The address of the iovec &vq->iov[out] is not guaranteed to contain the scsi
command's response iovec throughout the lifetime of the command.  Rather, it
is more likely to contain an iovec from an immediately following command
after looping back around to vhost_get_vq_desc().  Pass along the iovec
entirely instead.

Fixes: 79c14141a487 ("vhost/scsi: Convert completion path to use copy_to_iter")
Cc: stable@vger.kernel.org
Signed-off-by: Benjamin Coddington <bcodding@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

Turns out the template and thus many drivers got the return value wrong:
0 means the fabrics driver needs to put a session reference, which no
driver except for the iSCSI target drivers did.  Fortunately none of these
drivers supports explicit Node ACLs, so the bug was harmless.

Even without that only qla2xxx and iscsi every did real work in
shutdown_session, so get rid of the boilerplate code in all other
drivers.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

Pull SCSI target updates from Nicholas Bellinger:
 "The highlights this round include:

   - Add target_alloc_session() w/ callback helper for doing se_session
     allocation + tag + se_node_acl lookup.  (HCH + nab)

   - Tree-wide fabric driver conversion to use target_alloc_session()

   - Convert sbp-target to use percpu_ida tag pre-allocation, and
     TARGET_SCF_ACK_KREF I/O krefs (Chris Boot + nab)

   - Convert usb-gadget to use percpu_ida tag pre-allocation, and
     TARGET_SCF_ACK_KREF I/O krefs (Andrzej Pietrasiewicz + nab)

   - Convert xen-scsiback to use percpu_ida tag pre-allocation, and
     TARGET_SCF_ACK_KREF I/O krefs (Juergen Gross + nab)

   - Convert tcm_fc to use TARGET_SCF_ACK_KREF I/O + TMR krefs

   - Convert ib_srpt to use percpu_ida tag pre-allocation

   - Add DebugFS node for qla2xxx target sess list (Quinn)

   - Rework iser-target connection termination (Jenny + Sagi)

   - Convert iser-target to new CQ API (HCH)

   - Add pass-through WRITE_SAME support for IBLOCK (Mike Christie)

   - Introduce data_bitmap for asynchronous access of data area (Sheng
     Yang + Andy)

   - Fix target_release_cmd_kref shutdown comp leak (Himanshu Madhani)

  Also, there is a separate PULL request coming for cxgb4 NIC driver
  prerequisites for supporting hw iscsi segmentation offload (ISO), that
  will be the base for a number of v4.7 developments involving
  iscsi-target hw offloads"

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (36 commits)
  target: Fix target_release_cmd_kref shutdown comp leak
  target: Avoid DataIN transfers for non-GOOD SAM status
  target/user: Report capability of handling out-of-order completions to userspace
  target/user: Fix size_t format-spec build warning
  target/user: Don't free expired command when time out
  target/user: Introduce data_bitmap, replace data_length/data_head/data_tail
  target/user: Free data ring in unified function
  target/user: Use iovec[] to describe continuous area
  target: Remove enum transport_lunflags_table
  target/iblock: pass WRITE_SAME to device if possible
  iser-target: Kill the ->isert_cmd back pointer in struct iser_tx_desc
  iser-target: Kill struct isert_rdma_wr
  iser-target: Convert to new CQ API
  iser-target: Split and properly type the login buffer
  iser-target: Remove ISER_RECV_DATA_SEG_LEN
  iser-target: Remove impossible condition from isert_wait_conn
  iser-target: Remove redundant wait in release_conn
  iser-target: Rework connection termination
  iser-target: Separate flows for np listeners and connections cma events
  iser-target: Add new state ISER_CONN_BOUND to isert_conn
  ...

This patch converts vhost/scsi pre-allocation of vhost_scsi_cmd
descriptors to use the new alloc_session callback().

Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

Looking at how callers use this, maybe we should just rename init_used
to vhost_vq_init_access. The _used suffix was a hint that we
access the vq used ring. But maybe what callers care about is
that it must be called after access_ok.

Also, this function manipulates the vq->is_le field which isn't related
to the vq used ring.

This patch simply renames vhost_init_used() to vhost_vq_init_access() as
suggested by Michael.

No behaviour change.

Signed-off-by: Greg Kurz <gkurz@linux.vnet.ibm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

Pull SCSI target updates from Nicholas Bellinger:
 "This series contains HCH's changes to absorb configfs attribute
  ->show() + ->store() function pointer usage from it's original
  tree-wide consumers, into common configfs code.

  It includes usb-gadget, target w/ drivers, netconsole and ocfs2
  changes to realize the improved simplicity, that now renders the
  original include/target/configfs_macros.h CPP magic for fabric drivers
  and others, unnecessary and obsolete.

  And with common code in place, new configfs attributes can be added
  easier than ever before.

  Note, there are further improvements in-flight from other folks for
  v4.5 code in configfs land, plus number of target fixes for post -rc1
  code"

In the meantime, a new user of the now-removed old configfs API came in
through the char/misc tree in commit 7bd1d4093c2f ("stm class: Introduce
an abstraction for System Trace Module devices").

This merge resolution comes from Alexander Shishkin, who updated his stm
class tracing abstraction to account for the removal of the old
show_attribute and store_attribute methods in commit 517982229f78
("configfs: remove old API") from this pull.  As Alexander says about
that patch:

 "There's no need to keep an extra wrapper structure per item and the
  awkward show_attribute/store_attribute item ops are no longer needed.

  This patch converts policy code to the new api, all the while making
  the code quite a bit smaller and easier on the eyes.

  Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>"

That patch was folded into the merge so that the tree should be fully
bisectable.

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (23 commits)
  configfs: remove old API
  ocfs2/cluster: use per-attribute show and store methods
  ocfs2/cluster: move locking into attribute store methods
  netconsole: use per-attribute show and store methods
  target: use per-attribute show and store methods
  spear13xx_pcie_gadget: use per-attribute show and store methods
  dlm: use per-attribute show and store methods
  usb-gadget/f_serial: use per-attribute show and store methods
  usb-gadget/f_phonet: use per-attribute show and store methods
  usb-gadget/f_obex: use per-attribute show and store methods
  usb-gadget/f_uac2: use per-attribute show and store methods
  usb-gadget/f_uac1: use per-attribute show and store methods
  usb-gadget/f_mass_storage: use per-attribute show and store methods
  usb-gadget/f_sourcesink: use per-attribute show and store methods
  usb-gadget/f_printer: use per-attribute show and store methods
  usb-gadget/f_midi: use per-attribute show and store methods
  usb-gadget/f_loopback: use per-attribute show and store methods
  usb-gadget/ether: use per-attribute show and store methods
  usb-gadget/f_acm: use per-attribute show and store methods
  usb-gadget/f_hid: use per-attribute show and store methods
  ...

This also allows to remove the target-specific old configfs macros, and
gets rid of the target_core_fabric_configfs.h header which only had one
function declaration left that could be moved to a better place.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Nicholas Bellinger <nab@linux-iscsi.org>
Acked-by: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

Pull virtio fixes and cleanups from Michael Tsirkin:
 "This fixes the virtio-test tool, and improves the error handling for
  virtio-ccw"

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost:
  virtio/s390: handle failures of READ_VQ_CONF ccw
  tools/virtio: propagate V=X to kernel build
  vhost: move features to core
  tools/virtio: fix build after 4.2 changes

virtio 1 and any layout are core features, move them
there. This fixes vhost test.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>