IB/iser: Prevent invalidating wrong MR

The iser_reg_resources structure has two pointers to MR but only one
mr_valid field. The implementation assumes that we use only *sig_mr when
pi_enable is true. Otherwise, we use only *mr. However, it is only
sometimes correct. Read commands without protection information occur even
when pi_enble is true. For example, the following SCSI commands have a
Data-In buffer but never have protection information: READ CAPACITY (16),
INQUIRY, MODE SENSE(6), MAINTENANCE IN. So, we use
*sig_mr for some SCSI commands and *mr for the other SCSI commands.

In most cases, it works fine because the remote invalidation is applied.
However, there are two cases when the remote invalidation is not
applicable.
1. Small write commands when all data is sent as an immediate.
2. The target does not support the remote invalidation feature.

The lazy invalidation is used if the remote invalidation is impossible.
Since, at the lazy invalidation, we always invalidate the MR we want to
use, the wrong MR may be invalidated.

To fix the issue, we need a field per MR that indicates the MR needs
invalidation. Since the ib_mr structure already has such a field, let's
use ib_mr.need_inval instead of iser_reg_resources.mr_valid.

Fixes: b76a439982f8 ("IB/iser: Use IB_WR_REG_MR_INTEGRITY for PI handover")
Link: https://lore.kernel.org/r/20231219072311.40989-1-sergeygo@nvidia.com
Acked-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Signed-off-by: Sergey Gorenko <sergeygo@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

IB/iser: remove unused macros

The removed macros are old leftovers.

Reviewed-by: Sergey Gorenko <sergeygo@nvidia.com>
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Link: https://lore.kernel.org/r/20230330131333.37900-1-mgurtovoy@nvidia.com
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Leon Romanovsky <leon@kernel.org>

IB/iser: open code iser_disconnected_handler

There is a single caller to iser_disconnected_handler. Open code its
logic and remove it.

Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Link: https://lore.kernel.org/r/20221016093833.12537-4-mgurtovoy@nvidia.com
Reviewed-by: Sergey Gorenko <sergeygo@nvidia.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Leon Romanovsky <leon@kernel.org>

IB/iser: add safety checks for state_mutex lock

In some cases, we need to make sure that state_mutex is taken. Use
lockdep_assert_held to warn us in case it doesn't while it should.

Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Link: https://lore.kernel.org/r/20221016093833.12537-3-mgurtovoy@nvidia.com
Reviewed-by: Sergey Gorenko <sergeygo@nvidia.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Leon Romanovsky <leon@kernel.org>

IB/iser: open code iser_conn_state_comp_exch

There is a single caller to iser_conn_state_comp_exch. Open code its
logic and remove it.

Acked-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Signed-off-by: Sergey Gorenko <sergeygo@nvidia.com>
Link: https://lore.kernel.org/r/20221016093833.12537-2-mgurtovoy@nvidia.com
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Leon Romanovsky <leon@kernel.org>

IB/iser: Drain the entire QP during destruction flow

It's important to drain both the sq and the rq to make sure all WRs were
flushed before destroying the QP.

Link: https://lore.kernel.org/r/20220615082839.26328-1-mgurtovoy@nvidia.com
Reviewed-by: Sergey Gorenko <sergeygo@nvidia.com>
Reviewed-by: Israel Rukshin <israelr@nvidia.com>
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

RDMA: Split kernel-only global device caps from uverbs device caps

Split out flags from ib_device::device_cap_flags that are only used
internally to the kernel into kernel_cap_flags that is not part of the
uapi. This limits the device_cap_flags to being the same bitmap that will
be copied to userspace.

This cleanly splits out the uverbs flags from the kernel flags to avoid
confusion in the flags bitmap.

Add some short comments describing which each of the kernel flags is
connected to. Remove unused kernel flags.

Link: https://lore.kernel.org/r/0-v2-22c19e565eef+139a-kern_caps_jgg@nvidia.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

IB/iser: Use iser_fr_desc as registration context

After removing the FMR support in iSER, there is only one type of
registration context. Replace the void pointer with the explicit structure
for registration (struct iser_fr_desc).

Link: https://lore.kernel.org/r/20220308145546.8372-3-mgurtovoy@nvidia.com
Reviewed-by: Sergey Gorenko <sergeygo@nvidia.com>
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Acked-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

RDMA/iser: Delete useless module.h include

There is no need in include of module.h in the following files.

Link: https://lore.kernel.org/r/bdbf940ca5edbbc649153fa15737b779c073c498.1642960861.git.leonro@nvidia.com
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Acked-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

IB/iser: Align coding style across driver

The following changes were made:
1. Align function signatures to 80 characters per line.
2. Remove tabs for variable assignment and use 1 space instead.
3. Don't compare to NULL in "if" clause.
4. Remove strange indentations.

This will ease on the maintenance of the driver for the future.

Link: https://lore.kernel.org/r/20211215135721.3662-7-mgurtovoy@nvidia.com
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

IB/iser: Remove un-needed casting to/from void pointer

The void pointer can be typecasted to/from any type.

Link: https://lore.kernel.org/r/20211215135721.3662-6-mgurtovoy@nvidia.com
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

IB/iser: Don't suppress send completions

In order to complete a scsi command and guarantee that the HCA will never
perform an access violation when retrying a send operation we must
complete a scsi request only when both send and receive completions has
arrived. This is a preparation commit that remove the send completions
suppression. Next step will be taking care of the local invalidation
mechanism and adding a reference counter for commands. Currently, we
don't do anything upon getting the send completion and just "consume" it.

Link: https://lore.kernel.org/r/20211215135721.3662-5-mgurtovoy@nvidia.com
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Reviewed-by: Israel Rukshin <israelr@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

IB/iser: Rename ib_ret local variable

Use more common name for return values ("ret"). This commit doesn't change
any logic.

Link: https://lore.kernel.org/r/20211215135721.3662-4-mgurtovoy@nvidia.com
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Reviewed-by: Israel Rukshin <israelr@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

IB/iser: Fix RNR errors

Some users complain about RNR errors on the target, when heavy
high-priority tasks run on the initiator. After the investigation, we
found out that the receive WRs were exhausted, because the initiator could
not post them on time.

Receive work reqeusts are posted in chunks to reduce the number of hits to
the HCA. The WRs are posted in the receive completion handler when the
number of free receive buffers reaches the threshold. But on a high-loaded
host, receive CQEs processing can be delayed and all receive WRs will be
exhausted. In this case, the target will get an RNR error.

To avoid this, we post receive WR, as soon as possible and not in a
batch. This increases the number of hits to the HCA, but also the common
implementation in most of Linux ULPs (e.g. NVMe-oF/RDMA). As a rule of
thumb, performance improvements and heuristics are being added to the RDMA
core layer or vendors low level drivers and it's about time to align iSER
as well.

Link: https://lore.kernel.org/r/20211215135721.3662-3-mgurtovoy@nvidia.com
Signed-off-by: Sergey Gorenko <sergeygo@nvidia.com>
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Reviewed-by: Israel Rukshin <israelr@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

scsi: iser: Use scsi_get_sector() instead of scsi_get_lba()

Use scsi_get_sector() instead of scsi_get_lba() since the name of the
latter is confusing. This patch does not change any functionality.

Link: https://lore.kernel.org/r/20210513223757.3938-3-bvanassche@acm.org
Link: https://lore.kernel.org/r/20210609033929.3815-12-martin.petersen@oracle.com
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Message-Id: <20210609033929.3815-12-martin.petersen@oracle.com>

RDMA: Fix kernel-doc warnings about wrong comment

Compilation with W=1 produces warnings similar to the below.

drivers/infiniband/ulp/ipoib/ipoib_main.c:320: warning: This comment
starts with '/**', but isn't a kernel-doc comment. Refer
Documentation/doc-guide/kernel-doc.rst

All such occurrences were found with the following one line
git grep -A 1 "\/\*\*" drivers/infiniband/

Link: https://lore.kernel.org/r/e57d5f4ddd08b7a19934635b44d6d632841b9ba7.1623823612.git.leonro@nvidia.com
Reviewed-by: Jack Wang <jinpu.wang@ionos.com> #rtrs
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@cornelisnetworks.com>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

IB/iser: Remove unneeded semicolons

No need to add semicolon after closing bracket.

Link: https://lore.kernel.org/r/20210111145754.56727-2-mgurtovoy@nvidia.com
Reviewed-by: Israel Rukshin <israelr@nvidia.com>
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

RDMA: Add rdma_connect_locked()

There are two flows for handling RDMA_CM_EVENT_ROUTE_RESOLVED, either the
handler triggers a completion and another thread does rdma_connect() or
the handler directly calls rdma_connect().

In all cases rdma_connect() needs to hold the handler_mutex, but when
handler's are invoked this is already held by the core code. This causes
ULPs using the 2nd method to deadlock.

