Commit Graph

17 Commits

Author SHA1 Message Date
Andy Grover
8ee83a747a target/user: Disallow full passthrough (pass_level=0)
TCMU requires more work to correctly handle both user handlers that want
all SCSI commands (pass_level=0) for a se_device, and also handlers that
just want I/O commands and let the others be emulated by the kernel
(pass_level=1). Only support the latter for now.

For full passthrough, we will need to support a second se_subsystem_api
template, due to configfs attributes being different between the two modes.
Thus pass_level is extraneous, and we can remove it.

The ABI break for TCMU v2 is already applied for this release, so it's
best to do this now to avoid another ABI break in the future.

Signed-off-by: Andy Grover <agrover@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2015-05-02 18:20:51 -07:00
Andy Grover
0ad46af8a6 target: Version 2 of TCMU ABI
The initial version of TCMU (in 3.18) does not properly handle
bidirectional SCSI commands -- those with both an in and out buffer. In
looking to fix this it also became clear that TCMU's support for adding
new types of entries (opcodes) to the command ring was broken. We need
to fix this now, so that future issues can be handled properly by adding
new opcodes.

We make the most of this ABI break by enabling bidi cmd handling within
TCMP_OP_CMD opcode. Add an iov_bidi_cnt field to tcmu_cmd_entry.req.
This enables TCMU to describe bidi commands, but further kernel work is
needed for full bidi support.

Enlarge tcmu_cmd_entry_hdr by 32 bits by pulling in cmd_id and __pad1. Turn
__pad1 into two 8 bit flags fields, for kernel-set and userspace-set flags,
"kflags" and "uflags" respectively.

Update version fields so userspace can tell the interface is changed.

Update tcmu-design.txt with details of how new stuff works:
- Specify an additional requirement for userspace to set UNKNOWN_OP
  (bit 0) in hdr.uflags for unknown/unhandled opcodes.
- Define how Data-In and Data-Out fields are described in req.iov[]

Changed in v2:
- Change name of SKIPPED bit to UNKNOWN bit
- PAD op does not set the bit any more
- Change len_op helper functions to take just len_op, not the whole struct
- Change version to 2 in missed spots, and use defines
- Add 16 unused bytes to cmd_entry.req, in case additional SAM cmd
  parameters need to be included
- Add iov_dif_cnt field to specify buffers used for DIF info in iov[]
- Rearrange fields to naturally align cdb_off
- Handle if userspace sets UNKNOWN_OP by indicating failure of the cmd
- Wrap some overly long UPDATE_HEAD lines

(Add missing req.iov_bidi_cnt + req.iov_dif_cnt zeroing - Ilias)

Signed-off-by: Andy Grover <agrover@redhat.com>
Reviewed-by: Ilias Tsitsimpis <iliastsi@arrikto.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2015-04-19 22:40:26 -07:00
Christoph Hellwig
65204c84d7 target: fix tcm_mod_builder.py
Fix a misplaced comma I introduced.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2015-04-15 22:47:28 -07:00
Christoph Hellwig
9ac8928e6a target: simplify the target template registration API
Instead of calling target_fabric_configfs_init() +
target_fabric_configfs_register() / target_fabric_configfs_deregister()
target_fabric_configfs_free() from every target driver, rewrite the API
so that we have simple register/unregister functions that operate on
a const operations vector.

This patch also fixes a memory leak in several target drivers. Several
target drivers namely called target_fabric_configfs_deregister()
without calling target_fabric_configfs_free().

A large part of this patch is based on earlier changes from
Bart Van Assche <bart.vanassche@sandisk.com>.

(v2: Add a new TF_CIT_SETUP_DRV macro so that the core configfs code
can declare attributes as either core only or for drivers)

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2015-04-14 12:28:41 -07:00
Nicholas Bellinger
67e51daa50 Documentation/target: Update fabric_ops to latest code
This patch updates tcm_mod_builder.py to add/drop a handful of
struct target_core_fabric_ops functions to sync up with the
latest requirements to function in target_fabric_tf_ops_check().

Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2015-01-06 13:46:49 -08:00
Andy Grover
ce87685128 target: Add documentation on the target userspace pass-through driver
Describes the driver and its interface to make it possible for user
programs to back a LIO-exported LUN.

Thanks to Richard W. M. Jones for review, and supplementing this doc
with the first two paragraphs.

Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2014-10-02 21:35:54 -07:00
Andy Grover
d80e224dd5 target: Remove TF_CIT_TMPL macro
Remove a lingering macro that just hid a dereference.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andy Grover <agrover@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2013-10-16 13:35:02 -07:00
Jingoo Han
0ab943bf56 Documentation: replace strict_strtoul() with kstrtoul()
The usage of strict_strtoul() is not preferred, because
strict_strtoul() is obsolete. Thus, kstrtoul() should be
used.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2013-08-20 12:56:26 +02:00
Roland Dreier
9c58b7ddd7 target: Simplify fabric sense data length handling
Every fabric driver has to supply a se_tfo->set_fabric_sense_len()
method, just so iSCSI can return an offset of 2.  However, every fabric
driver is already allocating a sense buffer and passing it into the
target core, either via transport_init_se_cmd() or target_submit_cmd().

