kernel: Lock ATADevice::read_lba() using ATA::Channel's KMutex

kernel/src/arch/x86_64/disk/ATA.cpp

@@ -748,6 +748,8 @@ Result<u64> ATADevice::read(u8* buf, usize offset, usize size) const
 
     auto block_size = m_drive->block_size();
 
+    ScopedKMutexLock<100>(m_drive->channel()->lock());
+
     auto* temp = TRY(make_array<u8>(block_size));
     auto guard = make_scope_guard([temp] { delete[] temp; });
 

kernel/src/arch/x86_64/disk/ATA.h

@@ -157,6 +157,11 @@ namespace ATA
             return m_block_count * m_block_size;
         }
 
+        Channel* channel() const
+        {
+            return m_channel;
+        }
+
         Result<void> read_lba(u64 lba, void* out, usize nblocks);
 
         static Result<String> create_drive_name(SharedPtr<ATA::Drive> drive);
@@ -233,11 +238,16 @@ namespace ATA
         bool wait_for_irq_or_timeout(u64 timeout);
         void irq_handler(Registers*);
 
-        u8 irq_line()
+        u8 irq_line() const
         {
             return m_interrupt_line;
         }
 
+        KMutex<100>& lock()
+        {
+            return m_lock;
+        }
+
         void select(u8 drive);
 
         bool initialize();