Provide a rdma_connect_locked() and have all ULPs call it from their
handlers.

Link: https://lore.kernel.org/r/0-v2-53c22d5c1405+33-rdma_connect_locking_jgg@nvidia.com
Reported-and-tested-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Fixes: 2a7cec538169 ("RDMA/cma: Fix locking for the RDMA_CM_CONNECT state")
Acked-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Acked-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

treewide: Use fallthrough pseudo-keyword

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

IB/iser: use new shared CQ mechanism

Have the driver use shared CQs provided by the rdma core driver. Since
this provides similar functionality to iser_comp it has been removed. Now
there is no reason to allocate very large CQs when the driver is loaded
while gaining the advantage of shared CQs.

Link: https://lore.kernel.org/r/20200722135629.49467-1-maxg@mellanox.com
Signed-off-by: Yamin Friedman <yaminf@mellanox.com>
Acked-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

RDMA/iser: Remove support for FMR memory registration

FMR is not supported on most recent RDMA devices (that use fast memory
registration mechanism). Also, FMR was recently removed from NFS/RDMA
ULP.

Link: https://lore.kernel.org/r/1-v3-f58e6669d5d3+2cf-fmr_removal_jgg@mellanox.com
Signed-off-by: Israel Rukshin <israelr@mellanox.com>
Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

IB/iser: use true,false for bool variable

Fixes coccicheck warning:

drivers/infiniband/ulp/iser/iser_memory.c:530:2-21: WARNING: Assignment of 0/1 to bool variable
drivers/infiniband/ulp/iser/iser_verbs.c:1096:2-21: WARNING: Assignment of 0/1 to bool variable

Link: https://lore.kernel.org/r/1577176812-2238-4-git-send-email-zhengbin13@huawei.com
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

infiniband: fix ulp/iser/iser_verbs.c kernel-doc notation

Various kernel-doc fixes:

- fix typos
- don't use /** for internal structs or functions
- fix Return: kernel-doc formatting
- add kernel-doc notation for missing function parameters

../drivers/infiniband/ulp/iser/iser_verbs.c:159: warning: Function parameter or member 'ib_conn' not described in 'iser_alloc_fmr_pool'
../drivers/infiniband/ulp/iser/iser_verbs.c:159: warning: Function parameter or member 'cmds_max' not described in 'iser_alloc_fmr_pool'
../drivers/infiniband/ulp/iser/iser_verbs.c:159: warning: Function parameter or member 'size' not described in 'iser_alloc_fmr_pool'
../drivers/infiniband/ulp/iser/iser_verbs.c:221: warning: Function parameter or member 'ib_conn' not described in 'iser_free_fmr_pool'
../drivers/infiniband/ulp/iser/iser_verbs.c:304: warning: Function parameter or member 'ib_conn' not described in 'iser_alloc_fastreg_pool'
../drivers/infiniband/ulp/iser/iser_verbs.c:304: warning: Function parameter or member 'cmds_max' not described in 'iser_alloc_fastreg_pool'
../drivers/infiniband/ulp/iser/iser_verbs.c:304: warning: Function parameter or member 'size' not described in 'iser_alloc_fastreg_pool'
../drivers/infiniband/ulp/iser/iser_verbs.c:338: warning: Function parameter or member 'ib_conn' not described in 'iser_free_fastreg_pool'
../drivers/infiniband/ulp/iser/iser_verbs.c:568: warning: Function parameter or member 'iser_conn' not described in 'iser_conn_release'
../drivers/infiniband/ulp/iser/iser_verbs.c:603: warning: Function parameter or member 'iser_conn' not described in 'iser_conn_terminate'
../drivers/infiniband/ulp/iser/iser_verbs.c:1040: warning: Function parameter or member 'signal' not described in 'iser_post_send'
../drivers/infiniband/ulp/iser/iser_verbs.c:1040: warning: Function parameter or member 'ib_conn' not described in 'iser_post_send'
../drivers/infiniband/ulp/iser/iser_verbs.c:1040: warning: Function parameter or member 'tx_desc' not described in 'iser_post_send'

Link: https://lore.kernel.org/r/20191010035240.070520193@gmail.com
Signed-off-by: Randy Dunlap <rd.dunlab@gmail.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

RDMA/iser: Use iser_err instead of pr_err for logging

Make sure all the debug prints in ib_iser module use the common driver
logger.

Link: https://lore.kernel.org/r/1570366580-24097-1-git-send-email-maxg@mellanox.com
Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

IB/iser: remove redundant macro definitions

Use the general linux definition for 4K and retrieve the rest from it.

Link: https://lore.kernel.org/r/1569359148-12312-1-git-send-email-maxg@mellanox.com
Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

IB/iser: add unlikely checks in the fast path

ib_post_send, ib_post_recv and ib_dma_map_sg operations should succeed
unless something unusual happened to the ib device.

Link: https://lore.kernel.org/r/1569274369-29217-1-git-send-email-maxg@mellanox.com
Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
Acked-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

RDMA/core: Rename signature qp create flag and signature device capability

Rename IB_QP_CREATE_SIGNATURE_EN to IB_QP_CREATE_INTEGRITY_EN
and IB_DEVICE_SIGNATURE_HANDOVER to IB_DEVICE_INTEGRITY_HANDOVER.

Signed-off-by: Israel Rukshin <israelr@mellanox.com>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

IB/iser: Unwind WR union at iser_tx_desc

After decreasing WRs array size from 7 to 3 it is more
readable to give each WR a descriptive name.

Signed-off-by: Israel Rukshin <israelr@mellanox.com>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

IB/iser: Use IB_WR_REG_MR_INTEGRITY for PI handover

Using this new API reduces iSER code complexity.
It also reduces the maximum number of work requests per task and the need
of dealing with multiple MRs (and their registrations and invalidations)
per task. It is done by using a single WR and a special MR type
(IB_MR_TYPE_INTEGRITY) for PI operation.

The setup of the tested benchmark:
- 2 servers with 24 cores (1 initiator and 1 target)
- 24 target sessions with 1 LUN each
- ramdisk backstore
- PI active

Performance results running fio (24 jobs, 128 iodepth) using
write_generate=0 and read_verify=0 (w/w.o patch):

bs IOPS(read) IOPS(write)
---- ---------- ----------
512 1236.6K/1164.3K 1357.2K/1332.8K
1k 1196.5K/1163.8K 1348.4K/1262.7K
2k 1016.7K/921950 1003.7K/931230
4k 662728/600545 595423/501513
8k 385954/384345 333775/277090
16k 222864/222820 170317/170671
32k 116869/114896 82331/82244
64k 55205/54931 40264/40021

Using write_generate=1 and read_verify=1 (w/w.o patch):

bs IOPS(read) IOPS(write)
---- ---------- ----------
512 1090.1K/1030.9K 1303.9K/1101.4K
1k 1057.7K/904583 1318.4K/988085
2k 965226/638799 1008.6K/692514
4k 555479/410151 542414/414517
8k 298675/224964 264729/237508
16k 133485/122481 164625/138647
32k 74329/67615 80143/78743
64k 35716/35519 39294/37334

We get performance improvement at all block sizes.
The most significant improvement is when writing 4k bs (almost 30% more
iops).

Signed-off-by: Israel Rukshin <israelr@mellanox.com>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

iser: set sector for ambiguous mr status errors

If for some reason we failed to query the mr status, we need to make sure
to provide sufficient information for an ambiguous error (guard error on
sector 0).

Fixes: 0a7a08ad6f5f ("IB/iser: Implement check_protection")
Cc: <stable@vger.kernel.org>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

RDMA/ulp: Use dev_name instead of ibdev->name

These return the same thing but dev_name is a more conventional use of the
kernel API.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>

IB/iser: Simplify ib_post_(send|recv|srq_recv)() calls

Instead of declaring and passing a dummy 'bad_wr' pointer, pass NULL
as third argument to ib_post_(send|recv|srq_recv)().

Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>

IB/iser: Do not reduce max_sectors

The iSER driver reduces max_sectors. For example, if you load the
ib_iser module with max_sectors=1024, you will see that
/sys/class/block/<bdev>/queue/max_hw_sectors_kb is 508. It is an
incorrect value. The expected value is (max_sectors * sector_size) /
1024 = 512.

Reducing of max_sectors can cause performance degradation due to
unnecessary splitting of IO requests.

The number of pages per MR has been fixed here, so there is no longer
any need to reduce max_sectors.

Fixes: 9c674815d346 ("IB/iser: Fix max_sectors calculation")
Signed-off-by: Sergey Gorenko <sergeygo@mellanox.com>
Reviewed-by: Israel Rukshin <israelr@mellanox.com>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Sagi Grimberg <sagi@grimberg.me>
Acked-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/{ipoib, iser}: Consistent print format of vendor error

Vendor error print should be consistent across protocols to avoid any
confusion.
This patch corrects that.

