Remove the execute_cmd method in struct se_subsystem_api, and always use the
one directly in struct se_cmd.  To make life simpler for SBC virtual backends
a struct spc_ops that is passed to sbc_parse_cmd is added.  For now it
only contains an execute_rw member, but more will follow with the subsequent
commits.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

Remove the dead SCF_SE_ALLOW_EOO and SCF_DELAYED_CMD_FROM_SAM_ATTR
from se_cmd_flags_table.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

It's got no callers...
Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

see https://bugzilla.redhat.com/show_bug.cgi?id=818855

Adds a parameter so read-only block devices may be registered as
LIO backstores.
Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

These modules, along with other fabrics, should be loaded as-needed by
the LIO userspace tools.
Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

Also remove the unused ref_task_lun field in struct se_tmr_req.

(nab: Add missing TASK_REASSIGN ref_lun vs. ref_cmd orig_fe_lun checks
      in iscsit_tmr_task_reassign)
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

Since "target: Drop se_device TCQ queue_depth usage from I/O path" we always
submit all commands (or back then, tasks) from __transport_execute_tasks.

That means the the execute list has lots its purpose, as we can simply
submit the commands that are restarted in transport_complete_task_attr
directly while we walk the list.  In fact doing so also solves a race
in the way it currently walks to delayed_cmd_list as well.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

This patch changes back the pSCSI backend to follow pre 3.6-queue code to
passthrough SPC-3 persistent reservations + SPC-2 legacy reservation
handling to the underlying LLD / physical hardware.

For folks who really need this for their own SPC-3 emulation logic, avoid
changing the functionality of this beyond what is exported for REPORT_LUNS
for existing code, and to avoid problems with SPC-3 PR/ALUA as INQUIRY
EVPD=0x83 emulation needs to be in place in order for this to work as
expected with spc_parse_cdb() code..

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

The MAINTENANCE_[IN,OUT] CDB parsing required for generic ALUA emulation
needs to be in spc_parse_cdb() to function for virtual TYPE_DISK exports,
instead of in backend pscsi_parse_cdb() code used only for passthrough ops.

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

The virtual drivers don't need to clear cdb fields they never look at, so move
this code into the pscsi backend.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

Move the existing code in target_core_cdb.c into the files for the command
sets that the emulations implement.

(roland + nab: Squash patch: Fix range calculation in WRITE SAME emulation
 when num blocks == 0s)
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

Instead of trying to handle all SCSI command sets in one function
(transport_generic_cmd_sequencer) call out to the backend driver to perform
this functionality.  For pSCSI a copy of the existing code is used, but for
all virtual backends we can use a new parse_sbc_cdb helper is used to
provide a simple SBC emulation.

For now this setups means a fair amount of duplication between pSCSI and the
SBC library, but patches later in this series will sort out that problem.

(nab: Fix up build failure in target_core_pscsi.c)
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

(nab: Add EXPORT_SYMBOL usage for spc_parse_cdb)
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

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

We don't need three flags to classifiy the CDB as we can check for a NULL S/G
list for a dataless command, and can infer from the absence of the data flag
that we deal with a control CDB.  Also remove the _SG_IO from the data CDB
flag as all I/O is dont on S/G lists now.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

Move all code not related to cdb parsing from transport_generic_cmd_sequencer
into target_setup_cmd_from_cdb.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

When NUMBER OF LOGICAL BLOCKS is 0, WRITE SAME is supposed to write
all the blocks from the specified LBA through the end of the device.
However, dev->transport->get_blocks(dev) (perhaps confusingly) returns
the last valid LBA rather than the number of blocks, so the correct
number of blocks to write starting with lba is

dev->transport->get_blocks(dev) - lba + 1

(nab: Backport roland's for-3.6 patch to for-3.5)
Signed-off-by: Roland Dreier <roland@purestorage.com>
Cc: Cc: <stable@vger.kernel.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

