lib/igt_kmod: New library to support driver loading/unloading and additional helpers.

lib/igt_aux: Added igt_pkill and igt_lsof helper.
lib/igt_kmod: Added load/unload kmod helpers.

v7:
- document the case where leaving stray fd from drm_open_driver()
might fail reloading the driver.
- list also current opened files from /dev/dri in case we could not
unload the driver.
- convert igt_info to igt_warn (Chris Wilson)
- added KMOD_|PROCPS CFLAGS (Chris Wilson)

v6:
- include latest modifications from tests/drv_module_reload:
display all loaded modules and list information about opened
files by processes (Petri Latvala)

v5:
- added igt_i915_driver_{load/unload}.
- added kick_snd_hda_intel() to match current
tests/drv_module_reload_basic and integrated into
igt_i915_driver_load/unload.
- added gtk-doc section for lib/igt_kmod

v4:
- decided to split libkmod helpers into their own file as there's
another user lib/igt_gvt or tests/gvt_basic.
- fixed some gtk-doc documentation.

v3:
- return -errno (igt_pkill()) in case of failure (Cris Wilson)
- return bool for igt_kmod_is_loaded(), replaced strncasecmp with strncmp
(Chris Wilson)

v2:
- Renamed libkmod helpers (Chris Wilson)
- Removed SIGTERM/SIGKILL case where we repeatedly tried to terminate the
process: just call kill(2) once (Chris Wilson)
- Removed redundant check in igt_kmod_unload(), igt_module_in_use() (Chris
Wilson)
- Pass flags to igt_kmod_unload() from the caller (Chris Wilson)
- Removed useless function igt_kill() which acts just as kill(2) (Chris
Wilson)

