linux/drivers/target
David Disseldorp 66640d35c1 target: use XCOPY segment descriptor CSCD IDs
The XCOPY specification in SPC4r37 states that the XCOPY source and
destination device(s) should be derived from the copy source and copy
destination (CSCD) descriptor IDs in the XCOPY segment descriptor.

The CSCD IDs are generally (for block -> block copies), indexes into
the corresponding CSCD descriptor list, e.g.
=================================
EXTENDED COPY Header
=================================
CSCD Descriptor List
- entry 0
  + LU ID <--------------<------------------\
- entry 1                                   |
  + LU ID <______________<_____________     |
=================================      |    |
Segment Descriptor List                |    |
- segment 0                            |    |
  + src CSCD ID = 0 --------->---------+----/
  + dest CSCD ID = 1 ___________>______|
  + len
  + src lba
  + dest lba
=================================

Currently LIO completely ignores the src and dest CSCD IDs in the
Segment Descriptor List, and instead assumes that the first entry in the
CSCD list corresponds to the source, and the second to the destination.

This commit removes this assumption, by ensuring that the Segment
Descriptor List is parsed prior to processing the CSCD Descriptor List.
CSCD Descriptor List processing is modified to compare the current list
index with the previously obtained src and dest CSCD IDs.

Additionally, XCOPY requests where the src and dest CSCD IDs refer to
the CSCD Descriptor List entry can now be successfully processed.

Fixes: cbf031f ("target: Add support for EXTENDED_COPY copy offload")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=191381
Signed-off-by: David Disseldorp <ddiss@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
2017-01-10 08:41:19 -08:00
..
iscsi Merge branch 'scsi-target-for-v4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/bvanassche/linux 2016-12-21 10:16:05 -08:00
loopback target: Minimize #include directives 2016-12-09 10:22:28 -08:00
sbp sbp-target: Add an #include directive 2016-12-09 10:20:10 -08:00
tcm_fc Merge branch 'scsi-target-for-v4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/bvanassche/linux 2016-12-21 10:16:05 -08:00
Kconfig target: Put TCMU under a new config option 2015-04-19 22:41:12 -07:00
Makefile target: Put TCMU under a new config option 2015-04-19 22:41:12 -07:00
target_core_alua.c target: Minimize #include directives 2016-12-09 10:22:28 -08:00
target_core_alua.h target: Minimize #include directives 2016-12-09 10:22:28 -08:00
target_core_configfs.c Merge branch 'scsi-target-for-v4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/bvanassche/linux 2016-12-21 10:16:05 -08:00
target_core_device.c target: Minimize #include directives 2016-12-09 10:22:28 -08:00
target_core_fabric_configfs.c fs: configfs: don't return anything from drop_link 2016-12-01 10:50:49 +01:00
target_core_fabric_lib.c Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending 2015-07-04 14:13:43 -07:00
target_core_file.c target: Minimize #include directives 2016-12-09 10:22:28 -08:00
target_core_file.h target: Minimize #include directives 2016-12-09 10:22:28 -08:00
target_core_hba.c target: Fix target_sense_desc_format NULL pointer dereference 2015-09-24 23:17:23 -07:00
target_core_iblock.c block,fs: use REQ_* flags directly 2016-11-01 09:43:26 -06:00
target_core_iblock.h target: Minimize #include directives 2016-12-09 10:22:28 -08:00
target_core_internal.h target: Minimize #include directives 2016-12-09 10:22:28 -08:00
target_core_pr.c target: Fix spelling mistake and unwrap multi-line text 2016-12-16 11:16:08 +01:00
target_core_pr.h target: Minimize #include directives 2016-12-09 10:22:28 -08:00
target_core_pscsi.c target: avoid accessing .bi_vcnt directly 2016-11-22 08:57:55 -07:00
target_core_pscsi.h target: Minimize #include directives 2016-12-09 10:22:28 -08:00
target_core_rd.c target: Minimize #include directives 2016-12-09 10:22:28 -08:00
target_core_rd.h target: Minimize #include directives 2016-12-09 10:22:28 -08:00
target_core_sbc.c target: Minimize #include directives 2016-12-09 10:22:28 -08:00
target_core_spc.c target: Remove enum transport_lunflags_table 2016-03-10 21:48:55 -08:00
target_core_stat.c configfs: switch ->default groups to a linked list 2016-03-06 16:11:24 +01:00
target_core_tmr.c target: Drop incorrect ABORT_TASK put for completed commands 2016-03-05 20:24:47 -08:00
target_core_tpg.c target: remove sess_kref and ->shutdown_session 2016-05-10 01:19:49 -07:00
target_core_transport.c target: add XCOPY target/segment desc sense codes 2017-01-10 08:40:32 -08:00
target_core_ua.c Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending 2015-07-04 14:13:43 -07:00
target_core_ua.h target: Minimize #include directives 2016-12-09 10:22:28 -08:00
target_core_user.c Merge branch 'scsi-target-for-v4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/bvanassche/linux 2016-12-21 10:16:05 -08:00
target_core_xcopy.c target: use XCOPY segment descriptor CSCD IDs 2017-01-10 08:41:19 -08:00
target_core_xcopy.h target: check XCOPY segment descriptor CSCD IDs 2017-01-10 08:41:13 -08:00