uefi: Add convenient methods for &DevicePath -> PoolDevicePath

Author: seijikun

uefi/CHANGELOG.md

@@ -5,6 +5,8 @@
 - Added `proto::shell::Shell::{var(), set_var(), vars()}`
 - Added `proto::pci::root_bridge::PciRootBridgeIo::configuration()`.
 - Added `proto::pci::root_bridge::PciRootBridgeIo::enumerate()`.
+- Added `proto::device_path::DevicePath::to_pool()`.
+- Added `proto::device_path::DevicePathUtilities::duplicate_path()`.
 
 ## Changed
 - Changed ordering of `proto::pci::PciIoAddress` to (bus -> dev -> fun -> reg -> ext_reg).

uefi/src/proto/device_path/mod.rs

@@ -590,6 +590,14 @@ impl DevicePath {
         unsafe { mem::transmute(data) }
     }
 
+    /// Returns an owned pool copy of this path.
+    #[cfg(feature = "alloc")]
+    pub fn to_pool(&self) -> Result<PoolDevicePath, DevicePathUtilitiesError> {
+        open_utility_protocol()?
+            .duplicate_path(self)
+            .map_err(|_| DevicePathUtilitiesError::OutOfMemory)
+    }
+
     /// Transforms the device path to its string representation using the
     /// [`DevicePathToText`] protocol.
     #[cfg(feature = "alloc")]

uefi/src/proto/device_path/util.rs

@@ -29,6 +29,22 @@ impl DevicePathUtilities {
         unsafe { (self.0.get_device_path_size)(device_path.as_ffi_ptr().cast()) }
     }
 
+    /// Create a new device path by cloning the given `path` into newly allocated memory.
+    ///
+    /// # Arguments
+    /// - `path`: A reference to the device path to clone.
+    ///
+    /// # Returns
+    /// A [`PoolDevicePath`] instance created by cloning the given `path`.
+    pub fn duplicate_path(&self, path: &DevicePath) -> crate::Result<PoolDevicePath> {
+        unsafe {
+            let ptr = (self.0.duplicate_device_path)(path.as_ffi_ptr().cast());
+            NonNull::new(ptr.cast_mut())
+                .map(|p| PoolDevicePath(PoolAllocation::new(p.cast())))
+                .ok_or_else(|| Status::OUT_OF_RESOURCES.into())
+        }
+    }
+
     /// Creates a new device path by appending the second device path to the first.
     ///
     /// # Arguments