From a02ac21b74b7030647c033ed6c6793e2d69364ac Mon Sep 17 00:00:00 2001
From: John Hodge <tpg@mutabah.net>
Date: Wed, 19 Feb 2014 19:48:24 +0800
Subject: [PATCH] Kernel/x86 - Multiboot module cleanup

---
 KernelLand/Kernel/arch/x86/main.c  | 17 +++--------------
 KernelLand/Kernel/arch/x86/mboot.c | 28 ++++++++++++++++++----------
 KernelLand/Kernel/include/mboot.h  |  1 +
 3 files changed, 22 insertions(+), 24 deletions(-)

diff --git a/KernelLand/Kernel/arch/x86/main.c b/KernelLand/Kernel/arch/x86/main.c
index 93470a44..10cac716 100644
--- a/KernelLand/Kernel/arch/x86/main.c
+++ b/KernelLand/Kernel/arch/x86/main.c
@@ -134,20 +134,9 @@ void Arch_LoadBootModules(void)
 			Log_Warning("Arch", "Unable to load module");
 			continue ;
 		}
-		
-		#if 0
-		// Unmap and free
-		int numPages = (mod->Size + ((tVAddr)mod->Base&0xFFF) + 0xFFF) >> 12;
-		MM_UnmapHWPages( (tVAddr)gaArch_BootModules[i].Base, numPages );
-		
-		//for( int j = 0; j < numPages; j++ )
-		//	MM_DerefPhys( mod->PBase + (j << 12) );
-		
-		if( (tVAddr) mod->ArgString > MAX_ARGSTR_POS )
-			MM_UnmapHWPages( (tVAddr)mod->ArgString, 2 );
-		#endif
 	}
 	Log_Log("Arch", "Boot modules loaded");
-	if( gaArch_BootModules )
-		free( gaArch_BootModules );
+	Multiboot_FreeModules(giArch_NumBootModules, gaArch_BootModules);
+	giArch_NumBootModules = 0;
+	gaArch_BootModules = NULL;
 }
diff --git a/KernelLand/Kernel/arch/x86/mboot.c b/KernelLand/Kernel/arch/x86/mboot.c
index b7cebbd4..726d2d23 100644
--- a/KernelLand/Kernel/arch/x86/mboot.c
+++ b/KernelLand/Kernel/arch/x86/mboot.c
@@ -142,18 +142,26 @@ tBootModule *Multiboot_LoadModules(tMBoot_Info *MBInfo, tVAddr MapOffset, int *M
 		ret[i].Base = (void*)( (tVAddr)MM_MapHWPages(mods[i].Start, (ret[i].Size+ofs+0xFFF) / 0x1000)
 			+ ofs );
 		
-		// Only map the string if needed
-		if( !MM_GetPhysAddr( (void*)(mods[i].String + MapOffset) ) )
-		{
-			// Assumes the string is < 4096 bytes long)
-			ret[i].ArgString = (void*)(
-				(tVAddr)MM_MapHWPages(mods[i].String, 2) + (mods[i].String&0xFFF)
-				);
-		}
-		else
-			ret[i].ArgString = (char*)(tVAddr)mods[i].String + MapOffset;
+		// Assumes the string is < 4096 bytes long)
+		ret[i].ArgString = (char*)MM_MapHWPages(mods[i].String, 2) + (mods[i].String&0xFFF);
 	}
 
 	return ret;
 }
 
+void Multiboot_FreeModules(const int ModuleCount, tBootModule *Modules)
+{
+	for( int i = 0; i < ModuleCount; i ++ )
+	{
+		Uint	ofs = Modules[i].PBase % PAGE_SIZE;
+		Uint	nPages = (Modules[i].Size+ofs+PAGE_SIZE-1) / PAGE_SIZE;
+		MM_UnmapHWPages(Modules[i].Base, nPages);
+		MM_UnmapHWPages(Modules[i].ArgString, 2);
+		
+		// TODO: handle previous freeing of this page
+		for( int pg = 0; pg < nPages; pg ++ )
+			MM_DerefPhys( Modules[i].PBase + pg*PAGE_SIZE );
+	}
+	free(Modules);
+}
+
diff --git a/KernelLand/Kernel/include/mboot.h b/KernelLand/Kernel/include/mboot.h
index ad936559..6ffd5c11 100644
--- a/KernelLand/Kernel/include/mboot.h
+++ b/KernelLand/Kernel/include/mboot.h
@@ -63,5 +63,6 @@ typedef struct {
 
 extern int	Multiboot_LoadMemoryMap(tMBoot_Info *MBInfo, tVAddr MapOffset, tPMemMapEnt *Map, const int MapSize, tPAddr KStart, tPAddr KEnd);
 extern tBootModule	*Multiboot_LoadModules(tMBoot_Info *MBInfo, tVAddr MapOffset, int *ModuleCount);
+extern void	Multiboot_FreeModules(const int ModuleCount, tBootModule *Modules);
 
 #endif
-- 
2.20.1