[LTP] [PATCH] Migrating the libhugetlbfs/testcases/shm-gettest.c test

[Sachin P Bappalige]

Test Description: This testcase creates shared memory segments
backed by hugepages, writes  specific patterns to each segment,
verifies pattern and detaches a shared memory segments in a loop.

This looping test was added to verify the functionality of
large page backed shared memory segments. A segment is created,
written, verified, and detached a specified number of times.

Signed-off-by: Sachin P Bappalige <sachinpb@linux.vnet.ibm.com>
---
 runtest/hugetlb                               |  1 +
 testcases/kernel/mem/.gitignore               |  1 +
 .../kernel/mem/hugetlb/hugemmap/hugepage35.c  | 93 +++++++++++++++++++
 3 files changed, 95 insertions(+)
 create mode 100644 testcases/kernel/mem/hugetlb/hugemmap/hugepage35.c

diff --git a/runtest/hugetlb b/runtest/hugetlb
index 299c07ac9..6bebc706c 100644
--- a/runtest/hugetlb
+++ b/runtest/hugetlb
@@ -35,6 +35,7 @@ hugemmap29 hugemmap29
 hugemmap30 hugemmap30
 hugemmap31 hugemmap31
 hugemmap32 hugemmap32
+hugemmap35 hugemmap35
 hugemmap05_1 hugemmap05 -m
 hugemmap05_2 hugemmap05 -s
 hugemmap05_3 hugemmap05 -s -m
diff --git a/testcases/kernel/mem/.gitignore b/testcases/kernel/mem/.gitignore
index 7258489ed..bbc029716 100644
--- a/testcases/kernel/mem/.gitignore
+++ b/testcases/kernel/mem/.gitignore
@@ -34,6 +34,7 @@
 /hugetlb/hugemmap/hugemmap30
 /hugetlb/hugemmap/hugemmap31
 /hugetlb/hugemmap/hugemmap32
+/hugetlb/hugemmap/hugemmap35
 /hugetlb/hugeshmat/hugeshmat01
 /hugetlb/hugeshmat/hugeshmat02
 /hugetlb/hugeshmat/hugeshmat03
diff --git a/testcases/kernel/mem/hugetlb/hugemmap/hugepage35.c b/testcases/kernel/mem/hugetlb/hugemmap/hugepage35.c
new file mode 100644
index 000000000..fb603b4ef
--- /dev/null
+++ b/testcases/kernel/mem/hugetlb/hugemmap/hugepage35.c
@@ -0,0 +1,93 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2005-2006, IBM Corporation.
+ * Author: David Gibson & Adam Litke
+ */
+
+/*\
+ * [Description]
+ *
+ * Test Name: shm-gettest.c
+ *
+ * This testcase creates shared memory segments backed by hugepages, 
+ * writes specific patterns to each segment, verifies pattern,
+ * and detaches a shared memory segments in a loop. 
+ * It ensures that the hugepage backed shared memory functionalities 
+ * works correctly by validating the data written to segment.
+ */
+
+#include "hugetlb.h"
+#include "tst_safe_sysv_ipc.h"
+
+#define MNTPOINT "hugetlbfs/"
+#define NR_HUGEPAGES 4
+
+static long hpage_size;
+static unsigned int iter;
+static int shmid = -1, key = -1;
+
+static void do_shmtest(size_t size) {
+        size_t i, j;
+        char pattern;
+        char *shmaddr;
+
+        shmid = SAFE_SHMGET(key, size, SHM_HUGETLB|IPC_CREAT|SHM_R|SHM_W);
+        tst_res(TINFO, "shmid: 0x%x\n", shmid);
+
+        shmaddr = SAFE_SHMAT(shmid, 0, SHM_RND);
+        tst_res(TINFO, "shmaddr: %p\n", shmaddr);
+
+        for (i = 0; i < NR_HUGEPAGES; i++) {
+                pattern = 65 + (i % 26);
+                tst_res(TINFO, "Touching %p with %c\n",
+                                shmaddr + (i * hpage_size), pattern);
+                memset(shmaddr + (i * hpage_size), pattern, hpage_size);
+        }
+
+        for (i = 0; i < NR_HUGEPAGES; i++) {
+                pattern = 65 + (i % 26);
+                tst_res(TINFO, "Verifying %p\n", (shmaddr + (i * hpage_size)));
+                for (j = 0; j < (size_t)hpage_size; j++)
+                        if (*(shmaddr + (i * hpage_size) + j) != pattern)
+                                tst_res(TFAIL, "Verifying the segment failed."
+                                        "Got %c, expected %c",
+                                        *(shmaddr + (i * hpage_size) + j),
+                                        pattern);
+        }
+        SAFE_SHMDT((const void *)shmaddr);
+}
+
+static void run_test(void)
+{
+        int i;
+        iter = 2;
+        size_t size;
+        size = NR_HUGEPAGES * hpage_size;
+        for (i=0; i < (int)iter; i++)
+                do_shmtest(size);
+        tst_res(TPASS, "Successfully tested shared memory segment operations "
+                        "backed by hugepages");
+}
+
+static void setup(void)
+{
+        hpage_size = tst_get_hugepage_size();
+        tst_res(TINFO, "hugepage size is  %ld", hpage_size);
+}
+
+static void cleanup(void)
+{
+        if (shmid >= 0)
+                // Remove the shared memory segment
+                SAFE_SHMCTL(shmid, IPC_RMID, NULL);
+}
+
+static struct tst_test test = {
+        .needs_root = 1,
+        .mntpoint = MNTPOINT,
+        .needs_hugetlbfs = 1,
+        .setup = setup,
+        .cleanup = cleanup,
+        .test_all = run_test,
+        .hugepages = {NR_HUGEPAGES, TST_NEEDS},
+};
-- 
2.39.3