 - instead of (PTR_ERR(file) < 0) just use IS_ERR(file)
 - return -EINVAL instead of EINVAL
 - all other error returns in target_scsi3_emulate_pr_out() use
   "goto out" -- get rid of the one remaining straight "return."
Signed-off-by: Roland Dreier <roland@purestorage.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

This patch fixes a crash seen when large reads have their exchange
aborted by either timing out or being reset. Because the exchange
abort results in the seq pointer being set to NULL, because the
sequence is no longer valid, it must not be dereferenced. This
patch changes the function ft_get_task_tag to return ~0 if it is
unable to get the tag for this reason. Because the get_task_tag
interface provides no means of returning an error, this seems
like the best way to fix this issue at the moment.
Signed-off-by: Mark Rustad <mark.d.rustad@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

Based upon Alan's patch from Coverity scan id 793583, these debug
messages in qlt_async_event() should be starting from byte 0, which is
always the Asynchronous Event Status Code from the parent switch statement.

Also, rename reason_code -> login_code following the language used in
2500 FW spec for Port Database Changed (0x8014) -> Port Database Changed
Event Mailbox Register for mailbox[2].
Signed-off-by: Alan Cox <alan@linux.intel.com>
Cc: Chad Dupuis <chad.dupuis@qlogic.com>
Cc: Giridhar Malavali <giridhar.malavali@qlogic.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

Use rcu_dereference_protected to tell rcu that the ft_lport_lock
is held during ft_lport_create. This resolved "suspicious RCU usage"
warnings when debugging options are turned on.
Signed-off-by: Mark Rustad <mark.d.rustad@intel.com>
Tested-by: Ross Brattain <ross.b.brattain@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

version.h header file is no longer required for qla_target code.
Signed-off-by: Sachin Kamat <sachin.kamat@linaro.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

If we make a variable an unsigned int and then expect it to be < 0 on
a bad character, we're going to have a bad time.  Fix the tcm_qla2xxx
code to actually notice if hex_to_bin() returns a negative variable.

This was detected by the compiler warning:

    scsi/qla2xxx/tcm_qla2xxx.c: In function ‘tcm_qla2xxx_npiv_extract_wwn’:
    scsi/qla2xxx/tcm_qla2xxx.c:148:3: warning: comparison of unsigned expression >= 0 is always true [-Wtype-limits]
Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

If we go to the "out_term:" exit path in qlt_do_work(), we call
qlt_send_term_exchange() with a NULL cmd, which means that it can't
possibly free the cmd for us.  Add an explicit call to free the
command memory, so we don't leak the allocation.

This will also fix warnings about "BUG qla_tgt_cmd_cachep: Objects
remaining on kmem_cache_close" from slub when unloading the qla2xxx
target module.
Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

In qlt_do_ctio_completion(), there's no point in calling
qlt_term_ctio_exchange() with a NULL cmd -- all that it does is crash
in a NULL pointer dereference, since it does

	qlt_send_term_exchange(vha, cmd, &cmd->atio, 1);

and dereferencing &cmd->atio is a bad idea if cmd itself is NULL.

If we really need to do this, we could take the values from the
failed CTIO we're processing, but it's not clear if it's worth
the replumbing to do that.
Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

When we create an explicit node ACL in tcm_qla2xxx_make_nodeacl(),
there is a call to tcm_qla2xxx_setup_nacl_from_rport(), which puts the
node ACL into the lport_fcport_map even though there is no session yet
for the initiator.  Since the only time we remove entries from this
map is when we free a session, this means that if we later delete this
node ACL without the initiator ever creating a session, we'll leave
the nacl pointer in the btree pointing at freed memory.

This is especially bad if that initiator later does send us a command
that would cause us to create a dynamic ACL and session: we'll find
the stale freed nacl pointer in the btree and end up with use-after-free.

