ntoskrnl/io/iomgr/ramdisk.c

   1 /*
   2  * PROJECT:         ReactOS Kernel
   3  * LICENSE:         BSD - See COPYING.ARM in the top level directory
   4  * FILE:            ntoskrnl/io/iomgr/ramdisk.c
   5  * PURPOSE:         Allows booting from RAM disk
   6  * PROGRAMMERS:     ReactOS Portable Systems Group
   7  */
   8
   9 /* INCLUDES *******************************************************************/
  10
  11 #include <ntoskrnl.h>
  12 #include <initguid.h>
  13 #include <ntddrdsk.h>
  14 #define NDEBUG
  15 #include <debug.h>
  16
  17 /* DATA ***********************************************************************/
  18
  19 #if defined (ALLOC_PRAGMA)
  20 #pragma alloc_text(INIT, IopStartRamdisk)
  21 #endif
  22
  23 /* FUNCTIONS ******************************************************************/
  24
  25 NTSTATUS
  26 NTAPI
  27 IopStartRamdisk(IN PLOADER_PARAMETER_BLOCK LoaderBlock)
  28 {
  29     PMEMORY_ALLOCATION_DESCRIPTOR MemoryDescriptor;
  30     NTSTATUS Status;
  31     PCHAR CommandLine, Offset, OffsetValue, Length, LengthValue;
  32     HANDLE DriverHandle;
  33     RAMDISK_CREATE_INPUT RamdiskCreate;
  34     IO_STATUS_BLOCK IoStatusBlock;
  35     UNICODE_STRING GuidString, SymbolicLinkName, ObjectName, DeviceString;
  36     PLIST_ENTRY ListHead, NextEntry;
  37     OBJECT_ATTRIBUTES ObjectAttributes;
  38     WCHAR SourceString[54];
  39
  40     //
  41     // Scan memory descriptors
  42     //
  43     MemoryDescriptor = NULL;
  44     ListHead = &LoaderBlock->MemoryDescriptorListHead;
  45     NextEntry = ListHead->Flink;
  46     while (NextEntry != ListHead)
  47     {
  48         //
  49         // Get the descriptor
  50         //
  51         MemoryDescriptor = CONTAINING_RECORD(NextEntry,
  52                                              MEMORY_ALLOCATION_DESCRIPTOR,
  53                                              ListEntry);
  54
  55         //
  56         // Needs to be a ROM/RAM descriptor
  57         //
  58         if (MemoryDescriptor->MemoryType == LoaderXIPRom) break;
  59
  60         //
  61         // Keep trying
  62         //
  63         NextEntry = NextEntry->Flink;
  64     }
  65
  66     //
  67     // Nothing found?
  68     //
  69     if (NextEntry == ListHead)
  70     {
  71         //
  72         // Bugcheck -- no data
  73         //
  74         KeBugCheckEx(RAMDISK_BOOT_INITIALIZATION_FAILED,
  75                      RD_NO_XIPROM_DESCRIPTOR,
  76                      STATUS_INVALID_PARAMETER,
  77                      0,
  78                      0);
  79     }
  80
  81     //
  82     // Setup the input buffer
  83     //
  84     RtlZeroMemory(&RamdiskCreate, sizeof(RamdiskCreate));
  85     RamdiskCreate.Version = sizeof(RamdiskCreate);
  86     RamdiskCreate.DiskType = RAMDISK_BOOT_DISK;
  87     RamdiskCreate.BasePage = MemoryDescriptor->BasePage;
  88     RamdiskCreate.DiskOffset = 0;
  89     RamdiskCreate.DiskLength.QuadPart = MemoryDescriptor->PageCount << PAGE_SHIFT;
  90     RamdiskCreate.DiskGuid = RAMDISK_BOOTDISK_GUID;
  91     RamdiskCreate.DriveLetter = L'C';
  92     RamdiskCreate.Options.Fixed = TRUE;
  93
  94     //
  95     // Check for commandline parameters
  96     //
  97     CommandLine = LoaderBlock->LoadOptions;
  98     if (CommandLine)
  99     {
 100         //
 101         // Make everything upper case
 102         //
 103         _strupr(CommandLine);
 104
 105         //
 106         // Check for offset parameter
 107         //
 108         Offset = strstr(CommandLine, "RDIMAGEOFFSET");
 109         if (Offset)
 110         {
 111             //
 112             // Get to the actual value
 113             //
 114             OffsetValue = strstr(Offset, "=");
 115             if (OffsetValue)
 116             {
 117                 //
 118                 // Set the offset
 119                 //
 120                 RamdiskCreate.DiskOffset = atol(OffsetValue + 1);
 121             }
 122         }
 123
 124         //
 125         // Reduce the disk length
 126         //
 127         RamdiskCreate.DiskLength.QuadPart -= RamdiskCreate.DiskOffset;
 128
 129         //
 130         // Check for length parameter
 131         //
