Commit Graph

41 Commits

Author SHA1 Message Date
Nicholas Bellinger bdbad2bdcb target/spc: Add protection bit to standard INQUIRY output
This patch updates spc_emulate_inquiry_std() to set the
PROTECT bit when DIF emulation is enabled by the backend
device.

Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Sagi Grimberg <sagig@mellanox.com>
Cc: Or Gerlitz <ogerlitz@mellanox.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2014-01-18 09:53:12 +00:00
Nicholas Bellinger f82f320edc target: Convert inquiry temporary buffer to heap memory
This patch converts the temporary buffer in spc_emulate_inquiry() to
use dynamically allocated memory, instead of local stack memory.

Also bump SE_INQUIRY_BUF up to 1024 bytes to be safe when handling
multiple large SCSI name descriptors for EVPD=0x83.

Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2014-01-09 21:48:38 -08:00
Hannes Reinecke c66094bf32 target_core_alua: Referrals infrastructure
Add infrastructure for referrals.

v2 changes:

 - Fix unsigned long long division in core_alua_state_lba_dependent on
   32-bit  (Fengguang + Chen + Hannes)
 - Fix compile warning in core_alua_state_lba_dependent (nab)
 - Convert segment_* + sectors variables in core_alua_state_lba_dependent
   to u64 (Hannes)

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2014-01-09 21:48:17 -08:00
Hannes Reinecke fbfe858fea target_core_spc: Include target device descriptor in VPD page 83
We should be including a descriptor referring to the target device
to allow identification of different TCM instances.

(nab: Bump SE_INQUIRY_BUF to 1024 bytes to handle 2x 256 byte SCSI names)

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-12-17 18:04:30 -08:00
Hannes Reinecke 03ba84ca95 target_core: simplify scsi_name_len calculation
scsi_name_len in spc_emulate_evpd_83 is calculated twice, with
the results of the first calculation discarded. So remove it.
And check for the maximum allowed length, too.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-12-17 11:05:33 -08:00
Hannes Reinecke 125d0119d1 target core: rename (ex,im)plict -> (ex,im)plicit
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-11-20 11:24:40 -08:00
Andy Grover 7f7caf6aa7 target: Pass through I/O topology for block backstores
In addition to block size (already implemented), passing through
alignment offset, logical-to-phys block exponent, I/O granularity and
optimal I/O length will allow initiators to properly handle layout on
LUNs with 4K block sizes.

Tested with various weird values via scsi_debug module.

One thing to look at with this patch is the new block limits values --
instead of granularity 1 optimal 8192, Lio will now be returning whatever
the block device says, which may affect performance.

Signed-off-by: Andy Grover <agrover@redhat.com>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-11-12 13:44:54 -08:00
Linus Torvalds 48efe453e6 Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending
Pull SCSI target updates from Nicholas Bellinger:
 "Lots of activity again this round for I/O performance optimizations
  (per-cpu IDA pre-allocation for vhost + iscsi/target), and the
  addition of new fabric independent features to target-core
  (COMPARE_AND_WRITE + EXTENDED_COPY).

  The main highlights include:

   - Support for iscsi-target login multiplexing across individual
     network portals
   - Generic Per-cpu IDA logic (kent + akpm + clameter)
   - Conversion of vhost to use per-cpu IDA pre-allocation for
     descriptors, SGLs and userspace page pointer list
   - Conversion of iscsi-target + iser-target to use per-cpu IDA
     pre-allocation for descriptors
   - Add support for generic COMPARE_AND_WRITE (AtomicTestandSet)
     emulation for virtual backend drivers
   - Add support for generic EXTENDED_COPY (CopyOffload) emulation for
     virtual backend drivers.
   - Add support for fast memory registration mode to iser-target (Vu)

  The patches to add COMPARE_AND_WRITE and EXTENDED_COPY support are of
  particular significance, which make us the first and only open source
  target to support the full set of VAAI primitives.

