Pull SCSI update from James Bottomley:
 "This is a much shorter set of patches that were on the go but didn't
  make it in to the early pull request for the merge window.  It's
  really a set of bug fixes plus some final cleanup work on the new tag
  queue API"

* tag 'scsi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  storvsc: ring buffer failures may result in I/O freeze
  ipr: set scsi_level correctly for disk arrays
  ipr: add support for async scanning to speed up boot
  scsi_debug: fix missing "break;" in SDEBUG_UA_CAPACITY_CHANGED case
  scsi_debug: take sdebug_host_list_lock when changing capacity
  scsi_debug: improve driver description in Kconfig
  scsi_debug: fix compare and write errors
  qla2xxx: fix race in handling rport deletion during recovery causes panic
  scsi: blacklist RSOC for Microsoft iSCSI target devices
  scsi: fix random memory corruption with scsi-mq + T10 PI
  Revert "[SCSI] mpt3sas: Remove phys on topology change"
  Revert "[SCSI] mpt2sas: Remove phys on topology change."
  esas2r: Correct typos of "validate" in a comment
  fc: FCP_PTA_SIMPLE is 0
  ibmvfc: remove unused tag variable
  scsi: remove MSG_*_TAG defines
  scsi: remove scsi_set_tag_type
  scsi: remove scsi_get_tag_type
  scsi: never drop to untagged mode during queue ramp down
  scsi: remove ->change_queue_type method

Pull SCSI target fixes from Nicholas Bellinger:
 "The highlights this merge window include:

   - Allow target fabric drivers to function as built-in.  (Roland)
   - Fix tcm_loop multi-TPG endpoint nexus bug.  (Hannes)
   - Move per device config_item_type into se_subsystem_api, allowing
     configfs attributes to be defined at module_init time.  (Jerome +
     nab)
   - Convert existing IBLOCK/FILEIO/RAMDISK/PSCSI/TCMU drivers to use
     external configfs attributes.  (nab)
   - A number of iser-target fixes related to active session + network
     portal shutdown stability during extended stress testing.  (Sagi +
     Slava)
   - Dynamic allocation of T10-PI contexts for iser-target, fixing a
     potentially bogus iscsi_np->tpg_np pointer reference in >= v3.14
     code.  (Sagi)
   - iser-target performance + scalability improvements.  (Sagi)
   - Fixes for SPC-4 Persistent Reservation AllRegistrants spec
     compliance.  (Ilias + James + nab)
   - Avoid potential short kern_sendmsg() in iscsi-target for now until
     Al's conversion to use msghdr iteration is merged post -rc1.
     (Viro)

  Also, Sagi has requested a number of iser-target patches (9) that
  address stability issues he's encountered during extended stress
  testing be considered for v3.10.y + v3.14.y code.  Given the amount of
  LOC involved, it will certainly require extra backporting effort.

  Apologies in advance to Greg-KH & Co on this.  Sagi and I will be
  working post-merge to ensure they each get applied correctly"

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (53 commits)
  target: Allow AllRegistrants to re-RESERVE existing reservation
  uapi/linux/target_core_user.h: fix headers_install.sh badness
  iscsi-target: Fail connection on short sendmsg writes
  iscsi-target: nullify session in failed login sequence
  target: Avoid dropping AllRegistrants reservation during unregister
  target: Fix R_HOLDER bit usage for AllRegistrants
  iscsi-target: Drop left-over bogus iscsi_np->tpg_np
  iser-target: Fix wc->wr_id cast warning
  iser-target: Remove code duplication
  iser-target: Adjust log levels and prettify some prints
  iser-target: Use debug_level parameter to control logging level
  iser-target: Fix logout sequence
  iser-target: Don't wait for session commands from completion context
  iser-target: Reduce CQ lock contention by batch polling
  iser-target: Introduce isert_poll_budget
  iser-target: Remove an atomic operation from the IO path
  iser-target: Remove redundant call to isert_conn_terminate
  iser-target: Use single CQ for TX and RX
  iser-target: Centralize completion elements to a context
  iser-target: Cast wr_id with uintptr_t instead of unsinged long
  ...

