linux-stable.git/drivers/infiniband/ulp/iser/iser_memory.c, branch linux-4.3.y

IB/iser: Add module parameter for always register memory

2015-09-25T14:46:51+00:00

This module parameter forces memory registration even for
a continuous memory region. It is true by default as sending
an all-physical rkey with remote permissions might be insecure.

Signed-off-by: Sagi Grimberg 
Signed-off-by: Doug Ledford

IB/iser: Use pd->local_dma_lkey

2015-08-30T22:12:34+00:00

Replace all leys with  pd->local_dma_lkey. This driver does not support
iWarp, so this is safe.

The insecure use of ib_get_dma_mr is thus isolated to an rkey, and this
looks trivially fixed by forcing the use of registration in a future
patch.

Signed-off-by: Jason Gunthorpe 
Reviewed-by: Sagi Grimberg 
Signed-off-by: Doug Ledford

IB/iser: Chain all iser transaction send work requests

2015-08-30T22:12:33+00:00

Chaning of send work requests benefits performance by
reducing the send queue lock contention (acquired in
ib_post_send) and saves us HW doorbells which is posted
only once.

Currently, in normal IO flows iser does not chain the CDB send
work request with the registration work request. Also in PI
flows, signature work requests are not chained as well.

Lets chain those and post only once.

Signed-off-by: Sagi Grimberg 
Signed-off-by: Doug Ledford

IB/iser: Add debug prints to the various memory registration methods

2015-08-30T22:12:32+00:00

Easier to debug when we have the registration details.

This patch does not change any functionality.

Signed-off-by: Sagi Grimberg 
Signed-off-by: Adir Lev 
Signed-off-by: Doug Ledford

IB/iser: Support up to 8MB data transfer in a single command

2015-08-30T22:12:32+00:00

iser support up to 512KB data transfer in a single scsi command.
This means that larger IOs will split to different request. While
iser can easily saturate FDR/EDR wires, some arrays are fine tuned
for 1MB (or larger) IO sizes, hence add an option to support larger
transfers (up to 8MB) if the device allows it.

Given that a few target implementations don't support data transfers
of more than 512KB by default and the fact that larger IO sizes require
more resources, we introduce a module parameter to determine the
maximum number of 512B sectors in a single scsi command.
Users that are interested in larger transfers can change this value given
that the target supports larger transfers.

At the moment, iser works in 4K pages granularity, In a later stage
we will get it to work with system page size instead.

IO operations that consists of N pages will need a page vector
of size N+1 in case the first SG element contains an offset. Given
that some devices allocates memory regions in powers of 2, this
means that allocating a region with N+1 pages, will result in
region resources allocation of the next power of 2. Since we don't
want that to happen, in case we are in the limit of IO size supported
and the first SG element has an offset, we align the SG list using a
bounce buffer (which is OK given that this is not likely to happen a lot).

Signed-off-by: Sagi Grimberg 
Signed-off-by: Doug Ledford

IB/iser: Unify fast memory registration flows

2015-08-30T22:12:31+00:00

iser_reg_rdma_mem_[fastreg|fmr] share a lot of code, and
logically do the same thing other than the buffer registration
method itself (iser_fast_reg_mr vs. iser_fast_reg_fmr).
The DIF logic is not implemented in the FMR flow as there is no
existing device that supports FMRs and Signature feature.

This patch unifies the flow in a single routine iser_reg_rdma_mem
and just split to fmr/frwr for the buffer registration itself.

Also, for symmetry reasons, unify iser_unreg_rdma_mem (which will
call the relevant device specific unreg routine).

Signed-off-by: Sagi Grimberg 
Signed-off-by: Adir Lev 
Signed-off-by: Doug Ledford

IB/iser: Make reg_desc_get a per device routine

2015-08-30T22:12:31+00:00

As for fmrs we will hold a single registration descriptor
as no need for multiple like in the frwr mode (descriptor
for each task). This change helps unifying the duplicate
registration code paths.

Signed-off-by: Sagi Grimberg 
Signed-off-by: Adir Lev 
Signed-off-by: Doug Ledford

IB/iser: Rename iser_reg_page_vec to iser_fast_reg_fmr

2015-08-30T22:12:31+00:00

Also, change a name of a local variable.

This patch does not change any functionality.

Signed-off-by: Sagi Grimberg 
Signed-off-by: Adir Lev 
Signed-off-by: Doug Ledford

IB/iser: Maintain connection fmr_pool under a single registration descriptor

2015-08-30T22:12:30+00:00

This will allow us to unify the memory registration code path between
the various methods which vary by the device capabilities. This change
will make it easier and less intrusive to remove fmr_pools from the
code when we'd want to.

The reason we use a single descriptor is to avoid taking a
redundant spinlock when working with FMRs.

We also change the signature of iser_reg_page_vec to make it match
iser_fast_reg_mr (and the future indirect registration method).

Signed-off-by: Sagi Grimberg 
Signed-off-by: Adir Lev 
Signed-off-by: Doug Ledford

IB/iser: Introduce iser registration pool struct

2015-08-30T22:12:30+00:00

Instead of having it a part of the connection structure,
have it be under a dedicated (embedded) structure in the
connection. A logical separation of the registration pool
and the connection structure.

Signed-off-by: Sagi Grimberg 
Signed-off-by: Adir Lev 
Signed-off-by: Doug Ledford