  Currently Linux clients are lacking upstream support to actually
  utilize these primitives.  However, with server side support now in
  place for folks like MKP + ZAB working on the client, this logic once
  reserved for the highest end of storage arrays, can now be run in VMs
  on their laptops"

* 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending: (50 commits)
  target/iscsi: Bump versions to v4.1.0
  target: Update copyright ownership/year information to 2013
  iscsi-target: Bump default TCP listen backlog to 256
  target: Fix >= v3.9+ regression in PR APTPL + ALUA metadata write-out
  iscsi-target; Bump default CmdSN Depth to 64
  iscsi-target: Remove unnecessary wait_for_completion in iscsi_get_thread_set
  iscsi-target: Add thread_set->ts_activate_sem + use common deallocate
  iscsi-target: Fix race with thread_pre_handler flush_signals + ISCSI_THREAD_SET_DIE
  target: remove unused including <linux/version.h>
  iser-target: introduce fast memory registration mode (FRWR)
  iser-target: generalize rdma memory registration and cleanup
  iser-target: move rdma wr processing to a shared function
  target: Enable global EXTENDED_COPY setup/release
  target: Add Third Party Copy (3PC) bit in INQUIRY response
  target: Enable EXTENDED_COPY setup in spc_parse_cdb
  target: Add support for EXTENDED_COPY copy offload emulation
  target: Avoid non-existent tg_pt_gp_mem in target_alua_state_check
  target: Add global device list for EXTENDED_COPY
  target: Make helpers non static for EXTENDED_COPY command setup
  target: Make spc_parse_naa_6h_vendor_specific non static
  ...
2013-09-12 16:11:45 -07:00
Nicholas Bellinger 4c76251e8e target: Update copyright ownership/year information to 2013
Update copyright ownership/year information for target-core,
loopback, iscsi-target, tcm_qla2xx, vhost and iser-target.

Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-09-10 20:23:36 -07:00
Nicholas Bellinger d397a445f4 target: Add Third Party Copy (3PC) bit in INQUIRY response
This patch adds the Third Party Copy (3PC) bit to signal support
for EXTENDED_COPY within standard inquiry response data.

Also add emulate_3pc device attribute in configfs (enabled by default)
to allow the exposure of this bit to be disabled, if necessary.

Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Martin Petersen <martin.petersen@oracle.com>
Cc: Chris Mason <chris.mason@fusionio.com>
Cc: Roland Dreier <roland@purestorage.com>
Cc: Zach Brown <zab@redhat.com>
Cc: James Bottomley <JBottomley@Parallels.com>
Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Nicholas Bellinger <nab@daterainc.com>
2013-09-10 16:48:46 -07:00
Nicholas Bellinger 04b1b79546 target: Enable EXTENDED_COPY setup in spc_parse_cdb
Setup up the se_cmd->execute_cmd() pointers for EXTENDED_COPY and
RECEIVE_COPY_RESULTS handling within spc_parse_cdb()

Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Martin Petersen <martin.petersen@oracle.com>
Cc: Chris Mason <chris.mason@fusionio.com>
Cc: Roland Dreier <roland@purestorage.com>
Cc: Zach Brown <zab@redhat.com>
Cc: James Bottomley <JBottomley@Parallels.com>
Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Nicholas Bellinger <nab@daterainc.com>
2013-09-10 16:48:44 -07:00
Nicholas Bellinger 68366026a5 target: Make spc_parse_naa_6h_vendor_specific non static
This patch makes spc_parse_naa_6h_vendor_specific() available to
other target code, which is required by EXTENDED_COPY when comparing
the received NAA WWN device identifer for locating the associated
se_device backend.

Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Martin Petersen <martin.petersen@oracle.com>
Cc: Chris Mason <chris.mason@fusionio.com>
Cc: Roland Dreier <roland@purestorage.com>
Cc: Zach Brown <zab@redhat.com>
Cc: James Bottomley <JBottomley@Parallels.com>
Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Nicholas Bellinger <nab@daterainc.com>
2013-09-10 16:48:37 -07:00
Nicholas Bellinger 0123a9ec6a target: Add MAXIMUM COMPARE AND WRITE LENGTH in Block Limits VPD
This patch adds the MAXIMUM COMPARE AND WRITE LENGTH bit, currently
hardcoded to a single logical block (NoLB=1) within the Block Limits
VPD in spc_emulate_evpd_b0().

Also add emulate_caw device attribute in configfs (enabled by default)
to allow the exposure of this bit to be disabled, if necessary.

Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Martin Petersen <martin.petersen@oracle.com>
Cc: Chris Mason <chris.mason@fusionio.com>
Cc: James Bottomley <JBottomley@Parallels.com>
Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Nicholas Bellinger <nab@daterainc.com>
2013-09-09 14:29:35 -07:00
Nicholas Bellinger ee60bddba5 target: Fix trailing ASCII space usage in INQUIRY vendor+model
This patch fixes spc_emulate_inquiry_std() to add trailing ASCII
spaces for INQUIRY vendor + model fields following SPC-4 text:

  "ASCII data fields described as being left-aligned shall have any
   unused bytes at the end of the field (i.e., highest offset) and
   the unused bytes shall be filled with ASCII space characters (20h)."