Suggested-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Signed-off-by: Ajaykumar Hotchandani <ajaykumar.hotchandani@oracle.com>
Reviewed-by: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Acked-by: Wengang Wang <wen.gang.wang@oracle.com>
Reviewed-by: Yuval Shaia <yuval.shaia@oracle.com>
Signed-off-by: Yuval Shaia <yuval.shaia@oracle.com>
Acked-by: Sagi Grimberg <sagi@grimberg.me>
Acked-by: Roi Dayan <roid@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

RDMA/(core, ulp): Convert register/unregister event handler to be void

The functions ib_register_event_handler() and
ib_unregister_event_handler() always returned success and they can't fail.

Let's convert those functions to be void, remove redundant checks and
cleanup tons of goto statements.

Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/iser: Handle lack of memory management extentions correctly

max_fast_reg_page_list_len is only valid when the
memory management extentions are signaled by the underlying
driver.

Fix by adjusting iser_calc_scsi_params() to use
ISCSI_ISER_MAX_SG_TABLESIZE when the extentions are not indicated.

Reported-by: Thomas Rosenstein <thomas.rosenstein@creamfinance.com>
Fixes: Commit df749cdc45d9 ("IB/iser: Support up to 8MB data transfer in a single command")
Reviewed-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Acked-by: Sagi Grimberg <sagi@grimberg.me>
Tested-by: Thomas Rosenstein <thomas.rosenstein@creamfinance.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

RDMA/iser: Fix possible mr leak on device removal event

When the rdma device is removed, we must cleanup all
the rdma resources within the DEVICE_REMOVAL event
handler to let the device teardown gracefully. When
this happens with live I/O, some memory regions are
occupied. Thus, track them too and dereg all the mr's.

We are safe with mr access by iscsi_iser_cleanup_task.

Reported-by: Raju Rangoju <rajur@chelsio.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/iser: Protect completion context active_qps update

As iser connections can share completion contexts, we need
to protect the active_qps update each time we set it.

Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
Acked-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/iser: remove unused variable from iser_conn struct

max_sectors calculation was fixed in commit:
9c674815d346 ("IB/iser: Fix max_sectors calculation").
Thus, iser_conn variable scsi_max_sectors is not needed anymore.

Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Tested-by: Raju Rangoju <rajur@chelsio.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

ib_iser: log the connection reject message

Acked-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/iser: use IB_PD_UNSAFE_GLOBAL_RKEY

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/core: add support to create a unsafe global rkey to ib_create_pd

Instead of exposing ib_get_dma_mr to ULPs and letting them use it more or
less unchecked, this moves the capability of creating a global rkey into
the RDMA core, where it can be easily audited. It also prints a warning
everytime this feature is used as well.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Reviewed-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

iser: Accept arbitrary sg lists mapping if the device supports it

If the device support arbitrary sg list mapping (device cap
IB_DEVICE_SG_GAPS_REG set) we allocate the memory regions with
IB_MR_TYPE_SG_GAPS and allow the block layer to pass us
gaps by skip setting the queue virt_boundary.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/iser: Use ib_drain_sq()

Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/iser: Support the remote invalidation exception

Declare that we support remote invalidation in case we are:
1. using fastreg method
2. always registering memory

Detect the invalidated rkey from the work completion info so we
won't invalidate it locally. The spec mandates that we must not rely
on the target remote invalidate our rkey so we must check it upon
a receive (scsi response) completion.

Signed-off-by: Jenny Derzhavetz <jennyf@mellanox.com>
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/iser,isert: Create and use new shared header

The iser RDMA_CM negotiation protocol is shared by
the initiator and the target, so have a shared header
for the defines and structure. Move relevant items from
the initiator and target headers.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Jenny Derzhavetz <jennyf@mellanox.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/iser: set intuitive values for mr_valid

This parameter is described as "is mr valid indicator".
In other words, it indicates whether memory registration
is valid or not. So intuitive values would be:
mr_valid=True, when memory registration is valid and
mr_valid=False otherwise.

Signed-off-by: Jenny Derzhavetz <jennyf@mellanox.com>
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/ulps: Avoid calling ib_query_device

Instead, use the cached copy of the attributes present on the device.

Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/iser: Convert to CQ abstraction

Use the new CQ abstraction to simplify completions in the iSER
initiator.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

IB/iser: Use helper for container_of

Nicer this way.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

IB/iser: Use a dedicated descriptor for login

We'll need it later with the new CQ abstraction. also switch
login bufs to void pointers.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

IB/iser: use sector_div instead of do_div

do_div is the wrong way to divide a sector_t, as it is less
efficient when sector_t is 32-bit wide. With the upcoming
do_div optimizations, the kernel starts warning about this:

drivers/infiniband/ulp/iser/iser_verbs.c:1296:4: note: in expansion of macro 'do_div'
include/asm-generic/div64.h:224:22: warning: passing argument 1 of '__div64_32' from incompatible pointer type

This changes the code to use sector_div instead, which always
produces optimal code.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/iser: Port to new fast registration API

Remove fastreg page list allocation as the page vector
is now private to the provider. Instead of constructing
the page list and fast_req work request, call ib_map_mr_sg
and construct ib_reg_wr.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/cma: Add support for network namespaces

Add support for network namespaces in the ib_cma module. This is
accomplished by:

1. Adding network namespace parameter for rdma_create_id. This parameter is
used to populate the network namespace field in rdma_id_private.
rdma_create_id keeps a reference on the network namespace.
2. Using the network namespace from the rdma_id instead of init_net inside
of ib_cma, when listening on an ID and when looking for an ID for an
incoming request.
3. Decrementing the reference count for the appropriate network namespace
when calling rdma_destroy_id.

In order to preserve the current behavior init_net is passed when calling
from other modules.

Signed-off-by: Guy Shapiro <guysh@mellanox.com>
Signed-off-by: Haggai Eran <haggaie@mellanox.com>
Signed-off-by: Yotam Kenneth <yotamke@mellanox.com>
Signed-off-by: Shachar Raindel <raindel@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB: split struct ib_send_wr

This patch split up struct ib_send_wr so that all non-trivial verbs
use their own structure which embedds struct ib_send_wr. This dramaticly
shrinks the size of a WR for most common operations:

sizeof(struct ib_send_wr) (old): 96

sizeof(struct ib_send_wr): 48
sizeof(struct ib_rdma_wr): 64
sizeof(struct ib_atomic_wr): 96
sizeof(struct ib_ud_wr): 88
sizeof(struct ib_fast_reg_wr): 88
sizeof(struct ib_bind_mw_wr): 96
sizeof(struct ib_sig_handover_wr): 80

And with Sagi's pending MR rework the fast registration WR will also be
down to a reasonable size:

sizeof(struct ib_fastreg_wr): 64

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com> [srp, srpt]
Reviewed-by: Chuck Lever <chuck.lever@oracle.com> [sunrpc]
Tested-by: Haggai Eran <haggaie@mellanox.com>
Tested-by: Sagi Grimberg <sagig@mellanox.com>
Tested-by: Steve Wise <swise@opengridcomputing.com>

IB/iser: Add module parameter for always register memory

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 <sagig@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/core: Make ib_dealloc_pd return void

The majority of callers never check the return value, and even if they
did, they can't do anything about a failure.

All possible failure cases represent a bug in the caller, so just
WARN_ON inside the function instead.

This fixes a few random errors:
net/rd/iw.c infinite loops while it fails. (racing with EBUSY?)

This also lays the ground work to get rid of error return from the
drivers. Most drivers do not error, the few that do are broken since
it cannot be handled.

Since uverbs can legitimately make use of EBUSY, open code the
check.

Signed-off-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Reviewed-by: Chuck Lever <chuck.lever@oracle.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/iser: Use pd->local_dma_lkey

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 <jgunthorpe@obsidianresearch.com>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/iser: Chain all iser transaction send work requests

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 <sagig@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

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

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 <sagig@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/iser: Pass registration pool a size parameter

Hard coded for now. This will allow to allocate different
sized MRs depending on the IO size needed (and device
capabilities).

This patch does not change any functionality.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

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

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 <sagig@mellanox.com>
Signed-off-by: Adir Lev <adirl@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/iser: Introduce iser registration pool struct

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 <sagig@mellanox.com>
Signed-off-by: Adir Lev <adirl@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/iser: Move fastreg descriptor allocation to iser_create_fastreg_desc

Don't have the caller allocate the structure and worry about
freeing it in case the routine failed.

This patch does not change any functionality.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Adir Lev <adirl@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/iser: Introduce iser_reg_ops

Move all the per-device function pointers to an easy
extensible iser_reg_ops structure that contains all
the iser registration operations.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/iser: Remove dead code in fmr_pool alloc/free

In the past the we always tried to allocate an fmr_pool
and if it failed on ENOSYS (not supported) then we continued
with dma mr. This is not the case anymore and if we tried to
allocate an fmr_pool then it is supported and we expect to succeed.

