Thanks Brian. Netlink seems to be appropriate for our purpose as well, almost too good :-) That make me think, what's the catch? The SCSI drivers are not heavy usage of this interface for one. Are the other caveats associated with it? Best regards, Atul Mukker > -----Original Message----- > From: Brian King [mailto:brking@xxxxxxxxxxxxxxxxxx] > Sent: Friday, July 17, 2009 11:36 AM > To: Mukker, Atul > Cc: linux-scsi@xxxxxxxxxxxxxxx > Subject: Re: Recommended HBA management interfaces > > Mukker, Atul wrote: > > Hi All, > > > > We would like expert comments on the following questions regarding > > management of HBA from applications. > > > > Traditionally, our drivers create a character device node, whose > > file_operations are then used by the management applications to > > transfer HBA specific commands. In addition to being quirky, this > > interface has a few limitations which we would like to remove, most > > important being able to seamlessly handle asynchronous events with > > data transfer. > > > > 1. What is (are) the other standard/recommended interfaces which > > applications can use to transfer HBA specific commands and data. > > Depends on what the commands look like. With ipr, the commands that > the management application need to send to the HBA look sufficiently > like SCSI that I was able to report an sg device node for the adapter > and use SG_IO to send these commands. > > sysfs, debugfs, and configfs are options as well. > > > > 2. How should an LLD implement interfaces to transmit asynchronous > > information to the management applications? The requirement is to be > > able to transmit data buffer as well as notifications for events. > > I've had good success with netlink. In my use I only send a notification > to userspace and let the application send some commands to figure out > what happened, but netlink does allow to send data as well. It makes it > very > easy to have multiple concurrent readers of the data, which I've found > very > useful. > > > 3. The interface should be able to work even if no SCSI devices are > > exported to the kernel. > > netlink allows this. > > > 4. Should work seamlessly across vmware and xen kernels. > > netlink should work here too. > > -Brian > > -- > Brian King > Linux on Power Virtualization > IBM Linux Technology Center > -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
