Combination of CONFIG_DEBUG_OBJECTS_RCU_HEAD=y and
CONFIG_INFINIBAND_SRPT=m produces the following build error.

ERROR: "init_rcu_head" [drivers/infiniband/ulp/srpt/ib_srpt.ko] undefined!
make[1]: *** [scripts/Makefile.modpost:92: __modpost] Error 1
make: *** [Makefile:1216: modules] Error 2

The reason to it that init_rcu_head() is not exported and not supposed
to be used in modules. It is needed for dynamic initialization of
statically allocated rcu_head structures.

Fixes: 795bc112 ("IB/srpt: Make it safe to use RCU for srpt_device.rch_list")
Fixes: a1125314 ("IB/srpt: Rework multi-channel support")
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: NLeon Romanovsky <leonro@mellanox.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

This patch does not change any functionality but makes srpt_cm_req_recv()
independent of the IB/CM and hence simplifies the patch that introduces
RDMA/CM support.
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Introduce a union in struct srpt_rdma_ch for member variables that
depend on the type of connection manager. Avoid that error messages
report the IB/CM ID.
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

If a receive I/O context is removed from the wait list and
srpt_handle_new_iu() fails to allocate a send I/O context then
re-adding the receive I/O context to the wait list can cause
reordering. Avoid this by only removing a receive I/O context
from the wait list after allocating a send I/O context succeeded.
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Wait list processing only occurs if the channel state >= CH_LIVE. Hence
set the channel state to CH_LIVE before triggering wait list processing
asynchronously.
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Make sure that sport->mutex is not released between the duplicate
channel check, adding a channel to the channel list and performing
the sport enabled check. Avoid that srpt_disconnect_ch() can be
invoked concurrently with the ib_send_cm_rep() call by
srpt_cm_req_recv().
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

The new pr_debug() statements are useful when debugging the ib_srpt
driver.
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Move a mutex lock and unlock statement from srpt_close_session()
into srpt_disconnect_ch_sync(). Since the previous patch removed
the last user of the return value of that function, change the
return value of srpt_disconnect_ch_sync() into void.
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Store initiator and target port ID's once per nexus instead of in each
channel data structure. This change simplifies the duplicate connection
check in srpt_cm_req_recv().
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Use the source GID as session name instead of the initiator port ID
from the SRP login request. The only functional change in this patch
is that it changes the session name shown in debug messages.

Note: the fifth argument that is passed to target_alloc_session() is
what the SCSI target core uses as key for lookups in the ACL (access
control list) information.
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

In multipathing setups where a target system is equipped with
dual-port HCAs it is useful to have one connection per target port
instead of one connection per target HCA. Hence move the connection
list (rch_list) from struct srpt_device into struct srpt_port.
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Process connection requests that use another P_Key than the default
correctly.
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

This patch fixes a use-after-free issue for ch->release_done when
running the SRP protocol on top of the rdma_rxe driver.
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

The next patch will iterate over rch_list from a context from which
it is not allowed to block. Hence make rch_list RCU-safe.
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Since all I/O context state changes are already serialized, it is
not necessary to protect I/O context state changes with the I/O
context spinlock. Hence remove that spinlock.
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

It is not necessary to obtain ioctx->spinlock when reading the ioctx
state. Since after removal of this locking only a single line remains,
inline the srpt_get_cmd_state() function.
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Introduce a function for converting a GUID into an ASCII string. This
patch does not change any functionality.
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Disabling an SRP target port causes the state of all QPs associated
with a port to be changed into IB_QPS_ERR. Avoid that this causes
one error message per I/O context to be reported.
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

At least when running the ib_srpt driver on top of the rdma_rxe
driver it is easy to trigger a zero-length write completion in
the CH_DISCONNECTED state. Hence make the message that reports
this less noisy.
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Make the ib_srpt driver use the IPv6 format for GIDs in log messages
to improve consistency of this driver with other RDMA kernel drivers.
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Verify whether port numbers are in the expected range before using
these as an array index. Complain if a port number is out of range.
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Since the SRQ event message is only useful for debugging purposes,
reduce its severity from "informational" to "debug".
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Rename rsp_size into max_rsp_size and SRPT_RQ_SIZE into MAX_SRPT_RQ_SIZE.
The new names better reflect the role of this member variable and constant.
Since the prefix "srp_" is superfluous in the context of the function
that creates an RDMA channel, rename srp_sq_size into sq_size.
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Avoid that warnings about missing parameter descriptions are reported
when building with W=1.
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Fixes: commit a42d985b ("ib_srpt: Initial SRP Target merge for v3.3-rc1")
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Make sure that the initiator port GUID is stored in ch->ini_guid.
Note: when initiating a connection sgid and dgid members in struct
sa_path_rec represent the source and destination GIDs. When accepting
a connection however sgid represents the destination GID and dgid the
source GID.

Fixes: commit 2bce1a6d ("IB/srpt: Accept GUIDs as port names")
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

With the SRP protocol all RDMA operations are initiated by the target.
Since no RDMA operations are initiated by the initiator, do not grant
the initiator permission to submit RDMA reads or writes to the target.
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NJason Gunthorpe <jgg@mellanox.com>

The use_srq configfs attribute is created after it is read. Hence
modify srpt_tpg_attrib_use_srq_store() such that this function
switches dynamically between non-SRQ and SRQ mode.
Reported-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Introduce the helper function srpt_set_enabled(). Protect
sport->enabled changes with sdev->mutex. Makes configfs writes
into 'enabled' wait until all channel resources have been freed.
Wait until channel release has finished during kernel module
unload.
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Except for changing a BUG_ON() call into a WARN_ON_ONCE() call, this
patch does not change any functionality.
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

The only functional change in this patch is in the srpt_add_one()
error path: if allocating the ring buffer for the SRQ fails, fall
back to non-SRQ mode instead of disabling SRP target functionality.
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

IB and iWARP specs both spell out that posting a receive work request
to a queue pair in the RESET state is an invalid operation and required
to fail.  Postpone posting receive work requests until after the
transition to the INIT state.