Also, the check if fmr_pool is allocated when free is called is
redundant as well as we are guaranteed it exists.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/iser: Rename struct fast_reg_descriptor -> iser_fr_desc

Avoid struct names without iser_ prefix.

This patch does not change any functionality.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/iser: Introduce struct iser_reg_resources

Have fast_reg_descriptor hold struct iser_reg_resources
(mr, frpl, valid flag). This will be useful when the
actual buffer registration routines will be passed with
the needed registration resources (i.e. iser_reg_resources)
without being aware of their nature (i.e. data or protection).

In order to achieve this, we remove reg_indicators flags container
and place specific flags (mr_valid) within iser_reg_resources struct.
We also place the sig_mr_valid and sig_protcted flags in iser_pi_context.

This patch also modifies iser_fast_reg_mr to receive the
reg_resources instead of the fast_reg_descriptor and a data/protection
indicator.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Adir Lev <adirl@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/iser: Convert to ib_alloc_mr

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB: Modify ib_create_mr API

Use ib_alloc_mr with specific parameters.
Change the existing callers.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/core: Get rid of redundant verb ib_destroy_mr

This was added in a thought of uniting all mr allocation
and deallocation routines but the fact is we have a single
deallocation routine already, ib_dereg_mr.

And, move mlx5_ib_destroy_mr specific logic into mlx5_ib_dereg_mr
(includes only signature stuff for now).

And, fixup the only callers (iser/isert) accordingly.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/core: Change ib_create_cq to use struct ib_cq_init_attr

Currently, ib_create_cq uses cqe and comp_vecotr instead
of the extendible ib_cq_init_attr struct.

Earlier patches already changed the vendors to work with
ib_cq_init_attr. This patch changes the consumers too.

Signed-off-by: Matan Barak <matanb@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/iser: Align to generic logging helpers

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/iser: Move PI context alloc/free to routines

Make iser_[create|destroy]_fastreg_desc shorter, more
readable and easily extendable.

This patch does not change any functionality.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Adir Lev <adirl@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/iser: Get rid of struct iser_rdma_regd

This struct members other than struct iser_mem_reg are unused,
so remove it altogether.

This patch does not change any functionality.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Adir Lev <adirl@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/iser: Move memory reg/dereg routines to iser_memory.c

As memory registration/de-registration methods, lets
move them to their natural location. While we're at it,
make iser_reg_page_vec routine static.

This patch does not change any functionality.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/iser: Handle fastreg/local_inv completion errors

Fast registration and local invalidate work requests can
also fail. We should call error completion handler for them.

Reported-by: Roi Dayan <roid@mellanox.com>
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/iser: Fix unload during ep_poll wrong dereference

In case the user unloaded ib_iser while ep_connect is in
progress, we need to destroy the endpoint although ep_disconnect
wasn't invoked (we detect this by the iser conn state != DOWN).
However, if we got an REJECTED/UNREACHABLE CM event we move the
connection state to DOWN which will prevent us from destroying
the endpoint in the module unload stage. Fix this by setting the
connection state to TERMINATING in iser_conn_error so we can still
destroy the endpoint at unload stage.

Reported-by: Ariel Nahum <arieln@mellanox.com>
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>

IB/iser: Release the iscsi endpoint if ep_disconnect wasn't called

In some cases, we might reach the iser connection termination without
ep_disconnect being invoked (for example if user-space daemon doesn't
exists. In this case, we need to free the iscsi endpoint when we
remove the iser connection.

Signed-off-by: Ariel Nahum <arieln@mellanox.com>
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Fix memory regions possible leak

When teardown process starts during live IO, we need to keep the
memory regions pool (frmr/fmr) until all in-flight tasks are properly
released, since each task may return a memory region to the pool. In
order to do this, we pass a destroy flag to iser_free_ib_conn_res to
indicate we can destroy the device and the memory regions
pool. iser_conn_release will pass it as true and also DEVICE_REMOVAL
event (we need to let the device to properly remove).

Also, Since we conditionally call iser_free_rx_descriptors,
remove the extra check on iser_conn->rx_descs.

Fixes: 5426b1711fd0 ("IB/iser: Collapse cleanup and disconnect handlers")
Reported-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Micro-optimize iser_handle_wc

Use likely() for wc.status == IB_WC_SUCCESS

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Use more completion queues

No reason to settle with four, can use the min between device max comp
vectors and number of cores.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Remove redundant is_mr indicator

It is enough to check mem_h pointer assignment, mem_h == NULL will
indicate that buffer is not registered using mr.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Fix sparse warnings

Use uintptr_t to handle wr_id casting, which was found by Kbuild test
robot and smatch. Also remove an internal definition of variable which
potentially shadows an external one (and make sparse happy).

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Decrement CQ's active QPs accounting when QP creation fails

When creating a connection QP we choose the least used CQ and inc the
number of active QPs on that. If we fail to create the QP, we need to
decrement the active QPs counter.

Reported-by: Roi Dayan <roid@mellanox.com>
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Collapse cleanup and disconnect handlers

No real need to wait for TIMEWAIT_EXIT before we destroy the RDMA
resources (also TIMEAWAIT_EXIT is not guarenteed to always arrive). As
for the cma_id, only destroy it if the state is not DOWN where in this
case, conn_release is already running and we don't want to compete.

Signed-off-by: Ariel Nahum <arieln@mellanox.com>
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Fix catastrophic error flow hang

In case of the HCA going into catasrophic error flow, the
beacon post_send is likely to fail, so surely there will
be no completion for it.

In this case, use a best effort approach and don't wait for beacon
completion if we failed to post the send.

Reported-by: Alex Tabachnik <alext@mellanox.com>
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Re-adjust CQ and QP send ring sizes to HW limits

Re-adjust max CQEs per CQ and max send_wr per QP according
to the resource limits supported by underlying hardware.

Signed-off-by: Minh Tran <minhduc.tran@emulex.com>
Signed-off-by: Jayamohan Kallickal <jayamohan.kallickal@emulex.com>
Acked-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Suppress scsi command send completions

Singal completion of every 32 scsi commands and suppress all the rest.
We don't do anything upon getting the completion so no need to "just
consume" it. Cleanup of scsi command is done in cleanup_task callback.

Still keep dataout and control send completions as we may need to
cleanup there. This helps reducing the amount of interrupts/completions
in the IO path.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Optimize completion polling

Poll in batch of 16. Since we don't want it on the stack, keep under
iser completion context (iser_comp).

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Use beacon to indicate all completions were consumed

Avoid post_send counting (atomic) in the IO path just to keep track of
how many completions we need to consume. Use a beacon post to indicate
that all prior posts completed.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Use single CQ for RX and TX

This will solve a possible condition where we might miss TX completion
(flush error) during session teardown. Since we are using a single
CQ, we don't need to actively drain the TX CQ, instead just wait for
flush_completion (when counters reach zero) and remove iser_poll_for_flush_errors().

This patch might introduce a minor performance regression on its own,
but the next patches will enhance performance using a single CQ for RX
and TX.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Use internal polling budget to avoid possible live-lock

We need a way to guarentee that we don't stay in soft-IRQ context for
too long. We might starve other pending CQ tasklets or worse lock
against application trying to issue IO on the running CPU.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Roi Dayan <roid@mellanox.com>
Signed-off-by: Ariel Nahum <arieln@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Centralize iser completion contexts

Introduce iser_comp which centralizes all iser completion related
items and is referenced by iser_device and each ib_conn.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Use iser_warn instead of BUG_ON in iser_conn_release

In case iscsid was violently killed (SIGKILL) during its error
recovery stage, we may never get a connection teardown sequence for
some of the old connections. No harm done, but when we try to unload
the module we will need to cleanup all these connections. So we
actually may end-up here - so it's not a BUG_ON(), just give a relaxed
warning that this happened and continue with normal unload. BUG_ON()
will cause segfault on module_exit and we don't want that.

Signed-off-by: Ariel Nahum <arieln@mellanox.com>
Signed-off-by: Roi Dayan <roid@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Signal iSCSI layer that transport is broken in error completions

Previously we notified iscsi layer about the connection layer when
we consumed all of our flush errors. This was racy as there
was no guarentee that iscsi_conn wasn't terminated by then (which ends
up in an invalid memory access). In case we got a non FLUSH error
completion, we are guarenteed that iscsi_conn is still alive. We should
notify iSCSI layer with iscsi_conn_failure to initiate error handling.