This addresses a problem with Falconstor NSS multipathing.

Reported-by: Tomas Molota <tomas.molota@lightstorm.sk>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-08-12 19:11:26 -07:00
Roland Dreier 71f41fe1fa target: Fix parameter list length checking in MODE SELECT
An empty parameter list (length == 0) is not an error, so succeed MODE
SELECT in this case.  If the parameter list length is too small,
return the correct sense code of PARAMETER LIST LENGTH ERROR.

Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-02-13 12:16:11 -08:00
Nicholas Bellinger d0c8b259f8 target/iblock: Use backend REQ_FLUSH hint for WriteCacheEnabled status
This patch allows IBLOCK to check block hints in request_queue->flush_flags
when reporting current backend device WriteCacheEnabled status to a remote
SCSI initiator port.

This is done via a se_subsystem_api->get_write_cache() call instead of a
backend se_device creation time flag, as we expect REQ_FLUSH bits to possibly
change from an underlying blk_queue_flush() by the SCSI disk driver, or
internal raw struct block_device driver usage.

Also go ahead and update iblock_execute_rw() bio I/O path code to use
REQ_FLUSH + REQ_FUA hints when determining WRITE_FUA usage, and make SPC
emulation code use a spc_check_dev_wce() helper to handle both types of
cases for virtual backend subsystem drivers.

(asias: Drop unnecessary comparsion operators)

Reported-by: majianpeng <majianpeng@gmail.com>
Cc: majianpeng <majianpeng@gmail.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: James Bottomley <JBottomley@Parallels.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-02-13 11:27:51 -08:00
Hannes Reinecke 0dfa1c5da3 target: Export SPC inquiry emulation
Some target drivers might need to access the inquiry data
directly, without sending out the actual command.
So export these functions.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Cc: Nicholas Bellinger <nab@risingtidesystems.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-02-13 11:27:22 -08:00
Nicholas Bellinger cab9609b44 target: Fix zero-length MODE_SENSE regression
This patch fixes a regression introduced in v3.8-rc1 code where
a zero-length MODE_SENSE was no longer returning GOOD status, but
instead returning TCM_LOGICAL_UNIT_COMMUNICATION_FAILURE to generate
a CHECK_CONDITION status.

This regression was introduced with the following commit:

  commit de103c93af
  Author: Christoph Hellwig <hch@lst.de>
  Date:   Tue Nov 6 12:24:09 2012 -0800

      target: pass sense_reason as a return value

and this patch has been tested with the following zero-length CDB:

  sg_raw /dev/sdd 5a 00 0a 00 00 00 00 00 00 00
  SCSI Status: Good

  Sense Information:
  sense buffer empty

Cc: Christoph Hellwig <hch@lst.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-01-29 14:24:20 -08:00
Nicholas Bellinger 49df9fc9b9 target: Fix zero-length INQUIRY additional sense code regression
This patch fixes a minor regression introduced in v3.8-rc1 code
where a zero-length INQUIRY was no longer returning the correct
INVALID FIELD IN CDB additional sense code.

This regression was introduced with the following commit:

  commit de103c93af
  Author: Christoph Hellwig <hch@lst.de>
  Date:   Tue Nov 6 12:24:09 2012 -0800

      target: pass sense_reason as a return value

and this patch has been tested with the following zero-length CDB:

  sg_raw /dev/sdd 12 00 83 00 00 00
  SCSI Status: Check Condition

  Sense Information:
   Fixed format, current;  Sense key: Illegal Request
   Additional sense: Invalid field in cdb

Cc: Christoph Hellwig <hch@lst.de>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-01-29 14:22:01 -08:00
Nicholas Bellinger fd9a11d707 target: Update copyright information to 2012
v2: Use correct target_core_stat.c 2006 copyright year
v3: Drop extra unnessary legal verbage from header (hch)

Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-11-27 22:47:02 -08:00
Nicholas Bellinger 773cbaf746 target: Add/check max_write_same_len device attribute + update block limits VPD
This patch adds a new max_write_same_len device attribute for use with
WRITE_SAME w/ UNMAP=0 backend emulation.  This can be useful for
lowering the default backend value (IBLOCK uses 0xFFFF).

