[LTP] [PATCH v3] testcases/kernel/device-drivers/nvme: Add NVMe device discovery test
priyama2@linux.ibm.com
priyama2@linux.ibm.com
Fri May 1 17:14:20 CEST 2026
From: priyama2 <priyama2@linux.ibm.com>
This test fills a gap in NVMe test coverage by validating basic device
enumeration and driver binding, which are fundamental prerequisites for
any NVMe functionality testing.
The test verifies:
- Detection of NVMe controllers in /dev
- Enumeration of namespaces for detected controllers
- PCI enumeration (class code 0x010802)
- NVMe driver binding
Changes in v3:
- Fix subject prefix to match directory path
- Update copyright year to 2026
- Add nvme to SUBDIRS in testcases/kernel/device-drivers/Makefile
- Reset static variables at start of run() for -i support
- Remove .needs_root (all operations are world-readable)
- Use SAFE_FOPEN/SAFE_FCLOSE for PCI class file access
- Use SAFE_READLINK for driver symlink reading
- Add .gitignore entry for nvme01 binary
- Add runtest/device-drivers entry for nvme01
- Fix author field to use priyama2
Changes in v2:
- Use LTP buildsystem instead of standalone Makefile
- Remove README file (use doc comments instead)
- Add proper LTP documentation comment format
- Use SAFE_OPENDIR() and SAFE_CLOSEDIR() macros
- Remove obvious and redundant comments
- Code cleanup and style improvements
Signed-off-by: priyama2 <priyama2@linux.ibm.com>
---
runtest/device-drivers | 1 +
testcases/kernel/device-drivers/Makefile | 1 +
.../kernel/device-drivers/nvme/.gitignore | 1 +
testcases/kernel/device-drivers/nvme/Makefile | 7 +
testcases/kernel/device-drivers/nvme/nvme01.c | 205 ++++++++++++++++++
5 files changed, 215 insertions(+)
create mode 100644 runtest/device-drivers
create mode 100644 testcases/kernel/device-drivers/nvme/.gitignore
create mode 100644 testcases/kernel/device-drivers/nvme/Makefile
create mode 100644 testcases/kernel/device-drivers/nvme/nvme01.c
diff --git a/runtest/device-drivers b/runtest/device-drivers
new file mode 100644
index 000000000..a7295584e
--- /dev/null
+++ b/runtest/device-drivers
@@ -0,0 +1 @@
+nvme01 nvme01
diff --git a/testcases/kernel/device-drivers/Makefile b/testcases/kernel/device-drivers/Makefile
index 229a50683..664f4cd18 100644
--- a/testcases/kernel/device-drivers/Makefile
+++ b/testcases/kernel/device-drivers/Makefile
@@ -9,6 +9,7 @@ SUBDIRS := acpi \
block \
cpufreq \
locking \
+ nvme \
pci \
rcu \
rtc \
diff --git a/testcases/kernel/device-drivers/nvme/.gitignore b/testcases/kernel/device-drivers/nvme/.gitignore
new file mode 100644
index 000000000..c60bc210c
--- /dev/null
+++ b/testcases/kernel/device-drivers/nvme/.gitignore
@@ -0,0 +1 @@
+nvme01
diff --git a/testcases/kernel/device-drivers/nvme/Makefile b/testcases/kernel/device-drivers/nvme/Makefile
new file mode 100644
index 000000000..d47e99e6a
--- /dev/null
+++ b/testcases/kernel/device-drivers/nvme/Makefile
@@ -0,0 +1,7 @@
+# SPDX-License-Identifier: GPL-2.0-or-later
+# Copyright (c) 2024 IBM Corporation
+
+top_srcdir ?= ../../../..
+
+include $(top_srcdir)/include/mk/env_pre.mk
+include $(top_srcdir)/include/mk/generic_trunk_target.mk
diff --git a/testcases/kernel/device-drivers/nvme/nvme01.c b/testcases/kernel/device-drivers/nvme/nvme01.c
new file mode 100644
index 000000000..3c3cb92ce
--- /dev/null
+++ b/testcases/kernel/device-drivers/nvme/nvme01.c
@@ -0,0 +1,205 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (c) 2026 IBM Corporation
+ * Author: priyama2 <priyama2@linux.ibm.com>
+ */
+
+/* * [Description]
+ *
+ * Verify NVMe device discovery and identification.
+ *
+ * This test fills a gap in NVMe test coverage by validating basic device
+ * enumeration and driver binding, which are fundamental prerequisites for
+ * any NVMe functionality testing.
