Now that we don't split commands the lba field in the task is always
equivalent to the one in the CDB, even in cases where we have two tasks
due to a BIDI transfer.  Just refer the the lba in the command instead
of duplicating it in the task.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

Now that tasks are always the same size as the command there is no need
to rewrite a CDB in common code.  Notw that we keep the separately allocated
CDB in the pscsi and stgt backends for now, to easy reintroducing any
command splitting local to these backends if nessecary.
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>

The SCSI MMC GET_EVENT_STATUS_NOTIFICATION command can be used to find
out about media change, among other things.  This patch adds it to the
command sequencer so that PSCSI CD-ROM passthrough works with modern
Linux guests that issue this command.
Tested-by: Cong Meng <mengcong@cn.ibm.com>
Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

We can use kcalloc() here instead of kzalloc().  It's better style and
it has overflow checking built in.

Also -ENOMEM is the correct error code for allocation errors.  -1 means
-EPERM.  None of the callers preserve the error codes so it doesn't
matter except as a cleanup.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

We originally changed iscsi to allocate its own buffers just as an
intermediate step to clean up some core buffer allocation mechanisms. Now
we can put it back.

Also had to change allocate_iovecs to use data_length instead of
t_data_nents because iovecs are now allocated before the data buffer, thus
t_data_nents is not yet initialized.
Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

It appears iscsi is the only one to call this in its cmd submit path, but
it appears to be applicable to all fabrics, and should always be called.
Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

Rename iscsit_build_pdu_and_seq_list to iscsit_do_build_pdu_and_seq_lists

Rename iscsit_do_build_list to iscsit_build_pdu_and_seq_lists

Move code from iscsit_decide_list_to_build into _seq_pdu_list.c, seems
a better fit.

Also update some comments in pdu/seq code for correctness and whitespace.
Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

Redundant, just use iscsi_cmd->se_cmd.data_length once se_cmd is
initialized, or hdr->data_length before then.
Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

if we can get calls to init_se_cmd, get_sess_cmd, lookup_cmd_lun,
core_alua_check_nonop_delay, and handle_cdb_direct next to each other,
then we can just call target_submit_cmd. This is a step towards that
goal.
Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

Trying to move a bunch of stuff around so iscsi can use target_submit_cmd
someday, and so stuff needs to be in that function directly instead of
hidden, so it can be reordered etc.
Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

This patch renames a horribly misnamed function that no longer allocate
tasks to something more descriptive for it's modern use in target core.

(nab: Fix up ib_srpt to use this as well ahead of a target_submit_cmd
conversion)
Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

This patch includes the handful of squashed patches for target/iscsi from
Andy's original series into lio-core/master code:

*) Make iscsit_add_reject static
*) Remove unused data_offset_end from iscsi_datain_req
*) Remove "#if 0" stubs
*) Rename iscsi_datain_req to cmd_datain_node
*) Cleanups for built_r2ts_for_cmd()
*) Cleanups for Cleanup build_sendtargets_response()
Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

Immediate queue:

Consolidate down to one switch statement by moving send_tx_data and stuff
from second switch into the first switch, or the functions the first switch
calls.

Response queue:

Do not lock istate_lock except directly around i_state modifications.

Put entire ISTATE_SEND_DATAIN path within first switch statement, in prep
for further refactoring.

All other cases set use_misc = 1 and will not be using sendpage, so just
use send_tx_data for these and set use_misc param to 1.

map_sg, sent_status, use_misc, and se_cmd vars no longer needed.

