This patch fixes an active I/O shutdown bug for fabric
drivers using target_wait_for_sess_cmds(), where se_cmd
descriptor shutdown would result in hung tasks waiting
indefinitely for se_cmd->cmd_wait_comp to complete().

To address this bug, drop the incorrect list_del_init()
usage in target_wait_for_sess_cmds() and always complete()
during se_cmd target_release_cmd_kref() put, in order to
let caller invoke the final fabric release callback
into se_cmd->se_tfo->release_cmd() code.
Reported-by: Himanshu Madhani <himanshu.madhani@qlogic.com>
Tested-by: Himanshu Madhani <himanshu.madhani@qlogic.com>
Signed-off-by: Himanshu Madhani <himanshu.madhani@qlogic.com>
Cc: stable@vger.kernel.org
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

This patch modifies existing transport_complete_*() code
to avoid invoking target_core_fabric_ops->queue_data_in()
driver callbacks for I/O READs with non-GOOD SAM status.

Some initiators expect GOOD status when a DATA-IN payload
transfer is involved, so to be safe go ahead and always
invoke target_core_fabric_ops->queue_status() to generate
fabric responses instead.

Note this is a prerequisite for IBLOCK supporting retriable
status, so SAM_STAT_BUSY + SAM_STAT_TASK_SET_FULL always
generates fabric driver responses instead of initiating
DataIN payload transfer when non-GOOD status is present
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Sagi Grimberg <sagig@mellanox.com>
Cc: Andy Grover <agrover@redhat.com>
Cc: Mike Christie <mchristi@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

TCMU_MAILBOX_FLAG_CAP_OOOC was introduced, and userspace can check the flag
for out-of-order completion capability support.

Also update the document on how to use the feature.
Signed-off-by: Sheng Yang <sheng@yasker.org>
Reviewed-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

Fix the following printk size_t warning as per 0-day build:

All warnings (new ones prefixed by >>):

   drivers/target/target_core_user.c: In function 'is_ring_space_avail':
>> drivers/target/target_core_user.c:385:12: warning: format '%lu'
>> expects argument of type 'long unsigned int', but argument 3 has type
>> 'size_t {aka unsigned int}' [-Wformat=]
      pr_debug("no data space: only %lu available, but ask for %lu\n",
               ^
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

Which would result in NPE after when userspace connected again.

Expired command would be freed either when handling command(by userspace),
or when device was tearing down
Reviewed-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Sheng Yang <sheng@yasker.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

The data_bitmap was introduced to support asynchornization accessing of
data area.

We divide mailbox data area into blocks, and use data_bitmap to track the
usage of data area. All the new command's data would start with a new block,
and may left unusable space after it end. But it's easy to track using
data_bitmap.

Now we can allocate data area for asynchronization accessing from userspace,
since we can track the allocation using data_bitmap. The userspace part would
be the same as Maxim's previous asynchronized implementation.
Signed-off-by: Sheng Yang <sheng@yasker.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

Prepare for data_bitmap in the next patch.
Reviewed-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Sheng Yang <sheng@yasker.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

We don't need use one iovec per scatter-gather list entry, since data
area are continuous.
Reviewed-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Sheng Yang <sheng@yasker.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

se_dev_entry.lun_flags and se_lun.lun_access are only used for keeping
track of read-write vs. read-only state. Since this is an either/or thing
we can represent it as bool, and remove the unneeded enum
transport_lunflags_table, which is left over from when there were more
flags.

Change code that uses this enum to just use true/false, and make it clear
through variable and param names that true means read-only, false means
read-write.
Signed-off-by: Andy Grover <agrover@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

This patch has iblock pass the WRITE_SAME command to
the device for offloading if possible. It is similar to what is
done for UNMAP/discards, except that we export a large max write same
value to the initiator, and then rely on the block layer to
break it up into multiple requests if it cannot fit into one.

v2.

- Drop file backend changes and move helper function to
iblock backend.
Signed-off-by: Mike Christie <mchristi@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

We only use the pointer when processing regular iSER commands, and it then
always points to the struct iser_cmd that contains the TX descriptor.

Remove it and rely on container_of to save a little space and avoid a
pointer that is updated multiple times per processed command.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

There is exactly one instance per struct isert_cmd, so merge the two to
simplify everyones life.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

Use the workqueue based CQ type similar to what isert was using previously,
and properly split up the completion handlers.

Note that this also takes special care to handle the magic login WRs
separately, and also renames the submission functions so that it's clear
that they are only to be used for the login buffers.