So instead of having iSCSI pass the start of its sense buffer into the
core and then later tell the core to skip the first 2 bytes, it seems
easier for iSCSI just to do the offset of 2 when it passes the sense
buffer into the core.  Then we can drop the se_tfo->set_fabric_sense_len()
everywhere, and just add a couple of lines of code to iSCSI to set the
sense data length to the beginning of the buffer right before it sends
it over the network.

(nab: Remove .set_fabric_sense_len usage from tcm_qla2xxx_npiv_ops +
      change transport_get_sense_buffer to follow v3.6-rc6 code w/o
      ->set_fabric_sense_len usage)

Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-09-17 17:12:58 -07:00
Roland Dreier
2ed772b7b9 target: Remove unused target_core_fabric_ops.get_fabric_sense_len method
There are no callers of se_tfo->get_fabric_sense_len(), so we should
stop having every fabric driver implement it.

Signed-off-by: Roland Dreier <roland@purestorage.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2012-09-17 16:15:47 -07:00
Masanari Iida
26725f2ad6 Documentation: Fix typo in tcm_mod_builder.py
Correct spelling "alocate" to "allocate" in
Documentation/target/tcm_mod_builder.py

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2012-02-10 09:52:18 +01:00
Sebastian Andrzej Siewior
ced38c8c00 target: tcm_mod_builder: small fixups
This includes:
- remove on _ in "__NAMELEN" in $fabric _make_tport
- target_fabric_configfs_init() returns an error pointer and not NULL
  anymore. Consider that.
- replace (!(var_name)) with (!var_name). The extra () are not required
- remove #ifdef MODULE. If the code is builtin it needs an init function
  or the code is useless
- put exit/clean functions into __exit

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-14 11:38:25 +00:00
Nicholas Bellinger
77271de645 Documentation/target: Fix tcm_mod_builder.py build breakage
This patch fixes TFO->release_cmd() and removes legacy pack_lun() usage
and new_cmd_failure when generating new TCM fabric skeleton from the
tcm_mod_builder.py script.

Reported-by: Stefan Bergstrand <stefan.bergstrand@sdsab.se>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-14 11:37:37 +00:00
Christoph Hellwig
c4795fb20e target: header reshuffle, part2
This reorganized the headers under include/target into:

 - target_core_base.h stays as is with all target-wide data stuctures and defines
 - target_core_backend.h contains the whole interface to I/O backends
 - target_core_fabric.h contains the whole interface to fabric modules

Except for those only the various configfs macro headers stay around.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
2011-12-14 11:26:05 +00:00
Fubo Chen
f45934e08c [SCSI] tcm_mod_builder.py: Fix generated *_drop_nodeacl() handler
This patch adds the missing core_tpg_del_initiator_node_acl() call required
by fabric modules for struct se_node_acl->acl_group context shutdown via

	target_core_fabric_configfs.c:target_fabric_nacl_base_release() ->

		struct target_core_fabric_ops->fabric_drop_nodeacl()

for tcm_mod_builder.py generated $FABRIC_MOD_configfs.c skeleton code.

Signed-off-by: Fubo Chen <fubo.chen@gmail.com>
Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-03-23 11:36:45 -05:00
Nicholas Bellinger
10635c8b71 [SCSI] target: tcm_mod_builder.py generated Makefile cleanups
This patch converts the tcm_mod_builder.py generation script to
create a new drivers/target/$TCM_FABRIC_MOD/Makefile and update
drivers/target/Makefile, instead of creating+updating a 'Kbuild'
filename.

It also removes the remaining EXTRA_CFLAGS includes from
tcm_mod_build_kbuild(), and converts fabric module generated .c
code to us ""-style includes for $FABRIC_MOD_[base,fabric].h

Reported-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-03-23 11:36:22 -05:00
Nicholas Bellinger
c66ac9db8d [SCSI] target: Add LIO target core v4.0.0-rc6
LIO target is a full featured in-kernel target framework with the
following feature set:

High-performance, non-blocking, multithreaded architecture with SIMD
support.

Advanced SCSI feature set:

    * Persistent Reservations (PRs)
    * Asymmetric Logical Unit Assignment (ALUA)
    * Protocol and intra-nexus multiplexing, load-balancing and failover (MC/S)
    * Full Error Recovery (ERL=0,1,2)
    * Active/active task migration and session continuation (ERL=2)
    * Thin LUN provisioning (UNMAP and WRITE_SAMExx)

Multiprotocol target plugins

Storage media independence:

    * Virtualization of all storage media; transparent mapping of IO to LUNs
    * No hard limits on number of LUNs per Target; maximum LUN size ~750 TB
    * Backstores: SATA, SAS, SCSI, BluRay, DVD, FLASH, USB, ramdisk, etc.

Standards compliance:

    * Full compliance with IETF (RFC 3720)
    * Full implementation of SPC-4 PRs and ALUA

Significant code cleanups done by Christoph Hellwig.

[jejb: fix up for new block bdev exclusive interface. Minor fixes from
 Randy Dunlap and Dan Carpenter.]
Signed-off-by: Nicholas A. Bellinger <nab@linux-iscsi.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2011-01-14 10:12:29 -06:00