Then put immediate and response handling in separate functions in order
to get iscsi_target_tx_thread down to where it fits on a page.
Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

When processing immediate queue, we're switching on a local variable
so it's not necessary to lock around it. However, we are modifying
cmd->i_state in two spots, so lock around those parts only.
Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

*) Use decoded cmd->immediate_cmd for conditional instead of
   re-examining hdr->opcode
*) Make iscist_dataout_post_crc_passed more legible
*) use max() to reduce code in build_r2ts_for_cmd()
*) Remove CONFIG_SMP and if 0 ifdefs
*) Replace if/goto with a while loop
*) Remove unused conn->tx_immediate_queue and tx_response_queue
Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

The name change makes it clear this list_head is so the cmd can be an
item in the connection's conn_cmd_list.
Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

Now that all fabrics are converted over to using se_cmd->t_data_sg
directly, we can drop the task sg chaining support.  With the modern
memory allocation in target core, task sg chaining is needless
overhead -- we would split up the main cmd sglist into pieces, and
then splice those pieces back together instead of just using the
original list directly.
Signed-off-by: Roland Dreier <roland@purestorage.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

With the modern target core, se_cmd->t_data_sg already points to a
sglist that covers the whole command.  So task_sg chaining is needless
overhead and obfuscation -- instead of splicing the split up task
sglists back into one list, we can just use the original list directly.
Signed-off-by: Roland Dreier <roland@purestorage.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

With the modern target core, se_cmd->t_data_sg already points to a
sglist that covers the whole command.  So task_sg chaining is needless
overhead and obfuscation -- instead of splicing the split up task
sglists back into one list, we can just use the original list directly.
Signed-off-by: Roland Dreier <roland@purestorage.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Kiran Patil <Kiran.patil@intel.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

From hch:

The high-performance backends (iblock and rd) support tasks of unlimited
size.  With that there is no reason to keep a complex infrastructure for
splitting up commands in place.  Stop doing so and only submit a single
task per data direction.  Once this is in place we can slowly remove fields
from the task that duplicate things in the command, or move other fields
into the command.

From nab:

The benefit to IBLOCK performance by removing the additional
fast-path allocation overhead + SGL mapping to se_task->task_sg[] is now
greater than transparently supporting an received CDB I/O length that
exceeds what is allowed by backend pSCSI LLD hardware max_sectors, that
was originally supported for all backend export cases.

This change may effect some users of pSCSI users on legacy hardware, but
I think most folks are now using TYPE_DISK struct scsi_device export
with IBLOCK.  The only other place where this may can issues that cannot
be resolved with IBLOCK TYPE_DISK is using TYPE_ROM, TYPE_TAPE or other
pSCSI non TYPE_DISK export with an SCSI LLDs using a smaller
max_sectors.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

The ramdisk backend has not inherent limitations for handling requests,
so don't artificially limits the transfer size.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

Remove various leftovers of the old direct/indirect split, as well as the
unused rd_request structure and a couple unused defines and fields.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

The UASP protocol does not inform the target device upfront how much
data it should expect so we have to learn in from the CDB.  So in order
to handle this case, add a TARGET_SCF_UNKNOWN_SIZE to target_submit_cmd()
and perform an explictly assignment for se_cmd->data_length from the
extracted CDB size in transport_generic_cmd_sequencer().
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

This was used at one time as a hack by FILEIO backend registration to
allow a struct block_device that was claimed with blkdev_get (by a local
filesystem mount for example) to be exported as read-only (SCSI WP=1).

Since FILEIO backend registration will no longer attempt to obtain
exclusive access to an underlying struct block_device here, this flag is
now obsolete.
Reported-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

Pull two more small regmap fixes from Mark Brown:
 - Now we have users for it that aren't running Android it turns out
   that regcache_sync_region() is much more useful to drivers if it's
   exported for use by modules.  Who knew?
 - Make sure we don't divide by zero when doing debugfs dumps of
   rbtrees, not visible up until now because everything was providing at
   least some cache on startup.

* tag 'regmap-3.4-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/regmap:
  regmap: prevent division by zero in rbtree_show
  regmap: Export regcache_sync_region()

Pull a few KVM fixes from Avi Kivity:
 "A bunch of powerpc KVM fixes, a guest and a host RCU fix (unrelated),
  and a small build fix."