+ *
+ * - Detect NVMe controllers in /dev
+ * - Enumerate namespaces for detected controllers
+ * - Verify PCI enumeration (class code 0x010802)
+ * - Check NVMe driver binding
+ */
+
+#define _GNU_SOURCE
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <dirent.h>
+#include <errno.h>
+
+#include "tst_test.h"
+#include "tst_safe_stdio.h"
+
+#define NVME_DEV_PATH "/dev"
+#define NVME_SYS_PATH "/sys/class/nvme"
+#define PCI_DEVICES_PATH "/sys/bus/pci/devices"
+
+static int nvme_device_found;
+static char nvme_dev_name[256];
+
+static void test_detect_nvme_controllers(void)
+{
+ DIR *dir;
+ struct dirent *entry;
+ int found = 0;
+
+ dir = SAFE_OPENDIR(NVME_DEV_PATH);
+
+ tst_res(TINFO, "Scanning for NVMe devices in %s", NVME_DEV_PATH);
+
+ while ((entry = readdir(dir)) != NULL) {
+ if (strncmp(entry->d_name, "nvme", 4) == 0 &&
+ strlen(entry->d_name) == 5) {
+ tst_res(TINFO, "Found NVMe controller: %s", entry->d_name);
+ strncpy(nvme_dev_name, entry->d_name, sizeof(nvme_dev_name) - 1);
+ found = 1;
+ nvme_device_found = 1;
+ }
+ }
+
+ SAFE_CLOSEDIR(dir);
+
+ if (found)
+ tst_res(TPASS, "NVMe controller(s) detected successfully");
+ else
+ tst_res(TCONF, "No NVMe controllers found in system");
+}
+
+static void test_enumerate_namespaces(void)
+{
+ DIR *dir;
+ struct dirent *entry;
+ int ns_count = 0;
+ char search_pattern[32];
+
+ if (!nvme_device_found) {
+ tst_res(TCONF, "No NVMe device found, skipping namespace enumeration");
+ return;
+ }
+
+ snprintf(search_pattern, sizeof(search_pattern), "%sn", nvme_dev_name);
+
+ dir = SAFE_OPENDIR(NVME_DEV_PATH);
+
+ tst_res(TINFO, "Enumerating namespaces for %s", nvme_dev_name);
+
+ while ((entry = readdir(dir)) != NULL) {
+ if (strncmp(entry->d_name, search_pattern, strlen(search_pattern)) == 0) {
+ tst_res(TINFO, "Found namespace: %s", entry->d_name);
+ ns_count++;
+ }
+ }
+
+ SAFE_CLOSEDIR(dir);
+
+ if (ns_count > 0)
+ tst_res(TPASS, "Enumerated %d namespace(s) successfully", ns_count);
+ else
+ tst_res(TPASS, "No namespaces found for %s (device may not have namespaces configured)", nvme_dev_name);
+}
+
+static void test_verify_pci_enumeration(void)
+{
+ DIR *dir;
+ struct dirent *entry;
+ int found = 0;
+ char class_path[512];
+ FILE *fp;
+ char class_id[16];
+
+ if (!nvme_device_found) {
+ tst_res(TCONF, "No NVMe device found, skipping PCI enumeration check");
+ return;
+ }
+
+ dir = SAFE_OPENDIR(PCI_DEVICES_PATH);
+
+ tst_res(TINFO, "Checking PCI enumeration for NVMe devices");
+
+ while ((entry = readdir(dir)) != NULL) {
+ if (entry->d_name[0] == '.')
+ continue;
+
+ snprintf(class_path, sizeof(class_path), "%s/%s/class",
+ PCI_DEVICES_PATH, entry->d_name);
+
+ fp = SAFE_FOPEN(class_path, "r");
+
+ if (fgets(class_id, sizeof(class_id), fp)) {
+ if (strncmp(class_id, "0x010802", 8) == 0) {
+ tst_res(TINFO, "Found NVMe PCI device: %s (class: %s)",
+ entry->d_name, class_id);
+ found = 1;
+ }
+ }
+ SAFE_FCLOSE(fp);
+ }
+
+ SAFE_CLOSEDIR(dir);
+
+ if (found)
+ tst_res(TPASS, "NVMe device properly enumerated on PCI bus");
+ else
+ tst_res(TFAIL, "NVMe device not found on PCI bus");
+}
+
+static void test_check_driver_binding(void)
+{
+ char driver_path[512];
+ char driver_link[512];
+
+ if (!nvme_device_found) {
+ tst_res(TCONF, "No NVMe device found, skipping driver binding check");
+ return;
+ }
+
+ snprintf(driver_path, sizeof(driver_path), "%s/%s/device/driver",
+ NVME_SYS_PATH, nvme_dev_name);
+
+ SAFE_READLINK(driver_path, driver_link, sizeof(driver_link));
+
+ tst_res(TINFO, "Driver binding: %s", driver_link);
+
+ if (strstr(driver_link, "nvme") != NULL)
+ tst_res(TPASS, "NVMe driver properly bound to device");
+ else
+ tst_res(TFAIL, "Unexpected driver bound to NVMe device: %s", driver_link);
+}
+
+static void setup(void)
+{
+ if (access("/sys/module/nvme", F_OK) != 0)
+ tst_brk(TCONF, "NVMe kernel module not loaded");
+
+ tst_res(TINFO, "NVMe Device Discovery & Identification Test");
+}
+
+static void run(unsigned int n)
+{
+ /* Reset state for each iteration */
+ nvme_device_found = 0;
+ memset(nvme_dev_name, 0, sizeof(nvme_dev_name));
+
+ switch (n) {
+ case 0:
+ test_detect_nvme_controllers();
+ break;
+ case 1:
+ test_enumerate_namespaces();
+ break;
+ case 2:
+ test_verify_pci_enumeration();
+ break;
+ case 3:
+ test_check_driver_binding();
+ break;
+ }
+}
+
+static struct tst_test test = {
+ .test = run,
+ .tcnt = 4,
+ .setup = setup,
+};
--
2.52.0
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