[FREELDR]

- Simplify the implementation of the 'DiskGetBootPath' function;
- Cache the retrived freeldr boot path (corresponding to a given 'FrldrBootDrive' number);
- Introduce a 'DiskIsCdRomDrive' function to attempt to fix CORE-12692 .

svn path=/trunk/; revision=73621

reactos/boot/freeldr/freeldr/arch/i386/pcdisk.c

@@ -17,6 +17,8 @@
  *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  */
 
+// #if defined(__i386__) || defined(_M_AMD64)
+
 #include <freeldr.h>
 
 #define NDEBUG
@@ -25,6 +27,7 @@
 DBG_DEFAULT_CHANNEL(DISK);
 
 #include <pshpack2.h>
+
 typedef struct
 {
     UCHAR       PacketSize;             // 00h - Size of packet (10h or 18h)
@@ -38,6 +41,38 @@ typedef struct
                                         //       Commented since some earlier BIOSes refuse to work with
                                         //       such extended structure
 } I386_DISK_ADDRESS_PACKET, *PI386_DISK_ADDRESS_PACKET;
+
+typedef struct
+{
+    UCHAR   PacketSize;     // 00h - Size of packet in bytes (13h)
+    UCHAR   MediaType;      // 01h - Boot media type (see #00282)
+    UCHAR   DriveNumber;    /* 02h - Drive number:
+                             *   00h Floppy image
+                             *   80h Bootable hard disk
+                             *   81h-FFh Nonbootable or no emulation
+                             */
+    UCHAR   Controller;     // 03h - CD-ROM controller number
+    ULONG   LBAImage;       // 04h - Logical Block Address of disk image to emulate
+    USHORT  DeviceSpec;     /* 08h - Device specification (see also #00282)
+                             * (IDE) Bit 0:
+                             *     Drive is slave instead of master
+                             * (SCSI) Bits 7-0:
+                             *     LUN and PUN
+                             * Bits 15-8:
+                             *     Bus number
+                             */
+    USHORT  Buffer;         // 0Ah - Segment of 3K buffer for caching CD-ROM reads
+    USHORT  LoadSeg;        // 0Ch - Load segment for initial boot image.
+                            //       If 0000h, load at segment 07C0h.
+    USHORT  SectorCount;    // 0Eh - Number of 512-byte virtual sectors to load
+                            //       (only valid for AH=4Ch).
+    UCHAR   CHSGeometry[3]; /* 10h - Low byte of cylinder count (for INT 13/AH=08h)
+                             * 11h - Sector count, high bits of cylinder count (for INT 13/AH=08h)
+                             * 12h - Head count (for INT 13/AH=08h)
+                             */
+    UCHAR   Reserved;
+} I386_CDROM_SPEC_PACKET, *PI386_CDROM_SPEC_PACKET;
+
 #include <poppack.h>
 
 /* FUNCTIONS *****************************************************************/
@@ -540,6 +575,69 @@ PcDiskGetCacheableBlockCount(UCHAR DriveNumber)
     }
 }
 
