On Sat, 2010-01-09 at 14:05 +0100, Bart Van Assche wrote: > The SRP spec says that the target must specify the maximum message > size in the SRP_LOGIN_RSP information unit. The largest value one can > set the srp_sg_tablesize initiator parameter to is (max. SRP message > size defined by the target - 68) / 16. With older SCST-SRPT revisions > the maximum SRP message size was 996 bytes, hence a maximum of 58 for > srp_sg_tablesize. With newer SCST-SRPT revisions the maximum message > size defaults to 2116, which corresponds to a maximum of 128 for > srp_sg_tablesize.
I see, thanks for the reminder. It's been a while since I've had to deal with that part of the spec, and I've been fortunate that all of the vendors I work with have max message sizes that allow 255 entries. Does SRPT support the RDMA'ing the indirect buffer descriptors from the Initiator such that it isn't constrained by the partial memory descriptor list in the command request? The initiator restricts itself to 255 SG entries because I've not found a target that implemented the spec fully, though it'd be nice to be able to guarantee the ability to send larger request sizes. I think this will also become important for running bidirectional commands, since the room for descriptors cached in the command is shared for both directions. Dave -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