This patch changes core_scsi3_pro_release() logic to allow an
existing AllRegistrants type reservation to be re-reserved by
any registered I_T nexus.

This addresses a issue where AllRegistrants type RESERVE was
receiving RESERVATION_CONFLICT status if dev_pr_res_holder did
not match the same I_T nexus, instead of just returning GOOD
status following spc4r34 Section 5.9.9:

"If the device server receives a PERSISTENT RESERVE OUT command
 with RESERVE service action where the TYPE field and the SCOPE
 field contain the same values as the existing type and scope
 from a persistent reservation holder, it shall not make any
 change to the existing persistent reservation and shall complete
 the command with GOOD status."

Reported-by: Ilias Tsitsimpis <i.tsitsimpis@gmail.com>
Cc: Ilias Tsitsimpis <i.tsitsimpis@gmail.com>
Cc: Lee Duncan <lduncan@suse.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

This patch changes iscsit_do_tx_data() to fail on short writes
when kernel_sendmsg() returns a value different than requested
transfer length, returning -EPIPE and thus causing a connection
reset to occur.

This avoids a potential bug in the original code where a short
write would result in kernel_sendmsg() being called again with
the original iovec base + length.

In practice this has not been an issue because iscsit_do_tx_data()
is only used for transferring 48 byte headers + 4 byte digests,
along with seldom used control payloads from NOPIN + TEXT_RSP +
REJECT with less than 32k of data.

So following Al's audit of iovec consumers, go ahead and fail
the connection on short writes for now, and remove the bogus
logic ahead of his proper upstream fix.

Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Cc: David S. Miller <davem@davemloft.net>
Cc: <stable@vger.kernel.org> # v3.1+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

In case login sequence failed, make sure conn->sess is
NULL before calling wait_conn as some transports (iser)
may rely on that (waiting for session commands).

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

This patch fixes an issue with AllRegistrants reservations where
an unregister operation by the I_T nexus reservation holder would
incorrectly drop the reservation, instead of waiting until the
last active I_T nexus is unregistered as per SPC-4.

This includes updating __core_scsi3_complete_pro_release() to reset
dev->dev_pr_res_holder with another pr_reg for this special case,
as well as a new 'unreg' parameter to determine when the release
is occuring from an implicit unregister, vs. explicit RELEASE.

It also adds special handling in core_scsi3_free_pr_reg_from_nacl()
to release the left-over pr_res_holder, now that pr_reg is deleted
from pr_reg_list within __core_scsi3_complete_pro_release().

Reported-by: Ilias Tsitsimpis <i.tsitsimpis@gmail.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

This patch fixes the usage of R_HOLDER bit for an All Registrants
reservation in READ_FULL_STATUS, where only the registration who
issued RESERVE was being reported as having an active reservation.

It changes core_scsi3_pri_read_full_status() to check ahead of the
list walk of active registrations to see if All Registrants is active,
and if so set R_HOLDER bit and scope/type fields for all active
registrations.

Reported-by: Ilias Tsitsimpis <i.tsitsimpis@gmail.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

This patch drops the left-over iscsi_np->tpg_np pointer, now
that iser-target PI is able to dynamically allocate PI contexts
per I/O, instead of needing to determine support using a TPG
attribute with this bogus reference.

Cc: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

iSER will report supported protection operations based on
the tpg attribute t10_pi settings and HCA PI offload capabilities.
If the HCA does not support PI offload or tpg attribute t10_pi is
not set, we fall to SW PI mode.

In order to do that, we move iscsit_get_sup_prot_ops after connection
tpg assignment.

Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Cc: <stable@vger.kernel.org> # v3.14+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>