+
+static BOOLEAN
+FallbackDiskIsCdRomDrive(UCHAR DriveNumber)
+{
+    MASTER_BOOT_RECORD MasterBootRecord;
+
+    TRACE("FallbackDiskIsCdRomDrive(0x%x)\n", DriveNumber);
+
+    /* CD-ROM drive numbers are always > 0x80 */
+    if (DriveNumber <= 0x80)
+        return FALSE;
+
+    /*
+     * We suppose that a CD-ROM does not have a MBR
+     * (not always true: example of the Hybrid USB-ISOs).
+     */
+    return !DiskReadBootRecord(DriveNumber, 0, &MasterBootRecord);
+}
+
+BOOLEAN DiskIsCdRomDrive(UCHAR DriveNumber)
+{
+    REGS RegsIn, RegsOut;
+    PI386_CDROM_SPEC_PACKET Packet = (PI386_CDROM_SPEC_PACKET)(BIOSCALLBUFFER);
+
+    TRACE("DiskIsCdRomDrive(0x%x)\n", DriveNumber);
+
+    /* CD-ROM drive numbers are always > 0x80 */
+    if (DriveNumber <= 0x80)
+        return FALSE;
+
+    /* Setup disk address packet */
+    RtlZeroMemory(Packet, sizeof(*Packet));
+    Packet->PacketSize = sizeof(*Packet);
+
+    /*
+     * BIOS Int 13h, function 4B01h - Bootable CD-ROM - Get Disk Emulation Status
+     * AX = 4B01h
+     * DL = drive number
+     * DS:SI -> empty specification packet
+     * Return:
+     * CF clear if successful
+     * CF set on error
+     * AX = return codes
+     * DS:SI specification packet filled
+     */
+    RegsIn.w.ax = 0x4B01;
+    RegsIn.b.dl = DriveNumber;
+    RegsIn.x.ds = BIOSCALLBUFSEGMENT;   // DS:SI -> specification packet
+    RegsIn.w.si = BIOSCALLBUFOFFSET;
+
+    Int386(0x13, &RegsIn, &RegsOut);
+
+    // return (INT386_SUCCESS(RegsOut) && (Packet->DriveNumber == DriveNumber));
+    /*
+     * If the simple test failed, try to use the fallback code,
+     * but we can be on *very* thin ice.
+     */
+    if (!INT386_SUCCESS(RegsOut) || (Packet->DriveNumber != DriveNumber))
+        return FallbackDiskIsCdRomDrive(DriveNumber);
+    else
+        return TRUE;
+}
+
 BOOLEAN
 PcDiskGetBootPath(OUT PCHAR BootPath, IN ULONG Size)
 {
@@ -550,6 +648,17 @@ PcDiskGetBootPath(OUT PCHAR BootPath, IN ULONG Size)
     // we were booting from network (and: PC --> PXE, etc...)
     // and if so, set the correct ARC path. But then this new
     // logic could be moved back to DiskGetBootPath...
+
+    if (*FrldrBootPath)
+    {
+        /* Copy back the buffer */
+        if (Size < strlen(FrldrBootPath) + 1)
+            return FALSE;
+        strncpy(BootPath, FrldrBootPath, Size);
+        return TRUE;
+    }
+
+    // FIXME! FIXME! Do this in some drive recognition procedure!!!!
     if (PxeInit())
     {
         strcpy(BootPath, "net(0)");

reactos/boot/freeldr/freeldr/disk/disk.c

@@ -25,6 +25,8 @@
 
 DBG_DEFAULT_CHANNEL(DISK);
 
+CHAR FrldrBootPath[MAX_PATH] = "";
+
 static BOOLEAN bReportError = TRUE;
 
 /* FUNCTIONS *****************************************************************/
@@ -98,93 +100,55 @@ BOOLEAN DiskIsDriveRemovable(UCHAR DriveNumber)
     return TRUE;
 }
 
-BOOLEAN
+
-DiskGetBootPath(OUT PCHAR BootPath, IN ULONG Size)
+extern BOOLEAN
+DiskIsCdRomDrive(UCHAR DriveNumber);
+
+BOOLEAN DiskGetBootPath(OUT PCHAR BootPath, IN ULONG Size)
 {
-    static char Path[] = "multi(0)disk(0)";
+    if (*FrldrBootPath)
-    char Device[4];
+        goto Done;
-    MASTER_BOOT_RECORD MasterBootRecord;
 
