kapi/device: allow removing devices from busses

1 files changed, 66 insertions, 0 deletions

diff --git a/kernel/kapi/devices/bus.cpp b/kernel/kapi/devices/bus.cpp
index dad90a15..d917eb96 100644
--- a/kernel/kapi/devices/bus.cpp
+++ b/kernel/kapi/devices/bus.cpp
@@ -9,6 +9,7 @@
 #include <kstd/string.hpp>
 #include <kstd/vector.hpp>
 
+#include <algorithm>
 #include <span>
 #include <utility>
 
@@ -23,6 +24,15 @@ namespace kapi::devices
       , m_protocol{&protocol}
   {}
 
+  bus::~bus()
+  {
+    auto children = m_devices;
+    for (auto const & child : children)
+    {
+      remove_child(*child);
+    }
+  }
+
   auto bus::add_child(kstd::shared_ptr<device> child) -> void
   {
     child->set_parent(kstd::static_pointer_cast<bus>(shared_from_this()));
@@ -32,12 +42,35 @@ namespace kapi::devices
       kapi::system::panic("[OS:DEV] Failed to register child device {}", child->name());
     }
 
+    // TODO: lock bus
+
     auto & attached = m_devices.emplace_back(std::move(child));
     attached->set_state(state::present);
 
+    // TODO: unlock bus
+
     driver_registry::get().device_attached(attached);
   }
 
+  auto bus::remove_child(device & device) -> bool  // NOLINT(misc-no-recursion)
+  {
+    // TODO: lock bus
+
+    auto found = std::ranges::find_if(m_devices, [&](auto const & d) { return d.get() == &device; });
+    if (!found)
+    {
+      return false;
+    }
+
+    auto lifeline = *found;
+    m_devices.erase(found);
+
+    // TODO: unlock bus
+
+    do_remove_child(*lifeline);
+    return true;
+  }
+
   [[nodiscard]] auto bus::children() const -> std::span<kstd::shared_ptr<device> const>
   {
     return {m_devices.data(), m_devices.size()};
@@ -57,4 +90,37 @@ namespace kapi::devices
     return device::query_facet(facet);
   }
 
+  auto bus::do_remove_child(device & device) -> void  // NOLINT(misc-no-recursion)
+  {
+    if (device.state() == state::removed)
+    {
+      return;
+    }
+
+    if (auto child_bus = device.facet<bus>())
+    {
+      auto grandchildren = kstd::vector<kstd::shared_ptr<kapi::devices::device>>{};
+      // TODO: lock child bus
+      // NOTE: this could be more efficient one vector::assign is implemented.
+      grandchildren = kstd::vector(child_bus->m_devices.begin(), child_bus->m_devices.end());
+      // TODO: unlock child bus
+
+      for (auto & grandchild : grandchildren)
+      {
+        child_bus->remove_child(*grandchild);
+      }
+    }
+
+    device.set_state(state::removed);
+
+    if (auto bound_driver = device.bound_driver())
+    {
+      bound_driver->unbind(device);
+    }
+
+    facet_registry::get().withdraw_all_for(device);
+    device_registry::get().remove(device);
+    device.set_parent(kstd::weak_ptr<bus>{});
+  }
+
 }  // namespace kapi::devices
\ No newline at end of file