+ selftests-mm-move-certain-uffd-routines-from-vm_utilc-to-uffd-commonc.patch added to mm-unstable branch

+ selftests-mm-move-certain-uffd-routines-from-vm_utilc-to-uffd-commonc.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: selftests/mm: move certain uffd*() routines from vm_util.c to uffd-common.c
has been added to the -mm mm-unstable branch.  Its filename is
     selftests-mm-move-certain-uffd-routines-from-vm_utilc-to-uffd-commonc.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/selftests-mm-move-certain-uffd-routines-from-vm_utilc-to-uffd-commonc.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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*** Remember to use Documentation/process/submit-checklist.rst when testing your code ***

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branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
and is updated there every 2-3 working days

------------------------------------------------------
From: John Hubbard <jhubbard@nvidia.com>
Subject: selftests/mm: move certain uffd*() routines from vm_util.c to uffd-common.c
Date: Tue, 6 Jun 2023 00:16:35 -0700

There are only three uffd*() routines that are used outside of the uffd
selftests. Leave these in vm_util.c, where they are available to any mm
selftest program:

    uffd_register()
    uffd_unregister()
    uffd_register_with_ioctls().

A few other uffd*() routines, however, are only used by the uffd-focused
tests found in uffd-stress.c and uffd-unit-tests.c. Move those routines
into uffd-common.c.

Link: https://lkml.kernel.org/r/20230606071637.267103-10-jhubbard@nvidia.com
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Acked-by: David Hildenbrand <david@redhat.com>
Tested-by: Muhammad Usama Anjum <usama.anjum@collabora.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 tools/testing/selftests/mm/uffd-common.c |   59 +++++++++++++++++++++
 tools/testing/selftests/mm/uffd-common.h |    5 +
 tools/testing/selftests/mm/vm_util.c     |   59 ---------------------
 tools/testing/selftests/mm/vm_util.h     |    4 -
 4 files changed, 64 insertions(+), 63 deletions(-)

--- a/tools/testing/selftests/mm/uffd-common.c~selftests-mm-move-certain-uffd-routines-from-vm_utilc-to-uffd-commonc
+++ a/tools/testing/selftests/mm/uffd-common.c
@@ -616,3 +616,62 @@ int copy_page(int ufd, unsigned long off
 {
 	return __copy_page(ufd, offset, false, wp);
 }
+
+int uffd_open_dev(unsigned int flags)
+{
+	int fd, uffd;
+
+	fd = open("/dev/userfaultfd", O_RDWR | O_CLOEXEC);
+	if (fd < 0)
+		return fd;
+	uffd = ioctl(fd, USERFAULTFD_IOC_NEW, flags);
+	close(fd);
+
+	return uffd;
+}
+
+int uffd_open_sys(unsigned int flags)
+{
+#ifdef __NR_userfaultfd
+	return syscall(__NR_userfaultfd, flags);
+#else
+	return -1;
+#endif
+}
+
+int uffd_open(unsigned int flags)
+{
+	int uffd = uffd_open_sys(flags);
+
+	if (uffd < 0)
+		uffd = uffd_open_dev(flags);
+
+	return uffd;
+}
+
+int uffd_get_features(uint64_t *features)
+{
+	struct uffdio_api uffdio_api = { .api = UFFD_API, .features = 0 };
+	/*
+	 * This should by default work in most kernels; the feature list
+	 * will be the same no matter what we pass in here.
+	 */
+	int fd = uffd_open(UFFD_USER_MODE_ONLY);
+
+	if (fd < 0)
+		/* Maybe the kernel is older than user-only mode? */
+		fd = uffd_open(0);
+
+	if (fd < 0)
+		return fd;
+
+	if (ioctl(fd, UFFDIO_API, &uffdio_api)) {
+		close(fd);
+		return -errno;
+	}
+
+	*features = uffdio_api.features;
+	close(fd);
+
+	return 0;
+}
--- a/tools/testing/selftests/mm/uffd-common.h~selftests-mm-move-certain-uffd-routines-from-vm_utilc-to-uffd-commonc
+++ a/tools/testing/selftests/mm/uffd-common.h
@@ -110,6 +110,11 @@ int __copy_page(int ufd, unsigned long o
 int copy_page(int ufd, unsigned long offset, bool wp);
 void *uffd_poll_thread(void *arg);
 
