From 2039d96cb757beaf6df12651420b0415a903bc50 Mon Sep 17 00:00:00 2001
From: Axel Rasmussen <axelrasmussen@google.com>
Date: Thu, 18 Mar 2021 17:01:52 +1100
Subject: [PATCH] FROMGIT: userfaultfd/selftests: exercise minor fault handling
 shmem support

Enable test_uffdio_minor for test_type == TEST_SHMEM, and modify the test
slightly to pass in / check for the right feature flags.

Link: https://lkml.kernel.org/r/20210302000133.272579-6-axelrasmussen@google.com
Signed-off-by: Axel Rasmussen <axelrasmussen@google.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Brian Geffon <bgeffon@google.com>
Cc: Cannon Matthews <cannonmatthews@google.com>
Cc: David Rientjes <rientjes@google.com>
Cc: "Dr . David Alan Gilbert" <dgilbert@redhat.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: Joe Perches <joe@perches.com>
Cc: Lokesh Gidra <lokeshgidra@google.com>
Cc: Michel Lespinasse <walken@google.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Mina Almasry <almasrymina@google.com>
Cc: Oliver Upton <oupton@google.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Shaohua Li <shli@fb.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Wang Qing <wangqing@vivo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>

(cherry picked from commit 01d5af3a0bc027d51d729cefe3105c7054182df7
https: //git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git akpm)
Link: https://lore.kernel.org/patchwork/patch/1388148/
Signed-off-by: Lokesh Gidra <lokeshgidra@google.com>
Bug: 160737021
Bug: 169683130
Change-Id: I545c6b7058f59fe5bc21d2dd37202209253f1a92
---
 tools/testing/selftests/vm/userfaultfd.c | 19 ++++++++++++++-----
 1 file changed, 14 insertions(+), 5 deletions(-)

diff --git a/tools/testing/selftests/vm/userfaultfd.c b/tools/testing/selftests/vm/userfaultfd.c
index 470842187c89..a0276b16a7e6 100644
--- a/tools/testing/selftests/vm/userfaultfd.c
+++ b/tools/testing/selftests/vm/userfaultfd.c
@@ -1422,7 +1422,7 @@ static int userfaultfd_minor_test(void)
 	void *expected_page;
 	char c;
 	struct uffd_stats stats = { 0 };
-	uint64_t features = UFFD_FEATURE_MINOR_HUGETLBFS;
+	uint64_t req_features, features_out;
 
 	if (!test_uffdio_minor)
 		return 0;
@@ -1430,10 +1430,18 @@ static int userfaultfd_minor_test(void)
 	printf("testing minor faults: ");
 	fflush(stdout);
 
-	if (uffd_test_ctx_clear() || uffd_test_ctx_init_ext(&features))
+	if (test_type == TEST_HUGETLB)
+		req_features = UFFD_FEATURE_MINOR_HUGETLBFS;
+	else if (test_type == TEST_SHMEM)
+		req_features = UFFD_FEATURE_MINOR_SHMEM;
+	else
 		return 1;
-	/* If kernel reports the feature isn't supported, skip the test. */
-	if (!(features & UFFD_FEATURE_MINOR_HUGETLBFS)) {
+
+	features_out = req_features;
+	if (uffd_test_ctx_clear() || uffd_test_ctx_init_ext(&features_out))
+		return 1;
+	/* If kernel reports required features aren't supported, skip test. */
+	if ((features_out & req_features) != req_features) {
 		printf("skipping test due to lack of feature support\n");
 		fflush(stdout);
 		return 0;
@@ -1443,7 +1451,7 @@ static int userfaultfd_minor_test(void)
 	uffdio_register.range.len = nr_pages * page_size;
 	uffdio_register.mode = UFFDIO_REGISTER_MODE_MINOR;
 	if (ioctl(uffd, UFFDIO_REGISTER, &uffdio_register)) {
-		fprintf(stderr, "register failure\n");
+		perror("register failure");
 		exit(1);
 	}
 
@@ -1705,6 +1713,7 @@ static void set_test_type(const char *type)
 		map_shared = true;
 		test_type = TEST_SHMEM;
 		uffd_test_ops = &shmem_uffd_test_ops;
+		test_uffdio_minor = true;
 	} else {
 		fprintf(stderr, "Unknown test type: %s\n", type); exit(1);
 	}