Fixes: commit dea26209 ("IB/srpt: Change default behavior from using SRQ to using RC")
Signed-off-by: NMike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Several function prototypes for the set/get functions defined by
module_param_call() have a slightly wrong argument types. This fixes
those in an effort to clean up the calls when running under type-enforced
compiler instrumentation for CFI. This is the result of running the
following semantic patch:

@match_module_param_call_function@
declarer name module_param_call;
identifier _name, _set_func, _get_func;
expression _arg, _mode;
@@

 module_param_call(_name, _set_func, _get_func, _arg, _mode);

@fix_set_prototype
 depends on match_module_param_call_function@
identifier match_module_param_call_function._set_func;
identifier _val, _param;
type _val_type, _param_type;
@@

 int _set_func(
-_val_type _val
+const char * _val
 ,
-_param_type _param
+const struct kernel_param * _param
 ) { ... }

@fix_get_prototype
 depends on match_module_param_call_function@
identifier match_module_param_call_function._get_func;
identifier _val, _param;
type _val_type, _param_type;
@@

 int _get_func(
-_val_type _val
+char * _val
 ,
-_param_type _param
+const struct kernel_param * _param
 ) { ... }

Two additional by-hand changes are included for places where the above
Coccinelle script didn't notice them:

	drivers/platform/x86/thinkpad_acpi.c
	fs/lockd/svc.c
Signed-off-by: NKees Cook <keescook@chromium.org>
Signed-off-by: NJessica Yu <jeyu@kernel.org>

Although in the RC mode more resources are needed that mode has three
advantages over SRQ:
- It works with all RDMA adapters, even those that do not support
  SRQ.
- Posting WRs and polling WCs does not trigger lock contention
  because only one thread at a time accesses a WR or WC queue in
  non-SRQ mode.
- The end-to-end flow control mechanism is used.

>From the IB spec:

    C9-150.2.1: For QPs that are not associated with an SRQ, each HCA
    receive queue shall generate end-to-end flow control credits. If
    a QP is associated with an SRQ, the HCA receive queue shall not
    generate end-to-end flow control credits.

Add new configfs attributes that allow to configure which mode to use
(/sys/kernel/config/target/srpt/$GUID/$GUID/attrib/use_srq). Note:
only the attribute for port 1 is relevant on multi-port adapters.
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

This patch is a micro-optimization for the hot path.
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Additionally, correct the comment about ch->rq_size.
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Make srpt_parse_i_port_id() return a negative value if hex2bin()
fails.

Fixes: commit a42d985b ("ib_srpt: Initial SRP Target merge for v3.3-rc1")
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

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: NLeon Romanovsky <leonro@mellanox.com>
Reviewed-by: NDennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: NDoug Ledford <dledford@redhat.com>

Do not only report the state of the I/O context before srpt_abort_cmd()
was called but also the new state assigned by srpt_abort_cmd()
Signed-off-by: NBart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Cc: Doug Ledford <dledford@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Andy Grover <agrover@redhat.com>
Cc: David Disseldorp <ddiss@suse.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>

Avoid that the following warning is triggered:

WARNING: CPU: 10 PID: 166 at ../drivers/infiniband/ulp/srpt/ib_srpt.c:2674 srpt_release_cmd+0x139/0x140 [ib_srpt]
CPU: 10 PID: 166 Comm: kworker/u24:8 Not tainted 4.9.4-1-default #1
Workqueue: tmr-fileio target_tmr_work [target_core_mod]
Call Trace:
 [<ffffffffaa3c4f70>] dump_stack+0x63/0x83
 [<ffffffffaa0844eb>] __warn+0xcb/0xf0
 [<ffffffffaa0845dd>] warn_slowpath_null+0x1d/0x20
 [<ffffffffc06ba429>] srpt_release_cmd+0x139/0x140 [ib_srpt]
 [<ffffffffc06e4377>] target_release_cmd_kref+0xb7/0x120 [target_core_mod]
 [<ffffffffc06e4d7f>] target_put_sess_cmd+0x2f/0x60 [target_core_mod]
 [<ffffffffc06e15e0>] core_tmr_lun_reset+0x340/0x790 [target_core_mod]
 [<ffffffffc06e4816>] target_tmr_work+0xe6/0x140 [target_core_mod]
 [<ffffffffaa09e4d3>] process_one_work+0x1f3/0x4d0
 [<ffffffffaa09e7f8>] worker_thread+0x48/0x4e0
 [<ffffffffaa09e7b0>] ? process_one_work+0x4d0/0x4d0
 [<ffffffffaa0a46da>] kthread+0xca/0xe0
 [<ffffffffaa0a4610>] ? kthread_park+0x60/0x60
 [<ffffffffaa71b775>] ret_from_fork+0x25/0x30
Signed-off-by: NBart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Cc: Doug Ledford <dledford@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Disseldorp <ddiss@suse.de>
Signed-off-by: NNicholas Bellinger <nab@linux-iscsi.org>