Add devices and driver

Author: IgnoreWarnings

common/include/villas/kernel/devices/device.hpp

@@ -0,0 +1,22 @@
+/* Device
+ *
+ * Author: Pascal Bauer <[email protected]>
+ *
+ * SPDX-FileCopyrightText: 2023-2024 Pascal Bauer <[email protected]>
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#pragma once
+
+#include <filesystem>
+#include <optional>
+#include <villas/kernel/devices/driver.hpp>
+
+class Device {
+public:
+  virtual std::string name() const = 0;
+  virtual std::optional<Driver> driver() const = 0;
+  virtual int iommu_group() const = 0;
+  virtual void probe() const = 0;
+  virtual std::filesystem::path get_override_path() const = 0;
+};

common/include/villas/kernel/devices/driver.hpp

@@ -0,0 +1,43 @@
+/* Driver
+ *
+ * Author: Pascal Bauer <[email protected]>
+ *
+ * SPDX-FileCopyrightText: 2023-2024 Pascal Bauer <[email protected]>
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#pragma once
+
+#include <fstream>
+#include <iostream>
+
+class Device;
+
+class Driver {
+private:
+  static constexpr char BIND_DEFAULT[] = "bind";
+  static constexpr char UNBIND_DEFAULT[] = "unbind";
+
+public:
+  const std::filesystem::path path;
+
+private:
+  const std::filesystem::path bind_path;
+  const std::filesystem::path unbind_path;
+
+public:
+  Driver(const std::filesystem::path path)
+      : Driver(path, path / std::filesystem::path(BIND_DEFAULT),
+               path / std::filesystem::path(UNBIND_DEFAULT)){};
+
+  Driver(const std::filesystem::path path,
+         const std::filesystem::path bind_path,
+         const std::filesystem::path unbind_path)
+      : path(path), bind_path(bind_path), unbind_path(unbind_path){};
+
+  std::string name() const;
+  void bind(const Device &device) const;
+  void unbind(const Device &device) const;
+  void override(const Device &device) const;
+  void attach(const Device &device) const;
+};

common/include/villas/kernel/devices/ip_device.hpp

@@ -0,0 +1,26 @@
+/* IpDevice
+ *
+ * Author: Pascal Bauer <[email protected]>
+ *
+ * SPDX-FileCopyrightText: 2023-2024 Pascal Bauer <[email protected]>
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#pragma once
+
+#include <filesystem>
+#include <villas/kernel/devices/platform_device.hpp>
+
+class IpDevice : public PlatformDevice {
+public:
+public:
+  static IpDevice from(const std::filesystem::path unsafe_path);
+  static bool is_path_valid(const std::filesystem::path unsafe_path);
+
+private:
+  IpDevice(const std::filesystem::path valid_path) : PlatformDevice(path){};
+
+public:
+  std::string ip_name() const;
+  size_t addr() const;
+};

common/include/villas/kernel/devices/platform_device.hpp

@@ -0,0 +1,72 @@
+/* Platform Device
+ *
+ * Author: Pascal Bauer <[email protected]>
+ *
+ * SPDX-FileCopyrightText: 2023-2024 Pascal Bauer <[email protected]>
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#pragma once
+
+#include <filesystem>
+#include <villas/kernel/devices/device.hpp>
+#include <villas/kernel/devices/utils.hpp>
+
+class PlatformDevice : public Device {
+private:
+  static constexpr char PROBE_DEFAULT[] = "/sys/bus/platform/drivers_probe";
+  static constexpr char OVERRIDE_DEFAULT[] = "driver_override";
+
+public:
+  const std::filesystem::path path;
+  const std::filesystem::path probe_path;
+  const std::filesystem::path override_path;
+
+public:
+  PlatformDevice(const std::filesystem::path path)
+      : PlatformDevice(path, std::filesystem::path(PROBE_DEFAULT),
+                       path / std::filesystem::path(OVERRIDE_DEFAULT)){};
+  PlatformDevice(const std::filesystem::path path,
+                 const std::filesystem::path probe_path,
+                 const std::filesystem::path override_path)
+      : path(path), probe_path(probe_path), override_path(override_path){};
+
+  std::string name() const override {
+    size_t pos = path.u8string().rfind('/');
+    return path.u8string().substr(pos + 1);
+  }
+
+  std::optional<Driver> driver() const override {
+    std::filesystem::path driver_symlink =
+        this->path / std::filesystem::path("driver");
+
+    if (!std::filesystem::is_symlink(driver_symlink))
+      return std::nullopt;
+
+    std::filesystem::path driver_path =
+        std::filesystem::canonical(driver_symlink);
+    return Driver(driver_path);
+  };
+
+  int iommu_group() const override {
+    std::filesystem::path symlink =
+        std::filesystem::path(this->path.u8string() + "/iommu_group");
+
+    std::filesystem::path link;
+    link = std::filesystem::read_symlink(symlink);
+
+    std::string delimiter = "iommu_groups/";
+    int pos = link.u8string().find(delimiter);
+    int iommu_group =
+        std::stoi(link.u8string().substr(pos + delimiter.length()));
+    return iommu_group;
+  }
+
+  void probe() const override {
+    write_to_file(this->name(), this->probe_path);
+  };
+
+  virtual std::filesystem::path get_override_path() const override {
+    return this->override_path;
+  };
+};

