEN(vec[0]) > 0,
+				 "%s only middle page written\n", __func__);
+
+		wp_free(map, map_size);
+		free(map);
+	} else {
+		ksft_test_result_skip("%s all new huge page must be written\n", __func__);
+		ksft_test_result_skip("%s all the huge page must not be written\n", __func__);
+		ksft_test_result_skip("%s all the huge page must be written and clear\n", __func__);
+		ksft_test_result_skip("%s only middle page written\n", __func__);
+	}
+
+	/* 5. clear first half of huge page */
+	map = gethugepage(map_size);
+	if (map) {
+		wp_init(map, map_size);
+		wp_addr_range(map, map_size);
+
+		memset(map, 0, map_size);
+
+		wp_addr_range(map, map_size/2);
+
+		ret = pagemap_ioctl(map, map_size, vec, vec_size, 0, 0,
+				    PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN);
+		if (ret < 0)
+			ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+
+		ksft_test_result(ret == 1 && LEN(vec[0]) == vec_size/2 &&
+				 vec[0].start == (uintptr_t)(map + map_size/2),
+				 "%s clear first half of huge page\n", __func__);
+		wp_free(map, map_size);
+		free(map);
+	} else {
+		ksft_test_result_skip("%s clear first half of huge page\n", __func__);
+	}
+
+	/* 6. clear first half of huge page with limited buffer */
+	map = gethugepage(map_size);
+	if (map) {
+		wp_init(map, map_size);
+		wp_addr_range(map, map_size);
+
+		memset(map, 0, map_size);
+
+		ret = pagemap_ioctl(map, map_size, vec, vec_size,
+				    PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC,
+				    vec_size/2, PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN);
+		if (ret < 0)
+			ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+
+		ret = pagemap_ioctl(map, map_size, vec, vec_size, 0, 0,
+				    PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN);
+		if (ret < 0)
+			ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+
+		ksft_test_result(ret == 1 && LEN(vec[0]) == vec_size/2 &&
+				 vec[0].start == (uintptr_t)(map + map_size/2),
+				 "%s clear first half of huge page with limited buffer\n",
+				 __func__);
+		wp_free(map, map_size);
+		free(map);
+	} else {
+		ksft_test_result_skip("%s clear first half of huge page with limited buffer\n",
+				      __func__);
+	}
+
+	/* 7. clear second half of huge page */
+	map = gethugepage(map_size);
+	if (map) {
+		wp_init(map, map_size);
+		wp_addr_range(map, map_size);
+
+		memset(map, -1, map_size);
+
+		ret = pagemap_ioctl(map + map_size/2, map_size/2, vec, vec_size,
+				    PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC, vec_size/2,
+				    PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN);
+		if (ret < 0)
+			ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+
+		ret = pagemap_ioctl(map, map_size, vec, vec_size, 0, 0,
+				    PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN);
+		if (ret < 0)
+			ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+
+		ksft_test_result(ret == 1 && LEN(vec[0]) == vec_size/2,
+				 "%s clear second half huge page\n", __func__);
+		wp_free(map, map_size);
+		free(map);
+	} else {
+		ksft_test_result_skip("%s clear second half huge page\n", __func__);
+	}
+
+	/* 8. get half huge page */
+	map = gethugepage(map_size);
+	if (map) {
+		wp_init(map, map_size);
+		wp_addr_range(map, map_size);
+
+		memset(map, -1, map_size);
+		usleep(100);
+
