On 10/05/2026 23:03, Sagi Grimberg wrote:
Important new structures introduced include:
- mpath_head
These contain much of the multipath-specific functionality from
nvme_ns_head, including a pointer to the gendisk structure and
a path SRCU-based array.
I think it should be placed first in its parent struct as it holds the
hot-path
head->srcu and head->list.
Yeah, I did originally try this. However it becomes a pain for managing
the lifecycle of the mpath_head and nvme_ns_head/scsi_mpath_head
structures, especially for the scenarios like the delayed head removal.
However I can see again if I can make it work.
- mpath_device
This is the per-path structure, and contains much the same
multipath-specific functionality in nvme_ns
libmultipath provides functionality for path management, path selection,
data path, and failover handling.
Since the NVMe driver has some code in the sysfs and ioctl handling
which iterate all multipath NSes, functions like mpath_call_for_device()
are added to do the same per-path iteration.
very nice, overall seems fairly straight forward.
thanks a lot