We could add more code to clear the btree entry when deleting the
explicit nacl, but the original insertion is pointless: without a
session attached, we'll just have to update the entry when a session
appears anyway.  So we can just delete tcm_qla2xxx_setup_nacl_from_rport()
and the code that calls it.
Signed-off-by: Roland Dreier <roland@purestorage.com>
Cc: Chad Dupuis <chad.dupuis@qlogic.com>
Cc: Giridhar Malavali <giridhar.malavali@qlogic.com>
Cc: Arun Easi <arun.easi@qlogic.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

The error paths in target_emulate_set_target_port_groups() are all
essentially "rc = -EINVAL; goto out;" but the code at "out:" ignores
rc and always returns success.  This means that even if eg explicit
ALUA is turned off, the initiator will always see a good SCSI status
for SET TARGET PORT GROUPS.

Fix this by returning rc as is intended.  It appears this bug was
added by the following patch:

commit 05d1c7c0
Author: Andy Grover <agrover@redhat.com>
Date:   Wed Jul 20 19:13:28 2011 +0000

    target: Make all control CDBs scatter-gather
Signed-off-by: Roland Dreier <roland@purestorage.com>
Cc: Andy Grover <agrover@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

This patch adds a new tcm_qla2xxx_clear_sess_lookup() call to clear session
specific s_id + loop_id entries used for se_node_acl pointer lookup ahead
of releasing se_session within the process context workqueue callback in
tcm_qla2xxx_free_session().

It makes the call in existing tcm_qla2xxx_clear_nacl_from_fcport_map()
code invoked from qlt_unreg_sess() in interrupt context w/ hardware_lock
held, ahead of the process context callback into qlt_free_session_done()
-> tcm_qla2xxx_free_session().

We are doing this to address a race between incoming ATIO or TMR packets
using stale se_node_acl pointer once session shutdown has been invoked via
qlt_unreg_sess() in qla_target.c LLD code, and when the entire tcm_qla2xxx
endpoint has not been forced into shutdown w/ echo 0 > ../$QLA2XXX_PORT/enable

Cc: Joern Engel <joern@logfs.org>
Cc: Roland Dreier <roland@purestorage.com>
Cc: Arun Easi <arun.easi@qlogic.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

This patch converts tcm_qla2xxx code to use an internal kref_put() for
se_session->sess_kref in order to ensure that qla_hw_data->hardware_lock
can be held while calling qlt_unreg_sess() for the final put.
Signed-off-by: Joern Engel <joern@logfs.org>
Cc: Roland Dreier <roland@purestorage.com>
Cc: Arun Easi <arun.easi@qlogic.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

This patch adds an optional target_core_fabric_ops->put_session() caller
within the existing target_put_session() code path.

This is required by tcm_qla2xxx code in order to invoke it's own fabric
specific session shutdown handler using se_session->sess_kref.
Signed-off-by: Joern Engel <joern@logfs.org>
Cc: Roland Dreier <roland@purestorage.com>
Cc: Arun Easi <arun.easi@qlogic.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

If the privileges given to root threads (3% of allowable memory) or a
negative value of /proc/pid/oom_score_adj happen to exceed the amount of
rss of a thread, its badness score overflows as a result of commit
a7f638f9 ("mm, oom: normalize oom scores to oom_score_adj scale only
for userspace").

Fix this by making the type signed and return 1, meaning the thread is
still eligible for kill, if the value is negative.
Reported-by: Dave Jones <davej@redhat.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: David Rientjes <rientjes@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull scheduler fixes from Ingo Molnar.

* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched: Fix the relax_domain_level boot parameter
  sched: Validate assumptions in sched_init_numa()
  sched: Always initialize cpu-power
  sched: Fix domain iteration
  sched/rt: Fix lockdep annotation within find_lock_lowest_rq()
  sched/numa: Load balance between remote nodes
  sched/x86: Calculate booted cores after construction of sibling_mask

Fix lots of new kernel-doc warnings in kernel/sched/fair.c:

  Warning(kernel/sched/fair.c:3625): No description found for parameter 'env'
  Warning(kernel/sched/fair.c:3625): Excess function parameter 'sd' description in 'update_sg_lb_stats'
  Warning(kernel/sched/fair.c:3735): No description found for parameter 'env'
  Warning(kernel/sched/fair.c:3735): Excess function parameter 'sd' description in 'update_sd_pick_busiest'
  Warning(kernel/sched/fair.c:3735): Excess function parameter 'this_cpu' description in 'update_sd_pick_busiest'
  .. more warnings
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This reverts commit 9e612a00.

It incorrectly finds VGA connectors where none are attached, apparently
not noticing that nothing replied to the EDID queries, and happily using
the default EDID modes that have nothing to do with actual hardware.

That in turn then causes X to fall down to the lowest common
denominator, which is usually the default 1024x768 mode that is in the
default EDID and pretty much anything supports).

I'd suggest that if not relying on the HDP pin, the code should at least
check whether it gets valid EDID data back, rather than just assume
there's something on the VGA connector.

Cc: Dave Airlie <airlied@linux.ie>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Pull ext4 bug fixes from Theodore Ts'o:
 "This update contains two bug fixes, both destined for the stable tree.
  Perhaps the most important is one which fixes ext4 when used with file
  systems originally formatted for use with ext3, but then later
  converted to take advantage of ext4."

* tag 'ext4_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: don't set i_flags in EXT4_IOC_SETFLAGS
  ext4: fix the free blocks calculation for ext3 file systems w/ uninit_bg

Pull powerpc fixes from Paul Mackerras:
 "Two small fixes for powerpc:
   - a fix for a regression since 3.2 that causes 4-second (or longer)
     pauses
   - a fix for a potential oops when loading kernel modules on 32-bit
     embedded systems."

* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc:
  powerpc: Fix kernel panic during kernel module load
  powerpc/time: Sanity check of decrementer expiration is necessary

Pull UBI/UBIFS fixes from Artem Bityutskiy:
 "Fix UBI and UBIFS - they refuse to work without debugfs.  This was
  broken by the 3.5-rc1 UBI/UBIFS changes when we removed the debugging
  Kconfig switches.

  Also, correct locking in 'ubi_wl_flush()' - it was extended to support
  flushing a specific LEB in 3.5-rc1, and the locking was sub-optimal."

* tag 'upstream-3.5-rc2' of git://git.infradead.org/linux-ubifs:
  UBI: correct ubi_wl_flush locking
  UBIFS: fix debugfs-less systems support
  UBI: fix debugfs-less systems support

This reverts commit 7732a557 (and commit
3f50fff4, which was a follow-up
cleanup).

We're chasing an elusive bug that Dave Jones can apparently reproduce
using his system call fuzzer tool, and that looks like some kind of
locking ordering problem on the directory i_mutex chain.  Our i_mutex
locking is rather complex, and depends on the topological ordering of
the directories, which is why we have been very wary of splicing
directory entries around.

Of course, we really don't want to ever see aliased unconnected
directories anyway, so none of this should ever happen, but this revert
aims to basically get us back to a known older state.

Bruce points to some of the previous discussion at

       http://marc.info/?i=<20110310105821.GE22723@ZenIV.linux.org.uk>

and in particular a long post from Neil:

       http://marc.info/?i=<20110311150749.2fa2be66@notabene.brown>

It should be noted that it's possible that Dave's problems come from
other changes altohgether, including possibly just the fact that Dave
constantly is teachning his fuzzer new tricks.  So what appears to be a
new bug could in fact be an old one that just gets newly triggered, but
reverting these patches as "still under heavy discussion" is the right
thing regardless.
Requested-by: Al Viro <viro@zeniv.linux.org.uk>
Acked-by: J. Bruce Fields <bfields@fieldses.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>