mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2026-05-03 12:24:37 -04:00
895427bd01
NVME Initiator: Base modifications
This patch adds base modifications for NVME initiator support.
The base modifications consist of:
- Formal split of SLI3 rings from SLI-4 WQs (sometimes referred to as
rings as well) as implementation now widely varies between the two.
- Addition of configuration modes:
SCSI initiator only; NVME initiator only; NVME target only; and
SCSI and NVME initiator.
The configuration mode drives overall adapter configuration,
offloads enabled, and resource splits.
NVME support is only available on SLI-4 devices and newer fw.
- Implements the following based on configuration mode:
- Exchange resources are split by protocol; Obviously, if only
1 mode, then no split occurs. Default is 50/50. module attribute
allows tuning.
- Pools and config parameters are separated per-protocol
- Each protocol has it's own set of queues, but share interrupt
vectors.
SCSI:
SLI3 devices have few queues and the original style of queue
allocation remains.
SLI4 devices piggy back on an "io-channel" concept that
eventually needs to merge with scsi-mq/blk-mq support (it is
underway). For now, the paradigm continues as it existed
prior. io channel allocates N msix and N WQs (N=4 default)
and either round robins or uses cpu # modulo N for scheduling.
A bunch of module parameters allow the configuration to be
tuned.
NVME (initiator):
Allocates an msix per cpu (or whatever pci_alloc_irq_vectors
gets)
Allocates a WQ per cpu, and maps the WQs to msix on a WQ #
modulo msix vector count basis.
Module parameters exist to cap/control the config if desired.
- Each protocol has its own buffer and dma pools.
I apologize for the size of the patch.
Signed-off-by: Dick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: James Smart <james.smart@broadcom.com>
----
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Linux kernel ============ This file was moved to Documentation/admin-guide/README.rst Please notice that there are several guides for kernel developers and users. These guides can be rendered in a number of formats, like HTML and PDF. In order to build the documentation, use ``make htmldocs`` or ``make pdfdocs``. There are various text files in the Documentation/ subdirectory, several of them using the Restructured Text markup notation. See Documentation/00-INDEX for a list of what is contained in each file. Please read the Documentation/process/changes.rst file, as it contains the requirements for building and running the kernel, and information about the problems which may result by upgrading your kernel.