Also, update block limits VPD emulation code in spc_emulate_evpd_b0() to
report MAXIMUM WRITE SAME LENGTH, and enforce max_write_same_len during
sbc_parse() -> sbc_setup_write_same() CDB sanity checking for all emulated
WRITE_SAME w/ UNMAP=0 cases.

(Robert: Move max_write_same_len check in sbc_setup_write_same() to
         check both WRITE_SAME w/ UNMAP=1 and w/ UNMAP=0 cases)

Cc: Christoph Hellwig <hch@lst.de>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Robert Elliott <Elliott@hp.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-11-15 12:27:21 -08:00
Christoph Hellwig de103c93af target: pass sense_reason as a return value
Pass the sense reason as an explicit return value from the I/O submission
path instead of storing it in struct se_cmd and using negative return
values.  This cleans up a lot of the code pathes, and with the sparse
annotations for the new sense_reason_t type allows for much better
error checking.

(nab: Convert spc_emulate_modesense + spc_emulate_modeselect to use
      sense_reason_t with Roland's MODE SELECT changes)

Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-11-06 20:55:46 -08:00
Nicholas Bellinger fecae40abb target: Fix incorrect starting offset after MODE_SENSE refactoring
This patch fixes a new off-by-one bug in the hardcoded starting offset of
spc_emulate_modesense() code that causes BLOCK DESCRIPTOR to be incorrectly
written within the MEDIUM TYPE buffer area of the mode parameter header.

According to spc4r30, Section 7.5.4, BLOCK DESCRIPTOR for MODE_SENSE_10
starts at byte 3, and BLOCK_DESCRIPTOR for MODE_SENSE (6) starts at byte 2.

(roland: add MODE DATA LENGTH + MEDIUM TYPE offset comment)

Cc: Roland Dreier <roland@purestorage.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Douglas Gilbert <dgilbert@interlog.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-11-06 20:55:46 -08:00
Roland Dreier 3a3c5e4a67 target: Add emulation for MODE SELECT
This is another thing that compliance tests try, and it's easy to
implement on top of the MODE SENSE refactoring; since we don't claim
to support any changeable values, all we need to do is check that
the page contents sent by the initiator match what we would return.

Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-11-06 20:55:46 -08:00
Roland Dreier 0f6d64cee9 target: Implement mode page 0x1c, "Informational Exceptions"
The Windows SCSI compliance test asks for this mode page, and it's
easy to implement: we can just return all 0s to show we don't support
any of these features.

Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-11-06 20:55:46 -08:00
Roland Dreier d4b2b86719 target: Refactor MODE SENSE emulation
Convert spc_emulate_modesense() to use a table of mode pages, rather
than a switch statement.  This makes it possible to add more pages
sanely -- in particular we no longer need to make sure we keep the
0x3f (return all mode pages) case in sync.

While we're touching this code, make our MODE SENSE emulation a bit
better in a couple of ways:
 - When the initiator passes PC == 1 asking for changeable values,
   return all 0s to show we don't support setting anything.
 - Return a block descriptor for disk devices.

(nab: fix up device attribute references to use dev->dev_attrib
      in for-next code)

Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-11-06 20:55:46 -08:00
Christoph Hellwig 48c2567d1a target: remove ->get_device_rev
Now that the reservations and ALUA code have been cleaned up there is no need
for the get_device_rev method, as we only need the standards revision in the
inquiry data, where we can hardcode it.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-11-06 20:55:45 -08:00
Christoph Hellwig c87fbd5656 target: simplify alua support
We always support ALUA for virtual backends, and never for physical ones.  Simplify
the code to just deal with these two cases and remove the superflous abstractions.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-11-06 20:55:45 -08:00
Christoph Hellwig d977f4377f target: simplify reservations code
We do not support host-level reservations for the pscsi backend, and all
virtual backends are newere than SCSI-2, so just make the combined
SPC-3 + SCSI-2 support the only supported variant and kill the switches
for the different implementations, given that this code handles the no-op
version just fine.

(hch: Update DRF_SPC2_RESERVATIONS lock usage)

Signed-off-by: Christoph Hellwig <hch@lst.de>
2012-11-06 20:55:45 -08:00
Christoph Hellwig 019c4ca621 target: kill dev->dev_task_attr_type
We can just key off ordered tag emulation of the transport_type field.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-11-06 20:55:45 -08:00
Christoph Hellwig 8de530a523 target/pscsi: call spc_emulate_report_luns directly
No need to indirect through spc_parse_cdb if we only ever call it for
REPORT LUNS emulation.

