public static void* MapFreePage(VirtMemImpl.PageFlags flags)
{
uint physAddr = impl.FindFreePhysPageAddr();
uint virtAddr = impl.FindFreeVirtPageAddr();
//BasicConsole.WriteLine(((FOS_System.String)"Mapping free page. physAddr=") + physAddr + ", virtAddr=" + virtAddr);
Map(physAddr, virtAddr, 4096, flags);
return (void*)virtAddr;
}
/// <summary>
/// Initialises the virtual memory manager.
/// </summary>
public static void Init()
{
impl = new x86();
// Map in the kernel pages.
// - Technically this has already been done in "VirtMemInit.x86_32.asm", however,
// from the C# code perspective it has no idea so the mapping done here is to
// get the high level code's view of the memory up to speed with the actual
// state
impl.MapKernel();
}
public static void* MapFreePages(VirtMemImpl.PageFlags flags, int numPages)
{
uint virtAddrsStart = 0xDEADBEEF;
try
{
MapFreePagesLock.Enter();
//BasicConsole.WriteLine("Mapping free pages:");
uint physAddrsStart = impl.FindFreePhysPageAddrs(numPages);
virtAddrsStart = impl.FindFreeVirtPageAddrs(numPages);
//BasicConsole.Write(" -- Phys start: ");
//BasicConsole.WriteLine(physAddrsStart);
//BasicConsole.Write(" -- Virt start: ");
//BasicConsole.WriteLine(virtAddrsStart);
//BasicConsole.Write(" -- Num pages: ");
//BasicConsole.WriteLine(numPages);
for (uint i = 0; i < numPages; i++)
{
Map(physAddrsStart + (i * 4096), virtAddrsStart + (i * 4096), 4096, flags);
}
}
finally
{
MapFreePagesLock.Exit();
}
if (virtAddrsStart == 0xDEADBEEF)
{
BasicConsole.WriteLine("!!! PANIC !!!");
BasicConsole.WriteLine("VirtMemManager.MapFreePages returning 0xDEADBEEF!");
BasicConsole.WriteLine("!-!-!-!-!-!-!");
}
return (void*)virtAddrsStart;
}
/// <summary>
/// Maps the specified amount of memory.
/// </summary>
/// <param name="pAddr">The physical address to start mapping at (must be 4KiB aligned).</param>
/// <param name="vAddr">The virtual address to start mapping at (must be 4KiB aligned).</param>
/// <param name="size">The amount of memory (in bytes) to map (must be a multiple of 4KiB)</param>
public static void Map(uint pAddr, void* vAddr, uint size, VirtMemImpl.PageFlags flags, UpdateUsedPagesFlags UpdateUsedPages = UpdateUsedPagesFlags.Both)
{
Map(pAddr, (uint)vAddr, size, flags, UpdateUsedPages);
}
/// <summary>
/// Maps the specified amount of memory.
/// </summary>
/// <param name="pAddr">The physical address to start mapping at (must be 4KiB aligned).</param>
/// <param name="vAddr">The virtual address to start mapping at (must be 4KiB aligned).</param>
/// <param name="size">The amount of memory (in bytes) to map (must be a multiple of 4KiB)</param>
public static void Map(uint pAddr, uint vAddr, uint size, VirtMemImpl.PageFlags flags, UpdateUsedPagesFlags UpdateUsedPages = UpdateUsedPagesFlags.Both)
{
flags |= VirtMemImpl.PageFlags.Present | VirtMemImpl.PageFlags.Writeable;
while (size > 0)
{
impl.Map(pAddr, vAddr, flags, UpdateUsedPages);
size -= 4096;
pAddr += 4096;
vAddr += 4096;
}
}
public static void* MapFreePage(VirtMemImpl.PageFlags flags)
{
return MapFreePages(flags, 1);
}