linux-toradex.git/include/target/iscsi, branch v4.12

iscsi-target: Fix initial login PDU asynchronous socket close OOPs

2017-05-31T22:12:31+00:00

This patch fixes a OOPs originally introduced by:

   commit bb048357dad6d604520c91586334c9c230366a14
   Author: Nicholas Bellinger 
   Date:   Thu Sep 5 14:54:04 2013 -0700

   iscsi-target: Add sk->sk_state_change to cleanup after TCP failure

which would trigger a NULL pointer dereference when a TCP connection
was closed asynchronously via iscsi_target_sk_state_change(), but only
when the initial PDU processing in iscsi_target_do_login() from iscsi_np
process context was blocked waiting for backend I/O to complete.

To address this issue, this patch makes the following changes.

First, it introduces some common helper functions used for checking
socket closing state, checking login_flags, and atomically checking
socket closing state + setting login_flags.

Second, it introduces a LOGIN_FLAGS_INITIAL_PDU bit to know when a TCP
connection has dropped via iscsi_target_sk_state_change(), but the
initial PDU processing within iscsi_target_do_login() in iscsi_np
context is still running.  For this case, it sets LOGIN_FLAGS_CLOSED,
but doesn't invoke schedule_delayed_work().

The original NULL pointer dereference case reported by MNC is now handled
by iscsi_target_do_login() doing a iscsi_target_sk_check_close() before
transitioning to FFP to determine when the socket has already closed,
or iscsi_target_start_negotiation() if the login needs to exchange
more PDUs (eg: iscsi_target_do_login returned 0) but the socket has
closed.  For both of these cases, the cleanup up of remaining connection
resources will occur in iscsi_target_start_negotiation() from iscsi_np
process context once the failure is detected.

Finally, to handle to case where iscsi_target_sk_state_change() is
called after the initial PDU procesing is complete, it now invokes
conn->login_work -> iscsi_target_do_login_rx() to perform cleanup once
existing iscsi_target_sk_check_close() checks detect connection failure.
For this case, the cleanup of remaining connection resources will occur
in iscsi_target_do_login_rx() from delayed workqueue process context
once the failure is detected.

Reported-by: Mike Christie 
Reviewed-by: Mike Christie 
Tested-by: Mike Christie 
Cc: Mike Christie 
Reported-by: Hannes Reinecke 
Cc: Hannes Reinecke 
Cc: Sagi Grimberg 
Cc: Varun Prakash 
Cc:  # v3.12+
Signed-off-by: Nicholas Bellinger

target/iscsi: split iscsit_check_dataout_hdr()

2017-02-19T05:24:15+00:00

Split iscsit_check_dataout_hdr() into two functions
1. __iscsit_check_dataout_hdr() - This function
   validates data out hdr.
2. iscsit_check_dataout_hdr() - This function finds
   iSCSI cmd using iscsit_find_cmd_from_itt_or_dump(),
   then it calls __iscsit_check_dataout_hdr() to
   validate iSCSI hdr.

This split is required to support Chelsio T6 iSCSI
DDP completion feature. T6 adapters reduce number of
completions to host by generating single completion
for all directly placed(DDP) iSCSI pdus in a sequence,
DDP completion contains iSCSI hdr of the last pdu in a
sequence.

On receiving DDP completion cxgbit driver will first
find iSCSI cmd using iscsit_find_cmd_from_itt_or_dump()
then updates cmd->write_data_done, cmd->next_burst_len,
cmd->data_sn and calls  __iscsit_check_dataout_hdr()
to validate iSCSI hdr.

(Move XRDSL check ahead of itt lookup / dump - nab)

Signed-off-by: Varun Prakash 
Signed-off-by: Bart Van Assche 
Signed-off-by: Nicholas Bellinger

target: Minimize #include directives

2016-12-09T18:22:28+00:00

Remove superfluous #include directives from the include/target/*.h
files. Add missing #include directives to other *.h and *.c files.
Use forward declarations for structures where possible. This
change reduces the build time for make M=drivers/target on my
laptop from 27.1s to 18.7s or by about 30%.

Signed-off-by: Bart Van Assche 
Cc: Christoph Hellwig 
Cc: Bryant G. Ly

cxgbit: Use type ISCSI_CXGBIT + cxgbit tpg_np attribute

2016-05-17T05:23:59+00:00

Instead of having cxgbit use type ISCSI_HW_OFFLOAD + 'hw_offload'
tpg_np attribute, it should be using it's own driver specific
type + attribute

Cc: Varun Prakash 
Cc: Hariprasad Shenai 
Cc: Christoph Hellwig 
Cc: Sagi Grimberg 
Signed-off-by: Nicholas Bellinger

iscsi-target: Convert transport drivers to signal rdma_shutdown

2016-05-17T05:23:33+00:00

Instead of special casing the handful of callers that check for
iser-target rdma verbs specific shutdown, use a simple flag at
iscsit_transport->rdma_shutdown so each driver can signal this.

Also, update iscsi-target/tcp + cxgbit to rdma_shutdown = false.

Cc: Varun Prakash 
Cc: Hariprasad Shenai 
Cc: Christoph Hellwig 
Cc: Sagi Grimberg 
Signed-off-by: Nicholas Bellinger

iscsi-target: export symbols

2016-05-10T06:12:28+00:00

export symbols for ISCSI_HW_OFFLOAD
transport drivers.

Signed-off-by: Varun Prakash 
Signed-off-by: Nicholas Bellinger

iscsi-target: add new offload transport type

2016-05-10T06:12:18+00:00

Add new transport type ISCSI_HW_OFFLOAD,
hw offload transport drivers will use
this transport type.

Signed-off-by: Varun Prakash 
Signed-off-by: Nicholas Bellinger

iscsi-target: move iscsit_thread_check_cpumask()

2016-05-10T06:12:09+00:00

Move iscsit_thread_check_cpumask() to header
file so that ISCSI_HW_OFFLOAD and other transport drivers
can call this function to ensure both tx and rx thread
runs on same cpu.

Signed-off-by: Varun Prakash 
Signed-off-by: Nicholas Bellinger

iscsi-target: add void (*iscsit_get_r2t_ttt)()

2016-05-10T06:12:08+00:00

Add void (*iscsit_get_r2t_ttt)() to
struct iscsit_transport, iscsi-target
uses this callback to get
r2t->targ_xfer_tag.

cxgbit.ko needs this callback
for Direct Data Placement of Data Out
pdus, adapter uses ttt in Data Out pdus
for placing data directly in to the host
buffers.

Signed-off-by: Varun Prakash 
Signed-off-by: Nicholas Bellinger

iscsi-target: add int (*iscsit_validate_params)()

2016-05-10T06:12:08+00:00

Add int (*iscsit_validate_params)() to
struct iscsit_transport, iscsi-target
uses this callback for validating
conn operational parameters.

cxgbit.ko needs this callback to check
and update the value of
MAXXMITDATASEGMENTLENGTH.

Signed-off-by: Varun Prakash 
Signed-off-by: Nicholas Bellinger