FUJITA Tomonori wrote: > The target code wrongly uses netlink to pass user-space buffer > pointers. The kernel module sends SCSI commands to user space and > receives responses from user-space daemon. So we need bi-directional, > high-speed interface between user and kernel space. Currently, there > isn't such interface in mainline. For example, mmapped packet and > relayfs move data only from kernel to user space. Good-bye netlink, another ioctl (or char driver) replacement bites the dust. It looks like your netlink replacement char driver has a lot in common with the sg driver ... I hope to present soon a version 4 of the SCSI generic interface structure that will address some of these concerns. [Basically an expanded version of 'struct sg_io_hdr' that includes bidirectional data transfers and multi-protocol support.] Doug Gilbert > This patchset replaces netlink shared memory between kernel and user > spaces. The user-space daemon and the kernel module create shared > memory via mmap and use it like ring buffer (like mmapped packet > does). The poll system call is used for notification from kernel to > user space and the write system call is used for notification from > user to kernel space. We use a simple approach so that we easily > replace it if we find something better later on (or we implement a > generic interface if necessary). > > This patchset is against the scsi-target git tree and on the top of > the following patch: > > http://marc.theaimsgroup.com/?l=linux-scsi&m=114960851929878&w=2 - : 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