+int uffd_open_dev(unsigned int flags);
+int uffd_open_sys(unsigned int flags);
+int uffd_open(unsigned int flags);
+int uffd_get_features(uint64_t *features);
+
 #define TEST_ANON	1
 #define TEST_HUGETLB	2
 #define TEST_SHMEM	3
--- a/tools/testing/selftests/mm/vm_util.c~selftests-mm-move-certain-uffd-routines-from-vm_utilc-to-uffd-commonc
+++ a/tools/testing/selftests/mm/vm_util.c
@@ -269,62 +269,3 @@ int uffd_unregister(int uffd, void *addr
 
 	return ret;
 }
-
-int uffd_open_dev(unsigned int flags)
-{
-	int fd, uffd;
-
-	fd = open("/dev/userfaultfd", O_RDWR | O_CLOEXEC);
-	if (fd < 0)
-		return fd;
-	uffd = ioctl(fd, USERFAULTFD_IOC_NEW, flags);
-	close(fd);
-
-	return uffd;
-}
-
-int uffd_open_sys(unsigned int flags)
-{
-#ifdef __NR_userfaultfd
-	return syscall(__NR_userfaultfd, flags);
-#else
-	return -1;
-#endif
-}
-
-int uffd_open(unsigned int flags)
-{
-	int uffd = uffd_open_sys(flags);
-
-	if (uffd < 0)
-		uffd = uffd_open_dev(flags);
-
-	return uffd;
-}
-
-int uffd_get_features(uint64_t *features)
-{
-	struct uffdio_api uffdio_api = { .api = UFFD_API, .features = 0 };
-	/*
-	 * This should by default work in most kernels; the feature list
-	 * will be the same no matter what we pass in here.
-	 */
-	int fd = uffd_open(UFFD_USER_MODE_ONLY);
-
-	if (fd < 0)
-		/* Maybe the kernel is older than user-only mode? */
-		fd = uffd_open(0);
-
-	if (fd < 0)
-		return fd;
-
-	if (ioctl(fd, UFFDIO_API, &uffdio_api)) {
-		close(fd);
-		return -errno;
-	}
-
-	*features = uffdio_api.features;
-	close(fd);
-
-	return 0;
-}
--- a/tools/testing/selftests/mm/vm_util.h~selftests-mm-move-certain-uffd-routines-from-vm_utilc-to-uffd-commonc
+++ a/tools/testing/selftests/mm/vm_util.h
@@ -49,10 +49,6 @@ int detect_hugetlb_page_sizes(size_t siz
 int uffd_register(int uffd, void *addr, uint64_t len,
 		  bool miss, bool wp, bool minor);
 int uffd_unregister(int uffd, void *addr, uint64_t len);
-int uffd_open_dev(unsigned int flags);
-int uffd_open_sys(unsigned int flags);
-int uffd_open(unsigned int flags);
-int uffd_get_features(uint64_t *features);
 int uffd_register_with_ioctls(int uffd, void *addr, uint64_t len,
 			      bool miss, bool wp, bool minor, uint64_t *ioctls);
 
_

Patches currently in -mm which might be from jhubbard@nvidia.com are

selftests-mm-fix-uffd-stress-unused-function-warning.patch
selftests-mm-fix-unused-variable-warnings-in-hugetlb-madvisec-migrationc.patch
selftests-mm-fix-warning-expression-which-evaluates-to-zero-in-mlock2-testsc.patch
selftests-mm-fix-invocation-of-tests-that-are-run-via-shell-scripts.patch
selftests-mm-gitignore-add-mkdirty-va_high_addr_switch.patch
selftests-mm-fix-two-wformat-security-warnings-in-uffd-builds.patch
selftests-mm-fix-a-possibly-uninitialized-warning-in-pkey-x86h.patch
selftests-mm-fix-build-failures-due-to-missing-madv_collapse.patch
selftests-mm-move-certain-uffd-routines-from-vm_utilc-to-uffd-commonc.patch
documentation-kselftest-make-headers-is-a-prerequisite.patch
selftests-error-out-if-kernel-header-files-are-not-yet-built.patch
selftests-error-out-if-kernel-header-files-are-not-yet-built-fix.patch