+		ret = pagemap_ioctl(map, map_size, vec, 1,
+				    PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC,
+				    hpage_size/(2*page_size), PAGE_IS_WRITTEN, 0, 0,
+				    PAGE_IS_WRITTEN);
+		if (ret < 0)
+			ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+
+		ksft_test_result(ret == 1 && LEN(vec[0]) == hpage_size/(2*page_size),
+				 "%s get half huge page\n", __func__);
+
+		ret2 = pagemap_ioctl(map, map_size, vec, vec_size, 0, 0,
+				    PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN);
+		if (ret2 < 0)
+			ksft_exit_fail_msg("error %d %d %s\n", ret2, errno, strerror(errno));
+
+		ksft_test_result(ret2 == 1 && LEN(vec[0]) == (map_size - hpage_size/2)/page_size,
+				 "%s get half huge page\n", __func__);
+
+		wp_free(map, map_size);
+		free(map);
+	} else {
+		ksft_test_result_skip("%s get half huge page\n", __func__);
+		ksft_test_result_skip("%s get half huge page\n", __func__);
+	}
+
+	free(vec);
+	free(vec2);
+	return 0;
+}
+
+int unmapped_region_tests(void)
+{
+	void *start = (void *)0x10000000;
+	int written, len = 0x00040000;
+	int vec_size = len / page_size;
+	struct page_region *vec = malloc(sizeof(struct page_region) * vec_size);
+
+	/* 1. Get written pages */
+	written = pagemap_ioctl(start, len, vec, vec_size, 0, 0,
+				PAGEMAP_NON_WRITTEN_BITS, 0, 0, PAGEMAP_NON_WRITTEN_BITS);
+	if (written < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", written, errno, strerror(errno));
+
+	ksft_test_result(written >= 0, "%s Get status of pages\n", __func__);
+
+	free(vec);
+	return 0;
+}
+
+static void test_simple(void)
+{
+	int i;
+	char *map;
+	struct page_region vec;
+
+	map = aligned_alloc(page_size, page_size);
+	if (!map)
+		ksft_exit_fail_msg("aligned_alloc failed\n");
+
+	wp_init(map, page_size);
+	wp_addr_range(map, page_size);
+
+	for (i = 0 ; i < TEST_ITERATIONS; i++) {
+		if (pagemap_ioctl(map, page_size, &vec, 1, 0, 0,
+				  PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN) == 1) {
+			ksft_print_msg("written bit was 1, but should be 0 (i=%d)\n", i);
+			break;
+		}
+
+		wp_addr_range(map, page_size);
+		/* Write something to the page to get the written bit enabled on the page */
+		map[0]++;
+
+		if (pagemap_ioctl(map, page_size, &vec, 1, 0, 0,
+				  PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN) == 0) {
+			ksft_print_msg("written bit was 0, but should be 1 (i=%d)\n", i);
+			break;
+		}
+
+		wp_addr_range(map, page_size);
+	}
+	wp_free(map, page_size);
+	free(map);
+
+	ksft_test_result(i == TEST_ITERATIONS, "Test %s\n", __func__);
+}
+
+int sanity_tests(void)
+{
+	int mem_size, vec_size, ret, fd, i, buf_size;
+	struct page_region *vec;
+	char *mem, *fmem;
+	struct stat sbuf;
+	char *tmp_buf;
+
+	/* 1. wrong operation */
+	mem_size = 10 * page_size;
+	vec_size = mem_size / page_size;
+
+	vec = malloc(sizeof(struct page_region) * vec_size);
+	mem = mmap(NULL, mem_size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0);
+	if (mem == MAP_FAILED || vec == MAP_FAILED)
+		ksft_exit_fail_msg("error nomem\n");
+
+	wp_init(mem, mem_size);
+	wp_addr_range(mem, mem_size);
+
+	ksft_test_result(pagemap_ioctl(mem, mem_size, vec, vec_size,
+				       PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC,
+				       0, PAGEMAP_BITS_ALL, 0, 0, PAGEMAP_BITS_ALL) >= 0,
+			 "%s WP op can be specified with !PAGE_IS_WRITTEN\n", __func__);
