I have “HL-DT-ST DVDRAM GMA-4082N” in my laptop. Few days back I burned first DVD, and it took me more than 1.5 hour :(
So, figured out that DMA is not enabled for my /dev/hdc. hdparm gives:
[root@kdlappy ~]# hdparm -v /dev/hdc/dev/hdc:Tried to enable it by:Â IO_support = 0 (default 16-bit)
 unmaskirq = 0 (off)
 using_dma = 0 (off)
 keepsettings = 0 (off)
 readonly = 0 (off)
 readahead = 256 (on)
 HDIO_GETGEO failed: Inappropriate ioctl for device
hdparm -d1 /dev/hdc/dev/hdc:Tried to compile the kernel myself, enabled almost everything under “ATA/ATAPI/MFM/RLL support” in Device Driver area, no good luck. My current kernel is 2.6.19-1.2911.6.5.fc6 Can anyone help me to enable DMA ? setting using_dma to 1 (on)
 HDIO_SET_DMA failed: Operation not permitted
 using_dma = 0 (off)
Oh, and hdparm -i gives
[root@kdlappy ~]# hdparm -i /dev/hdc/dev/hdc:Model=HL-DT-ST DVDRAM GMA-4082N, FwRev=HA01, SerialNo=M00684E5137
 Config={ Fixed Removeable DTR<=5Mbs DTR>10Mbs nonMagnetic }
 RawCHS=0/0/0, TrkSize=0, SectSize=0, ECCbytes=0
 BuffType=unknown, BuffSize=0kB, MaxMultSect=0
 (maybe): CurCHS=0/0/0, CurSects=0, LBA=yes, LBAsects=0
 IORDY=on/off, tPIO={min:120,w/IORDY:120}, tDMA={min:120,rec:120}
 PIO modes: pio0 pio1 pio2 pio3 pio4
 DMA modes: mdma0 mdma1 mdma2
 UDMA modes: udma0 udma1 *udma2
 AdvancedPM=no
 Drive conforms to: ATA/ATAPI-5 T13 1321D revision 3: ATA/ATAPI-2 ATA/ATAPI-3 ATA/ATAPI-4 ATA/ATAPI-5