xref: /reactos/drivers/filesystems/fs_rec/ext.c (revision b09b5584) 
1 /*
2  * COPYRIGHT:        See COPYING in the top level directory
3  * PROJECT:          ReactOS File System Recognizer
4  * FILE:             drivers/filesystems/fs_rec/ext.c
5  * PURPOSE:          EXT Recognizer
6  * PROGRAMMER:       Eric Kohl
7  *                   Pierre Schweitzer (pierre@reactos.org)
8  */
9 
10 /* INCLUDES *****************************************************************/
11 
12 #include "fs_rec.h"
13 #include "ext.h"
14 
15 #define NDEBUG
16 #include <debug.h>
17 
18 /* FUNCTIONS ****************************************************************/
19 
20 BOOLEAN
21 NTAPI
22 FsRecIsExtVolume(IN PEXT_SUPER_BLOCK SuperBlock)
23 {
24     /* Just check for magic */
25     return (SuperBlock->Magic == EXT_SUPER_MAGIC);
26 }
27 
28 NTSTATUS
29 NTAPI
30 FsRecExtFsControl(IN PDEVICE_OBJECT DeviceObject,
31                   IN PIRP Irp)
32 {
33     PIO_STACK_LOCATION Stack;
34     NTSTATUS Status;
35     PDEVICE_OBJECT MountDevice;
36     PEXT_SUPER_BLOCK Spb = NULL;
37     ULONG SectorSize;
38     LARGE_INTEGER Offset;
39     BOOLEAN DeviceError = FALSE;
40     PAGED_CODE();
41 
42     /* Get the I/O Stack and check the function type */
43     Stack = IoGetCurrentIrpStackLocation(Irp);
44     switch (Stack->MinorFunction)
45     {
46         case IRP_MN_MOUNT_VOLUME:
47 
48             /* Assume failure */
49             Status = STATUS_UNRECOGNIZED_VOLUME;
50 
51             /* Get the device object and request the sector size */
52             MountDevice = Stack->Parameters.MountVolume.DeviceObject;
53             if (FsRecGetDeviceSectorSize(MountDevice, &SectorSize))
54             {
55                 /* Try to read the superblock */
56                 Offset.QuadPart = EXT_SB_OFFSET;
57                 if (FsRecReadBlock(MountDevice,
58                                    &Offset,
59                                    EXT_SB_SIZE,
60                                    SectorSize,
61                                    (PVOID)&Spb,
62                                    &DeviceError))
63                 {
64                     /* Check if it's an actual EXT volume */
65                     if (FsRecIsExtVolume(Spb))
66                     {
67                         /* It is! */
68                         Status = STATUS_FS_DRIVER_REQUIRED;
69                     }
70                 }
71 
72                 /* Free the boot sector if we have one */
73                 ExFreePool(Spb);
74             }
75             else
76             {
77                 /* We have some sort of failure in the storage stack */
78                 DeviceError = TRUE;
79             }
80 
81             /* Check if we have an error on the stack */
82             if (DeviceError)
83             {
84                 /* Was this because of a floppy? */
85                 if (MountDevice->Characteristics & FILE_FLOPPY_DISKETTE)
86                 {
87                     /* Let the FS try anyway */
88                     Status = STATUS_FS_DRIVER_REQUIRED;
89                 }
90             }
91 
92             break;
93 
94         case IRP_MN_LOAD_FILE_SYSTEM:
95 
96             /* Load the file system */
97             Status = FsRecLoadFileSystem(DeviceObject,
98                                          L"\\Registry\\Machine\\System\\CurrentControlSet\\Services\\Ext2fs");
99             break;
100 
101         default:
102 
103             /* Invalid request */
104             Status = STATUS_INVALID_DEVICE_REQUEST;
105     }
106 
107     /* Return Status */
108     return Status;
109 }
110 
111 /* EOF */
112