common/include/villas/kernel/devices/utils.hpp

@@ -0,0 +1,16 @@
+/* Utils
+ *
+ * Author: Pascal Bauer <[email protected]>
+ *
+ * SPDX-FileCopyrightText: 2023-2024 Pascal Bauer <[email protected]>
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#pragma once
+
+#include <filesystem>
+#include <string>
+#include <vector>
+
+void write_to_file(std::string data, const std::filesystem::path file);
+std::vector<std::string> read_names_in_directory(const std::string &name);

common/lib/CMakeLists.txt

@@ -15,6 +15,11 @@ add_library(villas-common SHARED
     cpuset.cpp
     dsp/pid.cpp
     hist.cpp
+    
+    kernel/devices/driver.cpp
+    kernel/devices/ip_device.cpp
+    kernel/devices/utils.cpp
+
     kernel/kernel.cpp
     kernel/rt.cpp
     list.cpp

common/lib/kernel/devices/driver.cpp

@@ -0,0 +1,35 @@
+/* Driver
+ *
+ * Author: Pascal Bauer <[email protected]>
+ *
+ * SPDX-FileCopyrightText: 2023-2024 Pascal Bauer <[email protected]>
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <villas/kernel/devices/ip_device.hpp>
+#include <villas/kernel/devices/utils.hpp>
+
+std::string Driver::name() const {
+  size_t pos = path.u8string().rfind('/');
+  return path.u8string().substr(pos + 1);
+}
+
+void Driver::bind(const Device &device) const {
+  write_to_file(device.name(), this->bind_path);
+};
+
+void Driver::unbind(const Device &device) const {
+  write_to_file(device.name(), this->unbind_path);
+};
+
+void Driver::override(const Device &device) const {
+  write_to_file(this->name(), device.get_override_path());
+};
+
+void Driver::attach(const Device &device) const {
+  if (device.driver().has_value()) {
+    device.driver().value().unbind(device);
+  }
+  this->override(device);
+  device.probe();
+};

common/lib/kernel/devices/ip_device.cpp

@@ -0,0 +1,53 @@
+/* IpDevice
+ *
+ * Author: Pascal Bauer <[email protected]>
+ *
+ * SPDX-FileCopyrightText: 2023-2024 Pascal Bauer <[email protected]>
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <filesystem>
+#include <regex>
+#include <stdexcept>
+
+#include <villas/kernel/devices/ip_device.hpp>
+
+IpDevice IpDevice::from(const std::filesystem::path unsafe_path) {
+  if (!is_path_valid(unsafe_path))
+    throw std::runtime_error(
+        "Path \"" + unsafe_path.u8string() +
+        "\" failed validation as IpDevicePath \"[adress in hex].[name]\". ");
+  return IpDevice(unsafe_path);
+}
+
+bool IpDevice::is_path_valid(const std::filesystem::path unsafe_path) {
+  // Split the string at last slash
+  int pos = unsafe_path.u8string().rfind('/');
+  std::string assumed_device_name = unsafe_path.u8string().substr(pos + 1);
+
+  // Match format of hexaddr.devicename
+  if (!std::regex_match(assumed_device_name,
+                        std::regex(R"([0-9A-Fa-f]+\..*)"))) {
+    return false;
+  }
+
+  return true;
+}
+
+std::string IpDevice::ip_name() const {
+  int pos = name().find('.');
+  return name().substr(pos + 1);
+}
+
+size_t IpDevice::addr() const {
+  size_t pos = name().find('.');
+  std::string addr_hex = name().substr(0, pos);
+
+  // convert from hex string to number
+  std::stringstream ss;
+  ss << std::hex << addr_hex;
+  size_t addr = 0;
+  ss >> addr;
+
+  return addr;
+}

common/lib/kernel/devices/utils.cpp

@@ -0,0 +1,45 @@
+/* Utils
+ *
+ * Author: Pascal Bauer <[email protected]>
+ *
+ * SPDX-FileCopyrightText: 2023-2024 Pascal Bauer <[email protected]>
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <dirent.h>
+#include <filesystem>
+#include <fstream>
+#include <iostream>
+#include <villas/kernel/devices/utils.hpp>
+#include <villas/log.hpp>
+
+void write_to_file(std::string data, const std::filesystem::path file) {
+  villas::Log::get("Filewriter")->debug("{} > {}", data, file.u8string());
+  std::ofstream outputFile(file.u8string());
+
+  if (outputFile.is_open()) {
+    // Write to file
+    outputFile << data;
+    outputFile.close();
+  } else {
+    throw std::filesystem::filesystem_error("Cannot open outputfile",
+                                            std::error_code());
+  }
+}
+
+std::vector<std::string> read_names_in_directory(const std::string &name) {
+  DIR *directory = opendir(name.c_str());
+
+  struct dirent *dp;
+  std::vector<std::string> names;
+  dp = readdir(directory);
+  while (dp != NULL) {
+    auto name = std::string(dp->d_name);
+    if (name != "." && name != "..") {
+      names.push_back(name);
+    }
+    dp = readdir(directory);
+  }
+  closedir(directory);
+  return names;
+}