* 'kvm-updates/3.4' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: Resolve RCU vs. async page fault problem
  KVM: VMX: vmx_set_cr0 expects kvm->srcu locked
  KVM: PMU: Fix integer constant is too large warning in kvm_pmu_set_msr()
  KVM: PPC: Book3S: PR: Fix preemption
  KVM: PPC: Save/Restore CR over vcpu_run
  KVM: PPC: Book3S HV: Save and restore CR in __kvmppc_vcore_entry
  KVM: PPC: Book3S HV: Fix kvm_alloc_linear in case where no linears exist
  KVM: PPC: Book3S: Compile fix for ppc32 in HIOR access code

Pull SuperH fixes from Paul Mundt.

* tag 'sh-for-linus' of git://github.com/pmundt/linux-sh:
  sh: fix clock-sh7757 for the latest sh_mobile_sdhi driver
  serial: sh-sci: use serial_port_in/out vs sci_in/out.
  sh: vsyscall: Fix up .eh_frame generation.
  sh: dma: Fix up device attribute mismatch from sysdev fallout.
  sh: dwarf unwinder depends on SHcompact.
  sh: fix up fallout from system.h disintegration.

Pull security layer fixlet from James Morris.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security:
  sysctl: fix write access to dmesg_restrict/kptr_restrict

Pull ACPI & Power Management patches from Len Brown:
 "Two fixes for cpuidle merge-window changes, plus a URL fix in
  MAINTAINERS"

* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux:
  MAINTAINERS: Update git url for ACPI
  cpuidle: Fix panic in CPU off-lining with no idle driver
  ACPI processor: Use safe_halt() rather than halt() in acpi_idle_play_dead()

Pull target fixes from Nicholas Bellinger:
 "Pull two tcm_fc fabric related fixes for -rc2:

  Note that both have been CC'ed to stable, and patch #1 is the
  important one that addresses a memory corruption bug related to FC
  exchange timeouts + command abort.

  Thanks again to MDR for tracking down this issue!"

* '3.4-rc-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending:
  tcm_fc: Do not free tpg structure during wq allocation failure
  tcm_fc: Add abort flag for gracefully handling exchange timeout

Avoid freeing a registered tpg structure if an alloc_workqueue call
fails.  This fixes a bug where the failure was leaking memory associated
with se_portal_group setup during the original core_tpg_register() call.
Signed-off-by: Mark Rustad <mark.d.rustad@intel.com>
Acked-by: Kiran Patil <Kiran.patil@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

Add abort flag and use it to terminate processing when an exchange
is timed out or is reset. The abort flag is used in place of the
transport_generic_free_cmd function call in the reset and timeout
cases, because calling that function in that context would free
memory that was in use. The aborted flag allows the lifetime to
be managed in a more normal way, while truncating the processing.

This change eliminates a source of memory corruption which
manifested in a variety of ugly ways.

(nab: Drop unused struct fc_exch *ep in ft_recv_seq)
Signed-off-by: Mark Rustad <mark.d.rustad@intel.com>
Acked-by: Kiran Patil <Kiran.patil@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

Signed-off-by: Igor Murzov <e-mail@date.by>
Signed-off-by: Len Brown <len.brown@intel.com>

Pull arch/tile bug fixes from Chris Metcalf:
 "This includes Paul Gortmaker's change to fix the <asm/system.h>
  disintegration issues on tile, a fix to unbreak the tilepro ethernet
  driver, and a backlog of bugfix-only changes from internal Tilera
  development over the last few months.

  They have all been to LKML and on linux-next for the last few days.
  The EDAC change to MAINTAINERS is an oddity but discussion on the
  linux-edac list suggested I ask you to pull that change through my
  tree since they don't have a tree to pull edac changes from at the
  moment."