+	ksft_test_result(pagemap_ioctl(mem, mem_size, vec, vec_size, 0, 0,
+				       PAGEMAP_BITS_ALL, 0, 0, PAGEMAP_BITS_ALL) >= 0,
+			 "%s required_mask specified\n", __func__);
+	ksft_test_result(pagemap_ioctl(mem, mem_size, vec, vec_size, 0, 0,
+				       0, PAGEMAP_BITS_ALL, 0, PAGEMAP_BITS_ALL) >= 0,
+			 "%s anyof_mask specified\n", __func__);
+	ksft_test_result(pagemap_ioctl(mem, mem_size, vec, vec_size, 0, 0,
+				       0, 0, PAGEMAP_BITS_ALL, PAGEMAP_BITS_ALL) >= 0,
+			 "%s excluded_mask specified\n", __func__);
+	ksft_test_result(pagemap_ioctl(mem, mem_size, vec, vec_size, 0, 0,
+				       PAGEMAP_BITS_ALL, PAGEMAP_BITS_ALL, 0,
+				       PAGEMAP_BITS_ALL) >= 0,
+			 "%s required_mask and anyof_mask specified\n", __func__);
+	wp_free(mem, mem_size);
+	munmap(mem, mem_size);
+
+	/* 2. Get sd and present pages with anyof_mask */
+	mem = mmap(NULL, mem_size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0);
+	if (mem == MAP_FAILED)
+		ksft_exit_fail_msg("error nomem\n");
+	wp_init(mem, mem_size);
+	wp_addr_range(mem, mem_size);
+
+	memset(mem, 0, mem_size);
+
+	ret = pagemap_ioctl(mem, mem_size, vec, vec_size, 0, 0,
+			    0, PAGEMAP_BITS_ALL, 0, PAGEMAP_BITS_ALL);
+	ksft_test_result(ret >= 0 && vec[0].start == (uintptr_t)mem && LEN(vec[0]) == vec_size &&
+			 (vec[0].categories & (PAGE_IS_WRITTEN | PAGE_IS_PRESENT)) ==
+			 (PAGE_IS_WRITTEN | PAGE_IS_PRESENT),
+			 "%s Get sd and present pages with anyof_mask\n", __func__);
+
+	/* 3. Get sd and present pages with required_mask */
+	ret = pagemap_ioctl(mem, mem_size, vec, vec_size, 0, 0,
+			    PAGEMAP_BITS_ALL, 0, 0, PAGEMAP_BITS_ALL);
+	ksft_test_result(ret >= 0 && vec[0].start == (uintptr_t)mem && LEN(vec[0]) == vec_size &&
+			 (vec[0].categories & (PAGE_IS_WRITTEN | PAGE_IS_PRESENT)) ==
+			 (PAGE_IS_WRITTEN | PAGE_IS_PRESENT),
+			 "%s Get all the pages with required_mask\n", __func__);
+
+	/* 4. Get sd and present pages with required_mask and anyof_mask */
+	ret = pagemap_ioctl(mem, mem_size, vec, vec_size, 0, 0,
+			    PAGE_IS_WRITTEN, PAGE_IS_PRESENT, 0, PAGEMAP_BITS_ALL);
+	ksft_test_result(ret >= 0 && vec[0].start == (uintptr_t)mem && LEN(vec[0]) == vec_size &&
+			 (vec[0].categories & (PAGE_IS_WRITTEN | PAGE_IS_PRESENT)) ==
+			 (PAGE_IS_WRITTEN | PAGE_IS_PRESENT),
+			 "%s Get sd and present pages with required_mask and anyof_mask\n",
+			 __func__);
+
+	/* 5. Don't get sd pages */
+	ret = pagemap_ioctl(mem, mem_size, vec, vec_size, 0, 0,
+			    PAGE_IS_WRITTEN, 0, PAGE_IS_WRITTEN, PAGEMAP_BITS_ALL);
+	ksft_test_result(ret == 0, "%s Don't get sd pages\n", __func__);
+
+	/* 6. Don't get present pages */
+	ret = pagemap_ioctl(mem, mem_size, vec, vec_size, 0, 0,
+			    PAGE_IS_PRESENT, 0, PAGE_IS_PRESENT, PAGEMAP_BITS_ALL);
+	ksft_test_result(ret == 0, "%s Don't get present pages\n", __func__);
+
+	wp_free(mem, mem_size);
+	munmap(mem, mem_size);
+
+	/* 8. Find written present pages with return mask */
+	mem = mmap(NULL, mem_size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0);
+	if (mem == MAP_FAILED)
+		ksft_exit_fail_msg("error nomem\n");
+	wp_init(mem, mem_size);
+	wp_addr_range(mem, mem_size);
+
+	memset(mem, 0, mem_size);
+
+	ret = pagemap_ioctl(mem, mem_size, vec, vec_size,
+			    PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC, 0,