(nab: Add missing EXPORT_SYMBOL for spc_emulate_report_luns)

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-11-06 20:55:44 -08:00
Christoph Hellwig d1b1f80534 target: move REPORT LUNS emulation to target_core_spc.c
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-11-06 20:55:44 -08:00
Christoph Hellwig 0fd97ccf45 target: kill struct se_subsystem_dev
Simplify the code a lot by killing the superflous struct se_subsystem_dev.
Instead se_device is allocated early on by the backend driver, which allocates
it as part of its own per-device structure, borrowing the scheme that is for
example used for inode allocation.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-11-06 20:55:43 -08:00
Nicholas Bellinger dea5f0998a target: Re-add explict zeroing of INQUIRY bounce buffer memory
This patch fixes a regression in spc_emulate_inquiry() code where the
local scope bounce buffer was no longer getting it's memory zeroed,
causing various problems with SCSI initiators that depend upon areas
of INQUIRY EVPD=0x83 payload having been zeroed.

This bug was introduced with the following v3.7-rc1 patch + CC'ed
stable commit:

commit ffe7b0e932
Author: Paolo Bonzini <pbonzini@redhat.com>
Date:   Fri Sep 7 17:30:38 2012 +0200

    target: support zero allocation length in INQUIRY

Go ahead and re-add the missing memset of bounce buffer memory to be
copied into the outgoing se_cmd descriptor kmapped SGL payload.

Reported-by: Kelsey Prantis <kelsey.prantis@intel.com>
Cc: Kelsey Prantis <kelsey.prantis@intel.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Andy Grover <agrover@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-10-31 22:17:12 -07:00
Paolo Bonzini 7a3f369ce3 target: fix truncation of mode data, support zero allocation length
The offset was not bumped back to the full size after writing the
header of the MODE SENSE response, so the last 1 or 2 bytes were
not copied.

On top of this, support zero-length requests by checking for the
return value of transport_kmap_data_sg.

Testcase: sg_raw -r20 /dev/sdb 5a 00 0a 00 00 00 00 00 14 00
    last byte should be 0x1e
    it is 0x00 without the patch
    it is correct with the patch

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-09-17 17:13:37 -07:00
Paolo Bonzini ffe7b0e932 target: support zero allocation length in INQUIRY
INQUIRY processing already uses an on-heap bounce buffer for loopback,
but not for other fabrics.  Switch this to a cheaper on-stack bounce
buffer, similar to the one used by MODE SENSE and REQUEST SENSE, and
use it unconditionally.  With this in place, zero allocation length is
handled simply by checking the return address of transport_kmap_data_sg.

Testcase: sg_raw /dev/sdb 12 00 83 00 00 00
    should fail with ILLEGAL REQUEST / INVALID FIELD IN CDB sense
    does not fail without the patch
    fails correctly with the series

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-09-17 17:13:36 -07:00
Paolo Bonzini 32a8811ff1 target: support zero allocation length in REQUEST SENSE
Similar to INQUIRY and MODE SENSE, construct the sense data in a
buffer and later copy it to the scatterlist.  Do not do anything,
but still clear a pending unit attention condition, if the allocation
length is zero.

However, SPC tells us that "If a REQUEST SENSE command is terminated with
CHECK CONDITION status [and] the REQUEST SENSE command was received on
an I_T nexus with a pending unit attention condition (i.e., before the
device server reports CHECK CONDITION status), then the device server
shall not clear the pending unit attention condition."  Do the
transport_kmap_data_sg early to detect this case.

It also tells us "Device servers shall not adjust the additional sense
length to reflect truncation if the allocation length is less than the
sense data available", so do not do that!  Note that the err variable
is write-only.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-09-07 11:14:21 -07:00
Nicholas Bellinger eba2ca4505 target: Move MAINTENANCE_[IN,OUT] from pscsi_parse_cdb -> spc_parse_cdb
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>
2012-07-16 17:28:40 -07:00
Christoph Hellwig 1fd032ee10 target: move code for CDB emulation
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>
2012-07-16 17:27:45 -07:00
Christoph Hellwig d6e0175cf3 target: add a parse_cdb method to the backend drivers
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>
2012-07-16 17:25:56 -07:00
Christoph Hellwig 88455ec4be target: split parsing of SPC commands into a separate helper
(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>
2012-07-16 17:25:56 -07:00