Signed-off-by: Marius Vlad <marius.c.vlad@intel.com>

1 files changed, 328 insertions, 0 deletions

diff --git a/lib/igt_kmod.c b/lib/igt_kmod.c
new file mode 100644
index 00000000..9fb66919
--- /dev/null
+++ b/lib/igt_kmod.c
@@ -0,0 +1,328 @@
+/*
+ * Copyright © 2016 Intel Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include "igt.h"
+#include "igt_core.h"
+#include "igt_sysfs.h"
+#include "igt_kmod.h"
+
+#include <signal.h>
+
+/**
+ * SECTION:igt_kmod
+ * @short_description: Wrappers around libkmod for module loading/unloading
+ * @title: kmod
+ * @include: igt.h
+ *
+ * This library provides helpers to load/unload module driver.
+ *
+ * Note on loading/reloading:
+ *
+ * Loading/unload/reloading the driver requires that resources to /dev/dri to
+ * be released (closed). A potential mistake would be to submit commands to the
+ * GPU by having a fd returned by @drm_open_driver, which is closed by atexit
+ * signal handler so reloading/unloading the driver will fail if performed
+ * afterwards. One possible solution to this issue is to use
+ * @__drm_open_driver() or use @igt_set_module_param() to set module parameters
+ * dynamically.
+ */
+
+
+/**
+ * igt_kmod_is_loaded:
+ * @mod_name: The name of the module.
+ *
+ * Returns: True in case the module has been found or false otherwise.
+ *
+ * Function to check the existance of module @mod_name in list of loaded kernel
+ * modules.
+ *
+ */
+bool
+igt_kmod_is_loaded(const char *mod_name)
+{
+	struct kmod_list *mod, *list;
+	struct kmod_ctx *ctx;
+	bool ret = false;
+
+	ctx = kmod_new(NULL, NULL);
+	igt_assert(ctx != NULL);
+
+	if (kmod_module_new_from_loaded(ctx, &list) < 0) {
+		goto out;
+	}
+
+	kmod_list_foreach(mod, list) {
+		struct kmod_module *kmod = kmod_module_get_module(mod);
+		const char *kmod_name = kmod_module_get_name(kmod);
+
+		if (!strncmp(kmod_name, mod_name, strlen(kmod_name))) {
+			kmod_module_unref(kmod);
+			ret = true;
+			break;
+		}
+		kmod_module_unref(kmod);
+	}
+	kmod_module_unref_list(list);
+out:
+	kmod_unref(ctx);
+
+	return ret;
+}
+
+/**
+ * igt_kmod_load:
+ * @mod_name: The name of the module
+ * @opts: Parameters for the module. NULL in case no parameters
+ * are to be passed, or a '\0' terminated string otherwise.
+ *
+ * Returns: 0 in case of success or -errno in case the module could not
+ * be loaded.
+ *
+ * This function loads a kernel module using the name specified in @mod_name.
+ *
+ * @Note: This functions doesn't automatically resolve other module
+ * dependencies so make make sure you load the dependencies module(s) before
+ * this one.
+ */
+int
+igt_kmod_load(const char *mod_name, const char *opts)
+{
+	struct kmod_ctx *ctx;
+	struct kmod_module *kmod;
+	int err = 0;
+
+	ctx = kmod_new(NULL, NULL);
+	igt_assert(ctx != NULL);
+
+	err = kmod_module_new_from_name(ctx, mod_name, &kmod);
+	if (err < 0) {
+		goto out;
+	}
+
+	err = kmod_module_insert_module(kmod, 0, opts);
+	if (err < 0) {
+		switch (err) {
+		case -EEXIST:
+			igt_debug("Module %s already inserted\n",
+				 kmod_module_get_name(kmod));
+			break;
+		case -ENOENT:
+			igt_debug("Unknown symbol in module %s or "
+				 "unknown parameter\n",
+				 kmod_module_get_name(kmod));
+			break;
+		default:
+			igt_debug("Could not insert %s (%s)\n",
+				 kmod_module_get_name(kmod), strerror(-err));
+			break;
+		}
+	}
+out:
+	kmod_module_unref(kmod);
+	kmod_unref(ctx);
+
+	return -err ? err < 0 : err;
+}
+
+
+/**
+ * igt_kmod_unload:
+ * @mod_name: Module name.
+ * @flags: flags are passed directly to libkmod and can be:
+ * KMOD_REMOVE_FORCE or KMOD_REMOVE_NOWAIT.
+ *
+ * Returns: 0 in case of success or -errno otherwise.
+ *
+ * Removes the module @mod_name.
+ *
+ */
+int
+igt_kmod_unload(const char *mod_name, unsigned int flags)
+{
+	struct kmod_ctx *ctx;
+	struct kmod_module *kmod;
+	int err = 0;
+
+	ctx = kmod_new(NULL, NULL);
+	igt_assert(ctx != NULL);
+
+	err = kmod_module_new_from_name(ctx, mod_name, &kmod);
+	if (err < 0) {
+		igt_debug("Could not use module %s (%s)\n", mod_name,
+				strerror(-err));
+		goto out;
+	}
+
+	err = kmod_module_remove_module(kmod, flags);
+	if (err < 0) {
+		igt_debug("Could not remove module %s (%s)\n", mod_name,
+				strerror(-err));
+	}
+
+out:
+	kmod_module_unref(kmod);
+	kmod_unref(ctx);
+
+	return -err ? err < 0 : err;
+}
+
+/**
+ *
+ * igt_kmod_list_loaded: List all modules currently loaded.
+ *
+ */
+void
+igt_kmod_list_loaded(void)
+{
+	struct kmod_list *module, *list;
+	struct kmod_ctx *ctx;
+
+	ctx = kmod_new(NULL, NULL);
+	igt_assert(ctx != NULL);
+
+	if (kmod_module_new_from_loaded(ctx, &list) < 0) {
+		kmod_unref(ctx);
+		return;
+	}
+
+	igt_info("Module\t\t      Used by\n");
+
+	kmod_list_foreach(module, list) {
+		struct kmod_module *kmod = kmod_module_get_module(module);
+		struct kmod_list *module_deps, *module_deps_list;
+
+		igt_info("%-24s", kmod_module_get_name(kmod));
+		module_deps_list = kmod_module_get_holders(kmod);
+		if (module_deps_list) {
+
+			kmod_list_foreach(module_deps, module_deps_list) {
+				struct kmod_module *kmod_dep;
+
+				kmod_dep = kmod_module_get_module(module_deps);
+				igt_info("%s",
+					kmod_module_get_name(kmod_dep));
+
+				if (kmod_list_next(module_deps_list, module_deps))
+					igt_info(",");
+
+				kmod_module_unref(kmod_dep);
+			}
+		}
+		kmod_module_unref_list(module_deps_list);
+
+		igt_info("\n");
+		kmod_module_unref(kmod);
+	}
+
+	kmod_module_unref_list(list);
+	kmod_unref(ctx);
+}
+
+/**
+ * igt_i915_driver_load:
+ * @opts: options to pass to i915 driver
+ *
+ * Loads the i915 driver and its dependencies.
+ *
+ */
+int
+igt_i915_driver_load(const char *opts)
+{
+	if (opts)
+		igt_info("Reloading i915 with %s\n\n", opts);
+
+	/* we do not have automatic loading of dependencies */
+	igt_kmod_load("drm", NULL);
+	igt_kmod_load("drm_kms_helper", NULL);
+
+	if (igt_kmod_load("i915", opts)) {
+		igt_warn("Could not load i915\n");
+		return IGT_EXIT_FAILURE;
+	}
+
+	kick_fbcon(true);
+	igt_kmod_load("snd_hda_intel", NULL);
+
+	return IGT_EXIT_SUCCESS;
+}
+
+/**
+ * igt_i915_driver_unload:
+ *
+ * Unloads the i915 driver and its dependencies.
+ *
+ */
+int
+igt_i915_driver_unload(void)
+{
+	/* unbind vt */
+	kick_fbcon(false);
+
+	if (igt_kmod_is_loaded("snd_hda_intel")) {
+		igt_terminate_process(SIGTERM, "alsactl");
+
+		/* unbind snd_hda_intel */
+		kick_snd_hda_intel();
+
+		if (igt_kmod_unload("snd_hda_intel", 0)) {
+			igt_warn("Could not unload snd_hda_intel\n");
+			igt_kmod_list_loaded();
+			igt_lsof("/dev/snd");
+			return IGT_EXIT_FAILURE;
+		}
+	}
+
+	/* gen5 */
+	if (igt_kmod_is_loaded("intel_ips")) {
+		igt_kmod_unload("intel_ips", 0);
+	}
+
+	if (igt_kmod_is_loaded("i915")) {
+		if (igt_kmod_unload("i915", 0)) {
+			igt_warn("Could not unload i915\n");
+			igt_kmod_list_loaded();
+			igt_lsof("/dev/dri");
+			return IGT_EXIT_SKIP;
+		} else {
+			igt_info("i915.ko has been unloaded!\n");
+		}
+	}
+
+	if (igt_kmod_is_loaded("intel-gtt")) {
+		igt_kmod_unload("intel-gtt", 0);
+	}
+
+	igt_kmod_unload("drm_kms_helper", 0);
+	igt_kmod_unload("drm", 0);
+
+	if (igt_kmod_is_loaded("i915")) {
+		igt_warn("i915.ko still loaded!\n");
+		return IGT_EXIT_FAILURE;
+	} else {
+		igt_info("module successfully unloaded\n");
+	}
+
+
+	return IGT_EXIT_SUCCESS;
+}