     /* 0x49 is our magic ramdisk drive, so try to detect it first */
     if (FrldrBootDrive == 0x49)
     {
         /* This is the ramdisk. See ArmDiskGetBootPath too... */
-
+        // sprintf(FrldrBootPath, "ramdisk(%u)", 0);
-        PCCH RamDiskPath = "ramdisk(0)";
+        strcpy(FrldrBootPath, "ramdisk(0)");
-
-        if (Size < sizeof(RamDiskPath))
-        {
-            return FALSE;
-        }
-
-        strcpy(BootPath, RamDiskPath);
     }
     else if (FrldrBootDrive < 0x80)
     {
         /* This is a floppy */
-
+        sprintf(FrldrBootPath, "multi(0)disk(0)fdisk(%u)", FrldrBootDrive);
-        if (Size <= sizeof(Path) + 7 + sizeof(Device))
+    }
+    else if (DiskIsCdRomDrive(FrldrBootDrive))
     {
-            return FALSE;
+        /* This is a CD-ROM drive */
+        sprintf(FrldrBootPath, "multi(0)disk(0)cdrom(%u)", FrldrBootDrive - 0x80);
     }
-
+    else
-        strcpy(BootPath, Path);
-
-        _itoa(FrldrBootDrive, Device, 10);
-        strcat(BootPath, "fdisk(");
-        strcat(BootPath, Device);
-        strcat(BootPath, ")");
-    }
-    /* FIXME */
-    else if (DiskReadBootRecord(FrldrBootDrive, 0, &MasterBootRecord))
     {
         ULONG BootPartition;
         PARTITION_TABLE_ENTRY PartitionEntry;
-        char Partition[4];
 
         /* This is a hard disk */
         if (!DiskGetActivePartitionEntry(FrldrBootDrive, &PartitionEntry, &BootPartition))
         {
-            DbgPrint("Invalid active partition information\n");
+            ERR("Invalid active partition information\n");
             return FALSE;
         }
 
         FrldrBootPartition = BootPartition;
 
-        if (Size <= sizeof(Path) + 18 + sizeof(Device) + sizeof(Partition))
+        sprintf(FrldrBootPath, "multi(0)disk(0)rdisk(%u)partition(%lu)",
-        {
+                FrldrBootDrive - 0x80, FrldrBootPartition);
+    }
+
+Done:
+    /* Copy back the buffer */
+    if (Size < strlen(FrldrBootPath) + 1)
         return FALSE;
-        }
+    strncpy(BootPath, FrldrBootPath, Size);
-
-        strcpy(BootPath, Path);
-
-        _itoa(FrldrBootDrive - 0x80, Device, 10);
-        strcat(BootPath, "rdisk(");
-        strcat(BootPath, Device);
-        strcat(BootPath, ")");
-
-        _itoa(FrldrBootPartition, Partition, 10);
-        strcat(BootPath, "partition(");
-        strcat(BootPath, Partition);
-        strcat(BootPath, ")");
-    }
-    else
-    {
-        /* This is a CD-ROM drive */
-
-        if (Size <= sizeof(Path) + 7 + sizeof(Device))
-        {
-            return FALSE;
-        }
-
-        strcpy(BootPath, Path);
-
-        _itoa(FrldrBootDrive - 0x80, Device, 10);
-        strcat(BootPath, "cdrom(");
-        strcat(BootPath, Device);
-        strcat(BootPath, ")");
-    }
-
     return TRUE;
 }
 

reactos/boot/freeldr/freeldr/include/disk.h

@@ -125,12 +125,17 @@ VOID DiskReportError (BOOLEAN bError);
 VOID DiskError(PCSTR ErrorString, ULONG ErrorCode);
 PCSTR DiskGetErrorCodeString(ULONG ErrorCode);
 BOOLEAN DiskIsDriveRemovable(UCHAR DriveNumber);
-extern UCHAR FrldrBootDrive;
-extern ULONG FrldrBootPartition;
-extern PVOID DiskReadBuffer;
-extern SIZE_T DiskReadBufferSize;
 
 BOOLEAN DiskGetBootPath(OUT PCHAR BootPath, IN ULONG Size);
+/* Platform-specific boot drive and partition numbers */
+extern UCHAR FrldrBootDrive;
+extern ULONG FrldrBootPartition;
+/* ARC path of the boot drive and partition */
+extern CHAR FrldrBootPath[MAX_PATH];
+
+/* Buffer for disk reads */
+extern PVOID DiskReadBuffer;
+extern SIZE_T DiskReadBufferSize;
 
 
 ///////////////////////////////////////////////////////////////////////////////////////