* 'stable' of git://git.kernel.org/pub/scm/linux/kernel/git/cmetcalf/linux-tile: (39 commits)
  drivers/net/ethernet/tile: fix netdev_alloc_skb() bombing
  MAINTAINERS: update EDAC information
  tilepro ethernet driver: fix a few minor issues
  tile-srom.c driver: minor code cleanup
  edac: say "TILEGx" not "TILEPro" for the tilegx edac driver
  arch/tile: avoid accidentally unmasking NMI-type interrupt accidentally
  arch/tile: remove bogus performance optimization
  arch/tile: return SIGBUS for addresses that are unaligned AND invalid
  arch/tile: fix finv_buffer_remote() for tilegx
  arch/tile: use atomic exchange in arch_write_unlock()
  arch/tile: stop mentioning the "kvm" subdirectory
  arch/tile: export the page_home() function.
  arch/tile: fix pointer cast in cacheflush.c
  arch/tile: fix single-stepping over swint1 instructions on tilegx
  arch/tile: implement panic_smp_self_stop()
  arch/tile: add "nop" after "nap" to help GX idle power draw
  arch/tile: use proper memparse() for "maxmem" options
  arch/tile: fix up locking in pgtable.c slightly
  arch/tile: don't leak kernel memory when we unload modules
  arch/tile: fix bug in delay_backoff()
  ...

Merge tag 'stable/for-linus-3.4-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen

Pull xen fixes from Konrad Rzeszutek Wilk:
 "Two fixes for regressions:
   * one is a workaround that will be removed in v3.5 with proper fix in
     the tip/x86 tree,
   * the other is to fix drivers to load on PV (a previous patch made
     them only load in PVonHVM mode).

  The rest are just minor fixes in the various drivers and some cleanup
  in the core code."

* tag 'stable/for-linus-3.4-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
  xen/pcifront: avoid pci_frontend_enable_msix() falsely returning success
  xen/pciback: fix XEN_PCI_OP_enable_msix result
  xen/smp: Remove unnecessary call to smp_processor_id()
  xen/x86: Workaround 'x86/ioapic: Add register level checks to detect bogus io-apic entries'
  xen: only check xen_platform_pci_unplug if hvm

Pull MMC fixes from Chris Ball:
 - Disable use of MSI in sdhci-pci, which caused multiple chipsets to
   stop working in 3.4-rc1.  I'll wait to turn this on again until we
   have a chipset whitelist for it.
 - Fix a libertas SDIO powered-resume regression introduced in 3.3;
   thanks to Neil Brown and Rafael Wysocki for this fix.
 - Fix module reloading on omap_hsmmc.
 - Stop trusting the spec/card's specified maximum data timeout length,
   and use three seconds instead.  Previously we used 300ms.

Also cleanups and fixes for s3c, atmel, sh_mmcif and omap_hsmmc.

* tag 'mmc-fixes-for-3.4-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/cjb/mmc: (28 commits)
  mmc: use really long write timeout to deal with crappy cards
  mmc: sdhci-dove: Fix compile error by including module.h
  mmc: Prevent 1.8V switch for SD hosts that don't support UHS modes.
  Revert "mmc: sdhci-pci: Add MSI support"
  Revert "mmc: sdhci-pci: add quirks for broken MSI on O2Micro controllers"
  mmc: core: fix power class selection
  mmc: omap_hsmmc: fix module re-insertion
  mmc: omap_hsmmc: convert to module_platform_driver
  mmc: omap_hsmmc: make it behave well as a module
  mmc: omap_hsmmc: trivial cleanups
  mmc: omap_hsmmc: context save after enabling runtime pm
  mmc: omap_hsmmc: use runtime put sync in probe error patch
  mmc: sdio: Use empty system suspend/resume callbacks at the bus level
  mmc: bus: print bus speed mode of UHS-I card
  mmc: sdhci-pci: add quirks for broken MSI on O2Micro controllers
  mmc: sh_mmcif: Simplify calculation of mmc->f_min
  mmc: sh_mmcif: mmc->f_max should be half of the bus clock
  mmc: sh_mmcif: double clock speed
  mmc: block: Remove use of mmc_blk_set_blksize
  mmc: atmel-mci: add support for odd clock dividers
  ...