linux.git/drivers/target/target_core_device.c, branch v4.1

target: Use a PASSTHROUGH flag instead of transport_types

2015-05-31T02:58:11+00:00

It seems like we only care if a transport is passthrough or not. Convert
transport_type to a flags field and replace TRANSPORT_PLUGIN_* with a
flag, TRANSPORT_FLAG_PASSTHROUGH.

Signed-off-by: Andy Grover 
Reviewed-by: Ilias Tsitsimpis 
Signed-off-by: Nicholas Bellinger

target: Move passthrough CDB parsing into a common function

2015-05-31T02:57:59+00:00

Aside from whether they handle BIDI ops or not, parsing of the CDB by
kernel and user SCSI passthrough modules should be identical. Move this
into a new passthrough_parse_cdb() and call it from tcm-pscsi and tcm-user.

Reported-by: Christoph Hellwig 
Reviewed-by: Ilias Tsitsimpis 
Signed-off-by: Andy Grover 
Signed-off-by: Nicholas Bellinger

target: Allow userspace to write 1 to attrib/emulate_fua_write

2015-04-02T04:42:51+00:00

Before 4.0, reading attrib/emulate_fua_write has returned 1. Saved
configs created on a pre-4.0 kernel will try to write that back when
restoring LIO configuration. This should succeed with no effect,
and issue a warning.

See https://bugzilla.redhat.com/show_bug.cgi?id=1206184

Reported-by: Yanko Kaneti 
Reported-by: Juan Quintela 
Signed-off-by: Andy Grover 
Signed-off-by: Nicholas Bellinger

target: do not reject FUA CDBs when write cache is enabled but emulate_write_cache is 0

2015-03-20T06:26:46+00:00

A check that rejects a CDB with FUA bit set if no write cache is
emulated was added by the following commit:

  fde9f50 target: Add sanity checks for DPO/FUA bit usage

The condition is as follows:

  if (!dev->dev_attrib.emulate_fua_write ||
      !dev->dev_attrib.emulate_write_cache)

However, this check is wrong if the backend device supports WCE but
"emulate_write_cache" is disabled.

This patch uses se_dev_check_wce() (previously named
spc_check_dev_wce) to invoke transport->get_write_cache() if the
device has a write cache or check the "emulate_write_cache" attribute
otherwise.

Reported-by: Christoph Hellwig 
Signed-off-by: Christophe Vu-Brugier 
Signed-off-by: Nicholas Bellinger

target: Fix virtual LUN=0 target_configure_device failure OOPs

2015-03-20T06:26:44+00:00

This patch fixes a NULL pointer dereference triggered by a late
target_configure_device() -> alloc_workqueue() failure that results
in target_free_device() being called with DF_CONFIGURED already set,
which subsequently OOPses in destroy_workqueue() code.

Currently this only happens at modprobe target_core_mod time when
core_dev_setup_virtual_lun0() -> target_configure_device() fails,
and the explicit target_free_device() gets called.

To address this bug originally introduced by commit 0fd97ccf45, go
ahead and move DF_CONFIGURED to end of target_configure_device()
code to handle this special failure case.

Reported-by: Claudio Fleiner 
Cc: Claudio Fleiner 
Cc: Christoph Hellwig 
Cc:  # v3.7+
Signed-off-by: Nicholas Bellinger

target: Disallow changing of WRITE cache/FUA attrs after export

2015-03-20T06:01:04+00:00

Now that incoming FUA=1 bit check is enforced for backends with FUA or
WCE disabled, go ahead and disallow the changing of related backend
attributes when active fabric exports exist.

This is required to avoid potential failures with existing initiator
LUN registrations that have been previously created with FUA=1.

Reported-by: Christoph Hellwig 
Cc: Doug Gilbert 
Cc: James Bottomley 
Cc: Ronnie Sahlberg 
Signed-off-by: Nicholas Bellinger

target: Drop left-over fabric_max_sectors attribute

2015-01-09T23:22:05+00:00

Now that fabric_max_sectors is no longer used to enforce the maximum
I/O size, go ahead and drop it's left-over usage in target-core and
associated backend drivers.

Cc: Christoph Hellwig 
Cc: Martin K. Petersen 
Cc: Roland Dreier 
Signed-off-by: Nicholas Bellinger

target: Drop arbitrary maximum I/O size limit

2015-01-09T23:21:40+00:00

This patch drops the arbitrary maximum I/O size limit in sbc_parse_cdb(),
which currently for fabric_max_sectors is hardcoded to 8192 (4 MB for 512
byte sector devices), and for hw_max_sectors is a backend driver dependent
value.

This limit is problematic because Linux initiators have only recently
started to honor block limits MAXIMUM TRANSFER LENGTH, and other non-Linux
based initiators (eg: MSFT Fibre Channel) can also generate I/Os larger
than 4 MB in size.

Currently when this happens, the following message will appear on the
target resulting in I/Os being returned with non recoverable status:

  SCSI OP 28h with too big sectors 16384 exceeds fabric_max_sectors: 8192

Instead, drop both [fabric,hw]_max_sector checks in sbc_parse_cdb(),
and convert the existing hw_max_sectors into a purely informational
attribute used to represent the granuality that backend driver and/or
subsystem code is splitting I/Os upon.

Also, update FILEIO with an explicit FD_MAX_BYTES check in fd_execute_rw()
to deal with the one special iovec limitiation case.

v2 changes:
  - Drop hw_max_sectors check in sbc_parse_cdb()

Reported-by: Lance Gropper 
Reported-by: Stefan Priebe 
Cc: Christoph Hellwig 
Cc: Martin K. Petersen 
Cc: Roland Dreier 
Cc: stable@vger.kernel.org # 3.4
Signed-off-by: Nicholas Bellinger

target: Drop left-over PHBA_PDEV set attr checks

2014-12-02T05:36:21+00:00

Now that PSCSI is only exposing four hw_* read-only device attributes,
go ahead and drop the left-over -> legacy PHBA_PDEV checks in various
se_dev_set_* code, since it's now only used by virtual devices.

Signed-off-by: Nicholas Bellinger

target: Add EXPORT_SYMBOL for existing se_dev_set_*

2014-12-02T05:36:02+00:00

Now that target_core_backend_configfs.h macros will be using these
se_dev_set attribute functions externally to allow backend drivers
to populate different attributes, go ahead and add EXPORT_SYMBOL()
for the existing default set of 30 device attributes.

Also update target_core_backend.h with proper function prototypes.

Signed-off-by: Nicholas Bellinger