Description of problem:

Setting queue_depth in /sys/block/sd(x)/device results in "queue_depth: 
Permission denied".  Changing permissions results in "write error: Input/output 
error".

Controller is: Marvell Technology Group Ltd. MV88SX6081 8-port SATA II PCI-X 
Controller (rev 09)

Drives are all Seagate ST3320620AS, firmware 3.AAK.  HDPARM reports NCQ 
capability, queue depth of 32.  DMESG shows disabled on boot:
ata1.00: 625142448 sectors, multi 0: LBA48 NCQ (depth 0/32)
ata2.00: 625142448 sectors, multi 0: LBA48 NCQ (depth 0/32)
ata3.00: 625142448 sectors, multi 0: LBA48 NCQ (depth 0/32)
ata4.00: 625142448 sectors, multi 0: LBA48 NCQ (depth 0/32)


Version-Release number of selected component (if applicable):

2.6.23.8-62.fc8 #1 SMP Tue Nov 20 15:25:44 EST 2007 x86_64 x86_64 x86_64 
GNU/Linux

Additional info:

I've searched and can't find that my controller and/or drives are blacklisted 
for NCQ, but this is one possibility.  sata_mv may also be missing the 
functionality to change this parameter.