(Fix up isert_print_wc usage in isert_beacon_done - nab)
Signed-off-by: Christoph Hellwig <hch@lst.de>
[sagig: added iscsi conn reinstatement in non-flush
 error completions and added error completion type print]
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

The login receive buffer is used as a iser_rx_desc, so type it as such
in struct isert_conn and allocate the exactly right space for it.  The
TX buffer is moved to a separate variable and properly sized as well.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

This is the same as ISCSI_DEF_MAX_RECV_SEG_LEN (and must be the same given
the structure layouts), so just use that constant instead.  This also
allows removing ISER_RX_LOGIN_SIZE in favor of ISER_RX_PAYLOAD_SIZE.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

We can never get to isert_wait_conn in INIT state anymore, so
get rid of this condition.
Signed-off-by: Jenny Derzhavetz <jennyf@mellanox.com>
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

With current termination flow we call release_conn after completion.
Signed-off-by: Jenny Derzhavetz <jennyf@mellanox.com>
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

When we receive an event that triggers connection termination,
we have a a couple of things we may want to do:
1. In case we are already terminating, bailout early
2. In case we are connected but not bound, disconnect and schedule
   a connection cleanup silently (don't reinstate)
3. In case we are connected and bound, disconnect and reinstate the connection

This rework fixes a bug that was detected against a mis-behaved
initiator which rejected our rdma_cm accept, in this stage the
isert_conn is no bound and reinstate caused a bogus dereference.

What's great about this is that we don't need the
post_recv_buf_count anymore, so get rid of it.
Signed-off-by: Jenny Derzhavetz <jennyf@mellanox.com>
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Cc: stable@vger.kernel.org # v3.10+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

No need to restrict this check to specific events.
Signed-off-by: Jenny Derzhavetz <jennyf@mellanox.com>
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Cc: stable@vger.kernel.org # v3.10+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

We need an indication that isert_conn->iscsi_conn binding has
happened so we'll know not to invoke a connection reinstatement
on an unbound connection which will lead to a bogus isert_conn->conn
dereferece.
Signed-off-by: Jenny Derzhavetz <jennyf@mellanox.com>
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Cc: stable@vger.kernel.org # v3.10+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

Once connection request is accepted, one rx descriptor
is posted to receive login request. This descriptor has rx type,
but is outside the main pool of rx descriptors, and thus
was mistreated as tx type.
Signed-off-by: Jenny Derzhavetz <jennyf@mellanox.com>
Signed-off-by: Sagi Grimberg <sagig@mellanox.com>
Cc: stable@vger.kernel.org # v3.10+
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

 #cat  /sys/kernel/debug/qla2xxx/qla2xxx_31/tgt_sess
 qla2xxx_31
 Port ID   Port Name                Handle
 ff:fc:01  21:fd:00:05:33:c7:ec:16  0
 01:0e:00  21:00:00:24:ff:7b:8a:e4  1
 01:0f:00  21:00:00:24:ff:7b:8a:e5  2
 ....

(Drop ->check_initiator_node_acl() parameter usage - nab)
Signed-off-by: Quinn Tran <quinn.tran@qlogic.com>
Signed-off-by: Himanshu Madhani <himanshu.madhani@qlogic.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

This patch converts ib_srpt to use existing percpu_ida tag
pre-allocation for struct srpt_send_ioctx.

This allows ib_srpt to drop it's internal pre-allocation
mechanisms with the extra spin_lock_irqsave, and use
percpu_ida common code for doing this.

Cc: Vu Pham <vu@mellanox.com>
Cc: Sagi Grimberg <sagig@mellanox.com>
Cc: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

This patch converts tcm_fc to modern TARGET_SCF_ACK_KREF
usage for ft_queue_status(), and fixes ft_check_stop_free()
to return transport_generic_free_cmd() for ->cmd_kref.

It also converts TM request -> ft_send_tm() to use ACK_KREF,
and update ft_queue_tm_resp() to drop the outstanding kref
after queueing TM response into fabric code.

Cc: Vasu Dev <vasu.dev@linux.intel.com>
Cc: Mark Rustad <mark.d.rustad@intel.com>
Cc: Robert Love <robert.w.love@intel.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

This patch converts xen-scsiback to modern TARGET_SCF_ACK_KREF
usage for scsiback_cmd_done() callback path.

It also also converts TMR -> scsiback_device_action() to use
modern target_submit_tmr() code.
Acked-by: Juergen Gross <jgross@suse.com>
Tested-by: Juergen Gross <jgross@suse.com>
Cc: Hannes Reinecke <hare@suse.de>
Cc: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

This patch converts xen-scsiback to use percpu_ida tag
pre-allocation for struct vscsibk_pend descriptor, in
order to avoid fast-path struct vscsibk_pend memory
allocations.

Note by default this is currently hardcoded to 128.

(Add wrapper for handling pending_req tag failure - Juergen)
(Drop left-over se_cmd memset in scsiback_cmd_exec - Juergen)
Acked-by: Juergen Gross <jgross@suse.com>
Tested-by: Juergen Gross <jgross@suse.com>
Cc: Hannes Reinecke <hare@suse.de>
Cc: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

This patch drops struct usbg_cmd->kref internal kref-erence
usage, for proper TARGET_SCF_ACK_KREF conversion.
Tested-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

This patch converts usb-gadget target to use percpu_ida tag
pre-allocation for struct usbg_cmd descriptor, in order to
avoid fast-path struct usbg_cmd memory allocations.