While we are at it, add a nice kernel-doc style documentation.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Ariel Nahum <arieln@mellanox.com>
Signed-off-by: Roi Dayan <roid@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Don't bound release_work completions timeouts

We no longer rely on iscsi connection teardown sequence, so no need to
give a grace period and continue cleanup if it expired. Have
iser_conn_release wait for full completion before freeing iser_conn.

ib_completion:
Guaranteed to come when:
- Got DISCONNECTED/ADDR_CHANGE event or
- iSCSI called ep_disconnect/conn_stop
Guaranteed to finish when:
- Got TIMEWAIT_EXIT/DEVICE_REMOVAL event
- All Flush errors are consumed
- IB related resources are destroyed

stop_completion:
Guaranteed to come when:
- iSCSI calls conn_stop
Guaranteed to finish when:
- All inflight tasks were cleaned up

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Ariel Nahum <arieln@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Fix DEVICE REMOVAL handling in the absence of iscsi daemon

iscsi daemon is in user-space, thus we can't rely on it to be invoked
at connection teardown (if not running or does not receive CPU time).

This patch addresses the issue by re-structuring iSER connection
teardown logic and CM events handling.

The CM events will dictate the RDMA resources destruction (ib_conn)
and iser_conn is kept around as long as iscsi_conn is left around
allowing iscsi/iser callbacks to continue after RDMA transport was
destroyed.

This patch introduces a separation in logic when handling CM events:

- DISCONNECTED_HANDLER, ADDR_CHANGED
This events indicate the start of teardown process.
Actions:
1. Terminate the connection: rdma_disconnect (send DREQ/DREP)
2. Notify iSCSI of connection failure
3. Change state to TERMINATING
4. Poll for all flush errors to be consumed

- TIMEWAIT_EXIT, DEVICE_REMOVAL
These events indicate the final stage of termination process and
we can free RDMA related resources.
Actions:
1. Call disconnected handler (we are not guaranteed that DISCONNECTED
event was invoked in the past)
2. Cleanup RDMA related resources
3. For DEVICE_REMOVAL return non-zero rc from cma_handler to
implicitly destroy the cm_id (Can't rely on user-space, make sure
we have forward progress)

We replace flush_completion (indicate all flushes were consumed) with
ib_completion (rdma resources were cleaned up).

The iser_conn_release_work will wait for teardown completions:

- conn_stop was completed (tasks were cleaned-up) - stop_completion
- RDMA resources were destroyed - ib_completion

And then will continue to free iser connection representation (iser_conn).

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Ariel Nahum <arieln@mellanox.com>
Signed-off-by: Roi Dayan <roid@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Extend iser_free_ib_conn_res()

Put all connection IB related resources release in this routine. One
exception is the cm_id which cannot be destroyed as the routine is
protected by the state mutex. Also move its position to avoid forward
declaration. While at it fix qp NULL assignment.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Ariel Nahum <arieln@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Re-introduce ib_conn

Structure that describes the RDMA relates connection objects. Static
member of iser_conn.

This patch does not change any functionality

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Rename ib_conn -> iser_conn

Two reasons why we choose to do this:

1. No point today calling struct iser_conn by another name ib_conn
2. In the next patches we will restructure iser control plane representation
- struct iser_conn: connection logical representation
- struct ib_conn: connection RDMA layout representation

This patch does not change any functionality.

Signed-off-by: Ariel Nahum <arieln@mellanox.com>
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Fix RX/TX CQ resource leak on error flow

When failing to allocate TX CQ we already allocated RX CQ, so we need to make
sure we release it. Also, when failing to register notification to the RX CQ
we currently leak both RX and TX CQs of the current index, fix that too.

Signed-off-by: Roi Dayan <roid@mellanox.com>
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Clarify a duplicate counters check

This is to prevent someone from thinking that this code section is
redundant.

Signed-off-by: Ariel Nahum <arieln@mellanox.com>
Signed-off-by: Roi Dayan <roid@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Replace connection waitqueue with completion object

Instead of waiting for events and condition changes of the iser
connection state, we wait for explicit completion of connection
establishment and teardown.

Separate connection establishment wait object from the teardown object
to avoid a situation where racing connection establishment and
teardown may concurrently wakeup each other.

ep_poll will wait for up_completion invoked by
iser_connected_handler() and iser release worker will wait for
flush_completion before releasing the connection.

Bound the completion wait with a 30 seconds timeout for cases where
iscsid (the user space iscsi daemon) is too slow or gone.

Signed-off-by: Ariel Nahum <arieln@mellanox.com>
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Protect iser state machine with a mutex

The iser connection state lookups and transitions are not fully protected.

Some transitions are protected with a spinlock, and in some cases the
state is accessed unprotected due to specific assumptions of the flow.

Introduce a new mutex to protect the connection state access. We use a
mutex since we need to also include a scheduling operations executed
under the state lock.

Each state transition/condition and its corresponding action will be
protected with the state mutex.

The rdma_cm events handler acquires the mutex when handling connection
events. Since iser connection state can transition to DOWN
concurrently during connection establishment, we bailout from
addr/route resolution events when the state is not PENDING.

This addresses a scenario where ep_poll retries expire during CMA
connection establishment. In this case ep_disconnect is invoked while
CMA events keep coming (address/route resolution, connected, etc...).

Signed-off-by: Ariel Nahum <arieln@mellanox.com>
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Remove redundant return code in iser_free_ib_conn_res()

Make it void.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Seperate iser_conn and iscsi_endpoint storage space

iser connection needs asynchronous cleanup completions which are
triggered in ep_disconnect. As a result we are keeping the
corresponding iscsi_endpoint structure hanging for no good reason. In
order to avoid that, we seperate iser_conn from iscsi_endpoint storage
space to have their destruction being independent.

iscsi_endpoint will be destroyed at ep_disconnect stage, while the
iser connection will wait for asynchronous completions to be released
in an orderly fashion.

Signed-off-by: Ariel Nahum <arieln@mellanox.com>
Signed-off-by: Roi Dayan <roid@mellanox.com>
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Fix responder resources advertisement

The iser initiator is the RDMA responder so it should publish to the
target the max inflight rdma read requests its local HCA can handle in
responder_resources (max_qp_rd_atom).

The iser target should take the min of that and its local HCA max
inflight oustanding rdma read requests (max_qp_init_rd_atom).

We keep initiator_depth set to 1 in order to compat with old targets.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Add TIMEWAIT_EXIT event handling

In case the DISCONNECTED event is not delivered after rdma_disconnect
is called, the CM waits TIMEWAIT seconds and delivers the
TIMEWAIT_EXIT local event. We use this as the notification needed to
continue in the teardown and release sequence.

Signed-off-by: Ariel Nahum <arieln@mellanox.com>
Signed-off-by: Roi Dayan <roid@mellanox.com>
Reviewed-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Support IPv6 address family

Replace struct sockaddr_in with struct sockaddr which supports both
IPv4 and IPv6, and print using the %pIS format directive.

Signed-off-by: Roi Dayan <roid@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Fix a possible race in iser connection states transition

In some circumstances (multiple targets), RDMA_CM ESTABLISHED event
and ep_disconnect may race. In this case, the iser connection state
may transition to UP (after ep_disconnect transitioned it to
TERMINATING), while the connection is being torn down.

Upon RDMA_CM event ESTABLISHED we allow iser connection state to
transition to UP only from PENDING. We also make sure to protect this
state change (done under the connection lock).

Signed-off-by: Ariel Nahum <arieln@mellanox.com>
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Reviewed-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Simplify connection management

iSER relies on refcounting to manage iser connections establishment
and teardown.

Following commit 39ff05dbbbdb ("IB/iser: Enhance disconnection logic
for multi-pathing"), iser connection maintain 3 references:

- iscsi_endpoint (at creation stage)
- cma_id (at connection request stage)
- iscsi_conn (at bind stage)

We can avoid taking explicit refcounts by correctly serializing iser
teardown flows (graceful and non-graceful).

Our approach is to trigger a scheduled work to handle ordered teardown
by gracefully waiting for 2 cleanup stages to complete:

1. Cleanup of live pending tasks indicated by iscsi_conn_stop completion
2. Flush errors processing

Each completed stage will notify a waiting worker thread when it is
done to allow teardwon continuation.

Since iSCSI connection establishment may trigger endpoint disconnect
without a successful endpoint connect, we rely on the iscsi <-> iser
binding (.conn_bind) to learn about the teardown policy we should take
wrt cleanup stages.

Since all cleanup worker threads are scheduled (release_wq) in
.ep_disconnect it is safe to assume that when module_exit is called,
all cleanup workers are already scheduled. Thus proper module unload
shall flush all scheduled works before allowing safe exit, to
guarantee no resources got left behind.

Signed-off-by: Ariel Nahum <arieln@mellanox.com>
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Reviewed-by: Roi Dayan <roid@mellanox.com>
Reviewed-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Update Mellanox copyright note

Update Mellanox copyrights for 2014 on the iser initiator driver.

Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Print QP information once connection is established

Add an iser info print with the local/remote QP information carried
out when the connection is established. While here, fix a little
leftover from the T10 work and set a debug print to be carried in
debug and not info level.

Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Remove struct iscsi_iser_conn

The iscsi stack has existing mechanisms to link back and forth between
the iscsi connection and the iscsi transport (e.g iser/tcp) connection.

This is done through a dd_data pointer field in struct iscsi_conn
which can be set to point to the transport connection, etc.

The iscsi_iser_conn structure was used to get this linking done in
another way, which is uneeded and adds extra complication to the iser
code, so we just remove it.

Signed-off-by: Ariel Nahum <arieln@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Drain the tx cq once before looping on the rx cq

The iser disconnection flow isn't done before all the inflight
recv/send buffers posted to the QP are either flushed or normally
completed to the CQ that serves this connection. The condition check
is done in iser_handle_comp_error().

Currently, it's possible for the send buffer completion that makes the
posted send buffers counter reach zero to be polled in the drain tx
call, which is after the rx cq is fully drained. Since this
completion might be not an error one (for example, it might be a
completion of the logout request iSCSI PDU) we will skip
iser_handle_comp_error(). So the connection will never terminate from
the iscsi stack point of view, and we hang.

To resolve this race, do the draining of the tx cq before the loop on
the rx cq.

Signed-off-by: Roi Dayan <roid@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Fix sector_t format warning

Fix pr_err (printk) format warning:

drivers/infiniband/ulp/iser/iser_verbs.c:1181:4: warning: format '%lx' expects argument of type 'long unsigned int', but argument 3 has type 'sector_t' [-Wformat]

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Implement check_protection

Once the iSCSI transaction is completed we must implement
check_protection in order to notify on DIF errors that may have
occured.

The routine boils down to calling ib_check_mr_status to get the
signature status of the transaction.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Alex Tabachnik <alext@mellanox.com>

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Initialize T10-PI resources

During connection establishment we also initialize T10-PI resources
(QP, PI contexts) in order to support SCSI's protection operations.

Signed-off-by: Alex Tabachnik <alext@mellanox.com>
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Introduce pi_enable, pi_guard module parameters

Use modparams to activate protection information support.

pi_enable bool: Based on this parameter iSER will know if it should
support T10-PI. We don't want to do this by default as it requires to
allocate and initialize extra resources. In case pi_enable=N, iSER
won't publish to SCSI midlayer any DIF capabilities.

pi_guard int: Based on this parameter iSER will publish DIX guard type
support to SCSI midlayer. 0 means CRC is allowed to be passed in DIX
buffers, 1 (or non-zero) means IP-CSUM is allowed to be passed in DIX
buffers. Note that over the wire, only CRC is allowed.

In the next phase, it is worth considering passing these parameters
from iscsid via nlmsg. This will allow these parameters to be
connection based rather than global.

Signed-off-by: Alex Tabachnik <alext@mellanox.com>
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Replace fastreg descriptor valid bool with indicators container

In T10-PI support we will have memory keys for protection buffers and
signature transactions. We prefer to compact indicators rather than
keeping multiple bools.

This commit does not change any functionality.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Alex Tabachnik <alext@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Keep IB device attributes under iser_device

For T10-PI offload support, we will need to know the device signature
offload capability upon every connection establishment.

This patch does not change any functionality.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Alex Tabachnik <alext@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Move fast_reg_descriptor initialization to a function

fastreg descriptor will include protection information context. In
order to place the logic in one place we introduce iser_create_fr_desc
function.

This patch does not change any functionality.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Alex Tabachnik <alext@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Avoid FRWR notation, use fastreg instead

FRWR stands for "fast registration work request". We want to avoid
calling the fastreg pool with that name, instead we name it fastreg
which stands for "fast registration".

This pool will include more elements in the future, so it is a good
idea to generalize the name.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Alex Tabachnik <alext@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Suppress completions for fast registration work requests

In case iSER uses fast registration method, it should not request for
successful completions on fast registration nor local invalidate
requests. We color wr_id with ISER_FRWR_LI_WRID in order to correctly
consume error completions.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Avoid dereferencing iscsi_iser conn object when not bound to iser connection

Fix a possible NULL pointer dereference in disconnection flow. This
can happen if the target disconnected/rejected the connection request,
e.g before the binding stage between iscsi connection to the transport
connection.

Signed-off-by: Alex Tabachnik <alext@mellanox.com>
Signed-off-by: Roi Dayan <roid@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Fix possible memory leak in iser_create_frwr_pool()

Fix leak where desc is not being freed in error flows.

Signed-off-by: Roi Dayan <roid@mellanox.com>
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Introduce fast memory registration model (FRWR)

Newer HCAs and Virtual functions may not support FMRs but rather a fast
registration model, which we call FRWR - "Fast Registration Work Requests".

This model was introduced in 00f7ec36c ("RDMA/core: Add memory management
extensions support") and works when the IB device supports the
IB_DEVICE_MEM_MGT_EXTENSIONS capability.

Upon creating the iser device iser will test whether the HCA supports
FMRs. If no support for FMRs, check if IB_DEVICE_MEM_MGT_EXTENSIONS
is supported and assign function pointers that handle fast
registration and allocation of appropriate resources (fast_reg
descriptors).

Registration is done using posting IB_WR_FAST_REG_MR to the QP and
invalidations using posting IB_WR_LOCAL_INV.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Place the fmr pool into a union in iser's IB conn struct

This is preparation step for other memory registration methods to be
added. In addition, change reg/unreg routines signature to indicate
they use FMRs.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Generalize rdma memory registration

Currently the driver uses FMRs as the only means to register the
memory pointed by SG provided by the SCSI mid-layer with the RDMA
device.

As preparation step for adding more methods for fast path memory
registration, make the alloc/free and reg/unreg calls function
pointers, which are for now just set to the existing FMR ones.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Accept session->cmds_max from user space

Use cmds_max passed from user space to be the number of PDUs to be
supported for the session instead of hard-coded ISCSI_DEF_XMIT_CMDS_MAX.
This allow controlling the max number of SCSI commands for the session.
Also don't ignore the qdepth passed from user space.

Derive from session->cmds_max the actual number of RX buffers and FMR
pool size to allocate during the connection bind phase.

Since the iser transport connection is established before the iscsi
session/connection are created and bound, we still use one hard-coded
quantity ISER_DEF_XMIT_CMDS_MAX to compute the maximum number of
work-requests to be supported by the RC QP used for the connection.

The above quantity is made to be a power of two between ISCSI_TOTAL_CMDS_MIN
(16) and ISER_DEF_XMIT_CMDS_MAX (512) inclusive.

Signed-off-by: Shlomo Pongratz <shlomop@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Restructure allocation/deallocation of connection resources

This is a preparation step to a patch that accepts the number of max
SCSI commands to be supported a session from user space iSCSI tools.

Move the allocation of the login buffer, FMR pool and its associated
page vector from iser_create_ib_conn_res() (which is called prior when
we actually know how many commands should be supported) to
iser_alloc_rx_descriptors() (which is called during the iscsi
connection bind step where this quantity is known).

Also do small refactoring around the deallocation to make that path
similar to the allocation one.

Signed-off-by: Shlomo Pongratz <shlomop@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Add Mellanox copyright

Add Mellanox copyright to the iser initiator source code which I maintain.

Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Fix device removal flow

Change the code to destroy the "last opened" rdma_cm id after making
sure we released all other objects (QP, CQs, PD, etc) associated with
the IB device.

Since iser accesses the IB device using the rdma_cm id, we need to
free any objects that are related to the device that is associated
with the rdma_cm id prior to destroying that id. When this isn't
done, the low level driver that created this device can be unloaded
before iser has a chance to free all the objects and a such a call may
invoke code segment which isn't valid any more and crash.

Cc: Sean Hefty <sean.hefty@intel.com
Signed-off-by: Roi Dayan <roid@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Add support for iser CM REQ additional info

Annex A12 of the IBTA spec defines additional information that needs
to be provided through the CM exchange relating to usage of ZBVA (Zero
Based VAs) and Send With Invalidate over an iSER connection.

Currently, the initiator sets both to not supported, but does provide
the header so that existing iSER targets can be patched to start
looking on the private data carried by the CM.

This is a preparation step to enable iSER with HW drivers for which
FMRs are not supported, such as mlx4 VF instances or new HW devices
which might support only FRWR (Fast Registration Work-Requests) along
the details of the IB_DEVICE_MEM_MGT_EXTENSIONS device capability.

Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Move informational messages from error to info level

Introduce iser_info() and move informational messages that were
printed as errors to use that macro. Also, cleanup printk leftovers to
use the existing macros.