+			    0, PAGEMAP_BITS_ALL, 0, PAGE_IS_WRITTEN);
+	ksft_test_result(ret >= 0 && vec[0].start == (uintptr_t)mem && LEN(vec[0]) == vec_size &&
+			 vec[0].categories == PAGE_IS_WRITTEN,
+			 "%s Find written present pages with return mask\n", __func__);
+	wp_free(mem, mem_size);
+	munmap(mem, mem_size);
+
+	/* 9. Memory mapped file */
+	fd = open(__FILE__, O_RDONLY);
+	if (fd < 0)
+		ksft_exit_fail_msg("%s Memory mapped file\n");
+
+	ret = stat(__FILE__, &sbuf);
+	if (ret < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+
+	fmem = mmap(NULL, sbuf.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
+	if (fmem == MAP_FAILED)
+		ksft_exit_fail_msg("error nomem %ld %s\n", errno, strerror(errno));
+
+	tmp_buf = malloc(sbuf.st_size);
+	memcpy(tmp_buf, fmem, sbuf.st_size);
+
+	ret = pagemap_ioctl(fmem, sbuf.st_size, vec, vec_size, 0, 0,
+			    0, PAGEMAP_NON_WRITTEN_BITS, 0, PAGEMAP_NON_WRITTEN_BITS);
+
+	ksft_test_result(ret >= 0 && vec[0].start == (uintptr_t)fmem &&
+			 LEN(vec[0]) == ceilf((float)sbuf.st_size/page_size) &&
+			 (vec[0].categories & PAGE_IS_FILE),
+			 "%s Memory mapped file\n", __func__);
+
+	munmap(fmem, sbuf.st_size);
+	close(fd);
+
+	/* 10. Create and read/write to a memory mapped file */
+	buf_size = page_size * 10;
+
+	fd = open(__FILE__".tmp2", O_RDWR | O_CREAT, 0666);
+	if (fd < 0)
+		ksft_exit_fail_msg("Read/write to memory: %s\n",
+				   strerror(errno));
+
+	for (i = 0; i < buf_size; i++)
+		if (write(fd, "c", 1) < 0)
+			ksft_exit_fail_msg("Create and read/write to a memory mapped file\n");
+
+	fmem = mmap(NULL, buf_size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
+	if (fmem == MAP_FAILED)
+		ksft_exit_fail_msg("error nomem %ld %s\n", errno, strerror(errno));
+
+	wp_init(fmem, buf_size);
+	wp_addr_range(fmem, buf_size);
+
+	for (i = 0; i < buf_size; i++)
+		fmem[i] = 'z';
+
+	msync(fmem, buf_size, MS_SYNC);
+
+	ret = pagemap_ioctl(fmem, buf_size, vec, vec_size, 0, 0,
+			    PAGE_IS_WRITTEN, PAGE_IS_PRESENT | PAGE_IS_SWAPPED | PAGE_IS_FILE, 0,
+			    PAGEMAP_BITS_ALL);
+
+	ksft_test_result(ret >= 0 && vec[0].start == (uintptr_t)fmem &&
+			 LEN(vec[0]) == (buf_size/page_size) &&
+			 (vec[0].categories & PAGE_IS_WRITTEN),
+			 "%s Read/write to memory\n", __func__);
+
+	wp_free(fmem, buf_size);
+	munmap(fmem, buf_size);
+	close(fd);
+
+	free(vec);
+	return 0;
+}
+
+int mprotect_tests(void)
+{
+	int ret;
+	char *mem, *mem2;
+	struct page_region vec;
+	int pagemap_fd = open("/proc/self/pagemap", O_RDONLY);
+
+	if (pagemap_fd < 0) {
+		fprintf(stderr, "open() failed\n");
+		exit(1);
+	}
+
+	/* 1. Map two pages */
+	mem = mmap(0, 2 * page_size, PROT_READ|PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0);
+	if (mem == MAP_FAILED)
+		ksft_exit_fail_msg("error nomem\n");
+	wp_init(mem, 2 * page_size);
+	wp_addr_range(mem, 2 * page_size);
+
+	/* Populate both pages. */
+	memset(mem, 1, 2 * page_size);
+
+	ret = pagemap_ioctl(mem, 2 * page_size, &vec, 1, 0, 0, PAGE_IS_WRITTEN,
+			    0, 0, PAGE_IS_WRITTEN);
+	if (ret < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+
+	ksft_test_result(ret == 1 && LEN(vec) == 2, "%s Both pages written\n", __func__);
+
+	/* 2. Start tracking */
+	wp_addr_range(mem, 2 * page_size);
+
+	ksft_test_result(pagemap_ioctl(mem, 2 * page_size, &vec, 1, 0, 0,
