public static byte *Allocate4KbAlignedMemory(long size, out ThreadStats thread)
{
Debug.Assert(size >= 0);
thread = ThreadAllocations.Value;
thread.Allocations += size;
if (PlatformDetails.RunningOnPosix)
{
byte *ptr;
var rc = Syscall.posix_memalign(&ptr, (IntPtr)4096, (IntPtr)size);
if (rc != 0)
{
Syscall.ThrowLastError(rc, "Could not allocate memory");
}
return(ptr);
}
var allocate4KbAllignedMemory = Win32MemoryProtectMethods.VirtualAlloc(null, (UIntPtr)size, Win32MemoryProtectMethods.AllocationType.COMMIT,
Win32MemoryProtectMethods.MemoryProtection.READWRITE);
if (allocate4KbAllignedMemory == null)
{
ThrowFailedToAllocate();
}
return(allocate4KbAllignedMemory);
}
byte *AllocateMemoryAtEndOfPager(long totalAllocationSize)
{
if (StorageEnvironmentOptions.RunningOnPosix)
{
var p = Syscall.mmap64(new IntPtr(Env.Options.DataPager.PagerState.MapBase + totalAllocationSize), (UIntPtr)16,
MmapProts.PROT_READ | MmapProts.PROT_WRITE, MmapFlags.MAP_ANONYMOUS, -1, 0L);
if (p.ToInt64() == -1)
{
return(null);
}
return((byte *)p.ToPointer());
}
return(Win32MemoryProtectMethods.VirtualAlloc(Env.Options.DataPager.PagerState.MapBase + totalAllocationSize, new UIntPtr(16),
Win32MemoryProtectMethods.AllocationType.RESERVE, Win32MemoryProtectMethods.MemoryProtection.EXECUTE_READWRITE));
}
public static byte *Allocate(int size)
{
var remaining = size % 4096;
var sizeInPages = (size / 4096) + (remaining == 0 ? 0 : 1);
var allocatedSize = ((sizeInPages + 2) * 4096);
var virtualAlloc = Win32MemoryProtectMethods.VirtualAlloc(null, (UIntPtr)allocatedSize, Win32MemoryProtectMethods.AllocationType.COMMIT,
Win32MemoryProtectMethods.MemoryProtection.READWRITE);
if (virtualAlloc == null)
{
throw new Win32Exception(Marshal.GetLastWin32Error(), "Failed to VirtualAlloc (ElectricFence) size=" + size);
}
*(int *)virtualAlloc = allocatedSize;
Win32MemoryProtectMethods.MemoryProtection protect;
if (Win32MemoryProtectMethods.VirtualProtect(virtualAlloc, (UIntPtr)(4096), Win32MemoryProtectMethods.MemoryProtection.NOACCESS,
out protect) == false)
{
throw new Win32Exception(Marshal.GetLastWin32Error(), "Failed to VirtualProtect (ElectricFence) at address=" + new IntPtr(virtualAlloc));
}
if (Win32MemoryProtectMethods.VirtualProtect(virtualAlloc + (sizeInPages + 1) * 4096, (UIntPtr)(4096), Win32MemoryProtectMethods.MemoryProtection.NOACCESS,
out protect) == false)
{
throw new Win32Exception(Marshal.GetLastWin32Error(), "Failed to VirtualProtect (ElectricFence) at address=" + new IntPtr(virtualAlloc + (sizeInPages + 1) * 4096));
}
var firstWritablePage = virtualAlloc + 4096;
Win32UnmanagedMemory.Set(firstWritablePage, 0xED, 4096 * sizeInPages); // don't assume zero'ed mem
if (remaining == 0)
{
return(firstWritablePage);
}
// give the memory out so its end would be at the 2nd guard page
return(firstWritablePage + (4096 - remaining));
}
public static byte *Allocate4KbAlignedMemory(long size, out Sparrow.Utils.NativeMemory.ThreadStats thread)
{
Debug.Assert(size >= 0);
thread = Sparrow.Utils.NativeMemory.ThreadAllocations.Value;
thread.Allocations += size;
Interlocked.Add(ref Sparrow.Utils.NativeMemory._totalAllocatedMemory, size);
if (PlatformDetails.RunningOnPosix)
{
// we pass NULL (IntPtr.Zero) as the first parameter (address / start) so the kernel chooses the(page-aligned) address at which to create the mapping
var pageAlignedMemory = Syscall.mmap64(IntPtr.Zero, (UIntPtr)size, MmapProts.PROT_READ | MmapProts.PROT_WRITE,
MmapFlags.MAP_PRIVATE | MmapFlags.MAP_ANONYMOUS, -1, 0L);
if (pageAlignedMemory.ToInt64() == -1)
{
var err = Marshal.GetLastWin32Error();
Syscall.ThrowLastError(err,
$"Could not allocate memory (allocation size: {size / Constants.Size.Kilobyte:#,#0} kb)");
}
return((byte *)pageAlignedMemory);
}
var allocate4KbAlignedMemory = Win32MemoryProtectMethods.VirtualAlloc(null, (UIntPtr)size, Win32MemoryProtectMethods.AllocationType.COMMIT,
Win32MemoryProtectMethods.MemoryProtection.READWRITE);
if (allocate4KbAlignedMemory == null)
{
ThrowFailedToAllocate();
}
return(allocate4KbAlignedMemory);
}