Note by default this is currently hardcoded to 128.
Tested-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Felipe Balbi <felipe.balbi@linux.intel.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

This patch converts sbp-target to modern TARGET_SCF_ACK_KREF
usage for sbp_send_status() callback path, and drops the now
obsolete sbp_free_request() failure path calls.
Acked-by: Chris Boot <bootc@bootc.net>
Tested-by: Chris Boot <bootc@bootc.net>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

This patch converts sbp-target to use struct sbp_target_request
descriptor tag pre-allocation using percpu_ida.

(Fix sbp_mgt_get_req() IS_ERR failure checking - Dan Carpenter)
(Add missing sbp_target_request tag memset - Chris Boot)
Acked-by: Chris Boot <bootc@bootc.net>
Tested-by: Chris Boot <bootc@bootc.net>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

This patch converts ib_srpt internal assignments of
se_node_acl and transport_register_session() to use
the new alloc_session method.

Cc: Vu Pham <vu@mellanox.com>
Cc: Sagi Grimberg <sagig@mellanox.com>
Cc: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

This patch converts tcm_fc target mode addition of tf_sess->hash to
port_id hlist_head using the new alloc_session callback().

Cc: Vasu Dev <vasu.dev@linux.intel.com>
Cc: Mark Rustad <mark.d.rustad@intel.com>
Cc: Robert Love <robert.w.love@intel.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

This patch converts existing qla2xxx target mode assignment
of struct qla_tgt_sess related sid + loop_id values to use
a callback via the new target_alloc_session API caller.

Cc: Himanshu Madhani <himanshu.madhani@qlogic.com>
Cc: Quinn Tran <quinn.tran@qlogic.com>
Cc: Giridhar Malavali <giridhar.malavali@qlogic.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

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>

This patch converts existing loopback, usb-gadget, and
xen-scsiback demo-mode only fabric drivers to use the
new target_alloc_session API caller.

This includes adding a new alloc_session callback for
fabric driver internal nexus pointer assignments.

(Fixes for early for-next nexus breakage - Dan Carpenter)

Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Acked-by: Juergen Gross <jgross@suse.com>
Tested-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Tested-by: Chris Boot <bootc@bootc.net>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

Based on HCH's original patch, this adds a full version to
support percpu-ida tag pre-allocation and callback function
pointer into fabric driver code to complete session setup.
Reported-by: Christoph Hellwig <hch@lst.de>
Cc: Sagi Grimberg <sagig@mellanox.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

Pull x86 fixes from Ingo Molnar:
 "This is unusually large, partly due to the EFI fixes that prevent
  accidental deletion of EFI variables through efivarfs that may brick
  machines.  These fixes are somewhat involved to maintain compatibility
  with existing install methods and other usage modes, while trying to
  turn off the 'rm -rf' bricking vector.

  Other fixes are for large page ioremap()s and for non-temporal
  user-memcpy()s"

* 'x86-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/mm: Fix vmalloc_fault() to handle large pages properly
  hpet: Drop stale URLs
  x86/uaccess/64: Handle the caching of 4-byte nocache copies properly in __copy_user_nocache()
  x86/uaccess/64: Make the __copy_user_nocache() assembly code more readable
  lib/ucs2_string: Correct ucs2 -> utf8 conversion
  efi: Add pstore variables to the deletion whitelist
  efi: Make efivarfs entries immutable by default
  efi: Make our variable validation list include the guid
  efi: Do variable name validation tests in utf8
  efi: Use ucs2_as_utf8 in efivarfs instead of open coding a bad version
  lib/ucs2_string: Add ucs2 -> utf8 helper functions

Pull perf fixes from Ingo Molnar:
 "A handful of CPU hotplug related fixes"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/core: Plug potential memory leak in CPU_UP_PREPARE
  perf/core: Remove the bogus and dangerous CPU_DOWN_FAILED hotplug state
  perf/core: Remove bogus UP_CANCELED hotplug state
  perf/x86/amd/uncore: Plug reference leak

Pull powerpc fixes from Michael Ellerman:
 - Fix build error on 32-bit with checkpoint restart from Aneesh Kumar
 - Fix dedotify for binutils >= 2.26 from Andreas Schwab
 - Don't trace hcalls on offline CPUs from Denis Kirjanov
 - eeh: Fix stale cached primary bus from Gavin Shan
 - eeh: Fix stale PE primary bus from Gavin Shan
 - mm: Fix Multi hit ERAT cause by recent THP update from Aneesh Kumar K.V
 - ioda: Set "read" permission when "write" is set from Alexey Kardashevskiy

* tag 'powerpc-4.5-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux:
  powerpc/ioda: Set "read" permission when "write" is set
  powerpc/mm: Fix Multi hit ERAT cause by recent THP update
  powerpc/powernv: Fix stale PE primary bus
  powerpc/eeh: Fix stale cached primary bus
  powerpc/pseries: Don't trace hcalls on offline CPUs
  powerpc: Fix dedotify for binutils >= 2.26
  powerpc/book3s_32: Fix build error with checkpoint restart