+				       PAGE_IS_WRITTEN, 0, 0, PAGE_IS_WRITTEN) == 0,
+			 "%s Both pages are not written (dirty)\n", __func__);
+
+	/* 3. Remap the second page */
+	mem2 = mmap(mem + page_size, page_size, PROT_READ|PROT_WRITE,
+		    MAP_PRIVATE|MAP_ANON|MAP_FIXED, -1, 0);
+	if (mem2 == MAP_FAILED)
+		ksft_exit_fail_msg("error nomem\n");
+	wp_init(mem2, page_size);
+	wp_addr_range(mem2, page_size);
+
+	/* Protect + unprotect. */
+	mprotect(mem, page_size, PROT_NONE);
+	mprotect(mem, 2 * page_size, PROT_READ);
+	mprotect(mem, 2 * page_size, PROT_READ|PROT_WRITE);
+
+	/* Modify both pages. */
+	memset(mem, 2, 2 * page_size);
+
+	/* Protect + unprotect. */
+	mprotect(mem, page_size, PROT_NONE);
+	mprotect(mem, page_size, PROT_READ);
+	mprotect(mem, page_size, PROT_READ|PROT_WRITE);
+
+	ret = pagemap_ioctl(mem, 2 * page_size, &vec, 1, 0, 0, PAGE_IS_WRITTEN,
+			    0, 0, PAGE_IS_WRITTEN);
+	if (ret < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+
+	ksft_test_result(ret == 1 && LEN(vec) == 2,
+			 "%s Both pages written after remap and mprotect\n", __func__);
+
+	/* 4. Clear and make the pages written */
+	wp_addr_range(mem, 2 * page_size);
+
+	memset(mem, 'A', 2 * page_size);
+
+	ret = pagemap_ioctl(mem, 2 * page_size, &vec, 1, 0, 0, PAGE_IS_WRITTEN,
+			    0, 0, PAGE_IS_WRITTEN);
+	if (ret < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+
+	ksft_test_result(ret == 1 && LEN(vec) == 2,
+			 "%s Clear and make the pages written\n", __func__);
+
+	wp_free(mem, 2 * page_size);
+	munmap(mem, 2 * page_size);
+	return 0;
+}
+
+/* transact test */
+static const unsigned int nthreads = 6, pages_per_thread = 32, access_per_thread = 8;
+static pthread_barrier_t start_barrier, end_barrier;
+static unsigned int extra_thread_faults;
+static unsigned int iter_count = 1000;
+static volatile int finish;
+
+static ssize_t get_dirty_pages_reset(char *mem, unsigned int count,
+				     int reset, int page_size)
+{
+	struct pm_scan_arg arg = {0};
+	struct page_region rgns[256];
+	int i, j, cnt, ret;
+
+	arg.size = sizeof(struct pm_scan_arg);
+	arg.start = (uintptr_t)mem;
+	arg.max_pages = count;
+	arg.end = (uintptr_t)(mem + count * page_size);
+	arg.vec = (uintptr_t)rgns;
+	arg.vec_len = sizeof(rgns) / sizeof(*rgns);
+	if (reset)
+		arg.flags |= PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC;
+	arg.category_mask = PAGE_IS_WRITTEN;
+	arg.return_mask = PAGE_IS_WRITTEN;
+
+	ret = ioctl(pagemap_fd, PAGEMAP_SCAN, &arg);
+	if (ret < 0)
+		ksft_exit_fail_msg("ioctl failed\n");
+
+	cnt = 0;
+	for (i = 0; i < ret; ++i) {
+		if (rgns[i].categories != PAGE_IS_WRITTEN)
+			ksft_exit_fail_msg("wrong flags\n");
+
+		for (j = 0; j < LEN(rgns[i]); ++j)
+			cnt++;
+	}
+
+	return cnt;
+}
+
+void *thread_proc(void *mem)
+{
+	int *m = mem;
+	long curr_faults, faults;
+	struct rusage r;
+	unsigned int i;
+	int ret;
+
+	if (getrusage(RUSAGE_THREAD, &r))
+		ksft_exit_fail_msg("getrusage\n");
+
+	curr_faults = r.ru_minflt;
+
+	while (!finish) {
+		ret = pthread_barrier_wait(&start_barrier);
+		if (ret && ret != PTHREAD_BARRIER_SERIAL_THREAD)
+			ksft_exit_fail_msg("pthread_barrier_wait\n");
+
+		for (i = 0; i < access_per_thread; ++i)
+			__atomic_add_fetch(m + i * (0x1000 / sizeof(*m)), 1, __ATOMIC_SEQ_CST);
+
+		ret = pthread_barrier_wait(&end_barrier);