Signed-off-by: Roi Dayan <roid@mellanox.com>
Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>

[ Use pr_warn(... instead of printk(KERN_WARNING .... - Roland ]

Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Enable iser when FMRs are not supported

Reuse the "SG unaligned for FMR" driver flow to make the initiator
functional when running over driver instance which doesn't support
FMRs, such as a mlx4 virtual function.

Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Alex Tabachnik <alext@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Add more RX CQs to scale out processing of SCSI responses

RX/TX CQs will now be selected from a per HCA pool. For the RX flow
this has the effect of using different interrupt vectors when using
low level drivers (such as mlx4) that map the "vector" param provided
by the ULP on CQ creation to a dedicated IRQ/MSI-X vector. This
allows the RX flow processing of IO responses to be distributed across
multiple CPUs.

QPs (--> iSER sessions) are assigned to CQs in round robin order using
the CQ with the minimum number of sessions attached to it.

Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Alex Tabachnik <alext@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Fix error flow in iser ep connection establishment

The current error flow code was releasing the IB connection object and
calling iscsi_destroy_endpoint() directly without going through the
reference counting mechanism introduced in commit 39ff05d ("IB/iser:
Enhance disconnection logic for multi-pathing"). This resulted in a
double free of the iscsi endpoint object, which causes a kernel NULL
pointer dereference. Fix that by plugging into the IB conn reference
counting correctly.

Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Free IB connection resources in the proper place

We allocate the login dma buffers in iser_verbs.c as part of
alloc_ib_conn_resources(), however we are freeing them in
iser_initiator.c as part of iser_free_rx_descriptors(). This is
needlessly confusing. We have an alloc_rx_descriptors() and it
doesn't alloc something that the free_rx_descriptors() frees, and we
have an alloc_ib_conn_resources() that allocs something not freed by
free_ib_conn_resources(). Clean that up.

Signed-off-by: Doug Ledford <dledford@redhat.com>

[ Fix build error in iser_free_ib_conn_res(). - Or ]

Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Use separate buffers for the login request/response

The driver counted on the transactional nature of iSCSI login/text
flows and used the same buffer for both the request and the response.
We also went further and did DMA mapping only once, with
DMA_FROM_DEVICE, which violates the DMA mapping API. Fix that by
using different buffers, one for requests and one for responses, and
use the correct DMA mapping direction for each.

Signed-off-by: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

RDMA/cma: Pass QP type into rdma_create_id()

The RDMA CM currently infers the QP type from the port space selected
by the user. In the future (eg with RDMA_PS_IB or XRC), there may not
be a 1-1 correspondence between port space and QP type. For netlink
export of RDMA CM state, we want to export the QP type to userspace,
so it is cleaner to explicitly associate a QP type to an ID.

Modify rdma_create_id() to allow the user to specify the QP type, and
use it to make our selections of datagram versus connected mode.

Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <roland@purestorage.com>

IB/iser: Fix error flow in iser_create_ib_conn_res()

We shouldn't free things here because we free them later.
The call tree looks like this:
iser_connect() ==> initiating the connection establishment
and later
iser_cma_handler() => iser_route_handler() => iser_create_ib_conn_res()
if we fail here, eventually iser_conn_release() is called, resulting
in a double free.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Or Gerlitz <ogerlitz@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

IB/iser: Enhance disconnection logic for multi-pathing

The iser connection teardown flow isn't over until the underlying
Connection Manager (e.g the IB CM) delivers a disconnected or timeout
event through the RDMA-CM. When the remote (target) side isn't
reachable, e.g when some HW e.g port/hca/switch isn't functioning or
taken down administratively, the CM timeout flow is used and the event
may be generated only after relatively long time -- on the order of
tens of seconds.

The current iser code exposes this possibly long delay to higher
layers, specifically to the iscsid daemon and iscsi kernel stack. As a
result, the iscsi stack doesn't respond well: this low-level CM delay
is added to the fail-over time under HA schemes such as the one
provided by DM multipath through the multipathd(8) service.

This patch enhances the reference counting scheme on iser's IB
connections so that the disconnect flow initiated by iscsid from user
space (ep_disconnect) doesn't wait for the CM to deliver the
disconnect/timeout event. (The connection teardown isn't done from
iser's view point until the event is delivered)

The iser ib (rdma) connection object is destroyed when its reference
count reaches zero. When this happens on the RDMA-CM callback
context, extra care is taken so that the RDMA-CM does the actual
destroying of the associated ID, since doing it in the callback is
prohibited.

The reference count of iser ib connection normally reaches three,
where the <ref, deref> relations are

1. conn <init, terminate>
2. conn <bind, stop/destroy>
3. cma id <create, disconnect/error/timeout callbacks>

With this patch, multipath fail-over time is about 30 seconds, while
without this patch, multipath fail-over time is about 130 seconds.

Signed-off-by: Or Gerlitz <ogerlitz@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

IB/iser: Remove buggy back-pointer setting

The iscsi connection object life cycle includes binding and unbinding
(conn_stop) to/from the iscsi transport connection object. Since
iscsi connection objects are recycled, at the time the transport
connection (e.g iser's IB connection) is released, it is not valid to
touch the iscsi connection tied to the transport back-pointer since it
may already point to a different transport connection.

Signed-off-by: Or Gerlitz <ogerlitz@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

IB/iser: Add asynchronous event handler

Add handler to handle events such as port up and down. This is useful
when testing high-availability schemes such as multi-pathing.

Signed-off-by: Or Gerlitz <ogerlitz@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.

2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).

* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

IB/iser: Remove unnecessary connection checks

Remove unnecessary checks for the IB connection state and for QP
overflow, as conn state changes are reported by iSER to libiscsi and
handled there. QP overflow is theoretically possible only when
unsolicited data-outs are used; anyway it's being checked and handled
by HW drivers.

Signed-off-by: Or Gerlitz <ogerlitz@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

IB/iser: Simplify send flow/descriptors

Simplify and shrink the logic/code used for the send descriptors.
Changes include removing struct iser_dto (an unnecessary abstraction),
using struct iser_regd_buf only for handling SCSI commands, using
dma_sync instead of dma_map/unmap, etc.

Signed-off-by: Or Gerlitz <ogerlitz@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

IB/iser: Use different CQ for send completions

Use a different CQ for send completions, where send completions are
polled by the interrupt-driven receive completion handler. Therefore,
interrupts aren't used for the send CQ.

Signed-off-by: Or Gerlitz <ogerlitz@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

IB/iser: Remove atomic counter for posted receive buffers

Now that both the posting and reaping of receive buffers is done in
the completion path, the counter of outstanding buffers not be atomic.

Signed-off-by: Or Gerlitz <ogerlitz@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

IB/iser: New receive buffer posting logic

Currently, the recv buffer posting logic is based on the transactional
nature of iSER which allows for posting a buffer before sending a PDU.
Change this to post only when the number of outstanding recv buffers
is below a water mark and in a batched manner, thus simplifying and
optimizing the data path. Use a pre-allocated ring of recv buffers
instead of allocating from kmem cache. A special treatment is given
to the login response buffer whose size must be 8K unlike the size of
buffers used for any other purpose which is 128 bytes.

Signed-off-by: Or Gerlitz <ogerlitz@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

IB/iser: Revert commit bba7ebb "avoid recv buffer exhaustion"

We will make a major change in the recv buffer posting logic, after
which the problem commit bba7ebb "avoid recv buffer exhaustion caused
by unexpected PDUs" comes to solve doesn't exist any more, so revert it.

Signed-off-by: Or Gerlitz <ogerlitz@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

tree-wide: fix some typos and punctuation in comments

fix some typos and punctuation in comments

Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

IB/iser: Remove hard setting of path MTU

Remove hard setting of the IB MTU used by iSER's RC queue-pair to 1K,
as this was done due to inter-op issues with an old iser target which
is not used any more.

Signed-off-by: Or Gerlitz <ogerlitz@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

IB/iser: Avoid recv buffer exhaustion caused by unexpected PDUs

iSCSI/iSER targets may send PDUs without a prior request from the
initiator. RFC 5046 refers to these PDUs as "unexpected". NOP-In PDUs
with itt=RESERVED and Asynchronous Message PDUs occupy this category.

The amount of active "unexpected" PDU's an iSER target may have at any
time is governed by the MaxOutstandingUnexpectedPDUs key, which is not
yet supported.

Currently when an iSER target sends an "unexpected" PDU, the
initiators recv buffer consumed by the PDU is not replaced. If over
initial_post_recv_bufs_num "unexpected" PDUs are received then the
receive queue will run out of receive work requests entirely.

This patch ensures recv buffers consumed by "unexpected" PDUs are
replaced in the next iser_post_receive_control() call.

