Make the read/write sfp mailbox command routines uniform, and remove redundancy.
Also protect against attempting to do a single byte dma in these routines.
Signed-off-by: NJoe Carnuccio <joe.carnuccio@qlogic.com>
Signed-off-by: NMadhuranath Iyengar <Madhu.Iyengar@qlogic.com>
Signed-off-by: NJames Bottomley <jbottomley@parallels.com>
Signed-off-by: NJames Bottomley <James.Bottomley@suse.de>