 132         Length = strstr(CommandLine, "RDIMAGELENGTH");
 133         if (Length)
 134         {
 135             //
 136             // Get to the actual value
 137             //
 138             LengthValue = strstr(Length, "=");
 139             if (LengthValue)
 140             {
 141                 //
 142                 // Set the offset
 143                 //
 144                 RamdiskCreate.DiskLength.QuadPart = _atoi64(LengthValue + 1);
 145             }
 146         }
 147     }
 148
 149     //
 150     // Setup object attributes
 151     //
 152     RtlInitUnicodeString(&ObjectName, L"\\Device\\Ramdisk");
 153     InitializeObjectAttributes(&ObjectAttributes,
 154                                &ObjectName,
 155                                OBJ_KERNEL_HANDLE | OBJ_CASE_INSENSITIVE,
 156                                NULL,
 157                                NULL);
 158
 159     //
 160     // Open a handle to the driver
 161     //
 162     Status = ZwOpenFile(&DriverHandle,
 163                         GENERIC_ALL,
 164                         &ObjectAttributes,
 165                         &IoStatusBlock,
 166                         FILE_SHARE_READ | FILE_SHARE_WRITE,
 167                         FILE_SYNCHRONOUS_IO_NONALERT);
 168     if (!(NT_SUCCESS(Status)) || !(NT_SUCCESS(IoStatusBlock.Status)))
 169     {
 170         //
 171         // Bugcheck -- no driver
 172         //
 173         KeBugCheckEx(RAMDISK_BOOT_INITIALIZATION_FAILED,
 174                      RD_NO_RAMDISK_DRIVER,
 175                      IoStatusBlock.Status,
 176                      0,
 177                      0);
 178     }
 179
 180     //
 181     // Send create command
 182     //
 183     Status = ZwDeviceIoControlFile(DriverHandle,
 184                                    NULL,
 185                                    NULL,
 186                                    NULL,
 187                                    &IoStatusBlock,
 188                                    FSCTL_CREATE_RAM_DISK,
 189                                    &RamdiskCreate,
 190                                    sizeof(RamdiskCreate),
 191                                    NULL,
 192                                    0);
 193     ZwClose(DriverHandle);
 194     if (!(NT_SUCCESS(Status)) || !(NT_SUCCESS(IoStatusBlock.Status)))
 195     {
 196         //
 197         // Bugcheck -- driver failed
 198         //
 199         KeBugCheckEx(RAMDISK_BOOT_INITIALIZATION_FAILED,
 200                      RD_FSCTL_FAILED,
 201                      IoStatusBlock.Status,
 202                      0,
 203                      0);
 204     }
 205
 206     //
 207     // Convert the GUID
 208     //
 209     Status = RtlStringFromGUID(&RamdiskCreate.DiskGuid, &GuidString);
 210     if (!NT_SUCCESS(Status))
 211     {
 212         //
 213         // Bugcheck -- GUID convert failed
 214         //
 215         KeBugCheckEx(RAMDISK_BOOT_INITIALIZATION_FAILED,
 216                      RD_GUID_CONVERT_FAILED,
 217                      Status,
 218                      0,
 219                      0);
 220     }
 221
 222     //
 223     // Build the symbolic link name and target
 224     //
 225     _snwprintf(SourceString,
 226                sizeof(SourceString),
 227                L"\\Device\\Ramdisk%wZ",
 228                &GuidString);
 229     SymbolicLinkName.Length = 38;
 230     SymbolicLinkName.MaximumLength = 38 + sizeof(UNICODE_NULL);
 231     SymbolicLinkName.Buffer = L"\\ArcName\\ramdisk(0)";
 232
 233     //
 234     // Create the symbolic link
 235     //
 236     RtlInitUnicodeString(&DeviceString, SourceString);
 237     Status = IoCreateSymbolicLink(&SymbolicLinkName, &DeviceString);
 238     RtlFreeUnicodeString(&GuidString);
 239     if (!NT_SUCCESS(Status))
 240     {
 241         //
 242         // Bugcheck -- symlink create failed
 243         //
 244         KeBugCheckEx(RAMDISK_BOOT_INITIALIZATION_FAILED,
 245                      RD_SYMLINK_CREATE_FAILED,
 246                      Status,
 247                      0,
 248                      0);
 249     }
 250
 251     //
 252     // We made it
 253     //
 254     return STATUS_SUCCESS;
 255 }