Signed-off-by: David Disseldorp <ddiss@sgi.com>
Signed-off-by: Ken Sandars <ksandars@sgi.com>
Acked-by: Or Gerlitz <ogerlitz@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

drivers: replace NIPQUAD()

Using NIPQUAD() with NIPQUAD_FMT, %d.%d.%d.%d or %u.%u.%u.%u
can be replaced with %pI4

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

removed unused #include <linux/version.h>'s

This patch lets the files using linux/version.h match the files that
#include it.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

IB/iser: Add support for RDMA_CM_EVENT_ADDR_CHANGE event

Enhance iser to act upon notification on network stack changes that
make its RDMA connection unaligned with the link used by the stack for
the <src,dst> IPs used to establish the connection.

When RDMA_CM_EVENT_ADDR_CHANGE arrives, just disconnect the
connection, assuming that the user space iscsid daemon will reconnect,
and the new connection will be aligned with the IP stack.

Signed-off-by: Or Gerlitz <ogerlitz@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

RDMA: Remove subversion $Id tags

They don't get updated by git and so they're worse than useless.

Signed-off-by: Roland Dreier <rolandd@cisco.com>

[SCSI] iser: Modify iser to take a iscsi_endpoint struct in ep callouts and session setup

This hooks iser into the iscsi endpoint code. Previously it handled the
lookup and allocation. This has been made generic so bnx2i and iser can
share it. It also allows us to pass iser the leading conn's ep, so we
know the ib_deivce being used and can set it as the scsi_host's parent.
And that allows scsi-ml to set the dma_mask based on those values.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

[SCSI] iser: fix handling of scsi cmnds during recovery.

After the stop_conn callback has returned the LLD should not
touch the scsi cmds. iscsi_tcp and libiscsi use the
conn->recv_lock and suspend_rx field to halt recv path
processing, but iser does not have any protection.

This patch modifies iser so that userspace can just
call the ep_disconnect callback, which will halt
all recv IO, before calling the stop_conn callback so
we do not have to worry about the conn->recv_lock and
suspend rx field. iser just needs to stop the send side
from accessing the ib conn.

Fixup to handle when the ep poll fails and ep disconnect
is called from Erez.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

IB/iser: Release connection resources on RDMA_CM_EVENT_DEVICE_REMOVAL event

When a RDMA_CM_EVENT_DEVICE_REMOVAL event is raised, iSER should
release the connection resources.

This is necessary when the IB HCA module is unloaded while open-iscsi
is still running. Currently, iSER just BUG()s.

Signed-off-by: Erez Zilber <erezz@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

IB/iser: Handle iser_device allocation error gracefully

"iser_device" allocation failure is "handled" with a BUG_ON() right
before dereferencing the NULL-pointer - fix this!

Signed-off-by: Arne Redlich <arne.redlich@xiranet.com>
Signed-off-by: Erez Zilber <erezz@voltaire.com>

IB/iser: Fix list iteration bug

The iteration through the list of "iser_device"s during device
lookup/creation is broken -- it might result in an infinite loop if
more than one HCA is used with iSER. Fix this by using
list_for_each_entry() instead of the open-coded flawed list iteration
code.

Signed-off-by: Arne Redlich <arne.redlich@xiranet.com>
Signed-off-by: Erez Zilber <erezz@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

IB/iser: Print information about unhandled RDMA CM events

Some RDMA CM events are not supported or not handled in iSER.
This patch adds some info (printk) for the user about them.

Signed-off-by: Erez Zilber <erezz@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

IB/iser: Typo fix (s/destory/destroy/)

Signed-off-by: Oliver Pinter <oliver.pntr@gmail.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

IB/iser: Remove unnecessary includes

<asm/scatterlist.h> is not needed because everyplace it appears,
<linux/scatterlist.h> also appears. <asm/io.h> is not needed because
nothing seems to be using device IO anyway.

Signed-off-by: Roland Dreier <rolandd@cisco.com>

IB/iser: Make a couple of functions static

Make iser_conn_release() and iser_start_rdma_unaligned_sg() static,
since they are only used in the .c file where they are defined. In
addition to being a cleanup, this even shrinks the generated code by
allowing the single call of iser_start_rdma_unaligned_sg() to be
inlined into its callsite. On x86_64:

add/remove: 0/1 grow/shrink: 1/0 up/down: 466/-533 (-67)
function old new delta
iser_reg_rdma_mem 1518 1984 +466
iser_start_rdma_unaligned_sg 533 - -533

Signed-off-by: Roland Dreier <rolandd@cisco.com>

[SCSI] libiscsi: make can_queue configurable

This patch allows us to set can_queue and cmds_per_lun from userspace
when we create the session/host. From there we can set it on a per
target basis. The patch fully converts iscsi_tcp, but only hooks
up ib_iser for cmd_per_lun since it currently has a lots of preallocations
based on can_queue.

Signed-off-by: Mike Christie <michaelc@cs.wisc.edu>
Cc: Roland Dreier <rdreier@cisco.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

header cleaning: don't include smp_lock.h when not used

Remove includes of <linux/smp_lock.h> where it is not used/needed.
Suggested by Al Viro.

Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc,
sparc64, and arm (all 59 defconfigs).

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

IB: Add CQ comp_vector support

Add a num_comp_vectors member to struct ib_device and extend
ib_create_cq() to pass in a comp_vector parameter -- this parallels
the userspace libibverbs API. Update all hardware drivers to set
num_comp_vectors to 1 and have all ULPs pass 0 for the comp_vector
value. Pass the value of num_comp_vectors to userspace rather than
hard-coding a value of 1.

We want multiple CQ event vector support (via MSI-X or similar for
adapters that can generate multiple interrupts), but it's not clear
how many vectors we want, or how we want to deal with policy issues
such as how to decide which vector to use or how to set up interrupt
affinity. This patch is useful for experimenting, since no core
changes will be necessary when updating a driver to support multiple
vectors, and we know that we want to make at least these changes
anyway.

Signed-off-by: Michael S. Tsirkin <mst@dev.mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

IB/iser: Don't defer connection failure notification to workqueue

When a connection is terminated asynchronously from the iSCSI layer's
perspective, iSER needs to notify the iSCSI layer that the connection
has failed. This is done using a workqueue (switched to from the iSER
tasklet context). Meanwhile, the connection object (that holds the
work struct) is released. If the workqueue function wasn't called
yet, it will be called later with a NULL pointer, which will crash the
kernel.

The context switch (tasklet to workqueue) is not required, and
everything can be done from the iSER tasklet. This eliminates the NULL
work struct bug (and simplifies the code).

Signed-off-by: Erez Zilber <erezz@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

WorkStruct: make allyesconfig

Fix up for make allyesconfig.

Signed-Off-By: David Howells <dhowells@redhat.com>

IB/iser: Have iSER data transaction object point to iSER conn

iSER uses a data transaction object (struct iser_dto) as part
of its IB data descriptors (struct iser_desc) management.
It also uses a hierarchy of connection structures pointing to
each other. A DTO may exist even after the iscsi_iser connection
pointed by it is destroyed (eg one that is bound to a post
receive buffer which was flushed by the IB HW). Hence DTOs need
point to the lowest connection, which is struct iser_conn.

Signed-off-by: Erez Zilber <erezz@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

IB/iser: Do not use FMR for a single dma entry sg

Fast Memory Registration (fmr) is used to register for rdma an sg whose
elements are not linearly sequential after dma mapping.

The IB verbs layer provides an "all dma memory MR (memory region)" which
can be used for RDMA-ing a dma linearly sequential buffer.

Change the code to use the dma mr instead of doing fmr when dma mapping
produces a single dma entry sg.

Signed-off-by: Erez Zilber <erezz@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

IB/iser: make FMR "page size" be 4K and not PAGE_SIZE

As iser is able to use at most one rdma operation for the
execution of a scsi command, and registration of the sg
associated with scsi command has its restrictions, the code
checks if an sg is "aligned for rdma".

Alignment for rdma is measured in "fmr page" units whose
possible resolutions are different between HCAs and can be
smaller, equal or bigger to the system page size.

When the system page size is bigger than 4KB (eg the default
with ia64 kernels) there a bigger chance that an sg would be
aligned for rdma if the fmr page size is 4KB.

Change the code to create FMR whose pages are of size 4KB
and to take that into account when processing the sg.

Signed-off-by: Erez Zilber <erezz@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

[PATCH] fmr pool: remove unnecessary pointer dereference

ib_fmr_pool_map_phys gets the virtual address by pointer but never writes
there, and users (e.g. srp) seem to assume this and ignore the value
returned. This patch cleans up the API to get the VA by value, and updates
all users.

Signed-off-by: Michael S. Tsirkin <mst@mellanox.co.il>
Acked-by: Roland Dreier <rolandd@cisco.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

IB/iser: iSER RDMA CM (CMA) and IB verbs interaction

This file contains the low level interaction with the RDMA CM
and the IB verbs, where iSER is consumer of both.

Signed-off-by: Or Gerlitz <ogerlitz@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>