+		if (ret && ret != PTHREAD_BARRIER_SERIAL_THREAD)
+			ksft_exit_fail_msg("pthread_barrier_wait\n");
+
+		if (getrusage(RUSAGE_THREAD, &r))
+			ksft_exit_fail_msg("getrusage\n");
+
+		faults = r.ru_minflt - curr_faults;
+		if (faults < access_per_thread)
+			ksft_exit_fail_msg("faults < access_per_thread");
+
+		__atomic_add_fetch(&extra_thread_faults, faults - access_per_thread,
+				   __ATOMIC_SEQ_CST);
+		curr_faults = r.ru_minflt;
+	}
+
+	return NULL;
+}
+
+static void transact_test(int page_size)
+{
+	unsigned int i, count, extra_pages;
+	pthread_t th;
+	char *mem;
+	int ret, c;
+
+	if (pthread_barrier_init(&start_barrier, NULL, nthreads + 1))
+		ksft_exit_fail_msg("pthread_barrier_init\n");
+
+	if (pthread_barrier_init(&end_barrier, NULL, nthreads + 1))
+		ksft_exit_fail_msg("pthread_barrier_init\n");
+
+	mem = mmap(NULL, 0x1000 * nthreads * pages_per_thread, PROT_READ | PROT_WRITE,
+		   MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
+	if (mem == MAP_FAILED)
+		ksft_exit_fail_msg("Error mmap %s.\n", strerror(errno));
+
+	wp_init(mem, 0x1000 * nthreads * pages_per_thread);
+	wp_addr_range(mem, 0x1000 * nthreads * pages_per_thread);
+
+	memset(mem, 0, 0x1000 * nthreads * pages_per_thread);
+
+	count = get_dirty_pages_reset(mem, nthreads * pages_per_thread, 1, page_size);
+	ksft_test_result(count > 0, "%s count %d\n", __func__, count);
+	count = get_dirty_pages_reset(mem, nthreads * pages_per_thread, 1, page_size);
+	ksft_test_result(count == 0, "%s count %d\n", __func__, count);
+
+	finish = 0;
+	for (i = 0; i < nthreads; ++i)
+		pthread_create(&th, NULL, thread_proc, mem + 0x1000 * i * pages_per_thread);
+
+	extra_pages = 0;
+	for (i = 0; i < iter_count; ++i) {
+		count = 0;
+
+		ret = pthread_barrier_wait(&start_barrier);
+		if (ret && ret != PTHREAD_BARRIER_SERIAL_THREAD)
+			ksft_exit_fail_msg("pthread_barrier_wait\n");
+
+		count = get_dirty_pages_reset(mem, nthreads * pages_per_thread, 1,
+					      page_size);
+
+		ret = pthread_barrier_wait(&end_barrier);
+		if (ret && ret != PTHREAD_BARRIER_SERIAL_THREAD)
+			ksft_exit_fail_msg("pthread_barrier_wait\n");
+
+		if (count > nthreads * access_per_thread)
+			ksft_exit_fail_msg("Too big count %d expected %d, iter %d\n",
+					   count, nthreads * access_per_thread, i);
+
+		c = get_dirty_pages_reset(mem, nthreads * pages_per_thread, 1, page_size);
+		count += c;
+
+		if (c > nthreads * access_per_thread) {
+			ksft_test_result_fail(" %s count > nthreads\n", __func__);
+			return;
+		}
+
+		if (count != nthreads * access_per_thread) {
+			/*
+			 * The purpose of the test is to make sure that no page updates are lost
+			 * when the page updates and read-resetting soft dirty flags are performed
+			 * in parallel. However, it is possible that the application will get the
+			 * soft dirty flags twice on the two consecutive read-resets. This seems
+			 * unavoidable as soft dirty flag is handled in software through page faults
+			 * in kernel. While the updating the flags is supposed to be synchronized
+			 * between page fault handling and read-reset, it is possible that
+			 * read-reset happens after page fault PTE update but before the application
+			 * re-executes write instruction. So read-reset gets the flag, clears write
+			 * access and application gets page fault again for the same write.
