implement write_block in RAMDiskDevice

3 files changed, 18 insertions, 0 deletions

diff --git a/kernel/devices/include/devices/BlockDevice.hpp b/kernel/devices/include/devices/BlockDevice.hpp
index 2f9d0aa..65d765b 100644
--- a/kernel/devices/include/devices/BlockDevice.hpp
+++ b/kernel/devices/include/devices/BlockDevice.hpp
@@ -13,6 +13,7 @@ namespace devices
     virtual ~block_device() = default;
 
     virtual auto read_block(size_t block_index, void * buffer) const -> void = 0;
+    virtual auto write_block(size_t block_index, void const * buffer) -> void = 0;
   };
 }  // namespace devices
 
diff --git a/kernel/devices/include/devices/storage/RAMDisk/RAMDiskDevice.hpp b/kernel/devices/include/devices/storage/RAMDisk/RAMDiskDevice.hpp
index de71663..b3838e4 100644
--- a/kernel/devices/include/devices/storage/RAMDisk/RAMDiskDevice.hpp
+++ b/kernel/devices/include/devices/storage/RAMDisk/RAMDiskDevice.hpp
@@ -17,6 +17,7 @@ namespace devices::storage::ram_disk
     ram_disk_device(kapi::boot_modules::boot_module const & module, size_t major, size_t minor);
 
     auto read_block(size_t block_index, void * buffer) const -> void override;
+    auto write_block(size_t block_index, void const * buffer) -> void override;
 
   private:
     kapi::boot_modules::boot_module m_boot_module{};
diff --git a/kernel/devices/src/storage/RAMDisk/RAMDiskDevice.cpp b/kernel/devices/src/storage/RAMDisk/RAMDiskDevice.cpp
index f33cf94..1bc475d 100644
--- a/kernel/devices/src/storage/RAMDisk/RAMDiskDevice.cpp
+++ b/kernel/devices/src/storage/RAMDisk/RAMDiskDevice.cpp
@@ -35,4 +35,20 @@ namespace devices::storage::ram_disk
 
     kstd::libc::memcpy(buffer, source, block_size);
   }
+
+  auto ram_disk_device::write_block(size_t block_index, void const * buffer) -> void
+  {
+    if (buffer == nullptr)
+    {
+      kapi::system::panic("[RAM DISK DEVICE] write_block called with null buffer.");
+    }
+
+    // TODO BA-FS26 add bounds checking based on module size?
+    // TODO BA-FS26 ignore writes beyond the end of the module?
+
+    auto const offset = block_index * block_size;
+    auto const destination = static_cast<std::byte *>(m_boot_module.start_address) + offset;
+
+    kstd::libc::memcpy(destination, buffer, block_size);
+  }
 }  // namespace devices::storage::ram_disk
\ No newline at end of file