+			 */
+			if (count < nthreads * access_per_thread) {
+				ksft_test_result_fail("Lost update, iter %d, %d vs %d.\n", i, count,
+						      nthreads * access_per_thread);
+				return;
+			}
+
+			extra_pages += count - nthreads * access_per_thread;
+		}
+	}
+
+	pthread_barrier_wait(&start_barrier);
+	finish = 1;
+	pthread_barrier_wait(&end_barrier);
+
+	ksft_test_result_pass("%s Extra pages %u (%.1lf%%), extra thread faults %d.\n", __func__,
+			      extra_pages,
+			      100.0 * extra_pages / (iter_count * nthreads * access_per_thread),
+			      extra_thread_faults);
+}
+
+int main(void)
+{
+	int mem_size, shmid, buf_size, fd, i, ret;
+	char *mem, *map, *fmem;
+	struct stat sbuf;
+
+	ksft_print_header();
+	ksft_set_plan(115);
+
+	page_size = getpagesize();
+	hpage_size = read_pmd_pagesize();
+
+	pagemap_fd = open(PAGEMAP, O_RDONLY);
+	if (pagemap_fd < 0)
+		return -EINVAL;
+
+	if (init_uffd())
+		ksft_exit_fail_msg("uffd init failed\n");
+
+	/* 1. Sanity testing */
+	sanity_tests_sd();
+
+	/* 2. Normal page testing */
+	mem_size = 10 * page_size;
+	mem = mmap(NULL, mem_size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0);
+	if (mem == MAP_FAILED)
+		ksft_exit_fail_msg("error nomem\n");
+	wp_init(mem, mem_size);
+	wp_addr_range(mem, mem_size);
+
+	base_tests("Page testing:", mem, mem_size, 0);
+
+	wp_free(mem, mem_size);
+	munmap(mem, mem_size);
+
+	/* 3. Large page testing */
+	mem_size = 512 * 10 * page_size;
+	mem = mmap(NULL, mem_size, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, -1, 0);
+	if (mem == MAP_FAILED)
+		ksft_exit_fail_msg("error nomem\n");
+	wp_init(mem, mem_size);
+	wp_addr_range(mem, mem_size);
+
+	base_tests("Large Page testing:", mem, mem_size, 0);
+
+	wp_free(mem, mem_size);
+	munmap(mem, mem_size);
+
+	/* 4. Huge page testing */
+	map = gethugepage(hpage_size);
+	if (map) {
+		wp_init(map, hpage_size);
+		wp_addr_range(map, hpage_size);
+		base_tests("Huge page testing:", map, hpage_size, 0);
+		wp_free(map, hpage_size);
+		free(map);
+	} else {
+		base_tests("Huge page testing:", NULL, 0, 1);
+	}
+
+	/* 5. SHM Hugetlb page testing */
+	mem_size = 2*1024*1024;
+	mem = gethugetlb_mem(mem_size, &shmid);
+	if (mem) {
+		wp_init(mem, mem_size);
+		wp_addr_range(mem, mem_size);
+
+		base_tests("Hugetlb shmem testing:", mem, mem_size, 0);
+
+		wp_free(mem, mem_size);
+		shmctl(shmid, IPC_RMID, NULL);
+	} else {
+		base_tests("Hugetlb shmem testing:", NULL, 0, 1);
+	}
+
+	/* 6. Hugetlb page testing */
+	mem = gethugetlb_mem(mem_size, NULL);
+	if (mem) {
+		wp_init(mem, mem_size);
+		wp_addr_range(mem, mem_size);
+
+		base_tests("Hugetlb mem testing:", mem, mem_size, 0);
+
+		wp_free(mem, mem_size);
+	} else {
+		base_tests("Hugetlb mem testing:", NULL, 0, 1);
+	}
+
+	/* 7. File Hugetlb testing */
+	mem_size = 2*1024*1024;
+	fd = memfd_create("uffd-test", MFD_HUGETLB | MFD_NOEXEC_SEAL);
+	mem = mmap(NULL, mem_size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
+	if (mem) {
+		wp_init(mem, mem_size);
+		wp_addr_range(mem, mem_size);
+
+		base_tests("Hugetlb shmem testing:", mem, mem_size, 0);
+
+		wp_free(mem, mem_size);
+		shmctl(shmid, IPC_RMID, NULL);
+	} else {
+		base_tests("Hugetlb shmem testing:", NULL, 0, 1);
+	}
+	close(fd);
+
+	/* 8. File memory testing */
+	buf_size = page_size * 10;
+
+	fd = open(__FILE__".tmp0", O_RDWR | O_CREAT, 0777);
+	if (fd < 0)
+		ksft_exit_fail_msg("Create and read/write to a memory mapped file: %s\n",
+				   strerror(errno));
+
+	for (i = 0; i < buf_size; i++)
+		if (write(fd, "c", 1) < 0)
+			ksft_exit_fail_msg("Create and read/write to a memory mapped file\n");
+
+	ret = stat(__FILE__".tmp0", &sbuf);
+	if (ret < 0)
+		ksft_exit_fail_msg("error %d %d %s\n", ret, errno, strerror(errno));
+
+	fmem = mmap(NULL, sbuf.st_size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
+	if (fmem == MAP_FAILED)
+		ksft_exit_fail_msg("error nomem %ld %s\n", errno, strerror(errno));
+
+	wp_init(fmem, sbuf.st_size);
+	wp_addr_range(fmem, sbuf.st_size);
+
+	base_tests("File memory testing:", fmem, sbuf.st_size, 0);
+
+	wp_free(fmem, sbuf.st_size);
+	munmap(fmem, sbuf.st_size);
+	close(fd);
+
+	/* 9. File memory testing */
+	buf_size = page_size * 10;
+
+	fd = memfd_create(__FILE__".tmp00", MFD_NOEXEC_SEAL);
+	if (fd < 0)
+		ksft_exit_fail_msg("Create and read/write to a memory mapped file: %s\n",
+				   strerror(errno));
+
+	if (ftruncate(fd, buf_size))
+		ksft_exit_fail_msg("Error ftruncate\n");
+
+	for (i = 0; i < buf_size; i++)
+		if (write(fd, "c", 1) < 0)
+			ksft_exit_fail_msg("Create and read/write to a memory mapped file\n");
+
+	fmem = mmap(NULL, buf_size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
+	if (fmem == MAP_FAILED)
+		ksft_exit_fail_msg("error nomem %ld %s\n", errno, strerror(errno));
+
+	wp_init(fmem, buf_size);
+	wp_addr_range(fmem, buf_size);
+
+	base_tests("File anonymous memory testing:", fmem, buf_size, 0);
+
+	wp_free(fmem, buf_size);
+	munmap(fmem, buf_size);
+	close(fd);
+
+	/* 10. Huge page tests */
+	hpage_unit_tests();
+
+	/* 11. Iterative test */
+	test_simple();
+
+	/* 12. Mprotect test */
+	mprotect_tests();
+
+	/* 13. Transact test */
+	transact_test(page_size);
+
+	/* 14. Sanity testing */
+	sanity_tests();
+
+	/*15. Unmapped address test */
+	unmapped_region_tests();
+
+	/* 16. Userfaultfd tests */
+	userfaultfd_tests();
+
+	close(pagemap_fd);
+	return ksft_exit_pass();
+}
diff --git a/tools/testing/selftests/mm/run_vmtests.sh b/tools/testing/selftests/mm/run_vmtests.sh
index 3e2bc818d566f..45941ad5f6589 100755
--- a/tools/testing/selftests/mm/run_vmtests.sh
+++ b/tools/testing/selftests/mm/run_vmtests.sh
@@ -56,6 +56,8 @@  separated by spaces:
 	memory protection key tests
 - soft_dirty
 	test soft dirty page bit semantics
+- pagemap
+	test pagemap_scan IOCTL
 - cow
 	test copy-on-write semantics
 - thp
@@ -342,6 +344,8 @@  then
 	CATEGORY="soft_dirty" run_test ./soft-dirty
 fi
 
+CATEGORY="pagemap" run_test ./pagemap_ioctl
+
 # COW tests
 CATEGORY="cow" run_test ./cow